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   140篇
  免费   1篇
  国内免费   5篇
安全科学   18篇
废物处理   15篇
环保管理   6篇
综合类   35篇
基础理论   12篇
污染及防治   29篇
评价与监测   16篇
社会与环境   14篇
灾害及防治   1篇
  2023年   8篇
  2022年   16篇
  2021年   20篇
  2020年   6篇
  2019年   10篇
  2018年   4篇
  2017年   9篇
  2016年   8篇
  2015年   5篇
  2014年   9篇
  2013年   18篇
  2012年   10篇
  2011年   5篇
  2010年   9篇
  2009年   5篇
  2006年   2篇
  2004年   2篇
排序方式: 共有146条查询结果,搜索用时 15 毫秒
71.
In order to achieve sustainable development in agriculture, it is necessary to quantify and compare the energy, economic, and environmental aspects of products. This paper studied the energy, economic, and greenhouse gas (GHG) emission patterns in broiler chicken farms in the Alborz province of Iran. We studied the effect of the broiler farm size as different production systems on the energy, economic, and environmental indices. Energy use efficiency (EUE) and benefit-cost ratio (BCR) were 0.16 and 1.11, respectively. Diesel fuel and feed contributed the most in total energy inputs, while feed and chicks were the most important inputs in economic analysis. GHG emission calculations showed that production of 1000 birds produces 19.13 t CO2-eq and feed had the highest share in total GHG emission. Total GHG emissions based on different functional units were 8.5 t CO2-eq per t of carcass and 6.83 kg CO2-eq per kg live weight. Results of farm size effect on EUE revealed that large farms had better energy management. For BCR, there was no significant difference between farms. Lower total GHG emissions were reported for large farms, caused by better management of inputs and fewer bird losses. Large farms with more investment had more efficient equipment, resulting in a decrease of the input consumption. In view of our study, it is recommended to support the small-scale broiler industry by providing subsidies to promote the use of high-efficiency equipment. To decrease the amount of energy usage and GHG emissions, replacing heaters (which use diesel fuel) with natural gas heaters can be considered. In addition to the above recommendations, the use of energy saving light bulbs may reduce broiler farm electricity consumption.  相似文献   
72.
Superior corporate environmental performance (CEP) has become essential to the competitive advantage and financial success of businesses. However, the main reasons managers pay attention to environmental performance are improved reputation in the capital market and profitability, as well as reductions in operating costs and risks. This article describes the findings of a study that examines the relationship between CEP, using a reduction of carbon dioxide (CO2) emissions as a measure, and corporate risk taking. In addition to indicating a significant negative relationship between CEP and firm risk, the study results also show that a 1% improvement of CEP decreases corporate risk by 3%.  相似文献   
73.
74.
Environment, Development and Sustainability - In this research, a new method to determine the supply chain performance based on its sustainable strategies is proposed. This method consists of a...  相似文献   
75.
Introduction. Based on the literature, the ergonomic saddle chair provides the most appropriate posture for users. Determination of the seat height is critical to establish the proper posture, carried out using various methods of anthropometry. This study aimed to develop a simple and applied method for determining the saddle seat height with an emphasis on appropriate posture. Methods. In this study, anthropometric dimensions including weight, body height, popliteal height and seat height at 135° knee angle in 150 male and female dentists were measured. In the laboratory, to determine the ‘acetabuloischial number’, 25 male and female natural hip bones were measured. The mean saddle-chair height with knee angle of 135° was then compared by two different methods, field measurement and the new calculation method. Results. The results showed a strong correlation between data gathered from the two different methods, the field measurement and the new calculation method (98%), and Cronbach’s α from the intraclass correlation was equal to 0.994 (p?<?0.05). This indicated that the two methods produced similar results. Conclusion. The new method can be applied to calculate the optimal height of the saddle seat based on body height and popliteal height.  相似文献   
76.
Occupational exposure to inhalational anesthetics occurs routinely in operating rooms. It could induce serious health hazards and diseases. This exposure assessment is a crucial step in determining risks. In this study, a pen-shaped holder for solid-phase microextraction (SPME) sampler was successfully applied as a time-weighted average sampling tool for workshift exposure assessment of operation room staff to halothane. It proved to be very convenient for use in occupational environments such as operation rooms. Samples were analyzed by a gas chromatography-mass spectrometry. The validity of the SPME method was checked in real-world conditions with Occupational Safety and Health Administration (OSHA) 103 standard method for the determination of inhalational anesthetics. A good agreement between OSHA 103 and SPME methods was obtained and results demonstrated no statistically significant differences in anesthetic concentrations determined by the two analytical methods (p?≥?0.05). It is concluded that SPME in retracted mode could successfully be applied in occupational exposure assessment purposes.  相似文献   
77.
Journal of Polymers and the Environment - Reactive Blue 19 (RB19) removal from synthetic textile wastewater was investigated by using a CoFe2O4@methylcellulose (MC) activated with peroxymonosulfate...  相似文献   
78.
Traditional and indigenous knowledge on plants usage is a valuable source of information from cultural and natural perspectives, reflecting society’s complicated and close relationship with the environment. Communities have a valuable source of traditional knowledge on the utilization of natural resources, and it is worth to be documented and preserved for current and future applications. We conducted this research to collect and identify plant species of Karvan District and document the traditional knowledge on their use and consumption values. Regarding the results, 150 plant species are used by local communities, more than 30 % of which are directly consumed as food, 24 % (37 species) are used as medicinal plants, and 16.3 % are applied for decoration purposes; 58.6 % of the species are consumed in the raw form, and the remaining is processed before consumption. Leaves (35 %), seeds (21 %) and flowers (21 %) are the most frequent parts of the plants that are used. High number of young emigrants to industrialized areas in seek of job opportunities is threatening this precious source of indigenous knowledge. Attempts to preserve this empirical source of information by encouraging trans-generational knowledge transmission would help to maintain it for future applications.  相似文献   
79.
80.
A principal component analysis (PCA) based methodology accounting for EHS hazard and sustainability metrics has been recently proposed in literature (Srinivasan and Nhan, 2008) to deal with the subjective weighting problem of existing index-based methods. In this study we evaluate the potential use of the PCA-based method during early phases of process design in the problem of selection between various synthesis paths, also called chemical routes, for the production of chemical compounds. The study also focuses on the impact of the methodology settings on the obtained chemical route rankings and their interpretation. Two case studies have been performed regarding the production of 4-(2-methoxyethyl)-phenol (MEP) and methyl methacrylate (MMA) using fifteen different evaluation categories capturing various sustainability metrics. The PCA-based method identified the most promising chemical routes as well as the most important evaluation categories. The necessity for normalization of the raw data was demonstrated, without the method being very sensitive to the type of normalization. Moreover, the effect of the transition approach from chemical step to chemical route scores is discussed. The results of the PCA-based method are also compared with an index-based method (Koller et al., 2000) sharing the same evaluation categories, as well as with other index-based frameworks in order to reveal the extent of similarities.  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