Journal articles: 'Spectroscopie UV-Vis'

1

Vikulov, K. A., B. N. Shelimov, and V. B. Kazansky. "IR and UV-Vis spectroscopie studies of the surface MoCH2 and MoCH-CH3 carbene complexes produced by methylcyclopropane chemisorption over photoreduced silica-molybdena catalysts." Journal of Molecular Catalysis 65, no. 3 (April 1991): 393–402. http://dx.doi.org/10.1016/0304-5102(91)85074-c.

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MASAGO, Hisashi. "UV/Vis spectroscopy." Journal of the Japan Society of Colour Material 78, no. 11 (2005): 531–38. http://dx.doi.org/10.4011/shikizai1937.78.531.

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Burgess, Chris. "UV-VIS spectroscopy." TrAC Trends in Analytical Chemistry 12, no. 7 (August 1993): x. http://dx.doi.org/10.1016/0165-9936(93)87010-u.

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De Ferri, Lavinia, Rossella Arletti, Glauco Ponterini, and Simona Quartieri. "XANES, UV-VIS and luminescence spectroscopic study of chromophores in ancient HIMT glass." European Journal of Mineralogy 23, no. 6 (December 21, 2011): 969–80. http://dx.doi.org/10.1127/0935-1221/2011/0023-2125.

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Fernandes, C. D., D. Johnson, J. C. Bridges, and Monica M. Grady. "UV-Vis spectroscopy of stardust." International Journal of Astrobiology 5, no. 4 (October 2006): 287–93. http://dx.doi.org/10.1017/s1473550406003363.

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NASA's Stardust mission flew through the coma of comet Wild 2 in January 2004, capturing dust grains as it did so. The grains were returned safely to Earth in January 2006, and are in the process of being distributed to investigators. As members of the Spectroscopy Preliminary Examination Team, we are preparing to analyse Stardust grains. Our contribution is to measure the spectrum of the grains between 200 nm (in the near ultraviolet) and 800 nm (near infrared). The purpose of the measurement is to provide an additional technique for characterizing the grains, one that is complementary to other spectroscopic techniques and one that produces results that can be matched directly with spectra acquired remotely (with telescope or spacecraft instrumentation). As part of the preparation for analysis of Stardust materials, we are producing a database of spectra from appropriate minerals, and are honing the technique through analysis of primitive meteorites.

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Sahu, Sumit Ranjan, Mayanglambam Manolata Devi, Puspal Mukherjee, Pratik Sen, and Krishanu Biswas. "Optical Property Characterization of Novel Graphene-X (X=Ag, Au and Cu) Nanoparticle Hybrids." Journal of Nanomaterials 2013 (2013): 1–9. http://dx.doi.org/10.1155/2013/232409.

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The present investigation reports new results on optical properties of graphene-metal nanocomposites. These composites were prepared by a solution-based chemical approach. Graphene has been prepared by thermal reduction of graphene oxide (GO) at 90°C by hydrazine hydrate in an ammoniacal medium. This ammoniacal solution acts as a solvent as well as a basic medium where agglomeration of graphene can be prevented. This graphene solution has further been used for functionalization with Ag, Au, and Cu nanoparticles (NPs). The samples were characterized by X-ray diffraction (XRD), Raman spectroscopy, UV-Vis spectroscopy, scanning electron microscopy (SEM), and transmission electron microscopy (TEM) to reveal the nature and type of interaction of metal nanoparticles with graphene. The results indicate distinct shift of graphene bands both in Raman and UV-Vis spectroscopies due to the presence of the metal nanoparticles. Raman spectroscopic analysis indicates blue shift of D and G bands in Raman spectra of graphene due to the presence of metal nanoparticles except for the G band of Cu-G, which undergoes red shift, reflecting the charge transfer interaction between graphene sheets and metal nanoparticles. UV-Vis spectroscopic analysis also indicates blue shift of graphene absorption peak in the hybrids. The plasmon peak position undergoes blue shift in Ag-G, whereas red shift is observed in Au-G and Cu-G.

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Zhang, Ying, Dongdong Qi, Jianzhuang Jiang, and Xuan Sun. "A novel photochromic and electrochromic europium tetraazaporphyrinato and phthalocyaninato heteroleptic double-decker for information storage." Journal of Porphyrins and Phthalocyanines 13, no. 12 (December 2009): 1197–205. http://dx.doi.org/10.1142/s1088424609001558.

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A novel tetraazaporphyrinato and phthalocyaninato mixed heteroleptic double-decker sandwich rare-earth compound with photochromic and electrochromic features has been facilely synthesized by one-pot reaction using Eu(acac)3 ·n H2O , metal-free phthalocyanine H2Pc′ ( Pc′ = 2,3,9,10,16,17,23,24-octakis(decyloxy)phthalocyanine), and the photochromic precursor 1,2-dicyano-l,2-bis(2,3,5-trimethyl-3-thienyl)ethane as starting materials. The compound was well characterized by elemental analysis and various spectroscopic methods including UV-vis, IR, 1H NMR, and mass spectroscopies. The electrochemical behavior of this compound was studied by cyclic voltammetry (CV) and differential pulse voltammetry (DPV) methods, which showed up to three one-electron oxidation and four one-electron reduction processes, demonstrating an electro-active compound for high-density information storage. The photochromic performance of the compound was detected by electronic absorption spectra, suggesting the compound to be a good candidate for non-destructive readout by means of UV-vis spectroscopy.

