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In this paper we describe the system design and capabilities of the Australian Square Kilometre Array Pathfinder (ASKAP) radio telescope at the conclusion of its construction project and commencement of science operations. ASKAP is one of the first radio telescopes to deploy phased array feed (PAF) technology on a large scale, giving it an instantaneous field of view that covers 31 square degrees at 800 MHz. As a two-dimensional array of 36x12m antennas, with baselines ranging from 22m to 6km, ASKAP also has excellent snapshot imaging capability and 10 arcsecond resolution. This, combined with 288 MHz of instantaneous bandwidth and a unique third axis of rotation on each antenna, gives ASKAP the capability to create high dynamic range images of large sky areas very quickly. It is an excellent telescope for surveys between 700 MHz and 1800 MHz and is expected to facilitate great advances in our understanding of galaxy formation, cosmology and radio transients while opening new parameter space for discovery of the unknown., 38 pages, 24 figures, accepted for publication in PASA

We present the data and initial results from the first Pilot Survey of the Evolutionary Map of the Universe (EMU), observed at 944 MHz with the Australian Square Kilometre Array Pathfinder (ASKAP) telescope. The survey covers 270 \sqdeg of an area covered by the Dark Energy Survey, reaching a depth of 25--30 \ujybm\ rms at a spatial resolution of $\sim$ 11--18 arcsec, resulting in a catalogue of $\sim$ 220,000 sources, of which $\sim$ 180,000 are single-component sources. Here we present the catalogue of single-component sources, together with (where available) optical and infrared cross-identifications, classifications, and redshifts. This survey explores a new region of parameter space compared to previous surveys. Specifically, the EMU Pilot Survey has a high density of sources, and also a high sensitivity to low surface-brightness emission. These properties result in the detection of types of sources that were rarely seen in or absent from previous surveys. We present some of these new results here., Accepted by PASA

We have found a class of circular radio objects in the Evolutionary Map of the Universe Pilot Survey, using the Australian Square Kilometre Array Pathfinder telescope. The objects appear in radio images as circular edge-brightened discs, about one arcmin diameter, that are unlike other objects previously reported in the literature. We explore several possible mechanisms that might cause these objects, but none seems to be a compelling explanation., Accepted for publication by PASA

We investigate the effect of spatially correlated disorder on the Anderson transition of phonons in three dimensions using a Greens function based approach, namely, the typical medium dynamical cluster approximation (TMDCA), in mass-disordered systems. We numerically demonstrate that correlated disorder with pairwise correlations mitigates the localization of the vibrational modes. A correlation driven localization-delocalization transition can emerge in a three-dimensional disordered system with an increase in the strength of correlations.

Mass distribution of fission products has been determined in $$\upalpha +^{\mathrm {232}}\hbox {Th}$$ reaction at $$E_{\mathrm {lab}}=36.2$$ MeV using $$\upalpha $$ particles from the cyclotron at the Variable Energy Cyclotron Centre (VECC), Kolkata. Yields of 64 fission products having half-lives in the range of about $$\sim 1$$ min to several days have been measured using gamma ray spectrometry. The mass distribution shows a clear triple humped structure indicating the contribution from both asymmetric and symmetric modes of fission. The experimental mass distribution was well reproduced by the calculation from the GEF code, which takes into account the multi-chance fission.

Boron is an important element in nuclear reactor technology due to its high neutron absorption cross section of

In 2016, the District Department of Transportation (DDOT) deployed transit signal priority (TSP) at 195 intersections in highly urbanized areas of Washington, D.C. Years before deployment, DDOT out...

This paper illustrates the potential of unicellular microalgae in electricity production in concurrence with wastewater treatment. Our study focused on the isolation of microalgal strains from various aquatic sources. Cyclic voltammetry was performed to detect the electrogenic activity and out of 18 algal isolates, six algal strains were screened. Coelastrella sp. from the paddy field revealed the well-defined redox peak and its analyzed EPS production was 13.79 mg/ml which paves way to hydrated biofilm matrix assisting in better electrogenicity. Its potential to remove nutrients in wastewater was assessed under lab-scale race way pond. Significant decrease in N, P, BOD, COD, and TOC was observed. The removal efficiency of NH4-N, NO3-N, P, BOD, COD and TOC were 90.38, 90.24, 66.75, 67.15, 69.44, and 83.51 respectively. To the best of our knowledge, EPS production, electrogenic activity and their utility in waste water treatment are reported for the first time in Coelastrella sp.

