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91.
A new method to single out the environmental factor limiting the life of any macrobenthic animal under stressed condition is proposed. The method is based on the assumption that the influence of each environmental factor on the life of a species can be expressed by an S-shaped function having lethal, limiting and non-limiting ranges, and the combined effect of several environmental factors is expressed by a multiple of these functions. To single out a lethal factor, we used the cumulative curve of abundance arranged in the order of each environmental factor. Comparison of these curves enables us to identify the most effective environmental factor limiting the life of a particular species and determine its effective range. Determination can be made from a single field observation without recourse to specially prepared experimental data if a sufficiently extensive survey was made in a field observation. The method was applied to the field data obtained from 248 stations at Lake Shinji, Japan, in the summer of 1982.  相似文献   
92.
This paper investigates the impacts of Tropical Cyclone Winston (2016) on rural Indo-Fijians and their response to the devastation. Studies have previously examined how rural communities in Pacific Island countries respond to severe climatic events, arguing that traditional knowledge of the climate, together with indigenous techniques, contribute substantially to recovery from a disaster. Strong communal bonds have also been identified as an influencing factor. Disaster risk reduction frameworks often assume the availability of such knowledge and capital. Yet, little research has been done on how minority groups with limited access to such knowledge and capital cope with disaster-related damage. The current study shows that rural Indo-Fijians responded to the consequences of Tropical Cyclone Winston differently to indigenous Fijians, owing to relatively limited access to traditional awareness of the climate, communal labour sharing, and intra- and/or inter-community networks. The findings point to the necessity to implement a more inclusive disaster risk reduction framework.  相似文献   
93.
Spatiotemporal recruitment patterns of scleractinian corals were investigated around Iriomote Island, Ryukyu Archipelago, Japan, in relation to adult coral cover in 2005 and 2006. Although almost all corals were broadcasting spawners, the relationship between recruitment and adult coral cover differed among coral families (Acroporidae, Poritidae, and Pocilloporidae), likely due to differences in embryonic development time. For spawning pocilloporid corals, whose larvae develop relatively more rapidly, recruitment was higher at sites where adult coral cover was higher. In contrast, recruitment was not related to adult coral cover in acroporid and poritid corals, whose embryonic development times were relatively slow. Moreover, recruitment of acroporid corals varied between years, and recruitment was greater at leeward compared to windward reefs for a few days after spawning. These results suggest that embryonic development time and wind-driven surface currents affect larval dispersal and subsequent recruitment patterns at a local scale. Based on embryonic development time, some spawning corals are more likely to have higher rates of self-seeding than others. Our results predict that among spawning corals, local populations of acroporid and poritid corals, whose larvae potentially disperse over long distances and recruit in neighboring reefs, are more resilient to local disturbances than those of pocilloporid corals, whose recruitment relies upon local stock.  相似文献   
94.
The apparent aqueous solubility of the endocrine disruptor in hydroxypropyl‐cyclodextrin (HP‐CD) solutions was investigated for evaluating the remediation of soil contamination and ground water pollution. The apparent solubility of bisphenol A (BPA) in water was significantly increased in HP‐CD solutions. The solubilization effect of HP‐CD's is caused by the formation of inclusion complexes of BPA and cyclodextrin. The relative aqueous‐phase concentration of BPA linearly increased with increasing HP‐CD concentration. The solubility of BPA increased in the order of the addition of HP‐a‐CD, HP‐7‐CD, and HP‐ß‐CD. However, it did not depend upon the degree of hydroxypropylation substitution. It is concluded that HP‐CD may be utilized for the remediation of soil contamination.  相似文献   
95.
Seagrass beds are often considered to be important nurseries for coral reef fish, yet the effectiveness of these nursery functions (refuge and food availability) at different juvenile stages is poorly understood. To understand how the demands of juvenile fish on seagrass nursery functions determines the timing of ontogenetic habitat shifts from seagrass beds to coral reefs, we conducted visual transect survey and field tethering and caging experiments on three different sizes of the coral reef fish Pacific yellowtail emperor (Lethrinus atkinsoni) during its juvenile tenure in seagrass beds at Ishigaki Island, southern Japan. The study showed that although the number of individual L. atkinsoni juveniles decreased by >90 % during their stay in the seagrass nursery, the shelter and/or food availability functions of the nursery, at least for a juvenile size of approximately 5 cm total length (TL), provided the best survival and growth option. The timing of ontogenetic migration to coral reefs of larger fish (>8 cm TL) was attributed to foraging efficiency for larger food items in different habitats. Overall, the function of the seagrass bed nursery changed with juvenile body size, with marginally higher survival and significantly greater growth rates during early juvenile stages in seagrass beds compared to coral reefs. This would contribute to the enhancement in the number of individuals eventually recruited to adult populations.  相似文献   
96.
