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Microstructural evolution,mechanical properties and degradation mechanism of PS-PVD quasi-columnar thermal barrier coatings exposed to glassy CMAS deposits

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Rare Metals 2024年第7期43卷 3329-3340页

作者： Zi-Yue Yu liang-liang Wei Xing-Ye guo Bao-Peng Zhang qing He Hong-Bo guo School of Materials Science and Engineering Beihang UniversityBeijing100191China Key Laboratory of High-Temperature Structure Materials and Protective Coatings(Ministry of Industry and Information Technology) Beihang UniversityBeijing 100191China Surface Engineering Research Institute Chinese Academy of Agricultural Mechanization SciencesBeijing 100083China

Thermal barrier coatings(TBCs) applied in aeroengines tend to be attacked by molten calcia-magnesiaalumino-silicate(CMAS) at high operating ***-stabilized zirconia(YSZ) coatings with quasicolumnar microstructure were fabricated by plasma spray physical vapor deposition(PS-PVD) *** chemic al changes,micros tructural transform ation,mechanical properties and degradation mechanisms of the CM AS-interacted TBCs in the thermal cycling tests were *** YSZ grains were dissolved in the CMAS melts,and then the ZrO_(2) grains were reprecipitated with spherical shape,accompanying with phase transformation from tetragonal(t) to monoclinic(m).The thermal cycling tests reveal that the YSZ coating fails at the early stage due to the attack of *** fractures in intracolumns lead to partial spallation of the *** failure of the coating occurs at the interfaces between thermally grown oxides(TGO) layer and YSZ topcoat;especially,the hardness and Young's modulus of the YSZ coatings increase intensively,as the coatings were infiltrated by the CMAS for a long time.

关键词： CMAS Thermal barrier coatings Young's modulus Thermal cycling behavior PS-PVD

Method for rapid warning and activity concentration estimates in online waterγ-spectrometry systems

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Nuclear Science and Techniques 2024年第3期35卷 1-12页

作者： Meng Wang Yi Gu Mao-Lin Xiong liang-Quan Ge qing-Xian Zhang guo-Qiang Zeng Heng Lu Sheng-liang guo College of Nuclear Technology and Automation Engineering Chengdu University of TechnologyChengdu 610059China Applied Nuclear Technology in Geosciences Key Laboratory of Sichuan Province (Chengdu University of Technology)Chengdu 610059China Chengdu New Ray Technology Co.Ltd Chengdu 610052China

Onlineγ-spectrometry systems for inland waters,most of which extract samples in situ and in real time,are able to produce reliable activity concentration measurements for waterborne radionuclides only when they are distributed relatively uniformly and enter into a steady-state diffusion regime in the measurement *** protect residents’health and ensure the safety of the living environment,better timeliness is required for this measurement *** address this issue,this study established a mathematical model of the online waterγ-spectrometry system so that rapid warning and activity estimates can be obtained for water under non-steady-state(NSS)*** addition,the detection efficiency of the detector for radionuclides during the NSS diffusion process was determined by applying the computational fluid dynamics technique in conjunction with Monte Carlo *** this basis,a method was developed that allowed the online waterγ-spectrometry system to provide rapid warning and activity concentration estimates for radionuclides in *** analysis of the NSS-mode measurements of^(40)K radioactive solutions with different activity concentrations determined the optimum warning threshold and measurement time for producing accurate activity concentration estimates for *** experimental results show that the proposed NSS measurement method is able to give warning and yield accurate activity concentration estimates for radionuclides 55.42 and 69.42 min after the entry of a 10 Bq/L^(40)K radioactive solution into the measurement chamber,*** times are much shorter than the 90 min required by the conventional measurement ***,the NSS measurement method allows the measurement system to give rapid(within approximately 15 min)warning when the activity concentrations of some radionuclides reach their respective limits stipulated in the Guidelines for Drinking-water Quality of the WHO,suggesting that this method con

关键词： Water radioactivity monitoring Dynamic detection efficiency Rapid warning Activity estimation

Depression of biofilm formation and antibiotic resistance by sarA disruption in Staphylococcus epidermidis

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World Journal of Gastroenterology 2006年第25期12卷 4009-4013页

作者： Ju-Hong Tao Chang-Sheng Fan Shan-E Gao Hai-Jiao Wang guo-Xin liang qing Zhang Department of Microbiology School of Life Sciences Fudan University Shanghai 200433 China

