Kurnia Lahna

Syiah Kuala University | UNSYIAH · Department of Physics

This study introduces a novel and simple way to suppress the self-absorption effect in laser-induced breakdown spectroscopy (LIBS) by utilizing a defocusing laser irradiation technique. For this purpose, a Nd:YAG laser with a wavelength of 1,064 nm and repetition rate of 10 Hz with energy in the range of 10 mJ—50 mJ was used. The laser irradiation...

In this work, laser induced breakdown spectroscopy (LIBS) analysis of the soil samples collected from Aceh, a place in Indonesia worst affected by 2004 Indian Ocean tsunami. In the LIBS experimental system, a high energy pulsed laser beam was focused on the tsunami affected soil samples and the atomic emission lines, originating from the laser indu...

This study introduces a novel and extremely simple way for suppressing the self-absorption effect in laser-induced breakdown spectroscopy (LIBS) by utilizing a defocusing laser irradiation technique. It is claimed that defocusing laser irradiation produces more uniform laser plasma due to lower fluence than tight focus laser irradiation, hence grea...

The development of science and technology has influenced the pattern of human life, especially the housing as the basic needs in human life. This can also be seen in the Acehnese people who have made changes to their traditional houses which will unwittingly have an impact on the thermal performance of the building.. This study observes the thermal...

Preliminary optical spectroscopy studies have been carried out on betel nut samples using a new analytical tool, LIBS. The LIBS system consists of an neodymium -doped yttrium aluminium garnet (Nd YAG) laser as an excitation source, laser beam conditioning equipment, and an optical multichannel analyzer system (OMA system). Betel nut samples were co...

A new approach to allow detection of Cl emission using atransversely excited atmosphere (TEA) carbon dioxide (CO 2 ) laser-induced breakdown spectroscopy (LIBS), namely utilization of a metal sub-target, was introduced. The Cl sample was prepared from pure chemical powder in the form of a solutiondeposited on the metal sub-target. A zinc selenium l...

Cocoa seeds well known contains many antioxidant, thus it is really useful to human health. The elemental content of cocoa (Theobroma cacao L.) was examined using LIBS. The Cocoa seed was collected from Pidie Jaya Regency in the special autonomy region of Aceh, Indonesia. The examination was carried out is using LIBS using an Nd-YAG laser (Q-Smart...

A study was conducted for identification of heavy metal pollution from biological sample as a potential proxy of environmental pollution due to industrial waste. The identification was conducted using the emerging analytical tool, namely laser induced breakdown spectroscopy (LIBS). The sample was collected from seawater near a cement plant in Aceh....

Laser induced breakdown is a highly temporally and spatially dynamic phenomenon, normally studied using a highly temporally resolved optical detector system. In this work, a compact, low cost optical multichannel analyzer (OMA) system without a built-in temporal gating device and thus operated under a free running mode was used to investigate the c...

Self-absorption, which is known to severely disturb identification of the emission peak intensity in emission-based spectroscopy, was first studied using ordinary single pulse laser-induced breakdown spectroscopy (LIBS). It was found that severe self-absorption, with an evident self-reversal, occurs in the resonance emission lines of high concentra...

A series of experiments are conducted for the study of time-dependent variations of major emission from the metastable excited He generated in various experimental conditions. Different Nd:YAG laser pulse widths and pulse energies, as well as purity of the He gas, are employed for studying quenching effects including the use of a Cu target in an ex...

Temperature of plasma generated by CO 2 laser from soil sample prepared by the two different methods, namely metal mesh, and silicone grease methods, was examined. The plasma was produced by focusing the laser beam on the sample at 1 atmospheric pressure. The plasma characteristics namely temperature was estimated by the Boltzmann plot method. The...

Quick qualitative elemental analysis of agriculture soil has been made using a pulsed CO 2 LIBS. The laser beam with different pulse energy was focused on agriculture soil sample under ambient of helium at atmospheric pressure (760 Torr) after the laser beam passes through a covering metal mesh. Emission spectra from the consequent plasma was recor...

Detection of chlorine (Cl) using LIBS technique is greatly influenced by experimental conditions including the delay time of the detecting device. Time evolution of Cl emission in plasma produced on polyvinyl chloride (PVC) sample using CO 2 laser with variation of delay time has been carried out. The plasma was produced at atmospheric pressure und...

Chlorine (Cl) detection using laser induced breakdown spectroscopy (LIBS) techniques in geology and environment samples is still challenging since the experimental conditions greatly influence the analytical performance of LIBS. Cl emission in LIBS must be studied carefully to find the optimum condition to allow Cl detection. In the present study,...

This study is aimed at elucidating the physical processes responsible for the excellent spectral qualities in terms of full width at half maximum (FWHM) and signal to noise (S/N) ratio shown in a special double pulse laser induced spectroscopy. A part from the use of atmospheric He ambient gas, the achievement is due to the first laser for generati...

We report the results of an experimental study of food analysis using Nd:YAG nanosecond (ns) laser at various pulse energies in atmospheric ambient air and He ambient gas at different pressures. In contrary to previous results indicating the unfavorable applications of LIBS to food analysis using lower pulse energies and atmospheric ambient air, th...

The physical characteristic in term of temperature and electron density of the laser-induced plasma produced on a river shell sample has been investigated. The plasma was produced by an Nd: YAG laser beam (1064 nm) at low pressure (5 Torr) of air surrounding gas. Multi-elemental panoramic line spectra (200-900 nm) have been analysed at different de...

