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61.
Biotechnological production of fuels and chemicals from renewable resources is an appealing way to move from the current petroleum-based economy to a biomass-based green economy. Recently, the feedstocks that can be used for bioconversion or fermentation have been expanded to plant biomass, microbial biomass, and industrial waste. Several microbes have been engineered to produce chemicals from renewable resources, among which Escherichia coli is one of the best studied. Much effort has been made to engineer E. coli to produce fuels and chemicals from different renewable resources. In this paper, we focused on E. coli and systematically reviewed a range of fuels and chemicals that can be produced from renewable resources by engineered E. coli. Moreover, we proposed how can we further improve the efficiency for utilizing renewable resources by engineered E. coli, and how can we engineer E. coli for utilizing alternative renewable feedstocks. e.g. C1 gases and methanol. This review will help the readers better understand the current progress in this field and provide insights for further metabolic engineering efforts in E. coli. 相似文献
62.
Elisabeth Hochschorner Göran Finnveden 《The International Journal of Life Cycle Assessment》2006,11(3):200-208
Goal, Scope and Background
Procurement in public and non-public organisations has the potential to influence product development towards more environmentally
friendly products. This article focuses on public procurement with procurement in Swedish defence as a special case. In 2003,
public procurement in Sweden was 28% of the GDP. In the Swedish defence sector the amount was 2% of the GDP. The total emissions
from the sector were of the same order of magnitude as from waste treatment (2% of Sweden's emissions). According to an appropriation
letter from the Ministry of Defence in 1998, the Swedish Armed Forces (SAF) and the Swedish Defence Materiel Administration
(FMV) are required to take environmental issues into consideration during the entire process of acquiring defence materiel.
Environmental aspects are considered today, but without a life-cycle perspective.
- The aims of this article are to recommend suitable tools for taking environmental concerns into account, considering a product's
life-cycle, in the procurement process for defence materiel in Sweden; to make suggestions for how these tools could be used
in the acquisition process; and to evaluate these suggestions through interviews with actors in the acquisition process. The
procurement process does not include aspects specific to Swedish defence, and it is therefore likely to be comparable to processes
in other countries.
Methods
The method involved a study of current literature and interviews with various actors in the acquisition process. The life
cycle methods considered were quantitative Life Cycle Assessments, a simplified LCA-method called the MECO method and Life
Cycle Costing (LCC).
Results and Discussion
Methodology recommendations for quantitative LCA and simplified LCA are presented in the article, as well as suggestions on
how to integrate LCA methods in the acquisition process. We identified four areas for use for LCA in the acquisition process:
to learn about environmental aspects of the product; to fulfil requirements from customers; to set environmental requirements
and to choose between alternatives. Therefore, tools such as LCAs are useful in several steps in the acquisition process.
Conclusion
From the interviews, it became clear that the actors in the acquisition process think that environmental aspects should be
included early in the process. The actors are interested in using LCA methods, but there is a need for an initiative from
one or several of them if the method is to be used regularly in the process. Environmental and acquisition issues are handled
with very little interaction in the controlling and ordering organisation. An integration of environmental and acquisition
parts in these organisations is probably needed in order to integrate environmental aspects in general and life-cycle thinking
in particular. Other difficulties identified are costs and time constraints.
Recommendation and Perspective
In order to include the most significant aspects when procuring materiel, it is important to consider the whole life-cycle
of the products. Our major recommendation is that the defence sector should work systematically through different product
groups. For each product group, quantitative, traditional LCAs or simplified LCAs (in this case modified MECOs) should be
performed for reference products within each product group. The results should be an identification of critical aspects in
the life-cycles of the products. The studies will also form a database that can be used when making new LCAs. This knowledge
should then be used when writing specifications of what to procure and setting criteria for procurement. The reports should
be publicly available to allow reviews and discussions of results. To make the work more cost-effective, international co-operation
should be sought. In addition, LCAs can also be performed as an integrated part of the acquisition process in specific cases. 相似文献
63.
Gjalt Huppes Arjan de Koning Sangwon Suh Reinout Heijungs Lauran van Oers Per Nielsen Jeroen B. Guine 《Journal of Industrial Ecology》2006,10(3):129-146
For developing product policy, insight into the environmental effects of products is required. But available life-cycle assessment studies (LCAs) are hardly comparable between different products and do not cover total consumption. Input-output analysis with environmental extensions (EEIOA) of full consumption is not available for the European Union. Available country studies have a low sector resolution and a limited number of environmental extensions. This study fills the gap between detailed LCA and low-resolution EEIOA, specifying the environmental effects of household consumption in the European Union, discerning nearly 500 sectors, while specifying a large number of environmental extensions. Added to the production sectors are a number of consumption activities with direct emissions, such as automobile driving, cooking and heating, and a number of postconsumer waste management sectors. The data for Europe have been constructed by using the sparse available and coarse economic and environmental data on European countries and adding technological detail mainly based on data from the United States.
A small number of products score high on environmental impact per Euro and also have a substantial share of overall consumer expenditure. Several meat and dairy products, household heating, and car driving thus have a large share of the total environmental impact. Due to their sales volume, however, products with a medium or low environmental score per Euro may also have a substantial impact. This is the case with bars and restaurants, clothing, residential construction, and even a service such as telecommunications. The limitations in real European data made heroic assumptions necessary to operationalize the model. One conclusion, therefore, is that provision of data in Europe urgently needs to be improved, at least to the level of sector detail currently available for the United States and Japan. 相似文献
A small number of products score high on environmental impact per Euro and also have a substantial share of overall consumer expenditure. Several meat and dairy products, household heating, and car driving thus have a large share of the total environmental impact. Due to their sales volume, however, products with a medium or low environmental score per Euro may also have a substantial impact. This is the case with bars and restaurants, clothing, residential construction, and even a service such as telecommunications. The limitations in real European data made heroic assumptions necessary to operationalize the model. One conclusion, therefore, is that provision of data in Europe urgently needs to be improved, at least to the level of sector detail currently available for the United States and Japan. 相似文献
64.
