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动物医学进展 2024年第2期45卷 142-144页

作者：张维虎廊坊市动物疫病预防控制中心河北廊坊065000

青光眼是小动物临床眼科常见疾病,病因可分为原发性与继发性。在猫科动物中原发性较罕见,临床上更常见的是继发性青光眼,多与眼内炎症有关。现将1例猫继发性青光眼的诊治方法报道,以期为猫青光眼临床诊断和治疗提供参考。

关键词：猫继发性青光眼诊断治疗

Bi-variable damage model for fatigue life prediction of metal components

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Acta Mechanica Sinica 2011年第3期27卷 416-425页

作者： Miao zhang Qing-Chun Meng Xing zhang wei-Ping hu Division 508 School of Aeronautic Science and Engineering Beihang University 100191 Beijing China

Based on the theory of continuum damage mechanics,a bi-variable damage mechanics model is developed,which,according to thermodynamics,is accessible to derivation of damage driving force,damage evolution equation and damage evolution criteria. Furthermore,damage evolution equations of time rate are established by the generalized Drucker＇s postulate. The damage evolution equation of cycle rate is obtained by integrating the time damage evolution equations,and the fatigue life prediction method for smooth specimens under repeated loading with constant strain amplitude is constructed. Likewise,for notched specimens under the repeated loading with constant strain amplitude,the fatigue life prediction method is obtained on the ground of the theory of conservative integral in damage mechanics. Thus,the material parameters in the damage evolution equation can be obtained by reference to the fatigue test results of standard specimens with stress concentration factor equal to 1,2 and 3.

关键词： Bi-variable damage model - Damage evolution equation . Life prediction - Fatigue . Damage mechanics

In situ measured growth rates of bainite plates in an Fe-C-Mn-Si superbainitic steel

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International Journal of Minerals,Metallurgy and Materials 2014年第4期21卷 371-378页

作者： zhang-wei hu Guang Xu Hai-jiang hu Li Wang Zheng-liang Xue Key Laboratory for Ferrous Metallurgy and Resources Utilization of the Ministry of Education Wuhan University of Science and Technology State Key Laboratory of Development and Application Technology of Automotive Steels (Baosteel Group)

The growth rates of bainite plates in an Fe-C-Mn-Si superbainitie steel were investigated by in situ observation. The lengthening rates of ferrite bainite during both cooling and isothermal holding processes were observed and the growth rates of bainite plates nucleating at grain boundaries, within grains and on preformed bainite were measured. It is indicated that the lengthening rates of bainite plates during the cooling and isothermal processes were different, and that the growth rates of bainite plates nucleating at different types of sites also demon- strated diversity. The bainite plates initiating at [vain boundaries during cooling grew the fastest, while the plates nucleating on preformed bainite did the slowest. However, the growth rate of the bainite plates nucleating at grain boundaries during isothermal transformation de- creased the most, whereas the bainite plates initiating within grains grew the fastest. In addition, the growth rate of ferrite bainite in the study supported the diffusion transformation mechanism of bainite from the viewooint of ~rowth rate.

关键词： bainitic steel bainite growth rate cooling isothermal treatment phase transitions

Enhanced Ferroelectric Properties of Predominantly (100)-oriented Ca_(0.4)Sr_(0.6)Bi_4Ti_4O_(15) Thin Films on Pt/Ti/SiO_2/Si Substrates

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Journal of Materials Science & Technology 2010年第11期26卷 981-985页

作者： Suhue Fan Quande Che Fengqing zhang Ran Yu wei hu College of Material Science and Engineering Shandong Jianzhu University Jinan 250101 China

Predominantly （100）-oriented Ca0.4Sr0.6Bi4Ti4O15 （C0.4S0.6BTi） thin films were prepared on Pt （111）/Ti/SiO2/Si substrates by a sol-gel method at annealing temperatures ranging from 650 to 850 ℃.The growth mode of the predominantly （100）-oriented C0.4S0.6 BTi thin films fabricated by the sequential layer annealing was discussed based on the structure evolution with the annealing *** remnant polarization and coercive field of the C0.4S0.6 BTi film annealed at 800 ℃ are 16.1 μC/cm 2 and 85 kV/cm,*** evident fatigue can be observed after 10 9 switching cycles.

关键词： Ca0.4Sr0.6Bi4Ti4O15 Ferroelectric film Orientation

First-Principles Study of Fe-Doped ZnO Nanowires

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Chinese Physics Letters 2011年第12期28卷 207-210页

作者： zhang Fu-Chun zhang wei-hu DONG Jun-Tang zhang Zhi-Yong College of Physics and Electronic Information Yan'an UniversityYan'an 716000 Information Science and Technology Institution Northwest UniversityXi'an 710127

Using first-principles theory,we predict magnetic,electronic and optical properties in Fe-doped ZnO *** results show that ferromagnetic(FM)coupling of configuration V is the most stable,and the strong hybridization effect between Fe 3d and O 2p states is found near the Fermi level,and it is obvious that the ferromagnetic system is electron−spin polarization of 100%and *** antiferromagnetic(AFM)coupling,the system generates small spin polarization near the Fermi level,indicating *** magnetic moments mainly arise from Fe 3d *** addition,the results of optical properties show that the Fe-doped ZnO nanowires have apparent absorption peaks in the ultraviolet band and that there is a small red shift and a strong blue shift in the near and far ultraviolet band,indicating that Fe-doped ZnO nanowires are a type of magneto-optical materials with great promise.

