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Journal of Environmental sciences 1994年第2期6卷 200-205页

作者： Bao Ziping He Jianquan Hou Fuzhong(Institute of Environmental sciences, beijing {3.mial University, beijing 100875, china)

Edible oils-rapeseed oil, soybean oil and peanut oil are heated in air at 270-280 ℃respectively. The volatile condensates are collected and analyzed by means of GC/MS. Eithercrotonaldehyde or 2-methylacrolein is found respectively in the condensates of rapeseed oil andsoybean oil. Neither crotonaldehyde {3. 2-methylacrolein is found in the condensates of peanut *** of formation of crotonaldehyde is discussed.

关键词： edible oils volatile condensates mutagens crotonaldehyde 2-methylacrolein.

The precipitation and effect of nano nitrides in HSLC steel

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Science china(Technological sciences) 2008年第7期51卷 989-998页

作者： FU Jie1, LIU YangChun1,2 & WU HuaJie1,3.1 school of Metallurgical and Ecological Engineering, University of Science and Technology beijing, beijing 100083. china 2 Shougang Technology Research Institute, Shougang (Group) Corporation, beijing 100041, china 3.Metallurgical Engineering Research Institute, University of Science and Technology beijing, beijing 100083. china school of Metallurgical and Ecological Engineering University of Science and Technology Beijing Beijing China Shougang Technology Research Institute Shougang (Group) Corporation Beijing China Metallurgical Engineering Research Institute University of Science and Technology Beijing Beijing China

The existing forms of N and al in HSLC (high strength low carbon) steel produced by TSCR (thin slab casting and rolling process), the precipitation thermodynamics and kinetics of alN, and its effects on structure and mechanical property are studied. The experimental results show that only a small quantity of nitrogen is com- bined into alN in HSLC steel produced by TSCR and most of the nitrogen in steel is still free nitrogen. aluminum-nitride is mainly precipitated during the period of slow air cooling after coiling, but not during rolling and water cooling. The acid-soluble aluminum has no obvious effect on the grain size and mechanical property of HSLC steel produced by TSCR whose acid-soluble aluminum content is 0.005%―0.043.. The precipitation of alN is not the main cause of grain refinement of HSLC steel produced by TSCR, nor is alN the dominating precipitate that has precipitation strengthening effect. The nano nitrides are not pure alN, but have complex compositions.

关键词： thin slab casting and rolling high strength low carbon steel alN nano nitride precipitation strengthening

Large field of view computed laminography with the asymmetric rotational scanning geometry

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Science china(Technological sciences) 2010年第8期53卷 2261-2271页

作者： FU Jian 1,2 ,JIANG BaiHong&LI Bin 1 school of Mechanical Engineering and Automation,Beihang University,beijing 100191,{3. 2 Research Center of Digital Radiation Imaging and Biomedical Imaging,Beihang University,beijing 100191,{3. school of Mechanical Engineering and Automation Beihang University Beijing China Research Center of Digital Radiation Imaging and Biomedical Imaging Beihang University Beijing China

X-ray computed laminography(CL)is used in the fields of industrial inspection and medical *** can provide the internal structure three-dimensional(3.)information of a region of the objects *** is important to the clinical diagnosis and the quality control of flat objects like printed circuit boards,aircraft wings and satellite solar *** the restriction that the imaging region must be within the X-ray beam formed by the X-ray source and the detector,the imaging field of view of CL is limited by the size of detector.A new CL method with an asymmetric rotational cone-beam scanning geometry,called large field of view CL,is presented to overcome the existing *** can extend the imaging region when the imaging spatial resolution keeps the same as that of the conventional *** can also improve the imaging spatial resolution when the imaging region keeps the same as that of the conventional *** asymmetric configuration can be achieved by offsetting the detector from the conventional symmetric *** does not,however,require new detectors and X-ray source nor.alter the scanning mechanical *** filtered back-projection(FBP)reconstruction algorithm and the data truncation smoothing functions have been deduced to reconstruct the images directly from the data acquired with this asymmetric *** performed numerical studies and experiments to demonstrate and validate the proposed approach. Results in these studies and experiments confirm that the proposed method can enlarge the imaging region and improve the spatial *** proposed approach may find applications in the CL system with the rotational scanning geometry.

