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51.

Purpose

India’s biofuel programme relies on ethanol production from sugarcane molasses. However, there is limited insight on environmental impacts across the Indian ethanol production chain. This study closes this gap by assessing the environmental impacts of ethanol production from sugarcane molasses in Uttar Pradesh, India. A comparative analysis with south-central Brazilian sugarcane ethanol is also presented to compare the performance of sugarcane molasses-based ethanol with sugarcane juice-based ethanol.

Methods

The production process is assessed by a cradle-to-gate life cycle assessment. The multifunctionality problem is solved by applying two variants of system expansion and economic allocation. Environmental impacts are assessed with Impact 2002+ and results are presented at the midpoint level for greenhouse gas emissions, non-renewable energy use, freshwater eutrophication and water use. Furthermore, results include impacts on human health and ecosystem quality at the damage level. Sensitivity analysis is also performed on key contributing parameters such as pesticides, stillage treatment and irrigation water use.

Results and discussion

It is found that, compared to Brazilian ethanol, Indian ethanol causes lower or comparable greenhouse gas emissions (0.09–0.64 kgCO2eq/kgethanolIN, 0.46–0.63 kgCO2eq/kgethanolBR), non-renewable energy use (?0.3–6.3 MJ/kgethanolIN, 1–4 MJ/kgethanolBR), human health impacts (3.6?·?10?6 DALY/kgethanolIN, 4?·?10?6 DALY/kgethanolBR) and ecosystem impairment (2.5 PDF?·?m2?·?year/kgethanolIN, 3.3 PDF?·?m2?·?year/kgethanolBR). One reason is that Indian ethanol is exclusively produced from molasses, a co-product of sugar production, resulting in allocation of the environmental burden. Additionally, Indian sugar mills and distilleries produce surplus electricity for which they receive credits for displacing grid electricity of relatively high CO2 emission intensity. When economic allocation is applied, the greenhouse gas emissions for Indian and Brazilian ethanol are comparable. Non-renewable energy use is higher for Indian ethanol, primarily due to energy requirements for irrigation. For water use and related impacts, Indian ethanol scores worse due groundwater irrigation, despite the dampening effect of allocation. The variation on greenhouse gas emissions and non-renewable energy use of Indian mills is much larger for high and low performance than the respective systems in Brazil.

Conclusions

Important measures can be taken across the production chain to improve the environmental performance of Indian ethanol production (e.g. avoiding the use of specific pesticides, avoiding the disposal of untreated stillage, transition to water efficient crops). However, to meet the targets of the Indian ethanol blending programme, displacement effects are likely to occur in countries which export ethanol. To assess such effects, a consequential study needs to be prepared.  相似文献   
52.

Purpose

The aim of the paper is to assess the role and effectiveness of a proposed novel strategy for Life Cycle Inventory (LCI) data collection in the food sector and associated supply chains. The study represents one of the first of its type and provides answers to some of the key questions regarding the data collection process developed, managed and implemented by a multinational food company across the supply chain.

Methods

An integrated LCI data collection process for confectionery products was developed and implemented by Nestlé, a multinational food company. Some of the key features includes (1) management and implementation by a multinational food company; (2) types of roles to manage, provide and facilitate data exchange; (3) procedures to identify key products, suppliers and customers; (4) LCI questionnaire and cover letter and (5) data quality management based on the pedigree matrix. Overall, the combined features in an integrated framework provide a new way of thinking about the collection of LCI data from the perspective of a multinational food company.

Results and discussion

The integrated LCI collection framework spanned across 5 months and resulted in 87 new LCI datasets for confectionery products from raw material, primary resource use, emission and waste release data collected from suppliers across 19 countries. The data collected was found to be of medium to high quality compared with secondary data. However, for retailers and waste service companies, only partially completed questionnaires were returned. Some of the key challenges encountered during the collection and creation of data included lack of experience, identifying key actors, communication and technical language, commercial compromise, confidentiality protection and complexity of multi-tiered supplier systems. A range of recommendations are proposed to reconcile these challenges which include standardisation of environmental data from suppliers, concise and targeted LCI questionnaires and visualising complexity through drawings.

Conclusions

The integrated LCI data collection process and strategy has demonstrated the potential role of a multinational company to quickly engage and act as a strong enabler to unlock latent data for various aspects of the confectionery supply chain. Overall, it is recommended that the research findings serve as the foundations to transition towards a standardised procedure which can practically guide other multinational companies to considerably increase the availability of LCI data.
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Our studies in rats clearly demonstrate a significant depression of aminopyrine metabolism in vivo by ether anesthesia. The depression of aminopyrine elimination was shown both by measurements of plasma aminopyrine clearance and by depression of the [14C]aminopyrine breath test. No apparent effect of ether was seen on aminopyrine volume of distribution. The effect of ether was prolonged, as judged by its persistence in the aminopyrine breath test for 3 hr after stopping ether anesthesia. In addition, when ether was administered in combination with a single dose of ethanol, aminopyrine clearance was inhibited significantly more than with ethanol alone. These data not only have a bearing on proper methodologic design of drug clearance studies but also may relate to the effects of some anesthetics on hepatic function.  相似文献   
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The kinetics of phosphocreatine (PC) breakdown in human plantar flexors at the onset of constant-load aerobic exercise was determined by high-resolution 31P-nuclear magnetic resonance spectroscopy (NMRS). The half time of the process (t1/2PC) was obtained by fitting curves (n = 13) from five subjects at various aerobic work loads for which muscle pH was not different from that at rest. Steady-state PC concentration ([PC]) was not < 70% of the resting value and was linearly related to the work load (w) ([PC] = -3.01 +/- 0.08 w + 1 (r = 0.48, 2P < 0.1)). The average t1/2PC was 16.2 s and was independent of work load. Because the half time of the muscle PC kinetics reflects the half time of the O2 uptake (MO2) kinetics (t1/2MO2), the latter is equal to that found earlier in the isolated perfused dog gastrocnemius. Whereas in the dog the above t1/2MO2 compares well with the homologous half time of the O2 uptake at the alveolar level, in humans such equivalence is found only at extremely low work loads, when the transient contribution by anaerobic glycolysis is negligible.  相似文献   
59.
Summary Some twenty cases of dispermic chimeras with the karyotype 46,XX/46,XY, discovered because of gonadal dysplasias or a true hermaphroditism, have been reported. This is a report of a phenotypically normal man with 46,XX/46,XY chimerism in whom a prepubertal finding of positive X-chromatin was interpreted as Klinefelter syndrome. The diagnosis was revised 11 years later when the family doctor, who doubted the earlier diagnosis because of the patient's normal-sized testes, sent him to an outpatient clinic. The young man was 23 years old, athletic (74kg, 180cm), with normal body proportions, normal sexual hair distribution, normal libido and potency, normal endocrine parameters, and a normal spermiogram. The karyotype revealed an XX/XY mosaic in a proportion of 1:2. An identical set of maternal markers (Q- and C-banding) was present in male and female cells. Differences were found with respect to two paternal markers. Furthermore, blood, serum, and red cell enzyme groups in five systems showed two phenotypes, again with duality of paternal origin. It is concluded that a positive X-chromatin in prepuperty, especially in the absence of supporting clinical features, must be followed by a karyotype study.  相似文献   
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Editorial note     
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