检索结果-南通市图书馆

Refinement of packet size in low carbon bainitic steel by special thermo-mechanical control process

在线全文

学校读者我要写书评

暂无评论

Journal of university of Science and Technology beijing 2004年第3期11卷 221-224页

作者： Chengjia Shang Xuemin Wang Shanwu Yang Xinlai He Materials Science and Engineering school, university of Science and Technology beijing, beijing 100083,{4. Mat. Sci. and Eng. Sch. Univ. of Sci. and Technol. Beijing Beijing 100083 China

The packet size of bainitic steel can be refined by a specialrelaxation-precipitation-control phase transformation (RFC) technology. When processed by RPCprocess, the low carbon bainitic steel composes of two kinds of main intermediate transformationphases. One is ultra-fine lath-like bainitic ferrite and the lath is less than 1μm in width andabout 6 μm in length; the alignment of laths forms a refined packet, and the size of packets isabout 5-7 μm in length and about 3-4.m in width. The other is acicular structure. The morphologyand distribution of these acicular structures are influenced by relaxation process, the thin andshort acicular structures cut the prior austenite grain and refine the bainitic packet size. For theoptimum relaxation time, the packet size can be refined to the finest. The mechanical propertiesare influenced by relaxation time and the 800 MPa grade low carbon bainitic steel with excellenttoughness can be obtained by RPC process.

关键词： packet size refinement bainitic steel RPC process

Sticking-up Behaviors and Surface Friction of IF Electrogalvanized Sheet Steel in Forming

在线全文

学校读者我要写书评

暂无评论

International Journal of Minerals,Metallurgy and Materials 1999年第1期13卷 61-63,68页

作者： Jiming Hu Jixun Wu Yanping Lu Yanrong Zhu (Material Science and Engineering school, university of Science and Technology beijing, beijing 100083,{4.) Univ of Science and Technology Beijing Beijing China

X-ray diffraction (XRD), ball-disc friction and wearing machine and draw-bead test were introduced to investigat the strcusture and workability of IF sheet steel electrogalvanized deposits prepared from sulphate solution system. It was shown that the picking-up of the zinc coating on die strengthened with the increasing of friction factor which was originally affected by the coating's structure. Duing forming, (00X) planes (X= 2, 4. preferential orientation of zinc deposits increased, which resulted in enhanc ing the coating's friction behaviors. Therefore, the forming mechanism of electrogalvedzed deposit was demonstrated that both friction and the stricking -up behaviors of the coating are intensified simultaneously and affect each other.

关键词： electrogalvanized deposit forming friction factor

Archean relic body at lower crust in Sulu area:Evidence from magnetic data

在线全文

学校读者我要写书评

暂无评论

Chinese Science Bulletin 2003年第6期48卷 589-593页

作者： WU Qifan1,2, LU Fengxiang3, LIU Qingsheng3, ZHENG Jianping3, WANG Maoji2 & WU Wenli4.1. Department of Engineering Physics, Tsinghua university, beijing 100084. china 2. Aero Geophysical Survey & Remote Sensing Center, beijing 100083, china 3. china university of geosciences, Wuhan 4.0074. china 4. Institute of Geophysical & Geochemical exploration, Langfang 065000, china Aero Geophysical Survey & Remote Sensing Center Beijing 100083 China china university of geosciences Wuhan 430074 China Institute of Geophysical & Geochemical exploration Langfang 065000 China Department of Engineering Physics Tsinghua University Beijing 100084 China

After the new 1︰1000000 aero magnetic data were processed and the three-dimensional inversion work was carried out, a vast high magnetic body northwestward was discovered. The magnetic body is located at the depth of about 20 km on the west side of Tanlu fault and at about 25 km on the east side of Tanlu fault beneath the Sulu area. There is a difference of vertical distance of 3—5 km in depth between both sides. We think that the magnetic body is an Archean metamorphic plate and belongs to the North china block. The discovery of the magnetic body is significant for us to reconstruct the structure model of the Sulu orogenic belt, delineate the suture of collision between the North china block and the Yangtze block, and estimate the depth of slipping surface when the eastside of Tanlu fault moved northward.

关键词：苏鲁地区地壳下层太古代残余体地球物理调查区域性磁场三维反演苏鲁造山带郯鲁断裂带大别-苏鲁超高压变质带

Multiparty simultaneous quantum identity authentication with secret sharing

在线全文

学校读者我要写书评

暂无评论

Science china(Physics,Mechanics & Astronomy) 2008年第3期51卷 321-327页

作者： YANG YuGuang1,2,WEN QiaoYan3 & ZHANG Xing4.5 1 College of Computer Science and Technology,beijing university of Technology,beijing 100022,china 2 State Key Laboratory of {4. Security (Graduate university of the Chinese Academy of Sciences),beijing 10004.,china 3 school of Science,beijing university of Posts and Telecommunications,beijing 100876,china 4.Institute of Electronic Technology,{4. Engineering university,Zhengzhou 4.0004.china 5 Trusted Computing Laboratory,beijing university of Technology,beijing 100022,china College of Computer Science Technology Beijing University of Technology Beijing 100022 China State Key Laboratory of information Security [Graduate university of the Chinese Academy of Sciences] Beijing 100049 China school of Science Beijing University of Posts Telecommunications Beijing 100876 China Institute of Electronic Technology Information Engineering University Zhengzhou 450004 China Trusted Computing Laboratory Beijing University of Technology Beijing 100022 China