关键词： nanowires ultraviolet coupling

First-principles calculations and experimental studies of Sn-Zn alloys as negative electrode materials for lithium-ion batteries

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Rare Metals 2011年第2期30卷 160-165页

作者： RU Qiang PENG wei zhang Zhiwen hu Shejun LI Yanling Laboratory of Quantum Information Technology School of Physics and Telecommunication Engineering South China Normal University Guangzhou 510006 China

The physical characters and electrochemical properties of various phases in a Sn-Zn electrode, such as formation energy, plateau potential, specific capacity, as well as volume expansion, were calculated by the first-principles plane-wave pseudo-potential method based on the den- sity functional theory. Sn-Zn films were also deposited on copper foils by an electroless plating technique. The actual composition and chemical characters were explored by scanning electron microscopy （SEM）, X-ray diffraction （XRD）, plasma atomic emission spectrometry （ICP）, and constant current charge/discharge measurements （CC）. The results show that separation phases with tin and zinc including a small quantity of Cu6Sn5 phase were obtained, the initial lithium insertion capacity of the Sn-Zn film was 661 mAh/g, and obvious potential pla- teaus of about 0.4 V and 0.7 V were displayed, which is in accordance with the results of theoretical calculations. The capacity of the Sn-Zn film decreased seriously with the increase of cycle number.

关键词： lithium batteries electrochemical electrodes tin alloys first-principles calculations

Does antecolic reconstruction for duodenojejunostomy improve delayed gastric emptying after pylorus-preserving pancreaticoduodenectomy? A systematic review and meta-analysis

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World Journal of Gastroenterology 2012年第43期18卷 6315-6323页

作者： An-Ping Su Shuang-Shuang Cao Yi zhang Zhao-Da zhang wei-Ming hu Bo-Le Tian Department of Hepatobiliopancreatic Surgery West China Hospital Sichuan University Chengdu 610041 Sichuan Province China

AIM:To evaluate whether antecolic reconstruction for duodenojejunostomy (DJ) can decrease delayed gastric emptying (DGE) rate after pylorus-preserving pancreaticoduodenectomy (PPPD) through literature review and meta-analysis. METHODS:Articles published between January 1991 and April 2012 comparing antecolic and retrocolic reconstruction for DJ after PPPD were retrieved from the databases of MEDLINE (PubMed), EMBASE, OVID and Cochrane Library Central. The primary outcome of interest was DGE. Either fixed effects model or random effects model was used to assess the pooled effect based on the heterogeneity. RESULTS:Five articles were identified for inclusion:two randomized controlled trials and three non-randomized controlled trials. The meta-analysis revealed that antecolic reconstruction for DJ after PPPD was associated with a statistically significant decrease in the incidence of DGE [odds ratio (OR), 0.06; 95% CI, 0.02-0.17; P < 0.00 001] and intra-operative blood loss [mean difference (MD), -317.68; 95% CI, -416.67 to -218.70; P < 0.00 001]. There was no significant difference between the groups of antecolic and retrocolic reconstruction in operative time (MD, 25.23; 95% CI, -14.37 to 64.83; P = 0.21), postoperative mortality, overall morbidity (OR, 0.54; 95% CI, 0.20-1.46; P = 0.22) and length of postoperative hospital stay (MD, -9.08; 95% CI, -21.28 to 3.11; P = 0.14). CONCLUSION:Antecolic reconstruction for DJ can decrease the DGE rate after PPPD.

关键词： Pylorus-preserving pancreaticoduodenectomy Delayed gastric emptying Antecolic reconstruction Retrocolic reconstruction Duodenojejunostomy

Experimental and numerical interpretation on composite foundation consisting of soil-cement column within warm and ice-rich frozen soil

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Journal of Mountain Science 2024年第1期21卷 313-321页

作者： WANG Honglei zhang Jianming wei Shoucai SUN Zhizhong zhang hu School of Civil Engineering Hebei University of EngineeringHandan 056038China State Key Laboratory of Frozen Soil Engineering Northwest Institute of Eco-Environment and ResourcesChinese Academy of SciencesLanzhou 730000China Second Geological Brigade Bureau of Geology and Mineral Resources Exploration and DevelopmentLhasa 850000China Da Xing’anling Observation and Research Station of Frozen Ground Engineering and Environment Northwest Institute of Eco-Environment and ResourcesChinese Academy of SciencesJiagedaqi 165100China School of Civil Engineering Northeast Forestry UniversityHarbin 150040China

