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Investigation of the role of aziridine bonding agents on the aging of the composite solid rocket propellant(CSRP)

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航空动力学报 2008年第11期23卷 2101-2106页

作者： Amged A Ali zhang jian-wei CAI Guo-biao School of Astronautics Beijing University of Aeronautics and Astronautics Beijing 100191 China

The role of bonding agents on the aging characteristics is one of the important research *** program of the prepared propellant samples was conducting as follows:Five samples,two free of bonding agents,and three containing an aziridine based bonding agents(MAPO,HX-752,MAT4),four samples based on different bonding and curing agents all were aged at 70 ℃.The prepared bonding agent "MAT4" gave remarkable improvements and resulted in highly stable mechanical properties comparing with HX-752 or *** selected bonding agents family inhibited the rate of decomposition of the propellants during the aging periods and supported the propellant matrix against decomposition at the elevated temperatures.

关键词：氮丙啶黏结剂老化现象复合固体火箭推进剂航空动力系统

An iterative approach for modal analysis of solid rocket motor incorporating frequency dependent modulus

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航空动力学报 2013年第2期28卷 452-458页

作者： Muhammad Adnan SUN Bing zhang jian-wei Sarosh Ali School of Astronautics Beijing University of Aeronautics and Astronautics

The modulus of viscoelastic materials varies with excitation ***,during modal analysis of frequency dependent materials,a material evaluation frequency is necessary because stiffness cannot be modified during eigenfrequency *** a result,only those vibration modes are accurate,of which eigenfrequency is close to the material evaluation *** order to obtain vibration modes of solid rocket motor(SRM) using material modulus based on frequency which is the same as the eigenfrequency,an iterative approach was *** of the iterative technique show that frequency modes obtained from the method are in complete agreement with the eigenfrequency and material evaluation frequency.

关键词： solid rocket motor viscoelastic materials modal analysis eigenfrequency frequency dependent modulus

Soil resource availability impacts microbial response to organic carbon and inorganic nitrogen inputs

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Journal of Environmental Sciences 2005年第5期17卷 705-710页

作者： zhang wei-jian W.ZHU S.HU Department of Agronomy Nanjing Agricultural University Nanjing 210095 China Department of Plant Pathology North Carolina State University Raleigh NC 27605 USA Department of Biological Sciences State University of New YorkBinghamton Binghamton NY 13902 USA

Impacts of newly added organic carbon （C） and inorganic nitrogen （N） on the microbial utilization of soil organic matter are important in determining the future C balance of terrestrial ecosystems. We examined microbial responses to cellulose and ammonium nitrate additions in three soils with very different C and N availability. These soils included an organic soil（ 14.2% total organic C, with extremely high extractable N and low labile C）, a forest soi1（4.7% total organic C, with high labile C and extremely low extractable N）, and a grassland soil（1.6% total organic C, with low extractable N and labile C）. While cellulose addition alone significantly enhanced microbial respiration and biomass C and N in the organic and grassland soils, it accelerated only the microbial respiration in the highly-N limited forest soil. These results indicated that when N was not limited, C addition enhanced soil respiration by stimulating both microbial growth and their metabolic activity, New C inputs lead to elevated C release in all three soils, and the magnitude of the enhancement was higher in the organic and grassland soils than the forest soil. The addition of cellulose plus N to the forest and grassland soils initially increased the microbial biomass and respiration rates, but decreased the rates as time progressed. Compared to cellulose addition alone, cellulose plus N additions increased the total C-released in the grassland soil, but not in the forest soil. The enhancement of total C- released induced by C and N addition was less than 50% of the added-C in the forest soil after 96 d of incubation, in contrast to 87.5% and 89.0% in the organic and grassland soils. These results indicate that indigenous soil C and N availability substantially impacts the allocation of organic C for microbial biomass growth and/or respiration, potentially regulating the turnover rates of the new organic C inputs.

关键词： cellulose inorganic nitrogen microbial biomass microbial activity carbon sequestration

Structural optimization of elliptical-tip star propellant grain using sub-problem approximation

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航空动力学报 2012年第2期27卷 457-464页

作者： Muhammad Adnan SUN Bing zhang jian-wei Ali Sarosh School of Astronautics Beijing University of Aeronautics and AstronauticsBeijing 100191China

A method is presented here for structural optimization of elliptical-tip star *** grain structural integrity was improved by minimizing the most critical area of inner bore hoop strain during cool *** was done by sub-problem approximation method in conjunction with finite element *** radii of the ellipse were varied during optimization to find the optimal *** optimization resulted in grain geometry having minimum level of Inner bore hoop strain without violating the preset limits of burning *** von mises strain at grain inner bore was also reduced in resultant grain.

