喷孔结构对FDY型吸丝枪流场影响的数值模拟分析

使用软件CFX 12.1对具有不同喷孔结构的吸丝枪内部流场进行模拟,分析了流场分布与吸丝性能之间的关系,阐明喷孔结构对吸丝枪性能的影响机制,得到合理的结构参数:喷孔数N为3,孔径d为2.0 mm,喷孔角度为75°。结果表明:增加喷孔数减少了喷出气流的自由扩散,增强其方向性,提高枪内管壁附近空气密度和空气周向速度分量,从而提高吸丝力;过大的喷孔数增加了喷出气流间的冲突,减小了吸丝力;合理的孔径有利于强烈涡流的形成,并避免正激波的产生,提高了吸丝力;喷孔角度主要控制空气周向速度分量的大小,引起涡流强度变化,从而改变吸丝力;吸丝效率和气流分布密切相关,尤其是空气周向速度分量影响最大;正激波的产生不利于吸丝力的提高,应尽量避免。     

拉瓦尔管结构对FDY型吸丝枪性能的影响

为阐明拉瓦尔管结构对FDY型吸丝枪性能的影响,对吸丝枪流场特征进行理论分析,确定其喉部直径与喉部长度。通过改变拉瓦尔管收缩角和扩大角,测定吸丝枪的吸丝张力和压缩空气质量流率,分析收缩角α和扩大角β对吸丝枪吸丝效率的影响,得到合理的拉瓦尔管结构参数:收缩角α为90°,扩大角β为6°。结果表明:合理的收缩角有利于气流加速,并顺利形成较强的涡流,从而提高吸丝效率;合理的扩大角有利于加速拉瓦尔管扩大部位的超音速涡流,减少气流与纱线运行阻力,提高吸丝效率,但扩大角过大,会导致正激波过早出现,气流加速提前结束,动能损失大,导致吸丝效率下降。     

超高速纺丝吸丝枪吸丝效率影响因素的研究

为了阐明生产条件和纱线规格对吸丝枪吸丝效率的影响,测试了不同纱线种类、纱线喂入速度v和供气压力(表压)p下吸丝枪的吸丝张力F和压缩空气质量流率G,分析了这些因素对吸丝枪吸丝效率η(η=F/G)的影响机理,得到如下结果:p一定时,随着v的增加,F和η减小;v一定时,随着p的增大,F增大,但η下降;相同规格的全牵伸丝(FDY)比拉伸变形丝(DTY)的F和η大;同一种类纱线,线密度越大,F和η越大。研究表明:不同的产品品种和生产条件,应该合理选择吸丝枪并选用合适的供气压力,从而提高生产效率,降低能耗。     

拉瓦尔管结构对涤纶全拉伸丝吸丝枪流场的影响

为给提高吸丝枪性能提供技术支持,使用CFX 12.1软件对具有不同拉瓦尔管结构的吸丝枪内部流场进行模拟,分析了流场分布与吸丝性能之间的关系,阐明了拉瓦尔管结构对吸丝枪性能的影响机制。模拟结果和实验结果相吻合,合理的拉瓦尔参数为收缩角α= 90° 和扩大角β= 6°。合理的收缩角有利于气流在拉瓦尔管中平稳加速,减少返流与乱流,并避免产生强烈的正激波,减少动能损失,从而提高吸丝效率;合理的扩大角能使吸丝枪内气流速度周向分量和高速高密气流区域长度适中,增加空气对纱线的拖曳力,减小管壁对纱线的摩擦力,降低正激波产生的动能损失,提高吸丝效率。     

关于聚酯工业丝网络度的研究

本文研究了网络喷嘴形式、压缩空气压力、压缩空气进网络喷嘴管的管径及卷绕张力对不同规格的聚酯工业丝网络度的影响     

自动上丝机构的研发

为解决采用吸枪进行手动上丝方式中存在受工作环境及设备内部结构的影响较大,上丝过程比较繁琐,劳动强度大,上丝效率低等问题,研发出一种自动上丝机构,该机构由减速电机、链轮、链条、导丝环等组成。详细介绍了该自动上丝机构的结构及操作步骤,并对其特点和应用进行了分析。指出这种自动上丝机构结构简单,劳动强度低,上丝效率高,不受环境影响,应用场合广泛;在实际使用过程中,能够很好地满足使用要求。     

防静电织物相关服用性能的测试分析

研究嵌织导电丝类防静电织物的服用舒适性和外观性能.测试了4种防静电织物的表面电荷密度、透湿量、芯吸高度、透气率、折皱回复角、抗起毛起球性和悬垂系数,并运用织物结构理论分析了导电丝对嵌织导电丝类防静电织物相关服用性能的影响.研究表明:导电丝含量的增加大大降低了织物的透湿性;导电丝的分布状况对织物的芯吸能力有明显影响;但导电丝的配置有利于增强织物的折皱回复性能.通过对主体原料的合理选择及织物结构的合理设计,在不增加导电丝含量的前提下可以使织物既具有优良的防静电性能又能获得较好的服用性能.     

