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1
Ding, Yuxiao, Bingsen Zhang, Neeraj Gupta, and Dang Sheng Su. "Heterogenization of homogenous reaction system on carbon surface with ionic liquid as mediator." Green Chemistry 17, no. 2 (2015): 1107–12. http://dx.doi.org/10.1039/c4gc01814a.
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Mootz, Dietrich, and Jörg Hocken. "Das System Pyridin-Chlorwasserstoff: Bildung und Struktur kristalliner Addukte / The System Pyridine-Hydrogen Chloride: Formation and Structure of Crystalline Adducts." Zeitschrift für Naturforschung B 44, no. 10 (1989): 1239–46. http://dx.doi.org/10.1515/znb-1989-1017.
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The melting diagram of the system pyridine-hydrogen chloride was determined by DTA. It reveals the existence of intermediary solid complexes pyridine · xHCl with x = 0.5, 1, 2, 4 and 6. The structures of those with x = 1 (room-temperature phase), 2, 4 and 6 were determined from single-crystal MoKa diffractometer data at low temperatures. Pyridinium and chloride ions and, with the exception of the mono-adduct, hydrogen chloride molecules are hydrogen-bonded into various discrete molecular and complex-ionic structural units. Among these are the first poly-(hydrogen chloride) anions, HnCln+1- or [Cl(HCl)n]- with n > 1 (viz. n = 2, 4 and 5), characterized by crystal structure analysis.
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Erdmenger, Tina, Renzo M. Paulus, Richard Hoogenboom, and Ulrich S. Schubert. "Scaling-up the Synthesis of 1-Butyl-3-methylimidazolium Chloride under Microwave Irradiation." Australian Journal of Chemistry 61, no. 3 (2008): 197. http://dx.doi.org/10.1071/ch07345.
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Ionic liquids are considered to be ‘green’ solvents on account of their non-volatility and non-flammability – which are results of their negligible vapour pressures – as well as reusability. On the basis of ecological concerns, ionic liquids seem to be an attractive alternative to conventional volatile organic solvents. In the present work, the reaction conditions for the synthesis of 1-butyl-3-methylimidazolium chloride were optimized on a small scale (~2 mL, 10 mmol) using a single-mode microwave system. The conditions obtained were subsequently transferred to various microwave reactors, both batch and continuous flow, as well as mono-mode and multi-mode, for the direct scale-up of the synthesis from 0.01 to 1.15 mol.
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Faizullozoda, Erkin. "The study of hydroxyl complexation processes in Fe(III)–Fe(II)–Na(H)CI–H2O system." E3S Web of Conferences 401 (2023): 05044. http://dx.doi.org/10.1051/e3sconf/202340105044.
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Hydroxyl complexation in the Fe(III)–Fe(II)–Na(H)CI-H2O system at different ionic strengths of the solution, temperature 308.16 K, was studied by the Clark–Nikolsky oxidation potential method. The formation of the following mono- and binuclear coordination compounds is shown [Fe(OH)(H2O)5]2+; [Fe2(OH)2(H2O)10]4+; [Fe(OH)2(H2O)4]+ ; [Fe(OH)3(H2O)3]0. It was found that Fe(II) does not form hydroxo complexes at the studied concentration parameters, and the pH range from 1.0 to 3.0. Above this pH value, Fe(III) hydrolyzes and forms a brown precipitate.
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Kazmi, Bilal, Syed Imran Ali, and Zahoor Ul Hussain Awan. "Exergy-based sustainability analysis of biogas upgrading using a hybrid solvent (imidazolium-based ionic liquid and aqueous monodiethanolamine)." Biofuel Research Journal 10, no. 1 (2023): 1774–85. http://dx.doi.org/10.18331/brj2023.10.1.3.
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Energy may be generated in large quantities from fossil fuels, but this comes with environmental concerns. Thus, renewable resources like biogas, comprising carbon dioxide and methane, should be used alone or in combination with fossil fuels to mitigate the environmental footprints of energy generation systems. In this study, a new concept of hybrid solvent was presented, which combines 1-octyl-3-methylimidazolium tetrafluoroborate with aqueous mono diethanolamine for biogas upgrading process to provide high purity (≥ 99 wt%) and recovery (≥ 99 wt%) of biomethane. The process was simulated in ASPEN Plus® V.11. The thermodynamic framework was validated against experimental data, and rigorous regression was conducted to obtain binary parameters. To establish the efficacy of the suggested hybrid solvent, three scenarios were studied by altering the concentration of ionic liquid (5–20 wt%) linked with amine and compared to aqueous mono diethanolamine as the base case (50 wt%). The results showed that a hybrid solvent with 5 wt% 1-octyl-3-methylimidazolium tetrafluoroborate could increase CH4 purity to 99% (mol%). The hybrid solvent led to an energy saving of 64.94% compared to the amine-based system. Thermodynamic irreversibilities showed that 5 wt% 1-octyl-3-methylimidazolium tetrafluoroborate improved exergy efficiency by 54% over the amine-based procedure. Environmentally, the hybrid solvent system also achieved a higher capture rate (99%) and lower emissions (0.017 kW/kmol). Comparing the economic prospects, 5 wt% 1-octyl-3-methylimidazolium tetrafluoroborate saved 56% on total capital cost, making it competitive from an investment perspective.
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Filho, Juvenal C. S., Antonio G. Ferreira, Maria Carolina A. F. Gotardo, and Marilda das Dores Assis. "Mono-crowned substituded iron porphyrin: synthesis, analytical properties and catalytic activity." Journal of Porphyrins and Phthalocyanines 09, no. 09 (2005): 637–45. http://dx.doi.org/10.1142/s1088424605000745.
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A substituted porphyrin bearing a crown ether unit, H 2( M 18 C 6 P ), was synthesized from the reaction between (5-mono(o-aminophenyl)10,15,20-triphenylporphyrin) and the acyl derivative of the ether (4-carboxy-18-crown-6). The corresponding iron porphyrin, Fe ( M 18 C 6 P ) Cl , was obtained through iron insertion into H 2( M 18 C 6 P ). The new free-base porphyrin was analyzed by C , N , and H elemental analysis, UV-vis and IR spectroscopies, electrospray mass spectrometry (MS) and 1 H NMR. It selectively extracts 18% of the K + ions present in aqueous medium to the organic phase (chloroform). UV-vis spectroscopy studies showed that H 2( M 18 C 6 P ) is also capable of forming aggregates with K +, probably the 1:1 complex, in methanol. This happens because the ionic radius of the potassium ion is appropriate for its accommodation inside the cavity of the crown ether, and also because of the associative effect between the porphyrin and the crown ether unit. The iron porphyrin Fe ( M 18 C 6 P ) Cl was used as catalyst for the epoxidation of cyclooctene by iodosylbenzene or sodium hypochlorite, in methanol or biphasic water/dichloroethane system, respectively. The results obtained with sodium hypochlorite show that Fe ( M 18 C 6 P ) Cl is a potential catalyst for selective oxidations, because the crown ether unit can select or orient substrates. This iron porphyrin can also be employed as a catalyst in a biphasic water/organic solvent system, with no need of a phase transfer agent.
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Gigliuto, Antonio, Rosalia Maria Cigala, Anna Irto, et al. "The Solution Behavior of Dopamine in the Presence of Mono and Divalent Cations: A Thermodynamic Investigation in Different Experimental Conditions." Biomolecules 11, no. 9 (2021): 1312. http://dx.doi.org/10.3390/biom11091312.
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The interactions of dopamine [2-(3,4-Dihydroxyphenyl)ethylamine, (Dop−)] with methylmercury(II) (CH3Hg+), magnesium(II), calcium(II), and tin(II) were studied in NaCl(aq) at different ionic strengths and temperatures. Different speciation models were obtained, mainly characterized by mononuclear species. Only for Sn2+ we observed the formation of binuclear complexes (M2L2 and M2LOH (charge omitted for simplicity); M = Sn2+, L = Dop−). For CH3Hg+, the speciation model reported the ternary MLCl (M = CH3Hg+) complex. The dependence on the ionic strength of complex formation constants was modeled by using both an extended Debye–Hückel equation that included the Van’t Hoff term for the calculation of enthalpy change values of the formation and the Specific Ion Interaction Theory (SIT). The results highlighted that, in general, the entropy is the driving force of the process. The sequestering ability of dopamine towards the investigated cations was evaluated using the calculation of pL0.5 parameter. The sequestering ability trend resulted to be: Sn2+ > CH3Hg+ > Ca2+ > Mg2+. For example, at I = 0.15 mol dm−3, T = 298.15 K and pH = 7.4, pL0.5 = 3.46, 2.63, 1.15, and 2.27 for Sn2+, CH3Hg+, Ca2+ and Mg2+ (pH = 9.5 for Mg2+), respectively. For the Ca2+/Dop− system, the precipitates collected at the end of the potentiometric titrations were analyzed by thermogravimetry (TGA). The thermogravimetric calculations highlighted the formation of solid with stoichiometry dependent on the different metal:ligand ratios and concentrations of the starting solutions.
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Chen, Jin-Yan, Imdad Kaleem, Dong-Mei He, Gui-Yan Liu та Chun Li. "Efficient production of glycyrrhetic acid 3-O-mono-β-d-glucuronide by whole-cell biocatalysis in an ionic liquid/buffer biphasic system". Process Biochemistry 47, № 6 (2012): 908–13. http://dx.doi.org/10.1016/j.procbio.2011.10.024.
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Janusz, Wladyslaw, Anita Sędłak, and Marlena Matysek-Nawrocka. "Experimental Study of the Co-Adsorption of Cadmium and Citrate Ions onto a TiO2 (Anatase)/Electrolyte Solution Interface." Adsorption Science & Technology 26, no. 8 (2008): 599–612. http://dx.doi.org/10.1260/026361708788059875.
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A study of the co-adsorption of cadmium and citrate ions onto the mono-dispersed TiO2 (anatase)/NaClO4 aqueous solution interface is presented. The influence of ionic strength and pH on the adsorption of cadmium and citrate ions in this system was investigated. The surface charge density, the ζ-potential and adsorption-edge (or envelope) parameters such as pH50% and ΔpH10–90% were also determined for different concentrations of adsorbed ions. The presence of citrate anions increased the adsorption of Cd(II) ions at low pH values but led to a corresponding decrease at high pH values. The influence of pH on the shapes of the corresponding adsorption isotherms for citrate anions was characteristic of that for anion adsorption onto metal oxides; this is referred to as the “adsorption envelope”.
