Properties Study of ZnS Thin Films Prepared by Spray Pyrolysis Method

Zinc sulfide (ZnS) is important II-VI semiconductors material for the development of various modern technologies and photovoltaic applications. ZnS thin film was prepared by using chemical spray pyrolysis technique. The starting solution is a mixture of 0.1 M zinc chloride as source of Zn and 0.05 M thiourea as source of S. The glass substrate temperature was varied in the range of 300 °C-400 °C to investigate the influence of substrate temperature on the structure, chemical composition, morphological and optical properties of ZnS films. The DRX analyses indicated that ZnS films have polycrystalline cubic structure with (111) preferential orientation and grain size varied from 25 to 60 nm, increasing with substrate temperature. The optical properties of these films have been studied in the wavelength range 300-2500 nm using UV-VIS spectro-photometer. The ZnS films has a band gap of 3.89 eV-3.96 eV

Properties Study of ZnS Thin Films Prepared by Spray Pyrolysis Method

Zinc sulfide (ZnS) is important II-VI semiconductors material for the development of various modern technologies and photovoltaic applications. ZnS thin film was prepared by using chemical spray pyrolysis technique. The starting solution is a mixture of 0.1 M zinc chloride as source of Zn and 0.05 M thiourea as source of S. The glass substrate temperature was varied in the range of 300 °C-400 °C to investigate the influence of substrate temperature on the structure, chemical composition, morphological and optical properties of ZnS films. The DRX analyses indicated that ZnS films have polycrystalline cubic structure with (111) preferential orientation and grain size varied from 25 to 60 nm, increasing with substrate temperature. The optical properties of these films have been studied in the wavelength range 300-2500 nm using UV-VIS spectro-photometer. The ZnS films has a band gap of 3.89 eV-3.96 eV

Characterization of Thermally Oxidized Ti6Al4V Alloys for Dental Application

In this work, thermal oxidation processes in the temperature range of 500-800 °C in air for 4 hours were performed on Ti6Al4V medical grade alloys to modify their surface structure and morphology for better wear and corrosion resistance, osseointegration and biocompatibility. Different type and amount of nanostructured phases were obtained as revealed by the X-ray diffration (XRD) technique such as: alumina, anatase and rutile. X’pert high score plus software was used for the calculation of the percentage and crystallite sizes of these phases. Alumina phase exhibits the greater amount of the oxide layers when Ti6Al4V alloys annealed at 500 °C, while rutile was found to be the predominant phase at 800 °C

Acute Cauda Equina Syndrome after Percutaneous Transforaminal Endoscopic Discectomy

Percutaneous Endoscopic Lumbar discectomy (PELD) has proved to be a good alternative to open micro-discectomy for treatment of lumbar disc herniation. This technique has been shown to be associated with several peri-operative complications and morbidities. These include postoperative dysesthesia secondary to nerve root injury, dural tears, hematoma, infection and recurrence of disc herniation. In this report, we are presenting a rare case of L4-5 disc herniation that was treated surgically with PELD and was complicated by early recurrence causing acute cauda equina syndrome. Our aim is to highlight on this rare complication that should be taken into consideration by minimally invasive spine surgeons utilizing PELD in their practice

A self-consistent phase-space distribution function for the anisotropic dark matter halo of the Milky Way

Dark Matter (DM) direct detection experiments usually assume the simplest possible ‘Standard Halo Model’ for the Milky Way (MW) halo in which the velocity distribution is Maxwellian. This model assumes that the MW halo is an isotropic, isothermal sphere, hypotheses that are unlikely to be valid in reality. An alternative approach is to derive a self-consistent solution for a particular mass model of the MW (i.e. obtained from its gravitational potential) using the Eddington formalism, which assumes isotropy. In this paper we extend this approach to incorporate an anisotropic phase-space distribution function. We perform Bayesian scans over the parameters defining the mass model of the MW and parameterising the phase-space density, implementing constraints from a wide range of astronomical observations. The scans allow us to estimate the precision reached in the reconstruction of the velocity distribution (for different DM halo profiles). As expected, allowing for an anisotropic velocity tensor increases the uncertainty in the reconstruction of f (v), but the distribution can still be determined with a precision of a factor of 4-5. The mean velocity distribution resembles the isotropic case, however the amplitude of the high-velocity tail is up to a factor of 2 larger. Our results agree with the phenomenological parametrization proposed in Mao et al. (2013) as a good fit to N-body simulations (with or without baryons), since their velocity distribution is contained in our 68% credible interval

