基于SolidWorks、HyperMesh与ANSYS的地埋升降式垃圾压缩箱结构分析与优化

采用CAD/CAE多软件集成方法分析了垃圾压缩箱结构.基于SolidWorks、HyperMesh与ANSYS,研究了三者的数据交互技术,并对箱体进行建模、网格划分及求解分析.针对分析结果,进行结构优化与对比,提高了结构力学性能.降低了重量与成本,为结构的改进设计提供了参考.     

谷物割捆一体农用车打捆系统设计

重点介绍了一种谷物割捆一体农用车打捆系统设计.主要针对小型农用作业车,设计了一种纵向打捆方式的打捆机.该打捆机利用链条传动特性,实现了绳套的储存功能,利用伸缩撞针实现取绳与放绳动作.并针对打捆系统设计了与之配套的喂料机构与输料机构.其中喂料机构利用旋转式叶轮将谷物压入打捆机实现喂料功能.输料机构利用可变间距式传送带实现临时储存与输送功能.通过ADAMS对打结器代替件打捆套筒进行了仿真,论证了可行性.     

双零件族随机环境下可重构制造系统的生产能力设计

基于概率论、排队论与更新理论的方法,建立了双零件族随机市场需求模型与可重构制造系统的排队控制模型.以可重构制造系统的生产能力与开机数量为参数,基于重构成本、制造系统折旧成本与仓储成本,构建了平稳条件下可重构制造系统长期运行时,单位时间内所取得的平均利润优化模型,并提出了优化方法与步骤.通过求解该模型,得到了可重构制造系统的最优生产能力与最佳开机数量.基于求得的最优生产能力与最佳开机数量,给出了可重构制造系统的订单接受率与切换周期等性能指标.最后,用案例验证了所提方法的可行性.     

特征提取与可制造性知识表达

针对零件的可制造性设计,研究制造信息的获取与表达方法.通过ACIS提取几何模型信息,建立制造特征库与采用基于规则的方法实现对制造特征的识别与重构.综合运用多种知识与推理机制,建立特征与制造资源、工艺知识的关联.解决了并行工程中的工艺性问题.开发的DFM系统验证了该方法的可行性.     

面向再制造的生产计划与调度研究综述

介绍了再制造的定义及作用.对再制造生产计划与调度的难点进行了分析.着重对再制造生产计划与调度领域的主要方法:最优化方法、启发式规则法、系统仿真法和遗传算法进行了阐述,并对生产计划与调度理论的发展现状进行了归纳.最后指出了可行的发展方向.     

基于能耗指标的拟人机器人步态优化与分析

通过引入基于平均功率、平均功率偏差、平均力矩损耗三个能耗指标对拟人机器人步态进行了优化与分析.基于拉格朗日方程推导了各个关节驱动力矩的计算公式,建立了拟人机器人步态优化的数学模型.使用Matlab作为优化与仿真工具,得到了一組拟人机器人步态参数最优解,分析了拟人机器人各个步态参数与拟人机器人能量消耗之间的关系.并给出了拟人机器人步态优化与分析的数值实例.     

混凝土泵车臂架可靠度分析

利用APDL语言建立了臂架的参数化模型,在置信水平95％的条件下应用PDS模块对混凝土泵车臂架进行了结构可靠度分析.执行循环1000次蒙特卡罗法计算,得到了臂架位移与应力的累积分布函数.进一步进行灵敏度求解,获得了影响臂架位移与应力的设计参数,得出了臂架长度与臂架宽度是两个主要的影响参数.使用响应面法分析,得到了两组关联参数影响臂架位移与应力变化的曲面.分析结果表明,两种方法求出的臂架位移值与应力值,其相对误差在5％以内.     

基于热敏电1阻的热式液体流量传感器

根据热消散效应原理,设计了一种基于热敏电阻的热式液体流量传感器.介绍了传感器设计模型及工作原理,通过流体力学软件FLUENT对传感器进行了液体温度场仿真分析,验证了传感器设计的可行性.通过实验与分析,求出了液体流量变化与所设计传感器对应的电压变化函数关系.进行了0～100 L/h流量范围液体流量测量,提出了传感器研究与改进的方法.     

