全文获取类型
收费全文 | 177篇 |
免费 | 4篇 |
国内免费 | 2篇 |
专业分类
安全科学 | 7篇 |
废物处理 | 21篇 |
环保管理 | 15篇 |
综合类 | 11篇 |
基础理论 | 32篇 |
环境理论 | 1篇 |
污染及防治 | 41篇 |
评价与监测 | 34篇 |
社会与环境 | 20篇 |
灾害及防治 | 1篇 |
出版年
2023年 | 4篇 |
2022年 | 21篇 |
2021年 | 25篇 |
2020年 | 4篇 |
2019年 | 6篇 |
2018年 | 13篇 |
2017年 | 10篇 |
2016年 | 16篇 |
2015年 | 10篇 |
2014年 | 7篇 |
2013年 | 26篇 |
2012年 | 9篇 |
2011年 | 11篇 |
2010年 | 4篇 |
2009年 | 5篇 |
2008年 | 3篇 |
2007年 | 1篇 |
2006年 | 2篇 |
2005年 | 1篇 |
2004年 | 1篇 |
2002年 | 1篇 |
1989年 | 1篇 |
1986年 | 1篇 |
1985年 | 1篇 |
排序方式: 共有183条查询结果,搜索用时 15 毫秒
81.
Application of Artificial Neural Networks to Predict Total Dissolved Solids at the Karaj Dam 下载免费PDF全文
Gholamreza Asadollahfardi Hossein Zangooei Shiva Homayoun Aria Elnaz Danesh 《环境质量管理》2017,26(3):55-72
We applied multilayer perceptron (MLP) and radial basis function (RBF) neural networks using data from two water quality monitoring stations at the Karaj Dam in Iran. Input data were calcium ions (Ca2+), magnesium ions (Mg2+), sodium ions (Na+), chloride ions (Cl?), sulfate (), and pH, and the output data were total dissolved solids (TDS). An MLP with one hidden layer containing eight neurons was selected for the upstream water quality station using normalized input data. We developed a second MLP neural network for the downstream station with one hidden layer containing 10 neurons in the hidden layer using normalized input data. Considering applying normalized input data and one hidden layer, the coefficient of determination (R 2) and index of agreement (IA) between the observed and the predicted data for the upstream and downstream monitoring stations using the MLP neural networks were 0.985, 0.84, 0.99, and 0.92, respectively. The RBF neural network with 100 neurons in its hidden layer reached the minimum errors between the observed and the predicted results in upstream and downstream stations. The R 2 between observed and predicted data for upstream and downstream monitoring stations for the RBF was 0.999 and 0.998, respectively. Data normalization improved the performance of the MLP neural networks. Sensitivity analysis indicated that magnesium is the most effective water quality parameter for predicting TDS, and sulfate is the second most effective water quality parameter affecting TDS prediction at the Karaj Dam. 相似文献
82.
Hossein D. Atoufi Hasti Hasheminejad David J. Lampert 《Frontiers of Environmental Science & Engineering》2020,14(6):99
83.
Zare Sakhvidi MJ Bahrami A Ghiasvand A Mahjub H Tuduri L 《Environmental monitoring and assessment》2012,184(11):6483-6490
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
84.
Hossein Tabari Safar Marofi Mohammad Ahmadi 《Environmental monitoring and assessment》2011,177(1-4):273-287
Sixteen water quality parameters have been monitored at four stations located along the Maroon River during 1989?C2008. The trend analysis was performed on seasonal and annual time-scales using the Mann?CKendall test, the Sen??s slope estimator and the linear regression. The relationships of the water quality parameters to river discharge were also investigated. The statistical methods showed both positive and negative trends in annual water quality data. However, significant trends were detected by the statistical methods only in calcium, magnesium, sodium absorption ratio, pH, and turbidity series. The results indicated that the concentrations of the water quality parameters increased in spring and winter seasons, while the concentrations were diluted in summer and autumn seasons in the last two decades. Moreover, the highest numbers of significant trends were found in the spring and summer series, respectively. According to the regression analysis, most of the water quality parameters were negatively correlated with river discharge. 相似文献
85.
Hossein Ataei 《Journal of Material Cycles and Waste Management》2016,18(4):665-676
Sustainable development has become a major focus for engineers and planners as part of their collective efforts in finding, developing and integrating environmental-friendly solutions for material recycling and waste management into design and construction of civil engineering infrastructure. In the past three decades, there has been an increase in recycling and application of waste materials into the concrete to decrease costs and improve material properties of the concrete. Significant growth in automobile manufacturing industry and increased rubber tire supply for vehicles suggested the application of waste tire particles as concrete aggregates to minimize the ecological footprint of the rubber tire waste due to its recycling process difficulties. In this paper, the effect of rubber tire particles on compressive and dynamic strength of concrete specimens with different particle percentiles was tested on more than 55 cylindrical specimens. To achieve the optimal mix design properties of rubber tire concrete specimens, both fine and coarse aggregates got replaced by fine and coarse rubber particles. Introduction of rubber tire particles as coarse and fine aggregate reduces the brittleness of the concrete and provides more flexible aggregate bonding which ultimately improves the dynamic resistance of the concrete. It increases the concrete workability and provides environmental-friendly and cost-effective solutions in using recycled materials for concrete construction applications. 相似文献
86.
