示准化应用状态的构建与评价（下）

本文建立了多标准化状态的应用关系,并以多种标准化应用模型来评价载体标准化应用的结果,以此解决目前用标准化系数评价存在的单一性和简单性问题。本文构建了标准化应用状态的概念,给出了标准化应用状态的各种表征关系,建立了载体的标准化应用评价模型、载体标准化应用价值评价模型、载体标准化维度状态评价模型等数学模型,论述了标准化应用状态在产品、工程、企业、服务业等载体的应用。     

标准化应用状态的构建与评价（上）

本文建立了多标准化状态的应用关系,并以多种标准化应用模型来评价载体标准化应用的结果,以解决目前用标准化系数评价存在的单一性和简单性问题。本文构建了标准化应用状态的概念,给出了标准化应用状态的各种表征关系,建立了载体的标准化应用评价模型、载体标准化应用价值评价模型、载体标准化维度状态评价模型等数学模型,论述了标准化应用状态在产品、工程、企业、服务业等载体的应用。     

我国工程地质遥感技术应用特点与若干问题探讨

简要介绍了工程选线、选址勘测中遥感技术的应用概况;阐述了工程地质遥感技术应用的特点,认为工程地质遥感技术应用有别于其他领域;强调了我国工程地质遥感技术应用与其他国家不同,形成了我国自己的应用特点,这些特点是由我国国情决定的;探讨了工程地质遥感技术应用的若干问题,包括遥感图像判释,遥感图像处理、数据综合分析、施工阶段遥感技术应用等。     

用镁合金促进兵器装备轻量化

概述了兵器装备轻量化的意义、镁合金的性能特点,介绍了镁合金在兵器上应用的实例,指出了镁合金在兵器上应用存在的问题,分析了镁合金在兵器上应用的前景,对镁合金在兵器上的应用工作提出了若干建议.     

食品制造业RFID应用标准体系构建

为指导并规范食品制造领域应用RFID实现食品生产的质量安全管控,本文分析了国内外射频识别(RFID)标准及应用标准体系现状,研究了食品制造业特性及其应用RFID系统的需求,建立了食品制造业RFID应用标准体系构建模型,以模型为依托构建了RFID应用标准体系,并描述了该标准体系的架构、标识、信息采集、信息传输、信息应用等各标准单元的标准内容。     

测厚技术在炼化企业应用实例

介绍了超声测厚的原理及应用,并列举了在炼化企业的几个应用实例,阐述了测厚技术应用的重要性。     

工业工程技术在成都飞机工业公司的应用与探索

介绍了成都飞机工业公司工业工程的应用策略、目标及成果,对应用中存在的问题进行了简要分析,提出了今后的应用重点。     

在应用数学中引入数学建模思想的方法与分析

应用数学是纯粹数学的互补物,本文通过对应用数学特点的分析,阐述了在应用数学中引人数学建模思想的理论与方法,同时讨论了渗透数学建模思想的意义以及对应用数学改革的重要性。在应用数学中引人数学建模的思想可以极大提高学生的兴趣和教学的效果,拓展了应用数学的内涵。     

膜技术在次级代谢产物发酵和生物转化中的应用

概述了各种生物技术常用膜的理化特性及其发酵中的应用，列举了国内外应用实例，提出了膜技术应用中尚存在的问题。     

YC-1型电量无线遥测系统应用

文章介绍了电量无线遥测系统的技术原理及应用情况,分析了此系统应用后的经济效益,总结了应用后取得的效果。     

Study on latent heat of fusion of ice in aqueous solutions

In this study, latent heat of fusion of ice in aqueous solutions was measured to understand latent heat of fusion of ice slurries. Propylene glycol, ethylene glycol, ethanol, NaCl and NaNO₃ solutions were used as aqueous solutions. For measurements, pure ice was placed into solution, and temperature variations of the solution due to melting of ice were measured. Effective latent heat of fusion was calculated using an energy balance equation. Concentration of the solution varied due to ice melting, and dilution heat was considered. Therefore, latent heat of fusion of ice in aqueous solutions was predicted by considering the effects of dilution and freezing-point depression. We found that effective latent heat of fusion of ice decreased with increasing concentration of the solution, and effective latent heat of fusion was derived from latent heat of fusion of pure ice, effects of freezing-point depression, and dilution heat.     

