Journal articles: 'Reaction range investigation'

1

Artun, Ozan. "Investigation of the production of cobalt-60 via particle accelerator." Nuclear Technology and Radiation Protection 32, no. 4 (2017): 327–33. http://dx.doi.org/10.2298/ntrp1704327a.

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The production process of cobalt-60 was simulated by a particle accelerator in the energy range of 5 to 100 MeV, particle beam current of 1 mA, and irradiation time of 1 hour to perform yield, activity of reaction, and integral yield for charged particle-induced reactions. Based on nuclear reaction processes, the obtained results in the production process of cobalt-60 were also discussed in detail to determine appropriate target material, optimum energy ranges, and suitable reactions.

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Ercan, Yildız. "Investigation of 54Fe(, n)57Ni Reaction for Low Activation Material Fe." Journal of Biomedical Research & Environmental Sciences 2, no. 9 (2021): 826–29. https://doi.org/10.37871/jbres1316.

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In fusion reactors, radioactivity can be controlled by effective material selection. Material selection is always important for effi cient conversion of radioactivity to electrical energy.The selection of structural materials provides more effi cient use of these structural materials with the results obtained from nuclear reactions. Low activation materials not only high in structural material performance and longer life, but also minimize related problems. Iron is an important element in fusion reactor technologies and astrophysical applications. For this reason, we obtained the theoretical cross-section values of the 54Fe(α, n)57Ni reaction in the range of 5-15 MeV (Mega electron volt) in this study. TALYS 1.8 (nuclear model code system) and NON-SMOKER (computer code) were used for theoretical calculations. Astrophysical S-factor values describing reactions at low energies were also calculated. In addition, reaction rate values were calculated with TALYS 1.8 and compared with EXFOR (experimental nuclear reaction data).

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Chen, Wenwu, Jianhan Liang, Lin Zhang, and Qingdi Guan. "A Numerical Investigation of Mixing Models in LES-FMDF for Compressible Reactive Flows." Energies 14, no. 16 (2021): 5180. http://dx.doi.org/10.3390/en14165180.

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The filtered mass density function (FMDF) model has been employed for large-eddy simulations (LES) of compressible high-speed turbulent mixing and reacting flows. However, the mixing model remains a pressing challenge for FMDF methods, especially for compressible reactive flows. In this work, a temporal development mixing layer with two different convective Mach numbers, Mc=0.4 and Mc=0.8, is used to investigate the mixing models. A simplified one-step reaction and a real hydrogen/air reaction are employed to study the mixing and turbulence-chemistry interaction. Two widely used mixing models, interaction by exchange with the mean (IEM) and Euclidean minimum spanning tree (EMST), are studied. Numerical results indicate that no difference is observed between the IEM and EMST models in simple reaction flows. However, for hydrogen/air reactions, the EMST model can predict the reaction more accurately in high-speed flow. For mixing models in compressible reactive flows, the requirement of localness preservation tends to be more essential as the convective Mach number increases. With the increase of compressibility, the sensitivity of the mixing model coefficient is reduced significantly. Therefore, the appropriate mixing model coefficient has a wider range. Results also indicate that a large error may result when using a fixed mixing model coefficient in compressible flows.

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Yildiz, Ercan, та Saniye Tekerek. "Investigation of 54Fe(α, n)57Ni Reaction for Low Activation Material Fe". Journal of Biomedical Research & Environmental Sciences 2, № 9 (2021): 826–29. http://dx.doi.org/10.37871/jbres1316.

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In fusion reactors, radioactivity can be controlled by effective material selection. Material selection is always important for efficient conversion of radioactivity to electrical energy.The selection of structural materials provides more efficient use of these structural materials with the results obtained from nuclear reactions. Low activation materials not only high in structural material performance and longer life, but also minimize related problems. Iron is an important element in fusion reactor technologies and astrophysical applications. For this reason, we obtained the theoretical cross-section values of the 54Fe(α, n)57Ni reaction in the range of 5-15 MeV (Mega electron volt) in this study. TALYS 1.8 (nuclear model code system) and NON-SMOKER (computer code) were used for theoretical calculations. Astrophysical S-factor values describing reactions at low energies were also calculated. In addition, reaction rate values were calculated with TALYS 1.8 and compared with EXFOR (experimental nuclear reaction data).

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Biran, Adi, Tomer Sapar, Ludmila Abezgauz, and Yaniv Edery. "Experimental investigation of the interplay between transverse mixing and pH reaction in porous media." Hydrology and Earth System Sciences 28, no. 20 (2024): 4755–70. http://dx.doi.org/10.5194/hess-28-4755-2024.

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Abstract. pH-induced reactive transport in porous environments is a critical factor in Earth sciences, influencing a range of natural and anthropogenic processes, such as mineral dissolution and precipitation, adsorption and desorption, microbial reactions, and redox transformations. These processes, pivotal to carbon capture and storage (CCS) applications to groundwater remediation, are determined by pH transport. However, the uncertainty in these macroscopic processes’ stems from pore-scale heterogeneities and the high diffusion value of the ions and protons forming the pH range. While practical for field-scale applications, traditional macroscopic models often fail to accurately predict experimental and field results in reactive systems due to their inability to capture the details of the pore-scale pH range. This study investigates the interplay between transverse mixing and pH-driven reactions in porous media. It focuses on how porous structure and flow rate affect mixing and chemical reaction dynamics. Utilizing confocal microscopy, the research visualizes fluorescently labeled fluids, revealing variations in mixing patterns from diffusive in homogeneous to shear-driven in heterogeneous media. However, pH-driven reactions show a different pattern, with a faster reaction rate, suggesting quicker pH equilibration between co-flowing fluids than predicted by transverse dispersion or diffusion. The study highlights the unique characteristics of pH change in water, which significantly influences reactive transport in porous media.

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BYSTRITSKY, V. M., V. M. GREBENYUK, S. S. PARZHITSKI, et al. "Experimental investigation of dd reaction in range of ultralow energies using Z-pinch." Laser and Particle Beams 18, no. 2 (2000): 325–33. http://dx.doi.org/10.1017/s0263034600182230.

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Experimental results on measurement of dd-reaction cross sections in the energy range of 0.1–1.5 keV using the Z-pinch technique are presented. The experiment was fulfilled at the high current generator of the High-Current Electronics Institute, city of Tomsk, Russia. The dd-fusion neutrons were registered by time-of-flight scintillator detectors and BF3 detectors of thermal neutrons. The estimates were obtained at 90% of the confidence level for the upper limits of the neutron-producing dd-reaction cross sections for average deuteron collision energies of 0.11, 0.34, 0.37, and 1.46 keV. These results substantiate feasibility to get a cross section magnitude for dd-reaction in the range of the collision energy of 0.8–3 keV using similar technology at the pulse current level of 2–3 MA.

