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王质和他的《诗总闻》 被引量:2
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作者 郝桂敏 《沈阳师范学院学报(社会科学版)》 2001年第4期18-20,共3页
王质的《诗总闻》首创总闻体 ,丰富了解《诗》体式 ,在言《诗》中废序不观 ,其所论诗旨与《小序》有着千丝万缕的联系。在词语训释中 ,多体察细密 ,并十分注重从文学角度看待《诗经》。
关键词 王质 《诗总闻》编排特点 《体式》 《诗经》 《诗小序》 注释
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Flow Cytometric Evidence for Hydroxyl Radical-induced Apoptosis in Tobacco Protoplasts 被引量:4
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作者 雷晓勇 廖旭东 +1 位作者 张贵友 戴尧仁 《Acta Botanica Sinica》 CSCD 2003年第8期944-948,共5页
Protoplasts prepared from tobacco (Nicotiana tabacum L., cultivar BY-2) suspension cells have similar morphological characteristics to those in animal cells. The hallmarks of apoptosis such as condensation and periphe... Protoplasts prepared from tobacco (Nicotiana tabacum L., cultivar BY-2) suspension cells have similar morphological characteristics to those in animal cells. The hallmarks of apoptosis such as condensation and peripheral distribution of nuclei, TUNEL positive reaction, and DNA ladders were observed when tobacco protoplasts were treated with the hydroxyl radical generating system (1.0 mmol/L FeSO4/0.5 mmol/L H2O2). In animals, the loss of transmembrane potential (DeltaPsi(m)) and the exposure of phospholipid phosphatidylserine (PS) are believed to be the main apoptosis events. To test whether these significant processes take place in plants, flow cytometry was used to detect annexin V binding and changes in DeltaPsi(m). Results showed that the PS turned out from inner membrane and DeltaPsi(m) gradually decreased during the apoptosis. All these apoptotic characteristics proved that hydroxyl radicals can cause typical programmed cell death (PCD) in tobacco protoplasts and this design can be served as an effective experiment system to explore the mechanism of plant apoptosis. 展开更多
关键词 tobacco protoplasts flow cytometry APOPTOSIS programmed cell death (PCD) hydroxyl radicals
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Establishment of Optimized Eco-productive Paradigm in the Farming-Pastoral Zone of Northern China 被引量:10
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作者 唐海萍 张新时 《Acta Botanica Sinica》 CSCD 2003年第10期1166-1173,共8页
The farming-pastoral zone of northern China plays a dual role in ecological conditions and production and occupies an important position in the national economy. In this paper, the methodology of system engineering is... The farming-pastoral zone of northern China plays a dual role in ecological conditions and production and occupies an important position in the national economy. In this paper, the methodology of system engineering is introduced to construct and optimize an eco-productive paradigm system for the typical areas of the farming-pastoral zone. The system was constructed in the following steps: (1) design the framework of the paradigm system based on the data of physical site characteristics, biocommunities, production and economy, social culture and historical changes; (2) analyze the vegetation patterns, the interactions between vegetation and environmental factors (natural, social, economic, etc.) and the contributions of vegetation to the area, including the synthesis of the existing researches; and (3) provide the spatial arrangements of ecosystems and planning of each area, raise a comprehensive indicators of evaluation, evaluate the feasibility and soundness, and determine the optimum eco-productive paradigms for policy-makers which were land-use patterns within the threshold of ecological conservation. Three primitive paradigms of Maowusu (Mu Us) Ssandy Land, Loess Plateau and Huailai Basin in the farming-pastoral zone of northern China were proposed according to this paradigm system. 展开更多
关键词 farming-pastoral zone system engineering eco-productive paradigm system
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Plastid Inheritance in Sweet Potato as Revealed by DNA Restriction Fingerprinting 被引量:3
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作者 方晓华 张方 +1 位作者 吴乃虎 胡适宜 《Acta Botanica Sinica》 CSCD 2003年第1期73-75,共3页
The inheritance of chloroplast DNA (cpDNA) in sweet potato (Ipomoea batatas Lain.) was analyzed using DNA restriction fingerprinting. The cpDNA fingerprints of hybrids from reciprocal crosses between Xushu18 and AB78-... The inheritance of chloroplast DNA (cpDNA) in sweet potato (Ipomoea batatas Lain.) was analyzed using DNA restriction fingerprinting. The cpDNA fingerprints of hybrids from reciprocal crosses between Xushu18 and AB78-1 were found to be identical to those of their female parents, which reveals that cpDNA of sweet potato is maternally inherited in this intervarietal crossing. This maternal cpDNA transmission pattern does not accord with the putative one based on former cytological studies. The plastid inheritance in Convolvulaceae has been briefly reviewed in this study, and the utility of DNA restriction fingerprinting analysis in the study of plastid inheritance is also discussed. 展开更多
