照相明胶试验方法——苏联国家标准ΓСОТ25183.1-82—ΓСОС25183.10-82

苏联国家标准委员会于1982年正式颁布了苏联国家标准“照相明胶”(试验方法)共包括十项: 1.照相明胶的接受和选样标准; 2.照相明胶中细颗粒含量测定方法; 3.照相明胶溶解时间测定方法; 4.照相明胶粘度和粘度降测定方法; 5.照相明胶透明度测定方法; 6.照相明胶熔化温度测定方法; 7.照相明胶导电率测定方法; 8.照相明胶胶冻强度测定方法; 9.照相明胶氢离子浓度测定方法; 10.照相明胶水分测定方法。现选择其中主要内容编译于后,供参考。     

明胶恩氏——厘泊粘度换算验证

<正> 明胶溶液的粘度是明胶的一个重要质量指标。我国一直沿用恩氏粘度法测量明胶的粘度,而且还用恩氏粘度的大小来表示明胶的品种等级。例如:12°E、8°E、5°E食用明胶就分别代表一级、二级、三级食用明胶。故明胶制造者和明胶用户对于恩氏粘度非常熟悉和习惯     

明胶食品烹调艺术

<正> 一、明胶的应用技术 1.明胶的溶解 (1) 量取一定量的热水倒入杯中; (2) 将一定量的明胶倒入热水中; (3) 用一只叉子快速剧烈地搅拌,使明胶全部溶化为止。 2.明胶溶液的准备明胶溶液在使用前必须彻底搅拌,使溶液处于均匀状态。如果溶液中明胶含量太大,在应用前可加热水稀释,使溶液浓淡恰当,凝冻后冻力适宜。 3.明胶溶液状态的保持将盛明胶溶液的容器放在热水中保温,使保持溶液状态;如已凝冻,同样可以用热水加温融化。 4.大量明胶的溶化应先将明胶用冷水溶胀,然后再加热溶     

照相明胶板框过滤问题的讨论

<正> 在明胶生产工艺过程的提胶工序所得到的提取液中,不可避免地混有不少的骨素碎屑、脂肪碎粒、无机杂质等颗粒物,严重地影响到明胶溶液及最终产品明胶的透明度。而明胶透明度这一技术指标对于食用明胶、药用明胶,特别是照相明胶是至关重要的。为了除去     

明胶微生物污染与腐败变质的探讨

<正> 明胶是细菌培养基中的主要成分,这是基于明胶易于受到污染微生物侵袭的这一特性,因此明胶的消毒在明胶加工中成为必须考虑的一个重要问题。明胶消毒不是一种在产品简介上的形式要求,而是提高明胶质量的一个重要环节,必须加以强调。     

国外食用明胶的品种及其应用

<正> 在我国,明胶的品种按照用途,主要分为照相明胶、食用明胶和工业明胶三大类。今后,我国明胶产品若要进入国际市场,产品的品种与质量必须适应国际市场的要求。本文试图概括地介绍国外食用明胶的品种、质量及其应用,为我国明胶工业赶超国际水平提供技术信息。一、国外食用明胶的品种及其应用技术在国际市场上,明胶主要分为照相明胶、食用明胶、医药用明胶,以及用于其他工业的技术明胶(technical gelatin)。其中,所占比重最大的是食用和医药用明胶。根据工艺的不同,明胶又分为A型明     

照相明胶中硫元素的化学形态

<正> 3 照相明胶中硫元素化学形态的研究 硫是明胶中重要的非金属元素,明胶体系的许多性质以及对卤化银感光体系的影响,都与其中的硫元素(不论是明胶本身所具有的含硫氨基酸,还是明胶中的含硫杂质)关系密切。因此,研究明胶中硫元素的不同化学状态及其相对含量,探讨明胶生产过程中外来杂质铁对明胶中硫元素化学形态的影响以及明胶中硫     

