Browsing by Author "Eseller, Kemal Efe"

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Citation Count: 58
Analysis of bakery products by laser-induced breakdown spectroscopy
(Elsevier Sci Ltd, 2015) Bilge, Gonca; Boyaci, Ismail Hakki; Eseller, Kemal Efe; Tamer, Ugur; Cakir, Serhat; Department of Electrical & Electronics Engineering
In this study, we focused on the detection of Na in bakery products by using laser-induced breakdown spectroscopy (LIBS) as a quick and simple method. LIBS experiments were performed to examine the Na at 589 nm to quantify NaCl. A series of standard bread sample pellets containing various concentrations of NaCl (0.025-3.5%) were used to construct the calibration curves and to determine the detection limits of the measurements. Calibration graphs were drawn to indicate functions of NaCl and Na concentrations, which showed good linearity in the range of 0.025-3.5% NaCl and 0.01-1.4% Na concentrations with correlation coefficients (R-2) values greater than 0.98 and 0.96. The obtained detection limits for NaCl and Na were 175 and 69 ppm, respectively. Performed experimental studies showed that LIBS is a convenient method for commercial bakery products to quantify NaCl concentrations as a rapid and in situ technique. (C) 2015 Elsevier Ltd. All rights reserved.
Citation Count: 37
Ash analysis of flour sample by using laser-induced breakdown spectroscopy
(Pergamon-elsevier Science Ltd, 2016) Bilge, Gonca; Sezer, Banu; Eseller, Kemal Efe; Berberoglu, Halil; Koksel, Hamit; Boyaci, Ismail Hakki; Department of Electrical & Electronics Engineering
Ash content is,a measure of total mineral content in flour. It is also an important quality parameter in terms of nutritional labeling as well as processing properties of various cereal products. However, laboratory analysis takes a long time (5-6 h) and results in considerable waste of energy. Therefore, the aim of the study was to develop a new method for ash analysis in wheat flour by using laser induced breakdown spectroscopy (LIBS). LIBS is a multi-elemental, quick and simple spectroscopic method. Unlike basic ash analysis method, it has the potential to analyze a sample in a considerably short time. In the study, wheat flours with different ash contents were analyzed using LIBS and the spectra were evaluated with partial least squares (PLS) method. The results were correlated with the ones taken from standard ash analysis method. Calibration graph showed good linearity with the ash content between 0.48 and 1.39%, and 0.992 coefficient of determination (R-2). Limit of detection for ash analysis was calculated as 0.026%. The results indicated that LIBS is a promising and reliable method with high sensitivity for routine ash analysis in flour samples. (C) 2016 Elsevier B.V. All rights reserved.
Citation Count: 0
Blood metal analysis of plasmas from donors with and without SARS-CoV-2 using laser-induced breakdown spectroscopy and logistic regression
(Optica Publishing Group, 2024) Melikechi, Noureddine; Adler, Helmar G.; Safi, Ali; Landis, Joshua E.; Pourkamali-Anaraki, Farhad; Eseller, Kemal Efe; Xia, Weiming; Department of Electrical & Electronics Engineering
Research on the correlation between metal levels in blood and Covid-19 infection has been conducted primarily by assessing how each individual blood metal is linked to different aspects of the disease using samples from donors with various levels of severity to Covid-19 infection. Using logistics regression on LIBS spectra of plasma samples collected pre- and postCovid-19 pandemic from donors known to have developed various levels of antibodies to the SARS-Cov-2 virus, we show that relying on the levels of Na, K, and Mg together is more efficient at differentiating the two types of plasma samples than any single blood alone.
