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Full-Text Articles in Physical Sciences and Mathematics

On The Kelvin Electrostatic Generator, S. Desmet, F. Orban, Fernande Grandjean Apr 1989

On The Kelvin Electrostatic Generator, S. Desmet, F. Orban, Fernande Grandjean

Chemistry Faculty Research & Creative Works

The Kelvin generator is an amazing electrostatic device which poses many questions. The authors report the results of their investigations of this device under various controlled conditions with both nonpolar and polar liquids and a sodium chloride aqueous solution. They have found that the generator works well even if the two liquid streams originate from different electrically insulated reservoirs. In addition they propose a model in which the electric charge results from the separation of the hydrogen and hydroxyl ions as the water droplets form.


Condensation Coefficient Measurement For Water In The Umr Cloud Simulation Chamber, Donald E. Hagen, John L. Schmitt, Max B. Trueblood, John C. Carstens, Daniel R. White, Darryl J. Alofs Mar 1989

Condensation Coefficient Measurement For Water In The Umr Cloud Simulation Chamber, Donald E. Hagen, John L. Schmitt, Max B. Trueblood, John C. Carstens, Daniel R. White, Darryl J. Alofs

Physics Faculty Research & Creative Works

A systematic series of condensation coefficient measurements of water have been made using the University of Missouri-Rolla cooled-wall expansion chamber which simulates the thermodynamics of cloud. This coefficient is seen to decrease from a value near unity, at the outset of simulation, to a value in the neighborhood of 0.01 toward the end of a simulation. Final values of this coefficient are sufficiently low as to contribute significantly to the broadening of the drop-size distribution in cloud.


Measured Spectra Of The Hygroscopic Fraction Of Atmospheric Aerosol Particles, Darryl J. Alofs, Donald E. Hagen, Max B. Trueblood Feb 1989

Measured Spectra Of The Hygroscopic Fraction Of Atmospheric Aerosol Particles, Darryl J. Alofs, Donald E. Hagen, Max B. Trueblood

Mechanical and Aerospace Engineering Faculty Research & Creative Works

The relation between dry diameter (X0) and critical supersaturation (Sc) for atmospheric submicron aerosol particles is investigated using a long term air sampling program at Rolla, Missouri. The particles are passed through an electrostatic aerosol size classifier, and then through an isothermal haze chamber. Results are reported in terms of an apparent volume fraction of soluble material, εv defined such that for particles composed only of ammonium sulfate and water insoluble compounds, εv is the actual volume fraction of soluble material. The probability distribution of εv is found to be approximately Gaussian in …


Mössbauer Effect Studies Of Nd₂Fe₁₄₋ₓsiₓb And Y₃Fe₁₄₋ₓsiₓb, Oran Allan Pringle, Gary J. Long, G. K. Marasinghe, William Joseph James, Antoni T. Pedziwiatr, W. E. Wallace, Fernande Grandjean Jan 1989

Mössbauer Effect Studies Of Nd₂Fe₁₄₋ₓsiₓb And Y₃Fe₁₄₋ₓsiₓb, Oran Allan Pringle, Gary J. Long, G. K. Marasinghe, William Joseph James, Antoni T. Pedziwiatr, W. E. Wallace, Fernande Grandjean

Physics Faculty Research & Creative Works

No abstract provided.


Morning Increase In Onset Of Ischemic Stroke, John R. Marler, Thomas R. Price, Gregory L. Clark, James E. Muller, Thomas Robertson, Jay P. Mohr, Daniel B. Hìer, Philip A. Wolf, Louis R. Caplan, Mary A. Foulkes Jan 1989

Morning Increase In Onset Of Ischemic Stroke, John R. Marler, Thomas R. Price, Gregory L. Clark, James E. Muller, Thomas Robertson, Jay P. Mohr, Daniel B. Hìer, Philip A. Wolf, Louis R. Caplan, Mary A. Foulkes

Chemistry Faculty Research & Creative Works

The Time of Onset of Ischemic Stroke Was Determined for 1,167 of 1,273 Patients during the Collection of Data by Four Academic Hospital Centers between June 30, 1983, and June 30, 1986. More Strokes Occurred in Awake Patients from 10:00 Am to Noon Than during Any Other 2-Hour Interval. the Incidence of Stroke Onset Declined Steadily during the Remainder of the Day and Early Evening. the Onset of Stroke is Least Likely to Occur in the Late Evening, Before Midnight. © 1989 American Heart Association, Inc.


