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    Determination and interference studies of bismuth by tungsten trap hydride generation atomic absorption spectrometry
    (Elsevier Science Bv, 2009) Kula, Ibrahim; Arslan, Yasin; Bakirdere, Sugin; Titretir, Serap; Kenduezler, Erdal; Ataman, O. Yavuz
    The determination of bismuth requires sufficiently sensitive procedures for detection at the mu g L-1 level or lower. W-coil was used for on-line trapping of volatile bismuth species using HGAAS (hydride generation atomic absorption spectrometry); atom trapping using a W-coil consists of three steps. Initially BiH3 gas is formed by hydride generation procedure. The analyte species in vapor form are transported through the W-coil trap held at 289 degrees C where trapping takes place. Following the preconcentration step, the W-coil is heated to 1348 degrees C; analyte species are released and transported to flame-heated quartz atom cell where the atomic signal is formed. In our study, interferences have been investigated in detail during Bi determination by hydride generation, both with and without trap in the same HGAAS system. Interferent/analyte (mass/mass) ratio was kept at 1, 10 and 100. Experiments were designed for carrier solutions having 1.0 M HNO3. Interferents such as Fe, Mn, Zn, Ni, Cu, As, Se. Cd, Pb, Au, Na, Mg, Ca, chloride, sulfate and phosphate were examined. The calibration plot for an 8.0 ml. sampling volume was linear between 0.10 mu g L-1 and 10.0 mu g L-1 of Bi. The detection limit (3 s/m) was 25 ng L-1. The enhancement factor for the characteristic concentration (C-o) was found to be 21 when compared with the regular system without trap, by using peak height values. The validation of the procedure was performed by the analysis of the certified water reference material and the result was found to be in good agreement with the certified values at the 95% confidence level. (C) 2009 Elsevier B.V. All rights reserved.
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    Determination of antimony by using tungsten trap atomic absorption spectrometry
    (Pergamon-Elsevier Science Ltd, 2008) Titretir, Serap; Kenduezler, Erdal; Arslan, Yasin; Kula, Ibrahim; Bakirdere, Sezgin; Ataman, O. Yavuz
    An electrically heated tungsten coil was used as a trap in the determination of antimony. The technique consists of three steps. Initially, SbH(3) is formed by hydride generation procedure; then the analyte species in vapor form are transported to W-coil trap heated at 370 degrees C. Following the preconcentration step, the trap is heated to 895 degrees C; analyte species are revolatilized and transported to the flame-heated quartz atom cell where atornization and the formation of signal take place. The experimental parameters were optimized both for trap and no-trap studies. The most important experimental parameters are concentrations of HCI and NaBH4 solutions. H2 and At gas flow rates. and collection and revolatilization temperatures of W-coil. Accuracy was tested using a certified reference material, waste water EU-L-1. Limit of detection for the system is 16 ng 1- 1 using a sample of 36 ml collected in 4.0 min. Enhancement factor in sensitivity was 17. (c) 2008 Elsevier B.V. All rights reserved.
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    The effect of 10 weeks of karate training on the development of motor skills in children who are new to karate
    (Frontiers Media Sa, 2024) Arslan, Yasin; Yavasoglu, Belma; Beykumul, Aysegul; Pekel, Aylin Ozge; Suveren, Ceren; Karabulut, Ebru Olcay; Ayyildiz Durhan, Tebessum
    This study investigated the effect of a 10-week karate training program on the motor skill development of 5-7-year-old children new to karate with two different test batteries. A total of 28 participants were included in the study: 18 in the Karate group and 10 in the control group. The karate group was subjected to a fundamental karate training (kihon) program consisting of 90-minute sessions four days a week for ten weeks in addition to physical education classes at their schools. In contrast, the control group did not participate in any sportive activities except physical education classes in their schools. Data were collected using the Eurofit test battery and the TGMD-2 test. In the pre-post test comparison of the anthropometric measurements of the karate group, no significant difference was found in the control group. In contrast, a significant difference was obtained in height, body mass index, and body fat percentage. In the post-test analysis of the two independent groups, there were statistically significant differences in favor of the karate group regarding height and body fat percentage (p < 0.005). In the pre-post analysis of the Eurofit test and the TGMD-2 for the karate group, all parameters showed statistically significant improvements (p < 0.001), while the control group showed no statistical difference. After comparing the karate and control groups, the Eurofit Test and TGMD-2 post-test results showed significantly higher scores (statistically significant differences) in all parameters for the karate group. In conclusion, the study shows that the 10-week karate training program positively affected the motor development of the participating children.
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    Effect of 6-week karate (kihon) and basic movement exercise on balance performance in visually impaired individuals
    (Frontiers Media Sa, 2023) Pekel, Aylin Ozge; Suveren, Ceren; Arslan, Yasin; Yavasoglu, Belma; Beykumul, Aysegul; Durhan, Tebessum Ayyildiz; Ceylan, Levent
    Today, the participation of visually impaired individuals in sports activities is essential. Because the ability to move independently starts to develop with a delay in visually impaired individuals, physical activity is necessary to compensate for developmental delay, eliminate the problem of independent movement in social life by reducing obstacle perception problems, develop self-confidence, and provide regular muscle activation and motivation to move. The study investigated the effect of 6 weeks of karate (kihon) and basic movement training on balance performance in individuals with congenital visual impairment. Fifteen visually impaired individuals aged between 10 and 14 participated in the study, and three groups were formed: experiment 1, experiment 2, and the control group. After the pre-tests were taken, the experimental groups received karate and basic movement training in addition to physical education classes for 6 weeks, while the control group received only physical education classes. When the study results were examined, there were highly significant differences between the pre- and post-test values of the groups receiving karate and basic movement training. At the same time, no progress was observed in the control group. In the post-test comparison of the karate and control groups, positive significance was found in the values of the karate group. In the same way, in the post-test comparison of the basic movement training group and the control group, positive progress was made in the basic movement training group. The post-test comparison of the basic movement training and karate groups was the same. As a result, it was concluded that basic movement training and karate exercises applied for 6 weeks positively affected the balance development in visually impaired individuals aged 10-14 years. No difference was found between the exercise protocols regarding effectiveness, and no improvement was observed in individuals who did not participate in any exercise.
