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71.
本着系统思想, 运用F AHP法,依据现有相关数据和多位专家意见,从产业自身发展、产业与区域经济发展、产业与区域社会发展、产业与区域资源环境发展4个模块30个指标构建产业转移后可持续发展评价指标体系,建立包含指标间模糊关系矩阵和面向参评产业的模糊评价矩阵的评价模型。通过模型评价了2006~2009年江苏苏北各市转移产业的可持续发展水平和能力。模型结果表明:苏北五市近年来承接的产业已获得较好的生存能力和可持续发展能力,但从可持续发展度的分值来看,苏北各市转移产业的可持续发展水平还不高;相比于传统产业,各市目前转移产业的可持续发展水平普遍较高,但苏北五市承接的产业有较大的同构性。因此,苏北各市下一阶段应优先发展比较优势产业,错位承接转移产业并考虑其可持续发展能力的培育  相似文献   
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73.
通过丹阳市4个村320户农户实地问卷调查,分析了丹阳市宅基地使用权流转意愿的影响因素,由Logistic回归分析模型,给出了影响因素的驱动力、贡献率的数学表达。结果表明:文化程度、宅基地个数、家庭总收入等影响因素对流转意愿呈正相关;户主年龄、家庭人口数量等影响因素对流转意愿呈负相关。同一农户的影响因素在不同阶段对流转意愿度的贡献率不同,家庭收入和户主年龄是影响宅基地流转的主要因素,他们对宅基地流转分别起着推力和阻力作用,在相互作用过程中,两者之间彼此消长。实地抽样结果分析表明,丹阳农村户主文化程度若为初中且年龄在35岁时,家庭收入能达到34 000元的话,宅基地使用权流转意愿度超过50%。以后每年家庭收入能有一定增速的话,农户流转意愿度将持续保持在50%以上。  相似文献   
74.
随着我国经济的发展和社会转型,农民群体逐渐分化为不同职业的农民阶层,由于职业选择的不同以及生活环境的变化,农民在经济收入、产权偏好等方面都出现了巨大的差异,这导致他们对土地流转意愿与决策行为的选择也出现分化,因此,研究由于农民职业分化导致的产权偏好不同及对土地流转的影响就具有重要现实意义.本文利用笔者对江苏省实地问卷调查所得的数据,在理论分析与研究假说的基础上,运用Lagistic模型对农民职业分化、产权偏好与农村土地流转的关系进行了实证分析.研究结果表明:文化程度、职业类别、非农收入比重、是否具有非农就业技能、是否拥有转让权、地权稳定性、地区虚拟变量对土地流转有正向影响,年龄则对土地流转有负向影响,而农业劳动力人数、土地的养老保障作用和是否具有抵押权则对土地流转决策没有显著影响.基于上述研究结论,本文提出了应强化土地产权、完善产权结构、大力发展非农产业和提供非农就业机会、提高农村劳动力职业技术素质、逐步建立和完善农村社会保障体系等政策建议.  相似文献   
75.
本文运用1998-2007年中国工业32个行业面板数据,将工业各行业研发总支出划分为自主研发、国外技术引进和国内技术转移三个部分,在估算自主研发存量和技术引进存量的基础上,研究了自主研发、技术引进对工业能源消耗强度的影响,并考察了能源相对价格、FDI的进入程度以及工业内部行业结构等因素.研究表明,自主研发和国外技术引进对能源强度的影响存在行业差异.自主研发对全工业行业和高能源强度行业的能源强度有显著负效应,对低能源强度行业的影响不显著;国内技术转移对全工业行业和低能源强度行业的能源强度有显著负的影响,对高能源强度行业的影响不显著;国外技术引进在所有样本中对能源强度的影响均不显著.研究还发现,在低能源强度行业中,自主研发并没有与国外技术引进互为补充共同促进能源强度的下降;在高、低能源强度行业样本中,自主研发没有与国内技术转移形成互补优势,有助于能源强度的下降.  相似文献   
76.
ABSTRACT: Regression and time-series techniques have been used to synthesize and predict the stream flow at the Foresta Bridge gage from information at the upstream Pohono Bridge gage on the Merced River near Yosemite National Park. Using the available data from two time periods (calendar year 1979 and water year 1986), we evaluated the two techniques in their ability to model the variation in the observed flows and in their ability to predict stream flow at the Foresta Bridge gage for the 1979 time period with data from the 1986 time period. Both techniques produced reasonably good estimates and forecasts of the flow at the downstream gage. However, the regression model was found to have a significant amount of autocorrelation in the residuals, which the time-series model was able to eliminate. The time-series technique presented can be of great assistance in arriving at reasonable estimates of flow in data sets that have large missing portions of data.  相似文献   
77.
