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A facile approach to asymmetrical biaryls via coupling reaction of aryl halides with sodium tetraphenylborate catalyzed by MCM-41-supported sulfur palladium(0) complex

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Chinese Chemical Letters 2007年第4期18卷 387-389页

作者： Qiu Hua Xu ping ping Wang Ming Zhong cai Department of Chemistry Jiangxi Normal University 330027 Nanchang China Department of Chemistry Jiujiang University 332000 Jiujiang China

Various functionalized asymmetrical biaryls can be synthesized in high to excellent yields via coupling reaction of aryl iodides or bromides with NaBPh4 catalyzed by MCM-41-supported sulfur palladium（0） complex. Thi... 详细信息

关键词： Asymmetrical biaryl NaBPh4 Aryl halide Palladium Coupling reaction

Decoding the electron dynamics in high-order harmonic generation from asymmetric molecular ions in elliptically polarized laser fields

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Chinese Physics B 2022年第4期31卷 287-292页

作者： cai-ping Zhang Xiang-Yang Miao College of Physics and Information Engineering Shanxi Normal UniversityTaiyuan 030031China Key Laboratory of Spectral Measurement and Analysis of Shanxi Province Shanxi Normal UniversityTaiyuan 030031China

The high-order harmonic generation from an asymmetric molecular ion is theoretically investigated based on the Born-Oppenheimer model with two-dimensional electron *** is shown that the harmonic intensity changes periodically in elliptically polarized laser *** periodical character is *** establishing the physical image,the periodicity of the harmonic intensity can be ascribed to the contributions of the ground state and the excited ***,the electron dynamics from different electronic states can be selected via combining the elliptically polarized laser field with a static electric *** harmonics dominated either by ground state or excited state are emitted once in an optical cycle in the combined laser field.

关键词： asymmetric molecular ion high-order harmonic generation electron dynamics elliptically polarized laser field

Determining N supplied sources and N use efficiency for peanut under applications of four forms of N fertilizers labeled by isotope^15N

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Journal of Integrative Agriculture 2016年第2期15卷 432-439页

作者： WANG cai-bin ZHENG Yong-mei SHEN Pu ZHENG Ya-ping WU Zheng-feng SUN Xue-wu YU Tian-yi feng Hao Shandong Peanut Research Institute Qingdao 266100 P.R.China

Rational application of different forms of nitrogen（N） fertilizer for peanut（Arachis hypogaea L.） requires tracking the N supplied sources which are commonly not available in the differences among the three sources：root nodule,soil and *** this study,two kinds of peanut plants（nodulated variety（Huayu 22） and non-nodulated variety（NN-1）） were choosed and four kinds of N fertilizers：urea-N（CONH_2-N）,ammonium-N（NH_4~＋-N）,nitrate-N（NO_3^--N） and NH_4~＋＋NO_3^--N labeled by^（15）N isotope were applied in the field barrel experiment in Chengyang Experimental Station,Shandong Province,China,to determine the N supplied sources and N use efficiency over peanut growing *** results showed that intensities and amounts of N supply from the three sources were all higher at middle growing stages（pegging phase and podding phase）.The accumulated amounts of N supply from root nodule,soil and fertilizer over the growing stages were 8.3,5.3 and 3.8g m^（-2） in CONH_2-N treatment,which are all significantly higher than in the other three *** seedling phase,soil supplied the most N for peanut growth,then root nodule controlled the N supply at pegging phase and podding phase,but soil mainly provided N again at the last stage（pod filling phase）.For the whole growing stages,root nodule supplied the most N（47.8 and 43.0%） in CONH_2-N and NH_4~＋-N treatments,whereas soil supplied the most N（41.7 and 40.9%） in NH_4~＋＋NO_3^--N and NO_3^--N *** N use efficiency was higher at pegging phase and podding phase,while accumulated N use efficiency over the growing stages was higher in CONH_2-N treatment（42.2%） than in other three treatments（30.4%in NH_4~＋-N treatment,29.4%in NO_3^--N treatment,29.4%in NH_4~＋＋NO_3^--N treatment）.In peanut growing field,application of CONH_2-N is a better way to increase the supply of N from root nodule and improve the N use efficiency.

