全文获取类型
收费全文 | 379篇 |
免费 | 41篇 |
国内免费 | 46篇 |
专业分类
安全科学 | 100篇 |
废物处理 | 20篇 |
环保管理 | 52篇 |
综合类 | 156篇 |
基础理论 | 65篇 |
污染及防治 | 32篇 |
评价与监测 | 8篇 |
社会与环境 | 8篇 |
灾害及防治 | 25篇 |
出版年
2024年 | 1篇 |
2023年 | 8篇 |
2022年 | 11篇 |
2021年 | 15篇 |
2020年 | 15篇 |
2019年 | 33篇 |
2018年 | 11篇 |
2017年 | 17篇 |
2016年 | 21篇 |
2015年 | 30篇 |
2014年 | 20篇 |
2013年 | 38篇 |
2012年 | 41篇 |
2011年 | 26篇 |
2010年 | 11篇 |
2009年 | 23篇 |
2008年 | 23篇 |
2007年 | 25篇 |
2006年 | 16篇 |
2005年 | 16篇 |
2004年 | 8篇 |
2003年 | 6篇 |
2002年 | 10篇 |
2001年 | 10篇 |
2000年 | 9篇 |
1999年 | 9篇 |
1998年 | 2篇 |
1997年 | 3篇 |
1996年 | 1篇 |
1994年 | 1篇 |
1993年 | 1篇 |
1991年 | 1篇 |
1983年 | 1篇 |
1982年 | 1篇 |
1981年 | 2篇 |
排序方式: 共有466条查询结果,搜索用时 15 毫秒
371.
Decamethylcyclopentasiloxane, commonly known as D5 (cyclopentasiloxane) has a wide application of use across a multitude of personal care product categories. The relative volatility of D5 is one of the key properties attributed to this substance that provide for the derived performance benefits from the use of this raw material in personal care formulations. On this basis, rapid evaporative loss following use of many products comprising D5 is expected following typical use application and corresponding wear time. 相似文献
372.
Mehmet Mahramanlioğlu İrfan Kizilcikli İ. Özlem Biçer Melda Tunçay 《Journal of environmental science and health. Part. B》2013,48(2):187-200
Abstract The removal of 2, 4‐D (2, 4‐ dichlorophenoxyacetic acid) from aqueous solutions by activated spent bleaching earths (SBE) was studied at 20 °C. Experiments were performed as a function of time, initial concentration, dose and particle size of the adsorbent. The Langmuir and Freundlich adsorption equations were fitted by the adsorption data obtained. The values of Langmuir and Freundlich constants were determined. The adsorption kinetic was found to follow Lagergren equation. Both the boundary layer and intraparticle diffusion played important roles in the adsorption rate of 2, 4‐D. As the size of the adsorbent increased, the time to reach equilibrium increased but adsorption capacity decreased. 相似文献
373.
374.
目前一般采用振动台试验、离心振动台试验和有限元动力分析来获得土石坝在设计地震荷载作用下的形态和抗震性能。本文结合孔宪京等的土石坝振动台试验结果开展了颗粒流细观数值模拟研究,克服了传统连续介质力学的宏观连续性假设,形象而直观地表现出坝体在动力荷载作用下的破坏特征。数值模拟规律与振动台试验规律基本一致。同时还分析了坝体颗粒粘结强度和地震峰值加速度变化对坝体破坏特征的影响。数值结果表明,当颗粒间粘结强度较低时,表现为坝体表面颗粒的滑动破坏,粘结强度稍大时,会出现局部的小块颗粒团整体滑动破坏;随着峰值加速度的增大,坝顶沉降量在增大,坝体破坏特征不变。 相似文献
375.
