Comparative efficiency of maltodextrin and protein in the production of spray-dried tamarind pulp powder

The potential of maltodextrin (DE 20) and soya protein isolate (SPI) in spray drying of tamarind pulp was compared. Powder recovery was zero when the tamarind pulp was spray dried alone. A greater amount of maltodextrin (MD; 55%) was required for successful spray drying of tamarind pulp, whereas a small amount of SPI (20%) was needed for the same purpose. The study revealed that the mechanism for the increase in product recovery with the addition of MD is due to the increase in overall glass transition temperature of tamarind pulp powder. However, using SPI, preferential migration of the protein to the surface of droplets/particles resulting in the formation of a glassy skin was responsible for a reduction in stickiness between the particles and dryer wall and hence increased the powder recovery. The potential of SPI in reducing powder hygroscopicity was almost comparable to that of MD, confirming its efficiency as a drying aid. Tamarind pulp powders produced with SPI had a larger particle size with a wrinkled particle surface morphology and high flowability compared to powders produced with MD. The study showed the excellent potential of SPI as a drying aid in production of quality tamarind pulp powder.     

Cyanidation of Gold Associated with Silver Minerals in Sulfide Mineral Matrices

Lead salt stimulated the dissolution of gold when gold associated with silver minerals was interspersed in the silica or in the pyrite‐silica layer. Gold dissolution was likewise promoted through lead addition for chalcopyrite‐silica and the sphalerite‐silica systems. Lead addition did not boost gold dissolution and a recovery of 6.9 % was achieved for gold and silver minerals dispersed in stibnite. Lead pretreatment also enhanced gold recovery except for the stibnite‐silica system. Gold surface‐passivating films were observed for gold associated with silver minerals and stibnite.     

Experimental investigation of a new type of interfacial instability in a reactive coextrusion process

This paper deals with the study of new interfacial instabilities, called “grainy” defects, in coextrusion process of reactive multilayer polymers. The main objective was to better understand this phenomenon since no help can be found in the literature. The fundamental approach from a micro‐scale to a macro‐scale involves the study of relationships between polymer structure, processing, and interfacial properties. The influence of these parameters on the generation of “grainy” defects during coextrusion has been assessed in correlation with physicochemical properties. Through this work, rheological properties and the interfacial morphology between tie and barrier layers have been investigated by shear stress relaxation experiments and transmission electronic microscopy, respectively. Depending on the reactive polymers, the interfacial coupling was found to significantly alter the stress relaxation behavior by extending the relaxation time and generating an interfacial roughness. Hence, relations between the copolymer architecture, the relaxation process, and the interfacial morphology were established in correlation with the generation of grainy defects in coextrusion process. POLYM. ENG. SCI., 55:2542–2552, 2015. © 2015 Society of Plastics Engineers     

Synthesis of Ferrocene-Based Hyperbranched Polyether and Its Catalytic Performance for Thermal Decomposition of Ammonium Perchlorate

A series of ferrocene-based hyperbranched polyethers (HBPE-Fc) with different ferrocene content were synthesized by esterification of ferrocenecarbonyl chloride and hyperbranched polyether (HBPE). ¹H NMR and FT-IR were used to confirm the structure of HBPE and HBPE-Fc. GPC was used to calculate the molecular weights. The catalytic performance of the synthesized HBPE-Fc for thermal decomposition of ammonium perchlorate (AP) was investigated by TG and DTG techniques. The results showed that HBPE-Fc exhibited good catalytic activity on the thermal decomposition of AP. The influence factors on catalytic performances, such as substitution degree of ferrocene and mass ratio of AP/HBPE-Fc were discussed as well.     

Fluorescent Polyimide Films Produced with Diatomite and Mesoporous Silica as Promising High-Tech Material

Journal of Inorganic and Organometallic Polymers and Materials - Due to their excellent properties, polymides (PIs) result promising as high-performance materials in different technological fields....     