关键词： computed laminography image reconstruction reconstruction algorithm imaging field of view imaging spatial resolution

A new class of symmetric periodic solutions of the spatial elliptic restricted three-body problem

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Science china(Physics,Mechanics & Astronomy) 2009年第9期52卷 1404-1413页

作者： XU XingBo1,2 & FU YanNing1 1 Purple Mountain Observatory, Chinese Academy of sciences, Nanjing 210008, china 2 Graduate University of Chinese Academy of sciences, {3. 10003., china Purple Mountain Observatory Chinese Academy of Sciences Nanjing China Graduate University of Chinese Academy of sciences Beijing China

We show that there exists a new class of symmetric periodic solutions of the spatial elliptic restricted three-body problem. In such a solution, the infinitesimal body is confined to the vicinity of a primary and moves on a nearly circular orbit. This orbit is almost perpendicular to the orbital plane of the primaries, where the line of symmetry of the orbit lies. The existence is shown by applying a corollary of Arenstorf's fixed point theorem to a periodicity equation system of the problem. And this existence doesn't require any restriction on the mass ratio of the primaries, nor on the eccentricity of their relative elliptic orbit. Potential relevance of this new class of periodic solutions to real celestial body systems and the follow-up studies in this respect are also discussed.

关键词： periodic orbits spatial restricted three-body problem symmetric orbits averaging

Hierarchical linear regression models for conditional quantiles

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Science china Mathematics 2006年第12期49卷 1800-1815页

作者： TIAN Maozai & CHEN Gemai school of Statistics, Renmin University of china, beijing 100872, china and Center for Applied Statistics, Renmin University of china, beijing 100872, china Department of Mathematics and Statistics, University of Calgary, Canada school of Statistics Renmin University of China Beijing China Center for Applied Statistics Renmin University of China Beijing China Department of Mathematics and Statistics University of Calgary Canada

The quantile regression has several useful features and therefore is gradually developing into a comprehensive approach to the statistical analysis of linear and nonlinear response models,but it cannot deal effectively with the data with a hierarchical *** practice,the existence of such data hierarchies is neither accidental nor ignorable,it is a common *** ignore this hierarchical data structure risks overlooking the importance of group effects,and may also render many of the traditional statistical analysis techniques used for studying data relationships *** the other hand,the hierarchical models take a hierarchical data structure into account and have also many applications in statistics,ranging from overdispersion to constructing min-max ***,the hierarchical models are virtually the mean regression,therefore,they cannot be used to characterize the entire conditional distribution of a dependent variable given high-dimensional ***,the estimated coefficient vector (marginal effects)is sensitive to an outlier observation on the dependent *** this article,a new approach,which is based on the Gauss-Seidel iteration and taking a full advantage of the quantile regression and hierarchical models,is *** the theoretical front,we also consider the asymptotic properties of the new method,obtaining the simple conditions for an n1/2-convergence and an asymptotic *** also illustrate the use of the technique with the real educational data which is hierarchical and how the results can be explained.

关键词： hierarchical quantile regression models,EQ algorithm,fixed effects,random effects,regression quantile.

Adaptive RBF neural network control of robot with actuator nonlinearities

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控制理论与应用（英文版） 2010年第2期8卷 249-256页

作者： Jinkun LIU, Yu LU (school of Automation Science and Electrical Engineering, beijing University of Aeronautics and Astronautics, beijing 100191, china) school of Automation Science and Electrical Engineering Beijing University of Aeronautics and Astronautics Beijing China

In this paper, an adaptive neural network control scheme for robot manipulators with actuator nonlinearities is presented. The control scheme consists of an adaptive neural network controller and an actuator nonlinearities compensator. Since the actuator nonlinearities are usually included in the robot driving motor, a compensator using radial basis function (RBF) network is proposed to estimate the actuator nonlinearities and eliminate their effects. Subsequently, an adaptive neural network controller that neither requires the evaluation of inverse dynamical model nor the time-consuming training process is given. In addition, GL matrix and its product operator are introduced to help prove the stability of the closed control system. Considering the adaptive neural network controller and the RBF network compensator as the whole control scheme, the closed-loop system is proved to be uniformly ultimately bounded (UUB). The whole scheme provides a general procedure to control the robot manipulators with actuator nonlinearities. Simulation results verify the effectiveness of the designed scheme and the theoretical discussion.

