Research of Inclusion Complexation of 4,4'-Thiodiphenol Effected by β-Cyclodextrin in Aqueous Solutions and the Effect on Photodegradation

The inclusion behavior of 4,4′ -Thiodiphenol (TDP),a typical bisphenol and endocrine disruptor,reacts with β-cyclodextrin (β-CD) in aqueous solutions has been investigated by means of UV absorption spectrum and quantum-chemical calculation with Gaussian 98 software. The results show that the inclusion behavior of TDP is quite different in acidic solutions (pH 5.9) from that in alkaline solutions (pH 10.0). This behavior difference is attributed to the different formula structures in aqueous solutions at acidic and alkaline pH values that are demonstrated by quantumchemical modeling and calculation. TDP forms a 1∶1 β-CD inclusion complex in aqueous solutions. The equilibrium constant K was calculated to be 553.49 L/mol at pH 5.9 and 1 318.20 L/mol at pH 10.0 respectively for the inclusion complex reaction by using the modified Benesi-Heldbrand equation. After inclusion TDP's structure is changed especially at the inclusion part with the bond order becoming larger,which results in inhibitive photodegradation during direct photooxidation and H2O2 assisted photooxidation.     

Research of Inclusion Complexation of 4,4＇-Thiodiphenol Effected by β-Cyclodextrin in Aqueous Solutions and the Effect on Photodegradation

The inclusion behavior of 4, 4＇ -Thiodiphenol （TDP）, a typical bisphenol and endocrine disruptor, reacts with β-cyclodextrin （β-CD） in aqueous solutions has been investigated by means of UV absorption spectrum and quantum-chemical calculation with Gaussian 98 software. The results show that the inclusion behavior of TDP is quite different in acidic solutions （pH 5.9） from that in alkaline solutions （pH 10.0）. This behavior difference is attributed to the different formula structures in aqueous solutions at acidic and alkaline pH values that are demonstrated by quantum- chemical modeling and calculation. TDP forms a 1 ： 1 fl-CD inclusion complex in aqueous solutions. The equiiibrium constant K was calculated to be 553.49 L/mol at pH 5.9 and 1 318.20 L/mol at pH 10.0 respectively for the inclusion complex reaction by using the modified Benesi-Heldbrand equation. After inclusion TDP＇s structure is changed especially at the inclusion part with the bond order becoming larger, which results in inhibitive photodegradation during direct photooxidation and H2O2 assisted photooxidation.     

Preparation,Characterization and Antioxidant Activity of Inclusion Complex of Bakuchiol with Hydroxypropyl-β-cyclodextrin

Bakuchiol isolated from Psoralea corylifolia is a naturally occurring prenylated phenolic monoterpene with a variety of bioactivities. The aim of this study was to improve the water solubility and thermal stability of bakuchiol through complexing it with hydroxypropyl-β-cyclodextrin(HP-β-CD). The bakuchiol/HP-β-CD inclusion complex's behavior and characterization were investigated by ultraviolet-visible(UV-vis) spectroscopy, Fourier transform infrared spectroscopy(FT-IR), thermogravimetric analysis(TGA),X-ray diffraction(XRD),~1H nuclear magnetic resonance(NMR), and two-dimensional(2 D) NMR. The obtained results indicated the formation of 1∶1 inclusion complex for bakuchiol with HP-β-CD. Water solubility of bakuchiol was significantly improved by complexation with HP-β-CD as demonstrated by phase solubility studies. The encapsulation of bakuchiol was confirmed by UV-vis, FT-IR, and XRD. The thermal stability was effectively enhanced by TGA and derivative thermogravimetry(DTG) analysis. In vitro antioxidant activity showed that bakuchiol/HP-β-CD inclusion complex had a little higher antioxidant ability than free bakuchiol. Moreover, we got the possible inclusion mode for the bakuchiol/HP-β-CD inclusion complex through NMR analysis. These results suggest that the inclusion complex can be a potentially useful approach in the design of novel formulations of bakuchiol for medical applications.     

