公交客车气制动继动阀性能测试系统研究

通过对继动阀在汽车气制动系统的作用,以及其在气制动系统中工作原理的分析,提出了继动阀的性能测试方法,设计了继动阀的测试系统.该系统主要包括工控机、数据采集系统、气动系统、排气系统、传感器、控制电路.当气压调节范围为0.05～1.5MPa,气压测量范围为0～ 1.2MPa时,继动阀性能测试结果表明,气压测量精度可以达到0.25％,系统测试精度高,满足设计要求.     

铸造模具的模块结构图及总体框架

讨论了参数化设计系统的基本原理,构建了铸造模具工艺装备系统的总体框架和模样系统、浇注系统、冒口系统、工装系统各个分系统的结构组成。     

系统可靠性技术在铸造生产中的应用 第五讲 系统可靠性预测

铸造系统或铸造设备是由零部件组成的,因此,零部件的可靠性是系统可靠性的基础。人们在实践中认识到,选用最可靠的零部件不一定能组装出最可靠的系统。相反,只要设计、组装、使用得当,选用低可靠性的零部件也可能组成可靠性较高且成本低的系统。这是因为系统的可靠性不仅与零部件的可靠性有关,还取决于构成系统的零部件组合方式。本讲讨论已知零部件可靠度求系统可靠度。机械系统,按其组合方式的不同,可以划分为:串联系统、并联系统、由串联和并联混合组成的串并联系统、复杂系统等。     

铸造工艺装备除尘系统的设计改进

基于节能降耗、清洁生产和资源可循环的原则,对铸造过程相关装备的除尘系统进行了设计改进,包括电炉除尘系统、水力清砂及废水处理系统、铸件落砂及除尘系统、抛丸机除尘系统、铸件清理线和砂再生及除尘系统.生产实际运行结果表明,采用改进后的工艺系统,改善了工人的操作环境,能满足国家相关环保标准的要求.     

液压阀门检测装置

本实用新型公开了一种液压阀门检测装置,包括机床、控制柜、液压原理系统、电气原理系统、管路原理系统、左右工作盘、泵、夹紧装置及连杆机构,所述控制柜安装在机床的右侧,液压原理系统、电气原理系统、管路原理系统在控制柜内,左右工作盘上活动夹爪的径向移动采用连杆机构,所述右侧工作盘设有翻转90。的机构。本实用新型具有测试结果准确、     

常用快速成型系统及其选择原则

目前已经商品化的RP系统众多 ,且同一种系统又有不同的制造商 ,系统的性能价格比各不相同。因此 ,如何选择合适的RP系统 ,是用户比较头疼的一个问题。本文简要介绍了LOM、SLS、SLA和FDM四种常用RP系统的工作原理、优缺点和主要的RP系统型号及其制造商 ,从RP系统的用途、制件精度、成型材料、成型空间、成型效率、激光功率、成本和技术服务等方面出发 ,提出了一些选用常用RP系统的原则 ,并举例予以说明。     

郑州三磨研究所党组织和个人一受到科技局党委表彰

近日,郑州市科技局党委做出决定,表彰2009年度科技局系统党建工作先进集体和先进个人。郑州磨料磨具磨削研究所党委获郑州市科技局系统先进党委称号、纪委获郑州市科技局系统纪检监察工作先进集体称号、第四党支部被命名为市科技局系统先进党支部。该所共产党员李克华同志被命名为市科技局系统优秀共产党员标兵,共产党员陈恩厚、陈怀亮同志被命名为市科技局系统优秀共产党员,肖锋同志被命名为市科技局系统优秀党支部书记,张歌旗同志被命名为市科技局系统优秀宣传工作者,江瑾同志被命名为市科技局系统优秀监察工作者,李铭铭同志被命名为市科技局系统优秀老干部工作者。     

钢液真空精炼用全干式真空泵系统的设计及应用

全干式真空泵系统具有启动快、性能稳定、能耗低、环保、寿命长的优势,并在钢液真空精炼上得到了的具体的应用。介绍了全干式真空泵系统和常规真空系统的优缺点,介绍了100 t VD全干式真空泵系统内烟气预处理系统以及干式泵系统的设计方法,讨论了全干式真空泵系统的设计方法及应用中存在的问题和解决措施,为全干式真空泵系统在行业内的设计、选型、运行和投资提供了一定参考。     

液压助力转向器可靠性试验系统的设计

介绍了一种综合利用机、电、液技术的液压转向器可靠性试验系统,该系统能进行转向器各项可靠性试验.阐述了液压转向器试验系统的国内研究现状,介绍了系统的设计目标,分析了系统的总体设计、电气设计、机械设计、液压设计、软件实现、结果的处理等方面的内容.使用结果表明:该系统具有稳定性较高,操作简单、测量精度高、响应速度快、实用性较高等特点.     

