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Journal of Hydrodynamics 2023年第1期35卷 125-144页

作者： Jia-qi Chen Zhi-Kui He zhi-yang Hu Hong-bo Shi Xikun Wang Research Center of Fluid Machinery Engineering and Technology Jiangsu UniversityZhenjiang212013China Chongqing Pump Industry Co.Ltd. Chongqing400033China

In order to investigate the characteristics of a vertical axial flow pump under various clearances of flare tube, the bell-shaped inlet and box culvert outlet channels with flare tube are studied numerically and experimentally. Then, the cases of inlet and outlet channels with the least hydraulic loss are selected to form an integral pump system, for which both numerical simulation and experimental investigation are carried out. The numerical results agree well with the experimental data. It is shown that the clearances of the interfaces between different components of the pump system have a significant impact on the internal flow structure, turbulent entropy and hydraulic performance of the inlet and outlet channels. For the cases of normalized bottom clearance less than 0.5 and normalized top clearance larger than 0.4, the internal flow and hydraulic performance indexes of inlet and outlet channels are relatively poor. There also exists a critical clearance in either inlet or outlet channel at which the hydraulic loss reaches the maximum. The results serve as an important reference for the design as well as safe and efficient operation of the vertical axial flow pump system.

关键词： Axial flow pump clearance of flare tube numerical simulation experiment hydrodynamic characteristics

Computing top eigenpairs of Hermitizable matrix

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Frontiers of Mathematics in China 2021年第2期16卷 345-379页

作者： Mu-Fa CHEN zhi-Gang JIA Hong-kui PANG Research Institute of Mathematical Science Jiangsu Normal UniversityXuzhou 221116China School of Mathematical Sciences Beijing Normal UniversityBeijing 100875China Laboratory of Mathematics and Complex Systems(Beijing Normal University) Ministry of EducationBeijing 100875China School of Mathematics and Statistics Jiangsu Normal UniversityXuzhou 221116China

The top eigenpairs at the title mean the maximal, the submaximal, or a few of the subsequent eigenpairs of an Hermitizable matrix. Restricting on top ones is to handle with the matrices having large scale, for which only little is known up to now. This is different from some mature algorithms, that are clearly limited only to medium-sized matrix for calculating full spectrum. It is hoped that a combination of this paper with the earlier works, to be seen soon, may provide some effective algorithms for computing the spectrum in practice, especially for matrix mechanics.

关键词： Hermitizable Householder transformation birth-death matrix isospectral matrices top eigenpairs algorithm

Protective effect of telmisartan on rats with renal failure and its mechanism

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Asian Pacific Journal of Tropical Medicine 2015年第6期8卷 497-500页

作者： Zhi-Kui Wang Zhen-Ying Liu Hai-Bo Yu Department of Nephrology Linyi People's Hospital Department of Kidney Disease and Blood Purification Treatment Tianjin Institute of Urology.The Second HospitalTianjin Medical University

Objective:To study the protective effect of telmisartan on rats with renal failure and its mechanism.Methods:60 Wistar rats were chosen as study objective,and were divided into4 groups randomly:15 in group A(sham operation group).15 in group B(model group),15 in group C(telmisartan group) and 15 in group D(telmisartan+GW9962 group).The difference of survival rate,blood-urine biochemical indexes,renal pathological change,and the expression level of PPAR γ and nNOS were ompared.Results:After 12 weeks,the survival rate of group A was 93.33% (14/15),that of group B was 46.67% (7/15),that of group C was86.67% (13/15),that of group D was 60.00% (9/15),and the difference among 4 groups had statistical significance(P0.05);after 3 weeks,6 weeks and 12 weeks,these difference was statistical significant(P<0.05).The difference of blood-urine biochemical indexes,that of renal pathological change,and that of the expression level of PPAR γ and nNOS was statistical significant(P<0.05).Conclusions:Telmisartan has protective effect on renal failure caused by 5/6 nephrectomy,which might be relative to the expression level of PPAR γ and nNOS.