Affected by climate warming and anthropogenic disturbances, the thermo-mechanical stability of warm and ice-rich frozen ground along the Qinghai-Tibet engineering corridor(QTEC) is continuously decreased, which may delay the construction of major projects in the future. In this study, based on chemical stabilization of warm and icerich frozen ground, the soil-cement column(SCC) for ground improvement was recommended to reinforce the foundations in warm and ice-rich permafrost regions. To explore the validity of countermeasures mentioned above, both the original foundation and the composite foundation consisting of SCC with soil temperature of -1.0℃ were prepared in the laboratory, and then the plate loading tests were carried out. The laboratory investigations indicated that the bearing capacity of composite foundation consisting of SCC was higher than that of original foundation, and the total deformation of original foundation was greater than that of composite foundation, meaning that overall stability of foundation with warm and ice-rich frozen soil can be improved by SCC installation. Meanwhile, a numerical model considering the interface interaction between frozen soil and SCC was established for interpretating the bearing mechanism of composite foundation. The numerical investigations revealed that the SCC within composite foundation was responsible for the more applied load, and the applied load can be delivered to deeper zone in depth due to the SCC installation, which was favorable for improving the bearing characteristic of composite foundation. The investigations provide the valuable guideline for the choice of engineering supporting techniques to major projects within the QTEC.

关键词： Chemical stabilization Ground improvement Composite foundation Frozen soil engineering Qinghai-Tibet engineering corridor

Application of the finite analytic numerical method to a flowdependent variational data assimilation

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Acta Oceanologica Sinica 2024年第3期43卷 30-39页

作者： Yan hu wei Li Xuefeng zhang Guimei Liu Liang zhang Tianjin Key Laboratory for Marine Environmental Research and Service School of Marine Science and TechnologyTianjin UniversityTianjin 300072China School of Marine Science and Technology Tianjin UniversityTianjin 300072China National Marine Environmental Forecasting Center Ministry of Natural ResourcesBeijing 100081China

An anisotropic diffusion filter can be used to model a flow-dependent background error covariance matrix,which can be achieved by solving the advection-diffusion *** of the directionality of the advection term,the discrete method needs to be chosen very *** finite analytic method is an alternative scheme to solve the advection-diffusion *** a combination of analytical and numerical methods,it not only has high calculation accuracy but also holds the characteristic of the auto *** demonstrate its ability,the one-dimensional steady and unsteady advection-diffusion equation numerical examples are respectively solved by the finite analytic *** more widely used upwind difference method is used as a control *** result indicates that the finite analytic method has higher accuracy than the upwind difference *** the two-dimensional case,the finite analytic method still has a better *** the three-dimensional variational assimilation experiment,the finite analytic method can effectively improve analysis field accuracy,and its effect is significantly better than the upwind difference and the central difference ***,it is still a more effective solution method in the strong flow region where the advective-diffusion filter performs most prominently.

关键词： finite analytic method advection-diffusion equation data assimilation flow-dependent

Tunable luminescence of Bi^(3+)/Eu^(3+)-doped SiO_(2)-Al_(2)O_(3)-MCO_(3)(M=Ca,Sr,Ba) glasses for WLED

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Journal of Rare Earths 2024年第9期42卷 1652-1657,I0001页

作者： Falin zhang Xiaoying Liang Rongfei wei Hai Guo Fangfang hu Department of Physics Zhejiang Normal UniversityJinhua321004China

In this work,a group of Bi^(3+)/Eu^(3+)-doped SiO2-Al_(2)O_(3)-MCO_(3)(M=Ca,Sr,Ba) glasses were fabricated through melt-quenching *** structure and photoluminescence characters were studied via Xray diffraction(XRD),UV-Vis transmission spectra(TRS),excitation spectra,emission spectra and decay *** XRD results show that no nano-crystal phase forms in glass matrix with different doping concentrations of Bi^(3+)and Eu^(3+)*** regulating optical alkalinity value,the intensity of Bi^(3+)ions increases and the peak position shifts to red *** Bi^(3+)/Eu^(3+) co-doped glasses show a blue-white-yellow-red luminescence by changing concentration of Eu^(3+) *** transfer efficiency from Bi^(3+) to Eu^(3+) can reach as high as 10.54%.At 423 K, the emission intensity of 55SiO_(2)-10Al_(2)O_(3)-35BaO-0.25Bi_(2)O_(3)(GBE0.5) is 31.1% of that at 308 ***,the activation energy of the glass matrix is 0.251 *** results suggest that these Bi^(3+)/Eu^(3+) co-doped glass samples possess potential application in LED field.

关键词： Bi^(3+) Eu^(3+) Glass White light-emitting diode Energy transfer Rare earths