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Influence of valence electron structures of phase and biphase interfaces of sulfides on hot brittleness in steel

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Science china(Technological Sciences) 2004年第4期47卷 488-504页

作者： LIU Yan1.3. LIU Zhilin1. ZHANG Chengwei1.{1.& ZHOU Yingchun1.1. Liaoning Institute of Technology, Jinzhou 1.1.001. china {1. china {{1. Oil and Gas Exploration and Development Corporation, Beijing 1.001., china 3. College of Science, Northeastern University, Shengyang 1.0006, china 1. Liaoning Institute of Technology 121001 Jinzhou China 2. College of Science Northeastern University 110006 Shengyang China 3. {1. national Oil and Gas Exploration and Development Corporation 100011 Beijing China

This paper calculates the electron structures of phase of FeS, MnS and their biphase interface electron structures with austenite in steel. The precipitation and the transformation of FeS and MnS are investigated through studying the valence electron pair numbers on the strongest bond n A with the structure formation factor S. The continuity of electron density and its relation with stress are explored in the biphase interfaces with the electron density difference απ Using n A, S, απ we explain the reason why FeS can bring about hot brittleness in steel and the physical mechanism why MnS may eliminate or inhibit hot brittleness, based on which satisfying results are obtained by calculating several rare-earth sulfides.

关键词： valence electron structure, sulfide, hot brittleness, and rare earth.

Comprehensive evaluation of mechanism of "chimney effect" using principles of magnetism, geochemistry and mineralogy

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Chinese Science Bulletin 1998年第9期43卷 743-748页

作者： LIU Qingsheng 1. CHENG Tongjin 2.and LIU Shugen {1.1. Department of Applied Geophysics, china University of Geosciences, Wuhan 4{1.074, china 2. Center of Petroleum Geochemistry, china national Star Petroleum Corporation, Hefei 2.002., china {1. The St Department of Applied Geophysics China University of Geosciences Wuhan China Center of Petroleum Geochemistry China National Star Petroleum Corporation Hefei China The State Key Laboratory of Oil/Gas Reservoir Geology and Exploitation of china Chengdu Institute of Technology Chengdu China

Study of forming mechanism of "chimney-effect" (CE) has important significance for basic theory and applications of non-seismic geophysical and geochemical methods locating oil/gas reservoirs. The theoretical basis of comprehensive evaluation of mechanism of CE using principles of magnetism, geochemistry and mineralogy has been reviewed, with the problems to be solved: (ⅰ) study for the relationship between process of oil/gas migration and geochemical field; (ⅱ) analysis of genesis of magnetic, geochemical and mineralogical anomaly; (ⅲ) interpretation of surface soil magnetism and geochemical anomaly combined with seismic data.

关键词： chimney effect (CE) hydrocarbon microseepage oil/gas accumulation.

Real-World Treatment Adherence to Smoking Cessation Medications and Association with Treatment Outcome—2. Centers,{1.,2.1.–2.2.

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china CDC weekly 2024年第22期6卷 522-529,I0001-I0003页

作者： Anqi Cheng Zhao Liu Xinmei Zhou Zheng Su Dan Xiao Chen Wang the china {1. Tobacco Cessation Cohort Study(CNTCCS)Study Group Department of Tobacco Control and Prevention of Respiratory Disease Center of Respiratory MedicineChina-Japan Friendship Hospital/WHO Collaborating Center for Tobacco Cessation and Respiratory Diseases Prevention/National Center for Respiratory Medicine/National Clinical Research Center for Respiratory Diseases/Institute of Respiratory MedicineChinese Academy of Medical SciencesBeijingChina Department of Pulmonary and Critical Care Medicine Center of Respiratory MedicineChina-Japan Friendship Hospital/WHO Collaborating Center for Tobacco Cessation and Respiratory Diseases Prevention/China National Center for Respiratory Medicine/China National Clinical Research Center for Respiratory DiseasesBeijingChina Chinese Academy of Medical Sciences and Peking Union Medical College BeijingChina 不详

What is already known about this topic?Medication non-adherence significantly impedes smoking cessation *** effective smoking cessation medications are accessible in china,realworld adherence and its correlation with treatment outcomes remain largely *** is added by this report?From December {1.1. to January {1.{1.,1.1.1. participants were recruited from {1. centers in all seven geographical regions of *** revealed that only 3..{1.of smokers adhered to the prescribed 1.1.week smoking cessation treatment and those with a higher education level were more likely to be *** addition,smokers with good adherence were more likely to successfully quit *** are the implications for public health practice?The data obtained could enhance our understanding of smoking cessation practices in *** adherence is a crucial strategy to enhance the effectiveness of smoking cessation treatments and management provided to smokers.