关键词： Telmisartan 5/6 nephrectomy Renal failure

Variation of Two-photon Absorption Cross Sections and Optical Limiting of Compounds Induced by Static Electric Field

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化学物理学报（英文） 2014年第3期27卷 259-264页

作者： Yu-jin Zhang Yu-zhi Song Chuan-kui Wang College of Physics and Electronics Shandong Normal University Jinan 250014 China

由数字地用一个反复的预言者修正者解决 Maxwell-Bloch 方程有限差别的时间域技术，我们调查在 4,4 二度(di-n-butylamino ) 宣传很少周期激光脉搏的性质芪(BDBAS ) 分子的媒介当一个静态的电场存在时。动态二光子的吸收(TPA ) 十字节... 详细信息

由数字地用一个反复的预言者修正者解决 Maxwell-Bloch 方程有限差别的时间域技术，我们调查在 4,4 二度(di-n-butylamino ) 宣传很少周期激光脉搏的性质芪(BDBAS ) 分子的媒介当一个静态的电场存在时。动态二光子的吸收(TPA ) 十字节被获得并且光限制(OL ) 行为被显示。结果证明当静态的电场紧张增加时，动态 TPA 生气的节被提高， OL 行为被改进。而且，平顺序、奇怪顺序的泛音光谱因为它打破 BDBAS 分子的倒置对称，部件与静态的电场的存在被产生。这个工作提供一个方法调制 BDBAS 混合物的非线性的光性质。

关键词：双光子吸收截面静电场化合物光限幅有限差分时域法非线性光学性质诱导布洛赫方程

Geology and mineralization of the supergiant Shimensi granitic-type W-Cu-Mo deposit(1.168 Mt)in northern Jiangxi,South China:A Review

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China Geology 2022年第3期5卷 510-527页

作者： zhi-hui Zhang Da Zhang Xin-kui Xiang Xin-you Zhu Xiao-long He Development and Research Center of China Geological Survey Ministry of Natural ResourcesBeijing 100037China China University of Geosciences Beijing 100083China Geological team 916 of Jiangxi Geology&Mineral Exploration Bureau Jiujiang 332100China Beijing institute of Geology and Mineral Resources Beijing 100012China College of Environment and Resources Xiangtan UniversityXiangtan 411105China

The Shimensi deposit is a recently discovered W-Cu-Mo polymetallic deposit located in the Jiangnan porphyry-skarn W belt in South China.The deposit has a resource of 0.74×10^(6)t of WO_(3)accompanied by 0.4×10^(6)t Cu and 28000 t Mo and other useful components like Ga,making it one of the largest W deposits in the world.This paper is aimed to reveal the ore-controlling mechanisms of the Shimensi deposit,involving the role of the ore-related granites,the tectonic background for its formation,and the metallogenesis model.The systematic geological survey suggests multi-types of alteration are developed in the deposit,mainly including greisenization,potassic-alteration,sericitization,chloritization,and silicification.Drilling engineering data and mining works indicate that the Shimensi deposit consists of two main orebodies of I and II.Therein,the W resource has reached a supergiant scale,and the accompanied Cu,Mo,Au,Bi,Ga,and some other useful components are also of economic significance.The main ore-minerals consist of scheelite,wolframite and chalcopyrite.Disseminated mineralization is the dominant type of the W-Cu-Mo polymetallic orebodies,and mainly distributes in the inner and external contact zone that between the Neoproterozoic biotite granodiorite and the Yanshanian granites.The main orebody occurs at the external contact zone,and the pegmatoid crust near the inner contact zone is an important prospecting marker of the W mineralization.Of them,the disseminated W ores within the wall rock of the Neoproterozoic biotite granodiorite is a new mineralization type identified in this paper.Combining previous geochronological and isotopic data,we propose that the mineralization of the Shimensi deposit is closely related to the intruding of the Yanshanian porphyritic biotite granite and granite porphyry.Geochemical data suggest that the biotite granodiorite is rich in Ca and had provided a large amount of Ca for the precipitation of scheelite in this area.Thus,it is a favorable wall rock type for W mineralization.The

关键词： Tungsten deposit Granitic-type deposit Metallogenesis Lower Yangtze metallogenic belt Porphyry-skarn W belt Mineral exploration engineering Shimensi Dahutang ore field South China

Dispersal routes of Cercospora zeina causing maize gray leaf spot in China

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Journal of Integrative Agriculture 2022年第10期21卷 2943-2956页