Influence of surface roughness on the bonding quality in twin-roll cast clad strip

Manufacturing of aluminum-steel clad strips by means of twin-roll casting is of great interest due to a shorter production chain in comparison with convenient technologies. Experiments on twin-roll casting of clad strips of pure aluminum and an austenitic stainless steel of 2.5?mm total thickness with the inline abrasive cleaning of a steel substrate’s surface performed. The corresponding device for the inline surface preparation is designed. The influence of surface roughness of the substrate’s surface on the bonding strength between strip layers is analyzed. The mechanism of intermetallic bonding on the roughened surfaces is discussed. It is shown that surface roughness of steel substrate up to 4.2?µm provides bonding strength above 100?MPa.     

Beitrag zur Untersuchung des Ermüdungsverhaltens von Koronarstents

Comments to the Investigation of Fatigue Properties of Coronary Stents Since 1986 PTCA with implantation of a stent became a more and more important invasive method of treatment for coronary heart disease. The stent implanted during PTCA has to sustain a combined load of mechanical and chemical load. The pulsating artery leads to an expansion and cyclic mechanical load on the implanted stent. To eliminate the possibility of fail in vivo stents have to be tested regarding fatigue behaviour. As result of the complex geometry and the up to now not well investigated qualities of oligocrystalline structures [1], so far fatigue properties of stents can only be carried out on the implants themselves. Additionally stent design plays a decisive role in terms of mechanical factors.     

Predicting the viscosity of liquid refrigerant blends: comparison with experimental data

A method is presented for predicting the viscosity of liquid refrigerant mixtures. The method has no adjustable parameters and, in essence, relies upon the knowledge of the viscosity of the pure components to predict the viscosity of a mixture by means of kinetic theory and rigid-sphere formalism. The predictions have been compared with the available experimental data for a number of refrigerant mixtures. Based on this comparison and previous studies, the accuracy of the proposed method is assessed to be of the order of ±7%.     

The Overcoat Oil Lubrication of Microarc Oxidation Coating on Al Alloy by Liquid Plasma Technique

Ceramic coatings were deposited on 2Al2 alloy with a 100 kW micro-arc oxidation equipment consisting of a potential adjustable ac power supply and alkali electrolyte. The structure of the micro-arc oxidiation coatings was examined using scanning electron microscopy and transmission electron microscopy. The tribological properties of the coatings sliding against steel under the drop and adsorption lubrication of liquid paraffin were evaluated with a Timken tester. The lower friction coefficient of 0.14 and longer wear life of 2450 m of overcoat were observed for the polished micro-arc oxidation coating of 180μm thick at a sliding speed 2. 50 m/s and load 1500 N. This is because the coating has an interlayer of suitable porosity and thickness, which helps to improve the deposition of lubricants and endure the higher load. In other words, the oil is able to adsorb in the porous holes of the overcoat and provided the lubrication of micro reservoir during friction, and the compact and relatively hard interlayer of oxidation coating is able to support heavy load and prevent the oil lubricating film from damage.     

On mechanics of deformation and crushing processes

The mechanics of crushing and breaking of particles is one of the most intractable problems in materials science. The stressed states of processed materials are significantly inhomogeneous, and thus the deformation and disintegration mechanisms vary greatly. Two techniques have been developed for realizing these processes as a quasi-homogeneous transition. The device and method developed by Enikolopian transform a solid polymer spontaneously into powder. The same loading system is now used for obtaining fine-grained metals, similarly as when using the ECAP device developed by Valiev. Both techniques are now used for obtaining nanostructured materials. The common feature of both types of methods is the formation of new physical surfaces. These are particle-free oversurfaces or grain boundaries. The method requires a supply of energy in the form of mechanical work, and this is mostly done by simultaneous action of pressure and shear stress. The formation of free oversurfaces in stressed solid bodies is the subject of fracture mechanics. The Griffith equation is employed to describe the problem. __________ Translated from Problemy Prochnosti, No. 1, pp. 64–68, January–February, 2008.     

