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Bremsstrahlung Luminosity Monitoring for SCRIT Project (Report part 1)Lundkvist, Niklas January 2011 (has links)
The purpose of the SCRIT project is to determine size and shape of short-lived and rarely-produced nuclei by elastic electron scattering, which is the best probe for the structure studies, for the first time. In traditional electron scattering, a solid target having an order of 1023 nuclei/cm^2 is normally used, which is not possible for short-lived and rarely-produced nuclei. In this project a Self Containing Radioactive Isotope Target scheme (SCRIT) is going to be employed. This innovative ion-trap method is shown to be a way to make measurements with a very small amount of nuclei, an order of only 106 nuclei. In order to determine the absolute cross section for elastic electron scattering for structure study, the simulates measurement of the bremsstrahlung from the trapped nuclei is required. Since the bremsstrahlung cross section for a nucleus of the atomic number Z is well know, the precise measurement of the bremsstrahlung provides the luminosity. My theme in this SCRIT project was a construction of a bremsstrahlung luminosity monitor. It consists of a position monitor for measuring the spatial distribution of bremsstrahlung and a Pb-glass Cerenkov detector for energy measurement. My efforts have been mainly devoted to the construction of a position monitor system using fiber scintillators. The construction of the position monitor was divided into five parts; detector construction, support construction, trigger detector construction, software programming, software testing and detector tests. The position monitor consists of two sets of fiber scintillation detectors. Each of them uses 16 fibers, Bicron BCF-10 with a cross section of 2x2mm^2, optically coupled to a multi-anode photomultiplier, (Hamamatsu H6568-10). The position monitor can measure the XY distribution of bremsstrahlung. Strictly speaking, the fiber detector detects not bremsstrahlung directly but electrons and/or positrons by pair creation of bremsstrahlung in a materials. The data acquisition system has been programmed in NI LabVIEW. The software is an advanced X/Y-coordinate counting system, which can additionally preform functions as save data to file and 3D-plot to determine the spreading of the bremsstrahlung luminosity. The results can be saved and transferred online to a server so that is possible to access the data from anywhere. The system has been tested using beta rays from 90Sr source. The results of the test shown that the detectors can detect minimum ionizing particle, i.e. electrons and positrons. The detector and software testings shows that the system is ready to use for luminosity measurements at SCRIT experiment. This system I constructed surely provides a new and useful information for the SCRIT experiments. / SCRIT Project
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Experiments on the Rarefaction Wave Driven Rayleigh-Taylor InstabilityMorgan, Robert Vaughn January 2014 (has links)
Experiments are presented in which the diffuse interface between two gases is made Rayleigh-Taylor unstable by interaction with a rarefaction wave. The apparatus used consists of a test section where the counter-flow of light and heavy gases generates a diffuse, stably stratified interface. A tank attached to the bottom of the apparatus is evacuated, and when an appropriate pressure is reached, the interface is perturbed using either a horizontal or a vertical oscillation technique to produce 2D, 3D, and multi-mode perturbations. A solenoid plunger fires an arrowhead which ruptures a membrane, generating a rarefaction wave that travels upward toward the interface. When the rarefaction wave impacts the interface, the interface accelerates down toward the vacuum tank, and the Rayleigh-Taylor instability and mixing develop in the test section. The instability evolution and mixing are recorded using high-speed CMOS cameras and planar laser Mie scattering of smoke particles seeded in the heavy gas. Additional visualization is undertaken with a high-speed shadowgraph system using three CMOS cameras. Interface diffusion thicknesses are recorded using the Rayleigh scattered light of an unexpanded laser beam. Simulations are conducted using a 1D numerical characteristics code based on the method of Hoskin (Meth. Comp. Physics, 3, 1964), and using the LLNL research hydrodynamics code Miranda (Cook, Phys. Fluids, 19, 2007). This 1D code produces Lagrangian interface trajectories while the 2D and 3D simulations using Miranda calculate the growth of perturbations. The theory of Chandrasekhar (Chandrasekhar, Proc. Camb. Phil. Soc., 51, 1955) is extended to capture the effects of diffuse interfaces while including viscosity, and dispersion curves are solved for numerically using a Riccati technique. These solutions show that the method of Duff et al. (Phys. Fluids, 5, 1962) may not accurately describe the growth of single modes for large wavenumbers. For large wavenumbers, when the interface has a large diffusion thickness, perturbations are found to grow with the linear growth rate n = 2Ag/(√πv₀δk²), where A is the Atwood number, g is the acceleration, v₀ is the average kinematic viscosity, δ is the thickness of the interface, and k is the wavenumber of the perturbation. Flat interface experiments exhibit predictable acceleration profiles, but the tail of the rarefaction wave appears at late times reducing the duration of acceleration. Single-mode experiments are conducted for four Atwood numbers including CO₂/SF₆ with A = 0.49, Air/SF₆ with A = 0.63, He/CO₂ with A = 0.82, and He/SF₆ with A = 0.94. Early time results compare well with linear stability theory when non-constant acceleration and diffusion thickness are accounted for. Simulations show good agreement with experiments into the non-linear growth phase. The CO₂/SF₆ and Air/SF₆ experiments show terminal velocity behavior where buoyancy is balanced by drag, but produce Froude numbers larger than those predicted by the Goncharov model (Phys. Rev. Lett., 88, 2002). Using the Mikaelian model (Phys. Fluids, 21, 2009), improved asymptotic Froude numbers are found. The He/CO₂ and He/SF₆ experiments exhibit free-fall behavior, accelerating freely without external forces, with spike amplitudes proportional to the displacement of the unperturbed interface. Single-mode experiments conducted with 3D perturbations using CO₂/SF₆ and Air/SF₆ show good agreement with linear stability theory when non-constant acceleration and diffusion thickness are accounted for. Simulations and the model of Mikaelian predict the growth of the spikes up until late time, while the 3D bubbles reach a terminal velocity more quickly than in simulations. Multi-mode experiments were conducted using Air/SF₆. Multi-mode experiments exhibit nearly t² growth at early times which decays. Using extraction techniques that account for variable acceleration, alpha values are found between ɑ = 0.02 and ɑ = 0.04. These alpha values are lower than are seen for most experiments, but are similar to ɑ values seen in miscible experiments.
