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111.
112.
A new protein molecularly imprinted polymer (MIP) was prepared with grafting polyvinyl alcohol as assistant recognition polymer chains (ARPCs). The ARPCs and acrylamide monomers were interpenetrated and then polymerized on the surface of macroporous acrylate adsorbent spheres. The template BSA was removed by treatment with 2.00 mol L-1 potassium chloride (KCl) solution and the adsorbed proteins were detected with sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE). 0.150, 0.500, and 2.00 mo... 相似文献
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The entire gene of carboxyltransferase(CT) domain of acetyl-CoA carboxylase(ACCase) from Chinese Spring wheat(CSW) plastid was cloned firstly, and the 2.3 kb gene was inserted into PET28a^+ vector and expressed in E. coil in a soluble state. The (His)6 fusion protein was identified by SDS-PAGE and Western blot. The recombinant protein was purified by affinity chromatography, and the calculated molecular mass(Mr) was 88000. The results of the sequence analysis indicate that the cloned gene(GeneBank accession No. EU124675) was a supplement and revision of the reported ACCase CT partial cDNA from Chinese Spring wheat plastid. The recombinant protein will be significant for us to investigate the recognizing mechanism between ACCase and herbicides, and further to screen new herbicides. 相似文献
116.
Rui Liu Jing-fu Liu Xiao-xia Zhou Gui-bin Jiang Rui Liu 《Trends in analytical chemistry : TRAC》2011,30(9):1462-1476
Raman-based technologies have proved to be excellent tools for on-site and in-vivo analysis, due to the non-invasive nature of their detection, their capability of providing structure information, their high tolerance to aqueous samples, the ultra-sensitivity of surface-enhanced Raman scattering (SERS) and resonance Raman scattering (RRS), the high spatial resolution of tip-enhanced Raman scattering (TERS), and the ultrashort spectra-acquisition time for coherent anti-Stokes Raman scattering (CARS) and stimulated Raman scattering (SRS).In this review, we highlight the recent success of Raman-based technologies in various applications, including:
(1)
on-site surface analysis and chemical-reaction monitoring; (2)
on-site identification of cultural objects, archeological studies and planetary science; (3)
in-vivo analysis of cells and microorganisms; (4)
in-vivo diagnosis inside human and animal bodies; (5)
in-vivo fast Raman imaging and mapping; (6)
the study of SERS processes; and, (7)
assessment of nanomaterial safety.
117.
An efficient preparation of (±)-antofine is described. The main steps involved in this synthesis are the Horner–Wadsworth–Emmons reaction, the intramolecular Schmidt reaction of an azido aldehyde, and the one-pot deprotection of the N-formyl group, followed by Pictet–Spengler cyclization. The asymmetric hydrogenation of the trisubstituted α,β-unsaturated ester is also explored, however only moderate enantio-control (55% ee) is obtained. Finally, (±)-antofine is prepared in six steps from the phenanthryl aldehyde 5 with an overall yield of 35%. 相似文献
118.
Activity coefficients of potassium bromide in aqueous mixtures of potassium bromide and lithium bromide were determined by emf measurement at 25°C and at six ionic strengths from 0.1 to 2.5 mol·kg-1. The experimental data were fitted using the Scatchard–Rush–Johnson and Pitzer models. The osmotic coefficients, excess Gibbs energies of mixing, and activity coefficients of lithium bromide in aqueous mixtures were calculated using Pitzer mixing parameters obtained in this work. 相似文献
119.
碘化钾-乙基紫-水体系固相浮选分离镉的研究 总被引:4,自引:0,他引:4
研究了碘化钾 乙基紫 水体系固相浮选分离镉的行为及与常见金属离子分离的最佳条件。试验表明,将碘化钾溶液、乙基紫溶液和盐酸溶液混合稀释,生成稳定的CdI2-4·(EV+)2三元缔合物可很快浮于水相,使Cd(Ⅱ)被定量浮选。控制适当条件,可实现Cd(Ⅱ)与常见金属离子Mn(Ⅱ)、Al(Ⅲ)、Ni(Ⅱ)、Zn(Ⅱ)之间的分离。对合成水样进行了浮选分离测定,结果满意。 相似文献
120.
物理老化无规聚苯乙烯屈服机理的研究 总被引:3,自引:0,他引:3
利用机械拉伸、示差扫描量热(DSC)以及溶剂溶胀等方法研究了物理老化后的无规聚苯乙烯(α-PS)的应力屈服行为,并从凝聚缠结的观点对实验结果进行了解释.实验结果表明,经物理老化后的α-PS在拉伸过程中出现应力屈服峰实质上是逐步打开凝聚缠结的过程.凝聚缠结是聚合物非晶相在物理老化过程中相邻的两三条链的局部链段由于范德华吸引力的作用形成的一种有序结构,其作用能很弱,升温至Tg附近,机械拉伸至屈服点以及溶胀剂都可将其完全破坏. 相似文献