关键词： solid propellant grain star grain viscoelastic analysis structure optimization sub-problem approximation

A possible mechanism of mineral responses to elevated atmospheric CO_2 in rice grains

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Journal of Integrative Agriculture 2015年第1期14卷 50-57页

作者： GUO Jia zhang Ming-qian WANG Xiao-wen zhang wei-jian Institute of Wetland Research Chinese Academy of Forestry Institute of Applied Ecology Nanjing Agricultural University Technology Center of China Tobacco Fujian Industrial Co. Ltd Chinese Academy of Engineering Institute of Crop Sciences Chinese Academy of Agricultural Sciences/Key Laboratory of Crop EcologyPhysiology & ProductionMinistry of Agriculture

Increasing attentions have been paid to mineral concentration decrease in milled rice grains caused by CO2 enrichment, but the mechanisms still remain unclear. Therefore, mineral （Ca, Mg, Fe, Zn and Mn） translocation in plant-soil system with a FACE （Free-air CO2 enrichment） experiment were investigated in Eastern China after 4-yr operation. Results mainly showed that：（1） elevated CO2 significantly increased the biomass of stem and panicle by 21.9 and 24.0%, respectively, but did not affect the leaf biomass. （2） Elevated CO2 significantly increased the contents of Ca, Mg, Fe, Zn, and Mn in panicle by 61.2, 28.9, 87.0, 36.7, and 66.0%, respectively, and in stem by 13.2, 21.3, 47.2, 91.8, and 25.2%, respectively, but did not affect them in leaf. （3） Elevated CO2 had positive effects on the weight ratio of mineral/biomass in stem and panicle. Our results suggest that elevated CO2 can favor the translocation of Ca, Mg, Fe, Zn, and Mn from soil to stem and panicle. The CO2-led mineral decline in milled rice grains may mainly attribute to the CO2-1ed unbalanced stimulations on the translocations of minerals and carbohydrates from vegetative parts （e.g., leaf, stem, branch and husk） to the grains.

关键词： climate change free-air CO2 enrichment (FACE) hidden hunger nutritional quality paddy field rice

An exo Probe-based Reverse Transcription and Recombinase Polymerase Amplification for Rapid Detection of Feline Calicivirus in Cats

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Biomedical and Environmental Sciences 2024年第3期37卷 325-330页

作者： MU Hong Yun ZHOU Hong Lei JING Zheng LU wei zhang jian wei jiangsu Agri-animal Husbandry Vocational College Taizhou 225300JiangsuChina Boehringer Ingelheim Animal Health(Shanghai)Co. LTD.Shanghai 200040China

Feline calicivirus(FCV)was a highly prevalent RNA virus causing upper respiratory tract infections in cats through the mouth and nose around the world,result in the death of cats especially under 1 year old with upper respiratory tract disease(URTD)and virulent systemic disease(FCV-VSD)[1].Infected cats usually presented with mouth ulcers,salivation and ***,both recovered cats and asymptomatic carriers can still carry and spread the FCV virus for extended periods of time,contributing to the potential for *** presented a significant threat to the health and lives of cats,and rare wildlife and took a heavy financial loss on the pet industry,making the prevention and control of the virus ***,rapid identification of FCV in clinical samples was necessary to prevent the spread of FCV and avoid financial loss.

关键词： prevention respiratory Probe

Total laparoscopic liver resection in 78 patients

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World Journal of Gastroenterology 2009年第45期15卷 5727-5731页

作者： Lei zhang Ya-Jin Chen Chang-Zhen Shang Hong-wei zhang Ze-jian Huang Department of Hepatobiliary Surgery Sun Yat-sen Memorial Hospital Sun Yat-sen University Guangzhou 510120 Guangdong Province China

