共查询到20条相似文献，搜索用时 125 毫秒
1.
陈共珏 《重庆第二师范学院学报》2003,16(6):53-55,82
高师化学专业分析化学实验中有“铜、铁、钴、镍的纸上层析分离法”的实验，但所需显色剂二硫代乙二酰胺长期缺货，使该实验难以开出，笔者研究了替代显色剂及有关实验条件，发现用K4Fe(CN)6 K3Fe(CN)6混合液作显色剂，可保证Cu^2 、Fe^3 、Co^2 离子的色斑清楚显示，但显色剂造成的黄绿色背景使Ni^2 色斑辨认困难．若用K4Fe(CN)6 K3Fe(CN)6 丁二酮肟混合液显色，然后用浓氨水薰，则Ni^2 可形成清晰的红色斑点．使用这两种显色剂时，层析滤纸事先不在展开剂中饱和，分离效果更好；浓氨水也不宜在喷洒显色剂之前使用． 相似文献
2.
用二甲酚橙做显色剂测定硫酸锌糖浆的含量结果,与用锌试剂、PAN法基本一致。本法所用显色剂价廉、易得。 相似文献
3.
介绍了用聚丙烯酰胺（PAAM）改性聚乙烯醇缩甲醛胶粘剂（PVF）的新生产工艺，研制出的PVF胶粘剂具有粘度强、粘接强度大、游离甲醛量低等优点，产品性能达到建材行业有关标准要求。 相似文献
4.
刨花板用脲醛树脂改性方法的研究 总被引：1，自引：0，他引：1
王华兰 《温州职业技术学院学报》2003,3(2):50-53
本丈针对木材用脲醛树脂胶耐水、耐热性差、游离甲醛含量高等缺点，研究了脲醛树脂的改性方法，通过降低尿素与甲醛的摩尔比、改变投料方式、加入改性组分等方法可获得性能优良的改性脲醛树脂。 相似文献
5.
6.
李江群 《中学生数理化(高中版)》2006,(3):86-88
甲醛（HCHO）又名蚁醛，常温下是一种无色气体，有刺激性气味，易溶于水，35％～40％的水溶液叫做福尔马林，甲雌在工业上主要用于制取酚醛树脂、氯霉素、香料、染料等许多有机化合物．甲醛的水溶液具有杀菌、防腐性能，广泛用于动、植物防腐剂，用它浸润过的木头可防止虫蛀，也用于涂料的溶剂，因此，新装修的房屋或新购置的家具，在很长一段时间内一般都会慢慢释放出甲醛气体，导致空气污染，长期在含有甲醛的地方生活会导致呼吸道疾病，也可诱生其他多种疾病。 相似文献
7.
参照土壤磷酸酶的测定方法,研究了2,6-双溴苯醌氯酰亚胺、2.5%的铁氰化钾和0.5%的4-氨基安替吡啉2种显色剂对土壤磷酸酶活性测定结果的影响。结果表明:当天配制的2,6-双溴苯醌氯酰亚胺与配制当天、配制第2天和第3天的2.5%的铁氰化钾和0.5%的4-氨基安替吡啉作显色剂测定的磷酸酶活性差异小,没有达到显著性差异;配制当天、配制第2天和第3天的2.5%的铁氰化钾和0.5%的4-氨基安替吡啉作显色剂测定的磷酸酶活性没有差异;而用配制第2天和第3天的2,6-双溴苯醌氯酰亚胺作显色剂与配制当天的2,6-双溴苯醌氯酰亚胺作显色剂测定的磷酸酶活性差异大,达到了显著和极显著差异水平。测定磷酸酶活性可以用2.5%的铁氰化钾和0.5%的4-氨基安替吡啉代替2,6-双溴苯醌氯酰亚胺作显色剂。 相似文献
8.
分光光度法测定磺胺类药物的含量 总被引：1，自引：0，他引：1
用α－萘酚作显色剂分光光度法测定磺胺药物含量的方法，与标准方法相比，该法具有操作简单、试剂消耗秒、结果重现性好，分析速度快，且在常温下即可测定等优点，为磺胺类药物含量的快速准确测定提供了一种简便的方法。 相似文献
9.
刘小英 《泉州师范学院学报》2005,23(4):51-54
用非等温热重法研究了腰果酚甲醛铁聚合物的热分解反应动力学,结果表明：腰果酚甲醛铁聚合物的热分解过程是一级反应，用Ozawa法和Reich法求得的平均活化能分别为191．1kJ／mol和191．0kJ／mol。 相似文献
10.
玻璃盒镶蝴蝶标本的制作长庆三中张焕欣制作材料玻璃，三合板（长宽各１８．５ｃｍ），蝴蝶，小叶植物的叶、花，方木框架（长宽各２０ｃｍ）。仪器药品展翅板、５ｍｌ针管、小钉子、甘油、甲醛、樟脑。制作过程１．防腐整形。首先用注射器吸取４０％的甲醛液和少量甘油注... 相似文献
11.
将抽象因子分析法用于解析配合物体系的吸光度数据以确定体系中的吸光物种数，为研究表面活性剂对金属离子与显色剂反应体系增敏作用机理提供一种新方法。用该法对Fe（Ⅲ）-SCN和Fe（Ⅲ）-SCN-Tween-80两显色体系的吸光度数据进行处理，结果表明，新的多元配合物的生成是表面活性剂对Fe（Ⅲ）-SCN显色反应增敏的主要原因。 相似文献
12.
