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331.
降低工具和机器效率的一个主要原因是金属磨损,磨损也能引起机器准确率降低。如何提高机器耐磨性,研究机器磨损的规律是很重要的。介绍了金属磨损的类型,实验室磨损试验的方法,磨损试验的磨损量测量方法及表示方法。  相似文献   
332.
Methane emission monitoring has become increasingly essential for diffusive area sources, especially for landfills, which contribute to a significant fraction of the total anthropogenic methane emission globally. Statutorily, methane emission rate from landfills in Germany shall be examined on a semiannual basis; however, an appropriate approach has yet to be developed and adopted for general use. In this study, a new method is proposed based on experimental results, which utilizes a TDLAS (Tunable Diode Laser Absorption Spectroscopy) instrument – GasFinder2.0® system and a dispersion model LASAT (Lagrangian Simulation of Aerosol Transport) as the measurement device and calculation model, respectively. Between April 2010 and December 2011, a research project was conducted at a pilot scale landfill in the south of Germany. Drawing on the extensive research into this pilot project, an effective strategy of measurement setup was determined. Methane concentration was measured with GasFinder2.0® system in the upstream and downstream sections of the project site, while wind and turbulence data were measured simultaneously by an ultrasonic anemometer. The average methane emission rate from the source can be calculated by using the results as input data in the dispersion model. With this method, site-specific measurement approaches can be designed for not only landfills, but also different diffusive area sources with less workload and lower cost compared to conventional FID (Flame Ionization Detector) method.  相似文献   
333.
蒸散量测定与估算方法的对比研究   总被引:34,自引:1,他引:33  
以涡度相关法的实测资料为标准,对波文比-能量平衡法、空气动力学法、Penman-Monteith模型、Shuttleworth-Wallace模型进行对比研究,并分析了各种方法的精度和灵敏度。结果表明:Penman-Monteith模型和波文比-能量平衡法的精度最高,Shuttleworth-Wallace模型和空气动力学法的精度较差。Penman-Monteith模型的稳定性较好,波文比-能量平衡法受Δe和ΔT观测精度的影响大,风温湿观测高度以及下垫面是否均一对空气动力学法影响较大,Shuttleworth-Wallace模型对各类阻抗较为敏感。  相似文献   
334.
The main purpose of this study was to develop a set of measures for evaluating the performance of the automobile green supply chain. This study reviewed various literatures on green supply chain performance measurement, environmental management, traditional supply chain performance measurement, and automobile supply chain management. In order to comprehensively and effectively establish the relevant measures, a suitable framework which considered the automobile green supply chain as a two-in-one chain was adopted. This two-in-one chain comprised a forward and backward chain for the automobile industry. Consequently, 10 measures with 49 metrics and 6 measures with 23 metrics were identified and developed for the forward and backward chains, respectively. Sequel to the development of these measures, a survey was conducted using a four-page questionnaire distributed to experts (including academics and practitioners) to establish their importance and applicability. The findings of this study suggested that the importance and applicability of all the developed measures have been substantiated. For the forward chain, the most crucial measure was customer perspective while the most applicable one was traditional supply chain cost. The reverse chain measures were topped by management commitment in terms of both importance and applicability. This study contributed to the advancement of knowledge by pioneering the development of a set of holistic measures for evaluating the performance of the automobile green supply chain. The study was wrapped up with the proposition of directions for further studies.  相似文献   
335.
This study was conducted because a real method for measuring safety climate had never been developed and assessed in Serbian industry. The aim of this paper was to start the process of developing a safety climate questionnaire that could be used in Serbia. As a starting point a 21-item questionnaire was adopted after an extensive literature review. The questionnaire was distributed at several Serbian factories; 1098 workers responded. After a statistical analysis of the data obtained with the questionnaire and a critical comparison with the available reference results, a final questionnaire with 21 questions, divided into 7 groups, was developed. The 7 groups of questions (factors) were safety awareness and competence, safety communication, organizational environment, management support, risk judgment and management reaction, safety precautions and accident prevention, and safety training.  相似文献   
336.
大气中硝酸(HNO3)的生成是排放到空气中氮氧化物(NOx)的主要沉降途径,对降水酸化、二次细颗粒物中硝酸盐的形成以及在研究光化学污染和霾形成等大气复合污染过程之间的联系中具有重要作用.获得高时间分辨率、准确的大气HNO3测量数据对研究和认识大气中NOx的循环机理是十分必要和迫切的.大气中的HNO3浓度低且具有很强的吸...  相似文献   
337.
围绕现行的GB12348—2008《工业企业厂界环境噪声排放标准》在厂界噪声测量中测量指标不明确、方法简单、测点位置未细化等问题,通过对增压站、集输站等进行厂界噪声测量,对存在问题进行分析探讨,提出解决这些问题的方法与改进建议。  相似文献   
338.
文章研究了在同一样品溶液中连续测定亚铁和总铁的分析方法,对同一标准样品溶液和实际样品进行了单独测定亚铁和总铁含量的实验,同时在完成亚铁含量测定后加入试剂,进行了总铁含量的连续测定,并对实验数据进行相对误差分析。结果表明:单独和连续测定的总铁含量数据无显著性差异,方法切实可行。  相似文献   
339.
在压力容器的超声检测中,为解决传统相控阵(PA)二维成像存在缺陷图像畸变,难以准确定性等问题,采用1种基于全聚焦法(TFM)的实时超声成像技术,使用一维线阵和二维面阵分别对孔等典型实际缺陷进行扫查,获得缺陷的二维和三维图像,从定量角度对比分析2者的准确度。结果表明:该方法获得的三维图像测量误差在8%以内,具有更高的精确度和检出率,对于孔类缺陷的还原度更高,这对于缺陷检测与评估以及和特种设备的安全生产具有重要意义。  相似文献   
340.
地面风场风速测量标准装置需求与设计   总被引:1,自引:1,他引:0       下载免费PDF全文
针对地面风场中风速测量仪器计量测试的需求,提出了风速测量标准装置的组成及性能指标设计要求,详细分析了风速测量标准装置各个重要部件的设计关键技术,结果表明该设计科学合理。  相似文献   
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