AIM： To study the effects of disruption of sarA gene on biofilm formation and antibiotic resistance of Staphylococcus epidermidis （ S. epiderrnidis）. METHODS： In order to disrupt sarA gene, the double- crossover homologous recombination was applied in S. epiderrnidis RP62A, and tetracycline resistance gene （tet） was used as the selective marker which was amplified by PCR from the pBR322 and inserted into the locus between sarA upstream and downstream, resulting in pBT2ΔsarA. By electroporation, the plasmid pBT2ΔsarA was transformed into S. epiderrnidis. Gene transcription was detected by real-time reverse transcription-PCR （RT-PCR）. Determination of biofilm was performed in 96-well flat-bottomed culture plates, and antibiotic resistance was analyzed with test tube culture by spectrophotometry at 570 nm respectively. RESULTS： A sarA disrupted strain named S. epiderrnidis RP62AΔsarA was constructed, which was completely defective in biofilm formation, while the sarA complement strain RP62AΔsarA （pHPS9sarA） restored the biofilm formation phenotype. Additionally, the knockout of sarA resulted in decreased erythromycin and kanamycin resistance of S. epiderrnidis RP62A. Compared to the original strain, S. epiderrnidis RP62AΔsarA had an increase of the sensitivity to erythromycin at 200-400 μg/mL and kanamycin at 200-800 μg/mL respectively. CONCLUSION： The knockout of sarA can result in the defect in biofilm formation and the decreased erythromycin and kanamycin resistance in S. epiderrnidis RP62A.

关键词： sarA Biofilm Antibiotic resistance Staphylococcus epidermidis

Seminal plasma miR-192a： a biomarker predicting successful resolution of nonobstructive azoospermia following varicocele repair

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Asian Journal of Andrology 2018年第4期20卷 396-399页

作者： Er-Lei Zhi guo-qing liang Peng Li Hui-Xing Chen Ru-Hui Tian Peng Xu Zheng Li Department of Andrology Center for Men's Health Department of ART Institute of Urologic Medical Center Shanghai General Hospital Shanghai Key Lab of Reproductive Medicine Shanghai Jiao Tong University 100 Haining Road Shanghai 200080 China Department of Andrology Seventh People's Hospital of Shangha University of TCM Shanghai 200000 China Oriental Jinghua Hospital of Shenyang Department of ART 156 Nanjing Road Shenyang 110005 China

This study was performed to investigate a potential marker for the presence of spermatozoa in the ejaculate following varicocelectomy in Chinese men with nonobstructive azoospermia and varicoceles. The micro-RNA （miR）-192a levels in seminal plasma and testicular tissue were evaluated by quantitative real-time polymerase chain reaction from 60 men with nonobstructive azoospermia and varicoceles （Group A： 27 men with spermatozoa found in the ejaculate after surgery; Group B： 33 men without spermatozoa found in the ejaculate after surgery） and 30 controls. The seminal plasma and testicular tissue miR-192a levels were higher in Group B than in Group A and the controls （P〈 0.001）, and there was no significant difference between Group A and the controls （P〉 0.05）. Apoptosis and proliferation assays with miR mimics and inhibitors showed that miR-192a induced GC-2 cell apoptosis through the activation of Caspase-3 protein. Thus, seminal plasma miR-192a appears to be a potential marker for successfully indicating spermatozoa in the ejaculate following microsurgical varicocelectomy in men with nonobstructive azoospermia and varicoceles. Seminal plasma miR-192a may be a useful clinical marker for prescreening to determine which patients with nonobstructive azoospermia and varicoceles would benefit from varicocelectomy.

