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1.
d fabrics increased with de 《印染助剂》2005,(6)
f 1.0%, and the chitosan having mol. wt. of 1 000 showed better antibacterial activity against gram-negative bacteria than gram-positive ones.chitosan; antibacterial activity; anti-crease property; finishing 相似文献
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The microbial community composition and dynamics during the production of a French soft, red-smear cheese were investigated. The colonization efficiency of the smearing inoculum was followed, and the parts played by the inoculum used and the resident microflora were tentatively estimated. Single-strand conformation polymorphism analysis (SSCP) was applied to 2 productions of a soft, red-smear cheese produced by the same dairy plant at 4-mo intervals. Microbial composition of the different cheese samples analyzed was found to be reproducible from one production to another. However, the composition of the surface flora of both cheeses at the end of the ripening did not reflect the composition of the smearing inoculum used, qualitatively as well as quantitatively. These results were confirmed by those obtained when assessing the microbial composition of the culturable flora by the spread plate technique. The inoculum used by the industry had low resiliency potentialities against colonization of cheeses by resident organisms. Therefore, fitness and colonization potential of smearing inocula should be carefully assessed by the industry before use. The use of Arthrobacter strains as part of the smearing inoculum should be evaluated. 相似文献
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《Food Hydrocolloids》1986,1(2):113-120
Influence of the concentration of sucrose and cellulose pulp on the compression behaviour of ϰ-carrageenan-based gels is studied. Composition of samples was established by using a second-order central composite design. Carrageenan concentrations used were between 0.5 and 1.25%, sucrose concentrations between 0 and 30% and cellulose fibre contents between 0 and 0.5%. Uniaxial compression behaviour was analysed by evaluating two parameters: maximum rupture strength (Fmax) and apparent Young's modulus (Eap). Results obtained showed that addition of sucrose increased both Fmax and Eap values while the effect of cellulose depended on the concentration of the other components. 相似文献
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Mário Vanoli Scatolino Camila Soares Fonseca Marcela da Silva Gomes Vinícius Dutra Rompa Maria Alice Martins Gustavo Henrique Denzin Tonoli Lourival Marin Mendes 《Holz als Roh- und Werkstoff》2018,76(6):1581-1594
The use of natural resources for the production of nanostructured cellulosic films of high quality could reduce pollution and raw material costs for cellulose industry. This work provides innovative information about the use of Amazonian species not explored in studies involving the production of nanostructured films, as well as the evaluation of important characteristics that may be decisive for the destination of the product. The aim of this study was to modify Schizolobium parahyba var. amazonicum (paricá) waste fibers through alkaline (NaOH) and bleaching (NaClO2) treatments for cellulose nanofibrils (CNFs) production and evaluate the characteristics of the nanofibrils and the surface as well as the mechanical resistance of the films obtained. The alkaline treatment was carried out with sodium hydroxide (5% NaOH solution (w/v); 2 h), while the bleaching was performed using sodium chlorite and glacial acetic acid (1.5 g NaClO2; 10 drops of glacial acetic acid; 1 h). The treatments were performed in sequence, producing nanofibrils after alkaline treatment and after bleaching. Lignin content did not change with the alkaline treatment, but it significantly decreased with bleaching (from 26.1 to 6.8%). Hemicelluloses content decreased with the sequence of treatments. FTIR results showed that the mechanical defibrillation caused disruption of the fiber bonds. The temperature of thermal degradation observed in DTG analysis increased from the natural fibers (243 °C) to alkaline?+?bleached fibers (255 °C). The defibrillation process led to higher thermal stability of the alkaline?+?bleached nanofibrils in comparison to fibers. Moreover, films were prepared from the obtained CNFs and evaluated by the mechanical properties and surface contact angle. The mechanical properties showed values of 6.93?±?0.18 GPa for modulus of elasticity (MOE) for the films produced from material which was submitted to the bleaching treatment. The results highlighted a more hydrophobic surface of the film produced with the CNFs generated from the bleached fibers. The results of mechanical properties showed the superiority of the films produced from the alkaline?+?bleached fibers. 相似文献
