超声波在洗毛中的应用

研究了不同条件下的超声波洗毛效果,并与传统乳化洗毛进行了对比.研究结果表明,利用超声波洗毛可以降低洗毛温度、缩短洗毛时间、降低洗剂和助剂用量.利用超声波所得的洗净毛蓬松性好,羊毛之间不发生纠缠,白度高且洗净毛中几乎无细小杂质.另外,超声波在洗毛的同时,对羊毛鳞片有蚀刻作用.经过超声波洗毛所得洗净毛纤维鳞片变钝、变光,摩擦效应降低.且超声波洗毛所得洗净毛纤维细度分布更趋集中,长时间超声波洗毛会使羊毛纤维直径变小,断裂伸长增大,但对纤维断裂强力无明显损伤.     

Equilibrium and Kinetic Study of Sericin Protein Absorption onto Anion-Exchangable Fibers

Silk is made of sericin and fibroin proteins.The sericin constitutes 20%-30% of silk proteins and it covers the fibroin.Sericin is usually treated as impurity and removed during the process of degumming in dyeing and printing factories.However,sericin is a useful natural protein.In this paper,viscose anion-exchange fibers have been used to absorb sericin from waste water.The amount of adsorbed sericin into the viscose anion-exchange fibers at different temperatures and times has been studied.The study show ...     

对绢纺重油原料高效除油保胶的探讨

采用 EA-881除油精练剂,以 NaOH 调节练前 pH 值高达11.5,一浴法20 min 可完成绢纺重油原料(重油汰头)的精练。含油率从30%左右下降到0.5%以下,残胶率保持在3%左右,比传统工艺大大节约时间和人力。该剂含有保护剂,在强碱条件下也能保护丝素不受损伤。本文对试验的工艺条件作了探讨。     

钙盐处理对柞蚕丝与桑蚕丝结构和性能的影响

钙盐处理是蚕丝纤维改性的一种重要方法.研究了桑蚕丝与柞蚕丝经氯化钙溶液处理后的溶失行为、形态结构、化学组成和结晶结构的变化.在相同处理条件下,柞蚕丝的溶失率比桑蚕丝小;两种蚕丝断裂强度的下降幅度一致;但柞蚕丝的断裂伸长增加,而桑蚕丝降低.经过钙盐处理,两种丝素的构象都会由β折叠向α螺旋或无规卷曲转变,但这种转变对桑蚕丝更为明显.钙盐处理30min后,柞蚕丝的结晶度上升,而桑蚕丝的结晶度下降.扫描电镜观察显示两种蚕丝均发生了分纤行为,但柞蚕丝变化不如桑蚕丝明显,内部孔洞也没有桑蚕丝多.     

Liquid crystalline spinning of spider silk

Spider silk has outstanding mechanical properties despite being spun at close to ambient temperatures and pressures using water as the solvent. The spider achieves this feat of benign fibre processing by judiciously controlling the folding and crystallization of the main protein constituents, and by adding auxiliary compounds, to create a composite material of defined hierarchical structure. Because the 'spinning dope' (the material from which silk is spun) is liquid crystalline, spiders can draw it during extrusion into a hardened fibre using minimal forces. This process involves an unusual internal drawdown within the spider's spinneret that is not seen in industrial fibre processing, followed by a conventional external drawdown after the dope has left the spinneret. Successful copying of the spider's internal processing and precise control over protein folding, combined with knowledge of the gene sequences of its spinning dopes, could permit industrial production of silk-based fibres with unique properties under benign conditions.     

成丝的速度与方式和蜘蛛丝力学性能的关系

为了分析蜘蛛丝的力学性能和成丝条件间的关系,研究了不同速度下人工卷取的蜘蛛牵引丝以及蜘蛛垂直下落时分泌的牵引丝的力学性能.研究结果表明,随着卷取速度的增大,蜘蛛丝的断裂强度有一极大值,在高速卷取时强度的变化较低速时平缓.垂直下落时蜘蛛分泌的牵引丝的综合力学性能优异,但断裂强度不一定大于人工卷取的丝.成丝速度和成丝方式都对蜘蛛丝的性能有很大影响.     