苏丹红Ⅰ、Ⅲ和Ⅳ对HepG-2细胞和SGC-7901细胞增殖的影响 总被引:4,自引:0,他引:4
以辽宁某地硼矿开采和加工厂的硼作业工人以及远离硼矿的背景地区的人群作为研究对象,分析了班后尿液硼浓度与日硼暴露剂量之间的关系.结果表明,班后尿硼浓度与日硼暴露剂量之间存在着显著的对数线性关系,考虑了不同人群类别的影响之后,回归方程的拟合度达到85.9%,由此确立了用班后尿硼浓度预测日硼暴露剂量的预测方程.用此预测方程对本研究2004年的受试者日硼暴露剂量进行预测,并与实测值进行了比较,结果表明平均相对偏差为13.4%,预测值与实测值之间没有显著性的差异.说明用班后尿硼浓度预测日硼暴露剂量是可行的.对2004年所有受试者的日硼暴露剂量预测结果分析表明,硼职业暴露组、社区对照组和背景对照组的日硼暴露剂量平均值分别为36.1、4.13和1.31mg/d. 相似文献
376.
为实现海洋平台落物风险快速精确评价,针对传统推荐性规范经验化、过于简化、平面化及未体现工程随机性等问题,以圆柱落物为研究对象开展先导研究,基于3D运动理论模型,提出1种采用Monte Carlo方法表征工程随机性以实现危险区快速精确评价的方法,自主开发形成海洋平台圆柱落物危险区快速评价工具(MREDP),着重分析落点分布规律和危险区等级划分。结果表明:落点分布整体呈现“倒工字圆弧型”、两端“一密一疏”、关于X轴对称特点;MREDP快速评价结果可信,评价周期大幅降低;MREDP快速评价危险区相对较大、存在多峰值点,DNVGL-RP-F107推荐危险区相对保守、存在单峰值点。 相似文献
377.
Solar geoengineering has received increasing attention as an option to temporarily stabilize global temperatures. A key concern is that heterogeneous preferences over the optimal amount of cooling combined with low deployment costs may allow the country with the strongest incentive for cooling, the so-called free-driver, to impose a substantial externality on the rest of the world. We analyze whether the threat of counter-geoengineering technologies capable of negating the climatic effects of solar geoengineering can overcome the free-driver problem and tilt the game in favour of international cooperation. Our game-theoretical model of countries with asymmetric preferences allows for a rigorous analysis of the strategic interaction surrounding solar geoengineering and counter-geoengineering. We find that counter-geoengineering prevents the free-driver outcome, but not always with benign effects. The presence of counter-geoengineering leads to either a climate clash where countries engage in a non-cooperative escalation of opposing climate interventions (negative welfare effect), a moratorium treaty where countries commit to abstain from either type of climate intervention (indeterminate welfare effect), or cooperative deployment of solar geoengineering (positive welfare effect). We show that the outcome depends crucially on the degree of asymmetry in temperature preferences between countries. 相似文献
378.
There is substantial variation in individual preferences for public goods, yet much of that variation remains poorly understood. However, simple measures of personality can help to explain economic values and choices in a systematic way. In this paper, we examine the effects of personality on individual economic choices over public environmental goods. Based on three datasets from three separate stated preference studies, we use a hybrid choice econometric framework to examine the effects of personality on preferences for the status quo, changes in environmental quality, and costs of investing in environmental improvements. We find effects that are consistent across all datasets. Personality, a stable feature of an individual's character that is simple to measure, enriches explanations of why the demand for environmental goods varies across people, provides an indication of how different people are likely to react to the introduction of environmental policies, and explains substantial differences in Willingness to Pay. 相似文献
379.
The performance assessment of safety barriers is essential to find vulnerable elements in a safety barrier system. Traditional performance assessment approaches mainly focus on using several static indicators for quantifying the performance of safety barriers. However, with the increasing complexity of the system, emerging hazards are highly uncertain, making it challenging for the static indicators to assess the performance of safety barriers. This paper proposes a resilience−based performance assessment method for safety barriers to overcome this problem. Safety barriers are classified according to their functions first. The dynamic Bayesian network (DBN) is then introduced to calculate the availability function under normal and disruption conditions. The ratio of the system's availability, when affected by the disruption, to the initial availability, is used to determine the absorption capacity of the system. The ratio of the quantity of availability recovery to the total quantity of system represents the adaptation and restoration capacity of the system. The system's resilience is represented by the sum of absorption, adaptation, and restoration capacities. The wax oil hydrogenation process is used to demonstrate the applicability of the proposed methodology. 相似文献