关键词： china smoke likely

The regular representation and regular covariant representation of crossed products of Woronowicz C^(*)-algebras

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Science china Mathematics 2005年第9期48卷 1245-1259页

作者： ZHANG Xiaoxia~(1.2. & GUO Maozheng~(1.{1. 1. School of Mathematical Sciences,Peking University,Beijing 1.0871.china 2. Department of Mathematics,Yantai University,Yantai 2.4005,china {1. LMAM,Peking University,Beijing 1.0871.china 1. School of Mathematical Sciences Peking University 100871 Beijing China 2. Department of Mathematics Yantai University 264005 Yantai China 3. LMAM Peking University 100871 Beijing China

In this paper,it is shown that the regular representation and regular covariant representation of the crossed products A×α G correspond to the twisted multiplicative unitary operators,where A is a Woronowicz C~*-algebra acted upon by a discrete group ***,it is also shown that the regular covariant C~*-algebra is the Woronowicz C~*-algebra which corresponds to a multiplicative ***,an explicit description of the multiplicative unitary operator for C(SU_q(2. )×α (?) is given in terms of those of the Woronowicz C~*-algebra C(SU_q(2. ) and the discrete group G.

关键词： multiplicative unitary operator, Woronowicz C*-algebra, crossed product.

A preliminary study on seismic design criteria of offshore platforms in Bohai Sea of china

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Earthquake Engineering and Engineering Vibration 2010年第2期9卷 223-231页

作者： Peng Yanju1,Lu Yuejun1,Yan Jiaquan2.Tang Rongyu1,Wang Junqin3.and Li Jiagang3.1. Institute of Crustal Dynamics,china Earthquake Administration,Beijing 100085,china 2. Institute of Geophysics,china Earthquake Administration,Beijing 100081,china 3. Beijing Research Center of china national Offshore Oil Corp.,Beijing 10002.,china Institute of Crustal Dynamics China Earthquake Administration Beijing 100085 China

This paper analyzes the seismicity in Bohai Sea,introducing a shape factor K to characterize the seismic risk distribution in sub-regions of the sea. Based on the seismic design ground motions for 46 platforms located in the Bohai Sea,a statistical analysis was performed for different peak ground acceleration (PGA) ratios at two different probability levels. In accordance with the two-stage design method,a scheme of two seismic design levels is proposed,and two seismic design objectives are established respectively for the strength level earthquake and the ductility level earthquake. By analogy with and comparison to the Chinese seismic design code for buildings,it is proposed that the probability level for the strength level earthquake and ductility level earthquake have a return period of 2.0 and 1.00 - 2.00 years,respectively. The validity of these proposed values is discussed. Finally,the PGAs corresponding to these two probability levels are calculated for different sub-regions of the Bohai Sea.

关键词： fixed offshore platform seismic design level seismic design objective return period Bohai Sea

Direct CP violation in hadronic B decays

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Science china(Physics,Mechanics & Astronomy) 2006年第3期49卷 357-366页

作者： HONG Bihai1,2.& Lü Caidian3.1. Department of Physics, Lishui University, Lishui 3.0}000,china 2. Department of Physics, Shanghai Jiaotong University, Shanghai 2.003., china 3. Institute of High Energy Physics, Beijing 100049,china Department of Physics Lishui University Lishui 323000 China Department of Physics Shanghai Jiaotong University Shanghai 200030 China Institute of High Energy Physics Beijing 100049 China

There are different approaches for the hadronic B decay calculations, recently. In this paper, we upgrade three of them, namely factorization, QCD factorization and the perturbative QCD approach based on kT factorization, using new parameters and full wave functions. Although they get similar results for many of the branching ratios, the direct CP asymmetries predicted by them are different, which can be tested by recent experimental measurements of B factories.

关键词： CP violation hadronic B decay factorization.

