经编防刺织物的结构与性能

针对目前国内外对经编防刺针织物研究较少的情况,从织物防刺机制角度分析经编针织物的防刺可行性.测试了经编针织物和机织物的防刺性能,并对实验结果进行分析,得出经编针织物的结构参数如延展线的长度、织物密度,刺入面和刀具刺入角度等与防刺性能之间的关系.在此基础上,对经编针织物和机织物的防刺性能进行了对比.结果表明,在穿刺力和纱...     

基于锚节点等边三角形分布的质心定位算法研究

针对正六边形网格定位算法定位误差不均匀和正方形网格定位算法冗余节点过多等问题,提出了一种新的基于锚节点等边三角形分布的质心定位算法.该算法运用网格划分理论,验证这种网格划分的合理性;通过实验,探索各项参数对于这种新算法的影响.仿真结果表明,该算法在结构简单、硬件投入和功耗相对较少的情况下,提高了节点定位的精确度.但该算法在锚节点数量和计算量上都有所增加,有待下一步改进.     

保鲜纸盒包装——多功能包装系统

<正> 两片式纸盒容器设计 加拿大Dover Industries公司包装部设计生产的两片式纸盒容器包装,是由一个已印刷、不渗透的纸板作为容器底部,配以一个用纸板、热成型或注塑生产的盒盖组合而成。容器的正方形或长方形状及可再封的盖设计,为包装排列、堆垛、贮存和零售等各方面提供了一个比圆形容器更经济的包装。此外,4个印刷表面和盖面,均为印刷宣传语句、产品说明和公司标志等信息传递,提供了较大的产品推广面积。 综合而言,这种两片式的结构、高     

中华人民共和国机械行业标准型材切割机(JB/T报批稿)

<正>1范围本标准规定了型材切割机的基本参数、型式、技术要求、试验方法、检验规则等要求。本标准适用于一般环境条件下,用纤维增强树脂簿片砂轮对圆形钢管、异型钢管、铸铁管、圆钢、角钢、槽钢、扁钢等型材进行切割,并以三相工频、单相电容式或单相串励电动机为动力的可移式型材切割机(以下简称切割机)。     

“超级卫士”的前世今生(上)

<正>一副镜片,就是两块圆形树脂片,这是众多消费者心中真实的答案。一副镜片,除了零售价格有点差异化,其实也没什么大不了的,这是不少零售商的惯性思维。拉倒吧,如果这事儿就只有这么简单,那咱们也就不用这么费劲地挖空心思搞公司、建工厂、招聘技术研发人员,更没有现在吃香喝辣的视光培训师,镜片公司高薪挖来的产品培训、售后服务人员也就只能自娱自乐。一副常规的镜片,到底有多少工序?运用了哪些工艺?花费了多少人力、物力?如果一副要想镜片达到某些特殊的效果,研发人员又需要干哪些具体的工作?今天我们就以上海舒曼光学的     

Untersuchungen über den Einfluß von Rohdichte,Bindemittelaufwand und Spänebeschaffenhei auf das Sorptionsverhalten und die Dickenquellung von Holzspanplatten

Sorptional behaviour and thickness swelling were determined for particleboards of different densities (0.5 g/cm³, 0.8 and 1.05 g/cm³), different resin levels, and different flake dimensions. The results led to the following conclusions: An increase in board density and/or resin (ureaformaldehyde) level decreases the equilibrium moisture content of particleboards at high relative humidity by about 1% moisture content; by contrast, flake dimensions seem to have no pronounced influence on the sorptional behaviour of particleboards. Under equilibrium conditions the thickness swelling of particlchoard in humid air increases significantly with increasing board density, by contrast, thickness swelling becomes lower as resin level increases. The use of fine flakes instead of coarse flakes decreases thickness swelling insignificantly. As regards thickness swelling in water, increasing resin level led to a decrease in thickness swelling, whereas no consistent relationship was found between board density and thickness swelling after 2h and 24h soaking in water. Accordingly, it has again been proved that no definite correlations exist between thickness swelling in water and in humid air.     

