超声振动辅助钻削钛合金的机理和工艺研究

随着时代的发展,经济的增长,社会的进步,我国的综合国力逐渐提高,科学技术不断的改良、创新、进步,而这些改变随之而来的是我国的工业发展越来越迅速,以往的封建的旧的思想以及旧的技术、产品已近满足不了这个时代的需求,人们的生活水平不断提高,对于新兴的产品以及技术的需求越来越高,超声振动辅助钻削钛合金技术的发展就是其中之一。     

微型汽车发动机尾气污染排放的模拟分析

随着科技的进步,人们的出行方式产生了巨大的变化,汽车的普及在给人们的出行提供前所未有的便捷的同时,其产生的污染也是十分严重的,汽车发动机所造成的污染问题不仅减低了环境质量,同时对人们的身体健康也造成了威胁。基于此,本文针对机动车中的微型汽车进行相应的发动机尾气污染排放的研究,指出污染物的危害,并针对性的提出相应的治理措施。     

电动汽车电池的发展现状与趋势

在经济日益发展的今天,环境问题越来越严重,其中最主要的问题是气候的变化和空气的污染。而空气的污染,最重要的原因是煤炭等资源的燃烧。由于对资源的过度开发使得能源日益的紧张。在资源紧张的大背景下,科学家们正在考虑开发新的清洁能源,比如水能,风能和太阳能等。在这个形势下,电动汽车利用自身的清洁环保的优势,从而得到很多人的推广和运用。而电动汽车的核心是电池,电力工业与汽车工业,之间的核心纽带是电动汽车的电池部分,电动汽车的电池也是这两者之间所联系的重要桥梁和纽带。用清洁的电能来替代传统的汽车供应的石油化工,能源是现在社会的大发展趋势下所必然的过程。本文将针对于电动汽车电池的发展现状与趋势进行科学合理的分析,并对电动汽车电池的未来发展状况给予比较科学的推测。     

对航空工业机械加工的技术改造分析

制造业是国家发展的重要基础,其决定着工业生产发展的水平,而制造业的加工技术是否足够先进,对制造业的发展以及整个国家经济的发展有直接的影响。航空工业作为高精尖行业,对设备的运行性能有着非常高的要求,为了能够达到机械设备相应的精度,对机械加工提出了较为严格的要求,而为了满足相关航空产品使用的要求,机械产品必须具备非常高的加工精度,但目前我国的部分航空产品的加工可能还达不到实际的要求,从而对航空工业的发展产生较大影响。针对这种情况,本文对航空工业机械加工技术目前的现状以及存在的问题进行了相应的分析,在此基础上有针对性的明确了具体的技术改进方案,对航空工业机械加工的进一步发展有较大的促进作用。     

FRA在变压器绕组变形故障诊断中的应用

变压器的电磁分析在科学研究和工程应用中一直是一种研究变压器故障的重要方法。目前基于FRA的变压器绕组的建模多数都是单一的电路模型,忽略的磁场方面的重要作用。因此利用大型多物理场耦合软件建立变压器绕组的二维有限元模型,用场路耦合的方法实现了变压器的漏磁场仿真。模拟了绕组的变形故障,采用FRA的方法分析研究绕组径向的变形尺寸以及发生变形的位置对变压器绕组的传递函数的影响,对变压器绕组故障的研究提供一定的理论指导。     

消费者个性化的虚拟商店设计构建

传统的实物商店只能给出单调的一种店面布局,而在当今的买方市场中,这种单调的一种店面布局难以迎合所有消费者的口味,因此使得商家失去了许多潜在的营销机会.本文拟改进关联规则挖掘理论中的核心算法-著名的Aprior算法,并采用该改进的Aprior算法对商业网站在网络营销中获得的海量的客户访问日志文件分析,构建起互联网上的符合每个消费者的购买偏好的个性化的虚拟商店.这样,就可以实现网络营销中的商家针对单个消费者的一对一的个性化营销,达到商家和消费者双赢的博弈均衡状态(即实现Pareto最优).个性化的虚拟商店的设计代表着国际商业巨头竞相追逐的网上营销的核心竞争技术和难点技术,因此本文的研究仅仅只是一种尝试和创新.     

