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Crystal Structure of Dimethylamine 3,5-Dinitrobenzoic Acid Organic Adduct

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Chinese Journal of Structural Chemistry 2006年第8期25卷 1011-1013页

作者： ZHU Jun zhang yun CHEN Hao CHE yun-Xia ZHENG Ji-Min Department of Chemistry Nankai University lianjin 300071 China

The title adduct （C9H11N3O6, Mr= 257.21） was synthesized and it crystallizes in orthorhombic, space group P212121 with a = 5.8835（19）, b =9.517（3）, c = 20.399（6） A, V= 1142.2（6） ,A^3 Z = 4, Dc= 1.496 g/cm^3, F（000） = 536,μ（MoKα） = 0.128 mm^-1, the final R = 0.0396 and wR = 0.0800 for 1047 observed reflections with I 〉 2σ（I）. The compound is a 1：1 adduct of dimethylamine and 3,5-dinitrobenzoic acid which are linked by hydrogen bonds to form a two-dimensional network. The dimethylamine is protonated at the nitrogen atom with the proton from the carboxyl of 3,5- dinitrobenzoic acid.

关键词： dimethylamine 3,5-dinitrobenzoic acid hydrogen bond crystal structure nonlinear optical

Numerical investigation of the influence of companion drops on drop-on-demand ink jetting

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2012年第8期13卷 584-595页

作者： Hai-yun zhang Jin WANG Guo-dong LU Institution of Engineering and Computer Graphics Zhejiang UniversityHangzhou 310027China

In this study we characterized and investigated the specific phenomenon of "companion drops" in the drop-ondemand(DOD) ink jetting process.A series of simulations based on a piezoelectric DOD printhead system is presented,adapting the volume-of-fluid(VOF) interface-capturing method to track the boundary evolution and model the interfacial *** results illustrate the causality between the generation of companion drops and droplet deviation behavior,as well as their close correlations with ink jetting straightness and printing *** characteristics of companion drops are summarized and compared with those of satellite ***,a theoretical mechanism for the generation of companion drops is presented,and their effects and behaviors are analyzed and ***,the effects of critical factors on the generation of companion drops are investigated and characterized based on variations in the printable pressure *** are given for the suppression of companion drops and for the improvement of printing accuracy.

关键词： Drop-on-demand (DOD) ink jetting Droplet deviation Companion drops Computational fluid dynamics (CFD) Volume-of-fluid (VOF) method

Explicit Piecewise Smooth Solutions of Landau-Lifshitz Equation with Discontinuous External Field

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Acta Mathematicae Applicatae Sinica 2009年第1期25卷 61-74页

作者： Gan-shan Yang yun-zhang zhang Li-min Liu Institute of Mathematics Science Yunnan Normal University Kunming 650092 China Department of Mathematics Yunnan National University Kunming 650031 China Faculty of Science Xi'an Jiaotong University Xi'an 710049 China College of Mathematics and Physics Chongqing University Chongqiong 400030 China

In this paper, we shall construct some explicit piecewise smooth （global continuous） solutions as well as blow up solutions to the multidimensional Landau-Lifshitz equation, subject to the external magnetic fields being both discontinuous and unbounded. When the external magnetic field is continuous, some explicit exact smooth solutions and blow up solution are also constructed. We also establish some necessary and sufficient conditions to ensure that the solution of multidimensional Landau-Lifshitz equation with external magnetic field converges to the solution of equation without external magnetic field when the external magnetic field tends to zero.