Citation Count: 0
Classification of Different Recycled Rubber-Epoxy Composite Based on Their Hardness Using Laser-Induced Breakdown Spectroscopy (LIBS) with Comparison Machine Learning Algorithms
(Mdpi, 2023) Yilmaz, Vadi Su; Eseller, Kemal Efe; Aslan, Ozgur; Bayraktar, Emin; Electrical-Electronics Engineering; Mechanical Engineering; Department of Electrical & Electronics Engineering
This paper aims toward the successful detection of harmful materials in a substance by integrating machine learning (ML) into laser-induced breakdown spectroscopy (LIBS). LIBS is used to distinguish five different synthetic polymers where eight different heavy material contents are also detected by LIBS. Each material intensity-wavelength graph is obtained and the dataset is constructed for classification by a machine learning (ML) algorithm. Seven popular machine learning algorithms are applied to the dataset which include eight different substances with their wavelength-intensity value. Machine learning algorithms are used to train the dataset, results are discussed and which classification algorithm is appropriate for this dataset is determined.
Citation Count: 1
Combustion applications of laser-induced breakdown spectroscopy
(Elsevier, 2020) Yueh,F.Y.; Tripathi,M.M.; Singh,J.P.; Sezer,B.; Eseller,K.E.; Department of Electrical & Electronics Engineering
The laser-induced breakdown spectroscopy (LIBS) technique has the capability to perform multielemental, remote, online, in situ analysis with no/minimum sample preparations. LIBS has created a great deal of interest in combustion diagnostic research. In this chapter, LIBS capabilities in combustion diagnostics and monitoring engine and flame characteristics are investigated. © 2020 Elsevier B.V. All rights reserved.
Citation Count: 5
Comparison of different calibration techniques of laser induced breakdown spectroscopy in bakery products: on NaCl measurement
(Springer, 2021) Bilge, Gonca; Eseller, Kemal Efe; Berberoglu, Halil; Sezer, Banu; Tamer, Ugur; Boyaci, Ismail Hakki; Department of Electrical & Electronics Engineering
Laser induced breakdown spectroscopy (LIBS) is a rapid optical spectroscopy technique for elemental determination, which has been used for quantitative analysis in many fields. However, the calibration involving atomic emission intensity and sample concentration, is still a challenge due to physical-chemical matrix effect of samples and fluctuations of experimental parameters. To overcome these problems, various chemometric data analysis techniques have been combined with LIBS technique. In this study, LIBS was used to show its potential as a routine analysis for Na measurements in bakery products. A series of standard bread samples containing various concentrations of NaCl (0.025%-3.5%) was prepared to compare different calibration techniques. Standard calibration curve (SCC), artificial neural network (ANN) and partial least square (PLS) techniques were used as calibration strategies. Among them, PLS was found to be more efficient for predicting the Na concentrations in bakery products with an increase in coefficient of determination value from 0.961 to 0.999 for standard bread samples and from 0.788 to 0.943 for commercial products.
Data analysis software development of laser induced breakdown spectroscopy (LIBS)
(2021) Gundoz, Omer Abduljabbar Mohhammed Al; Eseller, Kemal Efe; Department of Electrical & Electronics Engineering
Laser induced breakdown spectroscopy is a useful growing technique. The research's on LIBS is gaining importance in instrumentation and data analysis fields because it has a large number of applications in different fields especially in industrial, scientific investigation, medical, and many other fields .this study views a theoretical base of the libs technique as well as the setup of libs including new set up which are the portable libs set up which are getting more attention in recent works due to the ease of use and accurate results. From the analytical point of view, LIBS is usually characterized by direct laser ablation. And also the competition is made through a database which is explaining the different elements due to different wavelength and their intensities, which will refer in the end to the elements that the sample consist of: The database being used is coming from the laboratory with multiple experiences. also, this work will focus on detecting specific elements which are FE,CU,ZN,AL and MG. Key Words: laser, ablation, plasma, spectrometer, fiber optics, q.switch , lens
Citation Count: 0
Design Optimization of Cassegrain Telescope for Remote Explosive Trace Detection
(Spie-int Soc Optical Engineering, 2017) Bhavsar, Kaushalkumar; Eseller, K. E.; Prabhu, Radhakrishna; Department of Electrical & Electronics Engineering
The past three years have seen a global increase in explosive-based terror attacks. The widespread use of improvised explosives and anti-personnel landmines have caused thousands of civilian casualties across the world. Current scenario of globalized civilization threat from terror drives the need to improve the performance and capabilities of standoff explosive trace detection devices to be able to anticipate the threat from a safe distance to prevent explosions and save human lives. In recent years, laser-induced breakdown spectroscopy (LIBS) is an emerging approach for material or elemental investigations. All the principle elements on the surface are detectable in a single measurement using LIBS and hence, a standoff LIBS based method has been used to remotely detect explosive traces from several to tens of metres distance. The most important component of LIBS based standoff explosive trace detection system is the telescope which enables remote identification of chemical constituents of the explosives. However, in a compact LIBS system where Cassegrain telescope serves the purpose of laser beam delivery and light collection, need a design optimization of the telescope system. This paper reports design optimization of a Cassegrain telescope to detect explosives remotely for LIBS system. A design optimization of Schmidt corrector plate was carried out for Nd:YAG laser. Effect of different design parameters was investigated to eliminate spherical aberration in the system. Effect of different laser wavelengths on the Schmidt corrector design was also investigated for the standoff LIBS system.
