全文获取类型
收费全文 | 388篇 |
免费 | 8篇 |
国内免费 | 40篇 |
专业分类
安全科学 | 29篇 |
废物处理 | 18篇 |
环保管理 | 37篇 |
综合类 | 140篇 |
基础理论 | 53篇 |
污染及防治 | 111篇 |
评价与监测 | 26篇 |
社会与环境 | 19篇 |
灾害及防治 | 3篇 |
出版年
2024年 | 2篇 |
2023年 | 5篇 |
2022年 | 5篇 |
2021年 | 9篇 |
2020年 | 8篇 |
2019年 | 5篇 |
2018年 | 7篇 |
2017年 | 17篇 |
2016年 | 11篇 |
2015年 | 16篇 |
2014年 | 17篇 |
2013年 | 34篇 |
2012年 | 17篇 |
2011年 | 20篇 |
2010年 | 29篇 |
2009年 | 24篇 |
2008年 | 18篇 |
2007年 | 20篇 |
2006年 | 50篇 |
2005年 | 12篇 |
2004年 | 19篇 |
2003年 | 15篇 |
2002年 | 8篇 |
2001年 | 8篇 |
2000年 | 9篇 |
1999年 | 6篇 |
1998年 | 5篇 |
1997年 | 9篇 |
1996年 | 2篇 |
1995年 | 4篇 |
1994年 | 2篇 |
1993年 | 2篇 |
1992年 | 1篇 |
1991年 | 5篇 |
1990年 | 2篇 |
1987年 | 1篇 |
1985年 | 1篇 |
1984年 | 1篇 |
1981年 | 4篇 |
1980年 | 4篇 |
1979年 | 2篇 |
排序方式: 共有436条查询结果,搜索用时 15 毫秒
311.
Hong Kong, lying just below the Tropic of Cancer (22°17′N, 114°09′E), experiences a strongly seasonal environment, with a
cool almost temperate winter and a hot, tropical, summer. Histological sectioning of the gonads of the high-shore barnacle,
Chthamalus malayensis Pilsbry, showed a seasonal trend in the development of its reproductive organs. Four stages of female gonad development were
identified according to the cell types present: post-spawning, resting, growth and mature stages. The female gonad was mature
from April to November, which was related to seawater temperatures, and entered a resting phase from December to March. Although
the male gonad showed a seasonal developmental trend and reached maximum maturity in summer, the seminal vesicles were full
of spermatozoa and functional throughout the year. The reproductive season of this species is therefore solely dependant upon
the maturity of the female gonad. The estimated maximum number of broods per year was up to 10 and the maximum number of eggs
produced per brood can reach 3,000 eggs. The minimum size for female gonad maturity was 6 mm rostro-carinal diameter (RCD)
at which size, the barnacles were ~6-month old. Sperm production occurred at a smaller size (2 mm=2-month old). Compared with
Chthamalus montagui and Chthamalus stellatus from temperate regions, C. malayensis produced a greater number of broods per year, had a longer reproductive period and faster gonad development. Chthamaloid
barnacles in tropical regions may, therefore, invest more energy per year in reproduction during their life span. Contrary
to the seasonal gonad developmental pattern of C. malayensis in the present study, however, C. malayensis in Singapore (which experiences only slight seasonal variation) had mature female and male gonads throughout the year, further
supporting the strong role of climatic conditions effecting the reproductive biology of barnacles. 相似文献
312.
Sihai Li Huang Shin Ngew S.O. Hardy Chan Siu Choon Ng Hian Kee Lee T.S. Andy Hor 《Environmental monitoring and assessment》1997,44(1-3):481-485
The aim of this study is to develop a catalytic method which has advantages over current method to detoxify and degrade environmentally harmful polychlorinated biphenyls (PCBs). A variety of catalysts have been employed in a preliminary study on 1,4-dibromobenzene and 4,4-dibromobiphenyl which may be considered to represent simple analogues of PCBs. The most satisfactory catalysts are those involving [Pd(dppf)] [dppf = 1,1-bis(diphenylphosphino)ferrocene], generated in situ from PdCl2(dppf) or Pd(dppf)2. In the presence of the reducing reagent, namely NaBH4, debromination has been achieved at relative mild conditions with high product yields (> 70%). Thus, our results indicate the possibility of dechlorination of PCBs with such catalysts. 相似文献
313.
