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1.
《武汉大学学报:自然科学英文版》2015,(1)
Amino silicone resins were synthesized through a three-step method using(3-aminopropyl) triethoxysilane(APTES), methyltrimethoxysilane(MTMS) and end-capping agents, The products were characterized by Fourier transformed infrared spectroscopy(FT-IR), nuclear magnetic resonance(1H NMR), element analysis and gel permeation chromatography(GPC). The results of 1H NMR indicate that the chemical shift signal of acid-catalyzed products is weak at δ3.4(attributing to alkoxy). FT-IR shows that there is a vibration peak of Si—OH at 3 100-3 600 cm-1 and the intensity of the peaks is most weak at 6h. The results show that this method cannot only effectively reduce the residue of alkoxy groups and Si—OH groups, but also obtain the products with sufficient amino group. It concludes that this resin is suitable as modifier in the silicone rubber. 相似文献
2.
《东华大学学报(英文版)》2016,(1)
The coated fiberglass fabric was prepared to protect personnel and equipment from sparks, heat, and molten metals during hot work projects. Ferric oxide powder 2%,mica powder6%,wollastonite powder 4%,and white carbon black 8% were added in the phenyl methyl silicone to prepare the composite silicone solution. The french chalk and coupling agent can effectively solve the deposition of fillers in the coating solution. Compared with the original fiberglass fabric,heat resistance of the coated fabric under high temperature was greatly improved, and the temperature limitation in short period was higher than 900℃. Horizontal flammability tests showed that the coated fabric was non-combustible with no melting and no fragments. The temperature for long period usage of coated fabric was lower than 500 ℃. Welding drop test showed that the coating could prevent the molten metals,sparks and heat from transferring in the fabric. Test for toxic gas release showed that the toxic gases such as HCN,SO_2,HCl,and HF were not detected,only CO( 100 mg / m~3) and NO( 12 mg /m~3) were detected,and their concentrations were far lower than the limitation values CO( 4 375 mg / m~3) and NO( 134 mg /m~3). The breaking strength of coated fabric was almost twice the strength of the original fabric,and the coated surface had good water and oil repellency. 相似文献
3.
LI Jinsong CHEN Dayuan HAN Zhiming ZHU Ziyu WEN Duancheng SUN Qingyuan Liu Zhonghua WANG Minkang LIAN Li DU Jun WANG Pengyan ZHANG Hernin 《科学通报(英文版)》2002,47(6)
Interspecies somatic nuclear transfer (NT) may provide a new approach for preservation of the endangered rare species. Previous interspecies cloning studies have shown that a nucleus from a quiescent somatic cell supports early development of reconstructed embryos in the ooplasm from another species. In this study, we transferred nonquiescent somatic cells from a giant panda into the perivitelline space of the enucleated rabbit oocytes. After electrofusion (at the rate of 71.6%) and electrical activation, 4.2% of the panda-rabbit reconstructed embryos developed to blastocyst in vitro. For improving the development rate of reconstructed embryos, we used serial NT in this study, I.e. Blastomeres from reconstructed morulae were transferred into the perivitelline space of the enucleated rabbit oocytes. The fusion rates in the groups of serial Ⅰ, serial Ⅱ and serial Ⅲ were 79.5%, 84.1% and 78.0%, respectively, having no difference with that of somatic group. And the blastocyst rates in serial NT groups were 19.4%, 13.5% and 10.3%, respectively, which are significantly higher than that in somatic NT group. These results indicate that the nuclei from nonquiescent somatic cells can support early development of reconstructed embryos and serial NT can improve the development rate of interspecies reconstructed embryos. 相似文献
4.
WANGXuebin XUMuling LIBing LIDongfeng JIANGJinchang 《科学通报(英文版)》2003,48(22):2454-2457
The retained curve in one-trial passive avoidance task (OTPAT) of day-old chicks hatching from natural geomagnetic field (control groups) is consistent with the acknowiedged three-phase model. The two dips are at the 20th min and the 60 rain, and the avoidance rates (AR) to the red bead in short- and intermediate-term memory are 68.4% on average, while that in the long-term momory was 74.8%. The OTPAT retained curve of day-old chicks hatching from hypomagnetic field space (experimental groups) presents the marked timing effect. The two dips were at the 25th min and the 50th min, the avoidance rates to the red bead (ARt) in the short- and intermediate-term memory was 74.1% on an average, which was resembled to that in control group;however, the long-term memory appeared an obvious fluctuation. Compared with that in control groups, ARt and the deviation coefficient in experimental groups were decreased by 25.3% and increased by 1.3 times, respectively. That is to say, both the memory ability and stability in the experimental chicks declined. The result shows that the hypomagnetic field space has a negative effect on the development of chick brain function, and that cannot be negligible. 相似文献
5.
