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Observation of the Turbulent Burst near ASheared Air-Water Interface

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Communications in Nonlinear Science and Numerical Simulation 1999年第2期4卷 94-99页

作者： Shuangfeng WANG Fu JIA Zhennan NIU Zhangzhi WU(Institute of Mechanics, Chinese Academy of Sciences, Beijing 100080, China)(state Key laboratory for Turbulence research, Peking university, Beijing 100871,China) Institute of Mechanics Chinese Academy of Sciences Beijing 100080 China

The turbulent burst under a sheared air-water interface was experimentally investigated using hydrogen bubble visualization technique. The surface shear wasimposed by an airflow over the water flow which was kept free from surface waves. Resultsshow that the wind shear has the main influence on the bursting events. At relativelyhigh shear rates, the flow near the interface is dominated primarily by intermittent bursting events. The general features of bursting processes are described in some detail. Theobserved bursting events show qualitative similarities with those occurring in near-wallturbulence. However, a few distinctive phenomena were also observed, including the existence of vertical vortices and thickening process of the boundary layer, which appear tobe associated with the Characteristics of air-water interface.

关键词： air-water interface turbulent burst flow-visualization

Hydrogen metabolic pathways of Rhodospirillum rubrum under artificial illumination

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Chinese Science Bulletin 2010年第1期55卷 32-37页

作者： ZHU RuiYan1,2,3 & LI JiLun1 1 College of Biological Sciences, state Key laboratory for Agrobiotechnology, China Agricultural university, Beijing 100193, China 2 College of Environmental and Chemical Engineering, Yanshan university, Qinhuangdao 066004, China 3 Engineering research Center for Bioenergy of Hebei Province, Qinhuangdao 066004, China College of Biological Sciences State Key Laboratory for Agrobiotechnology China Agricultural University Beijing China College of Environmental and Chemical Engineering Yanshan University Qinhuangdao China Engineering research Center for Bioenergy of Hebei Province Qinhuangdao China

Multiple enzymes involved in hydrogen metabolism have been detected in photosynthetic bacterium Rhodospirillum rubrum un-der various growth conditions. To investigate hydrogen metabolic pathways and the contribution of each pathway to hydrogen photoproduction in R. rubrum under the artificial illumination condition, three mutants were constructed, including nifHanfDG double mutant lacking both Fe-nitrogenase and Mo-nitrogenase, anfDG mutant lacking Fe-nitrogenase and nifHhupL double mu-tant (uptake hydrogenase deficient mutant). Comparison of the hydrogen production of these 3 mutants with R. rubrum wild type and the uptake hydrogenase deficient mutant showed that there was a third pathway involved in hydrogen production besides Mo-nitrogenase and Fe-nitrogenase, which mainly contributed to hydrogen evolution. Only a small portion of hydrogen was gen-erated by the third pathway. The hydrogen produced by Mo-nitrogenase, Fe-nitrogenase and the third pathway was about 93.5%, 4.9% and 1.5%, respectively, while the hydrogen consumed by uptake hydrogenase was about 13.3%. The investigation of the formate-linked hydrogenase activity indicated that the third pathway for hydrogen production was not mediated by the for-mate-linked hydrogenase, but probably by some unknown enzyme.

关键词：氢代谢人工照明代谢途径红螺菌固氮酶脱氢酶突变体体吸收

Advances of multiplex and high throughput biomolecular detection technologies based on encoding microparticles

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Science China Chemistry 2011年第8期54卷 1185-1201页

作者： ZHAO XiangWei, ZHAO YuanJin & GU ZhongZe state Key laboratory of Bioelectronics Southeast university, Nanjing 210096, China state Key laboratory of Bioelectronics Southeast University Nanjing 210096 China.

The rapid developments of genomics and proteomics have driven the demand for multiplex and high throughput analysis of large numbers of biomolecules in the fields of medical diagnostics, drug discovery, and environmental monitoring. Encoding the biomolecular binding events is the key technique to fulfill this demand, in which microparticles play the most important roles. This review outlines the development of multiplex and high throughput biodetections, and highlights the most recent advances in the field of encoding microparticles, together with problems that need to be resolved.

关键词： multiplex bioassays multiplex labels encoded microcarrier binding assays high throughput screening

Black-box testing based on colorful taint analysis

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Science China(Information Sciences) 2012年第1期55卷 171-183页

作者： CHEN Kai1,2,3,FENG DengGuo1,SU PuRui1&ZHANG YingJun1,2,3 1state Key laboratory of Information Security,Institute of Software,Chinese Academy of Science,Beijing 100190,China 2state Key laboratory of Information Security,Graduate university of Chinese Academy of Sciences,Beijing 100049,China 3National Engineering research Center of Information Security,Beijing 100190,China state Key laboratory of Information Security Institute of Software Chinese Academy of Science Beijing China state Key laboratory of Information Security Graduate University of Chinese Academy of Sciences Beijing China National Engineering research Center of Information Security Beijing China

Software vulnerability detection is one of the most important methods for guaranteeing software *** main classes of methods can detect vulnerabilities in binary files:white-box testing and black-box *** former needs to construct and solve path constraints to detect *** has two main drawbacks:path exploding and complexity of *** latter often aimlessly exhausts various inputs to test binary *** paper combines both testing methods to detect vulnerabilities in binary *** analyzing the input elements that aect check condition corresponding to a certain check point,we can generate one class of inputs that get to the check point to increase fuzzing *** analyzing the relationship between guard conditions and check condition,the redundant check points are *** taint analysis method(CTAM)is proposed to compute guard conditions,which is more ecient than traditional taint analysis method(TTAM).We implemented a prototype and made several experiments on *** results showed that our method could increase the eciency of black-box testing.

