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161.
ABSTRACT: The geochemistry and nature of the flow of ground water not only control the supply potential but constitute clues to the whole geology of an area. A study has been made of the largest available assemblage of data from 161 wells for the Island of Montreal collected by the Geological Survey of Canada in 1951–53. Data indicated that the system is generally subartesian, flowing from the principal topographically high areas towards the shores of the Island. As the probable use is about 13% of the estimated recharge of 140 million liters per day, most wells could be supplied by local recharge. The study has confirmed the predominance of calcium bicarbonate ground water from the carbonate sequence. The waters appeared to be saturated with respect to CaCO3 in all but 10 wells. The presence of other types of waters suggests the effects of the igneous intrusions of the area, the post-glacial marine submergence and the upward movement of waters from deep sources through fault and other structural zones. Confirmation of the significant variations in chemical composition in some neighboring wells indicated the future need for repetitive sampling from specific horizons for chemical and isotopic analyses. 相似文献
162.
锂的用途及其资源开发 总被引:14,自引:0,他引:14
林大泽 《中国安全科学学报》2004,14(9):72-76,94
锂在原子能工业中具有十分独特的地位 ,被誉为“高能金属” ;它推动着能源工业 ,尤其是电池技术的发展 ,无愧于“能源金属”和“推动世界前进的金属”的称谓。随着技术的发展 ,世界锂业的传统格局和市场分布发生了较大的变革 ,盐湖提锂技术的进步打破了半个世纪以来锂资源的分布和供应格局 ,而澳大利亚、俄罗斯、加拿大和津巴布韦等硬岩型锂资源大国将失去其在世界锂资源和锂盐供应市场上的优势。智利、中国、阿根廷和玻利维亚等国将成为世界拥有锂资源大国。盐湖工业生产的锂产品适应于当今知识经济时代的需求 ,市场前景广阔。笔者介绍了金属锂的一些重要用途 ;分析了锂资源开发的现状 ;指出我国盐湖卤水提锂技术已取得了重大突破 ;透露了作为国家计委批准的西部高技术产业化示范工程项目有关信息 ,年产 30 0 0吨碳酸锂生产线 ,将于2 0 0 5年 6月正式投产。 相似文献
163.
简要介绍了钙在机体内的吸收情况,并就碳酸钙在食品领域目前的应用及可能的开发途径进行了介绍,预测了今后碳酸钙在食品领域的发展方向。 相似文献
164.
165.
湖南黄沙坪铅锌矿尾矿富含碳酸盐及金属硫化物,属于碳酸盐型尾矿。通过对该尾矿铅垂剖面的结构构造,以及尾矿的矿物成分、化学成分、Paste pH值和Carb-ANC(酸中和能力)等分析,探讨碳酸盐型尾矿的酸化特征及其机制。研究表明:黄沙坪尾矿发育层状构造,即表面为胶结硬化层(hardpan),之下依次为弱胶结层、尾砂层及底层(接近尾矿潜水面)。尾矿的酸中和矿物主要为方解石;尾矿的产酸矿物以黄铁矿和磁黄铁矿为主,但黄铁矿的抗氧化能力和产酸能力均较强于磁黄铁矿。尾矿剖面自下而上(或由早至晚),氧化作用逐渐增强,磁黄铁矿先于黄铁矿氧化(蚀变)分解并逐渐消失,此时尾矿的酸中和能力仍较强,尾矿保持近中性环境;之后,黄铁矿开始氧化产酸并大量消耗方解石,尾矿开始酸化;至尾矿表层方解石消耗殆尽,而黄铁矿仍持续释酸,尾矿酸化加剧。表层强氧化环境使纤铁矿大量沉淀并胶结尾矿颗粒形成硬层。黄沙坪尾矿由于含有大量的抗氧化能力和产酸能力均较强的黄铁矿,其酸水(+重金属)释放的潜力较大并且持续的时间也较长。 相似文献
166.
Electrolytic manganese residue (EMR) is a type of solid waste discharged from the process that converts solid manganese carbonate of rhodochrosite into soluble Mn(II) and generates anode mud under electrolysis. The experimental material was a filtrate created by using distilled water as a dispersal agent for the EMR, followed by simple filtration. A calculated amount of sodium carbonate was added to recover the soluble Mn(II) via precipitation into manganese carbonate. Data showed that Mn concentration may be markedly decreased from 2069 to 36 mg/L, thereby reaching a recovery rate as high as 98%. Analysis demonstrated that precipitation of Mn(II) from a leached aqueous solution followed first-order kinetics. The findings indicate that the reaction rate constant decreased as temperature gradually rose and that its apparent activation energy Ea was ?10.48 kJ/mol. 相似文献
167.
