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471.
Wei Xu Ping Liu Chunhui Guo Chao Dong Xiuhua Zhang Shengfu Wang 《Mikrochimica acta》2013,180(11-12):1005-1011
We describe a molecularly imprinted electrochemical sensor for selective and sensitive determination of β2-agonists. It is making use of a combination of single-wall carbon nanotubes (SWNTs) with a molecularly imprinted sol–gel. The SWNTs were introduced in order to enhance electron transport and sensitivity. The imprinted sol–gel film with its specific binding sites acts as a selective recognition element and as a preconcentrator for β2-agonists. The morphology of the imprinted film was characterized by scanning electron microscopy. The optimized sensor displays high sensitivity and excellent selectivity for the β2-agonists as shown for their determination in human serum samples. Figure
A molecularly imprinted electrochemical sensor was constructed for selective and sensitive determination of β2-agonists. The optimized sensor displays high sensitivity and excellent selectivity for the β2-agonists as shown for their determination in human serum samples. 相似文献
472.
The Vilsmeier reaction of nickel(II) chlorin P6 trimethyl ester with 3-dimethyl-aminoacrolein yielded nickel(II) chlorin P6 20-(2-formylvinyl) trimethyl ester and nickel(II) chlorin P6 3-(1-hydroxyethyl)-3-devinyl-20-(2-formylvinyl) trimethyl ester. Also, the outgrowths of nickel(II) chlorin P6 20-(2-formyl) trimethyl ester and nickel(II) chlorin P6 3-(2-formylvinyl)-3-devinyl-20-(2-formyl) trimethyl ester were obtained by Vilsmeier reaction with dimethylformamide. By treating the derivatives of nickel(II) 20-(2-formyl)-chlorin and nickel(II) 3-(2-formylvinyl)-20-(2-formyl)-chlorin with trifluoracetic acid, the removal of the central nickel(II) ion was accomplished. The derivatives of 20-(2-formyl)-chlorin and 3-(2-formylvinyl)-20-(2-formyl)-chlorin demonstrated considerable bathochromic shift of the major absorption band in the red region of the optical spectrum. 相似文献
473.
The chloromethylation of aromatic hydrocarbons proceeded efficiently using the reusable ionic liquid [emim]BF4 as promoter. The reactions were completed in 5 h at 70°C with good yields and easy workup. 相似文献
474.
A Stereoselective aldol reaction between bis(tert-butyldimethylsilyloxy) acetone and an isoxazoline-derived azaenolate is a key step in the construction of a C-ring model of sesbanimide A. 相似文献
475.
Shiliang He Hang Zhao Xiurong Guo Guang Xin Baozhan Huang Limei Ma Xinglong Zhou Rui Zhang Dan Du Xiaohua Wu Zhihua Xing Wen Huang Qianming Chen Yang He 《Tetrahedron》2013
J-AT nucleoside-based organogelators 1a and 1b were designed and synthesized. They were endowed with unparalleled superiority to natural nucleobase analogues 2–6 to gelate aromatic solvents due to their excellent self-assembly properties. The J-AT nucleoside-based organogelators showed a specific self-complementary base pair recognition characteristic. The gel stabilities of 1a and 1b were drastically influenced by adenine analogue 2, hardly affected by thymine analogue 3, uracil analogue 4, cytosine analogue 5, and mildly interrupted by guanine analogue 6. 相似文献
476.
Synthesis of 2-cinnamoyl-1-styryl-3,4-diarylcyclopentanol via cyclodimerization of 1,5-diaryl-1,4-pentadien-3-one mediated by zinc was carried out in good yields at room temperature in NH4Cl (aq.) and tetrahydrofuran under ultrasonic irradiation. In comparison with conventional methods, the main advantages of the present procedure are shorter reaction time and better yields. 相似文献
477.
478.
Yao Huang Long‐Jiang Liu Ming‐Shan Zhou Xiao‐Jun Zhou Chao Zhu Fei‐E Fu Yong‐Ming Zhang 《无机化学与普通化学杂志》2013,639(10):1884-1887
Two metal‐organic frameworks, [Zn(dmtrz)(btrc)1/3]n ( 1 ) and [Zn2(dmtrz)2(btec)(H2O)2]n ( 2 ) (dmtrz = 3, 5‐dimethyl‐1‐H‐1, 2,4‐triazole, btrc = 1, 3,5‐benzenetricarboxylate, btec = 1, 2,4, 5‐benzenetetracarboxylate), were synthesized by hydrothermal reaction. The crystal structure analysis reveals that compound 1 is a dense 3D framework with Schläfli symbols of {43}2{46 · 66 · 83}3, which is a loh1 structure. Compound 2 is a 2D network. In addition, the photoluminescence of two compounds were studied in solid state at room temperature, together with their thermal analysis. 相似文献
479.
Xiaofeng Wang Weiyi Xing Gang Tang Ningning Hong Weizhao Hu Jing Zhan Lei Song Wei Yang Yuan Hu 《Polymer Degradation and Stability》2013
A novel sulfur-bearing secondary antioxidant with a high molecular weight of 2252 (OS-POSS), successfully synthesized via photoinitiated thiol-ene click reaction, was compared with two commercial sulfur-bearing secondary antioxidants on the stabilization of polypropylene (PP). The results of their oxidation induction time (OIT) via differential scanning calorimeter measurement (DSC) showed that the higher the molecular weight of secondary antioxidant is, the longer the OIT value, whether such sulfur-bearing antioxidant is used singly or in combination with primary antioxidant. The study of their long-term accelerated thermal aging in the air oven at 150 °C displayed that the molecular structure of sulfur-bearing secondary antioxidant, besides molecular weight, is another highly important factor determining the antioxidant efficiency, i.e., physical loss of antioxidants with the relatively low molecular weight may determine antioxidant efficiency, whereas thioether groups having neighboring ester carbonyl moieties may decompose more hydroperoxides with quicker rate. 相似文献
480.
Mao Chen Ting Zhao Zhong‐Xin Zhu Chao Niu Dan‐dan Ruan Mao‐Wei Ni Xuan Zhou Li‐Tai Jin 《Electrophoresis》2013,34(24):3277-3286
An improved Stains‐All (ISA) staining method for phosphoproteins in SDS‐PAGE was described. Down to 0.5–1 ng phosphoproteins (α‐casein, β‐casein, or phosvitin) can be successfully selectively detected by ISA stain, which is approximately 120‐fold higher than that of original Stains‐All stain, but is similar to that of commonly used Pro‐Q Diamond stain. Furthermore, unlike the original Stains‐All protocol that was time consuming and light unstable, ISA stain could be completed within 60 min without resorting to protect the gels from light during the whole staining procedure. According to the results, it is concluded that ISA stain is a rapid, sensitive, specific, and economic staining method for a broad application to the research of phosphoproteins. 相似文献