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High-Efficiency Second Harmonic Generation of a Pulsed Ti : Al_(2)O_(3) Laser with β-BaB_(2)O_(4) Crysta

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Chinese Physics Letters 1994年第9期11卷 551-553页

作者： LIU Xiang DENG Daoqun zhang Yufei xu Zuyan Institute of Physics Academia SinicaBeijing 100080

Tunable blue radiation with a tuning range of 340-460nm has been generated using aβ-BaB_(2)O_(4) crystal for external frequency doubling of a ns-pulsed Ti:Al_(2)O_(3) *** pumping the Ti:sapphire with 94mJ/pulse of energy from the second harmonic of a Q-switched Nd:YAG laser,as much as 5.4mJ/pulse at 390nm with a bandwidth of 0.02nm was *** represents an infrared to blue conversion efficiency of 36%and a total conversion(from 532nm to blue)of 5.7%.

关键词： Nd:YAG Efficiency tuning

Tribocorrosion behavior of antibacterial Ti-Cu sintered alloys in simulated biological environments

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Rare Metals 2022年第6期41卷 1921-1932页

作者： jia-Qi zhang Shuang Cao Ying Liu Mian-Mian Bao Jing Ren Sheng-Yi Li Er-Lin zhang jian-Jie Wang Departments of Immunology College of Basic MedicineJiamusi UniversityJiamusi 154007China Key Laboratory for Anisotropy and Texture of Materials School of Materials Science and EngineeringEducation Ministry of ChinaNortheastern UniversityShenyang 110819China Research Center for Metallic Wires Northeastern UniversityShenyang 110819China

Ti-Cu alloys have strong antibacterial proper-ties,high strength and excellent corrosion resistance,which might be used in orthopedic and dental *** this paper,the tribocorrosion behaviors of Ti-Cu alloy with different Cu contents were investigated in four simulated biological environments compared with *** results showed that Ti-Cu sintered alloy exhibited higher corro-sion resistance,lower coefficient friction and wear loss than cp-Ti in all tested solutions due to the formation of fine and homogeneously distributed Ti_(2)Cu phase,espe-cially in solution with lower F ion and *** Cu content and extrusion process improved the corrosion resistance and the wear resistance because of high Ti_(2)Cu phase fraction and fine grain ***,aggressive solution,such as the solution with lower F ion and pH,accelerated wear in comparison with other solutions for cp-Ti and Ti-Cu sintered *** electron microscope(SEM)surface morphology demonstrated that the wear mecha-nism of cp-Ti during tribocorrosion process was mainly abrasive wear and adhesive wear while that of Ti-Cu alloy was abrasive *** summary,Ti-Cu sintered alloys showed much better tribocorrosion property than cp-Ti,which shows great potential application in condition for wear and corrosion resistance.

关键词： Ti-Cu alloys Tribocorrosion Corrosion Wear In vitro Antibacterial metal alloy

Experimental investigation of propagation mechanisms and fracture morphology for coalbed methane reservoirs

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Petroleum Science 2018年第4期15卷 815-829页

作者： Chi Ai Xiao-xuan Li Jun zhang Dan jia Wen-Jing Tan College of Petroleum Engineering Northeast Petroleum University College of Geoscience and Technology China University of Petroleum (East China)

Fracture propagation mechanisms in coalbed methane(CBM) reservoirs are very complex due to the development of the internal cleat system. In this paper, the characteristics of initiation and propagation of hydraulic fractures in coal specimens at different angles between the face cleat and the maximum horizontal principal stress were investigated with hydraulic fracturing tests. The results indicate that the interactions between the hydraulic fractures and the cleat system have a major effect on fracture networks. "Step-like’’ fractures were formed in most experiments due to the existence of discontinuous butt cleats. The hydraulic fractures were more likely to divert or propagate along the butt cleat with an increase in the angles and a decrease in the horizontal principal stress difference. An increase in the injection rate and a decrease in the fracturing fluid viscosity were more conducive to fracture networks. In addition, the influence on fracture propagation of the residual coal fines in the wellbore was also studied. The existence of coal fines was an obstacle in fracturing, and no effective connection can be formed between fractures. The experimental investigation revealed the fracture propagation mechanisms and can provide guidance for hydraulic fracturing design of CBM reservoirs.

