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231.
SRDAAR-QNPP:a computer code system for the real-timedose assessment of an accident releasefor Qinshan Nuclear Power Plant 总被引:2,自引:0,他引:2
SRDAAR-QNPP:acomputercodesystemforthereal-timedoseassessmentofanaccidentreleaseforQinshanNuclearPowerPlantHuErbang;WangHan(Ch... 相似文献
232.
本文以90年代中国地质大学档案工作与计算机技术的结合尚未形成整体为例。着重论述了实现馆藏资料计算机,提高中文信息含量,加强信息开发和管理工作中应注意的问题,从而发挥丰富的馆藏优势,促进信息服务产业的大力发展,加速我国“信息高速公路”的建议。 相似文献
233.
本文介绍了采用VisualBasic4.0建立的云南省污染治理数据库管理系统及其系统功能。实际应用,该系统具有使用方便、界面友好,易学易用等特点。 相似文献
234.
本文以“区域工业污染源数据库应用系统”为例,以数据库的概念结构设计、逻辑结构设计为重点,并引入连接矩阵等工具,从数据库设计方法学角度进行了初步探讨。 相似文献
235.
随着人口的增长,固体废物对于环境的污染越来越大,而科学技术的飞速发展,导致了电脑设备更新换代越来越快.本文分析了废旧电脑设备的环境危害和主要特点,资源化回收利用方法和回收程序,对比分析不同国家对待废旧电脑设备所采取的政策,然后详细介绍了我国废旧电脑设备管理与回收利用对策,其根本解决对策是加强立法、强化管理、健全回收网络和依靠科技进步. 相似文献
236.
Kazuhiko Sakamoto Katsunori Kimijima Tadao Suzuki Masahiro Uchiyama Yoshikazu Hashimoto Hisao ohta Yasuaki maeda Nobutoshi Horiuchi Shin Suzuki 《环境科学学报(英文版)》1990,(1)
The conversion rates of SO2 to SO42- and NO2 to HNO3+NO3- are estimated from the field-data obtained in Beijing in summer, 1988. The results show that the conversion rate of NO2 is about four times as much as that of SO2; The conversion rates have a diurnal variation in a day. On the average, the rate of SO2 is estimated to be 4.7% h-1 during the daytime and 3.4% h-1 during the nighttime. Similarly, the rate of NO2 is estimated to be 17.2% h-1 and 12% h-1 respectively. 相似文献
237.
阐述了UT-2000B型微机防误装置在永安火电厂的技改背景,对装置原理、主要技术特点、操作异常处理及技改安装内容作了介绍,并提出了投运后应注意的问题。 相似文献
238.
北京晟德瑞公司组装的工控机被广泛应用在水质自动监测系统中,发挥了很大优势,由于能自动连续运行并可无人执守,能显示流程标识,帮助解决各种故障问题。在水质自动监测系统的运行中起到了重要作用。如何维护好工控机的软件、硬件及相关的设备成为技术维护的重要组成部分。 相似文献
239.
In addition to heat production on the comb surface, honeybee workers frequently visit open cells (“gaps”) that are scattered
throughout the sealed brood area, and enter them to incubate adjacent brood cells. We examined the efficiency of this heating
strategy under different environmental conditions and for gap proportions from 0 to 50%. For gap proportions from 4 to 10%,
which are common to healthy colonies, we find a significant reduction in the incubation time per brood cell to maintain the
correct temperature. The savings make up 18 to 37% of the time, which would be required for this task in completely sealed
brood areas without any gaps. For unnatural high proportions of gaps (>20%), which may be the result of inbreeding or indicate
a poor condition of the colony, brood nest thermoregulation becomes less efficient, and the incubation time per brood cell
has to increase to maintain breeding temperature. Although the presence of gaps is not essential to maintain an optimal brood
nest temperature, a small number of gaps make heating more economical by reducing the time and energy that must be spent on
this vital task. As the benefit depends on the availability, spatial distribution and usage of gaps by the bees, further studies
need to show the extent to which these results apply to real colonies.
M. Fehler and M. Kleinhenz contributed equally to this work. 相似文献
240.
The Canary Islands are home to a guild of endemic, threatened bird-pollinated plants. Previous work has suggested that these
plants evolved floral traits as adaptations to pollination by flower specialist sunbirds, but subsequently, they appear to
have co-opted generalist passerine birds as sub-optimal pollinators. To test this idea, we carried out a quantitative study
of the pollination biology of three of the bird-pollinated plants, Canarina canariensis (Campanulaceae), Isoplexis canariensis (Veronicaceae) and Lotus berthelotii (Fabaceae), on the island of Tenerife. Using colour vision models, we predicted the detectability of flowers to bird and
bee pollinators. We measured pollinator visitation rates, nectar standing crops as well as seed-set and pollen removal and
deposition. These data showed that the plants are effectively pollinated by non-flower specialist passerine birds that only
occasionally visit flowers. The large nectar standing crops and extended flower longevities (>10 days) of Canarina and Isoplexis suggests that they have evolved a bird pollination system that effectively exploits these low frequency non-specialist pollen
vectors and is in no way sub-optimal. Seed set in two of the three species was high and was significantly reduced or zero
in flowers where pollinator access was restricted. In L. berthelotii, however, no fruit set was observed, probably because the plants were self-incompatible horticultural clones of a single
genet. We also show that, while all three species are easily detectable for birds, the orange Canarina and the red Lotus (but less so the yellow-orange Isoplexis) should be difficult to detect for insect pollinators without specialised red receptors, such as bumblebees. Contrary to
expectations if we accept that the flowers are primarily adapted to sunbird pollination, the chiffchaff (Phylloscopus canariensis) was an effective pollinator of these species. 相似文献