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期刊论文 7

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2019 1

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压裂 1

微地震监测 1

裂缝 1

钢管复合桩;埋床法预制墩台;?75 mm预应力粗钢筋;正交异性钢桥面板;1 860 MPa斜拉索; 减隔震 1

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Numerical investigation of the effectiveness of effusion cooling for plane multi-layer systems with different base-materials

Dieter BOHN, Robert KREWINKEL

《能源前沿(英文)》 2009年 第3卷 第4期   页码 406-413 doi: 10.1007/s11708-009-0041-x

摘要: Within Collaborative Research Center (SFB) 561 “Thermally Highly Loaded, Porous and Cooled Multi-Layer Systems for Combined Cycle Power Plants” at RWTH Aachen University, an effusion-cooled multi-layer plate configuration is investigated numerically by the application of a three-dimensional in-house fluid flow and heat transfer solver, CHTflow. CHTflow is a conjugate code, which yields information on the temperature distribution in the solid body. This enables a detailed discussion of the effects of a change in materials. The geometrical set-up and the fluid flow conditions derive from modern gas turbine combustion chambers and bladings. Within the SFB, two different multi-layer systems, one consisting of substrate made of CMSX-4 (a single-crystal super-alloy), an MCrAlY-bondoat and a ZrO thermal barrier coating (TBC), and the other consisting of a NiAl-alloy and a graded bondcoat/TBC, have been investigated. The grading will increase the life-span of the TBC as it can better compensate the different thermal expansion coefficients of different materials. The main focus in this study is on the different substrate materials, because the thermal conductivity of the NiAl is considerably higher than that of CMSX-4, which leads to different temperature profiles in the components. The numerical grid for the simulations contains the coolant supply (plenum), the solid body for the conjugate calculations, and the main flow area on the plate. The effusion-cooling is realized by finest drilled shaped holes with a diameter of 0.2mm. The investigation is concentrated on a cooling hole geometry with a laterally widened fan-shaped outlet, contoured throughout, and one without lateral widening that is only shaped in the TBC-region of the system. Two blowing ratios, =0.28 and =0.48, are investigated, both for a hot gas Mach number of 0.25. The results for the lower blowing ratio and the fully contoured hole are discussed as well as those of the higher blowing ratio and the non-laterally widened hole. These represent two characteristic cases.

关键词: conjugate calculation     effectiveness of effusion cooling     multi-layer systems     CMSX-4     NiAl-FG75    

Characterization of Bacillus amyloliquefacien contaminating 75% alcohol disinfectant

ZHANG Wanming, YUAN Yuesha, BIAN Cangli, TU Xianyu, ZHANG Wen, HUANG Huqiang, WANG Lan

《医学前沿(英文)》 2008年 第2卷 第1期   页码 113-116 doi: 10.1007/s11684-008-0021-2

摘要: The clinical characterization of Bacillus amyloliquefacien contaminating 75% alcohol disinfectants were studied. The bacteria were cultured and observed by using bacterial examination under the hospital infection monitor. According to the regulations, the resistance of bacterial to physical and chemical factors was tested. Drug sensitivity tests for 20 commonly used medicines were carried out using a K-B method. The bacterial plasmids were analyzed using the Birnboim method. The bacteria were found after being cultured in the clinically-used 75% alcohol disinfectant fluid. Their total number was more than 800 cfu/mL and they were identified as Bacillus amyloliquefacien. The bacteria were also found to be resistant to boiling for 5 min. It grew well in 95% alcohol disinfectant and was insensitive to 84 disinfectant fluids containing chlorine (1000 mg/L) and such disinfectants as ozone. They were able to be sterilized better through routine ultraviolet exposure for 30 min or gas pressure. The bacteria contained a 2.5 kb plasmid and were sensitive to 13 drugs and insensitive to 7 drugs of the 20 drugs tested. It was suggested that alcohol disinfectant fluid was easily contaminated by Bacillus amyloliquefacien, and the bacteria was resistant to disinfectant fluids such as alcohol and 84 disinfectants

Free vibration analysis of laminated FG-CNT reinforced composite beams using finite element method

T. VO-DUY, V. HO-HUU, T. NGUYEN-THOI

《结构与土木工程前沿(英文)》 2019年 第13卷 第2期   页码 324-336 doi: 10.1007/s11709-018-0466-6

摘要: In the present study, the free vibration of laminated functionally graded carbon nanotube reinforced composite beams is analyzed. The laminated beam is made of perfectly bonded carbon nanotubes reinforced composite (CNTRC) layers. In each layer, single-walled carbon nanotubes are assumed to be uniformly distributed (UD) or functionally graded (FG) distributed along the thickness direction. Effective material properties of the two-phase composites, a mixture of carbon nanotubes (CNTs) and an isotropic polymer, are calculated using the extended rule of mixture. The first-order shear deformation theory is used to formulate a governing equation for predicting free vibration of laminated functionally graded carbon nanotubes reinforced composite (FG-CNTRC) beams. The governing equation is solved by the finite element method with various boundary conditions. Several numerical tests are performed to investigate the influence of the CNTs volume fractions, CNTs distributions, CNTs orientation angles, boundary conditions, length-to-thickness ratios and the numbers of layers on the frequencies of the laminated FG-CNTRC beams. Moreover, a laminated composite beam combined by various distribution types of CNTs is also studied.

