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71.
Recent developments in the formulation of detergents have been driven by a strong consumer demand for natural and biodegradable products. Detergent manufacturers responded to this demand with corresponding products and advertising slogans such as “fully biodegradable”, “natural” or even “double natural” to oust their competitors. In a detergent formulation, starch- derived products can in principle be used for the following purposes: as the hydrophilic head group in surfactants, as the starting material for (poly)carboxylate co-builders and as the backbone of bleaching activators. Non-ionic classical surfactants can be replaced by alkylpolyglucosides (APGs), a class of products completely based on renewable resources such as glucose and fatty alcohols derived from natural fatty acids. Sodium tripolyphosphate (STPP), the product responsible for the eutrophication of surface waters, can be substituted by a combination of an inorganic zeolite and highly oxidised starch (dicarboxylic starch) or by citrate. Acetylated polyols derived from hydrogenated carbohydrates such as sorbitol can take over the function of the petrochemically-based tetraacetyl ethylene diamine (TAED) used as activator to allow perborate bleaching at lower washing temperatures. 相似文献
72.
73.
Weakly lignified biomass, like brewers' spent grain and grass silage, is good feedstock for biorefineries. The biomass can be separated and converted into valuable products in different ways. In this study, brewers' spent grain is used to investigate solid state fermentations with Cellulomonas uda. Additionally, hydrothermal pretreatment and subsequent enzymatic saccharification, as well as formation of inhibitory compounds, is demonstrated. Hydrothermal pretreatment combined with simultaneous saccharification and fermentation is shown as an example for the utilization of grass silage. 相似文献
74.
Amalia Ruiz-Serrano Christina N. Boyle Josep M. Monn Rodríguez Julia Günter Agnieszka E. Jucht Svende Pfundstein Andreas M. Bapst Thomas A. Lutz Roland H. Wenger Carsten C. Scholz 《International journal of molecular sciences》2022,23(3)
Dysregulated energy metabolism is a major contributor to a multitude of pathologies, including obesity and diabetes. Understanding the regulation of metabolic homeostasis is of utmost importance for the identification of therapeutic targets for the treatment of metabolically driven diseases. We previously identified the deubiquitinase OTUB1 as substrate for the cellular oxygen sensor factor-inhibiting HIF (FIH) with regulatory effects on cellular energy metabolism, but the physiological relevance of OTUB1 is unclear. Here, we report that the induced global deletion of OTUB1 in adult mice (Otub1 iKO) elevated energy expenditure, reduced age-dependent body weight gain, facilitated blood glucose clearance and lowered basal plasma insulin levels. The respiratory exchange ratio was maintained, indicating an unaltered nutrient oxidation. In addition, Otub1 deletion in cells enhanced AKT activity, leading to a larger cell size, higher ATP levels and reduced AMPK phosphorylation. AKT is an integral part of insulin-mediated signaling and Otub1 iKO mice presented with increased AKT phosphorylation following acute insulin administration combined with insulin hypersensitivity. We conclude that OTUB1 is an important regulator of metabolic homeostasis. 相似文献
75.
76.