关键词： Adaptive control RBF neural network Actuator nonlinearity Robot manipulator Deadzone

Dry electrode for the measurement of biopotential signals

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Science china(Information sciences) 2011年第11期54卷 2435-2442页

作者： WANG Yu 1,2,PEI WeiHua 2,GUO Kai 2,GUI Qiang 2,LI XiaoQian 2,CHEN HongDa 2 & YANG JianHong 11 Institute of Microelectronics,school of Physical Science and Technology,Lanzhou University Lanzhou 73.000,china 2 State Key Laboratory on Integrated Optoelectronics,Institute of Semiconductors,Chinese Academy of {3.,beijing 100083.china Institute of Microelectronics School of Physical Science and Technology Lanzhou University Lanzhou China State Key Laboratory on Integrated Optoelectronics Institute of Semiconductors Chinese Academy of Sciences Beijing China

This paper introduces a kind of silicon-based dry electrode for measuring biological *** uses microneedle arrays to penetrate into the stratum corneum to reduce skin *** dry electrode requires neither skin preparation nor the electrolytic gel,is easy to use and causes no skin *** different technologies are chosen to manufacture microneedle arrays of dry *** is deep dry etching combined with isotropic wet *** other is mechanical dicing combined with chemical wet etching (including isotropic wet etching and anisotropic wet etching).Microneedle arrays are coated with metal and divided into 25 mm 2 as dry electrode *** testing shows that the impedance value of dry electrode can be comparable with that of commercial electrode in the 20 Hz-10 kHz frequency *** steady-state visual evoked potential recording and analysis prove that the dry electrode can be used to detect electroencephalography.

关键词： dry electrode microneedle array dry etching wet etching EEG

Designing Drill-in Fluids by Using Ideal Packing Technique

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Petroleum Science 2007年第2期4卷 44-51页

作者： Feng Wenqiang and Yan Jienian (school of Petroleum Engineering, china University of Petroleum, beijing 102249, china) china Univ Petr Sch Petr Engn Beijing 102249 Peoples R China

Selecting bridging agents properly is a critical factor in designing non-damaging or low-damaging drill-in fluids. Historically, Abrams' rule has been used for this purpose. However, Abrams' rule only addresses the size of particle required to initiate a bridge. The rule does not give an optimum size nor an ideal packing sequence for minimizing fluid invasion and optimizing sealing. This paper elaborates an ideal packing approach to solving the sealing problem by sealing pores with different sizes, especially those large pores which usually make dominant contribution to permeability and thereby effectively preventing the solids and filtrate of drill-in fluids from invading into formations, compared with the conventionally used techniques. Practical software has been developed to optimize the blending proportion of several bridging agents, so as to achieve ideal packing effectiveness. The method and its use in selecting the best blending proportion of several bridging agents are also discussed in this paper. A carefully designed drill-in fluid by using the ideal packing technique (named the IPT fluid) for offshore drilling operations at the Weizhou Oilfield, Nanhai West Company, CNOOC is presented. The near 100% return permeabilities from the dynamic damage tests using reservoir cores demonstrated the excellent bridging effect provided by this drill-in fluid.

