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We report the effect of La0.7Sr0.3MnO3 (LSMO) electrodes on the temperature dependence of the magnetoresistance (MR) of LSMO/polymer/cobalt spin valves (SVs). LSMO films have been prepared by pulsed laser deposition on three different single crystal substrates using different deposition parameters. The films were characterized for their surface morphologies, structural, magnetic, and magnetotransport properties. Low deposition rate is found to be detrimental for growth of good quality films and polycrystalline films with grain boundary effects are observed in thicker films. The films on MGO (100) substrate show a broad paramagnetic to ferromagnetic transition, accompanied with a metal-insulator transition below room temperature. This indicates growth of some strained structures due to large lattice mismatch (9%) between the substrate and the film and presence of polycrystalline grain boundaries. The deposited films on STO (100) and NGO (001) show much sharper magnetic transition and metallic behavior indicating higher spin polarization (SP) of LSMO on these substrates at room temperature. SVs made on STO (100) show improvement in switching behavior and better MR response compared to the devices made on MGO (100) at low temperatures. No difference in MR response was found at room temperature in either case. We conclude that the bulk spin polarization of LSMO films is not very important in the SV operation. The loss of most of the SP carriers at the LSMO/organic semiconductor interface at room temperature is a more dominant effect and drastically reduces the MR signal. [ABSTRACT FROM AUTHOR]

Ability to digitally control the amount of a deposited material is one of the many advantages of inkjet printing. In this letter, we demonstrate the applicability of inkjet printing for the fabrication of depletion-load nMOS inverters based on metal oxide thin-film-transistors (TFTs) from printed metal oxide precursors where the threshold voltage of the TFTs is controlled by adjusting the thickness of the deposited semiconductor layer. Enhancement- and depletion-mode n-type In2O3 TFTs were fabricated from In-nitrate precursor using two printing strategies: 1) multilayer multinozzle printing and 2) single-layer single-nozzle printing in perpendicular or parallel to the TFT channel. TFTs with saturation mobility up to \sim 2.4 cm2/( \text {V}\cdot \text {s} ) and the ON/OFF-ratio of 10^{7}$ were obtained after annealing at 300 °C. Devices connected as depletion-load nMOS inverters showed gain up to $\sim 26$ on a Si/SiO2 substrate, and an inverter on a flexible polyimide substrate with atomic layer deposited Al2O3 dielectric was demonstrated with a maximum gain of $\sim 45$ . [ABSTRACT FROM AUTHOR]

Elastic scattering angular distributions for 6Li+Si system were measured at and analyzed along with the existing data from the previous measurements in the energy range of . The measured cross-sections and the existing data, forming a set of angular distributions over a range of E/, were analyzed using the phenomenological optical model potential (OMP). Three different sets of potential parameters were used. The energy dependence of the real and the imaginary potential strengths were, subsequently, extracted at the radius of sensitivity () for the system. Continuum Discretized Coupled Channel (CDCC) calculation was performed to explore the contribution of projectile break-up (BU) on the observed energy dependence of the effective potential for elastic scattering of 6Li from Si. The energy variation of the strength of the real potential with continuum coupling was found to agree with the energy dependence of the same extracted from the (OMP) analysis at energies around the barrier. But the behavior of the imaginary strength appeared to be different. The calculated fusion cross-sections, including the effect of BU, clearly overestimated the measured fusion excitation function data in the below and near barrier energies but compared well with the data at higher energies. [ABSTRACT FROM AUTHOR]

We propose a combined far ultraviolet (FUV) and thermal annealing method of metal-nitrate-based precursor solutions that allows efficient conversion of the precursor to metal-oxide semiconductor (indium zinc oxide, IZO, and indium oxide, In2O3) both at low-temperature and in short processing time. The combined annealing method enables a reduction of more than 100 °C in annealing temperature when compared to thermally annealed reference thin-film transistor (TFT) devices of similar performance. Amorphous IZO films annealed at 250 °C with FUV for 5 min yield enhancement-mode TFTs with saturation mobility of ~1 cm2/(V·s). Amorphous In2O3 films annealed for 15 min with FUV at temperatures of 180 °C and 200 °C yield TFTs with low-hysteresis and saturation mobility of 3.2 cm2/(V·s) and 7.5 cm2/(V·s), respectively. The precursor condensation process is clarified with x-ray photoelectron spectroscopy measurements. Introducing the FUV irradiation at 160 nm expedites the condensation process via in situ hydroxyl radical generation that results in the rapid formation of a continuous metal-oxygen-metal structure in the film. The results of this paper are relevant in order to upscale printed electronics fabrication to production-scale roll-to-roll environments. [ABSTRACT FROM AUTHOR]

Fusion excitation functions are measured for the system 6Li + 28Si using the characteristic $ \gamma$ -ray method, encompassing both the sub-barrier and above-barrier regions, viz, Elab = 7-24 MeV. Two separate experiments were performed, one for the above-barrier region ( Elab = 11-24 MeV) and another for the below-barrier region ( Elab = 7-10 MeV). The results were compared with our previously measured fusion cross-section for the 7Li + 28Si system. We observed the enhancement of the fusion cross-section at sub-barrier regions for both 6Li and 7Li , but the yield was substantially larger for 6Li . However, for well-above-barrier regions, a similar type of suppression was identified for both the systems. [ABSTRACT FROM AUTHOR]

The relative stability of superheavy elements against beta-decay and spontaneous fission has been investigated. A simple criterion of beta-stability using the Fermi gas model has been developed, tested in the range of stable nuclei and extended to the superheavy region. Spontaneous fission half-lives have been calculated using the statistical model in the expected region of relative beta-stability for superheavy nuclei. Our results have been compared with previous calculations. [ABSTRACT FROM AUTHOR]

In order to study distributions of fecundability, Potter and Parker fitted a Pearson Type I geometric distribution (with parameters a and b) to data from the Princeton Fertility Study. They, and subsequently other authors, estimated a and b from the observed moments of the month of first conception. A critical analysis of this method has shown that moment estimators of a and b are moderately reliable only within a specified range of values of a. Outside this range, either the estimators are extremely inefficient or their variances are not defined at all. Caution should therefore be taken in adopting this procedure. Furthermore, no moment estimate is defined when a is less than 2. It seems preferable to derive maximum likelihood estimates which have certain optimal properties and are defined for all permissible (i.e. positive) values of a and b. For large samples, we here present: the covariance matrix (where defined) of the moment estimators, methods of obtaining maximum likelihood estimates and their covariance matrix, and the variances of estimates of specified moments of the fecundability of the sample. Results were obtained for three sets of data; in all cases, the maximum likelihood estimates fit the data better than do the moment estimates. Despite a substantial improvement, however, the fit is still poor for the two sets of data from the Princeton Fertility Study. Possible explanations are: a) that the departures from the assumption of constant fecundability for each couple are sufficient to produce the poor fit, b) that the data are inaccurate, or c) that the method of defining the sample of women from whom the data were obtained resulted in an over-representation of short conception times. The relative importance of these factors is difficult to establish. [ABSTRACT FROM AUTHOR]