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TAKADA, Michinosuke. "Spectroscopic instruments. IV. UV-VIS spectrophotometer." Journal of the Spectroscopical Society of Japan 34, no. 4 (1985): 252–62. http://dx.doi.org/10.5111/bunkou.34.252.

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Grinter, R. "UV-VIS spektroskopie und ihre anwendungen (UV-VIS spectroscopy and its appplications)." Spectrochimica Acta Part A: Molecular Spectroscopy 42, no. 11 (January 1986): 1333. http://dx.doi.org/10.1016/0584-8539(86)80237-9.

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Şener, Sevil. "Ball-Type Dioxy-o-Carborane Bridged Cobaltphthalocyanine: Synthesis, Characterization and DFT Studies For Dye-Sensitized Solar Cells as Photosensitizer." Heterocyclic Communications 26, no. 1 (March 17, 2020): 37–45. http://dx.doi.org/10.1515/hc-2020-0007.

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AbstractThe synthesis and spectroscopic characterization of an innovative ball-type cobalt metallophthalocyanine 4, bridged by four 1,2-bis(2-hydroxymethyl)-O-carborane (HMOC) 1 units, has been achieved. The synthesized compound 4 was characterized structurally and electronically using elemental analysis, UV-Vis absorption spectroscopy, FT-IR spectroscopy, MALDI-TOF mass spectrometry, EPR spectroscopy and magnetic susceptibility. The photovoltaic performance of the newly synthesized compound in dye-sensitized solar cells was investigated. In order to clarify the effect of dye-sensitization time on photovoltaic performance parameters, the sensitization time was varied from 12 to 60 h and the performance parameters were investigated. It was found that sensitization time had a strong effect on the main performance parameters. The best photovoltaic performance was achieved after sensitization for 36 h (short circuit current density, 5.41 mA cm−2; overall conversion efficiency, 3.42%). Computational UV-Vis absorption spectra of the molecule was calculated using time dependent density functional theory and was found consistent with measured UV-Vis spectra.

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Görgülü, Güvenç. "Experimental and theoretical study of a novel naphthoquinone Schiff base." Open Chemistry 16, no. 1 (November 5, 2018): 1115–21. http://dx.doi.org/10.1515/chem-2018-0121.

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AbstractA novel Schiff base was synthesized and characterized by spectroscopic and theoretical methods. A potentially active agent 4-(2-hydroxy-5-methylphenylimino)naphthalen-1(4H)-one (PINQ) was designed and synthesized. The synthesis was carried out by a condensation reaction of 1-4-naphthoquinone and 2-amino-4-methyl phenol. The spectral and structural properties of the PINQ molecule were investigated by elemental analysis, 1H- and 13C-NMR, FT-IR and Uv-vis spectroscopies. The energetic, atomic, electronic, molecular, vibrational and magnetic data were theoretically obtained using density functional theory (DFT) at B3LYP level with 6-311++G(d,p) basis set. Chemical shifts were calculated using gauge-invariant atomic orbital (GIAO) method. UV-vis spectrum for the title compound was also obtained by time-dependent density functional theory (TD-DFT). The theoretical and experimental results were compared and interpreted. The theoretical data obtained from 1H- and 13C-NMR, FT-IR and Uv-vis spectroscopies were quite compatible with experimental ones.

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Tornatore, C., A. rimescu, L. Marchitto, S. S. Merola, and G. Valentino. "Combustion Process Analysis in a DISI Engine Fuelled with N-Butanol through UV-VIS Emission Spectroscopy." International Journal of Engineering and Technology 7, no. 3 (June 2015): 242–48. http://dx.doi.org/10.7763/ijet.2015.v7.799.

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13

DEY, S. C., and S. S. NATH. "SIZE-DEPENDENT PHOTOLUMINESCENCE AND ELECTROLUMINESCENCE OF COLLOIDAL CdSe QUANTUM DOTS." International Journal of Nanoscience 12, no. 02 (April 2013): 1350013. http://dx.doi.org/10.1142/s0219581x13500130.

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Here we adopt a convenient green chemical route for synthesis of CdSe quantum dots, their characterization by UV/Vis absorption spectroscopy, X-ray diffraction study and transmission electron microscopy. We carry out photoluminescence and electroluminescence spectroscopy to investigate the variation in electro-optical property with size. By UV/Vis spectroscopy, blue shift is revealed and bandgap is also calculated. X-ray diffraction spectrum reveals cubic structure and transmission electron micrographs show quantum dots of different size distributions (in the range 2–8 nm). Both the luminescence spectroscopies reveal green-orange luminescence depending upon the size distribution and indicate the possibility of using CdSe quantum dots as light emitting devices with better compatibility and faster response.

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Okretic, Stefano, and Norbert Nowack. "UV/VIS-spectroscopy of liquid slags." Steel Research 70, no. 8-9 (August 1999): 330–37. http://dx.doi.org/10.1002/srin.199905649.

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Pizarro, C., L. A. Sarabia, and J. López Palacios. "Multivariate calibration in UV-vis spectroscopy." Journal of Chemometrics 3, S1 (March 30, 2005): 241–47. http://dx.doi.org/10.1002/cem.1180030515.

