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21.
This paper provides the basis for a general model of catabolic metabolism for developing embryos and yolk-sac larvae of Atlantic cod (Gadus morhua L.). Yolk-dependent routine rates of oxygen consumption, ammonia excretion, and accumulation of ammonium ions were related to quantitative changes in contents of glucose, glycogen, lactate, free amino acids, proteins and lipid classes (lipid classes published separately) in order to determine the rate and sequence of catabolic substrate oxidation that occurs with development at 6.0°C, 34.5 S. The stoichiometric relation of the oxygen consumption and total ammonia production to substrate utilisation indicated that during the first 2 to 3 d of development, glycogen was the sole substrate of oxidative metabolism. After formation of the syncytium, free amino acids (75%) together with polar lipids (13%, mainly phosphatidyl choline) and neutral lipids (9%, mainly triacylglycerol) comprised the metabolic fuels of embryonic development. Following hatch (Day 16 post fertilisation), the fuels were free amino acids (32%), polar lipids (20%, mainly phosphatidyl choline), neutral lipids (17%, mainly triacylglycerol) and proteins (31%). Thus, the catabolic metabolism of endogenously feeding Atlantic cod larvae was predominantly fuelled by amino acids (67%) and lipids (32%), while glycogen only accounted for 1% of the total enthalpy dissipated. It is proposed that the above sequence of catabolic substrate oxidation is also generally applicable to other cold-water fishes which spawn eggs that do not contain oil glubules. 相似文献
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Tanja Schlaikjær Hartwig Louise Ambye Steen Sørensen Finn Stener Jørgensen 《黑龙江环境通报》2017,37(6):527-539
With a high sensitivity and specificity, non-invasive prenatal testing (NIPT) is an incomparable screening test for fetal aneuploidy. However, the method is rather newly introduced, and experiences with discordant results are few. We did a systematic review of literature reporting details of false positive and false negative NIPT results. Discordant sex chromosome results were not included. We identified 22 studies reporting case details. In total, 206 discordant cases were included, of which 88% were false positive and 12% false negative. Details on maternal age, gestational age, platform/company, Z-score, fetal fraction, results and explanation were specified. The main reasons for discordant results were confined placental mosaicism, maternal copy number variation, vanished twin, maternal cancer and true fetal mosaicism. A very high percentage of cases (67%) were reported with no obvious biological or technical explanation for the discordant result. The included cases represent only a minor part of the true number of false positive or false negative NIPT cases identified in fetal medicine clinics around the world. To ensure knowledge exchange and transparency of NIPT between laboratories, we suggest a systematic recording of discordant NIPT results, as well as a quality assurance by external quality control and accreditation. © 2017 John Wiley & Sons, Ltd. 相似文献
24.
Gordon Purvis Geertrui Louwagie Greg Northey Simon Mortimer Julian Park Alice Mauchline John Finn Jørgen Primdahl Henrik Vejre Jens Peter Vesterager Karlheinz Knickel Nadia Kasperczyk Katalin Balázs George Vlahos Stamatios Christopoulos Jukka Peltola 《Environmental Science & Policy》2009,12(3):321-337
An aggregated farm-level index, the Agri-environmental Footprint Index (AFI), based on multiple criteria methods and representing a harmonised approach to evaluation of EU agri-environmental schemes is described. The Index uses a common framework for the design and evaluation of policy that can be customised to locally relevant agri-environmental issues and circumstances. Evaluation can be strictly policy-focused, or broader and more holistic in that context-relevant assessment criteria that are not necessarily considered in the evaluated policy can nevertheless be incorporated. The Index structure is flexible, and can respond to diverse local needs. The process of Index construction is interactive, engaging farmers and other relevant stakeholders in a transparent decision-making process that can ensure acceptance of the outcome, help to forge an improved understanding of local agri-environmental priorities and potentially increase awareness of the critical role of farmers in environmental management. The structure of the AFI facilitates post-evaluation analysis of relative performance in different dimensions of the agri-environment, permitting identification of current strengths and weaknesses, and enabling future improvement in policy design. Quantification of the environmental impact of agriculture beyond the stated aims of policy using an ‘unweighted’ form of the AFI has potential as the basis of an ongoing system of environmental audit within a specified agricultural context. 相似文献
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One of the dual objectives of the Clean Development Mechanism (CDM) of the Kyoto Protocol is to assist host countries in achieving sustainable development. With various CDM indicators for 58 CDM host countries over the period 2005‐2010, this paper empirically assesses whether CDM project development fulfils its sustainable development objective. Using a unique dynamic panel data method based on the long‐differenced model, this research provides convincing evidence that CDM projects contribute to sustainable development in host countries. It sheds light on the role of the CDM in the process of global sustainability with clear policy implications for developing countries and those embracing market instruments. 相似文献
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Forest income and dependency in lowland Bolivia 总被引:1,自引:0,他引:1
Patricia Uberhuaga Carsten Smith-Hall Finn Helles 《Environment, Development and Sustainability》2012,14(1):3-23
Forests contribute to livelihoods of rural people throughout the tropics. This paper adds to the emerging body of quantitative
knowledge on absolute and relative economic importance, through both cash and subsistence income, of moist forests to households.