关键词: free vibration analysis     laminated FG-CNTRC beam     finite element method     first-order shear deformation theory     composite material    

祼孔长水平井苏75-70-6H连续压裂微地震监测

王万迅,叶连池,王立治,段正中

《中国工程科学》 2012年 第14卷 第4期   页码 4-7

摘要:

75-70-6H井是依靠国产技术完成的规模最大的裸孔水平井压裂井,水平段南北走向。

关键词: 压裂     微地震监测     裂缝    

港珠澳大桥设计理念及桥梁创新技术

孟凡超,刘明虎,吴伟胜,张革军,张 梁

《中国工程科学》 2015年 第17卷 第1期   页码 27-35

摘要:

介绍了港珠澳大桥的工程概况、建设目标和总体设计方案,重点阐述了以“大型化、工厂化、标准化、装配化”的设计理念和总体原则指导下,设计采用的新材料、新技术、新工艺、新设备。创新技术的应用,为提高工程品质、确保设计使用寿命提供了坚实基础和有利保障。

关键词: 75 mm预应力粗钢筋;正交异性钢桥面板;1 860 MPa斜拉索; 减隔震    

Nonlinear dynamic analysis of functionally graded carbon nanotube-reinforced composite plates using MISQ20 element

《结构与土木工程前沿(英文)》   页码 1072-1085 doi: 10.1007/s11709-023-0951-4

摘要: The main objective of this study is to further extend the mixed integration smoothed quadrilateral element with 20 unknowns of displacement (MISQ20) to investigate the nonlinear dynamic responses of functionally graded carbon nanotube-reinforced composite (FG-CNTRC) plates with four types of carbon nanotube distributions. The smooth finite element method is used to enhance the accuracy of the Q4 element and avoid shear locking without using any shear correction factors. This method yields accurate results even if the element exhibits a concave quadrilateral shape and reduces the error when the element meshing is rough. Additionally, the element stiffness matrix is established by integrating the boundary of the smoothing domains. The motion equation of the FG-CNTRC plates is solved by adapting the Newmark method combined with the Newton–Raphson algorithm. Subsequently, the calculation program is coded in the MATLAB software and verified by comparing it with other published solutions. Finally, the effects of the input parameters on the nonlinear vibration of the plates are investigated.

关键词: carbon nanotube     MISQ20     FG-CNTRC plate     nonlinear vibration     nonlinear dynamic analysis     SFEM    

Difference between 2 h and 3 h 75 g glucose tolerance test in the diagnosis of gestational diabetes mellitus

Xue-Lian GAO, Yu-Mei WEI, Hui-Xia YANG, Xian-Ming XU, Ling FAN, Jing HE, Ning LIU, San-Cun ZHAO, Ya-Li HU, Zi YANG, Yun-Ping ZHANG, Xing-Hui LIU, Xu CHEN, Jian-Ping ZHANG, Wen-Li GOU, Mei XIAO, Hai-Rong WU, Mei-Hua ZHANG

《医学前沿(英文)》 2010年 第4卷 第3期   页码 303-307 doi: 10.1007/s11684-010-0090-x

摘要: The possibility of the 2 h oral glucose tolerance test (OGTT) as an alternative to the 3 h OGTT was investigated based on data from a national survey on pregnancy-associated diabetes. Data were retrieved from 4179 pregnant women who had OGTT performed after an abnormal 50 g glucose challenge test (GCT). All of the 4 glucose levels during their OGTT were collected and analyzed. According to American Diabetes Association (ADA) gestational diabetes mellitus (GDM) diagnostic criteria, among the 4179 pregnant women who required OGTT, 3429 (82.1%) were normal and 750 (17.9%) were diagnosed as GDM. If the 3rd h glucose levels were omitted from OGTT, 79 cases of GDM (10.5%) would be overlooked. No trend was shown where women with more risk factors were more likely to be overlooked if the 3rd h test was omitted ( for trend= 0.038, >0.05). No significant differences were found in the rate of cesarean section (CS), preterm births or macrosomia between the 79 cases and those with normal OGTT results and in the gestational weeks when OGTT was performed. It shows that in order to diagnose one woman with GDM, another 52 pregnant women would have an innocent 3rd h glucose test. Omission of the 3rd h glucose test in OGTT might be reasonable due to its convenience, better compliance and a small number of possibly miss-diagnosed cases, and their pregnancy outcomes have no significant difference from those of normal pregnant women.

关键词: diabetes     gestational     oral glucose tolerance test    

标题 作者 时间 类型 操作

Numerical investigation of the effectiveness of effusion cooling for plane multi-layer systems with different base-materials

Dieter BOHN, Robert KREWINKEL

期刊论文

Characterization of Bacillus amyloliquefacien contaminating 75% alcohol disinfectant

ZHANG Wanming, YUAN Yuesha, BIAN Cangli, TU Xianyu, ZHANG Wen, HUANG Huqiang, WANG Lan

期刊论文

Free vibration analysis of laminated FG-CNT reinforced composite beams using finite element method

T. VO-DUY, V. HO-HUU, T. NGUYEN-THOI

期刊论文

祼孔长水平井苏75-70-6H连续压裂微地震监测

王万迅,叶连池,王立治,段正中

期刊论文

港珠澳大桥设计理念及桥梁创新技术

孟凡超,刘明虎,吴伟胜,张革军,张 梁

期刊论文

Nonlinear dynamic analysis of functionally graded carbon nanotube-reinforced composite plates using MISQ20 element

期刊论文

Difference between 2 h and 3 h 75 g glucose tolerance test in the diagnosis of gestational diabetes mellitus

Xue-Lian GAO, Yu-Mei WEI, Hui-Xia YANG, Xian-Ming XU, Ling FAN, Jing HE, Ning LIU, San-Cun ZHAO, Ya-Li HU, Zi YANG, Yun-Ping ZHANG, Xing-Hui LIU, Xu CHEN, Jian-Ping ZHANG, Wen-Li GOU, Mei XIAO, Hai-Rong WU, Mei-Hua ZHANG

期刊论文