Polyaniline/akaganéite nanocomposite for detoxification of noxious Cr(VI) from aquatic environment

In this work, a removal of toxic hexavalent chromium Cr(VI) ion from aqueous solution was investigated and studied using nanocomposite of polyaniline (PANI) and akaganéite nanoparticles (NP). HCl doped PANI, and akaganéite NPs were prepared by chemical oxidative polymerization and co-precipitation techniques, respectively. The synthesized materials were characterized by Fourier transform infrared spectroscopy (FTIR), X-ray diffraction (XRD), scanning electron microscope (SEM), and high-resolution transmission electron microscope (HRTEM). It was indicated that the formed oxide NPs were consisted of akaganéite as dominant phase plus minor phases of hematite, magnetite, and/or maghemite. HRTEM images of the prepared nanocomposite demonstrated that the phases of oxide NPs embedded in the nanocomposite had the same crystallinity and morphology of pristine oxide NPs. It was found that size of nanocomposite particles has diameter ranged from 8.95 to 16.21 nm. Cr(VI) removals in a wide pH range from 2 to 9 were appropriated for prepared nanocomposite. The nanocomposite has demonstrated high removal percentage of 99.2 % and removal capacity of 17.36 mg/g for 7.0 mg/L Cr(VI) polluted aqueous solution at pH 2.0 for 5-min contact time. The synthesized nanocomposite was applied to remove Cr(VI) from a leather tanning wastewater sample with efficiency of 93.4 %.     

Evaluation of the Effect of Different Nano-Size of WO3 on the Structural and Mechanical Properties of HDPE

Journal of Inorganic and Organometallic Polymers and Materials - The new category of high-density polyethylene HDPE/WO3 was synthesized via compression molding technique. Various amounts (10, 15,...     

Determination of the order of surface reactions in Li2O

An analysis of the different surface reactions taking place in Li₂O was performed in order to determine whether adsorption and desorption of tritium are first or second order reactions. Data from BEATRIX-II Phase I and CRITIC-I were used as basis for calculations.It was found that only second order adsorption/desorption on the surface of Li₂O can predict the tritium behavior observed experimentally.     

Selective nano alumina supported vanadium oxide catalysts for oxidative dehydrogenation of ethylbenzene to styrene using CO2 as soft oxidant

Nano alumina-supported V₂O₅ catalysts with different loadings have been tested for the dehydrogenation of ethylbenzene with CO₂ as an oxidant. High surface area nano-alumina was prepared and used as support for V₂O₅ as the catalyst. The catalysts were synthesized by impregnation techniques followed by calcinations and microwave treatment, denoted as V₂O₅/γ-Al₂O₃-C and V₂O₅/γ-Al₂O₃-MW, respectively. The V₂O₅ loading was varied on nano-alumina from 5 to 30 wt%. The support and catalysts were characterized by X-ray diffraction (XRD), Barett–Joyner–Halenda (BJH) pore-size distribution, N₂-adsorption isotherms, Fourier transform infrared (FT-IR), scanning electron microscopy (SEM), transmission electron microscopy (TEM) and temperature programed desorption (TPD-NH₃). The characterization results indicated that V₂O₅ is highly dispersed on alumina up to 30%-V₂O₅/γ-Al₂O₃-MW prepared by MW method. The TPD studies indicated that there are significant differences in acid amount and strength for V₂O₅/γ-Al₂O₃-C and V₂O₅/γ-Al₂O₃-MW-catalysts. The catalytic activity of the prepared catalysts was evaluated in the temperature range 450–600 °C in relation to the physicochemical properties and surface acidity. The results revealed that optimum catalytic activity and selectivity (～100%) toward styrene production were obtained using 10% V₂O₅/γ-Al₂O₃-MW catalyst treated with microwave.     

Laser annealing of capped and uncapped GaAs

Ion-implanted GaAs samples have been annealed using a Q-switched ruby laser. Both Si3N4 capped and uncapped samples decomposed and gallium precipitates were formed at the surface. The gallium could be removed by dissolution in HCl to leave high-quality GaAs.     

Metal-insulator-semiconductor solar cell under gamma irradiation

The performance of a home made MIS–p-Si solar cell was experimentally studied under various gamma irradiation doses (up to 500 Mrad). The effect of radiation dose on the I−V and C−V characteristics was investigated in this work. The obtained results showed that all the output parameters of the cells under investigation were degraded with gamma radiation exposure. In addition, the effects of fabrication conditions (metal thickness and adding of antireflection coating) on the cell output parameters were also investigated.     

The effect of absorber packing height on the performance of a hybrid liquid desiccant system

A hybrid system consisting of vapour compression unit, a liquid desiccant system, and a flat solar hot water collector were designed, fabricated and tested. This combination allowed for a separate control of humidity and temperature without energy penalty. Various packing heights of the absorber component were tested to determine the optimal performance of the combined unit. A 1000 mm packing height with cross-sectional area of 600×600 mm, proved to be the best height that gives promising improvements in the coefficient of performance of the vapour compression unit.     

A stochastic realization approach to the smoothing problem

The purpose of this paper is to develop a theory of smoothing for finite dimensional linear stochastic systems in the context of stochastic realization theory. The basic idea is to embed the given stochastic system in a class of similar systems all having the same output process and the same Kalman-Bucy filter. This class has a lattice structure with a smallest and a largest element; these two elements completely determine the smoothing estimates. This approach enables us to obtain stochastic interpretations of many important smoothing formulas and to explain the relationship between them.     

Synthesis of novel poly 2‐vinylpyridine‐mixed metal complexes and studying their effect as antitumor chemotherapeutic agents,part 2

The poly2‐vinylpyridine and cationic polymer‐mixed metal complexes (P2VPMC) have been prepared and characterized by analytical measurement such as: molecular weight, elemental analysis, IR‐spectroscopy, NMR‐spectroscopy, XRD, and UV. The degree of N‐alkylation of poly vinyl pyridine (P‐2VP) was 10% determined by chlorine content according to elemental microanalysis. Through ICP instrument the complexation between P‐2VPC and the mixed metal chlorides was proven. The structure of the samples was characterized using X‐ray diffraction. It was found that the complexes have amorphous properties. The antitumor activity of this compound was examined in vitro on cell lines. The results reflect pronounced cytotoxicity of P‐2VPMC against animal experimental EAC cells line, and human, HeLa, HCT116 and Hep‐G2, cell lines. Antitumor activity of the novel compound as applied on mice bearing Ehrlich solid carcinoma, revealed delays tumor growth compared with untreated animals and decreases tumor volume. The antitumor activity of the P2VPMC might be due to its ability to pass through the membrane and interact with, DNA causing cross‐linking action which might be the key factor for great antitumor activity of the P2VPMC compound. © 2010 Wiley Periodicals, Inc. J Appl Polym Sci, 2010