稀土固着丝胶增重真丝纤维的结构变化

用稀土金属离子通过形成配位结合来固着丝胶，制备了不同增重率的丝纤维，研究了增重丝纤维结构变化。与未增重丝纤维相比，增重丝纤维的纵向形态和截面形态发生了变化，增重丝纤维中氮元素和碳元素的含量呈下降趋势，增重丝纤维中极性氨基酸含量增加，增重丝纤维的结晶度随着增重率的增加而下降，增重丝纤维热分解峰顶温度变化不明显。     

钽喷丝头表面改性技术的研究

喷丝头是化学纤维纺织机上的关键部件。钽喷丝头经过表面改性技术处理后，具有高的硬度和抗蚀性能，将其应用于实际化学纤维的纺丝中取得了好的生产效果，可替代铂金喷丝头。     

残余应力对表面纳米化316L不锈钢疲劳性能影响

超声喷丸处理工艺在316L不锈钢表面制备出了纳米表面晶层,对表面纳米化后和未表面纳米化的316L不锈钢试样进行拉拉低周疲劳试验,然后对试件进行表面残余应力进行测试,并对表面纳米化后材料疲劳性能的影响机理进行了初步分析探讨.研究结果表明,超声喷丸表面纳米化处理可以有效使材料在表面产生残余压应力,并使得表面晶粒细化,从而有效抑制疲劳裂缝萌生,提高材料疲劳寿命.     

甲基丙烯酸羟乙酯接枝改性真丝织物的研究

本文以甲基丙烯酸羟乙酯（HEMA）为单体，过硫酸钾为引发剂．对真丝织物进行接枝改性处理。探讨了不同处理条件对接枝效果及其真丝织物性能的影响。研究表明．选用合适的工艺参数对蚕丝织物进行接枝处理，在保持真丝绸原有风格的同时．可获得较好的改性效果。     

关于脆弱生丝织造性能的研究

将正常生丝、脆弱生丝、经柔软剂处理的脆弱生丝一起作为经丝上机织造,比较它们织造过程中断头、张力情况,并对织物的拉伸性能、染色性能作对比分析,结果表明:脆弱生丝经柔软处理后断头次数明显减少,织物强力有所增加,但与正常生丝一起染色存在色差.     

对GB5889-86苎麻残胶率测试方法的修正意见

本文根据对苎麻碱煮过程中胶质转移动态属性的分析,讨论了GB5889-86试验方法在测定高残胶率精干麻时所存在的主要问题,探讨了多级碱煮测定的设想,通过分析和实验,对GB5889-86试验方法提出了修正意见,并给出了修正值,使之能够适用于高残胶率精干麻的测定,减少了系统误差,提高了测定精度。     

Study on Properties of Jute Fibres Spun on Ring Spinning System

Jute fibre properties,viz. linear density,mechanical properties,and fibre staple length were analyzed in this paper. Morphology,lignin content,and composition analysis for jute fibres were investigated in order to give further understanding of the fibre properties changing during the chemical treatment and yarn producing processes. The results show that jute properties are greatly changed during the processes of chemical treatment,breaking carding,and finisher carding,whereas slight changes can be found in ...     

玉米须中总黄酮的提取及含量测定

本文以玉米须为原料,并以75%的乙醇为提取剂,分别采用常规提取法,超声提取法和微波提取法对玉米须中所含的黄酮类化合物进行提取,利用HCl-Zn粉氧化还原显色反应和铝盐络合显色反应,鉴定了黄酮的存在,以芦丁为标准品绘制标准曲线,回归成线性方程,试样最大吸光波长为510 nm,在此波长下,利用分光光度计,采用NaNO2-AlCl3比色法进行比色,测定玉米须中总黄酮的含量,测得常规、超声、微波三种提取方法的黄酮得率分别为1.781%、1.738%、1.775%,并对各工艺方法进行分析,确定在不同要求下,黄酮的最佳提取工艺条件,为黄酮的工业化提取提供一定的理论依据.     

