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An efficient method of preparing nanostarch using high-intensity ultrasonic irradiation and acid hydrolysis was discussed. The transmission electron microscope (TEM) showed that the nanosized starch particles were in shape of sphere with the size of 80-120 nm, and their surfaces were rough with many flocci. The Fourier transform infrared spectrometer (FT-IR) revealed that the products maintained the original biological characteristics, and the molecules did not undergo any chemical changes. In addition, the effects of experimental conditions were analyzed and a plausible mechanism was proposed to explain the formation of the nanostarch.

Polystyrene/Fe3O4composite microspheres were prepared by miniemulsion polymerization. The composite microspheres comprised of polystyrene core and magnetite nanoparticles as shell. Magnetite is modified with silane coupling to modify strong hydrophilic property, for a function of co-stabilizer. Acrylic acid as a co-monomer was employed to link polymer with magnetite nanoparticles. The microspheres were homogeneous distribution, The thickness of the shell was from10nm to 25nm. The morphology and structure of the composite microspheres were characterized by FT-IR, TEM, XRD, TG and XPS et al. The Effects of co-monomer, auxiliary emulsifier, emulsifier on the composite microspheres have been discussed.

A phosphate rock containing MgO 7.95% and SiO29.64% has fine dissemination size, which is from Yichang city in Hubei province, China. Technical conditions of the ore were investigated by performing the desilication process of double reverse flotation, which adopted GE-609 to flotate silicon. The results showed that under defoamer DE-1 36g/t, phosphate concentrate with P2O531.91%, MgO 0.97%, SiO29.46% and recovery of 88.71% were obtained by employing the process of close-circuit reverse flotation.

Lanthanum-copper Composite Oxide Compounds were prepared from lanthanum chloride (LaCl3) and copper chloride (CuCl2), and used sodium hydroxide (NaOH) as precipitating agent. The research results showed that: the best preparation condition, which is the copper content3%;water bath temperature,70°C; agitation time,2 hours; calcination temperature,400°C; calcination time,1hour.The adsorption capacity of adsorbent was 63.88mg/g in this state. Analysis results indicate that Copper-doped crystal form dense granule in favour of phosphate adsorption .And La2O3is very important on removing the phosphate.

Concentrations of 6 kinds of phthalic acid esters (PAEs) in sewage sludge from 20 typical municipal wastewater treatment plants (WWTPs) in Jiangsu province were determined by gas chromatography-mass spectrometry (GC-MS) . The results shows that the sewage sludge samples contain phthalic acid ester compounds, which total content of phthalic acid esters ( PAEs) range from 15.126 to 71.107 ug/g (dry sludge). The content of diethylhexyl phthalate (DEHP) is the highest, which amounts more than 80% of total phthalic acid esters (PAE); the content of dimethyl phthalate (DMP) is low ,which is less than 1.0 ug/g;Diethyl phthalate (DEP), dibutyl phthalate (DBP) and benzyl butyl phthalate (BBP) are detected in each sludge sample, but which content display greater difference; Dioctyl phthalate (DOP) in most cities is not detected.

In order to take full advantage of straw liquefied product to make the best mechanical properties of polyurethane synthesis. This experiment studied on the Synthesis technology of polyurethane elastomer by straw liquefied product. Under the role of catalyst,by using butanol as a liquid agent, at 160 °C, 2h later ,we could obtain straw liquefied products, Synthesis of polyurethane elastomer with two-step method, through orthogonal test and the performance testing of the finished product . The results showed that: curing agent is 3% (1:33), the initial reaction temperature is 40 °C, curing time is 8h, the mechanical properties were the best. Key words: Straw, Liquefied product, polyurethane elastomer

The solubility of benzothiazolium methylsulfate ([HBt [CH3SO3]) in binary solvent mixtures of ethyl benzoate and alcohol was measured by equilibrium method. It was found that the solubility of [HBt [CH3SO3] in this mixture increased with alcohol in mixture scaling up at the same temperature. When the composition of mixture was the same, the increase rate of solubility of [HBt [CH3SO3] in binary solvents was very different at various temperature range. All the solubility data were correlated with three thermodynamics models, and the average relative deviation (ARD) of the calculated value of the three models and the measured values was all less than 2.94%. The thermodynamics models revealed that the degree of association of [HBt [CH3SO3] decreased with the alcohol ratio reducing in binary solvents, the fusion enthalpy of HBt [CH3SO3] remained the same at the range from 233.1K to 293.1K. At last, it was summarized that the change rule of content of related components of [HBt [CH3SO3] + ester + alcohol ternary system at different conditions, and some properties of the system were forecasted. The research in this text was hoped to provide meaningful reference for the use and recycling of ionic liquid.