Using texture synthesis in fractal pattern design 总被引：2，自引：0，他引：2
INTRODUCTIONIn the last two decades, research on fractal ge-ometry has received much attention for its theoretical significance and practical applications. Pattern design based on fractal geometry is an important application area of fractal techniques in the textile industry (Wang, 2003). Computer aided pattern design involves the de-sign of textures and colors in the pattern. The source of textures is rich. All kinds of objects and scenery including man-made abstract objects can be used… 相似文献
13.
绿色蔬菜在加热处理时,很容易失去鲜绿色而形成褐色,如何保持绿色蔬菜在加工或贮存过程中叶绿素的稳定性问题,成为亟待解决的问题。以菠菜为材料,采用添加护绿剂作为护绿方法,利用分光光度法对其中的叶绿素进行测定,了解不同护绿剂的护绿效果,同时采用不同的温度、超声波、紫外线处理护绿后的叶绿素提取液．分析护绿剂护绿后叶绿素的稳定性。 相似文献
14.
4 studies investigate how differential input affects preschoolers' abilities to learn novel color words. 3-, 4-, and 5-year-old children saw objects in novel shapes and colors and heard a novel color label for the object. Labels were presented through ostensive definition (e.g., "See, it's mauve"), corrective linguistic contrast (e.g., "See, it's not purple; it's mauve"), or an inclusion statement (e.g., "See, it's mauve; it's a kind of purple"). 4- and 5-year-old children interpreted the novel word as a shape term when ostensive information was provided but as a color term when additional information, either contrastive or inclusive, specified a relation between the novel term and a known label for that color. Furthermore, children who consistently interpreted the novel word as a color word tended to treat the novel and known labels as mutually exclusive color terms if they heard contrastive information, whereas they tended to treat the words as hierarchically related if they heard inclusion information. 3-year-olds generally did not make use of either type of information in determining the semantic domain of the novel word or the relation between terms. 相似文献
15.
目的：建立美洲大蠊抗肝纤维化活性提取物ML-D中粘多糖的含量测定方法。方法：采用苯酚-硫酸法测定粘多糖的含量,采用正交试验设计考察ML-D中粘多糖的水解工艺和显色条件,采用单因素试验考察加热显色时间、苯酚和硫酸的用量。结果：ML-D中粘多糖的最佳水解工艺为：盐酸浓度6 mol/L,固液比为1∶1,水解时间1 h;最佳显色条件：苯酚2 mL,硫酸20 mL,加热显色时间10 min。结论：该法操作简便,精密度高,重复性好,可作为美洲大蠊抗肝纤维化活性提取物ML-D中粘多糖含量的测定方法。 相似文献
16.
Pigeons were trained on a successive discrete-trial conditional discrimination, in which either of two colors appeared on the center key and either of two forms appeared on the two side keys. Some combinations of color and form (S+ trials) were followed by food; other combinations (S-trials) were followed by no food. The colors on the center key appeared throughout the intertrial interval (ITI) preceding the trial period in which both the color and the form compound were presented or the color appeared only during the trial period in compound with the forms. Presentation of the colors during the ITI substantially degraded acquisition of two separate types of conditional discrimination. The results show that the temporal correlation of the eolors-with food, independent of their association with the form cues, played a substantial role in determining their availability for acquisition of the conditional discrimination. 相似文献
17.
翻译中词语推敲的目的，在于寻找出那些即能体现原原意又生动贴切的词语来表现原词，来表现原词所表现的事物。而词语的表现力则包含词义、音韵、色彩三个因素。因此在词语推敲的过程中，要准确把握词语在意义、色彩、音韵等方面的特色，恰当贴切地选词用词。 相似文献
18.
《校园英语(教研版)》2015,(25):213-214
English and Chinese color words have many different meanings under different cultural backgrounds,so it is very important to translate English and Chinese color words.With more and more communication between China and England,different translation of color words in commercial activities and daily communication,and that will lead to unnecessary misunderstandings,so it has the practical and theory significance to explore the translation of English and Chinese color words.We can grasp the principles and ways in translating color words better,and it also can help us to easily understand the differences between English and Chinese color words. 相似文献
19.
蕨菜保鲜贮藏技术研究 总被引：1，自引：0，他引：1
以蕨菜为原料,研究安全性好、成本较低、保鲜效果好的蕨菜保鲜方法．保存液配方为维生素C0．10％,氯化钙0．30％,山梨酸钾0．05％,食盐1．00％,100℃灭菌3min．用此方法保鲜蕨莱安全性完全符合国家规定,在30℃下至少能保鲜3个月,在室温条件下保存一年也尚未完全失去商品价值． 相似文献
20.
Color control of the multi-color printing device 总被引：4，自引：0，他引：4
WANG Xiao-hua XIU Xiao-jie ZHU Wen-hua TANG Hong-jun 《浙江大学学报(A卷英文版)》2006,7(7):1187-1192
INTRODUCTION During the development of printing technology, digital printing has played an important role. Now various kinds of multi-color digital inkjet printers are available. Compared with the conventional digital inkjet printer, the multi-color digital inkjet printer has larger color gamut and can faithfully produce more colors. The conventional color printing devices nor- mally use three or four inks, e.g., CMY, CMYK. Although some adopt more than four inks, e.g., CMYKLcLm, the… 相似文献