A new mode of operation for ionization detectors is described. The amount of ionization produced in a detector is detennined by measuring the amount of heat generated during the carrier collection process. Very high detection sensitivities, including single carrier detection, may be achieved at cryogenic temperatures. Results from an experimental device operated at T=O.3K is presented.

fatigue behavior of a vanadium microalloy steel has been studied in this research. here, microstructure constituents were considered which essentially are dependent on the heat treatment conditions. the results of high cycle fatigue tests revealed that heat treatment procedure and cooling rates have significant effects on fatigue properties. optimal heat treatment cycle of the microalloyed stee...

The paper reports on the optimization of a heater used in a Thermoluminescence glow curve apparatus. Two variants of the heater, planchet system and block system, are described. Both variants performed by a cheap material as graphite and designed following cryogenic principles, are very simple constructively, ensure minimum heat losses and require

Tool steels used in marine industries demand for the effective approach to enhance their properties. Normally, conventional heat treatment is widely increase performance of tool steels. However, this method cannot fully steel performance. On other hand, cryogenic a supplementary process treatment, which can promote conversion retained austenite martensite and accelerate precipitation fine carbi...

The design, fabrication, testing and analysis of a microchannel heat exchanger, a key component for a microminiature Joule-Thomson Cryogenic Refrigerator is described. Results show that the heat exchanger can be fabricated efficiently and economically with the existing manufacturing technology. The heat exchanger was tested to be mechanically robust and durable under high pressure operating con...

In micro-satellites, delicate instruments are compacted into a limited space. This raises concerns of active cooling and remote cooling. Silicon based micro-pump arrays are employed thanks to manufacturing simplicity, a small cryogen charge, etc, and keep the instruments within a narrow cryogenic temperature range. The pumping capacity and reliability of the micro-pump are critical in terms of ...

A theoretical and experimental parametric study of the heat-transfer phenomena on a multistage passive cryogenic radiator is presented. This investigationwas performed in the frame of a cooperative effort between Clemson University and the Federal University of Santa Catarina. Passive cryogenic radiator technology is under development at the Satellite Thermal Control Laboratory at the Federal U...

A cryogenic horizontal single loop target has been designed, built, tested and operated for the G0 experiment in Hall C at Jefferson Lab. The target cell is 20 cm long, the loop volume is 6.5 l and the target operates with the cryogenic pump fully immersed in the fluid. The target has been designed to operate at 30 Hz rotational pump speed with either liquid hydrogen or liquid deuterium. The hi...

Significant heat transfer issues associated with four alternative hydrogen storage methods are identified and discussed, with particular emphasis on technologies for vehicle applications. For compressed hydrogen storage, efficient heat transfer during compression and intercooling decreases compression work. In addition, enhanced heat transfer inside the tank during the fueling process can minim...