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A series of (74.4-x) TeO2 – (4.3) LiO2 – (21.3) LiCl – (x) Eu2O3 with 0.0 ≤ x ≤ 2.0 mol % has been made using melt-quenching technique and their optical characteristic has been studied. The present works cover the preparation of the glass sample and the effects of Eu3+ on the physical properties, absorption and photoluminescence behaviour of the lithium chloride tellurite glass. The physical properties such as density and molar volume are determined. It is found that the density and molar volume presents fluctuation trends. As the samples are excited at 393 nm, six emission peaks have been observed at 532, 552, 586, 613, 649, and 697 nm indicating the transitions of 5D1 → 7F1, 5D0 → 7F0, 5D0 → 7F1, 5D0 → 7F2, 5D0 → 7F3 and 5D0 → 7F4 respectively. It is observed that transition 5D0 → 7F2 shows the highest intensity. The emission intensity increases with the increment of Eu2O3 concentration. The high-intensity ratios of 1.88 observed for glass sample contain 2.0 mol % Eu2O3 concentrations indicate a greater degree of Eu-O-covalency and possess the better quality of host matrix.

Lightweight glass-ceramic from waste material consists of (x) paper ash- (80-x) cullet – 20 Kaolin clay where (10 ≤ x ≤ 30 weight %) are sintered at 900°C, 1000°C and 1100°C using conventional solid-state reaction technique. The influence of composition and sintering temperature on density, crystalline phase, porosity and surface pore morphology was studied. The crystal symmetry, space group and unit cell dimensions which are executed from XRD data are analyzed using SmartLab Studio II Powder XRD software. Meanwhile, the lattice parameter, cell volume, theoretical densities and porosity were estimated by Rietveld refinement method. The results reveal that all parameters exhibit a temperature-dependent character, as the temperature is increased, the density decreases and porosity increases due to bloating effects. It is also found out that the glass-ceramic compose of 25 paper ash −55 cullet-20 Kaolin clay, sintered at 900°C exhibits an optimum characteristic of the sample density reached optimum because of vitrification between cullet glass, paper ash and kaolin clay to form liquid phase which promotes adhesion and polymerization. It is observed that the surface morphology of the sample is affected by the crystallization process during sintering.

In this study, the performance of a thermoelectric cooler (TEC) as a simple and easy-to-assemble freezing instrument has been evaluated. Experiments were carried out using samples with different viscosity ranging from 44.07 to 16 965.80 MPa. The analysis of sodium component of the samples by direct laser irradiation of frozen samples showed emission enhancement and higher signal-to-noise ratio compared to that of liquids. This work also focused on using chemometrics methods such as principal component analysis (PCA) to compare the principal component score separation and clustering pattern between frozen and liquid samples. The PCA was constructed by dividing the samples into two different categories: (i) type (paste, cream, gel, and oil) and (ii) viscosity (more than and less than 10 000 MPa). The frozen samples showed a more established separation and clustering compared to that acquired from the liquid samples. However, poorer clustering pattern of some frozen samples could be due to the heat transfer during laser–sample interaction inducing surface melting and splashing. The average laser-induced breakdown spectroscopy (LIBS) spectra were taken at as many different surface areas as possible to ensure the sample surface always maintain similar freezing temperature. This work showed that the TEC pre-treatment method had improved the LIBS measurement of the liquid samples.