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Yasunaga, N., S. Furukawa, Y. Kawaai, and J. Hirotsuji. "Investigation of radical reactions for efficiency improvement in ozone-hydrogen peroxide treatment." Water Science and Technology 43, no. 2 (2001): 205–12. http://dx.doi.org/10.2166/wst.2001.0091.

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It was verified by laboratory-scale experiments that the two-port ozone injection method was more advantageous for reaction efficiency in the ozone-hydrogen peroxide treatment than the conventional one-port ozone injection method under the condition of same ozone dose. The reason for this effectiveness was also investigated in detail by computer simulations in the wide range of the rate constant of OH radical reacting with TOC (kTOC). The laboratory-scale experiments revealed that the amount of TOC decomposed (δTOC) increased by up to 41% by the two-port injection method, indicating a 27% improvement in δO3/δTOC. A detailed investigation of these experimental results by computer simulations showed that by injecting ozone in two ports the amount of ozone consumed for the OH radical formation was increased more remarkably than that of ozone consumed for the radical chain reactions, and that the amount of OH radical reacting with TOC was increased more strikingly than that with ozone. Furthermore, it was found that the smaller the kTOC value within 105–109 M–1s–1 was, the more advantageous for the reaction efficiency the two-port injection method was.

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Artun, Ozan. "Investigation of production of samarium-151 and europium-152,154,155 via particle accelerator." Modern Physics Letters A 34, no. 20 (2019): 1950154. http://dx.doi.org/10.1142/s0217732319501542.

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This work aimed to investigate the production of [Formula: see text]Sm and [Formula: see text]Eu on natural Nd and Sm targets via particle accelerator because these radionuclides have the potential for use in nuclear battery technology such as betavoltaic batteries and radioisotope thermoelectric generators. Therefore, this work estimated cross-section curves for proton, deuteron, triton, helium-3, and alpha particles induced reactions in the energy range [Formula: see text]. The activities and products of yield were simulated for all reaction processes under selected conditions, the particle beam current of 1 mA and the irradiation time of 24 h. Moreover, to understand the formations of [Formula: see text] and [Formula: see text]Eu in the reaction processes, the appropriate energy region of the reactions by calculating the integral yield curves were determined. Based on the obtained results, determination of suitable targets, energy regions, and reaction processes were discussed by this work.

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Song, Jun, Jian Wang, and Li Wang. "Thermogravimetric Investigation of Calcium Oxalate." Advanced Materials Research 850-851 (December 2013): 160–63. http://dx.doi.org/10.4028/www.scientific.net/amr.850-851.160.

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The thermal properties of calcium oxalate were studied by means of TG analyzer. The factors such as heating rate, filling amounts of specimens and filling atmosphere etc., which may affect thermo gravimetric (TG) curves in TG analysis test were investigated. The results showed that, with the improving of heating rate, filling amounts of specimens and close packing, the starting reaction temperature was postponed more obviously and the width of reaction temperature range rises. The flow of the nitrogen gas enhanced heat transmission, caused the starting reaction temperature to shift to the low temperature zone, and it could also affect the response course. But the factors above didnt obviously influence the weightlessness of specimens.

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10

Tonev, R., and G. Dimova. "Investigation of chlorine wall decay in an old, decommissioned metallic pipe using a pipe section reactor." Water Supply 20, no. 3 (2020): 953–62. http://dx.doi.org/10.2166/ws.2020.017.

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Abstract The study investigates the kinetics of free chlorine depletion in tap water from the Sofia distribution network. The overall decay rates, the bulk reaction rate coefficient, the wall reaction rate coefficient and the influence of mass transfer have been determined in a laboratory pipe section reactor (PSR), testing an old decommissioned metallic pipe. In total, 23 series of experiments were performed under different initial free chlorine concentrations and different hydraulic conditions. The applicability of different chlorine decay mathematical models has been investigated. A new model was proposed, combining zero order bulk reactions and first order wall reactions, describing the laboratory results with Nash-Sutcliffe efficiency coefficients over 0.99. The obtained values for the wall reaction coefficient vary in the range 0.008–0.030 m/h, decreasing exponentially with increasing initial chlorine concentration.

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Zhao, Yuxuan, Enhua Wang, and Zhicheng Shi. "Numerical Investigation of the Ignition Delay Time of Kerosene Premixed Combustion in an SI Engine." Energies 15, no. 5 (2022): 1744. http://dx.doi.org/10.3390/en15051744.

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SI engines are installed widely in small aircrafts as they have good fuel economy. Currently, these SI engines are fueled with gasoline, although their safety can be improved if kerosene is used. However, the combustion performance of kerosene cannot fulfil the requirements due to the differences in physicochemical properties. This study investigates the ignition delay time of kerosene at a pressure range of 15–35 bar and a temperature range of 600–1000 K. A detailed chemical reaction mechanism is employed for the premixed combustion process. Under the initial conditions of 1000 K and 35 bar, with an equivalence ratio of 1, the total ignition delay time of kerosene is 0.401 ms. The NTC range of kerosene is determined as roughly 750–920 K. Subsequently, the chemical reaction paths with an equivalence ratio of 0.8, 1, and 1.2 and an initial pressure of 15, 20, and 25 bar were analyzed. The rate-determined elementary reactions were obtained based on a sensitivity analysis. The difference between kerosene and gasoline are also compared, and the rate-determining reactions that affect the ignition of kerosene and gasoline are discussed. The results of this study can provide a reference for the combustion performance improvement and knock suppression of SI engines fueled with kerosene.

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12

Puri, Prateek, Michael Mills, Christian Schneider, et al. "Synthesis of mixed hypermetallic oxide BaOCa+ from laser-cooled reagents in an atom-ion hybrid trap." Science 357, no. 6358 (2017): 1370–75. http://dx.doi.org/10.1126/science.aan4701.

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Hypermetallic alkaline earth (M) oxides of formula MOM have been studied under plasma conditions that preclude insight into their formation mechanism. We present here the application of emerging techniques in ultracold physics to the synthesis of a mixed hypermetallic oxide, BaOCa+. These methods, augmented by high-level electronic structure calculations, permit detailed investigation of the bonding and structure as well as the mechanism of its formation via the barrierless reaction of Ca (3PJ) with BaOCH3+. Further investigations of the reaction kinetics as a function of collision energy over the range 0.005 kelvin (K) to 30 K and of individual Ca fine-structure levels compare favorably with calculations based on long-range capture theory.

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13

Vlastou, R., A. Kalamara, M. Kokkoris, et al. "Investigation of (n,2n) reactions using the high energy neutron facility at NCSR “Demokritos”." HNPS Proceedings 24 (April 1, 2019): 117. http://dx.doi.org/10.12681/hnps.1853.

