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用百里酚蓝—亚甲蓝混合指示剂测定季胺盐型阳离子表面活性剂 总被引:1,自引:0,他引:1
针对目前测定季铵盐型阳离子表面活性剂常用方法存在的问题和不足 ,提出了一种新的测定方法——百里酚蓝 -亚甲蓝混合指示剂法 .该法采用了百里酚蓝和亚甲蓝两种常见的指示剂进行测定 ,与国际标准 ISO- 2 781法及传统亚甲蓝法进行比较 ,结果表明 ,采用本方法比国际标准方法药品易得 ,测定成本低 ,毒性小 ,操作方便 ,测定误差 <0 .3% (与国际标准方法等效 )比亚甲蓝法的测定结果 (误差 <1 % )准确度高 ,且终点变化明显 ,容易观察到 . 相似文献
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《中华纸业》2015,(6)
研究了分别添加中性表面活性剂和阴离子表面活性剂改性后水性油墨的干燥速度,同时表征改性后水性油墨的固含量、黏度、pH值、色差和色密度等性能的变化。研究表明:添加中性表面活性剂与阴离子表面活性剂,均能有效提高水性油墨的干燥速度。其中,中性表面活性剂含量为0.50%时,初干时间为10.96s,水性油墨的干燥速度有明显提高,相比原墨提高了8.89%;阴离子表面活性剂含量为0.83%时,初干时间是10.25s,比原墨干燥速度提高了14.50%。同时,对比水性油墨其他性能,研究发现当中性表面活性剂含量为0.50%、阴离子表面活性剂含量为0.83%时,其水墨各项性能与原墨差异不大。 相似文献
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荧光素作吸附指示剂测定1227表面活性剂的含量 总被引:1,自引:0,他引:1
本文以荧光素作沉淀吸附指示剂,用AgNO3滴定1227表面活性剂中的Cl^-离子,从而测出1227表面活性剂的含量,方法快速,简便,结果令人满意。 相似文献
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固体微粒稳定的乳液可以避免表面活性剂的不利影响.以纳米尺寸的锂石颗粒为乳化剂,以正丁胺为锂皂石的改性剂,制备了稳定的ASA乳液,并对其施胶性能、水解稳定性进行了研究.结果表明,当水相pH值为6,锂皂石对ASA用量为1.5%,正丁胺对锂皂石用量为2%时,利用改性锂皂石可以制备稳定的ASA乳液.所制备的ASA乳液可以产生良好的施胶效果,但其水解稳定性较差.铝盐的加入可以显著提高ASA乳液的施胶性能,而且在高铝盐添加量下,即使不使用助留剂,ASA乳液也能产生很好的施胶效果. 相似文献
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陈全伦 《国外纺织技术(纺织针织服装化纤染整)》1979,(4)
一、阴离子表面活性剂碱分层滴定法本法由于是在碱性正丙醇—水体系中使用溴甲酚绿指示剂,用阳离子表面活性剂进行滴定的方法,所以肥皂与磺酸盐,硫酸酯盐等其它阴离子表面活性剂也同时定量。 相似文献
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为了正确将表面活性剂使用到制革的酶处理工序中,本试验分别在胰酶和AS1.398酶溶液中添加质量浓度10%的明胶和不同量的十二烷基苯磺酸钠(阴离子型表面活性剂)、十二烷基三甲基氯化铵(阳离子型表面活性剂)和平平加O(非离子型表面活性剂),来测定不同表面活性剂对酶活力和明胶水解程度的影响。试验表明:3种表面活性剂对酶活均起到激活作用;但添加阴离子型表面活性剂后,明胶的水解程度提高。为了探究它们在溶液中所起的主导性作用,在试验第二步,将3种表面活性剂加入到质量浓度0.4%明胶+酶的混合液中,研究混合液在37℃时的Zeta电位的变化。试验表明:加入阴离子型,Zeta电位的绝对值提升;加入阳离子型,Zeta电位从负变为正;加入非离子型,Zeta电位绝对值降低。结合实际制革生产中对皮革高性能的要求,研究表明:在进行酶软化时,应优先选择非离子型表面活性剂。 相似文献
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Bambang Kuswandi Chrysnanda Maryska Jayus Aminah Abdullah Lee Yook Heng 《Sensing and Instrumentation for Food Quality and Safety》2013,7(1):29-39
A novel on-package color indicator has been fabricated based on bromophenol blue, and tests have been conducted to assess the freshness of guava (Psidium guajava L.). Bromophenol blue (BPB) was immobilized onto bacterial cellulose membrane via absorption method. The BPB/cellulose membrane as color indicator works based on pH decrease as the volatile organic compounds (e.g. acetic acid), produced gradually in the package headspace during developing of guava. Subsequently the color of the indicator will change from blue to green for over-ripe indication, which can be visible to the naked eye. The results showed that the color indicator could be used to determine the state of freshness of the guava at ambient condition (28–30 °C). The color change of the indicators reflects the pH of headspace of the guava packaging. Furthermore, it also in similar trends to the change of several parameters (soluble solids content, texture and sensory evaluation) that normally used to characterize the freshness of guava. Therefore, the indicator can be used for real time visual monitoring of freshness state of packaged guavas. 相似文献