Photoelectrochemical synergetic degradation of Acid Orange II with TiO2 modified β-PbO2 electrode

Electrochemically assisted photocatalysis is an effective approach to improve photocatalytic efficiency. In this paper, modified β-PbO2 electrode was prepared by TiO2 co-deposition and characterized by SEM and XRD. Then 2.0g TiO2 modified β-PbO2 electrode (2.0 g TiO2 involved in the 200 mL co-deposition solution) was used in electrochemically assisted photocatalytic degradation of Acid Orange II and the influence of initial pH values was investigated when the potential applied across the electrodes was 1.5 V. When the potential applied was 2.5 V, the difference of the degradation process and the final products were studied. The results indicated that 2.0 g TiO2 modified β-PbO2 electrode was different from the unmodified one in that the β-PbO2 crystals became finer and the electrode became more compact and more uniform. The synergetic effect in electrochemically assisted photocatalytic degradation of Acid Orange Ⅱ was observed and degradation efficiency and TOC removal were the highest at initial solution pH 2.0. By UV-visible spectral analysis, it was proved that photoelectrochemical synergetic degradation of Acid Orange Ⅱ went through the step of producing main product maleic acid for the solution at the initial pH 2.0 within 2 h, but the degradation was slow for the solution at the initial pH 12.0.     

Synthesis of Novel Chitosan Microspheres Grafted with β-Cyclodextrins and Their Adsorption for Iodine for Antibacterial Activities

The novel chitosan microspheres grafted with β cyclodextrins (CMGC) were prepared by means of the reaction of chitosan microspheres and mono-(6-p-tosyl)- β-cyclodextrins (β-CD-OTs-6). β-CD-OTs-6 were gained by the reaction of p toluenesulfonyl chloride (TsCl) and β-cyclodextrins (β-CDs). Their structures were proved by Fourier transform infrared spectral analysis (FT-IR), X ray powder diffraction analysis, and ^13C NMR; the configuration of CMGC was characterized by scanning electron micrograph (SEM) and transmittance electron micrograph (TEM). The inclusion complex of CMGC with iodine was prepared and its inclusion ability was studied. The experimental results showed that some iodine was included with CMGC and formed a stable inelusion. The stable complex of CMGC and iodine (CMGC-I) shows good antibacterial effect.     

~1H NMR Investigation of Supramolecular Complex between β-Cyclodextrin and Cholesterol

A supramolecular complex between β-cyclodextrin and cholesterol was synthesized and characterized via proton 1H NMR spectroscopy. In the supramolecular complex,the stoichiometric proportion of β-cyclodextrin to cholesterol is 1:2. The possible conformation of the supramolecular complex was depicted according to the chemical shift variance of proton 1H NMR of the host and guest molecules inside the inclusion complex. Removal efficiency of cholesterol complexed by β-cyclodextrin in our work is increased to a remarkable extent. This result can be applied in the field of drug development to reduce cholesterol in blood and other human organs.     

Synthesis and Property Studies of Transparent Resins Containing Rare Earth Complex Eu(Ⅲ) (TTA)_2(MA)_2 Phen·H_2O

A new rare earth complex Eu(Ⅲ)(TTA)2(MA)2Phen·H2O was synthesized and characterized by element analysis, FTIR, UV, thermal analysis, and fluorescence spectra. The strong fluorescence and high thermal stability of Eu(Ⅲ)(TTA)2(MA)2Phen·H2O were used to modify resin. The copolymer containing europium was prepared by copolymerization of Eu(Ⅲ) and styrene/α-methylacrylic acid, and characterized by FTIR and fluorescence spectra. The fluorescence spectra showed that the copolymer was a sort of materials with good ...     

Catalysis of organic pollutant photodegradation by metal phthalocyanines immobilized on TiO<Subscript>2</Subscript>@SiO<Subscript>2</Subscript>

A TiO2@SiO2 hybrid support was prepared by the sol-precipitation method using n-octylamine as a template.The photocatalyst manganese phthalocyanine tetrasulfonic acid (MnPcS) was immobilized on the support to form MnPcS-TiO2@SiO2.X-ray diffraction (XRD) and UV-Visible diffuse reflectance spectra (UV-Vis DRS) were employed to characterize the catalyst.The photocatalytic degradation of rhodamine B (RhB) and the catalytic oxidation of o-phenylenediamine (OPDA) under visible light irradiation were used as probe reactions.The mineralization efficiency and the degradation mechanism were evaluated using chemical oxygen demand (COD Cr) assays and electron spin resonance (ESR),respectively.RhB was efficiently degraded by immobilized MnPcS-TiO2@SiO2 under visible light irradiation.Complete decolorization of RhB occurred after 240 min of irradiation and 64.02% COD Cr removal occurred after 24 h of irradiation.ESR results indicated that the oxidation process was dominated by the hydroxyl radical (·OH) and superoxide radical (O-·2) generated in the system.     