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16

Al Abdel Hamid, Amer A. G., Mohammad Al-Khateeb, Ziyad A. Tahat, Mahmoud Qudah, Safwan M. Obeidat, and Abdel Monem Rawashdeh. "A Selective Chemosensor for Mercuric Ions Based on 4-Aminothiophenol-Ruthenium(II) Bis(bipyridine) Complex." International Journal of Inorganic Chemistry 2011 (May 29, 2011): 1–6. http://dx.doi.org/10.1155/2011/843051.

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A new ruthenium(II) complex (cis-ruthenium-bis[2,2′-bipyridine]-bis[4-aminothiophenol]-bis[hexafluorophosphate]) has been synthesized and characterized using standard analytical and spectroscopic techniques, FTIR, 1H and 13C-NMR, UV/vis, elemental analysis, conductivity measurements, and potentiometric titration. Investigation of the synthesized complex with metal ions showed that this complex has photochemical properties that are selective and sensitive toward the presence of mercuric ion in aqueous solution. The detection limit for mercuric ions using UV/vis spectroscopy was estimated to be ~ 0.4 ppm. The results presented herein may have an important implication in the development of a spectroscopic selective detection for mercuric ions in aqueous solution.

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DALACHE, CHERIFA, HADJ BENHEBAL, BEDHIAF BENRABAH, AEK AMMARI, ABDELMALEK KHARROUBI, and ABDELHAK LAKHAL. "CADMIUM-DOPED Co3O4 THIN FILMS: SYNTHESIS AND CHARACTERIZATION." Surface Review and Letters 26, no. 01 (January 2019): 1850134. http://dx.doi.org/10.1142/s0218625x18501342.

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This paper contains the results of the structural and spectroscopic characterizations of undoped and Cadmium-doped cobalt oxide thin films with different Co/Cd molar ratios (3%, 5%, 7% and 9%). The nanosized undoped and cadmium-doped Co3O4 thin layers were prepared using sol–gel process and deposited on glass substrates by dip coating. The changes caused by the incorporation of cadmium at different levels of doping have been highlighted by the techniques UV–Visible (UV–Vis) spectroscopy, Infrared (IR) spectroscopy, X-ray diffraction (XRD) measurements, SEM coupled EDX and impedance spectroscopy. From the UV–Vis spectroscopy analysis, it was found that all the films are two direct bandgap energies. The optical transmittance and the bandgap energy decrease with increase in Cd concentration. The XRD spectra confirm the films were polycrystalline with a cubic spinel structure. The results of the impedance spectroscopy show that the equivalent circuit of the synthesized samples is an RC parallel circuit.

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Roy, Kanak, Subhadeep Saha, Biswajit Datta, Lovely Sarkar, and Mahendra Nath Roy. "Study on Host-Guest Inclusion Complexation of a Drug in Cucurbit [6]uril." Zeitschrift für Physikalische Chemie 232, no. 2 (February 23, 2018): 281–93. http://dx.doi.org/10.1515/zpch-2017-0003.

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AbstractAssembly of pyridine-2-aldoxime drug with cucurbit [6]uril (CB[6]) has been investigated by1H-NMR and 2D-ROESY NMR, UV-Vis spectroscopy, FT-IR spectroscopy, surface tension and conductivity measurements in aqueous saline environment. The distinct cationic receptor feature and the cavity dimension of the CB[6] emphasize that the macro-cyclic host molecule remain as complex with the nerve stimulus drug molecule. The results obtained from surface tension and specific conductivity measurements suggest 1:1 inclusion complex formation between drug and CB[6]. The stability constant evaluated by UV-Vis spectroscopic approach is 2.21×105M−1at 298.15 K, which indicates that the complex is sufficiently stable at physiological temperature.

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VIJAYALAKSHMI, R., and V. RAJENDRAN. "IMPACT OF SURFACTANTS ON PHYSICAL PROPERTIES OF BaTiO3 NANOPARTICLES." International Journal of Nanoscience 12, no. 01 (February 2013): 1350003. http://dx.doi.org/10.1142/s0219581x13500038.

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Nanocrystalline BaTiO3 particles of about 20–35 nm have been successfully synthesized by using cationic, anionic and nonionic surfactants such as cetyltrimethyl ammonium bromide (CTAB), sodium dodecyl sulphate (SDS) and poly ethylene glycol (PEG) via hydrothermal method. The products were characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM), UV-Vis absorption spectroscopy and photoluminescence (PL) spectroscopy. The average particle size, measured by powder X-ray diffraction was determined to be 20–35 nm and was confirmed by transmission electron microscopy. Spherical-like morphologies were obtained by scanning electron microscopy (SEM) analysis. Optical properties of products were investigated by ultraviolet-visible (UV-Vis) absorption and PL spectroscopies.

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Helgers, Heribert, Axel Schmidt, Lara Julia Lohmann, Florian Lukas Vetter, Alex Juckers, Christoph Jensch, Mourad Mouellef, Steffen Zobel-Roos, and Jochen Strube. "Towards Autonomous Operation by Advanced Process Control—Process Analytical Technology for Continuous Biologics Antibody Manufacturing." Processes 9, no. 1 (January 18, 2021): 172. http://dx.doi.org/10.3390/pr9010172.