Central Venous Catheter Associated Infections Pathophysiology,Incidence, Clinical Diagnosis,and Prevention – A Review

The incidence of catheter related bloodstream infections poses a substantial burden on patient’s life’s and well‐being. Estimated 2 – 6 % of patients suffer from catheter associated bloodstream infections (BSI). Reports on mortality of these patients are up to 30 % in addition to a substantial prolongation of hospital days. The estimated cost of therapy of a BSI is approximately 10 000 € per patient. There is a definitive need for antimicrobially active medical devices for prophylaxis. Endowment of catheters with antibiotics and desinfectants have substantial limitations regarding spectrum of activity, duration of activity and clinical efficacy. The oligodynamic activity of silver has the greatest potential for prevention of catheter related infections. Various technologies in particular surface coating of these medical devices have been advocated previously with limited success. A new technology with impregnation of the entire catheter matrix with billions of nanoparticles of silver⁰ which results in a surface of 2000 cm²/g polyurethane (PU) has been developed. Central venous catheters manufactured according to the technology of the first and second generation have been investigated with good results of antimicrobial activity and biocompatibility. Favorable results in experimental investigations and good clinical results in controlled prospective, randomized, investigator blinded studies of the first generation silver catheter have been obtained. In 660 patients in an overall reduction of BSI of 66 % was observed. Favorable results in a postmarketing surveillance with 3000 patients were seen. The premarketing surveillance of the second generation silver‐catheter indicated an even greater reduction of catheter related BSI. In 204 patients with a mean duration of catheter placement of 9.2 days only one catheter related BSI was diagnosed. The rate of catheter colonization was <10 %. The catheter was well tolerated. A further improvement with increased antimicrobial activity was achieved by activation of silver nanoparticles in the third generation catheter: The superior results of in vitro tests and excellent biocompatibility lets us expect an additional improvement of preventive measures. The duration of antimicrobial activity has been investigated and lasts at least 370 days. The concept of impregnation of a polymer matrix and silicone can be extended to various other clinical applications e.g. Sheldon, Hickman and urologic catheters. Substantial savings in the cost of patient care through prevention of complications can be expected which is of particular importance with the disease oriented (DRG) remuneration system.     

Effect of applied voltage and electrolyte parameters on pitch,runout, flank topology,and finishing productivity of the straight bevel gears in PECH process

This paper describes improvements in the considered parameters of micro-geometry: flank surface topology and finishing productivity of 20MnCr5 alloy steel straight bevel gears through their finishing by pulsed electrochemical honing (PECH) process. Effects of three most important parameters of PECH process, namely applied voltage, electrolyte composition, and electrolyte concentration were investigated to identify their optimum values. Pre-identified values of other PECH parameters and an aqueous mixture of NaCl and NaNO₃ as an electrolyte were used in the present work. Errors in pitch (i.e., single pitch error, adjacent pitch error, and cumulative pitch error) and runout were used to evaluate micro-geometry of the straight bevel gears while volumetric material removal rate was used to judge the finishing productivity of the PECH process. Topology of the gear tooth flank surface and microstructure of the best-finished bevel gears were also studied. The results revealed considerable improvements in the micro-geometry, flank surface topology, and microstructure of the bevel gears finished by PECH. Applied voltage of 8?V, electrolyte composition of 75?wt.% NaCl?+?25?wt.% NaNO_3, and electrolyte concentration of 7.5?wt.% were identified as the optimum values to achieve simultaneous improvement in all the considered responses.     

The Study of Low Surface Energy Fluorocarbon Coatings with Fluor Content Being Lower

A kind of low surface energy fluorocarbon coatings from the synthesized fluoro-acrylic resin was developed.The molecule orientation principle of nonpolar and polar functional groups in the coatings was analyzed. The contact angles of pure water drops on the surfaces of various fluoro-monomer homopolymers and interpolymers were measured. The relation of coatings' fluoro-content with the surface energy was determined. The distribution of fluoric functional groups in the coatings was investigated. The test results show that though the total content of fluor of the fluorocarbon coatings is relative few, their surface energy is really low due to the enrichment of fluoro-chains on the surfaces.