Ali Khumaeni
Department Of Physics, Faculty Of Science And Mathematics, Diponegoro University, Jl. Prof. Soedarto SH, Tembalang, Semarang 50275, Indonesia

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Journal : Journal of Physics and Its Applications

Rapid Detection Of Heavy Metals On Waste-Water Polluted Soils Using Laser Induced Breakdown Spectroscopy Heri Sugito; Ali Khumaeni; Qidir Maulana Binu Soesanto
Journal of Physics and Its Applications Vol 2, No 2 (2020): May 2020
Publisher : Diponegoro University Semarang Indonesia

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.14710/jpa.v2i2.7520

Abstract

The Laser Induced Breakdown Spectroscopy (LIBS) method was successfully used to detect heavy metal elements in the soil polluted by wastewater from paper mills. The study was conducted using a Nd: YAG pulse laser with a wavelength of 532 nm at 83 mJ energy and 5 torr air pressure. The laser is fired at a soil sample that has been made in the form of pellets to produce plasma. The plasma emission spectrum formed is then detected by multichannel analyzer (OMA) to obtain the emission line spectrum that represents the content of atoms and molecules in the soil sample. The spectrum detected by OMA is then compared to the standard reference spectrum at NIST (National Institute of Standards and Technology) to find out the contents of an element on a contaminated soil sample. several types of heavy metal elements Fe, Cr, Cu, Al, Cd and Mn in soils contaminated by wastewater were detected using LIBS method. Based on research results, the LIBS method is very well used for the detection of heavy metal content in polluted soils.
Generation of monocycle efficient terahertz pulses by optical rectification in LiNBO3 at 800 nm Ali Khumaeni; Hideaki Kitahara,; Takashi Furuya; Kohji Yamamoto; Masahiko Tani
Journal of Physics and Its Applications Vol 1, No 1 (2018): November 2018
Publisher : Diponegoro University Semarang Indonesia

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.14710/jpa.v1i1.3912

Abstract

Generation of efficient terahertz (THz) pulses was experimentally made by tilted pump pulse front scheme with a Mg-doped LiNbO3 crystal. In this study, a spitfire laser (Ti:sapphire laser, 800 nm, 3 mJ, 1 kHz) was used as an optical source for the generation and detection of THz pulses. The electro-optic (EO) detection optics consisting of a ZnTe crystal (1 mm in thickness) and a balanced photodetector was used. To obtain optimum THz characteristics and pump to THz power conversion efficiency, the image of the grating was made coincides with the tilted pump pulse front. The maximum THz electric field of 8.5 kV/cm and the frequency bandwidth of 2.5 THz were achieved by using pump pulse energy of 2.4 mJ and pump pulse width of 100 fs. The THz energy of 4.15 μJ was obtained and pump-to-THz conversion efficiency was estimated to be approximately 1.73 x 10-3.
Calculation of Absorption Dose Value using MIRD Method with Cobalt 57 MIBI for Four Body Organs Asep Yoyo Wardaya; Wahyu Setia Budi; Ali Khumaeni; Chorirul Anam; Gani Gunawan
Journal of Physics and Its Applications Vol 2, No 1 (2019): November 2019
Publisher : Diponegoro University Semarang Indonesia

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.14710/jpa.v2i1.6180

Abstract

MIRD has developed methods, assumptions, models, and mathematical formulae for estimating internal radiation doses from the injected radiopharmaceuticals into the body. This study aims to determine the radiopharmaceutical distribution of Cobalt 57 MIBI in patients identified as having breast cancer by using an oncology examination with MIRD method on 4 patient's organs with some time variations. The four organs of the patient's body are the heart, thyroid, kidney, and liver. The MIRD method developed to calculate the absorption dose of each organ is the product of the cumulative activity and the S factor of each organ studied. The results showed that the highest uptake dose in these patients was in the thyroid and kidney organs, and then followed by the heart and liver. These results indicate that the thyroid and kidney organs are the most vulnerable organs by the method of injecting radiopharmaceutical doses into the body of breast cancer patients.
Characteristics of colloid silver solution based on changes in concentration and electric field using electrooptic equipment Heri Sugito; Ketut Sofjan Firdausi; Ali Khumaeni; Syifa Azahra
Journal of Physics and Its Applications Vol 4, No 1 (2021): November 2021
Publisher : Diponegoro University Semarang Indonesia

