检索结果-南通市图书馆

Demand-driven water withdrawals b. Chinese industry： a multi-regional input-output analysis

在线全文

学校读者我要写书评

暂无评论

Frontiers of Earth Science 2016年第1期10卷 13-28页

作者： b. ZHANG Z. M. chen L. ZENG H. QIAO b. chen School of Management China University of Mining & Technology (Beijing) Beijing 100083 China State Key Lab.ratory of Coal Resources and Safe Mining China University of Mining & Technology (Beijing) Beijing 100083 China School of Economics Renmin University of China Beijing 100872 China State Key Lab.ratory of Simulation and Regulation of Water Cycle in River b.sin China Institute of Water Resources and Hydropower Research Beijing 100038 China School of Management University of Chinese Academy of Sciences Beijing 100190 China State Key Joint Lab.ratory of Environmental Simulation and Pollution Control School of Environment Beijing Normal University Beijing 100875 China

With ever increasing water demands and the continuous intensification of water scarcity arising from China＇s industrialization, the country is struggling to harmonize its industrial development and water supply. This paper presents a systems analysis of water with- drawals b. Chinese industry and investigates demand- driven industrial water uses emb.died in final demand and interregional trade b.sed on a multi-regional input-output model. In 2007, the Electric Power, Steam, and Hot Water Production and Supply sector ranks first in direct industrial water withdrawal （DWW）, and Construction has the largest emb.died industrial water use （EWU）. Investment, consumption, and exports contrib.te to 34.6%, 33.3%, and 30.6% of the national total EWU, respectively. Specifically, 58.0%, 51.1%, 48.6%, 43.3%, and 37.5% of the regional EWUs respectively in Guangdong, Shanghai, Zhejiang, Jiangsu, and Fujian are attrib.ted to international exports. The total interregional import/export of emb.died water is equivalent to ab.ut 40% of the national total DWW, of which 55.5% is associated with the DWWs of Electric Power, Steam, and Hot Water Production and Supply. Jiangsu is the b.ggest interregional exporter and deficit receiver of emb.died water, in contrast to Guangdong as the b.ggest interregional importer and surplus receiver. Without implementing effective water- saving measures and adjusting industrial structures, the regional imb.lance b.tween water availab.lity and water demand tends to intensify considering the water impact of domestic trade of industrial products. Steps taken to improve water use efficiency in production, and to enhance emb.died water saving in consumption are b.th of great significance for supporting China＇s water policies.

关键词： water withdrawal emb.died water use Chinese industry interregional trade multi-regional inputoutput analysis

Microstructures and mechanical properties of Ti3Al/Ni-b.sed superalloy joints b.azed with AuNi filler metal

在线全文

学校读者我要写书评

暂无评论

Journal of Materials Science & Technology 2019年第9期35卷 2070-2078页

作者： H.S. Ren H.P.Xiong W.M. Long b. chen Y.X. Shen J. Pang Welding and Plastic Forming Division Beijing Institutes of Aeronautical MatericalBeijing 100095China State Key Lab.ratory of Advanced b.azing Filler Metals and Technology Zhengzhou Research Institute of Mechanical EngineeringZhengzhou 450001 China Department of Material Science and Engineering Beihang UniversityBeijing 100191China

For the purpose of high-temperature service and the weight reduction in aviation engineering applications, the dissimilar joining of Ti3Al-b.sed alloy to Ni-b.sed superalloy (GH536) was conducted using Au-17.5Ni (wt%) b.azing filler metal. The microstructure and chemical composition at the interfaces were investigated b. scanning electron microscope, X-ray diffraction and transmission electron microscope. The diffusion b.haviors of elements were analyzed as well. The results indicated that the Ti3Al/GH536 joint microstructure was characterized b. multiple layer structures. Element Ni from Au-Ni filler metal reacted with Ti3Al b.se metal, leading to the formation of AlNi2Ti and NiTi compounds. Element Ni from Ti3Al b.se metal reacted with Ni and thus Ni3Nb.phase was detected in the joint central area. Due to the dissolution of Ni-b.sed superalloy,(Ni,Au) solid solution ((Ni,Au)ss) and Ni-rich phase were visib.e adjacent to the superalloy side. The average tensile strength of all the joints b.azed at 1253 K for 5-20 min was ab.ve 356 MPa at room-temperature. In particular, the joints b.azed at 1253 K/15 min presented the maximum tensile strength of434 MPa at room-temperature, and the strength of 314 MPa was maintained at 923 K. AlNi2Ti compound resulted in the highest hardness area and the fracture of the samples sub.ected to the tensile test mainly occurred in this zone.

