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991.
992.
A density functional and ab initio theory investigation on M@B9 and M@B10 molecular wheels containing planar nona- and deca-coordinate heavy group 11, 12 and 13 metals (M=Ag, Au, Cd, Hg, In, Ti)
has been performed. These unusual clusters all prove to be true minima on the potential energy surfaces of the systems and
σ+π double aromatic in nature. The first two vertical one-electron detachment energies of M@B10− (M=Ag, Au) anions and first two ionization potentials of M@B9 (M=Ag, Au) and M@B10 (M=Cd, Hg) neutrals were calculated to aid future experiments. The cluster complexes designed in this work may expend the
domain of planar hyper-coordinate elements to include heavy group 11, 12, and 13 metals and serve as interesting candidates
to be targeted in experiments.
Electronic Supplementary Material Supplementary material is available for this article at and is accessible for authorized users.
Supported by the National Natural Science Foundation of China (Grant No. 20873117) 相似文献
993.
It was found that the interface effects in viscous capillary flow influenced the process of viscosity measurement greatly,and the abnormal viscosity behaviors of polyelectrolytes as well as neutral polymers in dilute solution region were ascribed to interface effect.According to this theory,we have reviewed the previous viscosity data of derivatives of poly-2- vinylpyridine reported by Maclay and Fuoss first.Then,the abnormal viscosity behaviors of a series of sodium polystyrene sulfonate samples with various molecular weights in dilute aqueous solutions were studied further.The solute adsorption behaviors and structural information of polymers have been discussed carefully. 相似文献
994.
Anguo Ying Ming Zheng Haidan Xu Fangli Qiu Changhua Ge 《Research on Chemical Intermediates》2011,37(8):883-890
An efficient and facile protocol for aza-Michael addition of aliphatic and aromatic amines to electron-deficit alkenes using
[TMG][Lac] as catalyst under solvent-free conditions was established. 相似文献
995.
996.
Jian-Kun Sun Linlin Zhang Liang Yue Tang Tang Wen-Jie Jiang Yun Zhang Zhenxiao Pan Xinhua Zhong Jin-Song Hu Li-Jun Wan 《中国科学:化学(英文版)》2018,61(10):1338-1344
Developing efficient counter electrodes (CEs) and quantum dots made of earth-abundant and non-toxic elements is essential but still challenging for quantum dot-sensitized solar cells (QDSSCs). Here, we report a facile strategy to prepare self-supported and robust CoS2 and NiS nanocrystals-assembled nanosheets directly grown on carbon paper (MSx NS@CP) as efficient counter electrodes for QDSSCs. Such CEs integrate the merits of fast electron transfer from interconnected conductive scaffold, efficient mass transfer from hierarchically vertical nanosheet on 3D open substrate, as well as abundant highly active catalytic sites from metal sulphide nanocrystal units. As a result, QDDSCs based on such CoS2 NS@CP and NiS NS@CP CEs achieve a PCE of 8.88% and 7.53%, respectively. The detailed analyses suggest that CoS2 NS@CP has the highest catalytic activity and shows the lowest charger transfer resistance, leading to the highest PCE. These findings may inspire the design and exploration of other self-supported efficient CEs by integrating highly active catalysts onto 3D conductive networks for efficient QDSSCs. 相似文献
997.
998.
Zhicheng Wang Yaw D. Yeboah Tiejun Bai Kofi B. Bota 《Plasma Chemistry and Plasma Processing》2004,24(3):405-420
Given the operational constraints of aerospace ground equipments (AGE), the nonthermal plasma discharge (NTPD) has been identified as a promising technology for their NOx removal. As part of a program to optimize an NTPD system for this particular application, an investigation of the effect of discharge gap spacing on the electrical and chemical processes that occur in NTPDs was initiated. A number of experiments were performed to examine how the gap spacing affects the NO removal efficiency, discharge characteristics, and chemical reactions in a NTPD device. Gap spacings ranging from 0.8 to 4.0 mm were investigated in this study. An optimum gap spacing for NO removal was observed at approximately 2 mm and, based on the experimental data, a physical explanation for the optimum was developed. The experiments, results and conclusions are discusssed in detail in this paper. 相似文献
999.
Geng ZhiYuan Yao Kun Wang YongCheng Fang Ran Zhang XingHui Jia BaoLi 《中国科学B辑(英文版)》2007,50(3):335-344
The mechanisms of theion reaction of alkylidenegermylene with oxirane and thiirane have been characterized detail in using density functional theory, as well as ab initio method, including geometry optimization and vibrational analysis for the involved stationary points on the potential energy surface. Energies were calculated by CCSD(T)/6-311G(d)//B3LYP/6-311G(d,p) method for the involved conformations. The results show that the reaction pathways for both reactions consist of two ways: (1) the reactants can yield bent products (P1; P4) by syn-isomers; (2) the reactants can also yield three-membered products (P2; P5) by anti-isomers, which then further react with oxirane and thiirane to form the ultimate products (P3-1, P3-2; P6). Furthermore, a comparison with alkylidenecarbene, oxirane, and thiirane was done. 相似文献
1000.
Cui-Hua Wang Guo-Feng Li Yan Wu Yu Wang Jie Li Duan Li Ning-Hui Wang 《Plasma Chemistry and Plasma Processing》2007,27(1):65-83
Algae in drinking water supplies often bring about impact on the water treatment. In this study, a bipolar pulsed dielectric
barrier discharge system in three-phase discharge plasma reactor was constructed for investigating its ability to control
excessive growth of cyanobacteria, Microcystis aeruginosa. Experimental results show there was almost no change in optical density immediately after the interruption of electrical
discharge, but the decreasing trend of optical density, cell density and chlorophyll-a content was obvious during the incubation period, indicating a significant residual effect of electrical discharge process
on the algal growth inhibition. Scanning electron microscopy investigation of algae revealed surface damage, apparent leakage
of intracellular contents and pores formed after electrical discharge process, which showed that algal cells had no potential
to survive and grow. Compared with the control sample, it was observed that electrical discharge on the algal extracellular
products has almost no residual effect and the growth rate of algae slightly decreased before three days storage. Hydrogen
peroxide was produced by electrical discharge in the μM level and showed a first-order decay. But at such level, the external
addition of hydrogen peroxide alone is not likely to cause the residual effect. These results implicated that the growth inhibition
of M. aeruginosa was mainly caused by electrical discharge process, and it made the algal cells lose ability to survive, demonstrating the
considerable potential of such an alternative process for efficient water purification. 相似文献