可重构制造系统及其关键技术

文章首先对制造系统的发展历程进行了叙述,分析了专用制造系统、柔性制造系统和可重构制造系统产生的历史背景以及专用制造系统、柔性制造系统在目前的环境中存在的弊端,可重构制造系统产生的必然性,接着阐明了可重构制造系统的可变性、模块化、集成性、可诊断性等特点,从设备层论述了机床功能模块合理划分、模块之间机械界面的标准化、机床可移动性研究和基于软构件的设备层控制系统等关键技术,从系统层论述了可重构制造系统的建模、制造系统可重构布局研究、车间层控制结构的研究、为缩短斜升时间的故障诊断和过程监控等关键技术,最后对可重构制造系统的发展进行了预测.     

Effects of Post-weld Heat Treatment on Microstructure,Mechanical Properties and the Role of Weld Reinforcement in 2219 Aluminum Alloy TIG-Welded Joints

In as-welded state, each region of 2219 aluminum alloy TIG-welded joint shows diff erent microstructure and microhardness due to the diff erent welding heat cycles and the resulting evolution of second phases. After the post-weld heat treatment, both the amount and the size of the eutectic structure or θ phases decreased. Correspondingly, both the Cu content in α-Al matrix and the microhardness increased to a similar level in each region of the joint, and the tensile strength of the entire joint was greatly improved. Post-weld heat treatment played the role of solid solution strengthening and aging strengthening. After the post-weld heat treatment, the weld performance became similar to other regions, but weld reinforcements lost their reinforcing eff ect on the weld and their existence was more of an adverse eff ect. The joint without weld reinforcements after the post-weld heat treatment had the optimal tensile properties, and the specimens randomly crack in the weld zone.     

新型的治疗阿尔茨海默氏症药物(1-二甲基磷酰基-2,2,2-三氯)-乙基-1-醇烟酸醋对体外神经细胞的作用

目的: 观察本实验室合成的一种治疗阿尔茨海默氏症(AD)的药物(1-二甲基磷酰基-2, 2, 2 -三氯)-乙基^-1-醇烟酸醋(NMF),对体外培养的皮层神经细胞活性的影响以及对海人藻酸(KA)所致的神经损伤的保护作用。方法: 采用体外培养皮层神经元的方法,解剖分离 15 d胚胎小鼠皮层神经细胞, 接种于 96孔板,48 h 后加药并培养 72 h,以 MIT 法 观察 NMF 对小鼠皮层神经细胞活性的影响;同时将接种于 24 孔板的细胞预先给予 NMF,d 3 时加或不加KA处理后,以台盼蓝染色鉴别并计数死、活细胞,可得出细胞的存活率。结果: NMF 明显促进胎鼠皮层神经元活性,其中 NMF1、0. 1、10nmol·L^-1促进神经元活性增殖率分别高达 34.7%、37.4%、36. 7%, NMF 明显促进正常胎鼠皮层神经元存活卒,与对照组比较,10nmol·L^-1 NMF 对皮层神经元的存活率分别提高 39.3%、73.5%。 NMF能显著 对抗 KA 所致的神经元损伤,与 KA 损伤组相比, NMF0.1、10、10nmol·L^-1对损伤皮层神经元的保护率分别为 77.30%、80.10%、84.15%。结论: NMF 明 显促进胎鼠皮层神经元的洁性、提高正常皮层神经元,的存活卒,并能有效地保护KA所致的神经元损伤,提示 NMF 是一种很有潜力的治疗 AD 的药物。     

The First Phase of the SRIF Industrialized Base in ＂West Area＂ Has Been Put into Operation

After nearly two years＇ tense construction, the first phase of industrialized base of Shenyang Research Institute of Foundry （SRIF）, located at the Tiexi Casting and Forging Industrial Park in the west of Tiexi District, has now been completed and formally put into operation.     

THERMODYNAMICS STUDY ON THE DECOMPOSITION OF CHROMITE WITH KOH

Institute of Process Engineering, Chinese Academy of Sciences, China, has proposed a method for oxidative leaching of chromite with potassium hydroxide. Understanding the mechanism of chromite decomposition, especially in the potassium hydroxide fusion, is important for the optimization of the operating parameters of the oxidative leaching process. A traditional thermodynamic method is proposed and the thermal decomposition and the reaction decomposition during the oxidative leaching of chromite with KOH and oxygen is discussed, which suggests that chromite is mainly destroyed by reactions with KOH and oxygen. Meanwhile, equilibrium of the main reactions of the above process was calculated at different temperatures and oxygen partial pressures. The stable zones of productions, namely, K2CrO4 and Fe2O3, increase with the decrease of temperature, which indicates that higher temperature is not beneficial to thermodynamic reactions. In addition, a comparison of the general alkali methods is carried out, and it is concluded that the KOH leaching process is thermodynamically superior to the conventional chromate production process.     