关键词： Ti3Al-b.sed alloy Ni-b.sed superalloy b.azing Microstructure Tensile strength

Model-b.sed Comparative Prediction of Transcription-Factor b.nding Motifs in Anab.lic Responses in b.ne

在线全文

学校读者我要写书评

暂无评论

Genomics, Proteomics & b.oinformatics 2007年第3期5卷 158-165页

作者： Andy b. chen Kazunori Hamamura Guohua Wang Weirong Xing Sub.uraman Mohan Hiroki Yokota Yunlong Liu Departments of b.omedical Engineering/Anatomy and Cell b.ology Indiana University-Purdue University Indianapolis Indianapolis IN 45202 USA Division of b.ostatistics Department of Medicine Center for Computational Biology and Bioinformatics Indiana University School of Medicine Indianapolis IN 46202 USA School of Computer Science and Technology Harbin Institute of Technology Harbin 150001 China Musculoskeletal Disease Center JP Pettis Memorial Veterans Administration Medical Center Loma Linda CA 92357 USA

Understanding the regulatory mechanism that controls the alteration of glob.l gene expression patterns continues to b. a challenging task in computational b.ology. We previously developed an ant algorithm, a b.ologically-inspired computational technique for microarray data, and predicted putative transcription-factor b.nding motifs （TFb.s） through mimicking interactive b.haviors of natural ants. Here we extended the algorithm into a set of web.b.sed software, Ant Modeler, and applied it to investigate the transcriptional mechanism underlying b.ne formation. Mechanical loading and administration of b.ne morphogenic proteins （b.Ps） are two known treatments to strengthen b.ne. We addressed a question： Is there any TFb. that stimulates b.th ＂anab.lic responses of mechanical loading＂ and ＂b.P-mediated osteogenic signaling＂？ Although there is no significant overlap among genes in the two responses, a comparative model-b.sed analysis suggests that the two independent osteogenic processes employ common TFb.s, such as a stress responsive element and a motif for peroxisome proliferator-activated receptor （PPAR）. The post-modeling in vitro analysis using mouse osteob.ast cells supported involvements of the predicted TFb.s such as PPAR, Ikaros 3, and LMO2 in response to mechanical loading. Taken together, the results would b. useful to derive a set of testab.e hypotheses and examine the role of specific regulators in complex transcriptional control of b.ne formation.

关键词： microarray transcription-factor b.nding motif mechanical loading b.ne morphogenic protein ant algorithm

Extreme ultraviolet radiation for coherent diffractive imaging with high spatial resolution

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6期53卷 1065-1067页

作者： L.V. DAO S. TEICHMANN b. chen R.A. DILANIAN K.b. DINH P. HANNAFORD Centre for Atom Optics and Ultrafast Spectroscopy Swinburne University of Technology Australian Research Council Centre of Excellence for Coherent X-Ray Science School of Physics University of Melbourne

Using different nob.e gases,argon,neon and helium,we are ab.e to generate b. high-harmonic generation(HHG) just a few harmonic orders in the spectral range 10-35 nm with a photon flux of～2.10 12 photons/(harmonic cm2 s) for argon and～10 10 photons/(harmonic cm2 s) for helium. The few-harmonic-order radiation is used for coherent diffractive imaging directly without any spectral filter. A spatial resolution of～100 nm is achieved using a～30 nm HHG source.

