Biorefinery based on biomass resources is an important approach for the oil refining and petrochemical industry to achieve sustainable development. Two types of biorefinery suitable for China s biomass resources are presented in

The studies over forty years on rare earth catalysts in polymer syntheses of diene, alkyne, alkylene oxide, thiirane, carbon dioxide copolymerization, lactide, caprolactone, cyclic carbonate and so forth in China have been reviewed.

The structure, morphology and hydrogen- storage capacity of MS₂ (M = Mo, Ti) nanotubes prepared by different experimental methods were studied. It was found that the MoS₂ nanotubes treated by KOH displayed the gaseous storage capacity of 1.2 wt% hydrogen (under the hydrogen pressure of 3 MPa and 25!) and the electrochemical discharge capacity of 262 mAh/g (at the discharge current density of 50 mA/g and 25!) that corresponds to about 1.0 wt % hydrogen. In comparison, TiS₂ nanotubes can store 2.5 wt% hydrogen under the hydrogen pressure of 4 MPa and 25!. The results show that MS2 compound nanotubes are promising materials for hydrogen storage.

The polycrystalline materials of SrWO₄ were synthesized by means of a solid phase reaction with analytical purity SrCO₃ and WO₃ at high temperature. The transparent SrWO₄ single crystal with dimension of φ 22 mm×40 mm has been successfully grown along a-axis by Czochralski method. X-ray powder diffraction results show that the as-grown SrWO₄ single crystal belongs to tetragonal system and I4₁/a space group. The measured density of SrWO₄ is 6.439 g•cm^-3 by buoyancy method. The effective segregation coefficients of W and Sr elements in SrWO₄ single crystal are close to 1 by the X-ray fluorescence method.

A W/O microemulsion was prepared with Span80-PS (petroleum sulfonate) as complex emulsifier, isopropanol as cosurfactant and kerosene as oil phase. The optimal constituents of microemulsion were found from pseudoternary phase diagrams: the mass ratio of Span80 to PS was 4:1 and complex surfactant to cosurfactant was 1:1. The Fe₃O₄ magnetic fluid was obtained by one-step method with the W/O microemulsion as microreactor to synthesize magnetic nanoparticles (reaction temperature was 30! and reaction time was 5 h) and kerosene as carrier liquid. The magnetic fluid was investigated by TEM, XRD and fluorescence microscope. The magnetism was determined by Gouy magnetic balance. The average particle size of Fe₃O₄ was 7.4 nm, and magnetic particles were well-dispersed. The stable Fe₃O₄ magnetic fluid with good magnetism may be produced by one-step method in the W/O microemulsion. Accordingly, the traditional preparation method of magnetic fluid can be simplified greatly.

Stereoselective 1,3-dipolar cycloadditions of exo-glycals 1 to nitrones 2, 5 and 8 were investigated under the catalysis of Lewis acid or in a refluxing benzene or toluene solution, and afforded the corresponding cycloadducts of ketosyl spiro-isoxazolidines. The reductive cleavage of the N-O bond in the isoxazolidine ring and debenzylation by the catalytic hydrogenation [Pd(OH)₂/C] were approached using the glucose-type cycloadducts 6b and 6e to alkyl-C-glycoside derivatives 12, providing a new access to a novel alkyl-C-glycoside containing an amino group on the side alkyl chain.

A total of eleven new 1-(1-methoxy-1-ferrocenyl-3-arylpropan-2-yl)-1H-1,2,4-triazole derivatives have been synthesized from acetylferrocene. The structures of the title compounds have been determined by elemental analysis, ¹H-NMR and single crystal X-ray diffraction analysis. Bioassay showed that some of the title compounds had high plant-growth regulatory activity.

Three 3,4-dihydroxy-2,5-bis-(2'-(4'- substituted-oxazolinyl)) furans were synthesized at 90%-94% yields from reaction of 3,4-dihydroxyfuran-2,5-dicar-boxylic acid or its dimethyl ester with chiral ?-amino alcohol via a one-step process. Their chemical structures were determined by ¹H NMR, IR, MS, and elemental analysis. With these chiral bisoxazoline ligands, the asymmetric reductive reaction of ?-acetonaphthalene with KBH₄ or NaBH4 was preliminarily studied. The enantiomeric excess of the reduction product was up to 83.2% with cyclohexane as the solvent, the molar ratio of ligand: reductive agent: β- acetonaphthalene is 0.04:1.6:1, and 72-hours reaction time at 0!. Furan-containing bisoxazoline with 4-benzyl on oxazoline rings exhibited higher enatioselectivity than congeneric bisoxazolines with 4-ethyl on oxazoline rings.

