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61.
由于我国乡镇经济的迅速发展以及乡镇村民生活水平加速提高,乡镇的垃圾种类及数量趋向于城市.乡镇村民居住较为分散,垃圾分类、收集、循环利用相较于城市困难,因此推进乡镇垃圾分类循环利用迫在眉睫.本文从闽侯县上街镇展开调查,以乡镇垃圾分类、回收循环利用为关键词展开分析,并从上街镇垃圾分类循环利用模式存在的问题进行分析、总结和建... 相似文献
62.
In this paper, wind energy potential of four locations in Xinjiang region is assessed. The Weibull distribution as well as the Logistic and the Lognormal distributions are applied to describe the distributions of the wind speed at different heights. In determining the parameters in the Weibull distribution, four intelligent parameter optimization approaches including the differential evolutionary, the particle swarm optimization, and two other approaches derived from these two algorithms and combined advantages of these two approaches are employed. Then the optimal distribution is chosen through the Chi-square error (CSE), the Kolmogorov–Smirnov test error (KSE), and the root mean square error (RMSE) criteria. However, it is found that the variation range of some criteria is quite large, thus these criteria are analyzed and evaluated both from the anomalous values and by the K-means clustering method. Anomaly observation results have shown that the CSE is the first one should be considered to be eliminated from the consequent optimal distribution function selection. This idea is further confirmed by the K-means clustering algorithm, by which the CSE is clustered into a different group with KSE and RMSE. Therefore, only the reserved two error evaluation criteria are utilized to evaluate the wind power potential. 相似文献
63.
污染天气分型研究对空气质量预报、污染源总量控制等具有重要的意义。基于2013年1月~2014年12月高空及地面天气形势划分了成都市的天气类型并探讨各天气类型下的空气质量状况及其污染天气特征,以期为空气质量预报和预警提供依据。结果表明,空气污染过程中,500 hpa环流形势主要有两槽一脊型、一槽一脊型、纬向型、槽脊同位相型等,其中两槽一脊型和槽脊同位相型控制下的空气质量最差。发生空气污染时,地面环流形势可分为高压型、高压后部型、高压底部型、低压型、低压顶部型、低压前部型、低压底部型、鞍型场型、冷锋前部型和均压场型,其中高压型、高压底部型、高压后部型控制下的空气质量最差。 相似文献
64.
In this study, we asked the Ariaal herders of northern Kenya to answer "why, what and how" they classified landscape, and assessed and monitored the biodiversity of 10 km(2) of grazing land. To answer the "why question" the herders classified grazing resources into 39 landscape patches grouped into six landscape types and classified soil as 'warm', 'intermediate' or 'cold' for the purpose of land use. For the "what question" the herders used soil conditions and vegetation characteristics to assess biodiversity. Plant species were described as 'increasers', 'decreasers' or 'stable'. The decreaser species were mostly grasses and forbs preferred for cattle and sheep grazing and the increasers were mostly woody species preferred by goats. The herders evaluated biodiversity in terms of key forage species and used absence or presence of the preferred species from individual landscapes for monitoring change in biodiversity. For the "how question" the herders used anthropogenic indicators concerned with livestock management for assessing landscape potential and suitability for grazing. The anthropogenic indicators were related to soils and biodiversity. The herders used plant species grazing preferences to determine the links between livestock production and biodiversity. By addressing these three questions, the study shows the value of incorporating the indigenous knowledge of herders into classification of landscape and assessment and monitoring of biodiversity in the grazing lands. We conclude that herder knowledge of biodiversity is related to the use as opposed to exclusive conservation practices. This type of knowledge is extremely valuable to conservation agencies for establishing a baseline for monitoring changes in biodiversity in the future. 相似文献
65.
文章介绍了上海郊区沼气开发利用的发展历程和现状,分析了上海沼气发展萎缩的原因,指出上海在节能减排的大形势、寻找合理的农村生活垃圾处理出路和解决小型禽畜养殖场的环境问题等压力下,对郊区的沼气发展产生了新的需求。而以小型养殖场为中心、吸纳农村有机生活垃圾的小型沼气系统则是上海郊区未来沼气发展的方向,也是新农村环境整治的可行途径。 相似文献
66.
