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Journal of Central South University 2000年第4期12卷 201-204页

作者： CHEN Zhen-hua KANG zhi-tao YAN Hong-ge Department of Materials Science and Engineering Central South UniversityChangsha 410083China

Principle of multilayer spray forming and preparation technique of tubes and billets by it were presented and described in the article. The marked characteristic of multilayer spray forming technology is the to and fro movement of spray system, so the preform is deposited layer by layer with the surface of the deposit retaining relatively low temperature during the spray forming process. The two outstanding advantages of multilayer spray forming are as follows: suitable for manufacturing large dimension blanks, higher solidification cooling rate. Now Al Fe V Si alloy (8009) and SiC particle reinforced aluminium alloy metal matrix composite billets of 300 600 mm in diameter and tubular blanks of size up to 650 mm in outer diameter, 360 mm in inner diameter and 1 200 mm in length have been made with the technology. After extrusion, the material has good properties.

关键词： multilayer spray forming billet tube aluminium alloy composite

Effect of Graphite Content and Granularity on Mechanical and Tribological Properties of Bronze Alloyed Powder Composite

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Journal of Iron and Steel Research International 2005年第1期12卷 54-57页

作者： DENG Chen-hong CHEN Guang-zhi ge Qi-lu Central Iron and Steel Research Institute

The bronze alloyed powder composite containing nanoparticles was developed by hot *** effects of the content and granularity of graphite on hardness,machinability,bending strength,compression strength,and friction and wear behavior of the composites were *** microstructures of the specimens were analyzed by *** results showed that the graphites are distributed in net when nanographites are added,resulting in the decrease of mechanical properties and abrasive *** the content of nanographite is 10%,the composite is *** graphite is distributed in the form of block when micrographite is added,improving the mechanical properties and abrasive *** track was studied by SEM.

关键词： nanoparticle mechanical property friction wear abrasive resistance

A new method for fluid identification and saturation calculation of low contrast tight sandstone reservoir

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Petroleum Science 2024年第5期21卷 3189-3201页

作者： shuai Wang Ran-Hong Xie Guo-Wen Jin Jiang-Feng Guo Li-zhi Xiao State Key Laboratory of Petroleum Resources and Engineering China University of Petroleum(Beijing)Beijing102249China

The resistivity difference between oil and gas layers and the water layers in low contrast tight sandstone reservoirs is subtle. Fluid identification and saturation calculation based on conventional logging methods are facing challenges in such reservoirs. In this paper, a new method is proposed for fluid identification and saturation calculation in low contrast tight sandstone reservoirs. First, a model for calculating apparent formation water resistivity is constructed, which takes into account the influence of shale on the resistivity calculation and avoids apparent formation water resistivity abnormal *** on the distribution of the apparent formation water resistivity obtained by the new model, the water spectrum is determined for fluid identification in low contrast tight sandstone *** this, according to the average, standard deviation, and endpoints of the water spectrum, a new four-parameter model for calculating reservoir oil and gas saturation is built. The methods proposed in this paper are applied to the low contrast tight sandstone reservoirs in the Q4 formation of the X53 block and X70 block in the south of Songliao Basin, China. The results show that the water spectrum method can effectively distinguish oil-water layers and water layers in the study area. The standard deviation of the water spectrum in the oil-water layer is generally greater than that in the water layer. The new four-parameter model yields more accurate oil and gas saturation. These findings verify the effectiveness of the proposed methods.

关键词： Low contrast reservoirs Fluid identification Saturation calculation Water spectrum method Conventional logging

Diversity of bacteria in different life stages and their impact on the development and reproduction of Zeugodacus tau(Diptera:Tephritidae)

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Insect Science 2021年第2期28卷 363-376页

作者： MdShibly Noman ge Shi Li-Jun Liu zhi-Hong Li Department of Entomology MOA Key Lab of Pest Monitoring and Green ManagementCollege of Plant ProtectionChina Agricultural UniversityBeijingChina

Fruit flies usually harbor diverse communities of bacteria in their digestive systems,which are known to play a significant role in their ***,little information is available on Zeugodacus tau,a polyphagous pest *** study reports the first extensive analysis of bacterial communities in different life stages and their effect on the development and reproduction of laboratory-reared Z *** bacteria were identified using the conventional method and all bacteria were identified by highthroughput technologies(16S ribosomal RNA gene sequencing of V3-V4 region).A total of six bacterial phyla were identified in larvae,pupae,and male and female adult flies,which were distributed into 14 classes,32 orders,58 families and 96 *** was the most represented phylum in all the stages except ***,Klebsiella,Providencia,and Pseudomonas were identified by conventional and next-generation sequencing analysis in both male and female adult flies,and Enterobacter was found to be the main *** being fed with antibiotics from the first instar larvae,bacterial diversity changed markedly in the adult *** flies laid eggs and needed 20 days before oviposition while the treated flies showed ovary development inhibited and were not able to lay eggs,probably due to the alteration of the *** findings provide the cornerstone for unexplored research on bacterial function in Z tau,which will help to develop an environmentally friendly management technique for this kind of harmful insect.

