830 research outputs found

    Chemical kinetics computer program for static and flow reactions

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    General chemical kinetics computer program for complex gas mixtures has been developed. Program can be used for any homogeneous reaction in either one dimensional flow or static system. It is flexible, accurate, and easy to use. It can be used for any chemical system for which species thermodynamic data and reaction rate constant data are known

    General chemical kinetics computer program for static and flow reactions, with application to combustion and shock-tube kinetics

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    A general chemical kinetics program is described for complex, homogeneous ideal-gas reactions in any chemical system. Its main features are flexibility and convenience in treating many different reaction conditions. The program solves numerically the differential equations describing complex reaction in either a static system or one-dimensional inviscid flow. Applications include ignition and combustion, shock wave reactions, and general reactions in a flowing or static system. An implicit numerical solution method is used which works efficiently for the extreme conditions of a very slow or a very fast reaction. The theory is described, and the computer program and users' manual are included

    GCKP84-general chemical kinetics code for gas-phase flow and batch processes including heat transfer effects

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    A general chemical kinetics code is described for complex, homogeneous ideal gas reactions in any chemical system. The main features of the GCKP84 code are flexibility, convenience, and speed of computation for many different reaction conditions. The code, which replaces the GCKP code published previously, solves numerically the differential equations for complex reaction in a batch system or one dimensional inviscid flow. It also solves numerically the nonlinear algebraic equations describing the well stirred reactor. A new state of the art numerical integration method is used for greatly increased speed in handling systems of stiff differential equations. The theory and the computer program, including details of input preparation and a guide to using the code are given

    LabVIEW Serial Driver Software for an Electronic Load

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    A LabVIEW-language computer program enables monitoring and control of a Transistor Devices, Inc., Dynaload WCL232 (or equivalent) electronic load via an RS-232 serial communication link between the electronic load and a remote personal computer. (The electronic load can operate at constant voltage, current, power consumption, or resistance.) The program generates a graphical user interface (GUI) at the computer that looks and acts like the front panel of the electronic load. Once the electronic load has been placed in remote-control mode, this program first queries the electronic load for the present values of all its operational and limit settings, and then drops into a cycle in which it reports the instantaneous voltage, current, and power values in displays that resemble those on the electronic load while monitoring the GUI images of pushbuttons for control actions by the user. By means of the pushbutton images and associated prompts, the user can perform such operations as changing limit values, the operating mode, or the set point. The benefit of this software is that it relieves the user of the need to learn one method for operating the electronic load locally and another method for operating it remotely via a personal computer

    Understanding the nature of electronic effective mass in double-doped SrTiO3_{3}

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    We present an approach to tune the effective mass in an oxide semiconductor by a double doping mechanism. We demonstrate this in a model oxide system Sr1x_{1-x}Lax_xTiO3δ_{3-\delta}, where we can tune the effective mass ranging from 6--20me\mathrm{m_e} as a function of filling or carrier concentration and the scattering mechanism, which are dependent on the chosen lanthanum and oxygen vacancy concentrations. The effective mass values were calculated from the Boltzmann transport equation using the measured transport properties of thin films of Sr1x_{1-x}Lax_xTiO3δ_{3-\delta}. Our method, which shows that the effective mass decreases with carrier concentration, provides a means for understanding the nature of transport processes in oxides, which typically have large effective mass and low electron mobility, contrary to the tradional high mobility semiconductors.Comment: 5 pages with 4 figure

    Formulating foster care in Scotland for young children's emotional and mental wellbeing (short report)

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    Foster carers can play a key role in supporting a child’s recovery from abuse and neglect and improving their mental health, but optimising this requires appropriate formulation of the care arrangements. This is a report on a scoping study into the extent to which the way foster care as conceived and supported, provides the basis for meeting the emotional and mental health needs of young children. It focuses on children aged up to 60 months who have been removed from their parents’ care because of maltreatment, or risk of maltreatment and who have been placed in state provided (non-familial) foster care provision in Scotland. The project had three main objectives: 1. To establish what is known about the emotional and mental health needs of young children (aged zero to five years) coming into the care system. 2. To look at the preparation and support for foster carers in Scotland relevant to caring for these children, through analysis of local authority documents. 3. To explore the experience of foster carers in meeting the emotional and mental health needs of children, through interviews with a sample of foster carers

    Ion energy distribution measurements in rf and pulsed dc plasma discharges

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    A commercial retarding field analyzer is used to measure the time-averaged ion energy distributions of impacting ions at the powered electrode in a 13.56 MHz driven, capacitively coupled, parallel plate discharge operated at low pressure. The study is carried out in argon discharges at 10 mTorr where the sheaths are assumed to be collisionless. The analyzer is mounted flush with the powered electrode surface where the impacting ion and electron energy distributions are measured for a range of discharge powers. A circuit model of the discharge, in combination with analytical solutions for the ion energy distribution in radio-frequency sheaths, is used to calculate other important plasma parameters from the measured energy distributions. Radio-frequency compensated Langmuir probe measurements provide a comparison with the retarding field analyzer data. The time-resolved capability of the retarding field analyzer is also demonstrated in a separate pulsed dc magnetron reactor. The analyzer is mounted on the floating substrate holder and ion energy distributions of the impinging ions on a growing film, with 100 ns time resolution, are measured through a pulse period of applied magnetron power, which are crucial for the control of the microstructure and properties of the deposited films

    Enhanced effective mass in doped SrTiO3 and related perovskites

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    The effective mass is one of the main factors determining the Seebeck coefficient and electronic conductivity. Nb-doping increases the effective mass because of two reasons, lattice constants increase and electronic effects. In this ab-initio study the effective mass is estimated from the curvature of electronic bands and it could be clarified that the deformation of SrTiO3 crystals has a significant influence on bandgap and effective DOS and band mass, which are both in excellent agreement to experimental data. However, the electronic effect due to the e2g- band flattening near the Gamma-point due to Nb-doping up to 0.2 at% is the main factor for the increase of effective mass. Doping of La shows a linear decrease of the effective mass; this is explained by the different surrounding of A- and B-site. Substitution of other elements like Ba on the A-site and V on the B-site in SrTiO3 were also found to increase the effective mass.Comment: 10 pages, 11 figures, 3 table

    Sleeping to Remember: Spontaneous Retrieval of Prospective Memories Across Sleep and Wake Delays

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    Laboratory-based prospective memory tasks have rarely examined the effect of retention interval on later remembering. In the current study, participants had to remember to perform an intended action: press Q in response to a target cue) after a short delay: approximately 20 min), a 12-hr sleep delay, or a 12-hr wake delay. The results demonstrated a large decline in prospective memory performance after a 12-hr wake delay: relative to the short delay condition). Interestingly, prospective remembering was not only better following a 12-hr sleep delay than a 12-hr wake delay but performance in this condition did not differ significantly from performance in the short delay condition. Cost analyses: i.e., ongoing task performance decline associated with embedding a prospective memory task) demonstrated that spontaneous retrieval processes primarily supported prospective remembering. These results are discussed in relation to theories of prospective memory retrieval and sleep-dependent memory consolidation
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