Z. Chen G.H. Huang C.W. Chan L.Q. Geng J. Xia 《Environmental Modeling and Assessment》2003,8(4):323-334
Groundwater and soil contamination caused by light nonaqueous phase liquids (LNAPLs) spills and leakage in petroleum industry is currently one of the major environmental concerns in North America. Numerous site remediation technologies, generally classified as ex situ and in situ remediation techniques, have been developed and implemented to clean up the contaminated sites in the last two decades. One of the problems associated with ex situ remediation is the cost of operation. In recent years, in situ techniques have acquired popularity. However, the selection process of the desired techniques needs a large amount of knowledge. Insufficient expertise in the process may result in unnecessary inflation of expenses. In this study, petroleum waste management experts and Artificial Intelligence (AI) researchers worked together to develop an expert system (ES) for the management of petroleum contaminated sites. Various AI techniques were used to construct a useful tool for site remediation decision-making. This paper presents the knowledge engineering processes of knowledge acquisition, conceptual design, and system implementation in the project. The expert system was applied to a real-world case study and the results show that the expert system can generate desired remediation alternatives to assist decision-makers. The application case study constitutes partial validation of the prototype expert system. 相似文献
314.
微囊藻毒素(MCs)是由有毒蓝藻(尤其是铜绿微囊藻)产生的一类藻毒素,可对水生生物和人类健康造成严重危害,然而目前有关浮游动物对MC-LR胁迫的应激响应研究较为少见.因此,本文探究了微囊藻毒素MC-LR和温度对采自青海西宁的萼花臂尾轮虫(Brachionus calyciflorus)热激蛋白Hsp70水平的影响.结果表明,温度、MC-LR及其交互作用对萼花臂尾轮虫Hsp70含量具有显著影响.在各温度条件下,MC-LR均诱导了轮虫Hsp70水平的上调;虽然Hsp70的表达水平在低剂量MC-LR处理下上调不显著,但在高剂量MC-LR(6 mg·L-1)处理下上调却极为显著;另外,以24℃处理为对照组,在20和28℃温度胁迫下各MC-LR处理组轮虫的Hsp70含量均显著增加,但16℃实验组与24℃对照组间未见显著差异,这可能与诱导轮虫Hsp70表达的环境温度阈值或机体对低温环境的长期适应性进化和调节机制有关. 相似文献
315.
In this study, a synthetic filter material with nutrients (PVA/peat/KNO3 composite bead) was developed for biofilteration. The optimal preparing condition was each of the peat and PVA aqueous solutions mixed with 6.4 g KNO3, and the minimum nitrogen content in the boric and phosphate aqueous solutions was 3.94 and 1.52 g-N/l, respectively. The equilibrium amount of inorganic nitrogen extracted by leaching from the prepared composite bead was between 7.95 and 8.21 mg N/g dry solid. The path of inorganic nitrogen extracted by leaching was the inorganic nitrogen dispersed in the peat phase firstly diffused into the outer PVA phase and then it diffused out of the bead surface for the A-type bead; and that was the inorganic nitrogen dispersed in both the peat and PVA phases simultaneously diffuses into the outer PVA phase and out of the bead surface, respectively, for the H-type bead. The microbial growth rate k
g of the H-type composite bead was higher than that of the A-type composite bead about 1.09–1.58 times, and the maximum value of k
g was at the H-type composite bead immersed in 0.384 M KNO3 aqueous solution. The percentage of removed VOCs retained at more than 98% during the biofilter operating 230 days as the composite bead immersed in KNO3 aqueous solution before packing. This composite bead bed was without the further addition of nutrients during the operating period. 相似文献
316.
Chao‐Hsien Liaw Liang‐Ching Chen Li‐Mei Chan 《Journal of the American Water Resources Association》2006,42(3):593-601
ABSTRACT: This work establishes an industrial water demand (IWD) model for a short term estimate, which considers water reuse technologies and discharge regulations, for the integrated circuit (IC) industry in northern Taiwan. Based on the optimization of an industrial water cost system, a computerized system dynamics model (SD model) is developed to generate individual firm IWD using data from year 2000. A market IWD is further constructed for 25 1C firms in the study area and is approximated by an inverse logistic curve. Analytical results demonstrate that price elasticity varies with water price in cases involving water reuse. 相似文献
317.