Hossein Faghihian Mozhgan Iravani Mohammad Moayed Mohammad Ghannadi-Maragheh 《Environmental Chemistry Letters》2013,11(3):277-282
Radioactive wastes containing Cs+ and Sr2+ are among the most dangerous environmental pollutants. Therefore, removing Cs+ and Sr2+ from environmental media is needed. Removal can be done by nanocrystalline ion exchangers. Nanocrystalline ion exchangers are studied in depth for the treatment of nuclear wastes because these exchangers have high exchange capacity and fast kinetics. However, operating the columns of these exchangers is very difficult. This issue may be overcome by the preparation and use of nanocomposites. Here, we prepared a novel polyacrylonitrile–zeolite nanocomposite for the removal of Cs+ and Sr2+ in a fixed-bed column operation. We studied the effect of influent flow rate, nanocomposite bed height and initial concentrations. Experimental data were analysed using the Thomas model and the bed-depth service time model. The results reveal that total adsorbed ion and bed capacity increased with increasing initial ions concentration and bed height; and decreased with increasing influent flow rate. The maximum bed capacity was 0.085 meq/g for Cs+ and 0.128 meq/g for Sr2+. The critical bed height (Z 0) was 4.35 cm for Cs+ and 2.89 cm for Sr2+. These findings demonstrate that the new nanocomposite is suitable for removal of Cs+ and Sr2+. 相似文献
87.
Mohamad Sadegh Ghasemi Payam Hosseinzadeh Farhad Zamani Hossein Ahmadpoor 《International journal of occupational safety and ergonomics》2013,19(4):519-523
Background. Work-related musculoskeletal disorders (WMSDs) are injuries and disorders that affect the body’s movement and musculoskeletal system. Awkward postures represent one of the major ergonomic risk factors that cause WMSDs among sonographers while working with an ultrasound transducer. This study aimed to design and evaluate a new holder for the ultrasound transducer. Materials and methods. In the first phase a new holder was designed for the transducer, considering design principles. Evaluation of the new holder was then carried out by electrogoniometry and a locally perceived discomfort (LPD) scale. Results. The application of design principles to the new holder resulted in an improvement of wrist posture and comfort. Wrist angles in extension, flexion, radial deviation and ulnar deviation were lower with utilization of the new holder. The severity of discomfort based on the LPD method in the two modes of work with and without the new holder was reported with values of 1.3 and 1.8, respectively (p?<?0.05). Conclusion. Overall, this study indicated that applying ergonomics design principles was effective in minimizing wrist deviation and increasing comfort while working with the new holder. 相似文献
88.
Mohammad Hossein Keshavarz Somayeh Moradi Ali Reza Madram Hamid Reza Pouretedal Karim Esmailpour Arash Shokrolahi 《Journal of Loss Prevention in the Process Industries》2013,26(4):650-659
This work presents a novel, reliable and simple method of estimating the flash point of various types of flammable amines, which are important for safety measures in industrial processes. Different amines include aliphatic amines such as primary, secondary, tertiary and cyclic amines as well as aromatic amines and hetero arenes containing nitrogen heteroatom. The proposed correlation is based on the contribution of some specific molecular moieties and functional groups, which can easily be used for any types of amines. Intermolecular forces are important in the new method, which are counted by two increasing and decreasing parameters. The root mean square (rms) deviation is 18 K for different classes of amines including 133 diverse compounds. The estimated flash points have been compared with one of the best available predictive methods, which gives much lower value of the rms deviation. 相似文献
89.
Nikseresht Ali Hajipour Bahman Pishva Nima Mohammadi Hossein Abbasian 《Environmental science and pollution research international》2022,29(28):42509-42538
Environmental Science and Pollution Research - Sustainable development emergent subfields have been rapidly evolving, and their popularity increased in recent years. Sustainable development is a... 相似文献
90.
Ghaffari Hamid Reza Farshidi Hossein Alipour Vali Dindarloo Kavoos Azad Mehdi Hassani Jamalidoust Marzieh Madani Abdolhossein Aghamolaei Teamour Hashemi Yaser Fazlzadeh Mehdi Fakhri Yadolah 《Environmental science and pollution research international》2022,29(57):85612-85618
Environmental Science and Pollution Research - There is ambiguity about the airborne transmission of the SARS-CoV-2. While a distance of 6 feet is considered a safe physical distance, new findings... 相似文献