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1.
高原环境条件及其对机电产品的影响 总被引:8,自引:0,他引:8
介绍我国高海拔环境条件,包拓气压,气温,太阳辐射等并有环境参数值,同时介绍高原环境条件对机电产品的影响,而主要是低气压对机机械设备的影响等。 相似文献
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综述了各种因素对镁合金大气腐蚀的影响,其中介绍了单一因素NaCl及两种因素协同作用对镁合金大气腐蚀的影响。同时介绍了镁合金大气电偶腐蚀的影响因素与Al含量对镁合金大气腐蚀的影响。简述了研究镁合金大气腐蚀的几种常用表征手段。 相似文献
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煤矸石对环境的影响及其防治对策分析 总被引:2,自引:0,他引:2
分析介绍了煤炭开采过程中产生的煤矸石对生态环境造成的不利影响,为保护矿区环境,减少煤矸石对环境的污染,将煤矸石变废为宝,重点介绍了利用煤矸石发电等减少污染的经验. 相似文献
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介绍了航空机载产品磁影响测量标准的技术要求和测量方法,深入剖析了磁影响测量的原理,澄清了标准中容易混淆的磁影响限值的确定原则,详细解释了磁强计测量磁影响的方法,经过实践检验,这种磁强计测量航空机载产品磁影响的方法准确可靠。 相似文献
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环境是影响产品可靠性指标中首要因素,而对电子产品影响最大的环境因素是高温。高温环境下首先会使得电子产品的温升值达到更高的水平,从而使得产品在更短的时间内出现故障,进而寿命终结。而任何电子产品要保证在其规定的高温条件下可以正常使用,都需要进行相应的高温环境试验,确定产品在高温环境下贮存和使用的适用性。本文首先介绍高温环境对产品的影响以及会引发何种失效模式;随后介绍为保证产品在高温环境下符合应用而制定的相应标准以及标准中规定的测试项目及指标要求;同时,介绍为保证产品高温符合性而一般采取的设计方法。通过对高温环境的影响分析、标准要求及一般的设计方法,为产品高温环境的适用性及及测试提供参考。 相似文献
10.
介绍了污水处理厂臭气的处理方法,重点介绍了生物过滤除臭工艺及影响因素,提出生物过滤法处理污水处理站(厂)臭气是今后的发展方向。 相似文献
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本电子设备安全性设计的目的就是通过识别、分析、评价系统中存在的危险性,预计事故对人员、设备和环境的破坏的可能性和严重性,根据其结果调整工艺、设备、操作、管理、生产周期和投资等因素,提出消除、减少、控制危险及危险事件的措施,以便使事故在发生之前得到控制,降低系统运行的风险。 相似文献
12.
The Akaki River, laden with untreated wastes from domestic, industrial, and commercial sources, serves as a source of water
for irrigating vegetable farms. The purpose of this study is to identify the impact of waste-water irrigation on the level
of heavy metals and to predict their potential mobility and bioavailability. Zn and V had the highest, whereas Hg the lowest,
concentrations observed in the soils. The average contents of As, Co, Cr, Cu, Ni, Zn, V, and Hg of both soils; and Pb and
Se from Fluvisol surpassed the mean + 2 SD of the corresponding levels reported for their uncontaminated counterparts. Apparently,
irrigation with waste water for the last few decades has contributed to the observed higher concentrations of the above elements
in the study soils (Vertisol and Fluvisol) when compared to uncontaminated Vertisol and Fluvisol. On the other hand, Vertisol
accommodated comparatively higher average levels of Cr, Cu, Ni, Zn, etc V, and Cd, whereas high contents of Pb and Se were
observed in Fluvisol. Alternatively, comparable levels of Co and Hg were found in either soil. Except for Ni, Cr, and Cd in
contaminated Vertisol, heavy metals in the soils were not significantly affected by the depth (0–20 and 30–50 cm). When the
same element from the two soils was compared, the levels of Cr, Cu, Ni, Pb, Se, Zn, V, Cd at 0–20 cm; and Cr, Ni, Cu, Cd,
and Zn at 30–50 cm were significantly different. Organic carbon (in both soils), CEC (Fluvisol), and clay (Vertisol) exhibited
significant positive correspondences with the total heavy metal levels. Conversely, Se and Hg contents revealed perceptible
associations with carbonate and pH. The exchangeable fraction was dominated by Hg and Cd, whereas the carbonate fraction was
abounded with Cd, Pb, and Co. conversely, V and Pb displayed strong affinity to reducible fraction, where as Cr, Cu, Zn, and
Ni dominated the oxidizable fraction. Cr, Hg, Se, and Zn (in both soils) showed preference to the residual fraction. Generally,
a considerable proportion of the total levels of many of the heavy metals resided in non residual fractions. The enhanced
lability is generally expected to follow the order: Cd > Co > Pb > Cu > Ni > Se > V and Pb > Cd > Co > Cu > Ni > Zn in Vertisol
and Fluvisol, respectively. For the similar wastewater application, the soil variables influence the status and the distribution