喷气涡流纺喷嘴喷孔参数的分析

喷气涡流纺是利用喷嘴内高速气流的旋转对纤维加捻成纱的设备,为了分析喷嘴的结构参数对成纱质量的影响,选择喷嘴的喷孔直径d为0.5 mm,分别在不同喷孔数量n(5,6)及不同喷孔角度θ(60°,65°,70°,75°,80°)下,在新型涡流纺纱机上对粘胶原料进行纺纱实验。实验结果得到了喷孔最优结构参数:喷孔孔径×数量φ0.5×5;喷孔角度70°。     

转盘振动喂丝机吸丝口的改进

风力送丝系统中的转盘振动喂丝机在运行过程中,转盘中的烟丝受振动易发生烟丝分层,导致卷烟机落料器吸入烟丝结构差别大、吸丝时间长、卷烟质量不稳定等问题,为此,对转盘振动喂丝机的吸丝口进行了改进.改进措施为:①采用浮动式吸丝口替换喂丝机的固定式吸丝口;②拆除振动系统的减速电机,取消转盘的振动功能.改进后有效解决了转盘振动喂丝机的烟丝分层问题,卷烟机落料器内烟丝碎丝率变异系数降低了0.23,吸丝时间减少了13 s;烟支端部落丝量降低2.41 mg/支,吸阻标准偏差降低51.2 Pa,烟支重量标准偏差降低5.5 mg/支.实际测试结果表明,风送到卷烟机落料器内的烟丝结构更加均匀,提高了烟支卷制质量的稳定性.     

涤纶牵伸网络丝生产技术新探

丝在冷盘上绕第三圈时经过网络喷嘴,最后在冷盘上绕第四圈,使高频气流对丝产生的弦振动不影响卷绕成型,使钢领板换向造成的张力波动不影响网络成型,提高了网络均匀度和满卷率,消除了松圈丝。     

蛋白质水解度测定方法综述

对目前国内外常用的蛋白质水解度测定方法进行了综述，其中pH—state方法是通过滴定水解过程中释放的质子测定DH；OPA、TNBS及国内常用的水合茚三酮和甲醛等测定方法是利用游离氨基的反应测定DH。     

SEROLOGIC IDENTIFICATION OF SPECIES OF ORIGIN OF SAUSAGE MEATS

SUMMARY: A partially purified immunoglobulin G (lgG) solution prepared from the serum of species to be tested was heated to the specifications for sausages. The resulting supernatant fluid was decanted and the precipitate washed with saline and used to immunize rabbits. The supernatant fluid was used to sensitize tanned sheep red blood cells. The immune serum was rendered monospecific by absorptions with heterologous, heated lgG precipitates. A sample of monospecific immune serum was absorbed with a washed homogenate of sausage. Aliquots of the monospecific immune serum, both untreated and sausage absorbed, were tested with cells sensitized with the homologous heated lgG supematant fluid. A significant reduction of titer by sausage absorption indicated that the sausages contained the meat homologous to the immune serum.     

BASIS OF STABILITY OF AMINE SALTS OF LINOLEIC ACID

SUMMARY— The mechanism and generality of the known stabilization against autoxidation conferred on linoleic acid by certain basic amino acids, such as lysine and arginine, was investigated. Basic amino acids were the only class of compounds found to confer the effect. However, the smallest basic amino acid, 2,3-diaminopropionic acid, was not effective, nor was αβω-diaminc acid, 3,6-diaminohexanoic acid, although a simple isomer of lysine. The stabilization was observed only in the solid phase. Inclusion of sodium chloride in the solid matrix was deleterious to the effect. A large number of physical and chemical observations were made and correlated but it has not been possible to draw detailed conclusions about the mechanism of stabilization, nor can a detailed structure of the stabilized complex be suggested. The cause of the phenomenon appears to be closely associated with the physical arrangement of the ions in the crystal lattice.     

