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1.
采用扫描电子显微镜(SEM)对聚丙烯(PP)和PP,高密度聚乙烯(HOPE)乙丙橡胶(EPR)共混体(高分子合金)的微观形态进行了观察和分析,并探讨了EPR含量对微观形态及冲击强度的影响。实验表明,加入EPR使共混体比纯PP的冲击强度提高16倍以上。  相似文献   

2.
EPR思维研究中的若干问题   总被引:1,自引:0,他引:1  
论述了EPR论文提出的背景。回顾了1985年在BBC举行的科学讨论,并提出了今天仍需要做深入研究的有关问题。指出狭义相对论(SR)与EPR思维在思想体系方面的一致性,它们关系到合理的自然观和宇宙观的建立,而超光速的可能性问题成为它们与量子力学(QM)矛盾的焦点。叙述了与EPR思维直接相关的量子信息学的发展。认为应深入研究EPR才能消除神秘感。  相似文献   

3.
EPR法研究了Ti(OBu),Ti(OBu)_3Cl,Ti(OBu)_2Cl_2,Ti(OBu)Cl_3和MgCl_2-n-BuOH-Ti(OBu)_4,MgCl_2-n-BuOH-Ti(OBu)_4-TiCl_4,MgCl_2-n-BaOH-SiCl_4-TiCl_4分别与Al(i-Bu)_3相互作用的结果表明,载体及配位体的特性都会影响到中心Ti~(3+)离子的EPR特征。通过干燥氯化氢处理和添加电子给予体改善了催化剂晶体结构规整性,表观上呈现对称性较好的EPR谱,在丙烯聚合时相应地表现出较高的定向性。  相似文献   

4.
Large-strain deformation by single electroplastic rolling (EPR) was imposed on AZ31 magnesium alloy strips. During EPR at low temperature (150-250℃), numerous twins formed in the alloy. After EPR at a high temperature (350℃), the number of twins reduced and some dynamic recrystallization (DRX) grains formed at grain boundaries and twinned regions. The synergic thermal and athermal effects generated by electropulsing, which promoted dislocation motion, induced a few small DRX grains, and ductile bandings were mainly responsible for large-strain deformation during EPR. The inclination angle of the basal pole stemmed from the counterbalance of the inclination direction of the basal pole between the DRX grains and deformed coarse grains.  相似文献   

5.
钛-镁体系烯烃聚合催化剂中钛离子状态的EPR研究   总被引:1,自引:0,他引:1  
利用EPR法研究了MgCl_2-n-BuOH-SiCl_4-TiCl_4/Al(i-Bu)_3体系催化剂中钛离子的状态,发现催化剂体系中存在(Ⅰ)、(Ⅱ)、(Ⅲ)和(Ⅳ)四种类型的Ti~(3 )离子的顺磁物类,其EPR信号分别为g=1.99,g_Δ=1.97,g_Δ=1.95和g_Δ=1.88,前三者为处于不同畸变配体场中的非烷基化Ti~(3 )离子,在烯烃聚合中不起活性中心作用.带有Cl空配位的烷基化Ti~(3 )离子是活性的物类,但其中只有少部分呈弧立状态的(Ⅳ)型离子对EPR有贡献,大部分可能通过氯桥键合,在MgCl_2表面上形成聚集体或TiCl_3分散粒子而成为EPR无声的物类.  相似文献   

6.
为促进我国生产者延伸责任制(extended producer responsibility,简称EPR)的有效实施,重点研究了EPR实施过程中政府与企业的核心作用,分析了二者间博弈和策略寻优过程对实施EPR的影响,构建了两主体完全信息静态EPR博弈模型.通过对博弈的短期收益与长期收益的交叉分析,识别出政府实施EPR的成本、对企业不承担责任的惩罚、企业承担责任的成本、不承担责任受到惩罚或潜在收益、企业形象价值以及国际合作与国际市场开发等因素是影响EPR构建与实施的关键因素.据此,结合我国国情,剖析了我国现阶段实施EPR的运行环境特点,为政府部门以及相关行业企业提出对策建议.  相似文献   

