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821.
采用悬浮填料 SBR工艺处理青霉素制药废水 ,结果表明 :青霉素废水中含有的抗生素对微生物有抑制作用 ,宜采用非限制曝气的进水方式 ;最佳运行工艺为一周期 8h ,非限制曝气进水 1h ,反应 5h ,沉淀、排水和闲置 2h ;该工艺与单一SBR工艺相比 ,可提高CODCr去除率 2 0 %以上 ,缩短反应时间 2h ;且具有良好的稳定性 ,当进水CODCr浓度变化较大( 80 0— 2 5 0 0mg L)时 ,CODCr去除率一直稳定于 83 %— 85 %之间 ,出水CODCr在 136— 35 0mg L之间 ,达到国家二级排放标准。  相似文献   
822.
环境监理计算机管理信息系统的软件规划   总被引:1,自引:1,他引:1  
在对各种环保监理工作调研的基础上,了解环境监理机构的主要职责,并对软件的功能模块进行划分为软件的开发和编程提供了技术及工作总线。  相似文献   
823.
《Ecological modelling》2003,170(2-3):453
In this paper, we address three aspects of the brown bear population in Slovenia: its size (and its evolution over time), its spatial expansion out of the core area, and its potential habitat based on natural habitat suitability. Data collected through measurement/observation of the bear population and from the literature are used. A model is developed for each aspect. The results are estimates of population size, a picture of the spatial expansion of the population and maps of its optimal and maximal potential habitat (based on natural suitability). Overall, the brown bear population has been increasing since the establishment of a core protective area and has been expanding outside this area. The habitat suitability maps show that there is room for further expansion. Based on habitat suitability and bear population density, as well as human activity and current damage reports, we recommend that the Alps should be temporarily kept free of the bears, until the necessary mitigation measures regarding human–bear conflicts are carried out. On the other hand it is of crucial importance to adapt human activities and improve bear management in the optimal habitat, with which the goals of successful conservation of the species might be achieved.  相似文献   
824.
烟粉虱成虫的昼夜时空动态及空间格局   总被引:11,自引:0,他引:11  
观察了 1d内西葫芦(Cucurbitapepo)植株上烟粉虱成虫数的变化,以早晨 6点最高,中午 12点达到最低点.经统计分析得到 2003年和 2004年 1d内西葫芦单株虫量与气温、空气相对湿度和温湿度系数的相关系数.对两年的观察结果进行卡方适合性检验, 2003年和 2004年,烟粉虱成虫昼夜在植株上的种群波动趋势一致 (χ2 =0. 82 <χ20. 05, 7 ).空中捕虫试验结果为早晨 6点捕虫量最低,上午 10点捕虫量最高.空中捕虫量与光照强度的相关程度最高,与气温的相关程度次之.阴天空中捕虫量极低.还观察到烟粉虱成虫在早晨、夜间、阴天和雨日多停留在植株的叶背,其反应迟钝、活动能力较差.对烟粉虱成虫空间格局频次分布检验结果显示,所有调查田块的害虫空间格局一致,均属于负二项分布; 6项分布型指数测定结果,烟粉虱成虫在田间皆为聚集分布,其聚集的原因可能系物种本身的聚集行为所致. 图 3表 3参 10  相似文献   
825.
This paper concludes the publication of theJournal of Coastal Conservation from 1995–2004 after the European Coastal Union and the Publishers decided to terminate the production of the journal. We look back at the 206 research papers published in this period while concentrating on Geographical and ecological variation, Focuses and trends, and Progress in European coastal conservation and management. Three indices are added: (1) a list of the 206 papers; (2) an Author Index; and (3) a Subject Index based on the titles, keywords and some additional important subjects found in the tables and figures.  相似文献   
826.