Boron based refractory materials such as boron carbide (natural and enriched), titanium based boron composites and borides of Zr, La and Ce are important neutron absorber materials for nuclear power reactors as control/shut-off rod and/or shielding materials. As a part of chemical quality control (CQC), it is essential to ascertain the mass fraction of boron as well as its isotopic composition (IC) in these materials by a suitable analytical method. In the present work, these materials have been analysed by Particle Induced Gamma-ray Emission (PIGE) using a 4 MeV proton beam from the Folded Tandem Ion Accelerator (FOTIA) at BARC, Mumbai, for simultaneous determination of the IC (10B/11B atom ratio) and total boron mass fraction determination. For total boron mass fraction determination an in situ current normalized PIGE method was used, with fluorine as the current normalizer. As a part of quality assurance, the IC of boron was determined by Thermal Ionization Mass Spectrometry (TIMS) and the total boron mass fraction was determined by a conventional titrimetry method. The results obtained by the PIGE method, its advantages and a comparison of the results obtained using the two conventional analytical methods are discussed in this paper.

The present work reports the microscopic details of anatase (A) to rutile (R) phase transformation in a Mn-doped TiO2 system. Titanium dioxide (TiO2) powder was synthesized at three different dopant percentages, namely 1, 5, and 10 atom% of Mn, by a coprecipitation technique. Time differential perturbed angular correlation (TDPAC) spectroscopy was used to identify the formation of the rutile-like phase (R*) during the phase-transition process and revealed interface nucleation to be promoted by the Mn dopant. Electron paramagnetic resonance (EPR) spectroscopy, synchrotron-based X-ray absorption near edge structure (XANES), and extended X-ray absorption fine structure (EXAFS) studies showed that Mn exhibited a mixed valence states of 2+ and 4+ at different stages of the annealing process. The rutile onset temperature gradually decreased with the increase in the Mn content. The present report proposes the mechanism for the phase transformation and details the effect of Mn on the A to R phase-transformation process. This can assist in gaining a fundamental understanding of the A to R phase-transformation process and the role of the dopant in stabilizing one phase over the other.

Excitation functions of 66,67Ga and 65Zn, generally used for beam intensity monitoring and/or beam energy determination; 57Co and 58Co produced by natCu(α,x) reactions were measured from their respective thresholds up to 50 MeV using standard stacked foil activation technique followed by high resolution gamma ray spectrometric method. Thick target yields were calculated for these radionuclides using the experimentally determined cross sections and stopping power of natural Cu. Experimentally obtained results were compared with the recently published data, IAEA recommended data and TENDL-2019 data based on the TALYS-1.95 code. The present data are found to be in good agreement with the literature data within experimental uncertainties.

Purpose: To evaluate the visual outcome and complication profile after glued intraocular lens (IOL) in post uveitic eyes. Methods: Patients with history of uveitis who had glued IOL with 3 months antecedent quiet anterior chamber (AC) were included in this prospective observational case series. Visual acuity, slit-lamp examination, fundus evaluation, optical coherence tomography, intraocular pressure, specular count and AC inflammation were analyzed before and after glued IOL procedure. Glued IOL eyes were also compared with their fellow normal capsular bag IOL. Results: Overall 17 eyes (50.7 ± 16.1 years) were analyzed. It included 41.8%, 23.5%, and 35.29% anterior, posterior, and pan uveitis, respectively. The etiologies were tuberculosis (23.53%), toxoplasmosis (11.77%), Fuch's heterochromic cyclitis (5.88%), HLA B27 (11.77%), psoriatic arthritis (5.88%), Rheumatoid arthritis (5.8%), sarcoidosis (11.77%), herpetic kerato-uveitis (5.88%), and idiopathic (17.65%). Cataractous subluxated lens (35.3%), aphakia (23.5%), decentered IOL (23.5%) and intraoperative capsular rupture (17.6%) were the surgical indications. A significant improvement in the mean uncorrected and best corrected visual acuity (P < 0.001) was recorded. The complications were IOL pigment dispersion (47%), macular edema (41%), and epiretinal membrane (24%). There was significant rise in AC reaction on day 1 (P < 0.001) and normal AC was attained by 88.2% eyes at 6 months. AC inflammation reactivation was noted in 11.7% of eyes. Though inflammatory reactivation was similar to the normal IOL, macular edema was higher in glued IOL. Conclusion: Glued IOL can cause inflammation in uveitis eyes which can be managed medically with minimal complications.

