全文获取类型
收费全文 | 1200篇 |
免费 | 95篇 |
国内免费 | 307篇 |
专业分类
安全科学 | 124篇 |
废物处理 | 72篇 |
环保管理 | 137篇 |
综合类 | 586篇 |
基础理论 | 216篇 |
环境理论 | 1篇 |
污染及防治 | 298篇 |
评价与监测 | 63篇 |
社会与环境 | 57篇 |
灾害及防治 | 48篇 |
出版年
2024年 | 5篇 |
2023年 | 40篇 |
2022年 | 70篇 |
2021年 | 66篇 |
2020年 | 62篇 |
2019年 | 47篇 |
2018年 | 66篇 |
2017年 | 63篇 |
2016年 | 68篇 |
2015年 | 70篇 |
2014年 | 93篇 |
2013年 | 112篇 |
2012年 | 85篇 |
2011年 | 94篇 |
2010年 | 81篇 |
2009年 | 93篇 |
2008年 | 55篇 |
2007年 | 61篇 |
2006年 | 50篇 |
2005年 | 52篇 |
2004年 | 36篇 |
2003年 | 35篇 |
2002年 | 35篇 |
2001年 | 25篇 |
2000年 | 26篇 |
1999年 | 15篇 |
1998年 | 5篇 |
1997年 | 9篇 |
1996年 | 10篇 |
1995年 | 9篇 |
1994年 | 9篇 |
1993年 | 9篇 |
1992年 | 9篇 |
1991年 | 5篇 |
1990年 | 7篇 |
1989年 | 3篇 |
1988年 | 2篇 |
1987年 | 2篇 |
1986年 | 2篇 |
1984年 | 1篇 |
1983年 | 1篇 |
1982年 | 2篇 |
1981年 | 1篇 |
1980年 | 2篇 |
1979年 | 1篇 |
1978年 | 3篇 |
1975年 | 1篇 |
1972年 | 1篇 |
1970年 | 1篇 |
1968年 | 1篇 |
排序方式: 共有1602条查询结果,搜索用时 0 毫秒
991.
Qunan Wang Xin Xi Xiaomei Deng Nian Li Daji Wu Long Zhang Chengwei Yang Fangbiao Tao Jiangning Zhou 《环境科学学报(英文版)》2016,28(3):252-260
Lambda-cyhalothrin(LCT),one of the type II pyrethroids,has been widely used throughout the world.The estrogenic effect of LCT to increase cell proliferation has been well established.However,whether the estrogenic effect of LCT will influence neurodevelopment has not been investigated.In addition,17β-Estradiol(E2)plays a crucial role in neurodevelopment and induces an increase in synaptic proteins.The post-synaptic density 95(PSD95)protein,which is involved in the development of the structure and function of new spines and localized with estrogen receptor α(ERα)at the post-synaptic density(PSD),was detected in our study by using hippocampal neuron cell line HT22.We found that LCT up-regulated PSD95 and ERα expression,estrogen receptor(ER)antagonist ICI182,780 and phosphatidylinositol-4;5-bisphosphate 3-kinase(PI3K)inhibitor LY294,002 blocked this effect.In addition,LCT disrupted the promotion effect of E2 on PSD95.To investigate whether the observed changes are caused by ERα-dependent signaling activation,we next detected the effects of LCT on the ERα-mediated PI3K-Protein kinase B(PKB/Akt)-eukaryotic initiation factor(e IF)4E-binding protein 1(4E-BP1)pathway.There existed an activation of Akt and the downstream factor 4E-BP1 after LCT treatment.In addition,LCT could disrupt the activation effect of E2 on the Akt pathway.However,no changes in c AMP response element-binding protein(CREB)activation and PSD95 messenger ribonucleic acid(m RNA)were observed.Our findings demonstrated that LCT could increase the PSD95 protein level via the ERα-dependent Akt pathway,and LCT might disrupt the up-regulation effect of E2 on PSD95 protein expression via this signaling pathway. 相似文献
992.
基于2016—2018年安徽省68个国控环境空气质量自动监测站点的臭氧(O3)监测数据,研究分析了安徽省O3污染特征及其与气象因子的相关性。结果表明:安徽省O3污染程度呈现逐年加重趋势,并有显著的季节和月度变化特征。2016—2018年,各年度单月O3日最大8小时滑动平均质量浓度第90百分位数的最大值分别出现在9月、5月、6月。O3日变化趋势为典型的单峰形,各年度最低值出现在晨间07:00左右,最高值则是在15:00—16:00。全省O3浓度总体上呈现出北高南低的空间特征。温度、相对湿度与O3浓度分别呈现显著正相关、负相关,但在不同季节存在一定差异,其中,春秋季温度与O3浓度的相关性好于夏冬季,夏季相对湿度与O3浓度的相关性最为显著。O3浓度在平均风速为2.1~2.2 m/s时更易出现超标。中部和北部城市在东南风的作用下易出现O3超标并达到O 相似文献
993.
994.
