Fabrication of intra porous PVDF fibers and their applications for heavy metal removal,oil absorption and piezoelectric sensors

Intra porous fibrous membranes have enhanced metal ionic adsorption and oil separation abilities than those of intra nonporous fibrous membrane.In this paper,we prepared highly intra porous fibrous poly(vinylidene fluoride)(PVDF)membranes using an innovated water-mediated electrospinning approach.FTIR-ATR and XRD techniques confirmed the conversion of non-polarα-phase to polarβ-phase in electrospun membranes.The porous fibrous membrane M–16 had adsorbed oil almost 120%and metal adsorption around 15%,12%,5%,13%respectively for Pb^(2+),Cd^(2+),Cu^(2+)and Zn^(2+),which are larger than the counterpart of nonporous M–18.The nonporous fibrous membranes have better peak to peak output voltage(Vp-Vp)2 to 3 times than the porous fibrous membranes(M–16).The results show apparent potential applications in wastewater/oil spill treatment as well as piezoelectric sensors.

Effect and Influence of Aryl Mercaptanes with Various Chain Lengths on DNA/RNA and Cadmium Oxide (CdO) Nanoparticles Sandwiched Complex

CdO(cadmium oxide)nanoparticles show a strong peak of Plasmon absorption in ultraviolet-visible zone.A strong interaction exists between the surface of CdO nanoparticles and aryl mercaptan compounds.Aryl mercaptan compounds cause aggregation of CdO nanoparticles linked to DNA/RNA(eoxyribonucleic acid/ribonucleic acid)and hence,lead to widening of peak Plasmon of CdO nanoparticles surface at 550 nm and emerge a new peak at higher wavelength.In the current project,this optical characteristic of CdO nanoparticles is used to investigate interaction time between different aryl mercaptanes and CdO nanoparticles.The results showed that aryl mercaptan compounds with shorter chain length interact faster with CdO nanoparticles.Therefore,a simple and fast method for identification of aryl mercaptanes with various chain lengths using red shift in surficial Plasmon absorption is presented.

A nomogram for prediction of absorption rate coefficient

Background Previous studies have suggested that nomogram can simplize complicated calculations of several varibles. A simple nomogram was constructed to estimate absorption rate coefficient (k a) by using the peak time (t peak ) and the elimination rate coefficient (k e) of drugs administered orally Methods The nomogram was based on the plasma concentration-time (C-T) curve equation and the function relation between t peak , k a and k e A mathematical analysis was presented for the construction of single chart nomogram To check the degree of accuracy of the developed nomogram, we used it to analyze retrospective profiles of 46 drugs and compared the k a values obtained graphically and those calculated by numerically solving the descriptive equation In addition, we measured the carbocisteine concentration of 18 healthy volunteers by HPLC with fluorescence detection To analyze performance error, the measured carbocisteine concentrations were compared with predicted concentrations by the k a obtained from the nomograms along with the other pharmacokinetic parameters Results The estimated of k a values from nomograms were in very close proximity with the numerical values The performance error was as follows: median performance error (MDPE) and median absolute performance error (MDAPE) were 1 32% and 18 15%, respectively Conclusions The developed nomogram is accurate and reliable The size of performance error meets the demand of clinical pharmacokinetics Therefore, the nomograms can offer another convenient and easy method for rational individualized dosage regimens

Analyses and identification of the chemical constituents of the Uighur formulation Baixuan Xiatare using three-stage infrared spectroscopy

OBJECTIVE:To identify,rapidly and accurately,the chemical composition of the traditional Uighur formulation Baixuan Xiatare(BXXTR-FU).METHODS:We investigated if application of three-stage infrared(IR)spectroscopy enabled identification of the main chemical constituents(and their origins)in BXXTR-FU.RESULTS:The characteristic peaks of herbal material(s)and BXXTR-FU were assigned.In Fourier transform-IR(FT-IR)spectroscopy of BXXTR-FU,peaks at1616 and 1605 cm-1 of BXXTR-FU were considered to denote anthraquinones and their derivatives;1066 cm-1 was regarded as the characteristic absorption peak of resin glycosides.In second-derivative IR(SD-IR)spectroscopy,the main carbonyl types of BXXTR-FU in the range 1743-1636 cm-1 were assigned:1651 cm-1 belonged to the carbonyl stretching vibrations of flavonoids and chromones;1717 cm-1 belonged to tannins;1699 cm-1 belonged to carboxylic acids;1636 cm-1 belonged to anthraquinones and their derivatives.SD-IR spectroscopy further confirmed that the characteristicabsorption peaks at 1636,1618 and 1603 cm-1 could be used as markers that BXXTR-FU contained anthraquinones and their derivatives.Synchronous2 D-IR correlation spectra of chemical groups further confirmed the results of FT-IR and SD-IR spectroscopy.CONCLUSION:Our study strongly supported the necessity and importance of three-stage IR spectroscopy owing to its rapid and accurate identification of herbal formulations.