7.
Large-strain deformation by single electroplastic rolling(EPR) was imposed on AZ31 magnesium alloy strips. During EPR at low temperature(150–250°C), numerous twins formed in the alloy. After EPR at a high temperature(350°C), the number of twins reduced and some dynamic recrystallization(DRX) grains formed at grain boundaries and twinned regions. The synergic thermal and athermal effects generated by electropulsing, which promoted dislocation motion, induced a few small DRX grains, and ductile bandings were mainly responsible for large-strain deformation during EPR. The inclination angle of the basal pole stemmed from the counterbalance of the inclination direction of the basal pole between the DRX grains and deformed coarse grains.  相似文献   

8.
宣文 《上海信息化》2016,(12):20-22
在刚刚落下帷幕的第十八届工博会上,斩获金奖的EPR核电蒸汽发生器成为产业界和资本市场关注的焦点.EPR核电蒸汽发生器由法国AREVA公司设计,是我国首套完全自主化制造、建设的三代EPR(压水堆型)核电机组,上海电气核电设备有限公司(以下简称“上核”)在以往蒸汽发生器研制经验基础上,依靠自身的人员、技术、装备,通过科研立项、专题攻关、工艺试验、技术创新,完全掌握了EPR蒸汽发生器制造技术,循着“抢占世界核电制造高地”的国家战略迈出了坚实的一步.  相似文献   

9.
用对角化完全能量矩阵方法和微扰方法计算了分别由辛基胺(R3N, TOA)和辛基磷化物(R3PO, TOPO)二种物质在盐酸溶液中萃取的四角V4+离子化合物的光谱带和电子顺磁共振(EPR)参量. 计算结果表明, 由这二种微观理论方法计算的光谱带和EPR参量不仅互相非常接近, 而且也与实验值较好的符合. 这说明人们可以用这二种方法来研究固体中3d1过渡金属离子基团的光谱和EPR谱.  相似文献   

10.
<正> 深圳中冠印染股份有限公司(000018)企业资源计划系统(EPR)近日通过了鉴定验收,这也是国内纺织印染行业首家通过验收的EPR系统。深中冠总经理孙志平说,EPR系统是将公司的物流、信息流、资金流结合在一起形成的管理平台。该系统将生产订单、工艺流程、成品检验、成本核算、仓库管理、客户关系、信息传输等方面的数据,纳入系统管理之中,实行适时全程控股。  相似文献   

11.
Language markedness is a common phenomenon in languages, and is reflected from hearing, vision and sense, i.e. the variation in the three aspects such as phonology, morphology and semantics. This paper focuses on the interpretation of markedness in language use following the three perspectives, i.e. pragmatic interpretation, psychological interpretation and cognitive interpretation, with an aim to define the function of markedness.  相似文献   

12.
何延凌 《科技信息》2008,(4):258-258
Language is a means of verbal communication. People use language to communicate with each other. In the society, no two speakers are exactly alike in the way of speaking. Some differences are due to age, gender, statue and personality. Above all, gender is one of the obvious reasons. The writer of this paper tries to describe the features of women's language from these perspectives: pronunciation, intonation, diction, subjects, grammar and discourse. From the discussion of the features of women's language, more attention should be paid to language use in social context. What's more, the linguistic phenomena in a speaking community can be understood more thoroughly.  相似文献   

13.
The discovery of the prolific Ordovician Red River reservoirs in 1995 in southeastern Saskatchewan was the catalyst for extensive exploration activity which resulted in the discovery of more than 15 new Red River pools. The best yields of Red River production to date have been from dolomite reservoirs. Understanding the processes of dolomitization is, therefore, crucial for the prediction of the connectivity, spatial distribution and heterogeneity of dolomite reservoirs.The Red River reservoirs in the Midale area consist of 3~4 thin dolomitized zones, with a total thickness of about 20 m, which occur at the top of the Yeoman Formation. Two types of replacement dolomite were recognized in the Red River reservoir: dolomitized burrow infills and dolomitized host matrix. The spatial distribution of dolomite suggests that burrowing organisms played an important role in facilitating the fluid flow in the backfilled sediments. This resulted in penecontemporaneous dolomitization of burrow infills by normal seawater. The dolomite in the host matrix is interpreted as having occurred at shallow burial by evaporitic seawater during precipitation of Lake Almar anhydrite that immediately overlies the Yeoman Formation. However, the low δ18O values of dolomited burrow infills (-5.9‰~ -7.8‰, PDB) and matrix dolomites (-6.6‰~ -8.1‰, avg. -7.4‰ PDB) compared to the estimated values for the late Ordovician marine dolomite could be attributed to modification and alteration of dolomite at higher temperatures during deeper burial, which could also be responsible for its 87Sr/86Sr ratios (0.7084~0.7088) that are higher than suggested for the late Ordovician seawaters (0.7078~0.7080). The trace amounts of saddle dolomite cement in the Red River carbonates are probably related to "cannibalization" of earlier replacement dolomite during the chemical compaction.  相似文献   

