Di-ionizable p-tert-butylcalix[4]arene-1,2-crown-3 ligands in cone and 1,2-alternate conformations: synthesis and metal ion extraction

Novel di-ionizable p-tert-butylcalix[4]arene-1,2-crown-3 ligands in cone and 1,2-alternate conformations were prepared as potential metal ion extractants. Selective bridging of proximal hydroxyl groups of the calix[4]arene platform by a crown-3 polyether unit was achieved under Mitsunobu reaction conditions. In addition to the carboxylic acid group, the acidity tunable N-(X)sulfonyl oxyacetamide functions [OCH(2)C(O)NHSO(2)X] with X group variation from methyl to phenyl to p-nitrophenyl to trifluomethyl were used as the proton-ionizable groups. Conformations and regioselectivities of the new ligands were established by (1)H and (13)C NMR spectroscopy. Competitive solvent extractions of alkali metal cations and of alkaline earth metal cations from aqueous solutions into chloroform were performed, as were single species extractions of lead(ii) and mercury(ii).     

Synthesis, structure, and luminescent and magnetic properties of novel lanthanide metal-organic frameworks with zeolite-like topology

A series of microporous lanthanide metal-organic frameworks [Ln(BTC)(DMF)(2) x H(2)O, Ln = Tb (1), Dy (2), Ho (3), Er (4), Tm (5), Yb (6); DMF = N,N'-dimethylformamide] with 4 x 4 x 4 x 6 x 6 x 8 topology, which is very common in the zeolite topologies, have been synthesized under mild conditions. The single-crystal X-ray diffraction analysis reveals that they exhibit the same three-dimensional (3D) architecture and crystallize in monoclinic symmetry space group C2/c. Organic and inorganic four-connected nodes link each other to form a 3D open framework. The framework contains approximate 13 Angstrom x 7 Angstrom rectangle channels along the [1,1,0] and [1,-1,0] directions, respectively. The luminescent properties of these complexes have been studied, and complex 1 shows a Tb(3+) characteristic emission in the range of 450-650 nm at room temperature. Complexes 1-5 exhibit antiferromagnetic interaction between Ln(3+) ions. The water sorption isotherm shows that about 15 water molecules per unit cell can be adsorbed into the micropores of dehydrated complex 4.     

用计算机模拟γ射线无损检测物理实验

本简单介绍用计算机模拟γ射线无损检测物理实验教学软件。     

定义在分形集上函数的H-导数

 分形的生成含有降维与升维两种形式,采用适当的方式总可以对分形集加以定向化,分形的内禀测度是Hausdorff测度。因此,定义在分形集上的函数可以看作是在Hausdorff测度下定义在区间[0, h]。在函数图像也是分形的前提下,依函数的Hausdorff测度的定义,给出了定义在分形集上的函数f(p)关于Hausdorff测度p的导数以及一些性质。     

基于准等重二甲基化标记的高通量蛋白质组选择性交叉标记装置

面对生物学及精准医学等领域多变量、大样本量的蛋白质组定量分析的需求,高通量的定量标记及分析已经成为近年来蛋白质组学方法发展的趋势。发展了一种基于准等重二甲基化标记策略的高通量肽段末端选择性交叉标记装置（pIDL-StageTip）,借助简单的装置及离心力,有效地增加了定量标记的通量,并保证了肽段末端两步标记反应时间的可控性及操作的简便性。通过优化酸性条件下NaBD₃CN与NaBH₃CN体系的标记条件,得到了标准蛋白质酶解产物100%的标记效率、95%以上的标记选择性;在人源蛋白质组复杂体系下,标记效率大于99%,标记选择性为100%。基于该装置的定量方法具有很高的定量准确度及精密度。该装置为实现高可操作性、高准确度、高通量的蛋白质组定量标记提供了一个可靠的解决方案。     

Synergistic film-forming effect of oligo(ethylene oxide)-functionalized trimethoxysilane and propylene carbonate electrolytes on graphite anode