Decision making in dune management: theory and practice   总被引:1,自引:0,他引:1  
Effective decision making depends upon the availability of quality information. Procedures involved in assessing dune vulnerability and protection require monitoring of sporadic processes and information must be collected from many discipline sources. In particular, a significant challenge to strategic management is recognition of subtle discontinuities which could undermine the long term stability of the dune system. These changes may be irregular and/or non linear requiring managers to be aware of existing parameters, patterns and emerging discontinuities. A range of components within the system should be measured on a systematic, temporal and spatial basis. An environmentalchecklist is a useful management technique which systematises information, so that strategic objectives can be made operational and achievable. Problems can be identified and solved with this methodology particularly if it is incorporated into aW problem solving model. The checklist procedure proposed in this paper has been developed and tested in field conditions for a range of north-west and south-European dune systems. Whereas a universalchecklist applicable to all systems is utopian in aim, intra and extra-regional comparisons can be undertaken with only minor modifications of some components. Parameters covering site and dune morphology, beach condition; surface character of the seaward 200 m of the dunes; pressure of use and recent protection measures are the basis for calculating vulnerability and protection indices. The balance between these indices can be determined, analysed and form the foundation for future informed management decisions.  相似文献   
827.
以MODIS遥感影像数据为数据源,应用遥感和GIS技术对泾河流域植被覆盖格局进行分析。结果表明:(1)泾河流域植被覆盖类型以退化草地和草地为主,二者占流域总面积的53.30%;地面覆盖程度较高的森林、疏林仅占流域总面积的9.83%,流域植被覆盖程度较低。(2)受自然环境条件和人类活动的影响,退化草地、稀疏灌丛、郁闭灌丛和疏林破碎化程度较为严重,对地面覆盖程度最低的退化草地除集中分布于流域北部外,主要零散分布于流域中、南部,其斑块形状复杂多样,数量最多,应成为流域植被恢复的重点。(3)各植被覆盖类型的斑快数量组成以小斑块所占比例最大,最小斑块比率均在50.0%以上;森林的斑块面积多样性最大,草地的斑块面积多样性最小。  相似文献   
828.
本文介绍了一个用BASIC语言编写的微机程序,即CDI程序。该程序是根据最小二乘修正加上外推的原理编制的,用于粉末衍射数据的晶胞参数计算和粉末图指标化。CDI程序可以处理所有晶系的衍射数据并得出令人满意的计算结果。程序已在IBMPC/XT,长城0520CH及C.S.重型微机上运行了好几年并解决了一系列实际问题。  相似文献   
829.
Introduction: The construction industry in Malaysia has been bedevilled by myriads of risk issues that have hampered its smooth operations in recent times. This paper is an empirical assessment that aims to examine the effect of coercive pressure on the relationship between organizational structure and construction risk management among construction industry in Malaysia. Method: Based on the proposed model, a quantitative method was employed to obtain data from G7 construction industry operating within the peninsular Malaysia. Out of the 180 copies of questionnaire, 165 copies were properly filled, returned, and used for the analysis. PLS-SEM was used to analyze the obtained data. Results: The findings of the study affirmed that specialization, centralization, and management of risk by the construction industry had positive correlation. Conclusions: As anticipated, coercive pressure had positive moderating correlation with both formalization and the management of risk by the construction industry. Similarly, it was also found that in the course of carrying out construction activities, coercive pressure made significant interactive influence on formalization, specialization, and centralization. Practical Applications: Coercive pressure reduced the frequency of accidents among workers in the process of carrying out construction works.  相似文献   
830.
为保障作业人员身心健康和作业效率,运用E-Prime软件模拟认知性VDT持续作业,通过方差分析提出作业疲劳综合评价指标体系,并使用客观绩效指标和生理指标作为输入变量,主观疲劳综合指数作为输出变量,训练BP神经网络,对作业疲劳进行模式识别;提出认知性VDT持续作业工间休息机制。结果表明:通过正确反应时间、注视时间、瞳孔直径、眨眼频率4项指标,对VDT持续作业疲劳进行模式识别的结果可信度较高。因此,基于上述4项指标提出的工间休息机制客观有效。  相似文献   
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