Due to technical constraints this article was published in volume 240:1 with erroneous article citation ID number 8 whereas this should have been 78 which is corrected as such. Springer Nature sincerely apologizes towards the author(s) for the inconvenience caused.

We have observed the G23 field of the Galaxy And Mass Assembly (GAMA) survey using the Australian Square Kilometre Array Pathfinder (ASKAP) in its commissioning phase, to validate the performance of the telescope and to characterize the detected galaxy populations. This observation covers $\sim$48 deg$^2$ with synthesized beam of 32.7$^{\prime\prime}$ by 17.8$^{\prime\prime}$ at 936 MHz, and $\sim$39 deg$^2$ with synthesized beam of 15.8$^{\prime\prime}$ by 12.0$^{\prime\prime}$ at 1320 MHz. At both frequencies, the r.m.s. (root-mean-square) noise is $\sim$0.1 mJy/beam. We combine these radio observations with the GAMA galaxy data, which includes spectroscopy of galaxies that are i-band selected with a magnitude limit of 19.2. Wide-field Infrared Survey Explorer (WISE) infrared (IR) photometry is used to determine which galaxies host an active galactic nucleus (AGN). In properties including source counts, mass distributions, and IR vs. radio luminosity relation, the ASKAP detected radio sources behave as expected. Radio galaxies have higher stellar mass and luminosity in IR, optical and UV than other galaxies. We apply optical and IR AGN diagnostics and find that they disagree for $\sim$30% of the galaxies in our sample. We suggest possible causes for the disagreement. Some cases can be explained by optical extinction of the AGN, but for more than half of the cases we do not find a clear explanation. Radio sources are more likely ($\sim$6%) to have an AGN than radio quiet galaxies ($\sim$1%), but the majority of AGN are not detected in radio at this sensitivity., Comment: 26 pages, 22 figures, 6 tables. Accepted for publication in Publications of the Astronomical Society of Australia

The present Time Differential Perturbed γ-γ Angular Correlation (TDPAC) measurements in bulk HfO2 report, for the first time, the presence of three regular sites at ambient condition, apart from the stable monoclinic phase (m-HfO2). Also, the effects of Gd impurity (5 at%) on HfO2 crystal structure was investigated by PAC. In pure HfO2, apart from the monoclinic component (~76%), four other minor frequency components have been found at room temperature. To further investigate the origin of these minor frequency components, PAC measurement at 673 K was performed. At 673 K, population of two of the four minor components was enhanced at the expense of the m-HfO2 as the population of m-HfO2 reduces to ~58%. On doping with 5 at% Gd, the population of monoclinic site drastically reduced to ~10% while one of the minor components got enhanced to a large extent (68%). The enhancements of the three minor components, both by temperature or by Gd impurity, indicate that these are the regular phases of HfO2 and could therefore be attributed to three orthorhombic phases of HfO2. The fourth minor component (5–10%) with values of ωQ ~ 7 Mrad/s, η = 0 can be assigned to crystalline defect site.

The Time Differential Perturbed γ-γ Angular Correlation (TDPAC) measurement has been carried out with the hydrolysis product of Hafnium(Hf)-IV ion at pH1 both in bulk and under nano confinement using 181Hf/Ta as PAC probe. The experiment was performed at two different temperatures, viz., 300 K and 280 K. Three different probe sites could be identified for the bulk complex while it is four in case the complex is inside the nanopore, at both the measuring temperatures. The major site, in case of bulk complex, has a quadrupole frequency ωQ ~ 105 Mrad/s and η ~ 0.6. However, the major site, in case the complex is inside nanopore having an average pore size of 6 nm, has ωQ ~ 210 Mrad/s and η ~ 0.3. Two different values of PAC parameters corresponding to the major probe sites for the bulk and nano-confined complex, indicate completely different hydration chemistry in the present two cases.