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.14710/jpa.v4i1.12419

Abstract

Research on the characteristics of colloidal silver solutions based on changes in concentration and electric field using electrooptic devices has been carried out. The purposes of this study was to determine the characteristic of colloidal silver solution based on variations in concentration and electrooptic effects. Electrooptics work based on changes in the polarization angle of the sample. The sample used is a colloidal silver solution with various concentrations. The colloidal silver solution was obtained by laser ablation method and then dissolved in aquabidest. The light source used is a laser pointer with = 532 nm. The electric field applied to the sample is 0-9 kV. The results showed that colloidal silver solution at an angle of 0º showed active plasmon resonance at the peak of polarization with concentrations of 1.9 ppm, 2.28 ppm, and 3.8 ppm. An angle of 90º also shows active plasmon resonance at the peak of polarization with a concentration of 3.8 ppm. From the results, it can be concluded that the characteristics of colloidal silver solution on change in the polarization angle due to an electric field show non-linier properties with increasing concentration.
Comparison of I-V Curves Between the Experiment of Corona Discharge on Gradient Line-To-Plane (GL-P) Configuration and The Mathematical Approach Susilo Hadi; Asep Yoyo Wardaya; Zaenul Muhlisin; Jatmiko Endro Suseno; Pandji Triadyaksa; Ali Khumaeni; Muhammad Nur
Journal of Physics and Its Applications Vol 3, No 2 (2021): May 2021
Publisher : Diponegoro University Semarang Indonesia

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.14710/jpa.v3i2.10491

Abstract

Research has been conducted on the comparison of the I-V characteristic curve between mathematical study and experiment of the generation of negative DC corona discharge in the Gradient Line-to-Plane (GL-P) electrode configuration. The reason for this research is to calculate the suitability of the corona discharge electrical current between the mathematical and experimental study. The active electrode used has length 2 cm and height 4 cm. This research is conducted with variations in the sharpness angle of the active electrode (θ) 300, 450, and 600 and variations in the distance between the electrodes () 2 cm, 3 cm, and 4 cm. The mathematical formulation of the value of the corona discharge electrical current in the configuration of the GL-P electrode is obtained by using the geometric concept approach, which is the formulation of the capacitance value of the ordinary electrical circuit, with the addition of the multiplication factor value k in the sharp area of the active electrode, because in that area the greatest plasma flow distance is obtained. The value of the multiplication factor  is obtained by fitting the curve between mathematical study and experiments. The I-V curve between the mathematical study and the corona discharge generation experiment has a high degree of similarity with the smallest percentage contacting point of 37.50%.The value of the multiplication factor  is influenced by the sharpness angle of the active electrode shape and the distance between the electrodes.
Zinc Oxide Nanoparticles (ZnONPs) Photocatalyst using Pulse Laser Ablation Method for Antibacterial in Water Polluted Fatkhiyatus Saadah; Rizka Zakiyatul Miskiyah; Ali Khumaeni
Journal of Physics and Its Applications Vol 2, No 2 (2020): May 2020
Publisher : Diponegoro University Semarang Indonesia