Citation Count: 25
Determination of Ca addition to the wheat flour by using laser-induced breakdown spectroscopy (LIBS)
(Springer, 2016) Bilge, Gonca; Sezer, Banu; Eseller, Kemal Efe; Berberoglu, Halil; Koksel, Hamit; Boyaci, Ismail Hakki; Department of Electrical & Electronics Engineering
The aim of the study was to determine Ca addition to the flour by using laser-induced breakdown spectroscopy (LIBS) as a quick and simple multi-elemental spectroscopy method. Different amounts of CaCO3-added wheat flour were analyzed using LIBS to determine Ca content and Ca/K ratio, which is used for discrimination of natural and Ca-added flour. LIBS spectra were quantitatively evaluated with partial least square (PLS) method as a multivariate data analysis method to eliminate the matrix effect. Ca and Ca/K calibration graphs of PLS method showed good linearity with coefficient of determinations (R (2)) 0.999. Limit of detection values for Ca and Ca/K analysis were calculated as 25.9 ppm and 0.013, respectively. Furthermore, the results were found to be consistent with the data obtained from atomic absorption spectroscopy method as a reference method for flour samples.
Citation Count: 81
Determination of whey adulteration in milk powder by using laser induced breakdown spectroscopy
(Elsevier Sci Ltd, 2016) Bilge, Gonca; Sezer, Banu; Eseller, Kemal Efe; Berberoglu, Halil; Topcu, Ali; Boyaci, Ismail Hakki; Department of Electrical & Electronics Engineering
A rapid and in situ method has been developed to detect and quantify adulterated milk powder through adding whey powder by using laser induced breakdown spectroscopy (LIBS). The methodology is based on elemental composition differences between milk and whey products. Milk powder, sweet and acid whey powders were produced as standard samples, and milk powder was adulterated with whey powders. Based on LIBS spectra of standard samples and commercial products, species was identified using principle component analysis (PCA) method, and discrimination rate of milk and whey powders was found as 80.5%. Calibration curves were obtained with partial least squares regression (PLS). Correlation coefficient (R-2) and limit of detection (LOD) values were 0.981 and 1.55% for adulteration with sweet whey powder, and 0.985 and 0.55% for adulteration with acid whey powder, respectively. The results were found to be consistent with the data from inductively coupled plasma-mass spectrometer (ICP-MS) method. (C) 2016 Elsevier Ltd. All rights reserved.