We report the development and application of a method for carrying out computational investigations of the effects of mass and force-constant (FC) disorder on phonon spectra. The method is based on the recently developed typical medium dynamical cluster approach, which is a Green's function approach. Excellent quantitative agreement with previous exact diagonalization results establishes the veracity of the method. Application of the method to a model system of binary mass and an FC-disordered system leads to several findings. A narrow resonance, significantly below the van Hove singularity, that has been termed the boson peak, is seen to emerge for low soft particle concentrations. We show, using the typical phonon spectrum, that the states constituting the boson peak cross over from being completely localized to being extended as a function of increasing soft particle concentration. In general, an interplay of mass and FC disorder is found to be cooperative in nature, enhancing phonon localization over all frequencies. However, for a certain range of frequencies, and depending on material parameters, FC disorder can delocalize the states that were localized by mass disorder, and vice versa. Modeling vacancies as weakly bonded sites with vanishing mass, we find that vacancies, even at very low concentrations, are extremely effective in localizing phonons. Thus, inducing vacancies is proposed as a promising route for efficient thermoelectrics. Finally, we use model parameters corresponding to the alloy system, ${\mathrm{Ni}}_{1\ensuremath{-}x}{\mathrm{Pt}}_{x}$, and we show that mass disorder alone is insufficient to explain the pseudogap in the phonon spectrum; the concomitant presence of FC disorder is necessary.

Introduction: Breast cancer is the commonest malignancy in women worldwide. There are considerable variations in risk factors and presentation of the disease region wise. The present study aimed to describe clinical and pathological profile of breast cancer patients attending tertiary care hospital. Method: All consenting patients attending to surgical out-patient department (OPD) with complaints pertaining to breast disease were enrolled from 16th June 2015 to 15th June 2016. The patients were followed and demographic, clinical and pathologic information was recorded and analysed. Results: Total Of 180 patients with breast disease were enrolled. 34/100 were diagnosed of malignancy and formed the cases of the present study. Age of the patients ranged from 22 to 60 years with mean age of 42.06 ± 10.7 years. All the patients presented as breast lump variably associated with pain or discharge. Infiltrating Ductal Carcinoma Not Otherwise Specified (IDC NOS) was common histologic diagnosis (76.47%). Conclusion: Breast carcinoma presents with painless lump and patients are usually diagnosed in our setup at locally advanced stage. Implementation of the simple and effective screening programs for early detection is urgent need in our population.

In recent years, bio-inspired synthesis processes have drawn increasing research interest as a new tool for designing next generation advanced functional materials with unparalleled advantages. Bio-inspired process offers unique microstructures which are difficult to engineer through conventional synthesis methodologies. The present study aims to develop a bio-templating process of synthesizing BaBi0.2Co0.35Fe0.45O3−δ (BBCF) perovskite type oxygen separation membrane mimicking the interior of water hyacinth's (Eichhornia crassipes) petioles. In Indian sub-continent water hyacinth is considered as one of the worst aquatic weed whose removal is necessary from natural water reservoir to save aquatic environment. The idea of using such water pollutant to produce engineered microstructure for improving material's functionality is the philosophy behind the present study. The exo-templating of water hyacinth results in interesting microstructure and enhanced the physical properties of BBCF membrane in terms of oxygen permeation flux. The novel, simple method may be extended to produce any multifunctional advanced material with a spectacular microstructure and unique properties.

The present study aims to develop a series of novel perovskite based materials with a nominal composition of LaxSr1-xBi0.2Co0.35Fe0.45O3-δ (x = 0.5 to 0.8) as oxygen separation membranes. The powder has been synthesized by a soft chemical alanine assisted combustion method. X-ray diffractograms of calcined powders reveal orthorhombic perovskite structure. The optical properties measured by UV-VIS spectroscopy suggest that the variation of lanthanum concentration has mere effect in the electron density as well as band gap of the membranes. Total electrical conductivity as calculated is maximum for the composition with lowest lanthanum concentration (La = 0.5). The permeation flux as measured reveals that the flux generally decreases as the lanthanum concentration increases in the stoichiometry. A highest oxygen permeation flux of 0.23 ml/min/cm2 has been achieved for the composition La0.5Sr0.5Bi0.2Co0.35Fe0.45O3-δ at 900 °C.