基于装配指令的飞机装配作业工作结构分解快速生成算法

为快速生成飞机装配车间的详细作业计划,提高车间精细化控制能力,提出了一种基于装配指令的装配作业工作结构分解生成算法.该方法在车间工区与工位划分的基础上,建立了三级装配操作单元模型,细化了装配现场控制基础.通过装配指令与工作结构分解的分类信息映射规则,实现了装配工艺信息与车间作业计划任务信息的快速融合.利用操作单元模型与映射规则,建立了装配作业工作结构分解大纲与节点任务结构的自动生成算法.最后,使用自主开发的软件系统,对某型飞机外翼单元装配进行了实例分析,验证了方法的有效性.     

基于遗传算法和变邻域搜索的柔性作业车间同步调度方法

研究了现有的柔性作业车间问题求解算法中存在的计算等待时间与求解结果质量之间的矛盾.针对这一矛盾设计了一种名为同步调度的新型调度求解方法.同步调度实现了生产作业与调度计算同步进行,旨在同时满足零等待与精求解两大要求.基于遗传算法与变邻域搜索设计了两种同步调度算法.在静态与动态柔性作业车间问题上的仿真实验表明,同步调度算法快速而有效.     

Histochemical and ultrahistochemical localization of heavy metals in calf organs

Cadmium, zinc, selenium, and copper were administered, singly or in combination, orally or subcutaneously. Experiment I included 32 calves of both sexes; six received Cd (two groups), Zn, Cd, and Zn, and Cd and Se (two groups) and one group was a control. In Experiment II (21 bulls), three were given Cd, Cd, and Cu, and Cd and Zn, respectively, and one group was a control. For light microscopy, in Experiment I the highest amounts of silver granules were present in the samples of liver, small intestine, and vesicular gland of all the exposed groups; in Experiment II the most affected organs were liver, kidney, and small intestine. For electron microscopy, in Experiment I, after administration of Cd and Zn, the highest amounts of granules were seen in the cytoplasm of hepatocytes and cells of the proximal and distal renal tubules and the lowest amounts were found in glandular cells of the pancreas. Administration of Cd and Se resulted in the presence of large numbers of granules in the nuclei and nucleoli of spermatogonies. In Experiment II, ingestion of Cd and Zn in feed led to the appearance of highest amounts of granules in the nucleoli, nuclei, and cytoplasm of cells in testes, kidneys, and pancreas. Following Cd intake, the highest accumulation of granules was observed in the nucleoli of hepatocytes and cells of the proximal and distal renal tubules. Combined Cd and Cu produced the highest number of granules in cells of the proximal and distal renal tubules and in the nucleoli and nuclei of germinal epithelium.     

智能机床发展现状与技术体系框架

智能机床成为机床装备发展的趋势。在介绍国内外智能机床的研究现状的基础上,分析目前智能机床技术研究的三个问题,提出智能机床的狭义和广义定义;给出智能机床的包括人计机的协同性、整体与局部的协调性、智能的恰当性与无止性、自学习及其能力持续提高性、自治与集中的统一性、结构的开放性和可扩展性、制造和加工的绿色性、智能的贯穿性八个智能技术特征;阐述包括以人为中心的人计机动态交互功能、三个基本功能——执行智能功能、准备智能功能、维护智能功能的智能功能特征,以及功能之间的相互关系;建立八个理论与技术的智能机床技术理论框架,包括人计机一体化融合理论与技术、多源信息的感知理论与技术、智能决策理论与技术、智能执行理论与技术、智能维护理论与技术、智能机床综合能力评价理论与技术、智能机床标准化技术、智能机床支撑技术等,形成了智能机床的技术体系框架,同时指出上述内容将随着技术的进步和应用的深入不断充实和丰富。     

Review on microbial metabolomics of probiotics and pathogens: Methodologies and applications

