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1.
对比不同热电厂企业工人接触职业危害因素情况,分析原因,为在建或已建热电厂提供职业危害因素预防措施,降低企业由于设计、施工或管理方面原因造成后期运行过程中职业危害接触超标情况的发生。根据我室历年对新疆地区热电厂职业危害因素检测结果与评价报告的比较,找出不同热电厂职业病危害因素的共性及异性,分析不同设备、工艺及管理方式不同所造成职业危害因素检测结果的差异及原因。建议优化厂区工艺及土建设计;优化设备选型及原料选择运用现代化的管理手段,加强职业卫生管理体系宣贯的有效运作。 相似文献
2.
Qiaozhi Zhang Yanbo Wang Linglin Fu 《Comprehensive Reviews in Food Science and Food Safety》2020,19(5):2559-2587
Dietary advanced glycation end products (dAGEs) are complex and heterogeneous compounds derived from nonenzymatic glycation reactions during industrial processing and home cooking. There is mounting evidence showing that dAGEs are closely associated with various chronic diseases, where the absorbed dAGEs fuel the biological AGEs pool to exhibit noxious effects on human health. Currently, due to the uncertain bioavailability and rapid renal clearance of dAGEs, the relationship between dAGEs and biological AGEs remains debatable. In this review, we provide the most updated information on dAGEs including their generation in processed foods, analytical and characterization techniques, metabolic fates, interaction with AGE receptors, implications on human health and reducing strategies. Available evidence demonstrating a relevance between dAGEs and food allergy is also included. AGEs are ubiquitous in foods and their contents largely depend on the reactivity of carbonyl and amino groups, along with surrounding condition mainly pH and heating procedures. Once being digested and absorbed into the circulation, two separate pathways can be involved in the deleterious effects of dAGEs: an AGE receptor‐dependent way to stimulate cell signals, and an AGE receptor‐independent way to dysregulate proteins via forming complexes. Inhibition of AGEs formation during food processing and reduction in the diet are two potent approaches to restrict health‐hazardous dAGEs. To elucidate the biological role of dAGEs toward human health, the following significant perspectives are raised: molecular size and complexity of dAGEs; interactions between unabsorbed dAGEs and gut microbiota; and roles played by concomitant compounds in the heat‐processed foods. 相似文献
3.
Using a comprehensive set of drop weight impact test data (h50) newly compiled from literature for 308 materials, a recent approach to predict impact sensitivities of nitro compounds is generalized to most explosive substances of interest. Compared to previous ones, this procedure is more thoroughly validated and exhibits a good predictive value. Furthermore, it yields new insight into the physical mechanisms involved, explaining for instance the unexpected desensitization of some oxygen-deficient triazoles upon nitration. 相似文献
4.
Occupational airway diseases are now receiving attention in industry, although study is hampered by a lack of readily-available data. The interpretation of the data that is available, and also of the root problems themselves, is itself a difficult problem. This paper has been written as a literature review which it is hoped that other researchers can take either as a starting point or as a refresher. 相似文献
5.
The philosophy behind quality, environmental, and safety (QES) management systems is a concept that has been accepted by various contractors. Furthermore, a process has been developed insuring that the output produced conforms to customer satisfaction without violating any environmental, health, and safety rules and regulations. An effective QES program not only assures a quality product but also reduces costs, and enhances productivity. It is a top down process, i.e., top management together with line management and other employees develop the program and motivate all personnel to accept the process. Important functions to take under consideration are (1) explain and clarify the quality, environmental, and safety performance expected; (2) involve employees in decision-making and problem solving; (3) describe the consequences of poor quality and unsafe/unhealthy work conditions; (4) establish QES goals and provide feedback on performance; (5) provide a self-monitoring system; and (6) recognize and reinforce good performance and develop a reward system. This paper presents a discussion of the development of a portion of a QES management system which has been employed by a medium to large size construction company. In particular, Items 1–4, listed above, are described in detail. 相似文献
6.
为了提高滚动轴承剩余寿命预测的准确性,根据滚动轴承运行过程的两阶段性特点,提出了一种基于蝙蝠算法(BA)和威布尔比例风险模型(WPHM)的滚动轴承两阶段剩余寿命预测方法。首先,构建基于WPHM的剩余寿命预测模型;其次,提出了两阶段极大似然估计法,建立新的似然函数,并利用BA算法进行求解,以提高参数估计的准确性;最后,建立BA-WPHM模型对滚动轴承进行剩余寿命预测。案例分析表明,相比于Newton-Raphson算法、自组织分层猴群算法(SHMA)和独特的自适应粒子群算法(UAPSO),提出的方法参数估计的准确性更高,剩余寿命的预测精度优于支持向量回归(SVR)方法,验证了所提方法的有效性,为滚动轴承维修决策的可行性提供了依据。 相似文献
7.
Due to advances in medical research, more and more diseases can be cured nowadays, which largely increases the need for an easy-to-use software in calculating sample size of clinical trials with cure fractions. Current available sample size software, such as PROC POWER in SAS, Survival Analysis module in PASS, powerSurvEpi package in R are all based on the standard proportional hazards (PH) model which is not appropriate to design a clinical trial with cure fractions. Instead of the standard PH model, the PH mixture cure model is an important tool in handling the survival data with possible cure fractions. However, there are no tools available that can help design a trial with cure fractions. Therefore, we develop an R package NPHMC to determine the sample size needed for such study design. 相似文献
8.
李慧平 《自动化与仪器仪表》2014,(6):124-126
目前我国工业供电系统中越来越多地使用电力电子设备,这些设备会导致供电系统谐波含量增多,电能质量下降,并对其他用电设备造成不良影响。鉴于此,本文阐述了电网谐波抑制的重要性、紧迫性及谐波抑制方法,分析了有源滤波器的工作原理,并通过具体实例介绍其应用情况。 相似文献
9.
随着信息应用水平的提高,以及网络普及程度的加深,电子信息产品也逐渐地走入人们的生活,给人们带来了许多的方便。但是电子信息产品也面临一系列的数据安全隐患,数据和信息一旦泄露,会给国家、机构、个人造成不小的损失。因此,必须对电子信息产品的数据安全隐患进行探究,并且采取强有力的措施来进行预防。笔者根据实际情况,针对电子信息产品数据安全隐患进行了分析,希望能为广大的相关工作者提供一些参考依据。 相似文献
10.
随着我国经济的快速增长和人民生活水平的提高,改善物质与生活条件和营造出满足精神所需的居住环境气氛是人们提高生活质量的新需求,也成为当前一种趋势和时尚.为此,人们普遍重视装修形式的新颖与材料设备的选择风格,却往往忽视违规装修引起的安全问题.由于缺乏装修知识及安全意识,忽视房屋结构的整体性、耐久性及抗震性,根据个人意愿肆意改拆,从而导致各种事故和安全隐患日趋严重.鉴于上述情况,本文详实地分析不规范装修行为及其带来的危害,揭示其产生的原因,提出改进当前违规装饰装修的具体措施,为推进我国房屋装饰装修行业的健康发展,延长建筑使用寿命、保障人们身心健康和安全具有重要意义. 相似文献