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991.
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   
992.
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   
993.
A kind of emulsifier-free latex (FL) was successfully synthesized from styrene (St) and butyl acrylate (BA) with 2-acrylamido-2-methyl propane sulfonic acid (AMPS) as a reactive emulsifier. The particle size of latex particles, stability against electrolytes, minimum film forming temperature (MFT) and water contact angle (CA) were evaluated and compared with a conventional latex (CL). Test results show that FL has larger particle size, better stability against electrolytes and lower MFT value compared with CL; higher AMPS content leads to smaller particle size and smaller water CA.  相似文献   
994.
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   
995.
A general molecular mechanics (MM) model for treating aqueous Cu2+ and Zn2+ ions was developed based on valence bond (VB) theory and incorporated into the atomic multipole optimized energetics for biomolecular applications (AMOEBA) polarizable force field. Parameters were obtained by fitting MM energies to that computed by ab initio methods for gas‐phase tetra‐ and hexa‐aqua metal complexes. Molecular dynamics (MD) simulations using the proposed AMOEBA‐VB model were performed for each transition metal ion in aqueous solution, and solvent coordination was evaluated. Results show that the AMOEBA‐VB model generates the correct square‐planar geometry for gas‐phase tetra‐aqua Cu2+ complex and improves the accuracy of MM model energetics for a number of ligation geometries when compared to quantum mechanical (QM) computations. On the other hand, both AMOEBA and AMOEBA‐VB generate results for Zn2+–water complexes in good agreement with QM calculations. Analyses of the MD trajectories revealed a six‐coordination first solvation shell for both Cu2+ and Zn2+ ions in aqueous solution, with ligation geometries falling in the range reported by previous studies. © 2012 Wiley Periodicals, Inc.  相似文献   
996.
NaOH/poly(sodium acrylate) composites were prepared by in situ polymerization of acrylic acid with an overneutralization level by adding excess NaOH. The composites were studied by XRD, IR and 23Na MAS NMR spectroscopy. The results showed that the high neutralization degree (>100%) may lead to a complete polymerization. Both XRD and 23Na MAS NMR spectra did not show any peaks of phase-separated NaOH or Na2CO3 until the neutralization degree was up to 217.5%. It can be presumed that the aggregates of Na+ ions can contain approximately two Na+ units for every carboxyl group before the phase separation.  相似文献   
997.
Two kinds of topical dosage forms of hinokitiol (HKL), namely vesicles and oil‐in‐water (O/W) emulsions, were prepared. Behenyl trimethylammonium chloride (BTMAC) and fatty acids were used as bilayer‐forming materials of the vesicles, and oils were employed as oil phases of the emulsions. The substantivity of HKL in the preparations was evaluated in vitro using hairless mouse skins. After applying the preparations onto the skin and rinsing it, the amount of HKL left on the skin was determined using high performance liquid chromatography (HPLC). It was higher when HKL was encapsulated in cationic vesicles rather than in nonionic vehicles, emulsions. An ionic interaction between the cationic vehicle and negatively charged skin is likely to account for the high substantivity. Among the emulsion preparations, an emulsion having octyl salicylate as oil phase exhibited the highest substantivity of HKL. This is probably because that the oil is a good solvent for HKL and it is skin‐retentive. In vivo hair growth‐promotion effect of each dosage form was investigated, where the sample application onto the clipped backs of female mice (C57BL6) and the subsequent rinsing of the backs were done once a day for 30 days. Only HKL in the cationic vesicles had hair growth promotion effect, possibly due to the significant substantivity.  相似文献   
998.
A stable superhydrophobic surface have been fabricated with poly(furfuryl alcohol) (PFA)/polytetrafluoroethylene (PTFE) composite coatings on steel substrates by using a facile method. The observation of field emission scanning electron microscopy revealed that the hierarchical microstructures formed on the surfaces are controlled by varying the curing temperature. This method can be easily operated on substrates of steel, therefore is readily developed to other engineering metal substrates such as aluminum, copper, etc.  相似文献   
999.
唐爱玲  瞿建国 《分析化学》2013,(7):1091-1096
在中分辨模式(m/Δm=4000)下,利用扇形磁场电感耦合等离子体质谱仪(SF-ICP-MS)建立了精确测定硫同位素组成的方法,对ICP离子源、光学透镜系统、数据获取参数(扫描时间、扫描次数、积分窗口等)以及浓度效应进行了系统优化和评估,并用"标准-样品"交叉法校正仪器自身的质量歧视。在此基础上,在不同日期重复测定了GBW04414和GBW04415硫同位素参考物质的δ34SV-CDT,分别为"0.01‰±0.31‰和22.15‰±0.42‰,误差<±0.06‰,精密度<±0.5‰(n=10),达到了目前同类方法所报道的最高水平。同时,对瓶装矿泉水、雨水和河水等天然水样中δ34S进行了测定,测定精密度为±0.19‰~±0.58‰,与同位素参考物质的测定精密度相近。因此,本方法可用于精确测定天然水样中S同位素组成。  相似文献   
1000.
采用修饰与未修饰单壁碳纳米管固定C-C键水解酶BphD,并对固定化酶的相对活性、稳定性、重复使用性进行了考察.结果表明,未修饰单壁碳纳米管固定的BphD相对活性为游离态的52.5%,其热稳定性和在变性剂中的稳定性均有所提高,且重复使用10次仍可保持初始活力的90%.修饰单壁碳纳米管固定的BphD相对活性可达99.7%,但其稳定性没有明显提高.同源模建及分子对接分析结果显示,未修饰的单壁碳纳米管对BphD亚基之间的联系可能存在干扰作用,从而对其活性产生影响.  相似文献   
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