关键词： urea-N growing stage N fixation N use efficiency root nodule

Ground State and Single Vortex for Bose-Einstein Condensates in Anisotropic Traps

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Communications in Theoretical Physics 2007年第6期47卷 1053-1057页

作者： XU Zhi-Jun cai ping-Gen Department of Applied Physics Zhejiang University of Technology Hangzhou 310032 China The State Key Laboratory of Magnetic Resonance and Atomic and Molecular Physics Wuhan 430071 China

For Bose-Einstein condensation of neutral atoms in anisotropic traps at zero temperature, we present simple analytical methods for computing the properties of ground state and single vortex of Bose-Einstein condensates, and compare those results to extensive numerical simulations. The critical angular velocity for production of vortices is calculated for both positive and negative scattering lengths a, and find an analytical expression for the large-N limit of the vortex critical angular velocity for a 〉0, and the critical number for condensate population approaches the point of collapse for a 〈 0, by using approximate variational method.

关键词： Bose-Einstein condensation G-P equation wave function vortex formation

Helicity Amplitude Analysis of η_c Decays into Hyperon-Antihyperon Pairs

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Communications in Theoretical Physics 2009年第6期51卷 1091-1094页

作者： PANG cai-Ying ping Rong-Gang Institute of High Energy Physics Chinese Academy of Sciences P.O. Box 918（1） Beijing 100049 China College of Physics and Electronic Engineering Guangxi Normal University Guilin 541004 China Liuzhou High School Liuzhou 545006 China

The helicity amplitudes for the processes of e^＋e^- →J/ψ→γηc→γYY（Y： hyperon） are presented, together with the joint angular distributions for ηc decays into ∧∧,∑^0 ∑^0, and [1]-[1]＋. The sensitivities to measure the hyperon decay parameters in these decays are evaluated based on the helicity amplitudes. The prospects to test the Bell inequality in experiment using the decay of ηc→∧∧ are discussed.

关键词： ηc helicity amplitude hyperon decay parameter Bell inequality

Isolation and identification of bacteria responsible for simultaneous anaerobic ammonium and sulfate removal

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Science China Chemistry 2010年第3期53卷 644-649页

作者： cai, Jing Jiang, Jian Xiang Zheng, ping Department of Environmental Engineering Zhejiang University Hangzhou 310029 China

Sulfate-dependent anaerobic ammonium oxidation is a novel biological reaction,in which ammonium is oxidized with sulfate as the electron acceptor under anoxic *** and sulfate are cosmopolitan chemical species which are an integral part of the global nitrogen and sulfur cycles.A detailed exploration of sulfate-dependent anaerobic ammonium oxidation is quite *** this work,a bacterial strain named ASR has been isolated from an anaerobic ammonia and sulfate removing reactor working under *** the basis of electron microscopy,physiological tests and 16S rDNA phylogenetic sequence analysis,the strain ASR is found to be related to Bacillus *** to the biological carbon source utilization test,the strain ASR could use many carbon *** optimum pH value and temperature were 8.5 and 30 °C,*** test proves that the strain ASR is able to use sulfate to oxidize ammonia *** maximum ammonia and sulfate removal rates were 44.4% and 40.0%,*** present study provided biological evidence for the confirmation and development of sulfate-dependent anaerobic ammonium oxidation and brought new insights into the global nitrogen and sulfur cycles.

关键词： bacillus ammonia sulfate isolation and identification

Characteristics and implications of stress state in a gold mine in Ludong area, China

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International Journal of Minerals,Metallurgy and Materials 2018年第12期25卷 1363-1372页

作者： Peng Li Mei-feng cai Qi-feng Guo Sheng-jun Miao School of Civil and Resource Engineering University of Science and Technology Beijing Key Laboratory of High-Efficient Mining and Safety of Metal Mines (Ministry of Education of China) University of Science and Technology Beijing Beijing Key Laboratory of Urban Underground Space Engineering University of Science and Technology Beijing