In recent years, microbial metabolomics, a new field that has attracted wide attention, provides a map of metabolic pathways and clarifies the interaction mechanism between microorganisms and hosts. Many microorganisms are found in the human intestine, oral cavity, vagina, etc. Probiotics could maintain the good health of the host, while pathogens and an imbalance of bacterial flora lead to a series of diseases of the body and mind. Metabolomics is a science for qualitative and quantitative analysis of all metabolites in an organism or biological system, which could provide key information to understand the related metabolic pathways and associated changes. This approach analyzes the final products of cellular regulatory processes, the level of which can be regarded as the ultimate response of the biological system to genetic or environmental changes. Microbial metabolomics has been widely used in different research fields, such as microbial phenotypic classification, mutant screening, metabolic pathways, microbial metabolic engineering, fermentation engineering monitoring and optimization, microbial environmental pollution, and so on. However, there are only a few reviews on microbial metabolomics of probiotics and pathogens. This review summarizes the main methodologies, including sample preparation, identification of metabolites, data processing, and analysis. Recent applications in microbial metabolomics of probiotics and pathogens are also described. This paper first summarized the research progress and application of microbial metabolomics from two aspects: probiotics and pathogenic bacteria. Probiotics and pathogenic bacteria do not exist independently most of the time; hence, these were reviewed in the research field of coexistence of probiotics and pathogenic bacteria, which was subdivided into important microbial research fields closely related to human health, including the human gut, oral cavity, food, and nutrition-related microorganisms. Then, the main problems and trends associated with microbial metabolomics are discussed.     

Localization of sarcoglycan, neuronal nitric oxide synthase, beta-dystroglycan, and dystrophin molecules in normal skeletal myofiber: triple immunogold labeling electron microscopy.

In order to investigate the mode of existence of the sarcoglycan complex, neuronal nitric oxide synthase (nNOS), beta-dystroglycan, and dystrophin in the normal skeletal myofiber, we examined the ultrastructural localization and mutual spatial relationship of nNOS, beta-dystroglycan, dystrophin, and the individual components of the sarcoglycan complex by using triple immunogold labeling electron microscopy. Each molecule of alpha-, beta-, gamma- and delta-sarcoglycans is located intracellularly or extracellularly near the muscle plasma membrane mostly in accordance with the sarcoglycan antigenic sites against which the antibodies were generated. The association of different two and/or three sarcoglycan molecules out of alpha-, beta-, gamma- and delta-sarcoglycan molecules was frequently observed. Each molecule of nNOS, beta-dystroglycan, and dystrophin was ultrastructurally noted along the cell surface of normal skeletal myofibers. Moreover, the close relation of a sarcoglycan molecule with beta-dystroglycan and dystrophin, and the association of nNOS with dystrophin were also confirmed ultrastructurally. Thus, this study demonstrated that the constituting molecules of the sarcoglycan complex, nNOS, beta-dystroglycan, and dystrophin existed in the form of a cluster at the normal muscle plasma membrane. The association of nNOS with dystrophin and its associated glycoproteins may form a macromolecular signaling complex at the muscle plasma membrane.     

A simplified wet friction clutch test apparatus

A small, economic, test rig to evaluate friction materials and fluids for wet clutch applications has been designed, built and commissioned. In this paper, the construction, operation and performance of the machine are described, and results are presented, for two sets of typical tests. The system is capable of recording data, and torque test track, coefficients of friction, and oil temperature rise, are given.     

热喷涂宽温域耐磨自润滑涂层研究现状与展望

在航空、航天、冶金、电力、石化、矿采等领域,零件高温摩擦磨损特性是影响装备寿命的重要因素,在关重零部件表面设计制备宽温域耐磨自润滑涂层是装备零件强化改性和再制造修复的重要手段。首先阐述了宽温域耐磨自润滑涂层设计中过渡层、基础相、增强相的材料选择依据;其次针对单一固体润滑剂适用温度范围窄的问题,梳理了从低温润滑剂发生氧化反应原位生成高温润滑剂,低温润滑剂与高温润滑剂长时协同作用,添加抑制剂减缓润滑相的损耗退化等三种宽温域耐磨自润滑涂层材料设计方法;而后总结了宽温域耐磨自润滑涂层的制备工艺,分析了不同喷涂工艺的技术特点和涂层制备实例,介绍了宽温域耐磨自润滑涂层在军事装备和工业设备上的典型应用;最后在此基础上对宽温域耐磨自润滑涂层的未来发展方向进行了展望。     

