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61.
加工技术与设备的发展通常会使加工时间缩短.但是新型助剂的应用也可减少加工时间,大大降低成本.随着iFlash系统的应用,漂白温度可降至80℃,活性染料染色后皂洗的时间也大大缩短.因此,织物间歇式染色得到优化,在不增加额外投资的情况下运行更经济. 相似文献
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Herbert Stutz 《应用聚合物科学杂志》2004,91(3):1881-1886
The kinetics of thermal degradation of 4,4′‐diaminodiphenylsulfone (DDS)‐cured glycidylethers (DGBA) and glycidylamines (TGDDM) have been studied by isothermal annealing. Thermal degradation proceeds via first‐order kinetics with activation energies of 138 (DGBA/DDS) and 95 kJ/mol (TGDDM/DDS). From these data the temperature‐dependent lifetime can be calculated. Based on the heat distortion temperature and 20 years' service as criteria, the upper service temperature is found to be around 115–120°C. In spite of the different activation energies and bond stabilities, only marginal differences in the upper allowed service temperatures between these resins were found. Only slight improvements can be expected by optimizing the cure conditions. © 2003 Wiley Periodicals, Inc. J Appl Polym Sci 91: 1881–1886, 2004 相似文献
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Khanderi J Contiu C Engstler J Hoffmann RC Schneider JJ Drochner A Vogel H 《Nanoscale》2011,3(3):1102-1112
Cuprous oxide agglomerates composed of 4-10 nm Cu2O nanoparticles were deposited on multiwalled carbon nanotubes (MWCNTs) and on ZnO/MWCNTs to give binary [Cu2O/MWCNT] and ternary [Cu2O/ZnO/MWCNT] composites. Di-aqua-bis[2-(methoxyimino)propanoato]copper Cu[O2CCCH3NOMe](2)·2H2O 1 in DMF was used as single source precursor for the deposition of nanoscaled Cu2O. The precursor decomposes either in air or under argon to yield CuO2 by in situ redox reaction. Thermogravimetric coupled mass spectroscopic analysis (TG-MS) of 1 revealed that methanol formed during the decomposition of 1 acts as a potential in situ reducing agent. Scanning electron microscopy (SEM) of the binary [Cu2O/MWCNT] nano-composite shows an increase of cuprous oxide loading depending on the precursor amount, along the periphery of the MWCNTs as well as formation of larger particle agglomerates. Transmission electron microscopy (TEM) of the sample shows crystalline domains of size 4-10 nm surrounded by an amorphous region within the larger particles. SEM and TEM of ternary [Cu2O/ZnO/MWCNT] clearly reveal that Cu2O nanoparticles are primarily deposited on ZnO rather than on MWCNTs. The catalytic activities of the [Cu2O/MWCNT] and [Cu2O/ZnO/MWCNT] binary and ternary composites were studied for the selective partial oxidation of ethanol to acetaldehyde with molecular oxygen. While using binary [Cu2O/MWCNT] (13.8 wt% Cu) as catalyst, acetaldehyde was obtained with a yield of 87% at 355 °C (selectivity 96% and conversion 91%). When nanoscale ZnO is present, the resulting [Cu2O/ZnO/MWCNT] composite shows preferential hydrogen and CO2 formation due to the fact that the dehydrogenation and total oxidation pathway is more favoured compared to the binary composite. Significant morphological changes of the catalyst during the catalytic process were observed. 相似文献
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Optimizing a heat pump driven forced-air domestic heating system utilizing solar/thermal energy storage and off-peak storage from the electric power network is discussed. The system proposed is modeled and simulated on the digital computer. An optimal controller is then developed to maximize comfort and minimize conventional energy consumption. The controller is then simulated with the heating system for the University of Toledo experimental electric/solar house, Toledo, OH, and shown to be truly optimal and able to control the system in a desirable manner. 相似文献
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The phagostimulatory sensitivity of diabroticite (Coleoptera, Chrysomelidae, Galerucinae) species to cucurbitacins is not correlated with Cucurbitaceae specialization, indicating that other factors, including the absence of feeding deterrents, may influence host–plant affinities among these beetles. Quinoline, indole, and isoquinoline alkaloids and sesquiterpene lactones believed to antagonize γ-aminobutyric acid/glycine Cl? ionophores mediating chemoreception were tested on squash blossom disks for antifeedant activity to four diabroticite species with different host plant specializations. Most alkaloids were antifeedant below 30 nmol/disk. Antifeedant concentrations of sesquiterpene lactones were higher than alkaloids for all species. Oligophagous Diabrotica virgifera virgifera was more sensitive to quinoline alkaloids than polyphagous D. undecimpuntata howardi. Diabrotica virgifera virgifera was also more sensitive to the indole alkaloids strychnine, brucine, eburnamonine, and vincamine than D. u. howardi. The closely related D. barberi had sensitivities similar to those of D. v. virgifera but the more distantly related Acalymma vittatum was less sensitive to the antifeedants than D. v. virgifera The isoquinoline alkaloid hydrastine was uniformly antifeedant to all diabroticites. All the GABA/glycine neurotoxicams tested against diabroticites were feeding deterrents and suggest that beetles share a common antifeedant mechanism. 相似文献
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Specificity of Lipoprotein Chaperones for the Characteristic Lipidated Structural Motifs of their Cognate Lipoproteins
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Dr. Tom Mejuch Dr. Hilde van Hattum Dr. Gemma Triola Dr. Mamta Jaiswal Prof. Dr. Herbert Waldmann 《Chembiochem : a European journal of chemical biology》2015,16(17):2460-2465
Lipoprotein‐binding chaperones mediate intracellular transport of lipidated proteins and determine their proper localisation and functioning. Understanding of the exact structural parameters that determine recognition and transport by different chaperones is of major interest. We have synthesised several lipid‐modified peptides, representative of different lipoprotein classes, and have investigated their binding to the relevant chaperones PDEδ, UNC119a, UNC119b, and galectins‐1 and ‐3. Our results demonstrate that PDEδ recognises S‐isoprenylated C‐terminal peptidic structures but not N‐myristoylated peptides. In contrast, UNC119 proteins bind only mono‐N‐myristoylated, but do not recognise doubly lipidated and S‐isoprenylated peptides at the C terminus. For galectins‐1 and ‐3, neither binding to N‐acylated, nor to C‐terminally prenylated peptides could be determined. These results shed light on the specificity of the chaperone‐mediated cellular lipoprotein transport systems. 相似文献
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