3,719 research outputs found

    Social Sector Business Ventures: The Critical Factors That Maximize Success

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    This paper seeks to help social sector leaders understand the factors that they should consider when launching revenue-generating business ventures. Given that much of the research on social sector business ventures is based on the personal experiences of individual practitioners, there is a wide array of advice for organizational leaders who are thinking about launching business ventures. Consequently, we approach the subject of social sector business ventures in a systematic and analytic way in order to determine what organizational leaders really need to know about launching successful ventures. We introduce a framework called "business in a box" that separates the process of thinking about launching business ventures from the organizational characteristics and dynamics that influence these ventures. We assert that organizational leaders who wish to maximize the success of their business ventures must explore (1) what is "inside" the box (The Business and its Context) to understand the business fundamentals of launching a venture and (2) what is "outside" the box (Assets and Internal Destructive Forces) to understand the forces and dynamics within the organizational context that impact these ventures.This publication is Hauser Center Working Paper No. 43. The Hauser Center Working Paper Series was launched during the summer of 2000. The Series enables the Hauser Center to share with a broad audience important works-in-progress written by Hauser Center scholars and researchers

    Combustion system processes leading to corrosive deposits

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    Degradation of turbine engine hot gas path components by high temperature corrosion can usually be associated with deposits even though other factors may also play a significant role. The origins of the corrosive deposits are traceable to chemical reactions which take place during the combustion process. In the case of hot corrosion/sulfidation, sodium sulfate was established as the deposited corrosive agent even when none of this salt enters the engine directly. The sodium sulfate is formed during the combustion and deposition processes from compounds of sulfur contained in the fuel as low level impurities and sodium compounds, such as sodium chloride, ingested with intake air. In other turbine and power generation situations, corrosive and/or fouling deposits can result from such metals as potassium, iron, calcium, vanadium, magnesium, and silicon

    Absolute flux measurements for swift atoms

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    While a torsion balance in vacuum can easily measure the momentum transfer from a gas beam impinging on a surface attached to the balance, this measurement depends on the accommodation coefficients of the atoms with the surface and the distribution of the recoil. A torsion balance is described for making absolute flux measurements independent of recoil effects. The torsion balance is a conventional taut suspension wire design and the Young modulus of the wire determines the relationship between the displacement and the applied torque. A compensating magnetic field is applied to maintain zero displacement and provide critical damping. The unique feature is to couple the impinging gas beam to the torsion balance via a Wood's horn, i.e., a thin wall tube with a gradual 90 deg bend. Just as light is trapped in a Wood's horn by specular reflection from the curved surfaces, the gas beam diffuses through the tube. Instead of trapping the beam, the end of the tube is open so that the atoms exit the tube at 90 deg to their original direction. Therefore, all of the forward momentum of the gas beam is transferred to the torsion balance independent of the angle of reflection from the surfaces inside the tube

    Thermochemical analyses of the oxidative vaporization of metals and oxides by oxygen molecules and atoms

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    Equilibrium thermochemical analyses are employed to describe the vaporization processes of metals and metal oxides upon exposure to molecular and atomic oxygen. Specific analytic results for the chromium-, platinum-, aluminum-, and silicon-oxygen systems are presented. Maximum rates of oxidative vaporization predicted from the thermochemical considerations are compared with experimental results for chromium and platinum. The oxidative vaporization rates of chromium and platinum are considerably enhanced by oxygen atoms

    Electron Densities from Gas‐Phase Electron Diffraction Intensities. II. Molecular Hartree–Fock Cross Sections

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    Differential cross sections for electron scattering based on molecular Hartree–Fock electron densities are compared with cross sections based on the independent‐atom approximation for the molecules C2, N2, O2, F2, and CO. The results show that bonding effects on the electron density manifest themselves to the extent of several percent in the scattered intensity at small scattering angles. Furthermore, molecule‐to‐molecule variations in the shifts of electron density are clearly reflected in variations in the functional form of the scattered intensity. A comparison of the calculated intensities for N2 and O2 with preliminary experimental intensities suggests that electron scattering techniques now in development should be able to provide information about bonding and electron correlation effects competitive in accuracy with that of current quantum‐mechanical calculations.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/70136/2/JCPSA6-51-7-2896-1.pd

    Electron Densities from Gas‐Phase Electron Diffraction Intensities. I. Preliminary Considerations

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    The intensity of electrons and x rays scattered by a freely rotating molecule is determined, in the kinematic approximation, solely by the nuclear–nuclear, electron–nuclear, and electron–electron radial distribution functions of the molecule. Although these functions are one‐dimensional, the latter two contain some information about the three‐dimensional distribution of electrons in the molecule because the electrons are distributed relative to several nuclear reference positions and the spatial distribution of the nuclei is known. The purpose of this series of papers is to investigate the extent to which this information can be deciphered. Although published accounts have purported to show that the electron density ρ(r)ρ(r) can be determined uniquely from the scattered intensity, we demonstrate that, in fact, the transfomation is not unique. Nevertheless, if certain, not unreasonable, restrictions are imposed upon the form of ρ(r)ρ(r), it becomes possible to make fairly detailed inferences about the three‐dimensional character of the density. We propose a procedure which, although not guaranteeing a unique transformation, provides a means for deriving chemically significant knowledge about the molecular electron density from experimental gas‐phase intensities.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/69800/2/JCPSA6-51-7-2891-1.pd

    Theoretical and experimental studies of the deposition of Na2So4 from seeded combustion gases

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    Flames in a Mach 0.3 atmospheric pressure laboratory burner rig were doped with sea salt, NaS04, and NaCl, respectively, in an effort to validate theoretical dew point predictions made by a local thermochemical equilibrium (LTCE) method of predicting condensation temperatures of sodium sulfate in flame environments. Deposits were collected on cylindrical platinum targets placed in the combustion products, and the deposition was studied as a function of collector temperature. Experimental deposition onset temperatures checked within experimental error with LTCE-predicted temperatures. A multicomponent mass transfer equation was developed to predict the rate of deposition of Na2SO4(c) via vapor transport at temperatures below the deposition onset temperature. Agreement between maximum deposition rates predicted by this chemically frozen boundary layer (CFBL) theory and those obtained in the seeded laboratory burner experiments is good

    Теплогидравлический расчёт ТВС ИРТ-3М в реакторе ИРТ-Т с различными поверхностями теплообмена

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    The master’s thesis has attempted to model thermal-hydraulic behavior of the fuel assembly of IRT-3M type of IRT-T reactor with various heat-conductivity surfaces.В магистерской диссертации приведено теплогидравлическое моделирование ТВС типа ИРТ-3М реактора ИРТ-Т с различными поверхностями теплообмена
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