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351.
杨锋  高松峰  袁春  袁涛 《资源开发与市场》2012,28(7):628-631,635
耕地和基本农田保护对矿业城市来说具有特殊的意义.以典型矿业城市——山西省朔州市为例,结合当地第三轮土地利用总体规划修编(2006-2020年),以当地2005年(规划基期年)耕地和基本农田的数量、质量为基础,分析其动态流向特征,最后根据自然气候、社会经济条件与耕地质量的一致性,将规划期内(至2020年)朔州市耕地划分为3个区域,分别探讨了各区域耕地利用、土壤改良和生态环境保护方向.  相似文献   
352.
通过对我国二氧化硫污染现状及控制要求的分析,提出了氨/硫铵法作为一种资源回收型脱硫方法,具有反应速度快、工艺流程简单、吸收剂利用率高、适用范围广及可实现资源回收利用的特点;以工程案例的形式分析了氨/硫铵法的技术经济指标,并对氨/硫铵法的应用前景和市场需求进行了预测。  相似文献   
353.
针对应用于实际工业化的树脂固定床吸附研究较少,而与之相关的固定床吸附穿透曲线可以用来确定固定床吸附操作参数,为固定床的设计和实际操作提供指导。通过对恒定波振荡理论和吸附等温方程的联合,来预测固定床吸附穿透曲线;并研究了不同操作条件对大孔弱碱树脂吸附对硝基酚穿透曲线预测模型的影响。以期望为树脂固定床的设计和实际工业应用产生指导意义。  相似文献   
354.
中美环保产业对比分析研究   总被引:1,自引:0,他引:1  
基于对中美两国环保产业的内涵、法律法规、经济政策及市场化发展情况等方面的比较和分析,探讨了中美两国环保产业发展中存在的异同点,针对我国环保产业发展中存在的不足提出了加快我国环保产业发展的政策建议。  相似文献   
355.
发展园区是新疆走新型工业化道路、实现跨越式发展的有效途径。但目前新疆园区布局中存在一些亟待解决的问题。分析了目前新疆园区布局现状、存在的问题及原因,并提出了促进园区可持续发展的建议。  相似文献   
356.
Quinestrol is synthetic estrogen used in contraceptive and hormone replacement therapy and occasionally for treating breast cancer and prostate cancer. It can make its way into the environment through sewage discharge and waste disposal produced by human excretions. In this study, the photodegradation kinetics of quinestrol in various conditions was investigated by UV and solar irradiation. The affecting factors were studied including concentration of hydrogen peroxide, different water types, and the initial concentrations of quinestrol. Concurrently, the transformation products and presumed pathways of quinestrol in distilled water by UV irradiation were identified and proposed. The results showed that the degradation of quinestrol in both irradiation conditions followed the pseudo-first-order kinetics. More rapid degradation was observed by UV irradiation (k = 0.018 min−1) than solar irradiation (k = 0.004 h−1), and the photodegradation rate of quinestrol depended on the concentration of hydrogen peroxide, the initial concentration of quinestrol and water types. The transformation products of quinestrol in distilled water were identified by gas chromatography/mass spectrometry. When exposed to UV irradiation, quinestrol in aqueous solution was rapidly degraded, giving at least ten photodegradation products. The chemical structures of ten degradation products were identified on the basis of mass spectrum interpretation and literature data.  相似文献   
357.
This paper investigated the degradation kinetics of norfloxacin in a soil, and its effects on soil respiration and nitrogen transformation under different conditions. Compared to the sterile control, the degradation rates of norfloxacin in the non-sterile soil were greatly enhanced, suggesting that microorganisms played a major role in the degradation. Accelerated degradation for norfloxacin in the soil was observed with decreasing concentrations (30 mg/kg to 5 mg/kg) with its half-life decreasing from 62 days to 31 days. Amending swine manure into the soil and increasing the soil moisture level enhanced the biological degradation of norfloxacin. No obvious inhibition of norfloxacin on soil respiration was observed in the soil, while only slight effect on nitrogen transformation was found. The results suggested that norfloxacin at the reported environmental concentrations (<100 mg/kg) would have little effect on microbial activity and functions in the soils.  相似文献   
358.