Chuk-ling Julian Lai Andrew Brennan Ho-mun Chan Julia Tao 《Journal of environmental psychology》2003,23(4):369-384
This paper extends prior research on risk perceptions in the West to the Hong Kong Chinese context by studying the nature of the responses of 229 Hong Kong Chinese to an adapted environmental appraisal inventory (EAI-C), which consisted of three scales with one related to the self and the other two related to the local and global environments, respectively. Results lent support to a local–global dichotomy: hazards were appraised to be more threatening in the global than the local context. Responses to the three-scale adaptation were factor analysed and three subscales were extracted for each of the EAI scales. As with findings reported in a previous study with an Irish sample, the subscales could be considered to represent techno-human, everyday-life and natural hazards. Results also indicated that Hong Kong Chinese appraised environmental hazards as more threatening than did Western samples surveyed in prior studies. This was most striking when hazards were appraised in relation to the self. Similar findings have also been reported in recent studies with Japanese samples. It was suggested that the accentuated threat to self observed in the current study might stem from a heightened sensitivity to environmental hazards in the Chinese people, which is determined by self-construction processes specific to Asian cultures. Using the EAI as a measurement for hazard appraisal may provide insights to how people from different cultures construe the impact of environmental hazards in various contexts. 相似文献
318.
Joanna P. Y. Chan Pei Rong Lau Ai Jie Tham Daiqin Li 《Behavioral ecology and sociobiology》2008,62(5):639-646
In experiments that comprised of three phases (fight, choice, and mating) under “seen” and “unseen” conditions, we examined
the effects of the outcomes of male–male contests and female eavesdropping on female mate choice and male mating success in
the fighting spider, Thiania bhamoensis (Salticidae). The results revealed female eavesdropping on agonistic interactions. Females that had watched an aggressive
interaction showed no distinctive preference for the winner over the loser, but they preferred the loser when they had not
observed a fight. Winners, however, achieved a greater mating success than did losers during the mating phase. Gaining access
to females was based on the insistence of the winners in courtship in terms of the number of quivers, rather than on the fighting
behavior of the males. Hence, the outcome of male–male contests may not be an important determinant of a male’s mating success
in T. bhamoensis. Instead, courtship display plays an important role in determining the success of male mating in this species. This study
also suggests that female mate preference may not be a good indicator of eventual female mate choice and male mating success.
Thus, a causal relationship between female mate preference and male mating success cannot be inferred.
Joanna P. Y. Chan, Pei Rong Lau, and Ai Jie Tham contributed equally. 相似文献
319.
Kara Chan 《The Environmentalist》2000,20(2):113-121
A systematic postal survey of 449 schools in Hong Kong (including kindergartens, primary and secondary schools) was conducted to investigate the use of environmental education teaching kits and to obtain feedback from teachers about the view and comments in using these kits. Results indicated that kindergartens used teaching kits more frequently than secondary and primary schools. Most of the schools found the existing teaching kits helpful. Appropriate content, updated information, attractiveness to students and inclusion of a teachers' guide were considered important criteria in deciding the use of the teaching kits. Good illustrations, quality production and appropriate duration for the class were considered important factors too. The tight teaching schedule was the major hindrance for secondary and primary schools in the use of the environmental teaching kits. However, the main hindrance for using environmental teaching kits in kindergartens was that they did not have sufficient copies. Hong Kong schools would like to see new teaching kits about waste recycling, energy conservation, green behaviour, air pollution, noise pollution, sewage treatment and wildlife endangering, focusing on Hong Kong and China. 相似文献
320.
Haiyan Yuan Jun Yao Kanaji Masakorala Fei Wang Minmin Cai Chan Yu 《Environmental science and pollution research international》2014,21(4):2724-2732
The pryene-degradation bacterium strain USTB-X was newly isolated from the polycyclic aromatic hydrocarbon (PAH)-contaminated soil in Beijing Coking Plant, China. The strain was identified as Acinetobacter with respect to its 16S rDNA and morphological and physiological characteristics. The strain was Gram-negative, non-mobile, non-acid-fast, and non-spore-forming, short rods in young culture and 0.8–1.6 μm in diameter and 1.2–2.5 μm long in the stationary phase of growth. Strain USTB-X could utilize pyrene, naphthalene, fluorene, phenanthrene, benzene, toluene, ethylbenzene, ethanol, methanol, and Tween 80 as sole source of carbon and energy. The strain could produce biosurfactants which enhanced the removal of pyrene and could remove 63 % of pyrene with an initial concentration of 100 mg·L?1 in 16 days without other substrates. Based on the intermediates analyzed by gas chromatography-mass spectrometry, we also deduced the possible metabolic pathway of strain USTB-X for pyrene biodegradation. Results indicated that the strain USTB-X had high potential to enhance the removal of PAHs in contaminated sites. 相似文献