LYWJ2-6型与 LYWJ2-12型液压式万能材料试验机的故障排除

排除方法油泵不出油(打开送油阀,工作台不能上升;关闭送油阀,回油管不出油)。1.油箱通往油泵的活栓未打开。2.油泵内有空气。1.打开活栓。使刻线与管路平行。2.排出油泵内的空气。油压脉动(送油阀的回油管出油脉动大,负荷示值检定时,标准测力计指针抖动)。1。2.3。4。5。油泵内有空气。油液粘度太小。送油阀调节针的间隙过大。油泵内有脏物。油泵球阀不密合,钢球、球座有划痕、毛刺,弹簧断裂、太软、卡死。1.排出油泵内的空气。2.更换适当粘度的油。3.减小调节针的间隙。4.清洗油泵。5.更换或修复相应零件。油压上升不平稳(由试验机指针可见…     

定格动画材质的探索和应用

本篇论文从两个部分来论述定格动画在材质方面的探索和应用问题。第一部分向大家简述关于定格动画的基本概论。通过1、定格动画的概念。2、定格动画基本原理和制作的流程。两个方面的简述，让大家对于定格动画有一个大体上的了解。第二部分主要是定格动画材质的应用与分析。从定格动画的常见的材质形式入手举例分析：1、泥偶——定格动画的分析。2、纸——定格动画的分析。3、木——定格动画的分析。4、沙——定格动画。5、金属——定格动画的分析。6、塑料——定格动画的分析。7、其它——材质定格动画的分析。     

《软件架构师》开刊词：面向服务的架构——敏捷系统探讨

设计商业软件时。我们应当提醒自己。我们的设计目标是交付支持业务的敏捷系统。而不是面向服务(SO)。更确切地说。SO是一种方法。通过它．我们可以实现业务和技术敏捷性。其本身并不是一个目标。特别是涉及Web服务时必须牢记这一点。实现几乎时刻伴随着Web服务的敏捷性。不仅是在系统部署过程中采用Web服务协议的结果。还是遵循良好设计原则的结果。本文将从良好的服务架构和设计原则对敏捷性和适应性的影响角度介绍相关的几个原则。     

新材料产业投资基金发起人招募启事

1．为什么设立产业投资基金？进入2004年，随着国家宏观控制的趋紧(4月份央行上调准备金率至8％。11月上调存贷款利率)。银行惜贷。企业资金链断裂。曾经一花独秀的房地产业。面临“崩盘”危机。大量优秀民企的重型化计划受挫。国内普遍存在的企业融资难问题更趋于严重。而另一方面。许多企业及民间拥有大量的资金却无法找到合适的投资途径(截至2004年10月。我国银行吸纳的居民、企业存款高达11万亿)。     

达到国内领先水平的“微网复合吸声板”科技成果通过鉴定

2001年10月28日由深圳市科学技术局主持,对深圳市国志汇富高分子材料股份有限公司研制的"微网复合吸声板"通过了技术鉴定。来自北京。成都。武汉。上海。深圳等地的专家学者一致认为,微网复合吸声板是一种新型的定型化吸声材料,它采用改性的合成高分子材料技术,制成阻燃。耐老化。吸声性能优良的微网材料,再将其经过表面无机胶凝材料处理,形成有机和无机两种材料复合的新型吸声板。它具有吸声系数高。耐水。阻燃性A级。成型加工和装饰性能优良,无二次污染。属无纤维。环保型新材料。可广泛应用于高速公路。轻轨。铁路。机场。高架道路等交…     

乳制品软包装的质量检测

随着经济的发展和人们生活质量的提高。消费者对乳制品的需求越来越多。众多的乳制品的生产厂家也不断推出新颖的包装来满足市场的不同需求。无菌包装、保鲜包装、耐蒸煮包装以及方盒式、屋顶式。软塑包装及瓶装等产品层出不穷。其中。乳制品的软包装以其独特的优势在整个乳品行业包装中所占的比例越来越大。而软包装产品的质量控制问题也愈来愈受到业界的关注。本文就是对乳品软包装产品质量检测技术的简要介绍。     

深冷文献消息(国外部分)

932010 管道(回)中冷凝过程的研究—一《X。。。、。。ediT。a。。ace,p.》1990932001 提高化工设备竞争能力的探求路径MI 15—18(i)ffXI。。n、·n。e扒·。a。11。ace,v·》1991 MI 932011 低温热交换器蛇形管流体力学特性1—3(俄)的研究932002 混合冷凝俗况下闭形管内热发幢的 ((。。、。。ediT。a。。。co。p.》1990研究 侦118—20(饼)‘X。。·。He扒。。。·》n肥 沁7 16-IS 932012 低羹工程芜部门国宗联合体及翼剑932003 压紧高压压缩机腹室的侵佳方法的立和发展前景途择《x。。H、。HH扒。T。;。HOCTP.》1990({。。114.11…     

