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41.
Evaluating the Potential for Harmonized Prediction and Comparison of Disposal‐Stage Greenhouse Gas Emissions for Biomaterial Products 下载免费PDF全文
David Glew Lindsay C. Stringer Adolf Acquaye Simon McQueen‐Mason 《Journal of Industrial Ecology》2017,21(1):101-115
The carbon footprint (CF) of biofuels and biomaterials is a barrier to their acceptance, yet the greenhouse gas emissions associated with disposing of biomaterials are frequently omitted from analyses. This article investigates whether harmonization is appropriate for calculating the importance of biomaterials’ disposal. This research shows that disposal stages could double a biomaterial's CF, or reduce it to the point that it could claim to be zero carbon. Incineration with combined heat and power coupled with on‐site energy production in the biorefinery are identified as prerequisites to being zero carbon. The article assesses the current UK waste infrastructure's ability to support a low‐carbon bio‐based future economy, and finds that presently it only achieves marginal net reductions when compared to landfill and so cannot be said to support low‐carbon biomaterials, though the article challenges the polluter pays principle where low‐carbon disposal infrastructure are not available. Reuse and recycling are shown to have the potential to offset all the emissions caused by landfill of biomaterials. However, the savings are not so great as to offset the biomaterial's upstream emissions. The study explores the ability to overcome the barriers to incorporating disposal into life cycle assessment while identifying limitations of using harmonization as an assessment method. Specifically, data availability and industry consensus are flagged as major barriers. The study also uses sensitivity analysis to investigate the influence of methodological choices, such as allowing additional reuse and recycling stages, classifying biomaterials into different types, and choosing between opposing allocation methods. 相似文献
42.
Butterweck V Christoffel V Nahrstedt A Petereit F Spengler B Winterhoff H 《Life sciences》2003,73(5):627-639
Herbal extracts of Hypericum perforatum L. (St. John's wort, SJW) are now successfully competing for status as a standard antidepressant therapy. Because of this, great effort has been devoted to identifying the antidepressive active compounds. In the present study we used the following strategy to evaluate the relative pharmacological importance of various extract components: 1. preparation of an hydroalcoholic SJW extract containing both hyperforin (3.2%) and hypericin (0.15%) (extract A); 2. step by step removal of hyperforin and hypericin led to the following extracts: Extract B, devoid of hyperforin but still containing hypericin (0.14%) and Extract C, free of hypericin and hyperforin but enriched in flavonoids ( approximately 12%). We characterized the in vivo activity profile of all three preparations using the tail suspension test (TST) in mice and the forced swimming test (FST) in rats as screening models. We further investigated the activity of pure hyperforin. Extract B and C (500 mg/kg each) as well as pure hyperforin (8 mg/kg) significantly shortened immobility time in the TST after acute pre-treatment whereas extract A was inactive. In the FST all three extracts decreased immobility time in a dosage of 500 mg/kg after acute as well as after repeated treatment. The present results clearly show that an SJW extract free of hyperforin and hypericin exerts antidepressant activity in behavioral models, supporting our working hypothesis that flavonoids are part of the constituents responsible for the therapeutic efficacy of SJW extracts. We also could show that hyperforin contributes to the beneficial properties of SJW extract, confirming the hypothesis that the crude SJW extract contains several constituents with antidepressant activity. 相似文献
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44.
Global surface temperature has been increasing since the beginning of the 20th century but with a highly variable warming rate, and the alternation of rapid warming periods with ‘hiatus’ decades is a constant throughout the series. The superimposition of a secular warming trend with natural multidecadal variability is the most accepted explanation for such a pattern. Since the start of the 21st century, the surface global mean temperature has not risen at the same rate as the top-of-atmosphere radiative energy input or greenhouse gas emissions, provoking scientific and social interest in determining the causes of this apparent discrepancy. Multidecadal natural variability is the most commonly proposed cause for the present hiatus period. Here, we analyze the HadCRUT4 surface temperature database with spectral techniques to separate a multidecadal oscillation (MDV) from a secular trend (ST). Both signals combined account for nearly 88% of the total variability of the temperature series showing the main acceleration/deceleration periods already described elsewhere. Three stalling periods with very little warming could be found within the series, from 1878 to 1907, from 1945 to 1969 and from 2001 to the end of the series, all of them coincided with a cooling phase of the MDV. Henceforth, MDV seems to be the main cause of the different hiatus periods shown by the global surface temperature records. However, and contrary to the two previous events, during the current hiatus period, the ST shows a strong fluctuation on the warming rate, with a large acceleration (0.0085°C year−1 to 0.017°C year−1) during 1992–2001 and a sharp deceleration (0.017°C year−1 to 0.003°C year−1) from 2002 onwards. This is the first time in the observational record that the ST shows such variability, so determining the causes and consequences of this change of behavior needs to be addressed by the scientific community. 相似文献
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The three major curcuminoids, curcumin, demethoxycurcumin and bis-demethoxycurcumin, from Curcuma domestica Val. (Curcuma longa L.) and Curcuma xanthorrhiza Roxb. (Zingiberaceae) were fully separated and quantified in less than 5 min using a capillary zone electrophoresis method with standard fused-silica capillaries and photodiode array detection. An electrolyte solution of 20 mM phosphate, 50 mM sodium hydroxide and 14 mM beta-cyclodextrin was found to be appropriate. Quantification was performed with 3,4-dimethoxy-trans-cinnamic acid as internal standard, and the limit of detection was 0.01 mg/mL. Extraction, stabilisation during sample storage and quantification procedures were optimised and carried out with drugs and commercial curry powder from different provenances. The results were compared with the photometric method of the monograph Curcumae xanthorrhizae rhizoma of the European Pharmacopoeia. 相似文献
47.
Dr. Adolf Herfs 《Zoomorphology》1963,53(1):29-38
Ohne Zusammenfassung 相似文献
48.
Adolf Kotthaus 《Helgoland Marine Research》1939,1(3):349-358
Ohne ZusammenfassungMit 4 Abbildungen im Text.Anm. Die Arbeit wurde durch eine Beihilfe der deutschen Forschungsgemeinschaft ermöglicht. 相似文献
49.
Adolf Kappus 《Molecular & general genetics : MGG》1957,88(1):38-55
Ohne ZusammenfassungMit 3 TextabbildungenGekürzte Fassung einer Dissertation. 相似文献
50.