全文获取类型
收费全文 | 116篇 |
免费 | 2篇 |
国内免费 | 2篇 |
专业分类
安全科学 | 3篇 |
废物处理 | 5篇 |
环保管理 | 18篇 |
综合类 | 11篇 |
基础理论 | 24篇 |
污染及防治 | 40篇 |
评价与监测 | 14篇 |
社会与环境 | 5篇 |
出版年
2023年 | 6篇 |
2022年 | 14篇 |
2021年 | 10篇 |
2020年 | 1篇 |
2019年 | 3篇 |
2018年 | 6篇 |
2017年 | 8篇 |
2016年 | 8篇 |
2015年 | 2篇 |
2014年 | 3篇 |
2013年 | 10篇 |
2012年 | 5篇 |
2011年 | 5篇 |
2010年 | 1篇 |
2009年 | 3篇 |
2008年 | 2篇 |
2007年 | 7篇 |
2006年 | 6篇 |
2005年 | 2篇 |
2004年 | 1篇 |
2003年 | 1篇 |
2002年 | 3篇 |
2001年 | 1篇 |
2000年 | 1篇 |
1998年 | 2篇 |
1996年 | 1篇 |
1994年 | 1篇 |
1993年 | 1篇 |
1992年 | 1篇 |
1990年 | 1篇 |
1963年 | 1篇 |
1961年 | 1篇 |
1958年 | 1篇 |
1957年 | 1篇 |
排序方式: 共有120条查询结果,搜索用时 15 毫秒
41.
Karanja oil, containing 6.2% free fatty acids (FFAs), was considered for biodiesel production using a single-step solid-phase acid catalyzed process. Different types of zeolites and Amberlyst15 catalysts were tested and biodiesel was produced. Under similar conditions, the highest biodiesel yield was achieved using an Amberlyst15 catalyst, which contained 3–5% of moisture. The effects of operating parameters of the reaction such as reaction temperature, catalyst amount, and methanol-to-oil ratio were studied. An increase of methanol:oil ratio revealed a non-monotonic increase in biodiesel yields. Similar non-monotonic behavior was observed when Jatropha oil was used. Leaching and catalyst reusability were also considered. No significant effects of leaching were observed and catalyst reusability appeared to be affected by methanol interactions. The presence of a co-solvent, Tetrahydrofuran (THF), increased the biodiesel yield. Furthermore, an optimum amount of THF (THF:methanol volume ratio of 1:2) gave rise to the highest biodiesel yield. A biodiesel yield of 93% was achieved at 120 °C using a single-step process with Amberlyst15 as a catalyst, THF as a co-solvent, and a methanol:oil ratio of 30:1. 相似文献
42.
Das Basanta Kumar Roy Aparna Som Sukanya Chandra Ganesh Kumari Suman Sarkar Uttam Kumar Bhattacharjya Birendra Kumar Das Archan Kanti Pandit Arun 《Environmental science and pollution research international》2022,29(6):8452-8463
Environmental Science and Pollution Research - The COVID-19 pandemic has created unprecedented human health crisis in recent global history with rippling social and economic effects. The outbreak... 相似文献
43.
Present work investigates a noble approach toward the heat loss analysis of parabolic dish type solar cooker. Various experiments have been done on cooking pot to get the input parameter for calculation purposes. Cooking pot was kept at the focus of a parabolic dish type concentrator and repeated experiments have been done to measure solar radiation intensity (direct and Indirect) using a pyrometer, temperature at the focus of parabolic dish using a thermocouple and air velocity using hot wire anemometer to investigate the heat losses from the cooking pot. In the present article, a numerical approach has been performed to define the new parameter called performance index of the cooking pot which decides how the useful energy of working fluid inside the cooking pot approaches concentration ratio of the parabolic dish type solar cooker. The present analysis shows that the performance index varies from 15.45 to 17.66 and efficiency varies from 85.83% to 98.10% with the time of the day. 相似文献
44.
Internal combustion engines running on gaseous fuels produce low torque because the inducted gaseous fuel displaces air and reduces the volumetric efficiency. This can be overcome by injecting the gaseous fuel directly into the cylinder after the intake of air is completed. This work is a step in developing and demonstrating a cost effective system, as such systems are not readily available for small applications. A low-pressure gas injector was mounted on the cylinder barrel of a fully instrumented dual fuel engine. Its location is such that the injector will be exposed to the cylinder gases about 65.5 degrees before bottom dead center, where the cylinder pressure and temperature will be relatively low. An electronic controller was also developed to time the injection process to occur after the intake valve closes and also to control the duration of injection (quantity). Experiments were conducted with LPG (Liquefied petroleum gas) as the primary fuel that was injected with this new system and diesel as the pilot fuel at the rated speed of 1500 rpm with different amounts of LPG at 80% and 100% load. Comparisons of performance, combustion and emissions with the conventional manifold injection of LPG were done. The system allowed greater amounts of LPG to be used without knock as compared to manifold injection. On the whole the developed system has potential for application in small dual fuel and spark ignited gas engines and can be taken up for further optimization. 相似文献
45.
