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Laser-induced breakdown spectroscopy (LIBS) has been recognized as a promising technique for analyzing sensitive nuclear materials such as uranium, plutonium, and curium in a high-radiation environment, especially since the implementation of IAEA (International Atomic Energy Agency) safeguards. The uranium spectra of ore samples were quantitatively analyzed prior to analyzing sensitive materials in the nuclear industry. The purpose of this experiment is to extract quantitative information about the uranium in a uranium ore using a standard addition approach. The uranium ore samples containing different concentrations of U were prepared by mixing raw ore powder with natural uranium oxide powders. Calibration sets of 0.2, 0.4, 0.6, 0.8 and 1.0 wt.% uranium concentrations within the uranium ore sample were achieved. A pulsed and Q-switched Nd:YAG laser at a wavelength of 532 nm was used as a light source. An echelle spectrometer that covers a 190–420 nm wavelength range is used to generate a calibration curve and determine the detection limit of uranium in the ore matrix. The neutral atomic-emission peak at a wavelength of 356.659 nm indicated a detection limit of ~ 158 ppm for uranium, and the uranium concentration was determined in a raw ore sample that has an unknown quantity of uranium.

The microwave dielectric properties of Ca(0.85)Nd(0.1)TiO(3) - LnAlO(3) (Ln = Sm, Gd, Dy, Er) ceramics are investigated in this paper. The structural characteristics of the specimens were evaluated by Rietveld refinement of Xray diffraction (XRD) patterns and high-resolution transmission electron microscopy (HRTEM). Solid solution limits were dependent on the ionic radius of Ln(3+) ions. With the decrease of the ionic radius of the Ln(3+) ions, the thermal stability of the resonant frequency decreases. This can be attributed to the increased level of oxygen octahedral distortion caused by the increase in the B-site bond valence in the ABO(3) perovskite structure. The dielectric constant (K) and the quality factor (Qf) of the specimens were dependent on the polarizability and grain size, respectively.

Surface of a stainless steel has been modified by atmospheric-pressure plasma jet method at room temperature. The impulse voltage is applied to ignite a plasma discharge using high purity (99.999%) reactive gases: N 2 and O 2 . The treated stainless steel is characterized by the activation property of the surface using a contact angle analyzer. Surface energy for the treated stainless steel is increased remarkably when compared to the untreated surface. From the results of X-ray photoelectron spectroscopy and atomic force microscopy, we could confirm that the main functional groups, causing the change in hydrophilic surface were generated under the surface reactions caused by reactive etching and oxidation of ions and activated species in the plasma. In addition, the aging effect during the duration of the hydrophilic property is also studied to investigate the production cost for the industrial applications.

A study of combustion synthesis of diamond films has been carried out using low-pressure, fuel-rich hydrocarbon/oxygen flames. Diamond growth results are reported for acetylene/oxygen, propylene/oxygen, and propane/oxygen flames. The best results are achieved with acetylene/oxygen flames, in which we have grown uniform, 5-cm-diameter polycrystalline films at up to 2.3 μm/h. The deposition rate in propane/oxygen is much lower (0.15 μm/h), and the diamond film quality is also lower. The experimental results are compared to the predictions of a numerical model that includes both detailed flame chemistry and simplified diamond surface chemistry. The comparison of the experimental conditions with the simulation results shows that diamond growth occurs for stoichiometries where a small amount of hydrocarbon ( The model correctly predicts the variation of film growth rate with changes in pressure, substrate temperature, and fuel type. For all flames, the absolute predicted growth rate is somewhat higher than measured, but the agreement is reasonable considering the modeling uncertainties associated with the high peak flame temperatures and incompletely understood diamond surface kinetics.

Microwave dielectric properties of Ca0.85Nd0.1TiO3- LnAlO3(Ln = Sm, Gd, Dy, Er) ceramics have been investigated. Structural characteristics of the specimens were evaluated by Retieveld refinement of XRD patterns and HRTEM. Solid solution limits were dependent on the ionic radius of Ln3+ ion. With the decrease of ionic radius of Ln3+ ions, the thermal stability of the resonant frequency (TCF) was decreased which could be attributed to the increase of oxygen octahedral distortion by the increase of B-site bond valence. The dielectric constant (K) and the quality factor (Qf) of the specimens were dependent on the polarizability and grain size.

Al/sub 2/O/sub 3/ (EOT=22.7 /spl Aring/) gate dielectric layer formed by Atomic Layer Deposition (ALD) process have been characterized for sub-100 nm CMOS devices. The gate leakage current was 3 orders of magnitude lower than that of SiO/sub 2/ and the hysteresis of C-V curve was not observed. However, the negative fixed charge induced the flat band voltage (Vfb) shift and degraded the channel mobility of MOS transistor. The Vfb shift was reduced and channel mobility was improved by applying P+ gate by BF/sub 2/ implantation. It is suggested that the phosphorous diffused from gate polysilicon has a role of network modifier in Al/sub 2/O/sub 3/ film and formation of the Al-O- dangling bond which may be ascribed to negative fixed charge.