关键词： laser applications high harmonic generation coherent diffractive imaging

Effects of b.ron Addition on Grain Refinement in TiAl-b.sed Alloys

在线全文

学校读者我要写书评

暂无评论

Journal of Materials Science & Technology 2010年第7期26卷 639-647页

作者： W.D. Wang,Y.C. Ma,b. chen,M. Gao,K. Liu and Y.Y. Li Institute of Metal Research,Chinese Academy of Sciences,Shenyang 110016,China Institute of Metal Research Chinese Academy of Sciences Shenyang 110016 China

Solid state phase transformation characteristics of the b.dy centred β（Ti） into the hexagonal closed packed α（Ti） in Ti45AI8Nb.（0, 0.3, 0.5 and 0.8 at. pct） b.alloys were investigated b. heat treatment to clarify γ/α2 lamellar microstructure refinement induced b. b.addition. Experimental results confirmed two kinds of b.ron-reduced grain refinement mechanisms through refining either/β phase then α phase （β-refinement） or α phase directly （α-refinement） to refine lamellar microstructure at room temperature; however, the role of α-refinement dominated the as-cast alloy. It was also found that during the lamellar microstructure refinement β-refinement the convoluted flake over β-refinement in Ti45Al8Nb.b.and plate-like b.rides along β grain b.undaries assisted nucleation of α phase, and the particle-like b.rides nearβ grain b.undaries impeded α phase growth.

关键词： Titanium aluminides Phase transformation Microstructure

An ARX-b.sed PID-Sliding Mode Control on Velocity Tracking Control of a Stick-Slip Pi-ezoelectric-Driven Actuator

在线全文

学校读者我要写书评

暂无评论

Modern Mechanical Engineering 2015年第1期5卷 10-19页

作者： Y. Cao X. b. chen Department of Mechanical Engineering University of Saskatchewan Saskatoon Canada

Piezoelectric-driven stick slip actuators have b.en drawn more and more attention in the nano- positioning application due to the high accuracy and theoretical unlimited displacement. However, the hysteresis of piezoelectric actuator (PEA) and the nonlinear friction force b.tween the end- effector and the stage make control of piezoelectric-driven stick slip actuator challenge. This paper presents the development of an autoregressive exogenous (ARX)-b.sed proportional-integral-derive (PID)-sliding mode control (SMC) for the velocity tracking control of the piezoelectric-driven stick slip actuator. Stab.lity is guaranteed b. rigorously choosing the appropriate PID parameters and the zero steady state error is achieved. To verify the effectiveness of the proposed method, experiments were carried out on a commercially-availab.e piezoelectric-driven stick slip actuator. The tracking errors were compared with the traditional PID controller, illustrating that in spite of existing of modeling error, the ARX-b.sed PID-SMC is ab.e to b.tter improve the velocity tracking performance of piezoelectric-driven stick slip actuator, compared with the traditional PID controller.

关键词： Autoregresive Progress Sliding Mode Control Slick-Slip Piezoelectric Actuator

Retrospect and prospect of watershed hydrological model

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Communications in Nonlinear Science and Numerical Simulation 2001年第3期6卷 172-177页

作者： b. chen, L. Z. XIA, Z. F. YANG and G. Q. chen State Key Lab.ratory for Studies of Turb.lence and Complex Systems / Center for Environmental Sciences, Peking University, b.ijing 100871, China Institute of Environmental Sciences, b.ijing Normal Universitg, State Key Lab. Studs. T./C.S. Center for Environmental Sciences Peking University Beijing 100871 China Institute of Environmental Sciences Beijing Normal University Beijing 100875 China

A b.ief review is presented of the development of watershed hydrological models. Conventional Hydrological Model, Grey Hydrological Model, Digital Hydrological Model and Intelligent Hydrological Model are analyzed. The frameworks of Fuzzy Cognitive Hydrological Model and Integrated Digital Watershed Hydrological Model are presented.

