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Performance on the Constructed Wetlands for Clarification of Sewage Mixed with Secondary-treated Swine WastewaterCheng, Li-lin 18 July 2010 (has links)
The Wu-Luo River, located in the Ping-Tong County of southern Taiwan, has long been polluted by untreated domestic and partially treated swine wastewaters and is among the most polluted rivers in Taiwan. The main objective of this study was to find a practical and effective way to improve water qualities of seriously polluted rivers with a natural technology. The Wu-Luo River was taken as an illustration of the approach in the first subject of this study. The second subject used mixed sewage and a partially-treated swine waster as a simulated polluted river water to test if an UASB (upflow anaerobic sludge blanket) reactor followed by a constructed wetland (CW) system could be used for clarification of the water. For verification of the performance results achieved by the second subject, the third subject used a pilot UASB-CWs system to test the performances by using the water sampled from the Wu-Luo River.
A full-scale constructed wetland system (CWs) has been in operation for cleaning a portion of polluted Wu-Luo River water since January 2005. The first section of study investigated the efficiency and treatment capacity of this full-scale CWs on the river shore, and the operation parameters of CWs could be improved to enhance the treatment.
Due to the limited efficiency and capacity of the full-scale CWs treatment, the second section of this study use a pilot-scale system to treat wastewater mixed in laboratory to simulate the polluted water treatment of the Wu-Luo River. This system was equipped with an UASB reactor in front of the CWs, which is expected to raise the efficiency and capacity of the CWs.
Since the system of UASB-CWs in the second section showed good performance, the actual Wu-Luo River water was introduced to 2 pilot-scale systems which only the experimental one had UASB reactor before CWs in the third section of study. The removal efficiency of pollutants including heavy metals between the experimental and control systems was compared.
In the first section, the Wu-Luo River CWs occupied a total area of 18 hectares in which approximately 9 hectares were wetted by the introduced river water. Close to 4.7 hectares of the CWs was flooded by the river water with 1.9 hectares occupied by emergent and floating plants. A total water volume of about 9,930 m3 was estimated. During the investigation period, 10,000-20,000 m3/d (CMD) (average 10,800 CMD) of the polluted river water was introduced to the CWs with a hydraulic retention time (HRT) of 0.92 day. It was concluded that water sampled from near the midpoint of the CWs got better clarification results than those from the effluent end. Pollutant removal efficiencies were 60, 60, and 67%, respectively, for TCOD, BOD, and SS at the midpoint, and 56, 54, and 45%, respectively, for TCOD, BOD, and SS at the effluent end. Organics, N, and P released from decayed plants were responsible for the poor water qualities at the end. The CWs had only a TN removal efficacy of approximately 18% with no TP removal effect.
In the second section, a pilot system with an UASB reactor combined with two CW reactors was used to evaluate the feasibility of treating wastewater samples (mixture of sewage and partially-treated swine wastewater). To observe the influence of HRT on the removal efficiency of various pollutants in the wastewater in the UASB reactor, 2 phases of experiments with HRTs of 6 and 2 hours were conducted. The UASB reactor responded well in removing most of the pollutants observed except for AN and TP. The average removal efficiency could reach the levels of 93, 91, 86, 89, and 78% for SS, SCOD, SBOD, AN, and TP with the UASB-CWs systems, which have potentials to be used to improve the water quality in river in practice. To observe the influence of HRT on the removal efficiency of various pollutants in the wastewater in the UASB reactor, 2 phases of experiments with HRTs of 6 and 2 hours were conducted.