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Singh, Himanshi, Sugam Kumar, and Vinod K. Aswal. "Interplay of interactions in nanoparticle–surfactant complexes in aqueous salt solution." Journal of Applied Physics 132, no. 22 (2022): 224701. http://dx.doi.org/10.1063/5.0118615.
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The evolution of phase behavior and interactions in anionic silica nanoparticles (Ludox HS40), surfactants [non-ionic decaethylene glycol mono-dodecyl ether (C12E10) and anionic sodium dodecyl sulfate (SDS)], and nanoparticle–surfactant solutions in the presence of salt (NaCl) has been studied using small-angle neutron scattering and dynamic light scattering. In an anionic silica nanoparticle solution (1 wt. %), the phase behavior is controlled by salt concentrations (0–1 M) through screening electrostatic interactions. In the case of 1 wt. % surfactant solutions, the anionic SDS surfactant micelles show significant growth upon adding salt, whereas non-ionic surfactant C12E10 micelles remain spherical until a high salt concentration (1 M). In the mixed system of HS40–C12E10, a transition from a highly stable transparent phase to a two-phase turbid system is observed with a small amount of salt addition CS* (∼0.06 M). The single transparent phase of this system corresponds to sterically stabilized micelles-decorated nanoparticles. For the turbid phase, the results are understood in terms of depletion attraction induced by non-adsorption of C12E10 micelles, which explains the appearance of turbidity at a much lower concentration of salt. In the mixed system of similarly charged nanoparticles and micelles (HS40-SDS), the phase behavior is governed by no physical interaction between the components, and salt screens the repulsive interaction among nanoparticles. These results are further utilized to tune multicomponent interactions and phase behavior of nanoparticles with a mixed C12E10-SDS surfactant system in the presence of salt. The mixed surfactants provide tuning of nanoparticle–micelle as well as micelle–micelle interactions to dictate the phase behavior of a nanoparticle–surfactant solution. In these systems, the effective potential can be described by double-Yukawa potential taking account of attractive and repulsive parts at low and intermediate salt concentrations (<CS*). At high salt concentrations (>CS*), the aggregation of nanoparticles is characterized by fractal aggregates.
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Kim, Nari, Calvin C. H. Cheng, and M. Cynthia Goh. "Universal aqueous synthesis of ultra-small polymer-templated nanoparticles: synthesis optimization methodology for counterion-collapsed poly(acrylic acid)." Canadian Journal of Chemistry 96, no. 1 (2018): 44–50. http://dx.doi.org/10.1139/cjc-2017-0444.
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A long polyelectrolyte chain collapses into a nano-sized particle upon the addition of counterions under appropriate solution conditions. This phenomenon forms the basis for a simple universal method for aqueous synthesis of ultra-small (<10 nm) metal, metal oxide, and other types of nanoparticles in the following manner: the counterion-collapsed polyelectrolyte chains are made stable by crosslinking, effectively trapping the counterions, which are subsequently chemically modified, to form metal nanoparticles via reduction or metal oxides nanoparticles via oxidation, within the collapsed polymer nanoparticle. This highly versatile platform methodology can be applied to almost any polyelectrolyte–counterion pair, making possible the rapid development of syntheses of different nanoparticles within the same chemical environment. Using poly(acrylic acid) as a model system, a methodology for the optimization of conditions for the polyelectrolyte collapse by various mono- and multi-valent metal cations is developed. The optimal counterion concentration did not correlate with ionic strength and metal ion valency and was highly variable from system to system. By monitoring the polyelectrolyte conformation using viscosity and turbidity measurements, the appropriate metal ion concentration for each nanoparticle system was determined.
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Li, Yunlei, Yanjie Zhang, Panfeng Wu, Caiting Feng, and Ganglin Xue. "Catalytic Oxidative/Extractive Desulfurization of Model Oil using Transition Metal Substituted Phosphomolybdates-Based Ionic Liquids." Catalysts 8, no. 12 (2018): 639. http://dx.doi.org/10.3390/catal8120639.
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Polyoxometalates based ionic liquids (POM-ILs) exhibit a high catalytic activity in oxidative desulfurization. In this paper, four new POM-IL hybrids based on transition metal mono-substituted Keggin-type phosphomolybdates, [Bmim]5[PMo11M(H2O)O39] (Bmim = 1-butyl 3-methyl imidazolium; M = Co2+, Ni2+, Zn2+, and Mn2+), have been synthesized and used as catalysts for the oxidation/extractive desulfurization of model oil, in which ILs are used as the extraction solvent and H2O2 as an oxidant under very mild conditions. The factors that affected the desulfurization efficiency were studied and the optimal reaction conditions were obtained. The results showed that the [Bmim]5[PMo11Co(H2O)O39] catalyst demonstrated the best catalytic activity, with sulfur-removal of 99.8%, 85%, and 63% for dibenzothiophene (DBT), 4,6-dimethyldibenzothiophene (4,6-DMDBT), and benzothiophene (BT), respectively, in the case of extraction combining with a oxidative desulfurization system under optimal reaction conditions (5 mL model oil (S content 500 ppm), n(catalyst) = 4 μmol, n(H2O2)/n(Substrate) = 5, T = 50 °C for 60 min with [Omim]BF4 (1 mL) as the extractant). The catalyst can be recycled at least 8 times, and still has stability and high catalytic activity for consecutive desulfurization. Probable reaction mechanisms have been proposed for catalytic oxidative/extractive desulfurization.
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Robertson, Lily A., and Douglas L. Gin. "Effect of an n-Alkoxy-2,4-hexadiene Polymerizable Tail System on the Mesogenic Properties and Cross-Linking of Mono-Imidazolium-Based Ionic Liquid Crystal Monomers." ACS Macro Letters 5, no. 7 (2016): 844–48. http://dx.doi.org/10.1021/acsmacrolett.6b00315.
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He, Dong-Mei, Imdad Kaleem, Si-Ying Qin, Da-Zhang Dai, Gui-Yan Liu та Chun Li. "Biosynthesis of glycyrrhetic acid 3-O-mono-β-d-glucuronide catalyzed by β-d-glucuronidase with enhanced bond selectivity in an ionic liquid/buffer biphasic system". Process Biochemistry 45, № 12 (2010): 1916–22. http://dx.doi.org/10.1016/j.procbio.2010.03.015.
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Kuma, Kenshi, Akira Usui, William Paplawsky, Benjamin Gedulin, and Gustaf Arrhenius. "Crystal structures of synthetic 7 Å and 10 Å manganates substituted by mono- and divalent cations." Mineralogical Magazine 58, no. 392 (1994): 425–47. http://dx.doi.org/10.1180/minmag.1994.058.392.08.
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AbstractThe crystal structures of synthetic 7 Å and 10 Å manganates, synthetic birnessite and buserite, substituted by mono- and divalent cations were investigated by X-ray and electron diffractions. The monoclinic unit cell parameters of the subcell of lithium 7 Å manganate, which is one of the best ordered manganates, were obtained by computing the X-ray powder diffraction data: a = 5.152 Å, b = 2.845 Å, c = 7.196 Å, β = 103.08°. On the basis of the indices obtained by computing the X-ray diffraction data of Li 7 Å manganate, monovalent Na, K and Cs and divalent Be, Sr and Ba 7 Å manganates were interpreted as the same monoclinic structure with β = 100–103° as that of Li 7 Å manganate, from their X-ray diffraction data. In addition, divalent Mg, Ca and Ni 10 Å manganates were also interpreted as the same monoclinic crystal system with β = 90–94° The unit cell parameters, especially a, c and β, change possibly with the type of substituent cation probably because of the different ionic radius, hydration energy and molar ratio of substituent cation to manganese. However, these diffraction data, except for those of Sr and Ba 7 Å and Ca and Ni 10 Å manganates, reveal only some parts of the host manganese structure with the edge-shared [MnO6] octahedral layer. On the other hand, one of the superlattice reflections observed in the electron diffractions was found in the X-ray diffraction lines for heavier divalent cations Sr and Ba 7 Å and Ca and Ni 10 Å manganates. The reflection presumably results from the substituent cation position in the interlayer which is associated with the vacancies in the edge-shared [MnO6] layer and indicates that the essential vacancies are linearly arranged parallel to the b-axis. Furthermore, the characteristic superlattice reflection patterns for several cations, Li, Mg, Ca, Sr, Ba and Ni, manganates were interpreted that the substituent cations are regularly distributed in the interlayer according to the exchange percentage of substituent cation to Na+. In contrast, the streaking in the a-direction observed strongly in the electron diffractions for heavier monovalent cations, K and Cs, manganates probably results from the disordering of their cations in the a-direction in the interlayer.
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Di Pietro, Sebastiano, Vittorio Bordoni, Andrea Mezzetta та ін. "Remarkable Effect of [Li(G4)]TFSI Solvate Ionic Liquid (SIL) on the Regio- and Stereoselective Ring Opening of α-Gluco Carbasugar 1,2-Epoxides". Molecules 24, № 16 (2019): 2946. http://dx.doi.org/10.3390/molecules24162946.
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Carba analogues of biologically relevant natural carbohydrates are promising structures for the development of future drugs endowed with enhanced hydrolytic stability. An open synthetic challenge in this field is the optimization of new methodologies for the stereo- and regioselective opening of α-gluco carbasugar 1,2-epoxides that allow for the preparation of pseudo mono- and disaccharides of great interest. Therefore, we investigated the effect of Lewis acids and solvate ionic liquids (SILs) on the epoxide ring opening of a model substrate. Of particular interest was the complete stereo- and regioselectivity, albeit limited to simple nucleophiles, toward the desired C(1) isomer that was observed using LiClO4. The results obtained with SILs were also remarkable. In particular, Li[NTf2]/tetraglyme ([Li(G4)]TFSI) was able to function as a Lewis acid and to direct the attack of the nucleophile preferentially at the pseudo anomeric position, even with a more complex and synthetically interesting nucleophile. The regioselectivity observed for LiClO4 and [Li(G4)]TFSI was tentatively ascribed to the formation of a bidentate chelating system, which changed the conformational equilibrium and ultimately permitted a trans-diaxial attack on C(1). To the best of our knowledge, we report here the first case in which SILs were successfully employed in a ring-opening process of epoxides.
