Synthesis of inorganic-organic hybrids by incorporation of inorganic components into organic polymer using metal alkoxides

Inorganic-organic hybrids have been synthesized by incorporation of the inorganic component of Ti(OC₂H₅)₄ into the organic polymer of ethyl cellulose. The inorganic-organic hybrids did not dissolve in toluene used as a solvent for the starting materials. The ethanol was formed as a by-product of the alcoholysis condensation reaction between Ti(OC₂H₅)₄ and ethyl cellulose. These results suggest that ethoxy groups of Ti(OC₂H₅)₄ react with hydroxy groups of ethyl cellulose to form cross-linking bonds of –O–Ti–O–. The reaction of Ti(OC₂H₅)₄ with ethyl cellulose was further investigated by Fourier transform infrared (FT-IR) spectroscopy. The FT-IR spectroscopic experiments revealed that the Ti–O bond state of Ti(OC₂H₅)₄ was changed by refluxing a toluene solution of Ti(OC₂H₅)₄ with ethyl cellulose. The inorganic-organic hybrids have an interesting dielectric property; their dielectric constant is higher than that of ethyl cellulose and that of a simple mixture of TiO₂ and ethyl cellulose.     

High-productivity continuous biofilm reactor for butanol production

Corn steep liquor (CSL), a byproduct of the corn wet-milling process, was used in an immobilized cell continuous biofilm reactor to replace the expensive P2 medium ingredients. The use of CSL resulted in the production of 6.29 g/L of total acetone-butanol-ethanol (ABE) as compared with 6.86 g/L in a control experiment. These studies were performed at a dilution rate of 0.32 h⁻¹. The productivities in the control and CSL experiment were 2.19 and 2.01 g/(L·h), respectively. Although the use of CSL resulted in a 10% decrease in productivity, it is viewed that its application would be economical compared to P2 medium. Hence, CSL may be used to replace the P2 medium. It was also demonstrated that inclusion of butyrate into the feed was beneficial to the butanol fermentation. A control experiment produced 4.77 g/L of total ABE, and the experiment with supplemented sodium butyrate produced 5.70 g/L of total ABE. The butanol concentration increased from 3.14 to 4.04 g/L. Inclusion of acetate in the feed medium of the immobilized cell biofilm reactor was not found to be beneficial for the ABE fermentation, as reported for the batch ABE fermentation. Names are necessary to report factually on available data. However, the USDA neither guarantees nor warrants the standard of the product, and the use of the names by USDA implies no approval of the product to the exclusion of others that may also be suitable.     

Determination of d-glucose in undiluted whole blood using chemically modified electrodes and segmented sample injection in a flow system

A flow system for the determination of d-glucose in undiluted whole blood, in which segmented sample injection and on-line dialysis are used to decrease the red cell volume fraction (haematrocrit) dependence, is described. Glucose is degraded enzymatically by means of immobilized glucose dehydrogenase. The nicotinamide coenzyme (NAD⁺) that is present in the solution is reduced in the enzymatic reaction and is reoxidized amperometically at 0 mV vs. Ag/AgCl on a graphite electrode, modified with phenoxazinium ion. The potential use of the system for clinical analysis is evaluated.     

Direct Electrochemistry of Cytochrome c on EDTA-ZrO2 Organic-inorganic Hybrid Film Modified ElectrodesState Key Laborator3.＂ of Chemo／Biosensing and Chemometrics, Hunan Universit3; Changsha. Hunan 410082. China

A composite film of ethylenediamine tetraacetic acid (EDTA)‐ZrO₂ organic‐inorganic hybrid was prepared based on the chelation between Zr(IV) and EDTA. The direct electrochemical behavior of cytochrome c (cyt. c) at the hybrid film modified glassy carbon electrodes was investigated. The immobilized EDTA can promote the redox of heme in horse heart cyt. c which gives rise to a pair of reversible redox peaks with a formal potential of 40 mV (vs. SCE). The peak current increased linearly with the increase of cyt. c concentration in the range of 1.6 × 10^?6—8.0 × 10^?5 mol·L^?1 with the correlation coefficient of 0.996. Further investigation shows that metal ions can impede the electron transfer of cyt. c. The impediment capability of metal ions depends on their coordination capability with EDTA and their valence number.     

用微芯片化学反应器实现酶催化化学发光测定葡萄糖的研究

葡萄糖是临床化学诊断以及食品分析中重要的检测项目 ,最常用的测定方法是采用葡萄糖氧化酶(GOD)催化葡萄糖与氧分子间反应 ,生成葡萄糖酸和过氧化氢 [1] ,而对过氧化氢的检测则可采用过氧化酶 (POD)催化鲁米诺的化学发光反应进行 [2 ] .FIA对整个过程的实现是十分有效的方式 ,但由于多采用固定化酶反应器 [3～ 5] 使其在制备及分析上较复杂且费用高 .由 Manz等[6] 提出的微型全分析系统(μ- TAS)在针对不同体系的微量分析及在线监测上均具有突出的优越性 .本文使用的含微混合器的微芯片化学反应器采用μ- TAS设计思想 ,建立了化学发…     