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Continuous manufacturing opens up new operation windows with improved product quality in contrast to documented lot deviations in batch or fed-batch operations. A more sophisticated process control strategy is needed to adjust operation parameters and keep product quality constant during long-term operations. In the present study, the applicability of a combination of spectroscopic methods was evaluated to enable Advanced Process Control (APC) in continuous manufacturing by Process Analytical Technology (PAT). In upstream processing (USP) and aqueous two-phase extraction (ATPE), Raman-, Fourier-transformed infrared (FTIR), fluorescence- and ultraviolet/visible- (UV/Vis) spectroscopy have been successfully applied for titer and purity prediction. Raman spectroscopy was the most versatile and robust method in USP, ATPE, and precipitation and is therefore recommended as primary PAT. In later process stages, the combination of UV/Vis and fluorescence spectroscopy was able to overcome difficulties in titer and purity prediction induced by overlapping side component spectra. Based on the developed spectroscopic predictions, dynamic control of unit operations was demonstrated in sophisticated simulation studies. A PAT development workflow for holistic process development was proposed.

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Stanila, Andreea, and Sorin Stanila. "Spectroscopic Studies of Aminoacids Complexes with Biometals." Chemistry Journal of Moldova 7, no. 1 (June 2012): 140–44. http://dx.doi.org/10.19261/cjm.2012.07(1).26.

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The [Cu(L)2]·H2O, [Co(L)2]·2H2O, [Zn(L)2]·H2O complexes with methionine (L) as ligand, were synthesized in water solution and analyzed by means of: elemental analysis, atomic absorption spectroscopy, thermogravimetry, FT-IR, UV-VIS and EPR spectroscopies. The atomic absorption spectroscopy and elemental measurements confi rm the ratio 1:2 metal ion: methionine composition for the synthesised compounds.The IR spectra show that amino acids act as bidentate ligands with coordination involving the carboxylic oxygen and the nitrogen atom of the amino group. Spectral UV-VIS data confi rmed the covalent metal-ligand bonds, the pseudotetrahedral symmetry around the copper and zinc ions and the octahedral environment for the cobalt ion. Powder ESR spectra at room temperature are typically for monomeric species.

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Bay, Sarah, and Thomas J. J. Müller. "Phenothiazine-Aromatic Hydrocarbon Acceptor Dyads as Photo-induced Electron Transfer Systems by Ugi Four-Component Reaction." Zeitschrift für Naturforschung B 69, no. 5 (May 1, 2014): 541–53. http://dx.doi.org/10.5560/znb.2014-4060.

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A phenothiazinyl donor moiety can be covalently coupled to aromatic hydrocarbon acceptor units via Ugi four-component reaction in an efficient, rapid, and highly convergent fashion. These novel phenothiazine-acceptor dyads are electronically decoupled in the electronic ground state according to UV/Vis spectroscopy and cyclic voltammetry. In the excited state the inherent acceptor luminescence is substantially quenched. Calculations of the Gibbs energy of photo-induced electron transfer from readily available UV/Vis spectroscopic and cyclovoltammetric data according to the Weller approximation rationalizes the feasibility of the reductive electron transfer from phenothiazine to the aromatic hydrocarbon upon photoexcitation.

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Constantinescu, Titus, Petre Ionita, Ion Chiorescu, and Gabriela Ionita. "Hydrazyl, Nitronyl-, and imino-nitroxides: Synthesis, properties and reaction with nitric oxide and nitrogen dioxide." Open Chemistry 1, no. 4 (December 1, 2003): 465–76. http://dx.doi.org/10.2478/bf02475228.

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AbstractTen novel and stable free radicals of nitronyl-, imino-nitroxide and hydrazyl type compounds were synthesized and their physico-chemical properties investigated. UV-Vis and ESR spectroscopic data, as well as the lipophilicities and specific hydrophobic areas of the compounds are compiled. The reaction of these radical compounds with nitric oxide and nitrogen dioxide was also investigated. The radicals synthesized, show selectivity in their reaction with these nitric oxides, depending on their structure (nitronyl-nitroxide radicals react with NO, while hydrazyl radicals react with NO2). The processes are easily monitored by UV-Vis or ESR spectroscopy.

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Geiger, Charles A., Andreas Stahl, and George R. Rossman. "Single-crystal IR- and UV/VIS-spectroscopic measurements on transition-metal-bearing pyrope: the incorporation of hydroxide in garnet." European Journal of Mineralogy 12, no. 2 (March 29, 2000): 259–71. http://dx.doi.org/10.1127/0935-1221/2000/0012-0259.

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25

Monakhova, Yulia B., Thomas Kuballa, Jenny Leitz, and Dirk W. Lachenmeier. "Determination of Diethyl Phthalate and Polyhexamethylene Guanidine in Surrogate Alcohol from Russia." International Journal of Analytical Chemistry 2011 (2011): 1–7. http://dx.doi.org/10.1155/2011/704795.

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Analytical methods based on spectroscopic techniques were developed and validated for the determination of diethyl phthalate (DEP) and polyhexamethylene guanidine (PHMG), which may occur in unrecorded alcohol. Analysis for PHMG was based on UV-VIS spectrophotometry after derivatization with Eosin Y and1H NMR spectroscopy of the DMSO extract. Analysis of DEP was performed with direct UV-VIS and1H NMR methods. Multivariate curve resolution and spectra computation methods were used to confirm the presence of PHMG and DEP in the investigated beverages. Of 22 analysed alcohol samples, two contained DEP or PHMG.1H NMR analysis also revealed the presence of signals of hawthorn extract in three medicinal alcohols used as surrogate alcohol. The simple and cheap UV-VIS methods can be used for rapid screening of surrogate alcohol samples for impurities, while1H NMR is recommended for specific confirmatory analysis if required.

