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排序方式: 共有1696条查询结果,搜索用时 62 毫秒
91.
用于非织造材料的Tencel Lyocell纤维 总被引:1,自引:0,他引:1
Lenzing纤维公司开发的Lyocell纤维构成了一个纤维产品系列,用于要求具有吸湿性、纯度、柔软性、强度和生物降解性的各种各样非织造产品.述评了长度短的短纤维(低于20 mm)的特性和制得的织物的性质,重点是如何能利用上述纤维设计高性能非织造材料的重要产品性质. 相似文献
92.
93.
Liang Li Anders Rasmuson Andy Ingram Mats Johansson Johan Remmelgas Christian von Corswant Staffan Folestad 《American Institute of Chemical Engineers》2015,61(3):756-768
Particle cycle and residence time distributions are critical factors in determining the coating quality in the Wurster process. Positron emission particle tracking experiments are performed to determine the cycle and residence times of particles in different regions of a Wurster fluid bed. The results show that particles tend to recirculate in and sneak out below from the Wurster tube. The experiments also show that a larger batch size leads to a shorter cycle time and a narrower cycle time distribution (CTD). It is possible to avoid recirculations and obtain a shorter cycle time and a narrower CTD by selecting the operating conditions appropriately or via equipment design. Experiments using binary mixtures of particles with a diameter ratio of 1.5 show that large particles have a longer cycle time than small particles and that the cycle time is shorter for mixtures with approximately equal amounts of small and large particles. © 2014 American Institute of Chemical Engineers AIChE J, 61: 756–768, 2015 相似文献
94.
W. Liou 《Journal of microscopy》1990,157(2):239-245
A technique is given for the preparation of a sheet of epithelial cells from the capsule of the crystalline lens. A new method is described for fixation and staining with fluorescent phalloidin or actin antibody in order to localize the actin cytoskeleton in this tissue. Optical section of the preparation resolves such actin features as apical polygonal arrays, sequestered actin bundles, perinuclear actin aggregates, observed here for the first time, and filamentous networks in the basal region of the cell. This method is superior to previous ones in its ability to preserve actin-abundant sectors distinctively. 相似文献
95.
Andrews MJ Kontopidis G McInnes C Plater A Innes L Cowan A Jewsbury P Fischer PM 《Chembiochem : a European journal of chemical biology》2006,7(12):1909-1915
We describe a drug-design strategy termed REPLACE (REplacement with Partial Ligand Alternatives through Computational Enrichment) in which nonpeptidic surrogates for specific determinants of known peptide ligands are identified in silico by using a core peptide-bound protein structure as a design anchor. In the REPLACE application example, we present the effective replacement of two critical binding motifs in a lead protein-protein interaction inhibitor pentapeptide with more druglike phenyltriazole and diphenyl ether groups. These were identified through docking of fragment libraries into the volume of the cyclin-binding groove of CDK2/cyclin A vacated through truncation of the inhibitor peptide-binding determinants. Proof of concept for this strategy was obtained through the generation of potent peptide-small-molecule hybrids and by the confirmation of inhibitor-binding modes in X-ray crystal structures. This method therefore allows nonpeptide fragments to be identified without the requirement for a high-sensitivity binding assay and should be generally applicable in replacing amino acids as individual residues or groups in peptide inhibitors to generate pharmaceutically acceptable lead molecules. 相似文献
96.