Laser induced breakdown spectroscopy (LIBS) is one of the analytical spectroscopy technique used in determining elemental composition of solid, liquid or gas sample using high energy laser pulse. However, LIBS technique associated with liquid sample often suffers from strong splashing and shockwave, thereby affecting the LIBS experiment repeatability and performance analysis. Therefore, a simple and quick-freeze sample pre-treatment approach using Peltier Thermoelectric Cooler (TEC) to solidify the water is applied to maintain the inherent homogeneity and chemical composition of the initial liquid sample before each LIBS analysis. This approach successfully solidified and maintained the liquid sample at its freezing point throughout the LIBS signal acquisition process. In this work, the qualitative analysis liquid samples and its solidified form, consisting of 0.5, 1.0, 1.5 and 2.0 mol/L sodium chloride (NaCl) were determined under similar experimental conditions by using LIBS. Plasmas were produced by focusing the output of Nd: YAG laser (1064nm, 6 ns and 1 Hz) on the surface of the bulk NaCl solution and its solidified form. LIBS signatures for sodium (Na) and chlorine (Cl) atomic emission lines (589.00 and 499.55 nm, respectively) were collected for estimating sodium and chlorine depositions in NaCl solutions to indicate correlation between their assay and LIBS measurements. For solidified sample, Na and Cl showed improved signal-to-noise ratio and limits of detection (47.8% and 8.8%, respectively) without the difficulties usually associated with liquid samples, demonstrating the benefits of this sample pre-treatment approach.

Laser-induced breakdown spectroscopy (LIBS) is an analytical spectroscopy technique that offers precise quantitative chemical analysis using high energy laser pulse. Although LIBS has been linked as an analytical technique with no sample preparation, this case may be a boundary in preventing it from being a more advanced technique. Regardless of LIBS countless contributions in providing measurements for solid samples, the future applications of LIBS can be explored with the aid of sample preparation methods. This review highlights the previous works of researchers that have proposed and improved various configuration methods specifically targeting to upgrade the LIBS measurements of liquid samples.

LIBS plasma produced by a 1064 nm Q-switched Nd:YAG laser in an atmospheric pressure was studied for the stainless steel sample. The laser output energy 150 mJ with pulse duration of 6 ns. The plasma emission spectrum was recorded by the LR1 Spectrometer connected to the fibre optic. The plasma temperature and electron density of each element were estimated by time-resolved spectroscopy of neutral atom and ion line emission. The plasma temperature was obtained from the Boltzmann plot method and their electron density was determined by using Saha-Boltzmann equation method. The preliminary qualitative LIBS analysis shows that several elements contained in the stainless steel. The element detected was Cu, Fe, Mn, Ni, and Cr. The results shows that Mn and Fe has the highest plasma temperature of 1.2 eV, but the electron density of Mn was the highest with value 4.6x1020 cm-3, while the Cu has the lowest temperature that is 0.73 eV with the electron density 2.8x1017 cm-3. The results are discussed.

Spectroscopic properties of Nd:YAG laser rod pumped by a new developed flashlamp is investigated. A new power supply is constructed to power xenon flashlamp. A 1 at.% Nd:YAG laser rod is transversely pumped by the flashlamp and stabilized by a water cooling system operated at ambient temperature of 20°C. The absorption and emission spectrum of the flashlamp pumped Nd:YAG rod is analyzed via spectroscopy technique. The peak absorption line is identified to be at 882 nm. The dominant emission line obtained from transition 4F3/2→4I9/2 comprised of quasi three level laser at 938.5 and 946 nm with the corresponding cross section of 2.42×10−19cm2 and 3.04×10−19cm2 respectively. This cross section is found almost ten times greater than the usual one.

The thermal stress effect on various doping levels of yttrium vanadate crystal Nd:YVO4 is investigated. Diode end-pumped source was used to obtain the input-output characteristics of the vanadate crystal. The laser performance of the low doping crystal is poor since the optical conversion efficiency is small and high threshold pump power. However the low Dopant crystal is not associated with thermal stress thus no thermal damage. Differently with higher concentration of Nd ions crystal, the laser performance is relatively high but it is accompanied with thermal damage which comprised of microcrack, microfracture and contamination. The high absorption on the doping ions with additional external impurities causes extra heat generation which leads to thermal fracture.

This paper reports the development of triggering circuits of xenon flash lamp for solid‐state laser. The method used in this study is simmer mode series triggering. The ionization started by igniting the flashlamp by using voltage pulse of 5 kV with pulse duration 3 Ps. The simmer current is flow continuously through the flash lamp just after the gaseous breakdown in the flash lamp. The output of simmer current supply in this study is about 170 V with DC current of approximately 75 mA.