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Investigations of water and tracer movement in covered and uncovered unsaturated waste rockMarcoline, Joseph R. 11 1900 (has links)
A better understanding of the hydrogeology of mine waste rock and cover systems is essential for the quantification, prediction and reduction of metals loading to the receiving environment. A series of experiments were conducted on an instrumented intermediate-scale waste rock pile at the Cluff Lake Mine in Saskatchewan to investigate the changes in flow and solute transport within coarse waste rock under three different surface conditions. Following these studies, the waste rock pile was deconstructed, structures were mapped, and samples were collected for physical characterization and pore water extraction. The internal structure of the waste rock pile was more important than the texture and topography under the free-dumped and ripped/leveled surface, while the surface condition was found to be the dominant control on spatial and temporal variability of outflow from the waste rock with the covered surface. Data from a deuterium tracer test, lysimeter outflow, and from TDR probes were used to derive estimates of the maximum and an average pore water velocity through the uncovered and the covered waste rock. An average pore water velocity through the matrix materials of the uncovered waste rock was approximately 1.5 m/yr and maximum preferential flow velocities were as high as 5 m/day. The post-cover pressure wave velocity of 0.1 to 1 m/day is inferred from outflow and TDR data, and average pore water velocities (0.39 m/y and 0.73 m/y) are calculated by the water flux and tracer methods, respectively. The distribution of the tracers in pore water and the internal structure were mapped during a detailed deconstruction of the waste rock pile and attempts were made to link the data to the spatial and temporal patterns of lysimeter outflow. The pore water chloride concentrations and the deuterium values did not provide conclusive data necessary to link the spatial and temporal patterns observed in the lysimeter hydrographs to internal structure; however, it provided insight into the internal flow mechanisms and water residence times.
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基礎励振を受ける並進・傾き連成系の振動(オートパラメトリック共振と重心高さ、偏重心、剛性差の影響)井上, 剛志, INOUE, Tsuyoshi, 石田, 幸男, ISHIDA, Yukio, 山田, 晋太郎, YAMADA, Shintarou 08 1900 (has links)
No description available.
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Investigations of water and tracer movement in covered and uncovered unsaturated waste rockMarcoline, Joseph R. 11 1900 (has links)
A better understanding of the hydrogeology of mine waste rock and cover systems is essential for the quantification, prediction and reduction of metals loading to the receiving environment. A series of experiments were conducted on an instrumented intermediate-scale waste rock pile at the Cluff Lake Mine in Saskatchewan to investigate the changes in flow and solute transport within coarse waste rock under three different surface conditions. Following these studies, the waste rock pile was deconstructed, structures were mapped, and samples were collected for physical characterization and pore water extraction. The internal structure of the waste rock pile was more important than the texture and topography under the free-dumped and ripped/leveled surface, while the surface condition was found to be the dominant control on spatial and temporal variability of outflow from the waste rock with the covered surface. Data from a deuterium tracer test, lysimeter outflow, and from TDR probes were used to derive estimates of the maximum and an average pore water velocity through the uncovered and the covered waste rock. An average pore water velocity through the matrix materials of the uncovered waste rock was approximately 1.5 m/yr and maximum preferential flow velocities were as high as 5 m/day. The post-cover pressure wave velocity of 0.1 to 1 m/day is inferred from outflow and TDR data, and average pore water velocities (0.39 m/y and 0.73 m/y) are calculated by the water flux and tracer methods, respectively. The distribution of the tracers in pore water and the internal structure were mapped during a detailed deconstruction of the waste rock pile and attempts were made to link the data to the spatial and temporal patterns of lysimeter outflow. The pore water chloride concentrations and the deuterium values did not provide conclusive data necessary to link the spatial and temporal patterns observed in the lysimeter hydrographs to internal structure; however, it provided insight into the internal flow mechanisms and water residence times.