PLC技术在机械电气控制装置中的应用

当前PLC技术在现代化的机械电气控制装置的操作和使用过程之中有着相当重要且广泛的使用．同时PLC技术的发展对于提升我国当前的机械电气装置的操作技术水准也有着重大的意义。故应当加强对PLC技术的重视和深刻的研究，同时加强对技术核心层面的分析，以更好的实现工作项目的向前发展。文章将针对这一方面的内容展开论述，详细的分析了PLC技术在实践之中的操作应用基本状况，同时对技术操作的难点以及技术应用过程之中应当重点掌控的问题等进行了系统性的分析，旨在以此为基础不断的实现机械控制技术的向前稳定发展。     

浅谈煤矿井下人员定位系统技术的研究

在当前人们普遍关注煤矿井下人员的工作状况的情况下,为了最大的保障下井人员的各方面的安全,针对于井下人员的定位系统研究也取得很大的进展。本文主要介绍一种基于RFID的技术的前提下的井下人员的定位系统,这个系统采用无线技术进行数据收集,有线的方式来传递数据,在每名人员的身上配备一台身份码的发送器,继而通过无线信号来把人员的编号可以发送出去,在井下的规定距离地方设置监测站点,站点再把信号传回地面,这一整套的过程进行详细的讲解。     

起重机械安装监检中的常见问题探析

随着社会的发展，经济的进步，工作生产也取得了大发展。在时代日新月异的发展过程中，起重机械的出现，解决的过去所不能解决的工业上的难题，实现了在过去无法实现的较大物品的移动或搬运的工作，切实的提高了工业生产中的工作效率，减少了人力的投入。起重机械在工业生产中发挥着越来越大的作用，对起重机的安全问题也越来越重视，但由于起重机械的构造比较复杂，因此必须注意起重机的安装检测，本文就是要探析起重机安装检测中常见的问题。     

软件功能与企业业务充分结合——长液ERP项目经验谈

ERP不是技术的问题,而是解决企业的管理问题。而管理的问题与企业的高层领导、各部门的中层领导息息相关。因此,合理的选型小组应该是由公司的高层领导挂帅(副总以上),各主要业务部门领导参加,IT部门牵头。高层领导把握的是该管理软件的管理思想和自身企业的匹配程度、该合作伙伴的稳定性等;各业务部门领导把握的是该软件和自身部门需求的适应度;IT部门把握的是该软件的技术和总体的架构合理性,以及未来发展的可扩展性、前瞻性等。     

Prediction of forced convective boiling heat transfer coefficient of pure refrigerants and binary refrigerant mixtures inside a horizontal tube

Forced convective boiling heat transfer coefficients were predicted for an annular flow inside a horizontal tube for pure refrigerants and nonazeotropic binary refrigerant mixtures. The heat transfer coefficients were calculated based on the turbulent temperature profile in liquid film and vapor core considering the composition difference in vapor and liquid phases, and the nonlinearity in mixing rules for the calculation of mixture properties. The heat transfer coefficients of pure refrigerants were estimated within a standard deviation of 14% compared with available experimental data. For nonazeotropic binary refrigerant mixtures, prediction of the heat transfer coefficients was made with a standard deviation of 18%. The heat transfer coefficients of refrigerant mixtures were lower than linearly interpolated values calculated from the heat transfer coefficients of pure refrigerants. This degradation was represented by several factors such as the difference between the liquid and the overall compositions, the conductivity ratio and the viscosity ratio of both components in refrigerant mixtures. The temperature change due to the concentration gradient was a major factor for the heat transfer degradation and the mass flux itself at the interface had a minor effect.     