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.14710/jpa.v2i2.8001

Abstract

Synthesis of zinc oxide nanoparticles by pulse laser ablation method has been successed carried out. Synthesis was carried out in aquades medium with a repetition rate variation of 5 Hz, 10 Hz and 15 Hz pulse laser yielding brown colloids. The higher laser repetition rate, the colloidal color will be more dark brown. Characterization of zinc oxide nanoparticles includes UV-Vis, SEM-EDX, FTIR and XRD. The image of SEM shows that zinc oxide nanoparticles have a round shape. Measurement of particle distribution with imageJ software from SEM images showed that ZnO nanoparticles were 23.63 nm, 12.13 nm and 5.59 nm for 5 Hz, 10 Hz and 15 Hz shots. The EDX spectrum analysis results show that only Zn and O atoms in the ZnO nanoparticles colloid are synthesized. FTIR results showed that sprocket ZnO was formed at wave number 457 cm-1 and 545 cm-1. The XRD analysis results also show some peaks known as the ZnO phase. This indicates that ZnO nanoparticles have been formed. The testing of the antibacterial activity of ZnO nanoparticles using a liquid dilution method with nanoparticle concentrations of 40 ppm, 60 ppm and 80 ppm. The test results showed the percentage of degradation of Escherichia coli bacteria at concentrations of 40 ppm, 60 ppm and 80 ppm respectively at 89.60%, 97.76% and 98, 70%.
Synthesis of Zn-Fe nanoparticles using pulse laser ablation as a contrast agent in magnetic resonance imaging Nurul Hikmantiyah; Eko Hidayanto; Ali Khumaeni
Journal of Physics and Its Applications Vol 2, No 1 (2019): November 2019
Publisher : Diponegoro University Semarang Indonesia

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.14710/jpa.v2i1.6458

Abstract

Synthesis of zinc oxide nanoparticles, iron oxide nanoparticles and Zn-Fe nanoparticles using pulse laser ablation method has been conducted. Experimentally, a pulse Nd:YAG laser (1064 nm, 7 ns, 35 mJ) was directed and focused on a metal plates of pure Zn and Fe, which are placed in the liquid medium of polyvinyl pyrrolidone (PVP). The PVP functions as a stabilizer agent. The results show that the produced nanoparticles have a spherical shape with an averaged diameter of Zn-Fe nanoparticles of 13 nm. FTIR and XRD test results of Zn-Fe nanoparticles show characteristics of Zn-Fe compounds. The examination of Zn-Fe nanoparticles as MRI contrast agents was carried out by varying the concentration of nanoparticles. Cenh calculation results showed the highest contrast enhancement occurred at a concentration of 1.25 mM with a value of 64.26% for T1 weighted images, and 81.52% for T2 weighted images. The SNR calculation results show the highest value at a concentration of 1.25 mM of 70.52 for T1 weighted images. The highest SNR value in the T2 weighted image at a concentration of 0.156 mM of 165.09.
Characterization of Optical Properties of Colloidal Gold Solution based on Changes in Concentration using Light Polarization Method Winarno, Winarno; Firdausi, Ketut Sofjan; Soesanto, Qidir Maulana Binu; Khumaeni, Ali
Journal of Physics and Its Applications Vol 6, No 2 (2024): May 2024
Publisher : Diponegoro University Semarang Indonesia

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.14710/jpa.v6i2.22406

Abstract

This research was conducted to determine the effect of concentration on the characteristics of changes in the polarization angle of colloidal gold solutions. The method used in this research is natural polarization. The light source used was a green laser with a wavelength of 532 nm. The colloidal gold solution was obtained using the laser ablation method and then dissolved in aquabidest. The characteristics of changes in the angle of light polarization in the gold colloidal solution were obtained by varying the concentration of the gold colloidal solution (40 ppm, 30 ppm, 20 ppm, and 10 ppm). The results showed that gold colloids have optical activity because the orientation of the gold colloid molecules allows them to interact asymmetrically with linearly polarized light. In the range of concentration from 10 to 40 ppm, the polarization angle in gold colloids shows a linear pattern as a function of concentration. Within one month the colloidal gold sample showed stable properties. This method allows us to further analyze the quality of other types of colloids using the same method. This will improve our understanding of the interaction of polarized light with nanoparticles.