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991.
992.
This paper examines the issue of ancillary benefits by linking sulfur dioxide (SO2) emission to CO2 emission using a panel of 29 Chinese provinces over the period 1995–2007. In the presence of non-stationarity and cointegrating
properties of these two data series, this paper applies the panel cointegration techniques to examine both the long-run and
short-run elasticities of SO2 with respect to CO2. The major findings are that: (1) there exhibits a stable long-run equilibrium relationship between the SO2 and CO2 emission with the long-run elasticity being 2.15; (2) there exists a short-run relationship between these two emissions with
the short-run elasticity being 0.04. In addition, following an exogenous shock that causes a deviation from the long-run equilibrium,
it would take approximately 15 years for SO2 emission to revert toward the long-run equilibrium path with an average annual convergence rate of 6.5%; (3) the derived
ancillary benefits that is generated from one metric ton of CO2 emission reduction, are 11.77 Yuan (approximately US1.7) in the short run and 196.16 Yuan (US 1.7) in the short run and 196.16 Yuan (US 30) in the long run. These
findings are not only crucial from the econometric modeling perspective, but also have important policy implications. 相似文献
993.
Tang X Chen J Wang WH Liu TW Zhang J Gao YH Pei ZM Zheng HL 《Environmental pollution (Barking, Essex : 1987)》2011,159(12):3784-3792
This study characterized the changes of nitric oxide (NO) production during the growth of Microcystis aerugrinosa, a cyanobacterium which usually cause cyanobacterial blooms. Results showed a drastic NO release accompanying with cell density and Chl-a content sharp rises when M. aerugrinosa grew from fifth day to sixth day. Moreover, high N:P ratio accelerated the cyanobacterial growth and NO burst. Sodium nitroprusside, an exogenous NO donor, promoted M. aerugrinosa growth with the optimal concentration of 0.1 mg/L. Experiments by supplementing with sodium nitrite and l-arginine demonstrated NO production in M. aerugrinosa cells was mainly through nitrate reductase (NR) pathway while minorly through NO synthase pathway. All these data suggested M. aerugrinosa produced increasing NO during its growth mainly by NR pathway, during which NO positively regulated the growth of M. aerugrinosa. 相似文献
994.
Wang H Ouyang Z Chen W Wang X Zheng H Ren Y 《Environmental pollution (Barking, Essex : 1987)》2011,159(8-9):2127-2137
Transpiration rates of six urban tree species in Beijing evaluated by thermal dissipation method for one year were correlated to environmental variables in heat, water, and pollutant groups. To sort out colinearity of the explanatory variables, their individual and joint contributions to variance of tree transpiration were determined by the variation and hierarchical partitioning methods. Majority of the variance in transpiration rates was associated with joint effects of variables in heat and water groups and variance due to individual effects of explanatory group were in comparison small. Atmospheric pollutants exerted only minor effects on tree transpiration. Daily transpiration rate was most affected by air temperature, soil temperature, total radiation, vapor pressure deficit, and ozone. Relative humidity would replace soil temperature when factors influencing hourly transpiration rate was considered. 相似文献
995.
996.
Jian-Guang Wu Xiang-Yu Meng Xiao-Meng Liu Xian-Wei Liu Zhi-Xia Zheng De-Qian Xu Guo-Ping Sheng Han-Qing Yu 《Environmental management》2010,46(4):610-617
Life cycle assessment (LCA) was applied to analyze a food-processing wastewater treatment plant and investigate the economic
and environmental effects of the plant. With the long-term operational data of this plant, an inventory of relative inputs,
e.g., flow rate, chemical oxygen demand (COD), and suspended solids, etc., and outputs of the plant, e.g., effluent COD and
suspended solids, methane production, etc., was compiled. The potential environmental effects associated with those inputs
and outputs were evaluated, and the results of the inventory analysis and impact assessment phases of the plant were interpreted.
One feature of this study was the assessment of the treatment plant based on both energy and material flows. Another feature
was the establishment of an assessment model with an integration of plant operating parameters, system recognition and grey
relation. The analytical results are helpful for the design and operation of wastewater treatment plants. 相似文献
997.
This study utilizes remote sensing derived forest aboveground biomass (AGB) estimates and ownership information obtained from
the Protected Areas Database (PAD), combining landscape analyses and GIS techniques to demonstrate how different ownerships
(public, regulated private, and other private) relate to the spatial distribution of AGB in New England states of the USA.
“Regulated private” lands were dominated by lands in Maine covered by a Land Use Regulatory Commission. The AGB means between
all pairs of the identified ownership categories were significantly different (P < 0.05). Mean AGB observed in public lands (156 Mg/ha) was 43% higher than that in regulated private lands (109 Mg/ha), or
30% higher than that of private lands as a whole. Seventy-seven percent of the regional forests (or about 9,300 km2) with AGB >200 Mg/ha were located outside the area designated in the PAD and concentrated in western MA, southern VT, southwestern
NH, and northwestern CT. While relatively unfragmented and high-AGB forests (>200 Mg/ha) accounted for about 8% of total forested
land, they were unevenly proportioned among the three major ownership groups across the region: 19.6% of the public land,
0.8% of the regulated private land, and 11.0% of the other private land. Mean disturbance rates (in absolute value) between
1992 and 2001 were 16, 66, and 19 percent, respectively, on public, regulated private, and other private land. This indicates
that management practices from different ownerships have a strong impact on dynamic changes of landscape structures and AGB
distributions. Our results may provide insight information for policy makers on issues regarding forest carbon management,
conservation biology, and biodiversity studies at regional level. 相似文献
998.
超声波降解水溶液中对二氯苯 总被引:1,自引:0,他引:1
采用超声波降解含对二氯苯(p-DCB)的溶液,研究了p-DCB降解的动力学和影响因素.结果表明:(1)超声波降解水溶液中的p-DCB,随着p-DCB初始浓度的增加降解率减小;p-DCB的超声波降解反应符合表观一级动力学规律.(2)增大超声波频率和功率以及双频率联合使用可以增大p-DCB的降解率和一级反应速率常数.(3)弱酸性或中性环境更有利于p-DCB的降解进行.(4)反应时的搅拌和自由基清除剂的投加都降低了p-DCB的降解率,这是因为超声波降解时空化气泡内的热裂解和自由基作用的削弱.(5)在单一体系中,p-DCB比对氯苯胺(p-ClA)更易降解.在混合体系中,p-ClA的加入没有显著降低p-DCB的去除效果,因为亲水的p-ClA不易挥发,难以进入空化气泡竞争能量和自由基,其存在对空化气泡内混合气体的比热容比影响较小;而p-DCB的存在却明显降低了p-ClA的降解效果,因为疏水的p-DCB易挥发进入空化气泡竞争能量和自由基,并降低混合气体的比热容比. 相似文献
999.
硝酸盐对富磷剩余污泥厌氧消化的影响试验 总被引:2,自引:1,他引:1
以某采用 A/O 生物除磷工艺水质净化厂排出的富磷剩余污泥为研究对象,利用棕色消化瓶设计了 4 组厌氧消化试验,通过向其中投加NaNO3,考察硝酸盐对污泥消化过程的影响.结果表明,硝酸盐的存在导致 VSS 平均变化速率比空白样快 28.09 mg/(L·d),并且对污泥消化过程中的产甲烷阶段有一定的抑制作用;当硝酸盐存在时,厌氧氨氧化作用的发生导致上清液中的 N-NH4 变化速率减慢,硝酸盐对污泥消化过程中磷的释放有明显的抑制作用,当硝酸盐浓度高于 60 mg/L时,抑制作用明显. 相似文献
1000.