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A simple bromothymol blue indicator test was evaluated for farm diagnosis of mastitis. The test required highly absorbent blotting paper impregnated with four spots of bromothymol blue. Indicator color scores (1 to 4) for quarter foremilks increased with somatic cell count and pH, although variability within each color score was large. Sensitivity of the bromothymol blue test ranged from 51 to 56% and specificity from 89 to 90% for most reference criteria used to classify normal and abnormal milk. Predictability of a positive test ranged from 49 to 52% (false positives 51 to 48%) and predictability of a negative test from 90 to 97% (false negatives 10 to 3%) for the same criteria. Overall the bromothymol blue test incorrectly diagnosed 11 to 20% of 3772 quarters. By classifying color score 2 as negative, predictability of a positive result was 70 to 75% and sensitivity was 26 to 30%. The test can be used by dairy producers to screen herds with a relatively high incidence of mastitis or used in combination with cow cell counts to locate abnormal quarters. The bromothymol blue test was less sensitive than the California Mastitis Test but offered several practical advantages for use on farm. 相似文献
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近年来,智能检测食品新鲜度的比色膜受到越来越多的关注。本实验利用静电纺丝技术研制出一种溴麝香草酚蓝(bromothymol blue,BTB)/玉米醇溶蛋白(zein,ZN)新型智能比色标签,用于金枪鱼鱼片的新鲜度监测。BTB在pH值为5~12时的明显颜色变化赋予了指示标签灵敏的pH值传感效果。通过场发射扫描电子显微镜、傅里叶变换红外光谱、X射线衍射、差示扫描量热仪对不同BTB添加量的BTB/ZN指示标签的形貌和结构进行表征。再将BTB/ZN指示标签应用于金枪鱼鱼片新鲜度的指示验证实验,对指示标签的指示效果进行验证。结果表明,BTB/ZN指示标签的微观结构良好,BTB可以很好地与ZN结合在一起,并且不破坏二者的结构;质量分数4% BTB的BTB/ZN指示标签的指示效果最佳,能灵敏地反映金枪鱼的新鲜度变化。指示标签的色度和金枪鱼鱼肉的总挥发性盐基氮含量之间存在显著相关性,这证明BTB/ZN指示标签能有效监测金枪鱼鱼片的新鲜度。 相似文献
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本研究以食品包装中二氧化碳含量作为监控指标,以二氧化碳敏感型指示剂甲基红和溴百里酚蓝与成膜材料甲基纤维素、甘油,混合制得气敏性凝胶,并以棉质纤维纸为基材制备指示卡。结果表明:在甲基红与溴百里酚蓝质量之比为3∶2,质量浓度为5%的指示溶液中添加适量的甲基纤维素、甘油后,以一定的溶液量涂布于棉质纤维纸上可制得准确显示二氧化碳含量的指示卡;采用响应面分析法得到甲基纤维素添加量、甘油添加量和溶液量的最佳参数为:甲基纤维素1.72 g/100 g;甘油4.27 g/100 g;溶液量11.39 m L。将最佳组合进行验证,测得色差的平均值为1.93,与预测值1.84十分接近。并通过实际应用验证发现该指示卡与13个二氧化碳浓度具有显著颜色变化点,各点具有明显的颜色界限,通过肉眼即可观察分辨,具有较高的实用性。 相似文献
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Dowan Kim Soni Lee Kaeun Lee Seunghye Baek Jongchul Seo 《Food science and biotechnology》2017,26(1):37-42
A colorimetric bromocresol purple dye-based pH-responsive indicator was developed to monitor the quality of chicken breast meat by direct surface contact. To prevent direct contact of the dye with the chicken breast and to improve its color change sensitivity, it was immobilized with polyvinyl alcohol and a high-absorbance material. The color of the pH indicator changes from yellow to blue and finally purple to indicate spoilage, which can be easily detected by the naked eye. The asprepared pH indicator exhibited good response to pH changes on the surface of chicken breast meat, and no migration of the dye from the indicator onto the surface of the chicken was observed. This pH indicator exhibits excellent feasibility for real-time, direct-contact monitoring of the freshness and quality of various foods. 相似文献
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以马铃薯淀粉(starch,S)、羧甲基纤维素钠(carboxymethyl-cellulose sodium,CMC)以及魔芋葡甘露聚糖(konjac glucomannan,KMG)两两互配为成膜基材,紫薯花青素(P)作为新鲜度指示剂,制备智能指示膜,比较KMG/S/P(KSP)、S/CMC/P(SCP)、KMG/CMC/P(KCP)3 种智能指示膜的力学性能、水分质量分数、水溶性、微观结构、相容性及稳定性等的差异,并运用鱼肉进行初步应用评价。结果表明:SCP膜的抗拉伸强度最高((15.39±1.15)MPa)、水溶性最低((24.17±1.21)%),且颜色稳定性好;而KCP膜断裂伸长率最大((44.79±1.43)%);扫描电子显微镜观察结果表明不同智能指示膜微观结构差异明显,其中SCP膜横切面光滑紧密。利用SCP检测鱼肉新鲜度,25 ℃下鱼肉贮藏24 h后挥发性盐基氮含量达15.2 mg/100 g,已经开始腐败,此时智能指示膜显示出浅红色,48 h后变为浅蓝色。因此,SCP膜适合新鲜度检测,且运用紫薯花青素开发稳定的指示膜有良好的应用前景。 相似文献