El tipi lazer-oluşturmalı plazma spektroskopisi (LIBS) aygıtı geliştirilmesi
(2021) Aktepe, Mustafa; Eseller, Kemal Efe; Berberoğlu, Halil; Department of Electrical & Electronics Engineering
Bu tezde, makine öğrenmesi algoritmalarını kullanarak örnekleri birbirinden ayırt edebilen bir el tipi sistem geliştirdik. Bu tezin temel amacı, yüksek enerjili malzemeleri ayırt etmek için temel oluşturan bir sistem geliştirmektir. Bu sistem, C (248 nm, 1069 nm), O (777 nm, 926 nm), H (656 nm,486 nm), N (868nm, 1011 nm), San Bantları (300 nm – 650 nm) gibi element ve moleküllere sahip olan yüksek enerjili malzemeleri niteliksel ve niceliksel olarak analiz edebilir. Bu elementlerin ve moleküllerin dalga boyu bilgileri Ulusal Standartlar ve Teknoloji Enstitüsü (NIST) veri tabanından elde edilmiştir. Bu sistem, örnekleri analiz etmek ve belirlemek için makine öğrenme algoritması (Destek Vektör Makinesi/SVM) kullanır. El tipi bir sistem olarak geliştirilen bu sistem, sonuç olarak tüm kontrol, iletişim ve kullanıcı ara yüzü (UI) mekanizmaları için gömülü platformda geliştirilmiştir. Bu amaçla ST Microelectronics tarafından geliştirilen ve STM32F746ZGT6 modeli olan ARM (ARM Cortex M7) tabanlı mikro denetleyici birimi (MCU) kullanıyoruz.
Citation Count: 3
Food science application
(Elsevier, 2020) Eseller,K.E.; Boyaci,I.H.; Sezer,B.; Bilge,G.; Berberoglu,H.; Department of Electrical & Electronics Engineering
One of the main issues in the food industry is to determine quality and authenticity, and to detect adulteration, which causes a great deal of concern among consumers and risk in brand reputation for manufacturers. Food quality control is a wide playing field that includes different participants such as consumers, manufacturers, legislative bodies, researchers, etc. with an individual perspective for each participant, including economic and environmental contexts. But the ultimate goal is to produce safe and healthy food products. The preferential choice of food items depends on individuals’ lifestyles, diets, health, religious beliefs, current trends, etc. This brings about the issues of accurate labeling, fair trade, and consumer's health. The analysis of food and capabilities and limitations of laser-induced breakdown spectroscopy (LIBS) on foods have been reported. This chapter provides an overview of applications on food quality and the monitoring of several foods, sampling techniques, and limitations of LIBS. © 2020 Elsevier B.V. All rights reserved.
Citation Count: 111
Identification of meat species by using laser-induced breakdown spectroscopy
(Elsevier Sci Ltd, 2016) Bilge, Gonca; Velioglu, Hasan Murat; Sezer, Banu; Eseller, Kemal Efe; Boyaci, Ismail Hakki; Department of Electrical & Electronics Engineering
The aim of the present study is to identify meat speciesby using laser-induced breakdown spectroscopy (LIBS). Elemental composition differences between meat species were used for meat identification. For this purpose, certain amounts of pork, beef and chicken were collected from different sources and prepared as pellet form for LIBS measurements. The obtained LIBS spectra were evaluated with some chemometric methods, and meat species were qualitatively discriminated with principal component analysis (PCA) method with 83.37% ratio. Pork beef and chicken-beef meat mixtures were also analyzed with partial least square (PLS) method quantitatively. Determination coefficient (R-2) and limit of detection (LOD) values were found as 0.994 and 4.4% for pork adulterated beef, and 0.999 and 2.0% for chicken adulterated beef, respectively. In the light of the findings, it was seen that LIBS can be a valuable tool for quality control measurements of meat as a routine method. (C) 2016 Elsevier Ltd. All rights reserved.
Citation Count: 1
Laser induced breakdown spectroscopy based diffusion modelling in cheese matrix
(Elsevier Sci Ltd, 2019) Sezer, Banu; Bilge, Gonca; Eseller, Kemal Efe; Berberoglu, Halil; Boyaci, Ismail Hakki; Department of Electrical & Electronics Engineering
In the cheese industry, mass transfer of small solutes like salt during brining and ripening is extremely important for the quality of final products. In general, effective diffusion coefficient values have been reported in the studies using destructive concentration profile methods. This study aims to monitor NaCl diffusion in cheese by using laser induced breakdown spectroscopy (LIBS) as a nondestructive method to fulfill the requirement of measuring mass transfer properties of solutes in microscopic size complex heterogeneous structures. To this end, spherical shaped white cheese samples were brined in 16% salt solution for 5-210 min and overnight, and Na emission lines were monitored by scanning the cross-section of each sample at 30 points on the radial axis. As was expected, increasing brining time decreased the concentration difference between the center and edge of the cheese samples. Experimental results were fitted to Fick's Diffusion Equation. It was observed that NaCl distribution became uniform and equal at different locations of the cheese sample after 13.8 h. All these results have demonstrated that LIBS can be utilized for optimization of the brining conditions of cheese. Although the use of LIBS in this study was limited to parameter optimization, it can also be applied for real time monitoring of food processes due to its rapid and continuous measurement mode.