Chemical Modification of Silk Fibers with Ethylene Glycol Dimethacrylate

Silk fibers have been grafted with ethylene glycol dimethacrylate (EGDMA) and characteristics of the grafted silk fibers were analyzed in relation to the graft yield on the basis of the tensile properties, dyeing behaviour, durability during laundering and solubility of the specimen in NaOH solution. The amount of the acid dye absorbed by the fibers decreased with increasing graft yield, while the value of rating for washing fastness on silk fibers was almost unchanged by the graft treatment The breaking loads of the fiber were almost unchanged whereas rigidity of the fibers increased after graft treatment. Graft treatment enhanced silk fiber durability during laundering and in NaOH solution.     

玉米须不同发育时期物质含量变化研究

以玉米须为原料,研究了玉米须的不同发育时期、不同温度逆境下、不同浓度浸液中抗逆物质、抗氧化物质、营养物质的变化规律,结果表明：嫩玉米须SOD活性最强,老玉米须黄酮、总糖、脯氨酸含量最高;低温嫩须维生素C含量最高,高温熟须蛋白质、糖类含量高;玉米须水浸液SOD活性以0．5g／100mL浓度时、黄酮以3．5g／100mL浓度时为最佳。     

Solid-state NMR determination of the secondary structure of Samia cynthia ricini silk

Silks are fibrous proteins that form heterogeneous, semi-crystalline solids. Silk proteins have a variety of physical properties reflecting their range of functions. Spider dragline silk, for example, has high tensile strength and elasticity, whereas other silks are better suited to making housing, egg sacs or the capture spiral of spiders' webs. The differing physical properties arise from variation in the protein's primary and secondary structure, and their packing in the solid phase. The high mechanical performance of spider dragline silk, for example, is probably due to a beta-sheet conformation of poly-alanine domains, embedded as small crystallites within the fibre. Only limited structural information can be obtained from diffraction of silks, so further characterization requires spectroscopic studies such as NMR. However, the classical approach to NMR structure determination fails because the high molecular weight, repetitive primary structure and structural heterogeneity of solid silk means that signals from individual amino-acid residues cannot be resolved. Here we adapt a recently developed solid-state NMR technique to determine torsion angle pairs (phi, psi) in the protein backbone, and we study the distribution of conformations in silk from the Eri silkworm, Samia cynthia ricini. Although the most probable conformation in native fibres is an anti-parallel beta-sheet, film produced from liquid directly extracted from the silk glands appears to be primarily alpha-helical.     

几种废啤酒酵母细胞破壁方法的比较

以废啤酒酵母为原料,根据实验室条件及试验要求,采用研磨法、冻融法、微波法、超声波法破碎废啤酒酵母细胞壁。利用紫外分光光度计测定上清液中可溶性蛋白质的含量为标准,来评价不同破壁方法对细胞内含物的释放程度。为进一步探索经济、高效的废啤酒酵母的破壁方法提供理论依据。结果表明,废啤酒酵母细胞破壁效果为超声波法﹥微波法﹥冻融法﹥研磨法。     

增材-微锻造加工工艺应力场数值模拟研究

激光熔丝增材制造过程中,材料快热快冷的特点使熔覆层产生不利于表面强度的残余应力,而增材-微锻加工工艺可提高增材制件的加工质量,改善增材制件微观组织及力学性能缺陷.以TC4为研究对象,通过超声微锻造工具头与熔池保持一定的相对距离做进给运动,对材料表面进行高频次冲击与滚压,使熔覆层表面得到改善和强化.对增材-微锻加工工艺进行顺序热结构耦合数值模拟研究,分析加工过程中熔覆层应力场变化情况.研究表明:对尚未冷却的增材熔覆层表面进行超声微锻造,熔覆层由于热源加载产生的残余拉应力转化为较为有益的残余压应力,降低了熔覆层表层缺陷发生的概率.不同的超声振幅、进给速度以及锻造温度参数对残余压应力及法向变形量有较大影响.