A compact uniplanar ACS fed multi band low cost printed antenna for modern 2.4/3.5/5 GHz applications

Microsystem Technologies - A uniplanar compact triple operating band asymmetric coplanar strip (ACS) fed printed antenna loaded with multiple L-shaped branches and the asymmetric rectangular ground...     

Effect of composition on steady state and transient photoconductivity in isocoordinated In<Subscript>x</Subscript>Sb<Subscript>30−x</Subscript>Se<Subscript>70</Subscript> (0 ≤ x ≤ 25) chalcogenide films

The study of steady state and transient photocurrent measurement provide important information about carrier generation and recombination phenomena in various semiconducting systems for photo-sensor device applications. In the present work, the composition dependent analysis of photocurrents was studied for thermally evaporated Se-rich In_xSb_30?xSe₇₀ films of average thickness 800 nm. The indirect optical gap has been calculated from the transmission and reflection data and the variation of molecular units was studied from the Raman spectroscopy. The initial rise of photocurrent sharply to approach a steady state value during illumination and fast decay to a constant persistent current after stopping the illumination has been observed. The intensity dependence of photocurrent obeys the power law I_Ph?=?F^γ, where the value of exponent tells about the recombination process. The decay of photocurrent has been fitted with stretched exponential function for different compositions and at different light intensities. These results are important for the development of low cost photo absorbers for solar cell applications and visible region responsive photo sensor devices.     

A clustered locally linear approach on face manifolds for pose estimation

Data points with small variations between them are assumed to lie close to each other on a smooth varying manifold in the feature space. Such data are hard to classify into separate classes . A sequence of face pose images with closely varying pose angles can be considered as such data. The pose angles when large enough create images that are largely differing from each other, and thus, the sequence of face images can be assumed to be on or near a nonlinear manifold. In this paper, we propose an unsupervised pose estimation method for face images based on clustered locally linear manifolds using discriminant analysis. We divide the data into multiple disjointed, locally linear and separable clusters. The problem of identifying which cluster to use is solved by dividing the entire process into two steps. The first step or projection using the entire smooth manifold identifies a rough region of interest. We use clustering techniques on entire data to form the pose-dependent classes which are then used to find the first set of discriminant functions. The second step or second projection uses trained cluster(s) from this neighbourhood to obtain a second set of discriminant functions. The idea behind such an approach is that the local neighbourhood would be linear and provide better between-class separation, and hence, the classification problem would now be simpler.     

Metol as Corrosion Inhibitor for zinc

The inhibition behavior of metol (N-methyl-p-aminophenol sulphate) on zinc in different corrosive solutions at room temperature was investigated by various techniques such as weight loss, polarization and linear polarization methods. The percentage inhibition efficiencies were evaluated at different concentrations of the inhibitors. The corrosion rate, inhibition efficiency and surface coverage were dependent on metol concentration. The electrochemical data indicated a basic modification of zinc surface resulting in a decrease in the corrosion rate. Corrosion inhibition was explained by considering an interaction between metal surface and the inhibitor. SEM images and FT-IR profiles confirmed the formation of passive film on the metal surface.     

Mass housing

Professor Vir Handa's abiding interest in low‐cost housing for the lower‐income earners is demonstrated in his paper from the University of Waterloo, Ontario. He draws experience from time spent at the Building Research Institute, Roorkee, under the United Nations TOKTEN Programme and illustrates his paper with pictures from Trinidad, where he is an External Examiner at the University of the West Indies. He argues that although shelter communities are being built without any government help and without any awareness of any codes and standards, the job of the expert should be to determine new affordable code requirements.     

Low‐Density Open Cellular Silicon Carbide Foams from Sucrose and Silicon Powder

Open cellular SiC foams with low densities were prepared by thermo‐foaming and setting (130°C–150°C) of silicon powder dispersions in molten sucrose followed by pyrolysis and reaction sintering at 1500°C. The bubbles generated in the dispersion by water vapor produced by the –OH condensation was stabilized by the adsorption of silicon particles on the air‐molten sucrose interface. The composition of a sucrose‐silicon powder mixture for producing SiC foam without considerable unreacted carbon was optimized. The sucrose in the thermo‐foamed silicon powder dispersion leaves 24 wt% carbon during the pyrolysis. The sintering additives such as alumina and yttria promoted the silicon‐carbon reaction. SiC nanowires with diameters in the range of 35–55 nm and length >10 μm observed on the cell walls as well as in the fractured strut region were grown by both vapor–liquid–solid and vapor–solid mechanisms. Large SiC foam bodies without crack could be prepared as the total shrinkage during pyrolysis and reaction sintering was only ~30 vol%. The relatively low compressive strength (0.06–0.41 MPa) and Young's modulus (14.9–24.2 MPa) observed was due to the large cell size (1.1–1.6 mm) and high porosity (93%–96%).     

Analysis of the Disintegration of Distiller's Spent Grain Compacts as Affected by Drying in Superheated Steam

Breaking and disintegrating of biomass compacts while they are being dried in superheated steam (SS) is a common problem observed during the initial stage of SS drying. The present work investigated the moisture and temperature changes, volume and density variation, crushing resistance, and tensile strength of single cylindrical compacts produced from wet distiller's spent grain (WDG) under SS drying conditions. The wet compacts were dried in SS at 110, 130, and 150°C with SS velocities of 0.9, 1.1, and 1.4 m/s. For a specific temperature and velocity, the compacts were exposed to SS for time periods of 5, 120, 300, and 600 s and the changes in physical properties were analyzed. An increase in a percentage increase in volume by 78–130% and a decrease in density by 51–61% were observed as a result of drying the compact in SS. The results obtained from the study were compared with hot-air dried compacts for 600 s, indicating that SS drying had a substantial role in stimulating the relaxation of stresses stored in the compacts as compared with a convection hot-air drying process.     

Intracavernous Injection of Platelet-Rich Plasma Therapy Enhances Erectile Function and Decreases the Mortality Rate in Streptozotocin-Induced Diabetic Rats

Erectile dysfunction (ED) is an agonizing complication of diabetes mellitus (DM) and it is challenging to treat ED in DM patients. Platelet-rich plasma (PRP) is a unique therapeutic strategy comprising intrinsic growth factors. An attempt was made to explore the potentiality of the PRP treatment in DM-induced ED rats in various groups (control, DM-non-ED, DM-ED, and DM-ED treated with PRP). Streptozotocin (STZ) was used to induce DM in rats. The blood glucose levels of the DM rats were maintained at >300 mg/dl. In the 18-week experiment, survival rate, body weight, intracavernous pressure (ICP) variations, and arterial blood pressure were analyzed. The tissue restoration results were validated by histological, immunofluorescence, and transmission electron microscopic analysis. PRP treatment of DM-ED rats significantly increased all parameters of erectile function compared to pre-treatment of PRP and DM-ED treated with vehicle. The histological results revealed that PRP treatment substantially enhanced the regeneration of myelinated nerves and decreased the atrophy of corporal smooth muscle. Notably, the PRP treatment immensely enhanced the survival rate in post-surgery DM-ED rats. These results indicated certain benefits of PRP treatment in delaying damage and preventing post-surgery complications in DM patients. Hence, PRP treatment is a novel multifactorial strategy for DM-ED patients.