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101.
This article presents an original work aimed at rationally designing molecularly imprinted polymer (MIP) toward a high specific adsorbent. Assembling with cobalt as the pivot, the MIP was prepared by coordinating polymerizable monomers around an inducible template. The use of pivot obviously plays a positive role on increasing the specificity of MIP, so as to adsorb more for the template and less for its analogue. Related studies indicate that these may be a result of increasing specific interaction, which makes the MIP capable of recognizing the imprint species. Further information from thermodynamic analysis reveals that the increasing specific interaction, in logic, can be due to a higher fidelity of imprint, which specifically allures the template to bind. 相似文献
102.
建立了气相色谱-质谱联用法定性和定量分析塑料中环己烷1,2-二甲酸二异壬酯(DINCH)的方法。考察了DINCH分子离子的质谱断裂过程,并建立了快速鉴定塑料中DINCH的理论方法。通过对不同溶剂提取效率的对比,采用二氯甲烷作为最佳提取溶剂。在优化条件下,该方法的线性范围为0.24~1.60 mg/L,相关系数为0.998,定量下限(S/N=10)为1.2 mg/kg。在加标水平为80~400 mg/kg时,4种不同塑料(PE、PP、PU、PVC)的回收率和相对标准偏差分别为82%~113%和1.1%~9.0%。将该方法用于实际塑料样品的检测,结果满意。 相似文献
103.
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105.
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
106.
Guo‐Ying Hong Zhong‐Xin Zhu Yuan‐Meng Duan Xuan Zhou Li‐Tai Jin 《Electrophoresis》2013,34(22-23):3171-3179
As a noncovalent fluorescence probe, in this study, salicylaldehyde azine (SA) was introduced as a sensitive fluorescence‐based dye for detecting proteins both in 1D and 2D polyacrylamide electrophoresis gels. Down to 0.2 ng of single protein band could be detected within 1 h, which is similar to that of glutaraldehyde‐silver stain, but approximately four times higher than that of SYPRO Ruby fluorescent stain. Furthermore, comparative analysis of the MS compatibility of SA stain with SYPRO Ruby stain indicated that SA stain is compatible with the downstream of protein identification by LC‐MS/MS. Additionally, the probable mechanism of the SA stain was investigated by molecular docking. The results demonstrated that the interaction between SA and protein was mainly contributed by hydrogen bonding and hydrophobic forces. 相似文献
107.
An alignment film derived from a photopolymerized self‐assembled film may be used to orient nematic liquid crystals after irradiating the film with linearly polarized UV (LPUV). A photosensitive cationic amphiphile was first synthesized containing two double bonds and which could be polymerized by UV. A layer‐by‐layer self‐assembled multilayer film was next prepared in an aqueous solution of the cationic amphiphile and poly(sodium 4‐styrenesulphonate); the UV‐Vis spectra showed that each layer of the LBL multilayer film was uniform. When the film was irradiated by LPUV, the photosensitive double bonds underwent [2+2] cycloaddition along the vector direction of LPUV. The polarized UV‐Vis absorption spectra also provided evidence that the film was anisotropic, i.e. the photopolymerization was along a certain direction. The anisotropic film was used as an alignment layer for nematic liquid crystals, and observations under a polarizing microscope indicated that the alignment of the liquid crystals was good, as expected, and that the orientation direction of the liquid crystals was always perpendicular to the electric vector of the irradiating LPUV. 相似文献
108.
酸碱解聚玉米秸秆分子结构的实验研究 总被引:1,自引:0,他引:1
以玉米秸秆为研究对象,分别采用5%H2SO4和5%NaOH溶液对秸秆进行解聚处理,并对解聚前后秸秆结构、化学组成、热稳定性等进行分析和表征。结果表明,与未处理前相比,经酸或碱解聚处理后,秸秆纤维结晶度由51.8%分别提高到63.5%和67.0%,秸秆中大部分半纤维素和部分木质素组分被脱除,半纤维素由29.10%分别降至7.02%和6.86%,木质素由38.12%分别降至32.21%和16.52%,而纤维素则由31.54%分别升至60.54%和76.15%。经酸碱处理后,秸秆表面形态结构变得疏松,出现小孔和裂缝,降解温度达到350℃,热稳定性能增加。上述结果说明,稀酸或稀碱均对玉米秸秆分子结构有一定程度的解聚作用,但就解聚溶出木质素而言,稀碱的解聚溶出效果要优于稀酸的。 相似文献
109.
Thien Y Vu Prof. Anna Chrostowska Prof. Thi Kieu Xuan Huynh Prof. Saïd Khayar Prof. Alain Dargelos Katarzyna Justyna Dr. Beata Pasternak Prof. Stanisław Leśniak Prof. Curt Wentrup 《Chemistry (Weinheim an der Bergstrasse, Germany)》2013,19(44):14983-14988
Thermal reactions of N‐benzylidene‐ and N‐(2‐pyridylmethylidene)‐tert‐butylamines ( 5 and 13 ) under FVT conditions have been investigated. Unexpectedly, at 800 °C, compound 5 yields 1,2‐dimethylindole and 3‐methylisoquinoline. In the reaction of 13 at 800 °C, 3‐methylimidazo[1,5‐a]pyridine was obtained as the major product. Mechanisms of these reactions have been proposed on the basis of DFT calculations. Furthermore, UV‐photoelectron spectroscopy combined with FVT has been applied for direct monitoring and characterization of the thermolysis products in situ. 相似文献
110.
Dr. Thien H. Ngo Dr. Hülya Berndt Dr. Michael Wilsdorf Prof. Dr. Hans‐Ulrich Reissig 《Chemistry (Weinheim an der Bergstrasse, Germany)》2013,19(45):15155-15165
The dipeptide isostere 5‐aminothiophene carboxylic acid has been combined with L ‐phenylalanine moieties to provide linear and cyclic hybrid oligopeptides. A suitable protecting group strategy and appropriate coupling methods have been developed to guarantee a high degree of enantiopurity of the resulting amides. Cyclic tetraamides have been efficiently obtained by macrocyclization of the linear derivatives. In the case of racemized cyclization precursors, two diastereomeric macrocycles (S,S/R,R and meso) have been isolated. Their crystal structures show clear effects of the stereogenic centers on the ring conformations and molecular packing. 相似文献