关键词： Multidimensional Landau-Lifshitz equation discontinuous external field piecewise smoothsolution

Effect of Fly Ash and Silica Fume on Hydration Rate of Cement Pastes and Strength of Mortars

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Journal of Wuhan University of Technology(Materials Science) 2014年第6期29卷 1225-1228页

作者：刘军 zhang yun 刘润清 zhang Bing School of Materials Science and Engineering Shenyang Ligong University Liaoning Lingyuan City Street Office

The effect of fly ash and silica fume on hydration rate and strength of cement in the early stage was studied. Contrast test was applied to the complex cementitious system to investigate the hydration rate. Combined with mechanical strength, the influence of fly ash and silica fume during the hydration process of complex binder was researched. The peak of the rate of hydration heat evolution and the mechanical strength decreased as the ratio of fly ash increased, however, as the ratio of silica fume increased, the peak of the rate of hydration heat evolution and the mechanical strength increased obviously. When the ratios of fly ash and silica fume are 10% and 5%, the peak of the rate of hydration heat evolution is the highest. At the same time 7 days of flexural and compressive strength are the highest as 8.89 MPa and 46.52 MPa, respectively. Fly ash and silica fume are the main factors affecting the hydration rate and the mechanical property.

关键词： fly ash silica fume flexural and compressive strength hydration rate

Precipitation Microphysical Processes in the Inner Rainband of Tropical Cyclone Kajiki (2019) over the South China Sea Revealed by Polarimetric Radar

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Advances in Atmospheric Sciences 2021年第1期38卷 65-80页

作者： Hepeng ZHENG yun zhang Lifeng zhang Hengchi LEI Zuhang WU College of Meteorology and Oceanography National University of Defense TechnologyNanjing 211101China Institute of Atmospheric Physics Chinese Academy of SciencesBeijing 100029China

Polarimetric radar and 2D video disdrometer observations provide new insights into the precipitation microphysical processes and characteristics in the inner rainband of tropical cyclone(TC)Kajiki(2019)in the South China Sea for the first *** precipitation of Kajiki is dominated by high concentrations and small(<3 mm)raindrops,which contribute more than 98%to the total *** average mass-weighted mean diameter and logarithmic normalized intercept are 1.49 mm and 4.47,respectively,indicating a larger mean diameter and a lower concentration compared to the TCs making landfall in eastern *** ice processes of the inner rainband are dramatically different among different *** riming process is dominant during the mature stage,while during the decay stage the aggregation process is *** vertical profiles of the polarimetric radar variables together with ice and liquid water contents in the convective region indicate that the formation of precipitation is dominated by warm-rain *** raindrops collect cloud droplets and other raindrops,causing reflectivity,differential reflectivity,and specific differential phase to increase with decreasing *** is,accretion and coalescence play a critical role in the formation of heavy *** melting of different particles generated by the ice process has a great influence on the initial raindrop size distribution(DSD)to further affect the warm-rain *** DSD above heavy rain with the effect of graupel has a wider spectral width than the region without the effect of graupel.

关键词： South China Sea cloud precipitation microphysics polarimetric radar tropical cyclone rainband

Reliability Modeling and Maintenance Policy Optimization for Deteriorating System Under Random Shock

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Journal of Shanghai Jiaotong university(Science) 2018年第6期23卷 791-797页

作者： Lv yi zhang yun School of Automation Guangdong University of TechnologyGuangzhou 510006China School of Computer Engineering University of Electronic Science and Technology of ChinaZhongshan Institute Zhongshan 528400GuangdongChina

Performance degradation and random shock are commonly regarded as two dependent competing risks for system failures. One method based on effective service age is proposed to jointly model the cumulative effect of random shock and system degradation, and the reliability model of degradation system under Nonhomogeneous Poisson processes(NHPP) shocks is derived. Under the assumption that preventive maintenance(PM) is imperfective and the corrective maintenance(CM) is minimal repair, one maintenance policy which combines PM and CM is presented. Moreover, the two decision variables, PM interval and the number of PMs before replacement,are determined by a multi-objective maintenance optimization method which simultaneously maximizes the system availability and minimizes the system long-run expect cost rate. Finally, the performance of the proposed maintenance optimization policy is demonstrated via a numerical example.