Two multiparty simultaneous quantum identity authentication (MSQIA) protocols based on secret sharing are presented. All the users can be authenticated by a trusted third party (TTP) simultaneously. In the first protocol,the TTP shares a random key K with all the users using quantum secret sharing. The ith share acts as the authentication key of the ith user. When it is necessary to perform MSQIA,the TTP generates a random number R secretly and sends a sequence of single photons encoded with K and R to all the users. According to his share,each user performs the corresponding unitary operations on the single photon sequence sequentially. At last,the TTP can judge whether the impersonator exists. The sec-ond protocol is a modified version with a circular structure. The two protocols can be efficiently used for MSQIA in a network. They are feasible with current technol-ogy.

关键词： quantum identity authentication secret sharing quantum cryptography

"Three-Component" Digital Prospecting Method: A New Approach for Mineral Resources Quantitative Prediction and Assessment

在线全文

学校读者我要写书评

暂无评论

Journal of Earth Science 2004年第3期 6-13页

作者： Zhao Pengda Chioa university of geosciences, Wuhan 4.0074. china Chen Jianping school of the Earth Sciences and Resources,{4., beijing 100083, china Chen Jianguo Institute of Mathematical Geology,{4., Wuhan 4.0074. china Zhang Shouting school of the Earth Sciences and Resources,{4., beijing 100083, china Chen Yongqing china Geological Survey, {14. 100073, china

Three-component" method consists of three close-connected aspects: geological anomaly, diversity of mineralization and mineral deposit spectrum. All these three concepts are not new separately, but it is a new approach to combine these three aspects in one single concept for quantitative mineral resources prediction and assessment and it is also the first time to conduct a more detailed study in each aspect. Investigation and clarification of geological anomalies, diversity of mineralization and spectrum of mineral deposits are realized by digitization and quantification of ore forming controlling factors, ore-existing symbols or marks, characteristics of mineralization and regulation of ore-genesis and laws of distribution. These procedures lead to construction of a "digital model" for mineral resources prediction and assessment.

关键词： three-component" method geological anomaly diversity of mineralization spectrum of mineral deposits.

A kind of coccoid dinoflagel-lates-like fossils gives a new explanation of source of dinosterane in the Early-Middle Cambrian

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

Chinese Science Bulletin 2001年第5期46卷 420-423,442页

作者： BIAN Lizeng, ZHANG Shuichang, ZHANG Baomin, MAO Shaozhi & YIN LeimingDepartment of Earth Sciences, Nanjing university, Nanjing 210093,china Key Laboratory of Petroleum Geochemistry, china National Petroleum Corporation, beijing 100083, china Research Institute of Petroleum exploration and Development, china National Petroleum Corporation, beijing 100083, china china university of geosciences, beijing 100083, china Nanjing Institute of Geology and Palaeontology, Chinese Academy of Sciences, Nanjing 210008, china Department of Earth Sciences Nanjing University Nanjing China Key Laboratory of Petroleum Geochemistry China National Petroleum Corporation Beijing China Research Institute of Petroleum exploration and Development China National Petroleum Corporation Beijing China china university of geosciences Beijing China Nanjing Institute of Geology and Palaeontology Chinese Academy of Sciences Nanjing China

The coccoid fossils covered with thick gelatinous envelop containing several gametes are discovered in gyps and salt deposits of Cambrian, H4.well and chert bed of the base of Yuertus Formation (∈11) of Xiaoerbulake Section. The fossils are described and compared with coccoid dinoflagellates. These fossils may be a coccoid life-cycle stage (vegetative cyst) of coccoid dinoflagellates. If this identification is correct, the coccoid dinoflagellates-like fossils could give a reasonable explanation of the dinoflagellate-specific biomarkers from Cambrian, H4.well, Tarim Basin.

关键词： coccoid dinoflagellates-like fossils dinoflagellate-specific biomarkers Cambrian Tarim Basin.

Patterns of platinum-group elements in mantle peridotite, granulite xenoliths and basalt in Hannuoba

在线全文

学校读者我要写书评

暂无评论

Chinese Science Bulletin 1999年第18期44卷 1676-1681页

作者： CHU Xuelei, LI Xiaolin, XU Jiuhua and LIU Jianming1. The Research Center of Mineral Resources exploration , Chinese Academy of Sciences , beijing 100101, china 2. Institute of Geology , Chinese Academy of Sciences , beijing 100029, china 3. Institute of High Energy Physics , Chinese Academy of Sciences , beijing 100817 , china 4. beijing university of Science and Engineering , beijing 100083, china Corresponding author The Research Center of Mineral Resources exploration Chinese Academy of Sciences Beijing China Institute of Geology Chinese Academy of Sciences Beijing China Institute of High Energy Physics Chinese Academy of Sciences Beijing China beijing university of Science and Engineering Beijing China

Neutron activation analysis after preconcentration of nickel sulfide fire assay was used in measurement of Ru, Ph, Pd, Os, Ir, Pt (i.e. PGE elements) and Au concentrations for basalt, mantle and granulite xenoliths in Hannuoba. The chondrite- and primitive mantle-normalized PGE patterns generally exhibit flat (for Iherzolite), negative slope (for harzburgite),

关键词： mantle xenolith granulite xenolith basalt platinum-group element Hannuoba.