Qualitative contextual information was collected in six villages in lowland Bolivia, followed by a structured survey of randomly
selected households (n = 118) that included four quarterly income surveys. We employed a novel data collection approach that allows detailed estimation
of total household accounts, including sources of forest income. We estimated the average forest income share of total annual
household income (forest dependency) at 20%, ranging from 18 to 24%. Adding environmental income increased the average to
26%, being fairly constant across income quartiles at 24–28%. Absolute levels of forest income increased with total household
income, while forest dependency was the highest in the best-off income quartile—the primary harvesters of forest products
are better-off households. The pattern of high forest dependency among better-off households has also been reported from other
countries, indicating that this pattern may be more common than advocated by conventional wisdom. Using ordinary least squares
(OLS) regressions, we found significant determinants of absolute forest income to be household size, sex of household head
and area of cultivated land; the significant determinants for forest dependency were level of education, whether household
head was born in village and whether household was food self-sufficient. Better-off households were able to realise cash income
from forests, while poorer households—in particular if headed by women—were more reliant on subsistence forest income. We
argue that the differential patterns of forest income across income quartiles should be considered in future development interventions
and that findings indicate a potential for forests to contribute to moving households out of poverty. 相似文献
29.
Arun?Rijal Carsten?Smith-HallEmail author Finn?Helles 《Environment, Development and Sustainability》2011,13(1):121-140
Rural households throughout the Himalayas are regarded as dependent on non-timber forest products (NTFPs), but very few studies
have quantified this dependency. This case study, undertaken in two villages in the Central Himalayan foot hills in Nepal,
documents the absolute and relative importance of commercial NTFPs to rural household economies. Data were collected in a
one-year period and included interviews with 250 households using a semi-structured questionnaire and monthly interviews with
four sub-local NTFP traders, two local traders and two central wholesalers. The conservative estimate of NTFP-derived cash
income showed this to be a cornerstone in poorer household livelihood strategies and thus in poverty prevention. An annual
average of 578 kg of commercial NTFPs was collected in the wild per household, providing poorer households with a cash income
share of 44–78%. Better off households are not NTFP dependent but rely on income from crop production and livestock. Based
on a net marketing margin analysis, showing that harvesters capture a large share of the Indian wholesaler price, it is argued
that there is scope for pursuing NTFP-based strategies for poverty reduction through leasehold forestry and agroforestry.
Both these options are compatible with conserving forest cover and forest corridor functions and may thus present a win–win
scenario for livelihood improvement and conservation. 相似文献
30.
Channing Arndt Kenneth Strzepeck Finn Tarp James Thurlow Charles Fant IV Len Wright 《Sustainability Science》2011,6(1):7-20
Mozambique, like many African countries, is already highly susceptible to climate variability and extreme weather events. Climate change threatens to heighten this vulnerability. In order to evaluate potential impacts and adaptation options for Mozambique, we develop an integrated modeling framework that translates atmospheric changes from general circulation model projections into biophysical outcomes via detailed hydrologic, crop, hydropower and infrastructure models. These sector models simulate a historical baseline and four extreme climate change scenarios. Sector results are then passed down to a dynamic computable general equilibrium model, which is used to estimate economy-wide impacts on national welfare, as well as the total cost of damages caused by climate change. Potential damages without changes in policy are significant; our discounted estimates range from US$ 2.3 to US $7.4 billion during 2003?C2050. Our analysis identifies improved road design and agricultural sector investments as key ??no-regret?? adaptation measures, alongside intensified efforts to develop a more flexible and resilient society. Our findings also support the need for cooperative river basin management and the regional coordination of adaptation strategies. 相似文献