Recognition of linear dicarboxylate anions by the host with two naphthylurea groups

The compound 1 with preorganized structure was synthesized, and its absorption and fluorescence spectra in the presence of dicarboxylate anion were studied. The results showed that the emission of compound 1 at 380 nm could be quenched via addition of dicarboxylate anion, and a structureless red-shift emission band at 500 nm appeared simultaneously. These phenomena could be caused by the formation of the complex of compound 1 and dicarboxylate anion.According to the results of fluorescence spectra and 1H-NMR, the binding constant of pimelate with compound 1 has the largest value, owing to the most suitable conformation of compound 1 for pimelate.     

Pressure Dependence of Molar Volume near the Melting Point in Benzene

The pressure dependence of the molar volume was at constant temperatures close to the melting point in benzene. The molar volume of benzene was calculated using experimental data for the thermal expansivity for constant temperatures of 25℃, 28.5℃, 40℃, and 51℃ at various pressures for both the solid and liquid phases. The predictions are in good agreement with the observed volumes in both the solid and liquid phases of benzene. The predicted values of the molar volume for a constant temperature of 28.5℃ in the liquid phase of benzene agree well with experimental data in the literature.     

Sonochemical Decolorization of Methyl Orange in Aqueous Solution

The sonochemical decolorization of Methylene Orange was studied using a 24 kHz Ultrasound device with a 1.4 cm diameter horn. pH, power density, the effects of pH and power density on decolorization were discussed. The combined effect of radiate time, the initial concentration of dyes and the addition of Fe^2＋ on the decolorization was studied using response surface methodology. The results showed that the factorial central composite design was successfully employed for experimental design and predication of the results. AtpH = 2.8, T=30℃, power denstity= 300 W/L and Fe^2＋ of 2 mg/L, the decolorization percentage of 5 mg/L dye solution reached 96% after 60 mill ultreatment. The rate of decolorization of the dye was greatly improved in the presence of Fe^2＋. The sonolysis of the dye followed first-order kinetics.     

Photocatalytic degradation of metronidazole in aqueous solution by niobate K<Subscript>6</Subscript>Nb<Subscript>10.8</Subscript>O<Subscript>30</Subscript>

The photocatalytic degradation of antibiotic metroni-dazole in aqueous solution by niobate K6Nb10.8O30 photocatalyst that was prepared using a soft-chemical method was studied by Fourier transform infrared spectroscopy and UV-Vis absorption spectrum. Metronidazole is very stable and is difficult to degrade under UV irradiation. K6Nb10.8O30 photocatalyst cannot degrade metronidazole without UV irradiation and shows very high photo-catalytic activity for the degradation of metronidazole under UV irradiation. The photocatalytic degradation rate of metronidazole increased with increasing the dosage of K6Nb10.8O30 photocatalyst. The photocatalytic degradation reaction of metronidazole by nio-bate K6Nb10.8O30 follows the first-order kinetic equation.     

Anisotropic Raman spectroscopy of a single β-Ga2O3 nanobelt

The polarization dependence of the Raman spectra of a single ultra-wide β-Ga2O3 nanobelt was studied.The spectra were found to strongly depend on the relative angle between the polarization of the incident light and the axis of the β-Ga2O3 nanobelt.Such behavior was ascribed to the large length to width ratio of the nanostructure and its small dielectric constant.The ultra-wide β-Ga2O3 nanobelt was fabricated using catalyst-free thermal chemical vapor deposition.     

Studies on the interactions of 2,5-diphenyl 1,3,4-oxadiazole and 2,5-diphenyl 1,3-oxazole with β-cyclodextrin

Interactions of 2,5-diphenyl 1,3,4-oxadiazole (PPD) and 2,5-diphenyl 1,3-oxazole (PPO) with β-cyclodextrin (β-CD) are studied by 1H-NMR and steady-state fluorescence measurements, and the stoichiometries and the association constants are estimated. It is found that the hydrophobic interaction is the main driving force for the formation of inclusion complexes of PPD and PPO with β-CD. In the presence of aliphatic alcohols (from 1-propanol to 1-pentanol), PPD and PPO transfer from the CD cavity to the aqueous phase. Quenching experiments of PPD and PPO by iodide further prove the above conclusions. The results suggest that stereo effect is the crucial factor to the inexistence of nanotube in PPD (or PPO)-β-CD systems.     

SEM in-situ investigation on fatigue cracking behavior of P/M Rene95 alloy with surface inclusions

The low-cycle fatigue behavior of powder metallurgy Rene95 alloy containing surface inclusions was investigated by in-situ observation with scanning electron microscopy (SEM). The process of fatigue crack initiation and early stage of propagation behavior indicates that fatigue crack mainly occurs at the interface between the inclusion and the matrix. The effect of inclusion on the fatigue crack initiation and the early stage of crack growth was very obvious. The fatigue crack growth path in the matrix is similar to the shape of inclusion made on the basis of fatigue fracture image analysis. The empiric relation between the surface and inside crack growth length, near a surface inclusion, can be expressed. Therefore, the fatigue crack growth rate or life of P/M Rene95 alloy including the inclusions can be evaluated on the basis of the measurable surface crack length parameter. In addition, the effect of two inclusions on the fatigue crack initiation behavior was investigated by the in-situ observation with SEM.     