The objective of this study was to evaluate the suitability of the V-Sight hematology analyzer (A. Menarini Pharma GmbH, Vienna, Austria) for bovine blood by a comparison with a reference device (Advia 2120i, Siemens AG, Erlangen, Germany). In total, 97 blood samples were obtained from 75 dairy cows. Analyzed parameters included counts of white blood cells (WBC), lymphocytes, monocytes, granulocytes, red blood cells (RBC), and platelets (PLT), as well as hemoglobin concentration (HGB), hematocrit (HCT), mean corpuscular volume, mean corpuscular hemoglobin (MCH), MCH concentration (MCHC), mean platelet volume (MPV), and plateletcrit (PCT). Based on Passing-Bablok regression, the V-Sight provided accurate and precise results for MCH and MCHC only. The PCT results were comparable to the reference method, but precision was inconclusive. Significant proportional differences were detected for monocytes, granulocytes, HCT, and PLT. For all other analytes, significant proportional and systemic differences were observed. The WBC and lymphocyte results from the V-Sight were characterized by poor accuracy, poor precision, and a high number of false positive outliers. Bland-Altman analysis indicated negative biases for all WBC parameters, the erythrocyte indices, and PLT. Positive biases were observed for RBC, HGB, HCT, MPV, and PCT. Correlation coefficients of >0.9 between the V-Sight and the reference method were found only for RBC, HGB, HCT, and MPV. Intraassay precision of the V-Sight analyzer was acceptable (coefficient of variation <5%) for granulocytes, the erythrocyte indices, and MPV. It was unacceptable (coefficient of variation ≥5%) for WBC, lymphocytes, monocytes, as well as RBC, and inconclusive for HGB, HCT, PLT, and PCT. Sensitivity was high for all RBC counts and indices as well as PLT, but low for monocytes, granulocytes, and MPV. Specificity was high for monocytes and granulocytes, but low for RBC, HCT, MCH, and MCHC. With accurate and precise results for only 2 out of 13 parameters, the V-Sight cannot be recommended for analysis of bovine blood. 相似文献
77.
Ulrich Müller Martine Philipp Jan Christoph Gaukler Wulff Possart Roland Sanctuary Jan Kristian Krüger 《The Journal of Adhesion》2013,89(3):253-276
The curing of an epoxy consisting of the solid hardener dicyandiamide (DICY) and the resin diglycidyl ether of bisphenol A (DGEBA) is studied in a system consisting of a tablet of DICY embedded in liquid DGEBA. Dissolution of DICY within the liquid DGEBA in combination with the transport of dissolved DICY from the tablet border into DGEBA and the chemical reaction of both reactants is studied by scanning Brillouin microscopy and infrared spectroscopy. Scanning Brillouin microscopy demonstrates the spatial and temporal evolution of the static and dynamic hypersonic properties in the course of curing in the vicinity of the DICY tablet. Infrared spectroscopy performed on epoxy pieces extracted from the final sample at different distances from the tablet surface give information about the spatial evolution of the curing process. The results achieved by both techniques are finally combined to yield a better understanding of the curing of DICY-based epoxies, which transform upon curing from strongly heterogeneous systems towards increasingly homogeneous systems. 相似文献
78.
79.
Soil organic carbon changes in the cultivation of energy crops: Implications for GHG balances and soil quality for use in LCA 总被引:1,自引:0,他引:1
The environmental impact of different land-use systems for energy, up to the farm or forest “gate”, has been quantified with Life Cycle Assessment (LCA). Four representative crops are considered: OilSeed Rape (OSR), Miscanthus, Short-Rotation Coppice (SRC) willow and forest residues. The focus of the LCA is on changes in Soil Organic Carbon (SOC) but energy use, emissions of GreenHouse Gases (GHGs), acidification and eutrophication are also considered. In addition to providing an indicator of soil quality, changes in SOC are shown to have a dominant effect on total GHG emissions. Miscanthus is the best land-use option for GHG emissions and soil quality as it sequesters C at a higher rate than the other crops, but this has to be weighed against other environmental impacts where Miscanthus performs worse, such as acidification and eutrophication. OSR shows the worst performance across all categories. Because forest residues are treated as a by-product, their environmental impacts are small in all categories. The analysis highlights the need for detailed site-specific modelling of SOC changes, and for consequential LCAs of the whole fuel cycle including transport and use. 相似文献
80.
This study presents a planning model for Swedish activities in the field of wind power. Models and results of calculations of the land-based wind energy potential with the Wind Atlas Analysis and Application Programme, WAsP, are described and analysed in a geographical information systems (GIS) called the ArcView® GIS system. One county in southern Sweden was chosen as a case study to present the methods used. The results from that case study indicate a great wind energy potential but there are nevertheless many factors limiting that potential. The study calls for a further development of planning tools in the field. Important areas for the future are the development of knowledge in market issues, wind power technology, environmental issues, and public opinion on constructing wind turbines. 相似文献