Advanced Materials Research Vols. 726-731

Abstract: In_xBi_1-xVO₄ photocatalyst particles were prepared by low temperature solid reaction using nitrate of indium and bismuth and NH₄VO₄ as the starting materials, and followed by the sintering at various temperatures. The as-prepared samples were investigated by X-ray powder diffraction (XRD), and the photocatalytic activity was carried out by the concentration change of methylene blue in the solution after visible light irradiation. The experiment results show that the orthorhombic phase InVO₄ is dominant in the photocatalyst samples prepared at sintering temperature higher than 600°C. In addition, the increase in indium content in the In_xBi_1-xVO₄ particle has greatly improved the photocatalytic activity for decomposition of aqueous methylene blue under visible light irradiation.

Abstract: Iodometric determination of dissolved oxygen is used as experimental methods, through the determination of oxygen consumption of crude oil, gasoline , diesel , three different types of oil, oxygen consumption of Philippines clams and oxygen consumption of Philippines clams under the conditions of three oil pollution, variations of DO under the conditions of three oil pollution is researched. The results show that oxygen consumption of gasoline> oxygen consumption of diesel oil> oxygen consumption of crude oil. At the same time, oxygen consumption of gasoline changes with time by a big margin, diesel oil comes second, oxygen consumption of crude oil changed slightly with time.

Abstract: irreversible transferring precipitation in ethanol solution is applied to form the target using the flavone extracted from herbal sarcandra by means of ultrasonic extraction at m (Ge 4): m (herbal sarcandra flavone) = 3:10,PH=4.5-5.5, constant temperature 40-45 °C and 20-min stir as khaki-colored complex, which is to be precipitated, separated, purified, and examined through FTIR,UV,XRDand ascertained as herbal-sarcandra-flavone germanium.

Abstract: Deoxynivalenol (DON) mimotope, designated as CDON, is an epitope (CMRPWLQ) immunoscreened from a phage-displayed random peptide library. In order to replace the conjugated toxin with non-toxic recombinant proteins in ELISA, two novel expression vectors, which were designated as plasmid pGEX-CDON and phagemid pC89S4-CDON for producing GST-CDON and pVIII-CDON fusion proteins in E.coli were constructed. After purification, both GST-CDON and pVIII-CDON fusion proteins show good reactogenicity with an anti-DON antibody in a competitive inhibition ELISA test. When GST-CDON was used as coating antigen, the linear range of the competitive inhibition ELISA is from 62ng/ml to 410ng/ml, the linear equation is Y= 186.6-23.87Ln (X), IC₅₀ is 194ng/ml. For pVIII-CDON as coating protein, the linear range of the competitive inhibition ELISA is from 20ng/ml to 470ng/ml, the linear equation is Y = 161.3-25.49Ln (X), R2=0.9962, IC₅₀ is 94ng/ml. ELISA analysis and comparison show the reactogenicity and specificity of pVIII-CDON binding to anti-DON antibody are better than GST-CDON fusion protein. The pVIII-CDON is promising in establishing an ELISA without the use of the toxic mycotoxin conjugate.

Abstract: The composite absorbent polymer was synthesized by the solution polymerization method with acrylic acid, starch and bentonite as raw materials, N, N-methylene-bis-acrylamide as cross-linking agent, and ammonium persulphate as initiator. The whole process was under nitrogen protection. Factors including amount of starch, crosslinker, initiator, monomer, and neutralization degree and reaction temperature were investigated in terms of their influences on water absorbency. Effect of bentonite amount on polymer strength and water absorption rate was also tested. The modified polymer, with the composition of 10% corn starch, 0.15% initiator, 0.05% crosslinking agent and 8% bentonite, showed a significant strength enhancement at 65°C and 80% neutralization degree (molar ratio) with water absorption of 1012g/g in deionized water and 92g/g in 0.9% NaCl solution.

