连铸机结晶器使用寿命的提高

连铸机结晶器使用寿命的提高据Сталь１９９６年第７期报道，提高连铸机工作效率的方向之一是延长铜质结晶器的使用寿命，为实现这一目的必须防止形成结晶器宽壁和窄壁之间的缝隙或不刮掉铜而清除缝隙。铜表面的挤压和摩损主要出现在窄壁上。缝隙基本上出现在弯月面上...     

Effect of zeranol on bull muscle fibre composition

Two trials are reported in which bulls were implanted with zeranol and slaughtered at 18 months. There was no significant change in carcass weight due to zeranol in either trial. Samples of the longissimus dorsi (LD) and splenius (Sp) were cross-cryosectioned, stained for myofibrillar ATPase and examined by conventional light microscopy. The stain resolved three fibre types: I, slow contracting with an oxidative metabolism, IIA, fast-oxidative-glycolytic and IIB, fast-glycolytic. In the LD from treated bulls, the occurrence of IIB fibres was increased, apparently at the expense of IIA fibres, as the occurrence of I fibres was unchanged. These occurrence changes parallelled previously reported effects of castration. Changes in Sp were less dramatic. In one trial IIB fibres were absent from all Sp muscles, but, in the other, some of the Sp muscles from treated animals contained these fibres whereas they were absent from the Sp of the control group. If the changes in fibre type occurrence due to zeranol extend to skeletal muscles other than LD and Sp, there is likely to be a subtle change in the musculature's metabolism. Fibre areas were largely unaffected by zeranol. In this respect zeranol did not mimic castration.     

广西长洲水利枢纽工程高压喷射灌浆工艺研究

介绍了四种高喷工艺(单管法、两管法、三管法、二次切割法)在三种喷射方式(定、摆、旋)下处理粉细沙层的情况,通过对试验参数、试验成果进行分析、描述,获得了各种高喷工艺在粉细沙层中成墙的资料,供同行参考。     

基于MVC模式的医疗设备信息管理系统的设计与开发

医疗设备信息化管理是提升医院管理水平的重要手段。随着医疗设备的增多,设备管理信息化成为医院信息化的一个新环节。为提高医疗设备管理的现代化、科学化和规范化水平,提出了医疗设备信息管理系统的设计和开发方案.较为详细地分析了基于MVC模式的医疗设备信息管理系统的设计意义、系统构架、系统分析、功能模块。在一年的应用当中,系统提供了准确、及时的设备管理信息,提高了医院医疗设备的管理水平。     

Towards a standard in assessment of bone cutting for total knee replacement

Arthroplasty outcome is influenced by the 'quality' of bone preparation for implant insertion. Surgeons face increasing choices of technique and instrumentation, yet clinical scoring methods assess the overall outcome and patient satisfaction but not the bone cuts directly. 'Quality management' of bone reshaping is needed to evaluate different bone cutting methods and computer assisted orthopaedic surgery (CAOS) systems. Analyses and experiments in this study were formulated for measurement and computation of four quantitative characteristics of bone preparation 'quality' and produced a highly condensed index for each. These represented (a) surface finish of cuts, (b) implant fit/looseness possible with the cut shape, (c) implant location/misalignment, and (d) accuracy of individual planar cuts. Assessment of synthetic bone cuts verified the robustness of the method for wide application in arthroplasty intraoperatively, in vitro and for comparing navigation systems.     

基于逻辑诊断理论的航空发动机起动系统故障诊断的应用

针对某型飞机发动机故障诊断中,故障现象与故障原因之间关系极为复杂、不确定,提出了该型发动机故障的逻辑诊断方法,建立了逻辑诊断的数值理论模型。根据以往方法建立逻辑诊断矩阵不足,提出了采用人工智能之方法,利用专家知识动态建立逻辑诊断矩阵过程模型。本文结合具体故障案例,在计算机上实现了该型发动机故障的逻辑诊断,验证了该方法诊断发动机系统故障的正确性。     

固结灌浆技术在观音岩水电站导流明渠施工中的应用

观音岩水电站坝区导流明渠段地质条件极为复杂,部分岩体钙质流失,溶蚀孔洞及溶蚀砂化带较为发育,地下水出露极为丰富。导流明渠基础固结灌浆对导流明渠导流的安全有重要影响。本文对明渠基础固结灌浆施工及施工中遇到的技术难点及对策进行了阐述。     

Tenderness of ovine semimembranosus: Is collagen concentration or solubility the critical factor?

The concentration and heat-dependent solubility of collagen were measured in the semimembranosus (36 animals) and, for comparison, the gluteus (108) muscles of sheep aged 4 months to 5 years. For both muscles, solubility declined with age but concentration remained unchanged. Compared to gluteus and other major ovine muscles, the semimembranosus had markedly insoluble collagen at a relatively low concentration. To assess the relative importance of collagen concentration and solubility on tenderness/texture for a muscle with this profile, the semimembranosus muscles contralateral to those used for collagen analysis were cooked to an endpoint of 75°C and assessed by sensory panel and Warner-Bratzler shear tests. The panel data showed that collagen concentration was the more important determinant of eating quality, whereas shear data were more clearly related to solubility. The implications of the sensory results are discussed for muscles that contain a different collagen profile.     

The effect of preheated tendon as a lean meat replacement on the properties of fine emulsion sausages

Tendon from beef hind leg muscles was used to replace some of the lean in a conventional emulsion formulation. The tendon was homogenized and either used raw or preheated for 2·5 h at a range of temperatures (50, 60, 70, 80°C) before use. Texture analysis and sensory evaluation were performed on cylinders of cooked sausage. Texture analysis was carried out on formulations which had 20% of meat protein replaced by 20% tendons which were raw or had been preheated to 50, 60, 70, or 80°C. Fracturability decreased by about 40% with raw tendon, but was restored to within 20% of the no-replacement control if the tendon had been preheated. Hardness was approximately doubled by replacement with raw tendon or tendon heated at 50°C. At temperatures higher than that, hardness returned to approximately no-replacement levels. For sensory evaluation (0-25% replacement; preheating at 70°C), sausages were assessed by a 12-member panel for texture, flavour and overall acceptability. All attributes decreased with increasing collagen content, the decrease being less marked with preheated tendon. Thus more connective tissue could be added for the same panel score if the tissue was preheated. Comparison of the texture profile and the panel scores for texture at the same lean replacement level suggested that reduced fracturability was the texture parameter that panellists objected to when heated tendon replaced some of the lean. Other researchers have shown that connective tissue preheated to 100°C before addition in emulsion sausages results in improved yields and better sensory attributes, but the present results show that temperatures as low as 60°C can be effective for beef tendon.     

The biochemical basis of fibre types in bovine muscle

Recent studies using isolated muscle fibres have established a link between the histochemical fibre types, I, IIA and IIB, which can be defined by myofibrillar ATPase activity, and three forms of myosin heavy chain. This work is reviewed, as is work on metabolic variability within these fibre types. Results are them presented which show that the activity of myofibrillar ATPase in sections, although principally determined by the myosin heavy chain, is modified by other myofibrillar components, as yet unidentified. Evidence is also presented for hybrids of myosin heavy chain in muscle fibres. Finally, metabolic variability within the fibre types is examined for bovine muscle. It is concluded that, in spite of wide metabolic variability within types, a classification based on myofibrillar ATPase activity is still useful.