滚筒摩擦机参数对服装带电电荷量测试的影响

探讨滚筒摩擦机技术参数对服装带电电荷量测试结果的影响。通过分析新旧标准滚筒摩擦机的滚筒尺寸、滚筒转速、滚筒内温度及标准摩擦布等对服装防静电性能的影响,最终得出:采用新标准的滚筒摩擦机测试服装带电电荷量的数据较旧标准普遍偏大,其技术参数的改变对测试结果有一定的影响。认为:标准摩擦布材质对服装带电电荷量的测试结果影响最为显著,不能简单地以旧标准来衡量产品的防静电性能。     

防静电服及其检测标准浅析

防静电服可防止服装上的静电积聚,从而达到防止事故产生的目的。GB12014—2009《防静电服》参考了国外标准,并结合我国实际生产和应用国情在旧标准的基础上对防静电服的技术要求作了较大的修改和补充。本文对GB12014新旧标准的不同点及与国外标准的差异进行了粗略的解析,并就应用过程中出现的问题提出建议,旨在对GB12014—2009《防静电服》有更深入的了解。     

影响防静电服电荷量因素分析

为探究影响防静电服电荷量的因素,随机选取10套防静电服作为试样,先将10组试样分别放入60℃和常温的测试桶内,以测试试样在不同温度测试桶内测得的电荷量值,再将10组试样分别放入包覆聚丙烯腈标准摩擦布和包覆锦纶标准摩擦布的测试桶内,以测试试样在包覆不同标准摩擦布测试桶内测得的电荷量值.该试验结果表明,试样在60℃测试桶内...     

新型防静电A级面料

根据国家标准GB 12014-2009防静电服要求,A级防静电面料点对点电阻为1×105~107Ω。根据对点对点电阻测试原理,设计了新型的组织结构的防静电面料,并提供了相应的产品规格。     

GB 12014—2019《防护服装防静电服》的解析

解析GB 12014—2019《防护服装防静电服》标准。将该新标准与GB 12014—2009和GB/T23464—2009的差异进行了对比和分析,列出了其中涉及技术要求的改变之处。指出:新标准进一步提高了质量控制水平,强化了标准的合理性和先进性。认为:选用导电缝纫线可以确保服装整体的静电导通。     

试样选取和投样方式对防静电服带电电荷量检测结果的影响

在带电电荷量检测中,现行标准GB 12014—2009附录B的方法中,试样的选取和投样方式存在一定的差异性,因此本文针对不同的试样选取和投样方式下,对带电电荷量测试的结果进行了分析与研究。结果表明,在其他条件满足标准时,试样的选取和投样方式对带电电荷量的影响较大,且同一套防静电服的上衣的带电电荷量大于裤子的带电电荷量,自动投样方式测试的带电电荷量结果重现性好,且大于手动投样方式测试的带电电荷量,但是该装置也存在一定的缺陷,需进一步完善,并相应地提出了解决方法和建议。     

导电纤维置入方式对织物防静电性能的影响

研究了导电纤维在织物中的置入方式对织物防静电性能的影响。通过选择不同的导电纤维、置入方式及防静电标准,测试并分析织物的防静电性能。结果表明:炭黑型导电长丝以经向、经纬向方式交织的织物均可以达到GB 12014—2009标准的要求;导电短纤混纺、炭黑型导电长丝经向镶嵌纬向交织的织物符合EN 1149-5:2008标准的要求。结论认为:可根据不同的防静电标准要求选择导电纤维的置入方式,以满足产品的防静电性能要求。     

浅析GB 12014—2009中点对点电阻要求及测试方法

围绕防静电服标准GB 12014—2009中点对点电阻的技术要求及测试方法,主要从标准技术要求的术语、测试方法中的试样、样品的放置方式、选取的测试点、电极组距离、绝缘台面等的差异性几个方面,对点对点电阻最终测试结果的影响进行了详细分析,为该标准修订提供相应的参考。     

解读防护服装防静电服新旧标准

文章对产品标准GB 12014《防护服装防静电服》2019版和2009版进行对比解读,分析指出了二者异同,为生产企业和检测机构提供技术参考,对新标准推广和准确实施提供积极参考。     

对国标GB12014-1989《防静电工作服》存在问题的研究及解决方案

GB12014-1989标准自1990年实施以来,历时18年一直未予修订.此期间防静电工作服产品有很大的发展,新材料、新工艺、新品种层出不穷.在导电纤维方面,浸透铜离子导电纤维工艺早已被淘汰,碳素导电纤维截面也在不断变化;在服装方面,除普通的防静电服之外,防静电羊毛衫、防静电西服、防静电针织内衣、防静电羽绒服、防静电无菌服、防静电无尘服等种类繁多的服装,这些工作服除能满足防静电的共同要求外,还能满足不同的物理性能指标的要求.     