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In the high energy neutron facility at the 5.5MV tandem T11/25 Accelerator of NCSR "Demokritos", the neutron beam is produced by means of the 3H(d,n)4He reaction in the energy range ~15-21 MeV and at a flux of the order of 105 -106 n/cm2s. The beam has been characterized by means of the NeuSDesc and MCNP5 Monte Carlo simulations along with the multiple foil activation technique at various neutron energies. The neutron flux has been deduced using reference reactions, such as the 27Al(n,α) reaction, while the flux variation of the neutron beam was monitored by using a BF3 detector. After the characterization, the neutron beam has been used for (n,2n) reaction cross section measurements on Hf, Au and Ir isotopes via the activation technique. The irradiations were carried out at 15.3 and 17.1 MeV.

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Hwang, Seung Jun, Seung Hwan Cho, and Sukbok Chang. "Evaluation of catalytic activity of copper salts and their removal processes in the three-component coupling reactions." Pure and Applied Chemistry 80, no. 5 (2008): 873–79. http://dx.doi.org/10.1351/pac200880050873.

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The catalytic activity of a wide range of copper salts, including Cu(I) and Cu(II), has been examined in the Cu-catalyzed three-component coupling reactions of sulfonyl azides, terminal alkynes, and amines, alcohols, or water to afford N-sulfonyl amidines, imidates, and amides, respectively. Furthermore, the investigation on the ligand effect in our protocol has revealed that certain types of ligands such as tris(benzyltriazolylmethyl)amine (TBTA) exhibited notable acceleration effects on the coupling reaction. The facile and efficient methods for removing copper salts from reaction mixture were also examined.

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Han, Hong Jing, Yan Guang Chen, Hong Qi Wang, et al. "Investigation of Iodine Distribution in the Semi-Hydrate Wet Phosphoric Acid Process." Advanced Materials Research 807-809 (September 2013): 1347–50. http://dx.doi.org/10.4028/www.scientific.net/amr.807-809.1347.

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The influencing factors of reaction such as reaction temperature, reaction time and the ratio of liquid to solid are investigated by analyzing the iodine distribution in the semi-hydrate wet process of phosphoric acid. The result shows that with the increase of reaction temperature, reaction time and the ratio of liquid to solid, the iodine distribution in the phases of liquid and solid presents has the tendency of decrease, in the range between 20% and 30%, while the iodine distribution in the gas phase tends to increase, the maximum value is 67.54%.

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He, Xiangjun, Si-Ze Yang, Kun Tao, and Yudian Fan. "Investigation of the interface reactions of Ti thin films with AlN substrate." Journal of Materials Research 12, no. 3 (1997): 846–51. http://dx.doi.org/10.1557/jmr.1997.0123.

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Pure bulk AlN substrates were prepared by hot-pressing to eliminate the influence of an aid-sintering substance on the interface reactions. AlN thin films were deposited on Si(111) substrates to decrease the influence of charging on the analysis of metal/AlN interfaces with x-ray photoelectron spectroscopy (XPS). Thin films of titanium were deposited on bulk AlN substrates by e-gun evaporation and ion beam assisted deposition (IBAD) and deposited on AlN films in situ by e-gun evaporation. Solid-state reaction products and reaction mechanism of the Ti/AlN system annealed at various temperatures and under IBAD were investigated by XPS, transmission electron microscopy (TEM), x-ray diffraction (XRD), and Rutherford backscattering spectrometry (RBS). Ti reacted with AlN to form a laminated structure in the temperature range of 600 °C to 800 °C. The TiAl3 phase was formed adjacent to the AlN substrate, TiN, and Ti4N3−x as well as Ti2N were formed above the TiAl3 layer at the interface. Argon ion bombardment during Ti evaporation promoted the interface reactions. No reaction products were detected for the sample as-deposited by evaporation. However, XPS depth profile of the Ti/AlN/Si sample showed that Ti–N binding existed at the interface between the AlN thin films and the Ti thin films.

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Baibikov, M. "Investigation of the relationship between the levels of manifestation of complex sensorimotor reactions of taekwondo athletes." Scientific Journal of National Pedagogical Dragomanov University. Series 15. Scientific and pedagogical problems of physical culture (physical culture and sports), no. 6(179) (June 21, 2024): 26–33. http://dx.doi.org/10.31392/udu-nc.series15.2024.6(179).05.

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Purpose: to establish and analyze the relationship between the levels of manifestation of complex sensorimotor reactions of taekwondo players. Materials and methods. To achieve the purpose of the study, the following methods were used: analysis of scientific and methodological information and Internet sources; method of psychophysiological measurements; methods of mathematical statistics. Results: It is established, that the reaction time of a choice at highly skilled taekwondoists of the senior age is lower (better), than at taekwondoists-juniors from group 2 on 9,86% (p<0,05). Highly skilled taekwondoists have the smallest range of variation, which indicates more stable or consistent results. A higher median level and a larger range of values were observed in the group of junior taekwondoists, which indicates a greater variability of data in this group. The analysis of the average time of reaction of a choice at each stage separately showed that at highly skilled taekwondoists of the senior age this index increases on average on 88,12 ms, at taekwondoists-juniors - on 78,04 ms. The moderate inverse correlation by the criterion of Pearson between age and reaction time in group 2 (r=-0,52; p<0,05) is revealed, in group 1 such connection is not observed (r=0,07; p>0,05). The statistically significant positive relation according to Spearman's criterion between the time of choice reaction and the time of reaction to a moving object in both groups of sportsmen was established (for group 1: r=0,92; p<0,05. For group 2: r=0,50; p<0,05). It is established that the offered tests are an adequate and informative tool and can be used for monitoring of a functional condition of sportsmen in martial arts, in particular taekwon-do. Conclusions. The results of the comparative analysis of the manifestation of the choice reaction showed that highly skilled taekwondoists of the older age have it developed better than taekwondoists-juniors (p<0,05). Also the indicators of taekwondo juniors have a greater variability. The results of the analysis of interconnections between complex sensorimotor reactions confirmed that highly skilled sportsmen of older age have better developed abilities to quick and exact reaction than taekwondo juniors.

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Tóth, Akos, та Tamás Szücs. "³He(α,γ)⁷Be cross section measurement around ⁷Be known energy levels". EPJ Web of Conferences 260 (2022): 11002. http://dx.doi.org/10.1051/epjconf/202226011002.

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The 3He(α,γ)7Be reaction plays an important role in two astrophysical scenarios. It is a key reaction in lithium production during the Big Bang Nucleosynthesis and one of the central reaction in the p-p chain in stars. In the case of the former event, the Gamow energy of the reaction is around 0.2 MeV, while in the case of the p-p chain in the Sun, an order of magnitude less, around 0.023 MeV. Experimental investigation at such low energies is very difficult, if possible at all, thus low energy extrapolation inevitable to predict the reaction rate at these energies. The extrapolation and its uncertainty are inﬂuenced by the precision and covered energy range of the data used. There are many precision datasets between Ec.m. = 0.3–3.1 MeV, but only one below and one above. At higher energies known levels of 7Be exist, which motivates the study of that energy range. Therefore, we performed investigations in the energy range of Ec.m. = 4.3–8.3 MeV, where the radiative cross section has not been studied so far. For the cross section determination, the activation technique was used utilising a thin-windowed gas cell and the MGC-20 cyclotron of ATOMKI.