明胶文摘

用组成分析法区分牛明胶和猪明胶;脱酰胺作用对胶原-明胶转变稳定性的影响;尼罗河鲈鱼皮和骨明胶的提取以及物理-化学表征;高压法提取鱼皮明胶;傅立叶转换红外分光光谱研究由尼罗河幼年和成年鲈鱼的皮和骨制得的酸溶胶原和明胶……     

明胶技术的发展与应用

<正>明胶质量的提高与稳定,明胶品质的优良,离不开明胶技术的研发与探索。十余年来,河南省焦作金箭实业总公司一直开展着明胶生产工艺技术的研发,并取得了可喜的进展,现简要介绍如下:一、明胶杂质絮凝澄清技术的研发进展情况明胶在提取过程中含有杂质及非胶原蛋白的存在,特别是末道明胶溶液中的杂质和非胶原蛋白较多导致明胶溶液较为混浊。除去     

“紫金Ⅱ”明胶半成品配胶计算程序

<正> 明胶系列产品有:照相明胶、食用明胶、医药明胶、工业明胶、皮胶等。明胶的生产过程由于批、道不同,所得明胶的质量也不同,而且每一批产品数量很小,用户购买明胶产品时,因使用范围不同,对产品有不同质量要求。为此,生产厂家就必须将各种不同的明胶半成品搭配成用户需要的明胶产品,此即为“配胶”。利用紫金Ⅱ(APPLEⅡ)明胶半成品配胶计算程序就可以解决上述问题。一、计算程序的特点 1.硬件环境:紫金Ⅱ微型计算机,环球超级中文卡。     

明胶代用物AN—BA共聚物的合成和应用

用乳液聚合法合成的丙烯酸丁酯-丙烯腈共聚物是一种性能优良的明胶代用物,而采用无机—有机复合乳液聚合技术合成的含硅的丙烯腈-丙烯酸丁酯共聚物乳液,作为明胶代用物,不仅保留原共聚物的性能,又有良好的渗透性,可改善胶片的照相性能,适用于高温快显机器加工的照片。     

Tunable thermosensitivity in multistimuli-responsive terpolymers

We designed new terpolymers responsive to pH, temperature, and metal ions. Binding of metal ions amplifies the magnitude of thermal response. Variations in the pH and concentration of metal ions enable tuning the lower critical solution temperature (LCST) and thermosensitivity in a broad range. Upon changes in pH and/or temperature, polymers form associates with narrow size distribution ranging from less than 5 nm to more than 250 nm in diameter. The multistimuli-responsive properties of newly synthesized polymers are the result of combining hydrophobic, ionogenic, and non-charged hydrophilic moieties within the terpolymer structure. Polymers are produced by a potentially scalable method from inexpensive starting materials, 2-hydroxyethylacrylate (HEA), butylmethacrylate (BMA), and acrylic acid (AA). Polymers and their aggregates are characterized by NMR, dynamic light scattering, and electron microscopy. The ability to control the size of polymer aggregates and the magnitude of response to external stimuli opens exciting opportunities for practical applications.     

1025型航空胶片沙眼问题分析

2008年某公司生产的1025型航空摄影胶片航拍冲洗加工后画面出现了大量沙眼问题,严重影响了航空摄影图像的判读。经过大量实验分析,确认引起沙眼问题的原因是胶片背面的防光晕层中的染料含盐量偏高,在高温高湿的环境下逐渐析出附着在胶片乳剂面上,从而影响了胶片的感光,使之航空摄影图像上出现了密集不均匀分布的沙眼。通过更换胶片的染料解决了沙眼问题,保证了用户的正常使用。     

Melt processing and characterization of polyvinyl alcohol and polyhydroxyalkanoate multilayer films