An ionic liquid (IL) was prepared by directly mixing InCl3 and 1-methyl-3-butylimidazolium chloride (BMIC) with molar ratio 1:1 under dry argon atmosphere. The densities, and surface tension of pure IL were determined at temperature range of (278.15 to 343.15±0.1K). The properties for ionic liquid based on group III were discussed using Glasser s theory. The standard entropy, the surface energy and the crystal energy of ionic liquid were calculated, respectively. The crystal energy of ionic liquid is much lower than ionic solid and this is the underlying reason for forming ionic liquid at room temperature. In addition, a new theoretical model of IL, that is interstice model, was applied to calculate the thermal expansion coefficient of BMIInCl₄. The order of magnitude for the thermal expansion coefficient, α, calculated by the theoretical model is in good agreement with experimental value. The result shows that there is much reasonableness for the interstice model of ionic liquid.

The bioreaction mechanism and kinetic behavior of protein enzymatic hydrolysis for preparing active peptides were investigated to model and characterize the enzymatic hydrolysis curves. Taking into account single-substrate hydrolysis, enzyme inactivation and substrate or product inhibition, the reaction mechanism could be deduced from a series of experimental results carried out in a stirred tank reactor at different substrate concentrations, enzyme concentrations and temperatures based on M-M equation. An exponential equation dh/dt = aexp(-bh) was also established, where parameters a and b have different expressions according to different reaction mechanisms, and different values for different reaction systems. For BSA-trypsin model system, the regressive results agree with the experimental data, i.e. the average relative error was only 4.73%, and the reaction constants were determined as Km = 0.0748 g/L, K_s = 7.961 g/L, kd = 9.358/min, <>emk2 = 38.439/min, E_a = 64.826 kJ/mol, Ed = 80.031 kJ/mol in accordance with the proposed kinetic mode. The whole set of exponential kinetic equations can be used to model the bioreaction process of protein enzymatic hydrolysis, to calculate the thermodynamic and kinetic constants, and to optimize the operating parameters for bioreactor design.

A new water soluble compound trisodium 5,3 2, 5 2-trisulfonate-2,3,4,4 2-tetrahydroxy-deoxybenzoin (TTDB) was synthesized and characterized by IR, UV, ¹H NMR, and elemental analysis. The single crystal of TTDB was determined by X-ray single crystal diffraction. The scavenging effect of compounds on hydroxy radicals was detected by fluorescent spectrophotometry. The electrochemical behavior of compounds in nonaqueous solution DMF was carried out by means of cyclic voltammetry. The experimental result shows that the crystal [C₁₄H₁₇Na₃O₁₈S₃] belongs to monoclinic, space group C2/c with unit cell constants a = 1.4223(4) nm, b = 2.4327(8) nm, c = 1.3596(4) nm, α = 90o, β = 113.044(5)o, γ = 90o, Z = 8, V = 4.329(2) nm3, D<>subc = 1.925 mg/m³, F(000) = 2568, F_w = 638.43, R₁ = 0.0950, wR₂ = 0.2648. The half effective concentration EC₅₀ of scavenging hydroxy radicals of compound THDB is 53.1 μmol/L, while that of scavenging hydroxy radicals of compound TTDB is 47.3μmol/L. The electrochemistry redox processes of THDB and TTDB are different from each other.

Divergently synthesized carbosilane dendrimers generations 1 (G1) and 2 (G2) with allyl end groups were bonded onto silica gel. Reactions between the dendrimers and acid-processed silica gel took place, with toluene reflux and organic base as catalyst. Chemically bonded silica gel was characterized by transmission electron microscopy (TEM), infrared (IR)?and other methods. The chemically modified silica gels were packed into high-pressure liquid chromatography (HPLC) column and their separation characters were evaluated. G2-bonded silica gel was effective in separating homologous compounds of alcohol, alkyl-substituted benzene, N-substituted benzene, metacrylic acid ester and phthalate.

