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排序方式: 共有357条查询结果,搜索用时 15 毫秒
1.
EM技术在我国水环境保护中的应用研究进展   总被引:4,自引:0,他引:4  
对EM技术在我国水环境保护中的应用情况进行了综述,重点介绍了EM技术应用于废水处理领域的研究进展,同时还展望了将来的应用及研究前景.  相似文献   
2.
从厌氧反应器的发展谈UASB反应器的改良   总被引:10,自引:0,他引:10  
对厌氧反应器的发展沿革、技术现状和研究进展进行了较为全面的总结。介绍了第 1代、第 2代和第 3代厌氧反应器的特点及应用状况。分析了厌氧反应器的发展趋势 ,对比了 EGSB、IC反应器与 UASB反应器的结构特征 ,提出并验证了改良 UASB反应器。结果显示 ,改良 UASB反应器有利于提高负荷和设备开发。  相似文献   
3.
该文报道碱厂废水随浓度变化的光谱实验。分析碱厂废水的光谱特征 ,并与相同浓度的海水悬浮泥沙水体的光谱进行比较 ;确定该废水特征波长为 50 1.3nm。根据光谱实验结果 ,结合当前已有的水色传感器的资料 ,选择两个卫星传感器波段 :Sea WIFS第四频道 (497.2~ 52 1.6 nm)和TM第二频道 (518.9~ 6 0 0 .2 nm) ;利用数字对 (R,c) ,建立了反射率与该污染水体浓度间的相关模式。为遥感技术大面积、快速地监测碱厂废水污染水体提供理论依据。  相似文献   
4.
耗氧速率(OUR)测量方法的实验研究   总被引:4,自引:0,他引:4  
目前多采用分批实验法和呼吸测量仪测量耗氧速率,而耗氧速率的测量对于研究活性污泥数学模型中的动力学参数及废水特性鉴定具有重要意义。本文根据OUR测量方法的基本原理设计了1种简易的OUR测量装置,为检验测量装置的有效性,设计了相关实验进行验证。在内源呼吸实验中,测定了所用活性污泥的内源呼吸速率是5.1mgO2/L·h,污泥的衰减系数是0.0137h-1,比文献值略高。基质降解实验对人工配水(葡萄糖和淀粉)的耗氧速率进行了测定,实验结果显示有3个显著不同的耗氧速率,分别为35mg/L·h,13mg/L·h,6mg/L·h,它们各代表葡萄糖降解、淀粉降解和内源呼吸的速率。内源呼吸速率高于前1个实验是由于基质降解过程中污泥量增加所致。并计算出异养菌产率系数Kd为0.63mgVSS/mgCOD,Kd略低于文献值。实验结果证明,该装置能很好的实现测量目的。  相似文献   
5.
This paper reports a study of the field measurements and monitoring of wastewater discharge in sea water at Bari East (Italy). A wastewater sea outfall system is an integral and fundamental part of each wastewater treatment with ultimate sink in the sea water. The design of a water treatment plant and wastewater outfall must take into account the use of the environmental water, the values of physicochemical parameters to be respected in order to safeguard the use itself and the quality of the environmental water where wastewater is issued. In the present study measurements of sea current velocity components were carried out with a VM-ADP (Vessel-Mounted Acoustic Doppler Profiler). Salinity, wind directions and velocities were assessed with, for one survey, the total faecal coliforms and other biochemical parameters. It was emphasized that the measurements necessary for monitoring cannot be concentrated in the wastewater outfall pipe zone only, but should be extended to a neighbouring area of the outfall pipe, with an extension depending on the wastewater discharge, the polluting charge and the magnitude of the sea currents and the winds typical of the zone of interest. The analyses presented in this paper confirm that the sea zones close to the wastewater outfall pipe are particularly sensitive and vulnerable. Such results must be considered in the planning of a wastewater outfall pipe.  相似文献   
6.
海洋褐藻胶生产废水的絮凝-氧化处理研究   总被引:2,自引:0,他引:2  
使用新型高效的絮凝剂Xp,对海洋褐藻胶生产废水进行絮凝,催化氧化处理试验,确定了絮凝剂Xp的最佳使用条件,催化氧化时间和氧化剂用量,结果表明,经本工艺处理后,废水中主要污染物CODcr的去除率达到83.9%,处理后的废水基本达到国家《污水综合排放标准》(GB8978-1996)限定的二级标准。  相似文献   
7.