Interaction between Emulsion Droplets and Escherichia coli Cells

ABSTRACT Oil‐in‐water emulsions (20% n‐hexadecane, v/v) were stabilized by dodecyltrimethylammonium bromide (DTAB), Tween 20, or sodium dodecyl sulfate (SDS). Particle size distribution and creaming stability were measured before and after adding Escherichia coli cells to emulsions. Both E. coli strains promoted droplet flocculation, coalescence, and creaming in DTAB emulsions, although JM109 cells (surface charge = ‐35 mV) caused faster creaming than E21 cells (surface charge = ‐5 mV). Addition of bacterial cells to SDS emulsions promoted some flocculation and coalescence, but creaming stability was unaffected. Droplet aggregation and accelerated creaming were not observed in emulsions prepared with Tween 20. Surface charges of bacterial cells and emulsion droplets played a key role in emulsion stability.     

石油工业用抗静电过滤布的开发

在对比其它抗静电方法的基础上 ,从石油工业应用方面入手 ,采用涤纶和锦纶交织交并工艺 ,利用两者摩擦带电性能不同、可以实现静电中和的特点 ,设计开发了一种新型的抗静电过滤布。依照标准GB/T 12703—91测定电荷密度 ,对所开发的 21个样品进行了实践检验 ,并通过回归分析的方法 ,采用 2个方程模型对散点分布进行趋势优化 ,得出最优方案。     

低温解冻相对湿度对鸡胸肉品质的影响

研究不同相对湿度（relative humidity,RH）条件下低温（4 ℃）解冻对鸡胸肉品质特性的影响,以RH为65%～81%的冷藏库解冻（4 ℃）为对照组,以4 种不同RH解冻为实验组（4 ℃;RH 80%、85%、90%、95%）,分析不同RH条件下低温解冻对鸡胸肉解冻时间、汁液流失率、pH值、色泽、质构、蛋白溶解度、细菌总数、总挥发性盐基氮（total volatile basic nitrogen,TVB-N）含量及水分分布的影响。结果表明,随着解冻环境RH的提高,解冻时间不断延长,RH 90%和RH 95%低温解冻组鸡胸肉解冻汁液流失率、T23峰面积比显著低于对照组（P＜0.05）,L*值、a*值、硬度、咀嚼性、总蛋白溶解度、肌浆蛋白溶解度、T22峰面积比显著高于对照组（P＜0.05）,RH 95%组细菌总数和TVB-N含量显著高于RH 90%组（P＜0.05）。综合分析,RH 90%低温解冻可有效缓解解冻过程中肌肉蛋白质变性,降低解冻后汁液流失并有一定改善肉色的作用,解冻后鸡胸肉品质最佳。     

聚合物熔体微分静电纺电场对射流的影响及其物理模型

为研究电场强度及接收装置材质对无针静电纺丝射流效率和射流分布均匀性的影响,在提出的熔体微分直线静电纺丝装置上,通过改变纺丝电压和接收装置材质,分析了喷头端最大电场强度和电离电荷对射流效率及均匀性的影响。结果表明:喷头端电场强度越大,射流效率越高,射流分布越均匀;当接收端的局部电压高于喷头端的电压时,电离离子宏观上表现出向喷头端运动,会抑制射流的形成;在高压收集端铺设电阻值为2.7×10⁵ Ω的纸,可以实现电离电荷的二次均匀分布,消除局部离子流引起的射流缺失现象;在接收装置上铺设电阻值大于1.0×10¹¹ Ω的聚对苯二甲酸乙二醇酯(PET)会增加纺丝回流的电阻,导致电荷在PET上聚集,反作用削弱喷头端的电场强度,引起射流效率的降低。     

从电荷分析研究两性淀粉对新闻纸撕裂度的影响

本文从电荷分析研究了两性淀粉对新闻纸撕裂度的影响,研究结果表明：两性淀粉用量对新闻纸浆的电荷密度有影响,新闻纸浆的可溶净电荷、表面阳电荷和CTR随淀粉用量的增加而增加,表面阴电荷随淀粉用量的增加而减小,在淀粉用量较低时,可溶净电荷变化比较缓慢,而纸浆表面电荷CTR的变化非常显著,用量大于0.5%后,可溶净电荷增加较快,而对CTR的影响很小,pH值对添加两性淀粉0.5%的新闻纸浆的可溶净电荷和表面阳电荷的影响不大,表面阴电荷随pH值的增加而减小,在pH值小于6时,变化的幅度较大,pH值大于6,表面阴电荷变化的趋势减小,在pH=6时,CTR达到最大,结合pH值对桉木化机浆与新闻纸浆的影响可以知道：pH=6～8时,整个浆料系统接近电中性,两性淀粉与纤维之间的相互作用达到最佳,从而使纸页的纤维间结合状态最好。     

Interconversions of Isoflavones in Soybeans as Affected by Storage

ABSTRACT: Conversions of isoflavones in soybeans under 4 conditions were investigated. Soybeans were stored in 84% RH, 30 °C for 9 mo and in 57% RH, 20 °C, cold (4 °C), and an uncontrolled ambient garage for 18 mo. Isoflavones were analyzed by HPLC. In 84% RH, 30 °C, the interconversion between aglycones and β-glucosides was significant ( p < 0.001). The percentage of β-glucosides and malonylglucosides in total isoflavones decreased from 99% to 3% in 9 mo. In contrast, the aglycones increased from 1% to 97%. In 57% RH, 20 °C, and ambient conditions, the glucoside forms increased with storage time, but malonylglucosides tend to decrease. In the 4 °C condition, isoflavone distribution had no significant ( p > 0.05) changes during storage.     