改性芳纶与环氧树脂复合体的制备及其防刺性能

为提升芳纶织物的防穿刺效果,采用氧等离子体表面处理技术改性的芳纶1414织物与环氧树脂复合制备环氧芳纶复合体。分析了等离子体处理对织物功能改性的影响,研究了环氧树脂涂覆织物后复合体的防刺性能。结果表明:采用氧等离子体处理,在处理功率为600 W、处理18 min时,织物表面纤维刻蚀明显,含氧基团增多,润湿性提高,但织物拉伸强度有所下降;当环氧树脂涂覆在等离子体改性后的芳纶织物上,树脂中环氧基团与芳纶中含氧活性基团键合牢固,复合体黏结强度较好,拉伸强度较未经处理的芳纶织物增加了7.89%,复合体防穿刺效果较普通芳纶1414织物提升显著,且多层组合结构的防刺效果更优异。     

人造金刚石填充聚酰亚胺树脂基复合材料防刺性能

为研究树脂材料的防刺性能及防刺机制,利用手糊成型与热压法成型制备了手糊分层结构和均布结构层2种结构的人造金刚石填充聚酰亚胺树脂基复合树脂片,并探讨了人造金刚石粒径、填充体积分数对树脂片防刺性能的影响。研究结果表明:经过人造金刚石填充的聚酰亚胺树脂片的防刺性能得到提高,并且均布结构层分层复合结构的树脂片的防刺性能更好;随着人造金刚石粒径的减小,树脂片防刺性能出现先减小后增加的趋势,故防刺机制基本在于碰撞概率与树脂基的防挡;比较防刺力和消耗功发现,不同填充体积分数的单层防刺树脂片的防刺性能随人造金刚石填充体积分数的增加而逐渐降低,该趋势的成因在于复合树脂片的脆化与破坏;在颗粒等效粒径为300 μm、体积分数为10%时,其防刺性能最好。     

组织结构对UHMWPE短纤纱织物防刺性能的影响

UHMWPE短纤纱具有优秀的抗切割性与较好的树脂浸润性,非常适用于制作防刺材料。文章试织了12种不同织物规格的试样,进行准静态穿刺实验,探究5种因素(组织、紧度、纱线线密度、经纬密和面密度)对织物防刺性能的影响,并比较不同穿刺角度下织物防刺性能的差异。结果表明:与方平织物与接结双层织物相比,平纹织物的防刺性能最好;同种经纬密或同紧度下,粗特纱织制的平纹织物防刺性能好;随着经密增加,紧度增加,面密度增加,防刺性能逐渐增加,但织物过于紧密时,防刺性能反而降低;平纹织物的穿刺性能具有各向异性,经纬向的防刺性能优于45°方向。     

切丝宽度对细支烟卷制质量、主流烟气及感官质量的影响

在其他制丝工序加工参数和卷制参数相同的条件下,分别按0.6,0.7,0.8,0.9,1.0 mm切丝宽度制丝并卷制细支烟,探索切丝宽度对细支烟烟丝结构、卷制质量、烟气成分及感官质量的影响。结果表明:①切丝宽度为0.6~1.0 mm时,整丝率与切丝宽度显著正相关,碎丝率与切丝宽度显著负相关。②吸阻、总通风率、焦油量与切丝宽度间均呈显著负相关关系。切丝宽度为0.6~0.8 mm时,细支烟单支重、吸阻、硬度、总通风率及焦油量与设计值的相对残差较接近于0。③随切丝宽度降低,细支烟感官质量整体表现逐渐向好。综合不同切丝宽度细支烟卷制质量、烟气成分和感官质量,兼顾烟丝结构,细支烟适宜切丝宽度为0.7~0.8 mm。     