关键词： Drill-in fluid particle size distribution ideal packing theory dynamic damage test formation damage control

Functional remodeling of Ca^(2+)-activated Cl^-channel in pacing induced canine failing heart

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Journal of Geriatric Cardiology 2008年第3期5卷 169-174页

作者： Ning Li,~1 Kejuan Ma,~2 Siyong Teng,~2 Jonathan C.Makielski,~3.Jielin Pu~(1,2) 1. Research Center for Pathology and Physiology, Fu Wai Cardiovascular Hospital, Chinese Academy of Medical sciences and Peking Union Medical College, beijing 10003., china 2. Center for Arrhythmia Diagnosis and Treatment, Fu Wai Cardiovascular Hospital, Chinese Academy of Medical sciences and Peking Union Medical College, beijing 10003., china 3. Department of Cardiology, University of wisconsin, Madison 53.06, USA Research Center for Pathology and Physiology Fu Wai Cardiovascular Hospital Chinese Academy of Medical Sciences Beijing 100037 China Center for Arrhythmia Diagnosis and Treatment Fu Wai Cardiovascular Hospital Chinese Academy of Medical Sciences Beijing 100037 China Department of Cardiology University of Wisconsin Madison WI 53706 United States

Objective To determine whether Ca2+ activated Cl- current(Icl(Ca)) contributes to the functional remodeling of the failing *** Whole cell patch-clamp recording technique was employed to record the Icl(Ca) in cardiac myocytes enzymatically isolatedfrom rapidly pacing induced canine failing hearts at room temperature and compared that of the nor.al hearts ({3.).Results Thecurrent density of DIDS(200M)sensitive Icl(Ca) induced by intracellular Ca2+ release trigged by L-type Ca2+ current(Ica,L)wassignificantly decreased in heart failare(HE)cells compared to {3. *** membrane voltage of 20mV,the Icl(Ca) density was 3.02±0.54 pA/pF in {3.(n=6)vs.1.3.±0.25 pA/pF in HF(n=8)cells,(P＜0.01),while the averaged Ica,L density did not show differencebetween two *** time constant of current decay of Icl(Ca) was similar in both types of *** the other hand,in intra cellularCa2+ clamped mode,where the[Ca2+];was maintained at 100nmol/L,Icl(Ca) density be increased significantly in HF cells when themembrane voltage at+3.mV or *** Our results suggest that Icl(Ca) density was decreased in pacing induced failingheart but the channel function be *** Ca2+ handing in HF cells rather than reduced,Icl(Ca) channel function itself may havecaused this *** Icl(Ca) density reduction might contribute to the prolongation of action potential in failing *** Icl(Ca)channel function up-rugulation is likely to cause cardiac arrhythmia by inducing a delayed after depolarization,when Ca2+ overloadoccurred in diastolic failing heart cells.

关键词： heart failure cardiac arrhythmia Ca^(2+)-activated Cl^-channel

Biosystematic studies on Adenophora potaninii ***(Campanulaceae) V.A taxonomic treatment

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Journal of Systematics and Evolution 2010年第6期48卷 445-454页

作者： Song GE De-Yuan HONG(State Key Laboratory of Systematic and Evolutionary Botany,Institute of Botany,Chinese Academy of sciences,beijing 100093.china) (State Key Laboratory of Systematic and Evolutionary Botany Institute of Botany Chinese Academy of Sciences Beijing 100093 China)

Adenophora is an extremely variable genus,and its taxonomy is very *** the genus,Adenophora potaninii complex,including ***,***,***,***,***,***,and *** ***,is a typical group with different taxonomical treatments due to high level of morphological *** carried out extensive biosystematic studies based on population sampling,transplantation experiments and offspring tests,cluster analysis,and a crossing *** results reveal four main findings.(i) Leaf forms of the *** complex were extremely polymorphic;the leaf form of *** and ***,and that of *** and *** could be found,respectively,on a single population or among the offsprings of a single plant.(ii) Cluster analysis and a crossing experiment indicated that *** and *** could not be separated from ***,nor *** from ***.(iii) Adenophora potaninii and *** were gradational in morphology and their compatibility value was slightly reduced compared to that within each entity.(iv) Adenophora lobophylla was distinct from the other members of the complex in shape and size of corolla,relative length of style,and shape of *** species was incompatible reproductively with the other members of the complex,but partly compatible with ***,a species in another ***,we recognized only one species with two subspecies in the complex,*** *** and ***,moved *** out of the complex,and reduced all the other names as new synonyms.

关键词： Adenophora potaninii biosystematics populations species complex taxonomy.