全文获取类型
收费全文 | 1270篇 |
免费 | 110篇 |
国内免费 | 877篇 |
专业分类
安全科学 | 64篇 |
废物处理 | 17篇 |
环保管理 | 86篇 |
综合类 | 830篇 |
基础理论 | 848篇 |
污染及防治 | 282篇 |
评价与监测 | 99篇 |
社会与环境 | 30篇 |
灾害及防治 | 1篇 |
出版年
2023年 | 10篇 |
2022年 | 34篇 |
2021年 | 39篇 |
2020年 | 38篇 |
2019年 | 63篇 |
2018年 | 62篇 |
2017年 | 94篇 |
2016年 | 85篇 |
2015年 | 118篇 |
2014年 | 103篇 |
2013年 | 287篇 |
2012年 | 143篇 |
2011年 | 136篇 |
2010年 | 87篇 |
2009年 | 111篇 |
2008年 | 74篇 |
2007年 | 101篇 |
2006年 | 97篇 |
2005年 | 78篇 |
2004年 | 63篇 |
2003年 | 69篇 |
2002年 | 42篇 |
2001年 | 49篇 |
2000年 | 39篇 |
1999年 | 26篇 |
1998年 | 45篇 |
1997年 | 33篇 |
1996年 | 20篇 |
1995年 | 27篇 |
1994年 | 29篇 |
1993年 | 17篇 |
1992年 | 8篇 |
1991年 | 4篇 |
1990年 | 3篇 |
1989年 | 1篇 |
1988年 | 2篇 |
1987年 | 2篇 |
1986年 | 3篇 |
1985年 | 1篇 |
1984年 | 1篇 |
1983年 | 4篇 |
1981年 | 2篇 |
1980年 | 1篇 |
1979年 | 2篇 |
1978年 | 2篇 |
1977年 | 1篇 |
1975年 | 1篇 |
排序方式: 共有2257条查询结果,搜索用时 15 毫秒
931.
用水生生物对重金属污染土壤进行生态毒理评价 总被引:1,自引:0,他引:1
应用斜生栅藻(Scenedesmus obliquus)和明亮发光杆菌T3(Photobacterium phosphoreum)急性毒性实验方法对重金属污染土壤的进行生态毒理评价,结果表明,斜生栅藻的生长繁殖率和发光菌的相对发光度与土壤中的重金属含量明显相关,并且随重金属投加量的增加,其生长繁殖率和发光度逐渐降低。对3种测试参数进行比较可知,斜生栅藻细胞数增长率是最敏感的土壤毒性检测指标。土壤的毒性在复合污染的条件下比在单一污染的条件下高很多。本研究的结果可以为污染土壤的优先修复提供理论依据。 相似文献
932.
Uptake and Modeling of Pesticides by Roots and Shoots of Parrotfeather (Myriophyllum aquaticum) (5 pp) 总被引:1,自引:0,他引:1
Turgut C 《Environmental science and pollution research international》2005,12(6):342-346
Intention, Goal, Scope, Background Aquatic plants have a great potential to function as in situ, on-site biosinks and biofilters of pollutants. They are used
for phytoremediation and phytotoxicity studies. Pesticide uptake studies are very important to predict contaminant accumulation,
translocation, and transformation. There are a lot of models which have been developed for emergent plants, but there are
not any existing models for submerged aquatic plants for assessing pesticide uptake.
Objective In this study, uptake of selected pesticides in parrotfeather (Myriophyllum aquaticum) were studied and the results were
modeled with the aid of Log Kow and the concentration of pesticides. At the end, the developed model was compared to other
existing models.
Methods The test was conducted with parrotfeather as a model plant. The bioassay and cultivation of this plant were examined. Pesticide
uptake by roots and shoots was determined using 14C-radiolabeled materials.
Results and Discussion The results were fitted with an equation that showed a relationship between uptake and lipophilicity of pesticides. The model
was compared with other pesticide uptake models developed for other plants. Atrazine and cycloxidim were taken up more by
roots than by shoots in comparison to other pesticides used. The total uptake, both in shoots and roots, was lower than for
terbutryn and trifluralin. The best appropriate model was developed from the results against the other models seen in the
literature. The concentration factors (Root Concentration Factor (RCF) and Submerged Shoot Concentration Factor (SSCF)) increased
with a higher Kow of the substances. The Submerged Shoot Concentration Factor (SSCF) revealed a better relationship of the
chemicals than did the Root Concentration Factor (RCF).
Conclusions In this study, an uptake model was developed for rooted, submerged aquatic plants. Further studies are necessary to develop
and compare models with different plants and pesticides.
Recommendation and Outlook Such studies as this one may be extended to other environmental pollutants in the aquatic ecosystem and may be employed to
evaluate the possibility of using different plants in phytoremediation studies. 相似文献
933.
Effects of atrazine on acetylcholinesterase activity in midges (Chironomus tentans) exposed to organophosphorus insecticides 总被引:2,自引:0,他引:2
Acetylcholinesterase activity was determined for midge larvae (Chironomus tentans) exposed to either organophosphorus insecticides (OPs) alone or OP insecticides in binary combination with atrazine (200 μg/l). Although atrazine by itself did not reduce the level of acetylcholinesterase activity, atrazine in combination with chlorpyrifos significantly decreased acetylcholinesterase activity as compared to chlorpyrifos only treatments. Although similar trends existed for malathion and methyl parathion, differences were not statistically significant. These results match previously published toxicity data where atrazine, although not acutely toxic even at much higher levels, decreased EC50 values for chlorpyrifos by a magnitude of 4, decreased methyl parathion values by a magnitude of 2, and did not decrease values for malathion. 相似文献
934.
