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The microwave digestion-ICP-AES was used to detect the Cr, Cd, Pb, As, Hg and Ni in cordycepsmilitaris from Shenyang. The method accuracy was proved by the national standard method. The result shows the sequence of heavy metals was Pb>Ni >As > Cd> Cr, and Hg was not detected, as was detected in few sample. All the data showed that cordycepsmilitaris accords with the national standards. The method average recovery is 94.07%-107.58%, and RSD is 0.84%-3.25%. It is a promising analysis method on detection of heavy metals in cordycepsmilitaris.

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.

PANI coating was electrochemically synthesized by cyclic voltammetry (CV) method on the surface of 316L stainless steel plate. The surface morphology of PANI coating was observed by scanning electron microscopy. The effect of oxygen gas on corrosion behavior of PANI coating in PEMFC environment was investigated. The corrosion performance of the coating was evaluated by potential-time curve and polarization curve as well as electrochemical impedance spectroscopy in a bath containing 1M H2SO4and 2ppM NaF, and the air with a flow rate of 10 ml/min was piped into the testing corrosion cell to simulate the positive cathode condition of PEMFC at 70°C. The potential-time curves illustrated that oxygen gas resulted in the potential decline towards negative direction. Polarization curves showed that corrosion potential of the sample with O2was lower than that of the sample without O2, and the corrosion current density was higher than that of the sample without O2. EIS results indicated that the Nyquist plots were constitute of a capacitive impedance arc and a incline line, and the oxygen gas reduced the anti-corrosion performance of the PANI coating.

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.

Adopting microwave digestion and ICP-AES method while detecting Ni, Cr, Pb, Cd, As and Hg in edible fungus of Liaoning province, results show that the acceptance rate of heavy metal in lentinus edodes, oyster mushrooms, pleurotus eryngium, agrocybe cylindracea, agaricus bisporus, black fungus, coprinus comatus, cordyceps militaris was above 90%, Hg was not checked out, only in exceptional sampals Pb, Cd, Cr have checked out but not exceed, Ni and As out of limits, but the superscale was very small, the lentinus edodes in Liaoning province in a great measrue was safty.

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 non-chromate conversion coating was prepared from molybdate based bath on the surface of Zn-5%Al hot dip galvanized steel. The influence of the preparation conditions such as temperature, bath pH and treating time on the corrosion resistance of the obtained conversion coating was investigated. The corrosion performance of the film was researched using electrochemical technique in 3.5%NaCl. The results indicate that the anodic branch of the polarization curves present in passivation character. Electrochemical impedance spectroscopy (EIS) illustrate that the radius of the capacity impedance for conversion coating varies distinctly according to the preparation condition. The surface morphology was observed using scanning electron microscopy (SEM), and the results show that the surface of Zn-5%Al hot dip galvanized steel present in eutectic feature after conversion coating treatment. The chemical composition of the coating was detected by energy dispersive X-ray (EDX), and the results illustrate that the conversion coating is composed of Zn, Al , O, P and Mo.

Coating of ME20M magnesium alloys was first carried out using electroless nickel plating technique with an environmentally-friendly pretreatment. The morphology and specific weight loss of the pickling process were investigated. The Ni-P coating was characterized by its structure, morphology, chemical composition, adhesion strength and corrosion resistance. The SEM image shows that the pyrophosphate pickling process can produce a rough surface and the thermal shock test indicates excellent adhesion strength between magnesium alloys and Ni-P coating. The damp heat test and electrochemical measurement prove the Ni-P coating significantly increase the corrosion resistance of ME20M magnesium alloys.

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.

In roughage, ten trace elements as Pb, Se, Mn, Se, Zn，Sb, Hg, Sn, Ca, Mg were detected by ICP-AES. Method of high pressure nitrifying pot is also selected to nitrify roughage. The relative standard deviation of measurement was less than 2.60%. The results accord with the demands of analysis trace elements. The experiment proved that roughage contained rich useful trace elements, which was green food with high nutrition.