关键词： degradation random shock Nonhomogeneous Poisson processes(NHPP) imperfect preventive maintenance multi-objective optimization

Zoological Research shines in the East

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Zoological Research 2022年第1期43卷 1-2页

作者： Yong-Gang Yao yun zhang Institute of Zoology Chinese Academy of SciencesKunmingYunnan 650223China Kunming Institute of Zoology Chinese Academy of SciencesKunming Yunnan 650223China

With the long-term support of every friend and contributor,Zoological Research(ZR)has continued to move forward over the past year,with impressive ***,ZR attained an impact factor of 4.56(JCR Q1)and CiteScore of 4.6 in mid-2021,thus ranking in the top five of the 175 SCI journals within the Zoology *** November 2021,our Citescore reached 5.6,and we expect a higher impact factor in 2022 than in *** we are not driven by chasing these scores,the increase in these metrics does reflect an elevation in the quality of submissions and publications,as well as the march towards our original aspiration when launching this journal(Yao et al.,2019).The current areas of focus of ZR(i.e.,primate and animal models;animal diversity and evolution;conservation&utilization of animal resources)are not only tightly connected to our host-the Kunming Institute of Zoology,which has grown and evolved into“a comprehensive research institution renowned for its remarkable achievements in evolutionary mechanisms of animal biodiversity,animal resources protection,and sustainable utilization”(Yao&Shen,2019)-but also represent the very frontiers of zoology.

关键词： frontier journal utilization

Correlation between social support and depression in elderly stroke patients in the sequelae stage from five communities of Shanghai, China

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Neural Regeneration Research 2011年第19期6卷 1493-1497页

作者： Huiying zhang Ting Zhou Yaqing zhang Ying zhang yun Xu Nursing School of Shanghai Jiao Tong University Shanghai 200025 China

Using a convenience sampling method, 81 aged patients who were between 6 and 24 months post-stroke were selected from five communities of Shanghai, China. The correlations between social support and depression, as well as other influential factors, were investigated. Results revealed that 46% （37/81） of the stroke patients suffered from depression. Depression was correlated with social support total scores and the two domains of subjective support and utilization. Older age, male gender, low income, absence of spouse and cerebral hemorrhage were risk factors for depression and identify more vulnerable groups.

关键词： community aged patients stroke depression social support

Expression of midkine and its clinical significance in esophageal squamous cell carcinoma

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World Journal of Gastroenterology 2006年第13期12卷 2006-2010页

作者： Ying-Jia Ren Qing-yun zhang Department of Immunology The School of Ontology Peking University Beijing Institute for Cancer Research Beijing 100036 China Department of Medical Laboratory Beijing Cancer Hospital Beijing 100036 China

AIM： To investigate the expression of midkine in eso- phageal squamous cell carcinoma （ESCC） and analyze its relationship with clinicopathological features. METHODS： RT-PCR and immunocytochemical staining were used to detect the expression of midkine mRNA and protein in EC109 cells, respectively. Then the expression of midkine in 66 cases of ESCC samples were detected by immunohistochemistry using monoclonal antibodies against human midkine. RESULTS： Midkine was expressed in EC109 cell by RT- PCR and imrnunocytochemistry. The immunoreactivity was detected in 56.1% （37/66） of the ESCC samples. The expression of midkine was found in cytoplasm of tumor cells. Notably, the intensity of midkine was stronger at the area abundant in vessels and the invading border of the tumors. Midkine was more intensely expressed in well differentiated tumors （76.9 %） than in moderately and poorly differentiated tumors （43.1% and 41.2%, respectively）（P〈0.05）. There was no statistically significant correlation between midkine expression and gender, age, clinical stage, lymph node metastasis or survival in ESCC. CONCLUSION： IVlidkine is overexpressed in ESCC. It may play a role in tumor angiogenesis and invasion. The expression of midkine is correlated with tumor cell differentiation in ESCC. The more poorly tumor cells differentiate, the weaker midkine expresses.

关键词： Midkine Esophageal squamous cell carcinoma Expression