Removal of naphthalene from petrochemical wastewater streams using carbon nanoporous adsorbent

Ordered mesoporous carbon, OMC, was synthesized using ordered mesoporous silica MCM-48 as hard template, the structural order and textural properties of the synthesized materials were studied by XRD, SEM, and nitrogen adsorption-desorption analysis. Adsorption of naphthalene over various porous adsorbents such as OMC, MCM-48, and commercial activated carbon was studied from solutions with different concentration at ambient temperature (25 ± 2 °C) and pH 7. The adsorption isotherms of naphthalene were in agreement with a Langmuir model, moreover, the uptake capacity of naphthalene followed the order: OMC > commercial activated carbon > mesoporous silica (MCM-48).     

Functionalization of silicon nanowires by iron oxide and copper for degradation of phenol

Research on Chemical Intermediates - Iron oxide (Fe3O4) and copper-functionalized silicon nanowires (SiNWs) from silicon powder mesh?<?500 with a spherical structure have been...     

Chemical synthesis of zinc oxide nanorods for enhanced hydrogen gas sensing

Zinc oxide(ZnO) nanorods are prepared using equimolar solution of zinc nitrate((Zn(NO3)2) and hexamethylenetetramine(C6H12N4) by the hydrothermal technique at 80 C for 12 h. Epitaxial growth is explored by X-ray diffraction(XRD) patterns, revealing that the ZnO nanorods have a hexagonal(wurtzite) structure. Absorption spectra of ZnO are measured by UV–visible spectrometer. The surface morphology is investigated by field emission scanning electron microscopy(FESEM). The synthesized ZnO nanorods are used for detecting the 150 C hydrogen gas with a concentration over 1000 ppm. The obtained results show a reversible response. The influence of operating temperature on hydrogen gas detecting characteristic of ZnO nanorods is also investigated.     

A Series of Collaborations between Various Pharmaceutical Companies and Regulatory Authorities Concerning the Analysis of Biomolecules Using Capillary Electrophoresis: Additional Instruments/Buffer

An international project team (including members from US, Canada and UK) was formed from a number of interested biopharmaceutical companies and regulatory authorities to conduct a cross-organisation collaboration exercise. The results of the first comparison with eight different organisations that used instruments of the same equipment model, the same reagents, and the same methodology has been reported previously [1]. This report represents the addition of other instruments using a different run buffer. The relative migration times were different, as expected, prohibiting a direct comparison between companies. The within-organisation variability was low for both relative migration time (<0.34% RSD% for all companies save one) and the peak area (<5% RSD% for all companies save one) when measuring the purity of a representative IgG sample. The apparent molecular weight of bovine serum albumin was measured with good precision (less than 10% RSD% across all companies) to the theoretical value when all data is utilized (67.5 kDa compared to 66.4 kDa). For a representative IgG sample, the three main components, IgG Light Chain, IgG Non-glycosylated Heavy Chain, and IgG Heavy Chain, could not be separated, specifically the IgG Non-glycosylated Heavy Chain and IgG Heavy Chain. When the IgG Non-glycosylated Heavy Chain and IgG Heavy Chain were combined for all organisations, the fractional peak area for the IgG Light Chain and IgG Non-glycosylated Heavy Chain + IgG Heavy Chain peak also showed excellent agreement, with less than 7.5 and 3.5% RSD%, respectively. The value of this exercise is in demonstrating the reliability of CE for the determination of apparent size of biopharmaceutical proteins. This underpins the appropriate use of such CE data in support of regulatory submissions.

     

A modified fractional least mean square algorithm for chaotic and nonstationary time series prediction

A method of modifying the architecture of fractional least mean square （FLMS） algorithm is presented to work with nonlinear time series prediction. Here we incorporate an adjustable gain parameter in the weight adaptation equation of the original FLMS algorithm and absorb the gamma function in the fractional step size parameter. This approach provides an interesting achievement in the performance of the filter in terms of handling the nonlinear problems with less computational burden by avoiding the evaluation of complex gamma function. We call this new algorithm as the modified fractional least mean square （MFLMS） algorithm. The predictive performance for the nonlinear Mackey glass chaotic time series is observed and evaluated using the classical LMS, FLMS, kernel LMS, and proposed MFLMS adaptive filters. The simulation results for the time series with and without noise confirm the superiority and improvement in the prediction capability of the proposed MFLMS predictor over its counterparts.     

