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51.
This paper deals with the dyeing of cotton fabrics with microwave irradiation.The compara-tive experiments of the microwave dyeing to the conventional dyeing were carried out and themechanism was also discussed.Being subjected to microwave irradiation,the penetration of dyesand chemicals into the fabric can be achieved in a short time with a good color yield.The irradiatedmaterials generate heat via dielectric heating by high frequency electro-magnetic field and as a re-sult,energy saving can be realized.Based on the examination and analysis with X-ray diffraction,IR,SEM,and XPS,the reduction in crystallinity,the formation of active carbonyl groups of freeradicals containing oxygen and the morphological changes in the irradiated cottom fibers werefound.All of these may be believed in favour of the dyeing process. 相似文献
52.
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54.
Dynamics of proteins in Golgi membranes: comparisons between mammalian and plant cells highlighted by photobleaching techniques 总被引:5,自引:0,他引:5
In less than a decade the green fluorescent protein (GFP) has become one of the most popular tools for cell biologists for the study of dynamic processes in vivo. GFP has revolutionised the scientific approach for the study of vital organelles, such as the Golgi apparatus. As Golgi proteins can be tagged with GFP, in most cases without altering their targeting and function, it is a great substitute to conventional dyes used in the past to highlight this compartment. In this review, we cover the application of GFP and its spectral derivatives in the study of Golgi dynamics in mammalian and plant cells. In particular, we focus on the technique of selective photobleaching known as fluorescence recovery after photobleaching, which has successfully shed light on essential differences in the biology of the Golgi apparatus in mammalian and plant cells. 相似文献
55.
YUANQunhui LUJun WANLijun BAIChunli 《科学通报(英文版)》2004,49(24):2590-2593
Self-assembled structures of 3,4,5-tris-dodecy-loxy benzoic acid methyl ester (E12), 3,4,5-tris-tetradecy-loxy-benzoic acid methyl ester (E14) and their mixture (E12/E14) have been studied on HOPG by scanning tunneling microscopy (STM). Dimer-like patterns induced by dipole-dipole interaction are observed in E12 and E14 monolayers. The molecules form close-packed rows and interdigitate with the alkyl chains in adjacent molecules. The structural differences are proposed to be from the different length of substituted alkyl chains. Owing to similar adsorption energy, phase separation is observed in the E12 and E14 mixed adlayer with different domains. 相似文献
56.
The scanning tunneling microscopy(STM) and the atomic force microscopy(AMF) have been applied to the direct study of the adsorption and aggregation of β-amyloid(1-42)(Aβ42)on the hydrophobic graphite surface.It was found that Aβ42 were preferentially adsorbed on graphite defects such as the edges.Aβ42 peptides self-assembled into intermediate protofibrils,which in turn self-associated to form fibrils.Usually,two or more fibrils intertwined to form the helical structure.These results will provide an important clue to studying the aggregation process of β-amyloid. 相似文献
57.
LIN Yi SHEN XinCheng WANG JingJing BAO Lei ZHANG ZhiLing PANG DaiWen 《科学通报(英文版)》2007,52(23):3189-3192
Based on tapping mode AFM imaging, a method was demonstrated to evaluate compression elasticity of single double-stranded DNA (dsDNA) molecules in the force region. With images under ambient conditions, Young's moduli of dsDNA in compression were calculated. Results demonstrated that Young's moduli of dsDNA can be simply deduced according to the proposed model. The method can also be used to evaluate the compression elasticity of similar soft nanomaterials. 相似文献
58.
Control of blend morphology at multi-scale is critical for optimizing the power conversion efficiency (PCE) of plastic solar cells. To better understand the physics of photoactive layer in the organic photovoltaic devices, it is necessary to gain understanding of morphol- ogy and the corresponding electronic property. Herein we report the correlation between nanoscale structural, electric properties of bulk heterojunction (BHJ) solar cells and the annealing-induced PCE change. We demonstrate that the PCE of BHJ solar cells are dramatically improved (from 1.3 % to 4.6 %) by thermal annealing, which results from P3HT crystalline stacking and the PCBM aggregation for interpenetrated network. The similar trend for annealing- induced photovoltage and PCE evolution present as an initial increase followed by a decrease with the annealing time and temperature. The surface roughness increase slowly and then abruptly after the same inflection points observed for photovoltage and PCE. The phase images in electric force microscopy indicate the optimized P3HT and PCBM crystallization for interpenetrating network formation considering the spectroscopic results as well. From the correlation between surface photovoltage, blend morphology, and PCE, we propose a model to illustrate the film structure and its evolution under different annealing conditions. This work would benefit the better design and optimization of the morphology and local electric proper- ties of solar cell active layers for improved PCE. 相似文献
59.
李正瀛 《华中科技大学学报(自然科学版)》1989,(5)
本文采用脉冲漂移管-质谱仪方法研究了SF_6混合气体放电生成的SO_2气体的预放电参数,包括吸附系数、吸附速率、负离子迁移率、负离子种类和质量,并且测量了SO_2-O_2中不同负离子电流的变化关系. 相似文献
60.
L. Barsanti V. Passarelli P. Gualtieri 《Cellular and molecular life sciences : CMLS》1990,46(3):255-256
Summary In vivo microspectroscopy represents an effective and reliable technique to study pigment composition and distribution. In contrast to traditional extractive techniques, it preserves the integrity of biological specimens, without modifying the nature of the pigments. The spectroscopic apparatus we used is very simple and consists of a common microscope equipped with a monochromator, a photomultiplier, and two pinhole diaphragms. Absorption spectra obtained by means of this apparatus on different species of cyanobacteria are presented. 相似文献