This paper proposes a computer-based method for providing product designers with real-time environmental impact assessment. In this concurrent modeling approach, environmental experts build life-cycle models, define their interfaces, and publish them as distributed objects on the Internet. Traditional designers integrating these objects into their design models have access to the impact assessment methods provided by the environmental expert. In this paradigm, the focus shifts from providing techniques that let non-expert designers perform life-cycle impact assessments to tools that facilitate timely communication and information transfer between designers and appropriate environmental experts. Establishing real-time communication between the product design models and the environmental life-cycle models is the primary focus of this paper. Methods for establishing and maintaining the interaction between life-cycle and product design models are described. A beverage container design example illustrates how this collaborative approach can use environmental and traditional design goals to determine effective tradeoffs between design alternatives. 相似文献
65.
Robério C.S. Neves Allan T. Showler Ézio S. Pinto Cristina S. Bastos Jorge B. Torres 《Entomologia Experimentalis et Applicata》2013,146(2):276-285
Cotton pests damaging fruiting bodies (squares and young bolls) are difficult to control and their damage results in direct yield loss. Small growers, with low technological inputs, represent a large portion of cotton growers worldwide comprising more than 76 countries; they rely mainly on cultural practices to counteract pest attack in their crops. Boll weevil, Anthonomus grandis Boheman (Coleoptera: Curculionidae), oviposition involves puncturing cotton squares and young bolls, causing abscission. We examined the impact on boll weevil population of collecting abscised cotton fruiting bodies and clipping plant terminals at 50% boll maturation in the field during two cotton‐growing seasons and under field cage conditions. Greatest numbers of damaged squares occurred ca. 117 days after planting and clipped plants resulted in reduction of abscised structures and adult boll weevils compared with non‐clipped plants, irrespective of cotton variety. Damaged young bolls were found ca. 128 days after planting in 2009 and 2011, but clipping had no effect. Numbers of boll weevils found in plants of the varieties BRS 201 and BRS Rubi (both in 2009) and BRS Rubi (in 2011) were, respectively, 13‐, 17‐, and 20‐fold greater when clipping plus collecting abscised fruiting bodies were not practiced. Furthermore, the average percentage of the boll weevil parasitoid Bracon vulgaris Ashmead (Hymenoptera: Braconidae) emerging from abscised and collected structures was similar between clipped and non‐clipped plant terminals in both seasons. Clipping plant terminals did not result in yield reduction and reduced adult boll weevil production. Collecting abscised reproductive structures, clipping plant terminals, and using both practices together reduced boll weevil populations by as much as 63, 57, and 79%, respectively, in cage trials. Thus, these practices cause significant impact on boll weevil populations and are feasible of adoption, especially for smallholder cotton growers. 相似文献
66.
Zhaoen Yang Chenxu Gao Yihao Zhang Qingdi Yan Wei Hu Lan Yang Zhi Wang Fuguang Li 《植物学报(英文版)》2023,65(2):548-569
Upland cotton is an important global cash crop for its long seed fibers and high edible oil and protein content.Progress in cotton genomics promotes the advancement of cotton genetics,evolutionary studies,functional genetics,and breeding,and has ushered cotton research and breeding into a new era.Here,we summarize high-impact genomics studies for cotton from the last 10 years.The diploid Gossypium arboreum and allotetraploid Gossypium hirsutum are the main focus of most genetic and genomic studi... 相似文献
67.
68.
Rebecca L. Taylor Mark S. Udevitz Chadwick V. Jay John J. Citta Lori T. Quakenbush Patrick R. Lemons Jonathan A. Snyder 《Marine Mammal Science》2018,34(1):54-86
The Pacific walrus (Odobenus rosmarus divergens) is a candidate to be listed as an endangered species under United States law, in part, because of climate change‐related concerns. While the population was known to be declining in the 1980s and 1990s, its recent status has not been determined. We developed Bayesian models of walrus population dynamics to assess the population by synthesizing information on population sizes, age structures, reproductive rates, and harvests for 1974–2015. Candidate models allowed for temporal variation in some or all vital rates, as well as density dependence or density independence in reproduction and calf survival. All selected models indicated that the population underwent a multidecade decline, which began moderating in the 1990s, and that annual reproductive rate and natural calf survival rates rose over time in a density‐dependent manner. However, selected models were equivocal regarding whether the natural juvenile survival rate was constant or decreasing over time. Depending on whether juvenile survival decreased after 1998, the population growth rate either increased during 1999–2015 or stabilized at a lesser level of decline than seen in the 1980s. The probability that the population was still declining in 2015 ranged from 45% to 87%. 相似文献
69.
70.
80年代中后期以来,我省稻瘿蚊年度成灾频率高,发生危害重。造成大发生主要原因是耕作制度改变、气候条件适台、咀及栽培管理、天敌因素影响等。近几年通过组织实施以农业生态防治为基础,加上科学用药等综合治理措施,取得了良好防治效果。 相似文献