Hypocholesterolemic activity of nut shell extract of Semecarpus anacardium (Bhilawa) in cholesterol fed rabbits

In 60 patients with non-seminomatous testicular germ cell tumours in clinical stages I, IIa and IIb inguinal orchiectomy was performed as primary treatment, followed by modified retroperitoneal lymphadenectomy (RLA). In stage II disease chemotherapy was given in addition. After a follow-up period of at least 24 months only 5% of the patients showed progression of disease. Normal ejaculatory function was preserved in 88% of our patients. Modified RLA seems to be a safe procedure with an acceptably low rate of complications not only in stage I disease, but also in metastatic stages IIa and IIb.     

Effect of Size,Content and Shape of Reinforcements on the Behavior of Metal Matrix Composites (MMCs) Under Tension

Journal of Materials Engineering and Performance - The objective of this research was to investigate the mechanical behavior of metal matrix composites (MMCs) 6061 aluminum, reinforced with silicon...     

Theoretical calculation of hydrogen desorption energies of calcium hydride clusters

Recently calcium hydride has attracted attention as a possible component in ternary complex hydrides such as Ca(AlH₄)₂, Ca₂SiH_x and quaternary complex hydrides of the type Li–B–Ca–H. Although in bulk form CaH₂ decomposes reversibly above 600° centigrade we were motivated to see whether calcium hydride in cluster form has properties suitable for hydrogen storage. We report here the results of DFT calculations using VASP^® package for clusters Ca_nH_2n with n = 1, 2, 3, 4, 6, 8, 10, 12, 14, 16, 20 to get the ground state geometries, energies, bond lengths, and desorption energies, after molecular dynamics optimization. The desorption energy vs. cluster size n curve showed that the desorption energy goes up sharply to ∼1.4 eV per H₂ for n up to 4, followed by a broad maximum of ∼1.8 eV per H₂ around n = 12–14, and then tapers off to a nearly constant value of 1.6 eV per H₂ approximating bulk behavior, which compares favorably with previously reported results. Comparison of these results with those of Mg_nH_2n shows that Ca_nH_2n has a lesser potential as a hydrogen storage medium.     

Investigations on hydrogenated amorphous silicon films grown at high rate in a UHV plasma CVD system

In this paper we analyze the results of an extensive characterisation study involving scanning electron microscopy, spectroscopic ellipsometry, Laser Raman spectroscopy, optical band gap, dark and photoconductivity measurements as a function of temperature and light intensity, current-voltage characteristics and capacitance versus frequency measurements on Schottky diodes of a-Si:H films, prepared in a UHV plasma CVD system at varying deposition rates upto ≈ 10.0 Å/s. We find that the values of imaginary part of the dielectric constant (ε_2max), dark and photoconductivity, activation energy, conductivity pre-exponential factor, exponent Λ of photoconductivity decrease, whereas the values of diode quality factor n and density of defect states increase and the values of the width of TO-peak in Raman spectra, photosensitivity and optical band gap do not change significantly with the increasing rate of deposition. The less severe deterioration of opto-electronic properties observed in these films, even when grown at high rates in our plasma CVD reactors, is attributed to the effective control of secondary plasma reactions in the interelectrode space when kept very low (10–12 mm). Implications of obtaining high growth rate for i-layer, in a p-i-n solar cell structure, is discussed with the available results of modelling analysis.     

Simulation studies on photovoltaic response of ultrathin CuSb(S/Se)2 ternary compound semiconductors absorber-based single junction solar cells

Copper-based ternary CuSb(S/Se)₂ compound semiconductors are showing promise for ultrathin photovoltaic devices. The high absorption coefficient of these semiconductors makes them suitable for very thin absorber, where maximum absorption can be achieved in a photovoltaic device with only nanometers thick CuSb(S/Se)₂ based thin films. The device structure under consideration consists of AZO/i-ZnO/n-CdS/absorber layer/back contact, as the constituent material layers. The device structure is simulated using one dimensional solar cell capacitance simulator (SCAPS 1D) under one sun illumination and considering flat band approximation for the back contact and CuSb(S/Se)₂ interface. The optimized single junction device efficiencies are approximately 14% and approximately 10.18% with CuSbS₂ and CuSbSe₂ absorbers, respectively. Further, the impact of various material parameters such as thickness, acceptor concentration of bulk absorber layer, donor concentration of CdS buffer layer, and defects present at bulk absorber layer and at the buffer/absorber interface is discussed in correlation with the photovoltaic performance of the considered devices. The bandgap of CuSb(S/Se)₂ reduces linearly with Se alloying, and their impact on device performance is quantified in terms of capacitance voltage (CV), capacitance frequency (Cf), and impedance spectra of the photovoltaic device.     