Abstract: The paper presents a novel method for the flotation separation of Cu²⁺ using microcrystalline adsorption system loaded with CuI prior to the determination by spectrophotometry. The effects of different parameters,such as the dosages of KI, ascorbic acid and octadecyl trimethyl ammonium bromide (OTMAB),various salts and acidity etc. on the flotation yield of Cu²⁺ have been investigated. The possible flotation separation mechanism of Cu²⁺ was discussed.The results showed that under the optimum conditions,octadecyl trimethyl ammonium bromide cation (OTMAB⁺) reacted with I^- to produce the microcrystalline matter (Ms-M) of (OTMAB⁺·I^-), Cu²⁺ could be reduced to Cu⁺ by ascorbic acid,and then Cu⁺ reacted with I^- to form the precipitation of CuI.The precipitation of CuI was quantificationally adsorbed on the surface of Ms-M of (OTMAB⁺·I^-) and was floated above water phase, the liquid-solid phases were formed with clear interface. In this condition, K⁺,Na⁺,Ca²⁺,Mg²⁺, Zn²⁺,Co²⁺,Al³⁺,Mn²⁺,Ni²⁺ and Fe²⁺ could not be floated.Therefore, Cu²⁺ was separated completely from the above metal ions.A new spectrophotometric method of determination of trace copper by flotation separation using microcrystalline adsorption system loaded with CuI was established.The proposed method has been successfully applied to the determination of Cu²⁺ in various environmental water samples, and the results agreed well with those obtained by AAS method.

Abstract: This study investigates the copigmentation effect and its underlying mechanism of tannin on Mahonia bealei anthocyanins (MBA). Results show that the addition of tannin increases the absorption and maximum absorption wavelength of MBA. At pH 3.73, the activation energy of MBA-tannin adduct is 2.43 times that of MBA. Under the same temperature, MBA-tannin complex shows better heat stability as exemplified by lower degradation rate and longer half-time. The light-induced degradation rate constant of MBA-tannin is 93.33% of that of MBA. It is shown in this paper that tannin can improve the heat and light stability of MBA and therefore is efficient as a copigment. Finally, the IR spectra suggest that the copigmentation effect is due to the formation of hydrogen bonds between tannin and MBA via associated hydroxyl groups.

Abstract: As a burgeoning technology based on conventional clarifier technology, pellet fluidized bed (PFB) technology has been widely applied in kinds of high SS water treatment process. In this paper, PFB process was used to thicken the alum sludge in a water plant in south China with scale of 1.0~2.5m³/h. The experimental results showed that, increasing flocculent (PAM) dosage could decrease outlet turbidity, and average up pellets settling behavior. Under the experimental condition, there exist negatively linear relationship between process maximum flow rate which ranged from 1.6m³/h to 2.2 m³/h and raw sludge concentration. Moreover, because of the improvement of pH environment and flocs chemical structure, additional lime dosage would enhance maximum surface loading and save PAM dosage. The pilot scale experiment proved that by applying PFB, alum sludge conditioning could achieve satisfied results characterised by high surface loading, low outlet turbidity, and high concentration thicken sludge with fine dewaterability.

Abstract: Catalytic hydrolysis decomposition of dichlorodifluoromethane (CCl₂F₂) in the presence of water vapor and oxygen was studied over solid acid MoO₃/ZrO₂ using a fixed-bed reactor. The CCl₂F₂ adsorption was multilayer chemical adsorption and its process was corresponding with Freundlich model. Its heat was from 56.3 to 73.2 KJ.mol^-1, and it was exothermic reaction and chemical adsorption.

Abstract: A hydrothermal catalytic oxidation degradation process was investigated to improve acetic acid production from cellulose simulants. Filter paper, being a cellulose simulant as the test material, was oxidized in a batch reactor with catalysts. An L¹⁶ (45) orthogonal array design (OAD) with five factors at four levels was employed. Of the five, reaction temperature was the most influential for the yield of acetic acid. Afterwards, a series of process optimization experiments were conducted. And a higher yield of acetic acid (28.53%) was obtained under the following conditions: temperature was 320°C; reaction time was 26 min; water consumption was 8 ml; oxidant and catalyst supplied were 0.8% and 0.2% of the raw material respectively.