LIBS ile metallerde iz elementlerinin saptanması
(2017) Ekrım, Mohamed Lotfı; Eseller, Kemal Efe; Department of Electrical & Electronics Engineering
Iz Elementi, belirli bir numune veya ortamda yalnızca çok küçük miktarlarda bulunan kimyasal bir elementtir. Krom, kobalt, bakır, demir, manganez, magnezyum, çinko ve canlı organizmaların bileşenleri olarak çok az miktarda bulunan diğer elementler, büyümeleri, gelişmeleri ve sağlığı için gereklidir. Bu tezde lazerle indüklenen parçalanma spektroskopisi LIBS kullanarak elementleri tespit etmek için bir deney yaptım.
LIBS kullanılarak MATLAB temelinde ince filmlere ait yapı analizi
(2021) Azouz, Omaro A.; Eseller, Kemal Efe; Department of Electrical & Electronics Engineering
Bu tezde, farklı dalga boylarında foton (ışık) salan ve NIST verileri ile karşılaştırılan, her bir numunedeki elementleri ve konsantrasyonunu belirlemek için kullanılabilir olan, numunenin belirli bir alanına lazer atışını kullanan bir tür atomik emisyon tekniği olan Lazerle indüklenmiş plazma Spektroskopisi (LIBS) yöntemi ile çalıştık. Çalışmamızda Lorentzian uyumu kullanarak tepe ve alt noktaları belirlemek için bir MATLAB kodu geliştirdik. Böylece her tepe noktasının altındaki alan yüzdesini hesaplayabilir ve sonuçları diğer yöntemlerle Origin yazılımı ve Excel kullanarak karşılaştırabildik. Her bir atış için RSD, LOD ve SNR ve gürültü dalgalanmasını hesaplanmıştır. Numune CVD ile hazırlandı ve bu çalışmada LIBS Modelini ((LPS-1064-A 50mJ) kullandık; Başlangıç Dalgaboyu 186.263 nm, Bitiş Dalgaboyu: 888.604 nm, Geçit Gecikmesi: 0.350, Geçit Genişliği (ms): 1.050 dir. Belirli bir program kullanılarak yapılan hesaplama, her tepe noktasının altındaki Alan yüzdesine ilişkin özdeş sonuçları gösterdi ve her dalga boyunda birinci ve ikinci atışta anormal tepki olmasına rağmen, foton emisyon etkisi normal hale geldi. Numune üzerinde Sn, Mg, Fe, Al, Cu, S, Si, Zn elementleri analizleri yapıldı.
MERAK ETTİĞİMİZ GEZEGEN “MARS” ve LAZER SPEKTROSKOPİSİ
(Bilim ve Teknoloji, 2014) Eseller, Kemal Efe; Department of Electrical & Electronics Engineering
Bilim insanları, evrende gerçekleşen olayları merak ettiği sürece hayatı kolaylaştıran yeni buluşlara ulaşacak ve her geçen gün bilime daha fazla katkı sağlayacaklardır. Amerikan Havacılık ve Uzay Ajansı (NASA), Mars gezegenine gönderdiği Curiosity (merak) - Rover sistemi ile gezegende çok önceden yaşamış canlı kalıntılarını (mikroplar, tek hücreli canlılar) bulabilmek için araştırmalar yapmakta ve gezegenin tarihi oluşumunu incelemektedir. Mars yüzeyinde, insanoğlu için gerekli Sülfür (S), Nitrojen (N), Oksijen (O), Fosfor (P) ve Karbon (C) gibi elementlerin varlığı ve izleri, gelecekte bu konuda yapılacak araştırma konularını şekillendirmekte ve uygun yaşam koşullarının bulunması için zemin hazırlamaktadır.