关键词： antibiotics bacterial diversity fitness oviposition symbiotic bacteria Zeugodacus tau

Effects of the number of imidazoline ring and the length of alkyl group chain of imidazoline derivatives on corrosion inhibition of carbon steel in HCl solution:Molecular simulation and experimental validation

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Petroleum 2022年第4期8卷 447-457页

作者： Chenfeng Zhang Junying Hu zhi Yang Ziqi Zheng shuai geng Xiankang Zhong School of Oil and Natural Gas Engineering Southwest Petroleum UniversityChengdu610500China School of Materials Science and Engineering Xihua UniversityChengdu610039China State Key Laboratory of Oil and Gas Reservoir geology and Exploitation Southwest Petroleum UniversityChengdu610500China

The effects of the number of imidazoline ring and the length of alkyl group chain of imidazoline derivatives were investigated using quantum chemical calculation,molecular dynamics simulation and experimental *** corrosion inhibitors including symmetrical lauric acid imidazoline(SAI),tetracyclic lauric acid imidazoline(LAI),and symmetric stearic acid imidazoline(SPI)were synthesized and their inhibition performance was evaluated using weight loss measurement,electrochemical techniques and surface *** results show that SAI and LAI with the same length of alkyl group chain,LAI with more imidazoline rings could supply a better inhibition performance since the increase of active *** increase of active sites attached to the metal surface may also change the distribution of corrosion inhibitor,which could limit inhibition performance ***,SAI and SPI with the same number of imidazoline rings,SPI with longer alkyl group chain shows a better inhibition efficiency due to the better hydrophobic performance of alkyl *** the three inhibitors,SPI shows the best inhibition performance,indicating that the alkyl group chain length affects the inhibition performance more obvious than the number of the imidazoline rings.

关键词： Imidazoline derivatives Corrosion inhibition Imidazoline ring Alkyl group chain

geometry effect in reactive shock-elliptic bubble interactions

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Acta Mechanica Sinica 2021年第11期37卷 1624-1636,I0001页

作者： Dong-Dong Li ge Wang Bin Zhang zhi-Bang Wang Ben Guan School of Aeronautics and Astronautics Shanghai Jiao Tong UniversityShanghai200240China College of Aerospace and Civil Engineering Harbin Engineering UniversityHarbin150001China

The shock-induced ignition and detonation wave propagation in reactive elliptic premixed bubbles are numerically *** attention is paid to the bubble geometry effect on the ignition pattern and the ensuing bubble *** elliptic bubbles with different aspect ratios are *** to the numerical results,three typical ignition patterns are identified under the same incident shock strength and the underlying mechanisms are *** difference in ignition pattern shows that,comparing with the inert shock-bubble interaction,the geometry effect in reactive shock-bubble interaction(RSBI)has more *** addition to the aspect ratio,the ignition location and the distance from the ignition spot to the nearest/farthest bubble surface should also be considered as elements of the geometry effect in RSBI.

关键词： Reactive shock-bubble interaction Shock wave ignition Elliptic bubble geometry effect Numerical simulation

Study on Rigid-Flexible Coupling Effects of Floating Offshore Wind Turbines

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China Ocean Engineering 2019年第1期33卷 1-13页

作者： CHEN Jia-hao HU zhi-qiang LIU ge-liang WAN De-cheng State Key Laboratory of Ocean Engineering Shanghai Jiao Tong University Collaborative Innovation Center for Advanced Ship and Deep-Sea Exploration Shanghai Jiao Tong University School of Engineering Newcastle University

In order to account for rigid-flexible coupling effects of floating offshore wind turbines, a nonlinear rigid-flexible coupled dynamic model is proposed in this paper. The proposed nonlinear coupled model takes the higher-order axial displacements into account, which are usually neglected in the conventional linear dynamic model. Subsequently,investigations on the dynamic differences between the proposed nonlinear dynamic model and the linear one are conducted. The results demonstrate that the stiffness of the turbine blades in the proposed nonlinear dynamic model increases with larger overall motions but that in the linear dynamic model declines with larger overall *** of the blades in the nonlinear dynamic model is more reasonable than that in the linear model as ***, more distinct coupling effects are observed in the proposed nonlinear model than those in the linear model. Finally, it shows that the aerodynamic loads, the structural loads and global dynamic responses of floating offshore wind turbines using the nonlinear dynamic model are slightly smaller than those using the linear dynamic model. In summary, compared with the conventional linear dynamic model, the proposed nonlinear coupling dynamic model is a higher-order dynamic model in consideration of the rigid-flexible coupling effects of floating offshore wind turbines, and accord more perfectly with the engineering facts.

