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Acta Geologica Sinica(English Edition) 1990年第3期64卷 309-327,344-346+348页

作者： Dong Xiping Department of Geology, peking university, {1. Department of Geology Peking University Beijing

The Middle-Upper Cambrian boundary is one of the current stratigraphical problems which remain openin the geological world, since there have been no universally acknowledged delimiting standard and *** on the instruction of Profs. Lu Yanhao and An Taixiang the author studied in details the Paibi Section,which is well exposed as a continuous sequence at an easily accessible locality. The Middle-Upper Cambrianboundary strata are composed of biocalcimicrosparite, indicating the sedimentary environment of anunderwater upheaval on the gentle slope along the frontal margin of the Yangtze carbonate platform. For the upper Middle and lower Upper Cambrian agnostid trilobite zones and conodont zones are erected,and a more accurate correlation between the trilobite and conodont sequences is established. Based on these,the Middle-Upper Cambrian boundary is drawn more reasonably and precisely than what was done before. Inshort, the section studied is superior to other known sections of Middle-Upper Cambrian. and it will probablybe an ideal candidate for the Middle-Upper Cambrian boundary stratotype.

关键词： In An Introduction to the Paibi Section in Huayuan,Hunan A Potential Candidate For the Middle-Upper Cambrian Boundary Stratotype

Hybrid microsystem with functionalized silicon substrate and PDMS sample operating microchannel: A reconfigurable microfluidics scheme

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Science China(Technological Sciences) 2010年第8期53卷 2272-2277页

作者： LEI YinHua 1.,XIE Fei 1.,WANG Wei 1.2 ,WANG HaiBin 3.&LI ZhiHong 1.2 1.Institute of Microelectronics,{1.,beijing 1.0871.China 2National Key Laboratory of Science and Technology on Micro/Nano Fabrication,beijing 1.0871.China 3.No.3.2 Hospital,beijing 1.003.,China 1. Institute of Microelectronics Peking University Beijing 100871 China2. National Key Laboratory of Science and Technology on Micro/Nano Fabrication Beijing 100871 China3. No. 302 Hospital Beijing 100039 China

A hybrid microsystem with separately functioned temperature controlling substrate and sample operating fluidic microchannel was developed to demonstrate a reconfigurable microfluidics *** temperature controlling substrate integrated a micro heater and a temperature sensor by using traditional silicon-based micromechanical system(MEMS)technique,which guaranteed high performance and robust reliability for repeatable *** sample operating fluidic microchannel was prepared by poly-(dimethylsiloxane) (PDMS)based soft lithography technique,which made it cheap enough for disposable *** PDMS microchannel chip was attached to the temperature controlling substrate for reconfigurable thermal applications.A thin PDMS film was used to seal the microchannel and bridge the functionalized substrate and the sample inside the channel,which facilitated heat transferring and prevented sample contaminating the temperature controlling *** by a one dimensional thermal resistance model,the thin PDMS film was important for the present reconfiguration *** performance of this hybrid microsystem was examined,and the experimental results demonstrated that the chip system could work stably over hours with temperature variation less than *** PDMS microchannel chips were tested on one heating substrate sequentially with a maximum intra-chip temperature difference of *** extracted from serum of a chronic hepatitis B virus(HBV)patient was amplified by this hybrid microsystem and the gel electrophoresis result indicated that the present reconfigurable microfluidic scheme worked successfully.

