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- A report of an investigation of a portion of Strouble's Creek, near Blacksburg, Montgomery County, VirginiaFowle, Bernard H. (Virginia Agricultural and Mechanical College and Polytechnic Institute, 1913)A report of an investigation of a portion of Strouble’s Creek, near Blacksburg, Montgomery County, Virginia, for the purpose of locating a reservoir to serve as a source of ice supply for the Virginia Polytechnic Institute, as a skating pond for the cadets of the Institute and as a possible source of water supply for the Tuberculosis Barns of the Virginia Agricultural Experiment Station, located nearby. This report will include a study of the topography of the portion of trouble's Creek Valley involved, of the water flow conditions of this stream, of complete designs for a Hollow Deck and Buttress Type of Reinforced Concrete Dam, and cost estimates on the proposition. This report will be accompanied by a complete topographic map of the area involved, the field notes, and complete plans for the Hollow Deck and Buttress Type of Dam decided on, save that the 36" pipe and control valve for the drainage of the reservoir are not shown.
- A study of the self-purification of Strouble's CreekSutton, Lee Edwards (Virginia Agricultural and Mechanical College and Polytechnic Institute, 1914)
- Utilization of the Tyndall beam in cellulose processingMyers, Robert Frederick (Virginia Agricultural and Mechanical College and Polytechnic Institute, 1936)no abstract provided by author
- Benefication of soybean oil by use of centrifugeFeagin, William D. (Virginia Agricultural and Mechanical College and Polytechnic Institute, 1939-05-13)Samples of soybean oil were centrifuged in a Sharples supercentrifuge at speeds varying from 15,000 to 45,000 revolutions per minute and with ring dam sizes of #7 to #9 in use in order to determine the effect of centrifuging upon the rancidity, odor, color, and taste of the oil. It was found that most of the rancidity could be removed, the taste improved slightly, the color only slightly changed, and the odor of the soybean oil improved very much. In general, the quality of the oil was made much more desirable although thirty-five per cent of the oil was lost during the process as soap stock.
- Coefficients of heat transfer between condensing alcohol vapors and a vertical copper tubeBuckles, Bennett Douglas (Virginia Agricultural and Mechanical College and Polytechnic Institute, 1940)no abstract provided by author
- Viscose cellophane as a base for a smoking productHampson, Howard Elmer (Virginia Agricultural and Mechanical College and Polytechnic Institute, 1940-09-01)Recognizing that natural tobacco has many undesirable features, such as drying, crumbling, and the nicotine content, this study investigated the properties of a good smoking tobacco and attempted to discover a cellulose base suitable for synthesizing to a smoking product. The review of available literature furnished suggestions for the construction of the smoking apparatus used in this study. A smoking apparatus was constructed and was operated under conditions similar to those found in the human consumption of cigarettes. Standards of human consumption were established and it was found that the average time of consumption was 10.5 minutes, that there was an average interval of 50 seconds between successive inhales, and that the average volume of inhale was 37 c.c. Viscose cellophane was used as a smoking product in cigarettes. Its burning properties were improved by packing it in the cigarettes to an apparent density of 0.381. The burning properties were further improved by treating the cellophane with a three per cent solution of KN03. This batch of cigarettes burned evenly and about half the length of cigarettes usually smoked, indicating that further experimentation in treating viscose cellophane with KN03 might produce a smoking product with ideal burning properties.
- The preparation of an interior varnish from tobacco seed oilGreene, R. Austin (Virginia Agricultural and Mechanical College and Polytechnic Institute, 1942)Tobacco seed oil was expressed from the seed and purified by centrifuging. Four interior varnishes were prepared. Three of these varnishes contained tobacco seed oil as one of the drying oils. A satisfactory interior varnish was prepared using tobacco seed oil, which had been heat-treated at 585ºF for six hours and attained a viscosity of 7.65 poise at 77ºF, and dehydroxylated castor oil at a viscosity of 46.3 poise at 77ºF as the drying oils. This prepared varnish compared favorably to a standard interior varnish when tested for drying time, color, viscosity, and condition of dried film. The viscosity of the standard varnish was 3.1 poise at 77ºF and the viscosity of the prepared varnish was 3.1 poise at 77ºF. The during time of the standard varnish was (1) indoors - 12 hours (2) outdoors - 7 hours. The drying time of the prepared varnish was (1) indoors - 16 hours (2) outdoors - 10 hours.