Theoretical Investigations on the Electronic and Optical Properties of Luminescent Poly（alkylthiophene-co-pyridine）

Quantum-chemical techniques were applied to investigate a series of conjugated polymers： poly（3-octylthien-2,5-ylene-co-pyrid-2,6-ylene） （pl）, poly[pyrid-2,6-ylenebis（3-octylthien-2,5-ylene）] （p2） and poly[pyrid-2,5-ylenebis（3-octylthien-2,5-ylene）] （p3） comprising alternating n-excessive 3-alkylthiophene and n-deficient meta- or para-linked pyridine moieties. Their ground state and excited state structures were optimized with density functional theory B3LYP method, and the optical properties were calculated by the time-dependent density functional theory （TD-DFT） and ZINDO/S methods. Their HOMO-LUMO gaps （An-L）, the lowest excitation energies （Eex）, ionization potentials （IP） and electron affinities （EA） were obtained by extrapolating those of the polymers to the inverse chain length equal to zero （1/n=0）. The calculated results showed that the decrease of pyridylene content increased the HOMO level and decreased the LUMO level while the para-linkage further contributed to it. The IP are in the order： p1〉p2〉p3 but EA are： p1〈p2〈p3. In addition, the decrease of the pyridylene content and the para-linked pyridylene in the backbone of the polythiophene resulted in a narrowed energy gap and bathochromic absorption and emission peaks.

Preparation,Structure,and Properties of Flexible Polyurethane Foams Filled with Fumed Silica

Flexible polyurethane （PU） foams with different load-ing mass fraction （0%-2.0%） of fumed silica were synthesized by free-rising foaming method. The addition of 1.4% fumed silica makes the cells diffuse more uniform in the PU foam and the temperature of degradation occurring with a maximum weight loss rate is about 7℃ higher than that of pure PU foam. Most signifi-cantly,the sound absorption peaks of the filled PU foams shift to the low frequency region （from 997 Hz to 711 Hz） with increasing fumed silica content （0%-2.0%）. The average sound absorption coefficients of filled PU foams increase except the content of 0.35% fumed silica. The experimental results show that flexible PU foams filled with fumed silica have excellent sound absorption characteristics in low-frequency regions.

Analysis of gamma-emitting radionuclides in soils around high energy accelerators

Objective To investigate the specific activities of gamma radionuclides in the soils around high energy accelerators,and to analyze the influence of rays emitted by nuclides with characteristic peaks at similar energy points on nuclide measurement results,in order to provide reference for the accurate identification of radionuclides.Methods GR5021 high-purity germanium gamma spectroscopy system was used to measure the specific activities of gamma-emitting radionuclides 226Ra,232Th,238U,40K and artificial radionuclides 54Mn,52Mn,7Be,22Na,59Fe,95Zr in six soil samples around three kinds of high energy accelerators,and the theoretical counts of the characteristic peak of 835.7keV were compared with the measured counts of the characteristic peak of 54Mn.Results The specific activity ranges of gamma-emitting radionuclides 226Ra,232Th,238U and 40K in the soils around three kinds of high energy accelerators were 55.5–171,34.9–99.9,21.9–79.3 and 247–680 Bq/kg,respectively.The specific activities of artificial radionuclides 52Mn,7Be,22Na,59Fe and 95Zr were basically lower than the minimum detection limit.A characteristic peak was found at the energy point of 835.7keV in six soil samples,and the corresponding total absorption peak counts were from 228Ac of 232Thdecay daughter.Conclusions The specific activities of gamma-emitting radionuclides were at the normal natural background levels.The specific activities of artificial radionuclides were basically lower than the minimum detection limits.For 232Th,when its specific activity is above 40 Bq/kg,characteristic peak of its decay daughter 228Ac could be misjudged as characteristic peak of 54Mn.