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Weller, Rolf, Michel Legrand, and Susanne Preunkert. "Size distribution and ionic composition of marine summer aerosol at the continental Antarctic site Kohnen." Atmospheric Chemistry and Physics 18, no. 4 (2018): 2413–30. http://dx.doi.org/10.5194/acp-18-2413-2018.
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Abstract. We measured aerosol size distributions and conducted bulk and size-segregated aerosol sampling during two summer campaigns in January 2015 and January 2016 at the continental Antarctic station Kohnen (Dronning Maud Land). Physical and chemical aerosol properties differ conspicuously during the episodic impact of a distinctive low-pressure system in 2015 (LPS15) compared to the prevailing clear sky conditions. The approximately 3-day LPS15 located in the eastern Weddell Sea was associated with the following: marine boundary layer air mass intrusion; enhanced condensation particle concentrations (1400 ± 700 cm−3 compared to 250 ± 120 cm−3 under clear sky conditions; mean ± SD); the occurrence of a new particle formation event exhibiting a continuous growth of particle diameters (Dp) from 12 to 43 nm over 44 h (growth rate 0.6 nm h−1); peaking methane sulfonate (MS−), non-sea-salt sulfate (nss–SO42-), and Na+ concentrations (190 ng m−3 MS−, 137 ng m−3 nss–SO42-, and 53 ng m−3 Na+ compared to 24 ± 15, 107 ± 20, and 4.1 ± 2.2 ng m−3, respectively, during clear sky conditions); and finally an increased MS− ∕ nss–SO42- mass ratio βMS of 0.4 up to 2.3 (0.21 ± 0.1 under clear sky conditions) comparable to typical values found at coastal Antarctic sites. Throughout the observation period a larger part of MS− could be found in super-micron aerosol compared to nss–SO42-, i.e., (10 ± 2) % by mass compared to (3.2 ± 2) %, respectively. On the whole, under clear sky conditions aged aerosol characterized by usually mono-modal size distributions around Dp= 60 nm was observed. Although our observations indicate that the sporadic impacts of coastal cyclones were associated with enhanced marine aerosol entry, aerosol deposition on-site during austral summer should be largely dominated by typical steady clear sky conditions.
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Maya, Gustavo, Aurora L. Carreño Otero, Fabián L. Monares Bueno, et al. "Rock–Oil–Brine Dominant Mechanisms in Smart Water Flooding." Energies 16, no. 4 (2023): 2043. http://dx.doi.org/10.3390/en16042043.
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Recent research has highlighted wettability alteration as the main consequence of the different mechanisms involved in technologies such as adjusted brine composition water flooding (ABCW) and low-salinity water flooding (LSW). However, studies are still needed to give a phenomenological explanation, and the most influential components of the system (rock–oil–brine) must be clarified. This work focuses on determining the most relevant variables for the smart water effects to occur. Static (contact angles) and dynamic tests (coreflooding) were conducted. For the static tests, aged Berea slices, a specific crude oil (27° API, 10.5 cp at 60 °C), and mono and divalent inorganic salts (Na+, K+, Ca2+, and Mg2+/Cl−) were used in 3 different concentrations of 1000, 3000, and 5000 ppm (ionic strength variation between 0.015 and 0.06) to establish the wettability state by measuring the contact angles of the system. When salts containing chloride were evaluated, a decrease in oil wettability was observed at 5000 ppm. At 3000 and 1000 ppm, tendencies depended on the particular cation. Three brines were selected from the contact angle experiments to be used in coreflooding assays, considering a particular design to identify ion exchange from the rock–oil–brine system. The first assay was carried out in the absence of crude oil as a baseline to determine the ion exchange between the brine and the rock, and a second test considered crude oil to provide insight into ion exchange and its effect on displacement efficiency. Capillary electrophoresis was used in this research as a novel contribution to the systematic study of oil displacement tests, and it has proven to be a powerful tool for understanding the mechanisms involved. The results show that the variations in the concentrations detected in the displacement effluents were the product of the interactions between rock, oil, and brine since the concentrations measured in the absence of oil phase were comparable to those in the injection brine. Significant variations in the effluent ion concentrations were determined for the different brines used, and increases in the pressure differentials were observed for the KCl and CaCl2 brines. These results suggest that the oil–brine ion exchange (salting in/out) represents a relevant mechanism to explain the observed displacement efficiencies and differential pressures. The ionic enrichment of the water phase due to the salting in/out effect needs to be better understood.
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Abbott, JohnPaul R., Heping Zhu, and Hongyoung Jeon. "Retention and Spread Capability of Impacted Droplets with Surfactant and Hydrocolloid Based Adjuvants." Transactions of the ASABE 64, no. 6 (2021): 1883–94. http://dx.doi.org/10.13031/trans.14461.
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HighlightsRetention and spread of droplets with seven adjuvants were investigated on flat leaves.Surface tension of spray solutions, leaf wettability, and roughness strongly affected droplet retention and spread.Complete droplet retention occurred on hydrophilic leaves with all adjuvants and concentrations.High retention and spread on superhydrophobic leaves were achieved with the organo-silicone adjuvant.No retention occurred on superhydrophobic leaf surfaces with the hydrocolloid polymer adjuvant.Abstract. To optimize spray application efficiency, it is necessary to understand how the addition of adjuvants modifies the deposition properties of spray droplets on leaf surfaces due to variations in adhesive characteristics, such as roughness and wettability. Retention and spread of droplets with seven commercially available adjuvants were tested and compared at different concentrations. Tests were conducted with three leaf surfaces ranging in roughness and wettability from very smooth and hydrophilic to very rough and superhydrophobic. The adjuvants were formulated with non-ionic surfactant, crop oil, seed oil, organo-silicone, hydrocolloid polymer, or combinations of these agents as primary ingredients. Droplets of approximately 340 µm diameter were emitted from a streamed mono-sized generator. Droplet impact and spread were recorded with a 3D imaging system consisting of three high-speed digital cameras and analyzed using 3D motion analysis software. Retention and spread were determined by comparing droplet liquid volumes and droplet cross-sectional areas before and after impact, respectively. The surface tension of spray solutions and wettability of leaf surfaces strongly affected droplet retention. Droplets with lower surface tension were more likely to achieve high retention than those with higher surface tension. Droplet retention generally decreased with increasing leaf roughness-wettability. All droplets with and without adjuvants achieved 100% retention on the hydrophilic leaf surface. Addition of non-ionic, oil, or organo-silicone based adjuvants in the spray solution improved droplet retention on hydrophobic leaves, while the organo-silicone based adjuvant achieved the highest retention on superhydrophobic leaf surfaces. Droplet retention with the hydrocolloid polymer adjuvant was generally comparable to the other six adjuvants on the hydrophilic leaves and on the hydrophobic leaves with intermediate roughness and wettability but failed to achieve any retention on the superhydrophobic leaves. To improve droplet retention and adhesion, selection of adjuvants representing the non-ionic, oil, organo-silicone, blended, or hydrocolloid-based additives for enhancing spray solution performance must comply with the leaf surface characteristics. Keywords: Droplet rebound, High-speed imaging, Leaf wettability, Pesticide droplet deposition, Topography parameters.
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Wang, Yao, Zhi Zhang, Qun Chen, et al. "A Novel Modification of Copper (II) Phthalocyanine Particles towards Electrophoretic Displays." Micromachines 13, no. 6 (2022): 880. http://dx.doi.org/10.3390/mi13060880.
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Electrophoretic display (EPD) is a popular display technology in recent years. The core of the EPD is electrophoretic particles, and its Zeta potential has an important impact on EPDs. In this work, a method using pyrrolidine mono ionic liquid was proposed to improve the Zeta potential of electrophoretic particles: Copper (II) phthalocyanine pigment was modified with mono ionic liquid 1-Butyl-1-methylpyrrolidinium bromide. The characterization results show that the mono ionic liquid had been successfully coated on pigment particles. At the same time, the dispersion and stability of particles were improved. The modified Copper (II) phthalocyanine pigment could be stably dispersed in tetrachloroethylene for more than 20 days. The Zeta potential increased from 32.42 mV to 49.91 mV, increasing by 53.95%. Finally, the prepared blue electrophoretic particles were compounded with white titanium dioxide to prepare blue and white dual-color electrophoretic dispersion, and then an EPD cell was designed to test its performance. The results show that the prepared electrophoretic dispersion can realize reversible reciprocating motion. Therefore, because of the unique structure and properties of pyrrolidine mono ionic liquids, the blue nanoparticles prepared with pyrrolidine ionic liquids as charge control agents in this study can be used as excellent candidate materials for EPD.
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Zhang, Zhi, Yao Wang, Qun Chen, et al. "Application of High Potential Electrophoretic Particles Modified with High Ionization Mono Ionic Liquid for Electrophoretic Displays." Micromachines 13, no. 8 (2022): 1235. http://dx.doi.org/10.3390/mi13081235.
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The electrophoretic display (EPD) has attracted widespread attention due to its great visual perception, energy-saving, portability, and bistability. However, the EPD still has many problems in response time, colorization, etc., which limits its practical application. In this paper, novel blue electrophoretic particles were prepared with copper (II) phthalocyanine and high ionization 1-butyl-1-methyl piperidinium bromide mono ionic liquid. It was shown that electrophoretic particles dispersed in a non-polar tetrachloroethylene medium had high Zeta potential and electrophoretic mobility. At the same time, electrophoretic particles showed better dispersion stability. Finally, the prepared blue electrophoretic particles and white titanium dioxide particles were compounded to prepare blue and white dual-color electrophoretic dispersion. An EPD cell was made to test its performance. The results showed that the prepared blue and white dual-color electrophoretic dispersion could realize a reversible response. Piperidine mono ionic liquid increased the surface potential of copper (II) phthalocyanine from +30.50 mV to +60.27 mV, enhancing it by 97.61%. Therefore, we believed that modifying particles with high ionization mono ionic liquid had great applicability to the modification of electrophoretic particles, and blue particles prepared with piperidine mono ionic liquid as a charge control agent (CCA) were excellent candidates for EPDs.
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Ricciardi, Luca, Willem Verboom, Jean-Paul Lange, and Jurriaan Huskens. "Kinetic model for the dehydration of xylose to furfural from a boronate diester precursor." RSC Advances 12, no. 49 (2022): 31818–29. http://dx.doi.org/10.1039/d2ra06898b.