关键词 Ipomoea batatas plastid inheritance DNA restriction fingerprinting hybrids of reciprocal cross CONVOLVULACEAE
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Noisy-power dissipation and efficiency in NiO/Fe_2O_3 wet grinding by planetary ball mill 被引量:1
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作者 姚云 谢刚 +4 位作者 侯彦青 李荣兴 罗伟红 彭如振 于站良 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2014年第8期2695-2703,共9页
The relationship between the efficiency of NiO/Fe2O3 wet grinding and noisy-power dissipation was studied. The optimal grinding parameters were found as: a slurry water content of 64.10%-85.47%, ball number ratio of 3... The relationship between the efficiency of NiO/Fe2O3 wet grinding and noisy-power dissipation was studied. The optimal grinding parameters were found as: a slurry water content of 64.10%-85.47%, ball number ratio of 360/20, revolution speed of 300.9 r/min, powder-filling ratio of 10.88%, ball-filling ratio of 20.53%-23.88%, and grinding time of approximately 6 h. The discrete element method(DEM) was employed to analyze relationship between the noisy-power dissipation and the grinding efficiency, and equations describing the relationship were derived. The mean particle size of the ground powder decreased with a decrease in the degree of noisy-power dissipation, while the grinding efficiency and the amount of specific impact power used decreased with an increase in the degree of noisy-power dissipation. 展开更多
关键词 noisy-power dissipation NiO/Fe2O3 powder planetary ball mill mean particle size
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Linear Factorization of λ _polynomial Over Quaternionic Field 被引量:3
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作者 郭时光 《Chinese Quarterly Journal of Mathematics》 CSCD 2000年第2期12-16,共5页
A proof is given that any λ _polynome over real quaternionic sfield can be factorized into produce of some linear factors.By the way,some properties and applications of this factorization in matrix theory are given.
关键词 determine polynome main spectral sequence main value SINGULAR
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Ontology-based proactive knowledge system
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作者 夏士雄 张磊 +2 位作者 周勇 牛强 丁秋林 《Journal of Southeast University(English Edition)》 EI CAS 2007年第3期377-380,共4页
With the aim to address the problems presented in knowledge utilization in knowledge-intensive enterprises, the ontology-based proactive knowledge system (OPKS) is put forward to improve knowledge utilization. Proac... With the aim to address the problems presented in knowledge utilization in knowledge-intensive enterprises, the ontology-based proactive knowledge system (OPKS) is put forward to improve knowledge utilization. Proactive knowledge service is taken as the basic idea in the OPKS. The user knowledge requirement is taken as the driving factor and described by the user knowledge requirement. Ontologies are used to present the semantic of heterogeneous knowledge sources and ontology mapping is used to realize the interoperation of heterogeneous knowledge sources. The required knowledge is found by matching the user knowledge requirement with knowledge sources and is provided to the user proactively. System analysis and design of OPKS is carded on by adopting UML. The OPKS is implemented in Java language. Application in a certain institute shows that the OPKS can raise efficiency of knowledge utilization in knowledge-intensive enterprises. 展开更多
关键词 ONTOLOGY KNOWLEDGE PROACTIVE
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Influence of external nitrogen-containing donors on polymerization behavior of neodymium-based cis-1,4-polybutadiene rubber
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作者 LI Xin DONG Jing +3 位作者 HAN Zhuo-ling WANG Feng ZHANG Xue-quan LIU Heng 《合成橡胶工业》 CAS 2024年第5期438-438,共1页
Neodymium(Nd)-based catalyst in butadiene(Bd)polymerization has drawn interests due to its availability in affording higher cis-1,4-unit selectivity than transition metal(Ti,Co,Ni,etc.)-based catalysts[1-2].Such outst... Neodymium(Nd)-based catalyst in butadiene(Bd)polymerization has drawn interests due to its availability in affording higher cis-1,4-unit selectivity than transition metal(Ti,Co,Ni,etc.)-based catalysts[1-2].Such outstanding high cis-1,4-unit selecti-vity is hypothetically originated from the presence of 4 f orbitals,that can participate in monomer coordination and thereby govern subsequent enchainment manners.This unique characteristic also renders the active species highly susceptible to Lewis bases,and may impact the overall selectivity as well as polyme-rization behavior after coordination.Nevertheless,it is still a virgin area in such a field,and the influence of Lewis bases on Nd-based diene polymerizations is still a black box.Based on this consideration,how nitrogen-containing donors(D)impacts the overall behaviors of Nd-mediated Bd polymerizations is disclosed. 展开更多
