首页 | 本学科首页   官方微博 | 高级检索  
文章检索
  按 检索   检索词:      
出版年份:   被引次数:   他引次数: 提示:输入*表示无穷大
  收费全文   423篇
  免费   5篇
  国内免费   20篇
安全科学   13篇
废物处理   57篇
环保管理   47篇
综合类   41篇
基础理论   64篇
环境理论   3篇
污染及防治   126篇
评价与监测   54篇
社会与环境   40篇
灾害及防治   3篇
  2023年   19篇
  2022年   74篇
  2021年   34篇
  2020年   8篇
  2019年   19篇
  2018年   25篇
  2017年   27篇
  2016年   29篇
  2015年   10篇
  2014年   22篇
  2013年   34篇
  2012年   11篇
  2011年   26篇
  2010年   24篇
  2009年   19篇
  2008年   12篇
  2007年   9篇
  2006年   7篇
  2005年   6篇
  2004年   8篇
  2003年   4篇
  2002年   3篇
  2001年   2篇
  2000年   3篇
  1997年   1篇
  1996年   3篇
  1995年   3篇
  1994年   1篇
  1991年   2篇
  1985年   1篇
  1984年   1篇
  1963年   1篇
排序方式: 共有448条查询结果,搜索用时 218 毫秒
91.
Detection of norovirus (NoV) and hepatitis A virus (HAV) on fruits and vegetables using current standard methodologies can be inefficient. Method optimisat  相似文献   
92.
Journal of Polymers and the Environment - In this work, the use of carboxymethyl cellulose (CMC) is highlighted in enhancing the controlled release behaviour of zinc/aluminium layered double...  相似文献   
93.
ABSTRACT

This study investigates the structural linkages of product quality, corporate image, store image, and price on customer satisfaction and loyalty towards green products usage in Malaysia. The research used structural equation modelling technique via AMOS 21.0 computer program for data analysis across a sample of 200 university students who applies a green lifestyle, such as purchasing green products which are referring to only retail goods, using recyclable products, and ozone-free products. Empirical analysis divulged that product quality followed by corporate image, store image, and product price jointly affected customer satisfaction in using green products. They are highly concerned that the green store provides a variety of good quality products with good value for money. Marketers should aggressively promote the identification of green products and overcome the problem of just noticeable difference between green product and non-green product among consumers for business sustainability. Empirical findings provide valuable insights to put forth in outlining effective marketing strategies that widen the marketers’ understanding of consumer behaviour in using green products with regard to their satisfaction and loyalty levels from the perspective of product quality, corporate image, store image, and product prices in Malaysia markets.  相似文献   
94.
Healthcare waste management (HCWM) options are inconsistent in Bangladesh. One of the first critical steps in the process of developing a reliable waste management plan requires a comprehensive understanding of the quantities and characteristics of the waste that needs to be managed. This study took into consideration both the quantity and quality of the generated waste to determine the generation rates and physical properties of healthcare waste (HCW) in Chittagong Medical College Hospital (CMCH) and also to estimate the amount of infectious and non-infectious waste generated in different wards. CMCH, the second largest hospital in Bangladesh, comprises 34 wards, 12 of which were selected randomly. Waste materials were collected from these wards and then segregated and weighed. Waste generation per day was found to be 73.22 kg/ward, 1.28 kg/bed and 0.57 kg/patient. A total of 2490 kg of HCW was produced each day in CMCH (37% being infectious and the rest being non-infectious waste). Infectious waste was 27.07 kg per ward, 0.47 kg per bed and 0.21 kg per patient and the non-infectious waste was 46.15 kg per ward, 0.81 kg per bed and 0.36 kg per patient per day. HCW comprised eight categories of waste materials with vegetable/food waste being the largest component (50.21%) and varied significantly (P < 0.05) among the 12 different wards studied. The greatest amount of HCW was recorded (154 kg) in Orthopaedics followed by 96.66 kg in the Medicine Unit-3 and the smallest amount was recorded in Casualty (8.79 kg). The amount of HCW was positively correlated with the number of occupied beds (rxy = 0.79, P < 0.01). There is no structured form of medical waste treatment in CMCH and most waste materials are dumped in open areas for natural degradation or re-sold by scavengers. It is essential to develop a national policy and implement a comprehensive action plan for HCWM that will provide environmentally sound technological measures to improve HCWM in Bangladesh.  相似文献   
95.
Statistic and econometric regression models were established in this study to analyze and predict industrial water demand, water deficits, and their future uncertainty in Beijing—a Chinese city with a severe water stress problem. A forecasting model was selected based on a modeling evaluation by comparing predictions with observations. Four scenarios were designed to simulate and analyze the future uncertainty of industrial water demand and the water deficit of Beijing. The modeling results for industrial water demand suggested that Beijing industry would face a water deficit between 3.06 × 108 m3 in 2008 and 2.77×108 m3 in 2015, though its industrial water demand would decrease from 6.31×108 m3 to 4.84 ×108 m3 during this period of time. Results from simulated scenario illustrated that, due to the extreme water scarcity situation, industry in Beijing would still face a serious water deficit problem even with a very optimistic scenario for the future.  相似文献   
96.
