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New structures and new gas fillings have extended the domains of applications of multiwire chambers. They can be used for the detection and imaging of UV light, X-rays, γ-rays in the energy range useful for nuclear medicine.  相似文献   
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An experiment to study high energy γ rays from localized cosmic sources is described. A number of Al mirrors reflects the Cherenkov light emitted by the showers into photosensitive gas chambers on the mirror focal plane. The use of gas chambers with large active areas allows a sensitivity superior to existing experiments to be reached. Pad readout gives the required angular accuracy. The chamber is sensitive to the middle ultraviolet Cherenkov light produced by the showers in the atmosphere. Since the ozone in the upper atmosphere absorbs the direct ultraviolet light from any outer source, the lower level atmosphere provides a large dark volume in which the Cherenkov radiation from the showers can be isolated.  相似文献   
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Four coherent betatron oscillation modes induced by the beam-beam interaction we observed in the TRISTAN Main Ring (MR) during two e+ and two e bunches colliding operation. These modes are extracted using a phase mixing technique and used for measuring beam-beam parameters. The luminosity, the coupling coefficient and the emittance are estimated from the observation. The emittance agrees with the expected value to within 15% accuracy.  相似文献   
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《Acta Metallurgica》1986,34(11):2129-2137
Samples of Pd77.5Cu6Si16.5glass, both produced in a drop tube by cooling the melt at 1700 K/s and by directional solidification with a cooling rate of 221 K/s were heated in a differential scanning calorimeter to determine the crystallization kinetics. Optical microscopy of partially devitrified samples shows that the crystallization proceeds similarly in the both samples by growth of spherical regions in the interior. A modified Kissinger analysis is used to obtain the activation energy for crystal growth (411 KJ/mol). An expression for the steady state homogeneous nucleation frequency was calculated and its applicability was verified by annealing. Constant differences (5 · 1012 and 4 · 1011 nuclei/m3 for the drop tube produced spheres and the ds samples respectively) was observed to prevail between the calculated homogeneous density of nuclei and that estimated from micrographs, suggesting heterogeneous nucleation.  相似文献   
6.
《Energy and Buildings》2004,36(8):855-863
The EnergyPlus building energy simulation software has been tested using the IEA HVAC BESTEST E100–E200 series of tests. The volume 1 final report for the International Energy Agency (IEA) solar heating and cooling programme task 22 building energy simulation test and diagnostic method for heating, ventilating, and air conditioning equipment models (HVAC BESTEST) was recently published in January 2002. HVAC BESTEST is a series of steady-state tests for a single-zone DX cooling system. Cases range from dry to wet coil, low to high part load, and low to high temperatures. This published test suite includes three sets of analytical solutions and results from several other simulation programs for comparison.This test suite was initially used to test EnergyPlus beginning with beta versions prior to its official public release, and it is also applied as an ongoing quality assurance test. The application of these tests proved to be very useful in several ways:
  • •revealed input model shortcomings, which resulted in new user inputs being added;
  • •revealed reporting errors which were fixed;
  • •revealed algorithmic errors which were fixed;
  • •revealed algorithmic shortcomings which were improved or eliminated through the use of more rigorous calculations for certain components;
  • •in later versions, caught newly introduced bugs before public release of updates.
Overall, the application of this test suite has been extremely useful in debugging and verifying the DX cooling algorithms in EnergyPlus. This paper summarizes the difficulties encountered and the benefits gained in applying the tests.  相似文献   
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For the period September 1984 to November 1985 water samples from the aquatic system of Ioannina basin were analyzed every second month for organochlorine and triazines pesticides. The detected compounds were found to follow a seasonal pattern, with an increment during summer followed by a decrease during winter and an increase again during late spring. This pattern was apparent for Ioannina lake as well as for the Kalamas river connected to it through the Lapsista's canal and tunnel. The results are discussed in terms of the amounts of the detected pesticides used for farming in the vicinity of the Ioannina basin and the seasonal rainfall.  相似文献   
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Neutron emission spectroscopy (NES) diagnosis of high-power fusion plasma has been performed with the magnetic proton recoil (MPR) spectrometer installed at the Joint European Torus tokamak. The MPR is a high performance instrument where the setting of working points to prescribed calibration values is essential. This includes the MPR focal plane detector whose photomultipliers must be monitored for gain stability with respect to short- and long-term drifts as well as transient changes. A special monitoring system was developed for the MPR including a light pulser in the form of light emitting diodes. The monitoring system as part of the MPR focal plane detector is described here as well as the monitoring procedures and applications. Results from the use of the monitoring system are presented illustrating its present capabilities and possibilities for further developments in next step NES diagnostics.  相似文献   
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《Scripta Metallurgica》1975,9(7):753-755
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