关键词 POLYMERIZATION BASES SELECTIVITY
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Deformation mechanism of cold ring rolling in view of texture evolution predicted by a newly proposed polycrystal plasticity model 被引量:3
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作者 李宏伟 冯璐 杨合 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2013年第12期3729-3738,共10页
An explicit polycrystal plasticity model was proposed to investigate the deformation mechanism of cold ring rolling in view of texture evolution. The model was created by deducing a set of linear incremental controlli... An explicit polycrystal plasticity model was proposed to investigate the deformation mechanism of cold ring rolling in view of texture evolution. The model was created by deducing a set of linear incremental controlling equations within the framework of crystal plasticity theory. It was directly solved by a linear algorithm within a two-level procedure so that its efficiency and stability were guaranteed. A subroutine VUMAT for ABAQUS/Explicit was developed to combine this model with the 3D FE model of cold ring rolling. Results indicate that the model is reliable in predictions of stress-strain response and texture evolution in the dynamic complicated forming process; the shear strain in RD of the ring is the critical deformation mode according to the sharp Goss component ({110}?100?) of deformed ring; texture and crystallographic structure of the ring blank do not affect texture type of the deformed ring;texture evolves rapidly at the later stage of rolling, which results in a dramatically increasing deformation of the ring. 展开更多
关键词 cold ring rolling crystal plasticity texture evolution explicit algorithm
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Effects of Farming and Seedling-raising Methods on Population Growth and Grain Yield of Mechanized Transplanting Rice
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作者 杨波 霍晓玲 +3 位作者 吴健英 杨文婷 肖启银 任万军 《Agricultural Science & Technology》 CAS 2017年第7期1235-1239,共5页
The effects of farming method, rice variety and seedling-raising method were studied on the population growth quality and grain yield of the mechanized transplanting rice by way of three-factor split plot design. The ... The effects of farming method, rice variety and seedling-raising method were studied on the population growth quality and grain yield of the mechanized transplanting rice by way of three-factor split plot design. The results showed that the no-tillage mechanical transplanting treatment was poorer than the conventional mechanical transplanting treatment in transplanting quality in general, but the former was similar to the latter in population growth quality. In regard to grain yield, the no-tillage mechanical transplanting treatment was lower than the conventional me- chanical transplanting treatment. Raising both pot-mat seedling and plastic-tray seedling did not make much difference in population growth and grain yield of mechanized transplanting rice, so both of the seedling-raising methods can be adopted according to practical conditions. 展开更多
关键词 RICE No-tillage mechanical transplanting Seedling raising Population growth Grain yield
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Construction analysis on integral lifting of steel structure by the vector form intrinsic finite element 被引量:2
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作者 朱明亮 陈雪琪 郭正兴 《Journal of Southeast University(English Edition)》 EI CAS 2016年第4期451-456,共6页
A newnumerical method based on vector form intrinsic finite element(VFIFE) is proposed to simulate the integral lifting process of steel structures. First, in order to verify the validity of the VFIFE method, taking... A newnumerical method based on vector form intrinsic finite element(VFIFE) is proposed to simulate the integral lifting process of steel structures. First, in order to verify the validity of the VFIFE method, taking the steel gallery between the integrated building and the attached building of Nanjing M obile Communication Buildings for example, the static analysis was carried out and the corresponding results were compared with the results achieved by the traditional finite element method. Then, according to the characteristics of dynamic construction of steel structure integral lifting, the tension cable element was employed to simulate the behavior of dynamic construction. The VFIFE method avoids the iterative solution of the stiffness matrix and the singularity problems. Therefore, it is simple to simulate the complete process of steel structure lifting construction.Finally, by using the VFIFE, the displacement and internal force time history curves of the steel structures under different lifting speeds are obtained. The results show that the lifting speed has influence on the lifting force, the internal force, and the displacement of the structure. In the case of normal lifting speed, the dynamic magnification factor of 1. 5 is safe and reasonable for practical application. 展开更多