Multilayer films for food packaging applications composed of polyvinyl alcohol (PVOH) as the core layer and polyhydroxyalkanoate (PHA) as the outer skin layers were produced by the co‐extrusion process. Rheological properties of PVOH and PHA were performed and analyzed before co‐extruding into a cast film. Analysis of the rheological data indicated the processing temperatures and grades of the PVOH and PHA polymers that would produce similar viscosity and melt flow properties. To improve adhesion of the layers, PHA was grafted with maleic anhydride using a dicumyl peroxide initiator to provide a tie layer material, which improved the peel strength of the PHA and PVOH layers by over 2×. Oxygen transmission rate (OTR) testing showed that the multilayer sample provided an OTR of 27 cc/m²‐day at 0% relative humidity (RH) and rates of 41 and 52 cc/m²‐day at relative humidity values of 60% and 90% RH, respectively. This indicates significant barrier performance enhancement over monolayer PVOH that provided an OTR of 60 cc/m²‐day at 0% RH and 999 cc/m²‐day at 60% RH. Biodegradation testing of the films in the marine environment showed that both the unmodified and maleated PHA polymers displayed high levels of mineralization, whereas the PVOH material did not. © 2012 Wiley Periodicals, Inc. J. Appl. Polym. Sci., 2013     

The effects of varying the polymer composition on the cut growth characteristics of E/P/1,4 HD tire treads

Experimental ethylene–propylene–1,4-hexadiene polymers covering a range of compositions which possess satisfactory processing characteristics and economics have been evaluated in passenger car tires with emphasis on groove cracking. The tearing energy criterion was used in a laboratory test to correctly predict the groove cracking behavior of the tires made from these polymers. Road tests indicate that ethylene–propylene–1,4-hexadiene tripolymers containing 36%–42% propylene and 1.8%–2.2% diene exhibit resistance to cut growth and abrasion which is superior to standard SBR–BR bias tires. Polymers containing more than 42% propylene or 2.2% diene were inferior in wear and resistance to groove cracking, but sufficient data are not available to pinpoint the reason.     

Photoregulated sorption dyes to polymers. II. Adsorption of acid yellow 38 to hydrophilic polymers and its light-induced desorption

Adsorption of Acid Yellow 38 to, and its light-induced desorption from, various coated polymer layers in water have been studied. Diffusion studies were used to determine the degree of competitive binding between the dye and polymers. It was found that the extent of both adsorption and desorption were different for polymer mixtures as compared to single polymer films. The presence of gelatin crosslinked within the polymer layer increased the amount of dye desorbed upon irradiation.     

某些助剂对明胶的凝胶强度的影响的研究

众所周知,物理力学性能是照相明胶的一种很重要的属性。在各种彩色及黑白胶片都面向高温快速加工发展的今天,这种属性就显得更为重要。提高胶片的物理力学性能,一方面要从提高明胶本身的胶冻强度着手,例如减少明胶中溶胶组份(分子量小、冷水中溶解度高),提高明胶中的α和β组份的相对含量,减少分子量过大的组份等等。但是,明     

3-D structure-property relationships in rolltruded polymers. Part I: Mechanical property enhancement in three directions

The effect of rolltrusion, a solid state deformation process, on the three dimensional mechanical properties of several polymers has been measured. Polymers studied included isotactic polypropylene (iPP), polyvinylidene fluoride (PVDF), and propylene/ethylene block copolymers. It was found that mechanical strength is enhanced triaxially for all these specimens upon rolltrusion. Material stiffness also exhibits 3-D improvement, depending on the polymer type and processing conditions. These new results are discussed in regard to some structural models in the literature.     

Melt electrospinning writing of three‐dimensional star poly(ϵ‐caprolactone) scaffolds

In the last decade, the melt‐electrospinning technique has gained attention for the production of highly porous microfibrous tissue engineering scaffolds. The possibility of processing polymers without the use of organic solvents is one of the main advantages over solution electrospinning. In this study, computer‐controlled melt‐electrospinning of a commercial poly(?‐caprolactone) and of two batches with different molecular weights of a three‐arm star poly(?‐caprolactone) by means of a screw‐extruder‐based additive manufacturing system is reported. Experimental parameters such as processing temperature, extrusion flow rate and applied voltage were studied and optimized in order to obtain non‐woven meshes with uniform fibre morphology. Applying the optimized parameters, three‐dimensional scaffolds were produced using a layer‐by‐layer approach (0 ? 90° lay‐down pattern). © 2013 Society of Chemical Industry