The main theme of the work is to detect the traffic sign boards and alert the driver accordingly, which helps in reducing the violation of the traffic rules and also reduces the accidents that occur in day-to-day life. The vehicle will be able to guide the driver by providing the details of speed limit, traffic sign boards in high pedestrian density areas and the driver can change the speed within which the vehicle needs to operate and drive safely. The components that are used in the system design are raspberry pi 3 (module-b), ultrasonic sensor and web camera. The images of the traffic sign boards are captured using a web camera and the speed limit of the vehicle can be changed accordingly by the driver and will not be allowed to exceed the speed limit. In addition this system may help in analyzing the driving pattern.

The present work reports the microscopic details of anatase (A) to rutile (R) phase transformation in a Mn-doped TiO2 system. Titanium dioxide (TiO2) powder was synthesized at three different dopant percentages, namely 1, 5, and 10 atom% of Mn, by a coprecipitation technique. Time differential perturbed angular correlation (TDPAC) spectroscopy was used to identify the formation of the rutile-like phase (R*) during the phase-transition process and revealed interface nucleation to be promoted by the Mn dopant. Electron paramagnetic resonance (EPR) spectroscopy, synchrotron-based X-ray absorption near edge structure (XANES), and extended X-ray absorption fine structure (EXAFS) studies showed that Mn exhibited a mixed valence states of 2+ and 4+ at different stages of the annealing process. The rutile onset temperature gradually decreased with the increase in the Mn content. The present report proposes the mechanism for the phase transformation and details the effect of Mn on the A to R phase-transformation process. This can assist in gaining a fundamental understanding of the A to R phase-transformation process and the role of the dopant in stabilizing one phase over the other.

This study aims to investigate the effect of an engineered microstructure on the oxygen permeation property of a BaBi0.2Co0.35Fe0.45O3−δ (BBCF) type perovskite membrane. The interconnected multi-level cross-linked structure of the BBCF membrane has been synthesized by mimicking a common laboratory grade filter paper. The controlled calcination of the cellulose matrix results in a single phase BBCF structure when calcined at 950 °C in air. The average diameter of the interconnected BBCF fiber is about 1 μm as confirmed by FESEM. The electrical conductivity is measured to be ∼20 S cm−1 at 800 °C, higher than that of other conventionally prepared BBCF based membranes. The perovskite membrane derived by exo-templating of the filter paper's cellulose fiber reveals an enhanced oxygen permeation flux of 0.98 ml min−1 cm−2 at 900 °C.

Zirconia stabilized with 11 mol% scandia (11ScSZ) has been successfully synthesized by novel alanine-assisted soft chemical aqueous combustion method. The reaction kinetics during combustion synthesis has been studied in detail by analysing thermal behaviour of different metal–alanine complexes. A single phase 11ScSZ powder is achieved at significantly low calcination temperature of 500∘C. Field emission scanning electron micrograph reveals an agglomerated morphology with particle size ranging from 80 to 100 nm. The thermal expansion coefficient is found to be 11.03 × 10−6 ∘C−1 in the temperature range between room temperature and 1000∘C. Optical bandgap of 5.19 eV has been determined using UV–Vis spectroscopy and results are compared with the help of theoretical density of states. The total electrical conductivity of sintered pellet is found to be 7.3 × 10−3 S cm−1 at 700∘C as measured by impedance spectroscopy.

