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921.
长江产业带投资条件比较与综合分等评价   总被引:7,自引:2,他引:5  
将长江干流沿江地区建设成具有强大经济实力的国家级产业密集带是90年代国家调整宏观经济发展布局的重大战略举措。在大规模投资开发过程中如何按照各地投资环境特点,选择最佳的投资区位和适宜的投资方向是十分重要的。本文选取了能基本反映研究地区投资环境状况的基础设施条件,经济发展水平,科教发达程度,主要资源赋存和区域环境质量5类因素共14项指标,以产业带范围内的40个地市为地域单元,对产业带内部的投资环境条件  相似文献   
922.

Background, Aim and Scope

Metal ions generally share the ability/tendency of interacting with biological material by forming complexes, except possibly for the heavy alkali metals K, Rb and Cs. This is unrelated to the metals being either essential for sustaining life and its reproduction, apparently insignificant for biology, although perhaps undergoing bioconcentration or even being outright toxic, even at low admission levels. Yet, those different kinds of metal-biomass interactions should in some way depend on properties describing coordination chemistries of these very metals. Nevertheless, both ubiquitously essential metals and others sometimes used in biology should share these properties in numeric terms, since it can be anticipated that they will be distinguished from nonessential and/or toxic ones. These features noted above include bioconcentration, the involvement of metal ions such as Zn, Mg, Cu, Fe, etc. in biocatalysis as crucial components of metalloenzymes and the introduction of a certain set of essential metals common to (almost) all living beings (K, Mg, Mo, Mn, Fe, Cu and Zn), which occurred probably very early in biological evolution by ‘natural selection of the chemical elements’ (more exactly speaking, of the metallomes).

Materials and Methods

The approach is semiempirical and consists of three consecutive steps: 1) derivation of a regression equation which links complex stability data of different complexes containing the same metal ion to electrochemical data pertinent to the (replaced) ligands, thus describing properties of metal ions in complexes, 2) a graphical representation of the properties-two typical numbers c and x for each metal ion-in some map across the c/x-space, which additionally contains information about biological functions of these metal ions, i.e. whether they are essential in general (e.g. Mg, Mn, Zn) or, for a few organisms of various kinds (e.g. Cd, V), not essential (e.g. rare earth element ions) or even generally highly toxic (Hg, U). It is hypothesized that, if coordination properties of metals control their biological ‘feasibility’ in some way, this should show up in the mappings (one each for mono and bidentate-bonding ligands). 3) eventually, the regression equation produced in step 1) is inverted to calculate complex stabilities pertinent to biological systems: 3a) complex stabilities are mapped for ligands delivered to soil (-water) by green plants (e.g. citrate, malate) and fungi and, compared to their unlike selectivities and demands of metal use (photosynthesis taking place or not), 3b) the evolution of the metallome during late chemical evolution is reconstructed.

Results

These maps show some ‘window of essentiality’, a small, contrived range/area of c and x parameters in which essential metal ions gather almost exclusively. c and x thus control the possibility of a metal ion becoming essential by their influencing details of metal-substrate or (in cases of catalytic activities) metal-product interactions. Exceptions are not known to be involved in biocatalysis anyhow.

Discussion

Effects of ligands secreted, e.g. from tree roots or agaric mycelia to the soil on the respective modes (selectivities) of metal bioconcentration can be calculated by the equation giving complex stability constants, with obvious ramifications for a thorough, systematic interpretation of biomonitoring data. Eventually, alterations of C, N and P-compounds during chemical evolution are investigated — which converted CH4 or CO2, N2 and other non-ligands to amino acids, etc., for example, with the latter behaving as efficient chelating ligands: Did they cause metal ions to accumulate in what was going to become biological matter and was there a selectivity, a positive bias in favour of nowessential metals (see above) in this process? Though there was no complete selectivity of this kind, neither a RNA world in which early ribozymes effected most of biocatalysis, nor a paleoatmosphere containing substantial amounts of CO could have paved the way to the present biochemistry and metallomes.

Conclusions

This way of reasoning provides a causal account for abundance distributions described earlier in the Biological System of Elements (BSE; Markert 1994, Fränzle &; Markert 2000, 2002). There is a pronounced change from chemical evolution, where but few transformations depended on metal ion catalysis to biology.