浅谈建筑给排水施工图的审查

施工图会审是施工管理工作中施工准备阶段的一项重要技术工作。是建设的基本要求。目的是减少施工图的差错。确保工程质量和施工顺利进行。降低建设资金。审图是一项综合性很强的技术工作。需要考虑的事项千头万绪。以下是笔者在审图实践中总结的一些经验,仅供参考。     

与神对话巴别塔的纸上幻象

在《圣经旧约创世纪》中．洪水过后的苍茫大地上．世上所有人说着同一种语言。在靠近巴比伦城的地方，人类齐心协力。要“传人类之名．以免分散各地”。建造起通天的巨塔。上帝慌了散至各处。人类的通天梦想破灭。言，使人们四散至各处。人类的通天梦想破灭。     

聚焦PSC——PSC 2003回顾

由于SARS的影响，原定于2003年7月1日在上海国际展览中心举办的PSC2003。被迫延迟于10月22日开幕。但在四天的展览过程中。仍得到与会者的好评。本刊从媒体的视角，对本届展会进行简要的描述。以飨读者。     

Shrinkage compensation approach proposed for ABS material in FDM process

Dimensional accuracy of parts manufactured by Fused Deposition Modelling (FDM) greatly suffers from the shrinkage problems of the available polymer materials. This paper proposes a constructive idea for resolving the shrinkage issues and explains how shrinkage could be managed by interior geometry of the artifacts fabricated on desktop 3D printers. The main principle for preventing the deterioration on dimensional accuracy of the holes/slots is to utilize the auxiliary lines located from the hole’s perimeter to the outer boundaries of the artifact. Thus, the shrinkage of these auxiliary line segments simply helps to pull the original hole backward, acting against the predicted contraction. In this paper, the proposed approach will be examined using a finite element analysis tool to predict the shrinkage behavior of the fabricated samples along with necessary measurements taken on the Coordinate Measuring Machine. Additionally, an analytical framework for modeling the shrinkage behavior of ABS is to be elaborated. The coherence of the simulations and the measurements are to be analyzed regarding the effect of the geometry and material color on the shrinkage behavior. The discussion involves the improvement on the dimensional accuracy of 3D printed features.     

Dynamic simulation of a single-effect ammonia–water absorption chiller

A lumped-parameter dynamic simulation of a single-effect ammonia–water absorption chiller is performed. Modeling is based on the continuity of species constituting the ammonia–water mixture and the conservation of energy for each component of the absorption chiller. Ordinary differential equations governing the response of each component and the algebraic equations describing the constitutive relation are solved in parallel by numerical integration. The model has been applied to a commercially available 10.5 kW absorption chiller to study the transients of temperature, pressure, concentration, and void fraction of each component during the start-up operation. The time constant of the absorption chiller is also investigated. The parameters considered are the bulk concentration of the ammonia–water solution, the mass of the solution filled, and the volumes of key components of the absorption chiller. In addition, the reduction of the time constant by a stepwise turn-up and turn-down of the flue gas flow rate during the primary stage of start-up period is demonstrated.     

Capturing Nitrosamines in Environment by Zeolite

To meet the requirement of environment protection, the adsorption of volatile nitrosamines, which are carcinogenic compounds in tobacco smoke, by zeolite is investigated in this article, along with the temperature programmed surface reaction of nitrosamines on zeolite to assess the catalytic capability of the porous material on the decomposition of the carcinogens. The actual function of zeolite to reduce the level of nitrosamines in cigarette smoke is also studied. The influences of zeolite pore's structure and the surface acid-basic properties of the adsorbent on the adsorption are explored in terms of geometric matching content and adsorbent-adsorbate interaction. Moreover, the role played by the cation of zeolite in the adsorption of volatile nitrosamines is discussed and the possible attracting range of the sodium cation in basic zeolite to pull the nitrosamine molecule is tentatively calculated. Owing to the specific ability of capturing nitrosamines, zeolite is proven to be the most effective additive encased within a cigarette as the functional additive for lowering the nitrosamines content of smoke to protect the environment and public health. Other porous oxides such as amorphous silica and alumina are also utilized in these experiments, and their actual functions to trap nitrosamines as well as their potential application as the candidates for cigarette additives are discussed and prospected, too.     

Archaeometallurgical contributions to a better understanding of the past

Archaeometallurgical investigations, and in particular those employing metallographic techniques, have greatly increased our understanding of the past, primarily by improving our knowledge of the histories of technological developments. However, these studies have potential for contributing to our comprehension of many more aspects of life in the past. The series of case studies presented here illustrate the application of metallography not only in elucidating the history of technology but also in areas such as the dating of objects, the determination of the spread of technologies and the nature and implications of the contact of cultures with the ‘outside’ world.     