Micro-capacitors based on electrochemically grown vertical arrays of gold nanowires as electrodes

This paper describes the development of micro-capacitors with electrodes based on electrochemically grown vertical gold nanowire arrays. A high aspect-ratio anodized aluminum oxide template integrated on silicon dioxide/silicon substrates was exploited for fabricating a vertical array of nanowires with a high surface to volume ratio. Bismuth ferric oxide thin films were deposited to create high dielectric material between the electrodes using room temperature electrodeposition. This nanofabrication process may be compatible with a complementary metal-oxide-semiconductor (CMOS) process, therefore, this capacitor can be used for protecting and regulating the surge voltage biased to the CMOS circuits. This capacitor achieved a high density capacitance of 3.1 μF/m² at 1 MHz, which was measured using a parallel plate set-up.     

A method for real power transfer allocation using multivariable regression analysis

A multivariable regression (MVR) approach is proposed to identify the real power transfer between generators and loads. Based on solved load flow results, it first uses modified nodal equation method (MNE) to determine real power contribution from each generator to loads. Then, the results of MNE method and load flow information are utilized to determine suitable regression coefficients using MVR model to estimate the power transfer. The 25-bus equivalent system of south Malaysia is utilized as a test system to illustrate the effectiveness of the MVR output compared to that of the MNE method. The error of the estimate of MVR method ranges from 0.001 4 to 0.007 9. Furthermore, when compared to MNE method, MVR method computes generator contribution to loads within 26.40 ms whereas the MNE method takes 360 ms for the calculation of same real power transfer allocation. Therefore, MVR method is more suitable for real time power transfer allocation.     

Biosynthesis of reusable and recyclable CuO@Magnetite@Hen Bone NCs and its antioxidant and antibacterial activities: a highly stable magnetically nanocatalyst for excellent reduction of organic dyes and adsorption of polycyclic aromatic hydrocarbons

For the first time, through a fast, eco‐friendly and economic method, the aqueous extract of the leaf of Euphorbia corollate was used to the green synthesis of the highly stable CuO@Magnetite@Hen Bone nanocomposites (NCs) as a potent antioxidant and antibacterial agent against Pseudomonas aureus, Staphylococcus aureus, Escherichia coli and Klebsiella pneumoniae pathogenic bacteria. The biosynthesised NCs were identified using the scanning electron microscopy (SEM), energy dispersive X‐ray spectroscopy, elemental mapping, X‐ray diffraction (XRD), Fourier transforms infrared spectroscopy and UV–vis analytical techniques. Also, the radical scavenging activity using (2,2‐diphenyl‐1‐picrylhydrazyl) method was used to evaluate the antioxidant activity of the NCs. The stability of nanocatalyst was monitored using the XRD and SEM analyses after 30 days from its synthesis. Furthermore, its excellent catalytic activity, recycling stability, and high substrate applicability were demonstrated to the adsorption of the polycyclic aromatic hydrocarbons of the light crude oil from Shiwashok oil fields and destruction of methylene blue and methyl orange as harmful organic dyes at ambient temperature using UV–vis spectroscopy. Moreover, the green CuO@Magnetite@Hen Bone NCs were recovered and reused several times without considerable loss of its catalytic activity.Inspec keywords: nanobiotechnology, X‐ray diffraction, infrared spectra, catalysis, crude oil, Fourier transform spectra, ultraviolet spectra, scanning electron microscopy, dyes, catalysts, photochemistry, iron compounds, X‐ray chemical analysis, antibacterial activity, adsorption, visible spectra, microorganisms, organic compounds, reduction (chemical), nanomedicine, toxicology, recycling, chemical industryOther keywords: antioxidant activity, XRD, SEM analyses, recycling stability, polycyclic aromatic hydrocarbons, harmful organic dyes, UV–vis spectroscopy, green CuO@Magnetite@Hen Bone NCs, reusable CuO@Magnetite@Hen Bone NCs, recyclable CuO@Magnetite@Hen Bone NCs, antioxidant activities, antibacterial activities, highly stable magnetically nanocatalyst, eco‐friendly method, economic method, euphorbia corollate, green synthesis, CuO@Magnetite@Hen Bone nanocomposites, antibacterial agent, pseudomonas aureus, staphylococcus aureus, escherichia coli, klebsiella pneumoniae pathogenic bacteria, biosynthesised NCs, X‐ray spectroscopy, X‐ray diffraction, radical scavenging activity, antioxidant agent, 2,2‐diphenyl‐1‐picrylhydrazyl, catalytic activity, organic dye reduction, light crude oil, CuO