中国的高性能混凝土技术

中国高性能混凝土的强度等级一般为Ｃ６０。Ｃ８０的高性能混凝土在试点工程中也得到了应用。中国高性能混凝土具有以下特色：（１）矿物质超细粉生产与应用：包括矿渣、磷渣、天然沸石、粉煤灰等，比表面积６０００～８０００ｃｍ２／ｇ。以粉体取代混凝土中的部分水泥，改善混凝土的和易性，提高耐久性和强度。（２）载体效应的利用与坍落度损失的控制：利用无机粉体为载体，吸附高效减水剂与缓凝剂；将这种吸附了高效减水剂的粉体，再与混凝土一起拌合时，能缓慢地将减水剂释放到混凝土拌合物中，控制坍落度在１．５～２．０ｈ无损失。（３）电化学方法的有效应用：通过电化学方法测定Ｃｌ－在ＨＰＣ中的扩散系数，检测ＨＰＣ中的钢筋锈蚀，以及对钢筋的电化学保护等。为了进一步提高ＨＰＣ的性能，中国正在努力解决ＨＰＣ由于自收缩引起的裂纹及进一步水化引起的裂纹，以及解决其脆性等问题。     

用聚合酶链反应检测HBVDNA敏感性的探讨

本实验用聚合酶链反应（ＰＣＲ）技术对５６例受检者进行乙肝病毒（ＨＢＶ）ＤＮＡ检测，并将结果与血清标志物检测结果比较，结果表明，在ＨＢｓＡｇ、ＨＢｅＡｇ和抗ＨＢｃＡｇ同时阳性的受检者中，１００％可检测出ＨＢＶＤＮＡ。在血清标志物全阴性受检者中，也有４５％可测出ＨＢＶＤＮＡ。结合其他血清标志物的检测结果，说明用ＰＣＲ技术检测ＨＢＶＤＮＡ是敏感的，在临床应用上也是可行的。     

结构混凝土耐久性无损检测技术

对结构混凝土进行耐久性检测、评估是掌握结构实际状况、制订修复或维护策略的基础,对延长以混凝土结构为主体的基础设施使用寿命具有重大的实际意义.综述了既有混凝土结构耐久性检测的主要内容,并对混凝土渗透性、钢筋锈蚀情况等影响结构耐久性的关键参数的无损检测技术进行了介绍.     

混凝土渗透性的影响因素及改善措施

混凝土的渗透性是影响混凝土耐久性的重要因素。介绍了混凝土渗透机理及混凝土渗透性电学评价。详细讨论了混凝土渗透性的影响因素及改善措施。     

用PCR法检测人巨细胞病毒DNA

用聚合酶链式反应（ＰＣＲ）法检测患者尿液中人巨细胞病毒（ＨＣＭＶ）ＤＮＡ．结果表明，自行设计合成的引物位于ＨＣＭＶ基因组早期蛋白基因区，经ＰＣＲ仪扩增一段长４３０ｂｐ的特异序列片段，对正常人基因组ＤＮＡ或其它疱疹病毒ＤＮＡ无交叉反应．此法可检测出少至１０－１６ｇ（０．１ｆｇ）的病毒ＤＮＡ．通过对３５份尿液标本的检测，比较ＰＣＲ法和组织培养法的检测结果完全一致     

电化学除氯后混凝土性能试验研究

电化学除氯是短期内有效去除遭受氯盐污染的混凝土中氯离子的技术,可增强结构耐久性并提高使用寿命,但电化学除氯后混凝土性能会发生变化.对电化学除氯后混凝土的性能进行了试验研究,内容包括除氯对混凝土抗压强度、钢筋与混凝土的粘结强度、混凝土渗透性和混凝土中剩余氯离子含量的影响.结果表明:在本试验所控制的除氯参数下,除氯对混凝土的抗压强度有一定影响,混凝土的密实性和抗氯离子渗透性能有所提高,钢筋与混凝土的粘结强度随电流密度和电量有不同程度的降低.     

