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Benzylation of arenes and heteroarenes catalyzed by HfCl_4/HfO_2

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Chinese Chemical Letters 2009年第8期20卷 913-916页

作者： Cheng Yi zhang Xin Qin Gao Jiang Hua zhang xiao jun Peng State Key Laboratory of Fine Chemicals Dalian University of Technology Dalian 116012 China

A highly efficient benzylation of arenes and heteroarenes catalyzed by HfCl4/HfO2 has been developed. Broad scope of benzylation reagents have been used in this process with high yields under mild condition. Additionally, the HfO2 can be re-used after the reaction. ？2009 Xin Qin Gao. Published by Elsevier B.V. on behalf of Chinese Chemical Society. All rights reserved.

关键词： Benzylation Hafnium chloride Hafnium oxide Benzylation reagents

Effect of chip rate on the ranging accuracy in a regenerative pseudo-noise ranging system

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Journal of Zhejiang University-Science C(Computers and Electronics) 2011年第2期12卷 132-139页

作者： Jian-wen JIANG Wei-jun YANG Chao-jie zhang xiao-jun JIN Zhong-he JIN Department of Information Science and Electronic Engineering Zhejiang University Hangzhou 310027 China

The ranging accuracy of a pseudo-noise ranging system is mainly decided by range jitter and time delay discrimination. Many factors can affect the ranging accuracy, one of which is the chip rate. In digital signal processing, the time delay discrimination and autocorrelation function of sampled ranging sequences of different chip rates are very different. An approximation simulation model is established according to an in-phase quadrature (I/Q) correlator which is used to evaluate the time delay. Simulation results of the range jitter and time delay discrimination show that the chip rate which provides a non-integer sample-to-chip rate ratio can achieve a higher ranging accuracy, and some test results validate the simulation model. In some design missions, the simulation results may help to select an optimum sample-to-chip rate ratio to satisfy the design requirement on the ranging accuracy.

关键词： Ranging accuracy Range jitter Time delay discrimination Sample-to-chip rate ratio Integration time Autocorrelation function Fractional chip period delay

A novel way to synthesize Pb nanotapes in liquid ammonia

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Chinese Chemical Letters 2011年第8期22卷 993-996页

作者： Lei Sun Meng Lei zhang xiao jun Tao Yan Bao Zhao Key Laboratory for Special Functional Materials of Ministry of Education Henan University Kaifeng 475004 China

Lead nanotapes were synthesized in liquid ammonia solvent in the presence of sodium metal at low *** process was template *** electron microscopy（TEM） observations and X-ray diffraction（XRD） characterizations revealed that the as-prepared Pb nanotapes have average diameters in the range of 40-50 *** lengths up to several hundred nanometers, and exhibit cubic crystal structures.

关键词： Pb Nanotapes Chemical synthesis Liquid ammonia

Inclusion of peanut in wheat–maize rotation increases wheat yield and net return and improves soil organic carbon pool by optimizing bacterial community

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Journal of Integrative Agriculture 2023年第11期22卷 3430-3443页

作者： ZOU xiao-xia HUANG Ming-ming LIU Yan SI Tong zhang xiao-jun YU xiao-na GUO Feng WAN Shu-bo Shandong Provincial Key Laboratory of Dryland Farming Technology/Shandong Peanut Industry Collaborative Innovation Center/College of Agronomy Qingdao Agricultural UniversityQingdao 266109P.R.China Institute of Crop Germplasm Resources Shandong Academy of Agricultural SciencesJinan 250100P.R.China