Lubricity characteristics of ethyl hexyl esters of mono‐, Di‐, and triethenoic acids

Ethyl hexyl esters of oleic, linoleic, and linolenic acids were synthesised and thermally polymerised to obtain products with viscosities in the range of hydrocarbon lubricants at 100°C (11–22 cSt). Molecular weight, elemental analysis, IR, ¹³C NMR, and intrinsic viscosity data showed that most of these derivatives are mixtures of monomers, dimers, and trimers and have linear and cyclic products with predominantly trans characteristics. The lubricity characteristics were determined on a friction and wear tester under conditions of thick‐film lubrication. A comparison was made with hydrocracked hydrocarbon lubricants of comparable viscosities at 100°C and comparable viscosity indices. It is inferred that all the esters maintained relatively thicker surface films and much lower friction coefficients than the hydrocarbon oils. The wear‐scar data show that the antiwear characteristics of polymerised ethyl hexyl oleate and linoleate are only slightly inferior to those of the hydrocarbon oils, but at higher temperatures their antiwear characteristics rapidly deteriorate while the friction coefficients markedly increase and become comparable to those of hydrocarbon oils. These studies are being undertaken with a view to selecting and modifying vegetable oils containing mixtures of fatty acids for obtaining esters of outstanding friction, wear, and film‐forming characteristics.     

含气油液有效体积弹性模量理论模型研究

为准确预测含气油液在空气分离压下有效体积弹性模量的值,基于油液体积弹性模量定义和质量守恒定律,依据含气油液中气相成分随压力的变化过程,推导出含气油液有效体积弹性模量理论模型。数值计算结果表明：含气油液有效体积弹性模量理论模型B-p曲线与现有理论模型及实验数据拟合曲线基本吻合,验证了理论模型的正确性,特别是在低于大气压的极低压区,有效体积弹性模量预测值更加接近实际情况。分析了初始含气量、压力、升压时间对有效体积弹性模量的影响,结果表明：在低于空气分离压范围内,初始含气量增大,有效体积弹性模量减小;在一定范围内,升压时间增大,有效体积弹性模量小幅度增大。     

Anomalous Dependence of Wear Properties on the Mixture Composition of Hydrocarbon Oils with Polyorganosiloxanes

In the course of studying the dependence of wear properties on the composition of a mixture of hydrocarbon oils with polyorganosiloxanes, it has been revealed that adding 10 wt % hydrocarbon oils to polyorganosiloxane leads to significant growth in the diameter of the wear pot. A further increase in the content of hydrocarbon oils in the mixture at a concentration of ~30 wt % induces a sharp decrease in the wear parameter and it has a value lower than that for a clean oil. An analogous, but less expressed dependence for antiscuff properties has been observed. The values of density and viscosity of the mixtures in the same limits was detected. Based on element analysis, IR spectroscopy, and roentgen fluorescent analysis, the nature of the found effect has been proposed.     

Horizontally installed cone differential pressure meter wet gas flow performance

Differential pressure (DP) meters which utilise a cone as the system’s primary element are increasingly being used to measure wet natural gas flows (i.e. mixtures of natural gas, light hydrocarbon liquids and water). It is therefore important to understand this meter’s response to wet natural gas flows. Research into the wet gas response of the horizontally installed cone DP meter is discussed in this paper. Consideration is given to the significant influence of the liquid properties on wet gas flow patterns and the corresponding influence of the flow pattern on the cone DP meter’s liquid phase induced gas flow rate prediction error. A wet natural gas flow correlation for 4 in. 0.75 beta ratio cone DP meters with natural gas, hydrocarbon liquid and water flow has been developed from multiple data sets from three different wet gas flow test facilities. This corrects the liquid induced gas flow rate prediction error of a wet gas flow up to a Lockhart–Martinelli parameter of 0.3, for a known liquid flow rate of any hydrocarbon liquid/water ratio, to ±4% at a 95% confidence level.     

Effects of Aryl Phosphate Ester Lubricant Additives on Crack Growth in Soda-Lime Glass

The growth of cone cracks in soda-lime glass during static loading with a spherical indenter shows that crack growth is accelerated at low energy release rates (low crack velocity) by tricresyl phosphate. Other aryl phosphate ester lubricant additive mixtures that contain predominantly larger molecules, as well as a synthetic hydrocarbon oil formulated with one of the mixtures, do not show enhancement of crack growth. Although reactivity in a test with static load can predict reactivity in a cyclically loaded test, lack of reactivity in a static test may not predict lack of reactivity in a cyclic test. Comparative tests with neat hydrocarbon oil and formulated oil under the same cyclically loaded conditions are needed to definitively determine whether the additives that are unreactive in these static tests influence crack growth in a bearing.     