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Mäntele, Werner, and Erhan Deniz. "UV–VIS absorption spectroscopy: Lambert-Beer reloaded." Spectrochimica Acta Part A: Molecular and Biomolecular Spectroscopy 173 (February 2017): 965–68. http://dx.doi.org/10.1016/j.saa.2016.09.037.

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BJOERNLAND, T. "ChemInform Abstract: UV-VIS Spectroscopy of Carotenoids." ChemInform 28, no. 42 (August 3, 2010): no. http://dx.doi.org/10.1002/chin.199742360.

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Garrett DeYoung, H. "UV/VIS Spectroscopy: Something Old, Something New." Nature Biotechnology 5, no. 10 (October 1987): 1088–89. http://dx.doi.org/10.1038/nbt1087-1088.

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Pospíšilová, Ľ., N. Fasurová, and V. Petrášová. " Humus content and quality under different soil tillage systems." Soil and Water Research 5, No. 3 (September 16, 2010): 90–95. http://dx.doi.org/10.17221/20/2009-swr.

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The main objective of our study was to compare the contents and quality of humic substances in selected soil types under different tillage regimes (deep, reduced, minimum). Non destructive spectroscopic methods such as UV-VIS and synchronous fluorescence spectroscopy were applied. After three years of experiments, no statistically significant differences in the total carbon content, labile carbon content, and humic substances carbon content were found. Humic substances quality and the absorbance in UV-VIS spectral range was the highest in Haplic Chernozem (minimum tillage). Fluorescence intensity varied in dependence on the soil types, however, the same main fluorophores in all samples were detected. Fluorescence of humic substances was the highest in Haplic Chernozem (minimum tillage). The determination of HS spectroscopic characteristics was found as a sensitive indicator for HS quality assessment.

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Nguyen, Tho Truong, Thi Minh Cao, Hieu Van Le, and Viet Van Pham. "Investigation of Some Characterizations of Black TiO\(_2\) Nanotubes Via Spectroscopic Methods." Communications in Physics 29, no. 2 (June 27, 2019): 189. http://dx.doi.org/10.15625/0868-3166/29/2/13762.

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The black TiO\(_2\) with substantial Ti\(^3+\) and oxygen vacancies exhibit an excellent photoelectrochemical water-splitting performance due to the improved charge transport the extended visible light response. In this study, black TiO\(_2\) nanotube arrays synthesized by the anodization method, and then, they have been investigated some characterizations by spectroscopic methods such as UV-visible reflectance (UV-vis DRS), Fourier-transform infrared spectroscopy (FTIR), Raman spectroscopy, and photoluminescence spectrum. The results showed that some highlighted properties of the black TiO2 nanotube arrays and they could apply for water-splitting effect.

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Karim, Mohammad Rezaul. "Synthesis and Characterizations of Poly(3-hexylthiophene) and Modified Carbon Nanotube Composites." Journal of Nanomaterials 2012 (2012): 1–8. http://dx.doi.org/10.1155/2012/174353.

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Poly(3-hexylthiophene) and modified (functionalized and silanized) multiwall carbon nanotube (MWNT) nanocomposites have been prepared through in situ polymerization process in chloroform medium with FeCl3oxidant at room temperature. The composites are characterized through Fourier transfer infrared spectroscopy (FT-IR), Raman, and X-ray diffraction (XRD) measurements to probe the nature of interaction between the moieties. Optical properties of the composites are measured from ultraviolet-visible (UV-Vis) and photoluminescence (PL) spectroscopy. Conductivity of the composites is followed by four probe techniques to understand the conduction mechanism. The change (if any) in C=C symmetric and antisymmetric stretching frequencies in FT-IR, the shift in G band frequencies in Raman, any alterations inλmaxof UV-Vis, and PL spectroscopic measurements are monitored with modified MWNT loading in the polymer matrix.

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Daghestani, Maha, Sarah A. Al Rashed, Wadha Bukhari, Badryah Al-Ojayan, Eiman M. Ibrahim, Asma M. Al-Qahtani, Nada M. Merghani, Rasha Ramadan, and Ramesa Shafi Bhat. "Bactericidal and cytotoxic properties of green synthesized nanosilver using Rosmarinus officinalis leaves." Green Processing and Synthesis 9, no. 1 (May 3, 2020): 230–36. http://dx.doi.org/10.1515/gps-2020-0025.

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AbstractGreen synthesized nanoparticles from plant extracts are being used in various biomedical applications, particularly because of their bactericidal and cytotoxic activities. In this study, silver nanoparticles (AgNPs) were successfully synthesized from the Rosmarinus officinalis aqueous leaf extract. Different spectroscopic and microscopic analyses such as ultraviolet-visible (UV-vis) spectroscopy, Fourier transform infrared spectroscopy (FTIR), scanning electron microscopy, and energy-dispersive X-ray spectroscopy were performed to verify the biosynthesized AgNPs in our sample. The formation of nanosilver particles was preliminarily confirmed by UV-vis spectroscopy at 400 nm. The presence of carboxylic or amide groups was confirmed by FTIR, for the reduction of the silver ion. Transmission electron microscopy confirmed a particle size of 12–22 nm. The prepared AgNPs showed good antibacterial activity against human pathogens and good cytotoxic activity against the human breast cancer cell line (MDA MB 231). The nanoparticles prepared from R. officinalis can be used for various biomedical applications.

