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51.
Desertification has recognized as an environmental problem by many international organizations such as UN, NATO and FAO. Desertification in Turkey is generally caused by incorrect land use, excessive grazing, forest fires, urbanization, industry, genetic erosion, soil erosion, salinization, and uncontrolled wild type plants picking. Due to anthropogenic destruction of forest, steppe flora gradually became dominant in Anatolia. In terms of biodiversity, Turkey has a significant importance in Europe and Middle East. Nine thousands plant species naturally grown in Turkey, one third of them are endemic. Also, endemic species of vertebrates, thrive in the lakes and marshy areas. The studies of modelling simulation of vegetation on the effects of Mediterranean climate during the Roman Classical period by using vegetation history showed that, in 2000 years BP, Mediterranean countries were more humid than today. Turkey is a special place on the global concern in terms of desertification because of biodiversity, agricultural potential, high population, social and economical structure, topographical factors and strategic regional location. Communication among scientists, decision makers and international non-profit organizations must be improved.  相似文献   
52.
Abstract

This study deals with the estimation of electricity production from hydraulic and thermal sources using the Genetic Algorithm (GA) with time series (TS) approach. Two forms of the mathematical models are developed, of which one is exponential and the second is polynomial. The power form of the Genetic Algorithm-Time Series (GATS) model is used for the thermal electricity production. The polynomial form of the GATS is used for the electricity production from the hydraulic sources. The GATS weighting parameters are obtained by minimizing the Sum of Squared Error (SSE) between observed and estimated electricity production from both sources. Therefore, the fitness function adapted is the minimization of the SSE for use in the GA process. The application of the GATS model is correspondingly presented. Some future scenarios are made to increase the electricity production from hydraulic sources. Variations of the electricity production from thermal and hydraulic energy sources are analyzed. Future prospects of electricity production are dealt with in terms of policy changes. The GATS models are used for making scenarios for future electricity planning policy. Results also show if current trend continues, the thermal electricity production amounts to 75% of the total electricity production, which is undesirable for environmental concerns. Results also shows that if new policy is to move from the thermal to hydraulic electricity production, the hydraulic sources will meet the demand until 2020.  相似文献   
53.
Although sunshine duration (SD) is one of the most frequently measured meteorological parameters, there is a lack of measurements in some parts of the world. Hence, it should be estimated accurately for areas where no reliable measurement is possible. The main objective of this study is to evaluate the potential of support vector machine (SVM) approach for estimating daily SD. For this purpose, three different kernels of SVM, such as linear, polynomial, and radial basis function (RBF), were used. Different combinations of five related meteorological parameters, namely cloud cover, maximum temperature (Tmax), minimum temperature (Tmin), relative humidity (RH), and wind speed (WS), and one astronomic parameter, day length, were considered as the inputs of the models, and the output was obtained as daily SD. Simulated values of the models were compared with ground measured values, and concluded that the usage of the SVM-RBF estimator with combination of all input attributes produced the best results. The coefficient of determination, root mean square error, and mean absolute error were found to be 0.8435, 1.5105 h, and 1.0771 h, respectively, for the pooled four-year daily data set of 14 stations in Turkey. It was also deduced that accuracy increased as the number of attributes increased and the major contribution to this came from RH as compared with Tmax, Tmin, and WS. This study has shown that the SVM methodology can be a good alternative for conventional and artificial neural network methods for estimating daily SD.  相似文献   
54.
简要介绍了 1 999年土耳其伊兹米特地震的有关情况 ,包括 :震中附近地区的经济地位、构造背景、地震活动背景、震前地震预报研究国际合作情况 ;这次地震造成的地震灾害、破坏特征和灾害严重的主要原因以及土耳其对地震灾害的法制管理工作等  相似文献   
55.
The rapidly growing population, increased urbanization, and intensive industrial and agricultural activities cause degradation and pollution of natural resources, soil erosion, and changes in hydrologic regimes in all over the world. To overcome these situations, it is necessary to develop an effective and holistic management methodology, called Integrated River Basin Management (IRBM). It is an internationally accepted administrative tool.IRBM is also one of the implementation requirements of the European Commission Water Framework Directive (WFD, 2000/60/EC) for European Union (EU) member states and candidate countries. Turkey, as an EU candidate country, already has started and continues to work toward adaptation of the WFD. Since the early 2000s, river basin studies have been undertaken to help integrate the WFD into Turkish legislation. Although Turkey has a strong legislative background, there are many challenges in this transition period because of several big river basins, the lack of environmental infrastructure, and the cost of carrying out the WFD.This paper analyses the political, legislative, and institutional advances of the implementation of IRBM in Turkey. Before the assessments of the new Turkish legislation developments and new basin institutions, the general principles of IRBM are explained. Finally, some recommendations for improving the effectiveness of the new basin organizations and water legislation are presented.  相似文献   
56.
