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181.
182.
In this study, we attempted to evaluate a novel use of sericin-fixed silk fiber (SFx) as an immobilization support of enzyme.
Sericin was fixed on the silk fiber using glutaraldehyde as a fixation reagent. After 6 hours of fixation, the degree of fixation
increases linearly with linear decrease of the amount of bound α-chymotrypsin (CT). This suggests that the increase of the
degree of fixation is due to the further crosslinking of free aldehyde groups on the surface of sericin-fixed silk fiber (SFx).
Even though perfect fixation was not achieved, sericin did not dissolve seriously and could be removed by further washing.
The specific activity did not differ significantly after 6 hours of fixation. The activity of immobilized CT on SFx decreased
to its half after 6 hours of incubation at 50°C. However, it retained 78% of initial activity even after 1 hour of treatment
with 100% ethanol. As a result, the SFx could be used as an immobilization support of enzyme in non-aqueous media at ambient
temperature. 相似文献
183.
S. Shahidi M. Ghoranneviss B. Moazzenchi A. Rashidi D. Dorranian 《Fibers and Polymers》2007,8(1):123-129
The low temperature plasma (LTP) technique is used widely to modify polymer and textile materials. This paper describes the
development of a plasma system for textile treatment. Polypropylene (PP) has a very low value of the surface free energy (approximately
20–25 mJ/m2). Due to low surface energy, Polypropylene has very weak hydrophilic properties. By controlling the plasma variables, such
as the nature of gas, the discharge power, the pressure and the exposure time, a great variety of surface effects can be generated.
In this paper, we report the effect of cold plasma of O2 and N2 gases at various time of exposure on the dyeing and physical properties of PP fabrics. The results show a significant increase
in the color depth upon dyeing after treating PP fabrics with low temperature plasma of O2 and N2. For comparing the amount of fabrics dye exhaustion, we have used reflective spectrophotometer. The morphology of the modified
surfaces has also been investigated using scanning electron microscopy (SEM). And also FTIR was used to examine the functional
groups of the corresponding samples. 相似文献
184.
The effect of casting solvent on the structural characteristics and miscibility of regenerated silk fibroin/Poly(vinyl alcohol) blends 总被引:1,自引:0,他引:1
Regenerated silk fibroin(SF)/Poly(vinyl alcohol)[PVA] blend films were prepared using different casting solvents, water and
formic acid, to elucidate the effect of casting solvent on the structure and miscibility of SF/PVA blends. FTIR and XRD measurement
suggested thatβ-sheet conformation of SF was not changed by addition of PVA in case of formic acid casting and the casting solvent determined
the crystallized component of SF/PVA, leading to a different trend in the overall crystallinity between the two blends. The
casting solvent had a dominant role in deciding phase behavior and molecular miscibility of blend films. SEM observation and
DMTA measurement elucidated that water solvent produced phase-separated blend films while formic acid yielded one phase blend
films with partial miscibility in molecular level indicating that the miscibility of SF blend can be improved by choosing
a proper co-solvent. 相似文献
185.
186.
This paper deals with the grey fabric deformation during relaxation. It investigates the effect of twist direction and twist
liveliness on the 2/2 twill weave woven fabric distortion, during relaxation This experimental work shows that twist liveliness
increases the natural tendency of the twill weave woven fabric to skew. In addition when the twist direction of the warp and
weft is opposite to each other the bias curling occurs too. 相似文献
187.
农民合作经济组织是降低交易成本、推动农业产业化和专业化分工、提高农民组织化程度和福利水平的有效组织形式。文章基于对安徽茧丝绸产业合作经济组织的实地调查,对农民合作经济组织的经济绩效和运作模式进行分析,并提出合作经济组织发展的相应制度安排。 相似文献
188.
天然纤维织物双轴向拉伸力学性能影响因素的研究 总被引:2,自引:0,他引:2
采用数字散斑相关方法对苎麻纤维织物双轴向拉伸试验中力学性能的影响因素进行探讨,得出如下结论:选取预张力≤10N、拉伸速率≤0.125mm/s,平缓圆弧过渡连接的十字试件作为双轴向拉伸试验条件比较合适;随着X、Y轴向与经、纬向夹角的增加,最大断裂强力值变小,断裂伸长率变大,经、纬向载荷的相对差值变小且在45°时经、纬向断裂载荷变化趋于一致。 相似文献
189.
190.
三眠蚕可生产特殊用途的超细纤度茧丝。采用眠性稳定的三眠蚕品种和综合经济性状优良的现行生产用四眠蚕品种作亲本进行杂交,选择培育了综合经济性状良好且眠性稳定的强健性三眠蚕中系育种材料三、龙和日系育种材料汇、泉、源、景。经配合力测定和组合筛选,初步选配出的三眠蚕四元杂交组合三·龙×汇·源具有强健好养、眠性稳定、茧丝纤度细、茧丝品质优的特点:三眠率达到98%以上,全龄经过较四眠蚕亲本短1-2 d,茧丝纤度1.75~2.22 dtex,一粒茧丝长1 000~1 200 m,解舒率70%~85%,洁净93~95分。三眠蚕四元杂交组合三.龙×汇.源在农村试养同样表现出眠性稳定、强健好养的特点,适合在华南蚕区推广应用。 相似文献