Dye fixation and decolourization of vinyl sulphone reactive dyes by using dicyanidiamide fixer in the presence of ferric chloride

A synthetic polymer was synthesized and used for the improvement of dyeing properties as well as decolorization of textile waste water. Two dyes were selected having anthraquinone based Remazol Blue R and azo based Remazol Red RB. It was observed that the synthetic polymer can be used as fixer for the fixation of dye by crosslinking between dye and fibre, which not only improves the dyeing properties but also helpful to coagulate the colour after dyeing. By single point method the concentrations of synthetic polymer were calculated in residual after dyeing. It was examined that the residual synthetic polymer is helpful in colour removal efficiency by coagulation of polymer with dye to form heavy molecules which settle down and decolorization occurred. Colour removal efficiency was found dependents on pH, concentration of synthetic polymer and inorganic coagulant.     

Intermolecular potential energy surface for CS2 dimer

A new four‐dimensional intermolecular potential energy surface for CS₂ dimer is obtained by ab initio calculation of the interaction energies for a range of configurations and center‐of‐mass separation distances for the first time. The calculations were performed using the supermolecular approach at the Møller–Plesset second‐order perturbation (MP2) level of theory with the augmented correlation consistent basis sets (aug‐cc‐pVxZ, x = D, T) and corrected for the basis‐set superposition error using the full counterpoise correction method. A two‐point extrapolation method was used to extrapolate the calculated energy points to the complete basis set limit. The effect of using the higher levels of theory, quadratic configuration interaction containing single, double, and perturbative triple excitations QCISD(T) and coupled cluster singles, doubles and perturbative triples excitations CCSD(T), on the shape of potential energy surface was investigated. It is shown that the MP2 level of theory apparently performs extremely poorly for describing the intermolecular potential energy surface, overestimating the total energy by a factor of nearly 1.73 in comparison with the QCISD(T) and CCSD(T) values. The value of isotropic dipole–dipole dispersion coefficient (C₆) of CS₂ fluid was obtained from the extrapolated MP2 potential energy surface. The MP2 extrapolated energy points were fitted to well‐known analytical potential functions using two different methods to represent the potential energy surface analytically. The most stable configuration of the dimer was determined at R = 6.23 au, α = 90°, β = 90°, and γ = 90°, with a well depth of 3.980 kcal mol^?1 at the MP2 level of theory. Finally, the calculated second virial coefficients were compared with experimental values to test the quality of the presented potential energy surface. © 2010 Wiley Periodicals, Inc. J Comput Chem, 2011.     

Analytical Evaluation of Cu<Superscript>2+</Superscript> Selective Behavior of calix[4]arene Derivative

The present article describes the solvatochromic effect including solvent system selection, time study and a detailed complexation study along with exploration of extraction properties of 5,11,17,23-tetrakis[(diethylamino)methyl]-25,26,27,28-tetrahydroxycalix[4]arene (4) that bears nitrogen atom as a donor group available for chelating metal ions. Complexation properties of 4 toward selected transition metal ions have been investigated by UV-visible and fluorescence spectroscopies. The% efficiency of 4 toward selected transition metal ions was found in order Cu²⁺> Ni²⁺> Hg²⁺> Zn²⁺> Co²⁺> Cd²⁺> Pb²⁺. It has been noticed that 4 is not only proved to be an efficient Cu²⁺ selective chromoionophore but also possesses an effective extraction property for transferring Cu²⁺ ions from an aqueous to dichloromethane layer. The FT-IR spectroscopic method has also been applied for further confirmation of the complexation phenomenon of 4 with Cu²⁺ ion and found adequate.