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The dehydration kinetics of xylose from its boronate diester is modeled. Insight is provided into the effects of solvent polarity, ionic strength, phase partitioning and mixing, in both mono and biphasic systems.
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Pandey, Mayank, Girish M. Joshi, and Anji Reddy Polu. "Electrical performance of soft polymer ionic membranes with mono and multi polymer systems." Karbala International Journal of Modern Science 1, no. 4 (2015): 194–99. http://dx.doi.org/10.1016/j.kijoms.2015.10.009.
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Selva, Maurizio, Alvise Perosa, Sandro Guidi, and Lisa Cattelan. "Ionic liquids as transesterification catalysts: applications for the synthesis of linear and cyclic organic carbonates." Beilstein Journal of Organic Chemistry 12 (August 26, 2016): 1911–24. http://dx.doi.org/10.3762/bjoc.12.181.
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The use of ionic liquids (ILs) as organocatalysts is reviewed for transesterification reactions, specifically for the conversion of nontoxic compounds such as dialkyl carbonates to both linear mono-transesterification products or alkylene carbonates. An introductory survey compares pros and cons of classic catalysts based on both acidic and basic systems, to ionic liquids. Then, innovative green syntheses of task-specific ILs and their representative applications are introduced to detail the efficiency and highly selective outcome of ILs-catalyzed transesterification reactions. A mechanistic hypothesis is discussed by the concept of cooperative catalysis based on the dual (electrophilic/nucleophilic) activation of reactants.
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Tinker, A., and A. J. Williams. "Probing the structure of the conduction pathway of the sheep cardiac sarcoplasmic reticulum calcium-release channel with permeant and impermeant organic cations." Journal of General Physiology 102, no. 6 (1993): 1107–29. http://dx.doi.org/10.1085/jgp.102.6.1107.
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The sarcoplasmic reticulum Ca(2+)-release channel plays a central role in cardiac muscle function by providing a ligand-regulated pathway for the release of sequestered Ca2+ to initiate contraction following cell excitation. The efficiency of the channel as a Ca(2+)-release pathway will be influenced by both gating and conductance properties of the system. In the past we have investigated conduction and discrimination of inorganic mono- and divalent cations with the aim of describing the mechanisms governing ion handling in the channel (Tinker, A., A.R. G. Lindsay, and A.J. Williams. 1992. Journal of General Physiology. 100:495-517.). In the present study, we have used permeant and impermeant organic cations to provide additional information on structural features of the conduction pathway. The use of permeant organic cations in biological channels to explore structural motifs underlying selectivity has been an important tool for the electrophysiologist. We have examined the conduction properties of a series of monovalent organic cations of varying size in the purified sheep cardiac sarcoplasmic reticulum Ca(2+)-release channel. Relative permeability, determined from the reversal potential measured under bi-ionic conditions with 210-mM test cation at the cytoplasmic face of the channel and 210 mM K+ at the luminal, was related inversely to the minimum circular cation radius. The reversal potential was concentration-independent. The excluded area hypothesis, with and without a term for solute-wall friction, described the data well and gave a lower estimate for minimum pore radius of 3.3-3.5 A. Blocking studies with the impermeant charged derivative of triethylamine reveal that this narrowing occurs over the first 10-20% of the voltage drop when crossing from the lumen of the SR to the cytoplasm. Single-channel conductances were measured in symmetrical 210 mM salt. Factors other than relative permeability determine conductance as ions with similar relative permeability can have widely varying single-channel conductance. Permeant ions, such as the charged derivatives of trimethylamine and diethylmethylamine, can also inhibit K+ current. The reduction in relative conductance with increasing concentrations of these two ions at a holding potential of 60 mV was described by a rectangular hyperbola and revealed higher affinity binding for diethylmethylamine as compared to trimethylamine. It was possible to describe the complex permeation properties of these two ions using a single-ion four barrier, three binding site Eyring rate theory model. In conclusion, these studies reveal that the cardiac Ca(2+)-release channel has a selectivity filter of approximately 3.5-A radius located at the luminal face of the protein.(ABSTRACT TRUNCATED AT 400 WORDS)
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Priyanka, V. P., and Ramesh L. Gardas. "Mono- and di- cationic ionic liquids based aqueous biphasic systems for the extraction of diclofenac sodium." Separation and Purification Technology 234 (March 2020): 116048. http://dx.doi.org/10.1016/j.seppur.2019.116048.
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Orysyk, Svitlana, Vasyl Pekhnyo, Viktor Orysyk, Yuri Zborovskii, Polina Borovyk, and Vovk Mykhailo. "FUNDAMENTAL ASPECTS OF THE COORDINATION CHEMISTRY OF TRANSITION METALS WITH FUNCTIONALLY SUBSTITUTED THIOAMIDES (PART 1)." Ukrainian Chemistry Journal 88, no. 2 (2022): 85–115. http://dx.doi.org/10.33609/2708-129x.88.02.2022.85-115.
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The influence of competitive coordination, a tautomeric form of functionally substituted thioamides, conditions of synthesis and nature of the metal on the course of the reaction and structure of mono-, bi, and polynuclear complexes of 3d, 4d-metals is considered based on results obtained in the Department of "Chemistry of Complex Compounds" of the V.I. Vernadsky Institute of General and Inorganic Chemistry NAS of Ukraine, together with the staff of the Department of “Chemistry of Heterocyclic Compounds” of the Institute of Organic Chemistry NAS of Ukraine.
 The influence of ligand denticity, as well as conditions of complex formation on the structure of obtained complexes and their polymorphic modifications, was studied based on the reaction of d-metals with functionally substituted N, S- and O, N, S-containing thioamides. In addition, it is proved the influence of tautomeric forms of thioamides on the stereochemistry of coordination polyhedra: it is found that the thionic tautomeric form promotes the transposition of thioureas, while the thiol form promotes its cis-position in the square-planar of a polyhedron of 3d, 4d-metals in the structure of complexes. However, it was found that the thion tautomeric form leads to the formation of octahedral, while the thiol form to the square-planar of coordination nodes in complexes of Cu(II) and Ni(II), which are characterized by a change in coordination polyhedra (from square-planar and tetrahedron to octahedron) that depending on the strength of the ligand field. It is obvious that this effect of tautomeric forms of thioamides is associated with the formation of a conjugate system of double bonds in their molecules. In this case, the transition of thioamide to thiol form depends on the pH and the nature of the organic solvent: in a weakly alkaline medium or polar organic solvent (pyridine, chloroform) there is a shift of equilibrium towards to the dominance of thiol tautomeric form.
 It was found that the thionic tautomeric form of thioamides (depending on pH and substituent composition) reacts with metal salts mainly in neutral form or in the monoanionic form, forming complexes of molecular or ionic nature, while thiol form reacts in the form of dianion, forming complexes preferably anionic type. Ionic compounds are usually soluble or sparingly soluble in water in low concentrations (10-3–10-5 mol/l), while compounds of the molecular type are soluble only in DMSO and DMF.
 It is shown that the stereoselective synthesis of various ligand complexes is carried out mainly in three ways: 1) by the interaction of the initial components in the corresponding stoichiometry. In this case, the vacancy in the metal environment is occupied by either the anions of the starting metal salt (Hal-, SO42-, NO3-, CH3COO-, etc.) or other organic molecules (triphenylphosphine, pyridine, etc.); 2) carrying out parallel reactions (hydrolysis and oxidation of thioureas), which lead to participation in the coordination of by-products of the reaction; 3) carrying out reactions with intraligand rearrangements, which leads to the cyclization of organic ligands and coordination of the products of their transformation to the central metal ion. However, it was found that hydrolysis / oxidation or intraligand cyclization of substituted polydentate thioamides can occur both under the action of synthesis conditions and under the action of complexing metals as promoters of organic reactions.
 It was found that depending on the temperature and time of interaction of the starting reagents, different polymorphic modifications of complexes (triclinic or monoclinic) are formed, which differ in packing density and the nature of intermolecular interactions. As a result, such polymorphic modifications have different solubilities in water, which is important for the controlled synthesis of appropriate structures and their practical application.
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Yue, Zheng, Qiang Ma, Xinyi Mei, et al. "Specifically Designed Ionic Liquids—Formulations, Physicochemical Properties, and Electrochemical Double Layer Storage Behavior." ChemEngineering 3, no. 2 (2019): 58. http://dx.doi.org/10.3390/chemengineering3020058.
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Two key features—non-volatility and non-flammability—make ionic liquids (ILs) very attractive for use as electrolyte solvents in advanced energy storage systems, such as supercapacitors and Li-ion batteries. Since most ILs possess high viscosity and are less prone to dissolving common electrolytic salts when compared to traditional electrolytic solvents, they must be formulated with low viscosity thinner solvents to achieve desired ionic conductivity and dissolution of electrolyte salts in excess of 0.5 M concentration. In the past few years, our research group has synthesized several specifically designed ILs (mono-cationic, di-cationic, and zwitterionic) with bis(trifluoromethylsulfonyl)imide (TFSI) and dicyanamide (DCA) as counter anions. This article describes several electrolyte formulations to achieve superior electrolytic properties. The performance of a few representative IL-based electrolytes in supercapacitor coin cells is presented.
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Reza, Jamilur. "Self-Emulsifying Drug Delivery Systems: A Review." International Journal of Pharmaceutical and Life Sciences 2, no. 2 (2013): 80–84. http://dx.doi.org/10.3329/ijpls.v2i2.15453.
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Self-emulsifying drug delivery systems (SEDDS) possess unparalleled potential in improving oral bioavailability of poorly water-soluble or lipophilic drugs. Following their oral administration, these systems rapidly disperse in gastrointestinal fluids, yielding micro- or nanoemulsions containing the solubilized drug. Owing to its miniscule globule size, the micro/nanoemulsified drug can easily be absorbed through lymphatic pathways, bypassing the hepatic first-pass effect. But it has drawbacks as formulation development, quality control, stability etc. These liquid SEDDS can be converted into solid dosage form without affecting drug release property. After administering the drug gets released and self emulsify in the GI tract. Generally solid SEDDS are formed with mono, di or triglycrides of fatty acid, non ionic surfactants and solidifying agents with diluents such as microcrystalline cellulose, lactose etc. DOI: http://dx.doi.org/10.3329/ijpls.v2i2.15453 International Journal of Pharmaceutical and Life Sciences Vol.2(2) 2013: 80-84
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da Silva Filho, Antonio João, Lucinêz da Cruz Dantas, and Otávio Luís de Santana. "Diradicalar Character and Ring Stability of Mesoionic Heterocyclic Oxazoles and Thiazoles by Ab Initio Mono and Multi-Reference Methods." Molecules 25, no. 19 (2020): 4524. http://dx.doi.org/10.3390/molecules25194524.