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Temporal trends in the medical treatment of unstable angina, 1990-1995, and health outcomes associated with beta-blocker and diltiazem treatment of unstable angina /Smith, Nicholas Lannon. January 1997 (has links)
Thesis (Ph. D.)--University of Washington, 1997. / Vita. Includes bibliographical references (leaves [65]-76).
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A comparison of oxygen consumption, RPE and lower limb EMG activity in toning versus running shoes on uphill, level and downhill walkingChatha, Avneet 29 August 2013 (has links)
OBJECTIVES: Comparing electromyography and physiological measures while walking on various inclines in unstable and stable shoes.
METHODS: Eleven healthy females walked on treadmill at +10%, 0% and -10% grade for five minutes each, at self-selected pace, in stable and unstable shoes. The two sessions were done 3weeks apart during which the subjects used unstable shoes for regular activities. Electromyography of lower limb muscles, absolute and relative oxygen consumption, perceived exertion rating and heart rate was calculated.
RESULTS: Tibialis anterior activation varied significantly with shoe type, irrespective of grade. Soleus, vastus medialis, and biceps femoris showed activation differences in specific gait phases. There was a main effect for absolute and relative oxygen consumption, RPE and HR only with grade. Shoe type showed no effect.
CONCLUSION: Though there is no difference in overall physiological variables, but changes in electromyography in specific phases highlight possible muscle toning benefits of unstable shoes. / Graduate / 0350 / 0354 / 0382 / avneetchatha@gmail.com
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Investigations of water and tracer movement in covered and uncovered unsaturated waste rockMarcoline, Joseph R. 11 1900 (has links)
A better understanding of the hydrogeology of mine waste rock and cover systems is essential for the quantification, prediction and reduction of metals loading to the receiving environment. A series of experiments were conducted on an instrumented intermediate-scale waste rock pile at the Cluff Lake Mine in Saskatchewan to investigate the changes in flow and solute transport within coarse waste rock under three different surface conditions. Following these studies, the waste rock pile was deconstructed, structures were mapped, and samples were collected for physical characterization and pore water extraction. The internal structure of the waste rock pile was more important than the texture and topography under the free-dumped and ripped/leveled surface, while the surface condition was found to be the dominant control on spatial and temporal variability of outflow from the waste rock with the covered surface. Data from a deuterium tracer test, lysimeter outflow, and from TDR probes were used to derive estimates of the maximum and an average pore water velocity through the uncovered and the covered waste rock. An average pore water velocity through the matrix materials of the uncovered waste rock was approximately 1.5 m/yr and maximum preferential flow velocities were as high as 5 m/day. The post-cover pressure wave velocity of 0.1 to 1 m/day is inferred from outflow and TDR data, and average pore water velocities (0.39 m/y and 0.73 m/y) are calculated by the water flux and tracer methods, respectively. The distribution of the tracers in pore water and the internal structure were mapped during a detailed deconstruction of the waste rock pile and attempts were made to link the data to the spatial and temporal patterns of lysimeter outflow. The pore water chloride concentrations and the deuterium values did not provide conclusive data necessary to link the spatial and temporal patterns observed in the lysimeter hydrographs to internal structure; however, it provided insight into the internal flow mechanisms and water residence times. / Science, Faculty of / Earth, Ocean and Atmospheric Sciences, Department of / Graduate
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Thrombosis and Anticoagulation Therapy in Coronary EctasiaPerlman, P. E., Ridgeway, N. A. 01 January 1989 (has links)
A 41‐year‐old man presenting with unstable angina was found to have diffuse coronary ectasia with a partially occluding thrombus in the proximal left anterior descending artery. Anticoagulation with heparin followed by warfarin resulted in relief of angina and resolution of thrombosis at follow‐up angiography 3.5 months later. The patient remains well after three years. Nonatherosclerotic ectatic coronary arteries are prone to thrombosis possibly because of spasm, intimal damage, and blood current eddies. We believe that chronic warfarin therapy may be indicated in many patients with coronary ectasia.
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Nardilysin is a promising biomarker for the early diagnosis of acute coronary syndrome / ナルディライジンは急性冠症候群の早期診断バイオマーカーとして有望であるChen, Po-Min 23 May 2018 (has links)
京都大学 / 0048 / 新制・課程博士 / 博士(医学) / 甲第21252号 / 医博第4370号 / 新制||医||1029(附属図書館) / 京都大学大学院医学研究科医学専攻 / (主査)教授 川上 浩司, 教授 中山 健夫, 教授 小池 薫 / 学位規則第4条第1項該当 / Doctor of Medical Science / Kyoto University / DFAM
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