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Diekmann, Janina, Isabell Theves, Kristoffer A. Thom, and Peter Gilch. "Tracing the Photoaddition of Pharmaceutical Psoralens to DNA." Molecules 25, no. 22 (November 10, 2020): 5242. http://dx.doi.org/10.3390/molecules25225242.

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The psoralens 8-methoxypsoralen (8-MOP), 4,5′,8-trimethylpsoralen (TMP) and 5-methoxypsoralen (5-MOP) find clinical application in PUVA (psoralen + UVA) therapy. PUVA treats skin diseases like psoriasis and atopic eczema. Psoralens target the DNA of cells. Upon photo-excitation psoralens bind to the DNA base thymine. This photo-binding was studied using steady-state UV/Vis and IR spectroscopy as well as nanosecond transient UV/Vis absorption. The experiments show that the photo-addition of 8-MOP and TMP involve the psoralen triplet state and a biradical intermediate. 5-MOP forms a structurally different photo-product. Its formation could not be traced by the present spectroscopic technique.

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Dalal, Aditya, Animesh Mandal, Shubhada Adhi, and Kiran Adhi. "Study on integration of aluminum-doped zinc oxide (AZO) thin films with graphene oxide (GO)." International Journal of Modern Physics B 32, no. 19 (July 18, 2018): 1840044. http://dx.doi.org/10.1142/s0217979218400441.

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Aluminum (0.5 at.%)-doped ZnO (AZO) thin films were deposited by pulsed laser deposition technique (PLD) in oxygen ambient of 10[Formula: see text] Torr. The deposited thin films were characterized by x-ray diffraction (XRD), photoluminescence (PL), Raman spectroscopy and uv–visible spectroscopy (UV–vis). Next, graphene oxide (GO) was synthesized by Hummers method and was characterized by XRD, UV–vis spectroscopy, Raman spectroscopy and transmission electron microscopy (TEM). Thereafter, GO solution was drop-casted on AZO thin films. These films were then characterized by Raman Spectroscopy, UV–vis spectroscopy and PL. Attempt is being made to comprehend the modifications in properties brought about by integration.

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Bremm, Dominik, and Georg Hohlneicher. "UV/VIS-Spectroscopic investigation of new porphyrin-isomers." Journal of Molecular Structure 480-481 (May 1999): 591–94. http://dx.doi.org/10.1016/s0022-2860(98)00738-8.

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36

Chang, Xiaojun, and Peter J. Vikesland. "UV–vis Spectroscopic Properties ofnC60Produced via Extended Mixing." Environmental Science & Technology 45, no. 23 (December 2011): 9967–74. http://dx.doi.org/10.1021/es201229a.

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37

Jones, D. J., R. H. French, H. Müllejans, S. Loughin, A. D. Dorneich, and P. F. Carcia. "Optical properties of AlN determined by vacuum ultraviolet spectroscopy and spectroscopic ellipsometry data." Journal of Materials Research 14, no. 11 (November 1999): 4337–44. http://dx.doi.org/10.1557/jmr.1999.0587.

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Precise and accurate knowledge of the optical properties of aluminum nitride (AlN) in the ultraviolet (UV) and visible (VIS) regions is important because of the increasing application of AlN in optical and electro-optical devices, including compact disks, phase shift lithography masks, and AlN/GaN multilayer devices. The interband optical properties in the vacuum ultraviolet (VUV) region of 6–44 eV have been investigated previously because they convey detailed information on the electronic structure and interatomic bonding of the material. In this work, we have combined spectroscopic ellipsometry with UV/VIS and VUV spectroscopy to directly determine the optical constants of AlN in this range, thereby reducing the uncertainty in the preparation of the low-energy data extrapolation essential for Kramers–Kronig analysis of VUV reflectance. We report the complex optical properties of AlN, over the range of 1.5–42 eV, showing improved agreement with theory when contrasted with earlier results.

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Nakaya, Yuki, Satoru Nakashima, and Mihoko Moriizumi. "Nondestructive Spectroscopic Tracing of Simulated Formation Processes of Humic-Like Substances Based on the Maillard Reaction." Applied Spectroscopy 72, no. 8 (May 29, 2018): 1189–98. http://dx.doi.org/10.1177/0003702818775737.

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The formation processes of humic-like substances have been simulated by heating a glycine and ribose mixed solution (0.1 mol L−1) at 80 ℃ using the Maillard reaction. Ultraviolet–visible (UV–Vis), three-dimensional excitation emission spectroscopy and size exclusion liquid chromatography succeeded in quantitatively tracing increases of the products during the heating of glycine and ribose mixed solution (0.1 mol L−1). Two-dimensional correlation spectroscopic analyses suggested that a band area around 280 nm ( UV280) and 254 nm absorbance ( UV254) can be used as measures of the formation of furfural-like intermediates and humic-like products, respectively. They were monitored using in situ UV–Vis spectroscopy with the original heatable liquid cell at 60–80 ℃. Kinetic analyses of the obtained data gave activation energies of 91.4–96.6 kJ mol−1. These nondestructive measurements by an in situ spectroscopic method did not require any additional procedures including drying or extracting the solution and they can be effectively used for direct tracing of the reaction progress and/or decomposition.