关键词： reconfigurable microfluidics hybrid microdevice thin PDMS film

Mesozoic-Cenozoic tectonic transition in Kuqa Depression-Tianshan,Northwest China:Evidence from sandstone detrital and geochemical records

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Science China Earth Sciences 2005年第9期48卷 1387-1402页

作者： LI Zhong1. GUO Hong2, WANG Daoxuan3.& LIN Wei1.1. Institute of Geology and Geophysics, Chinese Academy of Sciences, {1. 1.0029, China 2. Tarim Oilfield Branch, CNPC, Korla 841.00, China 3. Hefei university of Industry, Tunxilu 1.3. Hefei 23.009, China 1. Institute of Geology and Geophysics Chinese Academy of Sciences 100029 Beijing Chin 2. Tarim Oilfield Branch CNPC 841000 Korla China 3. Hefei {1. of Industry Tunxilu 193 230009 Hefei Chin

Similar to compositional evolution of sandstone modes and detrital heavy minerals from different profiles in the Kuqa Depression, Northwest China, major element analysis of whole sandstones from the same profiles shows four discontinuous depositional interfaces or periods, respectively corresponding to Lower Triassic\Middle Triassic, Upper Jurassic\Lower Cretaceous, Lower Cretaceous\Paleogene and Miocene\Pliocene, and indicates five-phase evolution during Mesozoic-Cenozoic: (1. From the first to fifth phase, a depositional suite changes from maroon and coarse clastic, through grey-dark grey and fine, red and coarse, red-mottled, interlayered by gypsum, to brown and coarse clastic assemblages, accompanying detrital component evolution in unstable-stable-unstable-very unstable-very unstable assem- blages. It is indicated that carbonate and complex detritus gradually dominate in sandstones in post-Late Jurassic, with rapid reduction of compositional maturity. (2) For major element geo- chemical parameters of whole sandstones, CaO and Fe2 O * 3.MgO contents show a change sequence in high-low-high-higher-highest values, with rapid increasing in post-Late Jurassic. (3. Contra some aggregative indicators for weathering indexes of sandstone detrital component, Al2O3.(CaO+Na2O) and ln(Q/(L+CE)), show a change sequence in low-high-low-lower-lowest ratios, with rapid decreasing in post-Late Jurassic. It is found that sandstone samples of the first, second and later three phases may be distinguished from the A-CN-K and A-CNK-FM diagrams respectively. Therefore, in the Kuqa Depression-Tianshan, the most important discontinuous depositional interface recording paleotectonic and paleoclimatic transition occurred in Early Triassic\Middle Triassic and Late Jurassic\Early Cretaceous, respectively, and, however, tec- tonic differentiations of basin-range system finally result in distinct depositional systems but similar detrital weathering indexes across the Lower Cretaceous\Paleogene

关键词： Tianshan, Kuqa Depression, basin-range, depositional record, tectonic transition, Mesozoic-Cenozoic.

Applications of functionalized ionic liquids

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Science China Chemistry 2006年第5期49卷 385-401页

作者： LI Xuehui1. ZHAO Dongbin2,3. FEI Zhaofu2 & WANG Lefu1.1. Department of Chemical Engineering, Guangdong Provincial Laboratory of Green Chemical Technology, South China Uni-versity of Technology, Guangzhou 51.641. China 2. Swiss Federal Institute of Technology, Lausanne, EPFL, CH-1.1. Lausanne, Switzerland 3. PKU Green Chemistry Center, beijing National Laboratory for Molecular Sciences, College of Chemistry and Molecular Engineering, peking university, beijing {3. China 1. Department of Chemical Engineering Guangdong Provincial Laboratory of Green Chemical Technology South China University of Technology Guangzhou 510641 China 2. Lausanne EPFL Swiss Federal Institute of Technology CH-1015 Lausanne Switzerland 3. PKU Green Chemistry Center Beijing National Laboratory for Molecular Sciences College of Chemistry and Molecular Engineering Peking University Beijing 100871 China

Recent developments of the synthesis and applications of functionalized ionic liquids (including dual-functionalized ionic liquids) have been highlighted in this review. Ionic liquids are at-tracting attention as alternative solvents in green chemistry, but as more functionalized ILs are pre-pared, a greater number of applications in increasingly diverse fields are found.