N,N-Dimethylformamide (DMF)/H₂O mixtures were used as solvents to fabricate azo polyelectrolyte (PEAPH)/poly(diallyldimethyl ammonium chloride)(PDAC) self-assembled multilayers with the layer-by-layer electrostatic adsorption technique. PEAPH is a copolymer of acrylic acid and azobenzene-containing acrylate. The effect of the ratio of DMF to water on the multilayer growth, structure and surface morphology was studied in some details. Results show that DMF/H₂O mixtures are proper media for PEAPH/PDAC multilayer fabrication. The ratio of DMF to water in the mixture has significant influence on the multilayer structure and surface morphology. With the increase of DMF content, the multilayer thickness has a better linear growth relationship with the bilayer number, and the multilayer surface becomes smoother. Moreover, azo chromophores show less H-aggregation when the multilayers are fabricated from DMF/H₂O mixtures with higher DMF contents. These studies demonstrate that using organic solvent and water mixtures is an effective way to control the multilayer construction by adjusting the media properties. This method can be applied to multilayer fabrication of other water-insoluble polyelectrolytes.

Polysulfone nanofibers were prepared by electrospinning. The electrospinning equipment was designed in a new way, wherein the spinneret was combined with a gas jet device. The intrinsic viscosity of the used polysulfone was 0.197 dL/g in dimethyl acetamide, which was also the solvent in electrospinning. The gas used in this gas jet/electrostatic spinning was nitrogen. The relationship between the process parameters and the average diameter of polysulfone nanofibers was investigated. The main process parameters studied in this work were the voltage, the flow rate of the spinning fluid, the distance between the spinneret and the nanofiber collector and the temperature in the spinning chamber. The other important factors determining the nanometer diameter were the spinning fluid properties including its viscosity, surface tension and electrical conductivity. The average diameter and the diameter distribution of electrospinning nanofibers were measured experimentally by using scanning electron microscopy. The diameter of polysulfone nanofibers prepared by the gas jet/ electrostatic spinning was in the range 50-500 nm. It was found that the diameter of nanofibers mainly depended on high voltage, the gap between the spinneret and the collector and the concentration of polymer solutions. It is concluded that the gas-jet/electrospinning is a better method than the conventional electrospinning, in that it makes the nanofibers finer and more uniform and exhibits higher efficiency in the process of electrospinning.

Water-borne raspberry-like PMMA/SiO₂ nanocom-posite particles were prepared via free radical copolymerization of methyl methacrylate (MMA) with 1- vinylimidazole (1-VID) in the presence of ultrafine aqueous silica sols. The acid-base interaction between hydroxyl groups (acidic) of silica surfaces and amino groups (basic) of 1-VID was strong enough for promoting the formation of long-standing stable PMMA/SiO₂ nanocomposite particles when 10 mol% or more 1-VID as auxiliary monomer was used. The average particle sizes and the silica contents of the nanocomposite particles were in the ranges from 120-330 nm and 15%-20%, respectively. TEM and SEM observations indicated a raspberry-like morphology of the obtained nanocomposite particles.

Ionic liquid like 1-butyl-3-methyl- imidazolium tetrafluorobrate ([BMIM]BF4) has been used as solvent and electrolyte for the electropolymerization of aniline at glassy carbon electrode by cyclic voltammetry. Electrode modified with polyaniline (PAn) has obvious electrochemical activity in ionic liquid and acid solution (pH 0-4), and has significant electrocatalytic activity for redox reaction of catechol and hydroquione.

Polystyrene-graft-polydimethylsiloxane (PS-g-PDMS) copolymers with different PDMS content were synthesized by the radical bulk copolymerization of PDMS macromonomer and styrene. The copolymers were characterized by Fourier transform infrared (FT-IR),¹H-nuclear magnetic resonance (NMR), thermogravimetric analysis (TGA), dynamic mechanical analysis (DMA), transmission electron microscopy (TEM) and the mechanical properties of the copolymers were also carried out. It was indicated that the notched impact strength and elongation at break of the polymers increased with the increase of PDMS content. The thermal stability of PS-g-PDMS is better than that of PS.