关键词： software testing vulnerability detection dynamic testing black-box testing colorful taint analysis

A computational trust model for access control in P2P

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Science China(Information Sciences) 2010年第5期53卷 896-910页

作者： LANG Bo state Key laboratory of Software Development Environment, Beihang university, Beijing 100191, China state Key laboratory of Software Development Environment Beihang University Beijing China

Trust brings a new method for building scalable and fine-grained access control mechanism in P2P systems. The quantificational expression of trust and the calculation of trust in a trust network are the basis of trust degree based access control. In this paper, the properties of trust is analyzed by referring to the fruits from social science; the semantics of trust in the context of access control is described, and a trust degree based access control model named TDBAC is introduced. Basing on the properties and semantics of trust, a computational trust model which includes a multilevel comprehensive evaluation method for expressing direct trust and calculators for computing recommended trust is put forward. To compute trust in a trust network, an algorithm that transforms a trust network to a computable expression is given. The algorithm simplifies the computation process and is also flexible.

关键词： trust management access control trust degree based access control computational trust model trust graph expression

Free Radicals in Organic Matter for Thermal History Reconstruction of Carbonate Succession

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Acta Geologica Sinica(English Edition) 2007年第4期81卷 605-613页

作者： QIU Nansheng LI Huili JIN Zhijun and ZHU Yinkang 1 state Key laboratory of Petroleum Resource and Prospecting,China university of Petroleum,Beijing 102249 2 Basin and Reservoir research Center,China university of Petroleum,Beijing 102249 3 Institute of Petroleum Exploration and Development,SINOPEC,Beijing 100083 China Univ Petr State Key Lab Petroleum Resource & Prospecting Beijing 102249 Peoples R China China Univ Petr Basin Reservoir Res Ctr Beijing 102249 Peoples R China SINOPEC Inst Petr Explorat & Dev Beijing 100083 Peoples R China

Geothermometer is one of the most useful methods to reconstruct the thermal history of sedimentary basins. This paper introduces the application of free radicals concentration of organic matter as a thermal indicator in the thermal history reconstruction of carbonate succession, based on anhydrous thermal simulation results of type I and H1 kerogen. A series of free radicals data are obtained under thermal simulation of different heating temperatures and times, and quantitative modds between free radical concentration （Ng） of organic matter and time-temperature index （TTI） for types I and type H1 kerogen are also obtained. This *** relation was used to model the Ordovician thermal gradients of Well TZ12 in the Tarim Basin. The modeling result is corresponding to the results obtained by apatite fission track data and published data. This new method of thermal history reconstruction will be benefit to the hydrocarbon generation and accumulation study and resource assessment of carbonate succession.

关键词： carbonate succession geothermometer free radicals of organic matter apatite fission track thermal history

EXPERIMENTAL　research　ON　DIRECTIONAL　SOLIDIFICATION　OF　Al－4．5wt％Cu　ALLOY　BY　ACRT　METHOD

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Acta Metallurgica Sinica(English Letters) 1996年第1期9卷 17-22页

作者： JIE Wanqi(state Key laboratory of Solidification Processing,Northwestern Polytechnical university,Xi’an 710072,China) Northwestern Polytechnical Univ Xi'an China

Accelerated crucible rotation technique(ACRT) has been used for the directional solidification of Al-4.5wt% Cu binary *** rotating the crucible at varying rate and direction,forced liquid flows are aroused These flows include Ekman flow,Couette flow and Spiral Shear ***,Ekman flow acts directly at the L/S interface,changes diffusion and heat exchange conditions and has strong influences on the morphology of L/S *** results show that,compared with normal Bridgman specimens,the solidification region is much narrower and the cell spacing is much smaller in ACRT *** influences become much stronger when the accelerating rate is increased.

关键词： accelerated crucible rotation technique(ACRT) Al-4.5wt%Cu directional solidification morphology of L/S interface cell spacing

METHODS OF MODERN DESIGN FOR CYLINDRICAL GEAR DRIVE BASED ON THE INTERNET

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Chinese Journal of Mechanical Engineering 2002年第1期15卷 62-65页

作者： Lin Chao Li Runfang state Key laboratory of Mechanical Transmission，Chongqing university， Chongqing 400044，China Chongqing university State Key Laboratory of Mechanical Transmission 重庆 400044

The basic principle of modern design of cylindrical gear drive based on theInternet is described. The methods of optimized design, finite element analysis, CAD design and webdesign as well as research and development entity of three parties such as institute research unit(or university), enterprise and customer are also studied. Its purpose is to provide a necessaryfoundation for realizing the design of cylindrical gear drive from different location on the modemInternet and to explore a practice application route.

关键词： Internet Cylindrical gear Mechanical model

A UNIFIED TIME-MARCHING PROCEDURE FOR COMPRESSIBLE INCOMPRESSIBLE FLOWS

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Journal of Hydrodynamics 1995年第4期7卷 13-21页

作者： Charles L. Merkle Feng Jin-zhang(Propulsion Engineering research, The Pennsylvania state university, university Park, PA 16802, USA) The Pennsylvania state Univ United States

A time derivative preconditioning is introduced that allows a unified treatment of timemarching methods for both compressible and incompressible flows from inviscid to creeping flow. Results show that convergence rates are independent of Reynolds numbers and Mach numbers throughout this regime. A Complete formulation'based on an arbitrary equation of state facilitates the changes from one type of fluid to another and, in particular, the extension to incompressible flows. The resulting time-marching algorithm is shown in the incompressible limit to be identical to iterative methods based on pressure-Poisson methods, and it is demonstrated that both method are hyperbolic.

关键词： computational fluid dynamics time-marching procedure flow