- The grinding characteristics of laboratory rod millRobertson, Andrew (Virginia Polytechnic Institute, 1944)
- A corrosion measurement testing unit for use with tallolCampbell, C. Langdon (Virginia Tech, 1944-05-05)Although no corrosion measurements have been made, preliminary operation indicates that it is possible to make them under conditions of constant rate of flow of corroding material, composition of corroding material, and temperature.
- A study of the effect of changes of procedure in a standard sulfate determinationBragg, Arthur Dane (Virginia Polytechnic Institute, 1952-06-05)The work done by the author indicates that when %s is determined by gravimetric methods as indicated the volume and concentration of reagents used is very important. It appears that an excess of KBr solution will cause results to be high. An excess of acid in the precipitating solution will cause results to be low.
- A synthesis of 3-acetyl-6-methoxybenzaldehyde utilizing the Fries reactionDuffey, Donald Creagh (Virginia Polytechnic Institute, 1953)Introduction: In the yea.rs since World War II there has been an increasing number of attempts to produce various types of effective herbicides, and as a result of the extensive time and labor required for random testing of synthetic compounds, the search for selective plant-killers has turned toward naturally occurring substances...
- Determination of the mean particle diameter, particle density, and fraction voids of Ottawa sandLuttrell, Robert S. (Virginia Polytechnic Institute, 1955)Fluidization is one of the most recent developments in the field of unit operations. It occurs when particles of solids are maintained in a dense turbulent state by means of a moving fluid. The literature pertaining to fluidization covers only limited operating conditions, and the physical variables in fluidization are the characteristics of the retaining vessel, fluidizing medium, and the particles to be fluidized. The properties of the fluidized solid which are of importance are the size, shape, density, surface tension, and electrostatic charge of the solids, but they have not been fully developed. The purpose of this investigation was to determine the mean particle diameter, particle density, and the fraction voids of Ottawa sand (20-to 30, 30-to 50, and 50-to 70-mesh) to be used in extended studies on fluidization. In the above investigation, the mean particle diameters determined by screen analyses for 20-to 30, 30-to 50, and 50-to 70-mesh Ottawa sand were 0.02530, 0.01691, and 0.00981 inches, respectively. The average particle diameters determined by magnified photographs for 20-to 30, 30-to 50, 50-to 70-mesh Ottawa sand were 0.0278, 0.0191, and 0.0108 inches, respectively. The absolute density of the Ottawa sand was 166.6 pounds per cubic foot. The fraction voids for the 20-to 30, 30-to 50, and 50-to 70-mesh Ottawa sand in the 2-inch diameter tube were 37.1, 38.7, and 41.3 per cent and in the 4-inch diameter tube 38.2, 40.7, and 42.7 per cent, respectively.
- The synthesis of a polythioester from adipic acid and 1,2- ethanedithiolHaworth, William Perry (Virginia Polytechnic Institute, 1958)The purpose of this investigation was to synthesize a polythioester from adipic acid and 1,2-ethanedithiol. Due to the commercial unavailability of 1,2-ethanedithiol it was decided to synthesize 1 t from sodium hydrosulfide and ethylene chloride. Sodium hydrosulfide was prepared by reacting hydrogen sulfide with sodium sulfide in alcohol. In the first test of sodium hydrosulfide were mixed with a stoichiometric amount of ethylene chloride and 200 milliliters of isopropyl alcohol, and for the second teet 45 grams of sodium hydrosulfide were mixed with a stoichiometrlc amount of ethylene chloride tn 200 milliliters of absolute alcohol. Each test was performed at atmospheric pressure in a three-necked, round bottomed, liter flask. The reaction mixture was refluxed for two hours. The result of the experiment was that no 1,2-ethanedithiol was formed.