Acetylated,isocyanate-bonded flakeboards after accelerated aging

To improve flakeboard dimensional stability and mechanical properties for long-term exterior exposure, we fabricated and tested a highly durable isocyanate-bonded acetylated flakeboard. Flakeboards were tested for internal bond strength, thickness swell, modulus of elasticity, modulus of rupture, and breaking strength in bending, after two severe accelerated aging tests. Flake design, flakeboard density, resin content, and their interactions were critical to the performance of acetylated flakeboards in the aging tests. In bending tests, the longer disc-cut flakes produced much higher strength values than did the ring-cut flakes. In internal bond strength tests, the ring-cut flakes performed comparably to the disc-cut flakes. However, ring-cut flakes contributed somewhat more to reducing thickness swell than did disc-cut flakes. Acetylated flakeboards fabricated at high density were much stronger than those fabricated at low density. However, the high-density boards developed more thickness swell than did the low-density boards. The 5-% resin content contributed little to increased strength values in the bending tests, but this level of resin significantly improved flakeboard performance internal bond strength and thickness swell tests. Acetylation did not interfere to any practical degree with the isocyanate resin, and all property values were enhanced by acetylation, particularly internal bond strength and resistance to thickness swell.     

芳纶/不锈钢长丝包芯纱织物的制备及其防刺性能

为开发低成本的柔性可穿戴防刺材料,选用线密度为48.2tex的高性能芳纶1414短纤纱线和直径为0.06 mm的304不锈钢长丝,采用包芯纱工艺纺制芳纶/不锈钢长丝包芯、纱,优化纺纱工艺参数,得出最佳纱线包绕数,并用该纱线制备出具有防刺性能的织物。对纱线的力学性能和织物防刺性能进行测试,改变织物叠层数,探讨叠层数对织物防刺性能的影响。研究结果表明:当纱线的包缠捻度为200捻/m左右时,纱线的断裂强度为77.99 c N/tex,有害毛羽指数为90.42,可满足后续织物的织造;平纹织物的刀刺和锥刺性能与织物叠层数呈正相关线性关系。锥刺和刀刺的刺入原理不同,锥刺的破环机制是纱线滑移,刀刺的破坏机制是纱线切割断裂。     

Effects of Flake Size on Textural and Cooking Properties of Restructured Beef and Pork Steaks

Flaked and formed beef and pork steaks were manufactured using eleven different Comitrol cutting heads selected to give a wide range in flake size. Data from texture profile panel, Instron and cooking studies were collected. As flake size increased, visually detected fi-brousness, first bite hardness, cohesiveness of the chewed mass, number of chews required for swallowing, amount of connective tissue detected by sensory panel and shear force all increased, while uniformity of the chewed mass decreased. Textural properties in beef and pork steaks were affected in a similar manner by flake size. Thickness of the flake particle was as important as width of the flake particle in affecting texture.     

Uptake of Tritiated Liquids by Individual Breakfast Cereal Flakes

ABSTRACT: Surface liquid adhesion (SLA) and liquid absorption (LA) of tritiated liquids, including water and skim, low-fat, whole, and fat-enriched milks, by cornflakes (CF) and frosted flakes (FF) were determined by scintillation counting using water-[³H] at 0.5 μCi/mL. SLA or the liquid adhering to individual flakes after a short immersion period was the same for CF and FF in the case of water (approximately 0.011 μL mm⁻² of flake) but were always higher for CF than for FF and increased as the fat content in milks augmented. LA of individual flakes, followed for 300 s of soaking, increased with time and was always higher for CF than for FF (for the same liquid), however, data did not follow a regular pattern. Flakes showed quite compact outer surfaces and an internal porous matrix composed of air cells of various sizes separated by dense walls of different thicknesses. This heterogeneous microstructure of individual flakes may be the cause of the lack of a simple kinetics during the soaking process. Previous results obtained by soaking a mass of flakes overestimated the uptake of fluid by individual because they included the liquid occluded between the flakes.     

烟片皱缩率测定方法的建立及差异性分析

[目的]准确测定烟片的烤后皱缩率,评价不同烟叶原料的皱缩特性.[方法]建立一种基于干燥前后面积变化率的烟片皱缩率测定方法,通过正交试验对烟片尺寸、形状和干燥温度等测定条件进行优化,利用所建立的方法测定33种初烤后烟叶的皱缩率并进行差异性研究.[结果](1)烟片干燥后既会产生皱缩、也会发生弯曲,利用网孔盖板可有效控制弯曲...