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931.
A novel, convenient, efficient, three‐step, one‐pot synthesis of 2‐oxazolidinones from phenyl 2‐hydroxyalkyl selenides was developed. Using this methodology, 2‐oxazolidinones are obtained in good yields (76–85%) by reaction of phenyl 2‐hydroxyalkyl selenides with benzoyl isocyanate and subsequent oxidation/cyclization, followed by hydrolysis with hydrochloric acid solution. 相似文献
932.
A series of heterometallic LnIII–SbIII edta‐containing compounds with the formulas [Sb2(edta)2Ln]NO3 · nH2O [edta = ethylenediaminetetraacetate; Ln = Eu, n = 7 ( 1 ); Gd, n = 7.5 ( 2 ) and Tb, n = 8 ( 3 )] were synthesized and characterized by elemental analyses (EA), powder X‐ray diffraction (PXDP), Fourier transform infrared spectroscopy (FT‐IR), and thermogravimetric analyses (TGA). Their fluorescence and magnetic properties were also studied. The thermal analysis demonstrates the compounds formation of the antimony, lanthanide ions, and edta4– ligands. FT‐IR spectra reveal that the antimony and lanthanide ions are connected through the carboxylate bridges. The studies of luminescence properties show that compounds 1 and 3 exhibit typical luminescence in the visible region. Furthermore, magnetic properties reveal compounds 2 and 3 have weak ferromagnetic behavior. 相似文献
933.
Mingming Zou Ying Li Jun Wang Qi Wang Yumei Kong Jingqun Gao Ping Fan 《Journal of solution chemistry》2013,42(4):849-865
The interaction between bovine serum albumin (BSA) and FeIII complexes with three binary organic acid (biorga) ligands, [FeIII(oxa)(H2O)4]+ (oxa = oxalic acid), [FeIII(pra)(H2O)4]+ (pra = propanedioic acid) and [FeIII(sua)(H2O)4]+ (sua = succinic acid), as well as the sonocatalytic damage of BSA in the presence of these three FeIII–biorga complexes under ultrasonic irradiation, were studied by UV–vis and fluorescence spectra. The experimental results show that the fluorescence quenching process of BSA caused by three FeIII–biorga complexes are all static quenching and the corresponding quenching rate constants (K q), equilibrium constants (K A) and the binding site numbers (n) were calculated. The results reveal that, under ultrasonic irradiation, the BSA molecules were obviously damaged by these FeIII–biorga complexes. In addition, the effects of several factors on the damage of BSA molecules were examined. The experimental results demonstrate that the damage degree of BSA increased with an increase of ultrasonic irradiation time, FeIII–biorga complex concentration, and ionic strength. In comparison, [FeIII(pra)(H2O)4]+ exhibited higher sonocatalytic activity than [FeIII(oxa)(H2O)4]+ and [FeIII(sua)(H2O)4]+. Finally, the extent of generation of $ \cdot {\text{O}}_{2}^{ - } $ · O 2 ? and ·OH during sonocatalytic processes was estimated. Perhaps, the results will be significant for promoting sonodynamic treatment (SDT) of tumors at the molecular level. 相似文献
934.
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
935.
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
936.
Jianqiang Zhang Jijiang Ge Anzhou Feng Ping Jiang Ruidong Li 《Journal of Dispersion Science and Technology》2013,34(11):1589-1595
To solve the problem of high pressure of water injection in low permeability reservoirs, a high concentration of surfactant system was developed in this article. With the solubilization of oil in aqueous surfactant solution as a criterion, a formula was screened from anionic and nonionic-anionic surfactants, and the optimal depressurized system was obtained as follows, 13.3% surfactant HEX +2.23% n-propanol +4.47% n-butanol, the solubilization capability being up to 0.66 g/g. This system had good salt tolerance, and it exhibited water external microemulsion in the range of of 1 to 200 g/L NaCl. Core flooding results show that this high concentration of surfactant system formed water external microemulsion with the residual oil in the core, reducing the displacement pressure over 35%. Meanwhile, the effects of concentration and injection volume on depressurization were also investigated. It is indicated that a good depressurization effect was achieved after injecting 1 pore volume of the system with the salt concentration of 100 g/L. 相似文献
937.
Wenyu Tian Chun Li Xiaoyu Liu Luhua Wang Zhong Zheng Xiangyun Wang Chunli Liu 《Journal of Radioanalytical and Nuclear Chemistry》2013,295(2):1423-1430
The diffusion of 125I? in compacted Gaomiaozi (GMZ) bentonite was investigated by capillary in-diffusion method. Apparent and effective diffusion coefficients and accessible porosity of iodide in GMZ bentonite were obtained, and the effect of ionic strength on diffusion parameters was studied. The apparent diffusion coefficients of iodide in compacted GMZ bentonite are in the range of 1.0–6.0 × 10?10 m2 s?1 under the conditions of dry bulk density 1,500 kg m?3 and temperature 298 K, and increase with increasing ionic strength. This effect was explained through the analysis of microscopic structure of compacted bentonite. The iodide can only diffuse in unbound interparticle pore solution of compacted bentonite. The apparent diffusion coefficient is a function of accessible porosity which is decided by the thickness of diffusion double layer, and the thickness is in turn controlled by ionic strength. 相似文献
938.
Jingtao Dai Pingping Yao Nanping Hua Ping Yang 《Journal of Dispersion Science and Technology》2013,34(6):872-875
Poly(N‐vinyl‐2‐pyrolidone) protected Pt‐core bimetallic Pt/Au‐shell (Pt@Pt/Au) nanoparticles were prepared by multi‐step reduction of HAuCl4 and H2PtCl6 alternately by hydrogen adsorbed on platinum atom. Transmission electronic microscopy (TEM) and x‐ray diffraction (XRD) were used to characterize Pt@Pt/Au nanoparticles. The structure of the shell of the nanoparticles seems to be the Au‐Pt solid solution. 相似文献
939.
Genxiang Luo Chunsheng Liu Qingdao Wang Wang Hao Ping 《Journal of Dispersion Science and Technology》2013,34(4):543-546
A simple formula for calculating the degree of counterion binding of dressed micelles is presented. This approximate expression for the spherical micelle is derived from the extending Langmuir's method in the case of high surface potentials. It works quite well for the estimation of the degree of counterion binding of micelles. The simple form is very convenient for practical use. 相似文献
940.
Shouzhu Li Yan Ma Xiuli Yue Zhong Cao Shaoqin Liu 《Journal of Dispersion Science and Technology》2013,34(12):1727-1731
A one-pot strategy for the fabrication of the quantum dots loaded cerasome has been successfully developed based on the condensation of dihexadecylamine and 3-isocyanatopropyltriethoxysilane, followed by spontaneous encapsulation and solubilization of hydrophobic quantum dots into the hybrid liposomal cerasomes in combination of self-assembly and sol-gel process. Fourier transform infrared spectroscopy and mass spectra prove the formation of the intermediate organoalkoxysilane with a lipid-like structure, which forms cerasome vesicles. After encapsulation into cerasome, quantum dots become well dispersed in aqueous solution. Such water-soluble QD cerasomes exhibit a better photostability and retain the luminescence property of the original hydrophobic quantum dots. 相似文献