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Dynamic Simulating to the Accumulation and Distribution of Dry Matter for Black Walnut(Juglans hindsii) Seedlings

Agricultural Sciences in China 2010年第1期9卷 56-63页

作者： ZHANG Ji-xiang MAO Zhi-quan SHU huai-rui WEI Qin-ping State Key Laboratory of Crop Biology College of Horticultural Science and Engineering Shandong Agricultural University Tai＇an 271018 P.R.China Institute of Forestry ＆ Pomology Beijing Academy of Agriculture ＆ Forestry Sciences Beijing 100093 P.R.China

It is very important to study eco-physiological processes of plants and to determine quantitative relations between accumulation, distribution of dry matter and environmental factors for regionalization, standardization and precision agriculture. Meanwhile, global changes, e.g., atmospheric CO2 concentration rising, global warming, and climate abnormity, have been effecting on agricultural productivity. This study provides a theoretical basis for predicting productive potentials and development trends in different agricultural regions. One-year-old black walnut （Juglans hindsii） seedlings were employed as subjects for setting up the dynamic models of dry matter accumulation and distribution, based on mechanistic models of photosynthesis, matter conservation and concentration gradient. Under optimum conditions of soil moisture and mineral nutrient, during the period of the canopy construction, the dry matter accumulation of the canopy conformed to logistic curves; but the accumulation of both total biornass and dry matter of stem-root could be divided into two phases： the first phase was exponential increase, the second was linear increase. The total biomass, dry matter of canopy and stem-root all presented a fluctuant increase, which was affected by the environmental factors. Ratio of daily increase of dry matter in the canopy and the steem-root （dWJdWs） was changeable along with growth periods and environmental factors. At the initial stage of the canopy forming, dW/dWs was larger, about 3.2 on average, which indicated that the photosynthetic product was mainly used to develop leaves; in the midterm, it was about 1.9, which indicated that the distribution of dry matter in the canopy and in the stem-root was relatively balanced; when the plant tended to stop growing, dWl/dWs decreased linearly, and the main distribution of dry matter moved to the roots.

关键词： black walnut dry matter accumulation and distribution dynamic model

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Current Strategies of Surface Modifications to Polyurethane Biomaterials for Vascular Grafts

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Chinese Medical Sciences Journal 2023年第4期38卷 279-285页

作者： huai-Gu Huang Tao xiang Yue-Xin Chen Department of Vascular Surgery Peking Union Medical College HospitalChinese Academy of Medical Sciences&Peking Union Medical CollegeBeijing 100730China Department of Burns and Plastic Surgery Affiliated Hospital of Zunyi Medical UniversityZunyiGuizhou 563000China

As the number of patients suffering from cardiovascular diseases and peripheral vascular diseases rises,the constraints of autologous transplantation remain *** a result,artificial vascular grafts must be *** of proteins,platelets and bacteria on implants can result in stenosis,thrombus formation,and postoperative infection,which can be fatal for an ***,as a commonly used biomaterial,has been modified in various ways to deal with the adhesions of proteins,platelets,and bacteria and to stimulate endothelium *** this review,we briefly summarize the mechanisms behind adhesions,overview the current strategies of surface modifications of polyurethane biomaterials used in vascular grafts,and highlight the challenges that need to be addressed in future studies,aiming to gain a more profound understanding of how to develop artificial polyurethane vascular grafts with an enhanced implantation success rate and reduced side effect.

关键词： surface modification polyurethane vascular graft adhesion

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Study on Contact Algorithm of Dynamic Explicit FEM for Sheet Forming Simulation

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Wuhan University Journal of Natural Sciences 2001年第3期6卷 704-708页

作者： Zhang Hai-ming Dong xiang-huai Li Zhi-gang State Key Laboratory of PFSDMT Huazhong Univ. of Sci./Technology Wuhan 430074 China

Based on existing algorithms, a newly developed contact search algorithm is proposed. The new algorithm consists of global search, local searching, local tracking and penetration calculation processes. It requires no iteration steps. It can deal with not only general tool surfaces with vertical walls, but also tool surfaces meshed with elements having very poor aspect ratios. It is demonstrated that the FE code employing this new contact search algorithm becomes more reliable, efficient and accurate for sheet metal forming simulation than conventional ones.

关键词： contact algorithm dynamic explicit FEM sheet metal forming

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Influence of Ce and Mn addition on α-Fe morphology in recycled Al-Si alloy ingots

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International Journal of Minerals,Metallurgy and Materials 2013年第9期20卷 890-895页

作者： Chao Fan Si-yuan Long huai-de Yang xiang-jie Wang Jun-cheng Zhang College of Materials Science and Engineering Chongqing University Engineering Training Center Guangxi University of Science and Technology

The influence of Ce or Ce and Mn combined additions on the morphology of a-Fe phases in recycled AloSi alloys was experimentally investigated by microstructure observation and room temperature tensile testing. It is found that Ce modifies the morphology of a-Fe phase from the large Chinese script-like into the individual and fine nodular shape. A combined addition of Ce and Mn results in the promotion of primary a-Fe formation, and their size increases considerably with the increase in Ce content. The mechanism of the above morphological changes was discussed in accordance with the nucleation and growth of a-Fe phase during solidification.