An analysis of seismic attenuation in random porous media

在线全文

学校读者我要写书评

暂无评论

Science china(Physics,Mechanics & Astronomy) 2010年第4期53卷 628-637页

作者： LIU Jiong1, BA Jing2, MA JianWei1 & YANG HuiZhu1 1 Institute of Seismic exploration, school of Aerospace, Tsinghua university, beijing 100084.{4. 2 Research Institute of Petroleum exploration & Development, Petrochina, beijing 100083,{4. 1. Institute of Seismic exploration School of Aerospace Tsinghua University Beijing 100084 China2. Research Institute of Petroleum Exploration & Development PetroChina Beijing 100083 China

The attenuation of seismic wave in rocks has been one of the interesting research topics, but till now no poroelasticity models can thoroughly explain the strong attenuation of wave in rocks. In this paper, a random porous medium model is designed to study the law of wave propagation in complex rocks based on the theory of Biot poroelasticity and the general theory of stochastic process. This model sets the density of grain, porosity, permeability and modulus of frame as random parameters in space, and only one fluid infiltrates in rocks for the sake of better simulation effect in line with real rocks in earth strata. Numerical simulations are implemented. Two different inverse quality factors of fast P-wave are obtained by different methods to assess attenuation through records of virtual detectors in wave field (One is amplitude decay method in time domain and the other is spectral ratio method in frequency domain). Comparing the attenuation results of random porous medium with those of homogeneous porous medium, we conclude that the attenuation of seismic wave of homogeneous porous medium is far weaker than that of random porous medium. In random porous media, the higher heterogeneous level is, the stronger the attenuation becomes, and when heterogeneity σ = 0.15 in simulation, the attenuation result is consistent with that by actual observation. Since the central frequency (50 Hz) of source in numerical simulation is in earthquake band, the numerical results prove that heterogeneous porous structure is one of the important factors causing strong attenuation in real stratum at intermediate and low frequency.

关键词： the theory of stochastic process the theory of Biot poroelasticity the attenuation of seismic wave inverse quality factor

Study on attribute characterization for reservoir dynamic monitoring by seismic

在线全文

学校读者我要写书评

暂无评论

Science china Earth Sciences 2008年第S2期51卷 218-225页

作者： CHEN XiaoHong1,3,LI JingYe2,3 & ZHAO Wei4.1 Key Lab of Geophysical exploration of CNPC,china Petroleum university,beijing 10224.,china 2 Basin & Reservoir Research Center,china Petroleum university,beijing 10224.,china 3 State Key Laboratory of Petroleum Resource and Prospecting,china university of Petroleum,beijing 10224.,china 4.Research Center of CNOOC,beijing 100027,china 1. Key Lab of Geophysical exploration of CNPC China Petroleum University Beijing 102249 China 3. State Key Laboratory of Petroleum Resource and Prospecting China University of Petroleum Beijing 102249 China 2. Basin & Reservoir Research Center China Petroleum University Beijing 102249 China 4. Research Center of CNOOC Beijing 100027 China

Study on characterizing reservoir parameters dynamic variations by time-lapse seismic attributes is the theoretical basis for effectively distinguishing reservoir parameters variations and conducting time-lapse seismic interpretation,and it is also a key step for time-lapse seismic application in real oil fields. Based on the rock physical model of unconsolidated sandstone,the different effects of oil saturation and effective pressure variations on seismic P-wave and S-wave velocities are calculated and analyzed. Using numerical simulation on decoupled wave equations,the responses of seismic amplitude with different offsets to reservoir oil saturation variations are analyzed,pre-stack time-lapse seismic attributes differences for oil saturation and effective pressure variations of P-P wave and P-S converted wave are calculated,and time-lapse seismic AVO (Amplitude Versus Offset) response rules of P-P wave and P-S converted wave to effective pressure and oil saturation variations are compared. The theoretical modeling study shows that it is feasible to distinguish different reservoir parameters dynamic variations by pre-stack time-lapse seismic information,including pre-stack time-lapse seismic attributes and AVO information,which has great potential in improving time-lapse seismic interpreta-tion precision. It also shows that the time-lapse seismic response mechanism study on objective oil fields is especially important in establishing effective time-lapse seismic data process and interpreta-tion scheme.

关键词： time-lapse seismic dynamic monitoring rock physical model pre-stack attribute Amplitude Versus Offset (AVO)