The effect of disorder on lattice vibrational modes has been a topic of interest for several decades. In this work, we employ a Green's function based approach, namely the dynamical cluster approximation (DCA), to investigate phonons in mass disordered systems. Detailed benchmarks with previous exact calculations are used to validate the method in a wide parameter space. An extension of the method, namely the typical medium DCA (TMDCA), is used to study Anderson localization of phonons in three dimensions. We show that, for binary isotopic disorder, lighter impurities induce localized modes beyond the bandwidth of the host system, while heavier impurities lead to a partial localization of the low-frequency acoustic modes. For a uniform (box) distribution of masses, the physical spectrum is shown to develop long tails comprising mostly localized modes. The mobility edge separating extended and localized modes, obtained through the TMDCA, agrees well with results from the transfer matrix method. A re-entrance behavior of the mobility edge with increasing disorder is found that is similar to, but somewhat more pronounced than, the behavior in disordered electronic systems. Our work establishes a new computational approach, which recovers the thermodynamic limit, is versatile and computationally inexpensive, to investigate lattice vibrations in disordered lattice systems., Comment: 14 pages, 10 figures

Background: Medicinal plants occupy an important position for being the paramount sources of drug discovery against cancer. Medicinal plants have been used as cancer chemopreventive nutraceuticals, and functional food is promising. Thus, there is a need for exploring drugs/agents which act as best chemopreventive agents. Lawsonia inermis L. is a well-known medicinal plant which has been used in Ayurvedic medicine as hepatoprotective, antiviral, antibacterial, anti-inflammatory, antipyretic, and cytotoxic. Objectives: The main objective of the study is to investigate the in vivo antitumoral effect of L. inermis extract on melanoma tumor-bearing C57BL/6 mice. Materials and Methods: In in vivo experiments, about 5 × 105 B16F10 cells in 50 μL of phosphate-buffered saline were subcutaneously injected into C57BL/6 mice that had received plain drinking water for 40 days. Tumor volume was measured using digital calipers. The behavior of the antioxidant defenses (superoxide dismutase, catalase, and glutathione peroxidase) was evaluated after the termination of treatments. Results: Preventive oral administration of L. inermis leave extracts (500 and 1000 mg/kg body weight) significantly suppressed the growth of B16F10 tumors in mice on day 40th, with an increased tumor necrosis area, increased infiltration of mononuclear cells at the site of the tumor. L. inermis L. leaf extract dose dependently reduced the amounts of free oxygen radicals (hydroxyl and superoxide anion radicals), generated in chemical systems. Conclusion: Our study suggests that in vivo antitumoral effect of L. inermis extracts is directly linked with enhanced antioxidant activity and depicted a significant reduction in tumor size against melanoma tumor. Hence, further elucidation of active components of L. inermis extract could lead to the development of potent antitumor agent or complementary and alternative medicine for the treatment against skin melanoma tumors.

BaBi 0.2 Co 0.35 Fe 0.45 O 3− δ (BBCF) single phase perovskite has been successfully synthesized by a novel alanine assisted soft chemical combustion method. Thermal behavior of metal alanine complexes during combustion to form BBCF perovskite structure has been studied in detail. X-ray diffraction patterns reveal that the formation of single phase BBCF perovskite proceeds by formation of several intermediate phases. A single phase BBCF powder is obtained at a temperature of 950 °C. Homogeneous distribution of multiple dopants in BBCF matrix is confirmed by elemental mapping using FESEM. The electrical conductivity reveals that with the increase in sintering temperature, conductivity of BBCF increases, reaches to a maximum value of 10.38 S cm −1 at 800 °C when measured in air for samples sintered at 950 °C and upon further increase in sintering temperature, the conductivity decreases gradually. Up to 800 °C, BBCF shows a semiconducting behavior and subsequently follows metallic conduction above 800 °C while performing electrical conductivity measurement in air.