Determinants Of Early Recurrence Of Cerebral Infarction: The Stroke Data Bank, R. L. Sacco, M. A. Foulkes, J. P. Mohr, P. A. Wolf, D. (Daniel) B. Hier, T. R. Price Jan 1989

Determinants Of Early Recurrence Of Cerebral Infarction: The Stroke Data Bank, R. L. Sacco, M. A. Foulkes, J. P. Mohr, P. A. Wolf, D. (Daniel) B. Hier, T. R. Price

Chemistry Faculty Research & Creative Works

We Studied 1,273 Patients with Ischemic Cerebral Infarction Who Were Entered into the Stroke Data Bank, a Prospective, Observational Study Involving Four University Hospitals and the Biometry and Field Studies Branch of the National Institute of Neurological Disorders and Stroke. Forty Patients Had Non-Iatrogenic Recurrent Stroke within 30 Days after the Index Cerebral Infarction. using Life Tables, the 30-Day Cumulative± SE Risk of Early Recurrence for All Infarctions Was 3.3±0.4%. the Risk of Early Recurrence Was Greatest for Atherothrombotic Infarction (7.9±2.2%, Eight of 113 Patients) and Least for Lacunar Infarction (2.2±1.2%, Eight of 337 Patients). Both Cardioembolic Infarction (4.3±0.9%, 10 …


Predictors Of Survival In Clinically Diagnosed Alzheimer's Disease And Multi-Infarct Dementia, Daniel B. Hier, Joshua D. Warach, Philip B. Gorelick, Joseph Thomas Jan 1989

Predictors Of Survival In Clinically Diagnosed Alzheimer's Disease And Multi-Infarct Dementia, Daniel B. Hier, Joshua D. Warach, Philip B. Gorelick, Joseph Thomas

Chemistry Faculty Research & Creative Works

No abstract provided.


Reversibility Of Ct And Mr Findings In Neuro-Behçet Disease, Dushyant V. Patel, Michael J. Neuman, Daniel B. Hier Jan 1989

Reversibility Of Ct And Mr Findings In Neuro-Behçet Disease, Dushyant V. Patel, Michael J. Neuman, Daniel B. Hier

Chemistry Faculty Research & Creative Works

A Woman with Neuro-Behçet Disease Characterized by Recurrent Attacks of Meningoencephalitis is Reported. during an Attack of Brain Stem Dysfunction Characterized by Dysarthria, Diplopia, and Ataxia, the Postcontrast CT Showed an Enhancing Lesion of the Upper Brain Stem. during a Subsequent Attack Characterized by Subcortical Dementia and Amnesia, Magnetic Resonance (MR) Showed Abnormal Signal Intensity in the Hypothalamus and Upper Brain Stem. Upon Remission of Her Symptoms, Follow-Up Contrast Enhanced CT and MR Were Entirely Normal. Magnetic Resonance is Especially Useful in Localizing Acute Inflammatory Lesions in Behçet Disease. This Case Suggests that Abnormal MR and CT Findings in Neuro-Behçet …


Plasma Polymerization By Magnetron Glow Discharge. I. Effect Of Magnetic Field On Breakdown Of Monomers In Low Pressure, K. Sato, Y. Iriyama, D. L. Cho, H. Yasuda Jan 1989

Plasma Polymerization By Magnetron Glow Discharge. I. Effect Of Magnetic Field On Breakdown Of Monomers In Low Pressure, K. Sato, Y. Iriyama, D. L. Cho, H. Yasuda

Chemistry Faculty Research & Creative Works

The breakdown voltage Vb of glow discharge of an organic monomer generally decreases as the system pressure decreases; however, below a certain threshold pressure, the breakdown voltage increases with decreasing system pressure. In the pressure range below 100 mTorr, the breakdown voltage generally increases as a linear function of 1 /p, where p is the system pressure of the reactor. In this region, glow discharge without magnetic enhancement often yields unstable discharge, which is associated with a very steep slope of a line in the Vh vs /p plot. The similar plots for glow discharges of non-polymer-forming gases, such as …


Polymerization Of Methane, Ashok K. Sharma, H. Yasuda Jan 1989

Polymerization Of Methane, Ashok K. Sharma, H. Yasuda

Chemistry Faculty Research & Creative Works

Plasma polymerization of methane in a magnetically enhanced capacitively coupled bell jar reactor operating at a frequency of 10 kHz is reported. Dependence of polymer deposition rate on monomer feed rate (F), composite power parameter (W/FM), electrode temperature, and electrode cleanliness have been examined. Such functional properties as wettability, adhesion, and thermal stability of the polymer are found to depend on the composite power parameter (W/FM) of the plasma. The permeability studies indicate highly crosslinked nature of the polymer. ESCA studies reveal code position of electrode material with the polymer under high W/FM conditions, potential applications of plasma polymer of …


Measured Spectra Of The Hygroscopic Fraction Of Atmospheric Aerosol Particles, Darryl J. Alofs, Donald E. Hagen, Max B. Trueblood Jan 1989

Measured Spectra Of The Hygroscopic Fraction Of Atmospheric Aerosol Particles, Darryl J. Alofs, Donald E. Hagen, Max B. Trueblood

Mechanical and Aerospace Engineering Faculty Research & Creative Works

The Relation between Dry Diameter (Xo) and Critical Supersaturation (Sc) for Atmospheric Submicron Aerosol Particles is Investigated. the Particles Are Passed through an Electrostatic Aerosol Size Classifier, and Then through an Isothermal Haze Chamber. Results Are Reported in Terms of an Apparent Volume Fraction of Soluble Material, Εv, Defined Such that for Particles Composed Only of Ammonium Sulfate and Water Insoluble Compounds, Εv is the Actual Volume Fraction of Soluble Material. the Probability Distribution of Εv is Found to Be Approximately Gaussian in the Εv Range 0.2 to 1.3. the Mean Εv is 0.5, for Electrostatic Aerosol Classifier Settings of …