企业全员危险源管理实践

为了预防企业生产安全事故发生,围绕危险源的管理,综合运用多种安全评价方法,通过小组活动自下而上开展全员危险源辨识、风险评价、现有风险控制措施评估,结合危险源辨识成果随机抽查、行为安全观察等管理活动,形成了企业全员危险源管理的企业文化氛围。对开展全员危险源管理1年以上的13家不同类型企业进行安全文化绩效评估,结果显示,开展THM对安全行为、安全教育、全员参与等安全文化绩效评价指标有显著提升作用。     

Measurement of minimum ignition energies (MIEs) of dust clouds – History,present, future

Nearly 130 years ago Holtzwart and von Meyer (1891) demonstrated by experiments that explosible dust clouds could be ignited by inductive electric sparks. Then more than half a century passed before the publication of the important quantitative research of Boyle and Llewellyn (1950) and Line et al. (1959). They worked with capacitive electric sparks and found that the minimum capacitor energies ½CU² required for ignition of various dust clouds in air decreased substantially when a large series resistance, in the range 10⁴–10⁷ Ω, was introduced in the discharge circuit. When considering that the net energies of the sparks themselves were only of the order of 10% of the ½CU² discharged, the minimum net spark energies required for ignition with a large series resistance were only a few per cent of the net energies required without such a resistance.Line et al. observed that the essential effect of increasing the series resistance, and hence increasing the discharge time of the sparks, was to reduce the disturbance of the dust cloud by the blast wave from the spark. This phenomenon was explored further by Eckhoff (1970, 2017), and subsequently by some simple experiments by Eckhoff and Enstad (1976). Franke (1974, 1977) and Laar (1980) confirmed the additional finding of Line et al. (1959) that the minimum ½CU² for ignition is also substantially reduced by including a series inductance in the discharge circuit, rather than a series resistance. The basic reason is the same as with a large series resistance, viz. increased spark discharge time and hence decreased disturbance of the dust cloud by blast wave from the spark. For this reason inclusion of an appreciable series inductance in the spark discharge circuit is an essential element in current standard MIE test methods.In experiments with spark ignition of transient dust clouds produced by a blast of air in a closed vessel, it is necessary to synchronize the occurrence of the spark with the formation of the dust cloud. The precision required from this type of synchronization is typically of the order of 10 ms, which can be obtained even by mechanical arrangements, such as rapid change of spark gap length, or of the distance between two capacitor plates. The present paper reviews some methods that have been/are being used for achieving adequate synchronization of dust cloud appearance and spark discharge. Some current standard experimental methods for determining MIEs of dust clouds experimentally have also been reviewed. The same applies to some theories of electric-spark ignition of dust clouds.At the end of paper some suggestions for possible future modifications of current standard methods for measuring MIEs of explosible dust clouds are presented. With regard to justifying significant modifications of existing standard methods, the “bottom line” is, as quite often in many connections, that any modifications should be based on realistic cost/benefit evaluations.     

精密离心机静态半径测量不确定度的温度特性分析

目的研究温度对精密离心机静态半径测量不确定度的影响。方法以静态半径测量反算法为基础,推导静态半径测量不确定度的温度特性模型,设计精密恒温装置,并进行试验,获取加速度计在1 g离心机场下不同温度时的输出数据,并进行分析。结果基于温度特性模型,确定了影响静态半径测量不确定度的主要因素。试验数据结果表明,在加速度计工作范围内(50~60℃),静态半径测量不确定度随温度递增呈现“先增后减”的分布规律,且在50℃时进入到了10‒7量级。结论加速度计的温度敏感性是影响静态半径测量不确定度的最主要因素,精密控温能显著提高静态半径测量精度。     

中国石油污染源普查数据质量控制方法

污染源普查数据是污染源普查成败的重要决定因素和普查成果的主要体现。文章对中国石油在污染源普查过程中发现的数据质量问题进行分析,提出质量控制方法,通过开展技术培训和交流、建立四级联审体系、强化数据审核与质量核查、建章立制严格考核等方法进行全过程质量控制,确保了中国石油污染源普查数据质量达标,普查工作圆满完成。     

Phosphate removal using aerobic bacterial consortium and pure cultures isolated from activated sludge

