易燃易爆场所静电事故链路及断链减灾模式

为了探究易燃易爆场所静电事故形成过程及防护机理,基于事故链式理论,以及静电点燃源形成过程和爆炸性环境形成过程这2条并行支链,绘制了易燃易爆场所静电事故链路;通过事故案例说明了静电事故链路的实用性;研究了静电荷、易燃/可燃物质在外界扰动作用下的特征形态。研究结果表明:静电事故断链减灾模式包括静电点燃源断链减灾模式、爆炸性环境断链减灾模式以及降低事故影响的事故后果断链减灾模式;针对静电事故的各类断链减灾模式,提出了相应的防护措施,可为易燃易爆场所静电事故防护提供系统性的指导方案。     

古典、现代事故致因链在我国煤矿事故分析中的比较研究

事故致因理论是事故的发生机理和理论模型,事故致因链是其核心,是导致事故发生的基本路线。通过对古典事故致因链的代表:海因里希因果连锁理论及现代事故致因链的代表:行为安全"2-4"模型的原因定义、组织概念的引入、链条逻辑关系、事故预防策略等多方面的比较,并应用于一起真实煤矿事故案例分析,发现行为安全"2-4"模型不仅继承和发展了因果连锁理论的优点,更是改进其缺点,在对我国煤矿事故案例分析中更加有效,且在各层级均可找到事故预防的策略。     

油酸钠对餐厨垃圾两相厌氧发酵中利用乙酸产甲烷过程的影响

为了研究餐厨垃圾油脂中含有的长链脂肪酸(主要是油酸)对两相厌氧发酵中利用乙酸产甲烷过程的影响,采用中温(35±1)℃批式发酵,以浓度为10 g·L~(-1)的餐厨垃圾厌氧发酵产甲烷相出水为接种液,以乙酸为底物,考察了添加不同浓度油酸钠对累积甲烷产量、产甲烷古菌数量以及发酵过程中乙酸代谢和氢气分压的影响.结果表明:1产甲烷延滞期随油酸钠浓度增加而延长.2油酸钠浓度低于6.0 g·L~(-1)的处理组经过延滞期后乙酸代谢恢复正常,可以完全被转化为甲烷,且部分油酸钠也可被转化为甲烷;油酸钠浓度高于8.0 g·L~(-1)的处理组乙酸代谢受到严重抑制,只有少量甲烷生成;油酸钠生成中间代谢产物,且甲烷转化率为0.3油酸钠对厌氧发酵中产甲烷古菌有严重的抑制作用,产甲烷古菌数量大幅度减少是乙酸代谢过程受到抑制的主要原因.4油酸钠的添加量超过6.0 g·L~(-1)时,在发酵初期会引起产甲烷相中氢分压的升高,也证实了油酸钠对厌氧发酵的抑制作用.     

Food access,food security and community gardens in Rockford,IL

Urban agriculture projects seek to ameliorate issues of food access and food security for people living in areas with low access to fresh foods, including food deserts. Within this discourse, community gardens have been promoted as vehicles to reclaim unused urban space, produce food locally and connect populations to their food sources and larger community. A variety of community garden models exist; in the Midwestern city of Rockford, Illinois, many community gardens grow food for donation to food pantries as part of a programme to benefit socioeconomically disadvantaged persons in the city. However, the ability of these gardens to involve neighbourhood participants and provide the social capital-related benefits attributed to community gardens in the literature is uncertain. Here we examine community gardens in Rockford, IL to assess the extent to which they contribute to residents’ ability to obtain fresh produce as well as other social benefits. Data for this project come from a combination of interviews with gardeners, focus groups with food pantry users and a survey of pantry users. We find that while non-gardening community members are benefitting from the increased produce that the gardens provide, they are not receiving all of the social and communal benefits associated with actively participating in a garden.     

Evaluation of vulnerability of Suillus variegatus and Suillus granulatus mushrooms to sequester mercury in fruiting bodies

This work determined the mercury (Hg) contents and bioconcentration potential of two Suillus mushrooms, and the probable dietary intake of this element from a mushroom meal. The determination of total Hg content of fungal and soil samples was performed using cold-vapour atomic absorption spectroscopy by a direct sample thermal decomposition coupled with gold wool trap of Hg and its further desorption and quantitative measurement at a wavelength of 253.7 nm. The median values of Hg contents (mg kg^?1 dry biomass) in 213 specimens of S. variegatus from 12 background areas varied widely from 0.087 to 0.51 for caps and from 0.041 to 0.24 for stipes. In 52 specimens of S. granulatus, the Hg contents ranged from 0.30 to 0.41 for caps and from 0.058 to 0.14 for stipes. Both species could be classified as moderate accumulators of Hg and the median bioconcentration factor values ranged from 7.0 to 14 (caps) and 2.1 to 13 (stipes) for S. variegatus and 9.5 (caps) and 1.3 (stipes) for S. granulatus. The estimated intake rates of Hg with the consumption of 300-g caps were from 0.0026 to 0.015 per capita or from 0.000037 to 0.00022 mg kg^?1 body mass and this do not indicate any cause for concern associated with eating a meal once or more in a week during the mushrooming season.     

