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   80篇
  免费   0篇
  国内免费   2篇
废物处理   3篇
环保管理   5篇
综合类   4篇
基础理论   22篇
污染及防治   30篇
评价与监测   12篇
社会与环境   5篇
灾害及防治   1篇
  2023年   1篇
  2022年   11篇
  2021年   3篇
  2020年   1篇
  2019年   4篇
  2018年   5篇
  2017年   2篇
  2016年   4篇
  2015年   5篇
  2014年   8篇
  2013年   12篇
  2012年   3篇
  2011年   6篇
  2008年   3篇
  2007年   6篇
  2004年   1篇
  2002年   2篇
  2000年   1篇
  1993年   1篇
  1991年   1篇
  1970年   1篇
  1964年   1篇
排序方式: 共有82条查询结果,搜索用时 31 毫秒
71.
A new optimal power flow model for wind, solar, and solar-thermal bundled power scheduling and dispatch is proposed, incorporating the deviation incentive/penalty charges for renewable energy introduced in India. The multiobjective function is solved using the flower pollination algorithm; the scheme is successfully tested on the IEEE 30-bus and Indian utility 30-bus systems. The forecasting error constraints introduced in renewable energy scheduling and dispatch are demonstrated to be beneficial in several aspects. Solar-thermal bundling is shown to create win-win situations for thermal and solar generators. The effectiveness of the flower pollination algorithm in solving optimal power flow models is proved.  相似文献   
72.

Purpose

There are many arguments on the carcinogenic potential of bitumen extract. The mechanism of bitumen-induced damage is not well understood at the molecular level. Therefore, in the present study, cell-transforming and tumor-inducing potential of bitumen extract was studied using in vitro [human osteosarcoma (HOS) cells] and in vivo [nude and severe combined immunodeficiency (SCID) mice] models.

Methods

Gas chromatography/mass spectrometry (GC/MS) analysis was carried out to find out the existence of carcinogenic compounds in the bitumen extract. Cell transformation test, anchorage independence assay, karyotyping assay, tumorigenicity assay, and 2-DE analysis were used to find out the effect of bitumen using the in vitro and in vivo models.

Results

GC/MS analysis showed the existence of carcinogenic compounds in the bitumen extract. HOS cells were treated with different concentrations (25, 50, and 100???l/ml) of bitumen extract. Compared to the parental HOS cells, bitumen transformants (HOS T1 and HOS T2) showed the characteristics of anchorage independency, chromosomal anomaly, and cellular transformation. Interestingly, bitumen transformants were not able to form tumor in nude/SCID mice. Proteomic analysis revealed the existence of 19 differentially expressed proteins involved in progression of cancer, angiogenesis, cell adhesion, etc.

