11,650 research outputs found

    Using Pinterest in the Management Classroom

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    This paper discusses the potential value of using the social bookmarking site Pinterest in management courses. The general features and uses of Pinterest are described as well as how they can be applied in the management classroom. Pinterest offers a medium to facilitate student discovery and sharing of class relevant visual content. I discuss the use of Pinterest in my own training methods class with a class Pinterest board acting as a place for students to share class-relevant links to videos and online content based on assigned topics. I discuss other potential applications in management classes. I also discuss the logistics of implementation of a class Pinterest board and potential challenges of use

    Inflatable stretcher to transport patients

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    Inflatable plastic bag inside strong, inflexible outer bag facilitates emergency transport of seriously burned or disabled patients. When the bag is inflated the patient is completely immobilized and cushioned from external shock. Air for breathing, temperature controls and communications may be provided by appropriate plug-in connections

    Using Amazon Mechanical Turk and Other Compensated Crowd Sourcing Sites

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    Crowdsourcing is becoming recognized as a powerful tool that organizations can use in order to get work done, this by freelancers and non-employees. We conceptualize crowdsourcing as a subcategory of outsourcing, with compensated crowdsourcing representing situations in which individuals performing the work receive some sort of payment for accomplishing the organization’s tasks. Herein, we discuss how sites that create a crowd, such as Amazon Mechanical Turk, can be powerful tools for business purposes. We highlight the general features of crowdsourcing sites, offering examples drawn from current crowdsourcing sites. We then examine the wide range of tasks that can be accomplished through crowdsourcing sites. Large online worker community websites and forums have been created around such crowdsourcing sites, and we describe the functions they generally play for crowdsourced workers. We also describe how these functions offer opportunities and challenges for organizations. We close by discussing major considerations organizations need to take into account when trying to harness the power of the crowd through compensated crowdsourcing sites

    The Decomposition of Hydrazine in the Gas Phase and over an Iridium Catalyst

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    Hydrazine is an important rocket fuel, used as both a monopropellant and a bipropellant. This paper presents theoretical results to complement the extensive experimental studies of the gas phase and Ir catalyzed decompositions involved in the monopropellant applications of hydrazine. Gas phase electronic structure theory calculations that include electron correlation predict that numerous molecular and free radical reactions occur within the same energy range as the basic free radical pathways: NN bond breaking around 65 kcal/mol and NH bond breaking around 81 kcal/mol. The data suggest that a revision to existing kinetics modeling is desirable, based on the energetics and the new elementary steps reported herein. A supported Ir6 octahedron model for the Shell 405 Iridium catalyst used in thrusters was developed. Self-Consistent Field and electron correlation calculations (with core potentials and associated basis sets) find a rich chemistry for hydrazine on this catalyst model. The model catalyst provides dramatically lower NN and NH bond cleavage energies and an even smaller barrier to breaking the NH bond by NH2 abstractions. Thus, the low temperature decomposition over the catalyst is interpreted in terms of consecutive NH2 abstractions to produce ammonia and nitrogen. The higher temperature channel, which has hydrogen and nitrogen products, may be due to a mixture of two mechanisms. These two mechanisms are successive NH cleavages with surface H + H recombinations, and the same type of assisted H2 eliminations found to occur in the gas phase part of this study

    Does Methane Invert through Square Planar?

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    MCSCF calculations using a triple-t basis set augmented with diffuse and polarization functions are used to probe that part of the singlet methane potential energy surface that pertains to the inversion of CH4 from one t~trahedral structure t.o another. The true inversion transition state is found to have a distorted C, structure, quite different both ge?me.tncally ~nd energetically from the previously presumed square planar saddle point. At the secondorder configuration mte.ractl~n.level of theory, the barrier to inversion is predicted to be just 7-8 kcaljmol higher in energy than the bond diSSOCiation energy for the first C-H bond cleavage in methane

    Model Space Diabatization for Quantum Photochemistry

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    Diabatization is a procedure that transforms multiple adiabatic electronic states to a new representation in which the potential energy surfaces and the couplings between states due to the electronic Hamiltonian operator are smooth, and the couplings due to nuclear momentum are negligible. In this work, we propose a simple and general diabatization strategy, called model space diabatization, that is applicable to multi-configuration quasidegenerateperturbation theory (MC-QDPT) or its extended version (XMC-QDPT). An advantage over previous diabatization schemes is that dynamical correlation calculations are based on standard post-multi-configurational self-consistent field (MCSCF) multi-state methods even though the diabatization is based on state-averaged MCSCF results. The strategy is illustrated here by applications to LiH, LiF, and thioanisole, with the fourfold-way diabatization and XMC-QDPT, and the results illustrate its validity

    Spin-Orbit Splittings in the Third-Row Transition Elements: Comparison of Effective Nuclear Charge and Full Breit-Pauli Calculations

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    The spin−orbit splittings of low-lying states in third-row transition elements were calculated using both an effective core potential (ECP) method within the one-electron (Zeff) approximation and all-electron (AE) methods using three different approaches. The wave functions were obtained using the multiconfiguration self consistent field (MCSCF) method followed by second-order configuration interaction (SOCI) calculations. All calculated results, except for the ones on atomic Ir, are in reasonable agreement with the corresponding experimental observations. The unsatisfactory results for atomic Ir are attributed to the poor theoretical prediction of the adiabatic energy gap between the lowest two 4F states. This gap has an incorrect sign in AE calculations without scalar relativistic corrections, but the gap can be reproduced qualitatively if these corrections are added using the newly developed RESC (relativistic elimination of small components) scheme. As a result, the AE calculations with the RESC approximation give spin−orbit splittings similar to those obtained by the ECP calculations with the Zeff approximation

    A Comprehensive Analysis of Molecule-Intrinsic Quasi-Atomic, Bonding, and Correlating Orbitals. I. Hartree-Fock Wave Functions

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    Through a basis-set-independent web of localizing orbital-transformations, the electronic wave function of a molecule is expressed in terms of a set of orbitals that reveal the atomic structure and the bonding pattern of a molecule. The analysis is based on resolving the valence orbital space in terms of an internal space, which has minimal basis set dimensions, and an external space. In the internal space, oriented quasi-atomic orbitals and split-localized molecular orbitals are determined by new, fast localization methods. The density matrix between the oriented quasi-atomic orbitals as well as the locations of the split-localized orbitals exhibit atomic populations and inter-atomic bonding patterns. A correlation-adapted quasi-atomic basis is determined in the external orbital space. The general formulations are specified in detail for Hartree-Fock wave functions. Applications to specific molecules exemplify the general scheme

    A Comprehensive Analysis in Terms of Molecule-Intrinsic Quasi- Atomic Orbitals. IV. Bond Breaking and Bond Forming along the Dissociative Reaction Path of Dioxetane

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    The quantitative analysis of molecular density matrices in terms of oriented quasi-atomic orbitals (QUAOs) is shown to yield detailed conceptual insight into the dissociation of dioxetane on the basis of ab initio wave functions. The QUAOs persist and can be followed throughout the reaction path. The kinetic bond orders and the orbital populations of the QUAOs quantitatively reveal the changes of the bonding interactions along the reaction path. At the transition state the OO bond is broken, and the molecule becomes a biradical. After the transition state the reaction path bifurcates. The minimum energy path gently descends from the transition state via a valley–ridge inflection point to a second saddle point, from which two new minimum energy paths lead to two equivalent formaldehyde dimers. The CC bond breaks, and the π-bonds of the formaldehyde fragments form in close vicinity of the second saddle point. The changes of the interactions in this region are elucidated by the analysis of the rearrangements of the QUAOs
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