Oligo(ethylene oxide)-functionalized trialkoxysilanes can be used as novel electrolytes for high-voltage cathode, such as LiCoO₂ (4.35 V) and Li_1.2Ni_0.2Mn_0.6O₂ (4.6 V); however, they are not well compatible with graphite anode. In this study, a synergistic solid electrolyte interphase (SEI) film-forming effect between [3-[2-(2-methoxyethoxy)ethoxy]propyl]-trimethoxysilane (TMSM2) and propylene carbonate (PC) on graphite electrode was investigated. Excellent SEI film-forming capability and cycling performance was observed in graphite/Li cells using the electrolyte of 1 M LiPF₆ in the binary solvent of TMSM2 and PC, with the PC content in the range of 10–30 vol.%. Meanwhile, the graphite/Li cells delivered higher specific capacity and better capacity retention in the electrolyte of 1 M LiPF₆ in TMSM2 and PC (TMSM2:PC = 9:1, by vol.), compared with those in the electrolyte of 1 M LiPF₆ in TMSM2 and EC (TMSM2:EC = 9:1, by vol.). The synergistic SEI film-forming properties of TMSM2 and PC on the surface of graphite anode was characterized by electrolyte solution structure analysis through Raman spectroscopy and surface analysis detected by scanning electron microscopy (SEM), energy dispersive spectroscopy (EDS), and Fourier transform infrared spectroscopy (FT-IR) analysis.     

Aqueous germanate solution,alternative sol–gel precursor for preparation of Mn<Subscript><Emphasis Type="Italic">x</Emphasis></Subscript>Ge<Subscript>1−<Emphasis Type="Italic">x</Emphasis></Subscript> diluted magnetic semiconductors

The solids content and gelation time of aqueous germanate solution were examined in this work. Samples of 5, 10 and 20 mol% Mn doped Ge were prepared by using the aqueous germanate solution as a liquid Ge precursor. No second phase such as Mn₅Ge₃ was detected in the 5 and 10 mol% Mn doped samples, implying that Mn ions were uniformly diluted into the Ge host matrix. The 5 and 10 mol% Mn-doped Ge samples exhibit room-temperature ferromagnetic behaviors that are likely originated from the RKKY (Ruderman–Kittel–Kasuya–Yosida)-like interaction between the localized Mn ions in the Ge matrix. Therefore, the aqueous germanate solution can be an alternative sol–gel precursor for preparation of the Mn _x Ge_1−x diluted magnetic semiconductors (DMSs).     

Analysis of multiplex PCR fragments with PMMA microchip

Microchip electrophoresis is a promising technique for analysis of bio-molecules. It has the advantages of fast analysis, high sensitivity, high resolution and low-cost of samples. Plastic chip has the potential of mass production for clinical use for its advantages in biocompatibility and low cost. In this work, the method for fabrication of poly(methyl methacrylate) (PMMA) chip was described, and conditions for DNA separation were investigated with the chip. The PMMA microchip was used for detection of multiplex PCR products of 18 and 36 cases with SARS and hepatitis B virus infection under optimized separation conditions. Microchip electrophoresis showed higher sensitivity, higher resolution and less time consumption when compared with gel electrophoresis. The microchip electrophoresis with PMMA chip provided a rapid, sensitive and reliable method for analysis of multiplex PCR products.     

Stereoselective hydroxycarbonylation of vinyl bromides to alpha,beta-unsaturated carboxylic acids in the ionic liquid [BMIM]PF6

(E/Z)-isomers containing vinyl bromides were stereoselectively carbonylated to the corresponding (E)-alpha,beta-ethylenic carboxylic acids in the ionic liquid [BMIM]PF6. Vinyl dibromides also underwent hydroxycarbonylation to give monoacids. The products are pure by proton NMR spectroscopic determination without purification by silica gel column chromatography or recrystallization.     

关于混合模式色谱固定相对蛋白保留特征的研究

为使混合机理色谱(MMC)得到广泛地应用, 合成、表征和评价MMC固定相就成了首先要解决的问题. 依据离子交换色谱柱也具有疏水色谱(HIC)保留机理的特征, 选了4种弱阳离子交换(WCX)柱和一根二维[2D(WCX,HIC)]色谱柱, 研究了标准蛋白在这两类色谱柱上的保留行为. 这四种WCX色谱柱中的两种能在WCX和HIC两种分离模式下分离蛋白, 虽不如2D色谱柱效果好, 但有可能当成“准2D柱”来使用. 发现蛋白在这四种WCX柱上所显示的HIC分离特征各不相同, 且保留值随盐浓度变化呈现出的“U型”曲线也有大的差异. 实验结果显示, “U型”曲线的宽度和临界点分别与色谱动力学和热力学因素相关. 还对这两类色谱固定相的峰容量表征方法和命名提出了建议和说明.