- Equilibrium data for the system air-acetone-activated carbon at temperatures of 20,27 and 34 degrees C at atmospheric pressureBarkley, William A. (Virginia Polytechnic Institute, 1958)The use of activated carbon for removing color from organic solutions has been known since the seventeenth century. Industrial use of activated carbon as an adsorbent was not possible until 1900 because of inadequate temperature control equipment. Since that time activated carbon has found widespread application in industrial adsorption. The purpose of this investigation was to determine equilibrium data for the system air-acetone-activated carbon at temperatures of 20, 27, and 34ºC at atmospheric pressure. This investigation was carried out at temperatures of 20, 27, and 34ºC at atmospheric pressure, using acetone as the adsorbate and activated carbon as the adsorbent. The adsorption column used was a three inch O.D. pyrex glass column. The amount of adsorption was determined by measuring the change in length of a calibrated quartz spring with a cathetometer, using a constant flow rate of adsorbate. The results of this investigation showed that adsorption of the acetone in activated carbon increased as the concentration of the acetone in air increased, and that there was no significant difference in adsorption at the three test temperatures, 20, 27, and 34ºC, The use of a narrow temperature range and a non-porous bucket for holding the adsorbent is noted. Temperatures above room temperature were not obtainable because of acetone condensation on the quartz spring and bucket.
- Properties of the system triethylene glycol dimethyl ether- benzene-water at 30⁰CCarr, Walter A. (Virginia Polytechnic Institute, 1962)The purpose of this investigation is to determine the density, viscosity, surface and interfacial tension, diffusivity, and refractive index of a system or benzene water containing triethylene glycol dimethyl ether at 30ºC. The samples were prepared by adding the E-161 to solutions of benzene saturated with water and solutions of water saturated with benzene to form a system of total E-161 concentration between 0 and 69 weight per cent. The samples were allowed to come to thermal equilibrium in a constant temperature bath at 30ºC. The density of the samples was determined with a pycnometer, the viscosity with an Ostwald viscosimeter, the refractive index with a dipping refractometer, the surface and interfacial tensions with the Cenco-du Nouy tensiometer, and the diffusivity was calculated by the method of Wilke. It was found that density, viscosity, refractive index, surface and interfacial tension, and diffusivity at any point in the E-161-benzene-water system depends on the concentration of E-161, benzene, and water at that point. The curve of densities, viscosities, refractive indices, surface tensions, and diffusivities of solutions in the benzene phase approach the curve of densities., viscosities, refractive indices, surface tensions and diffusivities or solutions in the water phase as the E-161 concentration is increased to the plait point concentration. The E-16 becomes a “surface active” agent when dissolved in the water phase and tends to lower the surface tension of this phase; the E-161 becomes a “surface inactive” agent when dissolved in the benzene phase has only a slight effect on the surface tension of this phase. The interfacial tension between benzene and water phase is decreased as the concentration of E-161 in the system is increased to the plait point concentration where the interfacial tension is zero. The diffusivity was found to decrease with increased concentration of E-161.
- Frequency response of a feed preheaterJanis, Rudolph Francis (Virginia Polytechnic Institute, 1962)The purpose of this investigation was to measure the frequency response of a shell and tube heat exchanger when the input is the pressure to the steam valve and the output is the feed temperature. During this investigation the frequency response of the feed flow loop was also determined. Controller settings were determined for the feed rate controller. The heat-exchanger under investigation was the food preheater connected to the ten place, bubble-cap, distillation column located in the Unit Operations Laboratory, Department of Chemical Engineering, Virginia Polytechnic Institute. This heat-exchanger was a single-pass, shell and tube type having a contact surface of nineteen 5/8-inch copper tubes 45.5 inches long. The flow rate during the investigation of temperature and pressure frequency response was maintained at 3.70 gallons per minute. The feed mixture was composed of benzene, n-hepane, xylene, and toluene. Frequency response tests were conducted on the steam pressure and hydrocarbon temperature to upsets in steam flow rates. Two tests were conducted on each the temperature and pressure. The first test was conducted at a mean temperature of 161°F and the second at 194°F. The frequency range for each of these tests was 0.008 - 0.05 cycles per second. The ultimate frequency of the hydrocarbon temperature to steam flow upsets was determined to be 0.021 cycles per second. Frequency response test performed on the feed flow loop was conducted at a mean hydrocarbon flow rate of 2.75 gallons per minute and room temperature. A fifteen percent disturbance was used and the unit was tested over the frequency range of 0.008 - 0.6 cycles per second. The zero frequency gain of the feed flow loop was found to be 2.10. The ultimate frequency for upsets in flow was determined to be 0.53 cycles per second. The controller settings determined for the two mode controller which controlled the hydrocarbon flow were, proportional band of 63.5 percent and reset of 0.262 minutes.