全文获取类型
收费全文 | 34951篇 |
免费 | 454篇 |
国内免费 | 722篇 |
专业分类
安全科学 | 1135篇 |
废物处理 | 1605篇 |
环保管理 | 4697篇 |
综合类 | 5437篇 |
基础理论 | 8986篇 |
环境理论 | 11篇 |
污染及防治 | 9347篇 |
评价与监测 | 2424篇 |
社会与环境 | 2220篇 |
灾害及防治 | 265篇 |
出版年
2023年 | 164篇 |
2022年 | 357篇 |
2021年 | 369篇 |
2020年 | 313篇 |
2019年 | 308篇 |
2018年 | 576篇 |
2017年 | 552篇 |
2016年 | 865篇 |
2015年 | 637篇 |
2014年 | 965篇 |
2013年 | 2941篇 |
2012年 | 1222篇 |
2011年 | 1639篇 |
2010年 | 1381篇 |
2009年 | 1427篇 |
2008年 | 1577篇 |
2007年 | 1706篇 |
2006年 | 1489篇 |
2005年 | 1239篇 |
2004年 | 1198篇 |
2003年 | 1165篇 |
2002年 | 1101篇 |
2001年 | 1409篇 |
2000年 | 1039篇 |
1999年 | 668篇 |
1998年 | 454篇 |
1997年 | 449篇 |
1996年 | 491篇 |
1995年 | 495篇 |
1994年 | 433篇 |
1993年 | 414篇 |
1992年 | 379篇 |
1991年 | 366篇 |
1990年 | 372篇 |
1989年 | 365篇 |
1988年 | 322篇 |
1987年 | 271篇 |
1986年 | 255篇 |
1985年 | 259篇 |
1984年 | 338篇 |
1983年 | 282篇 |
1982年 | 341篇 |
1981年 | 268篇 |
1980年 | 229篇 |
1979年 | 279篇 |
1978年 | 200篇 |
1977年 | 188篇 |
1976年 | 167篇 |
1975年 | 163篇 |
1974年 | 164篇 |
排序方式: 共有10000条查询结果,搜索用时 31 毫秒
1.
Carvalho Laíse M. Soares-Filho Antônio F. Lima Maciel S. Cruz-Filho João F. Dantas Taisa C. M. Luz Geraldo E. 《Environmental science and pollution research international》2021,28(7):7774-7785
Environmental Science and Pollution Research - A current environmental problem is the uncontrolled use of various pesticides that are harmful to the environment and public health. The herbicide... 相似文献
2.
Rudra P. Pradhan Mahendhiran S. Nair Mak B. Arvin John H. Hall 《Natural resources forum》2023,47(3):435-483
This article postulates strong endogenous relationships in lower income countries between institutional quality, financial development and sustained economic growth. These associations were investigated using the vector-error correction model (VECM) and Granger causality method for a sample of 79 countries from 2005 to 2022. The findings show that (1) these variables reinforce each other in the short run. (2) In the long run, both institutional quality and financial development can fuel economic growth. (3) The positive effect of institutional quality on economic growth is greater than that of financial development. Policy implications of these findings are that careful attention should be paid to co-development policies to enhance the institutional quality and the financial system in these economies. Policies should also consider economic growth strategies to enable sustainable economic growth rates. 相似文献
3.
The Science of Nature - We present the first study that compares phenological variation in parasite load and inflammatory response in a lizard with asynchronous male and female gonadal cycles.... 相似文献
4.
5.