In this study, we obtained information from twenty-one measurement points on the stress magnitudes and orientations of a gold mine in the Ludong area. We used the overcoring technique with an improved hollow inclusion strain gauge and then analyzed the distribution characteristics of the in situ stress field. The results indicate that the stress field is characterized by σH > σh > σv and σH > σv > σh(where σH, σh, and σv are the maximum horizontal, minimum horizontal, and vertical principal stresses, respectively). The regional stress field is dominated by horizontal principal stress. The σH, σh, and σv values show a gradual increasing trend with depth. The σH is predominantly oriented in the NWW–SEE or near-EW direction. We also confirmed the correspondence between the measured stress field and the regional geological structure. In addition, based on the measured stress data, we discuss the implications of the in situ stress with respect to fault activity in the mine area.

关键词： in situ stress measurement improved hollow inclusion strain gauge stress field geological structure fault activity

Numerical Simulation for Accuracy of Velocity Analysis in Small-Scale High-Resolution Marine Multichannel Seismic Technology

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Journal of Ocean University of China 2017年第3期16卷 370-382页

作者： LUO Di cai feng WU Zhiqiang The Key Laboratory of Gas Hydrate Ministry of Land and ResourcesQingdao Institute of Marine Geology Laboratory for Marine Mineral Resources Qingdao National Laboratory for Marine Science and Technology

When used with large energy sparkers, marine multichannel small-scale high-resolution seismic detection technology has a high resolution, high-detection precision, a wide applicable range, and is very flexible. Positive results have been achieved in submarine geological research, particularly in the investigation of marine gas hydrates. However, the amount of traveltime difference information is reduced for the velocity analysis under conditions of a shorter spread length, thus leading to poorer focusing of the velocity spectrum energy group and a lower accuracy of the velocity analysis. It is thus currently debatable whether the velocity analysis accuracy of short-arrangement multichannel seismic detection technology is able to meet the requirements of practical application in natural gas hydrate exploration. Therefore, in this study the bottom boundary of gas hydrates(Bottom Simulating Reflector, BSR) is used to conduct numerical simulation to discuss the accuracy of the velocity analysis related to such technology. Results show that a higher dominant frequency and smaller sampling interval are not only able to improve the seismic resolution, but they also compensate for the defects of the short-arrangement, thereby improving the accuracy of the velocity analysis. In conclusion, the accuracy of the velocity analysis in this small-scale, high-resolution, multi-channel seismic detection technology meets the requirements of natural gas hydrate exploration.

关键词： small-scale high-resolution multichannel seismic velocity analysis accuracy gas hydrate

Equilibrium of Organic Matter in Heavy Fraction for Three Long-term Experimental Field Soils in China

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Pedosphere 2006年第2期16卷 177-184页

作者： YIN Yun-feng cai Zu-Cong State Key Laboratory of Soil and Sustainable Agriculture Institute of Soil Science Chinese Academy of Sciences Nanjing 210008 （China）.

Considerable evidence that the soil organic matter （OM） level in agricultural soils will gradually over time reach an equilibrium state under certain bioclimatic conditions and for certain cropping systems has been accumulating. Although models or long-term experiments have been used, this research used physical fractionation procedure to attain an soil OM equilibrium value. To obtain soil OM equilibrium values in the heavy fraction, typical soils from three long-term field experiments at fengqiu and Yingtan State Key Agro-Ecological Experimental Stations in China were studied using a simple density fractionation procedure and employing the Langmuir equation. Results for the fluvo-aquic soil with organic fertilizer treatments indicated that the soil OM equilibrium value in the heavy fraction was twofold more than that in the inorganic treatments; however, for the paddy soil developed on red soil the OM equilibrium value in the heavy fraction for both treatments was almost identical. It suggested that for fiuvo-aquic soils the increased potential of OM for the heavy fraction in the long run was larger for the organic than the inorganic fertilizer applications, whereas for paddy soils developed on red soils under the same conditions the present OM content in the heavy fraction was at or close to this equilibrium level for all treatments, and increased potential was very limited.

关键词： equilibrium value heavy fraction Langmuir equation soil organic matter