Synthesis of monodispersed organic-inorganic hybrid spheres

This paper describes the attempt to prepare a new group of monodispersed silica-polymer hybrid particles, which consists of silica and amide polymer: poly(vinylpyrrolidone) (PVP) and poly(2-ethyloxazoline) (POXZ). Preparation method is based on the growth of hybrid seeds by the addition of TEOS-polymer solution.Monodispersed PVP-silica hybrid particles of 1.24 µm in diameter were prepared by growing the hybrid seeds of 0.54 µm by the addition of TEOS-PVP solution with ammonia catalyst. In the case of POXZ-silica particles, addition of TEOS-POXZ solution to the solution containing 0.54 µm seeds resulted in monodispersed POXZ-silica hybrid particles and four times repetition of the addition for particle growth gave the hybrid particles of the diameter of 1.6 µm.Improvement of mechanical properties of hybrid particles was observed when the particles were heated at 100 200°C.     

Hydrothermal Synthesis and Structural Characterization of a Novel Organic—Inorganic Hybrid Compound {[Cu（2,2′—bpy）2]2—Mo8O26}

A novel organic-inorganic hybrid compound {[Cu(2,2′-bpy)2]2Mo8O26} has been hydrothermally synthesized and structurally characterized by single-crystal X-ray diffraction. The compound crystallizes in the orthorhombic space group, Pna21,with a=2.4164(5),b=1.8281(4),c=1.1877(2)nm,V=5.247(2)nm^3,Z=4,and final R1=0.0331,wR2=0.0727.The structure consists of discrete {[Cu(2,2′-bpy)2]2Mo8O26} clusters,constructed from a β-octamolybdate subunit[Mo8O26]^4- covalently bonded to two [Cu(2,2′-bpy)2]^2 coordination complex cations via bridging oxo groups.In addition,the spectroscopic properties and thernal behavior of this compound have been investigated by spectroscopic techniques (UV-vis,IR,Raman and EPR spectra) and TG analysis.     

Ni(phen)(H2O)(V2O6)的水热合成和晶体结构（英）

A novel compound Ni(phen)(H₂O)(V₂O₆) has been hydrothermally synthesized and structurally determined to be a two-dimensional compound, which contains {V₂O₆}_n^2n- chains interconnected by nickel(Ⅱ) complexes via oxygen atoms. The crystallographic data measured by single-crystal X-ray diffraction analysis are as follows: C₁₂H₁₀N₂NiO₇V₂, M_r=454.81, monoclinic, space group P2₁/c, a=0.784 6(3), b=2.103 6(8), c=0.942 3(4) nm, β=112.872(5)°, V=1.433 0(10) nm³, Z=4, D_c=2.104 Mg·m^-3, μ(Mo Kα)=2.615 mm^-1, F(000)=904, T=298(2) K, 4 480 reflections collected, 2 470 independent (R_int=0.032 2), the final R=0.058 4 and wR₂=0.145 7 for 2 303 observed reflections with I>2σ(I). CCDC: 192520.     

Comparative study of 8-hydroxyquinoline derivatives as chelating reagents for flow-injection preconcentration of cobalt in a knotted reactor

8-Hydroxyquinoline (HQ), 2-methyl-8-hydroxyquinoline (CH₃-HQ), 5,7-dichloro-2-methyl-8-hydroxyquinoline (Cl₂-CH₃-HQ), 5,7-dibromo-8-hydroxyquinoline (Br₂-HQ), 5-sulfo-7-iodo-8-hydroxyquinoline (ferron) and 5-sulfo-8-hydroxyquinoline (SO₃H-HQ) were compared as chelating reagents for on-line sorption preconcentration of cobalt in a knotted reactor (KR) precoated with the reagent. The results obtained with the different HQ derivatives reveal those properties of the chelating reagent responsible for the processes taking place in the KR. The influence of hydrophobicity, acidity, stability of the cobalt chelate and type of substituents in the HQ ring system on the separate steps of the flow injection (FI) preconcentration procedure are discussed. According to the performance characteristics of the different HQ derivatives, the most important parameters for on-line preconcentration in a KR are the hydrophobicity of the reagent and the stability of the chelate complex with the analyte.     

Characterization of the Converging Jet Region in a Triple Torch Plasma Reactor

Enthalpy probe measurements were taken of the converging plasma plume in a triple torch plasma reactor and related to substrate heat flux measurements. Results show excellent entrainment of process gases injected into the converging plasma plume by way of the central injection probe. At lower pressures (40 kPa), the plasma volume is equivalent to at least a 3 cm diameter, 4 cm long cylinder, with relatively uniform temperature, velocity, and substrate heat flux profiles when compared to a typical dc arc jet. Converging plasma plume size, substrate heat flux, and enthalpy profiles are also shown to be a strong function of applied system power. Substrate heat flux measurements show smaller radial gradients than enthalpy probe measurements, because of the high radial velocity component of gases above the substrate boundary layer. Enthalpy probe measurements were also conducted for diamond deposition conditions and approximate temperature and velocity profiles obtained. Problems with the uniform gas mixture assumption prohibited more accurate measurements. Reproducibility of enthalpy measurement results was shown with an average standard deviation of 11.8% for the velocity and 7.6% for the temperature measurements.