Relationships between changes of kernel nutritive components and seed vigor during development stages of F1 seeds of sh
2 sweet corn 总被引:2,自引:0,他引:2
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Dong-dong Cao Jin Hu Xin-xian Huang Xian-ju Wang Ya-jing Guan Zhou-fei Wang 《浙江大学学报(自然科学英文版)》2008,9(12):964-968
The changes of kernel nutritive components and seed vigor in F1 seeds of sh2 sweet corn during seed development stage were investigated and the relationships between them were analyzed by time series regression (TSR) analysis. The results show that total soluble sugar and reducing sugar contents gradually declined, while starch and soluble protein contents increased throughout the seed development stages. Germination percentage, energy of germination, germination index and vigor index gradually increased along with seed development and reached the highest levels at 38 d after pollination (DAP). The TSR showed that, during 14 to 42 DAP, total soluble sugar content was independent of the vigor parameters determined in present experiment, while the reducing sugar content had a significant effect on seed vigor. TSR equations between seed reducing sugar and seed vigor were also developed. There were negative correlations between the seed reducing sugar content and the germination percentage, energy of germination, germination index and vigor index, respectively. It is suggested that the seed germination, energy of germination, germination index and vigor index could be predicted by the content of reducing sugar in sweet corn seeds during seed development stages. 相似文献
6.
《东华大学学报(英文版)》2017,(4)
The in-plane tensile behaviors of bi-axial warp-knitted(BWK) composites under quasi-static and high strain rates loading were experimentally analyzed in this article. The tensile tests were conducted along warp direction( 0°) and weft direction( 90°) at quasi-static rate of 0. 001 s~(-1) and high strain rates ranging from 1 450 to 2 540 s~(-1),respectively. It is found that the significant strain rate sensitivity can be observed in the stress-strain curves of BWK composites. The fracture morphologies of BWK composites demonstrate that the tensile failure modes are shear failure and fiber breakage under the quasi-static testing condition while interface failure and fibers pullout are at high strain rates. 相似文献
7.
Concrete cylinders wrapped with glass fabrics of various constructions were fabricated. Compressive behaviours of cylinders with and without fabric wrapping were investigated. Comparisons of the compressive characters while using different fabrication parameters were made. It was demonstrated that the effect of the fabric reinforcement was obvious. The tensile strength of the filament used in the fabric played an important role as far as the anti-compression behaviour of the reinforced cylinders is concerned. 相似文献
8.
A new entire biodegradable scaffold has been developed which does not require precelluiarization before transplantation. This new kind of vascular scaffold prototype made from porous poly- e-caprolactone (PCL) membrane to provide three-dimensional environment for cell growth, and embedded with weft-knitted polylactic acid (PLA) fabric to support mechanics. The aim of this paper is to study the variation tendency of mechanical properties with the fabric spacing changing. The basic geometrical parameters were measured to characterize properties of the samples. The tensile and compressive elastic recovery of the samples were tested by the universal mechanical tester and radial compression apparatus, respectively. Both tensile and compressive properties enhanced when reducing the fabric spacing of the composite vascular scaffold. 相似文献
9.
A new instrument based on light projection and image analysis techniques for assessing fabric pilling is presented. This system can automatically detect the pills from the successive sections of the fabric surface, which can make up for the limitation of both the gray level image -analysis techniques and laser triangulab'on techniques. The test of a large number of worsted wool fabric samples shows that it can objectively characterize the degree of pilling by using fuzzy sets and has good accordance with human visual inspection. 相似文献
10.
Comparison of an SMS text messaging and phone reminder to improve attendance at a health promotion center: A randomized controlled trial
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Objective: To compare the efficacy of a short messaging service (SMS) text messaging and phone reminder to improve attendance rates at a health promotion center. Methods: A total of 1 859 participants who had scheduled appointments in the health promotion center of our hospital from April 2007 to May 2007 were enrolled in the study and randomly assigned into 3 groups: control (no reminder) group, SMS text messaging reminder group and telephone reminder group. Attendance rates and costs of interventions were collected. Results: A total of 1848 participants were eligible for analysis. Attendance rates of control, SMS and telephone groups were 80.5%, 87.5% and 88.3%, respectively. The attendance rates were significantly higher in SMS and telephone groups than that in the control group, with odds ratio 1.698, 95% confidence interval 1.224 to 2.316, P=0.001 in the SMS group, and odds ratio 1.829, 95% confidence interval 1.333 to 2.509, P〈0.001 in the telephone group. However, there was no difference between the SMS group and the telephone group (P=0.670). The cost effectiveness analysis showed that the cost per attendance for the SMS group (0.31 Yuan) was significantly lower than that for the telephone group (0.48 Yuan). Conclusion: SMS and telephone are effective reminders for improving attendance rate at a health promotion center. SMS reminder may be more cost-effective compared with the telephone reminder. 相似文献
11.
本文通过添加不同整理剂对兔羊毛精纺针织品进行防掉毛、防起球研究。12种处理方案的掉毛改善率为6.7~66.7%,起球改善率为9.3%~73.5%,织物风格变化从1级到5级。为全面、客观、定量地对经各种处理工艺后,织物的起球程度、掉毛量及织物风格作综合评价,提出了综合评定值。丙烯酸酯树脂处理组综合评定值较低,3号硅酮树脂处理组综合评定值较高,其中处理液浓度为7%的3号硅酮处理组,织物风格基本不变,起球改善率与掉毛改善率分别为53%和62%,(按GB4802.3-84标准测试与评定,起球达4.5级),且耐水洗性能良好。 相似文献
12.
