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161.
Concentration level of heavy metals in the Great Wall Bay, Antarctica in austral summer 总被引:1,自引:0,他引:1
ConcentrationlevelofheavymetalsintheGreatWallBay,Antarcticainaustralsummer¥PuJiabin;FuYunna;LiZhongping(InstituteofMarineEnvi... 相似文献
162.
实验研究了海泊河废水及其河口区水体的光学性质以及溶解有机碳(DOC)浓度,分析了光吸收系数(aCDOM)、最大荧光强度与DOC的关系.结果表明,海水中aCDOM在1.81~3.51 m-1内,平均值为2.39 m-1;而废水样品的aCDOM在0.59~16.23 m-1内,平均值为3.35 m-1.海水中aCDOM、光吸收指数斜率系数(S)、最大荧光强度以及DOC浓度都小于废水中相应的参数.水体中aCDOM、最大荧光强度以及DOC浓度三者之间均存在较好的线性关系.胶州湾东部海区海水中CDOM主要来源于海泊河排放的废水,由于水动力和潮汐作用较强而很快扩散,它们的浓度很快降低,在海泊河附近海区没有明显的积累. 相似文献
163.
辽东湾近岸冰区生态环境初步调查研究 总被引:1,自引:0,他引:1
1996年1月26-31日,在辽东湾近岸冰区选设4个站位进行了一次内容较为全面的生态环境调查研究,其项目包括温度、盐度、pH、DO、COD、TOC、POC、营养盐、微生物、叶绿素、浮游植物、浮游动物和度栖动物。结果表明,辽东湾近岸冰区营养盐含量丰富,叶绿素a含量较低,存在一定数量的浮游生物。海水中硝酸盐、铵盐和磷酸盐含量均为冰中含量的1.5倍左右,海水中硅酸盐含量是冰的4.16倍,亚硝酸盐和叶绿素 相似文献
164.
165.
厦门西港表层沉积物中有机氯化合物的污染特征及变化趋势 总被引:13,自引:3,他引:13
利用GC-ECD对厦门西港1998年7月取得的8个站位表层沉积物中的18种有机氯农药(HCHs,DDTs)等和12种多氯联苯(PCBs)进行分析。其中有机氯农药的浓度范围ND(未检测出)-0.58ng/g(其中HCHs和DDTs的含量分别为ND-0.14ng/gND-0.06ng/g),多氯联苯的浓度为ND-0.32ng/g,与1986、1993年的厦门西港的分析结果相比较,污染程度明显降低;说明近年来的厦门的有机污染得到逐步控制,也与有机物随时间推移逐渐详解有关,分析表明多氯联苯和有机氯农药在厦门西港有着相似的分布特征。 相似文献
166.
167.
We carried out a field study of the plume discharged by a near-shore wastewater outfall near the Akashi Strait, Japan. Using
an Acoustic Doppler Current Profiler and a tow-body CTD, we measured the near-surface salinity and temperature fields in the
region throughout an M2 tidal cycle. We filtered the data in T–S space to remove water masses other than the wastewater, and then used the adiabatic
mixing assumption to calculate the concentration of wastewater in the far field of this plume. Averaging the T–S fields of
repeated surveys over a time period during which the tidal regime did not change substantially, allowed comparison of the
time-averaged plume with the analytical solution for a plume diffusing in both the horizontal and vertical dimensions. The
resulting vertical turbulent diffusion coefficients agreed well with those resulting from Thorpe scales determined via a vertically-profiling
CTD, as well as with the canonical value for open channel flow of D
z
= 0.067hu
*. The corresponding horizontal turbulent diffusion coefficients, however, were two orders of magnitude larger than those typically
observed in straight channels, and an order of magnitude larger than those observed in meandering rivers. This is likely a
result of enhanced horizontal mixing due to barotropic eddies generated by the interaction of strong tidal flow with headlands
and levees, as well as due to the time-varying nature of tidal flow, and baroclinic spreading of the buoyant wastewater plume. 相似文献
168.
We carried out a field study of a small river plume emptying into Osaka Bay near the Akashi Strait in western Japan, to understand
the fate of its urban-runoff-laden waters. As the river is weak compared to tidal currents, we find that the behavior of the
plume is strongly influenced by phasing between tidal stage and currents (a westward-traveling progressive tidal wave). When
the tidal stage rises, sea water floods up the river, and concentrated river effluent cannot be seen in Osaka Bay. During
most of the river’s ebb, a topographic eddy transports river effluent towards the energetic Akashi Strait, while strong vertical
shear in the tidal flow mixes the effluent with seawater. However, there is a short interval of time during which the direction
of tidal flow in the Strait changes direction and the magnitude of the current is weak. At this time, shear is weak enough
to allow a stratified plume of concentrated river water to form, and this plume is driven offshore, and into Osaka Bay, by
baroclinic circulation. A sewage outfall, which is located very close to the river mouth, is subjected to these same conditions
and therefore exhibits similar behavior. Understanding the relation between tidal phase and plume behavior will be useful
to Kobe City, as well as other cities in a similar environment, for minimizing the environmental effects of their wastewater
and non-point-source runoff. 相似文献
169.
170.
In 1994 the Countryside Council for Wales, the government nature conservation and countryside advisor in Wales, published
a consultation document on marine and coastal policy, and also commissioned research into the status of coastal zone management
(CZM) in the Principality. The research, undertaken by the University of Wales Cardiff, investigated CZM from an international,
national (U.K.) and Welsh perspective, concentrating on detailed case studies of three areas (including both urban and rural
coasts). Policy makers, managers, practitioners and users from all sectors were included in the study which established current
activity, identified problems and reviewe future plans. Interviews and questionnaire returns highlighted vital information
gaps at all levels. These ranged fom a lack of basic data (including scientific and technical), to a breakdown in communication
both within and between organisations, as well as a policy vacuum in both regional and central government. 相似文献