Selenium (Se) is an essential micronutrient to biota, but can become a potent toxicant at elevated concentrations. The natural sources and chemical properties of Se species make the boundary between deficiency and toxicity narrow for some biota, with both phenomena common around the globe. Large areas of farmland in the Colorado River Basin (CRB) generate salinized drainage water with Se concentrations much higher than 5 μg/L, the U.S. Environmental Protection Agency chronic water-quality criterion for the protection of aquatic life. We have carried out detailed field and laboratory studies to investigate Se geochemistry and remediation in two of these areas: the Middle Green River Basin, Utah and the Salton Sea Basin, California, located respectively in the Upper and Lower CRB. Results from these and other studies show that approximately 90% of the dissolved Se in the Colorado River and its tributaries originally is derived from the Upper Cretaceous Mancos Shale and equivalent pyritic marine units that outcrop in the Upper CRB. Selenium is mobilized commonly by biogeochemical oxidation of this pyritic shale and is concentrated mainly as selenate (SeO4^2-) in soils and agricultural drainage water of dry climates by evaporation. Minor (0%-5%) amounts of Se are present as the selenite species (HSeO3^-) and (SEO3^2-), but these species and the more reduced species, elemental Se (SeO) and selenide (Se^2-), have much lower solubility and/or have high sorptive affinity towards organic matter, clay minerals and iron oxyhydroxides. The concentration of dissolved Se (-2.5 μg/L) and salinity in the Lower Colorado River water are among the highest of the world major rivers. Because of low precipitation (7 cm/a) and extreme evapotranspiration (-1.8 m/a) rates in the Salton Sea Basin, California, Se values in irrigation water imported from the Colorado River increase to 〉300 μg/L in drainage wastewater. Removal of Se from contaminated wastewater by nanofiltration membranes was demonstrated in laboratory and pilot-scale field experiments.  相似文献   
8.
In recent years, reclaimed wastewater as a water source for urban artificial landscape rivers is being rapidly developed in some coastal cities with limited water resource available in China. However, eutrophication occurs more often in the landscape waterbody with reclaimed wastewater than in natural rivers and lakes. The study of restoration and reconstruction of macrophytes, especially the submerged aquatic vegetation, is essential to inhibit eutrophication of reclaimed wastewater. This study investigated the seasonal variation of biomass of Ruppia maritima in the artificial landscape river using reclaimed wastewater as the only water source in Tianjin, China. It was found that there were two seasonal growth peaks of Ruppia maritima each year in the coastal reclaimedwastewater. The contents of nitrogen and phosphorus of Ruppia maritima varied with the season.  相似文献   
9.
A promising technique for the removal of heavy metal ions from wastewater streams involved firstly the ions adsorption on a colloidal precipitate (carrier) and then the separation of the loaded flocs (coagula) by a modified column flotation. Here, the effluent feed and the carrier (ferric hydroxide) enter smoothly by the top of the column through a special diffuser, in counter current with rising bubbles (100–600 μm diameter) generated by using recycled water, surfactant and air suction through a venturi. High separation values of the column flotation of the carrier precipitates were achieved, despite the high superficial flow rate and the high Fe+ 3 concentration utilized (> 60 mg L− 1 Fe). No rupture of colloidal carrier aggregates was observed and a low split was ensured by monitoring the concentrate (floated product) flow rate. Results indicated that best separation was attained by controlling the medium pH (for best heavy metal ion adsorption onto the carrier), followed by sodium oleate, used as “collector” and optimizing operating parameters (conditioning, flow rates, etc.). The column throughput reached 43 m h− 1 (m3 m− 2 h− 1), which is about 4 times the normal capacity of DAF-dissolved air flotation unit, the most used floater in wastewater treatment. Various metals (Cu, Ni, Pb, etc.) and molybdate ions present in synthetic and real effluent were successfully removed based on this colloidal adsorbing flotation principle. The process was also applied in a pilot scale to treat an industrial electroplating wastewater. Most of toxic metals (Cu, Ni and Zn) were reduced from initial concentrations of about of 2 to 10 mg L− 1, to below 0.5 to 1.0 mg L− 1, meeting local municipal discharge limits (but Cd ions). It is believed that flotation separation using medium-sized bubbles has great potential as a clean water and wastewater treatment technology.  相似文献   
10.
Water resources for agricultural development and landscape enhancement in Kuwait are very scarce; the quality is saline (brackish), and the soil texture is sandy, incapable of holding nutrients and moisture. Most of the rainfall in Kuwait either evaporates due to the high temperatures or percolates through the soil. The rainfall is not sufficient to recharge the underground water supply. A variety of alternative water sources have been studied, including seawater desalination and wastewater treatment. Wastewater treatment proved to be convenient due to the relatively low salinity detected in the treated water. Furthermore, the amount of wastewater is expected to increase as more residential areas are connected to the sewage system as the population increases.

The development of a greenery plan for Kuwait requires intensive water management. This goal can be achieved through manpower training in landscape development, selection of plants tolerant to arid environments, usage of appropriate irrigation and drainage systems, promotion of greenery programs within public and the governmental agencies for their direct participation in urban area beautification, and extension of wastewater treatment techniques.  相似文献   

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