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931.
流式细胞术在铜对藻类生态毒理研究中的应用 总被引:8,自引:0,他引:8
用流式细胞术研究了铜对铜绿微囊藻的毒性作用 ,结果表明 ,一定浓度的铜对藻类的生长具有抑制作用 ,而且这种抑制作用随着铜浓度的增加而增加 ,96h的EC50 为 82 86μg·l- 1 ,当铜浓度为 1 0 1 2 5 μg·l- 1 时 ,藻细胞的生长几乎完全受到抑制 .流式细胞仪检测结果可以说明铜对藻类群体作用的过程 ,即铜并不是同时对所有的藻细胞产生抑制作用 .低浓度时只是对部分细胞产生抑制 ,随着铜浓度的升高 ,受到抑制的细胞也越多 ,当达到最高浓度时 ,几乎所有细胞的生长都受到抑制 . 相似文献
932.
双硫腙-醋酸丁酯萃取石墨炉原子吸收法测定海水中痕量铜、铅和镉 总被引:2,自引:0,他引:2
用双硫腙-醋酸丁酯萃取石墨炉原子吸收法测定海水中痕量Cu,Pb,Cd。试验选定了测定条件,结果表明,在弱碱性介质中,能同时定量萃取Cu,Pb,Cd。方法的相对标准偏差〈3%。加标回收率92%-102%,检出限分别为Cu0.06,Pb0.14,Cd0.002。本法操作简便,快速,已应用于海水中Cu,Pb,Cd的分析,取得令人满意的结果。 相似文献
933.
934.
935.
高浓度Cu-COD废水处理方法研究 总被引:3,自引:0,他引:3
采用化学凝聚-生物流化床法对含Cu1700—3800mg/L和COD3900—5400mg/L的Cu-COD)废水进行处理试验研究。着重研究了生物流化床挂膜驯化条件和废水停留时间、容积负荷,气水比及化学凝聚条件等与去除COD和Cu的关系。试验结果表明,采用凝聚-生物流化床组合工艺并在控制适宜条件下,处理高浓度Cu-COD废水是有效的,处理后排放水中铜浓度可达0.20—0.82mg/L,COD可达150—180mg/L,铜总去除率可达99.97%,COD总去除率可达95%—96%。 相似文献
936.
The cadmium and copper levels were determined in the total of 126 fish samples which belongs to five fish species collected
from Sır and Menzelet Dam Lakes in Kahramanmaraş Province by Atomic Absorption Spectrophotometer. The concentrations of heavy
metals were expressed as ppm wet weight of tissue. The mean levels of cadmium and copper in muscle, liver and gill tissues
of Cyprinus carpiofrom the Menzelet Dam were found as 0.27, 0.91, 1.49 and 0.94, 1.2, 1.05, respectively. The mean levels of Cd in the muscle
tissues of Leuciscus cephalusfrom the Menzelet Dam were found 0.32 ppm, Cd wasn't found in tissues of liver and gill. The mean levels of Cu in the muscle,
liver and gill tissues were found as 3.17 ppm, 1.19 ppm, 0.96 ppm, respectively. The mean levels of the Cd and Cu in muscle
and gill tissues of Acanthobrama marmid from the Sır Dam were found as 1.28, 2.64 and 0.72, 0.08, respectively. The levels of the Cd and Cu in muscle tissues of
Cyprinus carpiofrom the Sır Dam were found 0.87 and 0.02 ppm, respectively. The mean levels of the Cd and Cu in the muscle and gill tissues
of Chondrostoma regium from the Sır Dam were found to be 0.80, 2.62 and 0.67, 1.34 ppm, respectively. The mean levels of the Cd in the muscle tissues
of the Silurus glanis was found as 0.60 ppm. In the muscle of the Silurus glanis from the Sır Dam, Cu was not found. The Sır Dam is more polluted than the Menzelet Dam from the point of Cd but less polluted
than the Menzelet Dam From the point of Cu. A relationship was determined between species and their habitating region in terms
of the levels reflected metal residues. In this study it was emphasized that the amounts of Cd and Cu in the samples were
low, however, seas, lakes, rivers, soil, air and consumed foods etc. has to be controlled routinely. 相似文献
937.
