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931.
In this study, we successfully prepared a polyacrylamide (PAM) water‐in‐water (W/W) emulsion through dispersion polymerization with only a small concentration of gelatin as the stabilizer. Types of identical methods were used to study the structure of this material, among which Fourier transform infrared and 1H‐NMR spectroscopy indicated that the polymer was composed of PAM and a few gelatin, transmission electron microscopy (TEM) verified the W/W emulsion structure, and gel permeation chromatography confirmed the existence of the graft polymer of gelatin and PAM. In addition, TEM and dynamic light scattering confirmed the morphology and particle size distribution of the PAM W/W emulsion particles and demonstrated that the formation mechanism of the particles during the polymerization process was quite fitted with phase‐separation theory. The effects of the temperature, pH value, and gelatin concentration on the properties of the PAM W/W emulsion were also investigated systematically. Moreover, PAM W/W emulsions prepared with various gelatin concentrations were applied to the flocculation of Reactive Turquoise Blue K‐GL; it turned out that the PAM W/W emulsion had a higher removal efficiency with increasing gelatin concentration. Therefore, the PAM W/W emulsion could be regarded as an effective flocculant for wastewater treatment; it also showed an excellent redispersion ability in water and good storage stability. © 2018 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2018 , 135, 46298.  相似文献   
932.
Novel tetra‐armed star‐shaped styrenic copolymers with pyrene side groups [ (S1‐S3)‐Pyr ] were prepared and employed as fluorescence sensing probe for fast and sensitive determination of nitroaromatic compounds. (S1‐S3)‐Pyr depicted characteristic pyrene monomer emission signals as well as broad excimer bands in their fluorescence emission spectra due to close proximity of the pyrene groups on the polymer chains and the ratio of monomer to excimer emission intensities gradually decreased as the pyrene content of the star polymers were increased from S1‐Pyr to S3‐Pyr . The highest quenching efficiency in the presence of 25 equivalent nitroaromatics was observed for 2,4,6‐trinitrophenol/picric acid (99.4%) followed by 2,4‐dinitrophenol (84.2%), 4‐nitrophenol (82.6%), 2,4,6‐trinitrotoluene (44.0%), 2,4‐dinitrotolunene (32.6%), and 4‐nitrotoluene (28.8%). Superior quenching efficiencies of nitrophenolic compounds were ascribed to their strong binding affinity for (S1‐S3)‐Pyr due to the acidity of phenolic hydroxyl units. Besides, quenching ratios of S1‐Pyr , S2‐Pyr , and S3‐Pyr were measured to be very close to each other. Thus, (S1‐S3)‐Pyr are considered to be highly selective and sensitive fluorescence probes for phenolic nitroaromatic compounds. © 2018 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2018 , 135, 46310.  相似文献   
933.
The interaction between two dyes (AO7 and AG25) during adsorption was studied in detail with diethylenetriamine‐modified chitosan beads (CTSN‐beads) as the adsorbent. Results indicate that the adsorption capacities and rates were directly related to the molecular size of the dye. The adsorption capacity and rate of AO7 could be greatly weakened by interaction with AG 25 during adsorption, which has a larger molecular size. The adsorption followed the pseudo‐second‐order kinetic equation and Freundlich model gave a satisfying correlation with the equilibrium data both in the single and binary component system. Adsorption could be divided into three stages, each controlled by different mechanisms. Temperature experiments showed high temperature was beneficial to the mass transfer of dyes. © 2014 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2014 , 131, 41168.  相似文献   
934.
The electropolymerization of thionine in an aqueous solution has been carried out by using both cycling voltammetry and chronoamperometry experiments. Electropolymerization has been applied at various pHs by using different working electrodes. The characterization of poly(thionine) thin films is performed by using cyclic voltammetry, current–time transients, atomic force microscopy, scanning tunnelling microscopy, ATR‐FTIR, and UV–vis absorption spectroscopy techniques. It is deduced from current–time transients and morphological data that poly(thionine) film forms with random adsorption process and exhibits an irregular polymeric film. Poly(thionine) film formation was compared with that of previously published results of phenothiazine derivatives of poly(azure A) and poly(methylene blue). It has been concluded that type of amine functional group of phenothiazine dyes is very effective on the formation of polymeric film structure. © 2013 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2014 , 131, 39686.  相似文献   
935.