起球是影响织物服用性能的主要因素之一。本文采用YG502型园轨迹织物起毛起球仪,对50/50兔羊毛机织物进行磨球,并通过投影显微镜观察磨球次数与球体结构形态、球体密度和数量的关系,同时,就起球的影响因素,包括茸毛高度、定型程度、以及化学树脂整理剂及柔软剂进行研究。显微镜观察发现,50/50兔羊毛机织物球体中2/3以上纤维是兔毛纤维,而球芯则以较粗的羊毛纤维为多。为综合考虑球体大小、数量和纤维纠缠密度对感官的影响,提出了起球程度评价指标——等价面积值,其较传统五级分类法更为客观,准确。 对织物起球过程的研究表明,由茸毛转为球体的临界磨球次数为10~20次;磨球20~200次是球体大量形成时期;之后球体形成减少;磨球1000次以后落球开始。此规律可由起球曲线反映。试样经优化处理后,其起球曲线变化趋势基本不变,但绝对值与相对变化率均较原样对应值为小。 本研究显示定形与起球关系不明显;降低绒毛高度、添加一定浓度的树脂对减少起球效果明显,柔软剂的添加则可增加起球机会。此实验结果对生产上正确应用剪毛工艺、树脂和柔软剂添加与保持优良织物外观和手感的关系处理具有重要的指导意义。 相似文献
13.
选用一种低温环保型水性丙烯酸酯共聚乳液,对羊毛纬平针织物进行了抗起毛起球的整理,研究了整理剂质量浓度、浴比、时间、温度4个因子对羊毛纬平针织物整理效果的影响.根据正交实验得出较优工艺参数为:整理剂质量浓度30g/L、浴比1:35、温度50℃、时间30min.经该工艺整理后可提高羊毛纬平针织物的抗起毛起球性能和织物强力. 相似文献
14.
用纳米氧化锌与水溶性聚氨酯配制功能整理剂,其中粒径100nm以下的纳米氧化锌粒子达到95.22%.研究其对棉、丝织物抗皱、抗紫外线及抗菌的性能,结果表明:整理后的棉、丝织物回复角提高,抗皱性改善,且有较好的强力及白度保持率;经纳米氧化锌水溶性聚氨酯整理剂整理的纯棉织物,10次水洗后的紫外防护因子(UPF)等级达到50 ,整理剂放置30d后,再经轧烘焙整理织物的UPF保持率分别为95.39%和95.11%,UPF等级保持不变,整理后的棉织物有明显的抗大肠杆菌抑菌圈. 相似文献
15.
探讨了应用图像分析技术对织物起球进行客观的等级评估.首先介绍了应用Wold分解纹理模型从织物图像中分离出毛球信息,然后对提取的毛球信息进行阈值化处理,再以毛球的面积百分比、总数和分布等三个特征指标对起球等级进行客观评估.运用上述技术途径对素色、印花及色织的简单与复杂组织等7种织物样品进行起球等级的客观评估,结果与专家的人工主观评定极为吻合. 相似文献
16.
曾泳春 《东华大学学报(自然科学版)》1995,(4)
本文讨论了起球对兔羊毛针织物损伤的影响。通过实验我们发现掉毛和掉球从兔羊毛针织物表面移去了大量纤维,造成织物损伤。用球的增长机理解释了起球大大超过初始绒毛量的现象,从而说明起球不只是影响兔羊毛针织物的美观,更是一种磨损机理。 相似文献
17.
王晓明 《湖南工程学院学报(自然科学版)》2004,14(2):78-80
从棉织物产生折皱的原因,柠檬酸(CA)和2D树脂与棉纤维反应机理,分析比较了活性染料染色的棉织物,分别用柠檬酸和2D树脂整理后,折皱回复性、染色牢度的变化. 相似文献
18.
首先采用图像分析技术对起球织物的图像进行预处理;其次以织物起球总面积M和起球形态S等指标定量地综合评价织物的起球状况;最后以针织物为例,通过实验验证此方法的可行性. 相似文献
19.
探讨细粘胶纤维和细涤纶纤维低号纱混纺织物连续化生产的可行性.运用松式、低张力和短流程的连续式印染加工方法,生产出了具有防缩免烫和仿丝绸效果的高档粘涤织物,总结出了一套较为成功的细纤维低号纱粘涤织物染整工艺. 相似文献
20.
应用整理剂HF-1通过后整理方式赋予涤纶长丝织物吸湿排汗性能,提高涤纶织物的穿着舒适性,改善织物手感和服用性能.通过对涤纶织物吸湿排汗性能整理工艺的研究,确定出涤纶织物应用整理剂HF-1进行吸湿排汗整理的最佳工艺条件.对整理后织物的毛细效应综合值、导湿综合值、干燥速率及耐洗性进行测试,结果表明,经整理剂HF-1整理后的... 相似文献