This paper studies the influence of current frequency on the micro-arc oxidation (MAO) process, microstructrue and the properties of the formed alumina coatings. The amount of discharge sparks increases and the spark moves more quickly with increasing the frequency of current pulse. SEM results show that the size of the discharge products decreases. The anodic cell voltage decreases with increasing the frequency of power supply, however, the cathodic cell voltage increases. The thickness and roughness of the coating produced using frequency of power supply 50 Hz are high. Increasing the frequency, the thickness of the coating decreases, but coating surface becomes even, and the coating possesses better corrosion protective property

Cytisine (Cy) is one of the alkaloids that exist naturally in the plant genera Laburnum of the family Fabaceae. With strong bioactivities, Cy is commercialized for smoking cessation for years. In this work, the study of intermolecular interactions between Cy and bovine serum albumin (BSA) was performed by applying fluorescence spectroscopic methods under simulated physiological conditions. The mechanism of fluorescence quenching of BSA by Cy was also studied. Parameters such as bathing temperature, time and solution pH were investigated to optimize the fluorescence quenching. The binding type, binding ratio and binding constant between BSA and Cy were calculated by using the Stem-Volmer equation. Experimental results indicated that Cy can quench the fluorescent emission of BSA statically by forming a 1 : 1 type non-covalent complex and the binding constant is 5.6 x 10(3) L x mol(-1). Synchronous fluorescence spectral research shows Cy may affect the fluorescence emission of Trp residues of BSA. Furthermore, molecular docking is utilized to model the complex and probe the plausible quenching mechanism. It can be noted that the hydrogen bindings and hydrophobic interactions between Cy and BSA change the micro-environment of Trp213, which leads to the fluorescence quenching of BSA.

In order to study the reducing and reusing of petrochemical residual sludge and solve the technical problem of traditional anaerobic digestion, the contrast research was carried out between the mesophilic (30°C) and thermophilic (60°C) anaerobic digestion. The result showed that the efficiency of thermophilic digestion was twice as big as that of mesophilic digestion. When sludge dosage increased, the concentration of volatile fatty acid rose sharply and pH value decreased correspondingly. When the reaction became stable, the concentration of volatile fatty acid began to drop and the corresponding pH value began to rise gradually. At each sludge dosage, alkalinity dropped first and then increased with the reaction carried on. In a different sludge dosage, the fluctuation of pH, volatile fatty acid, and alkalinity under the thermophilic condition was less than that under the mesophilic condition by a different sludge dosage. Through the experiment of sludge digestions, the optimizing technical con...

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.

The thermal conductivity at (220 to 480) K of anodic alumina film of (1.4 to 5) μm thick and about 30 % porosity, which is grown from aluminum foil, is reported. A laser flash technique was employe...

Abalone and sea cucumbers are useful, which is related with trace elements in them. In the present paper, using high-pressure sealed nitrifying pots for digestion of samples, Orthogonal test was applied to the determination of 15 kinds of trace elements in abalone and sea cucumber such as Fe, Ca, Mg, Zn, Sr, Se, Hg, Cd etc by ICP-AES. The orthogonal table of L16 (4(4)) and experiment programs were designed. More information could be obtained with a small number of experimental times by combining chemistry with mathematical statistics, and the best experimental operation conditions could be chosen by square-error analysis. The method was simple, rapid, highly sensitive and accurate, but also features multi-element determination at the same time, with little environment pollution. The recovery rate of the method is in the range of 91.0%-110.0%, and relative standard deviations is less than 3.55%. The experimental results showed that both abalone and sea cucumber are of nutritional value of seafood, and are rich in Fe, Ca, Mg, Zn, Sr and other kinds of trace elements helpful to the human body. At the same time, because of severe environment pollution, seawater pollution should not be neglected. When seawater was polluted, hazardous substances were deposited in abalone or sea cucumber body with high levels of harmful heavy metals. Therefore, it should be a reminder that people must be careful to eat them.

