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The macro-benthic crustacean diversity in the estuarine zones of Sundarban, West Bengal, India was studied for a period of six months (November, 2014 to April, 2015) in 21 sampling stations covering eastern, central and western zones of Sundarban. A total 20 species of crustaceans belonging to 3 orders, 9 families and 13 genera were recorded. The family Sesarmidae was dominated in number of taxa. The species recorded were Uca acuta, Uca rosea, Uca lactea, Uca triangularis, Uca dussumieri, Thalassina anomala, Dotilla intermedia, Dotilla blanfordi, Dotillopsis brevitarsis, Sesarma chiromantes, Sesarmops impressum, Perisesarma bidens, Episesarma mederi, Sesarmoides longipes, Parasesarma plicatum, Metaplax intermedia, Clibanarius padavensis, Scylla serrata, Balanus sp. and Squilla sp. Out of 20 species Balanus sp. was most abundant species followed by Uca acuta, Thalassina anomala and Uca rosea and the least abundant species were Dotilla intermedia, Sesarma chiromantes and Squilla sp. Species like Uca acuta, Dotilla intermedia, Sesarma chiromantes, Sesarmops impressum and Squilla sp. were found only in eastern zone. Major habitat of the species recorded was muddy substratum of littoral zone (42%). Other habitats include sandy substratum of littoral zone (5%), both muddy and sandy substrata of littoral zone (32%), hard substratum and populated by mangrove palm (5%), dead trees and stumps (5%) and mud flat (11%). [ABSTRACT FROM AUTHOR]

The design of a microstrip patch antenna in the S band for nano-satellite application is presented. Two self biased ferrite disks are inserted in the resonant region of the patch to obtain circular polarization. The addition of ferrite disks results in gain enhancement, increase in bandwidth and decrease in axial ratio. Experimental results show that the antenna has a gain of 6.159 dB, an impedance bandwidth of 140 MHz at a resonant frequency of 2.455 GHz and an axial ratio of 1.016 which is in concurrence with the simulated results. [ABSTRACT FROM AUTHOR]

Lead free scandium doped barium zirconate titanate (BaSc)(ZrTi)O abbreviated as (BScZT) (x = 0.02, 0.04, 0.06, 0.08, 0.10) ceramics were prepared by the conventional solid state reaction route and their structural, microstructural and electrical properties were investigated experimentally. X-ray diffraction and Rietveld refinement analysis are indexed by considering cubic symmetry having space group Pm-3 m. Scandium ion (Sc) substitution induced A-site vacancies and distortion in three dimensional cation-oxygen networks leads to disorder in the local symmetry as identified in Raman spectra. The microstructural image shows formation of smaller grains of irregular shape and sizes along with aggregative characteristic with successive increase in Sc concentration. Lorentz type quadratic behavior in dielectric dispersion follows modified Curie-Weiss law and indicates a relaxor behavior with diffuse type of phase transition. A non-Debye type of relaxation behavior is observed in these materials. Variation of relaxation strength and diffuse parameters obey the Vogel-Fulcher relation. The ac conductivity highlights the hopping of bound charge carriers between the localized environment at lower temperature and translation hopping at higher temperature is modeled through universal dielectric response. [ABSTRACT FROM AUTHOR]

Control of the spin degree of freedom of an electron has brought about a new era in spin-based applications, particularly spin-based electronics, with the potential to outperform the traditional charge-based semiconductor technology for data storage and information processing. However, the realization of functional spin-based devices for information processing remains elusive due to several fundamental challenges such as the low Curie temperature of group III-V and II-VI semiconductors (<200 K), and the low spin-injection efficiencies of existing III-V, II-VI, and transparent conductive oxide semiconductors in a multilayer device structure, which are caused by precipitation and migration of dopants from the host layer to the adjacent layers. Here, we use catalyst-assisted pulsed laser deposition to grow, for the first time, oxygen vacancy defect-rich, dopant-free ZrO2 nanostructures with high TC (700 K) and high magnetization (5.9 emu/g). The observed magnetization is significantly greater than both doped and defect-rich transparent conductive oxide nanomaterials reported to date. We also provide the first experimental evidence that it is the amounts and types of oxygen vacancy defects in, and not the phase of ZrO2 that control the ferromagnetic order in undoped ZrO2 nanostructures. To explain the origin of ferromagnetism in these ZrO2 nanostructures, we hypothesize a new defect-induced bound polaron model, which is generally applicable to other defect-rich, dopant-free transparent conductive oxide nanostructures. These results provide new insights into magnetic ordering in undoped dilute ferromagnetic semiconductor oxides and contribute to the design of exotic magnetic and novel multifunctional materials. [ABSTRACT FROM AUTHOR]

The vertical downward migration of U in soils collected from south-western Punjab was studied from the depth distributions using the diffusion-convection model. The time-dependent convective rates ( ν) of U were found to be in the order of 10-10 cm year, whereas under the assumption of steady state (time-independent), values were in the order of 10-10 cm year. However, the diffusion rates ( D) were in the order of 10-10 cm year and under the steady state, values obtained to be relatively higher as 0.002-0.70 cm year. These values were within the range of reported literature values. [ABSTRACT FROM AUTHOR]

