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81.
Summary To solve environmental problems a vast amount of manpower, material and financial resources has been spent. Some people consider that this is necessary, and a reasonable price which human beings must pay for development, especially industrialisation. Maybe it is true. But can people solve the environmental problems of developing countries better when they have learned the experiences and lessons of developed countries? One possible way is proposed in this paper, which makes a special reference to the real situation in China. The fundamental idea is to develop and apply appropriate technologies in the phase of national industrialisation. This will help developing countries to achieve desired environmental effects more economically. The appropriate technologies mentioned in the paper are of two kinds: appropriate industrial production technologies and appropriate environmental technologies. The development of the former will help to reduce environmental pollution and other problems caused by industrialisation. The development of the latter will enable developing countries to keep an acceptable environmental quality within a controlled cost. In the paper the definition of appropriate technologies is clarified, and the criteria for the selection and evaluation of appropriate technologies are proposed. The possibility of a realisation of developing the economy and protecting the environment at same time is then analysed. The conclusion is that development and application of appropriate technologies is an optimal strategy when the real conditions of developing countries like China are considered. Finally, some of the initial appropriate environmental technologies which should be developed are suggested.Professor Ranjie Hou has recently been working as a Research Fellow at the Alexander von Humboldt Foundation in Karlsrube University, Federal Republic of Germany.  相似文献   
82.
均压防灭火定量分析技术研究及其应用   总被引:4,自引:0,他引:4  
均压是防治煤矿自然发火的主要措施之一。针对均压应用中的定性分析方法及两点式均压方法的不足,提出了均压防灭火定量分析技术并开发了与采空区相连两个工作面间均压的计算机摸拟计算程序。阐述了程序均压原理、内容及应用实例。这项技术具有创新性和应用推广价值,可以提高均压防灭火技术应用的经济性和安全性  相似文献   
83.
Research on community characteristics of riparian herbs is an important scientific basis of riparian vegetation rehabilitation. This study aimed to investigate the species diversity and quantitative characteristics of riparian herbs in Liaohe River Conservation Area and its tributaries. Herbaceous communities were investigated by sample line method. Group average clustering analysis and detrended correspondence analysis (DCA) were used to find the major environmental factors affecting the distribution pattern of riparian herbaceous communities. The result showed altogether 154 herbaceous species, belonging to 40 families and 96 genera. The riparian herbaceous species diversity was found to be correlated to river slope, sinuosity and stream order, being lower in rivers of mountain area than in rivers of plain area, and higher in tributaries than in Liaohe River Conservation Area. Clustering analysis classified the herbaceous communities into 23 types, being dominated by hygrophytes including communities of Echinochloa crusgalli, Oenanthe javanica, Polygonum hydropiper, Murdannia keisak, Artemisia selengensis, Scirpus triqueter, Heleocharis soloniensis, Pycreus sanguinolentus, Cyperus fuscus, Phragmites australis, Polygonum amphibium, Carex diandra + Artemisia selengensis and Carex diandra + Rorippa islandica. Correlation analysis between DCA ordination axes and environmental factors showed that the altitude, river slope, sinuosity and stream level were the major environmental factors affecting the distribution pattern of herbaceous communities in the riparian zone of Liaohe River Conservation Area and its tributaries. The results of CCA showed that the contribution ratio of stream level was the highest, followed by altitude and slope, with sinuosity the last. The results suggested that riparian herbaceous characteristics are affected by the comprehensive force of altitude, river slope, sinuosity and stream order, and that Calamagrostis epigeios, Triarrhena sacchariflora and Phragmites australis are suitable species for riparian vegetation rehabilitation.  相似文献   
84.
Fly ash is a hazardous byproduct of municipal solid wastes incineration (MSWI). An alkali activated blast furnace slag-based cementitious material was used to stabilize/solidify the fly ash at experimental level. The characteristics of the stabilized/solidified fly ash, including metal leachability, mineralogical characteristics and the distributions of metals in matrices, were tested by toxic characteristic leaching procedure (TCLP), X-ray diffraction (XRD) and scanning electron microscopy-energy dispersive spectrometer (SEM-EDS) respectively. Continuous acid extraction was utilized to extract metal ions and characterize their leaching behavior. The stabilization/solidification procedure for MSWI fly ash demonstrates a strong fixing capacity for the metals by the formation of C-S-H phase, hydrated calcium aluminosilicate and ettringite. The stabilized/solidified fly ash shows a dense and homogeneous microstructure. Cr is mainly solidified in hydrated calcium aluminosilicate, C-S-H and ettringite phase through physical encapsulation, precipitation, adsorption or substitution mechanisms, and Pb is mainly solidified in C-S-H phase and absorbed in the Si-O structure.  相似文献   
85.