One of the methods in assessing the quality of gemstones is by observing the degree of scattering of visible light inside or on the surface of the gemstones. This scattering phenomenon is determined by its optical characteristic and its stoichiometric compounds. In this study we analyze the internal scattering of red 633 nm HeNe laser light in seve...

Luminescence is an optical characteristic of materials under optical illumination. We have studied the luminescence of gemstone samples of nephrite which are common in Aceh. The samples were illuminated using two laser beam, green laser at 543 nm and red laser at 633nm.The transmitted and scattered light from samples were then resolved using a pris...

Temperature as one very important characteristics of a laser-induced plasma was estimated using many calcium emission spectral lines. This was possible due to the availability of a wide coverage and high resolution optical multichannel analyser (OMA) system allowing a simultaneous detection of many emission spectral lines from one element. The plas...

A wide coverage spectral investigation on the muscle of river calm sample has been carried out using laser-induced breakdown spectroscopy for examining the overall profile of the emission spectra from the produced plasma. The basic apparatus of LIBS system used is a Nd-YAG laser and wide coverage optical multichannel analyzer (OMA) system. The rive...

We report the experimental evidence of shock wave plasma generation by direct observation of the plasma propagation using 68 mJ 1064 nm Nd-doped yttrium aluminum garnet laser irradiation on a relatively soft organic sample in He ambient gas at 2 kPa. The density jump associated with the arrival of the plasma front at a certain position is detected...

An experimental study is performed on the time-dependent intensity variations of Zn emission focusing on the triplet (Zn I 481.0 nm) and singlet (Zn I 636.2 nm) emission lines induced under three experimental conditions. A single nanosecond (ns) Nd:YAG laser in standard laser-induced breakdown spectroscopy (LIBS) setup is employed for the investiga...

In this work, LIBS technique has been used for detection of heavy metal especially iron, Fe in soil sample. As there are a large number of emission spectral lines due to Fe and other constituents in soil, this study is intended to identify emission spectral lines of Fe and finally to find best fit emission spectral lines for carrying out a qualitat...

This report presents the results of laser-induced breakdown spectroscopy (LIBS) study on biological and food samples of high water content using a picosecond (ps) laser at low output energy of 10 mJ and low-pressure helium ambient gas at 2 kPa. Evidence of excellent emission spectra of various analyte elements with very low background is demonstrat...

An experimental study is performed on the comparative advantages of nanosecond (ns) and picosecond (ps) lasers in laser-induced breakdown spectroscopy (LIBS) analysis. The experiment focused on the relative efficiencies of the plasma emission induced by the two lasers in low-pressure Ar ambient gas for samples of various hardnesses. It is shown tha...

An experimental study is conducted on the possibility and viability of performing hardnessmeasurement of the various stone and chert samples in low pressure (600 Pa) CO2 ambient gas, a condition that is encountered in the Mars atmosphere. For this study, a nanosecond Nd-YAG laser is employed to generate plasma emission from the samples with differe...

An experimental study has been performed to examine the physical characteristics of pharmaceutical products, such as tablet, by employing an emission plasma induced by Nd-YAG laser at a low pressure of Helium gas. The hardness of tablet is one of the parameters that examined during the production process for standard quality of pharmaceutical produ...

Presented in this paper are the results of an experimental study on the laser induced plasma emission of a number of CN free samples (urea, sucrose) with 40 mJ pulse energy using He and N₂ ambient gases. It is shown that the CN emission has its exclusive sources in the molecules produced as the result of chemical bonding either between t...

We have conducted an experimental study exploring the possible application of laser-induced breakdown spectroscopy (LIBS) for practical and highly sensitive detection of metal impurities in water. The spectrochemical measurements were carried out by means of a 355 nm Nd-YAG laser within N₂ and He gas at atmospheric pressures as high as 2...

We report in this paper the results of an experimental study on the spectral and dynamical characteristics of plasma emission induced by 1 mJ picoseconds (ps) Nd-YAG laser using spatially resolved imaging and time resolved measurement of the emission intensities of copper sample. This study has provided the experimental evidence concerning the dyna...

We report the results of experimental study on CN 388.3 nm and C I 247.8 nm emission characteristics using 40 mJ laser irradiation with He and N2 ambient gases. The results obtained with N2 ambient gas show undesirable interference effect between the native CN emission and the emission of CN molecules arising from the recombination of native C abla...

An experimental study was conducted on the spatial distributions of hydrogen emission intensities from low-pressure plasmas generated by laser ablation of zircaloy-4 and black stone targets in nitrogen and helium ambient gases. In addition to confirming the previously observed intensity enhancement effect in ambient helium gas, the hydrogen and hel...

A series of measurements have been performed on the time dependences of the intensities of helium, hydrogen, and deuterium emission lines from the corresponding laser-induced helium plasma at atmospheric pressure for two different He flow rates. The prolonged H _α and H _β emissions along with their constant intensity ratio over...

A special interferometric technique with high sensitivity has been devised on the basis of rainbow refractometry without the use of an additional and delicate amplitude-splitting setup. This new technique was used for the characterization of shock wave plasma induced by a Q-switched Nd:YAG laser on various metal samples under reduced surrounding ga...

Abstract : A special interferometrik technique with high sensitivity has been devised on the basis of rainbows refractometry without the use of an additional and delicate amplitude-splitting setup. This new technique was use for the characterization of shock wave plasma induced by a Q-sw Nd-YAG laser on various kind of metal samples under reduced g...