Investigation of the morphology of polypropylene − nanoclay nanocomposites

The morphology development in polypropylene ? nanoclay composites with different weight percentages of nanoclay additives was studied using a combination of wide‐angle X‐ray diffraction, small‐angle X‐ray scattering (SAXS), polarized optical microscopy and transmission electron microscopy. SAXS studies showed an increase in long period with increase in additive weight percentage. Thermal analysis showed that even if the clay platelets are not completely exfoliated they can act as effective nucleating agents. Studies indicated that the ultimate morphology formation is influenced by both the thermodynamics of mixing and crystallization and spherulite formation. During spherulite growth, unenclosed clay platelets were excluded at the spherulite boundaries. From the observed results, a schematic model of morphology formation in polypropylene ? nanoclay composites is proposed. © 2013 Society of Chemical Industry     

Fe–EBT Chelate Complex: A Novel Mean for Growth of α-FeOOH and γ-Fe_2O_3 Nanostructures

Acicular goethite(a-Fe OOH) and worm-like maghamite(γ-Fe_2O_3) nanostructures have been prepared adopting a novel route, using Na2[Fe(HL)2(H2O)2] chelate complex in alkaline medium. It is found that concentration of hydrated Fe(III) ions increased with increasing temperature, which later play a key role in generation of different phases of iron oxide. Phase and morphology of the products are investigated using XRD, FTIR, SEM, and TEM analysis. Using UV–Vis spectra, various electronic transitions of goethite and maghamite particles are examined. Maghamite nanostructures exhibit superparamagnetic property at room temperature. On the basis of experimental observations and analytical data, growth mechanism of the nanostructures is discussed.     

Rheological properties of washed and unwashed tilapia (<Emphasis Type="Italic">Oreochromis mossambicus</Emphasis>) fish meat: effect of sucrose and sorbitol

In the present study, the dynamic viscoelastic behavior (DVB) and flow behavior of fresh tilapia (Oreochromis mossambicus) meat containing cryoprotectants were evaluated with and without water washing. The DVB profile of washed meat with 4% sucrose and sorbitol indicated the maximum structure buildup reaction up to 56.8 °C; thereafter, hydrophobic interactions leading to decreased gelation were suppressed. In both the samples, there was no clear indication of the sol–gel transition temperature. In flow-profile measurements, the presence of cryoprotectants gave rise to the minimum thixotropic area, indicating a low level of impairment in structure. The shear-stress sweep of water-washed tilapia proteins added with cryoprotectants did not reveal significant changes at 28 and 40 °C. In texture-profile analysis, the hardness values were lower in fresh meat than cooked meat. The findings of this study will be helpful in the formulation and design of various mince-based products and in determining the appropriate use of cryoprotectants and water washing in the processing of minced meat.     

Photoluminescence behavior and visible light photocatalytic activity of ZnO,ZnO/ZnS and ZnO/ZnS/α-Fe2O3 nanocomposites

In order to achieve effective, economic, and easily achievable photocatalyst for the degradation of dye methyl orange (MeO), ZnO, ZnO/ZnS and ZnO/ZnS/α-Fe₂O₃ nanocomposites were prepared by simple chemical synthetic route in the aqueous medium. Phase, crystallinity, surface structure and surface behavior of the synthesized materials were determined by X-ray diffraction (XRD) and Brunauer–Emmett–Teller analysis (BET) techniques. XRD study established formation of good crystalline ZnO, ZnO/ZnS and ZnO/ZnS/α-Fe₂O₃ nanomaterials. By using intensity of constituent peaks in the XRD pattern, the compositions of nanocomposites were determined. From the BET analysis, the prepared materials show mesoporous behavior, type IV curves along with H4 hysteresis. The ZnO/ZnS/α-Fe₂O₃ composite shows the largest surface area among three materials. From the UV–visible spectra, the band gap energy of the materials was determined. Photoluminescence spectra (PL) were used to determine the emission behavior and surface defects in the materials. In PL spectra, the intensity of UV peak of ZnO/ZnS is lowered than that of ZnO while in case of ZnO/ZnS/α-Fe₂O₃, the intensity further decreased. The visible emission spectra of ZnO/ZnS increased compared with ZnO while in ZnO/ZnS/α-Fe₂O₃ it is further increased compared with ZnO/ZnS. The as-synthesized materials were used as photocatalysts for the degradation of dye MeO. The photo-degradation data revealed that the ZnO/ZnS/α-Fe₂O₃ is the best photocatalyst among three specimens for the degradation of dye MeO. The decrease of intensity of UV emission peak and the increase of intensity of visible emission cause the decrease of recombination of electrons and holes which are ultimately responsible for the highest photocatalytic activity of ZnO/ZnS/α-Fe₂O₃.     

Supported NHC-Benzimi@Cu Complex as a Magnetically Separable and Reusable Catalyst for the Multicomponent and Click Synthesis of 1,4-Disubstituted 1,2,3-Triazoles via Huisgen 1,3-Dipolar Cycloaddition

Catalysis Letters - In this paper, we report a novel magnetically separable silica coated copper nano-magnetite NHC-benzimi@Cu complex as heterogeneous catalyst for the multicomponent click...     

Altered signaling associated with chronic arsenic exposure in human skin keratinocytes

Modulation of signaling pathways upon chronic arsenic exposure remains poorly studied. Here, we carried out SILAC‐based quantitative phosphoproteomics analysis to dissect the signaling induced upon chronic arsenic exposure in human skin keratinocyte cell line, HaCaT. We identified 4171 unique phosphosites derived from 2000 proteins. We observed differential phosphorylation of 406 phosphosites (twofold) corresponding to 305 proteins. Several pathways involved in cytoskeleton maintenance and organization were found to be significantly enriched (p<0.05). Our data revealed altered phosphorylation of proteins associated with adherens junction remodeling and actin polymerization. Kinases such as protein kinase C iota type (PRKCI), mitogen‐activated protein kinase kinase kinase 1 (MAP3K1), tyrosine‐protein kinase BAZ1B (BAZ1B) and STE20 like kinase (SLK) were found to be hyperphosphorylated. Our study provides novel insights into signaling perturbations associated with chronic arsenic exposure in human skin keratinocytes. All MS/MS data have been deposited to the ProteomeXchange with identifier PXD004868.     

A Short Review on Utilization of Ferrochromium Slag

The ferrochromium slag is an important by-product of ferrochromium industries. Recycling and efficient utilization of the large volumes of slag generated by ferrochrome production process is a huge challenge for ferrochrome producers. This article reviews ferrochromium slag utilization with reference to refractory, ceramics and construction and other applications. In addition to this the development of crystal phases and the environmental aspects of ferrochromium slag in relation to its utilization are discussed. The crystalline phases evolve during solidification impart unique properties like strength, stability and refractoriness which open its opportunities as an alternative raw material for ceramic, refractory, civil construction. Chemical composition of ferrochromium slag can be altered suitably for application in high temperature refractory ceramic application. The use of ferrochromium slag in building and road making material will relieve some of the burden from natural resources.