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排序方式: 共有501条查询结果,搜索用时 15 毫秒
1.
《Composite Interfaces》2013,20(5):469-478
The effect of carbon fiber textile for flexural reinforcement to deteriorated reinforced concrete floor slab is tested in laboratory by cutting out six specimens from existing structure aged more than 70 years. The repair method between concrete and carbon fiber textile is used as experimental parameter. From the test results, deformation, bond characteristic of carbon fiber textile and the applicability of carbon fiber textiles to flexural reinforcement of floor slabs are discussed. 相似文献
2.
纳米技术及其在纺织上的应用 总被引:1,自引:0,他引:1
夏涛 《新疆大学学报(理工版)》2002,19(2):251-253
对纳米技术的基本情况进行了论述,同时详细介绍了纳米材料和技术在纺织纤维材料加工方面的应用领域和产品特点,指出在纺织上利用纳米技术对于研究,开发、生产新一代的功能性化学纤维织物,绿色环保织物,扩大纺织品的应用范围,应对国际市场具有积极意义。 相似文献
3.
We describe two methods to impart the water repellency for the surface of cotton fabric, using a commercially available and a laboratory synthesized fluoroalkylsiloxanes. To characterize the wettability and the durability of water repellent properties of hydrophobic coating produced, we have studied the advancing water contact angles, rolling angles and the evolution of water contact angle in time during a continuous contact of the surface with the water drop. The quality of the coatings was also assessed after the washing procedure. The analysis of the wettability of hydrophobized fabrics indicated that a better effect, leading to the superhydrophobic state of the surface, was observed when the surface relief of the fabric with the coating is determined by not only the structure and braiding of the fabric, but also the additional elements of texture created by the aggregates of molecules of hydrophobic agent. 相似文献
4.
We studied the adsorption behaviour at the liquid/air and liquid/solid interface of a new anionic surfactant derived from sugar, the sodium decyl galacturonate. The surface tension of aqueous solutions, measured in equilibrium and as a function of time, is particularly affected by the presence of decanol, synthesis residue, which amount ranges between about 0 and 13%. The surface tension lowering is accelerated in presence of decanol, owing to its rapid diffusion to the interface or/and because it affects the mobility and adsorption process of the anionic surfactant molecules. The wetting power of surfactant solutions were also investigated in relation with textile treatment applications. We measured the kinetics of absorption of surfactant solutions in a piece of standard cotton and compared it to the absorption of pure decanol, a completely wetting liquid and to the absorption of an alkylpolyglucoside. The time at which the fabric piece is saturated appears to be related to the adsorption of surface-active molecules on the fibers at the advancing liquid front/fabric contact line. Decanol was found to promote absorption and micellar life-time seem to reflect the differences observed at high concentration. This study shows the importance of controlling the amount of surface-active residues which may alter the kinetics of surfactant adsorption, particularly in industrial processes where equilibrium conditions are not reached. 相似文献
5.
Alexander V. Gusakov Arkady P. Sinitsyn Alejandro G. Berlin Nonna N. Popova Alexander V. Markov Oleg N. Okunev Dmitry F. Tikhomirov Mark Emalfarb 《Applied biochemistry and biotechnology》1998,75(2-3):279-293
A model microassay system was developed to measure indigo backstaining on cotton fabrics in the presence of enzymes on a small
laboratory scale. Backstaining indexes for 11 cellulase samples were measured, and the enzymes were ranked from lower to higher
backstaining. Two multienzyme cellulase preparations were separated into fractions using chromatofocusing on a Mono P column.
Adsorption ability and backstaining properties of purified enzyme fractions were studied. Evidence was obtained that protein
adsorption on cotton fabrics is a crucial parameter causing backstaining (both for crude cellulase samples and purified enzyme
components). 相似文献
6.