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Biswas, Partha. "Theoretical investigation of an atmospherically important reaction between methyl methacrylate and Cl atom: A mechanistic and kinetic approach." Journal of Theoretical and Computational Chemistry 14, no. 02 (2015): 1550010. http://dx.doi.org/10.1142/s0219633615500108.

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A theoretical investigation of the mechanism, kinetics and probable product analysis of the Cl -initiated oxidation reaction of methyl methacrylate (MMA) is presented in this paper. The major degradation pathway of MMA is the Cl -addition to the terminal carbon of the olefinic bond. Beside this, energetic and mechanism of other possible reaction pathways are discussed in detail. In addition, the mechanism for the secondary reactions in presence of O 2 and NO has also been presented. Cl -addition to the double bond takes place via formation of the pre-reactive complex as these reaction channel passes through negative activation barrier. Energetics and thermochemical analysis have been studied at the MP2=Full/6-311++g(d,p) level of theory. The rate constant of the Cl -addition reaction has been calculated using conventional transition state theory (CTST) at 1 atm pressure and 250–350 K temperature range.

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Amanuel, F. K. "Study of Reaction Mechanisms in α + 69Ga reaction at ≈10 – 50 MeV". East African Journal of Biophysical and Computational Sciences 4, № 1 (2023): 18–27. http://dx.doi.org/10.4314/eajbcs.v4i1.2s.

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The excitation functions of 69Ga(α, n)72As, 69Ga(α, 2n)71As, 69Ga(α, 3n)70As, 69Ga(α, x)69Ge, 69Ga(α, x)68Ga and 69Ga(α, x)67Ga reactions produced in the interaction of α-projectile with 69Ga-target were studied at ≈ 10-50 MeV. The produced nuclei were different isotopes of As, Ge, and Ga, some of which have important medical applications. The theoretical model predictions were based on the statistical code COMPLETE, and the predicted results were compared and discussed with existing experimental data. Good agreement between the theoretical predictions and experimental results were obtained. Pearson's relational statistics showed moderate to strong positive correlations between the theoretically predicted and experimentally measured reaction cross-sections. Furthermore, the present investigation revealed significant pre-compound contributions in the studied energy range. Therefore, it is important to consider the admixture of pre-equilibrium and equilibrium modes of reactions when predicting the reaction cross-sections.

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Lam, W. W., T. Yokota, I. Safarik, and O. P. Strausz. "Photolysis of, and the reactions of H-atoms with, isopropanethiol." Canadian Journal of Chemistry 66, no. 8 (1988): 2025–33. http://dx.doi.org/10.1139/v88-326.

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Detailed investigation of the photolysis of i-C3H7SH has been carried out in the absence and presence of the inert gas, n-C4H10. A mechanism consisting of three primary photochemical steps: [Formula: see text], [Formula: see text]; [Formula: see text], [Formula: see text]; [Formula: see text],[Formula: see text]; six hot reaction steps and seven thermal reaction steps adequately explains all the experimental observations. As in the case of hot H* atoms both the H-atom abstraction, [Formula: see text], and the SH-displacement, [Formula: see text], reactions occur with thermalized H-atoms, with the rate constant ratio k7/k8 = 19.2 ± 4.3 at 25 °C. The Arrhenius expressions have been determined over the temperature range 25–145 °C, to be: k7 = (4.0 ± 0.7) × 1012 exp [(−1066 ± 43)/RT] and k8 = (2.8 ± 0.6) × 1012 exp[(−2597 ± 114)/RT] cm3 mol−1 s−1. It was found that the overall mechanism for the photolytic decomposition of i-C3H7SH is analogous to that established for C2H5SH in previous investigations.

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MESSAOUDI, Boulanouar, Mouna CHERIET, Rayenne DJEMIL, and Djameleddine KHATMİ. "Quantum investigation of the reaction between triplet oxygen O(3P) atom and butadiene." Turkish Computational and Theoretical Chemistry 7, no. 2 (2023): 1–11. http://dx.doi.org/10.33435/tcandtc.1144794.

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We have explored the potential energy surface of the triplet oxygen atom O(3P) reaction with 1,3-butadiene at CBS-QB3 levels of theory. Possible different pathways have been determined to better understand the reaction mechanism. Thus, the first pathway of the oxidation of 1,3-butadiene by the triplet oxygen O(3P) is show that the major product is CH3-CO-CH=CH2. The results agree with those obtained experimentally in relative to the reaction enthalpies. The transition state theory (TST) was employed to compute rate constants over the temperature range 297-798K. The obtained results have shown that the electrophilic O-addition pathways on the double bond are dominant up in the temperature range. The activation energy is in line with the proposed addition mechanism.

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Aliyu, Suraj, H. I. Muhammad, and Aremu S.O. "Calculation of Nuclear Reaction Cross Section of Proton Induced Reaction of Silicon Isotopes from 1-30mev." International Journal of Research and Innovation in Applied Science IX, no. IX (2024): 186–98. http://dx.doi.org/10.51584/ijrias.2024.909017.

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Nuclear models calculation of excitation functions was performed and evaluated using the nuclear theoretical model code EXIFON. The EXIFON code, which is based on the analytical model for statistical multistep direct and statistical multistep compound reactions (SMD/SMC model), Investigation concerning the shell structure on proton induced reaction cross section of silicon isotopes ²⁸̛ ²⁹̛ ³⁰Si in the energy range of 1-30 MeV has been made. Results are benchmark and validated with data from the experimental database (EXFOR), and evaluated database (ENDF) from the International Atomic Energy Agency (IAEA) nuclear data bank. The results obtain shows that proton induced reaction has a high cross section in the interaction, which also arises from high energy protons, largely due to the large fluxes and the interaction cross section.

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Jain, Rajeev, P. Padmaja, and Seema Gupta. "Electrochemical investigation of some potential antibacterials, II." Canadian Journal of Chemistry 75, no. 5 (1997): 567–74. http://dx.doi.org/10.1139/v97-067.

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The electrochemical behaviour of 2-(4′-sulphonamoyl)hydrazonobutyrate-1,3-diones and sulphonamoylazoaminobenzenes has been studied over a wide range of pH at dropping mercury as well as glassy carbon electrodes. Both types of compounds exhibited a 4e− reduction reaction at both electrodes. At pH > 4.5, 2-(4′-sulphonamoyl)hydrazonobutyrate-1,3-diones exhibited a 2e− reduction wave at higher potentials. Both compounds undergo a 2e− oxidation reaction. On the basis of polarography, linear and cyclic voltammetry, controlled potential electrolysis, coulometry, and spectral analysis, a detailed mechanism has been postulated for the reduction as well as the oxidation. Keywords: electrochemistry, sulphonamides, polarography, cyclic voltammetry, coulometry.