铁碳合金相图的绘制

在分析铁碳合金相图特征的基础上,及说明相图中的特征点、线的含义的前提下,介绍了铁碳合金相图的画法,填写各区域的组织,从而完成整个铁碳合金相图的绘制.通过这种方式,能够较快地掌握铁碳合金相图的画法,理解相图中特征点、线及各区域组织的含义,对钢铁材料的选用和加工工艺的制订具有重要的理论和实践意义.     

GC/MS法同时分析液体制剂及口服液型保健品中31种防腐剂和抗氧化剂

为满足药品监管需要,建立了气相色谱-质谱（GC/MS）联用方法测定以水、醇等液体为基质的药品及保健品中的防腐剂和抗氧化剂。采用选择离子监测（SIM）技术,同时检测滴眼液、注射液、滴剂、涂剂、口服液型保健品中的三氯叔丁胺、苯酚、苯甲醇、山梨酸、苯甲酸、2-甲基异噻唑啉酮、脱氢乙酸、乙氧基喹啉、己基间苯二酚、对羟基苯甲酸酯等28种防腐剂及TBHQ、BHA、BHT等3种抗氧化剂。结果显示,31种物质在0.005~1 mg/L范围内具有较好的线性关系,线性相关系数为0.998 5~0.999 9;在0.02～0.30 mg/L加标范围内,回收率为73.6%～109.9%,相对标准偏差（RSDs）为1.2%～13.6%;检出限（LODs,S/N ≥3）为0.001～0.008 mg/L,定量下限（LOQs,S/N ≥10）为0.003～0.020 mg/L。应用该方法进行了多个批次的实际样品分析,结果表明,此方法灵敏、准确、稳定、可靠,且应用范围广泛。     

The new concepts of measurement error theory

In current measurement theory, there are various logical and philosophical troubles, and the evaluation concepts of measurement error are various and inconsistent among different schools. This paper throws away the shackle of the current measurement theories and concepts, and re-discusses basic measurement concepts. By proving a new measurement error theory that any error is a bias and follows random distribution, this paper points out the misunderstanding of traditional measurement theory, subverts the traditional error category theory, gives out a new interpretation of measurement uncertainty concept, proposes abolishing the concept system of precision, trueness, and accuracy, and thereby achieves the united measurement concept system across all the disciplines, including geodesy, geomatics, metrology, instrumentation, and so on.     

Diffraction methods in tribosystem diagnostics

In this paper, two structural analysis methods, X-ray diffraction and electron diffraction, are considered for their use in tribosystem diagnosis. It is shown that, for certain applied tribological problems, such as determination of friction conditions and type of wear regime, estimation of running-in period, selection of optimum wear-resistant materials, and of suitable conditions of friction and wear, these methods can be used in addition to more conventional tribotesting and tribodiagnostic methods. A study of the structure of certain friction pair materials and wear particles was conducted. X-ray investigations of the surface layers of the friction pair materials showed that structural characteristics, such as broadening and intensity of diffraction lines, can be used in the estimation of friction conditions. Examples of the choice of structurally wear-resistant engineering materials, and of suitable friction conditions, are given. The study of wear particles produced under different friction conditions shows that these particles vary not only in form and dimensions, but also in phase composition. This provides important additional information for friction and wear process diagnostics. The method involves electron diffraction analysis of isolated wear particles, which allows us to characterise the wear processes under friction conditions. It is shown that a definite phase composition, the fineness of wear particles, and the quantitative ratio of each of the wear product phases, can be characterised for different wear types. Some useful applications of these investigative methods for analysis of the wear nature of friction pairs are described.