14.
理论推导与室内实验相结合,建立了低渗透非均质砂岩油藏启动压力梯度确定方法。首先借助油藏流场与电场相似的原理,推导了非均质砂岩油藏启动压力梯度计算公式。其次基于稳定流实验方法,建立了非均质砂岩油藏启动压力梯度测试方法。结果表明:低渗透非均质砂岩油藏的启动压力梯度确定遵循两个等效原则。平面非均质油藏的启动压力梯度等于各级渗透率段的启动压力梯度关于长度的加权平均;纵向非均质油藏的启动压力梯度等于各渗透率层的启动压力梯度关于渗透率与渗流面积乘积的加权平均。研究成果可用于有效指导低渗透非均质砂岩油藏的合理井距确定,促进该类油藏的高效开发。  相似文献   

15.
As an American modern novelist who were famous in the literary world, Hemingway was not a person who always followed the trend but a sharp observer. At the same time, he was a tragedy maestro, he paid great attention on existence, fate and end-result. The dramatis personae's tragedy of his works was an extreme limit by all means tragedy on the meaning of fearless challenge that failed. The beauty of tragedy was not produced on the destruction of life, but now this kind of value was in the impact activity. They performed for the reader about the tragedy on challenging for the limit and the death.  相似文献   

16.
AcomputergeneratorforrandomlylayeredstructuresYUJia shun1,2,HEZhen hua2(1.TheInstituteofGeologicalandNuclearSciences,NewZealand;2.StateKeyLaboratoryofOilandGasReservoirGeologyandExploitation,ChengduUniversityofTechnology,China)Abstract:Analgorithmisintrod…  相似文献   

17.
There are numerous geometric objects stored in the spatial databases. An importance function in a spatial database is that users can browse the geometric objects as a map efficiently. Thus the spatial database should display the geometric objects users concern about swiftly onto the display window. This process includes two operations:retrieve data from database and then draw them onto screen. Accordingly, to improve the efficiency, we should try to reduce time of both retrieving object and displaying them. The former can be achieved with the aid of spatial index such as R-tree, the latter require to simplify the objects. Simplification means that objects are shown with sufficient but not with unnecessary detail which depend on the scale of browse. So the major problem is how to retrieve data at different detail level efficiently. This paper introduces the implementation of a multi-scale index in the spatial database SISP (Spatial Information Shared Platform) which is generalized from R-tree. The difference between the generalization and the R-tree lies on two facets: One is that every node and geometric object in the generalization is assigned with a importance value which denote the importance of them, and every vertex in the objects are assigned with a importance value,too. The importance value can be use to decide which data should be retrieve from disk in a query. The other difference is that geometric objects in the generalization are divided into one or more sub-blocks, and vertexes are total ordered by their importance value. With the help of the generalized R-tree, one can easily retrieve data at different detail levels.Some experiments are performed on real-life data to evaluate the performance of solutions that separately use normal spatial index and multi-scale spatial index. The results show that the solution using multi-scale index in SISP is satisfying.  相似文献   

18.
In the 19th century the society was controlled by men, and women were just appendants of them, they had not any rights and freedom. But Jane was an exception, she showed some characteristics of early feminist. Jane showed her characteristics of feminism in three aspects: rebellion, equality, and independence. These characteristics were helpful to her success, and feminism is the only way out for women of that time.  相似文献   

19.
正The periodicity of the elements and the non-reactivity of the inner-shell electrons are two related principles of chemistry,rooted in the atomic shell structure.Within compounds,Group I elements,for example,invariably assume the+1 oxidation state,and their chemical properties differ completely from those of the p-block elements.These general rules govern our understanding of chemical structures and reactions.Using first principles calcula-  相似文献   

20.
We have developed an adiabatic connection to formulate the ground-state exchange-correlation energy in terms of pairing matrix linear fluctuations.This formulation of the exchange-correlation energy opens a new channel for density functional approximations based on the many-body perturbation theory.We illustrate the potential of such approaches with an approximation based on the particle-particle Random Phase Approximation(pp-RPA).This re-  相似文献   

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