作者： DUAN Can-xing ZHAO Li-ping WANG Jie LIU Qing-kui YANG zhi-huan WANG Xiao-ming Institute of Crop Sciences Chinese Academy of Agricultural Sciences/National Key Facility for Crop Gene Resources and Genetic ImprovementBeijing 100081P.R.China Department of Biological Center Harbin Academy of Agricultural SciencesHarbin 150028P.R.China

The gray leaf spot caused by Cercospora zeina has become a serious disease in maize in China.The isolates of C.zeina from Yunnan,Sichuan,Guizhou,Hubei,Chongqing,Gansu,and Shaanxi were collected.From those,127 samples were used for genetic diversity analysis based on inter-simple sequence repeat(ISSR)and 108 samples were used for multi-gene sequence analysis based on five gene fragments.The results indicated that populations of C.zeina were differentiated with a relatively high genetic level and were classified into two major groups and seven subgroups.The intra-population genetic differentiation of C.zeina is the leading cause of population variation in China,and interpopulation genetic similarity is closely related to the colonization time and spread direction.The multi-gene sequence analysis of C.zeina isolates demonstrated that there were nine haplotypes.Genetic diversity and multi-gene sequence revealed that Yunnan population of C.zeina,the earliest colonizing in China,had the highest genetic and haplotype diversity and had experienced an expansion event.With the influence of the southwest monsoon in the Indian Ocean,C.zeina from Yunnan gradually moved to Sichuan,Guizhou,Shaanxi,Gansu,and Chongqing.Meanwhile,C.zeina was transferred directly from the Yunnan into the Hubei Province via seed and then came into Shaanxi,Henan,and Chongqing along with the wind from Hubei.

关键词： maize gray leaf spot Cercospora zeina population disperse routes

Experimental investigation of liquid water in flow field of proton exchange membrane fuel cell by combining X-ray with EIS technologies

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Science China(Technological Sciences) 2021年第10期64卷 2153-2165页

作者： TONGSH Chasen LIANG YiQi XIE Xu LI LinCai LIU zhi DU Qing JIAO kui State Key Laboratory of Engines Tianjin UniversityTianjin 300350China

The flow field is a pivotal part to manage the transport of water and gas in proton exchange membrane fuel cell.However,the reported water measurement methods(e.g.,X-ray and electrochemical impedance spectroscopy(EIS))cannot give a comprehensive understanding water distribution in the flow field,resulting in challenges in optimizing the channel design and enhancing fuel cell performance.Therefore,we propose a water measurement method combining the X-ray radiography with EIS to investigate the effect of different operating conditions on the growth law and distribution of liquid water in parallel and serpentine flow fields.The attenuation coefficient of liquid water to X-ray is calibrated with constant tube-current and tubevoltage of X-ray generator.Besides,the parallel flow field with hydrophobic treatment is studied.The results show that the water accumulation of the parallel flow field is far more than the serpentine flow field,and the water content of the middle region is higher than that of other regions in the parallel flow field.Furthermore,operating conditions(cathode inlet gas flow rate,inlet gas humidity,and back pressure)have little effect on the liquid water content of the middle region in the parallel flow field.The polarization curve,EIS result,and X-ray radiography show that the performance and water drainage capacity of the hydrophobic parallel flow field are better than the normal one.

关键词： proton exchange membrane fuel cell water management flow field X-ray EIS

Neural stem cell-derived exosome as a nano-sized carrier for BDNF delivery to a rat model of ischemic stroke

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Neural Regeneration Research 2023年第2期18卷 404-409页

作者： zhi-Han Zhu Feng Jia Waqas Ahmed Gui-Long Zhang Hong Wang Chao-Qun Lin Wang-Hao Chen Lu-kui Chen Department of Neurosurgery School of MedicineSoutheast UniversityNanjingJiangsu ProvinceChina Department of Neurosurgery Neuroscience CenterCancer CenterIntegrated Hospital of Traditional Chinese MedicineSouthern Medical UniversityGuangzhouGuangdong ProvinceChina Department of Neurosurgery The Second Affiliated Hospital of Guangzhou Medical UniversityGuangzhouGuangdong ProvinceChina Department of Neurosurgery Shanghai Ninth People’s HospitalShanghai Jiao Tong University School of MedicineShanghaiChina