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A comprehensive food safety strategy requires the establishment of a farm-to-fork traceability system, which allows each step in the food chain to be followed and identified. This policy requires a multidisciplinary scientific approach including the wide … 相似文献
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ABSTRACT: Gelling temperatures of commercial κ-carrageenan solutions were measured using dynamic oscillatory shear rheometry, in response to varying polymer (0.4% to 1.6%, w/w) and added Ca2+ (5 to 20 mM) salts. Gelling temperatures were found to shift to higher temperatures with increased polymer and Ca2+ concentration. The Tang model was used to estimate the number of Ca2+-mediated cross-links formed with κ-carrageenan at the onset of junction zone formation. Based on this model, 6 κ-carrageenan double helices were estimated to be cross-linked by 5 Ca2+ ions through ionic bridging and electrostatic attraction, within a cross-linking region equivalent to one pitch of the double helix. 相似文献
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The available literature on tobacco endgames tends to be limited to discussing means, targets and difficulties. This article offers additional ideas on the key elements of endgame strategies and the circumstances in which these are likely to be adopted and implemented. We suggest such strategies will include explicit plans, will define the nature of `the end of tobacco use/sale' and have target dates within 20 years. The likely circumstances for endgame strategy development include low (probably under 15% adult smoking) prevalence and/or rapid prevalence reductions, wide support and strong political leadership. Even with some or all these circumstances, opposition from business, internal government forces and international factors may influence results. 相似文献
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《Food Hydrocolloids》1986,1(2):129-140
A range of galactomannans varying widely in the content of D-galactose have been compared for self-association, and their interaction properties with agarose and xanthan. The results presented indicate that in general the most interactive galactomannans are those in which the D-mannan main chain bears fewest D-galactose stubs, and confirm that the distribution of D-galactose groups along the main chain can have a significant effect on the interactive properties of the galactomannans. It has been shown that freeze — thaw precipitation of galactomannans requires regions of totally unsubstituted D-mannose residues along the main chain, and that a threshold for significant freeze — thaw precipitation occurs at a weight-average length of totally unsubstituted residues of approximately six. For galactomannans having structures above this threshold their interactive properties with other polysaccharides are controlled by structural features associated with totally unsubstituted regions of the D-mannan backbone. In contrast, for galactomannans below this threshold, their interactive properties are controlled by structural features associated with unsubstituted sides of D-mannan backbone. 相似文献
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The research of nutrition status of Primorsky Krai population in 1996-1999 showed positive tendency to quantitative improvement of structure of nutrition set. At the same time in connection a nutrition of Primorsky Krai population doesn't correspond to the standard of balanced nutrition. Some decrease of deficiency of basic food products in nutrition and an increase of energy value of food ration are observed. Children group of population is the most susceptible to unbalanced and defective nutrition that is why a pathology of digestive system of noninfectious nature develops intensively among children. 相似文献
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《家具与室内装饰》2007,(4)
The competition is open worldwide to architects, and designers as well as students enrolled in Tertiary Design Institutes and Fac- ulties of Architecture, who by 8th September 2007 have not reached the age of 40. The brief is the design of an INDOOR CHAIR, making significant use of wood. The 相似文献
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The germplasm of mutant mice is stored as frozen oocytes/embryos in many facilities worldwide. Their transport to and from such facilities should be easy and inexpensive with dry ice at -79?°C. The purpose of our study was to determine the stability of mouse oocytes with time at that temperature. The metaphase II oocytes were cryopreserved with a vitrification solution (EAFS10/10) developed by M Kasai and colleagues. Two procedures were followed. In one, the samples were cooled at 187?°C/min to -196?°C, warmed to -80?°C, held at -80?°C for 1 h to 3 months, and warmed to 25?°C at one of three rates. With the highest warming rate (2950?°C/min), survival remained at 75% for the first month, but then slowly declined to 40% over the next 2 months. With the slowest warming (139?°C/min), survival was only ~ 5% even at 0 time at -80?°C. In the second procedure, the samples were cooled at 294?°C/min to -80?°C (without cooling to -196?°C) and held for up to 3 months before warming at 2950?°C/min. Survival was ~ 90% after 7 days and dropped slowly to 35% after 3 months. We believe that small non-lethal quantities of intracellular ice formed during the cooling and that the intracellular crystals increased to a damaging size by recrystallization during the 3 month's storage at -80?°C. From the practical point of view, this protocol yields sufficient stability to make it feasible to ship oocytes worldwide in dry ice. 相似文献