传统开发区内,资源的流动是一些相互不发生关系的线性物质流的叠加,出入系统的物质流远远大于内部交互的物质流,因而造成经济活动的"高开采、低利用、高排放"特征,即"大量生产、大量消费和大量废弃"[1]。而发展循环经济,是我国贯彻落实科学发展观、建设资源节约型和环境友好型社会的重大战略选择[。2]目前新型开发区产业发展,则要求按照循环经济的理念,积极探索发展循环经济之路。本文以昌吉市高新技术产业开发区为例,研究其循环经济模式,为其他开发区设计和发展提供有益的经验和建议。 相似文献
67.
化学品危险性鉴别分类研究的现状与展望 总被引:4,自引:4,他引:0
从对GHS(化学品分类及标记全球协调制度)化学品危险性鉴别分类的分析出发,归纳和总结了联合国、欧盟、美国以及中国的化学品危险性鉴别分类研究现状;提出化学品危险性鉴别分类是获取化学品安全信息、评估化学品的固有危险性的重要手段;给出化学品危险性鉴别分类试验必须满足OECD(经济合作与发展组织)的各项标准和准则;对化学品危险性鉴别分类的应用前景及未来工作进行评述和展望;指出为化学品安全管理、事故应急救援、事故调查及做好基础数据的积累是今后研究工作的努力方向;提出了借鉴GHS,REACH(化学品注册、评估、许可和限制)等先进化学品安全监管法规,对完善我国的化学品安全监管制度,化学品鉴别分类标准的重要现实意义。 相似文献
68.
Fecal source tracking by antibiotic resistance analysis on a watershed exhibiting low resistance 总被引:2,自引:0,他引:2
The ongoing development of microbial source tracking has made it possible to identify contamination sources with varying accuracy,
depending on the method used. The purpose of this study was to test the efficiency of the antibiotic resistance analysis (ARA)
method under low resistance by tracking the fecal sources at Turkey Creek, Oklahoma exhibiting this condition. The resistance
patterns of 772 water-isolates, tested with nine antibiotics, were analyzed by discriminant analysis (DA) utilizing a five-source
library containing 2250 isolates. The library passed various representativeness tests; however, two of the pulled-sample tests
suggested insufficient sampling. The resubstitution test of the library individual sources showed significant isolate misclassification
with an average rate of correct classification (ARCC) of 58%. These misclassifications were explained by low antibiotic resistance
(Wilcoxon test P < 0.0001). Seasonal DA of stream E. coli isolates for the pooled sources human/livestock/deer indicated that in fall, the human source dominated (P < 0.0001) at a rate of 56%, and that human and livestock respective contributions in winter (35 and 39%), spring (43 and
40%), and summer (37 and 35%) were similar. Deer scored lower (17–28%) than human and livestock at every season. The DA was
revised using results from a misclassification analysis to provide a perspective of the effect caused by low antibiotic resistance
and a more realistic determination of the fecal source rates at Turkey Creek. The revision increased livestock rates by 13–14%
(0.04 ≤ P ≤ 0.06), and decreased human and deer by 6–7%. Negative misclassification into livestock was significant (0.04 ≤ P ≤ 0.06). Low antibiotic resistance showed the greatest effect in this category. 相似文献
69.
我国消防标准体系分析 总被引:6,自引:2,他引:4
为明确我国消防标准体系发展的方向和重点,分别从消防标准的数量、标龄、类型、属性和采标情况等5个方面对我国消防标准体系进行分析,并与国际标准化组织、欧盟标准化委员会和美国的消防标准体系进行了比较。研究结果表明:我国消防标准体系整体适用性在不断增强;需制定周期性标准复审计划;消防基础试验类和管理类标准应成为下一步消防标准制修订的重点;消防强制性标准所占比例有待进一步下调;需建立国际标准动态跟踪机制,同时应注重将我国先进的消防标准转化为国际标准。 相似文献
70.
沈立 《中国安全科学学报》2008,18(2):166-170
重大危险源及其监管越来越受到关注,历经十多年,重大危险源的表述及其基本定义并没有取得共识而完全统一,现在开始实施重大危险源申报登记制度,涉及重大危险源的辨识、评价、分级等大量的具体工作,相关的理论和方法应用比较复杂。笔者就有关问题提出了自己的看法,认为重大危险源分级不仅是一项技术方法,而且是一项政策性行为,标准的制定一定要紧密联系实际,有利推动安全生产工作。 相似文献