In the present paper, samples were digested by high pressure digestion pots, reducing the loss of trace elements during the digestion process. The contents of trace elements in edible fungi such as Ca, Na, K, Mg, Mn, Ba, Fe, Co, Ge and Cu were determined by inductively coupled plasma atomic emission spectrometry. The relative standard deviation with high pressure digestion pots was 0.160-2.860, and that with wet method was 0.33%-3.49%, so it could be seen that the measurement precisions of the two methods were good, and the former was better. The measurement results with the two methods were checked by t-test, and the values in the range of 0.002 4-2.473 were lower than t(0.99, 9) (3.25). The measurement results showed that the two methods had no obvious differences, namely no system errors occurred. The recovery rates with high pressure digestion pots were in the range of 96.6% -103%. The method of high pressure digestion pots was suitable for the determination of trace elements in edible fungi with the advantages of being simple, rapid, sensitive, stable and accurate etc., and the results were satisfactory.

The contents of eight trace elements Zn, Co, Fe, Mn, Mg, Ca, Cu and K in scallop were determined by ICP-AES and AAS using nitrifying method of high pressure nitrifying pot. The comparison between the results of two analysis methods was made, which proved no obviously differenct. The recoveries were 93.3%-102.8%, and the relative standard deviations were less than 1.60%. The experiment proved that scallop contains rich and useful trace elements, not only tastesgood and fresh, but also is essential supplemental elements that human body can not synthesize by itself.

In the present paper, Chemometrics was applied to the determination of 20 kinds of trace elements in human hair by ICP-AES. The method was simple, rapid, highly sensitive and accurate. The determination of many elements could be performed at the same time. The recoveries of the method were in the range of 94.07%-107.6%, and the relative standard deviations were less than 3.49%. According to the results of 1 600 human hair samples with various ages from different regions, the influences of nutrition and environmental pollution upon human health were studied. Thereby, the comparison of and research on the living environment were carried out.

This paper studied the seed germination rate, chlorophyll content, net photosynthetic rate, SOD activity, and Cu and Pb absorption of Agrostis stolonifera and Festuca arundinacea under Cu and Pb pollution. The results showed that Cu and Pb pollution had a significant effect on the seed germination rate of F. arundinacea. The chlorophyll content of F. arundinacea decreased dramatically under Pb and Cu-Pb pollution, while decreased slightly under Cu pollution. No significant effect of Cu and Pb was observed on the chlorophyll content of A. stolonifera. The SOD activity of A. stolonifera increased under 350 mg Cu x kg(-1) and all test concentrations of Pb, while that of F. arundinacea only increased under 700 mg Pb x kg(-1) and 350 mg Cu x kg(-1) + 1100 mg Pb x kg(-1). The net photosynthetic rate of F. arundinacea decreased more under Pb pollution than under Cu pollution, but that of A. stolonifera all decreased under Cu or Pb pollution. It was suggested that A. stolonifera was more tolerant in physiological characteristics to Cu and Pb pollution than F. arundinacea, while F. arundinacea was more tolerant to Cu than to Pb. The Cu absorption amount of F. arundinacea was relatively large, but did not increase with increasing Cu pollution. A. stolonifera had a high absorption ability of Pb, and the absorbed Pb amount was increased with increasing Pb pollution. A. stolonifera and F. arundinace could be the potential phytoremediation plants for Pb and Cu-polluted soil, respectively.

In this paper,the contents of trace elements in beans such as Ca, Mg, Mn, Sr, Fe, Co, Ni, Se and Ba were determined by ICP-AES uing nitrifying method of high pressure nitrifying pot, and compared with the results of wet method. The two methods showed no obvious differences. The method proves to be simple, rapid, highly sensitive, accurate and can be used to determine many elements at the same time. In addition, there was little environment pollution. Its recovery is 96.8%-102%, and relative standard deviation is 3.35%.

In this paper, orthogonal test was applied to determination of trace elements in wild vegetables just as Mn, Se, Cu, Fe, Mg and Zn by ICP-AES. It could provide many informations for us by less experimental times, and could choice the best experimental conditions by square-error analysis. It would be helpful for improving experimental accuracy. The method was simple, rapid, and possessed of highly sensitivity, good accuracy and determination of many elements at the same time, in addition little environment pollution. The recoveries of the method were in the range of 97.2%-103.3%, and relative standard deviations were less than 2.15%. The experimental results proved wild vegetables were valuable and nutritious food, they had rich trace elements.