超细氧化铋的制备与结构特性

采用弱碱液相沉淀－灼烧法制备了超细氧化铋粉末，该法具有流程简单、引入杂质少、灼烧温度低、产品纯度高（９９．９％以上）、粒度细（平均粒径０．０２μｍ）、性能优越等特点，很值得研究和开发．     

碳酸钙补强的抗血栓材料成型工艺

研究了用超细碳酸钙补强的聚氨酯－肝素接枝共聚材料的成型工艺。采用低温等离子体接枝技术,肝素以共价键形式直接固定在聚氨酯材料制成人工器官内壁。经ＤＳＣ和ＴＧ对碳酸钙补强的聚氨酯溶液和纯聚氨酯溶液的热分析知,最佳加热温度１００℃,保温时间：在玻璃凸模上浸渍所得第一层聚氨酯溶液需烘５５ｍｉｎ;此后再次复层的溶液需烘９０ｍｉｎ。经全血凝固时间的检测,聚氨酯－肝素接枝共聚体界面具有显著的抗凝血功能。     

新型肝素化聚氨酯膜的制备与研究

通过两步溶液聚合法合成表面含有羧基的聚氨酯（PU）,并用1-乙基-3-（二甲基丙胺）碳二亚胺（WSC）对聚氨酯表面羧基进行活化后,在4℃下柠檬酸钠缓冲液中与肝素上氨基反应得到表面共价键接枝的肝素化聚氨酯膜。通过甲苯胺蓝染色法、红外光谱法等对肝素化前后结构特征进行表征,用静态水接触角、体外抗凝血性测试其生物相容性。结果表明：在pH=5.0的肝素柠檬酸钠缓冲液中反应96 h,聚氨酯表面肝素接枝率最高,接枝量达到1.92μg/cm^2;同时,共价接枝肝素后接触角从61°降低到44°,并且抗凝血性能得到明显的改善。     

肝素化聚氨酯作为药物洗脱支架涂层材料

以聚碳酸酯二元醇(PCDL)为软段,4,4′-二苯基亚甲基二异氰酸酯(MDI)为硬段,二羟甲基丙酸(bis-MPA)为扩链剂合成了侧链含羧基的聚碳酸酯型聚氨酯。聚氨酯表面经1-乙基-(3-二甲基氨基丙基)碳酰二亚胺盐酸盐(EDAC)活化后接枝肝素分子,得到肝素化聚氨酯材料。经测定,材料表面肝素接枝量达到1.92μg/cm2,聚合物亲水性明显提高,体外蛋白质黏附实验显示肝素化聚氨酯抑制蛋白质吸附的能力较肝素化之前明显提高。动物实验表明肝素化聚氨酯作为支架涂层材料对血管壁的炎性刺激明显低于未肝素化材料,有望成为一种理想的冠状动脉支架涂层材料。     

聚氨酯中心静脉导管表面接枝聚维酮碘及抗菌性能研究

利用紫外光接枝技术,在聚氨酯中心静脉导管表面接枝聚乙烯基吡咯烷酮(聚维酮,PVP),再与碘络合,得到表面接枝聚维酮碘(PVP-I)的改性聚氨酯中心静脉导管(PU-g-PVP-I).将这种表面改性的中心静脉导管加到同样体积的液体培养基中,分别接种大肠杆菌、金黄色葡萄球菌、白色葡萄球菌和蜡状芽孢杆菌四种菌体,恒温培养15 ～ 18 h后得到抗菌性能曲线;结果表明,PU-g-PVP-I具有持久、广谱、高效的抗菌作用.     

超细粉末材料改性水玻璃粘结剂

从几种可能的超细材料里面筛选出一种最合适的超细材料,就这种材料对水玻璃粘结剂的具体性能影响展开研究.结果表明:用经过特殊处理后的超细粉末材料改性水玻璃粘结剂,具有常温强度高、残留强度低等优点;超细粉末材料改性的水玻璃粘结剂采用酯硬化工艺,可使水玻璃粘结剂的加入量低于3.0%,在水玻璃砂常温强度有所提高的前提下,其溃散性显著改善.较佳的超细粉末材料改性水玻璃粘结剂的测试结果为(与不改性水玻璃相比):常温24h强度提高了30.7%,残留强度下降了40.1%.     