The diameters of 22 ionic liquids and radius of their cations and anions were calculated by DFT method. The calculation method of distance between cation and anion was set up according their diameters and radius. The relationship between glass transition temperature of ionic liquids and above parameters was investigated using multiple linear regression method and the correlation coefficient was 0.96. The model provided theory methods to calculate glass transition temperature of different ionic liquids.

Corrosion control of glutaraldehyde biocide for 304 stainless steel in simulated cooling water system containing sulfate-reducing bacteria (SRB) was studied by electrochemical impedance spectroscopy (EIS) and potentiodynamic polarization. The results revealed that impedance values of stainless steel electrode increased gradually while the passive current densities decreased with the increasing concentration of glutaraldehyde. The biocide improved good anti-corrosion performance to stainless steel in bacteria system. The impedance value |Z|0.05 increased from 19.72 kΩ·cm2 to 33.77 kΩ·cm2, and the passive current density reduced from 0.93 μA·cm-2 to 0.16 μA·cm-2 when the glutaraldehyde concentration reached 80 mg/L.

During fish processing, a large amount of waste, of the original raw materials is generated, such as skin, bone, scale, viscera and head. These useful resources have been mainly used as feedstuff or fertiliser with low value. To make more effective use of underutilized resources, collagen was isolated from the skin of Amiurus nebulosus using acetic acid and characterized for their potential usage in commercial applications. The yield of acid-soluble collagen (ASC) was 62.05% while the maximum absorbance of ASC was at 234 nm. Amino acid composition and SDS - PAGE suggested that the collagen is possibly possessive of type I collagen. Moreover, FTIR investigations showed the existence of helical arrangements of collagen where the denaturation temperature (Td) and shrinkage temperature (Ts) were 29.8°C and 65.12°C, respectively. There is a possibility that ASC could be utilized as an alternative source of collagen for food, cosmetic, biomedical and pharmaceutical purposes.

Using Amiurus nebulosus skins collagen as a kind of emulsifier in the mayonnaise, instead of a part of yolk. Based on the viscosity and organoleptic evaluation to determine the optimal formula: 0.2% Amiurus nebulosus skins collagen, 72% oil, 12.5% yolk, 9% water, 2.0% salt, 2.0% sugar, 1.1% monosodium glutamate and 1.5% spice. The experimental result showed that Amiurus nebulosus skins collagen had the advantage of emulsifying and mouthful in mayonnaise application.

Lycopene is gaining more and more attention because of its physiological activities, and it is widely used in food additives, cosmetics and other industries. For lycopene production by microorganism, lycopene-producing strains were screened from oil-immersed soil. A strain of S-1 was successfully screened by analysing the cells extract using thin-layer chromatography (TLC). On the basis of morphological characteristics and sequence analysis of 26S rDNA of strain S-1, the strain S-1 was identified as Rhodotorula mucilaginosa. The lycopene production by Rhodotorula mucilaginosa in fermentation broth reached 7.4 mg/L by 108 h.

In our study, a new kind of water treatment composite was prepared by melt blending and molding foaming, with synthetic rubber EPDM as the matrix, graphite oxide modified glass fiber (GF) as the filler. The foamed composite had a certain adsorption capacity of methylene blue dye in the water and toluene. With the increase of the graphite oxide modified GF, the composite on the methylene blue adsorption rate was increased, however, for toluene, the rate of adsorption was reduced. Due to restrictions on the oxidation of graphite and composite structures and the adsorption capacity of the material was limited.

Electrochemical behaviors of Ce3+/Ce4+ couple in mixed acid (H2SO4 and CH3SO3H) were investigated on Pt electrode. Polarization curves and electrochemical impedance spectroscopy (EIS) were used to optimize mixed acid composition, and the mixed acid consisting of 1.0 M methanesulfonic acid (MSA) and 0.8 M sulfuric acid is singled out as the optimum electrolyte. Subsequently, the effects of current density and electrolyte temperature on the electrochemical oxidation of Ce3+ to Ce4+ were researched. A 92.2% current efficiency was achieved at 40 mA•cm-2 in cerium (III) solution with the optimum mixed acid electrolyte above at 313 K. It can satisfy the application of mediated electrochemical oxidation process with Ce3+/Ce4+ mediator.