Our previo us study demonstrated the potential therapeutic role of human neural stem cell-derived exosomes(hNSC-Exo)in ischemic stroke.Here,we loaded brain-derived neurotrophic factor(BDNF)into exosomes derived from NSCs to construct engineered exosomes(BDNF-hNSC-Exo)and compared their effects with those of hNSC-Exo on ischemic stroke both in vitro and in vivo.In a model of H_(2)O_(2)-induced oxidative stress in NSCs,BDNF-hNSC-Exo markedly enhanced cell survival.In a rat middle cerebral arte ry occlusion model,BDNF-hNSC-Exo not only inhibited the activation of microglia,but also promoted the differentiation of endogenous NSCs into neurons.These results suggest that BDNF can improve the function of NSC-derived exosomes in the treatment of ischemic stro ke.Our research may support the clinical use of other neurotrophic factors for central nervous system diseases.

关键词： brain-derived neurotrophic factor exosome inflammation ischemic stroke neural stem cell neurogenesis neurological recovery transplantation

Aligned single-walled carbon nanotubes array electrode:Fabrication,characterization and application

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Chinese Chemical Letters 2009年第1期20卷 76-78页

作者： Xu zhi Zhang kui Jiao College of Chemistry and Molecular Engineering Qingdao University of Science and Technology Qingdao 266042 China

In the presence of 1-（3-dimethylaminopropyl）-3-ethylcarbodiimide hydrochloride （EDC） and N-hydroxysuccinimide （NHS）, carboxylic group-functionalized single-walled carbon nanotubes （SWNTs） were assembled vertically on the glassy carbon electrode using ethylenediamine as linking agent to fabricate an aligned electrode （SWNTE）. The morphological characteristic was studied with atomic force microscope （AFM） and its electrochemical property was investigated using K3[Fe（CN）6] as probe. ssDNA had a sensitive voltammetric response at the SWNTE and the oxidative peak potentials of guanine base and adenine base were 0.608 Vand 0.896 V, respectively. Under the optimal conditions, the DPV peak current of guanine base vs. the concentration of ssDNA was linear in the range of 5.4 μg/L-10.8 mg/L with a detection limit of 1 μg/L （S/N = 3）.

关键词： Single-walled carbon nanotubes Aligned electrode DNA Voltarnmetry

Kinetic triplet from low-temperature carburization and carbon deposition reactions

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Journal of Iron and Steel Research(International) 2022年第10期29卷 1545-1558页

作者： Wei Zhang kui Li Jian-hong Dong Cheng-zhi Li Ai-hua Liu Ju-hua Zhang Zheng-liang Xue The State Key Laboratory of Refractories and Metallurgy Wuhan University of Science and TechnologyWuhan430081HubeiChina Key Laboratory for Ferrous Metallurgy and Resources Utilization of Ministry of Education Wuhan University of Science and TechnologyWuhan430081HubeiChina Hanshan Normal University Chaozhou521041GuangdongChina Key Laboratory of Ecological Utilization of Multi-Metallic Mineral of Education Ministry Northeastern UniversityShenyang110819LiaoningChina

Carbon deposition reaction is unfavorable for smooth operation of blast furnace,while the product of carburization reaction is a superior iron-bearing raw material in non-blast furnace routes.The kinetic triplet of these two reactions was obtained based on non-isothermal kinetic analysis.According to the Sharp–Wentworth method,the activation energy of the carburization reaction is 397.77 kJ/mol,and the activation energies of the carbon depositions on hematite and magnetite are 188.92 and 100.89 kJ/mol,respectively.The carburization reaction is controlled by the Jander mechanism,and the carbon depositions on hematite and magnetite are both controlled by the mechanism of Zhuravlev–Lesokhin–Tempelman.Based on Coats–Redfern method,the activation energies of the above three reactions are 360.65,149.29,and 102.36 kJ/mol,respectively.The carburization reaction is a first-order reaction,while the carbon depositions on hematite and magnetite are both third-order reaction.In particular,the negative activation energy is obtained if considering the anti-Arrhenius circumstance in the Sharp-Wentworth method.Based on above results,it is feasible to adopt non-isothermal kinetic method to study the kinetic triplet of a reaction.According to the obtained activation energies and reaction mechanism functions,the simulated kinetic data are in good agreement with the experimental values even using the negative activation energy.

关键词： Kinetic triplet Carburization reaction Carbon deposition Non-isothermal kinetic Magnetite Hematite