热焊弯管用钢板工艺探讨

在统计分析、正交多项式回归和模拟试验的基础上，建立了高精度的屈强比预报模型，并运用多元函数极值原理，求导极值点及相应的工艺参数，为优化工艺制度，提高热焊弯管用钢(L360-WG系列)性能合格率提供了定量依据。     

Effects of different cooking methods on the formation of food mutagens in meat

Hamburgers and chicken fillets were cooked in convection ovens, deep‐fried or contact fried and analysed for mutagenic activity using the Ames test. For the three different convection ovens, the cooking parameters studied included the presence of steam, air velocity, air temperature and holding time. For deep‐frying and contact frying, the cooking parameters included cooking temperature and cooking time. In cooked hamburgers, mutagenic activity was only detected in those that had been deep‐fried. In chicken fillets, mutagenic activity was detected in samples prepared with all cooking methods, being highest in the deep‐fried samples. Factorial analysis indicated that heat transfer was the most important factor affecting mutagenic activity. High temperature and high air velocity in the convection ovens enhanced mutagenic activity. The presence of steam reduced the mutagenic activity, except when high temperature was used in combination with high air velocity. In chicken fillets, high mutagenic activity correlated to high weight loss during cooking. Pan‐fried chicken fillets were analysed using high performance liquid chromatography (HPLC) and the mutagenic/carcinogenic heterocyclic amines 2‐amino‐3,8‐dimethylimidazo[4,5‐f ]‐quinoxaline (MeIQx), 2‐amino‐1‐methyl‐6‐phenylimidazo‐[4,5‐b]‐pyridine (PhIP) and the co‐mutagenic heterocyclic amine Norharman (9H‐pyrido[3,4‐b]‐indole) were identified. The HPLC fractions were tested for mutagenic activity and, apart from the mutagenic fractions corresponding to MeIQx and PhIP, several mutagenic fractions were detected that did not correspond to known heterocyclic amines.     

维氏硬度检测中不确定度初探

通过分析维氏硬度检测中的不确定度，计算了各不确定度分量所占的权重，得到HVlO(440--738)范围内的相对不确定度为1．3％--1．7％。     

Self-controlled case series analyses: Small-sample performance

Second-order expressions for the asymptotic bias and variance of the log relative incidence estimator are derived for the self-controlled case series model in a simplified scenario. The dependence of the bias and variance on factors such as the relative incidence and ratio of risk to observation period are studied. Small-sample performance of the estimator in realistic scenarios is investigated using simulations. It is found that, in scenarios likely to arise in practice, asymptotic methods are valid for numbers of cases in excess of 20-50 depending on the ratio of the risk period to the observation period and on the relative incidence. The application of Monte Carlo methods to self-controlled case series analyses is also discussed.     

A disposable single-use electrochemical sensor for the detection of uric acid in human whole blood

We report here a non-enzymatic detecting electrode strip for fast monitoring of uric acid in human whole blood. A single-use amperometric uric acid sensor strip, incorporating a three-electrode configuration, has been fabricated on a polypropylene substrate using low cost screen-printing (thick-film) technology. Both the working and counter electrodes were prepared by screen-printing commercial carbon ink. The integration on the same support of pseudo-reference electrode was obtained by screen-printing a commercial silver ink and subsequent electrochemical pretreatment. Simply by placing a 20 μl human whole blood drop on the strip is enough for uric acid analysis by square-wave voltammetry. Real human whole blood samples were analyzed by this method and compared to the phosphotungstic acid clinical test procedure with satisfactory results.     

广播电视发射台技术指标集中自动测试系统

本文介绍了利用计算机技术、网络技术、三遥技术对广播电视发射技术指标进行实时自动测试的系统，以便进一步为安全优质播出提供技术保证。     

高应力水平下滚动轴承疲劳寿命试验研究

通过在三种不同的强化负荷下进行深沟球轴承疲劳寿命试验，并与常规试验一组结果对比。结果表明，适当地加大滚动轴承疲劳寿命试验负荷，可以大大缩短试验时间，而疲劳寿命依然服从Ｗｅｉｂｕｌ分布，且与常规试验结果基本一致，同时疲劳破坏的形式仍是表面下萌生裂纹，然后扩展至表面形成剥落。     

铸造高性能合金的显微组织及耐腐蚀行为

对铸造高性能合金Lewmet55进行了化学成分设计，确定了该合金中镍、铬、钼、铜和硅的含量。采用金相显微镜和X射线衍射相结合的方法，分析了该合金的显微组织，并采用多种腐蚀试验方法研究其耐腐蚀行为。着重研究了不同热处理制度对铸造高性能合金的均匀腐蚀、晶问腐蚀、点蚀和电化学腐蚀性能的影响。试验结果表明，Lewment55合金经1250℃×1．5h水冷固溶处理后，在高温浓硫酸介质中具有良好的耐蚀性，以及较好的抗晶间腐蚀、点蚀和电化学腐蚀性能。     

50kg／m钢轨轨底缺陷的检验和分析

钢轨轨底缺陷有三种：底伤、结疤和底裂缺陷。取２０根有底缺陷５０ｋｇ／ｍＵ７１Ｍｎ钢轨做试样，通过低倍、断口、金相检验和扫描电能谱分析，详细描述了轨底缺陷的宏观和微观特征，研究出钢轨轨底缺陷出现的规律臁其产生的原因。通过对比试验，发现淄博１号保护渣有利于改善钢锭表面质量，提高钢轨一级品率。     

SW233 PIN驱动器自动测试系统的研制

介绍了一种集成电路自动测试系统，该系统采用计算机并口作通信接口，用VB6编程，实现了对外围测试电路的控制，用IEEE-488接口卡控制测试仪器，可对SW233电路的36个参数进行自动测试，并将测试结果自动保存在数据库中。该测试系统具有自动化程度高、操作方便、测试结果精确等特点。