Formation damage is mainly due to the reduction of reservoir energy and the increase of flow resistance from reservoir. According to this theory, low carbon acid compound deplugging technology is introduced to improve well productivity. The compound blocking remover which will be used is consist of low carbon acid, rudimentary fatty acid and surfactant and so on. Where geological condition a large volume of carbon dioxide gas generate, through increasing the reservoir energy, removing all kinds of reservoir choke, the well productivity will increase effectively.

Objective To optimize the preparation technology of salicylic acid liposome gel. Method Salicylic acid liposome was prepared with reverse evaporating method, and liposome gel was prepared using carbomer-940 as matrix. The encapsulation efficiency and leaking percentage of salicylic acid liposome was determined with centrifugal method, and the preparation technology of liposome gel was optimized with orthogonal test. Results The encapsulation efficiency of salicylic acid liposome was 75.86％, leaking percentage was 1.37％. The optimal preparation technology of liposome gel were carbomer 3g, glycerol 15g, mixing temperature 40°C, mixing time 15min. Conclusion Reverse evaporating method was a good method to prepare salicylic acid liposome with higher encapsulation efficiency and better stability. The optimized preparation process of liposome gel was desirable, and the characteristics of product was stable and uniform.

Through inclusion of different polymer chains with different properties into polyurethane matrix, such as poly(ethylene glycol) (PEG), poly(ε-caprolactone) (PCL), poly(lactic acid) (PLA), or poly(tetramethylene oxide) (PTMG), degradable polyurethane foams (PUFs) with different molecular structure were prepared. Influences of molecular structure on PUF materials’ performance were studied systematically. When PEG, PCL, PLA, and PTMG serve as soft segment, PUFs’ storage modulus and glass transition temperature (Tg) of PUFs decrease with following order: PLA>PCL>PEG>PTMG (flexibility of PUFs varies oppositely). And degradability decreases according to following order: PEG>PLA>PCL>PTMG. With increasing content of PEG or PLA chains in PU matrix, mechanical performance of PUFs decrease gradually, but remains on the same order with conventional non-degradable PUFs. Through control on the contents of different kinds of polymer chains in soft segments of PUFs, fairly good degradability can be achieved, at whilst their basic mechanical performance is well guaranteed.

Thermal decomposition characteristics of two kinds of calcium based organic compounds-calcium propionate and the product of the modified calcium hydroxide by propionic acid-under O2/N2 atmosphere and O2/CO2 atmosphere are investigated through thermogravimetric analysis. Thermal events of CP and MCP are divided into three segments. The second and the third ones for the two compounds are similar. O2/CO2 atmosphere reduces mass loss rate peak of the second segment and postpone the third segment. O2 concentration of 10 % is inadequate for a fast and sufficient reaction. When O2 concentration is enriched to 20 %, the whole process is shifted towards lower temperature zone. Further heightening O2 concentration to 30 % or 40 %, the effect is not remarkable.

Pot-mode cultivation experiments were carried out to study the impacts of nitrogen（urea）fertilization in different level on Cadmium (Cd) accumulation, nitrate contents and nutritive values in Chinese cabbage, The results showed that: at different level of Cd artificial enriched soil, with applied urea increased, the accumulation of Cd in edible part of Chinese cabbage gradually decreased. Nitrate Contents in edible part have a positive correlation with the concentration of Cd in soil and the nitrogen fertilizer applied. In the natural soil (with contaminated Cd in concentration of 0.18 mg/kg), when the urea was fertilized by 255 kg/hm2 to 330 kg/hm2, Cd and nitrate contents of edible parts of cabbage were within the national food security limits, which could guarantee the food security of Chinese cabbage. Increasing nitrogen fertilization in the form of urea has a certain effect on amino acids contents but little effect on soluble sugar contents in Chinese cabbage, when the concentration of urea was 320 kg/hm2, amino acids contents of cabbage reached the highest level of 355 mg/kg1. Increasing nitrogen fertilization could lower down the contents of water-soluble Cd and the available Cd in soil, thereby reduce the absorption of Cd by Chinese cabbage. To a certain extent, increasing nitrogen fertilization could increase the food security of Chinese cabbage.

Two new coordination polymers, [Zn(PyHBIm)2(IPA)]•3H2O (1), [Cd(PyHBIm)(IPA)(H2O)2]•2H2O (2), were synthesized under hydrothermal conditions based on 2-(3-pyridyl)benzimidazole (3-PyHBIm) and isophthalic acid (IPA). The complexes were characterized by single crystal X-ray diffraction. They contain simple 1D chains and can be assembled into a 3D network through aromatic π–π stacking interactions and hydrogen bonding interactions. Their luminescent properties were studied in the solid state at room temperature.

