全文获取类型
收费全文 | 141篇 |
免费 | 1篇 |
专业分类
安全科学 | 14篇 |
废物处理 | 2篇 |
环保管理 | 15篇 |
综合类 | 17篇 |
基础理论 | 52篇 |
污染及防治 | 30篇 |
评价与监测 | 4篇 |
社会与环境 | 7篇 |
灾害及防治 | 1篇 |
出版年
2024年 | 1篇 |
2022年 | 2篇 |
2021年 | 1篇 |
2020年 | 3篇 |
2018年 | 3篇 |
2017年 | 3篇 |
2015年 | 2篇 |
2014年 | 8篇 |
2013年 | 11篇 |
2012年 | 4篇 |
2011年 | 13篇 |
2010年 | 5篇 |
2009年 | 12篇 |
2008年 | 7篇 |
2007年 | 7篇 |
2006年 | 12篇 |
2005年 | 3篇 |
2004年 | 4篇 |
2003年 | 5篇 |
2002年 | 5篇 |
2001年 | 5篇 |
2000年 | 3篇 |
1999年 | 1篇 |
1998年 | 5篇 |
1997年 | 1篇 |
1995年 | 2篇 |
1992年 | 3篇 |
1989年 | 1篇 |
1986年 | 1篇 |
1979年 | 2篇 |
1978年 | 2篇 |
1977年 | 1篇 |
1976年 | 1篇 |
1965年 | 1篇 |
1954年 | 1篇 |
1932年 | 1篇 |
排序方式: 共有142条查询结果,搜索用时 234 毫秒
1.
Rossi Sebastian Dario Barros Agustina Walden-Schreiner Chelsey Pickering Catherine 《Ambio》2020,49(6):1146-1160
Ambio - Social media images are a novel source of data to assess how people view and value the environment. Access to these images is often free, the volume and spread of images is expanding... 相似文献
2.
Thomas Abeli Sarah Dalrymple Sandrine Godefroid Andrea Mondoni Jonas V. Müller Graziano Rossi Simone Orsenigo 《Conservation biology》2020,34(2):303-313
The alarming current and predicted species extinction rates have galvanized conservationists in their efforts to avoid future biodiversity losses, but for species extinct in the wild, few options exist. We posed the questions, can these species be restored, and, if so, what role can ex situ plant collections (i.e., botanic gardens, germplasm banks, herbaria) play in the recovery of plant genetic diversity? We reviewed the relevant literature to assess the feasibility of recovering lost plant genetic diversity with using ex situ material and the probability of survival of subsequent translocations. Thirteen attempts to recover species extinct in the wild were found, most of which used material preserved in botanic gardens (12) and seed banks (2). One case of a locally extirpated population was recovered from herbarium material. Eight (60%) of these cases were successful or partially successful translocations of the focal species or population; the other 5 failed or it was too early to determine the outcome. Limiting factors of the use of ex situ source material for the restoration of plant genetic diversity in the wild include the scarcity of source material, low viability and reduced longevity of the material, low genetic variation, lack of evolution (especially for material stored in germplasm banks and herbaria), and socioeconomic factors. However, modern collecting practices present opportunities for plant conservation, such as improved collecting protocols and improved cultivation and storage conditions. Our findings suggest that all types of ex situ collections may contribute effectively to plant species conservation if their use is informed by a thorough understanding of the aforementioned problems. We conclude that the recovery of plant species currently classified as extinct in the wild is not 100% successful, and the possibility of successful reintroduction should not be used to justify insufficient in situ conservation. 相似文献
3.
