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421.
Diarmuid Torney 《环境政策》2019,28(6):1124-1144
ABSTRACT

The past decade has seen the introduction of framework climate change laws in several countries. The development of climate laws in two small European states, Ireland and Finland, both of which introduced national climate laws in 2015, are examined. Two questions are addressed. First, to what extent do later adopters of climate policy instruments draw on the examples of pioneering legislation? Second, how and why are pioneering climate policy instruments modified by later adopters? In both cases, the 2008 UK Climate Change Act was a source of inspiration in the early stages, particularly for civil society campaigns. Thereafter, domestic interests mobilised to remove from legislative proposals the most pioneering and ambitious parts of the UK model. The result, in both cases, was enactment of climate laws that resembled only very loosely the UK Climate Change Act.  相似文献   
422.
A mathematical model describing the dissolution of nuclear glass directly disposed in clay combines a first-order dissolution rate law with the diffusion of dissolved silica in clay. According to this model, the main parameters describing the long-term dissolution of the glass are ηR, the product of the diffusion accessible porosity η and the retardation factor R, and the apparent diffusion coefficient Dapp of dissolved silica in clay.For determining the migration parameters needed for long-term predictions, four Through-Diffusion (T-D) experiments and one percolation test have been performed on undisturbed clay cores. In the Through-Diffusion experiments, the concentration decrease after injection of 32Si (radioactive labelled silica) was measured in the inlet compartment. At the end of the T-D experiments, the clay cores were cut in thin slices and the activity of labelled silica in each slice was determined. The measured activity profiles for these four clay cores are well reproducible.Since no labelled silica could be detected in the outlet compartments, the Through-Diffusion experiments are fitted by two In-Diffusion models: one model assuming linear and reversible sorption equilibrium and a second model taking into account sorption kinetics. Although the kinetic model provides better fits, due to the sufficiently long duration of the experiments, both models give approximately similar values for the fit parameters. The single percolation test leads to an apparent diffusion coefficient value about two to three times lower than those of the Through-Diffusion tests.Therefore, dissolved silica appears to be strongly retarded in Boom Clay. A retardation factor R between 100 and 300 was determined. The corresponding in situ distribution coefficient Kd is in the range 25–75 cm3 g−1. The apparent diffusion coefficient of dissolved silica in Boom Clay is estimated between 2×10−13 and 7×10−13 m2 s−1. The pore diffusion coefficient is in the range from 6×10−11 to 1×10−10 m2 s−1.  相似文献   
423.
Acetochlor is a widely used herbicide all over the world. Similarly to other organic pollutants, the environmental fate of the acetochlor is strongly related to its adsorption properties. Static adsorption equilibrium measurements were carried out at 25 degrees C on different types of Hungarian soils characterized by varying amounts of organic matter and pH values. Isotherms obtained under different conditions, as well as on various soils, exhibit a similar shape, thus indicating a two-step adsorption process. The plots cannot be interpreted according to the classes of isotherms suggested by Giles. The adsorption coefficients (K) were estimated from the initial slope of the curves. These values were determined not only by the type of the soil, but also by the composition of the aqueous media. The organic matter adsorption coefficients (Kom) were also calculated and they were approximately identical for soils of high organic matter. Due to the low value of the adsorption coefficients, the acetochlor is a rather mobile pollutant of the soil posing a potential danger to the aquatic environment. For soils with high organic content, the Kom values are similar to each other and, due to the significant coverage of the inorganic surfaces, the adsorption is controlled by the solute-organic substance interactions. The adsorption of weakly polar compounds, however, is remarkable even on those soils where the organic content is low. In this case, the binding is governed by the solute-inorganic surface interactions. This conclusion is nicely proved by the adsorption of the acetochlor on quartz. According to our hypothesis, the second part of the adsorption step is controlled by the solute-adsorbed solute interactions. The role of the organic matter in this region of the isotherm is probably negligible. As the organic matter content of the soils plays an important role in the acetochlor adsorption, humic substances must have a strong influence upon the transport of this compound. Experiments to obtain adsorption isotherms of further pesticides and the development of a quantitative model are in progress.  相似文献   
424.
水中有机成分及其对饮用水质的影响   总被引:3,自引:0,他引:3  
微量有机污染物和氯化消毒副产物对饮用水构成直接威胁,是饮用水中要重点控制的;天然大分子有机物对水质构成间接影响,导致胶体稳定性提高、增加药耗;藻类和代谢产物影响常规处理工艺效果,对水质产生不良影响。  相似文献   
425.