Bioaugmentation for the removal of polyaromatic hydrocarbons (PAHs) from wastewater using bacteria and yeasts is considered environment-friendly and a cost-effective technique. The effectiveness of this biodegradation system depends on the stability of inoculated microorganisms and the availability of nutrients. This study is aimed to investigate the removal of high molecular weight (HMW)-PAHs from biologically treated produced water using different biological systems. Three systems, inoculated with activated sludge (AS), the mixture of five yeast strains (MY), and the mixture of AS and the five yeast strains (SY), respectively, were constructed, and their performance for the removal of HMW-PAHs was compared over 10 weeks. The effluent of the biologically treated produced water from an oilfield was used as the influent after chrysene and benzo(a)pyrene were spiked as HMW-PAHs. Polymerase chain reaction-based denaturing gradient gel electrophoresis (PCR-DGGE) and fluorescent in situ hybridization (FISH) techniques were used to examine the changes in the structures and abundances of the bacterial and yeast communities in these three systems. Only SY and MY systems were capable to remove chrysene (90.7 % and 98.5 %, respectively) and benzo(a)pyrene (80.7 % and 95.2 %, respectively). PCR-DGGE analysis confirmed that all of the five yeast strains inoculated remained in the SY and MY systems, while FISH results showed that the relative abundance of yeast in the SY and MY systems (10.6 % to 21.9 %, respectively) were significantly higher than AS system (2.3 % to 7.8 %, respectively). The relative abundances of the catechol 2,3-dioxygenase (C23O) indicated that the copy number ratios of benzene ring cleavage gene C23O in the yeast amended systems were much higher than that in the AS system. In this study, all of the three systems were effective in removing the low molecular weight (LMW)-PAHs, while HMW-PAHs including chrysene and benzo(a)pyrene were efficiently removed by MY and SY systems, not by AS system. The high HMW-PAHs removal in the MY and SY bioaugmentation systems possibly attributed to the inoculation of the mixed yeast culture. By combining the PCR-DGGE results with the FISH analyses, it was found that yeast probably consisting mainly of the five inoculated strains inhabited in the two bioaugmentation systems as a dominant population. The relatively higher performance of the SY system might be attributed to the suspended growth type which permitted a more efficient contact between microbial cells and contaminants. The bioaugmentation systems (SY and MY) were successfully established by inoculating with five nonindigenous yeast strains and demonstrated high performance in removal of HMW-PAHs.  相似文献   
359.
SRT对MBR污泥性质的影响   总被引:1,自引:0,他引:1  
以浸没式膜-生物反应器(SMBR)处理模拟赖氨酸废水为研究体系,考察SRT在10、20和40 d条件下,SMBR中的胞外聚合物(EPS)组分和含量、污泥沉降性能和污泥相对疏水性等污泥性质的变化及其对膜污染的影响。结果表明,随着SRT的延长,混合液中EPS总量呈递减趋势,TBEPS中蛋白质与多糖的比值呈上升趋势,污泥的沉降性能变差,相对疏水性增强;膜通量下降速率变大,膜污染加重。污泥性质与膜污染的相关性表明,膜污染与蛋白质和多糖的比值、污泥沉降性能和相对疏水性呈正相关关系,而与EPS呈负相关关系。  相似文献   
360.
基于PROMETHEEⅡ法的污染场地土壤修复技术筛选及应用   总被引:5,自引:0,他引:5  
依据当前污染场地土壤修复技术特点以及场地特征,构建4层12指标21方案的污染土壤修复技术决策分析结构,运用多属性决策分析方法——PROMETHEEⅡ偏好排序法,对当前场地修复技术以及典型场地条件进行了客观分析和综合评价,实现基于具体修复目标的污染场地土壤修复技术择优筛选,并采用该方法对虚拟特定污染场地的土壤修复技术筛选进行了实例应用。这为污染场地的治理和修复提供了方法依据和理论参考。  相似文献   
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