百年风尚

一场流光溢彩、赏心悦目的展览,一段百年风尚演进的传奇旅程,一次东西方文化艺术的完美对话。2013年9月13日,“博萃臻艺一中西方珍宝艺术展”在辽宁省博物馆举行了隆重的开幕仪式,法兰西共和国驻华大使白林女士、辽宁省文物局局长丁辉先生、辽宁省博物馆馆长马宝杰先生、卡地亚全球总裁兼首席执行官邓阁仕先生、卡地亚区域行政总裁（北亚洲）陆慧全先生、卡地亚中国区首席执行官陆意斯先生、辽宁省文物店总经理张春鹰先生,以及众多文化界与文博界的贵宾齐聚一堂,共同见证了这场文化艺术盛事。     

聚多元羧酸盐的合成及应用

研究了聚多元羧酸盐的合成方法及反应机理,将其应用于洗涤剂和PVC制品中分别代替三聚磷酸钠和邻苯二甲酸二丁酯,证明有良好效果。     

EFFECTS OF TYPES OF FAT AND OF RATES AND TEMPERATURES OF COMMINUTION ON DISPERSION OF LIPIDS IN FRANKFURTERS

ABSTRACT— The effect of time, temperature and rpm of comminution of emulsions was determined on the dispersion of approximately 25% of beef fat, pork fat or cottonseed oil in frankfurters. The numbers of lipid particles 5 μ or less in diameter increased in frankfurters containing either beef or pork fat as comminution was continued to higher temperatures, with pork fat dispersed more thoroughly. Fat tended to separate from frankfurters containing beef fat in particles 200 μ or more in diameter. In contrast, no specific degree of dispersion of particles 5 μ or less in diameter consistently indicated emulsion stability, or its lack. Increased rpm during comminution produced an increased dispersion of beef or pork fat. Under the same conditions pork fat was dispersed more finely than beef fat. Dispersion of cottonseed oil produced finely dispersed particles beyond the resolution of light microscopy, as was confirmed by electron microscopy which showed a substantial number of particles to be less than 1 μ in diameter.     

DEVELOPMENT OF CHAINS OF CELLS OF SACCHAROMYCES CEREVISIAE DURING FERMENTATION

The lengths of chains of cells of Saccharomyces cerevisiae were studied during fermentation. Pitching yeast generally contained about half of the total number of cells as two-celled chains. The chain lengths varied during the subsequent fermentation and the variations were characteristic of the strain. Electronic counting assessments of chain length were unreliable.     

STABILITY OF AQUEOUS EMULSIONS OF THE ESSENTIAL OIL OF HOPS

Hop oil emulsions prepared from different varieties of hops have been found to exhibit enhanced physical stability on the addition of blends of the emulsifiers Span 20/Tween 80 or Span 60/Tween 60. Examination of the particle size and volume distributions of an emulsion by use of a Coulter Counter was found to be an excellent method of monitoring its stability. An indication as to the relative efficiency of emulsifiers can be obtained from Coulter Counter measurements on hop oil emulsions after storage for 4 days. The use of an ultracentrifuge provies a rapid means of testing emulsion stability and hence the effectiveness of emulsion stabilizers.     

矩阵乘积的行式,列式

给出了ｍ×ｍ矩阵与ｍ×ｎ矩阵的行（列）式的表达式．若Ａ＝ａ１１ａ１２…ａ１ｍａ２１ａ２２…ａ２ｍ……ａｍ１ａｍ２…ａｍｍＢ＝ｂ１１ｂ１２…ｂ１ｎｂ２１ｂ２２…ｂ２ｎ……ｂｍ１ｂｍ２…ｂｍｎ分别是ｍ×ｍ，ｍ×ｎ矩阵，则｜Ａ｜｜Ｂ｜＝｜ＡＢ｜＋∑ｉ１＜ｉ２＜…＜ｉｔｊ１＜ｊ２＜…＜ｊｔ１≤ｔ≤ｍｎ－ｔ≥ｍＮＢｉ１ｉ２…ｉｔｊ１ｊ２…ｊｔＮＡＢ１…ｍ（－１）ｓｔ＋１ｊｔ＋１…（－１）ｓｎｊｎ其中ｉ１，ｉ２，…，ｉｔ是１，２，…，ｍ中ｔ个数码；ｊ１，ｊ２，…，ｊｔ，ｊｔ＋１，…，ｊｎ是１，２，…，ｎ的一个排列；ｓｒ＝π（ｊ１，ｊ２，…，ｊｔ，ｊｒ）（ｒ＝１，２，…，ｎ）是排列ｊ１，ｊ２，…，ｊｔ，ｊｒ的反序数．     

ANALYTICAL CHARACTERIZATION OF THE PRODUCTS OF NONENZYMATIC GLYCOSYLATION OF LYSOZYME

The quantitative analysis of the reaction products of the water activity dependent nonenzymatic glycosylation of lysozyme was not straightforward. Difficulties arose in the determination of the number of bound glucose molecules because glycosylation leads to glucose mediated protein aggregation, and the likely presence of a mixture of relatively labile Schiff-base intermediates, and the more stable ketoamine products generated by Amadori rearrangement. Polyacrylamide gel electrophoresis was used to monitor protein aggregation; periodate oxidation, nuclear magnetic resonance (NMR), and oxalic acid hydrolysis combined with HPLC, emerged as the most promising methods to quantitate the degree of glycosylation. Possible interpretations are advanced to explain the apparent discrepancies in degree of glycosylation suggested by the different analytical methods evaluated.