关键词： Coalbed methane reservoir Butt cleat Propagation mechanisms Fracture morphology Step-like fractures

Electrolyte-mediated dense integration of graphene-MXene films for high volumetric capacitance flexible supercapacitors

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Nano Research 2021年第3期14卷 699-706页

作者： Min zhang Jun Cao Yi Wang jia Song Tianci jiang Yanyu zhang Weimeng Si Xiaowei Li Bo Meng Guangwu Wen School of Chemistry and Chemical Engineering Shandong University of TechnologyZibo255049China School of Materials Science and Engineering Shandong University of TechnologyZibo255049China School of Chemical Engineering and Technology Tianjin UniversityTianjin300071China Key Laboratory of Advanced Energy Materials Chemistry(Ministry of Education) College of ChemistryNankai UniversityTianjin300072China

High conductivity two-dimensional(2D)materials have been proved to be potential electrode materials for flexible supercapacitors because of its outstanding chemical and physical ***,electrodes based on 2D materials always suffer from limited electrolyte-accessible surface due to the restacking of the 2D sheets,hindering the full utilization of their surface *** this regard,an electrolyte-mediated method is used to integrate dense structure reduced graphene oxide/MXene(RGM)-electrolyte composite *** such composite films,reduced graphene oxide(RGO)and MXene sheets are controllable assembly in compact layered structure with electrolyte filled between the *** electrolyte layer between RGO and MXene sheets forms continuous ion transport channels in the composite ***,the RGM-electrolyte composite films can be used directly as self-supporting electrodes for supercapacitors without additional conductive agents and *** a result,the composite films demonstrate enhanced volumetric specific capacity,improved volumetric energy density and higher power density compared with both pure RGO electrode and porous composite electrode prepared by traditional ***,when the mass ratio of MXene is 30%,the electrode delivers a volumetric specific capacity of 454.9 F·cm^(−3) with a high energy density of 39.4 Wh·L^(−1).More importantly,supercapacitors based on the composite films exhibit good flexibility electrochemical *** investigation provides a new approach to synthesize dense structure films based on 2D materials for application in high volumetric capacitance flexible supercapacitors.

关键词： electrolyte-mediated dense structure continuous ion transport channels composite film flexible supercapacitors high energy density

Adsorption properties of the double-imprinted electrospun crosslinked chitosan nanofibers

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Chinese Chemical Letters 2019年第3期30卷 762-766页

作者： Yan Li Mengqi Li Jie zhang Xiaoyan xu School of Materials Science and Engineering Tongji University Key Laboratory of Synthetic and Self-Assembly Chemistry for Organic Functional Molecules Shanghai Institute of Organic Chemistry Chinese Academy of Sciences

The adsorption properties of the Pb(Ⅱ)-Cd(Ⅱ) double-imprinted electrospun crosslinked chitosan nanofibers(Pd/Cd-DIECCNs) prepared by electropspinning and imprinting process for the removal of Pb(Ⅱ) and Cd(Ⅱ) from aqueous solutions were investigated. The prepared nanofibers were characterized by scanning electron microscope(SEM) analysis. Under the optimum experimental conditions, the minimum fiber average diameter was obtained 110 nm. Then the adsorption experiments were carried out to study the effect of different adsorption parameters, such as pH, the ratio between Pb(Ⅱ) and Cd(Ⅱ)in the mixed solutions, contact time, the Pd/Cd-DIECCNs dose and temperature in a batch system. The Extended Langmuir model was applied to describe the equilibrium data of Pb(Ⅱ) and Cd(Ⅱ). The maximum adsorption capacities of the Pd/Cd-DIECCNs arrived at 567 mg/g for Pb(Ⅱ) and 341 mg/g for Cd(Ⅱ), respectively.