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Hanna, M., and G. A. Karim. "The Combustion of Lean Mixtures of Methane and Air—A Kinetic Investigation." Journal of Energy Resources Technology 108, no. 4 (1986): 336–42. http://dx.doi.org/10.1115/1.3231286.

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The combustion of lean mixtures of methane, representing natural gas, in air is examined analytically employing a detailed chemical kinetic scheme involving 14 species and made up of 32 reaction steps that proceed simultaneously. The changes with time in the concentrations of the major relevant reactive species are determined throughout, right from the commencement of the preignition reactions to the time of achieving near equilibrium conditions. The results of such an approach to the combustion process are considered over a wide range of temperature (1200 K–2200 K) and equivalence ratios (from 0.20 to the stoichiometric value). Information is then presented in relation to some important combustion parameters that included the ignition delay, overall reaction rates and the times needed for completing the combustion process. Some guidelines are suggested for effecting eventually improved energy utilization and reduced environmental pollution from combustion processes involving lean mixtures of methane and air.

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Zhong, Ya Jie, Fan Gong Kong, Shou Juan Wang, Lei Xu, and Wen Bo Wang. "Investigation on the Electrochemical Delignification of Pulp with Syringaldehyde." Advanced Materials Research 711 (June 2013): 257–61. http://dx.doi.org/10.4028/www.scientific.net/amr.711.257.

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The low molecular syringaldehyde was found to be a preferred natural mediator for pulp delignification in the electrochemically mediated delignification system (EMD-system). Electrochemical treatment of poplar kraft pulp with syringaldehyde results in the reduction of kappa number of about 28%, but the loss of viscosity is only 6.6%. During the process of electrochemically mediated delignification , the delignification efficiency is dependent on the voltage, the dosage of syringaldehyde , reaction temperature , pH value, reaction time and the composition of electrolyte solution. The optimum operating parameters of electrochemical delignification with syringaldehyde are obtained as follows: syringaldehyde 1mmol/l, voltage 1.8v, temperature 45°C, reaction time 4.5h, the pH-value in the range from 4.0 to 5.0, sodium sulfate 0.05mol/l.

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Helmer, Magdalena, John M. C. Plane, and Matthew R. Allen. "A kinetic investigation of the reaction Ca + O3over the temperature range 213–383 K." J. Chem. Soc., Faraday Trans. 89, no. 5 (1993): 763–69. http://dx.doi.org/10.1039/ft9938900763.

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Lin, Wencheng, Bing Huang, Qiang Fu, Guowei Wang, and Junlian Huang. "Investigation of nitroxide radical coupling reaction in wide temperature range and different catalyst system." Journal of Polymer Science Part A: Polymer Chemistry 48, no. 14 (2010): 2991–99. http://dx.doi.org/10.1002/pola.24077.

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Suslikov, A. V., B. S. Zhirnov, and F. R. Murtazin. "Investigation of the Kinetic Regularities of the Interaction of Petroleum Coke with Phosphogypsum to Calcium Sulfide." Chemistry and Technology of Fuels and Oils 625, no. 3 (2021): 32–35. http://dx.doi.org/10.32935/0023-1169-2021-625-3-32-35.

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This study describes the research results of petroleum coke (carbon) and phosphogypsum reaction and the methods used for the above. Stoichiometric petroleum coke and phosphogypsum mixtures were prepared for the study. The coke was cut and screened with particle size distribution of 0.25-0.315 mm and dried at 110 °С temperature. The phosphogypsum sample was also cut and screened with the same particle size and was pre-heated within the 100-200 °С range up to permanent mass. The weighed samples were heated within 900 till 1000 °С, the range being typical to one of reaction stages between coke and phosphogypsum, i.e. the decomposition reaction with the products of calcium sulfide and carbon dioxide. The extend and rate of samples conversion and their time correlations were obtained for the number of reaction temperatures. Reaction rate constant and activating energy were calculated based on this correlations results.

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Bhattacharya, S., J. D. Belgrave, D. G. Mallory, R. G. Moore, M. G. Ursenbach, and S. A. Mehta. "Investigation of Thermal Fingerprint in Accelerating-Rate Calorimetry for Air-Injection Enhanced-Oil-Recovery Processes." SPE Journal 22, no. 02 (2016): 548–61. http://dx.doi.org/10.2118/178095-pa.

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Summary The accelerating-rate calorimeter (ARC) is unique for its exceptional adiabaticity, its sensitivity, and its sample universality. Accelerating Rate Calorimetry is one of the screening tests used to determine the suitability for air-injection enhanced oil recovery (EOR). These tests show oil reactivity and exothermicity over a broad range of temperatures: low-temperature range (LTR), negative-temperature-gradient region (NTGR), and high-temperature range (HTR). An experimental and simulation study was carried out to expand understanding and interpretation of the data derived from high-pressure closed-ARC tests. Athabasca bitumen was used for the experimental study in a closed ARC at 13.89 MPag (2000 psig) to identify the temperature ranges over which the oil reacts with oxygen in the injected air. Self-heat rate from accelerating-rate calorimetry and mass-loss rates from the differential thermogravimetric analysis show the influence of mass transfer of oxygen within bitumen in the LTR and HTR. A numerical model was developed to integrate the concept of mass transfer with a reaction-kinetic model. The model incorporates solubility of oxygen with partition equilibrium coefficient (K-value) as a medium to introduce oxygen into the bitumen layer, which later transfers throughout oil layer by diffusion. This model considers both low- and high-temperature oxidation (LTO and HTO), and thermal-cracking reactions, as described in traditional reaction-kinetic models of in-situ-combustion (ISC) processes. Results show that formation of an asphaltenes film in the LTR caused by oxidation of maltenes obstructs oxygen (mass-transfer restriction) penetration into the bitumen layer. The simulated result shows that, by integrating mass transfer with the kinetic model, it is possible to predict the NTGR. Viscosity and temperature dependence on the mass transfer of oxygen is linear. As time passes and chemical reaction becomes more important with increasing temperature, the relationship deviates from linearity. With increasing temperature, the influence of chemical interaction on the oxygen distribution becomes greater, and this results in a shorter initial stage of mass transfer of oxygen within the bitumen film at low temperatures. This implies that the ARC can be a useful tool for understanding the effect of mass transfer on the oxidation characteristic for predicting LTR, NTGR, and HTR.

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Doppiu, Stefania, Jean-Luc Dauvergne, and Elena Palomo del Barrio. "Solid-State Reactions for the Storage of Thermal Energy." Nanomaterials 9, no. 2 (2019): 226. http://dx.doi.org/10.3390/nano9020226.