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The present study evaluated the effects of three galactomannans on the physical and nutritional characteristics, and sensory acceptability of pea–rice based extruded products, targeted as nutritional snacks. A base blend of 70:30 pea and rice fortified with guar gum (GG), locust bean gum (LBG) and fenugreek gum (FG), at 5%, 10%, 15% and 20%, was extruded at pre-determined optimum processing conditions. All three gums resulted in good expanded products. Increasing the inclusion levels of gums, however, had no effect (P > 0.05) on the degree of expansion. Addition of 5% GG and LBG reduced (P < 0.05) the hardness, while the inclusion of GG and LBG at levels higher than 5%, and all inclusion levels of FG, increased (P < 0.05) the hardness of extruded products. Relative to other treatments, FG produced extrudates that were harder and crispier. The mean scores of sensory evaluation indicated that all products containing gums up to 15% were within the acceptable range. Extrusion increased (P < 0.001) the soluble fibre content and decreased the insoluble fraction; the magnitude of these changes were greater in GG and FG. The addition of 15% gums in the pea–rice blend reduced (P < 0.05) the glycaemic index to less than 55. Overall, the data suggest that all three galactomannans could be incorporated up to 15% in a pea–rice blend to develop nutritious, organoleptically acceptable, extruded snack products with low glycaemic index. 相似文献
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The beard method is used for sampling cotton fibers to generate fibrograms from which length parameters can be obtained. It is the sampling method used by the Uster High Volume Instrument (HVI?). A fundamental issue of this sampling method is its bias since the mathematical computation to obtain length parameters is quite different. There have been different assumptions regarding the bias of the beard sampling method. In our experiments, we have seen discrepancies in measurements that cannot be explained as length‐biased or unbiased, especially in the short fiber region. We report a fundamental research, including experimental and theoretical analysis, and computer simulations, that reveals the bias due to this sampling method. We find that the beard sampling method as used in HVI is not completely length‐biased; fibers sampled by using this method are similar to the original fibers except in the short fiber region. Short fiber content (SFC) of the sampled fiber is lower than that of the original fiber, and this difference is inherently introduced by the sampling method. 相似文献
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the oceanic for up 《食品科技》2004,(4)
fers the atmospheric CO 2 into dissolved carbonate species in surface seawaters through physiochemical processes, the “biological pump”, which fixes CO 2 in organism's tissues through photosynthesis and processes in two deep carbon reservoirs—the deep sea and sediments, were discussed. The “buffering effects” in the ocean on increased anthropogenic CO 2 and the current methodolo 相似文献
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Murat Ozalp 《Holz als Roh- und Werkstoff》2011,69(3):369-374
In the present study, the effect of adding the powder of waste PET (polyethylene terephthalate) bottles and borax pentahydrate in equal amounts to the urea-formaldehyde (UF) adhesive on the bonding characteristics and free formaldehyde content was studied. Experiments were conducted on three layered plywood of beech (Fagus orientalis) and poplar (Populus x eureamericana), which were produced using urea-formaldehyde adhesive to which powdered PET bottle and borax pentahydrate were added in certain amounts. Furthermore, the bending strength of the produced plywood was analyzed according to BS EN 320, the withdrawal shear strength according to BS EN 314-2, and the free formaldehyde content according to EN 717-2. The obtained results were then compared. It can be seen that the addition of powdered PET bottle and borax pentahydrate to the adhesive mixture used on the plywood statistically increased its bending strength and withdrawal shear strength but significantly reduced the free formaldehyde content. 相似文献