Modelling enthalpy and entropy of pure and mixed refrigerants with an innovative corresponding states method

In this work an original improvement of the Corresponding States technique is developed and a new model, based on a three parameters CS format, is proposed to predict the enthalpy and the entropy of the new generation halogenated alkanes fluids together with some alkanes. Limiting the analysis of the selected fluids to a specific thermodynamic property behaviour, an appropriate conformality approach can be deduced, which allows to set up a predictive model of high accuracy level on a wide range of the enthalpy and entropy surfaces. The fundamentals of the model are innovative scaling parameters deduced from the enthalpy of vaporization and from two dedicated equations, belonging to the selected family of fluids. This allows to set up innovative models following a CS format. Through the introduction of advanced mixing rules, the models can be simply extended to calculate the corresponding properties for mixtures. The proposed models allow also the calculation of VLE for systems of rather regular behaviour. The required inputs for a pure target fluid are an ideal gas isobaric heat capacity correlation, a single value of saturated liquid density and of vaporization enthalpy; if the last one is lacking, a single value of vapor pressure can be alternatively supplied. For non azeotropic mixtures the enthalpy and entropy models are predictive, whereas in case of azeotropy VLE calculations are possibly only applying regressed interaction coefficients. Due to the lack of accurate experimental enthalpy data and to the particular nature of the entropy function, the validation of the models is proposed against fundamental dedicated EoS available, both for pure and mixtures, for a significant number of the studied family of fluids. The predictive character of the proposed approach as well as the high performances reached, make these models particularly suitable for the new families of fluids regarding advanced technological applications.     

对广电数字化运动的几点看法——兼谈对信息时代的数字技术标准化意义的反思

从信息革命的角度对于当前这场广电数字化运动做定位分析。对当前数字电视领域中的一些有争议的问题提出了看法。如,公共平台与收费平台的关系,服务平台的统一,整体平移,外来标准和自主标准,数字标准的统一等。提出了对标准化意义的反思。指出,在信息时代,给社会和技术带来进步的往往是追求标准化的过程,而不是标准建立的事实本身。近几年来,许多人已经开始意识到工业时代标准化的“旧瓶”,已经很难装下信息时代数字技术的“新酒”。标准化的工作要有一种新思维来适应信息社会的变化和特点。     

Untersuchung von Schmelz‐ und Rekristallisationsprozessen sowie Riss‐, Oxid‐ und Porenbildung beim Schweißen

Investigation of melting and re‐crystallization processes and of crack, oxide and pore formation during welding In the paper some known investigation methods of the primary re‐crystallization and of the structure of the crystallization front are discussed. All these methods have disadvantages, in some cases they cause a limited validity or are expensive. The presented new method is based on the micrographic recording of the melting and solidifying metal surfaces. The method overcomes the above‐mentioned disadvantages. It is able to investigate in the welding seams not only the primary re‐crystallization processes but also the secondary ones including the formation of cracks and pores and the appearance of non‐metallic inclusions like oxides. The facilities of the method are demonstrated on some examples of use.     

Tragfähigkeitserhöhung bei Mauerwerk durch textilglasgitterverstärkte Mörtelfugen

Increase of the vertical load carrying capacity of masonry due to mortar bed joints with textile glass mesh reinforcement From a structural point of view, one of the most important material parameters in the construction sector is the vertical compressive strength of masonry, which consists of the compressive strength of the bricks as well as of the mortar bed. The interaction between the bricks and the mortar beds is the main reason for compression failures of masonry walls. A close analysis of the deformation behavior of the two components shows that different transverse strains in the contact surface between the bricks and the mortar are the main cause for compression failures. However, the load‐bearing capacity of masonry walls can be increased by using some reinforcement in the mortar beds which counteracts lateral expansion. The impact of textile glass mesh reinforcement on the load‐bearing capacity of masonry was analyzed in a test program on masonry columns with different numbers of textile glass mesh reinforced mortar beds. The results of the analyses show that the load‐bearing capacity of the columns rises with an increased ratio of reinforcement, regardless of the type of bricks used. From the ratio of the height of the reinforcement layers to the thickness of the wall it can be deduced that a higher degree of reinforcement has a positive effect on the load‐bearing capacity of the masonry. On this basis, an increase of the strength and load‐bearing capacity of masonry walls is formulated to be on the safe side.     

Numerical Analysis of Powder Properties in Low Power Plasma Torch

A mathematical model was presented to describe the particle trajectory, velocity and temperature properties in the low power plasma spraying torch (3.6 kW)in which powder particles were directly injected into the region between the cathode and anode. The results show that the characteristics of the particles by low power plasma spraying are similar to that by traditional APS( Atmosphere plasma spraying) in 40 kW. The velocities of the particles increase with the increase of inlet gas flow rate, current and percentage of nitrogen and hydrogen, while the temperature of the powder increase with the decrease of the gas flow rate and with the increase of current and percentage of nitrogen and hydrogen.     

Thermal conductivity of composites

A general expression for the effective thermal conductivity of inhomogeneous media in terms of the Fourier components of the spatial variation of the conductivity is applied to composites consisting of inclusions in a continuous matrix. It is reformulated in terms of the mean square fluctuations of the conductivity. Specific cases treated are spherical inclusions and long cylinders, both random and with preferred directions. The results hold provided the difference in thermal conductivities is small or provided the concentration of inclusions is not too large. The theory fails if the thermal conductivity of the matrix is much smaller than that of the inclusions. The same considerations also apply to electrical conductivity.