LiMn 2 O 4 and LiNi 0.5 Mn 1.5 O 4 powders have been synthesized by a novel cost-effective carbon exo-templating process. It has been observed that controlled nucleation in the pores of highly surface active carbon produces a distinct effect on the powder morphology and crystallinity. Quantitative X-ray phase analyses show single phase spinel structure having Fd3m symmetry for both samples. Field emission electron microscopy reveals particles of size 0.5–1.0 µm with well defined multi-faceted crystals. Cyclic voltammetry results show well separated distinct redox peaks at 4.05/3.92 and 4.17/4.08 V for LiMn 2 O 4 /Li and 4.91/4.61 V for LiNi 0.5 Mn 1.5 O 4 /Li coin cells indicating good crystallinity and reversibility of the cathodes compared to that of pristine LiMn 2 O 4 synthesized by conventional combustion process. The LiMn 2 O 4 /Li and LiNi 0.5 Mn 1.5 O 4 /Li cells deliver an initial discharge capacity of 110 mA h/g and 122 mA h/g respectively at a current density of 0.05 mA/cm 2 and when cycled at 0.2 mA/cm 2 , the cells maintain 81% and 96% of their initial discharge capacity respectively even after 20 cycles. On the other hand, at the same current density, LiMn 2 O 4 synthesized by conventional combustion process suffers from severe capacity fading (only 37.5% capacity retention after the 25th cycle). The capacity fading rate is found to be very less even at further higher current densities (0.4–0.8 mA/cm 2 ) for both LiMn 2 O 4 /Li and LiNi 0.5 Mn 1.5 O 4 /Li cells synthesized by the templating process. The present study reveals that high crystallinity along with multi-faceted morphology shows a remarkable enhancement in capacity as well as rate performance of pristine LiMn 2 O 4 and its Ni derivative.

Ni-doped lithium manganese oxysulfides with a nominal composition of LiNi x Mn 2− x O 4− δ S δ (0 ≤ x ≤ 0.5 and 0 ≤ δ ≤ 0.1) have been synthesized by an alanine-assisted, low-temperature combustion process, followed by calcination at 700 °C in air. Quantitative X-ray phase analyses show that the spinel structure of LiMn 2 O 4 is retained for all compositions. However, analysis of the vibrational peaks observed in Fourier transformed infrared (FTIR) spectroscopy suggests that the Fd3m crystal symmetry is retained only up to x ≤ 0.4 and changes to P4 3 32 symmetry for x = 0.5. A systematic change in microstructure is observed with increasing Ni content in presence of S. The shape of the particles changes from spherical (LiMn 2 O 4 ) to icosahedron (LiNi 0.2 Mn 1.8 O 4− δ S δ ) to octahedron (LiNi 0.5 Mn 1.5 O 4− δ S δ ). UV–vis spectroscopy shows that the band structure of pristine LiMn 2 O 4 is strongly influenced by hybridization among Mn 3d and O 2p orbitals near the Fermi level and the band gap (1.45 eV) gradually decreases with increasing nickel content and reaches the minimum (1.35 eV) for LiNi 0.4 Mn 1.6 O 4 −δ S δ . Electrochemical results on 2032 coin-type cells, fabricated with the synthesized powders as the positive electrode (cathode) and Li metal as the negative electrode (anode), reveal that the substitution of S for O and Ni for Mn in LiMn 2 O 4 enhances the structural integrity of the spinel host, which in turn increases the electrochemical cycleability. A high initial discharge capacity of 155 mAh g −1 is obtained for a LiNi 0.4 Mn 1.6 O 4− δ S δ /Li cell with about 87% capacity retention (135 mAh g −1 ) after 25 cycles at a current density of 0.2 mA cm −2 . All LiNi x Mn 2− x O 4− δ S δ /Li cells ( x = 0.2–0.5) show excellent reversibility with nominal capacity fading (0.04–0.2 mAh per cycle) at a current density of 0.2 mA cm −2 .

Lithium titanate (Li 4 Ti 5 O 12 ) powder has been synthesized by a novel aqueous combustion process using a common amino acid alanine, as fuel. Thermogravimetric analysis of the gel indicates sharp single step combustion at ∼200 °C where nearly 80% weight loss occurs. X-ray analysis shows that the as-synthesized powder contains mostly spinel Li 4 Ti 5 O 12 phase along with anatase TiO 2 . About 90% phase purity is obtained when calcined at 800 °C in air. Observation under a Field Emission Scanning Electron Microscope reveals spherical shaped particles with uniform morphology. The particle size as estimated from the micrograph is in the range 40–80 nm. Fourier transformed infrared spectroscopy shows the characteristics bands of Li 4 Ti 5 O 12 at 652 and 462 cm −1 even in the as-synthesized powder. A wide optical band gap of 1.80 eV has been determined from UV–vis spectroscopy.