INFLUENCE OF HEAT TREATMENT ON DAMPING BEHAVIOUR OF THE MAGNESIUM WROUGHT ALLOY AZ61

The effect of isochronal heat treatments for 1h on variation of damping, hardness and microstructural change of the magnesium wrought alloy AZ61 was investigated. Damping and hardness behaviour could be attributed to the evolution of precipitation process. The influence of precipitation on damping behaviour was explained in the framework of the dislocation string model of Granato and Lücke.     

Theoretical Analysis for the Motion and Temperature of Melt Droplets in Spray Degassing Process

The motion of melt droplets in spray degassing process was analyzed theoretically. The height of the treatment tank in spray degassing process could be determined by the results of theoretical calculation of motion of melt droplets. To know whether the melt droplets would solidify during spraying process, the balance temperature of melt droplets was also theoretically analyzed. Then proof experiments for theoretical results about temperature of melt droplets were carried. In comparison, the experimental results were nearly similar to the calculation results.     

Growth Kinetics of Single Inclusion Particle in Molten Melts

On the basis of the single-particle framework, a new theory on inclusion growth in metallurgical melts is developed to study the kinetics of inclusion growth on account of reaction and collision. The studies show that the early growth of inclusion depends on reaction growth and Brawnian motion collision, and where the former is decisive, the late growth depends on turbulence collision and Stokes＇ collision, and where the former is dominant; collision growth is very quick during the smelting process, lessened in the refining process, but nearly negligible in the continuous casting process.     

Three-Dimensional Growth of Coherent Ferrite in Austenite: A Molecular Dynamics Study

Coherent second phase often exhibits anisotropic morphology with specifi c orientations with respect to both the second and the matrix phases. As a key feature of microstructure, the morphology of the coherent particles is essential for understanding the second-phase strengthening eff ect in various industrial alloys. This letter reports anisotropic growth of coherent ferrite from austenite matrix in pure iron based on molecular dynamics simulation. We found that the ferrite grain tends to grow into an elongated plate-like shape, independent of its initial confi guration. The fi nal shape of the ferrite is closely related to the misfi t between the two phases, with the longest direction and the broad facet of the plate being, respectively, consistent with the best matching direction and the best matching plane calculated via the Burgers vector content(BVC) method. The strain energy calculation in the framework of Eshelby's inclusion theory verifi es that the simulated orientation of the coherent ferrite is energetically favorable. It is anticipated that the BVC method will be applicable in analysis of anisotropic growth and morphology of coherent second phase in other phase transformation systems.     

An Easy Way to Quantify the Adhesion Energy of Nanostructured Cu/X(X=Cr,Ta,Mo,Nb,Zr) Multilayer Films Adherent to Polyimide Substrates

An approach based on film buckling under simple uniaxial tensile testing was utilized in this paper to quantitatively estimate the interfacial energy of the nanostructured multilayer films(NMFs) adherent to flexible substrates. The interfacial energies of polyimide-supported NMFs are determined to be *5.0 J/m2 for Cu/Cr, *4.1 J/m2 for Cu/Ta,*2.8 J/m2 for Cu/Mo, *1.1 J/m2 for Cu/Nb, and *1.2 J/m2 for Cu/Zr NMFs. Furthermore, a linear relationship between the adhesion energy and the interfacial shear strength is clearly demonstrated for the Cu-based NMFs, which is highly indicative of the applicability and reliability of the modified models.     

High-Speed Friction Stir Welding of SiC_p/Al–Mg–Si–Cu Composite

A 17 vol% SiCp/Al–Mg–Si–Cu composite plate with a thickness of 3 mm was successfully friction stir welded(FSWed) at a very high welding speed of 2000 mm/min for the first time. Microstructural observation indicated that the coarsening of the precipitates was greatly inhibited in the heat-affected zone of the FSW joint at high welding speed, due to the significantly reduced peak temperature and duration at high temperature. Therefore, prominent enhancement of the hardness was achieved at the lowest hardness zone of the FSW joint at this high welding speed, which was similar to that of the nugget zone. Furthermore, the ultimate tensile strength of the joint was as high as 369 MPa, which was much higher than that obtained at low welding speed of 100 mm/min(298 MPa). This study provides an effective method to weld aluminum matrix composite with superior quality and high welding efficiency.