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101.
为准确评价尾矿库的安全等级,以黄金洞尾矿库为例,分析影响尾矿库安全的各因素之间的关系,综合运用模糊多元联系度理论与层次分析法(AHP),建立了包含5个影响因素和26个影响因子的尾矿库综合安全评价模型。由AHP得出各项主、客观指标的权重系数,引入模糊多元联系度理论,综合考虑确定性与不确定性因素,处理综合集成问题,构造隶属函数量化指标的实测值。结果表明:黄金洞尾矿库安全等级为Ⅱ级,尾矿库处于较稳定状态。经比较不确定性因素大小,得出尾矿排放(B3)>尾矿坝(B2)>安全管理(B1)>尾矿输送与回水(B5)>排洪系统(B4),说明尾矿排放指标的不确定性因素最大,需对尾矿排放加强管理。该模型得到的评价结果与实际结果相吻合,为尾矿库安全性评价提供了一种可行的方法。 相似文献
102.
《International Journal of Hydrogen Energy》2019,44(17):8904-8913
Hydrogen, producing electricity in fuel cells, is a versatile energy source, but with risks associated with flammability. Fuel cells use enclosures for protection which need ventilating to remove hydrogen emitted during normal operation or from supply system leaks. Passive ventilation, using buoyancy driven flow is preferred to mechanical systems. Performance depends upon vent design, size, shape, position and number. Vents are usually plain rectangular openings, but environmentally situated enclosures use louvres for protection. The effect of louvres on passive ventilation is not clear and has therefore been examined in this paper. Comparison ‘same opening area’ louvre and plain vent tests were undertaken using a 0.144 m3 enclosure with opposing upper and lower vents and helium leaking from a 4 mm nozzle on the base at rates from 1 to 10 lpm, simulating a hydrogen leak. Louvres increased stratified level helium concentrations by typically in excess of 15%. The empirical data obtained was also used in a validation exercise with a SolidWorks: Flow Simulation CFD model, which provided a good qualitative representation of flow behaviour and close empirical data correlations. 相似文献
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针对煤矿企业外包工程安全生产问题严重、事故多发的特点,通过对新的煤矿企业外包工程的安全管控模式研究,分析煤矿安全监管、技术和装备水平、安全培训等存在的问题,提出了实施煤矿外包工程队准入制度,创新外包安全管控模式,找到对外包工程安全状况进行管理的行之有效的办法。 相似文献
107.
Front-of-package labels (FOPL) are recommended to reduce consumer intake of ultra-processed food products (UPP). The multiple traffic-light label is one example of FOPL that indicates the content of target nutrients in products by displaying red (high), amber (medium), and/or green (low) color-coding. The red code may implicitly enhance sweetness perception and approach dispositions toward sweet UPP via cross-modal visual-taste interactions. We conducted two experiments to examine the possibility of contradictory influence of explicitly learned and implicit cross-modal associations on the emotional responses evoked by UPP pictures. In both experiments, we first explicitly associated the color codes with health-related meanings. In Experiment I (n = 78), a psychometric tool estimated the emotional responses (pleasantness and arousal ratings) evoked by UPP pictures when preceded by red, amber, or green color-codes. In Experiment II (n = 24), we recorded participants’ electrocortical brain activity to assess the early posterior negativity (EPN) component as an index of the emotional responses to UPP. The reported pleasantness (Experiment I) and the EPN amplitude (Experiment II) were greater for sweet UPP relative to salty UPP when primed with red codes but not when primed with green or amber. A red code increased positive emotions toward sweet UPP despite its explicit association with increased health-risks. Thus, the use of multiple traffic-lights might lead to an unintended implicit approach behavior toward sweet UPP. Designers, researchers, and policy makers may consider color-taste cross-modal associations when designing, testing, and applying FOPL. 相似文献
108.
Liesel Claeys Chiara Romano Karl De Ruyck Hayley Wilson Beatrice Fervers Michael Korenjak Jiri Zavadil Marc J. Gunter Sarah De Saeger Marthe De Boevre Inge Huybrechts 《Comprehensive Reviews in Food Science and Food Safety》2020,19(4):1449-1464
In recent years, there has been an increasing interest in investigating the carcinogenicity of mycotoxins in humans. This systematic review aims to provide an overview of data linking exposure to different mycotoxins with human cancer risk. Publications (2019 and earlier) of case–control or longitudinal cohort studies were identified in PubMed and EMBASE. These articles were then screened by independent reviewers and their quality was assessed according to the Newcastle–Ottawa scale. Animal, cross‐sectional, and molecular studies satisfied criteria for exclusion. In total, 14 articles were included: 13 case–control studies and 1 longitudinal cohort study. Included articles focused on associations of mycotoxin exposure with primary liver, breast, and cervical cancer. Overall, a positive association between the consumption of aflatoxin‐contaminated foods and primary liver cancer risk was verified. Two case–control studies in Africa investigated the relationship between zearalenone and its metabolites and breast cancer risk, though conflicting results were reported. Two case–control studies investigated the association between hepatocellular carcinoma and fumonisin B1 exposure, but no significant associations were observed. This systematic review incorporates several clear observations of dose‐dependent associations between aflatoxins and liver cancer risk, in keeping with IARC Monograph conclusions. Only few human epidemiological studies investigated the associations between mycotoxin exposures and cancer risk. To close this gap, more in‐depth research is needed to unravel evidence for other common mycotoxins, such as deoxynivalenol and ochratoxin A. The link between mycotoxin exposures and cancer risk has mainly been established in experimental studies, and needs to be confirmed in human epidemiological studies to support the evidence‐based public health strategies. 相似文献
109.
Bingren Tian Dong Xiao Tingting Hei Rui Ping Shiyao Hua Jiayue Liu 《Polymer International》2020,69(7):597-603
Cyclodextrin is an odorless and tasteless cyclic oligosaccharide widely used in various fields such as food, medicine and the environment. Cyclodextrin can improve solubility and stability, and can mask the bad taste of specific substances. Cyclodextrins and their polymers primarily act by forming complexes in foods, and can be applied in food packing, food analysis, enhancing the properties of antioxidants, antibacterials, for stability and so on. The challenges and opportunities facing this area are reviewed. It is hoped that the review will provide useful information for future applications of cyclodextrin in the food industry. © 2020 Society of Chemical Industry 相似文献
110.
Shoue Chen Sandrayee Brahma Jonathon Mackay Changyong Cao Bahar Aliakbarian 《Journal of food science》2020,85(3):517-525
Food supply chain is a rapidly growing integrated sector and covers all the aspects from farm to fork, including manufacturing, packaging, distribution, storing, as well as further processing or cooking for consumption. Along this chain, smart packaging could impact the quality, safety, and sustainability of food. Packaging systems have evolved to be smarter with integration of emerging electronics and wireless communication and cloud data solutions. Although there are many factors causing the loss and waste issues for foods throughout the whole supply chain of food and there have been several articles showing the recent advances and breakthroughs in developing smart packaging systems, this review integrates these conceptual frameworks and technological applications and focuses on how innovative smart packaging solutions are beneficial to the overall quality and safety of food supply by enhancing product traceability and reducing the amount of food loss and waste. We start by introducing the concept of the management for the integrated food supply chain, which is critical in tactical and operational components that can enhance product traceability within the entire chain. Then we highlight the impact of smart packaging in reducing food loss and waste. We summarize the basic information of the common printing techniques for smart packaging system (sensor and indicator). Then, we discuss the potential challenges in the manufacturing and deployment of smart packaging systems, as well as their cost-related drawbacks and further steps in food supply chain. 相似文献