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461.
Electro-assisted regeneration of ion exchange resins 总被引:1,自引:1,他引:0
Zhigang LIU Ying WANG Yansheng LI Hui CHANG 《Frontiers of Environmental Science & Engineering in China》2008,2(4):410-414
Electro-assisted regeneration (EAR) for the mixed bed of strongly acidic cation and weakly basic anion exchange resins with
the Al(OH)3 suspension in a three-compartment cell was investigated. The desalination experiments were carried out to evaluate
the characteristic of the regenerated mixed resins. Experimental results showed that the efficiency of resin regeneration
was strictly dependent on the voltage, regeneration time, and feed regenerant flow rate. The amount of the effluent reached
50 times the volume of the resins bed, and the conductivity was less than 1.0 μs/cm. Compared to the conventional ER, the
total effluent volume of EAR was about 1000 mL more than that of ER under the same conditions, and the outlet conductivity
was significantly lower. The desalination and regeneration reaction mechanisms of the mixed resins indicated the regeneration
efficiency of resin with Al(OH)3 as the regenerant was much higher than that with H2O. 相似文献
462.
不同强度冷应激对大鼠肌肉、脾脏和肝脏中HSP70表达的影响 总被引:8,自引:1,他引:8
通过两个低温温度段对健康Wistar大鼠进行冷应激试验,利用免疫印迹技术检验肌肉、脾脏和肝脏中HSP70表达的相对变化情况,探讨不同时间和强度冷应激条件下,3种组织中HSP70表达的情况以及通过HSP70表达量的变化看是否可以将其作为评估冷应激的指标.正常饲养的大鼠环境温度为(20±1)℃,而实验组大鼠分别在(0±1)℃和(10±1)℃环境下进行低温冷应激,然后在冷应激后不同时间宰杀取组织,利用Western-blotting检测HSP70的表达量.结果表明:(1)在(0±1)℃急性冷应激条件下,随着冷应激时间的延长,肌肉和脾脏中HSP70的表达持续增加,与对照组(CK)相比,差异显著(P<0.05);(2)在(10±1)℃慢性冷应激条件下,仅1wk肌肉组中HSP70的表达增加(P<0.05),其它情况下各组织中HSP70的表达与CK相比无显著差异(P>0.05).上述结果说明,相应强度的冷应激可以诱导机体的HSP70表达,并且随时间延长,HSP70的表达增加,可以考虑将HSP70作为监测大鼠应激的指标.图1表2参14 相似文献
463.
通过实验室蝌蚪微空间温度行为变化频次统计分析,发现10℃时的所有西藏齿突蟾(Scutiger boulengeri)蝌蚪、15℃时除低海拔种群外的所有西藏齿突蟾蝌蚪的聚集分布均符合负二项分布,也符合NeymanⅡ型分布,在5℃、0℃时,不同分组的西藏齿突蟾蝌蚪行为分布有差异.西藏齿突蟾蝌蚪在低温5℃、0℃时的行为分布方式改变可能是对低温冻害的一种适应性反应,由环境温度改变导致蝌蚪行为分布方式的改变可能是高海拔两栖类蝌蚪对分布区域水温改变规律长期形成的一种适应对策.图1表2参12 相似文献
464.
龙眼胚性细胞悬浮培养再生植株 总被引:12,自引:1,他引:12
以龙眼胚性愈伤组织为起始材料 ,研究了胚性悬浮细胞培养的影响因素、继代保持方法及其体胚发生与植株再生 .结果表明 ,建立龙眼优良胚性悬浮细胞系的技术关键在于 :由松散型胚性愈伤组织作为起始材料 ;以去除琼脂的保持松散型胚性愈伤组织的培养基作为启动培养基 ;采用分别附加 5mgL-1AgNO3 、10 0mgL-1肌醇的培养基交替继代保持 .胚性悬浮细胞在附加 2 %蔗糖、0 .7%琼脂、4 0 0mgL-1LH、10 0mgL-1肌醇的MS固体培养基上形成的体胚数量可达 7× 10 4~ 14× 10 4g-1.经过成熟培养后 ,体胚转换植株的频率在 6 5 %以上 .图版 1图 1表 3参 16 相似文献
465.