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In this paper, the use of solid-state reactions for the storing of thermal energy at high temperature is proposed. The candidate reactions are eutectoid- and peritectoid-type transitions where all the components (reactants and reaction products) are in the solid state. To the best of our knowledge, these classes of reactions have not been considered so far for application in thermal energy storage. This study includes the theoretical investigation, based on the Calphad method, of binary metals and salts systems that allowed to determine the thermodynamic properties of interest such as the enthalpy, the free energy, the temperature of transition, the volume expansion and the heat capacity, giving guidelines for the selection of the most promising materials in view of their use for thermal energy storage applications. The theoretical investigation carried out allowed the selection of several promising candidates, in a wide range of temperatures (300–800 °C). Moreover, the preliminary experimental study and results of the binary Mn-Ni metallic system are reported. This system showed a complex reacting behavior with several discrepancies between the theoretical phase diagram and the experimental results regarding the type of reaction, the transition temperatures and enthalpies and the final products. The discrepancies observed could be due both to the synthesis method applied and to the high sensitivity of the material leading to partial or total oxidation upon heating even if in presence of small amount of oxygen (at the ppm level).

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Zhelyazkova, Valentina, Fernanda B. V. Martins, Matija Žeško, and Frédéric Merkt. "Multipole-moment effects in ion–molecule reactions at low temperatures: part II – charge–quadrupole-interaction-induced suppression of the He⁺ + N₂ reaction at collision energies below k_B·10 K." Physical Chemistry Chemical Physics 24, no. 5 (2022): 2843–58. http://dx.doi.org/10.1039/d1cp04798a.

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33

Sazou, Dimitra, and Ioannis Poulios. "Electrochemical behaviour of 2,5-dihydroxyanisole on a mercury electrode in aqueous media." Collection of Czechoslovak Chemical Communications 54, no. 1 (1989): 42–52. http://dx.doi.org/10.1135/cccc19890042.

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Electrochemical investigation of 2,5-dihydroxyanisole (2,5-DHA) has been carried out in aqueous solutions in pH range 2-11 on hanging mercury drop electrode (HMDE). The oxidation process in pH range 2-6 is a quasi-reversible electrode reaction which involves the transfer of two electrons and two protons. By use of semi-integration a dependence of the heterogeneous rate constant on the potential has been appreciated. Thus, the variation of peak current with pH changes can be explained. In more basic solutions the electrooxidation is complicated by subsequent chemical reactions as indicated from the calculated voltammetric and chronoamperometric parameters.

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Jones, Frank, Idongesit Bassey Anweting, Idongesit Edem Okon, and Kenneth Edet Andem. "Spectrophotometric Study of Kinetics of Redox Reaction between Caffeine and Permanganate Ion in Aqueous Acidic Medium." Asian Journal of Chemical Sciences 13, no. 3 (2023): 1–9. http://dx.doi.org/10.9734/ajocs/2023/v13i3239.

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The kinetics of redox reaction between caffeine (hereafter referred to as CAF) and permanganate ion [MnO4-] has been studied spectrophotometrically in aqueous sulfuric acid medium. One mole of CAF was oxidized by one mole of [MnO4-].The reaction showed first-order kinetics with respect to both [CAF] and [MnO4-]. The investigation was carried out under pseudo-first order condition atI= 0.5 mol dm–3, (Na2SO4), T = 24± 0.1℃ and [H+] = 1.0 × 10–1mol dm-3. The reaction obeys the rate law: -d[MnO4-]/dt = (a+b [H+]) [CAF ] [MnO4-]. The reaction was retarded by increased in ionic strength of the reaction medium. The rate of the reaction showed dependence on acid (in the range used).Added anions and cations were observed to catalyze the reaction rate. Spectroscopic investigation and kinetic study did not suggest intermediate complex formation. An outer–sphere mechanism is proposed for the reaction.

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Ryan, Sarah J., Christopher D. Thompson, and David W. Lupton. "A Synthetic and Computational Investigation into the Direct Synthesis of ?-Hydroxymethylated Enones from ?-Keto Phosphonates." Australian Journal of Chemistry 62, no. 7 (2009): 720. http://dx.doi.org/10.1071/ch09301.

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The synthesis of a range of α-hydroxymethylated enones has been achieved using the Villiéras modification of the Horner–Wadsworth–Emmons (HWE) reaction. Scope, limitations, and mechanistic aspects of this reaction were investigated using a combination of synthetic and computational studies. These investigations support a Schlosser–Corey type reaction mechanism that is balanced between two pathways with the outcome influenced by the steric environment of the substrate.

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Ji, G. D., X. R. Zhang, and F. Guo. "Investigation of carbazole degradation by the sono-Fenton process." Water Science and Technology 68, no. 3 (2013): 608–13. http://dx.doi.org/10.2166/wst.2013.245.

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The present report aimed to describe the roles of ultrasonic power and reaction time in the Fenton reagent-based degradation of carbazole in wastewater, and to analyze the effects of the Fe2SO4 and H2O2 concentrations and the initial pH on the reaction kinetics. Application of 40 or 80 W of ultrasound at a frequency of 40 KHz substantially improved the effectiveness of carbazole degradation, whereas application of 20 W of ultrasound had little effect. The optimal concentration of the Fe2SO4·7H2O catalyst was lower for extended operating times. Increased degradation was observed with increasing H2O2 concentrations below 1.8 mg L−1, whereas decreased degradation was observed at concentrations above this value. The best performance was obtained at a neutral or slightly alkaline pH range (pH 7–9) rather than at the commonly used acidic pH range (pH 2–4). Under optimal conditions, the extent of carbazole degradation was 98% after 180 min. The degradation process followed second-order kinetics.

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Conti, Fosca, Alexander Hanss, Carolin Fischer, and Gordon Elger. "Thermogravimetric investigation on the interaction of formic acid with solder joint materials." New Journal of Chemistry 40, no. 12 (2016): 10482–87. http://dx.doi.org/10.1039/c6nj02396g.

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Stengler, Jana, Julius Weiss, and Marc Linder. "Analysis of a Lab-Scale Heat Transformation Demonstrator Based on a Gas–Solid Reaction." Energies 12, no. 12 (2019): 2234. http://dx.doi.org/10.3390/en12122234.

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Heat transformation based on reversible chemical reactions has gained significant interest due to the high achievable output temperatures. This specific type of chemical heat pump uses a reversible gas–solid reaction, with the back and forward reactions taking place at different temperatures: by running the exothermic discharge reaction at a higher temperature than the endothermic charge reaction, the released heat is thermally upgraded. In this work, we report on the experimental investigation of the hydration reaction of strontium bromide (SrBr2) with regard to its use for heat transformation in the temperature range from 180 °C to 250 °C on a 1 kg scale. The reaction temperature is set by adjusting the pressure of the gaseous reactant. In previous experimental studies, we found the macroscopic and microscopic properties of the solid bulk phase to be subject to considerable changes due to the chemical reaction-. In order to better understand how this affects the thermal discharge performance of a thermochemical reactor, we combine our experimental work with a modelling approach. From the results of the presented studies, we derive design rules and operating parameters for a thermochemical storage module based on SrBr2.