The Determination of Vapor Pressures of Low Viscosity Lubricants from Distillation Data

The vapor pressure of low viscosity aliphatic hydrocarbon lubricants is shown to be determined with good accuracy from data obtained from a modification of the ASTM Distillation Test D86-67. This test gives the initial boiling point of a lubricant from which the vapor pressure at any other temperature can be calculated by use of an empirical equation relating the boiling point to the vapor pressure.

Two other equations were derived, one relating the viscosity of an aliphatic hydrocarbon lubricant to the vapor pressure at any temperature, and the other extending the use of this distillation method to calculation of the vapor pressures of other types of lubricants as, for example, esters, alcohols, and acids.

The data presented indicate that this method is superior to the isoteniscope method in accuracy and ease of operation.     

Numerical Calculation of Minimum Ignition Energy for Hydrogen and Methane Fuels

Minimum ignition energies of hydrogen/air and methane/air mixtures have been investigated numerically by solving unsteady one-dimensional conservation equations with detailed chemical kinetic mechanisms. Initial kernel size needed for numerical calculation is a sensitive function of initial pressure of a mixture and should be estimated properly to obtain quantitative agreement with experimental results. A simple macroscopic model to determine minimum ignition energy has been proposed, where the initial kernel size is correlated with the quenching distance of a mixture and evaluated from the quenching distance determined from experiment. The simulation predicts minimum ignition energies of two sample mixtures successfully which are in a good agreement with the experimental data for the ranges of pressure and equivalence ratio.     

An experimental setup for simulation of two-phase hydrocarbon mixture flow in porous stratums

A procedure for simulating the two-phase flow of three-component hydrocarbon gas mixtures (for example, of the methane-propane-butane mixture gas condensate) in a porous stratum with the use of strain-gauge pressure sensors is proposed. Results are presented of experimental studies of two-phase hydrocarbon methane-propane-butane mixture filtration through a porous medium on the PLAST setup of the Joint Institute for High Temperatures under conditions close to reality. It is shown that the coordinate of the gas condensate plug formation region in the experimental section of a pipe can be determined with an accuracy up to 10% of its length.     

Evaluation of mechanical properties of nano-clay modified asphalt mixtures

This study aimed to investigate the performance of nano-clay modified asphalt mixtures. This study aimed to investigate the performance of nano-clay modified asphalt mixtures. Three different nano-clay materials were selected and each modifier was used with three different concentrations (2%-3.5%-5%) as substituted for filler.Modified Lottman including hot water conditioning (conditioning 1) and cold water conditioning (conditioning 2) systems were used. Models of water damage were used on half of the identical compacted samples. Cracking, stripping and rutting evaluations were realized with AASHTO T 283 Modified Lottman Test and repeated creep tests (RCT) with Nottingham asphalt tester (NAT). Indirect tensile strength (ITS) tests were realized with control and two types of conditioning systems but RCT were applied with control and Lottman water damage procedure. Nano-clay materials increased rutting resistance of samples with Lottman water damage conditioning method. 2%, 3.5% and 5% nano-clay modified mixtures were found as more rutting resistance than the conventional mixtures according to the AASHTO T283 conditioning. Indirect tensile strength tests were realized with Lottman moisture damage conditioning model. Higher tensile strength values were obtained with 2% and 3% nano-clay modified asphalt mixtures denotes that higher internal friction. Stripping damage of the modified mixtures was interrogated with the ratios of tensile strength concept. In the ratios of tensile strength, 2% each of three nano-clay modified mixtures gives higher ratios. Stripping resistance of the 2% nano-clay mixtures was found as higher than the control conditioned samples based on Modified Lottman Test. It is thought that nano-clay modifiers can be successfully used in view of higher stripping, rutting and cracking resistance with low ratio as 2%. Stripping resistance increased with increasing nano-clay concentrations in view of conditioning 2. As a result of the mechanical test approaches 2% nano-clay content is thought as a suitable ratio in context with stripping, rutting and cracking optimization.