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排序方式: 共有104条查询结果,搜索用时 31 毫秒
51.
This article examines the role of building trust in Humanitarian Mine Action (HMA). The role of trust following a mine-clearance operation is largely an unexplored region. Drawing on case studies from Angola, Mozambique and Afghanistan, the article explores how trust can be understood in the context of humanitarian initiatives such as landmine clearance, and outlines the challenges associated with building trust among populations with experience of armed conflict. Because trust is difficult to re-establish following a war, the argument presented here suggests that one way in which this can be done is through building relationships at the organisational and interpersonal levels. The analysis reviews specific measures that mine-action agencies have used to build trust, looking at the strengths and weaknesses of different approaches. The analysis concludes by suggesting general guidelines for how mine-action practitioners can facilitate trust, and by outlining some promising avenues for future research.  相似文献   
52.
The aim of this paper is to consider whether some seats in a democratically elected legislative assembly ought to be reserved for representatives of future generations. In order to examine this question, I will propose a new democratic model for representing posterity. It is argued that this model has several advantages compared with a model for the democratic representation of future people previously suggested by Andrew Dobson. Nevertheless, the democratic model that I propose confronts at least two difficult problems. First, it faces insoluble problems of representative legitimacy. Second, one might question whether this model provides a reasonably effective way to represent future interests compared with existing representative democratic institutions. Despite such problems, it is argued that political representation of posterity can be defended on the basis of fundamental ideas and ideals in recent theory of deliberative democracy. The first reason for this is that in a number of cases democratic decisions cannot be regarded as normatively legitimate from the point of view of deliberative democracy, unless posterity is given a voice. The second reason is that representation of posterity can contribute to more rational and impartial deliberations and decisions in legislative assemblies.  相似文献   
53.
Olsen GR  Carstensen N  Høyen K 《Disasters》2003,27(2):109-126
This paper proposes a basic hypothesis that the volume of emergency assistance any humanitarian crisis attracts is determined by three main factors working either in conjunction or individually. First, it depends on the intensity of media coverage. Second, it depends on the degree of political interest, particularly related to security, that donor governments have in a particular region. Third, the volume of emergency aid depends on strength of humanitarian NGOs and international organisations present in a specific country experiencing a humanitarian emergency. The empirical analysis of a number of emergency situations is carried out based on material that has never been published before. The paper concludes that only occasionally do the media play a decisive role in influencing donors. Rather, the security interests of Western donors are important together with the presence and strength of humanitarian stakeholders, such as NGOs and international organisations lobbying donor governments.  相似文献   
54.
We here report the first sign of amphibian recovery after a strong decline due to acidic precipitation over many decades and peaking around 1980–90. In 2010, the pH level of ponds and small lakes in two heavily acidified areas in southwestern Scandinavia (Aust-Agder and Østfold in Norway) had risen significantly at an (arithmetic) average of 0.14 since 1988–89. Parallel with the general rise in pH, amphibians (Rana temporaria, R. arvalis, Bufo bufo, Lissotriton vulgaris, and Triturus cristatus) had become significantly more common: the frequency of amphibian localities rose from 33% to 49% (n = 115), and the average number of amphibian species per locality had risen from 0.51 to 0.88. In two other (reference) areas, one with better buffering capacity (Telemark, n = 21) and the other with much less input of acidic precipitation (Nord-Trøndelag, n = 106), there were no significant changes in pH or amphibians.  相似文献   
55.
56.
Kim JK  Metcalfe IS 《Chemosphere》2007,69(5):689-696
The presence and impact of hydroxyl radicals generated via the catalytic decomposition of H(2)O(2) over heterogeneous copper catalysts were investigated by using two detection methods, an electron spin resonance-spin trapping method and a chemical probe method. Detection of the (5,5-dimethyl-1-pyrroline-N-oxide)-OH adduct signal and formation of 4-chlorocatechol during the oxidation of a 4-chlorophenol substrate demonstrated that the three heterogeneous copper catalysts employed here (CuO, Cu/Al(2)O(3) and CuO.ZnO/Al(2)O(3)) were capable of generating hydroxyl radicals in combination with H(2)O(2). The oxidative mechanism of the hydroxyl radical in the presence of heterogeneous copper catalysts is discussed with regard to the further oxidation of the (5,5-dimethyl-1-pyrroline-N-oxide)-OH adduct and hydroxylated products of 4-chlorophenol oxidation. Interestingly, integration of the 5,5-dimethyl-1-pyrroline-N-oxide-OH adduct signal could not be used to reliably measure the total amount of hydroxyl radicals generated as a result of oxidative attack on the adduct. This may be as a result of locally higher hydroxyl radical concentrations in the presence of a heterogeneous catalyst leading to further unwanted oxidation of the (5,5-dimethyl-1-pyrroline-N-oxide)-OH.  相似文献   
57.