研究了影响飞机耐流体底漆防腐性能的因素。通过试验比较,确定了树脂类型、颜填料的选择、PVC(颜料体积浓度)的控制范围及固化剂的用量,从而达到最佳的防腐性能。  相似文献   
936.
瓷釉用棕色尖晶石颜料   总被引:2,自引:0,他引:2  
ZnO-Fe2O3-Cr2O3系统是合成陶瓷工业用的大部分棕色颜料的基本三元系统。介绍了如下几种类型的棕色颜料的制备:1ZnFeCrO4,2ZnFeCrO4中部分ZnO被FeO或FeO+NiO置换,3ZnFeCrO4中部分Fe2O3、Cr2O3或Fe2O3+Cr2O4被Al2O3置换;借助X-射线衍射法和热分析,阐述了色料的形成和晶体结构;通过色釉试验,并参照色度测定的数据讨论了色料的组成与结构对色釉颜色的影响。  相似文献   
937.
Lipid oxidation and color change of salted pork patties   总被引:1,自引:0,他引:1  
The purposes of this study were to explore the interaction of lipid oxidation and pigment oxidation in salted pork patties and to study the mutual relationship between lipid and pigment oxidation caused by replacing sodium chloride with potassium chloride at low salt levels. For fresh pork patties, a and b values decreased with the replacement of sodium chloride by potassium chloride. However, there were no significant differences of L values, pH values, total pigments and heme irons by replacement of NaCl with KCl; however, the replacement reduced 2-thiobarbituric acid reactive substances (TBARS).  相似文献   
938.
Anthocyanins, the natural red and purple colorants of berries, fruits, vegetables, and tubers, improve carbohydrate metabolism and decrease the risk factors of metabolic disorders, but their industrial use is limited by their chemical instability. Acylation of the glycosyl moieties of anthocyanins, however, changes the chemical properties of anthocyanins and provides enhanced stability. Thus, acylated anthocyanins are more usable as natural colorants and bioactive components of innovative functional foods. Acylated anthocyanins are common in pigmented vegetables and tubers, the consumption of which has the potential to increase the intake of health-promoting anthocyanins as part of the daily diet. For the first time, this review presents the current findings on bioavailability, absorption, metabolism, and health effects of acylated anthocyanins with comparison to more extensively investigated nonacylated anthocyanins. The structural differences between nonacylated and acylated anthocyanins lead to enhanced color stability, altered absorption, bioavailability, in vivo stability, and colonic degradation. The impact of phenolic metabolites and their potential health effects regardless of the low bioavailability of the parent anthocyanins as such is discussed. Here, purple-fleshed potatoes are presented as a globally available, eco-friendly model food rich in acylated anthocyanins, which further highlights the industrial possibilities and nutritional relevance of acylated anthocyanins. This work supports the academic community and industry in food research and development by reviewing the current literature and highlighting gaps of knowledge.  相似文献   
939.
叙述了纺织品印花材料的分类和我国服装印花(衣片印花)材料开发的3个发展趋势:鲜艳夺目亮丽型的印花材料、变幻莫测新奇型的印花材料和实用保健功能型的印花材料.  相似文献   
940.
The changes in the quality parameters of Spanish pomegranate fruit (cultivar Mollar) during ripening and during 7 weeks of cold storage at 5°C and 90–95% relative humidity were studied. The fruit and seed weights, as well as the surface colour increased with ripening. Total soluble solids (TSS), pH and titratable acidity (TA) did not show significant differences during the weeks studied (from the 26th to 32nd weeks after flowering), but the seeds' colour (Lab values) and juice colour (absorbance at 510 nm) showed an increase during this period with a maximum during the last 2 weeks. These results indicate that pomegranates should be harvested during the 31st to the 32nd after flowering, in order to get the best pigmentation without a decrease in other quality parameters. The anthocyanin profile changed during the different maturity stages, since the diglucoside derivatives were the prevailing pigments during the early ripening stages, whereas the monoglucoside derivatives were the main pigments in the latter stages. After cold storage of pomegranates harvested at two maturity stages, no differences in TSS, pH, TA and skin colour were observed. In addition, seeds' and juice colour did not decrease during storage. Hence, this study supports the theory that pomegranate is a nonclimacteric fruit and that pomegranates can be stored for at least 45 days without deterioration in the fruit quality.  相似文献   
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