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101.
长江原水臭氧-生物活性炭挂膜中试研究   总被引:1,自引:1,他引:0  
为了探究面向长江水源的臭氧-生物活性炭深度处理工艺的挂膜技术,进行了长江原水常州段的臭氧-生物活性炭挂膜中试研究.结果表明,在挂膜前期,由于炭柱的物理吸附作用逐渐饱和,炭柱对DOC(溶解性有机碳)、UV_(254)和COD_(Mn)(高锰酸盐指数)的去除率逐渐降低,对氨氮几乎没有去除,在挂膜中后期,由于活性炭上生物膜逐渐成熟,生物降解起主导作用,有机物和氨氮去除率升高并趋于稳定.90 d后,炭柱对DOC、UV_(254)和COD_(Mn)这3个有机物指标的去除率分别稳定在30.64%、57.50%和30.00%以上,氨氮去除率稳定在88.93%左右,认为挂膜成功.扫描电镜图显示活性炭表面出现丰富的菌胶团,同时高通量测序也验证了活性炭中丰富多样的微生物群落结构.  相似文献   
102.
In this paper, the dynamic relationship between global surface temperature (global warming) and global carbon dioxide emission (CO2) is modelled and analyzed by causality and spectral analysis in the time domain and frequency domain, respectively. Historical data of global CO2emission and global surface temperature anomalies over 129 years from 1860–1988 are used in this study. The causal relationship between the two phenomena is first examined using the Sim and Granger causality test in the time domain after the data series are filtered by ARIMA models. The Granger causal relationship is further scrutinized and confirmed by cross-spectral and multichannel spectral analysis in the frequency domain. The evidence found from both analyses proves that there is a positive causal relationship between the two variables. The time domain analysis suggests that Granger causality exists between global surface temperature and global CO2emission. Further, CO2emission causes the change in temperature. The conclusions are further confirmed by the frequency domain analysis, which indicates that the increase in CO2emission causes climate warming because a high coherence exists between the two variables. Furthermore, it is proved that climate changes happen after an increase in CO2emission, which confirms that the increase in CO2emission does cause global warming.  相似文献   
103.
104.
辽宁省区域经济差异与区域协调发展的初步研究   总被引:14,自引:0,他引:14  
本文利用辽宁省近年来的统计数据.通过对标准差、变异系数、离差、比率、相对发展速度等参数的计算。分析了辽宁省内各地区间的区域经济差异的总体特征和空间特征。并总结了产生区域差异的三个主要因素。即自然地理环境的差异(客观因素)、区域战略重点的转移(政策因素)以及各地区经济结构的差异。在此基础上.为辽宁省区域协调发展提出了对策与建议。  相似文献   
105.
沿海发达地区土地利用研究新进展与方向   总被引:7,自引:2,他引:5  
土地资源的短缺、质量退化与低效利用.已成为影响沿海发达地区生态安全与可持续发展的重要制约因素,也是土地利用管理与规划决策所面临的现实难题。我国沿海经济发达地区作为人地矛盾激化和经济快速转型背景下特殊的人文生态脆弱区,受到了包括地理学、生态学、经济学和社会学等多学科学者的密切关注,尤其是近10多年来在沿海土地利用变化及其效应研究方面取得了丰硕成果。主要以土地科学研究新方向和沿海地区经济社会发展态势为基本背景.从土地利用类型及其转换格局、驱动力因素辨识与驱动机制、土地利用转换的效应、区域土地可持续利用.以及土地利用优化配置与调控等方面,对沿海地区土地利用研究进行了初步梳理和评述,并指出今后应重视深化沿海发达地区土地利用研究的9个重点问题。  相似文献   
106.
采用灰色系统理论的关联度分析方法,研究了涪江上游骨滑坡的主要形成条件及触发因素。结果显示,相对主同差是滑坡的主要形成条件,地震是滑坡的主要触发因素,此外,还对滑坡相关因素进行了相关显著性比较,评价了每项相关因素的其中所起的作用,最后讨论了灰色系统理论的关联度分析方法在滑坡研究中的利弊。  相似文献   
107.