关键词 integral lifting vector form intrinsic finite element(VFIFE) steel gallery whole process of construction dynamic magnification factor
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In Vitro Fertilization in Maize and Tobacco: The Fusion Patterns During Sexual Cell Fusion 被引量:1
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作者 孙蒙祥 杨弘远 Mauro CRESTI 《Acta Botanica Sinica》 CSCD 2002年第10期1142-1145,共4页
Large scale of sexual cell fusion was carried out in order to observe the fusion pattern during in vitro fertilization with special interest in the influence of cell volume on the membrane behavior. Three patterns cou... Large scale of sexual cell fusion was carried out in order to observe the fusion pattern during in vitro fertilization with special interest in the influence of cell volume on the membrane behavior. Three patterns could be recognized in sexual cell fusion, which was supported by fluorescent microscopy with the aid of video enhanced system and cooled CCD. It was found that the fusion pattern and cell membrane behavior were related to the cell volume ratio of two fusing cells. The results reported here might be useful for interpreting and evaluating data from in vitro fertilization experiments and for explaining male cytoplasm exclusion during fertilization. 展开更多
关键词 in vitro fertilization MAIZE TOBACCO cell volume fusion pattern FITC-Con A
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Failure characteristics and its influencing factors of talus-derived rock mass during open-pit mining 被引量:1
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作者 王贵和 杨宇友 +1 位作者 张辉 张子新 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2013年第2期462-471,共10页
The failure characteristic of talus-derived rock mass continues to challenge quantitative hazard assessments in open-pit mining. Physical model test was used to assess the failure modes and mechanisms on talus-derived... The failure characteristic of talus-derived rock mass continues to challenge quantitative hazard assessments in open-pit mining. Physical model test was used to assess the failure modes and mechanisms on talus-derived rock mass. The different types of failure modes of the talus-derived rock mass were introduced and a possible failure mechanism relation between the failure zone and the structure of the talus-derived rock mass was also shown. The physical model test results indicate that the rainfall has significant influence on the stability and failure modes of talus-derived rock mass during open-pit mining. The development of the seepage area caused by rainfall initiates the localized failure in that particular area, and the initiation of localized instability is mainly induced by stress changes concentrated in the seepage area. 展开更多
关键词 talus-derived rock mass model test failure mode RAINFALL open-pit mining
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Characteristics of suspended planar-type gas sensor based on MEMS process 被引量:1
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作者 张子立 殷晨波 +1 位作者 陶春旻 朱斌 《Journal of Southeast University(English Edition)》 EI CAS 2012年第3期315-320,共6页
In order to simplify the fabrication process,distribute the temperature uniformly and reduce the power consumption of the micro-hotplate(MHP) gas sensor,a planar-type gas sensor based on SnO2 thin film with suspende... In order to simplify the fabrication process,distribute the temperature uniformly and reduce the power consumption of the micro-hotplate(MHP) gas sensor,a planar-type gas sensor based on SnO2 thin film with suspended structure is designed through a MEMS process.Steady-state thermal analysis of the gas sensor and the closed membrane type sensor where the membrane overlaps the Si substrate is carried out with the finite element model,and it is shown that the suspended planar-type gas sensor has a more homogeneous temperature distribution and a lower power consumption.When the maximum temperature on the sensor reaches 383℃,the power consumption is only 7 mW,and the temperature gradient across the thin film is less than 14℃.To overcome the fragility of the suspended beams,a novel fabrication process in which the deposition of the gas sensing film occurs prior to the formation of suspended beams is proposed.The back side of the Si substrate is etched through deep reactive ion etching(DRIE) to avoid chemical pollution of the front side.The fabrication steps in which only four masks are used for the photolithography are described in detail.The Fe doped SnO2 thin film synthesized by sol-gel spin-coating is used as the gas sensing element.The device is tested on hydrogen and exhibits satisfactory sensing performance.The sensitivity increases with the rise of the concentration from 50×10-6 to 2000×10-6,and reaches about 30 at 2000×10-6. 展开更多