关键词： floating offshore wind turbine dynamic stiffening effect nonlinear coupled dynamic model DARwind

Effect of Heat Treatment Process on Mechanical Properties and Microstructure of Modified CNS-ⅡF/M Steel

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Journal of Iron and Steel Research International 2011年第12期18卷 65-70页

作者： YANG Ying YAN Qing-zhi MA Rong ge Chang-chun School of Materials Science and Engineering University of Science and Technology Beijing Beijing 100083 China

Ferritic/martensitic（F/M） steels have been recommended as one of the candidate materials for supercritical water cooled reactor（SCWR） in-core components use for its high thermal conductivity,low thermal expansion coefficient and inherently good dimensional stability under irradiation condition in comparison to austenitic ***-Ⅱ F/M steel which has good mechanical properties was one of the 9-12Cr F/M steels designed for SCWR in the previous *** this study a modified CNS-Ⅱ F/M steel was used and it＇s ultimate tensile strength was 925 MPa at room temperature and 483 MPa at 600 ℃ after optimizing heat treatment *** ductile to brittle transition temperature of modified CNS-Ⅱ F/M steel is-55 ℃.Those are at the same level or even higher than that of CNS-Ⅱ and some commercial F/M steels nominated for SCWR in-core component *** transmission electron microscope（TEM） results showed that the mechanical properties of the tempered martensite was closely related to the decomposition stage of the martensite.

关键词： supercritical water reactor ferritic/martensitic steel cladding material

Immobilization and Properties of Lipase from Candida rugosa on Electrospun Nanofibrous Membranes with Biomimetic Phospholipid Moities

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Chemical Research in Chinese Universities 2008年第2期24卷 231-237页

作者： HUANG Xiao-jun YU An-guo ge Dan XU zhi-kang Institute of Polymer Science Key Laboratory of Macromolecular Synthesis and Functionalization of Ministry of Education State Key Laboratory of Chemical Engineering Zhejiang University Hangzhou 310027 P. R. China

Reported here is a protocol to fabricate a biocatalyst with high enzyme loading and activity retention, from the conjugation of electrospun nanofibrous membrane having biomimetic phospholipid moiety and lipase. To improve the catalytic efficiency and activity of the immobilized enzyme, poly（acrylonitrile-co-2-methacryloyloxyethyl phosphorylcholine）s（PANCMPCs） were, respectively, electrospun into nanofibrous membranes with a mean diameter of 90 nm, as a support for enzyme immobilization. Lipase from Candida rugosa was immobilized on these nanofibrous membranes by adsorption. Properties of immobilized lipase on PANCMPC nanofibrous membranes were compared with those of the lipase immobilized on the polyacrylonitrile（PAN） nanofibrous and sheet membranes, respectively. Effective enzyme loading on the nanofibrous membranes was achieved up to 22.0 mg/g, which was over 10 times that on the sheet membrane. The activity retention of immobilized lipase increased from 56.4% to 76.8% with an increase in phospholipid moiety from 0 to 9.6%（molar fraction） in the nanofibrous membrane. Kinetic parameter Km was also determined for free and immobilized lipase. The Km value of the immobilized lipase on the nanofibrous membrane was obviously lower than that on the sheet membrane. The optimum pH was 7.7 for free lipase, but shifted to 8.3-8.5 for immobilized lipases. The optimum temperature was determined to be 35 ℃ for the free enzyme, but 42-44℃ for the immobilized ones, respectively. In addition, the thermal stability, reusability, and storage stability of the immobilized lipase were obviously improved compared to the free one.

关键词： Biomimetic polymer Nanofibrous membrane Electrospinning Enzyme immobilization Lipase

Experimental study on a cryosurgery apparatus

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2010年第2期11卷 128-131页

作者： Shao-zhi ZHANG Dong-bo WU ge YANG Guang-ming CHEN Institute of Refrigeration and Cryogenics Zhejiang University Hangzhou 310027 China

Cryosurgery is an effective way of curing many diseases including tumors and cancers. It can be applied using a variety of systems and cryogens. Cheap, convenient, reliable equipment still needs to be developed so that cryotherapy may be accepted by surgeons and hospitals. This paper presents a cryosurgery apparatus that utilizes an auto-cascade refrigeration system. Refrigerant mixture R50/R23/R600a was selected as the working fluid. The mixture composition was altered to achieve lower temperatures and higher capacity. The lowest temperature at the cryoprobe could be as low as -100℃, and 8 W refrigeration capacity could be obtained at -80 ℃. An ice ball of 11.6 mm diameter could be formed when the cryoprobe was immersed in a water bath at 37 ℃.

关键词： Cryosurgery Cryoprobe Auto-cascade refrigeration system Refrigerant mixture