Water target based cross-calibration of CBERS-02.CCD camera with MODIS data

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Science china(Technological Sciences) 2005年第S2期48卷 61-71页

作者： TANG Junwu1.2. GU Xingfa2. NIU Shengli1. MA Chaofei1.& MIN Xiangjun3.1. national Satellite Ocean Application Service (NSOAS), Beijing 1.0081. {3. 2. State Key Laboratory of Remote Sensing Science, Beijing 1.001., {3. 3. {3. Center for Resource Satellite Data and Applications (CRESDA), Beijing 1.0083. {3. 1. national Satellite Ocean Application Service (NSOAS) 100081 Beijing China 2. State Key Laboratory of Remote Sensing Science 100010 Beijing China 3. {1. Center for Resource Satellite Data and Applications (CRESDA) 100083 Beijing China

In order to make quantitative watercolor sensing with china-Brazil Earth Resources Satellite (CBERS-0{1. CCD camera, the MODIS data with higher accuracy is used to cross-calibrate the CCD camera over water targets. In homogeneous clear water area, two pairs of images obtained over the same area on the same day by the two sensors are selected. The top-of-atmosphere (TOA) radiances of the multispectral bands of CCD are calculated with the water and aerosol parameters from MODIS based on a water-atmosphere radiative transfer algorithm. The stripes in CCD image that caused by unequal response of the CCD array detectors are firstly removed before making the cross-calibration. The same part of CCD detectors is selected for the calibrations in the two images to eliminate the residual error of destriping and uniformity correction for the focus plane irradiance. It is shown that the calibration results from two different images are consistent. The error of this method is about 5%.

关键词： CBERS-02 CCD MODIS radiometric calibration cross-calibration. DOI: 1..1.0}0/05ze1.06

The coupling instability of Rossby and topographic Rossby waves in the equatorial area

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Science china Earth Sciences 2005年第10期48卷 1792-1801页

作者： CHAO Jiping1.2. LIU Lin1.{1.& YU Weidong1.1. Laboratory of Marine Science and Numerical Modeling, State Oceanic Administration, Qingdao 2.6061. china 2. national Research Center for Marine Environmental Forecasts, State Oceanic Administration, Beijing 1.0081. china {1. Ocean University of china, Qingdao 2.600{1. china Laboratory of Marine Science and Numerical Modeling State Oceanic Administration Qingdao china national Research Center for Marine Environmental Forecasts State Oceanic Administration Beijing {1. Ocean University of china Qingdao china

In case of considering the fact that the tropical ocean thermocline or the lower at-mosphere height field has the meridional variation, the topographic Rossby wave will be excited. Also the background geostrophic current emerges. Under such conditions, the topographic Rossby wave can interact with the classical Rossby wave at some parameter band and thus brings a new kind of instability, which may be of potential application in understanding some phenomena of the ENSO cycle.

关键词： thermocline variation, equatorial jet, Rossby wave, topographic Rossby wave, coupling instability

Effect of rock mass structure and block size on the slope stability——Physical modeling and discrete element simulation

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Science china(Technological Sciences) 2005年第z1期48卷 1-17页

作者： LI Shihai1. LIAN Zhenzhong1.2.& J. G. Wang{1.1. Institute of Mechanics, Chinese Academy of Sciences, Beijing 1.0080, china 2. Graduate School, Chinese Academy of Sciences, Beijing 1.0060, china {1. Tropical Marine Science Institute, {2. University of Singapore, Singapore 1.92.0 Chinese Acad Sci Inst Mech Beijing 100080 Peoples R China Chinese Acad Sci Grad Sch Beijing 100060 Peoples R China Natl Univ Singapore Trop Marine Sci Inst Singapore 119260 Singapore

This paper studies the stability of jointed rock slopes by using our improved three-dimensional discrete element methods (DEM) and physical modeling. Results show that the DEM can simulate all failure modes of rock slopes with different joint configurations. The stress in each rock block is not homogeneous and blocks rotate in failure development. Failure modes depend on the configuration of joints. Toppling failure is observed for the slope with straight joints and sliding failure is observed for the slope with staged joints. The DEM results are also compared with those of limit equilibrium method (LEM). Without considering the joints in rock masses, the LEM predicts much higher factor of safety than physical modeling and DEM. The failure mode and factor of safety predicted by the DEM are in good agreement with laboratory tests for any jointed rock slope.

关键词： rock masses, slope stability, DEM simulation, block size effect, joints configuration effect, limit equilibrium method.