研究人口——经济系统,首先从人口系统着手,并分别对各子系统进行分析和综合。对人口系统的研究着重于控制数量、强调人口素质,尤其是要求人口文化素质对科学技术转化生产力能够起到保证作用,其最终目的是促进社会经济的发展。  相似文献   
108.
PROBLEM: Most investigations of injuries among Chinese populations are focused on urban or better developed areas, fewer on rural or poor areas. METHODS: From September 21 to 27, 2002, an epidemiological investigation of eight kinds of injury-related events was carried out among 1,944 students in 39 classes randomly sampled from middle schools in Lijin County, a rural area. The eight kinds of events were: (a) traffic accidents, (b) poisoning, (c) fall, (d) burn or scald, (e) blunt or sharp tools contact, (f) electrical contact, (g) animal or insect bites, and (h) non-fatal drowning. RESULTS: The total incidence rate of eight kinds of injuries in the previous year was 21.1%. The incidence rate among boys was 24.2%, while that among girls was 17.4%, which was significant (chi-square=13.4, P<0.05). The incidence rate among junior high school students was 23.1%, while that among senior high school students was 15.5%, which was also significant (chi-square=13.2, P<0.05). A case-control study of 410 students with at least one of eight kinds of injury events indicated that students' gender and their mothers' health status were related to their injuries. CONCLUSION: The injury incidence rate in a rural area was less than other results in urban or developed areas. Students' gender and mothers' health status were important factors associated with the occurrence of injury. IMPACT ON INDUSTRY: In order to improve the surroundings of the growing population of adolescents, some preventive measures should be put forward, especially to the high-risk students of injury.  相似文献   
109.
中美两国经济发展与铜消费量对比研究   总被引:4,自引:0,他引:4  
发达国家的发展过程表明,经济增长与铜消费量密切相关。本文由IPAT方程推导了铜消费指标与GDP间的关系式,得出GDP的年增长率(g)的单位GDP铜消费量的年下降率(t)是影响铜消费量变化的两个重要参数。给出了中、美两国铜消费指标与GDP间的关系曲线;中国1960-2004年间单位GDP的铜消费量并未形成明显的上升或下降趋势;美国1941-2004年间单位GDP铜消费量的变化总体上逐年降低,1941年为17.80kg/10^4USD,2003年为2.56kg/10^4USD,单位GDP的铜消费量降低近7倍。对应不同的单位GDP铜消费量年下降率的假设,估计了未来25年内中国经济增长与铜消费指标间的关系以及单位GDP铜消费量降低的倍数。  相似文献   
110.
Recent debates regarding the criteria for evaluating occupational health and safety interventions have focused on the need for incorporating qualitative elements and process evaluation, in addition to attempting to live up to the Cochrane criteria. Reflecting fundamental epistemological conflicts and shortcomings of the Cochrane criteria in evaluating intervention studies, the debate challenges the traditional (quasi-) experimental design and methodology, which are often used within safety research. This article discusses a revised ‘realistic evaluation’ approach as a way to meet these challenges.Evidence from the literature as well as examples from an integrated (leader-based/worker-based) safety intervention study (2008-2010) in a large wood manufacturing company are presented, with focus on the pros and cons of using randomised-controlled-trials and a revised realistic evaluation model.A revised realistic evaluation model is provided which includes factors such as role behaviour, leader and worker motivation, underreporting of accidents/injuries, production pressure, unplanned organisational change and accounting for multilayer effects. These can be attained through qualitative and/or quantitative methods, allowing for the use of realistic evaluation in both large and small scale studies, as well as in systematic reviews. The revised realistic evaluation model offers a promising new way of designing and evaluating occupational safety research. This model can help safety science move forward in setting qualitative and/or quantitative criteria regarding context, mechanisms and processes for single studies and for reviews. Focus is not limited to whether the expected results appear or not, but include suggestions for what works for whom, under what circumstances, in what respects and how.  相似文献   
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