Sulfonated co-poly(ether imide)s with alkyne groups: Fabrication of crosslinked membranes and studies on PEM properties including MFC performance

A new diamine monomer having alkyne side-groups (DADAF) has been successfully synthesized, and it was used to prepare a series of sulfonated co-polyimides (DFN-XX) when reacted with 1,4,5,8-naphthalenetetracarboxylic dianhydride along with different mole% of 4,4′-diaminostilbene-2,2′-disulfonic acid. The membrane was made from the copolymers by solution casting route, and one of the copolymers DFN-70 was used to prepare crosslinked membranes by adding a different amount of 1,6-hexanediazide during solution casting step. The morphological transformation from non-crosslinked S-coPI to crosslinked S-coPI was observed by employing transmission electron microscopy, atomic force microscopy, and small-angle X-ray scattering analyses. Compared to the non-crosslinked DFN-XX membranes, crosslinked DFN-70 copolymer membranes showed low water uptake and improved mechanical and peroxide radical stability. Also, crosslinked DFN-70 copolymer membranes showed significantly higher proton conductivities (0.004-0.06 S cm⁻¹) compared to those of DFN-70 (0.003-0.05 S cm⁻¹) particularly, at 80°C when the relative humidity increased from 40% to 98%. Furthermore, crosslinked DFN-70 copolymer membranes exhibited significantly enhanced performance in a microbial fuel cell (MFC) as compared to those of non-crosslinked DFN-70 membrane.     

Variations of Slot Cut and Stub Loaded Square Microstrip Antenna for Circular Polarization

Wireless Personal Communications - Modified technique to produce circular polarization for square, nearly square microstrip antenna using diagonal slots of different shapes, slits, stub at corners...     

Effect of complexing agents: investigations on structural,morphological, topographical and optical analysis of copper iron sulphide thin films deposited by chemical bath deposition method

Copper iron sulphide (FeCuS₂) thin films deposited by chemical bath deposition method using ferrous sulphate and copper sulphate as cationic sources and sodium sulphide as anionic source with complexing agents, EDTA and Leishman stain were reported. The structural, optical and morphological studies were carried out using X-ray diffraction, scanning electron microscopy (SEM), atomic force microscopy (AFM) and UV–Visible spectroscopy techniques. The X-ray spectrum reveals that the films are polycrystalline nature and also showed the deposition of cubic phases at room temperature. The SEM images for prepared films have clear morphology influenced by the complexing agents used in deposition process. The result of AFM studies shown that the particles in the film have grain size around ~?60–70 nm and also have almost similar thickness. Based on the optical absorbance spectra the FeCuS₂ film exhibited a high absorbance in the visible region. The absorption edge shifted toward lower wavelength with varying complexing agents. The band gap value obtained was found to be 3.57–3.85 eV. From these results, it is indicated that the prepared films are suitable candidate for solar cell applications.     

Detection of Choroidal Neovascularization (CNV) in Retina OCT Images Using VGG16 and DenseNet CNN

Wireless Personal Communications - In this study, we intend to diagnose Choroidal Neovascularization in retinal Optical Coherence Tomography (OCT) images using Deep Learning Architectures. OCT...     

A refined model for the mechanical properties of polymer composites with nanorods having different length distributions

The aspect ratio of rod‐like nanofillers is an important factor that governs their percolation threshold in nanocomposites with a polymer of interest. Controlling the length distribution of a filler is an effective way to manipulate the onset of network formation and thereby materials properties that are related to the latter. The use of two or more different filler types with dissimilar aspect ratio is a special case to achieve such control. We here report the modification of an existing mechanical model to describe the mechanical properties of polymer nanocomposites with a binary length distribution of nanofillers. The model was exemplarily applied to materials comprised of two nanorod types having high and low aspect ratio, respectively, and used to explain why the properties of such nanocomposites are strongly weighted by the nanorod type characterized by a higher aspect ratio and stiffness. © 2017 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2017 , 134, 45279.     

MWCNT-Modified Gold Electrode Sensor for the Determination of Propyl Gallate in Vegetable Oils

A differential pulse voltammetric method for the determination of the synthetic food antioxidant, propyl gallate (PG) was developed. Determination of PG was carried out using multiwalled carbon nanotube (MWCNT)-modified gold electrode (GE) in a solution of 0.1 M acetate buffer (pH 7) as supporting electrolyte. The developed sensor showed an excellent catalytic activity and stability for PG oxidation. Effect of common interfering ions, amount of MWCNT–Nafion suspension, pH of the supporting electrolyte, and scan rate were studied. Under optimized conditions, PG concentration as low as 6.3?×?10^?7 M can be determined in food samples. The determination of PG in vegetable oils with the proposed sensor was in good agreement with those obtained by reported spectrophotometric method.     

Test Data Volume Comparison: Monolithic vs. Modular SoC Testing

Editor's note:Containing production cost is a major concern for today's complex SoCs. One of the key contributors to production cost is test time and test data volume, for which numerous compression techniques were proposed. This article introduces a different approach to test data volume reduction, namely the use of modular test based on IEEE Std 1500 architecture, and it provides modeling, analysis, and quantification to support the proposed approach.—Yervant Zorian, VirageLogic     

Effects on spermatogenesis in swiss mice of a protein isolated from the roots of Ricinus communis (Linn.) (Euphorbiaceae)

This study was aimed to evaluate the effect on spermatogenesis of a 62 kDa protein (Rp) isolated from 50% ethanolic extract of the root of Ricinus communis in mice. A dose response study in mice revealed that 25mg/kg body weight/day was the most effective dose. Swiss strain mature male mice of 30 days old were divided into two group namely control and Rp treated (25mg/kg body weight/day). The study showed that sperm motility and count were decreased significantly in the treated group as compared to the control. The fertility index of the treated groups was reduced by 100%. The activity of HMG Co A reductase and cholesterol were increased significantly in the treated group. The testicular activities of 3βHSD, 17βHSD, glucose 6-phosphate dehydrogenase and malic enzyme and the level of serum testosterone were decreased significantly in the treated group. The expression of 3βHSD and 17βHSD were decreased and the expression of StAR increased significantly in the treated group as compared to the control. Proteolytic digestion of the native protein with trypsin and chymotrypsin showed that the proteolytic cleavage did not affect the spermicidal action of Rp. Hence this study can be concluded that Rp impaired spermatogenesis in vivo by suppressing the production of testosterone.     

Urbanisation, poverty and sexual behaviour: the tale of five African cities

The question of how urbanisation and poverty are linked in sub-Saharan Africa is an increasingly pressing one. The urban character of the HIV epidemic in sub-Saharan Africa exacerbates concern about the urbanisation - poverty relationship. Recent empirical work has linked urban poverty, and particularly slum residence, to risky sexual behaviour in Kenya's capital city, Nairobi. This paper explores the generalisability of these assertions about the relationship between urban poverty and sexual behaviour using Demographic and Health Survey data from five African cities: Accra (Ghana), Dar-es-Salaam (Tanzania), Harare (Zimbabwe), Kampala (Uganda) and Nairobi (Kenya). The study affirms that, although risky behaviour varies across the five cities, slum residents demonstrate riskier sexual behaviour compared with non-slum residents. There is earlier sexual debut, lower condom usage and more multiple sexual partners among women residing in slum households regardless of setting, suggesting a relatively uniform effect of urban poverty on sexual risk behaviour.