关键词： miR-192a nonobstructive azoospermia seminal plasma varicocelectomy

Research on Digital Models for Product Design and Manufacture

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厦门大学学报（自然科学版） 2002年第S1期41卷 155-156页

作者： WANG Zhong-qing, guo Chun-liang (East China Jiaotong University, Nanchang 330013, China)

CAD/CAM integrate technology has been drawn to much a ttention and becomes one of the focus of the international academic and commerci al research, Through efforts nearly 10 years, remarkable progress has been made in the 3-dimension feature parametric modeling. UG, SOLIDWORK and MDT apply the se technology with respective features. However, no distinct development has bee n made in the digital models from geometric feature to manufacture feature. Prod uct information expression and the basic model frame of data exchange have been proposed based on STEP standards, but it is quite difficult to some extent ensur e the operability, due to the complexity in application. The models addressed in this paper divide the shared digital models (not data models) for product desig n and manufacture into five parts: ①Digital product 3D molding design; ②Digit al product technology process design; ③Digital product assembly design; ④Digit al product manufacture process design; ⑤Digital product management design. The resource model should not be included. And It should be a peripheral model i n product design; which is the innovative viewpoint of this paper. The core of above-mentioned five models is to access the digital model from the solid unit feature. Product definition should be determined on the basis of solid unit, and solid unit should follow the rules of "generation of machining processing", Therefore, the author also proposed the Constructing Cutting Geomet ry Method (CCG) in IMCC’2000. In this way, the integration of "forming - processing - assembling - machining - management" can be obtained. This is th e core originality of the paper.

关键词： product digitization solid unit technique CAD CAPP CAM

Design parameter optimization method for a prestressed steel structure driven by multi-factor coupling

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Frontiers of Structural and Civil Engineering 2024年第7期18卷 1066-1083页

作者： guo-liang SHI Zhan-Sheng LIU De-Chun LU qing-Wen ZHANG Majid DEZHKAM Ze-Qiang WANG Faculty of Architecture Civil and Transportation EngineeringBeijing University of TechnologyBeijing 100124China The Key Laboratory of Urban Security and Disaster Engineering of the Ministry of Education Beijing University of TechnologyBeijing 100124China Beijing Building Construction Research Institute Co. Ltd.Beijing 100039China

To achieve efficient structural design,it is crucial to reduce the cost of materials while ensuring structural *** study proposes an optimization method for design parameters(DPs)in a prestressed steel structure driven by multi-factor *** accomplish this,a numerical proxy model of prestressed steel structures is established with integration of DPs and mechanical parameters(MPs).A data association-parameter analysis-optimization selection system is established.A correlation between DPs and MPs is established using a back propagation(BP)neural *** correlation provides samples for parameter analysis and optimization *** are used to characterize the safety of the *** on the safety grade analysis,the key DPs that affect the mechanical properties of the structure are obtained.A mapping function is created to match the MPs and the key *** optimal structural DPs are obtained by setting structural materials as the optimization objective and safety energy as the constraint *** theoretical model is applied to an 80-m-span gymnasium and verified with a scale test physical *** MPs obtained using the proposed method are in good agreement with the experimental *** with the traditional design method,the design cycle can be shortened by more than 90%.Driven by the optimal selection method,a saving of more than 20% can be achieved through reduction of structural material ***,the cross-sectional dimensions of radial cables have a substantial influence on vertical *** initial tension and cross-sectional size of the upper radial cable exhibit the most pronounced impact on the stress distribution in that *** initial tension and cross-sectional size of the lower radial cable hold the greatest sway over the stress distribution in that cable.

关键词： structure design association relationship performance analysis optimum selection experimental verification

Recent progresses in the development of tubular segmented-in-series solid oxide fuel cells:Experimental and numerical study

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International Journal of Minerals,Metallurgy and Materials 2024年第3期31卷 427-442页

作者： Shuo Han Tao Wei Sijia Wang Yanlong Zhu Xingtong guo liang He Xiongzhuang Li qing Huang Daifen Chen School of Energy and Power Jiangsu University of Science and TechnologyZhenjiang 212003China College of Materials Science and Engineering Nanjing Forestry UniversityNanjing 210037China

Solid oxide fuel cells(SOFCs)have attracted a great deal of interest because they have the highest efficiency without using any noble metal as catalysts among all the fuel cell ***,traditional SOFCs suffer from having a higher volume,current leakage,complex connections,and difficulty in gas *** solve these problems,Rolls-Royce has fabricated a simple design by stacking cells in series on an insulating porous support,resulting in the tubular segmented-in-series solid oxide fuel cells(SIS-SOFCs),which achieved higher output *** work systematically reviews recent advances in the structures,preparation methods,perform-ances,and stability of tubular SIS-SOFCs in experimental and numerical ***,the challenges and future development of tubular SIS-SOFCs are also *** findings of this work can help guide the direction and inspire innovation of future development in this field.