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Mesoionics are neutral compounds that cannot be represented by a fully covalent or purely ionic structure. Among the possible mesomeric structures of these compounds are the diradical electronic configurations. Theoretical and experimental studies indicate that some mesoionic rings are unstable, which may be related to a significant diradical character, that until then is not quantified. In this work, we investigated the diradical character of four heterocycles: 1,3-oxazol-5-one, 1,3-oxazol-5-thione, 1,3-thiazole-5-one, and 1,3-thiazole-5-thione. The oxazoles are known to be significatively less stable than thiazoles. DFT and ab initio single (B3LYP, MP2, CCSD, and QCISD) and ab initio multi-reference (MR-CISD) methods with three basis sets (6-311+G(d), aug-cc-pVDZ, and aug-cc-pVTZ) were employed to assess the diradical character of the investigated systems, in gas phase and DMSO solvent, from three criteria: (i) HOMO-LUMO energy gap, (ii) determination of energy difference between singlet and triplet wave functions, and (iii) quantification of the most significant diradical character (y0, determined in the unrestricted formalism). All of the results showed that the diradical character of the investigated systems is very small. However, the calculated electronic structures made it possible to identify the possible origin of the oxazoles instability, which can help the design of mesoionic systems with the desired properties.
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Raczyńska, Ewa D. "On Analogies in Proton-Transfers for Pyrimidine Bases in the Gas Phase (Apolar Environment)—Cytosine Versus Isocytosine." Symmetry 15, no. 2 (2023): 342. http://dx.doi.org/10.3390/sym15020342.
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Inter- and intra-molecular proton-transfers between functional groups in nucleobases play a principal role in their interactions (pairing) in nucleic acids. Although prototropic rearrangements (intramolecular proton-transfers) for neutral pyrimidine bases are well documented, they have not always been considered for their protonated and deprotonated forms. The complete isomeric mixtures in acid-base equilibria and in acidity–basicity parameters have not yet been examined. Taking into account the lack of literature and data, research into the question of prototropy for the ionic (protonated and deprotonated) forms has been undertaken in this work. For the purposes of this investigation, two isomeric pyrimidine bases (C—cytosine and iC—isocytosine) were chosen. They exhibit analogous (symmetrical) general acid-base equilibria (intermolecular proton-transfers). Being similar polyfunctional tautomeric systems, C and iC possess two labile protons and five conjugated tautomeric sites. However, positions of exo groups are different. Consequently, structural conversions such as prototropy, rotational, and geometrical isomerism of exo groups (=O/−OH and =NH/−NH2) and their intramolecular interactions with endo groups (=N−/>NH) possible in neutral C and iC and in their ionic forms lead to some differences in compositions of isomeric mixtures. By application of quantum–chemical methods to the isolated (in vacuo) species, stability of all possible neutral and ionic isomers has been examined and the candidate isomers selected. The complete isomeric mixtures have been considered for the first time for di-deprotonated, mono-deprotonated, mono-protonated, and di-protonated forms. Protonation–deprotonation reactions have been analyzed in the gas phase that models non-polar environment. The gas-phase microscopic (kinetic) and macroscopic (thermodynamic) acidity–basicity parameters have been estimated for each step of acid-base equilibria. When proceeding from di-anion to di-cation in four steps of protonation–deprotonation reaction, the macroscopic proton affinities for C and iC differ by less than 10 kcal mol−1. Their DFT-calculated values are as follows: 451 and 457, 340 and 339, 228 and 224, and 100 and 104 kcal mol−1, respectively. Differences between the microscopic proton affinities for analogous isomers of C and iC seem to be larger for the exo than endo groups. Owing to variations of relative stabilities for neutral and ionic isomers, in some cases they are even larger than 10 kcal mol−1.
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Akasofu, Toru, Masanobu Kusakabe, and Shigeru Tamaki. "An interpretation on the thermodynamic properties of liquid Pb–Te alloys." High Temperature Materials and Processes 39, no. 1 (2020): 297–303. http://dx.doi.org/10.1515/htmp-2020-0068.
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AbstractThe bonding character of liquid lead telluride \text{PbTe} is thermodynamically investigated in detail. Its possibility as an ionic melt composed of cation {\text{Pb}}^{2+} and anion {\text{Te}}^{2-} is not acceptable, by comparing the ionization energy of \text{Pb} atom, electron affinity of \text{Te} atom and the ionic bonding energy due to the cation {\text{Pb}}^{2+} and anion {\text{Te}}^{2-} with the help of structural information. Solid lead telluride PbTe as a narrow band gap semiconductor might yield easily the overlapping of the tail of valence band and that of conduction one. And on melting, it becomes to an ill-conditioned metallic state, which concept is supported by the electrical behaviors of liquid Pb–Te alloys observed by the present authors. As structural information tells us about the partial remain of some sorts of covalent-type mono-dipole and poly-dipole of the molecule \text{PbTe}, all systems are thermodynamically explained in terms of a mixture of these molecules and cations {\text{Pb}}^{4+} and {\text{Te}}^{2+} and a small amount of the conduction electrons are set free from these elements based on the ternary solution model.
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Wang, Yanni, Chaowu Dai, Wei Huang та ін. "Density Functional Method Study on the Cooperativity of Intermolecular H-Bonding and π-π+ Stacking Interactions in Thymine-[Cnmim]Br (n = 2, 4, 6, 8, 10) Microhydrates". Molecules 27, № 19 (2022): 6242. http://dx.doi.org/10.3390/molecules27196242.
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The exploration of the ionic liquids’ mechanism of action on nucleobase’s structure and properties is still limited. In this work, the binding model of the 1-alkyl-3-methylimidazolium bromide ([Cnmim]Br, n = 2, 4, 6, 8, 10) ionic liquids to the thymine (T) was studied in a water environment (PCM) and a microhydrated surroundings (PCM + wH2O). Geometries of the mono-, di-, tri-, and tetra-ionic thymine (T-wH2O-y[Cnmim]+-xBr−, w = 5~1 and x + y = 0~4) complexes were optimized at the M06-2X/6-311++G(2d, p) level. The IR and UV-Vis spectra, QTAIM, and NBO analysis for the most stable T-4H2O-Br−-1, T-3H2O-[Cnmim]+-Br−-1, T-2H2O-[Cnmim]+-2Br−-1, and T-1H2O-2[Cnmim]+-2Br−-1 hydrates were presented in great detail. The results show that the order of the arrangement stability of thymine with the cations (T-[Cnmim]+) by PCM is stacking > perpendicular > coplanar, and with the anion (T-Br−) is front > top. The stability order for the different microhydrates is following T-5H2O-1 < T-4H2O-Br−-1 < T-3H2O-[Cnmim]+-Br−-1 < T-2H2O-[Cnmim]+-2Br−-1 < T-1H2O-2[Cnmim]+-2Br−-1. A good linear relationship between binding EB values and the increasing number (x+y) of ions has been found, which indicates that the cooperativity of interactions for the H-bonding and π-π+ stacking is varying incrementally in the growing ionic clusters. The stacking model between thymine and [Cnmim]+ cations is accompanied by weaker hydrogen bonds which are always much less favorable than those in T-xBr− complexes; the same trend holds when the clusters in size grow and the length of alkyl chains in the imidazolium cations increase. QTAIM and NBO analytical methods support the existence of mutually reinforcing hydrogen bonds and π-π cooperativity in the systems.
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Deng, Jie, Jing Li, Zhe Xiao, Shuang Song, and Luming Li. "Studies on Possible Ion-Confinement in Nanopore for Enhanced Supercapacitor Performance in 4V EMIBF4 Ionic Liquids." Nanomaterials 9, no. 12 (2019): 1664. http://dx.doi.org/10.3390/nano9121664.
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Supercapacitors have the rapid charge/discharge kinetics and long stability in comparison with various batteries yet undergo low energy density. Theoretically, square dependence of energy density upon voltage reveals a fruitful but challenging engineering tenet to address this long-standing problem by keeping a large voltage window in the compositionally/structurally fine-tuned electrode/electrolyte systems. Inspired by this, a facile salt-templating enables hierarchically porous biochars for supercapacitors filled by the high-voltage ionic liquids (ILs). Resultant nanostructures possess a coherent/interpenetrated framework of curved atom-thick sidewalls of 0.8-/1.5-nanometer pores to reconcile the pore-size-dependent adlayer structures of ILs in nanopores. Surprisingly, this narrow dual-model pore matches ionic radii of selected ILs to accommodate ions by unique coupled nano-/bi-layer nanoconfinements, augmenting the degree of confinement (DoC). The high DoC efficiently undermines the coulombic ordering networks and induces the local conformational oscillations, thus triggering an anomalous but robust charge separation. This novel bi-/mono-layer nanoconfinement combination mediates harmful overscreening/overcrowding effects to reinforce ion-partitioning, mitigating long-lasting conflicts of power/energy densities. This interesting result differs from a long-held viewpoint regarding the sieving effect that ion-in-pore capacitance peaks only if pore size critically approaches the ion dimension. Optimal biocarbon finally presents a very high/stable operational voltage up to 4 V and specific energy/power rating (88.3 Whkg−1 at 1 kWkg−1, 47.7 Whkg−1 albeit at a high battery-accessible specific power density of 20 kWkg−1), overwhelmingly outperforming most hitherto-reported supercapacitors and some batteries. Such attractive charge storage level can preliminarily elucidate an alternative form of a super-ionic-state high-energy storage linked with both the coordination number and coulombic periodism of the few ion-sized mesopores inside carbon electrodes, escalating supercapacitors into a novel criterion of charge delivery.
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Dubrovskii, Alexey V., Aleksandr L. Kim, Egor V. Musin, and Sergey A. Tikhonenko. "A Study of the Buffer Capacity of Polyelectrolyte Microcapsules Depending on Their Ionic Environment and Incubation Temperature." International Journal of Molecular Sciences 23, no. 12 (2022): 6608. http://dx.doi.org/10.3390/ijms23126608.
