Investigations on the Influence of Liquid-Assisted Laser Ablation of NiTi Rotating Target to Improve the Formation Efficiency of Spherical Alloyed NiTi Nanoparticles

In this work, the liquid-assisted laser ablation of NiTi rotating target has been used as a promising technique for generating spherical NiTi alloy nanoparticles with higher formation efficiency. Nd: YAG nanosecond laser with three different laser wavelengths (355, 532 and 1064 nm), three different laser fluences (30, 40 and 50 J/cm²) and three different rotational speeds (10 RPM, 20 RPM and 30 RPM) of target has been used to ablate the nitinol (Ni-55%, Ti-45%) target. The influences of different laser parameters (wavelengths and fluences) and different RPMs have been studied on the size, morphology and formation of alloy nanoparticles. It has been observed that the formation efficiency is maximum (39.9 mg/h) for smaller size nanoparticle (~40 nm) at 355 nm wavelength, 50 J/cm² fluence and 10 RPM rotational speed. On the other hand, we find that the formation efficiency (10.5 mg/h) is lowest with a bigger size of nanoparticle (~110 nm) at 1064 nm wavelength, 50 J/cm² fluence and 30 RPM speed. Therefore, this is a promising technique to synthesize spherical alloy nanoparticles with higher ablation efficiency. Thus, the higher ablation of particles helps to improve the optical absorption of the colloidal solution as optical absorption has a direct relation with the particle concentration. The shape and size of particles were characterized through SEM and DLS analysis whereas the crystallinity was confirmed through TEM and XRD analysis, respectively. Moreover, the elemental analysis was done with the help of XPS and EDS and optical absorption through UV–Vis spectrum analysis.     

Efficient shadow detection by using PSO segmentation and region-based boundary detection technique

The Journal of Supercomputing - The presence of shadows in satellite images is inevitable, and hence, shadow detection and removal has become very essential. In this paper, a shadow detection...     

Homeopathic remedy for arsenic toxicity?: Evidence-based findings from a randomized placebo-controlled double blind human trial

Millions of people are at risk of groundwater arsenic contamination, but supply of arsenic-free drinking water is grossly inadequate. The present study was intended to examine if a potentized homeopathic remedy reportedly showing ameliorating potentials in people inhabiting high-risk arsenic-contaminated areas but drinking arsenic-free water, can also ameliorate arsenic toxicity in subjects living in high-risk arsenic-contaminated areas, and drinking arsenic-contaminated water. This pilot study was conducted on 20 males and 19 females of village Dasdiya (arsenic contaminated) who initially agreed to act as volunteers; but as many as 14, mostly placebo-fed subjects, later dropped out. 18 volunteers, 14 males and 4 females, from a distant village, Padumbasan (arsenic-free), served as negative controls. In a double blind placebo-controlled study, a potentized remedy of homeopathic Arsenicum Album-30 and its placebo (Succussed Alcohol-30) were given randomly to volunteers. Arsenic contents in urine and blood and several widely accepted toxicity biomarkers and pathological parameters in blood were analyzed before and after 2 months of administration of either verum or placebo. Elevated levels of ESR, creatinine and eosinophils and increased activities of AST, ALT, LPO and GGT were recorded in arsenic exposed subjects. Decreased levels of hemoglobin, PCV, neutrophil percentages, and GSH content and low G-6-PD activity were also observed in the arsenic exposed people. The administration of "verum" appeared to make positive modulations of these parameters, suggestive of its ameliorative potentials. Most of the subjects reported better appetite and improvement in general health, thereby indicating possibility of its use in remote arsenic-contaminated areas as an interim health support measure to a large population at risk.     

Polarization phase-shifting interferometric technique for complete evaluation of birefringence

A full-field technique for simultaneous measurement of the magnitude of birefringence and its orientation is presented. This is achieved using a monolithic birefringence sensitive interferometer where the interference fringes carry the information of both the birefringence phase and the orientation of the fast axis of an optically transmissive anisotropic material placed at the output of the interferometer. The interferometer consists of a suitably polarization-masked cube beam splitter, orientated as in the Gates interferometer, which serves to generate a pair of orthogonally polarized and collinearly propagating light beams. Experimental results are obtained through an algorithm incorporating eight polarization phase-shifted interferograms.     

Thermal degradation characteristics of poly[poly(ethylene glycol)] phosphates

Thermal degradation characteristics of some poly[poly(ethylene glycol)] phosphates (PPEGP) based on ethylene glycol (PEGP), an equimolar mixture of ethylene glycol and trigol (PETP), digol (PDGP), and trigol (PTGP) have been studied by combined differential thermal and thermogravimetric analyses (DTA/TGA). It has been shown that, in spite of their structural similarities, the PPEGPs do not conform to any generalized degradation pattern. Local strains in the crosslinked network and the possible intranetwork topographic interferences due to crossovers, entanglements, and varying lengths of polyoxyethylene link units are believed to play a pivotal role in the thermal degradation of individual PPEGPs. © 1995 John Wiley & Sons, Inc.     

Sm and Sr co-doped ceria prepared by citrate–nitrate auto-combustion method

A few compositions in the system, Ce_{1 − x − y}Sm_xSr_yO_1.90 have been prepared by citrate–nitrate auto-combustion method. X-ray diffraction data show that all the compositions are solid solution having cubic fluorite structure. Density of the samples sintered at 1350 °C has been found to be more than 95% of the theoretical value. Surface morphology has been studied by scanning electron microscope. AC impedance spectroscopy measurements have been carried out to study the grains, grain boundaries and total ionic conductivity of the samples in the temperature range 200–600 °C. The composition, Ce_0.82Sm_0.16Sr_0.02O_1.90 shows the maximum conductivity i.e. 2.67 × 10⁻² S-cm⁻¹ at 600 °C among all the compositions investigated. This is about two times higher than that of Ce_0.80Sm_0.20O_1.90.