Nanocrystalline LiMn 2 O 4 powders have been synthesized by combustion process in a single step using a novel fuel, l -alanine. Thermogravimetric analysis and differential thermal analysis of the gel indicate a sharp combustion at a temperature as low as 149 °C. Quantitative phase analysis of X-ray diffraction data shows about 97% of phase purity in the as-synthesized powder, which on further calcination at 700 °C becomes single phase LiMn 2 O 4 . High Brunauer, Emmett, and Teller surface area values obtained for ash (53 m 2 /g) and calcined powder (23 m 2 /g) indicate the ultrafine nature of the powder. Average crystallite size is found to be ∼60–70 nm from X-ray diffraction analysis and transmission electron microscopy. Fourier transformed infra-red spectrum shows two strong bands at 615 and 511 cm −1 originating from asymmetrical stretching of MnO 6 octahedra. A nominal composition of Li 0.88 Mn 2 O 4 is calculated from the inductive coupled plasma analysis. From UV–vis spectroscopy, an optical band gap of 1.43 eV is estimated which is assigned to a transition between t 2g and e g bands of Mn 3d. Electrochemical charge–discharge profiles show typical LiMn 2 O 4 behavior with a specific capacity of 76 mAh/g.

Nanocrystalline SOFC cathode materials of perovskite family, La(1-x)Sr(x)M(1-y)Co(y)O(3), where 0

Nanocrystalline LiCoO2 powders (10–50 nm) were synthesized by a citrate-nitrate combustion process followed by calcination at different temperatures (300–800 °C) in air. Thermogravimetric analyses indicated a sharp combustion at a low temperature of 225 °C, producing fine crystallites. Quantitative phase analyses from the x-ray diffractograms showed that while annealing at 500 °C produced mixed phases of cubic and rhombohedral LiCoO2, annealing at 800 °C resulted in single-phase rhombohedral LiCoO2. Electronic transitions related to the Co 3d bands were investigated by ultraviolet-visible reflectance spectra in absorbance mode and were ascribed to the Co 3d intra-band transition involving t2g and eg orbitals. The d-d transitions underwent a blue shift of about 0.3 eV as the cubic LiCoO2 transformed into the rhombohedral structure with band gap values of about 1.4 and 1.7 eV.

This paper presents a front end Luo DC-DC Converter with Snubber circuit to provide high voltage gain, less voltage Ripple, less switching losses, can lead to high Converter Efficiency over the entire input voltage and load variation. The basic idea of the proposed Luo DC-DC Converter is using the positive voltage lifting technique to increase voltage gain, Snubber circuit provide a ZCT-ZVT based Soft Switching in order to reduce the switching losses, and proportional-Integral to improve the static and dynamic performance in order to further increase the Efficiency of such type of Converter. For analyzing and investigating of Converter is done by proper simulation with measurement at each terminal.

Hepatitis B virus (HBV) infection in cancer patients receiving chemotherapy carries high morbidity and mortality. Conventional hepatitis B vaccination with three doses at 0, 1, and 6 months apart is ineffective in prevention of HBV infection. To compare the efficacy of accelerated, multiple, double-dose HB vaccine with conventional HB vaccine in cancer patients receiving chemotherapy (CT). Patients of cancer who were planned for CT were screened for HBV markers (HBsAg, total anti-HB core, anti-HBs antibody and HBV DNA). Patients with negative HBV serum markers received HB vaccine in two groups. Group A received three double doses (40 μg) of recombinant HB vaccine at 0, 1, and 3 weeks before CT and additional three double doses post CT. Group B received HB vaccine (20 μg) at 0, 1, and 6 months. Efficacy of vaccine in the two groups was compared by anti-HBs titers achieved at 3, 6, and 9 months and by HBsAg positivity following CT at 1 year follow up. Protective anti-HBs titers (>10 mIU/mL) at 3, 6, and 9 months in group A and B was 41.1 %, 66.2 %, and 76 % and 26 %, 37.7 %, and 49 % respectively (p = 0.001). Seven of 454 (1.5 %) patients in group A became HBsAg positive after vaccination compared to 19/472 (4.0 %) in group B (p = 0.022). Accelerated, multiple, double-dose HB vaccine increases seroprotection and is more effective than conventional HB vaccine in preventing HBV infection.