In the third section, the experimental system was composed of UASB-CW1-CW2 in seris, whereas that of control system was only CW1-CW2 in series. Water samples were taken from Wu-Luo River water. To observe the influence of HRT on the removal efficiency of various pollutants in the river water in the UASB reactor, 3 phases of experiments with HRTs of 6, 4, and 2 hours were conducted. Heavy metals were easily settled in the first section of treatment, the concentrations of them were found higher in the sediments in UASB of experimental system than those in CW1 of control system. UASB can be used for primary sedimentation to prevent the CW1 blocking especially when the river quality changes dramatically on SS. With 4 hrs of HRT in UASB and 32 hrs in CW1 and CW2 each, the removal efficiency is the highest for all pollutants observed in this study. In the effluent of both of the whole systems, more than 96% of SS, NH3, and TN were removed, while more than 70% of COD and TP, more than 60% of BOD were also removed. When HRT in CW1 and CW2 is decreased to be lower than 16 hrs, the ability of CWs to remove TN and TP is also lowered.
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An algebraic approach to the wall characteristic /Cohen, S. D. (Stephen David) January 1969 (has links)
No description available.
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An algebraic approach to the wall characteristic /Cohen, S. D. (Stephen David) January 1969 (has links)
No description available.
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Über Homotopietypen von vierdimensionalen Polyedern /Hennes, Matthias. January 1991 (has links)
Thesis (doctoral)--Rheinische Friedrich-Wilhelms-Universität Bonn, 1991. / Includes bibliographical references (p. 96-98).
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Logical implications between different flavors of asphericity /Biskup, Igor Marko. January 2000 (has links)
Thesis (Ph. D.)--Oregon State University, 2000. / Typescript (photocopy). Includes bibliographical references (leaves 60-63). Also available on the World Wide Web.
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CW Mid-Infrared NH3 LasersKroeker, David 03 1900 (has links)
This thesis describes a series of experiments that were undertaken to extend the limits of output power and wavelength coverage of optically pumped mid-infrared lasers. Initially, two new cw Raman
lasers operating at wavelengths of 11.5 and 12.5 pm were developed. Maximum output powers of 650 add 150 mW were produced, with pump powers of 11 and 3.3 W, respectively. The effect of the pump offset on the output power was then determined by measuring the efficiency of an NH3 laser pumped at frequency offsets of 94 and 274 MHz. In lasers ope rating in pure NH3 the larger pump offset required a greater pump intensity to reach threshold, but efficiency increased with pump offset. Higher NH3 pressures could be used at larger pump offsets and the improved efficiency was attributed to reduced saturation effects at the higher operating pressures. Experiments carried out with NH3 inversion lasers have greatly increased the output powers available at a large number of wavelengths in the 10 to 14 um range. In a buffered NH3 mixture, the sR(5,0) transition was pumped on resonance. Collisions with either N2 or Ar buffer gases were effective in thermalizing the rotational populations in the v2=1 vibrational level and producing gain on a wide range of frequencies. Output powers as large as 3.5 W on a single Tine and greater than 5 W multi-line were produced, at efficiencies of 20 and 30 % respectively. The number of lasing wavelengths increased substantially, as more than forty ortho-NH3 transitions were observed to lase in a grating-tuned cavity. The optical pumping technique was then used for the first time to produce line-tunable lasing on para-NH3 transitions. The sR(5,1) transition was pumped near resonance and 24 para-transitions were observed to lase. In total, lasing was achieved on 65 different transitions in 14NHg, with wave lengths of 10.3 to 13.8 pm. / Thesis / Master of Science (MS)
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CW 266nm all solid state ultraviolet laser resonant cavity Feedback controlTsai, Cheng-Yu 27 June 2000 (has links)
In this work, we use Coherent produced 532nm cw laser as pump source, and 266nm is obtained by frequency doubling. The ring cavity of a laser is generally subject to various perturbation, and the stability of a single-mode laser can be improved by electronically locking its frequency. We use a Pound-Drever-Hall laser frequency stabilization system to control the cavity length. This method utilizes an external phase modulator to produce the sideband and is capable of detecting weak signal to get the information of cavity disturbation. Finally, the signal is dealt with electrical circuit and then feedback to a PZT to control the stabilization of the cavity length.