Recommendations and Perspectives

The application of this numerical approach can be used for modified, weighted evaluation of biomonitoring analytical data, likewise for the prediction of bioconcentration hazards due to a manifold of metal ions, including organometallic ones. This is relevant in ecotoxicology and biomonitoring. In combining apoproteins or peptides synthesized from scratch for purposes of catalysing certain transformations, the map and numerical approaches might prove useful for the selection of central ions which are even more efficient than the ‘natural’ ones, like for Co2+ in many Zn enzymes.
  相似文献   
923.
煤炭发电产业每年有大量废渣量,占用大量耕地并需支付大量环保费用,对环境的污染和危害越来越严重,如何解决煤炭发电产业废渣问题成为全国各地发展中的重要问题。本文以乌兰水泥集团公司作为实例,分析了电力-水泥产业共生循环经济模式,主要启示和建议为:①电力-水泥产业共生模式值得推广;②因地制宜,建立循环经济基地;③产业循环链的设计是关键;④不断进行循环利用技术研究;⑤拓展融资渠道;⑥引进人才,加大培训力度;⑦建设循环经济信息系统。  相似文献   
924.
Resource-based cities face vital economic, social, and environmental problems during their industrial transformation. Urban industrial structure is a traditional primary industrial pattern, which is resource-based and resource-intensive economy with low level technology and efficiency. They encounter tremendous pressure of unemployment and social security. Resources of such cities are on the verge of extinction, in addition, the environmental pollution and ecological conditions are becoming worse. The cities have significant institutional issues and their innovation capacity is inadequate. Therefore, it is necessary to carry out strategic innovations to realize the successful economic transformation of resource-based cities. The strategic innovations include innovation of development goals, equalization of social welfare, sustainable economic development, coordinative development between eco-environment and socioeconomy, and circular economy development strategies optimizing diversified industrial structures. In addition, forming eco-industrial system and changing traditional growth pattern, strategy of resource and industrial substitution and supplement, scientific and technological innovation strategy —late-comer's advantages of development of new high-tech ecocity development strategy and innovation of institutional mechanism and systems.  相似文献   
925.
The feasibility of using a chemical reaction-based approach for evaluating and modelling the role of adsorption reactions in determining the geochernical confinement capacity of natural geological barriers is being studied as part of an on-going R & D programme. The confined superficial aquifer underlying the Centre de Stockage de l'Aube facility, a geological barrier for this site, has been used as a case study with the following aims. First, development of a site characterisation protocol and demonstration of its use to determine the principal geochemical characteristics of aquifer materials using batch experiments and to represent the information obtained in terms of a chemical model. The experimental results obtained for Ni2+ partitioning as a function of total Ni, pH, total Ca and total solid can be satisfactorily represented in terms of reactions with an ion exchange site and a single amphoteric surface hydroxyl site with ferrihydrite reaction constants. A second objective is the incorporation of the reactions in a coupled geochemistry/transport code, and to verify the applicability of the coupled code predictions for Ni2+ mass transfer by comparison with the results obtained during column tracer experiments. The breakthrough curve and equilibrium solid phase Ni loading, predicted by a one-dimensional coupled model for a column tracer experiment, agree closely with observed data.Additional studies are underway to reduce model conditionality, to extend the adsorption model to other analogue cations and anions, to incorporate the effect of natural organic matter and to take into consideration precipitation/dissolution of amorphous Fe surface phases.  相似文献   
926.