HSC水泥快硬增强剂的试验研究

使用ＨＳＣ增强剂，可使混凝土各个龄期的强度显著增加，而其成本却比普通混凝土降低１５％左右。同时，使用ＨＳＣ可明显改善混疑土的物理性能，使混凝土耐久性得到保障。现已开发出第三代产品ＨＳＣ－Ⅲ，用它配制的混凝土标号可达Ｃ１００，为我国发展高强混凝土作出了贡献     

浅谈建筑工程混凝土结构检测

混凝土结构检测技术是建筑工程结构检测的我重要组成部分,混凝土结构的强度和耐久性是建筑工程质量的重要保障之一,本文概述了混凝土技术的历史发展和技术应用,并对混凝土结构检测的前景进行了大胆的预测。     

浅谈桥梁混凝土的耐久性

桥梁的安全性和耐久性一直是业内关注的焦点，而影响桥梁安全性和耐久性的因素很多，是一个系统工程。这里结合笔者的一些认识，浅谈一下影响桥梁混凝土耐久性的因素，以期抛砖引玉。     

高强高性能混凝土配合比设计初探

高强高性能混凝土是近年发展起来的一种新型混凝土。具有高强，高流动性，高耐久性，高体积稳定性和良好的经济性等技术性能。一直被广大科研和工程技术人员重视，普遍认为是21世纪混凝土技术发展的趋势。本文通过理论分析和经验，提出了高强高性能混凝土组成的配合比设计方法，为其在土木工程中的应用提供了有利的依据和有力的保证。     

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.     

An Analysis of Catherine＇s Character——Wuthering Heights

Wuthering Heights, Emily Bronte＇s only novel, was published in December of 1847 under the pseudonym Ellis Bell. The book did not gain immediate success, but it is now thought one of the finest novels in the English language. Catherine is the key character of this masterpiece, because everybody and everything center on her though she had a short life. We can understand this masterpiece better if we know Catherine well.     

Lower Paleozoic oil relationships within Williston Basin, Canada

The Williston Basin is a significant petroleum province, containing oil production zones that include the Middle Cambrian to Lower Ordovician, Upper Ordovician, Middle Devonian, Upper Devonian and Mississippian and within the Jurassic and Cretaceous. The oils of the Williston Basin exhibit a wide range of geochemical characteristics defined as "oil families", although the geochemical signature of the Cambrian Deadwood Formation and Lower Ordovician Winnipeg reservoired oils does not match any "oil family". Despite their close stratigraphic proximity, it is evident that the oils of the Lower Palaeozoic within the Williston Basin are distinct. This suggests the presence of a new "oil family" within the Williston Basin. Diagnostic geochemical signatures occur in the gasoline range chromatograms, within saturate fraction gas chromatograms and biomarker fingerprints. However, some of the established criteria and cross-plots that are currently used to segregate oils into distinct genetic families within the basin do not always meet with success, particularly when applied to the Lower Palaeozoic oils of the Deadwood and Winnipeg Formation.     

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.     

Design and analysis of generic LBS application developing platform

Location based services is promising due to its novel working style and contents.A software platform is proposed to provide application programs of typical location based services and support new applications developing efficiently. The analysis shows that this scheme is easy implemented, low cost and adapt to all kinds of mobile nework system.     

橡胶颗粒沥青混合料低温抗裂性试验研究

以AC-13级配为基础,将橡胶颗粒代替部分集料掺入混合料中,以低温弯曲试验为评价方法对不同橡胶颗粒掺量下沥青混合料的低温抗裂性进行研究,并引入应变能密度值对混合料的低温抗裂性进行综合评价.试验结果表明:橡胶颗粒沥青混合料试件的破坏微应变均超过2 300,满足冬寒区的技术指标;无论是否掺加橡胶颗粒,随着温度的下降,沥青混合料破坏时的最大弯拉强度增大,弯拉应变降低,劲度模量增大;弯曲应变能密度在胶粒掺量为1%左右时具有较大的弯曲应变能密度值,此时橡胶颗粒沥青混合料具有较好的低温抗裂性.     

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-