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121.
Bolun Pang Zhijie Liu Huaiyan Zhang Sitao Wang Yuting Gao Dehui Xu Dingxin Liu Michael G. Kong 《Plasma Processes and Polymers》2022,19(1):2100079
The liquid temperature during the preparation of plasma-activated water (PAW) seriously affects the PAW chemical characteristics and its biological effect. In this study, four different temperatures (4°C, 25°C, 40°C, and 70°C) of deionized water are selected as variable parameters to investigate the effect on PAW. The results show that the physicochemical properties and the concentration of reactive oxygen and nitrogen species of PAW are significantly reduced when the temperatures are higher than 25°C; moreover, the above indexes are slightly decreased when the temperature is down to 4°C. Furthermore, by comparing the results of cell viability and apoptosis, it is found that the PAW of 25°C has a higher inactivation efficiency than other temperatures. Research on the temperature effect during PAW production is beneficial for tailoring the plasma–liquid system to enhance production efficiency. 相似文献
122.
Jérôme Sterpenich Marie-Camille Caumon Véronique Lachet Benoit Creton Mohamed El Jarmouni Aurélien Randi Pascal Robert 《Journal of Raman spectroscopy : JRS》2022,53(3):645-653
In the processes of carbon capture and storage, sulfur and nitrogen oxides (SOx and NOx) would be possibly injected with CO2 depending on the origin of CO2. The thermodynamic properties of these gases in saline aquifer are poorly known. Solubility is one of the key parameter to be implemented in geochemical codes modelling long-term evolution of the aquifer after injection. The solubility of NO is known only at atmospheric pressure. In this study, the solubility of NO in water and NaCl solutions was measured by Raman spectroscopy in the ranges 295–373 K and 2–60 MPa using a high pressure optical cell and after calibration on a few data from molecular simulations. The results show a decrease of solubility when temperature increases and when salinity increases. No modification of NO speciation was observed. 相似文献
123.
Jeanna Buldyreva Andrei Sokolov Alexander Kouzov 《Journal of Raman spectroscopy : JRS》2022,53(2):310-322
The general expression derived previously (A.P. Kouzov, J.V. Buldyreva, A.V. Sokolov, J. Chem. Phys. 149, 044305 (2018)) for the frequency-dependent rotational relaxation matrix describing collisions of linear molecules is put into an energy-corrected-sudden (ECS) form convenient for spectra modeling. The translational interaction spectral functions characterizing the intracollisional dynamics and determining the relaxation matrix elements are factorized into a frequency-dependent and an anisotropy ranks-dependent parts. The particular case of isotropic Raman Q-branch enables to establish connections of these parts with the adiabaticity factor accounting for the molecular rotation during the collision and the bimolecular relaxation rates, respectively. Analyses of these rates allow suggesting their realistic exponential-polynomial model representations with a few adjustable parameters determined from fits on experimentally available line widths. Thanks to the universal character of the non-Markovian approach, the same parameters enable realistic computations of anisotropic Raman spectra up to very far spectral wings and without any additional parameter with respect to the Markovian ECS. 相似文献
124.
在氮气环境下用PVT方法生长氮化铝过程中,氮面和铝面由于表面化学性质不同,生长的主要化学反应速度存在差异。原子在生长表面的迁移能力不同造成单晶表面生长方式差异较大。在基本相同条件下(生长温度、生长温差、生长气压、类似的籽晶、同一台生长设备)进行了铝、氮面氮化铝单晶晶体生长。为了更明显地表现铝氮面的差异,将同一片籽晶分为两半,翻转其中一半让铝氮面同时生长。铝面生长较好的区域形成了明显的晶畴,而氮面生长时生长较好的部分出现了明显的生长台阶,并出现了晶畴边界被生长台阶湮灭的生长现象,进一步通过AFM观测到铝面生长台阶平整但被缺陷所阻隔,晶畴发育明显为各晶畴独立生长。氮面生长台阶没有铝面规则但连续性较强,在原来晶畴边界位置也出现了连续的生长台阶(或台阶簇)。所以籽晶质量不高时氮面生长更容易提高晶体质量,后续的XRD测量结果也证明了氮面生长后的晶体质量明显高于铝面生长的晶体质量。 相似文献
125.