Conclusions

Exposure of bitumen extract to HOS cells results in the cellular transformation similar to cancer cells and can modulate proteins involved in the progression of cancer. We state that the non-tumorogenic potential of bitumen transformant in nude/SCID mice can be attributed to the downregulation of galectin-1, chromodomain helicase DNA-binding protein 1-like gene, and membrane-associated guanylate kinase 2 protein.  相似文献   
73.
The main aim of this study is to investigate the combined effect of different operating parameters like adsorbent dose, initial Cr6+ concentration and pH on the removal of Cr6+ from aqueous solution using neem bark powder (NBP). A series of batch experiments were performed to find out the adsorption isotherms and kinetic behaviour of Cr6+ in the aqueous solution. The adsorption process was examined with three independent variables viz. NBP dosage, initial Cr6+ concentrations and pH. Seventeen batch experiments designed by Box–Behnken using response surface methodology were carried out, and the adsorption efficiency was modelled using polynomial equation as the function of the independent variables. Based on the uptake capacity and economic use of adsorbent, the independent variables were optimized by two procedures. The desirability of first and second optimization procedures were found to be 1.00 and 0.84, respectively, which shows that the estimated function may well represent the experimental model. The kinetic study indicated that the rate of adsorption confirms to the pseudo-second-order rate equation. Thermodynamics study indicated that the adsorption process was spontaneous and endothermic in nature. The surface texture changes in NBP were obtained from FT-IR analysis. The optimized result obtained from RAMP plots revealed that the NBP was supposed to be an effective and economically feasible adsorbent for the removal of Cr6+ from an aqueous system.  相似文献   
74.
There is a growing interest in management of MSW through micro-treatment of organic fraction of municipal solid wastes (OFMSW) in many cities of India. The OFMSW fraction is high (>80%) in many pockets within South Indian cities like Bangalore, Chikkamagalur, etc. and is largely represented by vegetable, fruit, packing and garden wastes. Among these, the last three have shown problems for easy decomposition. Fruit wastes are characterized by a large pectin supported fraction that decomposes quickly to organic acids (becomes pulpy) that eventually slow down anaerobic and aerobic decomposition processes. Paper fraction (newsprint and photocopying paper) as well as paddy straw (packing), bagasse (from cane juice stalls) and tree leaf litter (typical garden waste and street sweepings) are found in reasonably large proportions in MSW. These decompose slowly due to poor nutrients or physical state. We have examined the suitability of these substrates for micro-composting in plastic bins by tracking decomposition pattern and physical changes. It was found that fruit wastes decompose rapidly to produce organic acids and large leachate fraction such that it may need to be mixed with leachate absorbing materials (dry wastes) for good composting. Leaf litter, paddy straw and bagasse decompose to the tune of 90, 68 and 60% VS and are suitable for composting micro-treatment. Paper fractions even when augmented with 10% leaf compost failed to show appreciable decomposition in 50 days. All these feedstocks were found to have good biological methane potential (BMP) and showed promise for conversion to biogas under a mixed feed operation. Suitability of this approach was verified by operating a plug-flow type anaerobic digester where only leaf litter gathered nearby (as street sweepings) was used as feedstock. Here only a third of the BMP was realized at this scale (0.18 m3 biogas/kg VS 0.55 m3/kg in BMP). We conclude that anaerobic digestion in plug-flow like digesters appear a more suitable micro-treatment option (2–10 kg VS/day) because in addition to compost it also produces biogas for domestic use nearby.  相似文献   
75.
An experiment was conducted under laboratory conditions to investigate the effect of two systemic herbicides viz., pendimethalin and quizalofop, at their recommended field rates (1.0 kg and 50 g active ingredient ha − 1, respectively) on the growth and activities of non-symbiotic N2-fixing bacteria in relation to mineralization and availability of nitrogen in a Typic Haplustept soil. Both the herbicides, either singly or in a combination, stimulated the growth and activities of N2-fixing bacteria resulting in higher mineralization and availability of nitrogen in soil. The single application of quizalofop increased the proliferation of aerobic non-symbiotic N2-fixing bacteria to the highest extent while that of pendimethalin exerted maximum stimulation to their N2-fixing capacity in soil. Both the herbicides, either alone or in a combination, did not have any significant difference in the stimulation of total nitrogen content and availability of exchangeable NH4  +  while the solubility of NO3  −  was highly manifested when the herbicides were applied separately in soil.  相似文献   
76.
The present study is aimed at evaluating the genotype frequency of detoxifying genes such as GSTM1, GSTT1 and NQO1 in Maharastrian population of central India. The study revealed about 64.6% of GSTM1-positive and 35.4% GSTM1-null population. GSTT1-positive genotype was found to be 87.5% and GSTT1-null showed 12.5%. The NQO1 genotype of Maharastrian population showed 52.3% of C/C, 42.48% C/T and 5.18% T/T. The NQO1 of this population does not deviate from the expected Hardy-Weinberg equilibrium. The genotype frequencies GSTM1 and GSTT1 of the population when compared with other ethnic groups of Asia and Caucasians show distinct nature of Maharastrian population from other Asian and Caucasian population.  相似文献   
77.
78.
Environmental Science and Pollution Research - The fate of legacy and emerging flame retardants are poorly reported in developing countries, including India. Also, the positive matrix factorization...  相似文献   
79.
Environmental Science and Pollution Research - Nowadays, modern industries generate their energy by using renewable solar. The rapid increase in photovoltaic (PV) module installations provides a...  相似文献   
80.

Photovoltaic (PV) system produces electricity that differs from variations in environmental parameters such as temperature and solar radiation. The PV network will operate at maximum power point (MPP) and deal with an ever-increasing energy demand, that changes from both load and weather conditions.” Moreover, energy storage devices could be a potential solution for improving the efficiency and performance of renewable energy sources (RES). This paper intends to establish a control design by an optimization-assisted PI controller for a 7-level inverter. Accordingly, the gains of PI controller are adjusted dynamically by FireFly Integrated-Sea Lion Optimization algorithm (FFI-SLnO) that integrates the concepts of both Sea Lion Optimization (SLnO) and FireFly algorithm (FF). The gains should be tuned such that the error among the reference signal and fault signal should be low and hence better dynamic performance can be obtained by the presented optimized PI controller. Finally, the performance of the proposed method is compared over other traditional models with respect to certain measures and its superiority is proved.

  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