关键词： aluminum-silicon alloys cerium manganese modification morphology

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Synthesis and cytotoxic activities of E-resveratrol derivatives

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Chinese Journal of Natural Medicines 2015年第5期13卷 375-382页

作者： HONG Ting JIANG Wei DONG huai-Ming QIU Sheng-xiang LU Yu Sino-German Joint Research Institute of Nanchang University Jiangxi Provincial Institute for Food and Drug Control Jiangxi Provincial Engineering Research Center for Drug and Medical Device Quality Chinese Academy of Sciences South China Botanical Garden

The present study was designed to synthesize derivatives of E-resveratrol and evaluate their cytotoxic activity in *** functional groups were conjugated with the phenolic hydroxyl group of E-resveratrol,and the double bond of E-resveratrol was *** in vitro cytotoxicity of the synthetic derivatives was evaluated against three tumor cell lines(A549,LAC,and He La) using the MTT ***-six E-resveratrol derivatives were synthesized and their structures were confirmed by 1H NMR,MS,IR,and elemental *** 1-6,12,15-21,and 23-26 were reported for the first *** them,Compounds 1,2,4,5,and 9-11,showed significant cytotoxicity against tumor cells;especially,Compound 1 showed an IC50 value of 4.38 μmol·L-1 in the A549 cells which was 15-fold more active than E-resveratrol;Compound 9 showed an IC50 value of 1.41 μmol·L-1 in the He La cell line which was 90-fold more active than E-resveratrol,and close to *** structure–activity relationships were also *** 1,2 and 9-11 may serve as potential lead compounds for the discovery of new anticancer drugs.

关键词： E-resveratrol derivatives Synthesis Cytotoxic activity Structure–activity relationships

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Resource Reconstruction Algorithms for On-demand Allocation in Virtual Computing Resource Pool

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International Journal of Automation and computing 2012年第2期9卷 142-154页

作者： Xiao-Jun Chen Jing Zhang Jun-huai Li xiang Li School of Computer Science and Engineering Xi＇an University of Technology Xi＇an 710048 PRC State Key Laboratory for Manufacturing Systems Engineering Xi＇an Jiaotong University Xi~an 710048 PRC

Resource reconstruction algorithms are studied in this paper to solve the problem of resource on-demand allocation and improve the efficiency of resource utilization in virtual computing resource pool. Based on the idea of resource virtualization and the analysis of the resource status transition, the resource allocation process and the necessity of resource reconstruction are presented, l^esource reconstruction algorithms are designed to determine the resource reconstruction types, and it is shown that they can achieve the goal of resource on-demand allocation through three methodologies： resource combination, resource split, and resource random adjustment. The effects that the resource users have on the resource reconstruction results, the deviation between resources and requirements, and the uniformity of resource distribution are studied by three experiments. The experiments show that resource reconstruction has a close relationship with resource requirements, but it is not the same with current distribution of resources. The algorithms can complete the resource adjustment with a lower cost and form the logic resources to match the demands of resource users easily.

关键词： Virtual computing systems virtual computing resource pool resource allocation resource reconstruction status tran-sition resource combination resource split resource adjustment.

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Experimental study on evolution of bed structures of natural mountain rivers

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Water Science and Engineering 2011年第2期4卷 192-203页

作者： huai-xiang LIU Zhao-yin WANG Guo-an YU Kang ZHANG State Key Laboratory of Hydrology-Water Resources and Hydraulic Engineering Nanjing Hydraulic Research Institute Nanjing 210029 P. R. China State Key Laboratory of Hydroscience and Engineering Tsinghua University Beijing 100084 P. R. China

Bed structures in many mountain rivers provide additional resistance to the flow. A field experiment was conducted on debris flow deposits in the valley of the Jiangjiagou Ravine, a tributary of the Yangtze River in southwestern China, to study the evolution and distribution of bed structures and their relationship with environmental conditions. Water and sediment from the Jiangjiagou main stream were diverted into the experimental channel. Several hydrological schemes were adopted to scour the channel until equilibrium was reached. During this process the evolutions of bed structures and channel configuration were investigated. The results indicate that stronger bed structures mean greater stream power consumption, greater resistance, and greater slope in a certain section when rivers are in dynamic equilibrium. Thus, to some extent the longitudinal profiles of channels can be determined by the distribution of bed structures. In natural cases, the strength and evolution of bed structures are under the influence of environmental conditions such as discharge and bed-load transportation rate. That is, given the same conditions, the same bed structure distribution and longitudinal profile can be predicted.