Optoelektronik malzemelerin analizi
(2017) Alqurqash, Ayoob Yousıf Ahmed; Eseller, Kemal Efe; Department of Electrical & Electronics Engineering
Optoelektronik, ışığın yayılımı ve algılanması LED'lerin, güneş pillerinin, transistörlerin, ve fotodetektörlerin yapısı ve üretimi ile ilgili olan bir anabilim dalıdr. Cihazların sentezlenmesinde kullanılan malzemeler, (Silikon, MWCNT, SWCNT ve Grafen) radyasyon ışığını elektriğe veya tersine dönüştürme kapasitesine göre değişim göstermektedir. Bu tez, optoelektronik sistemlerde özellikle karbondan (grafit, fulleren, CNT, MWCNT, SWCNT ve Grafen) üretilen malzemelerin kökenini temsil eden grafen materyalinde bulunan karbon nanotüp malzemelerin analizini incelemekte ve MWCNT'lerin istisnai özelliklerini vurgulamaktadır. MWCNT numunesi üzerindeki deneyler, güç lazeri (200mW, 100mW, 50mW) ve dalga boyu 532nm olan Raman spektrometresi kullanılarak gerçekleştirilmiştir.
Citation Count: 13
Performance evaluation of laser induced breakdown spectroscopy in the measurement of liquid and solid samples
(Pergamon-elsevier Science Ltd, 2018) Bilge, Gonca; Sezer, Banu; Boyaci, Ismail Hakki; Eseller, Kemal Efe; Berberoglu, Halil; Department of Electrical & Electronics Engineering
Liquid analysis by using LIBS is a complicated process due to difficulties encountered during the collection of light and formation of plasma in liquid. To avoid these, some applications are performed such as aerosol formation and transforming liquid into solid state. However, performance of LIBS in liquid samples still remains a challenging issue. In this study, performance evaluation of LIBS and parameter optimizations in liquid and solid phase samples were performed. For this purpose,milk was chosen as model sample; milk powder was used as solid sample, and milk was used as liquid sample in the experiments. Different experimental setups have been constructed for each sampling technique, and optimizations were performed to determine suitable parameters such as delay time, laser energy, repetition rate and speed of rotary table for solid sampling technique,and flow rate of carrier gas for liquid sampling technique. Target element was determined as Ca, which is a critically important element in milk for determining its nutritional value and Ca addition. In optimum parameters, limit of detection (LOD), limit of quantification (LOQ) and relative standard deviation (RSD) values were calculated as 0.11%, 0.36% and 8.29% respectively for milk powders samples; while LOD, LOQ and RSD values were calculated as 0.24%, 0.81%, and 10.93% respectively for milk samples. It can be said that LIBS is an applicable method in both liquid and solid samples with suitable systems and parameters. However, liquid analysis requires much more developed systems for more accurate results. (C) 2018 Elsevier B.V.All rights reserved.
Citation Count: 0
Performance evaluation of self-mixing interferometer with the ceramic type piezoelectric accelerometers
(de Gruyter Poland Sp Z O O, 2022) Berberoglu, Halil; Tiken, Mehmet; Eseller, Kemal Efe; Orhan, Elif; Candan, Can; Department of Electrical & Electronics Engineering
In this article, reconstructed displacement from the self-mixing signal is compared with the displacement obtained by the ceramic shear mode design piezoelectric accelerometer. Piezoelectric accelerometers are widely accepted due to the low output noise and wide frequency range, but nevertheless it is not contact-free. Self-mixing interferometric signals due to the vibrating target on which an accelerometer is attached are acquired by an external silicon type photodetector. The laser light hits directly the accelerometer as a target which is driven by the sum of two different sinusoidal frequencies of 150 and 300 Hz with different voltage levels.