Ismael A.S. Ehtiwesh Fernando Neto Da Silva Antonio C.M. Sousa 《International Journal of Green Energy》2019,16(1):72-85
The study addresses the potential of using concentrated solar power plants (CSPs) as a sustainable alternative of clean energy generation in the Mediterranean region and, in particular, in its North Africa shore. This location presents attractive conditions for the installation of CSPs, in particular high solar irradiation, good manpower concentration, and proximity and availability of water resources for condenser cooling. Energetic, exergetic, and economic analyses were conducted taking into consideration a particular type of CSPs - the parabolic trough concentrated solar power plant, which incorporates the most proven technology and it is already used in Southern Europe (Spain). In addition, the study considered the impact of project financing and incentives on the cost of energy. The combination of higher values for performance and potentially lower levelized cost of electricity (LCE) for the North Africa Mediterranean Rim than the South of Spain region can yield a very favorable return for the invested capital. Tripoli compared to Almeria presented superior performance and potentially lower LCE values ($0.18/kWh versus $0.22/kWh). This is significant, even when it is taken into consideration the fact that the plant in Tripoli, despite a relatively modest capacity factor of 34%, has a large gross power output of 173,886 MWhe. In addition, the implementation at the Tripoli location of a plant similar to the Anadsol plant has a slight advantage (2–3%) in terms of overall efficiency. 相似文献
6.
Conservation conflicts are gaining importance in contemporary conservation scholarship such that conservation may have entered a conflict hype. We attempted to uncover and deconstruct the normative assumptions behind such studies by raising several questions: what are conservation conflicts, what justifies the attention they receive, do conservation-conflict studies limit wildlife conservation, is scientific knowledge stacked against wildlife in conservation conflicts, do conservation-conflict studies adopt a specific view of democracy, can laws be used to force conservation outcomes, why is flexibility needed in managing conservation conflicts, can conservation conflicts be managed by promoting tolerance, and who needs to compromise in conservation conflicts? We suggest that many of the intellectual premises in the field may defang conservation and prevent it from truly addressing the current conservation crisis as it accelerates. By framing conservation conflicts as conflicts between people about wildlife or nature, the field insidiously transfers guilt, whereby human activities are no longer blamed for causing species decline and extinctions but conservation is instead blamed for causing social conflicts. When the focus is on mitigating social conflicts without limiting in any powerful way human activities damaging to nature, conservation-conflict studies risk keeping conservation within the limits of human activities, instead of keeping human activities within the limits of nature. For conservation to successfully stop the biodiversity crisis, we suggest the alternative goal of recognizing nature's right to existence to maintenance of ecological functions and evolutionary processes. Nature being a rights bearer or legal person would imply its needs must be explicitly taken into account in conflict adjudication. If, even in conservation, nature's interests come second to human interests, it may be no surprise that conservation cannot succeed. 相似文献
7.
8.
Baek Kitae Alessi Daniel S. Man Yu Bon Kwon Eilhann E. 《Environmental geochemistry and health》2021,43(9):3261-3262
Environmental Geochemistry and Health - 相似文献
9.
Chengyuan Gong Yi Yu Kaiqiang Wang Zhengkai Tu 《International Journal of Green Energy》2020,17(10):591-601
ABSTRACT In this study, a three-dimension (3D) computational model was proposed to investigate the flow and heat transfer characteristics of the intake grilles of two different fuel cell vehicles. The models of the intake grilles were constructed according to the actual sizes of two vehicles, namely, Roewe 950 and Toyota Mirai, considering the heat dissipation unit to simplify the heat transfer model of the vehicle. The results showed that relative to Roewe 950, Mirai intake air flow rate was approximately 10% higher, the heat transfer capacity was approximately 7% higher, and the intake grille area was larger. The coolant outlet temperature of Mirai was lower than that of Roewe 950, which was beneficial for the long term and stable operation of a fuel cell. This comparative study provided guidance for the intake grille and radiator design of fuel cell vehicles. The only difference between fuel cell vehicles on the market and conventional vehicles was that in the former, the internal combustion engine was replaced with a fuel cell stack, which had insufficient heat transfer capacity because of the reducing temperature difference. Increasing the intake grille area and the heat exchange capacity of the radiator were the key issues for the development of fuel cell vehicles. In this study, an optimal window opening angle of the radiator fin of 23° provided a maximal heat transfer coefficient. 相似文献
10.