نتایج جستجو برای: cryogenic cooling
تعداد نتایج: 61274 فیلتر نتایج به سال:
The NICMOS detectors are sensitive to the operating temperature. During the Cycle 7 era, NICMOS was cooled through cryogenic solid nitrogen. This resulted in an operating temperature varying from 61K to 62.5K before the nitrogen was exhausted. Using the new NICMOS Cooling System (NCS), the nominal temperature is significantly more stable, but at a higher temperature, 77.15 K. The stability of t...
Due to their large optical phonon energies, nitride semiconductors are promising for the development of terahertz quantum cascade lasers with dramatically improved high-temperature performance relative to existing GaAs devices. Here, we present a rigorous Monte Carlo study of carrier dynamics in two structures based on the same design scheme for emission at 2 THz, consisting of GaN /AlGaN or Ga...
We demonstrate the mixing of rotational states in the ground electronic state using microwave radiation to enhance optical cycling in the molecule yttrium (II) monoxide (YO). This mixing technique is used in conjunction with a frequency modulated and chirped continuous wave laser to slow longitudinally a cryogenic buffer-gas beam of YO. We generate a flux of YO below 10 m/s, directly loadable i...
K. Żak, W. Grzesik, M. Prażmowski, Opole University of Technology, Department of Manufacturing Engineering and Automation, Opole, Poland This paper presents a sequential machining process which incorporates CBN hard turning with cryogenic pre-cooling of the workpiece (CHT) and ball burnishing (BB). The main goal of this study was to select machining conditions enhancing the quality of parts mac...
The response of a distributed temperature sensor based on coherent Rayleigh scattering is experimentally studied in the temperature range from 77 K up to 300 K, using fibres with standard and ORMOCER coating. A precise and absolute frequency scan is performed to obtain the best temperature resolution that turns out to be in the mK range. Experimental results point out that heating and cooling p...
Cold and dense samples of naphthalene (C(10)H(8)) are produced using buffer gas cooling in combination with rapid, high flow molecule injection. The observed naphthalene density is n approximately 10(11) cm(-3) over a volume of a few cm(3) at a temperature of 6 K. We observe naphthalene-naphthalene collisions through two-body loss of naphthalene with a loss cross section of sigma(N-N) = 1.4 x 1...
In recent years, hard turning has been found to be a well-known substitute for traditional grinding acquiring the finish quality of hardened steel without sacrificing productivity. There are many issues that should carefully understood and dealt with attain efficacious performance in turning. This article discusses modern manufacturing challenges focus on analyzing current state art process ter...
The aim of this paper is to focus on the effect of cryogenic treatment on the microstructure, mechanical and wear properties of Al 6061 and Al 8011. The first objective was to understand the degree to which hardness of these aluminium grades have been enhanced by giving cryogenic on the specimens. The second objective is to check the wear resistance property of these two aluminium specimens i...
A cryogenically cooled in-vacuum undulator was installed in the ID6 test beamline of the ESRF in January 2008. This 2 metre long hybrid undulator has a period of 18 mm. The magnetic assembly is based on NdFeB permanent magnets cooled at a temperature close to 150 K. A liquid nitrogen closed loop is used for the cooling of the undulator. This cooling system is well adapted to achieve a uniform t...
نمودار تعداد نتایج جستجو در هر سال
با کلیک روی نمودار نتایج را به سال انتشار فیلتر کنید