关键词： solid oxide fuel cell segmented-in-series tubular experimental study numerical study

Forming process chain for manufacturing complex conical-section profiled rings:On a co-design method

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Chinese Journal of Aeronautics 2024年第6期37卷 485-503页

作者： Lei liang Chaojiang ZOU lianggang guo State Key Laboratory of Solidification Processing School of Materials Science and EngineeringNorthwestern Polytechnical UniversityXi’an 710072China Guizhou Aviation Technology Development Co.Ltd Guiyang 550081China

The final quality of complex conical-section rings depends on co-design of multiple processes in forming process *** this study,for a complex aeroengine casing ring with a large slope and a flange on its end,a co-design method of the forming process chain is put forward towards the objective of precision forming,which not only proposes a standard process route composed of multiple processes of upsetting,punching,rectangular ring rolling,loose tooling forging and profiled ring rolling,but also presents co-design methods of dies and blanks for all the *** profiled ring rolling,a design method of preformed blank that makes the blank and the target conical-section ring have the same axial volume distribution is *** the method,the axial metal redistribution during the process can be alleviated greatly thus improving the forming stability and precision of the *** on the geometric features of designed preformed blank,design methods of blanks and dies for loose tolling forging,rectangular ring rolling,punching and upsetting are proposed *** view of the key roles of loose tooling forging(manufacturing the preformed blank)and profiled ring rolling on the final quality of the conical ring parts,inherited FE simulations for these two processes are performed to verify the proposed design methods and determine appropriate design *** is demonstrated that the proposed design method has significant advantages in improving forming ***,a suggestive value 1.5 of the rolling ratio for profiled ring rolling(a key design parameter)is given based on comprehensive consideration of multiple indicators such as ring roundness,deformation uniformity and forming *** corresponding industrial experiments performed illustrate that a high forming precision of the conical-section aeroengine casing ring is achieved.

关键词： Complex conical-section ring Co-design of forming process chain Profiled ringrolling Preformed blank Loose tooling forging

Sperm Donors in Shanghai,China:A Study of Motivations,Characteristics,and Semen Parameters of Actual Sperm Donors

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Reproductive and Developmental Medicine 2021年第4期5卷 213-219页

作者： Xiao Wang Min-Xin Chen Feng Zhang guo-qing liang Hong Zhu Bai-Lan Feng Zhi-Wen Tao Feng Jiang Department of Human Sperm Bank and President Office Obstetrics&Gynecology Hospital of Fudan UniversityShanghai 200000China Department of Andrology Shanghai JIAI Genetics&IVF institute-China USA CenterShanghai 200011China

Objective:To identify the sociodemographic characteristics,motivations,and semen parameters of sperm donors in Shanghai,***:The participants were sperm donors associated with the Human Sperm Bank of Fudan University in Shanghai,*** the 334 sperm donors that applied for participation,329 completed the survey *** responses obtained in the questionnaire and face-to-face interviews were used to investigate the donor motivations and characteristics,and the semen quality was examined to identify the sperm ***:In terms of the sociodemographic characteristics,an altruistic donor in this study was aged between 26 and 30 years,was single,did not have a child,had a college or undergraduate education level,was of the Han ethnicity,and worked full *** strongest motivation highlighted by sperm donors was a donation for altruistic(26.4%,n=87)*** second-highest rated motivation was curiosity(20.7%,n=68),followed by a desire to procreate(17.9%,n=59)."Complimentary body checks"(14.3%,n=47)and"financial incentives"(14.7%,n=47)were regarded as less *** average semen parameters of the 329 donors were as follows:the semen volume was 3.39±1.21 mL,the semen concentration was 82.75×10^(6)/mL,the progressive motility rate(PR%)was 63.77%±3.13%,the total motility rate was 66.26%,the total progressive motile count was 158.31%±54.43×10^(6)/mL,and the round cell concentration was 0.38±0.51×10^(6)/*** PR%of the procreation motivation group was significantly higher than that of the other motivation groups(P<0.05).Conclusions:Sperm donors in Shanghai,China,are altruistic about their donation,although curiosity is also a key *** addition,the decisions of donors are culturally influenced,and the motivation to procreate may influence the PR%.

关键词： Assisted Reproductive Technology Donation Semen Parameters Sperm Donors