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181.
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Nguyen Ngoc Dong Quan 《Monatshefte für Mathematik》2012,168(2):191-214
We give a sufficient condition using the Brauer?CManin obstruction under which certain quartic curves have no rational points. Using this sufficient condition, we construct two families of genus one quartic curves violating the Hasse principle explained by the Brauer?CManin obstruction. 相似文献
183.
Pua Aileen Goh Rui Min Vivian Ee Kim-Huey Huang Yunle Liu Shao Quan Lassabliere Benjamin Yu Bin 《Chromatographia》2021,84(5):507-515
Chromatographia - The separation of isomers is one of the key issues in analysing complex natural matrices, thus commanding a higher separating power from the applied analytical system. In this... 相似文献
184.
Wang Zhongtang Wen Wei Quan Wei Du Liang Wang Ping Lin Jinxian Xie Yun Tan Zhaoyi 《Journal of Radioanalytical and Nuclear Chemistry》2018,316(1):411-417
Journal of Radioanalytical and Nuclear Chemistry - Plutonium is one of the key radionuclides in nuclear decommission. In this study, a rapid method was developed to analyze Pu for concrete samples... 相似文献
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Domino Radical Addition/Oxidation Sequence with Photocatalysis: One‐Pot Synthesis of Polysubstituted Furans from α‐Chloro‐Alkyl Ketones and Styrenes
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Shuang Wang Wen‐Liang Jia Lin Wang Prof. Dr. Qiang Liu Prof. Dr. Li‐Zhu Wu 《Chemistry (Weinheim an der Bergstrasse, Germany)》2016,22(39):13794-13798
A new domino reaction has been developed that allows the combination of styrenes and α‐alkyl ketone radicals to afford a wide array of polysubstituted furans in good to excellent yields under mild and simple reaction conditions. The key to success of this novel protocol is the use of photocatalyst fac‐Ir(ppy)3 and oxidant K2S2O8. Mechanistic studies by a radical scavenger and photoluminescence quenching suggest that a radical addition/oxidation pathway is operable. 相似文献
187.
Zhonggang Zhang Danting Yue Changrong He Shuang Ye Weiguo Wang Jinliang Yuan 《Heat and Mass Transfer》2014,50(11):1575-1586
In this study, a three-dimensional computational fluid dynamics model has been developed for an anode-supported planar SOFC. The conservation equations of mass, momentum, species/charges and thermal energy are solved by finite volume method for a complete unit cell consisting of 13 parallel channels in both anode and cathode. The simulation results of the developed model are well in agreement with the experimental data obtained at same conditions. In this study, the co-flow arrangement with hydrogen utilization of 60 % and operating voltage of 0.7 V is used as the base case, and compared with the counter-flow arrangement. The predicted results reveals that the maximum temperature obtained in the counter-flow arrangement is about 10 °C lower than that of co-flow, but the counter-flow arrangement has a higher temperature gradient between the respective anodes and cathodes in a cross-section normal to the main flow direction, especially in the air inlet region of the cell (x = 0.04 m),which is very harmful to the lifetime of materials. The current density is very unevenly distributed along and normal to the flow direction for both the co- and counter-flow arrangements, and the maximum values occur at junctions of the electrodes, channels and ribs, which causes higher over-potentials and ohmic heating. 相似文献
188.
Da Quan Zhang Xing Jin Bin Xie Hyung Goun Joo Li Xin Gao Kang Yong Lee 《Surface and interface analysis : SIA》2012,44(1):78-83
The corrosion inhibition of ammonium heltamolybdate (AH) and calcium gluconate (CG) for AA6061 alloy in 3% NaCl solution was investigated by the electrochemical measurements. It indicates that AH inhibits the corrosion of AA6061 alloy and acts as an anodic inhibitor. Maximum inhibition efficiency reaches 74.3% at the concentration of 1 × 10?4 mol.l?1 AH. The results of the electrochemical studies reveal AH is physically adsorbed on the AA6061 alloy surface and the adsorption follows Langmuir isotherm. The combination of AH and CG enhances the inhibition efficiency to 95.9%. The enhanced inhibition is attributed to the promotion of AH adsorption by CG. The mixture of AH and CG is a mixed‐type inhibitor and renders the corrosion potential to more positive values. Copyright © 2011 John Wiley & Sons, Ltd. 相似文献
189.
Dr. Zhen Lei Zong‐Jie Guan Dr. Xiao‐Li Pei Shang‐Fu Yuan Xian‐Kai Wan Jin‐Yuan Zhang Prof.Dr. Quan‐Ming Wang 《Chemistry (Weinheim an der Bergstrasse, Germany)》2016,22(32):11156-11160
A red–near‐IR dual‐emissive nanocluster with the composition [Au10Ag2(2‐py?C≡C)3(dppy)6](BF4)5 ( 1 ; 2‐py?C≡C is 2‐pyridylethynyl, dppy=2‐pyridyldiphenylphosphine) has been synthesized. Single‐crystal X‐ray structural analysis reveals that 1 has a trigonal bipyramidal Au10Ag2 core that contains a planar Au4(2‐py?C≡C)3 unit sandwiched by two Au3Ag(dppy)3 motifs. Cluster 1 shows intense red–NIR dual emission in solution. The visible emission originates from metal‐to‐ligand charge transfer (MLCT) from silver atoms to phosphine ligands in the Au3Ag(dppy)3 motifs, and the intense NIR emission is associated with the participation of 2‐pyridylethynyl in the frontier orbitals of the cluster, which is confirmed by a time‐dependent density functional theory (TD‐DFT) calculation. 相似文献
190.