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    Gas sensing through evanescent coupling of spoof surface acoustic waves
    (Elsevier Science Sa, 2019) Cicek, Ahmet; Arslan, Yasin; Trak, Digdem; Okay, Fatih Can; Kaya, Olgun Adem; Korozlu, Nurettin; Ulug, Bulent
    An ultrasonic gas sensor based on evanescent coupling of spoof surface acoustic waves between two surface phononic crystals containing trapezoidal grooves on rigid slabs is theoretically and experimentally demonstrated. Sensing properties for carbon dioxide in dry air at 25 degrees C and 760 Torr are investigated as an example. Band structure analyses reveal two spoof surface acoustic wave bands with opposite parities when the separation of surface phononic crystals is 1.5 times the periodicity of grooves. The beat length varies with frequency and carbon dioxide volume fraction, where the increase of the latter results in red shift of a sharp intense output peak at 59.69 kHz at a rate of 17.70 mHz/ppm and 16.20 mHz/ppm for carbon dioxide volume fractions up to 10,000 ppm, as measured through Finite-Element Method simulations and experiments, respectively. Gas sensing can also be achieved by measuring the output acoustic intensity at constant frequency, which exhibits a steep decrease with carbon dioxide volume fraction up to 2000 ppm.
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    One-dimensional surface phononic crystal ring resonator and its application in gas sensing
    (Amer Inst Physics, 2019) Kaya, Olgun Adem; Korozlu, Nurettin; Trak, Digdem; Arslan, Yasin; Cicek, Ahmet
    We introduce a ring resonator, which employs a one-dimensional phononic crystal on its inner surface, and investigate its performance as a gas sensor both numerically and experimentally. Having periodic equilateral trapezoidal protrusions, the ring resonator with 207 periods is optimized through band structure calculations via the finite-element method. A surface band linear around 58kHz is observed. The resonator exhibits sharp transmission peaks with a broad free-spectral range of 0.54kHz. Accordingly, a peak at 58.49kHz with a high-quality factor of 8196 appears. Application in detection of the carbon dioxide level in air with high sensitivity is demonstrated. The 58.49kHz peak red shifts linearly at 17.3mHz/ppm and 17.8mHz/ppm rates, as obtained from numerical calculations and experiments, respectively. Besides, the peak shape and maximum intensity are preserved. Due to the linear shift of the resonance peak with respect to the carbon dioxide concentration, acoustic intensity at initial peak frequency can be utilized as an auxiliary means for concentrations up to 1000ppm. The proposed ring resonator can be adapted to a variety of acoustic devices such as liquid concentration sensors based on phononic crystals, surface acoustic wave sensors, and micromechanical resonators.
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    Sensitivity improvement for antimony determination by using in-situ atom trapping in a slotted quartz tube and flame atomic absorption spectrometry
    (Pergamon-Elsevier Science Ltd, 2012) Titretir, Serap; Sik, Ahmet Inanc; Arslan, Yasin; Ataman, O. Yavuz
    Significant improvement has been achieved for antimony determination using a slotted quartz tube (SQT) as an atom trap (AT) for in situ preconcentration and flame atomic absorption spectrometry (FAAS). The suggested technique consists of trapping analyte species during ordinary nebulization followed by releasing the collected analyte via introducing organic solvent. Procedures and analytical figures of merit have been presented for the techniques called FAAS. SQT-FAAS and finally SQT-AT-FMS with the relevant comparisons. Analytical parameters, namely composition of the aqueous medium, sample flow rate, flame conditions, distance between burner head and SQT, sampling period and type of organic solvent and its volume have been optimized. Using SQT-AT-FAAS, a sensitivity enhancement of 369 fold has been obtained, 3 s limit of detection was 3.91 mu g L-1 when 25.0 mL of sample was collected in 4.0 min. Interference effects of some elements on antimony signal were studied. (c) 2012 Elsevier B.V. All rights reserved.
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    Ultrasonic Gas Sensing by Two-Dimensional Surface Phononic Crystal Ring Resonators
    (Amer Chemical Soc, 2019) Cicek, Ahmet; Trak, Digdem; Arslan, Yasin; Korozlu, Nurettin; Kaya, Olgun A.; Ulug, Bulent
    An acoustic ring resonator employing a two-dimensional surface phononic crystal is proposed for high-sensitivity detection in binary gas mixtures. Band analyses and frequency-domain simulations via the finite-element method reveal that a single band for spoof surface acoustic waves appears at ultrasonic frequencies around 58 kHz where modification of its dispersion due to varying gas composition results in a linear shift of the resonance frequency. The shift rate is -17.3 and 8.8 mHz/ppm for CO2 and CH4, respectively. The linear shift of resonance frequency is experimentally validated. In addition, the ring resonator can also be employed to track acoustic intensity variation with gas concentration, where exponentially decaying intensity for low concentrations leverages high-sensitivity operation.