Minimising transportation in manufacturing supply chains

The movement of raw material, work-parts and bought-out components is an essential aspect of modern-day global manufacturing systems. It is also an expensive, non-value adding and pollution-generating activity with many undesirable consequences. These manifest themselves not only in terms of the immediate cost of transportation between suppliers, manufacturers and customers but also in the consequential effect this movement has on human health and the environment. Accordingly, modern manufacturing supply chains should be designed with great care to minimise the amount of movement required both internally within a manufacturing facility's production system and externally between the supplier, manufacturer and customer. In so doing, a good supply chain design minimises the costs associated with the transportation of goods along with the effect this has on the environment. In complex supply chains, however, minimising overall transportation movement for large sets of components is no easy task. Consequently, the contribution contained in this paper seeks to outline a technique whereby an initial supply chain design solution which does so can be identified. The method is explained in the first instance via a straightforward material movement example. The resulting solution is subsequently modified to indicate its application in the context of temporal supply chain design. By utilising this approach, the article emphasises the importance of obtaining a solution that minimises transportation movement within the supply chain together with the practical effects of doing so on flexibility, cost and environmental pollution. In addition, the work required for further development of this technique is outlined and finally suitable conclusions are drawn.     

家庭食品处理风险行为特征与食源性疾病间相关性研究

借鉴国内外研究成果,结合中国实际界定了引发食源性疾病的家庭食品处理风险行为,并基于10省(区)2 163户家庭的横断面抽样调查数据,以实践理论为指导,运用因子分析和聚类分析方法,实证测度家庭食品处理风险行为特征。以食源性腹泻为研究病例,利用有序多分类Logit回归模型分析了家庭食品处理风险行为特征与食源性疾病之间的关系,确定家庭食品处理的关键风险行为特征与人群特征。结果表明,对应于食品处理安全行为,家庭食品处理风险行为特征主要为食品运输、食品冷藏与剩菜处理不当,厨房清洁用品交叉污染,生熟食品交叉污染,清洁卫生风险,烹调不彻底等七种类型,且生熟食品交叉污染与剩菜处理不当是引发家庭食源性腹泻的最主要风险行为特征,尤其是男性、已婚、年龄较大、家庭人口数较少、受教育程度和职业稳定度较低、以及个人和家庭年收入水平较低的家庭人群。家庭是预防食源性疾病的最后一道防线,政府应致力于与消费者进行风险沟通,提升消费者的责任认知,采用差异化策略改善风险消费者的家庭食品处理习惯,实施抗击食源性疾病战略。     

Can household consumers save the wild fish? Lessons from a sustainable seafood advisory

Conservation organizations seeking to reduce over-fishing and promote better fishing practices have increasingly turned to market-based mechanisms such as environmental sustainability labels (eco-labels) in order to shift patterns of household consumption. This paper presents an analysis of consumer response to an advisory for sustainable seafood adopted by a regional supermarket in the United States. The advisory consisted of a label in which one of three traffic light colors was placed on each fresh seafood product to inform consumers about its relative environmental sustainability. Green meant “best” choice, yellow meant “proceed with caution,” and red meant “worst choice”. Using a unique product-level panel scanner data set of weekly sales and taking advantage of the random phase-in of the advisory by the retailer, we apply a difference-in-differences identification strategy to estimate the effect of the advisory on overall seafood sales as well as the heterogeneous impact of the advisory by label color and whether the seafood met additional health-related criteria. We find evidence that the advisory led to a statistically significant 15.3% decline in overall seafood sales, a statistically significant 34.9% decline in the sale of yellow labeled seafood, and a statistically significant 41.3% decline in the sale of yellow labeled seafood on a mercury safe list. We find no statistically significant difference in sales of green or red labeled seafood.     

基于SPC理论的服务型导游管理模式构建

导游是旅游从业一线人员,代表着旅游业的形象,关系着旅游业的良性发展。在游客追求低廉出游价格时,导游因其弱势群体地位最终成为旅游服务利益方的牺牲品,导游生存、发展与管理已成为困扰旅游业的一大难题。SPC理论即服务利益链理论强调顾客与员工的让渡价值,认为企业盈利能力的增强主要源于顾客和员工的企业忠诚度并最终源于企业对内部员工的服务质量。基于SPC理论,探讨了我国服务型导游管理模式的构建,指出旅游服务各利益方应服务导游,创造导游良好的就业和发展环境,以解决导游管理难题。     

Residue behavior of etoxazole under field conditions in Egypt and estimation of processing factors during the production of strawberry juice and purée

Abstract

The degradation under field conditions and the residue behavior of etoxazole during juicing and purée making was evaluated. Etoxazole residues were determined by HPLC-UV at six different Pre Harvest Intervals (PHIs) as to estimate the degradation of residue in fruits. Samples with significant residues were processed and residue were determined after juicing and purée making. The effect of washing was also estimated. Processing Factors (PFs) for etoxazole after each step were less than 1 and the PFs of the overall processes were lower than 0.85 for washing fruits, 0.13 for juice and 0.04 for purée. The studied processes could obviously reduce the pesticide residues that are present in the raw strawberries. Uncertainties in the use of the PFs were identified due to the potential formation of metabolites during the processes.