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101.
102.
利用原子吸收光谱测定法(AAS)对甘肃岷县地区的25只黑裘皮羊毛中的锌、铜、镉、铁、锰、镁、钴7种微量元素含量进行了测定,分析了其变异程度和代表性,以及矿物元素与羊类疾病的关系。结果表明,铜、锰、钴、镉的标准差相对较小,其平均值代表性较强;锌、铁、镁标准差相对较大,其平均值代表性较差。为相关研究提供参考数据,在兽医临床中具有实用价值。 相似文献
103.
Sara Paolella Mariangela Bencivenni Francesca Lambertini Barbara Prandi Andrea Faccini Cinzia Tonetti Claudia Vineis Stefano Sforza 《Journal of mass spectrometry : JMS》2013,48(8):919-926
In the present paper, a proteomic method for species determination in fibres has been developed. Keratin was extracted from yak, wool and cashmere fibres and digested by trypsin, providing peptide mixtures that were analyzed by liquid chromatography coupled with electrospray mass spectrometry (LC/ESI‐MS) in order to identify peptidic species‐specific markers able to differentiate the fibres. Several suitable peptide markers were identified and validated in different fibres of different origin and having undergone different technological treatments, showing 100% specificity and 100% selectivity. Most of the peptide markers were also identified by means of high‐resolution mass spectrometry, confirming the origin from species‐specific keratin sequences. Some peptides were also used for the quantification of the different species in mixed fibres by LC/ESI‐MS. Validation experiments and blind tests confirmed their ability to act as very specific quantitative and qualitative markers. The method here developed is a valid complement to the standard benchmark methods for fibre identification and quantification and will be very useful for assessing the authenticity of textile products. Copyright © 2013 John Wiley & Sons, Ltd. 相似文献
104.
Summary: Wool fabrics were treated with keratin hydrolysate in isolated systems, in systems incorporating a cross-linking enzyme, and in systems with nanoparticle silver. The dimensions of wool fabric were controlled after keratin applications and the strength of bleached wool fabric was improved. Keratin applications imparted these improved properties when applied alone and when applied with the enzyme. The enzyme was effective for in-situ, solid-state cross-linking of wool fabric, cross-linking keratin-to-keratin, and cross-linking keratin-to-fabric. To further improve the properties of wool, nanoparticle silver was produced in various shapes. Transmission electron microscopy (TEM) micrographs of these particles showed discrete and isolated particles of size 8-100 nm, dependent on the preparation. A combination of TEM and UV-VIS spectroscopy was used to characterize these particles and scanning electron microscopy running in backscattered electron mode confirmed their placement on wool fibers. The application of nanoparticle silver to wool when co-added with keratin may both improve dimensional stability and impart antimicrobial efficacy. 相似文献
105.
Sheep on the island of North Ronaldsay (Orkney, UK) feed mostly on seaweed, which contains high concentrations of dimethylated arsenoribosides. Wool of these sheep contains dimethylated, monomethylated and inorganic arsenic, in addition to unidentified arsenic species in unbound and complexed form. Chromatographic techniques using different separation mechanisms and detectors enabled us to identify five arsenic species in water extracts of wool. The wool contained 5.2 ± 2.3 µg arsenic per gram wool. About 80% of the arsenic in wool was extracted by boiling the wool with water. The main species is dimethylarsenic, which accounted for about 75 to 85%, monomethylated arsenic at about 5% and the rest is inorganic arsenic. Depending on the separation method and condition, the chromatographic recovery of arsenic species was between 45% for the anion exchange column, 68% for the size exclusion chromatography (SEC) and 82% for the cation exchange column. The SEC revealed the occurrence of two unknown arsenic compounds, of which one was probably a high molecular mass species. Since chromatographic recovery can be improved by either treating the extract with CuCl/HCl (CAT: 90%) or longer storage of the sample (CAT: 105%), in particular for methylated arsenic species, it can be assumed that labile arsenic–protein‐like coordination species occur in the extract, which cannot be speciated with conventional chromatographic methods. It is clear from our study of sheep wool that there can be different kinds of ‘hidden’ arsenic in biological matrices, depending on the extraction, separation and detection methods used. Hidden species can be defined as species that are not recordable by the detection system, not extractable or do not elute from chromatographic columns. Copyright © 2003 John Wiley & Sons, Ltd. 相似文献
106.
Farzaneh Ebrahimgol Hossein Tavanai Farzaneh Alihosseini Taghi Khayamian 《先进技术聚合物》2014,25(9):1001-1007
This work reports on producing wool keratin nanoparticles through electrospraying. Wool keratin is a natural biodegradable and biocompatible protein. Keratin powder has found application in hygiene, cosmetics, filtration, tissue engineering scaffolds, and controlled drug release. Like other nano materials, the performance of keratin in submicron size range changes drastically. Electrospraying is a technique that is capable of producing nanosized, regular, and spherical particles. To prepare the electrospraying wool keratin solution, keratin was recovered from descaled wool fibers by dissolving it in mercaptoethanol first, and keratin sponge was obtained. Then, the keratin sponge was dissolved in formic acid that provided the electrospraying solution. This research involved primarily an investigation on the effect of important electrospraying conditions such as polymer concentration, feed rate, voltage, and nozzle‐collector distance on the average particle size of the electrosprayed nanoparticles. The results showed that the proper concentration of keratin in formic acid for the electrospraying keratin nanoparticle was about 0.5% (w/v). As far as electrospraying conditions are concerned, decreasing feed rate and increasing nozzle‐collector distance led to lower average particle size. Voltage did not show a practically significant effect on the average particle size. The average size of the electrosprayed keratin nanoparticles fabricated in this work lies in the range of 36–72 nm. Fourier transform infrared Fourier transform infrared (FTIR) spectra showed that electrosprayed keratin nanoparticles contain –SO2–S– and –SO–S– linkages. Copyright © 2014 John Wiley & Sons, Ltd. 相似文献
107.
108.
《Journal of separation science》2017,40(4):858-868
The goal of this work was to determine the microbial volatile organic compounds emitted by moulds growing on wool in search of particular volatiles mentioned in the literature as indicators of active mould growth. The keratinolytically active fungi were inoculated on two types of media: (1) samples of wool placed on broths, and (2) on broths containing amino acids that are elements of the structure of keratin. All samples were prepared inside 20 mL vials (closed system). In the first case (1) the broths did not contain any sources of organic carbon, nitrogen, or sulfur, i.e. wool was the only nutrient for the moulds. A third type of sample was historical wool prepared in a Petri dish without a broth and inoculated with a keratinolytically active mould (open system). The microbial volatiles emitted by moulds were sampled with the headspace solid‐phase microextraction method. Volatiles extracted on solid‐phase microextraction fibers were analyzed in a gas chromatography with mass spectrometry system. Qualitative and quantitative analyses of chromatograms were carried out in search of indicators of metabolic activity. The results showed that there are three groups of volatiles that can be used for the detection of active forms of moulds on woollen objects. 相似文献
109.
非离子表面活性剂在洗毛中的应用 总被引：1，自引：0，他引：1
介绍了非离子表面活性剂的特点，通过对比分析，使用非离子洗剂洗毛，对洗净毛质量有较大程度的提高，且洗毛废水容易处理，是理想的洗毛用剂。 相似文献
110.
李毅 《济南大学学报(自然科学版)》1992,(3)
根据笔者近年来从事岩棉生产线电气系统设计的经验,对目前国内引进的岩棉生产线主传动电气控制系统,特别是主传动系统的结构及控制器的设计原则作一简要分析,并提出了一种基于单片机的新型主传动控制器。 相似文献