Improving soil quality while achieving higher productivity is the major challenge in the agricultural industry. Wheat(Triticum aestivum L.)–maize(Zea mays L.)(W–M) rotation is the dominant planting pattern in the Huang-HuaiHai Plain and is important for food security in China. However, the soil quality is deteriorating due to the W–M rotation’s long-term, intensive, and continuous cultivation. Introducing legumes into the W–M rotation system may be an effective way to improve soil quality. In this study, we aimed to verify this hypothesis by exploring efficient planting systems(wheat–peanut(Arachis hypogaea L.)(W–P) rotation and wheat rotated with maize and peanut intercropping(W–M/P)) to achieve higher agricultural production in the Huang-Huai-Hai Plain. Using traditional W–M rotation as the control, we evaluated crop productivity, net returns, soil microorganisms(SMs), and soil organic carbon(SOC) fractions for three consecutive years. The results indicated that wheat yields were significantly increased under W–P and W–M/P(382.5–579.0 and 179.8–513.1 kg ha-1, respectively) compared with W–M. W–P and W–M/P provided significantly higher net returns(58.2 and 70.4%, respectively) than W–M. W–M/P and W–M retained the SOC stock more efficiently than W–P, increasing by 25.46–31.03 and 14.47–27.64%, respectively, in the 0–20 cm soil layer. Compared with W–M, W–M/P improved labile carbon fractions;the sensitivity index of potentially mineralizable carbon, microbial biomass carbon(MBC), and dissolved organic carbon was 31.5, 96.5–157.2, and 17.8% in 20–40, 10–40, and 10–20 cm soil layers, respectively. The bacterial community composition and bacteria function were altered as per the soil depth and planting pattern. W–M/P and W–M exhibited similar bacterial community composition and function in 0–20 and 20–40 cm soil layers. Compared with W–P, a higher abundance of functional genes, namely, contains mobile elements and stress-tolerant, and a lower abundance of genes, namely,

关键词： composite planting carbon sequestration labile carbon fraction bacterial community structure bacterial functions

High Efficiency Grating Coupler for Coupling between Single-Mode Fiber and SOI Waveguides

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Chinese Physics Letters 2013年第1期30卷 99-102页

作者： zhang Can SUN Jing-Hua xiao Xi SUN Wei-Min zhang xiao-jun CHU Tao YU Jin-Zhong YU Yu-De College of Science Harbin Engineering UniversityHarbin 150001 State Key Laboratory on Integrated Optoelectronics Institute of SemiconductorsChinese Academy of SciencesBeijing 100083

A high efficiency grating coupler between single-mode fiber and silicon-on-insulator waveguide is designed by a formula *** 78.5%coupling efficiency(>-1.05 dB)with 3 dB bandwidth about 50 nm for one grating coupler is obtained experimentally and this result is the highest one as far as we *** grating coupler is CMOS compatible which needs only one etch-step and is designed for a standard SOI chip without any Bragg reflector or bottom reflector.

关键词： SOI waveguide Efficiency

Cyclovirobuxinum D Alleviates Cardiac Hypertrophy in Hyperthyroid Rats by Preventing Apoptosis of Cardiac Cells and Inhibiting the p38 Mitogen-Activated Protein Kinase Signaling Pathway

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Chinese Journal of Integrative Medicine 2017年第10期23卷 770-778页

作者： WU jun-biao ZHOU Yuan LIANG Chun-ling zhang xiao-jun LAI Jie-mei YE Shu-fang OUYANG Hui LIN Jin ZHOU Jiu-yao The Second Affiliated Hospital of Guangzhou University of Chinese Medicine Guangzhou University of Chinese Medicine Department of Pharmacology College of Chinese Materia Medica Guangzhou University of Chinese Medicine Science and Technology Park Co. Ltd. Guangzhou University of Chinese Medicine

Objective： To investigate the underlying mechanisms of cyclovirobuxinum D（Cvb-D） on alleviating cardiac hypertrophy in rats. Methods： Sprague-Dawley rats were randomly divided into 5 groups： control group; levothyroxine-induced cardiac hypertrophy group（model）; levothyroxine-induced cardiac hypertrophy ＋ Cvb-D group（Cvb-D）; levothyroxine-induced cardiac hypertrophy ＋ captopril group（captopril）; levothyroxine-induced cardiac hypertrophy ＋ SB203580 group（SB203580）, n=10 for each group. Rats were daily administered the respective drugs continuously for14 days by gastric gavage. A rat model of cardiac hypertrophy was established by intraperitoneal injection of levothyroxine to investigate whether Cvb-D protects against cardiac hypertrophy by inhibiting the p38 mitogen-activated protein kinase（MAPK） signaling pathway and preventing apoptosis of cardiac cells. Results： Treatment with Cvb-D significantly deceased left ventricle hypertrophy, improved the histopathology, hemodynamic conditions, and cardiac function in rats with cardiac hypertrophy. Compared with the normal control group, in rats with cardiac hypertrophy, expression of bax in the heart and phospho-p38 MAPK protein levels were significantly up-regulated（P〈0.01 or 0.05）, whereas the bcl-2 protein level was downregulated（P〈0.01）. In contrast, Cvb-D treatment reversed the changes in bax and phospho-p38 MAPK protein levels but increased the bcl-2 protein level（P〈0.01 or 0.05）, and these effects were similar to those of captopril and SB203580（a specific p38 MAPK inhibitor） treatment. Furthermore, both Cvb-D, captopril and SB203580 reduced m RNA expression of p38α, p38β, c-fos, and c-jun m RNA, and Cvb-D had a stronger effect（P〈0.01）. Conclusion： These results demonstrate that Cvb-D protects against cardiac hypertrophy, which is possibly mediated by prevention of cardiac cell apoptosis and inhibition of the p38 MAPK signaling pathway.

