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101.
饮料中4种人工合成甜昧剂同时测定的超高效液相色谱快速检测方法 总被引：2，自引：1，他引：1
建立了采用超高效液相色谱同时测定饮料中4种甜味剂(安赛蜜、糖精钠、甜味素、纽甜)的方法.样品经简单的预处理后,通过ACQUITY UPLCTM BEH C18色谱柱分离,以乙腈-20 mmol/L磷酸二氢钠水溶液为流动相进行梯度洗脱,于220 nm波长下紫外检测.一次进样分析仅需6 min.4种甜味剂在0.5～20.0 mg/L范围内的线性关系良好,在加标水平为1,10和20 mg/L时,被测物的回收率为80.5%～95.2%,相对标准偏差为0.50%～8.7%. 相似文献
102.
Xiaogang Yang Dongsheng Li Feng Fu Long Tang Jiyuan Yang Lili Wang Yaoyu Wang 《无机化学与普通化学杂志》2008,634(14):2634-2638
The reaction of ZnII nitrate with maleic acid (H2mal) / fumaric acid (H2fum) and 4,4′‐dipyridyl disulfide (4‐pds) resulted under same conditions in two distinct interpenetrated compounds, namely [Zn(4‐dps)2(H2O)2]·2Hmal ( 1 ) and [Zn(4‐dps)(fum)] ( 2 ). In 1 , Hmal anion adopts bridging mode based on hydrogen bonding, affording a 2‐fold parallel interpenetrated 3D→3D α‐Po net hydrogen‐bonded framework, in which 1D double‐stranded chains are formed, and then extended to a 3D supramolecular architecture combining second‐sphere hydrogen‐bonded interactions. For 2 , fum dianion takes on bis‐dentate bridging coordination fashion, furnishing a 2‐fold interpenetrated 2D→2D (4,4) layered coordination network, in which the tetrahedral ZnII atoms are interlinked by 4‐dps and fum. Additionally, the compound 2 shows strong fluorescence in the solid state at room temperature. 相似文献
103.
Zhen Yu Yuping Duan Lidong Liu Shunhua Liu Xujing Liu Xiaogang Li 《Surface and interface analysis : SIA》2009,41(5):361-365
Hot‐dipped aluminum copper with plating auxiliary KF is introduced in this work. In this study, the intermetallic layer thickness varies with dipping temperature and time in a linear relationship. The main phases are identified to be CuAl2 and K3AlF6 by means of X‐ray diffraction. The reaction equations are deduced according to the elements concentration gradient in cross section. The copper diffusion rate in liquid Al is calculated to be 1.13 × 10−12 m2/s by Fick's second law in semi‐infinite solid model, and the obtained conductivity is 1.758–1.767 × 10−2 Ω mm2/m. The results indicate that the interfacial bonding is in a good state and plating auxiliary KF aqueous solution. can significantly improve the substrate wettability. The appropriate hot‐dipping condition for the samples is 953–973 K for 4–8 s. Copyright © 2009 John Wiley & Sons, Ltd. 相似文献
104.
105.
106.
Yueping Fang Xiaogang Wen Shihe Yang 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2006,118(28):4771-4774
107.
Youhui Lin Can Xu Jinsong Ren Xiaogang Qu 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2012,124(50):12747-12751
108.
109.
Xinyi Cui Xiaogang Chu Zweigenbaum Jerry A. Yanyan Fang Wei Yong Yun Ling 《Chromatographia》2010,71(1-2):139-142
This study evaluated the screening of Sudan dyes in salty egg using liquid chromatography/time-of-flight mass spectrometry (LC–TOF-MS). With this technology, accurate mass measurements were made to generate elemental compositions of ions and to provide complementary structural information. This approach is useful for the elucidation of organic pollutants at trace levels in complex food extracts and in the present study salty egg samples were analyzed for the presence of Sudan IV. TOF accurate mass elemental composition data of Sudan IV were found to be crucial for structural elucidation which was applied to the investigation of nine salty egg samples.
相似文献110.
Sui X Xu Y Giovannelli JL Ho NT Ho C Yang D 《Angewandte Chemie (International ed. in English)》2005,44(32):5141-5144