Jing L Zhang J Sun J Guo F An X Yang K Li PA 《International journal of molecular sciences》2011,12(12):8333-8346
The aim of this study is to investigate the effect of the extracellular signal-regulated kinases 1/2 (ERK1/2) inhibitor, PD98059, on high blood pressure and related vascular changes. Blood pressure was recorded, thicknesses of renal small artery walls were measured and ERK1/2 immunoreactivity and erk2 mRNA in renal vascular smooth muscle cells (VSMCs) and endothelial cells were detected by immunohistochemistry and in situ hybridization in normotensive wistar kyoto (WKY) rats, spontaneously hypertensive rats (SHR) and PD98059-treated SHR. Compared with normo-tensive WKY rats, SHR developed hypertension at 8 weeks of age, thickened renal small artery wall and asymmetric arrangement of VSMCs at 16 and 24 weeks of age. Phospho-ERK1/2 immunoreactivity and erk2 mRNA expression levels were increased in VSMCs and endothelial cells of the renal small arteries in the SHR. Treating SHR with PD98059 reduced the spontaneous hypertension-induced vascular wall thickening. This effect was associated with suppressions of erk2 mRNA expression and ERK1/2 phosphorylation in VSMCs and endothelial cells of the renal small arteries. It is concluded that inhibition of ERK1/2 ameliorates hypertension induced vascular remodeling in renal small arteries. 相似文献
97.
Fluorescence of leachates from three contrasting landfills 总被引:28,自引:0,他引:28
Landfill leachates are composed of a complex mixture of degradation products including dissolved organic matter, which includes a wide range of potentially fluorescent organic molecules and compounds. Here we investigate the excitation-emission matrix fluorescence of landfill leachates from three contrasting landfill sites. Landfill fluorescence properties are all characterized by intense fluorescence at lambda(ex) =220-230nm, and lambda(em) =340-370nm which we suggest derives from fluorescent components of the Xenobiotic Organic Matter fraction such as naphthalene, as well as at lambda(ex) =320-360nm, and lambda(em) =400-470nm from a higher molecular weight fulvic-like fraction. Landfill leachates are characterized by intense fluorescence, with approximately 10(2) intensity units of fluorescence at lambda(ex)=220-230nm, and lambda(em)=340-370nmmg(-1) of total organic carbon, demonstrating leachate detection limits of <0.1mgl(-1) total organic carbon. We demonstrate that for all landfill sites, leachate fluorescence intensity has a strong correlation with ground water quality determinants ammonia, total organic carbon and biochemical oxygen demand. We investigate both within-site and between-site leachate fluorescence properties, and demonstrate that although there is significant within-site variability, leachates from all 3 sites can be statistically discriminated using just fluorescence properties (65% success rate) or with a combination of fluorescence and basic geochemical parameters (85%). Our findings suggest that fluorescence can be used as a rapid and sensitive tracer of leachate contamination of ground water, as well as help discriminate, together with geochemical determinants, leachates from different landfill sources. 相似文献
98.
1993年英国自然安葬的兴起以及英国政府提议的坟墓再利用计划将对基地景观产生深远影响。长久以来,很多墓地因缺乏资金而疏于养护,致使其价值被低估。自然安葬的迅速发展一方面是对人们越来越关心的英国墓地疏于养护问题作出的直接回应,另一方面也与英国众多城市可用于传统殡葬的土地日益减少有关。在自然安葬不断发展改进的时候,"坟墓再利用"计划的再次引入将有利于防止墓地成为荒废空间。通过当前英国谢菲尔德大学景观系和社会学系正在进行的墓地研究,阐述自然安葬和坟墓再利用的发展以及它们对墓地景观产生的影响。 相似文献
99.
Chieh-Yuan Cheng Rong-Juin Shyu Der-Yuan Liou 《Journal of Mechanical Science and Technology》2007,21(12):2082-2090
The conventional SEA model considers only the resonant part of the structural response to an acoustic excitation. Therefore,
this study investigates non-resonant responses of isotropic and orthotropic plates to acoustically induced vibrations in a
reverberation chamber. A modified SEA model is introduced to predict the non-resonant plate response. The estimated non-resonant
and resonant responses are then compared with those obtained experimentally, and good agreement is observed for isotropic
and orthotropic plates. For an isotropic plate with a small dissipation loss factor, when the non-resonant part is ignored,
the estimated response can lead to significant errors at frequencies near and above the critical frequency, while large errors
may occur at frequencies below the critical frequency for an orthotropic plate with a high dissipation loss factor. The experimental
study indicates that the non-resonant response component should be included in the estimated responses to enhance predictive
accuracy. 相似文献
100.