4,200 research outputs found

    OCD and Philosophy: Short Papers on OCD, Psychopathy, and Psychopathology

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    Short papers on OCD, philosophy, psychopathy, psychopathology generally, and their interrelations

    The Economics of Higher Education in the 21st Century

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    In the first part of this two-part work, the economics of higher education are explained. It is made clear how a university’s business model differs from that of a company that has to compete on the open market. On this basis, it is explained: (i)Why universities are in no way threatened by low retention-rates and graduation-rates; (ii)Why universities cannot significantly improve or otherwise alter the quality of their educational services without imperiling their very existences; (iii)Why universities do not have to improve the quality of their educational services; (iv)Why universities couldn’t improve the quality of their services even if they wanted to; (v)Why the fact that many universities have low retention- and graduation-rates does not a represent a business opportunity, or opportunity of any other kind, for anyone, whether inside or outside of academia; and (vi)Why principles of Knowledge Management (KM) that are so useful when it comes to helping businesses that compete on the open market are completely useless, and indeed of negative utility, when it comes to helping universities solve their problems. In the second part of this work, it is explained how to construct an online university that is both lucrative and also provides instruction that is faster, better, cheaper, and more useful than the instruction provided by any existing (or possible) brick-and-mortar university. Finally, it is explained how the principles of KM can be used to optimize such a university, once it is up and running

    A model for a countercurrent gas—solid—solid trickle flow reactor for equilibrium reactions. The methanol synthesis

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    The theoretical background for a novel, countercurrent gas—solid—solid trickle flow reactor for equilibrium gas reactions is presented. A one-dimensional, steady-state reactor model is developed. The influence of the various process parameters on the reactor performance is discussed. The physical and chemical data used apply to the case of low-pressure methanol synthesis from CO and H2 with an amorphous silica—alumina as the product adsorbent. Complete reactant conversion is attainable in a single-pass operation, so that a recycle loop for the non-converted reactants is superfluous.\ud \ud In the following article the installation and experiments for which this theory was developed will be described

    Kant's Arguments for God's Existence

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    A clear and concise exposition and critique of Kant's arguments for God's existenc

    Binary vapour—liquid equilibria of methanol with sulfolane. Tetraethylene glycol dimethyl ether and 18-crown-6 = Phasengleichgewichte in binären systemen von Methanol mit Sulfolan, Tetraethylenglycoldimethylether und 18-krone-6 Kronenether

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    The activity coefficients of methanol in sulfolane, tetraethylene glycol dimethyl ether (TEGDME) and 18-crown-6 under conditions of equilibrium have been determined in the temperature range 423–503 K and in the pressure range 0.28–3.5 MPa. A minimum in the activity coefficient was found for the methanol—TEGDME and methanol—18-crown-6 solutions

    The kinetics of the methanol synthesis on a copper catalyst: An experimental study

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    The kinetics of the low pressure of methanol from feed gases containing solely CO and H2 were studied in an internally recycled gradientless reactor. As experimental accuracy impeded the application of high CO contents, the experimental range of mole fraction of CO was limited to 0.04 to 0.22. The total pressure was varied from 3 to 7 MPa and the temperature from 503 to 553 K. Residence time distribution experiments confirmed the assumption of perfect mixing on a macroscale. A maximum likelihood approach was used to fit possible kinetic equations. Although more accurate results and better fits—compared to previous experiments in a simple integral reactor—were obtained, no single rate expression could be selected as the most appropriate one. This was mainly attributed to the effects of small amounts of CO2 and H2O formed in the reactor. Three different reaction rate equations fit the experiments equally well. Arguments are given that we never can expect to elucidate the reaction mechanisms on the basis of kinetic experiments

    Gas-solid trickle flow hydrodynamics in a packed column

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    The pressure gradient and the static and the dynamic hold-up have been measured for a system consisting of a Fluid Cracking Catalyst (FCC) of 30–150 × 10−6 m diameter, trickling over a packed bed and with a gas streaming in countercurrent flow. The experiments were carried out at ambient conditions using a glass column of 25 × 10−3 m diameter. The packing material consisted of 8 × 8 × 3 mm ceramic Raschig rings, a mixture of 7 × 7 × 1 mm glass Raschig rings and 5 × 5 mm catalyst pellets and of stacked Kerapak ceramic mixing units of Sulzer, each unit 50 mm long and 25 mm in diameter. Four different gases have been tested. A correlation for the pressure gradient in the preloading region is derived based on the Ergun equation and taking into account the internal gas recirculation due to the solids trickles. The void fraction of the trickles is found to be independent of the physical properties of the gas phase. The behaviour of the GSTF-system in the preloading regime and the phenomena of loading and flooding are discussed. A correlation is given which relates the boundary between preloading and loading with the particle and gas properties and the solids flow rate

    Research program to determine rotor response characteristics at high advance ratios Final report

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    Stability and response characteristics of directly controlled rigid rotors at high advance ratios and correlation of mathematical model with wind tunnel test dat

    Dielectric relaxation in chevron surface stabilized ferroelectric liquid crystals

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    The dielectric response of surface stabilized ferroelectric liquid crystals with chevron layer structure is studied within low and intermediate frequency ranges, characteristic for collective molecular excitations. By analytically solving the dynamic equation for collective molecular fluctuations under a weak alternating electric field, it is demonstrated that chevron cells stabilized by both nonpolar and polar surface interactions undergo at medium frequencies two Debye relaxation processes, connected with two chevron slabs, on opposite sides of the interface plane. This result is confirmed, experimentally, making use of the electro-optic technique. Based on qualitative arguments supported by microscopic observations of zigzag defects at different frequencies and amplitudes of the external electric field, it is shown that, at low frequencies, the electro-optic response of chevron samples is determined by three kinds of motions of zigzag walls. The first two dynamic categories are related to collective relaxation processes at weak fields, within smectic A layers forming zigzag walls, and drift or creep motions of thick walls occuring at stronger field amplitudes. Dynamic processes of the third kind correspond to sliding of zigzag walls, which appear at yet stronger field amplitudes, but below the switching threshold.Comment: 9 pages 10 figure
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