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Polyelectrolyte microcapsules (PMCs) are used in the development of new forms of drugs, coatings and diagnostic systems. Their buffer capacity, depending on the conditions of the medium, has not been practically studied, although it can affect the structure of both the capsule itself and the encapsulated agents. In this connection, we studied the buffer capacity of polyelectrolyte microcapsules of the composition (polystyrene sulfonate/polyallylamine)3 ((PSS/PAH)3) depending on the concentration and the type of salt in solution, as well as the microcapsule incubation temperature. It was found that the buffer capacity of microcapsules in the presence of mono- and di-valent salts of the same ionic strength did not differ practically. Increasing the NaCl concentration to 1 M led to an increase of buffer capacity of PMCs at pH ≥ 5, and an increase in NaCl concentration above 1 M did not change buffer capacity. The study of the buffer capacity of pre-heated PMCs showed that buffer capacity decreased with increasing incubation temperature, which was possibly due to the compaction of the PMCs and an increase in the number of compensated PAH sites. The addition of 1 M sodium chloride to heated PMCs presumably reversed the process described above, since an increase in the ionic strength of the solution led to an increase of the buffer capacity of the PMCs. The effects described above confirm the hypothesis put forward that the buffer properties of microcapsules are determined by uncompensated PAH regions in their composition.
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Leanord, Donald R., and John R. Lindsay Smith. "Model systems for cytochrome P450 dependent mono-oxygenases. Part 7. Alkene epoxidation by iodosylbenzene catalysed by ionic iron(III) tetraarylporphyrins supported on ion-exchange resins." Journal of the Chemical Society, Perkin Transactions 2, no. 11 (1990): 1917. http://dx.doi.org/10.1039/p29900001917.
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Kong, Liyun, Qiwei Yang, Huabin Xing, et al. "A general method for the separation of amphiphilic surface-active poly(ethylene glycol) mono- and di-esters with long-chain ionic liquid-based biphasic systems." Green Chem. 16, no. 1 (2014): 102–7. http://dx.doi.org/10.1039/c3gc41804a.
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Bakirova, B. S., I. A. Smagulova, and D. N. Akbayeva. "Synthesis and characterization of copper (II) chloride complexes with non-ionic polymers PEG and PVP." Chemical Journal of Kazakhstan 78, no. 2 (2022): 142–52. http://dx.doi.org/10.51580/2022-2/2710-1185.73.
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The compositions of polymer-metal complexes based on copper (II) chloride and polyethylene glycol (PEG) and polyvinylpyrrolidone (PVP) have been determined by the potentiometric method. Based on the experimental data, obtained to determine the composition of the complex, the titration curves have been plotted, and the optimal molar ratios of the reacting components have been found. The Bjerrum’s formation functions have been calculated. The obtained data indicate the formation of the polymer copper complexes, in which there are two PEG mono-links per two copper ions-complexing agent (1:2 in the Cu2+-PEG), and in the case of PVP, there are three ones (1:3 in the Cu2+-PVP). On the basis of thermodynamic constants of stability, using isotherm equations and isobars of Vant Hoff and Gibbs, Gibbs’ energy (DrG0), enthalpy (DrH0) and entropy (DrS0) changes have been calculated. The complexation process in the Cu2+-PEG and Cu2+-PEG systems is characterized by negative Gibbs’ energies, which indicates a spontaneous occurrence of the polymer-metal complex (PMC) formation process in these systems. In contrast, the complexation of copper ions with PEG is accompanied by the large positive enthalpy values, which indicate that the interaction of Cu2+ with the functional groups of the polymer is energetically unfavorable. The entropy values are positive, which can be explained by the dehydration of ions and functional groups, acting as ligands and a chelating effect during complexation, when one ion binds to several functional groups. The structure of the synthesized complexes has been investigated by IR spectroscopy.
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Fernández, Luís, Diego Montaño, Juan Ortega, and Francisco J. Toledo. "Binary Liquid–Liquid Equilibria for Systems of Mono- or Disubstituted Haloalkanes (Cl, Br) and Pyridinium-Based Ionic Liquids. Advances in the Experimentation and Interpretation of Results." Industrial & Engineering Chemistry Research 52, no. 33 (2013): 11758–66. http://dx.doi.org/10.1021/ie401710f.
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Kurihara, Makoto, Takuji Kawashima, and Kazuhiko Ozutsumi. "Complexation of Cobalt(II), Nickel(II), and Copper(II) Ions with Pyridine, 2-Methylpyridine, 3-Methylpyridine, and 4-Methylpyridine in Acetonitrile." Zeitschrift für Naturforschung B 55, no. 3-4 (2000): 277–84. http://dx.doi.org/10.1515/znb-2000-3-409.
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Abstract Thermodynamic data of the complexation of cobalt(II), nickel(II), and copper(II) ions with pyridine (py), 2-methylpyridine (2Me-py), 3-methylpyridine (3Me-py), and 4-methylpyridine (4Me-py) have been determined by calorimetry and spectrophotometry in acetonitrile (MeCN) containing 0.1 mol dm-3 (C2H5)4NClO4 as a constant ionic medium at 25 °C. The calorimetric and spectrophotometric data for py, 3Me-py, and 4Me-py revealed the formation of [ML]2+, [ML2]2+, [ML3]2+, and [ML4]2+ (M = Co2+, Ni2+, Cu2+; L = py, SMe-py, 4Me-py). For 2Me-py, on the other hand, the formation of only one complex, [M(2Me-py)]2+ (M = Co2+, Ni2+), was detected. The stepwise thermodynamic quantities and the individual electronic spectra of the complexes suggest that all of these have a six-coordinate octahedral structure. The stability of the [M(2Me-py)]2+ (M = Co2+, Ni2+) complexes is much lower than that of the corresponding py, 3Me-py, and 4Me-py complexes. The difference in the stability of the 2Me-py complexes is mainly due to their unfavorable entropy changes because the differences of enthalpies for all the complexes are not so significant. The free energies for the formation of the mono complexes follow the order Mn(II) > Co(II) > Ni(II) > Cu(II) < Zn(II) for the py, 3Me-py, and 4Me-py systems. The ΔH°1 values vary in the same order and the ΔS°1 values are similar. Hence, the stability difference of the mono complexes originates from the enthalpic term
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Kuo, Chun-Han, Ai-Yin Wang, Hao-Yu Liu, et al. "A novel garnet-type high-entropy oxide as air-stable solid electrolyte for Li-ion batteries." APL Materials 10, no. 12 (2022): 121104. http://dx.doi.org/10.1063/5.0123562.
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Li-ion batteries are considered prospective candidates for storage systems because of their high energy density and long cycling life. However, the use of organic electrolytes increases the risk of explosion and fire. Hence, all-solid-state Li-ion batteries have attracted considerable attention because the use of solid electrolytes avoids the combustion of electrolytes and explosions, and enhances the performance of batteries. Garnet-type oxides are commonly used solid electrolytes. The common Ta-doped Li7La3Zr2O12 can react easily with CO2 and H2O in air, and its ionic conductivity decays after contact with air. In this study, a novel garnet-type, high-entropy oxide, Li6.4La3Zr0.4Ta0.4Nb0.4Y0.6W0.2O12 (LLZTNYWO), is successfully synthesized as a solid electrolyte for Li-ion batteries,using a conventional solid-state method. Ta, Nb, Y, and W are used as substitutes for Zr, which significantly increase conductivity, have high stability in air, and a lower sintering temperature. LLZTNYWO achieves higher Li-ion conductivity at 1.16 × 10−4 S cm−1 compared to mono-doped Li6.6La3Zr1.6Ta0.4O12 (6.57 × 10−5 S cm−1), Li6.6La3Zr1.6Nb0.4O12 (2.19 × 10−5 S cm−1), and Li6.2La3Zr1.6W0.4O12 (1.16 × 10−4 S cm−1). Additionally, it exhibits higher ionic conductivity compared to equimolar Li5.8La3Zr0.4Ta0.4Nb0.4Y0.4W0.4O12 (1.95 × 10−5 S cm−1). The Li-ion conductivity of LLZTNYWO remains constant for 30 days in the atmosphere without decay, thereby revealing its excellent air stability. Furthermore, LLZTNYWO exhibits a remarkable electrochemical window of up to 6 V vs Li/Li+ and excellent electrochemical stability against Li metal after cycling at 0.1 mA·cm−2 for 2 h, which indicates that it is a promising solid electrolyte for Li-ion batteries.
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Delavault, André, Katarina Ochs, Olga Gorte, Christoph Syldatk, Erwann Durand, and Katrin Ochsenreither. "Microwave-Assisted One-Pot Lipid Extraction and Glycolipid Production from Oleaginous Yeast Saitozyma podzolica in Sugar Alcohol-Based Media." Molecules 26, no. 2 (2021): 470. http://dx.doi.org/10.3390/molecules26020470.
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Glycolipids are non-ionic surfactants occurring in numerous products of daily life. Due to their surface-activity, emulsifying properties, and foaming abilities, they can be applied in food, cosmetics, and pharmaceuticals. Enzymatic synthesis of glycolipids based on carbohydrates and free fatty acids or esters is often catalyzed using certain acyltransferases in reaction media of low water activity, e.g., organic solvents or notably Deep Eutectic Systems (DESs). Existing reports describing integrated processes for glycolipid production from renewables use many reaction steps, therefore this study aims at simplifying the procedure. By using microwave dielectric heating, DESs preparation was first accelerated considerably. A comparative study revealed a preparation time on average 16-fold faster than the conventional heating method in an incubator. Furthermore, lipids from robust oleaginous yeast biomass were successfully extracted up to 70% without using the pre-treatment method for cell disruption, limiting logically the energy input necessary for such process. Acidified DESs consisting of either xylitol or sorbitol and choline chloride mediated the one-pot process, allowing subsequent conversion of the lipids into mono-acylated palmitate, oleate, linoleate, and stearate sugar alcohol esters. Thus, we show strong evidence that addition of immobilized Candida antarctica Lipase B (Novozym 435®), in acidified DES mixture, enables a simplified and fast glycolipid synthesis using directly oleaginous yeast biomass.
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Kiatkittipong, Kunlanan, Muhammad Amirul Amin Mohamad Shukri, Worapon Kiatkittipong, et al. "Green Pathway in Utilizing CO2 via Cycloaddition Reaction with Epoxide—A Mini Review." Processes 8, no. 5 (2020): 548. http://dx.doi.org/10.3390/pr8050548.