Mechanism of oxidative damage to DNA by Fe-loaded MCM-41 irradiated with visible light

The mechanism of oxidative damage to deoxyribonucleic acid (DNA) by iron-containing mesoporous molecular sieves (MCM-41) irradiated with visible light was elucidated. Fe-loaded MCM-41 (Fe/MCM-41) was used as a photocatalyst and the damage to calf thymus DNA caused by hydrogen peroxide (H2O2) was studied. The damage and extent of oxidation of DNA were measured by high-performance liquid chromatography (HPLC) and intermediate products were detected by HPLC/electrospray ionization tandem mass spectrometry. Electron spin resonance was used to detect changes in reactive oxygen species and peroxidase catalytic spectrophotometry was used to determine the concentration of H2O2. The results indicated that Fe/MCM-41 efficiently activated H2O2 in solution at pH 4.0-8.0 under irradiation with visible light. The photocatalytic system degraded DNA most effectively at pH 5.0-6.0 but also operated at pH 8.0. At pH 4.2, the degree of DNA damage reached 25.65% after 5 h and the kinetic constant was 5.89×10 2 min 1. Damage to DNA was predominantly caused by hydroxyl radicals generated in the system. The mechanism of DNA damage is of potential concern to human health because it can occur in neutral solutions irradiated by visible light.     

Photocatalytic oxidation of ammonia by Bi2WO6 nanoplates using fluorescent light

Photocatalytic oxidation under fluorescent light with BizW06 was used to oxidize ammonia. The results showed that the NHa＋/NH3 could be totally converted into NO3- and trace amount of NO2- in an alkaline solution. It was revealed that the photocatalytic oxidation efficiency was affected by the pH values and the initial concentration of the pollutant. Possible mechanism of photocatalytic oxidation in the system is proposed. The superoxide spe- cies （O2-） captured by the superoxide dismutase levels could accelerate the photocatalytic oxidation reaction. The indoor fluorescent lamp as the light source will be a promising option for future applications of photocatalytic technology.     

Synthesis and Spectrum Characteristic of the Inclusion Complex of β-CD and Pyridine-CuI

The β-Cyclodextrin consists of seven D-glucopyranoside units, which are linked by α-1, 4-glycosidic linkages. The shape of CD can be presented as a truncated cone. Its inner is hydrophobic and exterior is hydrophilic for the aggregation of the hydroxyl groups, which results in cyclodextrin to have the ability of inclusion different compounds.     

Synthesis and Spectrum Characteristic of the Inclusion Complex of β-CD and Pyridine-CuI

1Introduction The β-Cyclodextrin consists of seven D-glucopyranoside units, which are linked by a-1, 4-glycosidic linkages. The shape of CD can be presented as a truncated cone. Its inner is hydrophobic and exterior is hydrophilic for the aggregation of the hydroxyl groups, which results in cyclodextrin to have the ability of inclusion different compounds.     

Co-oxidation of arsenic(Ⅲ) and iron(Ⅱ) ions by pressurized oxygen in acidic solutions

The co-oxidation of As(Ⅲ) and Fe(Ⅱ) in acidic solutions by pressured oxygen was studied under an oxygen pressure between 0.5 and2.0 MPa at a temperature of 150℃. It was confirmed that without Fe(Ⅱ) ions, As(Ⅲ) ions in the solutions are virtually non-oxidizable by pressured oxygen even at a temperature as high as 200℃ and an oxygen pressure up to 2.0 MPa. Fe(Ⅱ) ions in the solutions did have a catalysis effect on the oxidation of As(Ⅲ), possibly attributable to the production of such strong oxidants as hydroxyl free radicals(OH·) and Fe(IV) in the oxidation process of Fe(Ⅱ). The effects of such factors as the initial molar ratio of Fe(Ⅱ)/As(Ⅲ), initial pH value of the solution, oxygen pressure, and the addition of radical scavengers on the oxidation efficiencies of As(Ⅲ) and Fe(Ⅱ) were studied. It was found that the oxidation of As(Ⅲ) was limited in the co-oxidation process due to the accumulation of the As(Ⅲ) oxidation product, As(V), in the solutions.