Integral method of analysis of fischer-tropsch synthesis reactions in a catalyst pellet

A generalized integral method is developed to analyze complex reactions in a catalyst pellet. This method is valid for any kinetics and takes into account both internal and external heat and mass transfer effects. The integral equations are solved for a Fischer-Tropsch kinetic model to obtain effectiveness factors. Isothermal multiplicities are observed for low values of the surface coverage parameter α(α = 1/K₁p_co,0), and low values of the parameter σ₂₁ (ratio of Thiele moduli for H₂ and CO). The effectiveness factor is mildly sensitive to the external resistances.     

Challenges in Model Development for Meat Composition Using Multipoint NIR Spectroscopy from At‐Line to In‐Line Monitoring

This study evaluates the efficiency of multipoint near‐infrared spectroscopy (NIRS) to predict the fat and moisture content of minced beef samples both in at‐line and on‐line modes. Additionally, it aims at identifying the obstacles that can be encountered in the path of performing in‐line monitoring. Near‐infrared (NIR) reflectance spectra of minced beef samples were collected using an NIR spectrophotometer, employing a Fabry‐Perot interferometer. Partial least squares regression (PLSR) models based on reference values from proximate analysis yielded calibration coefficients of determination of 0.96 for both fat and moisture. For an independent batch of samples, fat was estimated with a prediction coefficient of determination of 0.87 and 0.82 for the samples in at‐line and on‐line modes, respectively. All the models were found to have good prediction accuracy; however, a higher bias was observed for predictions under on‐line mode. Overall results from this study illustrate that multipoint NIR systems combined with multivariate analysis has potential as a process analytical technology (PAT) tool for monitoring process parameters such as fat and moisture in the meat industry, providing real‐time spectral and spatial information.     

Effects of Ti-based catalysts and synergistic effect of SWCNTs-TiF3 on hydrogen uptake and release from MgH2

The present investigations are focused on the effect of different Ti-based catalysts (Ti, TiO₂, TiCl₃ and TiF₃) on de/re-hydrogenation characteristics of nanocrystalline MgH₂. Desorption temperature of milled MgH₂ lowers from 380 to 350, 340, 310 and 260 °C with the addition of Ti, TiO_2, TiCl₃ and TiF₃ respectively. The rehydrogenation characteristics are also improved through the deployment of Ti-based catalysts. Among all Ti based additives, TiF₃ is found to be the most effective catalyst for hydrogen sorption from nano MgH₂. The better catalytic effect of TiF₃ over other Ti-based catalyst can be explained on the basis of temperature programmed reduction (TPR) studies. TPR experiments performed for different Ti additives, reveals that there is no oxidation/reduction reaction below 400 °C except for TiF₃. The TPR profile of TiF₃ shows some oxidation/reduction reaction exhibits at 200 °C. In order to further improve the sorption characteristics and cyclability of TiF₃ catalyzed nano MgH₂, we have investigated the effect of SWCNTs in MgH₂+TiF₃ sample. De/rehydrogenation characteristics reveal the synergistic effect of SWCNTs and TiF₃ in MgH₂+TiF₃ sample. The details of the improvement in sorption behavior of MgH₂–TiF₃ in presence of SWCNTs are described and discussed.     

Bioremediation potential of genus Portulaca L. collected from industrial areas in Vadodara, Gujarat, India

During the present study, two species of Portulaca, i.e., P. tuberosa and P. oleracea were collected from two field sites in Vadodara, Gujarat, India; one irrigated with industrial effluent and other with tube well water, and were analyzed for heavy metal accumulation in different plant parts viz., roots, stem, leaves, and flowers. Plants collected from effluent irrigated areas showed high accumulation of all the investigated heavy metals in all plant parts with the maximum being in roots and the least in flowers. Interestingly, both species of Portulaca demonstrated hyperaccumulation of multiple elements viz., Cu, Ni, Hg, and Pb. The total shoot concentrations (μg g⁻¹ dw) of Cu, Ni, Hg, and Pb in P. tuberosa were 1538, 1191, 789, and 2744, respectively, while in P. oleracea, these were 1940, 1542, 534, and 2312, respectively. Besides this, selective hyperaccumulation of Se (2,327 μg g⁻¹ dw) and Al (1,164 μg g⁻¹ dw) was shown by P. tuberosa and P. oleracea, respectively. Total shoot concentrations (μg g⁻¹ dw) of Mo were about 399 and 668 in P. tuberosa and P. oleracea, respectively. Overall, P. oleracea accumulated higher amounts of multiple metals from industrial effluent contaminated site, hence appears to be a suitable candidate for phytoremediation purposes of metal contaminated areas.     

Correction to: Wideband Antipodal Vivaldi Antenna Using Metamaterial for Micrometer and Millimeter Wave Applications

Journal of Infrared, Millimeter, and Terahertz Waves -