复合菌种协同发酵酒糟生产饲料蛋白研究   总被引:6,自引:0,他引:6  
以笔者选育的8503和8505复合菌种为试验菌,以白酒糟为原料,经最适试验,确定最优条件为:培养温度30.0℃,初始PH5.5,(NH4)2SO4添加量为5mg/ml,投料量10%,接种量5-10%,发酵期限5d,在最适条件试验的基础上,进行了5L发酵罐试验,发酵产物粗蛋白质含量由23.75%提高到35.75%,提高了11.00%,其中真蛋白质提高10.34%,粗纤维降低了2.05%,氨基酸总量由  相似文献   
86.
一体化间歇曝气完全混合活性污泥法处理装置采取特殊的沉淀区构造,改变了活性污泥的循环流动方式,通过间歇曝气,反应区交替处于好氧/缺氧状态,达到了有机物高效去除、高效硝化反硝化及控制污泥膨胀的效果.该方法具有出水水质好、运行稳定、能耗低、流程简洁和操作管理方便的特点,是一种很有发展潜力的一体化中小型生活污水、城市污水处理系统.  相似文献   
87.
A real-time, dynamic, early-warning model (EP-risk model) is proposed to cope with sudden water quality pollution accidents affecting downstream areas with raw-water intakes (denoted as EPs). The EP-risk model outputs the risk level of water pollution at the EP by calculating the likelihood of pollution and evaluating the impact of pollution. A generalized form of the EP-risk model for river pollution accidents based on Monte Carlo simulation, the analytic hierarchy process (AHP) method, and the risk matrix method is proposed. The likelihood of water pollution at the EP is calculated by the Monte Carlo method, which is used for uncertainty analysis of pollutants’ transport in rivers. The impact of water pollution at the EP is evaluated by expert knowledge and the results of Monte Carlo simulation based on the analytic hierarchy process. The final risk level of water pollution at the EP is determined by the risk matrix method. A case study of the proposed method is illustrated with a phenol spill accident in China.  相似文献   
88.
为了提高改良型Carrousel氧化沟工艺污水处理厂的脱氮除磷效果,结合某污水处理厂3年的运行实践,讨论了该工艺的处理效果,生物脱氮除磷原理及影响出水效果的因素.分析表明将DO控制在0.3~0.7 mg/L范围内,能够使出水中的TN浓度低于20 mg/L;在氧化沟中发生的同步硝化反硝化反应(SND)对总氮的去除的贡献占总系统脱氮的66%;该系统剩余污泥的含磷率为3.0%,生物细胞中平均含磷量可达细胞干重的4.2%;总磷去除率与污泥龄具有很好的线性关系,加大污泥排放量可以提高除磷效果.  相似文献   
89.
The impounding of the Three Gorges Reservoir (TGR) at the Yangtze River caused large flooding of urban, industrial, and agricultural areas, and profound land use changes took place. Consequently, substantial amounts of organic and inorganic pollutants were released into the reservoir. Additionally, contaminants and nutrients are entering the reservoir by drift, drainage, and runoff from adjacent agricultural areas as well as from sewage of industry, aquacultures, and households. The main aim of the presented research project is a deeper understanding of the processes that determines the bioaccumulation and biomagnification of organic pollutants, i.e., mainly pesticides, in aquatic food webs under the newly developing conditions of the TGR. The project is part of the Yangtze-Hydro environmental program, financed by the German Ministry of Education and Science. In order to test combinations of environmental factors like nutrients and pollution, we use an integrated modeling approach to study the potential accumulation and biomagnification. We describe the integrative modeling approach and the consecutive adaption of the AQUATOX model, used as modeling framework for ecological risk assessment. As a starting point, pre-calibrated simulations were adapted to Yangtze-specific conditions (regionalization). Two exemplary food webs were developed by a thorough review of the pertinent literature. The first typical for the flowing conditions of the original Yangtze River and the Daning River near the city of Wushan, and the second for the stagnant reservoir characteristics of the aforementioned region that is marked by an intermediate between lake and large river communities of aquatic organisms. In close cooperation with German and Chinese partners of the Yangtze-Hydro Research Association, other site-specific parameters were estimated. The MINIBAT project contributed to the calibration of physicochemical and bathymetric parameters, and the TRANSMIC project delivered hydrodynamic models for water volume and flow velocity conditions. The research questions were firstly focused on the definition of scenarios that could depict representative situations regarding food webs, pollution, and flow conditions in the TGR. The food webs and the abiotic site conditions in the main study area near the city of Wushan that determine the environmental preconditions for the organisms were defined. In our conceptual approach, we used the pesticide propanil as a model substance.  相似文献   
90.
本文就鉴赏类课程中现代教育技术的开发与应用的问题进行研究,结合现代教育技术的特征和鉴赏类课程自身的特点,提出了教学资源网络化、教学过程多媒体化、教学评价自动化等观点。  相似文献   
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