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121.
典型大气环境玻璃钢天线罩聚氨酯涂层工艺老化行为研究 总被引:1,自引:0,他引:1
通过南海海洋大气环境、海南万宁湿热乡村大气环境、西藏拉萨高原大气环境户外大气暴露对玻璃钢基灭线罩聚氨酯涂层工艺进行了老化试验,运用光泽、颜色、粉化率、SEM等手段测试了涂层在户外大气暴露的性能变化和表面形貌,并进行对比分析。结果表明,在相同大气环境中,工艺玻璃钢板/雷达罩底漆/浅灰航天聚氨酯涂层耐候性能优于工艺玻璃钢板/环氧聚酰胺/弹性聚氨酯磁漆涂层的耐侯性能;对于同种工艺,西沙海洋大气环境对其耐侯性的影响最大,其次是万宁湿热乡村环境,拉萨高原环境影响较小;光照、温度、湿度是涂层老化的主要原因。 相似文献
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为了探讨生物膜对汞的蓄积因素,研究了不同深度、不同培养时间、不同季节等条件对黄浦江生物膜中汞元素含量的影响,并对其存在形态进行分析.结果表明,生物膜中有机质含量较高(7.5%~14.5%);生长时间,水深,季节都是影响生物膜中汞元素蓄积的重要因素;光照越强,温度越高,生长时间越长,生物膜中汞元素含量越高;生物膜中残渣态(41.98%)和有机质结合态(27.89%)的汞含量比较高,碳酸盐结合态(10.17%)和铁锰氧化物结合态(5.33%)的汞含量相对较少. 相似文献
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Nilkanth N. Shinde 《International Journal of Sustainable Engineering》2016,9(3):189-196
The paper explores the experimental results of the prototype compound parabolic trough made of mild steel and silver-coated selective surface. This prototype has been tested with top cover. The performance of the collector has been evaluated with two kinds of receivers coated with three types of black coatings. First receiver is of copper coated with black copper, second receiver is of mild steel coated with black copper and third receiver is of copper coated with black zinc. From actual field experiments, it has been observed that the efficiency of the system achieved with copper receiver coated with black copper is comparatively higher than the other two types of receivers. A simple regression analysis is used to correlate the thermal performance parameters of the system. 相似文献
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A new potassium permanganate reagent with slow-release properties was designed and tested for possible application in in situ chemical oxidation. For this purpose, MnO2-coated KMnO4 particles (MCP) were prepared by partial reduction of solid KMnO4 using the acid-catalyzed reaction with n-propanol or the comproportionation of Mn(VII) and Mn(II) in n-propanol as reaction medium. Column tests showed that, for MCP with a residual KMnO4 fraction of 70 wt%, the duration of permanganate release under flow-through conditions was prolonged by a factor of 10 compared to untreated KMnO4. While KMnO4 is too soluble to be used in reactive barriers, MCP could be introduced into the aquifer by filling of trenches or boreholes; this would allow a prolonged passive dosing of permanganate into the flowing groundwater. In addition, experiments were conducted in order to determine the oxidation capability of native KMnO4 particles and MCP in CH2Cl2, a representative non-polar non-aqueous phase liquid (NAPL). It may be possible to utilize the significantly higher reactivity of MCP under these conditions for the design of slow-release permanganate particles for NAPL source treatment. 相似文献
128.
Selman Aydın Şehmus Altun Hüseyin Aydın 《International Journal of Green Energy》2016,13(11):1102-1108
In this study, the top surfaces of piston and valves of a four-strokes and direct-injection diesel engine have been coated—with no change in the compression ratio—with a 100 μm of NiCrAl lining layer via plasma spray method and this layer has later been coated with main coating material with a mixture of 88% of ZrO2, 4% of MgO and 8% of Al2O3 (400 μm). Then, after the engine-coating process, ultra-low sulfur diesel (ULSD) as base fuels and its blend with used frying cottonseed oil derived biodiesel in proportion of 20%, volumetrically, have been tested in the coated engine and data of combustion and performance characteristics on full load and at different speeds have been noted. The results, which were compared with those obtained by uncoated-engine operation, showed that thermal efficiency increased, and engine noise reduced. Cylinder gas pressure values obtained from the diesel engine which has been coated with thermal barriers have been found to be somewhat higher than those of the uncoated-engine. Also, maximum pressure values measured in both engines and under the same experimental conditions through the use of test fuel have been obtained after TDC. Moreover, heat release rate and heat release have occurred earlier in the coated-engine. NOx emissions were increased while CO and HC emissions were remained almost the same with a little bit decrease. 相似文献
129.
采用石英毛细管作为模具,甲基丙烯酸和乙二醇二甲基丙烯酸酯在石英纤维表面原位聚合得到聚(甲基丙烯酸-乙二醇二甲基丙烯酸酯)作为固相微萃取涂层,并以五氯酚为研究对象,采用顶空SPME-GC-ECD法对该涂层的萃取性能进行评价。使用正交试验优化萃取温度、萃取时间、盐浓度、pH和搅拌速度。在最优条件下,建立了水样中五氯酚的分析方法,方法检出限为1ng/L,线性范围为2~5000ng/L,线性相关系数为0.9999,相对标准偏差(RSD,n=5)为8.9%,加标回收率为110.8%。 相似文献
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本文提出了一种新的混合改进剂(锆+酒石酸),能有效消除高氯酸、硝酸以及各种基体的干扰,比较了各原子化温度时理论和实验特征量,使解热石墨管可可能用于石墨炉原子吸收法测定各种环境样品中的锡,准确度和精度优于8%。 相似文献