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731.
Cheng Ting Zhang Yuan Liu Xiaoyan Zhang Xiaoyu Zhang Haixia 《Mikrochimica acta》2017,184(10):4007-4013
Microchimica Acta - The authors describe a filter paper modified with mesoporous silica that carries phenylboronic acid on its surface. The material possesses the advantages of the flexibility of... 相似文献
732.
A highly selective HBT-based “turn-on” fluorescent probe for hydrazine detection and its application
Zhen Chen Xinxin Zhong Wangbo Qu Ting Shi Heng Liu Hanping He Xiuhua Zhang Shengfu Wang 《Tetrahedron letters》2017,58(26):2596-2601
As one of the important industrial chemicals, hydrazine (N2H4) can be inhaled through the skin, leading to many serious health issues. In this paper, we constructed a novel turn-on fluorescent probe HBTM for N2H4 detection based on ESIPT and ICT mechanism by incorporating the methyl dicyanvinyl group to 2-(2′-hydroxylphenyl) benzothiazole (HBT) fluorophore. The probe showed the following advantages: high sensitivity with detection limit of 2.9 × 10?7 M, high selectivity over other related interfering species, wide linear range of 0–140 μM and pH value adaptation. Moreover, the probe could detect N2H4 on paper strips and image N2H4 in living cells. 相似文献
733.
通过简单的一锅两步法制备了三氟金属(铝,钛,锆)接枝介孔SBA-15 (AlTf/S,TiTf/S,ZrTf/S)固体酸材料,并通过XRD,N2吸附,TGA,FTIR,原位吡啶FTIR和元素分析对这些材料进行了详细的表征.其中,ZrTf/S能够高效催化环氧化物温和条件下被胺或醇开环生成对应β-氨基醇或β-烷氧基醇,并且催化剂能循环利用.ZrTf/S相较于AlTf/S和TiTf/S酸性最强,因而催化活性也最高. 相似文献
734.
ChangMing Du Chao Shang Ting Wang ZiMing Li Xin Yang HaiTian Chen Ya Liu Kui Wang 《Plasma Chemistry and Plasma Processing》2017,37(1):77-97
An atmospheric microplasma jet system powered by an commercial transformer is developed for investigating the sterilizing efficiency of Escherichia coli in different conditions. The device can be hand-held and operated in the open air. The effect of carrier gas, gas flow rate, distance and treatment time of inactivation is studied. According to the experiment, plasma jet is able to inactivate all the bacteria on the surface in 20 s when the air flow rate is 5 L/min and the distance is 2.0 cm. Besides, the sterilization efficacy with different carrier gas follows an order as bellow: N2 > air > O2 > Ar. The measurements of malondialdehyde content, protein leakage quantity and Mg content are performed as well. In addition, the SEM after plasma treatment reveals that the integrity of E. coli cells is damaged and intracellular particles are excreted into the extracellular space. With discussions upon the mechanisms of surface sterilization, it is found that during the treatment of microplasma, it is mainly the etching actions of electrons and ions on the bacilli that kill the E. coli. Chemical effects rather than physical ones that are responsible for inactivation. Furthermore, the experiment results suggest that there may be better sterilization effect with gas mixture as carrier gas. 相似文献
735.
Shuai Zong Lan Li Jinglei Li Farnaz Shaikh Liu Yang Ming Ye 《Applied biochemistry and biotechnology》2017,182(2):669-686
In the present study, an intracellular melanin, named LIM205, was separated from Lachnum YM205 mycelia and was purified on a Sephadex G-15 column. The molecular weight of LIM205 was determined as 522 Da, and its molecular formula was speculated as C28H14N2O7S. The possible chemical structure of LIM205 was determined according to the results of Fourier transform infrared (FT-IR), 1H NMR, 13C NMR, and pyrolysis/GC-MS analysis. With the aim to increase its water solubility, its carboxymethylated derivative, named CLIM205, was formed by the substitution of hydrogen atoms in LIM205 with one, two, and three carboxymethylate groups. FT-IR, UV, and ESI-MS analysis demonstrated that the carboxymethylate groups were conjugated onto LIM205. The lead detoxification activities of LIM205 and CLIM205 had also been investigated. In vivo test showed that both LIM205 and CLIM205 reduced the tissue lead concentration, enhanced lead excretion, and reversed lead-induced alterations in superoxide dismutase (SOD), glutathione peroxidase (GSH-Px), and malondialdehyde (MDA) concentrations in mice, with CLIM205 showed better efficacy. The study indicates that LIM205 and CLIM205 have significant lead detoxification effect which will contribute to solve related problems. 相似文献
736.
737.
采用气相色谱法,建立了同时检测食品工业用大孔吸附树脂中的苯、1,2-二氯乙烷、甲苯、邻二甲苯、间二甲苯、对二甲苯、氯苯、苯乙烯、二乙烯苯、丙烯腈、甲基丙烯酸甲酯等11种有机残留物的方法。色谱柱为DB-WAX毛细柱,检测器为氢火焰离子化检测器,该方法的专属性强,在所考察的浓度范围内线性相关系数均在0.99以上,最低检出限为0.002~0.008μg/mL,样品加标回收率为72.4~104.7%,稳定性、精密度和重现性的RSD分别为1.68~5.26%、1.57~6.83%、2.91~9.62%。本方法具有简便易行、准确、稳定、快速等特点。 相似文献
738.
An ionic liquid (IL) EPReO4 (N‐ethylpyridinium rheniumate) was prepared. The density and surface tension values of the IL were determined in the temperature range of 293.15–343.15 K. The ionic volume and surface entropy of the IL were estimated by extrapolation, respectively. In terms of Glasser's theory, the standard molar entropy and lattice energy of the IL were estimated, respectively. Using Kabo's and Rebelo's methods, the molar enthalpy values of vaporization of the IL, ΔglH0m (298 K), at 298 K and, ΔglH0m (Tb), at hypothetical normal boiling point were estimated, respectively. According to the interstice model, the thermal expansion coefficient of IL EPReO4 (α) was calculated and compared with experimental value, finding their magnitude order is in good agreement by 8.98%. 相似文献
739.
通过静态吸附试验,研究了强碱性树脂IRA-400对富马酸的吸附性能。结果表明,该树脂与弱碱性树脂IRA-94相比,受pH值影响较小,在pH=3.5时,该树脂对富马酸具有较好的吸附性能,其静态饱和吸附容量为1.466mmol/g湿树脂;该树脂对富马酸的吸附等温线符合Freundlich等温方程,在298.15K,308.15K和318.15K下的相关系数R2均大于0.99,方程的特征参数n1,属"优惠吸附";吸附过程ΔG0,ΔS0,ΔH0,表明此反应过程是放热的,自发进行的,降低温度有利于吸附反应的发生;吸附动力学研究表明,IRA-400树脂对富马酸的吸附过程主要受液膜扩散控制。 相似文献
740.
<正>Two new eudesmane derivatives were isolated from the leaves and flowers of Verbesina virginica,along with the known 6-O-β-E -p-coumaroyl-4α-hydroxyeudesmane(1).Their structures were determined as 6-O-β-Z-p-coumaroyl-4α-hydroxyeudesmane(2) and 6-O-α-E-p-coumaroyl-1β-4α-dihydroxyeudesmane(3) by spectroscopic methods. 相似文献