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Guo, Yuchen, Chunhong Liu, Rongke Ye, and Qingling Duan. "Advances on Water Quality Detection by UV-Vis Spectroscopy." Applied Sciences 10, no. 19 (September 30, 2020): 6874. http://dx.doi.org/10.3390/app10196874.

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Water resources are closely linked to human productivity and life. Owing to the deteriorating water resources environment, accurate and rapid determination of the main water quality parameters has become a current research hotspot. Ultraviolet-visible (UV-Vis) spectroscopy offers an effective tool for qualitative analysis and quantitative detection of contaminants in a water environment. In this review, the principle and application of UV-Vis technology in water quality detection were studied. The principle of UV-Vis spectroscopy for detecting water quality parameters and the method of modeling and analysis of spectral data were presented. Various UV-Vis technologies for water quality detection were reviewed according to the types of pollutants, such as chemical oxygen demand, heavy metal ions, nitrate nitrogen, and dissolved organic carbon. Finally, the future development of UV-Vis spectroscopy for the determination of water quality was discussed.

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Yildirim, Nuray, Neslihan Demir, Gökhan Alpaslan, Bahadir Boyacioğlu, Mustafa Yildiz, and Hüseyin Ünver. "DFT calculation, biological activity, anion sensing studies and crystal structure of (E)-4-chloro-2-((pyridin-2-ylimino)-methyl)phenol." Journal of the Serbian Chemical Society 83, no. 6 (2018): 707–21. http://dx.doi.org/10.2298/jsc171001009y.

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(E)-4-Chloro-2-[(pyridin-2-ylimino)methyl]phenol was synthesized in the reaction of 2-aminopyridine with 5-chlorosalicylaldehyde. The structure of compound was investigated by FTIR, UV?Vis, 1H-NMR, 13C-NMR and X-ray data. In addition, characterization of the compound was realized using theoretical quantum mechanical calculations and experimental spectroscopic methods. The molecular structure of the compound was confirmed using X-ray single-crystal data, NMR, FTIR and UV?Vis, which were in good agreement with the structure predicted by the theoretical calculations using the density functional theory (DFT). Moreover, the antimicrobial activity of the compound was investigated against some bacteria and yeast cultures by the broth microdilution test. UV?Vis spectroscopy studies of the interactions between the Schiff base and calf thymus DNA (CT-DNA) showed that the compound interacts with CT-DNA via electrostatic binding. The colorimetric response of the compound receptors was investigated before and after the addition of an equivalent amount of each anion to evaluate anion recognition properties.

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Jaswal, Brij Bir S., Vinay Kumar, H. C. Swart, Jitendra Sharma, Pradeep K. Rai, and Vivek K. Singh. "Multi-spectroscopic analysis of cholesterol gallstone using TOF-SIMS, FTIR and UV–Vis spectroscopy." Applied Physics B 121, no. 1 (August 15, 2015): 49–56. http://dx.doi.org/10.1007/s00340-015-6200-3.

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Rademann, K. "Photoelectron spectroscopy and UV/Vis-photoabsorption spectroscopy of isolated clusters." Zeitschrift f�r Physik D Atoms, Molecules and Clusters 19, no. 1-4 (March 1991): 161–64. http://dx.doi.org/10.1007/bf01448281.

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Moeur, Harriet P., Andrew Zanella, and Thomas Poon. "An Introduction to UV-Vis Spectroscopy Using Sunscreens." Journal of Chemical Education 83, no. 5 (May 2006): 769. http://dx.doi.org/10.1021/ed083p769.

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Felt, Deborah R., Steven L. Larson, and Edward J. Valente. "UV–VIS spectroscopy of 2,4,6-trinitrotoluene-hydroxide reaction." Chemosphere 49, no. 3 (October 2002): 287–95. http://dx.doi.org/10.1016/s0045-6535(02)00283-7.

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Antonov, Liudmil, and Stefan Stoyanov. "Noise Reduction in Second Derivative UV-Vis Spectroscopy." Spectroscopy Letters 29, no. 2 (March 1996): 231–39. http://dx.doi.org/10.1080/00387019608001599.

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Frost, L., Gerhard Geipel, K. Viehweger, and G. Bernhard. "Interaction of uranium(VI) towards glutathione – an example to study different functional groups in one molecule." Proceedings in Radiochemistry 1, no. 1 (September 1, 2011): 357–62. http://dx.doi.org/10.1524/rcpr.2011.0063.

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Abstract Glutathione, the most abundant thiol compound of the cell, has a great binding potential towards heavy metal ions. Hence it might influence the distribution of actinides on a cellular level. The unknown strength of the interaction of uranium(VI) with glutathione at physiologically relevant pH is subject of this paper and was studied with UV-vis spectroscopy and time-resolved laser-induced fluorescence spectroscopy (TRLFS). The complex stability constant of UO2H2GS+, logβ 0 121, was calculated to be 39.09 ± 0.15 and 39.04 ± 0.02 in case of UV-vis spectroscopy and TRLFS respectively. Therefore the average formation constant for UO2 2+ + H2GS− = UO2H2GS+ can be assigned to be log K 0 11 = 19.83 ± 0.15. Furthermore it was demonstrated that derivatization of the ligand associated with an enhancement of the ligand's spectroscopic properties can be used for the determination of complex stability constants and to assess the coordination chemistry in more detail. Using UV-vis spectroscopy, the stability constant of the complex between UO2 2+ and glutathione pyruvate S-conjugate, a well absorbing ligand in contrast to glutathione, was calculated to be >39.24 ± 0.08. Furthermore the interaction of UO2 2+ with glutathione derivatized with the fluorescent label monobromobimane was examined with femtosecond laser fluorescence spectroscopy. Thereby the stability constant of the 1:1 complex was determined to be >39.35 ± 0.02. Although the thiol group of glutathione was blocked a strong coordination was found. Thus a significant involvement of the thiol group in the coordination of U(VI) can be excluded.