关键词 gas sensor suspended planar-type micro fabrication gas sensing characteristic
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Construction of Efficient Multiple Planting Patterns of Potato for Tridimensional Climate in Subtropical Region of China 被引量:4
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作者 黄钢 沈学善 +2 位作者 屈会娟 汤永禄 袁继超 《Agricultural Science & Technology》 CAS 2013年第9期1344-1346,共3页
[Objective] The aim was to make full use of light-heat resources to expand the potato planting area on the base of ensuring the production of main grain crops and the limited arable land. [Methods] Through catch crops... [Objective] The aim was to make full use of light-heat resources to expand the potato planting area on the base of ensuring the production of main grain crops and the limited arable land. [Methods] Through catch crops, multiple cropping and intercropping, new multiple planting patterns of potato with efficiency are constructed, for the purpose of increasing yield and benefit of potato. [Result] In irrigated plain and hill area, three new planting patterns such as autumn potato/rope-rice,winter potato-rice-autumn potato, and autumn(winter) potato-rice were constructed.In dry land of plain and hill area, three new planting patterns such as spring(winter)potato/maize/sweet potato, spring(winter) potato/maize-autumn potato, and wheat + winter potato/maize/sweet potato were constructed. In plateau mountainous area, spring potato/maize was constructed. [Conclusion] With use of new planting patterns, the cropping index of new patterns was 200%-300%, while the accumulated temperature utilization was 68.9%-93.4%, light energy utilization was 0.98%-1.59% and straw utilization was 50%-100%. To compared with traditional planting patterns, the yield increased by 2.6%-93%, and benefit increased by 15.8%-284.3%. Furthermore,multiple planting patterns of potato have become main planting patterns in increasing yield and income in Sichuan. 展开更多
关键词 Tridimensional climate in subtropical region POTATO Planting pattern
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Influence of solidification mode on pore structure of directionally solidified porous Cu-Mn alloy 被引量:9
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作者 蒋光锐 李言祥 刘源 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2011年第1期88-95,共8页
By the directional solidification of metal-gas eutectic method(GASAR),porous Cu-Mn alloy with oriented pores was fabricated successfully.The variation of pore structure was studied by experiments.The results show th... By the directional solidification of metal-gas eutectic method(GASAR),porous Cu-Mn alloy with oriented pores was fabricated successfully.The variation of pore structure was studied by experiments.The results show that the pore structure is primarily dependent on the solidification mode(planar,columnar cellular,columnar dendritic,equiaxed dendritic),which is controlled by the solidification process.By numerical simulation,it is noted that along with solidification,the solidification mode of the alloy transforms from cellular to columnar dendritic and finally to equiaxed dendritic.Through increasing melt temperature and mold preheating,the range of equiaxed dendrite could be decreased,which helps to extend the region of oriented pore structure. 展开更多
关键词 porous Cu-Mn alloy solidification mode GASAR process metal-gas eutectic
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Study on the general layout of semi-submersible offshore drilling platforms based on process flow 被引量:2
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作者 岳吉祥 綦耀光 +2 位作者 肖文生 杨磊 杨轶普 《Journal of Marine Science and Application》 2009年第2期117-122,共6页