Coğun HY Yüzereroğlu TA Firat O Gök G Kargin F 《Environmental monitoring and assessment》2006,121(1-3):429-436
Samples of Mugil cephalus and Mullus barbatus were collected in the Northeast Mediterranean coast of Turkey the contents of cadmium, copper, iron, zinc and lead in the liver, gill and muscle tissues were determined by atomic absorption flame spectrophotometry.Except for lead, highest levels of each metal were found in the liver and this was followed by the gill and muscle in both species. Among the metals analyzed, Cu, Zn and Fe were the most abundant in the different tissues while Cd and Pb were the least abundant both in M. cephalus and M. barbatus. Seasonal changes in metal (Cd, Cu, Pb, Fe and Zn) concentration were observed in the tissues of both species, but these seasonal variations may not influence consumption advisories. In general, the highest concentrations were detected for all metals in summer. 相似文献
938.
Influences of excessive Cu on photosynthesis and growth in ectomycorrhizal Pinus sylvestris seedlings 总被引:5,自引:1,他引:4
Growth and photosynthesis responses were measured for Scots pine( Pinus sylvestris L. cv. ) inoculated with ectomycorrhizal fungi ( Suillus bovinus ) under 6.5 and 25 mg/L Cu treatments to evaluate ectomycorrhizal seedlings‘ tolerance to heavy metal stress. Results showed that excessive Cu can significantly impair the growth and photosynthesis of pine seedlings, but such impairment is much smaller to the ectomycorrhizal seedlings. Under 25mg/L Cu treatment, the dry weight of ectomycorrhizal seedlings is 25% lower than the control in contrary to 53% of the non-mycorrhizal seedlings, and the fresh weight of ectomycorrhizal roots was significantly higher than those of non-mycorrhizal roots, about 25% and 42% higher at 6.5 and 25 mg/L Cu treatments respectively. Furthermore,ectomycorrhizal fungi induced remarkable difference in the growth rate and pigment content of seedlings under excessive Cu stress. At 2.5 mg/L Cu, the contents of total chlorophyll, chlorophyll-a and chlorophyll-b were 30% higher in ectomycorrhizal plants than those in non-mycorrhizal plants. O2 evolution and electron transport of PSI and PSII were restrained by elevated Cu stress. However, no significant improvement was observed in reducing the physiological restraining in ectomycorrhizal seedlings over the non-mycorrhizal ones. 相似文献
939.
由于缺乏合适的放射性同位素,生物对Cu的吸收以及Cu在生物体内的迁移转化等动力学研究一直较为匮乏.论文以大型溞(Daphniamagna)为受试生物,以稳定同位素65Cu作为示踪剂,研究了不同Cu浓度下,大型溞对水相中Cu的吸收.结果表明,在低浓度下,大型溞的吸收随着水相中Cu浓度的增加而增加.随着水相中Cu浓度的升高,大型溞的吸收逐渐趋于饱和.水相吸收速率和Cu的暴露浓度符合米氏方程(Michaelis-Menten Function),最大吸收速率Imax为14.6μg·g-1·h-1,米氏常数Km为3.2μg·L-1,平均水相吸收速率常数ku为1.23L·g-1·h-1. 相似文献
940.
为了研究饲料中铜暴露对吉富罗非鱼幼鱼的毒性作用,将1 080条罗非鱼幼鱼暴露于6个浓度梯度的高铜日粮中,通过60 d的暴露试验,测定罗非鱼血红细胞微核变化和组织中铜的蓄积.结果表明,铜在各组织中积累量的顺序依次为:肝脏>脾脏>肠道>鳃>肌肉,与对照组相比,其中肝脏、脾脏、肠道中铜的含量随着时间和日粮中铜浓度的升高而逐渐升高,而鳃和肌肉中铜含量无显著差异;罗非鱼幼鱼血红细胞微核率、核异常率、总核异常率与日粮中铜的浓度存在一定的剂量—效应关系,并且核异常率高于微核率. 相似文献