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Carbon dioxide (CO2) has been anticipated as an ideal carbon building block for organic synthesis due to the noble properties of CO2, which are abundant renewable carbon feedstock, non-toxic nature, and contributing to a more sustainable use of resources. Several green and proficient routes have been established for chemical CO2 fixation. Among the prominent routes, this review epitomizes the reactions involving cycloaddition of epoxides with CO2 in producing cyclic carbonate. Cyclic carbonate has been widely used as a polar aprotic solvent, as an electrolyte in Li-ion batteries, and as precursors for various forms of chemical synthesis such as polycarbonates and polyurethanes. This review provides an overview in terms of the reaction mechanistic pathway and recent advances in the development of several classes of catalysts, including homogeneous organocatalysts (e.g., organic salt, ionic liquid, deep eutectic solvents), organometallic (e.g., mono-, bi-, and tri-metal salen complexes and non-salen complexes) and heterogeneous supported catalysts, and metal organic framework (MOF). Selection of effective catalysts for various epoxide substrates is very important in determining the cycloaddition operating condition. Under their catalytic systems, all classes of these catalysts, with regard to recent developments, can exhibit CO2 cycloaddition of terminal epoxide substrates at ambient temperatures and low CO2 pressure. Although highly desired conversion can be achieved for internal epoxide substrates, higher temperature and pressure are normally required. This includes fatty acid-derived terminal epoxides for oleochemical carbonate production. The production of fully renewable resources by employment of bio-based epoxy with biorefinery concept and potential enhancement of cycloaddition reactions are pointed out as well.
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Testa, Martin. "UN MODELLO PER L’INSEGNAMENTO DEGLI ARTICOLI ITALIANI A STUDENTI DI LINGUE MADRI SENZA ARTICOLI." Italiano LinguaDue 13, no. 2 (2022): 35–53. http://dx.doi.org/10.54103/2037-3597/17128.
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Poiché si tratta di elementi linguistici «poco salienti a livello percettivo» (Chiapedi, 2010), gli articoli rappresentano una delle aree più problematiche nell’insegnamento dell’italiano L2, specie nel caso degli apprendenti la cui madrelingua non possiede una tale categoria lessicale. Benché nel parlato una persona possa comunicare in modo più o meno efficace pur utilizzando gli articoli in modo erroneo, nella scrittura questo tipo di errori diventa particolarmente visibile in quanto la definitezza non può essere espressa che verbalmente, e quindi una debole padronanza del sistema di articoli L2 potrebbe minare il rendimento accademico degli studenti. Infatti, sul piano pedagogico, molti studiosi richiamano l’attenzione sul fatto che l’insegnamento degli articoli L2 è un compito che viene spesso trascurato oppure mal eseguito: la differenza tra definitezza e specificità viene trattata molto di rado, e ancora meno la funzione espletiva dell’articolo nei soggetti preverbali. L'obiettivo di questo contributo è quello di proporre un modello semplificato per l'insegnamento degli articoli italiani L2, sviluppato principalmente a partire dell’ipotesi della fluttuazione elaborata da Ionin, Ko, Wexler (2004), nonché sulla base della corretta interpretazione dell’articolo determinativo come operatore iota (ing. ι-operator; Chierchia, 1998) e dell’approccio euristico proposto da Testa (2021). Il modello qui proposto, dunque, si propone ridurre il numero di regole da memorizzare per gli studenti di madrelingue prive di articoli, dato che l’elevato numero di regole descritte nelle grammatiche tradizionali potrebbe sovraccaricare le risorse cognitive degli apprendenti, difficoltando così il processo di acquisizione.
 
 A model for teaching Italian articles to students of mother tongues without articles
 At the perceptual level, articles are not very salient elements (Hewson, 1972) and therefore represent one of the most problematic areas in teaching Italian L2, especially in the case of learners whose mother tongue does not possess such a lexical category. Although in speech a person can communicate more or less effectively while using articles incorrectly, in writing definiteness can only be expressed verbally and therefore a weak command of the L2 article system may undermine the academic performance of students of L2 Italian. In fact, many scholars have drawn attention to the fact that the task of teaching L2 articles is often neglected or poorly performed, e.g. the difference between definiteness and specificity is very rarely dealt with, as well as the expletive function of the article in preverbal subjects (see Longobardi, 1994). The objective of this paper is to propose a simplified model for teaching Italian L2 articles, developed based on Ionin, Ko & Wexler’s (2004) fluctuation hypothesis, the correct interpretation of the definite article as an iota operator (Chierchia, 1998) and the heuristic approach proposed by Testa (2021). Our model, therefore, aims at reducing the number of rules to be memorized by students whose L1 has no articles, given that the high number of rules described in traditional grammar textbooks may overload the cognitive resources of learners, thus hampering the learning process.
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Heubach, Maren-Kathrin, Areeg Abdelrahman, Fabian M. Schuett, Ludwig A. Kibler, and Timo Jacob. "In-Situ STM Study of Sodium Deposition Onto Au(111) in [Mppip][Tfsi]:Initial Stages, Nucleation, Cluster Growth, and Alloy Formation." ECS Meeting Abstracts MA2022-01, no. 23 (2022): 1155. http://dx.doi.org/10.1149/ma2022-01231155mtgabs.
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The development of battery systems fabricated from abundant materials that meet the highest safety requirements is a major challenge, while the demand for efficient energy storage is continuously increasing.[1] Sodium metal batteries might be an adequate substitute for lithium-ion batteries. In comparison to lithium, sodium is more abundant, is a strong reducing agent, and has a less negative standard electrode potential.[2] Investigations of the deposition and the dissolution behavior of sodium are of utmost importance since dendritic growth is amongst the key factors limiting the lifetime and safety of sodium metal batteries.[3] In-situ scanning tunneling microscopy (STM) combined with cyclic voltammetry allows observing topographical changes in real-time and to determine potential regions of related electrochemical processes. Single-crystal surfaces are commonly used in fundamental studies of metal deposition due to their (i) well-defined structure, (ii) ease and reproducibility of preparation, and (iii) stability in the electrochemical environment.[4] However, metallic sodium is extremely reactive. In particular, Na reacts violently with water and molecules containing acidic hydrogen atoms, but even with commonly used battery electrolytes as organic carbonates.[5] Fortuitously, ionic liquids (ILs) are promising solvents in sodium metal batteries.[6] Due to their unique properties, they are appropriate for preparing electrolytes in investigations of the deposition and dissolution behaviour of metals. They are known for their relatively wide electrochemical stability windows for both sodium and lithium deposition, as well as for low diffusion rates, which facilitate real-time deposition studies.[7] In this work, the initial stages of sodium underpotential deposition (UPD) onto a Au(111) electrode surface from the ionic liquid N-methyl-N-propylpiperidinium bis(trifluoromethanesulfonyl)imide ([MPPip][TFSI]) is investigated using in-situ STM and classical electrochemical measurements. Four subsequent stages in the UPD process of sodium on Au(111) can be discerned. (i) Nucleation of sodium starts around 1.1 V vs. Na/Na+ at the so-called elbows of the reconstructed Au(111) surface. (ii) Small mono-atomically high islands grow around the nuclei at a slightly more negative electrode potential of 1.0 V. (iii) The islands slowly coalesce into smooth layers after lowering the potential to 0.5 V (Figure 1), resulting in several clusters with defined steps. (iv) More islands grow on top of the existing layer and the preferred deposition mode changes from smooth layer formation to 3D-growth, resulting in cauliflower-like structures, especially at the step edges of the clusters. The deposition of several layers of sodium in the UPD regime can be explained by the alloy formation of sodium and sodiophilic gold.[8] It is worth mentioning that this deposition behaviour shows several similarities to that of lithium UPD on Au from ILs, including island formation and multiple layer growth.[7,9] So far, nucleation at the reconstruction elbows has not been reported for lithium, but it has already been observed during deposition of other metals such as nickel, cobalt, and palladium both for electrodeposition[10] and under UHV conditions.[11,12] References [1] B. L. Ellis, L. F. Nazar, Curr. Opin. Solid State Mater. Sci. 2012, 16, 168–177. [2] J. Zheng, S. Chen, W. Zhao, J. Song, M. H. Engelhard, J. Zhang, ACS Energy Lett. 2018, 3, 315–321. [3] Z. W. Seh, J. Sun, Y. Sun, Y. Cui, ACS Cent. Sci. 2015, 1, 449–455. [4] M. A. Schneeweiss, D. Kolb, Chemie unserer Zeit 2000, 34, 72–83. [5] K. Pfeifer, S. Arnold, J. Becherer, C. Das, J. Maibach, H. Ehrenberg, S. Dsoke, ChemSusChem 2019, 12, 3312–3319. [6] R. Wibowo, L. Aldous, E. I. Rogers, S. E. Ward Jones, R. G. Compton, J. Phys. Chem. C 2010, 114, 3618–3626. [7] C. A. Berger, M. U. Ceblin, T. Jacob, ChemElectroChem 2017, 4, 261–265. [8] S. Tang, Z. Qiu, X. Y. Wang, Y. Gu, X. G. Zhang, W. W. Wang, J. W. Yan, M. Sen Zheng, Q. F. Dong, B. W. Mao, Nano Energy 2018, 48, 101–106. [9] L. H. S. Gasparotto, N. Borisenko, N. Bocchi, S. Zein El Abedin, F. Endres, Phys. Chem. Chem. Phys. 2009, 11, 11140–11145. [10] M. Kleinert, H. F. Waibel, G. E. Engelmann, H. Martin, D. M. Kolb, Electrochim. Acta 2001, 46, 3129–3136. [11] D. D. Chambliss, R. J. Wilson, S. Chiang, Phys. Rev. Lett. 1991, 66, 1721–1724. [12] C. S. Casari, S. Foglio, F. Siviero, A. Li Bassi, M. Passoni, C. E. Bottani, Phys. Rev. B - Condens. Matter Mater. Phys. 2009, 79, 1–25. Figure 1
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Chirackal, Sinto, Esteban Braggio, Rahman Atiqur, et al. "Myeloma Cells Addicted to Glutamine for Biomass Production Are Sensitive to Lenalidomide." Blood 134, Supplement_1 (2019): 4410. http://dx.doi.org/10.1182/blood-2019-124967.