The general layout of 6th generation semi-submersible drilling platforms is the main factor impacting the efficiency of their drilling operations. This paper provides a compound/integrated algorithm based on process f... The general layout of 6th generation semi-submersible drilling platforms is the main factor impacting the efficiency of their drilling operations. This paper provides a compound/integrated algorithm based on process flow that is aimed at improving efficiency, while giving attention to stability and safety at the same time. The paper describes the process flow of dual drilling centers and a hierarchical division of rigs based on the different modes of transportation of various drilling support systems. The general layout-centripetal overall arrangement spatially was determined based on drilling efficiency. We derived our modules according to drilling functionality; the modules became our basic layout units. We applied different layout algorithm to mark out the upper and lower decks. That is, the upper deck was designed based on the lowest transportation cost while the lower deck's calculations were based on the best-fit scope. Storage configurations in columns and pontoons were also considered for the layout design. Finally the center of gravity was taken into consideration and the general layout was adjusted accordingly, to result in an optimal center of gravity. The methodology of the general layout can provide a reference for implementation of domestic designs of semi-submersible rigs. 展开更多
关键词 semi-submersible drilling platform general layout drilling process flow layout optimization group technology
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Transition of plasticity and fracture mode of Zr-Al-Ni-Cu bulk metallic glasses with network structures 被引量:1
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作者 蔡安辉 丁大伟 +4 位作者 安伟科 周果君 罗云 李江鸿 彭勇宜 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2015年第8期2617-2623,共7页
Effect of network structure on plasticity and fracture mode of Zr?Al?Ni?Cu bulk metallic glasses (BMGs) was investigated. The microstructures of transversal and longitudinal sections were exposed by chemical etch... Effect of network structure on plasticity and fracture mode of Zr?Al?Ni?Cu bulk metallic glasses (BMGs) was investigated. The microstructures of transversal and longitudinal sections were exposed by chemical etching and observed by scanning electron microscopy (SEM). The mechanical properties were examined by room-temperature uniaxial compression test. The results show that both plasticity and fracture mode are significantly affected by the network structure and the alteration occurs when the size of the network structure reaches up to a critical value. When the cell size (dc) of the network structure is ~3μm, Zr-based BMGs characterize in plasticity that decreases with increasingdc. The fracture mode gradually transforms from single 45° shear fracture to double 45° shear fracture and then cleavage fracture with increasingdc. In addition, the mechanisms of the transition of the plasticity and the fracture mode for these Zr-based BMGs are also discussed. 展开更多
关键词 bulk metallic glass PLASTICITY fracture mode network structure
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Parallel Implementation of Global Illumination Using PVM
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作者 孙济洲 Nicolas D Georganas 《Transactions of Tianjin University》 EI CAS 2002年第3期178-182,共5页
In this paper an attempt of employing network resources to solve a complex and time-consuming problem is presented. The global illumination problem is selected as the study objective. An improved density estimation al... In this paper an attempt of employing network resources to solve a complex and time-consuming problem is presented. The global illumination problem is selected as the study objective. An improved density estimation algorithm is first developed, in which the more inherent concurrency is explored. Then its parallel implementation by using a PVM mechanism and the running performance analysis are provided. The analysis results show the expected speed-up obtained and demonstrate that the PVM has good application prospects for parallel computation in a distributed network. 展开更多
关键词 parallel computation parallel virtual machine(PVM) global illumination distributed network
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Strategies of Teaching English Poetry
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作者 纪启明 李明 《Sino-US English Teaching》 2007年第3期18-20,29,共4页
This paper deals with how to teach appreciation of English poetry in college by analyzing the following items: introduction of the concept, content and writing style, the realistic meaning, multi-media aided teaching... This paper deals with how to teach appreciation of English poetry in college by analyzing the following items: introduction of the concept, content and writing style, the realistic meaning, multi-media aided teaching and translating English poetry into Chinese. 展开更多
关键词 appreciation of English poetry content and writing style the realistic meaning multi-media aided teaching translating English poetry into Chinese
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