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Pezzatini, Giovanni, Francesca Loglio, Massimo Innocenti, and Maria Luisa Foresti. "Selenium(IV) Electrochemistry on Silver: A Combined Electrochemical Quartz-Crystal Microbalance and Cyclic Voltammetric Investigation." Collection of Czechoslovak Chemical Communications 68, no. 9 (2003): 1579–95. http://dx.doi.org/10.1135/cccc20031579.

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The electrochemical behavior of Se(IV) on silver was investigated by cyclic voltammetry and electrochemical quartz-crystal microbalance (EQCM) measurements. As already reported in the literature, Se(IV) electrochemistry is always complex, and on silver even more, due to the formation of a compound. Our results confirm that the reduction process of Se(IV) occurs through two reaction paths, Se(IV) → Se(0) and Se(IV) → Se(-II); the product Se(-II) then reacts with Se(IV) through a comproportionation reaction. The latter step leads to red Se that, according to the literature, is the only electroactive form of Se(0). The presence of the electroactive red Se is evident both in the negative range of potentials, through the reduction Se(0) → Se(-II), and in the less negative range of potentials, through the oxidation Se(0) → Se(IV). Moreover, our measurements pointed to the formation of a deposit that never redissolves. This deposit seems to be the electroinactive gray Se. The electrochemical behavior of Se(IV) was investigated in the whole potential range accessible on silver. Our results confirm the occurrence of competitive processes whose predominance depends on the scan rate, as well as on the potential limits of voltammetry. A detailed table with the processes occurring in different potential ranges was drawn up.

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Vlastou, R., M. Anastasiou, A. Kalamara, et al. "High-energy neutron facility at the Athens Tandem Accelerator NCSR “Demokritos”." HNPS Proceedings 21 (March 8, 2019): 123. http://dx.doi.org/10.12681/hnps.2015.

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In the 5.5 MV tandem T11/25 Accelerator Laboratory of NCSR “Demokritos” monoenergetic neutron beams have been produced in the energy range ∼16–19 MeV using a new Ti-tritiated target of 373 GBq activity, by means of the 3H(d,n)4He reaction. The corresponding beam energies obtained from the accel- erator, were 0.8–3.7 deuterons. The maximum flux has been determined to be of the order of 106 n/s·cm2, implementing reference reactions. An investigation of the energy dependence of the neutron fluence has been carried out with the multiple foil activation technique. The beam has been used for the measurement of (n,2n) reaction cross section on several isotopes at 16.7 and 17 MeV.

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Zinabe Kebede, Baye. "Investigation of α-induced Reaction on Copper Isotopes for Energy Range of 15-50 Mev". Nuclear Science 6, № 2 (2021): 12. http://dx.doi.org/10.11648/j.ns.20210602.12.

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42

Blomqvist, K. I., W. U. Boeglin, R. Böhm та ін. "Investigation of short-range nucleon-nucleon correlations using the reaction in close to 4π geometry". Physics Letters B 421, № 1-4 (1998): 71–78. http://dx.doi.org/10.1016/s0370-2693(98)00024-0.

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43

Swinnen, Saartje, Rehab M. I. Elsamra, Vinh Son Nguyen, Jozef Peeters, Shaun A. Carl, and Minh Tho Nguyen. "Theoretical and experimental investigation of the C2H+SO2 reaction over the range T=295–800K." Chemical Physics Letters 513, no. 4-6 (2011): 201–7. http://dx.doi.org/10.1016/j.cplett.2011.07.098.

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44

Kojčinović, Aleksa, Blaž Likozar, and Miha Grilc. "Mechanism, Kinetics and Modelling of Phenol Carboxylation Reactions with CO2." International Journal of Molecular Sciences 25, no. 23 (2024): 12923. https://doi.org/10.3390/ijms252312923.

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Combining carboxylation reactions using carbon dioxide (CO2) as a reactant with phenol results in creation of new C-C bonds, and represents one of the most promising routes in sustainable utilization of ubiquitous and readily available resources for production of highly valuable products. This study provides a detailed and well-structured investigation of the effect of various reaction conditions (reactant loading, reaction duration, temperature, CO2 pressure) on the carboxylation of phenol. Sodium phenoxide carboxylation showed well-resolved trends with variation of temperature and time, and resulted in production of salicylic acid (SA) in the range of 11.4 to 47.8%, 4-hydoxybenzoic acid (4HBA) in the range of 2.0 to 8.2%, while the dicarboxylated 4-hydroxyisophthalic acid (4HiPh) was only detected in trace amounts. The effect of the variation of reactant content was shown to be significantly influenced by the reactor size, solid/vessel and gas/solid contact area, as well as the efficiency of the stirring. CO2 pressure was shown to be a crucial element, where reactions carried out below 2 MPa CO2 did not show any activity. While investigating the reaction mechanism, it was shown that the salt analogues of potential products could be acidified in situ by the moisture present, and immediately degraded back to phenol, thus lowering yields of potentially obtained products. The experimental results were successfully used to compose a kinetic model, which very well describes the experimentally obtained results. As such, this study provides a valuable dataset for valorization of lignocellulosic aromatic compounds as well as highly abundant and environmentally detrimental carbon dioxide into industrially valuable mono- and dicarboxylic acids.

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M, Heravi; Majid, S. Sadjadi, M. Malmir, and F. Noritajer. "Copper incorporated into 1H-1,2,3-triazole-5-methanol functionalized halloysite nano clay as an efficient and heterogeneous catalyst for promoting green A3 and KA2 coupling reaction: Optimization of reaction variables using response surface methodology." Materials Chemistry and Physics 223 (February 1, 2019): 380–90. https://doi.org/10.1016/j.matchemphys.2018.10.057.

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Design and synthesis of a novel heterogeneous catalyst based on functionalization of halloysite nanoclay with 1H-1,2,3-triazole-5-methanol and subsequent incorporation of copper is disclosed. The obtained catalyst was fully characterized by employing ICP-AES, SEM/EDX, TGA, XRD, BET and FTIR and successfully used for promoting the A3 and KA2 coupling reactions of phenylacetylene, amines and aldehydes or ketone in aqueous media. The reaction variables including reaction temperature and amount of the catalyst were optimized using Response Surface Methodology (RSM). The catalyst exhibited excellent catalytic activity under optimum reaction condition. Notably, the investigation of the reusability of the catalyst confirmed that the catalyst could be recovered and reused up to four reaction runs with only slight loss of the catalytic activity. The hot filtration experiment also demonstrated low leaching of copper species, indicating the heterogeneous nature of the catalysis. Easy work-up procedures, performing the reaction in aqueous media, broad range of substrate scope and low reaction times are other merits of this protocol.