关键词： ionic liquids functionalized ionic liquids dual-functionallzed ionicliquids reaction media asymmetric synthesis nano-materials porous materials lubricants flue-gas desulfurization oil desul-furization

Implantable CMOS neuro-stimulus chip for visual prosthesis

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Science China(Information Sciences) 2011年第4期54卷 898-908页

作者： ZHANG Xu 1.PEI WeiHua 1.HUANG BeiJu 1.WANG ShuJing 1.GUAN Ning 1.GUO Kai 1.WANG Yu 1.GUI Qiang 1.CHEN Jin 1.WANG Kai 2,WU HuiJuan 2,LI XiaoXin 2,LI Kai 3.& CHEN HongDa 1.1.State Key Laboratory on Integrated Optoelectronics,Institute of Semiconductors,Chinese Academy of Sciences,{1. 1.0083.China 2 Department of Ophthalmology,People’s Hospital of peking university,{1. 1.0044,China 3.Department of Epidemiology and Biostatistics,Health Science Center,peking university,{1. 1.0083.China 1. State Key Laboratory on Integrated Optoelectronics Institute of Semiconductors Chinese Academy of Sciences Beijing 100083 China2. Department of Ophthalmology People’s Hospital of Peking University Beijing 100044 China3. Department of Epidemiology and Biostatistics Health Science Center Peking University Beijing 100083 China

A prototype chip with 2×2 pixels for implanting in blind patients affected by outer retinal degeneration is presented in this *** visual prosthesis chip imitates the degenerated photoreceptor cells,senses the incident light and stimulates the remaining healthy layers of retina or optic *** pixel integrates photodiode and stimulus pulse generator,converting the illumination on the eyes into 3.bit resolution bi-phasic current ***-chip charge cancellation modules are used to discharge each electrode site for tissue *** prototype chip is designed and fabricated in 0.1.-μm N-well CMOS (complementary metal oxide semiconductor) 1.6M Mix-signal process,with a ±2.5 V dual voltage *** functionality of the fabricated chip is demonstrated on anesthetized *** responses in visual cortex are successfully evoked by the neuro-stimulus chip through an on-board trigger interface and flexible electrode.

关键词： biomedical microelectronics visual prosthesis functional electrical stimulation acute animal ex- periment electrical evoked potential (EEP) test

The refined theory of deep rectangular beams based on general solutions of elasticity

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Science China(Physics,Mechanics & Astronomy) 2006年第3期49卷 291-303页

作者： GAO Yang1.& WANG Minzhong2 1. College of Science, China Agricultural university, {1. 1.0083. China 2. State Key Laboratory for Turbulence and Complex Systems and Department of Mechanics and Engi- neering Science, peking university, {1. 1.0871. China College of Science China Agricultural University Beijing 100083 China State Key Laboratory for Turbulence Complex Systems Department of Mechanics Engineering Science Peking University Beijing 100871 China

The problem of deducing one-dimensional theory from two-dimensional the- ory for a homogeneous isotropic beam is investigated. Based on elasticity theory, the re- fined theory of rectangular beams is derived by using Papkovich-Neuber solution and Lur’e method without ad hoc assumptions. It is shown that the displacements and stresses of the beam can be represented by the angle of rotation and the deflection of the neutral surface. Based on the refined beam theory, the exact equations for the beam without transverse surface loadings are derived and consist of two governing differential equations: the fourth-order equation and the transcendental equation. The approximate equations for the beam under transverse loadings are derived directly from the refined beam theory and are almost the same as the governing equations of Timoshenko beam theory. In two ex- amples, it is shown that the new theory provides better results than Levinson’s beam the- ory when compared with those obtained from the linear theory of elasticity.