The circumstances of the lack of attention to the interdependence of family functions and external employment in the research to date are considered. Major problems and barriers to progress are noted. One problem is the conceptual-theoretical barrier of viewing work as masculine and family responsibility as feminine. A second problem is a differential focus in the research to date in which either the family is studied with inadequate attention given to work, or the work setting is studied with insufficient consideration of family responsibilities. Research strategies are reviewed and discussed, including the need to identify combinations of types of occupations and family situations. Five work-family groups are identified. One of the five groups, single parent is used to illustrate policies pertaining to the interdependence of work and family roles. The relevance of research on role interdependence for both governmental policy and organizational policy is considered in a discussion of the effects of policy on effective integration of work and family roles.  相似文献   
97.
The salting-out effect by seawater constituents on the water solubilities of 11 aromatic compounds, anthracene, pyrene, phenanthrene, biphenyl, naphthalene, p-nitrotoluene, p-toluidine, o-nitrophenol, m-nitrophenol, p-nitrophenol and phenol was investigated. A best fit equation (r = 0.965) for the salting-out parameters, K, and distilled water solubilities, So, at 20°C was found to be K = ?0.0298 log So + 0.114. Seawater solubilities, S, predicted for solutions of ionic strength, I, using the equation log S = (0.0298 I + 1) log So ? 0.114 I were in agreement with observed values within 13 % (average 4.8 %) and there were no significant differences between values from the Pacific Ocean seawater and those from 35 o/oo NaCl solutions. It was concluded that dissolved organic matter in seawater had an insignificant effect for the test chemicals.  相似文献   
98.
The explosive self-decomposition characteristics of gaseous ozone with a concentration of up to almost 100 vol% were quantitatively investigated using a closed system with an electric spark device. The lower self-decomposition (explosion) limit for ozone diluted with oxygen at room temperature and atmospheric pressure was 10–11 vol%, and so ozone at more than 10–11 vol% will lead to an explosive chain decomposition reaction leading to its complete conversion to oxygen in a vessel. The lower explosion limit shifts to a higher concentration with a decrease in pressure. The limit was about 80 vol% under a reduced pressure of 10 Torr. We also confirmed that explosion trigger energy (minimum ignition energy) is strongly dependent on ozone concentration and pressure. For example, the minimum trigger energy for 15 vol% ozone at a pressure of 76 Torr (about 220 mJ) was more than 20-fold that at atmospheric pressure (about 10 mJ), and that for 13 vol% ozone (about 580 mJ) was approximately 30 times higher than that for 20 vol% (about 20 mJ) at the same pressure of 76 Torr. Moreover, the physical characteristics of the trigger energy sources (e.g. spark gap and electrode tip angle) leading to the decomposition (explosion) of ozone were investigated under various conditions.  相似文献   
99.
ABSTRACT: Since the 1970s, there has been extensive experimentation with new approaches to water and land resources management at the state and local levels. There is a critical need to document, assess, and synthesize lessons learned from the nation's recent experience with subnational institutional changes in environmental management. This paper examines institutional changes aimed at more integrated water and related resources management at the substate level of government. We describe innovative institutional changes in a case study of Dane County, Wisconsin, and assess the implementation and preliminary consequences of these changes. Dissatisfaction with watershed and lake management results and perceptions of institutional inadequacy led to significant changes in the structure and rules for county resources management. A new entity was created to focus watershed management responsibilities. The scope of authority and powers were expanded. However, these changes all occurred within the framework of a general purpose unit of government. The new institutional arrangements have achieved a number of milestones, although it is premature to fully assess resource outcomes. The substantive changes, implementation tactics, and overall experience in Dane County's reforms - especially with regard to addressing intergovernmental tensions and decentralized management, limited authorities and funding, and public and constituency support - have useful implications for other substate efforts at more comprehensive and integrated water resources management.  相似文献   
100.
Ishii N  Tagami K  Uchida S 《Chemosphere》2004,57(8):953-959
The behavior of an element in the environment depends on its physicochemical form. Basic data for the behavior of technetium in an agricultural environment were obtained by determining the physicochemical forms of Tc in 28 surface water samples from paddy and upland fields. Most of the (95m)Tc was present as TcO(4)(-) in the samples. The relative amount of this chemical form was 72% on average. A significant amount of insoluble Tc (particles more than 0.2 microm in size), however, was found in some samples. The maximum amount of the insoluble Tc was 91%. Other forms were found in insignificant amounts. The amount of insoluble Tc was relatively high in paddy soil samples. Paddy soils, gley soils and gray lowland soils were particularly effective in the insolubilization of Tc. Among the soil characteristics studied, cation exchange capacity, anion exchange capacity, and active aluminum showed significant correlations with the relative amount of insoluble Tc. When microorganisms were eliminated from the surface water samples before the addition of (95m)TcO(4)(-), little insoluble Tc was found, suggesting that microorganisms cause the physicochemical transformation. These results showed that the physicochemical form of Tc changes from TcO(4)(-) to insoluble forms in surface water covering paddy fields. The insoluble forms would restrict the mobility of Tc in paddy fields.  相似文献   
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