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71.
Lin-Song Cui Shou-Cheng Dong Yuan Liu Mei-Feng Xu Qian Li Zuo-Quan Jiang Liang-Sheng Liao 《Organic Electronics》2013,14(7):1924-1930
This study investigated the use of a novel modification in molecular design to get two new electron-transport host materials, SF3PO and BSF3PO. By linking the phosphine oxide moieties at meta-position of spirobifluorene rings, higher triplet energies could be easily achieved for these two new materials. The steric spirobifluorene structures could guarantee their good thermal stabilities. According to these properties, their applications as host materials for deep blue phosphorescent organic light-emitting diodes (PHOLEDs) were explored. As expected, the deep blue emitting devices with Ir-complex FIr6 as phosphorescent dopants and SF3PO and BSF3PO as hosts had been fabricated and showed high efficiency of 28.5 and 22.0 cd/A, respectively, which were significantly higher than that of the para-linked analogue SPPO1. 相似文献
72.
《分离科学与技术》2012,47(4):983-994
Abstract A rapid, selective, and sensitive cloud point extraction process using mixed micelle of a nonionic surfactant, Triton X-114, and an anionic surfactant, SDS, to extract sulfide from aqueous solutions was investigated. The method is based on the color reaction of sulfide with N,N-diethyl-p-phenylenediamine (DPD) in the presence of suitable oxidizing reagent (Fe3+) in acid media and cloud point extraction of ethylene blue (EB) dye. Various factors and optimal extraction and reaction conditions like: acid, Fe3+, reagent, and surfactant concentration were studied and the analytical characteristics of the method (e.g., limit of detection, linear range, RSD%) were obtained. Linearity was obeyed in the range of 1–100 ng mL?1 of sulfide ion. The detection limit of the method is 0.5 ng mL?1 of sulfide ion. The interference effect of some anions, cations, and neutral species was also tested. The method was applied to the determination of sulfide in spring, river, and waste water samples. 相似文献
73.
《Food Control》2016
Surface-enhanced Raman spectroscopy (SERS) is an emerging technology with great potential for sensitive and rapid analysis of trace methylene blue (MB) in fish muscle. Five different SERS substrates including two commercial nanostructured surface substrates and three types of Au nanoparticles (NPs) with different diameters were compared to optimize enhancement effects. The highest sensitivity with the lowest detection limit of 5 ng/mL for MB standard solutions and 10 ng/g for MB in fish muscles was achieved using the 18 ± 2 nm Au NPs. Partial least squares regression models developed for quantitative analysis showed high linear correlation between the actual and predicted values for MB (R2 cv = 0.958, RPD = 4.84, RMSE = 6.97 ng/g) in fish muscle. Since Au NPs are easy to prepare, stable and affordable, the high sensitivity and predictability of this method has the potential to be widely used for trace analysis of prohibited drug residues in fish and potentially other foods or biological samples. 相似文献
74.
Raw milk is a complete food which contains protein, fat, sugars, vitamins and minerals. Even though, raw milk is sterile at secretion, contamination of milk by microorganisms can take place during milk handling, storage and other pre-processing activities. The objectives of this study were to assess the initial microbial load and to determine correlation between Methylene blue dye reduction test with standard plate count method and find possible methods to improve the quality and reduce the wastage of raw milk. As per the records obtain from the chilling centers, about twenty per cent (per month) of raw milk collected to the centers in each district has to be discarded due to spoilage. Out of 13 chilling centers in Kurunagala district, five chilling centers namely Badalgama, Elabadagama, Kuliyapitiya, Dambadeniya and Minuwangoda chilling centers were randomly selected and the initial microbial loads of milk from chilling tanks were tested using Standard Plate Count and Methylene blue dye reduction test. Further, Self- filled questionnaire was used to gather data related to practices in milk supply chain and swab samples were taken from the containers used for milk collection process. Though the microbial population should be below log 6.00 according to the factory standards in Sri Lanka to accept milk for further processing, standard plate count of chilling centers were log 7.08, 6.76, 6.56, 6.70, and 6.88 (CFU/ml) respectively. Good management practices were introduced to rectify the main cause for high microbial counts. After the improvements low microbial counts of above chilling centers were achieved as log 5.91, 5.85, 5.85, 5.86 and 5.94 CFU/ml respectively. Standard Plate Count showed significant difference (p < 0.05) after practicing good management practices. Strong correlation (r2 0.91) was observed between Methylene blue dye reduction test and Standard Plate Counts (log CFU/ml). Therefore, Methylene blue dye reduction test can be used effectively, economically and efficiently, to detect the quality of raw milk and can use as an alternative method for costly and tedious microbiological analysis methods. 相似文献
75.
Phosphorescent OLEDs: Sky‐Blue Phosphorescent OLEDs with 34.1% External Quantum Efficiency Using a Low Refractive Index Electron Transporting Layer (Adv. Mater. 24/2016) 下载免费PDF全文
76.
TiO2/活性炭复合体超临界沉淀法制备及其光催化性能 总被引:1,自引:0,他引:1
以活性炭为载体、超临界二氧化碳为流体、钛酸丁酯为前驱体,用超临界流体沉积法制备TiO2/活性炭(TiO2/AC)复合体。用X射线衍射(XRD)、扫描电镜(SEM)、比表面积分析(BET)、热重-差热(TG-DTA)对TiO2/AC进行表征。以紫外灯为光源,偶氮类染料亚甲基蓝为标准降解物,考察TiO2/AC复合体的光催化... 相似文献
77.
采用甘氨酸-硝酸盐燃烧法成功制备了La0.7Ca0.3Fe0.25Co0.75O3钙钛矿型复合氧化物,以(NH4)2S2O8为氧化剂,运用化学氧化法合成La0.7Ca0.3Fe0.25Co0.75O3/聚吡咯薄膜,然后通过静电自组装方法制备了一种新的表面负载修饰型复合光催化剂La0.7Ca0.3Fe0.25Co0.75O3/PPy/PMO12。采用XRD、SEM、FT-IR对催化剂的物化结构进行了表征。光催化性能测试是以亚甲基蓝染料的水溶液为降解目标,结果表明,PMo12的负载修饰改进了La0.7Ca0.3-Fe0.25Co0.75O3/PPy光催化剂的催化活性。 相似文献
78.
79.
80.
可见光下磷钨酸盐光催化降解分散蓝130的研究 总被引:1,自引:0,他引:1
用磷钨酸分别与可溶性盐反应合成了三种磷钨酸盐(磷钨酸钾、磷钨酸铵和磷钨酸铯),采用XRD及TG对样品进行表征,结果表明,磷钨酸盐保持着Keggin结构的稳定性,且热稳定性能良好。考察了制备得到的磷钨酸盐在可见光照射下对分散蓝130的光催化降解性能,实验表明,磷钨酸钾的最佳活化温度为300℃,而磷钨酸铵和磷钨酸铯则无需活化即具有较好的光催化降解性能。在三种磷钨酸盐中,磷钨酸铵的光催化降解性能最好,其中,当磷钨酸铵的最佳投加浓度为6g/L、双氧水最佳浓度为0.048%时,无需活化的磷钨酸铵对阴离子染料分散蓝130的光降解率可达55%以上,回收重复使用5次后,光降解率仍可达到56.5%,催化剂可以循环使用且性能良好。 相似文献