聚合物接枝改性超细二氧化硅表面状况及形成机理

在超细二氧化硅表面复合接枝聚合改性工艺的基础上,对改性前后超细二氧化硅的表面状况进行了研究,证明通过该工艺能够实现对超细二氧化硅表面接枝聚合改性,能够有效分散超细二氧化硅聚集体,其原因是苯乙烯与预先接枝在超细二氧化硅表面上硅烷偶联剂的双键发生了自由基聚合反应。该改性工艺增强了无机粉体表面改性的针对性。     

利用辐射接枝技术改善聚氨酯的血液相溶性

为改善材料的生物相溶性,将亲水性单体甲基丙烯酸β—羟乙酯辐射接枝到聚氨酯管材上。将聚氨酯在单体中预溶胀然后辐照,通过控制聚氨酯在单体中的溶胀度和照射剂量调节接枝层的深度和接枝率。接枝聚氨酯的亲水性随接枝率的增大明显改善。抗血栓试验表明与未接枝聚氨酯和医用硅橡胶比较,接枝聚氨酯有良好的血液相溶性。     

具有纳米质点性质的MFI型硅沸石微细晶粒的合成及表征

分别以白炭黑和硅溶胶为硅源，在（ＴＰＡ）２Ｏ－Ｎａ２Ｏ－ＳｉＯ２－Ｈ２Ｏ体系中，反应温度为６０℃．，合成了高结晶度纯硅沸石，用扫描电子显微镜法测得的晶业大小分别为０．２０μｍ和０．４５μｍ；用粉末Ｘ射线衍射线宽法测得的晶粒大小为０．０２μｍ。与高温合成的硅沸石样品相比较，低温合成的微细晶粒硅沸石样品已具备纳米级产若干特性。     

提高聚氯乙烯与丁苯橡胶共混相容性的研究

通过加入各种增容剂（Ｃｏｍｐａｔｉｂｉｌｉｚｅｒ）和采用粉末丁苯橡胶（ＰＳＢＲ）及经接枝、交联改性的粉末丁苯橡胶（ＰＭＳＢＲ），研究了提高聚氯乙烯／丁苯橡胶（ＰＶＣ／ＳＢＲ）共混相容性的途径。物理机械性能测试结果表明：五种增容剂对软质ＰＶＣ／ＳＢＲ共混物的改性效果以粉末丁腈Ｐ８３和丁腈－２６（ＮＢＲ－２６）最佳；粉末橡胶对ＰＶＣ的改性效果优于块状橡胶，ＰＭＳＢＲ对软质ＰＶＣ的改性效果优于以ＮＢＲ－２６作增容剂的块状ＳＢＲ和ＰＳＢＲ；用不同改性方法制得的四种ＰＭＳＢＲ中，以多层乳液接枝改性的ＰＭＳＢＲ－４对ＰＶＣ的改性效果最佳，用它改性硬质ＰＶＣ的缺口抗冲击强度和软质ＰＶＣ的耐寒性，效果皆超过粉末丁腈Ｐ８３。扫描电镜、透射电镜和动态力学谱分析表明：ＰＶＣ／ＰＭＳＢＲ－４共混材料呈良好的韧性断裂，橡胶粒子分散较均匀，相界面模糊，低温Ｔｇ升高，说明ＰＶＣ／ＳＢＲ的相容性获得显著提高     

Markedness and its Interpretation in Language Use

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.     

Features of Women's language

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.     

Characterization of Ordovician carbonate reservoirs, southeastern Saskatchewan, Canada

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.     

低渗透非均质砂岩油藏启动压力梯度研究

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。     

On Tragic Consciousness In The Works By Ernest Hemingway

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.     

A computer generator for randomly layered structures

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

An Index mechanism for multi-scale view in spatial databases

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.     

Jane Eyre——A Feminist In The 19th Century

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.     

Achieving Unusual States of Matter Under High Pressure

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-     

Exchange-Correlation and Electronic Excitation Energies from Pairing Matrix Fluctuations

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-