对苯二酚生产中含硫酸锰废水的综合利用 总被引:1,自引:0,他引:1
根据硫酸锰废水的特性,采用中和除铁和硫化除钴、镍等方法先使废水净化,得到合格电解液.其后对该电解液通电并加入硒电解24小时,再经钝化等处理制得金属锰.利用电解硫酸锰后的阳极废水制取碳酸锰,并从碳酸锰废水中回收硫酸铵.本工艺简单可行,产品金属锰纯度达99.8%以上,经济和环境效益显著. 相似文献
168.
基于磷酸盐和碳酸盐对铅的高亲和特性,将蛋壳与厨余垃圾煅烧制备的含钙生物炭除磷后(ES-BC/P),用于水体中铅的去除.结果表明,ES-BC/P在较优的投加量下对不同浓度的铅(1~100 mg·L-1)均具有较好的去除性能,去除效率均高于99%,且反应后磷的释放量较低;ES-BC/P偏碱性,因含铅污染液呈弱酸性,ES-BC/P加入后无需调节体系的pH值即可达到较好的去除效果;反应动力学及等温线实验表明,ES-BC/P除铅主要为单层化学吸附,最大吸附容量为493.12 mg·g-1(318 K);表征分析结果表明,铅主要通过与ES-BC/P中的Ca-P化合物和CaCO3进行反应,Pb2+可与Ca2+发生交换作用,形成 Pb5(PO4)3OH、Pb10(PO4)6(OH)2、PbCO3和Pb3(CO3)2(OH)2等沉淀而被去除.综上所述,除磷后的ES-BC材料可实现水体中铅的高效去除,从而实现废弃物的资源化利用. 相似文献
169.
Abboud IA 《Environmental geochemistry and health》2008,30(5):445-463
Urinary stone diseases are increasing in the Middle East. The majority of urinary stone cases are found in the northern part of the country. Stone samples taken from patients living in the Irbid area were collected from Princess Basma Hospital. The present study concentrates on the mineralogical and chemical composition of the urinary stones and on the effective environmental factors that assist in developing the different types of urinary stones. Using X-ray diffraction techniques, the mineralogical composition of the urinary stones was found to be as follows: oxalate, cholesten, and uric acid, with cystine stones occuring more frequently than the others. Cholesten and calcium oxalate stones are the most dominant types of stones. Calcium oxalate is the most common type of oxalate stone. Calcium oxalate is represented in: whewellite, wheddellite, and calcium carbonate oxalate hydrate minerals, in addition to other minerals such as brushite, ammonium phosphate, vaterite, valleriite, and bobierrite from other types of stones. Bobierrite (phosphate group) is a new mineral reported in urinary stones, and this has not been determined in any previous study worldwide. Apatite (calcium phosphate) is deduced using scanning electron microscope (SEM) images. The SEM technique determined crystal forms and systems, shapes, morphological features, and the names of the minerals forming urine stones, while optical properties are studied by polarizing microscope. X-ray fluorescence technique determined the concentrations of major and some trace elements. It revealed that Ca is the main constituent of the urinary stones, especially those composed of calcium oxalate and calcium phosphate. The concentration of trace elements was Ba = 1.57, P = 3.61, Fe = 1.78, S = 2.08, Zr = 4.63, Mo = 3.92, Cu = 1.89, Co = 1.56, and F = 4.2% and was higher in the urinary stones of Jordanian patients than in foreigners in the country. Questionnaires completed by patients suggest that the most significant factors directly effecting the formation of stones are water, climate conditions, food rich in protein and rich in different chemicals. Moreover, some drugs and diseases might also help in developing other stones. 相似文献
170.
采用FeSO_4和Na_2S作为还原剂处理铬污染紫色土壤,研究了还原过程中铬的含量及形态的变化。实验结果表明:当FeSO_4加入量为1.5%(w,下同)时,浸出Cr(Ⅵ)含量由(1 745.13±27.93)mg/kg降至(17.65±2.28)mg/kg,浸出总铬含量由(1 768.83±57.24)mg/kg降至(69.79±8.61)mg/kg,铬形态由水溶+碳酸盐结合态转变到较稳定的铁锰结合态;当Na_2S加入量为0.4%时,浸出Cr(Ⅵ)含量由(1 745.13±27.93)mg/kg降至(25.50±0.12)mg/kg,浸出总铬含量由(1 768.83±57.24)mg/kg降至(410.87±12.83)mg/kg,铬形态由水溶+碳酸盐结合态转变到铁锰结合态和有机结合态。 相似文献