Simon Knig Philipp Kreis Leonie Reinders Ronald Beyer Andreas Wego Christian Herbert Mark Steinmann Erik Frank Michael R. Buchmeiser 《先进技术聚合物》2020,31(8):1827-1835
The primary use of poly(acrylonitrile) (PAN) fibers, commonly referred to as acrylic fibers, is in textile applications like clothing, furniture, carpets, and awnings. All commercially available PAN fibers are processed by solution spinning; however, alternative, more cost‐effective processes like melt spinning are still highly desired. Here, the melt spinning of PAN‐co‐poly(methyl acrylate) (PMA) plasticized with propylene carbonate (PC) at 175°C is reported. The use of methyl acrylate (MA) as comonomer and PC as an external plasticizer renders the approach a combination of internal and external plasticization. Various mixtures of PAN and PC used in this work were examined by rheology, subjected to melt spinning, followed by discontinuous and continuous washing, respectively. The best fibers were derived from a PAN‐co‐PMA copolymer containing 8.1 mol‐% of MA having a number‐average molecular weight M n of 34 000 g/mol, spun in the presence of 22.5 wt.‐% of PC. The resulting fibers were analyzed by scanning electron microscopy and wide‐angle X‐ray scattering (WAXS), and were subjected to mechanical testing. 相似文献
7.
高效液相色谱-电喷雾串联质谱法快速测定纺织品中苯氧羧酸类除草剂残留量 总被引:5,自引:2,他引:5
建立了纺织品中7种苯氧羧酸类除草剂的高效液相色谱-电喷雾串联质谱(LC-ESI-MS/MS)快速检测方法.样品经甲酸酸化的丙酮溶液超声提取两次,无需其它净化过程.液相色谱使用C18反相色谱柱,流动相为醋酸铵水溶液和甲醇,在梯度条件下分析.在选择反应检测(SRM)负离子模式下进行质谱信号采集,采用两对同位素离子对进行定性和定量分析.选取3种有代表性的纺织品进行方法检出限(LOD)、定量限(LOQ)、线性、回收率和精密度的验证.方法的LOQ为 0.9~2.4 μg/kg; 回收率为85%~106%; 相对标准偏差为2%~11%.本方法简便、有效、可靠、灵敏,能够满足国际生态纺织品标准(Oeko-Tex Standard 100)的限量要求,适用于纺织品中苯氧羧酸类除草剂的日常检测及确证. 相似文献
8.
Katja Kavkler ?iga Šmit David JezeršekDiane Eichert Andrej Demšar 《Polymer Degradation and Stability》2011,96(6):1081-1086
We have examined specimens of historical biodeteriorated cellulose textiles using synchrotron radiation and conventional source FTIR spectroscopy. The main aim of our research was to investigate structural changes caused by ageing and biodeterioration in different types of cellulose fibres. We compared the results, obtained with both methods regarding spectral quality and information obtained with each method. Additionally, we obtained mapping images of the cross sections of the investigated specimens using synchrotron FTIR in order to analyze structural changes in cross sections, caused due to biodeterioration. 相似文献
9.
The present paper aims to investigate the efficiency of thermal activation persulfate in eliminating the organic dye “Basic Fuchsin” (BF). In addition, the study attempts to elucidate the effect of different operating parameters, such as persulfate dosage (0.44–4.4 mM), the initial solution pH of (3–10), and temperature (25–50°C), on the process. The effects of various anions and water matrices on BF discoloration were investigated. Thus, the findings revealed that 94.15% of BF can be eliminated using persulfate at a concentration of 4.4 mM and a temperature equal to 50°C. It occurs under the following operating conditions: oxidation time of 60 min, initial pH equal to 6, the pollutant concentration of 10 ppm, and stirring speed equal to 300 rpm. Furthermore, the kinetic study indicated that the degradation of the BF dye using PS followed a first-order pattern with rate constants varying within a range of 15.3 × 10−3–43.2 × 10−3 min−1. Based on the Arrhenius equation, the activation energy of the studied process was determined to be 29 kJ mol−1, suggesting that a moderate activation energy is required for BF discoloration. The results of the thermodynamic study confirm that the oxidation process is non-spontaneous and endothermic. Coexisting inorganic anions delayed BF discoloration to varying degrees, and the inhibitory action followed the following order: carbonate > chloride > sulfate > nitrate. Organic pollutants oxidation by the thermal activation of the persulfate is a simple and effective method for the depollution of waste textile water. 相似文献
10.
周启澄 《东华大学学报(自然科学版)》1994,(3)
中国和日本的近代毛纺织工业都是在19世纪80年代从西方引进的。但今天日本按人口平均的毛纺织生产能力已为中国的10倍。这两国毛纺织工业的宏观发展都可分为4个阶段:①1913年以前的初创阶段;②1914~1936年的奠基阶段;⑧1937~1949年的曲折阶段;④1950以后的成长阶段。但微观分析可见,这两国之间存在许多差异,本文简要地描述了这些差异。通过这种对比,可得出近代毛纺织工业发展的若干共同规律。 相似文献