关键词： deep rectangular beams,the refined theory,Papkovich-Neuber solution,Lur'e method,governing equation

Expression of PDCD5 , a novel apoptosis related protein, in human osteoarthritic cartilage

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Acta Pharmacologica Sinica 2004年第05期25卷 143-148页

作者： Ai-xin CHENG, Si-quan LOU2, Hao-wei ZHOU, Ying WANG3. Da-long MA3.epartment of Orthopaedic Surgery, Third Hospital, peking university, beijing 1.0083.3.enter for Human Disease Genomics, peking university, beijing 1.0083. China Department of Orthopaedic Surgery Third Hospital Peking University Center for Human Disease Genomics Peking University

AIM: To investigate the expression features of PDCD5 (programmed cell death 5 protein) in osteoarthritic andnormal human cartilage, and speculate on its potential functions in the pathogenesis of osteoarthritis (OA).METHODS: Articular cartilage specimens were obtained from 3. patients with OA and 1. healthy patients at thetime of arthroplasty. Expression of PDCD5 was detected by flow cytometry, immunofluorescence, RT-PCR andimmunohistochemical analysis. RESULTS: Enhanced expression and nuclear accumulation of PDCD5 in OAchondrocytes were found. PDCD5-positive chondrocytes were mainly distributed in the superficial and deep zonesof OA tissue sections, as opposed to, in the superficial and middle regions of normal healthy tissue ***: Since apoptotic chondrocyte death occurs more frequently in OA cartilage than in normal healthycartilage and PDCD5 is an apoptosis-related protein, the different expression patterns of PDCD5 in OA cartilagefrom that in normal healthy cartilage indicate that PDCD5 is involved in the pathogenesis of OA.

关键词： apoptosis cartilage osteoarthritis PDCD5

Kinematics and dynamics of the Mesozoic orogeny and late-orogenic extensional collapse in the Sino-Mongolian border areas

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Science China Earth Sciences 2005年第7期48卷 849-862页

作者： ZHENG Yadong 1.& WANG Tao2 1. Key Laboratory of Orogenic Belts and Crustal Evolution (peking university), Ministry of Education, {1. 1.0871. China 2. Institute of Geology, Chinese Academy of Geological Sciences, {1. 1.003., China Key Laboratory of Orogenic Belts and Crustal Evolution (peking university) Ministry of Education Beijing 100871 China Institute of Geology Chinese Academy of Geological Sciences Beijinq 100037 China

The Sino-Mongolian border areas underwent two important tectonic events during Mesozoic time after late Paleozoic orogeny: a late Triassic to earlier Jurassic contractional event that resulted in a large-scale south-vergent thrust during the orogeny and a late Jurassic-earlier Cretaceous extensional event in a north-south direction that formed a metamorphic core complex. The kinematic and dynamic analyses show that the thrust sheet moved southwards with a kinematic vorticity number of ca. -0.1. and sub-horizontal maximum compressive stress axis that belongs to a contraction-thickening shear. The upper plate of the late-orogenic detachment relatively moved in a 1.5°direction. The average kinematic vorticity in its earlier stage was 0.74 that belongs to simple shear dominated shearing and related to the maximum compressive stress axes dipping at ～66°, while the later average kinematic vorticity was ～0.55°that belongs to pure shear dominated shearing with sub-vertical maximum compressive stress axes. This suggests that the thrusting led to the crust thickened and the lower plate rocks that were originally located in the upper crust depressed through a brittle-ductile transition zone into the lower crust and became warmer. The heated rocks trended to uplift since their increasing volume and decreasing density while the loading of the upper-plate rocks increased due to the structural thickening. Under the combined effect of the loading and the thermal-uplifting, the ductile shear zone in between increased in its component of vertical pure shear. Once its pure-shear component exceeded its simple-shear one the ductile shear zone became an extension-thinned shear zone. This progressive transitional process reflects internal and essential temporal and spatial relationships: the extensional factor nucleated during the crust thickening by thrusting and increase of the extensional factor finally led to late-orogenic collapse.

关键词： Mesozoic thrusting,late-orogenic collapse,kinematic vorticity number,stress state.