造纸湿部电荷的检测技术

随着造纸工业的发展,各类造纸化学品的相继使用,使得造纸湿部的电荷变化日趋复杂,而湿部的电荷分析是应付纸机各种变化的一种有力工具,达到优化和稳定造纸湿部的目的.主要介绍了胶体电荷检测的动电学现象和胶体滴定法,并且对这两种方法的原理、特点和在线电荷的测量以及电荷分析的意义进行了讨论.     

Effect of Relative Humidity on the Oxidative Stability of Microencapsulated Sea Buckthorn Seed Oil

ABSTRACT: The effect of relative humidity (RH) (20 °C: RH 11%, 54%) on oxidative stability microencapsulated sea buckthorn seed oil was studied using bulk oil as a reference. Microcapsules were prepared by spray-drying using maltodextrin-gum arabic (MD/GA) and corn starch sodium octenyl succinate derivate (HiCap) as the wall materials. The influence of the physical state of the wall material was also evaluated. Under dry conditions, the microencapsulated oils were most stable, but the oxidation of the bulk oil was accelerated. At 20 °C and at RH 11%, the peroxide value of the bulk oil exceeded 20 meq/kg within 1 wk. Microencapsulation prolonged the shelf-life of the oil from 1 wk to 2 mo at 20 °C, when the encapsulating matrix was in glassy state. In conditions in which the HiCap matrix was in a rubbery state (RH 54%, 20 °C), the oxidation proceeded very quickly, reaching a peroxide value of 20 meq/kg just after 1 wk. Caking and collapse of the microcapsule powder were observed in the rubbery state. At accelerated conditions (50 °C: RH 11%, 30%, 45%), the oxidation was noticeably fast, not only in the bulk oil but also in the MD/GA matrix, even in the glassy state. The behavior in the HiCap matrix was more complex as the amount of peroxides started to decrease in time. This was assigned to the structural collapse in HiCap microcapsules. The behavior of the microencapsulated oils under accelerated conditions did not correlate with their behavior at 20 °C.     

The effects of temperature and relative humidity on ochratoxin A formation in fresh liquorice root

In this study, the effects of temperature and relative humidity (RH) on ochratoxin A (OTA) formation during liquorice root storage were investigated. For this purpose, a real storage procedure in which fresh root was dried in the open air was simulated. Four RH-temperature combinations corresponding to average climate conditions (RH-temperature) of each season in an important liquorice growing and processing region were simulated as follows: A, autumn (T?=?15°C, RH?=?49%); B, winter (T?=?9°C, RH?=?51%); C, spring (T?=?22°C, RH?=?35%); and D, summer (T?=?29°C, RH?=?27%). The crushed fresh roots were incubated for 60 days, and the OTA content of the roots was determined at 20-day intervals by using inverse ion mobility spectrometry. The results showed that the maximum levels of OTA occurred after 40 days and were 4.3?±?1.1, 0.9?±?0.2, 7.3?±?0.0 and 24.2?±?2.5?ngg^?1 in roots stored under simulated conditions A, B, C and D, respectively. After 40 days, the amount of OTA started to decline in all samples but at different rates. The results seem to indicate that temperature plays a more significant role than RH in producing OTA by moulds in liquorice root. It appears that 22°C could be considered as the critical temperature for OTA formation in liquorice root stored under experimental conditions. It could be concluded that liquorice-processing plants should obtain, dry and store fresh moist root when the temperature is below the critical point. Moreover, the roots stored in the open shade condition should not be covered by plastic films even when it is raining as this increases the root temperature.     

Changes of Selected Physical and Chemical Components in the Development of the Hard-to-Cook Bean Defect

The effects of storage temperature and humidity were monitored on several physical and chemical components of cowpeas and beans. Seeds stored at 29°C, 65% RH required prolonged cooking times; however, seeds stored in other conditions (5°C, 30% RH; 29°C 30% RH; and 5°C, 65% RH) maintained short, stable cooking times throughout storage. As cooking time increased, phytate, phytase activity, amylose solubility, high methoxyl pectin and protein solubility decreased. Solids leached during soaking and low methoxyl pectin increased as cooking time increased. These results were consistent with the proposed theory that the hard-to-cook defect involves interactions between phytate, minerals, and pectin. However, they did not eliminate possible roles of starch and protein solubility.