Arun Jayaseelan Nachiappan S. Rangarajan Goutham Alagappan Ram Prasath Gopinath K. P. Lichtfouse Eric 《Environmental Chemistry Letters》2023,21(1):339-362
Environmental Chemistry Letters - Global pollution is calling for advanced methods to remove contaminants from water and wastewater, such as TiO2-assisted photocatalysis. The... 相似文献
46.
Ecotourism's Support of Biodiversity Conservation 总被引:17,自引:0,他引:17
Marnie P. Bookbinder Eric Dinerstein Arun Rijal Hank Cauley & Arup Rajouria 《Conservation biology》1998,12(6):1399-1404
47.
Annamalai N Kumar A Saravanakumar A Vijaylakshmi S Balasubramanian T 《Journal of environmental biology / Academy of Environmental Biology, India》2011,32(6):781-786
Alcaligens faecalis AU01 isolated from seafood industry effluent produced an alkaline protease. The optimum culture conditions for growth as well as enzyme production were 37 degrees C and pH 8. The partially purified protease had specific activity of 9.66 with 17.77% recovery with the molecular weight of 33 kDa and it was active between 30-70 degrees C and optimum being at 55 degrees C and pH 9. The enzyme retains more than 85% activity at 70 degrees C and 78% even at pH 10. The enzyme inhibited the growth of fish pathogens such as Flavobacterium sp., Pseudomonas fluorescens, Vibrio harveyi, Proteus sp. and Vibrio parahaemolyticus. From the present study it can be concluded that Alcaligens faecalis AU01 has the potential for aquaculture as probiotic agent and other several applications. 相似文献
48.
Arsenic uptake by plants and possible phytoremediation applications: a brief overview 总被引:1,自引:0,他引:1
Meththika Vithanage Beata B. Dabrowska Arun B. Mukherjee Arifin Sandhi Prosun Bhattacharya 《Environmental Chemistry Letters》2012,10(3):217-224
This review focuses the behaviour of arsenic in plant?Csoil and plant?Cwater systems, arsenic?Cplant cell interactions, phytoremediation, and biosorption. Arsenate and arsenite uptake by plants varies in different environment conditions. An eco-friendly and low-cost method for arsenic removal from soil?Cwater system is phytoremediation, in which living plants are used to remove arsenic from the environment or to render it less toxic. Several factors such as soil redox conditions, arsenic speciation in soils, and the presence of phosphates play a major role. Translocation factor is the important feature for categorising plants for their remediation ability. Phytoremediation techniques often do not take into account the biosorption processes of living plants and plant litter. In biosorption techniques, contaminants can be removed by a biological substrate, as a sorbent, bacteria, fungi, algae, or vascular plants surfaces based on passive binding of arsenic or other contaminants on cell wall surfaces containing special active functional groups. Evaluation of the current literature suggests that understanding molecular level processes, and kinetic aspects in phytoremediation using advanced analytical techniques are essential for designing phytoremediation technologies with improved, predictable remedial success. Hence, more efforts are needed on addressing the molecular level behaviour of arsenic in plants, kinetics of uptake, and transfer of arsenic in plants with flowing waters, remobilisation through decay, possible methylation, and volatilisation. 相似文献
49.
Munmun Chakarvorty Jayanta Kumar Pati Shiva Kumar Patil Swati Shukla Ambalika Niyogi Arun Kumar Saraf 《Environmental monitoring and assessment》2014,186(5):2965-2978
The winter fog in India is a recurrent phenomenon for more than a decade now affecting the entire Himalayan and sub-Himalayan regions covering an area of nearly 500,000 km2. Every winter (December–January), the air and surface transports in cities of northern India (Amritsar, New Delhi, Agra, Gwalior, Kanpur, Lucknow, and Allahabad) are severely disrupted with visibility reduced to <50 m at times. Since dust particles are known to act as nuclei for the fog formation, this study is aimed to carry out physicochemical characterization of the dust particulates accumulated during a protracted fog period from one of the severely fog affected cities of north India (Allahabad; 25°27′33.40″N–81°52′45.47″E). The dust-loaded tree leaves belonging to Ficus bengalensis and Ficus religiosa from 50 different locations between January 24 and 31, 2010 are sampled and characterized. The mass of dust, color, grain shape, size, phase constituents, and mineral magnetic parameters, such as magnetic susceptibility, SIRM, χ fd%, and S-ratio, show minor variation and the regional influence outweighs local anthropogenic contributions. The dust compositions show fractionated rare earth element pattern with a pronounced negative Eu anomaly similar to upper continental crust and further suggesting their derivation from sources located in parts of north and central India. 相似文献
50.
Das Ananya Baig Nisar Ali Yawar Mohammad Kumar Arun Habib Gazala Perumal Vivekanandan 《Environmental science and pollution research international》2023,30(5):11600-11616
Environmental Science and Pollution Research - Delhi has been identified as one of the highly polluted cities in the world and recently associated with the highest population weighted PM2.5... 相似文献