关键词： bed structures channel configuration channel incision slope resistance

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Protection effect of Emodin pretreatment on intestinal I-RI damage of intestinal mucosa in ratsa

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Asian Pacific Journal of Tropical Medicine 2014年第9期7卷 749-753页

作者： Shu-Jie Zhao Shi-Ji Wang Hong-xiang Li Li-Hua Dong huai-Jiang He zhong-Min Liu Yu-Shan Wang ICU First Hospital of Jilin University

Objective:To linvestigate the protective effect and mechanism of emodin pretreatment on intestinal mucosa of rats with intestinal ischemia-reperfusion ***:A total of 50SD rats were randomly divided into control group,model group,emodin groups of low,medium and high dose,with 10 in each ***-reperfusion injury(I-RI)mode was established by using noninvasive clamp on superior mesentericartery(SMA).Control group and model group were pretreated with 0.5%sodium carboxymethyl cellulose solution lavage 2 h before operation,emodin groups of low,medium and high dose were given emodin lavage with 20,40,60 mg/kg pretreatment,femoral venous blood before the lavage pretreatment(TO)and 1 h ischemia(Tl),and inferior vena venous blood after 1 h of reperfusion(T2)were extracted from each group of rats for detection of serun level of intestinal fatty acid binding protein(I-FABP),tumor necrosis factor(TNF-α),endotoxin,interleukin 6(IL-6),and die content of diamine oxidase(DAO);Mter model establishment,the rats were sacrificed,intestine homogenate was prepared by using blind intestinal tissue to detect intestinal tissue myeloperoxidase(MPO],malondialdehyde(MDA)and superoxide dismutase(SOD)*** upper small intestine tissue was retrieved,followed by fixation and conventional HE staining to observe intestinal tissue morphology under light ***:In emodin groups of low,medium and high dose at T1 and T2,I-FABP,TNF-α,***,-6 and DAO level were significandy lower than that of model group(P<0.05);in emodin group of low,medium and high dose,MPO and MDA content in intestinal tissue homogenate was significantly lower than that in model group(P<0.05),SOD level was significantly higher than that of model group(P<0.05).Intestinal damage of emodin low,medium and high dose groups were significandy lighter than model ***:Emodin pretreatment has certain protective effect on intestinal mucosa in ischemia reperfusion injury.

关键词： Emodin Ischemia-reperfusion injury Intestinal mucosa barrier Protection

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Corrosion Behaviors of Pure Titanium and Its Weldment in Simulated Desulfurized Flue Gas Condensates in Thermal Power Plant Chimney

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Acta Metallurgica Sinica(English Letters) 2015年第4期28卷 477-486页

作者： Zheng-Bing Wang Hong-xiang Hu Chun-Bo Liu huai-Ning Chen Yu-Gui Zheng Key Laboratory of Nuclear Materials and Safety Assessment Institute of Metal ResearchChinese Academy of Sciences Center for Wear and Corrosion Resistant Materials Huadian Zhengzhou Mechanical Design Institute Co.Ltd. Laboratory of Properties and Reliable Joining of Welded Joints Institute of Metal ResearchChinese Academy of Sciences

The corrosion behaviors of pure titanium and its weldment welded by tungsten inert gas （TIG） welding in simulated desulfurized flue gas condensates in thermal power plant chimney were investigated using potentiodynamic polarization, electrochemical impedance spectroscopy （EIS） and immersion tests. The effects of heat input and shielding gases on the corrosion behavior of the welded titanium were also studied. Grain coarsening and Widmanst^itten structure were found in both the fusion zone and the heat-affected zone. The welded titanium exhibited active-passive behavior in the simulated condensates. Both the polarization curves and EIS measurements confirmed that TIG welding process with different parameters had few effects on the corrosion behavior. It was proved that the microstructure changes were not the key material factors affecting the corrosion behavior of pure titanium under the test conditions, while the oxide film had remarkable effect on improving the corrosion resistance.

关键词： Pure titanium Tungsten inert gas welding Simulated desulfurized flue gas condensates Corrosion behavior Microstructure Oxide film

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The Role of Mold Temperature on Morphology and Mechanical Properties of PE Pipe Produced by Rotational Shear

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Chinese Journal of Polymer Science 2020年第6期38卷 653-664页

作者： Zu-Chen Du Hao Yang Xie-huai Luo Ze-xiang Xie Qiang Fu Xue-Qin Gao College of Polymer Science and Engineering Sichuan UniversityChengdu 610065China

The role of mold temperature on the morphology and properties of rotational shearing polyethylene(PE)pipes was studied via a self-.developed rotational shear system(RSS).The result indicated that when the mold temperature was 150℃,the hoop tensile strength and Vicat softening temperature were enhanced rapidly,which were 383.6%and 137.9%higher than those of the conventional PE pipes,*** and crystal structure studies by SEM and DSC revealed that once the rotational shear was applied,the shish-kebab structure began to *** the increase of the mold temperature,due to the relaxation of most of the oriented molecular chains,the preservation of shish-kebab structure became *** the mold temperature was 190℃,only the inner layer of the pipes,where the cooling rate was the largest,could preserve the shish-kebab *** to WAXD,there was less shish structure,and the growth of kebab was distorted in the inner layer of the pipes at 210℃.The result of SAXS suggested that the length of shish changed most within the temperature range from 170℃to 190。*** results of DSC and WAXD showed less change in crystallinity and degree of orientation between the two *** can be concluded that the reduction of shish length leads to a decrease in mechanical properties and heat-resistance.

关键词： Shish-kebab Rotational shear Mold temperature PE pipe

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