[en] A theoretical analysis of transient fluid flow and heat transfer in a triangular micro heat pipes (MHP) has been conducted to study the thermal response characteristics. By introducing the system identification theory, the quantitative evaluation of the MHP's transient thermal performance is realized. The results indicate that the evaporation and condensation processes are both extended into the adiabatic section. During the start-up process, the capillary radius along axial direction of MHP decreases drastically while the liquid velocity increases quickly at the early transient stage and an approximately linear decrease in wall temperature arises along the axial direction. The MHP behaves as a first-order LTI control system with the constant input power as the 'step input' and the evaporator wall temperature as the 'output'. Two corresponding evaluation criteria derived from the control theory, time constant and temperature constant, are able to quantitatively evaluate the thermal response speed and temperature level of MHP under start-up, which show that a larger triangular groove's hydraulic diameter within 0.18–0.42 mm is able to accelerate the start-up and decrease the start-up temperature level of MHP. Additionally, the MHP starts up fastest using the fluid of ethanol and most slowly using the working fluid of methanol, and the start-up temperature reaches maximum level for acetone and minimum level for the methanol. -- Highlights: • Transient thermal response of micro heat pipe is simulated by an improved model. • Control theory is introduced to quantify the thermal response of micro heat pipe. • Evaluation criteria are proposed to represent thermal response of micro heat pipe. • Effects of groove dimensions and working fluids on start-up of micro heat pipe are evaluated

[en] Electronic stopping powers for 80-350 keV ¹⁹F ions in AgGaS₂ were obtained by range measurement. Depth profiles of ¹⁹F in AgGaS₂ were measured by using the ¹⁹F(p,αγ)¹⁶O resonant nuclear reaction at E_R=872.1 keV. A proper convolution calculation method was used to extract the true distribution of fluorine from the experimental excitation yield curves. The electronic stopping powers were derived through fitting the projected range distributions, simulated by using the TRIM/XLL code, to the experimentally measured range distributions. The electronic stopping cross sections were compared with those obtained from Monte Carlo simulation codes

[en] Range distributions for fluorine ions implanted in AgGaS₂ in an energy range of 80-350 keV were measured by using the ¹⁹F(p,αγ)¹⁶O resonant nuclear reaction at E_R=872.1 keV, with width Γ=4.2 keV. A proper convolution calculation method was used to extract the true distributions of fluorine from the experimental excitation yield curves. The range distribution parameters, R_p and ΔR_p, were obtained and compared with those obtained from different Monte Carlo simulation computer codes

[en] Optical emission spectra of the plasma produced by 1.06 μm Nd:YAG laser irradiation of a potassium titanium phosphate (KTP) crystal in vacuum and in air were recorded and analyzed in a spatially resolved manner. Electron temperatures and densities in the plasma in vacuum were determined with the Boltzmann plot method using five Ti(II) emission lines and the Stark-broadened linewidths of neutral K atoms, respectively. The dependence of the electron densities and temperatures on distance from the target surface and on laser irradiance were manifested. In order to see the effect of backing gas, we also performed laser ablation of a KTP crystal in air and compared the results with that of the ablation in vacuum. Gas dynamical parameters of the laser-induced KTP evaporation wave were simulated using a hydrocode developed in our group based on the self-similar solutions of the gas dynamical equations. Moreover, the velocity of the evaporating wave and the vapor pressure were calculated under different laser power densities

[en] Electronic stopping powers for 80-350 keV ¹⁹F ions in KTiOAsO₄ (KTA) were obtained by range measurement. Depth profiles of ¹⁹F in KTA were measured by using the ¹⁹F(p, αγ)¹⁶O resonant nuclear reaction at E_R=872.1 keV, with width Γ=4.2 keV. A proper convolution calculation method was used to extract the true distributions of fluorine from the experimental excitation yield curves. The electronic stopping powers were derived through fitting the projected range distributions, simulated by using the TRIM/XLL code, to the experimentally measured range distributions. The electronic stopping cross sections were compared with those obtained from Monte Carlo simulation codes

[en] Electronic stopping powers for 80-350 keV ¹⁹F ions in AgGaSe₂ were obtained by range measurement. Depth profiles of ¹⁹F in AgGaSe₂ were measured by using the ¹⁹F(p,αγ)¹⁶O resonant nuclear reaction at E_R=872.1 keV. A proper convolution calculation method was used to extract the true distribution of fluorine from the experimental excitation yield curves. The electronic stopping powers were derived through fitting the projected range distributions, simulated by using the TRIM/XLL code, to the experimentally measured range distributions. The electronic stopping cross-sections were compared with those obtained from Monte Carlo simulation codes

[en] Short communication

[en] The formation enthalpy, the excess entropy and excess Gibbs free energy of Pu-Am, Pu-Ce and Pu-Al binary alloy were calculated by the use of the semiempirical Miedema model. The obtained thermodynamic data were used to calculate the activity of the three Pu-based alloys. The results indicated that the formation enthalpythe of Pu-Am, Pu-Ce and Pu-Al binary melts show negative deviation from ideal solution, in which Pu-Al binary melt is more inclined to form intermetallic compounds than Pu-Am and Pu-Ce binary melts because of the strong interaction between Pu and Al atoms. The results are in agreement with experimental phase diagram. (authors)

[en] A thin layer of sputtered SiO₂ film was deposited on AlGaAs/AlGaInAs multiple quantum well (MQW) samples and a subsequent rapid thermal annealing (RTA) was carried out. Photoluminescence (PL) studies showed a 60 meV band-gap shift for the AlGaAs/AlGaInAs MQW. An interdiffusion length of 10.7 Angst corresponding to the above band-gap shift in the MQW was obtained using transfer matrix method (TMM). An apparent diffusion coefficient was evaluated to be 1.43x10^-16 cm²/s. We also calculated the energy levels of the AlGaAs/GaAs MQW with four single wells using TMM and compared the calculated results with the experimental values from the PL measurements. The comparison shows good agreement. To see the influence of RTA condition on PL characteristics of the wells at different depth beneath the surface of the sample, we annealed the SiO₂ film covered AlGaAs/GaAs MQW at 650-780 deg. C for 20-80 s. A subsequent PL measurement shows that the photoluminescence characteristics of the four single quantum wells behave differently with the change of RTA condition. The PL intensities of the wells close to the surface and the bottom of the AlGaAs/GaAs MQW are sensitive to the RTA condition while those of the wells in the middle of the MQW show little variations with the change of RTA conditions

[en] This paper describes the methods of shunt impedance measurements according to Slater's perturbation theorem on the Hefei Synchro Radiation Accelerating Cavity (HFSRAC). The results are compared to the computer calculated shunt impedance. The performances are also evaluated initially. The experiments show that the design and dimensions of the HFSRAC are reasonable