2,015 research outputs found

    The determination of ethanol in aqueous solution by gas-liquid partition chromatography

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    The present chemical and physical methods for the determination of ethyl alcohol are all subject to systematic errors derived from any of a number of interfacing substances usually present in solution with the ethanol. Some of the most popular methods are slow and tedious and require a good deal of skill and technique to perform. The dichromate (2), pycnometer and refractometer methods are three such methods. The interfering substances most often present in industrial and food products are fusel oils and acetaldehyde. These substances interfere in the three methods just mentioned. It is of course possible to analyze for these substances separately and then make appropriate corrections, or to remove them before the determination is performed; but by either method the total analysis time is quite lengthy and tedious. In many cases throughout industry the determination of ethyl alcohol is a routine analysis which is usually performed by lab technicians with limited chemical background and thus lengthy and difficult methods of analysis should be minimized. The ideal method would be one which is rapid, accurate, specific and one which can be performed easily by a skilled technician. Gas chromatography is an analytiucal tool which has not yet been thoroughly investigated as a means of determining ethanol in aqueous solutions and is one which can virtually eliminate many of the undesirable features of the present chemical and physical methods. It is the purpose of this thesis to add to this investigation by presenting a moderately rapid gas chromatographic method and a high speed gas chromatographic method for this analysis and to compare these to the pycnometer and micro-dichromate methods presently used. The purpose of presenting two methods is to provide the user some choice depending on his needs and facilities

    Experimental study of the flow field inside a whirling annular seal

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    The flow field inside a whirling annular seal was measured using a 3-D Laser Doppler Anemometer (LDA) system. The seal investigated has a clearance of 1.27 mm, a length of 37.3 mm, and is mounted on a drive shaft with a 50 percent eccentricity ratio. This results in the rotor whirling at the same speed as the shaft rotation (whirl ratio = 1.0). The seal is operated at Reynolds number of 12,000 and a Taylor number of 6,300 (3,600 rpm). The 3-D LDA system is equipped with a rotary encoding system which is used to produce phase averaged measurements of the entire mean velocity vector field and Reynolds stress tensor field from 0.13 mm upstream to 0.13 mm downstream of the seal. The mean velocity field reveals a highly three dimensional flow field with large radial velocities near the inlet of the seal as well as a recirculation zone on the rotor surface. The location of maximum mean axial velocity migrates from the pressure side of the rotor at the inlet to the suction side at turbulence kinetic energy. However, turbulence production and dissipation attain equilibrium fairly quickly with remaining relatively constant over the last half of the seal

    Turbulence measurements of high shear flow fields in a turbomachine seal configuration

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    The mean velocity and Reynolds stress tensor throughout a whirling annular seal are presented. The data was collected with a three dimensional laser Doppler velocimeter using phase averaging. Two axial flow conditions (Re = 12,000 and 24,000) were studied at one shaft speed (Ta = 6,600). The eccentricity and whirl ratios were 50 and 100 percent, respectively. There is a region of high axial momentum in this region is higher in the low Reynolds number case due to an axial recirculation zone that occurs on the suction side of the rotor at the inlet. The recirculation zone does not occur in the high Reynolds number case. At both Reynolds numbers, there is a recirculation zone on the rotor surface in the pressure side of the inlet. This recirculation zone extends from 20 to 200 degrees rotor zenith in the tangential direction, and is one third of a clearance wide radially. The high Reynolds number recirculation zone is 1.5 mean clearances long, while the low Reynolds number zone extends 2 mean clearances downstream. When compared to previous studies, it is apparent that the tangential momentum is no greater for a seal with whirl than for one without if other parameters are constant. Areas of high tangential momentum occur in the clearance where the axial momentum is low. Average exit plane tangential velocities in the high Reynolds number case are 1.5 times greater than those in the other flow case. These results are in general agreement with predictions made by other investigators

    An experimental technique for performing 3-D LDA measurements inside whirling annular seals

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    During the last several years, the Fluid Mechanics Division of the Turbomachinery Laboratory at Texas A&M University has developed a rather unique facility with the experimental capability for measuring the flow field inside journal bearings, labyrinth seals, and annular seals. The facility consists of a specially designed 3-D LDA system which is capable of measuring the instantaneous velocity vector within 0.2 mm of a wall while the laser beams are aligned almost perpendicular to the wall. This capability was required to measure the flow field inside journal bearings, labyrinth seals, and annular seals. A detailed description of this facility along with some representative results obtained for a whirling annular seal are presented

    Scalar capital as ingredient of success in conservation governance: evidence from Melanesia

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    Problems of scale abound in the governance of complex social-ecological systems. Conservation governance, for example, typically occurs at a single scale, but needs to inform governance and action at other scales to be truly effective at achieving social and ecological outcomes. This process is conventionally conceived as unidirectional - either scaling down or scaling up - in the way it both exploits and creates the natural, social, human, institutional, and financial resources and benefits that are collectively known as conservation 'capital'. Here we analyse multiscale conservation governance and the different types of capital that impede or facilitate its effectiveness. Comparative analysis of conservation planning in Papua New Guinea and the Solomon Islands, through in-depth document review, key informant interview, and participant observation, reveals limited evidence of unidirectional processes. Instead, we observe multidirectional scaling pathways, cultivated by the following six scale-explicit characteristics of effective conservation governance: 1) multiscale understanding, 2) scale jumping, 3) scaled leadership characteristics, 4) scaled stakeholder engagement, 5) scaled policy frameworks, and 6) scaled institutional settings. While the latter four are familiar concepts, though not always recognised as explicitly scalar, we know little about the first two attributes of conservation governance. Based on this novelty and relevance, we propose a new form of capital - 'scalar capital' - to complement natural, social, human, institutional, and financial capitals as both input and outcome of effective conservation governance. We find that scalar capital facilitates flows of different resources (data, conservation objectives, practitioner experience, institutional support, and funding) in multiple directions. Critically, we present empirical evidence that conservation governance can foster scalar capital to improve outcomes across multiple scales

    Planetary astronomy

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    The authors profile the field of astronomy, identify some of the key scientific questions that can be addressed during the decade of the 1990's, and recommend several facilities that are critically important for answering these questions. Scientific opportunities for the 1990' are discussed. Areas discussed include protoplanetary disks, an inventory of the solar system, primitive material in the solar system, the dynamics of planetary atmospheres, planetary rings and ring dynamics, the composition and structure of the atmospheres of giant planets, the volcanoes of IO, and the mineralogy of the Martian surface. Critical technology developments, proposed projects and facilities, and recommendations for research and facilities are discussed

    The Prosecution of Child Sexual Abuse in Idaho: July 1, 2006 - June 30, 2007

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    House Bill 362, passed in 1989 (adding section 67-1405 to the Idaho Code), expanded the Attorney General\u27s duties to require preparation of an annual report to be submitted to the legislature reporting the incidence of felony child sex abuse charges filed in adult and juvenile courts in the state. A research team from Research, Training, and Evaluation Associates worked in conjunction with the Offices of the Governor and the Attorney General to collect data and prepare the report to comply with this legislation. This team has collected data for the past seventeen reports. Specifically, data were collected on site on child sex abuse cases filed in district and juvenile courts throughout the state for the period of July 1, 2006 to June 30, 2007. The data were analyzed by the research team and submitted to the Offices of the Attorney General and the Governor for review. Governor Butch Otter and Attorney General Lawrence Wasden submitted the completed report to the legislative leadership
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