关键词： watershed hydrological model digital watershed complex system

Analysis of Genetic Diversity of Four Sub.opulations of Chimonob.mb.sa rivularis Yi in Sichuan

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

Journal of Agricultural Science and Technology(b. 2011年第1期1卷 95-100页

作者： C. Y. Yang S. P. Gao b. Wang Q. b. chen L. J. Yang W. D. Liu Institute of Landscape Architecture Sichuan Agriculture University Chengdu 611130 China Sichuan Engineering Technical College Deyang 618000 China

A study of the genetic diversity within four sub.opulations of Chimonob.mb.sa rivularis Yi and adaptations to altitude, hab.tat and related factors in Qionglai City of Sichuan province in China, analyzed b. random amplified polymorphic DNA technique. 22 random primers were selected in the amplification and 375 repetitive loci with 350 polymorphic loci were produced. The total average percentage of amplification loci was 93.3%. The genetic diversity of every sub.opulation was medium on （the percentage of amplification loci was 49.33%-66.67%）. The genetic diversity of high altitude samples of Zhengtiantai was lower than that of low altitude Wutonggang＇s. There was no ob.ious differentiation b.tween two sub.opulations of Zhengtiantais. The correlation is very low b.tween altitude and the amplification loci and the genetic distance, Pearson correlation coefficient was 0.431 and 0.488 （P 〈 0.01）. Through investigation, the primary cause of heredity multiplicity drops was that the hab.tat had b.en destroyed b. tourism development and other human disturb.nce.

关键词： Chimonob.mb.sa rivularis Yi DNA-RAPD sub.opulation genetic diversity altitude.

Prospective Study of Infrared-Guided Patient Setup for Fractionated Thoracic Radiation

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

International Journal of Medical Physics, Clinical Engineering and Radiation Oncology 2017年第3期6卷 313-322页

作者： Aileen b. chen Yulia Lyatskaya Joseph H. Killoran Michelle b.yd Shrooti Singh Scott Kaplin Aaron M. Allen Department of Radiation Oncology Dana-Farber Cancer Institute/Brigham and Women’s Hospital Boston MA USA Department of Radiation Oncology Davidoff Center Petach Tikvah Israel

Ob.ective: The standard practice in fractionated radiation of using of visual alignment of tattoos with weekly portal imaging for radiation setup can miss setup errors. We previously reported on the feasib.lity of using an automated infrared-guided positioning system (iGPS) for daily radiation setup. In this study, we prospectively evaluate whether use of iGPS can improve daily setup errors for patients with thoracic malignancies. Methods: Multiple external infrared markers were placed on patients undergoing thoracic radiation at the time of simulation. Patients were immob.lized using vacuum immob.lization b.g and wing-b.ard. Patients were aligned for treatment using only the iGPS system. Daily portal images were then taken, and shifts in patient position were recorded. Differences b.tween isocenter position using iGPS versus daily portal imaging were calculated. Results: Data were collected for 698 treatment sessions for 27 patients. We found that in 94.0%, 96.4%, and 93.7% of treatment sessions, isocenter position differed b.tween iGPS and daily portal imaging b. ≤5 mm in the left/right(L/R), anterior/posterior(A/P), and superior/inferior(S/I) directions, respectively. Isocenter position differed b. 5 - 10 mm in 5.7% (L/R), 3.6% (A/P), and 5.9% (S/I) of treatment sessions, and b. >10 mm in 0.3% (L/R), 0.0% (A/P), and 0.4% (S/I) of treatment sessions. Three-dimensional shifts were also calculated, with differences in isocenter position as follows: 94.9% ≤5 mm, 5.1% 5 - 10 mm, and 0.2% >10 mm. This compares favorab.y to our prior studies. Discussion: Daily treatment setup using an infrared-guided patient positioning system, correlates well with daily portal imaging and may help to improve daily treatment setup for patients with thoracic malignancies.

关键词： Radiotherapy Infrared Markers Thoracic Malignancies