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Introduction We have shown that in myeloma (MM) the immunomodulatory drugs (IMiDs) lenalidomide and pomalidomide, in a CRBN dependent fashion, inhibit thioredoxin reductase and thus increase intracellular oxidative stress as a consequence of peroxide accumulation (Sebastian et al. 2017). Accordingly, we have also shown that CRBN expression alone does not fully correlate with lenalidomide sensitivity, as the cells ability to decompose H2O2 is important - MM cells with lower H2O2 decomposition capacity are more sensitive to IMiDs. We hypothezised that the specific metabolic pathways used by cells for biomass production would influence IMiD sensitivity since they also influence this cellular oxidative capacity. Cellular proteins are key elements of this biomass, and required for the proliferation of MM cells and production of immunoglobulin proteins. Methods We cultured MM cells under various nutrients conditions to understand its effect on cell proliferation and drug responses. Cell viability was assessed by MTT assay, the Luminescent Assay, and direct cell counting. MM cells glycolytic rate was measured using the Seahorse XF analyzer. Western blots were performed to quantify various protein expression levels in MM cells cultured under different nutrients conditions. CRBN CRISPR/Cas9 KO plasmid was used to generate CRBN knockout cells and a lentivirus system was used to over-express CRBN in MM cells. Results MM cells resistant to lenalidomide, but still expressing functional CRBN, show a higher glycolytic pathway use than sensitive cells. We found that the lenalidomide sensitive cell line MM1.S is highly dependent on extracellular glutamine for cell proliferation. In contrast, JJN3, a lenalidomide resistant cells line with wild type CRBN, preferentially consumes glucose. We found that glutamine depletion from culture media completely abolished lenalidomide sensitivity in MM1.S cell line. Western blot analysis revealed that antibody production by MM1.S was primarily dependent on glutamine availability, and that JJN3 antibody production was dependent upon glucose availability. While glutamine depletion from culture medium completely abolished lenalidomide sensitivity in MM1.S cell line, IKZF1, and IKZF3 degradation was unchanged. We further studied the role of CRBN in glutamine dependent cellular biomass protein production using isogenic cell lines (+/- wtCRBN). We found that wtCRBN expressing cells proliferate more and show higher antibody production in the presence of glutamine, over CRBN negative isogenic cell lines. Lenalidomide treatment further increased glutamine dependent antibody production in wtCRBN expressing cells. One possibile explanation is that activation of glutamine catabolism can facilitate protein demethylation via the supplementation α-ketoglutarate (α-KG). Therefore, we tested whether lenalidomide treatment could induce protein demethylation in sensitive cell lines. Western blot probed with mono-methyl lysine antibody showed lenalidomide induced protein demethylation. We further confirmed that protein demethylation, and lenalidomide sensitivity is a consequence of elevated α-KG by treating cells with cell-permeable 5-octyl- α-ketoglutarate which act as a substrate of the lysine demethylases. 5-Octyl-α-ketoglutarate treatment inhibited cell proliferation preferentially in wtCRBN expressing cells, and also enhanced lenalidomide induced sensitivity. Protein demethylation is associated with protein ubiquitination and proteasomal degradation. We thus hypothesize that lenalidomide induced protein demethylation also likely increases proteasome inhibitors sensitivity in MM. Conclusion MM cells with preferential glutamine consumption are likely to be more sensitive to lenalidomide, and extracellular glutamine depletion can induce lenalidomide resistance. MM cells expressing CRBN, but not dependent on glutamine for protein biomass production are more likely to be resistant to lenalidomide. Our study postulates that CRBN protein requirement in lenalidomide sensitivity cells is restricted to high glutamine dependency, and that it is quite likely CRBN has a role in glutamine metabolism. Moreover, MM cells that consume more glutamine are under higher oxidative stress and exhibit less H2O2 decomposition capacity and therefore increasing sensitivity to IMiDs. References Sebastian , S., et al., Blood 2017 129:991-1007 Disclosures Stewart: Ono: Consultancy; Roche: Consultancy; Seattle Genetics: Consultancy; Takeda: Consultancy; Amgen: Consultancy, Research Funding; Bristol Myers-Squibb: Consultancy; Celgene: Consultancy, Research Funding; Ionis: Consultancy; Janssen: Consultancy, Research Funding; Oncopeptides: Consultancy. Bergsagel:Janssen Pharmaceuticals: Consultancy; Ionis Pharmaceuticals: Consultancy; Celgene: Consultancy. Fonseca:AbbVie, Amgen, Bayer, Celgene, Kite, Janssen, Juno, Merck, Pharmacylics, Sanofi, Takeda: Other: Consultant/Advisor; Prognosticatin of MM based on Genetic Categorization by FISH: Patents & Royalties; Adaptive Biotechnologies: Other: Scientific Advisory Board.
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Tan, Liangxiao, Jun-Hao Zhou, Jian-Ke Sun, and Jiayin Yuan. "Electrostatically cooperative host-in-host of metal cluster ⊂ ionic organic cages in nanopores for enhanced catalysis." Nature Communications 13, no. 1 (2022). http://dx.doi.org/10.1038/s41467-022-29031-y.
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AbstractThe construction of hierarchically nanoporous composite for high-performance catalytic application is still challenging. In this work, a series of host-in-host ionic porous materials are crafted by encapsulating ionic organic cages into a hyper-crosslinked, oppositely charged porous poly(ionic liquid) (PoPIL) through an ion pair-directed assembly strategy. Specifically, the cationic cage (C-Cage) as the inner host can spatially accommodate a functional Au cluster, forming a [Au⊂C-Cage+]⊂PoPIL− supramolecular composite. This dual-host molecular hierarchy enables a charge-selective substrate sorting effect to the Au clusters, which amplifies their catalytic activity by at least one order of magnitude as compared to Au confined only by C-Cage as the mono-host (Au⊂C-Cage+). Moreover, we demonstrate that such dual-host porous system can advantageously immobilize electrostatically repulsive Au⊂C-Cage+ and cationic ferrocene co-catalyst (Fer+) together into the same microcompartments, and synergistically speed up the enzyme-like tandem reactions by channelling the substrate to the catalytic centers via nanoconfinement.
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Duan, Runbin, and Clifford B. Fedler. "Competitive adsorption of Cu2+, Pb2+, Cd2+, and Zn2+ onto water treatment residuals: implications for mobility in stormwater bioretention systems." Water Science and Technology, August 17, 2022. http://dx.doi.org/10.2166/wst.2022.258.
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Abstract The lack of knowledge regarding competitive adsorption of heavy metal ions onto water treatment residuals has been hindering their reuse as a media in stormwater bioretention systems. Competitive adsorption of copper(II), lead(II), cadmium(II), and zinc(II) onto polyaluminium chloride and anionic polyacrylamide water treatment residuals (PAC-APAM WTRs) was evaluated with different pH, temperature, initial concentration, and time. The competitive adsorption removal increased with the increase of pH and temperature. The analysis of the ratios of maximum adsorption capacity of a heavy metal ionic species in a multi-component system to that in a mono-component system (Qmix/Qmono) demonstrated that the coexisting ion had a negative effect on the adsorption of a metal ionic species. The Langmuir model provided a better fit indicating that the adsorption could be a monolayer adsorption process. The modified Langmuir isotherm studies showed that the affinity order in the multi-component systems was Cu2+&gt;Pb2+&gt;Cd2+&gt;Zn2+. The pseudo-second order model better described the adsorption kinetics implying that the competitive adsorption behavior could be interpreted by diffusion-based mechanisms. This study contributed to better understanding the mobility of those frequently occurring heavy metal ions in stormwater runoff in the PAC-APAM WTRs media layer of stormwater bioretention systems.
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Pei, Liang, and Li-ming Wang. "Transport Behavior of Divalent Lead Ions through Disphase Supplying Supported Liquid Membrane with PC-88A as Mobile Carrier." International Journal of Chemical Reactor Engineering 10, no. 1 (2012). http://dx.doi.org/10.1515/1542-6580.2695.
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The transport behavior of Pb(II) through a novel disphase supplying supported liquid membrane (DSSLM) with 2-ethyl hexyl phosphonic acid-mono-2-ethyl hexyl ester (PC-88A) as the carrier in kerosene, polyvinylidene fluoride membrane(PVDF) as the support and HCl as the stripping agent, has been studied. The effects of organic-to-feed volume ratio (O:F), pH, initial concentration of Pb(II) and ionic strength in the feed solution, organic-to-strip volume ratio (O:S), concentration of HCl solution and PC-88A concentration in the supplying strip phase on transport of Pb(II) have also been investigated. The advantages of DSSLM campared to the traditional SLM were investigated. The system stability, the reuse of membrane solution and the retention of membrane phase were also studied. When initial Pb(II) concentration was 2.00 × 10-4 mol/L, the transport percentage of Pb(II) was up to 92.9% under the optimun conditions in 175 min. The kinetic equation was developed in terms of the law of mass diffusion and the theory of interface chemistry. The results were in good agreement with experimental results.
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Daraie, Mansoureh, Masoud Mirzaei, Maryam Bazargan, Vadjiheh Sadat Amiri, Bita Abdolahi Sanati, and Majid M. Heravi. "Lanthanoid-containing polyoxometalate nanocatalysts in the synthesis of bioactive isatin-based compounds." Scientific Reports 12, no. 1 (2022). http://dx.doi.org/10.1038/s41598-022-16384-z.
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AbstractLanthanoid-containing polyoxometalates (Ln-POMs) have been developed as effective and robust catalysts due to their Lewis acid–base active sites including the oxygen-enriched surfaces of POM and the unique 4f. electron configuration of Ln. As an extension of our interest in Ln-POMs, a series of as-synthesized nanocatalysts K15[Ln(BW11O39)2] (Ln-B2W22, Ln = La, Ce, Nd, Sm, Gd, and Er) synthesized and fully characterized using different techniques. The Ln3+ ion with a big ionic radius was chosen as the Lewis acid center which is sandwiched by two mono-lacunary Keggin [BW11O39]9− units to form Ln-containing sandwiched type cluster. Consequently, the catalytic activity of nanocatalysts with different Ln was examined in the synthesis of bioactive isatin derivatives and compared under the same optimized reaction conditions in terms of yields of obtained products, indicating the superiority of the nano-Gd-B2W22 in the aforementioned simple one-pot reaction. The effects of different dosages of nanocatalyst, type of solvent, reaction time, and reaction temperature in this catalytic system were investigated and the best results were obtained in the presence of 10 mol% of nano-Gd-B2W22 in water for 12 min at the reflux condition.