腐殖酸作用下沉积物中纳米氧化铜对铜锈环棱螺生态毒性的影响 总被引:1,自引:0,他引:1
为了探讨不同水平腐殖酸作用下沉积物中纳米氧化铜(CuO-NPs)对底栖生物生态毒理学效应的影响,以铜锈环棱螺(Bellamya aeruginosa)为受试生物,通过腐殖酸和CuO-NPs加标沉积物的慢性(28 d)生物测试,研究了肝胰脏中Cu的生物积累、Na+K+-ATP酶(ATPase)、超氧化物歧化酶(SOD)以及过氧化氢酶(CAT)活性的变化规律.结果表明,在低浓度CuO-NPs处理组(60 μg·g1),沉积物中腐殖酸水平对Cu的生物积累以及ATPase、SOD和CAT活性均没有显著影响.在中、高浓度CuO-NPs处理组(≥180 μg·g-1),Cu的生物积累均随腐殖酸水平的增加而显著升高;肝胰脏ATPase活性随腐殖酸水平的增加而显著下降;当腐殖酸水平为0.05 g·g-1时,SOD活性显著高于未添加腐殖酸组,表现为显著诱导,当腐殖酸水平≥0.1g·g-1时,SOD活性开始下降,并具有浓度依赖性;随腐殖酸水平的增加,肝胰脏CAT活性总体上表现为浓度依赖性显著下降.由于沉积物中腐殖酸的存在,显著增加CuO-NPs在沉积物中的分散稳定性,更容易被铜锈环棱螺摄取,从而通过增加CuO-NPs的生物积累而增强对铜锈环棱螺的生态毒性. 相似文献
995.
996.
小麦/玉米和蚕豆/玉米间作对土壤硝态氮累积和氮素利用效率的影响 总被引:8,自引:0,他引:8
提高氮肥利用效率,减少氮肥过量施用对环境造成的污染,是保障国家粮食生产和生态环境安全的关键.文章以甘肃河西灌区为试验地点,在0、300、450 kg·hm-2氮水平下,探讨了小麦(Triticum aestivum L.)/玉米(Zea mays L.)和蚕豆(Vicia faba L.)/玉米间作对土壤硝态氮累积和分布的影响.结果表明:随氮肥用量增加,0~60 cm土层土壤硝态氮相对累积量增加,100~200 cm土层降低.在3个氮水平下,蚕豆间作土壤硝态氮含量和累积量都低于单作.小麦间作在300 kg·hm-2氮水平下土壤硝态氮累积量都低于单作,但在0和450 kg·hm-2氮水平下,小麦收获后间作与单作近似,玉米收获后小麦间作土壤硝态氮累积量都低于单作.与小麦和蚕豆间作的玉米在300 kg·hm-2氮水平下土壤硝态氮累积量都低于单作玉米,在0和450 kg·hm-2氮水平下则表现不同.在300 kg·hm-2氮水平下,两种间作氮肥当季利用率都明显高于相应的单作,施氮量增加到450 kg·hm-2时,则表现不一样. 相似文献
997.
Oukarroum A Polchtchikov S Perreault F Popovic R 《Environmental science and pollution research international》2012,19(5):1755-1762
Purpose
In this study, the effect of silver nanoparticles (AgNPs) on the photosynthetic performance of two green algae, Chlorella vulgaris and Dunaliella tertiolecta, was investigated at 25°C and 31°C.Methods
To induce AgNPs effect, algal cells were exposed for 24?h to concentrations varying from 0 to 10?mg/L. The polyphasic OJIP fluorescence transient was used to evaluate photosystem II (PSII).Results
We show that growth media and temperature had different effects in AgNPs agglomerates formation and Zeta potential. When temperature conditions change, inhibitory effect of AgNPs also undergoes changes. Increase of temperature induced higher altering effects to PSII quantum yield, primary photosynthetic electron transport, and consequently higher decrease of total photosynthetic performance if compared to AgNPs effect alone. AgNPs has a negative effect on D. tertiolecta compared to C. vulgaris.Conclusion
We conclude that temperature tends to enhance the toxic effects on aquatic alga and these alterations might have serious consequences on ecosystem equilibrium and aquatic plant communities. 相似文献998.
Erin L. Murphy Miranda Bernard Gwenllian Iacona Stephanie B. Borrelle Megan Barnes Alexis McGivern Jorge Emmanuel Leah R. Gerber 《Conservation biology》2022,36(2):e13827
Marine plastic pollution has emerged as one of the most pressing environmental challenges of our time. Although there has been a surge in global investment for implementing interventions to mitigate plastic pollution, there has been little attention given to the cost of these interventions. We developed a decision support framework to identify the economic, social, and ecological costs and benefits of plastic pollution interventions for different sectors and stakeholders. We calculated net cost as a function of six cost and benefit categories with the following equation: cost of implementing an intervention (direct, indirect, and nonmonetary costs) minus recovered costs and benefits (monetary and nonmonetary) produced by the interventions. We applied our framework to two quantitative case studies (a solid waste management plan and a trash interceptor) and four comparative case studies, evaluating the costs of beach cleanups and waste-to-energy plants in various contexts, to identify factors that influence the costs of plastic pollution interventions. The socioeconomic context of implementation, the spatial scale of implementation, and the time scale of evaluation all influence costs and the distribution of costs across stakeholders. Our framework provides an approach to estimate and compare the costs of a range of interventions across sociopolitical and economic contexts. 相似文献
999.
1000.
Although Africa has many threatened species and biological hot spots, there are few citizen science schemes, particularly in rural communities, and there has been limited evaluation of existing programs. We engaged traditional Maasai warriors (pastoralist men aged 15 to 35) in community‐based conservation and demographic monitoring of a persecuted African lion (Panthera leo) population. Through direct engagement, we investigated whether a citizen science approach employing local warriors, who had no formal education, could produce reliable data on the demographics, predation, and movements of a species with which their communities have been in conflict for generations. Warriors were given benefits such as literacy training and skill enhancement and engaged in the monitoring of the lions. The trained warriors reported on lion sign across an area nearly 4000 km2. Scientists worked together with the warriors to verify their reports and gather observations on the lion population. Using the verified reports and collected observations, we examined our scientific knowledge relative to the lion population preceding and during the citizen science program. Our observations showed that data quality and quantity improved with the involvement and training of the participants. Furthermore, because they engaged in conservation and gained personal benefits, the participants came to appreciate a species that was traditionally their foe. We believe engaging other local communities in biodiversity conservation and monitoring may be an effective conservation approach in rural Africa. 相似文献