The aim of this study was to investigate the feasibility of using visible near-infrared (VisNIR) diffuse reflectance spectroscopy (DRS) as an easy, inexpensive, and rapid method to predict compost enzymatic activity, which traditionally measured by fluorescein diacetate hydrolysis (FDA-HR) assay. Compost samples representative of five different compost facilities were scanned by DRS, and the raw reflectance spectra were preprocessed using seven spectral transformations for predicting compost FDA-HR with six multivariate algorithms. Although principal component analysis for all spectral pretreatments satisfactorily identified the clusters by compost types, it could not separate different FDA contents. Furthermore, the artificial neural network multilayer perceptron (residual prediction deviation = 3.2, validation r2 = 0.91 and RMSE = 13.38 μg g?1 h?1) outperformed other multivariate models to capture the highly non-linear relationships between compost enzymatic activity and VisNIR reflectance spectra after Savitzky–Golay first derivative pretreatment. This work demonstrates the efficiency of VisNIR DRS for predicting compost enzymatic as well as microbial activity.  相似文献   
97.
The pre-harvest residue limit (PHRL) of abamectin (abamectin B1a and B1b) in Perilla frutescens leaves grown under greenhouse conditions were investigated using high-performance liquid chromatography with a fluorescence detector. Samples were extracted with acetonitrile. The extract was purified through a solid phase extraction procedure. Then the purified extract was derivatized with trifluoroacetic anhydride and N-methylimidazole to form a strong stable fluorescent derivative of abamectin. Finally, derivatized abamectins were conveyed to the detector via an Atlantis C18 column, with water and methanol as a mobile phase. Calibration curves were linear over the calibration ranges with coefficients of determinants r 2?≥?0.999. The limits of detection and quantification were 0.0033 and 0.01 mg kg?1 for abamectin B1a and B1b, respectively. Recovery was assessed in a control matrix at two different fortification concentrations, with three replicates for each concentration. Good recoveries were obtained for the target analytes and ranged from 82.11 to 93.03 %, with relative standard deviations of less than 8 %. The rate of disappearance of total abamectin on perilla leaves for recommended and double the recommended doses was described as first-order kinetics with a half-life of 0.7 days. Using the PHRL curve, we could predict the residue level of total abamectin to be 0.92 mg kg?1 at 7 days before harvest or 0.26 mg kg?1 at 4 days before harvest, which would be below the provisional MRL designed by the Korea Food and Drug Administration.  相似文献   
98.
Economists have shown the empirical relationships between the economic growth of a nation and its environmental quality using the hypothesis of the Environmental Kuznets Curve (EKC). To understand the EKC phenomena, a study of the literature was undertaken. As waste, waste emission, and suspended particulate matter (SPM) are the active agents of environmental degradation, the study focused on those agents for EKC consideration. Through understanding the different EKC trajectories, an attempt was made to relate the economic development of Bangladesh to the EKC. It is shown that the EKCs for waste, emissions from waste, and SPM follow the conventional EKC trajectory with a turning point related to higher income per capita in most cases. The type of economic policy that Bangladesh should follow to deal with the pollutants and their sources is also shown. The study recommends creating a tunnel in the EKC to lower the turning point in Bangladesh. The study is likely to help stimulate policy development in Bangladesh.  相似文献   
99.
Over the past decades, many Asian economies have achieved striking levels of economic growth. This economic growth has been necessary in order to fulfil the material needs and aspirations of growing populations. However, it has also been accompanied by substantial environmental degradation. While the precise interactions between economic growth, economic development and environmental degradation is subject to controversy and a comprehensive assessment of the Asian environment may be required to fully understand this relationship and the present conditions of the environment, it is argued in this paper that the achievement of sustainable economic development and the harmonizing of economic and environmental objectives will not be possible without deliberate policy interventions. Such policies need to incorporate a regional dimension in the form of institution building, in parallel to the concept of regional economic growth. The article focuses on the current problems of environmental and natural resource degradation in Asia, within a possible conceptual framework of impoverishing or unsustainable economic growth, and suggests a set of policies that need to be adopted in order to solve current difficulties.  相似文献   
100.
ABSTRACT: A model for estimating the probability of exceeding groundwater quality standards at environmental receptors based on a simple contaminant transport model is described. The model is intended for locations where knowledge about site-specific hydrogeologic conditions is limited. An efficient implementation methodology using numerical Monte Carlo simulation is presented. The uncertainty in the contaminant transport system due to uncertainty in the hydraulic conductivity is directly calculated in the Monte Carlo simulations. Numerous variations of the deterministic parameters of the model provide an indication of the change in exceedance probability with change in parameter value. The results of these variations for a generic example are presented in a concise graphical form which provides insight into the topology of the exceedance probability surface. This surface can be used to assess the impact of the various parameters on exceedance probability.  相似文献   
设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号