ABSTRACT This article presents quad-directional magneto-dielectric (MD) resonator antenna configuration, designed using two different MD materials with stack configuration. These materials have been designed such that their temperature coefficient is approximately zero. The microwave dielectric constant (εr) and permeability (μr) of both materials are calculated by Nicholson-Ross-Weir conversion technique and found to be 8.02, 1.64 and 10.47, 1.52, respectively. The designed antenna can radiates in four directions simultaneously at the resonant frequency of 5.84 GHz. The beam shaping has been achieved using single feed and this property can be utilized for the angle diversity. © 2016 Wiley Periodicals, Inc. Microwave Opt Technol Lett 58:62-64, 2016 [ABSTRACT FROM AUTHOR]

Introduction: With up to 8.55 wt% carbon [1], ureilites are the most carbon-rich meteorites. Graphite is the most abundant carbon allotrope, typically located in interstitial sites between silicate grains. Main group ureilites have experienced varying degrees of shock processing, altering their texture [e.g., 2]. Understanding the carbon mineralogy is crucial for interpretations regarding the processing of the ureilite parent body (UPB) [e.g., 3, 4], the debated origin of diamonds [e.g., 5-7], and graphite-based geothermometry [e.g., 8]. Methods: Raman spectra were obtained in 14 samples with a IDR-Micro-532 micro-Raman spectrometer. A Nd:YAG laser with a wavelength of 532 nm, and a laser power of 1.1 mW on the sample surface was used. An analysis consisted of a measurement time of 10 s with 5 accumulations. The statistical evaluation included baseline subtraction, peak identification, and the extraction of selected parameters (e.g., G band position and FWHM). Results: Based on the texture, the investigated samples can be catergorized into coarse-grained and fine-grained ureilites. The G band positions of graphite in coarse-grained ureilites cluster in a confined range between 1580-1583 cm-1, corresponding to crystalline graphite. Shock indicators in olivine [cf. 9] suggest that these coarsegrained samples have experienced relatively low shock pressures up to 15-20 GPa. In contrast, the Raman signatures obtained in fine-grained ureilties show a large variability and significantly higher G band positions/FWHMs, which can be attributed to a high degree of crystallographic disorder. Overall, the G band position and the G band FWHM show a nearly linear positive correlation. Discussion: A strong correlation between the texture (coarse-grained and fine-grained) and the Raman signature of graphite (crystalline graphite and disordered graphite/poorly graphitized carbon) can be observed. This raises the question, which underlying process is responsible for the increased crystallographic disorder present in graphite in fine-grained ureilites? One key observation is that the carbon phases in fine-grained ureilites often occur in textural units, which resemble the shape of graphite grains found in coarse-grained ureilites. This suggests that graphite was highly crystalline in the first place, and was subsequently replaced/modified by parent body processing. The resulting carbon phases in fine-grained ureilites are considerably more diverse compared to coarse-grained ureilites, where graphite is by far the dominant carbon allotrope. Most likely, the underlying mechanism is related to the same process, which lead to mosaicism and the visible fragmentation of silicates. In this case, the process should be related to post-accretionary shock, induced by high velocity impacts. Yet, it is unclear whether disordered graphite is a direct product of the transformation from highly crystalline graphite, or if disordered graphite might also result from the back-transformation of diamond. Conclusion: The parent body processing of ureilties has a significant effect on the carbon mineralogy. The G band parameters of graphite in finegrained and coarse-grained ureilites form two clusters, which plot on a nearly linear trend reflecting crystallographic order. Presumably, the underlying process is related to the post-accretionary shock processing of the ureilite parent body. [ABSTRACT FROM AUTHOR]

Anthropogenic hyperalkaline sites provide an environment that is analogous to proposed cementitious geological disposal facilities (GDF) for radioactive waste. Under anoxic, alkaline conditions cellulosic wastes will hydrolyze to a range of cellulose degradation products (CDP) dominated by isosaccharinic acids (ISA). In order to investigate the potential for microbial activity in a cementitious GDF, cellulose samples were incubated in the alkaline (∼pH 12), anaerobic zone of a lime kiln waste site. Following retrieval, these samples had undergone partial alkaline hydrolysis and were colonized by a Clostridia-dominated biofilm community, where hydrogenotrophic, alkaliphilic methanogens were also present. When these samples were used to establish an alkaline CDP fed microcosm, the community shifted away from Clostridia, methanogens became undetectable and a flocculate community dominated by Alishewanella sp. established. These flocs were composed of bacteria embedded in polysaccharides and proteins stabilized by extracellular DNA. This community was able to degrade all forms of ISA with >60% of the carbon flow being channelled into extracellular polymeric substance (EPS) production. This study demonstrated that alkaliphilic microbial communities can degrade the CDP associated with some radioactive waste disposal concepts at pH 11. These communities divert significant amounts of degradable carbon to EPS formation, suggesting that EPS has a central role in the protection of these communities from hyperalkaline conditions. [ABSTRACT FROM AUTHOR]