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11.
本文介绍了国外近二十年来专家系统在废水生物处理工艺控制领域的应用及开发的典型系统,分析了废水生物处理工艺难于控制的原因、各类系统的结构和特点及目前废水处理专家系统的不足,探讨了废水生物处理专家系统今后应深入研究的问题及方向 相似文献
12.
应用灰色系统理论,根据江苏省地震工程研究院的地震科技开发资料,分别以项目负责人的年龄、学历、职称、职务、学科作为比较数列,对年度内完成的实际合同额进行了多因素灰色关联分析,排出了关联序。研究结果客观地揭示了开发能力与人的各种因素——年龄、学历、职称、职务、学科之间的相互关系,为市场经济条件下,地震科技人才的开发、培养和应用,提供了科学依据。 相似文献
13.
Social and mating system of cooperatively breeding laughing kookaburras (Dacelo novaeguineae) 总被引:4,自引:0,他引:4
DNA fingerprinting was combined with field observations over four breeding seasons to investigate the social structure and
mating system of the laughing kookaburra (Dacelo novaeguineae). Groups comprised a socially dominant pair and up to six helpers of either sex. Helpers were always recruited from young
hatched in the group. Territorial inheritance, which is a feature of other cooperative breeders and an oft-cited benefit of
philopatry, did not occur. Helpers only attained dominant status in an established group by dispersing into a vacant dominant
position in that group. However, helpers could also form new groups by excising a new territory, often through a ”budding”
process. The mating system was overwhelmingly monogamous. There were no cases of extra-group parentage in a sample of 140
nestlings; within groups of three or more birds, dominance predicted parentage almost perfectly (99.2% of 129 nestlings),
irrespective of whether helpers in the group were related to one or both dominant birds. This is contrary to predictions from
models of reproductive skew, possibly because they currently fail to incorporate the willingness of females to share reproduction
among males.
Received: 15 May 1999 / Received in revised form: 2 November 1999 / Accepted: 6 November 1999 相似文献
14.
In the meerkat (Suricata suricatta), a cooperative mongoose, pups follow potential feeders while the group is foraging and emit incessant calls when soliciting
food from them. In contrast to a ’stationary’ brood of chicks, in which nestlings are fed at a fixed location, meerkat pups
are ’mobile’ and become spread out. The question arises whether meerkat pups that experience different constraints to those
facing chicks have evolved similar begging strategies. This paper describes the vocalisations that meerkat pups emit in the
context of begging and investigates the influence of these calls on food allocation by older group members and on the behaviour
of littermates. Meerkat pups use two types of calls when soliciting food from a potential feeder. The most common is a ’repeat’
call, which pups emit continuously when following an older forager over several hours a day. In addition, when a potential
feeder finds a prey item, the pups next to it emit a bout of calls with increased calling rate, amplitude and fundamental
frequency, termed ’high-pitched’ calls. Observations, together with playback experiments, showed that more prey was allocated
to pups that called longer and more intensely. The pup closest to a feeder was almost always fed. The probability of emitting
high-pitched calls did not depend on the time since a pup had received food, and the change from repeat to high-pitched calls
occurred suddenly. The main function of the high-pitched call, therefore, does not appear to be to signal a pup’s hunger state.
More likely, the two calls, in the context of begging, may be an adaptation to energetic constraints in a mobile feeding system.
Pups, which are dispersed during foraging, may emit repeat calls over long periods to prevent potential feeders from eating
all the prey themselves. At the moment a potential feeder finds prey, pups may give the more intense high-pitched calls to
direct feeders to bring the food item to them and not to a littermate. Therefore, unlike the stationary feeding system where
chicks emit one type of begging call when the feeder approaches the nest, meerkats, with a mobile feeding system, have evolved
two discrete types of vocalisations in the context of begging.
Received: 22 November 1999 / Revised: 1 July 2000 / Accepted: 17 July 2000 相似文献
15.
T. Lubjuhn Wolfgang Winkel Jörg Thomas Epplen Jörg Brün 《Behavioral ecology and sociobiology》2000,48(1):12-17
One of the most interesting aspects of the mating system of pied flycatchers is the regular occurrence of polygyny. Here we
present data on the reproductive success of polygynously paired pied flycatcher males compared to monogamous males based on
paternity analyses through DNA fingerprinting. Males paired with two females suffered a higher loss in reproductive output
per female compared to monogamous males due to (1) a greater proportion of unhatched eggs in their broods, (2) greater nestling
mortality and (3) a greater probability of being cuckolded. Nevertheless, the number of fledglings was significantly greater
for polygynous males. Based on the number of nestlings that returned for subsequent breeding seasons, however, the reproductive
success of monogamous and polygynous males did not differ significantly. These data raise the question as to why males attempt
polygyny.
Received: 16 August 1999 / Received in revised form: 15 March 2000 / Accepted: 18 March 2000 相似文献
16.
17.
生物过滤技术在大气污染控制中的应用 总被引:6,自引:0,他引:6
周琪 《城市环境与城市生态》1998,11(1):17-21
生物过滤是控制大气污染的经济有效技术,具有较好的发展前景。本文介绍了生物过滤技术处理废气的研究,应用历史,现状,和生物过滤理论,分析了工艺的使用范围,设计及运行控制要点,列举了应用的范例。 相似文献
18.
19.
Comprehensive temperature monitoring in an in-vessel forced-aeration static-bed composting process 总被引:6,自引:0,他引:6
Masafumi Tateda Le Duc Trung Nguyen Viet Hung Michihiko Ike Masanori Fujita 《Journal of Material Cycles and Waste Management》2002,4(1):62-69
Comprehensive temperature monitoring was done in an in-vessel forced-aeration static-bed composting process using sewage sludge.
The three layers that divided the compost pile horizontally showed different temperature distributions. The temperature of
the top layer appeared not to be influenced by the ambient temperature. The temperature of the center area of the top layer
was taken to be the representative temperature for evaluating composting start-up performance. The temperature of the bottom
layer was strongly influenced by the ambient temperature, and the temperature of the center area of the bottom layer was taken
to be the representative temperature for pathogen control as it was the minimum temperature in the reactor. Composting start-up
performance was influenced by several factors when the ambient temperature was either below or above 20°C. When the ambient
temperature was below 20°C, the time taken to reach 65°C (T
65) was influenced by the temperature of inflowing air, but when the temperature was higher than 20°C, it was influenced by
the ratio of sewage sludge to seed compost (F/S). T
65 was least when F/S was 1–2.
Received: January 9, 2001 / Accepted: October 10, 2001 相似文献
20.