The refined theory of transversely isotropic piezoelectric rectangular beams

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Science China(Physics,Mechanics & Astronomy) 2006年第4期49卷 473-486页

作者： GAO Yang1.& WANG Minzhong2 1. College of Science, China Agricultural university, {1. 1.0083. China 2. State Key Laboratory for Turbulence and Complex Systems and Department of Mechanics and Engi- neering Science, peking university, {1. 1.0871. China 1. College of Science China Agricultural University Beijing 100083 China 2. State Key Laboratory for Turbulence and Complex Systems and Department of Mechanics and Engineering Science Peking University Beijing 100871 China

The problem of deducing one-dimensional theory from two-dimensional theory for a transversely isotropic piezoelectric rectangular beam is investigated. Based on the piezoelasticity theory, the refined theory of piezoelectric beams is derived by using the general solution of transversely isotropic piezoelasticity and Lur'e method without ad hoc assumptions. Based on the refined theory of piezoelectric beams, the exact equations for the beams without transverse surface loadings are derived, which consist of two governing differential equations: the fourth-order equation and the transcendental equation. The approximate equations for the beams under transverse loadings are derived directly from the refined beam theory. As a special case, the governing differential equations for transversely isotropic elastic beams are obtained from the corresponding equations of piezoelectric beams. To illustrate the application of the beam theory developed, a uniformly loaded and simply supported piezoelectric beam is examined.

关键词： rectangular beams, the refined theory, piezoelectric, transversely isotropic.

Distinct actions of intermittent and sustained β-adrenoceptor stimulation on cardiac remodeling

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Science China(Life Sciences) 2011年第6期54卷 493-501页

作者： MA XiaoWei1.3.SONG Yao1.3.CHEN Chao1.3.FU YongNan1.3.SHEN Qiang2,3.LI ZiJian1.3.& ZHANG YouYi1.3.1.nstitute of Vascular Medicine,peking university Third Hospital,beijing 1.01.1.China 2Institute of Cardiovascular Science,peking university,beijing 1.01.1.China 3.ey Laboratory of Molecular Cardiovascular Sciences,Ministry of Education,beijing 1.01.1.China 1. Institute of Vascular Medicine Peking University Third Hospital Beijing 100191 China3. Key Laboratory of Molecular Cardiovascular Sciences Ministry of Education Beijing 100191 China2. Institute of Cardiovascular Science Peking University Beijing 100191 China

Heart disease is associated with increased sympathetic nerve activity and elevated levels of circulating catecholamines,resulting in chronic stimulation of the β-adrenergic receptors (β-AR) and consequent pathological cardiac ***,chronic administration of the β-AR agonist isoproterenol (ISO) has been most commonly used to model β-AR-induced cardiac ***,it remains unclear whether β-AR-mediated cardiac remodeling and dysfunction differs between sustained versus pulsatile (intermittent) exposure to a β-***,we compare the effects of intermittent versus sustained administration of ISO on cardiac remodeling and function in *** were administered 5 mg (kg d)-1.ISO for 2 weeks either by daily subcutaneous injection,or continuous infusion via an implanted osmotic *** function and remodeling were determined by echocardiography,micromanometry and ***,Western blotting and quantitative real-time polymerase chain reaction (qRT-PCR) were utilized to define the proteins and genes *** sustained and intermittent administration of ISO resulted in a similar degree of cardiac hypertrophy (1.% and 1.%,respectively).However,mice receiving ISO by daily injection developed more severe ventricular systolic and diastolic dysfunction and myocardial fibrosis compared with mice receiving ISO via the osmotic *** disparity in results between the delivery methods is suggested to be due,at least in part,to increased expression of fibrogenic factors,including connective tissue growth factor (CTGF) and NADPH oxidase (NOX4),in mice receiving intermittent application of *** summary,compared with sustained exposure to a β-AR agonist,intermittent β-AR stimulation leads to more severe cardiac dysfunction and *** findings not only further our understanding of β-AR function in the setting of cardiac pathophysiology,but also highlight that significant differences can result dependent upon the mod

关键词： β-adrenoceptor reactive oxygen species NADPH oxidase cardiac hypertrophy cardiac fibrosis