Angelo Rossi Giacomo Lamonaca Alessia Santucci Silvano Tosti 《International Journal of Greenhouse Gas Control》2011,5(3):521-530
Pd-based membranes have been studied for pure hydrogen separation from syngas: in particular, a mathematical model of a Pd membrane for hydrogen separation has been developed.This model can be used in process and assessment studies of the parameters which characterize the mass transfer phenomena (such as: hydrogen permeability, surface coverage and limiting step). By coupling the permeation and water gas shift reaction kinetics, it can also be used to evaluate the performances of the membrane reactor. Further, it can be helpful to evaluate the best assembly and sizing of a H2/CO2 separation system.The model takes into account the kinetics of H2 adsorption/desorption on Pd surface, the H2 permeation into the palladium bulk and in the porous layer, and the kinetics of CO, CO2, H2O, O2, H2S competitive adsorption/desorption on Pd surface. It is also comprehensive of flux equations and bulk mass, momentum and energy balance.The results released by the model were compared to the experimental data during both the transient phase and the steady state conditions. A satisfactory agreement between model and experimental data was found. 相似文献
4.
Kitta Rossi 《Safety Science》1995,20(2-3)
In 1990 the Scientific Committee on Occupational Health Nursing (SCOHN) of the International Commission on Occupational Health (ICOH) carried out a survey on the education of occupational health nurses (OHN) in various countries. A questionnaire with 23 questions was mailed to 50 countries.Replies were received form altogether 37 countries (74%). The length of the general nursing education varies from two to five years, being three years in 21 countries. In two European countries it is less than three years.Some special training in occupational health is included in the general nursing education in 14 countries. However, the length of this training varies considerably. The special training is the longest in Denmark, Finland and Norway.According to the answers, special postgraduate courses are organized in 21 countries. Training in occupational health is also included in the public health nursing education of 12 countries.University level programs on occupational health nursing are available in eight countries. Joint education on occupational health at university level has been organized for various professionals in 13 countries. The length of this education varies greatly from some months to several years. In four countries the length of this joint education is one academic year.General nursing education is the basic requirement for occupational health nurses in most of the countries surveyed. However, training in occupational health is not included in this education in most of the countries. Special postgraduate courses in occupational health are organized in 21 countries to OHNs who are employed in Occupational Health Services. There is an urgent need to develop the education of OHNs in most countries surveyed. 相似文献
5.
Since the end of the 1970s, the southern European countries have shown an exceptional reduction in fertility rate. From the
highest levels among the developed nations, these countries dropped beneath the substitution rate level: in Greece there is
an average of about 1.5 children per woman, and Italy (starting three to four years ago), with 1.3 children per woman, is
now the country with the lowest fecundity rate in the world. Land-use planning in southern European small islands therefore
requires substantial revision. In the areas where western civilization began, which are highly populated and have a long history,
cultural and ethnic aspects of tradition are fundamental to environmental management and to the defense of historical heritage.
They also place a strong value on sustaining tourism, the most relevant economic activity, that allows them to survive and
maintain a high welfare level. For some decades they have had populations with a marked presence of young people and high
emigration rates, but now they are fast becoming dominated by the elderly and must prepare for a period of fast reduction
in youth of the workforce, while the peripheral areas of Asia and Africa are entering a sudden demographic growth phase.
The demographic structure has also been deeply altered both by previous migrations and by random variations, as usually happens
in all small communities. Social services for younger and older people have had to be adapted rapidly, reorganizing high-school
management, hospital and health-care structures, in-house assistance, and so on. There is a need to rethink the job market
and favor the immigration of highly specialized workers, which is a necessity for technical evolution. Sustainable development
is constrained nowadays not only by the scarcity of natural resources, but also by the quality and quantity of human resources.
Proper policies for population and land-use planning are highly correlated factors; they have to be considered with respect
of these new, rapid demographic changes. 相似文献
6.
The impact of dense traffic on the breeding success in pied flycatchers (Ficedula hypoleuca) was studied using roadside nest-boxes. Nest site selection and breeding success of flycatchers were observed in relation to the distance from the road. The number of occupied territories was no higher closer to the road than it was deeper inside the forest. The distance to the road had no effect on the laying date, clutch size, or brood size. However, nests closer to the road were more likely to fail at the chick stage. The number of broods that were closer to roads and were lost completely was significantly higher than those further away. As a consequence, the number of fledglings per breeding attempt decreased closer to roads. The nestlings typically died as older chicks when the parent birds were providing them with maximum quantities of food. A possible reason for the declining reproductive success was the traffic-related mortality of parent birds, as weather conditions were not especially adverse for raising healthy offspring. 相似文献
7.
