基于再生粗骨料裹浆厚度的含砂透水混凝土配合比设计方法

研究了不同水胶比下外加剂掺量对胶凝材料净浆流动度的影响,以及净浆流动度、中砂/净浆质量比双因素耦合作用下再生粗骨料裹覆砂浆厚度的变化规律;建立了胶凝材料净浆流动度与外加剂掺量,再生粗骨料裹覆砂浆厚度与净浆流动度、中砂/净浆质量比两个数学关联模型,并将两个数学关联模型应用到透水混凝土配合比设计中.结果表明,再生粗骨料裹覆砂浆厚度随砂浆流动度减小而增大,且骨料粒径愈大,其裹覆厚度愈大.采用再生骨料RCA-9.5配制含砂透水混凝土,其砂浆浆体稳定包裹再生粗骨料,无漏浆封底、露骨散架等问题;混凝土试件28 d抗压强度为14.1～17.1 MPa,28 d抗折强度为2.0～2.7 MPa,透水系数大于6 mm·s-1,抗冻性和耐磨性良好.     

地下商场的通风与空调设计

地下空间的内部环境优劣是影响人们身心健康的重要指标。作者通过地下商场通风空调施工实践,提出控制地下内部环境与节能所采取的措施,并谈几点粗浅看法,以供设计与运行管理参考。     

沥青搅拌站除尘设备工作原理及改进方法

本文详细论述沥青搅拌站袋式除尘器工作原理，分析了影响该除尘器工作效率的因素，提出了改进方法，对同类型除尘系统的沥青搅拌站的改进和维修具有一定指导意义。     

IMPROVEMENT OF ADHESION BETWEEN ION PLATED TiN COATING AND BASE METAL BY ADDING Y

The adhesion between the ion plated TiN coating and the base metal is improved byadding Y.The machenism of the effect of Y has been discussed as well.     

EFFECT OF CATHODIC PROTECTION ON FRACTURE BEHAVIOUR OF LOWALLOY STEELS IN SEAWATER

Fracture behaviour of low-alloy steels AIST4340,HY100,Welten60,AISIA537 and A131 inartificial seawater under static,cyclic loading and at cathodic protection potential has beeninvestigated by using the techniques of fracture mechanics, electrochemistry andelectronfractography.The results reveal that at hydrogen evolution potentials(cathodic pro-tection potential)the critical yield strength required for the occurrance of SCC decreasesfrom 985 at corrosion potential(E_c)to 872 MPa.The effect of cathodic protection on crackpropagation of corrosion fatigue(CF)is not simple,it is closely related to the yield strengthof steels and their SCC behaviour.For the steels with high yield strength,cathodic protectionpromotes(da/dN)_Ⅱ evidently,and reduces △K_(th) value.The(da/dN)-△K curves dis-play a plateau at the third stage of CF for steels with medium or low yield strength.It is men-tioned that the cathodic protection potential for oceaneering constructures should be control-led at top level of the protective range.It seems reasonable that the strength of steel foroceaneeing use might be increased by 200 or 300 MPa.     

PRECIPITATION OF TiC IN METASTABLE β-Ti ALLOY

In order to clarify that the IFP and the “Type 2”α phase are also arising from TiC,ametastable β-Ti alloy was selected for investigation in this work.The results showed that af-ter heating the alloy just below the α+β→β transus temperature and quenching,the TiC lay-er existed at the α/β interface.The morphology of TiC is similar to that of the IFP arisingfrom TiH_2 in the α-β two-phase alloys.The IFP TiC also provided an easy crack path orthe crack initiation sites.The fracture is also identical to that caused by IFP TiH_2.The arceddiffractions(characteristic of “Type 2”α)were found in the selected area diffraction pat-terns of some specimens which had been isothermally aged after solid solution treatment.Theparticles which bring on the arced diffractions may be TiC on the basis of structure and lat-tice parameter analysis,not the so called “Type 2”α phase.     

DETERMINATION OF PrCl_3-NaCl-LiCl PHASE DIAGRAM

PrCl_3-NaCl-LiCl phase diagram has been constructed from the phase diagrams of itssub-binary systems and of six quasi-binary systems measured by DTA technique.It is foundthat this ternary system is composed of five liquidus surfaces,seven second crystallizationlines,two peritectic points and one eutectie point.The temperatures and compositions ofinvariant points are as follows:P_1(416℃,30.3 mol% NaCl,44.2 mol% LiCl,25.5 mol%PrCl_3);P_2(409℃,25.0 mol% NaCl,50.0 mol% LiCl,25.0 mol% PrCl_3);E(404℃,20.0mol% NaCl,55.4 mol% LiCl,24.6 mol% PrCl_3).     

工程专业团队的管理

当今社会商业竞争激烈,讲求灵活和创新。现代企业因应时势需要,通常采取以团队为基础的工作小组的组织形式。工程专业机构主要由趋向自我领导和对自己工作表现严格要求的专业人员组成,因而指挥一控制模式不再是有效的管理工具。对于这些工程专业团队,我们需要发展新的思路对其进行管理,并加以激励。本文首先简述与职能部门结构相比,跨职能团队结构日趋流行的原因,进而阐述这类团队领导的典型职责,并根据最近的深入研究结果和笔者的经验,揭示一个有效的团队所具备的特征,因其对团队领导能否有效发挥职责至关重要。     

THE MECHANISM OF ACCEPTING, DONATING AND EXCHANGING ELECTRONS IN SUPERCONDUCTOR

１．ＴｃＶａｌｕｅｓｏｆＡｌｌｏｙａｎｄＭｅｔａｌｌｉｃＣｏｍｐｏｕｎｄｓＥｌｅｃｔｒｏｎｄｏｎａｔｉｎｇ,ａｃｃｅｐｔｉｎｇａｎｄｅｘｃｈａｎｇｉｎｇｈａｐｐｅｎｂｅｔｗｅｅｎａｔｏｍｓ,ｔｈｉｓｉｓｔｈｅｂａｓｉｃｍｏｄｅｌｏｆｈｏｗｍｅｔａｌｌｉｃｂｏｎｄｉｓｆｏｒｍｅｄ．Ｓｈａｒｅｄｅｌｅｃｔｒｏｎｐａｉｒｓｃａｎｍｏｖｅｆｒｏｍｏｎｅａｔｏｍｔｏｏｎｅｏｆｉｔｓａｄｊａｃｅｎｔａｔｏｍｓ．Ｗｈｅｎｔｈｅｐｏｔｅｎｔｉａｌｂａｒｒｉｅｒ（Ｐ）ｂｅｔｗｅｅｎｔｗｏａｄｊａｃｅｎｔａｔｏｍｓ…     

香豆胶与有机硼交联过程流变性研究——动态特性初步研究

香豆胶与有机硼交联压裂液是我国自行开发研制的性能优良的工程裂液之一,本文对其在一定条件下交联过程的动态特性进行了初步研究,考察了交联剂、温度等影响因素,对指导交联压裂液的研制,评价压裂液性能,优化压裂施工条件均具有实际意义,为推测压裂液的携砂性能和对携砂压裂液的开发研究提供理论指导。