The influence of melting process on heavy metal speciation was studied. The results show that although there are different changes of heavy metals Cd, Cu, Mn and Zn after melting process, percentage of residue is increasing and others are decreasing. Before melting process, Pb exists mainly in carbonate, Fe-Mn oxide and organic matter bound fractions and in Fe-Mn oxide bound fraction after the process. The percentage distribution of Cr, As, Ba and Ni are not changed obviously before and after melting. In general, the existence forms of all testing heavy metals trend to more stable speciation after melting process.

In order to study effects of lysozyme and nisin on fresh-keeping refrigerated fillets, fresh Ctenopharyngodon idellus were slaughtered and washed, then the Ctenopharyngodon idellus were divided into three treatment groups, and dipped in 0.025%, 0.05%, 0.075%, 0.1%, 0.125% lysozyme solution (group A) for 5min, 0.005%, 0.01%, 0.015%, 0.02%, 0.025% nisin solution (group B) for 5min, and Samples in the control treatment had no enzyme added to the water (group C, untreated) for 5min, then kept in 4°C after vacuum packaging. Sensory assessment, pH, total volatile basic nitrogen (TVB-N) and total plate count were determinated to evaluate the fish quality. The result indicated that lysozyme and nisin solution could delay the spoilage of refrigerated fillets fish.

Pepsin-soluble collagen (PSC) was successfully extracted from the skin of Amiurus nebulosus. The skin of Amiurus nebulosus was immersed in 0.3 mol/L acetic acid (1: 20, m: V) for 6 h at 37°C, while pepsin was added, at a level of 5000U/g dosage of defatted skin. The maximal yield of the collagen was 97.44%, which was higher than that of acid-soluble collagen (ASC) at 62.05%. Some properties of pepsin-soluble collagens from the skin of Amiurus nebulosus were characterized. Amino acid composition and SDS-PAGE suggested that the collagen might be classified as type I collagen. Moreover, FTIR investigations showed the existence of helical arrangements in PSC of Amiurus nebulosus skin of collagen. There is a possibility to use Amiurus nebulosus skin collagen as an alternative source of collagen for industrial purposes and subsequently it may maximize the economical value of the fish.

Polyurethane (PU) with mixed poly(ethylene glycol) / poly(ε-caprolactone) (PEG/PCL) soft segments is a representatively kind of degradable polyurethane material. Polyurethane foams (PUF) with mixed PEG/PCL soft segments were synthesized by using one pot method, and their mechanical and dynamic mechanical properties were investigated. Influences of PEG/PCL weight ratio and molecular weight of soft segments on PUF's mechanical and dynamic mechanical properties were studied. The results showed that: with increasing content of PCL, PUF's tensile strength, elongation at break, stress at certain tensile/compressive strain and storage modulus increased gradually; with increasing molecular weight of soft segment, PUF's elongation at break increased, but tensile strength, stress at certain tensile/compressive strain and storage modulus all decreased accordingly; glass transition temperature (Tg) of PUF with various soft segments decreased according to the following sequence: PEG-400, PCL-210N, PEG-1000 and PTMG1000; loss factor of PUF with PEG/PCL mixed soft segments was higher than that of PUF with individual PEG or PCL soft segments.

The semiconducting behavior of passive film formed on 316L stainless steel in borate buffer solution containing sulfide was studied by capacitance measurements. The results indicate p-type semiconducting behavior related to chromium oxide of the passive film at -1.12 ~ -0.78V and n-type semiconducting behavior to iron oxide at -0.47 ~ +0.35V, with an acceptor density 11.21020 cm-3 and a donor density 7.501020 cm-3 respectively. The existence of sulfide in the solution obviously increases the acceptor densities which reaches to 215.61020 cm-3 with the sulfide concentration of 12 mgL1, and therefore have a more conductive behavior.

Ni-based WC composite coatings conducted on the surface of 45 steels by free spraying followed with high frequency induction remelting were investigated. The influences of induction remelting time on properties of the coating were discussed. The wear resistance of the coating and the elemental diffusion cross the interface between the coatings and the substrate were analyzed. The compositions and microstructure of the coating before and after a wear test were characterized by scanning electron microscope with energy dispersive X-ray microanalysis. The results indicate that a coating which is free from crackers and pores composed of Ni-based solid solution and dispersed tungsten carbide is obtained by free spraying and induction remelting. The interface is a white lamellar zone. The mutual diffusion of iron and nickel in the interface proves it’s an atomic bonding between the substrate and the coating. The wear mechanisms of the coated sample are abrasive wear and microplowing. The wear resistance of Ni-based WC composite coatings is superior to that of quenched high carbon steels.