矿物掺和料提高混凝土强度的机理分析

根据设计要求,结合原材料研究了矿物掺和料对混凝土工作性能和力学性能的影响。发现掺加粉煤灰或矿渣能明显提高混凝土的工作性,本文着重从五个方面阐述分析了矿物掺和料对提高混凝土强度的作用机理。     

大掺量矿物掺合料在商品混凝土中的应用

本文作者阐述了大掺量矿物掺和料在混凝土的应用可以减少水泥用量，能够很大程度的改善大气环境，论述了目前混凝土中所掺加的矿物掺合料的种类以及发展方向；通过大掺量矿物掺合料的混凝土配合比设计，确定了矿物掺和料的适宜掺量和系列混凝土配合比，并且在新世界工程中实际应用，混凝土和易性．混凝土强度以及裂缝控制方面都取得了较好的成果；另外，提出了商品混凝土搅拌站在使用大掺量矿物掺和料时，需要注意的问题，比如应该延长混凝土搅拌时间，应该指导施上观场采取及时、适宜的养护措施等。     

外加剂和掺和料对混凝土弹性模量的影响分析

介绍了外加剂（单掺）技术和外加剂与活性矿物掺和料（双掺）技术的特点,测出了不同龄期混凝土抗压强度与弹性模量的对应关系,查明了所用外加剂掺和料混凝土增强早强的发展规律。     

结构用橡胶轻集料混凝土的性能实验研究

针对橡胶轻集料混凝土的基本力学性能进行了试验研究,通过对不同橡胶集料掺量、水泥用量和不同矿物掺和料的轻集料混凝土基本性能的研究,结果表明在普通轻集料混凝土中掺入一定质量的橡胶微粒可以有效的改善轻集料在混凝土中的分布状况,通过调整橡胶集料的含量和加入一定质量的矿物掺和料可以配制出和易性、坍落度均优且强度满足CL30的结构用橡胶轻集料混凝土.     

GH矿粉对粉煤灰混凝土的增强效果

通过成型胶砂试件和混凝土试件，对提高大掺量粉煤灰高性能混凝土早期强度的方法进行了试验研究．试验所用的GH矿粉是以炼铁厂的工业炉尘为基料、配以若干种具有互补性能的化工原料经特殊处理复合而成的混凝土掺和料，GH矿粉和粉煤灰的用量分别为胶凝材料总量的10％～15％和20％～60％．研究结果表明，用GH矿粉和Ⅱ级粉煤灰复合作为掺和料，可显提高大掺量粉煤灰混凝土的强度，尤其是早期强度，其增强效果甚至优于硅灰．用240kg／m^3 42．5级普通硅酸盐水泥、240kg／m^3 Ⅱ级粉煤灰和60kg／m^3 GH掺和料，配制出了28d强度为106MPa的高性能粉煤灰混凝土，并使混凝土成本显降低．     

西部地区高性能混凝土的强度影响因素研究

针对西部地区严酷环境条件，制备了214组不同配合比的混凝土，并研究了水胶比、水泥用量、矿物掺和料和养护龄期对高性能混凝土强度的影响规律。结果表明：配制强度等级C40以上的混凝土，其W／B必须小于0．4；W／B=0．4时，水泥用量不宜超过500kg／m^3；矿物掺合料的品种及掺量的变化对混凝土工作性和强度的影响很大；随养护龄期增长，掺矿物掺合料的混凝土在后期强度增长较快。     

粉煤灰在混凝土应用中的性能探究

粉煤灰作为一种活性掺和料,主要应用于混凝土中,并在公路工程中被广泛和普遍的应用。本文主要介绍粉煤灰在混凝土使用中对水泥混凝土性能的改善及其副作用。     

盐沼泽环境下公路桥梁桩基材料耐腐蚀试验

为解决盐沼泽环境下桥梁桩基础混凝土材料的耐久性,通过分别埋置在现场地表、水中、地下0.25m深和地下1.25m深的13个不同配合比的混凝土试件,历时360d的自然条件盐碱腐蚀环境下公路桥梁桩基混凝土材料腐蚀试验,系统地研究了掺和料(粉煤灰、矿粉、硅灰、膨胀剂、水泥基自愈合防水材料)种类及阻锈剂、抗硫酸盐水泥、钢护筒等对公路桥梁桩基混凝土抗侵蚀性能的影响,分别测试了混凝土立方体抗压强度和质量;采用扫描电镜、能谱仪和X衍射仪对混凝土进行微观分析,进而揭示其内部腐蚀机理;并提出混凝土抗侵蚀系数随龄期变化的回归公式。研究结果表明:埋置条件对混凝土抗侵蚀性能有一定影响,4种埋置条件中,放置在地表上的混凝土受侵蚀最严重,埋置在土中1.25m深处的混凝土腐蚀最轻,但不同混凝土试件略有差别;矿物掺和料的合理搭配能有效提高混凝土的抗侵蚀性能,其中矿渣应与膨胀剂掺和(CMP3),粉煤灰应与硅灰掺和(CMP7),水泥基自愈合防水材料应与硅灰掺和(CMP9);几种情况下360d内混凝土抗侵蚀系数均在0.85以上,具有较好的抗侵蚀性能;钢筋阻锈剂对混凝土的抗侵蚀性能有负面影响;所得回归公式可为混凝土耐久性的预测提供参考;腐蚀产物中发现了钙矾石、方解石、Friedel盐和硅灰石膏,这些腐蚀产物共同作用加速了混凝土的腐蚀;粉煤灰中活性成分Al_2O_3较高时,会加速钙矾石的生成,对混凝土不利。     

矿物掺和料对混凝土抗氯离子渗透性能的影响

本文根据跨海大桥的设计要求,重点研究了各种矿物掺和料掺量与配伍对海工混凝土抗氯离子渗透性能的影响,发现双掺粉煤灰和矿渣或三元复掺粉煤灰-矿渣-硅灰能显著提高海工混凝土的抗氯离子渗透性能,高钙粉煤灰海工混凝土抗氯离子渗透性能的改善作用比低钙粉煤灰强。     

生活垃圾焚烧底渣用作水泥混凝土掺和料研究

生活垃圾焚烧底渣有一定火山灰活性,有可能作为水泥混凝土掺和料使用.研究了底渣-硅酸盐水泥体系的物化性能、强度和水化,及该体系对减水剂的吸附规律.结果显示,随底渣掺量增加,该体系标准稠度需水量和凝结时间有所增加,水泥水化变慢,胶砂强度降低,对减水剂的吸附量显著增加.研究显示,底渣可用作水泥混凝土掺和料,但需注意底渣的掺入有可能降低减水剂效率.     

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-