Toxaphene contamination of minke whales (Balaenoptera acutorostrata) from North Atlantic waters was examined for the first time. Total toxaphene and SigmaCHB (sum of 11 chlorobornanes) concentrations in blubber samples ranged from 170+/-110 and 41+/-39 ng/g lipid weight (l.w.) for female minke whales from southeastern Greenland to 5800+/-4100 and 1100+/-780 ng/g l.w. for males from the North Sea, respectively. Very large variations in toxaphene concentrations among sampling areas were observed suggesting a spatial segregation of minke whales. However, much of the apparent geographical discrimination was explained by the seasonal fluctuation of animal fat mass. Patterns of CHBs in males revealed that recalcitrant CHBs were in higher proportions in animals from the more easterly areas than in animals from the more westerly areas. This trend may be influenced by the predominance of the US, over the European, input of toxaphene to North Atlantic waters.  相似文献   
58.
Contrary to the assumptions of many previous theoretical models, group size has recently been shown in experiments to have an effect on the relative (as well as absolute) competitive abilities of group members. Here we introduce a novel and effective mathematical tool for describing how relative competitive ability will change for any two specified individuals within a group as group size changes. We show that there is no simple general rule for describing how relative competitive ability will change with group size. A subsequent empirical test of the model helps to illustrate that very specific knowledge of the system under study is needed in order to produce robust predictions. Received: 23 December 1998 / Received in revised form: 26 July 1999 / Accepted: 2 October 1999  相似文献   
59.
Li H  Helm PA  Paterson G  Metcalfe CD 《Chemosphere》2011,83(3):271-280
The effect of solution pH and levels of dissolved organic matter (DOM) on the sampling rates for model pharmaceuticals and personal care products (PPCPs) and endocrine disrupting substance (EDS) by polar organic chemical integrative samplers (POCIS) was investigated in laboratory experiments. A commercially available POCIS configuration containing neutral Oasis HLB (hydrophilic-lipophilic balance) resin (i.e. pharmaceutical POCIS) and two POCIS configurations prepared in-house containing MAX and MCX anion and cation exchange resins, respectively were tested for uptake of 21 model PPCPs and EDS, including acidic, phenolic, basic and neutral compounds. Laboratory experiments were conducted with dechlorinated tap water over a pH range of 3, 7 and 9. The effects of DOM were studied using natural water from an oligotrophic lake in Ontario, Canada (i.e. Plastic Lake) spiked with different amounts of DOM (the concentration of dissolved organic carbon ranged from 3 to 5 mg L−1 in uptake experiments). In experiments with the commercial (HLB) POCIS, the MCX-POCIS and the MAX-POCIS, the sampling rates generally increased with pH for basic compounds and declined with pH for acidic compounds. However, the sampling rates were relatively constant across the pH range for phenols with high pKa values (i.e. bisphenol A, estrone, estradiol, triclosan) and for the neutral pharmaceutical, carbamazepine. Thus, uptake was greatest when the amount of the neutral species in solution was maximized relative to the ionized species. Although the solution pH affected the uptake of some model ionic compounds, the effect was by less than a factor of 3. There was no significant effect of DOM on sampling rates from Plastic Lake. However, uptake rates in different aqueous matrixes declined in the order of deionized water > Plastic Lake water > dechlorinated tap water, so other parameters must affect uptake into POCIS, although this influence will be minor. MAX-POCIS and MCX-POCIS showed little advantage over the commercial POCIS configuration for monitoring in natural waters.  相似文献   
60.
Balch G  Metcalfe C 《Chemosphere》2006,62(8):1214-1223
The endocrine modulating potency of five alkylphenol compounds to fish, including nonylphenol (NP), three nonylphenol ethoxylate mixtures (NP1EO, NP4EO, NP9EO) and one nonylphenol ethoxycarboxylate (NP1EC) was assessed using in vivo tests conducted with Japanese medaka (Oryzias latipes). Medaka exposed to test materials from 1 day to 100 days post-hatch were monitored for alterations to sex ratios and secondary sex characteristics and development of gonadal intersex (i.e., testis-ova). The treatment with 100 microg l-1 NP (measured 29 microg l-1) induced gonadal intersex in over 80% of exposed males, mixed secondary sex characteristics in over 40% of exposed fish and suppression of the development of papillae on the anal fin of 100% of males. The 30 microg l-1 NP (measured 8.7 microg l-1) treatment induced gonadal intersex in only one of the 22 exposed males and mixed secondary sex characteristics in approximately 20% of the exposed fish. An elevated incidence of fish with mixed secondary sex characteristics and suppression of papillae development was also observed in the treatment with NP1EO at the highest test concentration of 300 microg l-1 (measured 105 microg l-1). There was no evidence of mixed secondary sex characteristics or gonadal intersex in treatments with the remaining test mixtures. This study confirms that NP is an estrogenic compound that could affect gonadal development in fish chronically exposed to concentrations in the range of 10 microg l-1. NP1EO is very weakly estrogenic at concentrations that are an order of magnitude higher than the lowest observed effect concentration for nonylphenol.  相似文献   
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