In the present study, an attempt is made to evaluate the kinetics of biological phosphate removal using a bacterial consortium of activated sludge, as well as screening for dominant polyphosphates accumulating bacteria. The results showed an efficient phosphate uptake (P < 0.001) of the consortium, with rates related to the initial concentration of both phosphate and carbon sources. Short chain volatile fatty acids presented the suitable substrates for enhanced biological phosphorus removal, of which maximum yield reached 99.23% and 78.51% in basal salt medium supplemented with 0.5% of sodium acetate and lactate respectively. Fifteen phosphate-accumulating bacteria were isolated from the activated sludge and only four isolates were selected and characterized as Pseudomonas aeruginosa AS1, Moraxella lacunata AS2, Acinetobater junii AS3 and Alcaligenes denitrificans AS4. The highest efficiency of phosphate uptake using pure culture was achieved with Ac. junii AS3 (83.36) followed by P. aeruginosa AS1 (81.78%), Al. denitrificans AS4 (76.72%), and M. lacunata AS2 with 50.6%.     

生物-物化法治理稀黑液工艺

提出了以从自然界分离得来的组合菌CG、WD,结合物化法治理稀黑液的工艺方法.结果表明,1.5°Be′左右的稀黑液经本工艺处理,硫化物、挥发酚去除率均达99%以上,色度、CODcr和BOD     

三峡地区农业经济监测原理与方法研究

提出了经济系统抟动监测原理,认为受扰动Ｘ作用的系统Ｓ的特征指标（监测指标）Ｏ的变化量△Ｏ分为由系统Ｓ自身发展引起的变化量△Ｏ和由扰动Ｘ的作用引起的变化量△Ｏｘ,即△Ｏ＝△Ｏ＋△Ｏｘ,监测的目的是考察由扰动Ｘ引起的指标Ｏ的变化量△Ｏｘ,提出了建立经济系统监测指标体系。针对５项原则和三峡地区农业经济指标体系。针对不同系统特点和扰动特性,提出８种监测方法。以对三峡库区秭归县水田坝乡眩坝区域柑桔产业开发对     

Regional environmental assessment (REA) and local Agenda 21 implementation

The implementation of sustainable development requires several support instruments. One of the major instruments in the Rio Declaration to support this process has been environmental assessment that has been given considerable emphasis as to its potential ability to help achieve more sustainable forms of development. Regional environmental assessment (REA) has shown to be effective in supporting local sustainable development process. Selected environmental assessment methods have been␣used to improve the REA exercise and provide reliable data for decision-making not only to correct environmental problems due to past unsustainable social-economic developments but also help local governments to implement Agenda 21 (AG21) plans and projects.     

Subjective modeling choices and the robustness of impact evaluations in conservation science

Arbitrary modeling choices are inevitable in scientific studies. Yet, few empirical studies in conservation science report the effects these arbitrary choices have on estimated results. I explored the effects of subjective modeling choices in the context of counterfactual impact evaluations. Over 5000 candidate models based on reasonable changes in the choice of statistical matching algorithms (e.g., genetic and nearest distance mahalanobis matching), the parametrization of these algorithms (e.g., number of matches), and the inclusion of specific covariates (e.g., distance to nearest city, slope, or rainfall) were valid for studying the effect of Virunga National Park in Democratic Republic of the Congo on changes in tree cover loss and carbon storage over time. I randomly picked 2000 of the 5000 candidate models to determine how much and which subjective modeling choices affected the results the most. All valid models indicated that tree cover loss decreased and carbon storage increased in Virunga National Park from 2000 to 2019. Nonetheless, the order of magnitude of the estimates varied by a factor of 3 (from −4.78 to −13.12 percentage points decrease in tree cover loss and from 20 to 46 t Ce/ha for carbon storage). My results highlight that modeling choices, notably the choice of the matching algorithm, can have significant effects on point estimates and suggest that more structured robustness checks are a key step toward more credible findings in conservation science.     

城市环境管理中的环境文化与环境道德--城镇垃圾分类收集的施行

阐述环境文化与环境道德这两个概念,并且分析其优缺点以及在城市环境管理中的作用,同时以垃圾分类收集为例,阐述了环境文化和环境道德的具体应用。