Jing Zhang Xiaoman Luo Xufang Li Prof. Qingchun Yang Prof. Jianbo He Dr. Sen Xin Dr. Xinming Yang Prof. Yan Yu Prof. Dawei Zhang Prof. Chaofeng Zhang 《ChemElectroChem》2021,8(5):949-956
The cathode catalyst for lithium-air (Li-air) batteries has a critical effect on battery performance. In this study, a two-dimensional (2D) boron and nitrogen dual-doped graphite carbon (BNC) catalyst prepared through a carbonization process was studied as a highly active electrocatalyst in Li-air batteries. BNC offered high contents of boron and nitrogen as well as a graphene-like structure. When employed as the catalyst for Li-air batteries, it demonstrated good electrochemical performance, in terms of superior discharge capacity, low voltage gap, and long-term stability. The as-prepared special structure of BNC promoted the formation and diffusion of superoxide O2− and, meanwhile, reduced the oxygen release barrier by improving the charge transfer of oxygen ions. 相似文献
126.
Rebecca Y. Hodgetts Hoang-Long Du Prof. Douglas R. MacFarlane Dr. Alexandr N. Simonov 《ChemElectroChem》2021,8(9):1596-1604
Oxidised nitrogen species (NOx) are recognised as a major source of false-positive nitrogen reduction reaction (NRR) results. Even when addressed, NOx are commonly eradicated at the initial stages of the experiment only. The present work demonstrates the shortcomings of this approach through a scrutiny of the evolution of NH3, NO2− and NO3− during the reduction of N2-saturated acetonitrile solutions with an Fe-modified electrode. Notwithstanding, thorough purification of the experimental setup, persistent evolution of NO2− during electroreduction was detected in solution and attributed to the pH increase at the electrode surface inducing the release of strongly adsorbed adventitious nitrite. This species could be then reduced to NH3, while the rate of the NRR was unmeasurably low, as confirmed by 15N2 reduction experiments. This effect of the electrochemically induced changes in pH has not been previously discussed in nonaqueous NRR, which is arguably the only effective means for the N2 electroreduction to NH3. This work also demonstrates that CH3CN might present a suitable solvent for the NRR if a genuinely active catalyst that operates at reasonable overpotentials becomes available. 相似文献
127.
Yuan Zhou Hongcheng Gao Shunlian Ning Jiaju Lin Jingbo Wen Xiongwu Kang 《ChemElectroChem》2021,8(10):1798-1806
It is still a grand challenge to achieve high performance lithium–sulfur (Li−S) batteries of high capacity, high-rate performance and long cycling performance, especially at lean electrolyte condition. Herein, a multi-functional composite interlayer is developed by in-situ polymerizing pyrrole (PPy) on graphene nanosheet (PPy/G) and examined by Fourier Transformed infrared spectroscopy, X-ray photoelectron spectroscopy and scanning electron microscopy. The graphene layers in PPy/G assure the high conductivity of the composite interlayer, while the high content of pyrrolic nitrogen sites of PPy in PPy/G composite interlayer can effectively trap the polysulfides (PSs) and promote the redox kinetics of PSs, which is valuable to suppress PSs dissolution and enhance utilization of sulfur content in Li−S batteries. Besides, the composite interlayer also facilitates the homogenous flux of Li+ and inhibits the growth of Li dendrite on Li metal anode. As a result, PPy/G interlayer delivers an impressive capacity of 535 mAh g−1 at 5 C and an area capacity of 5.18 mAh cm−2 at a sulfur load of 5.8 mg cm−2 after 100 cycles. A steady capacity of 664 mAh g−1 is also accomplished in lean-electrolyte condition after 100 cycles. 相似文献
128.
Stephan P. Blum Christean Nickel Lukas Schäffer Tarik Karakaya Prof. Dr. Siegfried R. Waldvogel 《ChemSusChem》2021,14(22):4936-4940
Aromatic nitration has tremendous importance in organic chemistry as nitroaromatic compounds serve as versatile building blocks. This study represents the electrochemical aromatic nitration with NBu4NO2, which serves a dual role as supporting electrolyte and as a safe, readily available, and easy-to-handle nitro source. Stoichiometric amounts of 1,1,1-3,3,3-hexafluoroisopropan-2-ol (HFIP) in MeCN significantly increase the yield by solvent control. The reaction mechanism is based on electrochemical oxidation of nitrite to NO2, which initiates the nitration reaction in a divided electrolysis cell with inexpensive graphite electrodes. Overall, the reaction is demonstrated for 20 examples with yields of up to 88 %. Scalability is demonstrated by a 13-fold scale-up. 相似文献
129.
130.