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Simon, Lizy Roselet, and Prema Kumari J. "INCLUSION STUDIES ON α-CYCLODEXTRIN COMPLEXES OF GLIPIZIDE AND GLICLAZIDE WITH EFFECT OF PH." Asian Journal of Pharmaceutical and Clinical Research 10, no. 1 (January 1, 2016): 273. http://dx.doi.org/10.22159/ajpcr.2017.v10i1.15164.

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ABSTRACTObjective: To synthesize inclusion complexes of oral antidiabetic drugs, i.e., Glipizide (GP) and Gliclazide (Glc) with a-cyclodextrin (α-CD) and varyingthe pH which will enhance the solubility and thereby oral bioavailability of the drugs.Methods: Liquid inclusion complexes were prepared and characterized by ultraviolet-visible (UV-VIS) spectroscopic studies, and fluorescent studiessolid inclusion complexes of GP and Glc with α-CD were prepared by co-evaporation method and characterized by differential scanning calorimetricstudies (DSC) and1H nuclear magnetic resonance spectroscopic studies (1H NMR).Results: The inclusion complexes of both GP and Glc with α-CD showed high binding constant values for pH 2 from the UV-VIS spectroscopy studiesand fluorescent studies. DSC and1H NMR spectroscopic studies confirmed the inclusion of GP and Glc inside the α-CD cavity.Conclusion: Formed with more stable inclusion complexes, with α-CD are GP and Glc at pH 2, along with pH modulation could be a suitable strategyto enhance the solubility and oral bioavailability of both the drugs.Keywords: Solubility, Bioavailability, Glipizide, Gliclazide, Inclusion complexes, α-Cyclodextrin.

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Kaczmarek, Katarzyna, Andrzej Leniart, Barbara Lapinska, Slawomira Skrzypek, and Monika Lukomska-Szymanska. "Selected Spectroscopic Techniques for Surface Analysis of Dental Materials: A Narrative Review." Materials 14, no. 10 (May 17, 2021): 2624. http://dx.doi.org/10.3390/ma14102624.

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The presented work focuses on the application of spectroscopic methods, such as Infrared Spectroscopy (IR), Fourier Transform Infrared Spectroscopy (FT-IR), Raman spectroscopy, Ultraviolet and Visible Spectroscopy (UV-Vis), X-ray spectroscopy, and Mass Spectrometry (MS), which are widely employed in the investigation of the surface properties of dental materials. Examples of the research of materials used as tooth fillings, surface preparation in dental prosthetics, cavity preparation methods and fractographic studies of dental implants are also presented. The cited studies show that the above techniques can be valuable tools as they are expanding the research capabilities of materials used in dentistry.

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Eerdekens, Maarten, Ismael López-Duarte, Gunther Hennrich, and Thierry Verbiest. "Thin Films of Tolane Aggregates for Faraday Rotation: Materials and Measurement." Coatings 9, no. 10 (October 16, 2019): 669. http://dx.doi.org/10.3390/coatings9100669.

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We present organic, diamagnetic materials based on structurally simple (hetero-)tolane derivatives. They form crystalline thin-film aggregates that are suitable for Faraday rotation (FR) spectroscopy. The resulting new materials are characterized appropriately by common spectroscopic (NMR, UV-Vis), microscopy (POM), and XRD techniques. The spectroscopic studies give extremely high FR activities, thus making these materials promising candidates for future practical applications. Other than a proper explanation, we insist on the complexity of designing efficient FR materials starting from single molecules.

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Bay, Sarah, Gamall Makhloufi, Christoph Janiak, and Thomas J. J. Müller. "The Ugi four-component reaction as a concise modular synthetic tool for photo-induced electron transfer donor-anthraquinone dyads." Beilstein Journal of Organic Chemistry 10 (May 5, 2014): 1006–16. http://dx.doi.org/10.3762/bjoc.10.100.

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Phenothiazinyl and carbazolyl-donor moieties can be covalently coupled to an anthraquinone acceptor unit through an Ugi four-component reaction in a rapid, highly convergent fashion and with moderate to good yields. These novel donor–acceptor dyads are electronically decoupled in the electronic ground state according to UV–vis spectroscopy and cyclic voltammetry. However, in the excited state the inherent donor luminescence is efficiently quenched. Previously performed femtosecond spectroscopic measurements account for a rapid exergonic depopulation of the excited singlet states into a charge-separated state. Calculations of the Gibbs energy of photo-induced electron transfer from readily available UV–vis spectroscopic and cyclovoltammetric data applying the Weller approximation enables a quick evaluation of these novel donor–acceptor dyads. In addition, the X-ray structure of a phenothiazinyl–anthraquinone dyad supports short donor–acceptor distances by an intramolecular π-stacking conformation, an important assumption also implied in the calculations of the Gibbs energies according to the Weller approximation.

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Journal articles on the topic 'Spectroscopie UV-Vis'

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