Superconductivity and a Mott Transition in a Hubbard Model on an Anisotropic Triangular Lattice

A half-filled-band Hubbard model on an anisotropic triangular lattice (t in two bond directions and t' in the other) is studied using an optimization variational Monte Carlo method, to consider the Mott transition and superconductivity arising in \kappa-BEDT-TTF_2X. Adopting wave functions with doublon-holon binding factors, we reveal that a first-order Mott (conductor-to-nonmagnetic insulator) transition takes place at U=U_c approximately of the band width, for a wide range of t'/t. This transition is not directly connected to magnetism. Robust d-wave superconductivity appears in a restricted parameter range: immediately below U_c and moderate strength of frustration (0.4\lsim t'/t\lsim 0.7), where short-range antiferromagnetic correlation sufficiently develops but does not come to a long-range order. The relevance to experiments is also discussed.Comment: 15 pages, 17 figures, submitted to J. Phys. Soc. Jp

Galactic Bulge Microlensing Optical Depth from EROS-2

We present a new EROS-2 measurement of the microlensing optical depth toward the Galactic Bulge. Light curves of $5.6\times 10^{6}$ clump-giant stars distributed over $66 \deg^2$ of the Bulge were monitored during seven Bulge seasons. 120 events were found with apparent amplifications greater than 1.6 and Einstein radius crossing times in the range 5 {\rm d}. This is the largest existing sample of clump-giant events and the first to include northern Galactic fields. In the Galactic latitude range 1.4\degr<|b|<7.0\degr, we find $\tau/10^{-6}=(1.62 \pm 0.23)\exp[-a(|b|-3 {\rm deg})]$ with $a=(0.43 \pm0.16)\deg^{-1}$. These results are in good agreement with our previous measurement, with recent measurements of the MACHO and OGLE-II groups, and with predictions of Bulge models.Comment: accepted A&A, minor revision

Evidence for structural and electronic instabilities at intermediate temperatures in κ\kappa-(BEDT-TTF)2_{2}X for X=Cu[N(CN)2_{2}]Cl, Cu[N(CN)2_{2}]Br and Cu(NCS)2_{2}: Implications for the phase diagram of these quasi-2D organic superconductors

We present high-resolution measurements of the coefficient of thermal expansion $\alpha (T)=\partial \ln l(T)/\partial T$ of the quasi-twodimensional (quasi-2D) salts $\kappa$-(BEDT-TTF)$_2$X with X = Cu(NCS)$_2$, Cu[N(CN)$_2$]Br and Cu[N(CN)$_2$]Cl. At intermediate temperatures (B), distinct anomalies reminiscent of second-order phase transitions have been found at $T^\ast = 38$ K and 45 K for the superconducting X = Cu(NCS)$_2$ and Cu[N(CN)$_2$]Br salts, respectively. Most interestingly, we find that the signs of the uniaxial pressure coefficients of $T^\ast$ are strictly anticorrelated with those of $T_c$. We propose that $T^\ast$ marks the transition to a spin-density-wave (SDW) state forming on minor, quasi-1D parts of the Fermi surface. Our results are compatible with two competing order parameters that form on disjunct portions of the Fermi surface. At elevated temperatures (C), all compounds show $\alpha (T)$ anomalies that can be identified with a kinetic, glass-like transition where, below a characteristic temperature $T_g$, disorder in the orientational degrees of freedom of the terminal ethylene groups becomes frozen in. We argue that the degree of disorder increases on going from the X = Cu(NCS)$_2$ to Cu[N(CN)$_2$]Br and the Cu[N(CN)$_2$]Cl salt. Our results provide a natural explanation for the unusual time- and cooling-rate dependencies of the ground-state properties in the hydrogenated and deuterated Cu[N(CN)$_2$]Br salts reported in the literature.Comment: 22 pages, 7 figure