关键词： hypertrophic cardiomyopathy cyclovirobuxinum D apotosis p38 mitogen-activated protein kinase Chinese medicine

Book Review: Metaphor: Embodied Cognition and Discourse Edited by Beate Hampe Cambridge University Press (2017) UK xii+369 pp. ISBN 9781108187480

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Journal of Literature and Art Studies 2021年第3期11卷 164-167页

作者： SHEN Lei zhang xiao-jun School of Foreign Languages Nanjing Xiao Zhuang UniversityNanjingP.R.C Xi’an Jiaotong-Liverpool University SuzhouP.R.C

The book under review presents a comprehensive investigation into Metaphor theories from perspectives of embodied cognition and *** sketching dimensions and dynamics of contemporary metaphor theories in the first part,it presents and evaluates metaphor in cognition by analyzing sources and target of the primary metaphor theory,the hierarchical structure of mental metaphors,metaphorical directionality and body schema in metaphorical *** of sign systems,modalities,contextualized discourse interaction patterns,embodied metonymy are included in the third *** metaphor in discourse in detailed research with multiple related topics is in the fourth *** embodied and discourse views of metaphor are highlighted in the epilogue,and it points out that one’s preferred level of analysis argues against the relevance of other perspectives on metaphor performance by using different methods.

关键词： metaphor embodied cognition discourse

LATTICE BGK MODEL FOR THE INCOMPRESSIBLE NAVIER-STOKES EQUATION

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Journal of Hydrodynamics 2003年第3期15卷 96-102页

作者： zhang xiao-jun, Liu Zu-yuan School of Transportation, Wuhan University of Technology, Wuhan 430063, China, School of Transportation Wuhan University of Technology Wuhan 430063 China

In this paper a Lattice Bhatager-Gross-Krook (LBGK) model to simulateincompressible flow is developed. The basic idea is to explicitly eliminate the compressible effect,due to the density fluctuation in the existing LBGK models. In the proposed incompressible LBGKmodel, the pressure p instead of the constant mass density ρ_0 is the independent dynamic *** incompressible Navier-Stokes equations are exactly derived from this incompressible LBGK *** order to test the LBGK model, the plane Poiseuille flow driven either by pressure gradient or afixed velocity profile at entrance as well as the 2-D Womersley flow are simulated. The numericalresults are found to be in excellent agreement with theory and the results of previous studies.

关键词： lattice BGK method incompressible navier-stokes equation poiseuilleflow wornersley flow

An Ionic Liquid-assisted Hydrothermal Synthesis of Ce02 Nanorods

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无机材料学报 2015年第3期30卷 325-329页

作者： CHEN Ting JIANG Wei-Hui zhang xiao-jun XIE Zhi-Xiang LIU Jian-Min JIANG Wan School of Material Science and Engineering Jingdezhen Ceramic Institute Jingdezhen 333001 China

CeO2 nanorods were synthesized by a hydrothermal method at 160℃ from CeC16-6H20 and NH3.H20 in the presence of an ionic liquid 1-butyl-3-methyl-imidazolium chloride （[Bmim]C1）. The phase and morphology of the result- ing products were characterized by X-ray diffraction （XRD） and high-resolution transmission electron microscopy （HRTEM）, respectively. The results reveal that morphology of CeO2 prepared in the presence of the ionic liquid is nano- rod while it changes to irregular nanoparticle without ionic liquid. The resulting nanorods are about 13-25 nm in diameter and 200-500 nm in length. With the increase of ionic concentration, nanorods were disappeared gradually and nanoparticles were obtained. Moreover, increasing the hydrothermal temperature to 180℃, nanospheres at size of 19-24 nm could be synthesized by aggregation of-2 nm nanocrystals.

关键词： cerium oxide soft template hydrothermal treatment ionic liquid nanorod