of the associated heavy metals among the different soil fractions in the study soils. Among heavy metals that presented relatively
elevated levels and with potential mobility, Co, Cu, Ni (either soil), V (Vertisol), Pb, and Zn (Fluvisol) could pose health
threat through their introduction into the food chain in the wastewater irrigated soils. 相似文献
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This assessment of the environmental protection regulatory system for the $2.2 billion iron and steel plant, oil refinery, and thermal generating station composing the core of the greenfield Nanticoke industrial complex is based upon: the use of governmental and industrial research in project management; technology and institutional arrangements for environmental protection; evidence of environmental changes to date; analysis of government and industrial approval files; and interviews with government, industry, and interest group representatives. Planning, regulation, and management have been reasonably efficient and effective to the beginning of the operational stage for all three major industries as of spring 1980. Of major future concern, however, is management of the cumulative and synergistic impacts of the industries and associated development on air quality as well as the lands, waters, and sensitive ecosystems of the nearby Lake Erie coast. Continuous monitoring, more comprehensive research, and better overall coordination of government, industrial, and public interests are required if Nanticoke benefits are to be achieved without undue cost to pre-project resource users within and outside the Haldimand-Norfolk region. 相似文献
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Of Bodies, Place, and Culture: Re-Situating Local Food 总被引:1,自引:0,他引:1
Laura B. Delind 《Journal of Agricultural and Environmental Ethics》2006,19(2):121-146
In the US, an increasingly popular local food movement is propelled along by structural arguments that highlight the inequity
and unsustainablity of the current agri-food system and by individually based arguments that highlight personal health and
well-being. Despite clear differences in their foci, the deeper values contained in each argument tend to be neglected or
lost, while local innovations assume instrumental and largely market-based forms. By narrowing their focus to the rational
and the economic, movement activists tend to overlook (or marginalize) the role of the sensual, the emotional, the expressive
for maintaining layered sets of embodied relationships to food and to place. This paper seeks to show that cultural and nonrational
elements are fundamental to local food discussions. It proceeds from the assumption that, without them as full partners, the
movement cannot be sustained in any felt, practiced, or committed way. To this end, it discusses the concept of place and
bodies in place, as well as the connections between the ecological and the cultural, the sensual and the scientific. It offers
a new set of questions and conceptual tools with which advocates and activists may “ground,” and thereby revalue and restore,
the promise and practice of local food. 相似文献
15.
党政办公室在高校的发展与建设中承担着组织、协调、服务、督办等重要的职能与作用.面对新形势、新任务、新要求,党政办公室要跟上时代的步伐,就必须不断开拓进取,建立一种新的、现代的、更加先进的工作理念、工作方式、工作机制,充分调动工作人员的创造性和积极性,提高高校党政办公室工作的效率,建设一流部门,争创一流业绩. 相似文献
16.
气候变化问题是人类社会共同面临的重大挑战,关系到人类生存和各国利益。推进碳达峰碳中和是中国的一项重大战略决策,是负责任大国对国际社会的庄严承诺,也是推动高质量发展的内在要求。本文归纳分析欧盟、美国、日本、韩国、德国、英国等主要发达经济体碳达峰的经济社会特征、碳中和的路径共识,系统梳理推动实现碳达峰碳中和的经验举措,对比分析中国国内进展和差距,并提出重点借鉴的国际经验与启示。研究发现,中国已经逐步具备实现碳达峰国家的基本特征,但相比发达国家,在降碳效果核算评估、低碳安全高效能源系统构建、碳价格传导机制设计、低碳技术创新和新业态模式打造、法规制度系统化构建等方面仍有差距,仍需加强政策驱动和重点国际经验借鉴,进一步优化“双碳”目标评估指标体系,将构建清洁、低碳、安全、高效能源系统作为能源生产和消费革命的主要目标,有序推进碳排放权交易市场建设和能源资源市场化价格调控,强化绿色低碳技术的研发创新,加快构建形成系统性推动“双碳”目标的法规体系。 相似文献
17.
