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Four cyclodextrins (CD) including &beta, cyclodextrin (&beta, CD), &gamma, cyclodextrin (&gamma, CD), heptakis-O-(2-hydroxypropyl)-&beta, cyclodextrin (HP-&beta, CD), and heptakis-O-(2, 6-di-O-methyl)-&beta, cyclodextrin (DM-&beta, CD) were used as solubilizer to study the solubility enhancement of myricetin. The results of the phase solubility study showed that the presence of CDs could enhance the solubility of myricetin by forming 1:1 complexes. Among all CDs, HP-&beta, CD had the highest solubilization effect to myricetin. The concentration of myricetin could be 1.60 &times, 10&minus, 4 moL/L when the presence of HP-&beta, CD reached 1.00 &times, 2 moL/L, which was 31.45 times higher than myricetin&rsquo, s aqueous solubility. Subsequently, the HP-&beta, CD:myricetin complex was characterized by Fourier transform infrared spectroscopy (FT-IR), X-ray diffraction (XRD), and thermogravimetric analysis (TGA). In order to get an insight of the plausible structure of the complex, molecular docking was used to study the complexation process of HP-&beta, CD and myricetin. In the complex, the A ring and C ring of myricetin were complexed into the hydrophobic cavity of HP-&beta, CD, while the ring B was located at the wide rim of HP-&beta, CD. Four hydrogen bonding interactions were found between HP-&beta, CD and -OH groups of the guest in the HP-&beta, CD: myricetin complex. The complexation energy (△E) for the host-guest interactions was calculated with a negative sign, indicating the formation of the complex was an exergonic process. A 30-ns molecular dynamics simulation was conducted to the HP-&beta, CD: myricetin complex. Calculation results showed that no large structural deformation or position change were observed during the whole simulation time span. The average root-mean-square deviation (RMSD) changes of the host and guest were 2.444 and 1.145 &Aring, respectively, indicating the complex had excellent stability.

Polyaniline (PANI) polymer coating was electrochemically synthetised by cyclic voltammetry (CV) method on stainless steel bipolar plates of proton exchange membrane fuel cell (PEMFC). Structure and morphology of PANI polymer coating were characterized by means of fourier transform infrared reflection (FTIR) spectrum and scanning electron microscopy (SEM). The corrosion behavior of the coating was evaluated by polarization curve and electrochemical impedance spectroscopy (EIS) in the medium of 1M H2SO4and 2ppM NaF at 70°C to simulate the corrosive condition of PEMFC. It was found that the optimal conditions for PANI polymer coating synthesis could be 10-15 circles when the voltage ranged from-1.2V to +1.2V(Vs.SCE) with a scan rate of 50 mV/s. SEM observation results indicated that the polymer coating presented with uniform and dense feature. FTIR results illustrated that the coating were composed of PANI. Corrosion current densities of 316L SS and PANI-coated steel were 10-5and 10-6A/cm2respectively. Corrosion potential of the coated SS shifted towards more positive values compared to the uncoated plate. EIS results indicated that the radius of the capacity impedance for PANI increased obviously.

N-heptyl-pyridine tetrafluoroborate is prepared by the double decomposition reaction of HEPB and NaBF4. The ionic liquid at room temperature used in the experiment has a significant absorption determined by UV spectrum within the range of 200-400nm, the maximum absorption wavelength of HEP-BF4ionic liquid in ethanol is 244nm. The standard working curve of HEP-BF4ionic liquid is y=0.00441+0.01563x (R=0.99912). The linear range of HEP-BF4ionic liquids in the ethanol is 1-75 mg/L. The recovery rate of HEP-BF4ionic liquid which is between 96.6% and 102%, is measured by standard addition method in ethanol.

A method for the simultaneous determination of 15 kinds of phthalate esters in edible oil by gas chromatography-mass spectrometer (GC-MS) was firstly established. The calibration curves showed good linearity in the range of 0.001~1mg /L and the correlation coefficients (r) were more than 0.999. The limits of quantification were in the range of 0.001~ 2.000 μg/L (S/N = 10). The recovery of three level ranged from 70.50% to 112.00%, at spiked levels of 0.1mg/L, 1.0mg/L and 10mg/L with the relative standard deviations (n = 6) of 0.59% ~ 7.54%. On the basis of the above method, the three edible oils under different storage temperatures were detected and the results showed that DIBP, DBP and DEHP were detected in two samples. This method possesses high sensitivity and low detection limit and can be used for quantitative analysis PAEs in edible oils.

A GC/MS method was established for the determination of phthalates plasticizers in bottled beverages. The calibration curves are all linear in the range of 0.01 to 5μg/L with correlation coefficients greater than 0.997. The recoveries are in the range between 97.27% and 105.05% under two levels. The testing data of the samples showed that the five bottled beverages all contained DBP, DIBP and DEHP plasticizers, and DIBP content was obviously higher than the other two.

A conversion coating was obtained in the molybdate based bath on hot dip galvanized steel. The influence of the bath service life and bath component variation on the corrosion resistance of the conversion coating were investigated. Corrosion resistance of the coating was evaluated by electrochemical technique in 3.5%NaCl. It is found that the anodic branch of polarization curves presented in passivation character. Electrochemical impedance spectroscopy (EIS) results confirm that the radius of the capacity impedance for molybdate film decreased with treating area, which reveals that the bath life and bath component variation affected anti-corrosion performance of the coating remarkablely. The bath constituent was analysed by inductively coupled plasma atomic emission spectrometry (ICP), and the results show that the bath will lose the passivation ability after treating 1.16m2sample area for new prepared treating solution of 500ml. The surface morphologies of the coatings were observed using scanning electron microscopy (SEM), and the element composition of the coatings was detected using energy dispersive X-ray (EDX). The investigation results indicate that uniform and compact film is formed on the surface of the galvanized steel, and the film is composed of zinc,oxygen, phosphor and molybdenum.

Calcium carbonate (CaCO3) whiskers were firstly treated by sodium stearate, and then blended with polypropylene (PP) to prepare the composites by a closely intermeshing co-rotating twin-screw extruder at 200°C. The performance of the composites, such as thermal behavior, microstructure and mechanical properties, were analyzed with differential scanning calorimetry (DSC), thermogravimetric analysis (TGA), X-ray diffraction (XRD), scanning electron microscopy (SEM) and mechanical testing. The results showed that CaCO3 whisker influenced the crystalline behavior of PP phase in the blends because of its intervening. Moreover, thermo-decomposing temperature, tensile and bending strengths of the blends all increased with increasing whisker content. CaCO3 whiskers had good reinforcing and toughening effects on PP.