Patancheru and Bolaram are satellite industrial towns nearHyderabad with over 300 large andmedium scale pharmaceutical, heavy engineering, paints, paperand chemical factories. The industriesof the area generate a cumulative 8 × 106 l/day ofeffluents which are being directly dischargedon to surrounding land, irrigation fields, and surface waterbodies which finally enter into theNakkavagu River a tributary of the Manzira River. The presentstudy on abundance and distributionpattern of toxic trace elements indicates the quantitativeaspect of pollution in the Nakkavagu Basin.Migration patterns drawn for TDS, toxic elements such as Cu,As, Se, Zn, B, Cr and iron indicate thatpollutants discharged by the industries are entering thesurface and groundwater system (aquifers) andare also migrating towards the Manzira River furtherdeteriorating the entire hydrological setup of the area.Entry and dispersion of pollutants in the hydrological systemis shown by distribution diagrams. Aconservative estimate indicates that the effect of pollutantson the agricultural lands and water bodiesextends 0.25 to 0.5 km to either side of the Nakkavagu Riverover a length of 25 km. In addition tothis, the movement of pollutants with ground water in thedownstream direction worsened thehydrological system and increased the possibility ofgeo-accumulation of pollutants in biota. Openwells, dug wells and tanks have become useless and redundantas the concentrations of Cu, Se, As,B, Cr and Fe have increased to 5 to 10 times the permissiblelimits. Several villages have beenaffected by the toxic pollutants in the area. The groundwatersystem is polluted over a large area asshown in elemental migration diagrams and is not potable.Tentatively an area of 20 sq km can becategorized as the worst affected by various pollutants.  相似文献   
927.
长江中游沿江地区具有特殊的战略地位,其产业带建设又面临上海浦东开发和三峡工程建设两大契机。必须扩大对外开放,建设开放型产业带;加快改革步伐,建立社会主义市场经济体系;以资源优化配置,促进长江产业带整体效益的提高;必须协调资源、环境与产业带建设的关系,加强基础产业,调整加工制造业,合理布局生产,实现持续发展。  相似文献   
928.
A series of laboratory scale batch slurry experiments were conducted in order to establish a data set for oxidant demand by sandy and clayey subsurface materials as well as to identify the reaction kinetic rates of permanganate (MnO(4)(-)) consumption and PCE oxidation as a function of the MnO(4)(-) concentration. The laboratory experiments were carried out with 31 sandy and clayey subsurface sediments from 12 Danish sites. The results show that the consumption of MnO(4)(-) by reaction with the sediment, termed the natural oxidant demand (NOD), is the primary reaction with regards to quantification of MnO(4)(-) consumption. Dissolved PCE in concentrations up to 100 mg/l in the sediments investigated is not a significant factor in the total MnO(4)(-) consumption. Consumption of MnO(4)(-) increases with an increasing initial MnO(4)(-) concentration. The sediment type is also important as NOD is (generally) higher in clayey than in sandy sediments for a given MnO(4)(-) concentration. For the different sediment types the typical NOD values are 0.5-2 g MnO(4)(-)/kg dry weight (dw) for glacial meltwater sand, 1-8 g MnO(4)(-)/kg dw for sandy till and 5-20 g MnO(4)(-)/kg dw for clayey till. The long term consumption of MnO(4)(-) and oxidation of PCE can not be described with a single rate constant, as the total MnO(4)(-) reduction is comprised of several different reactions with individual rates. During the initial hours of reaction, first order kinetics can be applied, where the short term first order rate constants for consumption of MnO(4)(-) and oxidation of PCE are 0.05-0.5 h(-1) and 0.5-4.5 h(-1), respectively. The sediment does not act as an instantaneous sink for MnO(4)(-). The consumption of MnO(4)(-) by reaction with the reactive species in the sediment is the result of several parallel reactions, during which the reaction between the contaminant and MnO(4)(-) also takes place. Hence, application of low MnO(4)(-) concentrations can cause partly oxidation of PCE, as the oxidant demand of the sediment does not need to be met fully before PCE is oxidised.  相似文献   
929.
The most informative characteristics of the zooplankton-community response to the effect of industrial wastewater from mines have been determined using water bodies of the Kola Peninsula as an example. It has been demonstrated that qualitative and quantitative characteristics of zooplankton depend on the degree of industrial pollution of a water body and adequately reflect differences in the conditions of zooplankton growth between the whole water bodies and their individual parts. The role of zooplankton as an indicator has been assessed and the possibility of including it in the system of monitoring of water objects has been substantiated.  相似文献   
930.
基于新经济地理学相关理论,针对江苏省沿江开发战略实施以后,制造业空间可能存在的变动,在整理和分析调查问卷资料的基础上,选择专业化指数和基尼系数2种方法来定量分析江苏省21个沿江省级以上开发区空间分工、制造业集聚和转移态势。结果表明:(1)2002~2006年江南沿江开发区通过向江北沿江开发区转移部分传统产业,逐渐形成了江南沿江技术/资本密集型制造业“中心”和江北沿江劳动密集型制造业“外围”的空间分工格局;(2)江南沿江开发区内部、江北沿江开发区内部尚未形成良好的分工关系;(3)受开发区发展阶段、区域产业政策、本地化资源供给和市场需求等因素影响,并未发现理论预期的普遍存在的产业集聚现象,仅纺织服装、石化、电力、塑料橡胶等产业呈现集中趋势.  相似文献   
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