全文获取类型
收费全文 | 257篇 |
免费 | 30篇 |
国内免费 | 126篇 |
专业分类
安全科学 | 43篇 |
废物处理 | 34篇 |
环保管理 | 35篇 |
综合类 | 190篇 |
基础理论 | 28篇 |
污染及防治 | 77篇 |
评价与监测 | 2篇 |
社会与环境 | 3篇 |
灾害及防治 | 1篇 |
出版年
2023年 | 4篇 |
2022年 | 9篇 |
2021年 | 14篇 |
2020年 | 11篇 |
2019年 | 5篇 |
2018年 | 16篇 |
2017年 | 13篇 |
2016年 | 24篇 |
2015年 | 21篇 |
2014年 | 15篇 |
2013年 | 34篇 |
2012年 | 30篇 |
2011年 | 26篇 |
2010年 | 23篇 |
2009年 | 33篇 |
2008年 | 13篇 |
2007年 | 17篇 |
2006年 | 28篇 |
2005年 | 17篇 |
2004年 | 14篇 |
2003年 | 9篇 |
2002年 | 11篇 |
2001年 | 4篇 |
2000年 | 6篇 |
1999年 | 7篇 |
1998年 | 5篇 |
1997年 | 1篇 |
1996年 | 1篇 |
1995年 | 2篇 |
排序方式: 共有413条查询结果,搜索用时 21 毫秒
121.
废印制线路板真空热解产物分析 总被引:1,自引:0,他引:1
在自行设计的间歇式固定床真空热解装置中热解废印制线路板(PCB),对热解产物进行了分析.在热解温度为550 ℃、热解压力为20 kPa、恒温时间为60 min的条件下,得到的热解产物质量分数为:热解渣70%;热解油3%~4%;不可冷凝热解气26%~27%.经气相色谱-质谱联用(GC-MS)分析,热解油经常压蒸馏后得到的低沸点液态油中含有29种化合物,主要有苯酚、对异丙基酚、3-乙基酚、4-甲酚及2-溴苯酚,还含有少量含溴化合物和含氯化合物.热解油经简单的蒸馏就可达到回收酚类化合物的目的.热解渣经风选可实现铜与黏附有碳黑的玻璃纤维的分离,其中铜质量分数约30%,黏附有碳黑的玻璃纤维质量分数约70%. 相似文献
122.
123.
124.
热解温度和时间对生物干化污泥生物炭性质的影响 总被引:5,自引:0,他引:5
污泥热解制备生物炭是一种很有潜力的污泥资源化处置方式,然而,生物炭产量和品质因污泥原料性质、热解条件(如热解温度、时间)的不同而存在显著差异。以生物干化污泥为主要研究对象,系统考察了热解温度及时间等热解因素对生物炭品质的影响。实验结果表明,随着热解温度的升高(300~700℃),热解时间的增加(2~4 h),生物炭产率均下降。低温热解(300℃)生物炭,偏酸性,而高温热解时(700℃)生物炭,偏碱性。生物炭N含量随着热解温度的升高、热解时间的增加而降低,而P、K及微量元素随着热解温度的升高,热解时间的增加而增加。DTPA浸提结果表明,高温热解明显降低了生物炭中微量元素的生物有效性。 相似文献
125.
Combustion of Tyre Pyrolysis Oil 总被引:6,自引:0,他引:6
P.T. Williams R.P. Bottrill A.M. Cunliffe 《Process Safety and Environmental Protection》1998,76(4):291-301
126.
废聚苯乙烯的化学回收方法 总被引:10,自引:0,他引:10
废聚乙烯(PS)转化为燃料油和化学品的化学回收方法,分为废PS单独裂解及废PS与其它废塑料混合裂解两种方式,分别阐述了两种回收方式的研究成果和工艺现状,并就存在的问题进行了讨论。 相似文献
127.
城市生活垃圾在热解处理中的产气特性研究 总被引:7,自引:0,他引:7
通过对沈阳市皇姑区内的3个垃圾排放点进行实地采样并分类称量,得出其组分含量,得到了生活垃圾的主要物料组份.在此基础上在外加热固定床式热解试验台上,用热解实验的方法对8种城市生活垃圾中的主要物料中的典型成分进行热解试验.通过数据分析总结出不同工况下产气特性和热解气体的组分含量、热值,并建立热解气体析出模型进行产气量预测. 相似文献
128.
Jyothunaik Ramavathu Thirupathi Reddy Kota 《International Journal of Sustainable Engineering》2020,13(3):204-217
ABSTRACT Analysis of plastic oil obtained from waste plastic through pyrolysis process, as an alternative to biodiesel is presented in this paper. The HCCI engine is considered for experimental validation of combustion performance and emission characteristics. To accumulate pyrolysis oil as fuel, the design modifications were made in external mixture formation on the existing computerised 4-stroke, single cylinder, water cooled, direct injection kirloskar diesel engine connected with eddy current dynamometer to satisfy HCCI conditions. HCCI engine can be worked on wide assortment of fuels beginning from diesel to different blends (WPPO 5%,10%,15% and 20% by volume) of biodiesel .The designed additional device connected to the engine is utilised for fuel vaporisation and mixture arrangement. In the experimental study, the combustion results were initiate to be of 39.69 % higher Rate of Heat Release (RoHR) for biodiesel HCCI as compared with diesel HCCI. Higher brake thermal efficiency (BTE) was found 37 % without exhaust gas recirculation (EGR) at WPPO 20 % biodiesel blend. And also found 50 % and 65 % reduction in NOx emission and 18 % and 28 % reduction in smoke opacity are obtained for biodiesel vapour induction without EGR and biodiesel vapour induction with 15 % EGR as compared with diesel fuel. The CO (0.34 %), and UHC (2.15 %) emissions are increases with 15 % EGR, but the emissions are within the standard limits specified by the emissions standards. 相似文献
129.
Tyre recycling has become a necessity because of the huge piles of tyres that represent a threat to the environment. The used
tyres represent a source of energy and valuable chemical products. Waste tyres were pyrolysed catalytically in a batch reactor
under atmospheric pressure. Calcium carbide was used as a catalyst to explore its effect on pyrolysis product distribution.
The effect of temperature, amount of catalyst and time on the yields of the pyrolysed products was investigated. Char yield
decreased with increase of pyrolysis temperature while total gas and liquid yields increased. The liquid fraction was obtained
with boiling point up to 320 °C. The physical and chemical properties of the pyrolysed products obtained were characterized.
The catalytic pyrolysis produced 45 wt.% aromatic, 35 wt.% aliphatic and 20 wt.% of polar hydrocarbons.
The distillation data showed that ∼80% of oil has boiling point below 270 °C which is the boiling point for 50% of distilled
product in commercial diesel oil. The oil fraction was found to have high gross calorific value; GCV (42.8 MJ kg−1). Its Specific gravity, viscosity, Kinematic viscosity, freezing point and diesel index were also within the limits of diesel
fuel.
The char residues were studied to investigate their characteristics for use as a possible adsorbent. Surface area of char
before and after acid demineralization was determined to determine the adsorptive features for waste water treatment. 相似文献
130.