Specifically designed benthic chambers have been used to test whether the exposure for 48 hrs to polluted Lake Orta sediments could affect survival and reproduction behaviour of Daphnia obtusa and Echinogammarus stammeri. In situ results have been coupled to lab testing with Microtox, seed germination and root elongation (Lactuca sativa, Cucunris sativus, Lepidium sativum), and invertebrates (Daphnia obtusa, D. magna, E,. stammeri) acute toxicity tests.The technique and results here reported indicate the utility of in situ testing and suggest that under certain conditions this kind of test may be more realistic (avoiding sample manipulation in the lab) than traditional laboratory toxicity tests. 相似文献
8.
Genetic divergence and phylogenetic inferences in five species of Mugilidae (Pisces: Perciformes) 总被引:4,自引:0,他引:4
Allozyme electrophoresis was used to compare the genetic divergence of global populations of Mugil cephalus Linnaeus, 1758 and two congeneric [M.␣curema Cuvier & Valenciennes, 1836; M. gyrans (Jordan & Gilbert, 1885)] and two more distantly related [Liza ramada (Risso, 1826); Xenomugil thoburni (Jordan & Starks, 1896)] species on the basis of 18 enzyme loci. The amount of genetic divergence among the species examined
is in agreement with their present systematic status, the differences being larger among non-congeneric species than among
species of the same genus. Intraspecific genetic distances in M. cephalus (average Nei's D= 0.154), although higher than those reported for conspecific populations of fish, appear to be small when compared to the
interspecific values among mugilid species (0.821 ≤ Nei's D ≤ 1.744). Phylogenetic trees obtained by genetic distance methods and discrete character parsimony analysis were of similar
topology, except for the relationships within the genus Mugil and for the arrangement of M. cephalus populations.
Received: 7 April 1997 / Accepted: 4 February 1998 相似文献
9.
10.
Development of the Spatial Rainfall Generator (SRGEN) for the Agricultural Policy/Environmental Extender Model
下载免费PDF全文
![点击此处可从《Journal of the American Water Resources Association》网站下载免费的PDF全文](/ch/ext_images/free.gif)
Jaehak Jeong Jimmy R. Williams Colleen G. Rossi Robin A. Taylor Xiuying Wang William E. Fox 《Journal of the American Water Resources Association》2015,51(1):154-167
Accurate spatial representation of climatic patterns is often a challenge in modeling biophysical processes at the watershed scale, especially where the representation of a spatial gradient in rainfall is not sufficiently captured by the number of weather stations. The spatial rainfall generator (SRGEN) is developed as an extension of the “weather generator” (WXGEN), a component of the Agricultural Policy/Environmental eXtender (APEX) model. SRGEN generates spatially distributed daily rainfall using monthly weather statistics available at multiple locations in a watershed. The spatial rainfall generator as incorporated in APEX is tested on the Cowhouse watershed (1,178 km2) in central Texas. The watershed presented a significant spatial rainfall gradient of 2.9 mm/km in the lateral (north‐south) directions based on four rainfall gages. A comparative analysis between SRGEN and WXGEN indicates that SRGEN performs well (PBIAS = 2.40%). Good results were obtained from APEX for streamflow (NSE = 0.99, PBIAS = 8.34%) and NO3‐N and soluble P loads (PBIAS ≈ 6.00% for each, respectively). However, APEX underpredicted sediment yield and organic N and P loads (PBIAS: 24.75‐27.90%) with SRGEN, although its uncertainty in output was lower than WXGEN results (PBIAS: ?13.02 to ?46.13%). The overall improvement achieved in rainfall generation by SRGEN is demonstrated to be effective in the improving model performance on flow and water quality output. 相似文献