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46

Wang, Hui, Armin Monir, and Xinjun (Eric) Wu. "Application of corrosion-resistant Corning advanced-flow reactors for multiphase Bunsen reaction - Part two: investigation on multiphase reaction." International Journal of Petrochemical Science & Engineering 4, no. 4 (2019): 154–60. http://dx.doi.org/10.15406/ipcse.2019.04.00115.

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Bunsen reaction ( 2 H 2 O + I 2 + S O 2 → H 2 S O 4 + 2 H I ) is a key step for hydrogen production from either the H2S splitting cycle or the sulfur-iodine (S-I) cycle of water splitting. As pointed out in part one, when engineering this reaction, many challenges such as side reactions and corrosion impede scaling up this process. Using iodine-toluene solution to provide flowing iodine below the melting point of iodine renders the Bunsen reaction to be conducted at ambient temperature such that these challenges can be either overcome or eased. However, using toluene as the iodine solvent makes the Bunsen reaction a multiphase reaction system which includes gas, aqueous, and organic phases. Glass-made Corning® advanced-flowTM reactors (AFRs) can be used for Bunsen reaction because they are good at resisting corrosion, improving mixing efficiency of multiphase fluids, and allowing seamless scaling up. Part one has studied the absorption behavior of SO2 gas in the liquids used for Bunsen reaction (water, toluene and water-toluene mixture). Part two (this work) mainly studies the Bunsen reaction using the Corning® microscale (LF) and milliscale (G1) AFRs. When I2 was dissolved in toluene, the Bunsen reaction was conducted by feeding SO2 gas, water, and I2/toluene solution into the AFRs. SO2 and I2 were used as the limiting reactants in turn, and the effects of operating conditions such as gas and liquid flow rates, water to toluene ratio, and temperature in the range (22-80 oC) on the absorption rates of SO2 and the I2 reaction rate were studied. The results confirm the seamless scaling-up capability of the Corning reactors when the flow rates were increased twenty times from AFR-LF to AFR-G1.

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47

Wolf, Stephanie E., Lucy Dittrich, Markus Nohl, et al. "Boundary Investigation of High-Temperature Co-Electrolysis Towards Direct CO₂ Electrolysis." Journal of The Electrochemical Society 169, no. 3 (2022): 034531. http://dx.doi.org/10.1149/1945-7111/ac5e45.

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In the temperature range of high temperature co-electrolysis of both steam and carbon dioxide, the reverse water-gas shift reaction (RWGS) takes place. Prior studies were conducted with a narrow gas composition range to investigate the role of RWGS during co-electrolysis. The results for steam electrolysis, CO2 electrolysis, and co-electrolysis caused different conclusions regarding the role of electrochemical CO2 and H2O conversion compared to RWGS during co-electrolysis. This work aims to resolve the role of CO2 conversion as part of RWGS in co-electrolysis. The boundary is characterized by AC and DC measurements over a broad gas composition range from CO2 electrolysis towards co-electrolysis with nearly 50%eq H2O. Especially, the electrochemical CO2 reduction and CO2 conversion in the RWGS are compared to clarify their role during co-electrolysis. The results revealed that gas composition determined the predominant reaction (H2O or CO2 reduction). The cell performance of co-electrolysis in the boundary region up to 5%eq H2O was similar to the performance of CO2 electrolysis. Up to 30%eq H2O, the performance increases with H2O concentration. Here, both CO2 and H2O electrolysis occur. Above 30%eq H2O, steam electrolysis and the RWGS reaction both dominate the co-electrolysis process.

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Sueishi, Yoshimi, та Shotaro Itami. "Investigation of the Pressure Effects on Inclusion Equilibria of Substituted Phenols with β- and γ-Cyclodextrins". Zeitschrift für Physikalische Chemie 217, № 6 (2003): 677–88. http://dx.doi.org/10.1524/zpch.217.6.677.20440.

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AbstractThe effects of pressure were examined for the inclusion complexation of β- and γ-cyclodextrins (CDs) with 4-substituted phenols. The reaction volume for the CD inclusion complexation with 4-substituted phenols, which is the change in volume accompanied by CD inclusion, was estimated from the pressure dependence of the inclusion equilibria. The reaction volumes estimated for the phenols/β-CD system were positive values in the range of 2.5 and 14.0cm3mol−1, while those for the phenols/γ-CD system were negative in the range of −11.8 and −0.8cm3mol−1. The difference in the reaction volumes for the inclusion complexation of β- and γ-CDs is explained in terms of the difference in the number of water molecules repelled from the CD cavity. Based on the results, the inclusion behavior of CD complexation is discussed.

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M., Kavitha, Shenbagam K., Balasubramaniyan M., Sridharan R., and Mathiyalagan N. "Kinetics and mechanistic investigation of N-bromonicotinamide oxidation of aromatic aldehydes." Journal of Indian Chemical Society Vol. 86, Oct 2009 (2009): 1108–11. https://doi.org/10.5281/zenodo.5820595.

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P.G. and Research Department of Chemistry, St. Joseph's College (Autonomous), Thiruchirappalli-620 002, Tamilnadu, India E-mail: sjcmathi@yahoo.co.uk, kavi_19475@yahoo.co.in Manuscript received 27 May 2009, accepted 10 June 2009 N-Bromonicotinamide (NBN) oxidation of aromatic aldehydes is investigated in aqueous acetic acid and perchloric acid medium over the temperature range of 313-328 K. The reaction exhibits first order dependence on [NBN] and the zero order dependence on [substrate]. The fractional order dependence of rate on [H+] suggests complex formation between NBN and H+. The reaction fails to induce polymerization of acrylonitrile under the experimental conditions employed. Arrhenius and activation parameters are evaluated. Effects of dielectric constant and ionic strength of the medium on the reaction rate have been studied. Oxidation products are identified. A most probable reaction mechanism is proposed and an appropriate rate law is deduced to account for the observed kinetic data.

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MUATAZ, A. A., F. AHMADUN, C. GUAN, E. MAHDI, and A. RINALDI. "EFFECT OF REACTION TEMPERATURE ON THE PRODUCTION OF CARBON NANOTUBES." Nano 01, no. 03 (2006): 251–57. http://dx.doi.org/10.1142/s1793292006000288.

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A floating catalyst chemical vapor deposition (FC-CVD) method was designed and fabricated to produce high quality and quantity carbon nanotubes. The reaction temperature was optimized to produce high yield and purity of the carbon nanotubes. The reaction temperatures were varied from 500–850°C. The result shows that carbon nanotubes were observed from 600°C to 850°C with maximum numbers and high purity at 850°C. The diameter range of CNTs varied from 2 to 55 nm. The results of the present investigation suggest that the observed changes in catalytic activity and selectivity accompanying an increase in temperature are probably due to major alterations in the distribution of atoms at the metal/gas interface. Thermodynamically, higher temperatures favor the surface decomposition of hydrocarbon rather than the hydrogenation reactions.

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Journal articles on the topic 'Reaction range investigation'

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