山苍籽油抗霉作用研究 总被引:4,自引:1,他引:4
用减压蒸馏法从山苍籽[Litseacubeba(Lour)Per]提取天然植物精油.以熏蒸和喷洒等方式进行对档案资料、图书的防霉实验.结果表明山苍籽油具有显著的防霉功效,防霉的广谱性和高效性优于目前市售产品.该植物精油对纤维素和少量半纤维素、木质素纸张耐折度.抗老化及字迹颜色坚牢度试验.表明对纸张和字迹无显著影响;毒理分析表明属于安全低毒抗霉剂 相似文献
935.
乐安江水和沉积物样品的生物毒性评估 总被引:17,自引:0,他引:17
采用二种发光菌发光抑制、二种藻生长抑制、大型溲生和慢性毒性多种生物测试方法。对采集于1993年6月,1993年12月和199410月的乐安江可水、沉积物和沉积物间隙不进行了多指标生物毒性测试,在河流40,50和159km处观测到较强毒性,研究结果:毒性排放主要来自乐安江上游德兴铜矿、洎不河,以及乐安江下游接近鄱阳湖口和沉积物中重金属的释放。 相似文献
936.
在不同温度和不同光照条件下对3株金龟子绿僵菌和1株贵州绿僵菌的液体深层培养研究表明,光照对菌丝生长和液生分生孢子产量均无显著影响。但培养温度显著影响菌丝生长和液生分生孢子的产出率,25-28℃为液体深层培养绿僵菌的适宜温度,其中以28℃最佳,对3-4龄马尾松毛虫幼虫的室内毒力测定表明,绿僵菌液生分生孢子的毒力略低于气生分生孢子。 相似文献
937.
应用发光菌测定有机化合物的毒性 总被引:11,自引:4,他引:11
本文介绍了化合物对发光菌半数抑制发光强度的毒性测定方法,测定了几十种芳烃类化合物的毒性,发现不同取代基或取代位置的芳烃毒性不同,并且对发光菌的毒性与对黑呆头鱼的毒性有相关性。 相似文献
938.
Adjustment of parental effort to manipulated foraging ability in a pelagic seabird,the thin-billed prion Pachyptila belcheri 总被引:6,自引:0,他引:6
Henri Weimerskirch Olivier Chastel Luc Ackermann 《Behavioral ecology and sociobiology》1995,36(1):11-16
An experiment was designed to examine in a long-lived seabird, the thin-billed prion (Pachyptila belcheri), how adults adjust their food provisioning strategy when their foraging abilities are reduced and when the chick's needs are increased. To reduce the foraging abilities of adults we impaired their flying ability by removing some flight feathers (handicapped), and to increase the food needs of the chick one parent was retained (single). Birds made either short foraging trips lasting 1–3 days, or long trips lasting 5–9 days. Control birds alternated long and short trips whereas single birds or handicapped birds made several successive short trips and thereafter a long trip. In each treatment, food loads tended to be heavier after long trips than after short trips, and single birds tended to bring heavier loads than control or handicapped birds. Birds in the three treatments lost similar amounts of mass after short trips and gained similar amounts of mass after long trips. However, the mass of handicapped birds declined through the experiment, while that of control and single birds remained stable. Although the proportion of chicks that died during the experiment was similar among the three treatments, the chicks fledged by a single bird were lighter than those in control nests. The results of the experiment suggest that thin-billed prions adjust their breeding effort differently to decreased flying ability or increased food demand by the chick. Single birds increase foraging effort without allowing their condition to deteriorate. Conversely, handicapped birds are unable to maintain their body condition while sustaining the chick at the same rate as control birds. It is suggested that in this long-lived seabird, adults probably adjust their breeding effort so that they do not incur the risk of an increased mortality, this risk being monitored by the body condition. 相似文献
939.
在中温(35±1)℃厌氧条件下,以葡萄糖为共基质,采用间歇试验方法,首先,研究了3-硝基酚(3-NP)的厌氧产甲烷毒性。试验以累计产甲烷量和相对活性(RA)为指标,评价了不同浓度3-NP对产甲烷菌的抑制程度,结果表明,3-NP浓度<40 mg/L时,对产甲烷菌几乎没有抑制作用,浓度为80 mg/L时产生轻度抑制,浓度为160 mg/L时产生中度抑制,浓度为320~800 mg/L时产生重度抑制。然后,分别用未驯化污泥和经3-NP驯化的污泥研究了3-硝基酚的降解动力学,结果表明,驯化后污泥比未驯化污泥对3-NP的降解能力提高了很多;驯化污泥的3-NP动力学可用方程R=SRm/Ks++SS2/Ki来描述,并利用非线性拟合求得动力学参数Ks、Rm、Ki分别为52.4 mg/L,1.70 mg/(g.h),87.9 mg/L,方差R2=0.99,拟合效果很好。 相似文献
940.
四氯化碳浓度对其自身厌氧生物降解的影响 总被引:1,自引:0,他引:1
研究饱和(含APL与DNAPL两相)与非饱和(只含APL一相)四氯化碳污染中,初始浓度对其自身生物降解的影响及其对微生物的影响。富集培养的高效降解菌是从污染源区土壤钻孔中筛选到的。研究表明,在实验浓度(v/v)范围内,随初始浓度升高,四氯化碳降解效率降低,对微生物的抑制作用增加。>0.1%~0.2%的四氯化碳(APL与DNAPL两相)对微生物生长有明显的抑制延滞作用。该降解菌群对<0.005(%APL)的四氯化碳污染降解效率很高;经驯化后,能降解初始浓度更高的四氯化碳污染。在降解产物中检测到氯仿,分离纯化的降解菌初步鉴定为链状杆菌、革兰氏阳性。 相似文献