Adel Ahmed Mohamed Abdel-Aleem Marzooka Shaban Abdel-Tawab Mohamed El-Kassem M. Hassouna 《环境质量管理》2023,32(4):119-135
Natural, acid and base modified kaolin clays were studied for the sake of phenol and 4-chlorophenol removal from aqueous environments and their application to real ground and industrial wastewater samples. Scanning electron microscope (SEM), infrared spectroscopy (IR), X-ray diffraction (XRD), Thermo Gravimetric Analysis (TGA), Differential Thermal Analysis (DTA), and Surface area analysis were employed for characterization of the adsorbents microstructure. Operating factors such as adsorbent dose, solution pH, initial phenol concentration, and contact time were studied. The experimental data displayed that the increase of the adsorbent dose, contact time, and pH value from 2 to 7 increases the efficiency of the removal process. Optimal conditions for phenolic removal were; contact time of 300 min, primary phenol solution of 25 mg/L, pH 7 and 2.5 g/L as an appropriate adsorbent dose using crude (natural), acid modified and base modified kaolin clays. The higher phenolic removal efficiencies were obtained at 5 mg/L as 90, 97, 96.2%, respectively, for the adsorbents in the previously mentioned order. The adsorption capacity in the removal of phenol and 4-chlorophenol were 7.481 and 4.195, 8.2942 and 3.211, and 8.05185 and 18.565 mg/g, respectively, for the adsorbents in the same mentioned order. The adsorption equilibrium data were fitted and analyzed with four isotherm models, namely, Langmuir, Freundlich, Temkin, and Dubinin–Radushkevich isotherm equations. The adsorption process of phenol on studied adsorbents was exothermic, spontaneous and thermodynamically favorable proved by the negative values of their thermodynamic parameters ΔH° and ΔG°. The correlation coefficient (R2) for all concentrations was higher than 0.94, which indicates that in the studied system, the data suitably fit the first-order kinetics. The % desorption capacity was amounted to 96%, 91.11%, and 87.06% of adsorbed phenol, respectively, for the adsorbents in the previous order using 0.1N NaOH and 10% V/V ethanol solutions as eluents at 25°C, indicating the reusability of the adsorbents. Kaolin and its modified forms can be introduced as eco-friendly and low-cost adsorbents in water remediation implementation. 相似文献
18.
Teresa Fidélis Teresa Carvalho 《Journal of Environmental Planning and Management》2015,58(7):1173-1195
Estuarine areas often concentrate complex and conflicting sets of natural, economic and social resources and activities with multiple challenges to planning and management approaches as well as to governance practices. Using a set of integration factors depicted from the literature review, the paper analyzes the main features of the new set of the Portuguese estuary types of plans and assesses their potential added value, while focusing the analysis on the estuary of the Vouga River (Ria de Aveiro). The results are twofold. On the one side, their uniqueness, by treating the estuary as a planning unit, integrating the water resources and the land use planning systems and by establishing mandatory rules for the estuary uses, embodies relevant potential for reducing boundary tensions and to improve integrative approaches. On the other side, while at the level of plan content the contribution of the Portuguese Estuary Land Use and Management Plans (Planos de Ordenamento de Estuário) legislation brings strong new prospects for integration, at the level of planning process and implementation, further efforts should be undertaken. Their added value, especially in complex institutional and societal estuarine contexts, such as the Ria de Aveiro, strongly depends on more robust participation schemes through which knowledge, institutions, aims and measures are articulated in a collective vision and shared governance process. 相似文献
19.
B. De Martis M. A. de Miranda Restivo A. Mocci Demartis E. Serra 《Environmental management》1992,16(3):381-388
Capoterra Pond in southern Sardinia is described and analyzed with respect to its morphological, meteorological, physical
and chemical characteristics, and its zoobenthic, zooplankton, and phytoplankton biocenoses. The birdlife, flora, and riparian
associations of vegetation are studied in order to draw international attention to the importance of this lagoon, the precariousness
of its ecosystem, the seriousness of current attempts to destabilize it, and the need to encourage the Sardinian authorities
to initiate conservation measures, especially as rare birds have found their niches there. 相似文献
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Anne-Lucie Raoult-Wack Nicolas Bricas 《Journal of Agricultural and Environmental Ethics》2002,15(3):323-334
After a century of major technicaladvance, essentially achieved by and for theindustrialized countries, the evolution of thefood sector in southern countries should nolonger be thought of in terms of a ``headlongpursuit.'' In the present context of demographicgrowth, urbanization, poverty and disparities,environmental degradation, and globalization oftrade, new priorities have emerged, and newethical questions have been raised, mainlyrelated to sustainability and equity. Thispaper analyses these ethical concerns in thefollowing terms: can the model of food sectordevelopment initiated by the industrializedcountries be applied to the entire world on asustainable and equitable basis, given theeffects of this development with regard to theenergy consumed, the changes in dietarybehavior and related nutritional problems, thenew demands in terms of food safety, thequestions of biodiversity, ownership ofknowledge, cultural identities, gender issues,and Man's relationship to food and Nature? 相似文献