ABSTRACT .Many growing municipalities near irrigated agriculture are advocating a transfer of water now utilized for irrigation to municipal use. Alternatives are presented whereby this water can be transferred to municipal use in exchange for treated sewage effluent. The irrigation water would in effect be cycled through the municipal system prior to use on the farms. A case study of the Tucson region illustrates the relevant legal, economic and technical aspects. Effluent could be delivered to irrigators in Avra Valley at a cost less than that now paid for water pumped from declining water tables. In return the City of Tucson could import ground water now being used for irrigation through an existing pipeline which presently cannot be used because of a court injunction obtained by the irrigators. It appears that such an exchange agreement could be made without modification of existing statutory law. Similar exchange arrangements may prove to be feasible in other regions containing irrigated agriculture. Increased efficiency of water use can be achieved avoiding external effects which commonly arise in a direct transfer and are difficult to evaluate. High quality water is allocated to municipal use whereas nutrient-rich sewage effluent is transferred to irrigation.  相似文献   
78.
南水北调中线工程对汉江中下游工业发展的影响   总被引:14,自引:3,他引:11  
南水北调中线工程计划从丹江口水库向我国北方每年调水145亿m^3,汉江丹江口以下地区的水资源量将随之相应减少。汉江中下游地区是湖北省盐化工、机械、石油、食品、化肥、电力的重要生产地区,是湖北省的汽车工业走廊,其经济在湖北省占有举足轻重的地位。由于经济的迅速发展,下世纪工农业生产和人民生活对水资源的需求将从现在的140亿m^3增加到250亿m^3以上,需水量将达到水资源量的58%,潜伏着严重的水资源  相似文献   
79.
GOAL, SCOPE AND BACKGROUND: This paper uses two case studies of U.S. Department of Energy nuclear weapons complex installations to illustrate the integration of expedited site characterization (ESC) and multimedia modeling in the remedial action decision making process. CONCEPTUAL SITE MODELS, MULTIMEDIA MODELS, AND EXPEDITED SITE CHARACTERIZATION: Conceptual site models outline assumptions about contaminates and the spatial/temporal distribution of potential receptors. Multimedia models simulate contaminant transport and fate through multiple environmental media, estimate potential human exposure via specific exposure pathways, and estimate the risk of cancer and non-cancer health outcomes. ESC relies on using monitoring data to quantify the key components of an initial conceptual site model that is modified iteratively using the multimedia model. CASE STUDIES: Two case studies are presented that used the ESC approach: Los Alamos National Laboratory (LANL) and Pantex. LANL released radionuclides, metals, and organic compounds, into canyons surrounding the facility. The Pantex Plant has past waste management operations which included burning chemical wastes in unlined pits, burying wastes in unlined landfills, and discharging plant wastewaters into on-site surface waters. CONCLUSIONS: The case studies indicate that using multimedia models with the ESC approach can inform assessors about what, where, and how much site characterization data needs to be collected to reduce the uncertainty associated with risk assessment. Lowering the degree of uncertainty reduces the time and cost associated with assessing potential risk and increases the confidence that decision makers have in the assessments performed.  相似文献   
80.
Methods for life cycle assessment of products (LCA) are most often based on the general prevention principle, as opposed to the risk minimization principle. Here, the desirability and feasibility of a combined approach are discussed, along with the conditions for elaboration in the framework of LCA methodology, and the consequences for LCA practice. A combined approach provides a separate assessment of above and below threshold pollution, offering the possibility to combat above threshold impacts with priority. Spatial differentiation in fate, exposure, and effect modelling is identified to play a central role in the implementation. The collection of region-specific data turns out to be the most elaborate requirement for the implementation in both methodology and practice. A methodological framework for the construction of characterization factors is provided. Along with spatial differentiation of existing parameters, two newly introduced spatial parameters play a key role: the sensitivity factor and the threshold factor. The practicability of the proposed procedure is illustrated by an example of its application. Providing a reasonable data availability, the development of separate LCA characterization factors for the respective assessment of pollution levels above and below environmental threshold values seems to be a feasible task that may add to LCA credibility.  相似文献   
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