We present results from cryogenic tests of volume-phase holographic (VPH) gratings at approximately 100 K. The aims of these tests are to see whether the diffraction efficiency as a function of wavelength is significantly different at a low temperature from that at room temperature and to see how the performance of a VPH grating is affected by a number of thermal cycles. We have completed ten c...

We present results from cryogenic tests of Volume-Phase Holographic (VPH) gratings at ∼ 100 K. The aims of these tests are to see whether the diffraction efficiency as a function of wavelength is significantly different at a low temperature from that at room temperature and to see how the performance of a VPH grating is affected by a number of thermal cycles. We have completed 10 cycles between...

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 ...

We present results from cryogenic tests of Volume-Phase Holographic (VPH) gratings at ∼ 100 K. The aims of these tests are to see whether the diffraction efficiency as a function of wavelength is significantly different at a low temperature from that at room temperature and to see how the performance of a VPH grating is affected by a number of thermal cycles. We have completed 10 cycles between...

Deep cryogenic heat treatment is assumed as a supplementary heat treatment performed on steels before the final tempering treatment to enhance the wear resistance and hardness of the steels. In this study, the effects of the deep cryogenic heat treatment on the wear behavior and corrosion resistance of the 1.2080 tool steel were studied using the wear testing machine and polarization and impeda...

C3MR, MFC, and DMR processes in an integrated LNG-NGL-NRU structure are investigated using the conventional and advanced exergy and exergoeconomic analyses. The results of advanced exergy analysis reveal that in most of the equipment, the highest amount of irreversibility is occurred because of endogenous exergy destruction. In C3MR process, compressor C5 with 9730 kW; in MFC process, compresso...

17-4ph stainless steel is a martensitic precipitation hardening stainless steel that provides an outstandingcombination of high strength, good corrosion resistance, good mechanical properties, good toughness in both base metal and welds, and short time, low-temperature heat treatments that minimize warpage and scaling. this valuable alloy is widely used in the aerospace, nuclear, chemical, petr...

deep cryogenic heat treatment is assumed as a supplementary heat treatment performed on steels before the finaltempering treatment to enhance the wear resistance and hardness of the steels. in this study, the effects of thedeep cryogenic heat treatment on the wear behavior and corrosion resistance of the 1.2080 tool steel were studiedusing the wear testing machine and polarization and impedance...