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971.
Using the standard reductive perturbation technique,a nonlinear Schroedinger equation is derived to study the modulational instability of finite-amplitude ion-acoustic waves in a non-magnetized warm plasma.It is found that the inclusion of ion temperature in the equation modifies the nature of the ion-acoustic wave stability and the soliton stuctures.The effects of ion plasma temperature on the modulational stability and ion-acoustic wave properties are inestigated in detail. 相似文献
972.
Jia‐Geng Liu Jing‐Jing Nie Duan‐Jun Xu Yuan‐Zhi Xu Jing‐Yun Wu Michael Y. Chiang 《Acta Crystallographica. Section C, Structural Chemistry》2001,57(4):354-355
The title complex, [CuCl2(C6H6N4S2)], has a flattened tetrahedral coordination. The CuII atom is located on a twofold rotation axis and is coordinated by two N atoms from a chelating 2,2′‐diamino‐4,4′‐bi‐1,3‐thiazole ligand and by two Cl atoms. Intramolecular hydrogen bonding exists between the amino groups of the 2,2′‐diamino‐4,4′‐bi‐1,3‐thiazole ligand and the Cl atoms. The intermolecular separation of 3.425 (1) Å between parallel bithiazole rings suggests there is a π–π interaction between them. 相似文献
973.
974.
975.
段芳芳 杨彦云 庞丹阳 胡碧涛 王建松 王康 杨过 Valdir Guimar?es 马朋 许世伟 刘星泉 马军兵 白真 胡强 金树亚 孙欣欣 姚佳盛 齐航凯 孙志宇 《中国物理C(英文版)》2020,(2):72-79
Elastic scattering of 10Be on a 208Pb target was measured at ELab=127 MeV,which corresponds to three times the Coulomb barrier.The secondary 10Be beam was produced at the Radioactive Ion Beam Line in Lanzhou of the Heavy-Ion Research Facility in Lanzhou.The angular distribution of elastic scattering in the 10 Be+208Pb system shows a typical Fresnel diffraction peak.Optical model analysis of the angular distribution was performed using the Woods-Saxon,double-folding and global potentials.With the global potential,different density distributions were used.The results indicate that different density distributions for the projectile induce distinct effects in the angular distribution. 相似文献
976.
Zong‐Jin Pu Shi‐Jun Yue Hui Yan Yu‐Ping Tang Yan‐Yan Chen Ya‐Jie Tan Xu‐Qin Shi Zhen‐Hua Zhu Hui‐Juan Tao Jia‐Qian Chen Gui‐Sheng Zhou Sheng‐Liang Huang Guo‐Ping Peng Shu‐Lan Su Jin‐Ao Duan 《Journal of separation science》2020,43(16):3170-3182
Safflower has both medicinal and edible values but research on its nutrient composition is still lacking. This study was established for the quantitative determination of 28 nucleosides, nucleobases, and amino acids based on the ultra‐performance liquid chromatography coupled with triple‐quadrupole linear ion‐trap tandem mass spectrometry. Analysis of 30 batches of safflower from different producing areas indicated that the contents of l ‐proline, l ‐asparagine, l (+)‐arginine, l ‐serine, l ‐histidine, uracil, guanosine, and uridine was high in safflower. Principle component analysis and cluster analysis found that samples from different regions could be distinguished well, and samples from the same area could be clustered into one class, different geographical environments may cause the differences of nucleosides, nucleobases, and amino acids in safflower. The analysis of principal component analysis, cluster analysis, and counter propagation artificial neural network show similar results. Then the content of nucleosides, nucleobases, and essential amino acids were compared, and found that the content in safflower from Gansu was higher than those from other regions, and there was a little difference between the samples from Xinjiang, Sichuan, and Yunnan. This research revealed the composition of nucleosides, nucleobases, and amino acids in safflower, and provided a theoretical basis for utilization of safflower. 相似文献
977.
Di Xiao Xiaojiang Duan Qianqian Gan Xuran Zhang Junbo Zhang 《Molecules (Basel, Switzerland)》2020,25(23)
Prostate-specific membrane antigen (PSMA) is a well-established biological target that is overexpressed on the surface of prostate cancer lesions. Radionuclide-labeled small-molecule PSMA inhibitors have been shown to be promising PSMA-specific agents for the diagnosis and therapy of prostate cancer. In this study, a glutamate-urea-based PSMA-targeted ligand containing an isonitrile (CNGU) was synthesized and labeled with 99mTc to prepare [99mTc]Tc-CNGU with a high radiochemical purity (RCP). The CNGU ligand showed a high affinity toward PSMA (Ki value is 8.79 nM) in LNCaP cells. The [99mTc]Tc-CNGU exhibited a good stability in vitro and hydrophilicity (log P = −1.97 ± 0.03). In biodistribution studies, BALB/c nude mice bearing LNCaP xenografts showed that the complex had a high tumor uptake with 4.86 ± 1.19% ID/g, which decreased to 1.74 ± 0.90% ID/g after a pre-injection of the selective PSMA inhibitor ZJ-43, suggesting that it was a PSMA-specific agent. Micro-SPECT imaging demonstrated that the [99mTc]Tc-CNGU had a tumor uptake and that the uptake was reduced in the image after blocking with ZJ-43, further confirming its PSMA specificity. All of the results in this work indicated that [99mTc]Tc-CNGU is a promising PSMA-specific tracer for the imaging of prostate cancer. 相似文献
978.
Dr. Yueqiang Cao Hao Zhang Dr. Shufang Ji Prof. Zhijun Sui Prof. Zheng Jiang Prof. Dingsheng Wang Prof. Francisco Zaera Prof. Xinggui Zhou Prof. Xuezhi Duan Prof. Yadong Li 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2020,132(28):11744-11749
Atomic regulation of metal catalysts has emerged as an intriguing yet challenging strategy to boost product selectivity. Here, we report a density functional theory-guided atomic design strategy for the fabrication of a NiGa intermetallic catalyst with completely isolated Ni sites to optimize acetylene semi-hydrogenation processes. Such Ni sites show not only preferential acetylene π-adsorption, but also enhanced ethylene desorption. The characteristics of the Ni sites are confirmed by multiple characterization techniques, including aberration-corrected high-resolution scanning transmission electron microscopy and X-ray absorption spectrometry measurements. The superior performance is also confirmed experimentally against a Ni5Ga3 intermetallic catalyst with partially isolated Ni sites and against a Ni catalyst with multi-atomic ensemble Ni sites. Accordingly, the NiGa intermetallic catalyst with the completely isolated Ni sites shows significantly enhanced selectivity to ethylene and suppressed coke formation. 相似文献
979.
Zhang Bo Wang Haiying Yan Xuechao Duan Yu-Ai Guo Shuai Luo Fei-Xian 《Transition Metal Chemistry》2020,45(2):99-110
Transition Metal Chemistry - A series of ruthenium [NNN]- or [NCN]-type complexes (3–7) bearing PPh3 ancillary ligands have been synthesized from pyridine- or phenylene-bridged bis(triazoles)... 相似文献
980.
Cheng Zheng Li Jinpeng Wang Bin Zeng Jinsong Xu Jun Zhu Shiyun Duan Chengliang Chen Kefu 《Cellulose (London, England)》2022,29(13):7083-7098
Cellulose - Nanocellulose, a unique and promising nanosized cellulose fibers extracted from renewable biomass, has gained much attention from both the scientific and industrial communities due to... 相似文献