Transport experiments with colloids and radionuclides in a shear zone were conducted during the Colloid and Radionuclide Retardation experiment (CRR) at Nagra's Grimsel Test Site. Breakthrough curves of bentonite colloids and uranine, a non-sorbing solute, were measured in an asymmetric dipole flow field. The colloid breakthrough is earlier than that of uranine. Both breakthrough curves show anomalously long late time tails and the slope of the late time tails for the colloids is slightly higher. Anomalous late time tails are commonly associated with matrix diffusion processes; the diffusive interaction of solutes transported in open channels with the adjacent porous rock matrix or zones of stagnant water. The breakthrough curves for different colloid size classes are very similar and show no signs of fractionation due to their (size-dependent) diffusivity. It is proposed that tailing of the colloids is mainly caused by the structure of the flow field and that for the colloid transport, matrix diffusion is of minor importance. This has consequences for the interpretation of the uranine breakthrough. Comparisons of experimental results with numerical studies and with the evaluation of the colloid breakthrough with continuous time random theory imply that the tailing in the conservative solute breakthrough in this shear zone is not only caused by matrix diffusion. Part of the tailing can be attributed to advective transport in fracture networks and advection in low velocity regions. Models based on the advection-dispersion equation and matrix diffusion do not properly describe the temporal and spatial evolution of colloid and solute transport in such systems with a consistent set of parameters.  相似文献   
426.
对某潮汐河流从下游至上游共设A、B、C、D、E五个采样点,用Ames试验、双微核试验及单细胞凝胶电泳试验(彗星试验)检测涨潮和落潮时江水中有机污染物的致突变性.结果表明,Ames试验各采样点样品都有致突变性,且从上游至下游逐渐增强;对TA98加S9致突变性增加;双微核试验、彗星试验检测出染色体及DNA损伤剂,并以A点作用最强.涨潮时各点致突变强度较落潮时强.  相似文献   
427.
Effective diffusion coefficients (D(e)) are usually measured by means of "through-diffusion" experiments in which steady state is reached, and the "time-lag" methods are used to estimate the apparent diffusion coefficient (D(a)). For sorbing radionuclides (as caesium), the time needed to reach steady-state conditions is very large, and the precision in D(a) determinations is not satisfactory. In this paper, a method that allows determining simultaneously effective and apparent diffusion coefficients in compacted bentonite without reaching steady-state conditions is described. Basically, this method consists of an "in-diffusion" experiment in which the concentration profile in the bentonite sample is used to estimate D(a), and the temporal evolution of the solute concentration in the reservoir is used to estimate D(e). This method has several advantages over the typical "through-diffusion" experiments, in particular: (a) experiment duration is significantly shorter, (b) D(a) values are measured with greater precision and (c) it is not necessary to maintain a constant solute concentration in the reservoir. This new method has been used to estimate the effective and apparent diffusion coefficients for caesium in FEBEX bentonite and in order to validate it, the results have been compared with results previously obtained with standard methods. Experimental results have been satisfactorily modelled using a simple model of diffusion in porewater and the measured value of D(e)(Cs) is very similar to D(e)(HTO) in the same bentonite. There is no evidence of "surface diffusion" in FEBEX bentonite for caesium.  相似文献   
428.
菲、芘、1,2,4-三氯苯对蚯蚓的急性毒性效应   总被引:17,自引:0,他引:17  
测定了草甸棕壤条件下 ,菲、芘和 1,2 ,4-三氯苯单一与复合污染对蚯蚓的急性致死及亚致死效应。结果表明 ,3种化学品的浓度与蚯蚓死亡率显著相关 (α =0 .0 5 ,r菲 =0 .87,r芘 =0 .85 ,r三氯苯 =0 .95 ) ,与蚯蚓亚致死效应的相关性稍低 (α =0 .0 5 ,r菲 =0 .75 ,r芘 =0 .72 ,r三氯苯 =0 .85 )。蚯蚓个体对 3种有机物毒性的耐受程度差别较大。引起蚯蚓死亡的毒性阈值浓度菲和 1,2 ,4-三氯苯均为 2 0mg·kg-1,芘为 2 0 0 0mg·kg-1;引起蚯蚓体重增长率下降的亚急性毒性阈值浓度分别为菲 2 0mg·kg-1、1,2 ,4-三氯苯 3 0 0mg·kg-1、芘 10 0 0mg·kg-1;LC10 0 分别为菲 10 0mg·kg-1,1,2 ,4-三氯苯 3 5 0mg·kg-1。由于芘的低水溶性和低毒性 ,无法计算LC10 0 。实验还表明 ,复合污染主要表现为协同和拮抗作用  相似文献   
429.
阿特拉津降解菌的生长规律及降解特征的实验   总被引:2,自引:0,他引:2  
应用了从农药厂阿特拉津生产车间污泥中分离出的菌种AT菌,进行了菌种生长曲线的测定,求得AT菌的对数期代时为3.87d,生长速率为0.258d^-1;不同基质浓度的降解实验表明,在农药污染质阿特拉津的低浓度体系中,AT菌降解阿特拉津的反应符合一级动力学模式,属于米氏方程曲线的第一阶段的情形,并拟合出关系式V=0.064S。  相似文献   
430.
ADMs是新一代的大气扩散模型,用来评估空气污染扩散的问题。抚顺市2004年采取了大气污染治理措施并使用ADMs模型予以评估。仿真模拟的结果表明各项措施的效果并不和治理时的投资成比例,也不和污染物的削减总量成比例.说明治理过程中的科学性和经济性不够理想,也表明总量控制方针在实施中有许多实际问题需要解决。  相似文献   
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