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The niche network : gender, genre, and the CW brandLausch, Kayti Adaire 25 November 2013 (has links)
In 2006, the merger of the WB and UPN broadcast networks created a new network, the CW. As the fifth major broadcast network, the CW occupies an interesting, hybrid space within the television industry. The CW behaves like a cable channel, yet it usually receives the coverage of a broadcast network. Its target audience is women ages 18 to 34, an extremely small target demographic by any standards. Despite its unique status with the television industry, the CW remains woefully under-studied. This project aims first to provide a context for the CW moment and compare the network's trajectory with that of its predecessors in order to illuminate the myriad of changes that have occurred in the media industries. This project considers how the CW's branding strategies shape perceptions of the network, how the CW brand is produced and how the network's branding practices demonstrate an investment in postfeminism. In order to analyze the CW's branding, this paper examines the network's promotional materials and other paratexts, focusing primarily on print ads, since they are the most circulated. This project also asks how the CW constructs its audience in this age of postfeminism. In order to expose the contradictions and assumptions that underpin the network's project of audience construction, this paper considers both statements from network executives and the network's penchant for reviving 1990s programs with nostalgic appeal. Finally, this paper considers how the category of the "CW show" functions as a genre, and, through textual and narrative analysis, how that genre works to limit the possibilities for female representation on the network. This analysis draws attention to the complicated ways that postfeminist ideas are integrated into young women's programming today, and how conversations about female audiences have changed in the last twenty years. This project draws attention to an as-yet-unstudied site dominated by what Rosalind Gill calls the "postfeminist sensibility" (148). / text
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Estimating the fuel ion dilution in fusion plasmas using neutron emission spectrometryOlsson, Fredrik January 2014 (has links)
Fusion power has the potential to produce clean and safe energy that can contribute significantly to the worlds energy system. The road to this promising energy resource has been long, but with one of the biggest projects in the scientific area that is now on going, a fusion project called ITER, the end of the road is ahead of us. Experiments with a new reactor wall are now in progress at the fusion test reactor JET in Oxford, England. The experiment is a pre study of a possible reactor wall for the new fusion reactor ITER in Cadarache in Provence-Alpes-Côte-d'Azur, France. The ITER like reactor wall (ILW) contains Beryllium and has theoretically favourable properties for achieving better reactor conditions, compared to the old Carbon based wall (CW). One reason for changing the wall is to decrease the fuel dilution, i.e. amount of particles that the reactor wall contributes to the fusion plasma. This is an important factor to minimize; 1% of fuel dilution with Carbon will cause a loss in power up to 12%, while the corresponding value for Beryllium is 8%. For Deuterium fuelled plasmas at JET, the fuel dilution can be quantified by the ratio of the Deuterium and electron densities, nd/ne. In this work, nd/ne is estimated using data from the neutron emission spectrometer TOFOR, along with measurements of the electron density (ne) and temperature (Te). In this report it is investigated how sensitive these fuel dilution measurements are to uncertainties in the measurements of ne and Te. The fuel dilution measurements changed relatively in a span of 10% to 23% when changing Te and ne with 10% in the fuel dilution model. To determine the differences in fuel dilution between the Carbon and ITER like reactor wall, a comparison has to be made between the old reactor wall and the new ILW. To do this, similar plasma scenarios need to be represented during fusion discharges with both walls. In this report, JET’s database is searched through using different search criteria, in order to enable a fair comparison between the walls. The comparison showed a tendency of lower fuel dilution, i.e. cleaner plasmas, for discharges with the ILW, but the data points are quite scattered and the ILW discharges have, in general, a lower temperature than the CW discharges, which makes the comparison difficult. Therefore, it is too early to definitely tell anything about a possible improvement of the fuel dilution levels after the installation of the ILW.
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Finite CW-complexes /Campbell, Harold Edward Alexander, January 1978 (has links)
Thesis (M.Sc.) -- Memorial University of Newfoundland. / Typescript. Bibliography : leaves 55-56. Also available online.
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