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991.
The feasibility for developing a protocol to assess marine water quality based on early colonization features of periphytic ciliate fauna was studied in coastal waters of the Yellow Sea, northern China. The ciliate communities with 3–28-day ages were collected monthly at four stations with a spatial gradient of environmental stress from August 2011 to July 2012. The spatial patterns of both early (3–7 days) and mature (>10 days) communities of the ciliates represented significant differences among the four stations, and were significantly correlated with environmental variables, especially nutrients and chemical oxygen demand (COD). Seven and eight dominant species were significantly correlated with nutrients or COD within the early and mature communities, respectively. The species richness indices were strongly correlated with nutrients, especially in mature communities. These findings suggest that it is possible to assess the status of water quality using early colonization features of periphytic ciliate fauna in coastal waters.  相似文献   
992.
Remanufacturing represents a business opportunity and in many cases a means to promote environmental sustainability. To help enterprises economically and effectively implement remanufacturing, a multi-criteria decision making (MCDM) model for selecting remanufacturing technology is developed. The model considers remanufacturing technology portfolios. The enterprise benefits associated with each portfolio, including economic and environmental benefits, are evaluated using six main criteria: cost, quality, time, service, resource consumption, and environmental impact. In addition, the synergies among the different types of technologies for each remanufacturing technology portfolio are also considered. The pair-wise comparison approach of Analytic Hierarchy Process (AHP) is employed for remanufacturing technology portfolio selection. An illustrative example is provided to lend insights into the application of this methodology.  相似文献   
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995.
介绍了油气回收技术的基本原理,着重介绍了冷凝膜回收工艺技术的特点,及冷凝膜回收装置在中国石化青岛石油化工有限责任公司轻质油汽车装车的应用情况,分析了存在的问题及改进建议。  相似文献   
996.
Environmental Geochemistry and Health - This study investigated the environmental geochemical characteristics of rare-earth elements (REEs) in surface waters in the Huainan mining area, Anhui...  相似文献   
997.

In this paper, a crosslinked carboxymethyl starch (CCMS) was prepared with corn starch as the raw material, epichlorohydrin as the crosslinking agent, and chloroacetic acid as the etherifying agent through a series of crosslinking, alkalization, and etherification reactions, respectively. Nano-TiO2 was loaded onto the surface of the CCMS by the sol-gel method to obtain a TiO2/CCMS composite. The TiO2/CCMS composite was characterized by XPS, XRD, SEM, and BET. XPS showed that the surface chemical composition of the TiO2/CCMS composite material contained titanium; XRD diffraction patterns indicated that the crystal form of the TiO2/CCMS composite was a combination of the CCMS and anatase TiO2. The surface morphology obtained by SEM showed that there were nano-TiO2 particles on the surface of the CCMS. The specific surface area of the TiO2/CCMS composite was larger than that of CCMS. The adsorption-photodegradation performance of the TiO2/CCMS composite was also studied under UV irradiation, and the results showed that significant adsorption-photodegradation synergies occurred.

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998.

In this study, Chlorella vulgaris, Ganoderma lucidum, and endophytic bacteria were co-cultivated with the stimulation of strigolactone analogs GR24 to prepare pellets. During the purification of biogas slurry and biogas, multi-walled carbon nanotubes (MWCNTs) were introduced to enhance the removal efficiencies of nutrients and CO2. The results showed that both GR24 and MWCNTs affected the purification of biogas slurry and biogas. The maximum chemical oxygen demand, total nitrogen, total phosphorus, and CO2 removal efficiencies of the Chlorella vulgaris-Ganoderma lucidum-endophytic bacterial symbionts were 82.57 ± 7.96% (P < 0.05), 82.14 ± 7.87% (P < 0.05), 84.27 ± 7.96% (P < 0.05), and 63.93 ± 6.22% (P < 0.05), respectively, with the induction of 10−9 M GR24 and 1 mg L−1 MWCNTs. Moreover, the growth and photosynthetic performance of the symbionts were consistent with the removal effects. The Chlorella vulgaris-Ganoderma lucidum-endophytic bacterial symbionts obtained high growth rates and enzyme activity with the maximum growth rate of 0.365 ± 0.03 d−1, mean daily productivity of 0.182 ± 0.016 g L−1 d−1, and carbonic anhydrase activity of 31.07 ± 2.75 units, respectively. These results indicated that an appropriate concentration of GR24 and MWCNTs could promote the growth of symbionts, reinforce the purification effects of biogas slurry and biogas, and provide a new idea for the simultaneous purification of wastewater and biogas.

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999.
赵振华  姜大立  张立 《灾害学》2014,(1):177-181
将寄售式储备引入应急物资储备体系,针对这一模式下的物资轮换更新问题,根据物资的特点构造了物资相对性能函数,分析了供应商实施轮换更新的条件,建立了轮换与不轮换两种情况下供应商的期望收益模型。通过实例分析,提出了国家应急物资储备管理部门在不同时段的策略建议,解决了传统储备模式下"死储"的问题,为寄售模式在应急物资储备体系中的推广应用提供了理论支撑。  相似文献   
1000.

The household sector is a major driver of energy consumption and greenhouse gas (GHG) emissions. However, most existing studies have only estimated households’ carbon footprint from their expenditures. Households’ daily activity time, a scarce resource that limits and determines their consumption behavior, has rarely been integrated into the estimation. Incorporating the daily time-use patterns should thus provide a more practical perspective for mitigation policies aiming at promoting sustainable household lifestyles. In this study, by linking household time-use data and expenditure data of Japan, the carbon footprint and the GHG intensity of time of 85 daily household activities constituting the 24 hours in a day are estimated. Compared to the maximal 20-activity disaggregation in existing studies, our detailed 85-category disaggregation of daily time enables unprecedented details on the discrepancies between the carbon footprint from daily activities, many of which have previous been treated as one activity. Results indicate significant carbon mitigation potential in activities with a high GHG intensity of time, such as cooking, bathing, and mobility-related and activities. Average daily GHG emissions were also found to be higher on weekends as time-use patterns shift from paid work to free-time activities, highlighting the need for mitigation strategies on a weekly scale.

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