关键词： Chitosan Double imprinted Crosslinked Electrospun Adsorption

Bilayer Structured Nanowire-array and Nanotube-cluster TiO2 Photoanode for Efficient Dye-sensitized Solar Cells

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Chemical Research in Chinese Universities 2015年第3期31卷 412-417页

作者： YU Jun zhang Chengkai ZHUANG jia QIN Haiyang HE Quangui LIANG Qiumei School of Materials Science and Engineering Southwest Petroleum University Chengdu 610500 P.R.China

Nanowire-array nanotube-cluster bilayer TiO2 films, consisting of nanowire-array at the bottom layer and nanotube-cluster at the top layer were prepared via a two-step hydrothermal method. One step was a growth process and the other was an etching process. Etching process was used to acquire nanowire-array with a small diameter of 20--25 nm of the nanowire and nanotube-cluster. The bilayer nanostructured films were then modified with TiCI4. Villous TiO2 attached to both the inside and outside wails of the nanotube cluster was obtained only by changing the traditional concentration of TiCla-treatment to 0.2 mol/L. The novel bilayer photoanode finally revealed a higher effi- ciency of 5.25% when used in dye-sensitized solar cells（DSSCs）.

关键词： Bilayer structure Etching Titanium oxide Photoanode Dye-sensitized solar cell

Association of cholesterol with risk of pancreatic cancer:A meta-analysis

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World Journal of Gastroenterology 2015年第12期21卷 3711-3719页

作者： jia Wang Wei-Jing Wang Long Zhai Dong-Feng zhang Department of Epidemiology and Health Statistics Qingdao University Medical College

AIM: To evaluate the effect of dietary cholesterol and serum total cholesterol(TC) on the risk of pancreatic cancer. METHODS: A literature search was performed up to June 2014 in Pub Med, EMBASE, China National Knowledge Infrastructure and China Biology Medicalliterature database for relevant articles published in English or Chinese. Pooled relative risks(RRs) with 95% confidence intervals(CIs) were calculated with a random-effects model. RESULTS: We included 14 published articles with 439355 participants for dietary cholesterol, and 6 published articles with 1805697 participants for serum TC. For the highest vs lowest category of dietary cholesterol, the pooled RR(95%CI) of pancreatic cancer was 1.308(1.097-1.559). After excluding two studies(RR > 3.0), the pooled RR(95%CI) was 1.204(1.050-1.380). In subgroup analysis stratified by study design, the pooled RRs(95%CIs) were 1.523(1.226-1.893) for case-control studies and 1.023(0.871-1.200) for cohort studies. The association of dietary cholesterol with the risk of pancreatic cancer was significant for studies conducted in North America [1.275(1.058-1.537)] and others [2.495(1.565-3.977)], but not in Europe [1.149(0.863-1.531)]. No significant association [1.003(0.859-1.171)] was found between the risk of pancreatic cancer and serum TC. CONCLUSION: Dietary cholesterol may be associated with an increased risk of pancreatic cancer in worldwide populations, except for Europeans. The results need to be confirmed further.

关键词： Dietary cholesterol Serum total cholesterol Pancre

Effect of Solid Solution Treatment on Microstructure of Fe-Ni Based High Strength Low Thermal Expansion Alloy

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Journal of Iron and Steel Research International 2008年第1期15卷 75-78页

作者： zhang jian-fu TU Yi-fan xu Jin zhang jian-sheng zhang Jing-lin Central Iron and Steel Research Institute Beijing 100081 China University of Science and Technology Beijing Beijing 100083 China

The influence of solid solution treatments on the dissolution of carbides precipitates,the grain size,and the hardness of high strength low expansion alloy were investigated through XRD analysis,microstructure observations,and theoretical *** was seen that most primary Mo2C type carbide band dissolved in a temperature range of 1 100-1 150 ℃.When the temperature was over 1 200 ℃,the grain size increased remarkably,which led to the reduction of hardness.

关键词： high strength low expansion alloy solid solution temperature~ microstructure carbide dissolution

Recurrent endophthalmitis caused by intraocular eyelashes

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International Journal of Ophthalmology(English edition) 2019年第2期12卷 346-347页

作者： jia-Wei Wang Xiao-Yang zhang Jing Wang Han zhang Eye Center of Shandong University the Second Hospital of Shandong University Shandong University Jinan Aier Eye Hospital

Dear Editor,The presence of intraocular eyelashes following a penetrating injury or surgical intervention is rarely encountered and is usually an incidental finding in clinic1' There is significant individual differen... 详细信息

关键词： Recurrent endophthalmitis intraocular eyelashes