Yazar "Akman, Hatice" seçeneğine göre listele

Listeleniyor 1 - 4 / 4
  • [ X ]
    Öğe
    High-sensitivity biomedical sensor based on photoacoustic and cavity enhanced absorption spectroscopy with a new software platform for breath analysis
    (The Optical Society, 2021) Bayraklı, İsmail; Akman, Hatice; Sarı, Filiz
    An easy-to-use highly sensitive sensor is reported for trace gas analysis. A near-infrared fiber-coupled external cavity diode laser in combination with a photoacoustic spectroscopy cell and a cavity enhanced absorption spectroscopy cell is used for analysis of trace gases. A software platform for direct absorption and wavelength modulation spectroscopy is developed in order to identify and quantify the molecules and to achieve a higher signal-to-noise ratio. Considering all of these features, the main advantage of our system is to analyze two different samples simultaneously and quickly. Trace gas measurement is assessed, and a detection limit of 1.5 ppb at 6528.76 cm(-1) for ammonia is demonstrated. Furthermore, the sensor with our software platform can be easily used outside of the laboratory, for example, in hospitals.
  • Küçük Resim
    Öğe
    Metabolism determination By soft computing methods from breath molecules
    (Sakarya Üniversitesi Fen Bilimleri Enstitüsü, 2022) Metlek, Sedat; Akman, Hatice; Bayraklı, İsmail
    The breath analysis is a non-invasive risk-free and painless method used to diagnose specific diseases. Since the breath analysis method is a new study field than the other methods, there are many unsettled standards and unknown parameters. Numerous complex metabolisms are constantly working in the human body. Therefore, there are numerous unknown molecular relationships. ANN can produce solutions in these unexplained situations. In our pilot study, breath of 19 healthy people has been analyzed. The TD / GC-MS method, which is an analytical method of breath analysis, has been used to detect molecules in the breaths. Using soft computing methods to the results of the 19 breath samples, the relation between fermentation and carbon hydrate metabolism has been associated with breath analysis technique. The results indicated that, there can be a relationship between these metabolisms. There must be done more studies for the exact results.
  • Küçük Resim
    Öğe
    Retraction: Metabolism Determination By Soft Computing Methods From Breath Molecules
    (Sakarya Üniversitesi, 2023) Metlek, Sedat; Akman, Hatice; Bayraklı, İsmail
    The article whose title is given above was retracted by the decision of the Editorial Board upon the request of the authors.
  • [ X ]
    Öğe
    Sensor using a photo-acoustic absorption cell with two perpendicular acoustic resonators to analyze multiple molecules
    (Optica Publishing Group (formerly OSA), 2023) Bayraklı, İsmail; Akman, Hatice; Sarı, Filiz
    An ultra-high sensitivity multi-molecule sensor based on a photo-acoustic cell with two perpendicular acoustic resonators and a common microphone has been reported. In this work, a 4.5 ?m distributed-feedback quantum cascade laser and a 1.5 ?mexternal cavity diode laser (EC-DL)were used as optical excitation sources. Considering the spectral ranges of the lasers used, it is possible to analyze eight molecules (QCL V N2Oand CO2, EC-DL:H2O, H2S, NH3, CO, CH4, and C2H2). The N2O molecule was used to evaluate the performance of the photo-acoustic spectroscopy (PAS)-based sensor. A sensitivity of 0.073 V/ppm and a linearity of 0.99 were found by analyzing the PAS signal as a function of N2O concentration at 2237.656 cm-1. The long-term performance of the sensor was determined by performing an Allan deviation analysis. A minimum detection limit of 9.8 ppb for 90 s integration time was achieved. The simultaneous multi-trace gas detection capability was verified by measurement of N2O, CO2, and H2O. Depending on the coarse/fine-tuning ranges of the lasers used, the number of molecules analyzed can be further increased. Such a sensor could provide simultaneous diagnosis of many diseases through an analysis of breath air and simultaneous monitoring of the most important greenhouse gases.