From feathers to syngas - technologies and devices   总被引:1,自引:0,他引:1  
The poultry waste produced by industrial slaughterhouses typically contains not only feathers, but also a mixture of animal entrails, nails, blood, beaks and whole carcasses. Economical utilisation of this mixture, varying strongly in composition and moisture content, is, in general, difficult. We demonstrate that this awkward material can be successfully used for gasification in a simple, fixed-bed gasifier. The method of gasification, which we developed, enables control of the gasification process and ensures its stability in the operational regime of a working poultry processing plant. The installation, which has been working in Poland for 2 years, utilises 2 tons of feathers per hour and produces syngas of stable composition and fairly high quality. The syngas is burnt in the combustion chamber adjacent to the gasifier. Heat is recuperated in a boiler producing 3.5 tons per hour of technological steam continuously used for the operation of the slaughterhouse. The whole process complies with the stringent emission standards. In the paper we present the end-use device for feather utilisation and describe the underlying gasification and syngas combustion processes. Key elements of the whole installation are briefly discussed. The environmental impacts of the installation are summarized.  相似文献   
57.
The study consists of two parts. One part deals with recreation and vacation demands; the other investigates the relationship between recreation demand and some natural landscape elements preferred in the eastern Black Sea coastal zone of Turkey, which has traditionally a rich recreational culture. Home interview surveys were conducted during the summer of 1992. The recreation demand of the study area has been found to be 89.3% including potential demand. The landscape element "sea and seaside" preferred for recreation has been rated the highest in all groups of each of the five variables, namely, age, education, income, occupation, and marital status. The research reported here represents an empirical contribution to the field of landscape preference studies for recreation, especially in the developing countries.  相似文献   
58.
We explored the spatial variation in diatom communities withinthe Turkey Lakes Watershed (TLW). The TLW is a single watershed in an old growth sugar maple forest that contains an alternatingseries of stream and lake embayments. Near the outlet of each lake, we sampled pools and riffles to determine abundance and diversity of diatom communities along this hydrologic system. Diatom diversity, measured by Shannon-Weaver Index, richness andevenness, increased steadily downstream before eventually decreasing near the watershed outlet. Canonical CorrespondenceAnalysis indicated that diatom genera were correlated with streamchemistry. Upper reaches were the least productive, characterizedby lower pH (<7), higher N:P (113:1 to 124:1, dominated by complex forms of N), and high mean relative abundances of Eunotia spp., Tabellaria spp., and Pinnularia spp. Middle and lower reaches were more productive, characterized byhigher pH (>7), lower N:P (71:1 to 90:1, dominated by simple forms of N, e.g., nitrate-N), and high mean relative abundances of Cymbella spp. and Brachysira spp. Achnanthesminutissima (Kutz.) Hustedt, the most abundant species, and Navicula spp., Nitzschia spp., Gomphonema spp., and Frustrulia spp. were represented at all stream sites. Thisstudy revealed that within the TLW, a hydrologic system of the same stream order, the diatom community was influenced by a nutrient gradient, where the stream and its intervening lakes contributed to a shift from acidic, inorganic N-poor upper reaches to a circum-neutral, inorganic N-richer outlet. By imparting genera-specific stresses, stream flow (i.e. pools vs. riffles) further shaped the diatom community.  相似文献   
59.
Ezgi Orhan 《Disasters》2016,40(1):45-64
The lack of attention paid to businesses in disaster management systems from the standpoint of state policies hampers efforts to build community resilience. This paper examines, therefore, the extent of business preparedness for disasters. Empirical research was conducted in Adapazarı, Turkey, 13 years after the İzmit earthquake, which struck the northwest of the country on 17 August 1999, claiming the lives of some 17,000 people. For the study, 232 firms were selected to inquire about their preparedness before and after the event. It is hypothesised that business preparedness is influenced by the following set of variables: business size; business sector; business age; financial condition prior to the disaster; occupancy tenure; market range; education level; and previous disaster experience. In line with the findings of the research, a policy framework is constructed to rationalise the allocation of resources for building resilience at the aggregate level by facilitating business preparedness.  相似文献   
60.
Background, aim, and scope  Dicofol is widely used as a pesticide in agriculture applications. Since dicofol is mainly synthesized from dichlorodiphenyltrichlorethane (DDT), it contains DDT as an impurity. The European Community has forced Prohibition Directive 79/117/EEC to reduce DDT in dicofol formulations. Specifically, DDT content in a dicofol formulation cannot exceed 0.1%. The goal of this project was to determine the DDT content in dicofol formulations used in Turkey. Materials and methods  Samples of all the dicofol formulations in Turkey were collected to quantify DDT and DDT-related compounds. Four replicates were used for each sample. GC/MS/MS was used to analyze p,p′ and o,p′ isomers of DDT, DDD, and DDE. A HPLC was used to determine p,p′-Cl-DDT concentrations. Results  The total DDT content of the formulated dicofol was found between 0.3% and 14.3%. The concentration of p,p′-DDE ranged from 167 to 1,042 mg kg−1 in dicofol samples. p,p′-DDT concentrations were found to be 32 to 183 mg kg−1. The o,p’-DDT level ranged from 2 to 34 mg kg−1 in the dicofol formulations analyzed. Discussion  It was estimated that 617.8 kg of DDT was released from dicofol. The main impurity was identified as p,p-Cl-DDT. Based on these results, dicofol serves as a continuing source of DDT contamination. Conclusions  All DDT concentrations in dicofol samples analyzed were higher than the permitted 0.1% level of Prohibition Directive 79/117/EEC. The reduction of dicofol is critical since it serves as a continual source of DDT contamination. Recommendations and perspectives  DDT has been found in soil, water, and air samples. Dicofol has been identified as a contributor to continued DDT contamination in soil and water. More studies are needed to ascertain the source of DDT in the air.  相似文献   
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