Heterogeneity in optimized solid-state synthesis of metavanadate AVO3 (A = Rb,Cs)

Research on Chemical Intermediates - Methanol was used to optimize the solid-state synthesizing method of alkali metavanadates AVO3 (A = Rb, Cs) for the first time and the...     

Binary oppositely charged polyelectrolyte brushes for highly selective electroless deposition of bimetallic patterns

Binary polymer brushes consisting of two oppositely charged polyelectrolytes are grafted on one substrate via two-step surface-initiated atomic transfer radical polymerization from contact printed initiator monolayer. The polymeric structures provide robust and effective platforms for highly selective loadings of catalytic-active ionic moieties with opposite charges [PdCl₄^2? and Pd(NH₃)₄²⁺] that can be used for electroless deposition (ELD) of metals in the subsequent steps. Binary metallic Cu/Ni patterns can thus be built up with high site-selectivity when the deposition was carried out in the order of Cu and Ni.     

Electrodeposition of CuInSe2 films by an alternating double-potentiostatic method using nearly neutral electrolytes

One step electrodeposition with an alternating double-potentiostatic(DPSED) program was used to prepare CuInSe₂ thin films in nearly neutral aqueous electrolytes with sodium citrate complex. Linear sweep voltammetry(LSV) was measured to probe voltammetric properties of electrolytes with respect to Cu, In and Se individual precursor and their mixed solutions. Compositional and structural characteristics of the as-deposited and annealed films at 400 °C in Ar atmosphere for 0.5 h were analyzed by XRD and XPS. The results showed that reduction of Cu²⁺ to Cu⁺ at one potential point of ?800 mV and subsequently formation of CuIn alloy as well as metal In and amorphous Se at the other potential point of ?1400 mV were responsible for synthesis of CISe chalcopyrite. Composition self-regulation made DPSED films have three elements co-deposition and more uniform element distribution, which promoted chalcopyrite CISe formation.     

Square wave voltammetry assay of organophosphorus inhibition on cholinesterase in two phases of isooctane/water

A novel method for the detection of pesticides by inhibition of cholinesterase (ChE) from earthworm was developed. Two immiscible phases are employed where the organic phase isooctane contains substrate and the aqueous phase does enzyme. Water insoluble indophenol acetate was hydrolyzed by ChE at the interface of two phases to produce water soluble indophenol. The latter spontaneously penetrates into aqueous solution and gives the change of electrochemical signal. Organophosphorus compounds methyl parathion dissolved in isooctane phase could inhibit the activity of ChE at the interface of two phases and a corresponding inhibition relationship is given in the concentration range of 50 ng/ml–100 μg/ml.     

铁配合物的环境光化学及其参与的环境化学过程

铁是地壳中含量最为丰富的金属元素之一,而自然界中存在的绝大多数溶解性铁都是以有机络合形式存在的。环境中的铁配合物在光照下会发生直接光解和次级的(光)化学反应过程,生成还原性的Fe(Ⅱ)和有机自由基以及衍生的活性氧物种。铁配合物的环境光化学反应将深刻影响着氧自由基的生成与衰减、有机物降解和其他元素的环境化学循环过程,因此,成为近年来国际环境科学领域的研究热点。本文介绍了铁配合物光还原反应的类型和原理,分析了Fe(Ⅱ)(光)化学氧化的可能机理和影响因素,并对国内外关于铁参与的环境化学过程所开展的研究进行了评述。在此基础上,通过分析目前研究中所存在的问题,对今后的研究方向和趋势作了展望。     

Biofunctional magnetic nanoparticles as contrast agents for magnetic resonance imaging of pancreas cancer

We report on the fabrication and characterization of biofunctional magnetic nanoparticles as contrast agents for magnetic resonance imaging. The anti-cancer antigen 19-9 monoclonal antibody (a cancer-targeting antibody) was conjugated onto the magnetic contrast agents in an effort to detect pancreatic tumor. The structure, size, morphology and magnetic property of the biofunctional magnetic nanoparticles are characterized systematically by means of transmission electron microscopy and X-ray diffractometry. Furthermore, the interaction between the nanoparticles and pancreas cancers cells are investigated by atomic force microscope and transmission electron microscopy. Magnetic resonance imaging demonstrates that the conjugated nanoparticles can effectively target cancer cells both in vitro and in vivo, suggesting that they potentially can be used as contrast agents for magnetic resonance imaging of pancreas cancer.     

Complex formation of cinnamaldehyde-methyl-β-cyclodextrin and muscone-methyl-β-cyclodextrin by supercritical carbon dioxide processing and sealed heating method

Firstly, the interaction between cinnamaldehyde (CIN) and methyl-β- cyclodextrin (MBCD) was studied in aqueous solution. 1:1 inclusion complex was formed and the association constant was 187 ± 9 M^?1. Then the complex of CIN–MBCD and muscone–MBCD was prepared both by sealed heating method and by supercritical carbon dioxide (sc CO₂) approach. Complete complex was obtained by both methods for CIN–MBCD. Some CIN molecules was weakly associated with MBCD molecules in products by sealed heating method, all CIN molecules was strongly associated with MBCD molecules in products by sc CO₂ processing. Complete complex between muscone and MBCD was not obtained. The choice for the size of guest molecule still existed for MBCD cavity in sealed heating method and sc CO₂ processing.