AIM： To summarize the clinical experience of laparoscopic hepatectomy at a single center. METHODS： Between November 2003 and March 2009, 78 patients with hepatocellular carcinoma （n = 39）, metastatic liver carcinoma （n = 10）, and benign liver neoplasms （n = 29） underwent laparoscopic hepatectomy in our unit. A retrospective analysis was done on the clinical outcomes of the 78 patients. RESULTS： The lesions were located in segments Ⅰ （n = 3）, Ⅱ （n = 16）, Ⅲ （n = 24）, Ⅳ （n = 11）, Ⅴ （n = ii）, Ⅵ （n = 9）, and Ⅷ （n = 4）. The lesion sizes ranged from 0.8 to 15 cm. The number of lesions was three （n = 4）, two （n = 8） and one （n = 66） in the study cohort. The surgical procedures included left hemi-hepatectomy （n = 7）, left lateral lobectomy （n = 14）, segmentectomy （n = 11）, local resection （n = 39）, and resection of metastatic liver lesions during laparoscopic surgery for rectal cancer （n = 7）. Laparoscopic liver resection was successful in all patients, with no conversion to open procedures. Only four patients received blood transfusion （400-800 mL）. There were no perioperative complications, such as bleeding and biliary leakage. The liver function of all patients recovered within 1 wk, and no liver failure occurred. CONCLUSION： Laparoscopic hepatectomy is a safe and feasible operation with minimal surgical trauma. It should be performed by a surgeon with sufficient experience in open hepatic resection and who is proficient in laparoscopy.

关键词： Hepatectomy Laparoscopy Liver neoplasms

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微生物菌群调控人畜共患结核病的研究进展

动物医学进展 2025年第1期46卷 91-96页

作者：许霄峰张广智鑫婷叶建新张建伟贾丽钱佳豪温贺飞吴慧光蒋卉丁家波中国农业科学院北京畜牧兽医研究所北京100097 农业农村部动物生物安全风险预警及防控重点实验室(北方) 北京100193 扬州大学兽医学院江苏扬州225009 北京市畜牧总站北京100193 河北农业大学动物医学院河北保定071000 河北省遵化市农业农村局河北唐山064200

目前,人畜共患结核病(zTB)仍是世界上最重要的细菌传染性疫病之一,严重威胁人和动物健康以及公共卫生安全。机体数量庞大的微生物菌群积极参与着机体的发育、免疫调控、代谢等。研究发现微生物菌群和zTB的发生、发展、治疗、疫苗免疫具... 详细信息

目前,人畜共患结核病(zTB)仍是世界上最重要的细菌传染性疫病之一,严重威胁人和动物健康以及公共卫生安全。机体数量庞大的微生物菌群积极参与着机体的发育、免疫调控、代谢等。研究发现微生物菌群和zTB的发生、发展、治疗、疫苗免疫具有紧密的相关性,现已成为诸多领域中的研究热点。菌群对zTB进程的调控可通过诸多途径直接或间接地进行,如菌群稳态、代谢物及对免疫的调控等。基于此,论文综述了目前微生物菌群与zTB相关研究的最新进展,重点讨论了肠道菌群和肺部菌群与zTB的关联及调节机制,分析了肠-肺轴相互作用、菌群代谢产物对zTB的影响,探讨了通过调节宿主的菌群组成和功能对预防和辅助治疗结核病的潜在价值,旨在为zTB防控提供理论基础和借鉴。

关键词：人畜共患结核病肠道微生物菌群肠-肺轴益生菌

Microstructure and Properties of Hot Rolled Ti-23Al-17Nb Alloy Sheets

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Journal of Iron and Steel Research International 2010年第9期17卷 64-68页

作者： zhang jian-wei LIANG Xiao-bo CHENG Yun-jun LI Shi-qiong Central Iron and Steel Research Institute Beijing 100081 China

Microstructure and tensile properties of Ti-23Al-17Nb （at%） alloy sheets rolled in （a2 ＋ B2 ＋ O） phase field with the various heat treatments were studied. Before rolling the microstructure of the billet is B2 phase particles embedded in O phase continuity matrix. The B2 phases are deformed more greatly than a2/O phases during the same rolling step. The （a2 ＋B2） two phase equiaxed microstrueture can be obtained by solution treatment in （a2 ＋ B2） phase field. The B2 phases become the continuous matrix by recrystallization and growing up of B2 and thus anisotropy caused by rolling can be decreased. The microstructure obtained by solution treatment has better tensile properties than the microstructure gained by subsequent aging treatment in （O＋ B2） phase field because the O phases precipitate as the block structure during aging and results in the B2 matrix continuity being broken down.

关键词： Ti-23Al-27Nb rolled sheet microstructure property