从泰乐菌素产生菌弗氏链霉菌028-3菌株出发,通过NTG多次诱变,获得一株泰乐菌素产量提高2倍以上的突变株H188.再以原生质体再生和原生质作诱变后再生的手段,经过连续两轮处理,获得两株突变株:A117和D85.在最佳发酵培养基条件下,它们的泰乐菌素产量比H188分别提高6.5倍和5.5倍以上. 相似文献
466.
低温等离子体技术处理挥发性有机物 总被引:10,自引:0,他引:10
介绍了低温等离子体技术在处理挥发性有机物(VOCs)的研究现状和成果;探讨了低温等离子体技术的发展趋势. 相似文献
467.
根据理论分析提出生物吸附-沉淀-再生的城市污水处理工艺,即高负荷生物吸附再生法。该工艺对污染物去除的作用主要包括污泥的絮凝作用、吸附作用和生物代谢作用,而以前两者的作用为主。对城市污水的生产性试验研究结果表明,该工艺能够较大程度地提高SS、COD、SCOD和BOD等污染物的去除率,具有明显的处理效果,对于西北干旱缺水地区实现污水资源化是切实可行的方法。 相似文献
468.
Clements A 《Environmental monitoring and assessment》2004,99(1-3):233-243
Desertification of shrub and grassland into pinyon-juniper woodland is occurring over much of the Colorado Plateau in the
southwestern United States. As trees invade, they out-compete shrubs and grasses, increasing erosion rates and reducing infiltration
of moisture into the soil. This has caused habitat problems for wildlife, and reduced forage for livestock. These impacts
also affect the human communities that rely on ranching and tourism related to hunting. Past land use and management practices
including heavy livestock grazing, fire suppression and introduction of exotic annual plants are believed to have led to current
conditions. The Montrose office of the Bureau of Land Management has implemented an ecosystem-based program to reverse the
desertification process on public land. The program is centered on detailed landscape objectives describing the desired vegetation
mosaic on 360 000 ha of public land. The objectives outline proportions of plant seral stages and arrays of patch sizes for
each planning unit. These objectives are based on priority management issues and the need to replicate a natural vegetation
mosaic. Where the existing mosaic does not meet objectives, mechanical vegetation treatments and prescribed fire are used
to create early and mid-seral patches on the ground. This restored vegetation pattern and type should be sustained over time
through a natural fire regime and improved livestock management. Because many uncertainties exist, an adaptive management
process is being used that allows mosaic objectives to be changed or processes modified where monitoring or scientific research
indicate a need. 相似文献
469.
Young AL 《Environmental science and pollution research international》2003,10(2):82-88
The use of irradiation to improve the safety, protect the nutritional benefits, and preserve the quality of fresh and processed foods is a well established and proven technology. Over the past 35 years, the United States Government has invested in the science to confirm safety and in the technology to show application. The United States Department of Agriculture (USDA) and the Food and Drug Administration have approved sources of ionizing radiation for the treatment of foods, and their application to most meats, fruits, vegetables, and spices. Despite the value of this technology to the food industry and to the health and welfare of the public, only minimal application of this technology occurs. This underscores the importance of increasing the public's understanding of radiation risks relative to other hazards. Accordingly, in 1995, the Committee on Interagency Radiation Research and Policy Coordination of the Executive Office of the President made recommendations for the creation of a centralized National Radiation Information Center that would work closely with Federal departments and agencies in responding to public queries about radiation issues and Federal programs. This article updates a commentary published in 1996 (Young 1996). In the past six years, some progress has been made, including the establishment of a government operated Food Irradiation Information Center, and the completion of final rule making by USDA, thus permitting the safe treatment of meats and poultry. Despite these actions, little progress has been made on the public acceptance of this technology. The need for an informed public and for a better understanding of risks, i.e., risk communication, is noted. 相似文献
470.
吸附邻氯酚的超高交联树脂微波辅助再生研究 总被引:1,自引:0,他引:1
以NDA-150超高交联树脂为吸附剂,邻氯酚为吸附质,氢氧化钠稀溶液为脱附剂,采用微波间歇辐照的方法,对吸附氯酚树脂的再生过程进行了研究。系统分析了微波功率、辐照时间、碱液浓度对脱附效果的影响,并确定了最佳脱附条件。结果表明,微波辐照再生速度非常快。与传统热脱附不同,微波再生过程中脱附效率并不随碱浓度的增加而升高,微波辐照功率和辐照时间对脱附效果影响明显。树脂经多批次微波辐照,吸附性能和化学结构保持稳定。 相似文献