Investigation of the hydrogen production of the PACER fusion blanket integrated with Fe–Cl thermochemical water splitting cycle

Özkaya Medine,Acır Adem,Yalçın Şenay 한국원자력학회 2023 Nuclear Engineering and Technology Vol.55 No.11

In order to meet the energy demand, energy production must be done continuously. Hydrogen seems to be the best alternative for this energy production, because it is both an environmentally friendly and renewable energy source. In this study, the hydrogen fuel production of the peaceful nuclear explosives (PACER) fusion blanket as the energy source integrated with Fe–Cl thermochemical water splitting cycle have been investigated. Firstly, neutronic analyzes of the PACER fusion blanket were performed. Necessary neutronic studies were performed in the Monte Carlo calculation method. Molten salt fuel has been considered mole-fractions of heavy metal salt (ThF4, UF4 and ThF4+UF4) by 2, 6 and 12 mol. % with Flibe as the main constituent. Secondly, potential of the hydrogen fuel production as a result of the neutronic evaluations of the PACER fusion blanket integrated with Fe–Cl thermochemical cycle have been performed. In these calculations, tritium breeding (TBR), energy multiplication factor (M), thermal power ratio (1 ψ), total thermal power (Phpf ) and mass flow rate of hydrogen (m˙ H2 ) have been computed. As a results, the amount of the hydrogen production (m˙ H2 ) have been obtained in the range of 232.24x106 kg/year and 345.79 x106 kg/year for the all mole-fractions of heavy metal salts using in the blanket.

Electromyographic and Clinical Investigation of the Effect of Platelet-Rich Plasma on Peripheral Nerve Regeneration in Patients with Diabetes after Surgery for Carpal Tunnel Syndrome

Yasak Tuğçe,Özkaya Özay,Ergan Şahin Ayça,Çolak Özlem 대한성형외과학회 2022 Archives of Plastic Surgery Vol.49 No.1

Background Carpal tunnel syndrome (CTS) is the most common entrapment neuropathy. Studies have shown that results of CTS surgery are poorer in patients with diabetes. In this study, the effect of platelet-rich plasma (PRP) on nerve regeneration was investigated through clinical and electromyographic findings in patients with diabetes who underwent CTS surgery.Methods A retrospective analysis of 20 patients with diabetes who had surgically decompressed CTS was conducted. Patients were divided into two groups. The study group received PRP treatment following surgery. The control group did not receive any treatment. Patients were assessed using electromyography and the Boston Carpal Tunnel Syndrome Questionnaire preoperatively as well as postoperatively at 3-month, 6-month, and 1-year follow-ups visits.Results There was a decrease in complaints and an improvement in sensory and motor examinations in both groups. The Boston Carpal Tunnel Syndrome Questionnaire scores did not show any statistically significant differences between the two groups. However, electromyographic findings showed that there were statistical differences between preoperative and postoperative (3 months, 6 months, and 1 year) results in both groups. When the two groups were compared using preoperative and postoperative (3 months, 6 months, and 1 year) electromyographic values, no statistically significant differences were seen.Conclusion Single injections of PRP did not have a significant impact on median nerve regeneration following CTS surgery in patients with diabetes. The effectiveness of multiple PRP injections can be investigated in patients with diabetes in future studies.

Electromyographic and Clinical Investigation of the Effect of Platelet-Rich Plasma on Peripheral Nerve Regeneration in Patients with Diabetes after Surgery for Carpal Tunnel Syndrome

Yasak Tuğçe,Özkaya Özay,Ergan Şahin Ayça,Çolak Özlem 대한성형외과학회 2022 Archives of Plastic Surgery Vol.49 No.2

Background Carpal tunnel syndrome (CTS) is the most common entrapment neuropathy. Studies have shown that results of CTS surgery are poorer in patients with diabetes. In this study, the effect of platelet-rich plasma (PRP) on nerve regeneration was investigated through clinical and electromyographic findings in patients with diabetes who underwent CTS surgery.Methods A retrospective analysis of 20 patients with diabetes who had surgically decompressed CTS was conducted. Patients were divided into two groups. The study group received PRP treatment following surgery. The control group did not receive any treatment. Patients were assessed using electromyography and the Boston Carpal Tunnel Syndrome Questionnaire preoperatively as well as postoperatively at 3-month, 6-month, and 1-year follow-ups visits.Results There was a decrease in complaints and an improvement in sensory and motor examinations in both groups. The Boston Carpal Tunnel Syndrome Questionnaire scores did not show any statistically significant differences between the two groups. However, electromyographic findings showed that there were statistical differences between preoperative and postoperative (3 months, 6 months, and 1 year) results in both groups. When the two groups were compared using preoperative and postoperative (3 months, 6 months, and 1 year) electromyographic values, no statistically significant differences were seen.Conclusion Single injections of PRP did not have a significant impact on median nerve regeneration following CTS surgery in patients with diabetes. The effectiveness of multiple PRP injections can be investigated in patients with diabetes in future studies.

Thiol/Disulfide Homeostasis in Bipolar and Unipolar Depression

Gamze Erzin,Güven Özkaya,Canan Topçuoğlu,Rabia Nazik Yüksel,Özcan Erel,Emine Feyza Yurt,Erol Göka,Sinan Gülöksüz 대한정신약물학회 2020 CLINICAL PSYCHOPHARMACOLOGY AND NEUROSCIENCE Vol.18 No.3

Objective: Bipolar disorder and unipolar depressive disorder are complex phenotypes. There appear to be phenotypical, mechanistic, and therapeutic differences between bipolar depression (BD) and unipolar depression (UD). There is a need for understanding the underlying biological variation between these clinical entities. The role of oxidative processes underlying bipolar disorder and depression has been demonstrated. Thiol-disulfide homeostasis (TDH) is a recent oxidative stress marker. In this study, we aimed to inspect patients with bipolar depression and unipolar depression in terms of thiol-disulfide balance and to compare them with healthy controls. Methods: Patients admitted to the outpatient clinic of Ankara Numune Training and Research Hospital and diagnosed either as a depressive episode with bipolar disorder (n = 37) or unipolar depression (n = 24) according to DSM-5 criteria, along with healthy controls (HC) (n = 50), were included in the study. Native thiol, total thiol, and disulfide levels were compared across the groups. Results: In comparison to HC, both BD and UD groups had higher disulfide levels, disulfide/native thiol ratio, and disulfide/total thiol ratio. No significant differences between BD and UD were detected in terms of disulfide level, disulfide/ native thiol ratio, and disulfide/total thiol ratio. Conclusion: Increased levels of disulfide, native thiol, and disulfide/total thiol ratios compared to healthy controls in both UD and BD groups may be indicative of the presence of oxidative damage in these two clinical conditions. To clarify the role of oxidative stress in the pathophysiology of depressive disorders and investigate TDH, longitudinal studies in patients with medication-free UD and BD are required.

Vibrations of an axially accelerating, multiple supported flexible beam

S. Kural,E. Özkaya 국제구조공학회 2012 Structural Engineering and Mechanics, An Int'l Jou Vol.44 No.4

In this study, the transverse vibrations of an axially moving flexible beams resting on multiple supports are investigated. The time-dependent velocity is assumed to vary harmonically about a constant mean velocity. Simple-simple, fixed-fixed, simple-simple-simple and fixed-simple-fixed boundary conditions are considered. The equation of motion becomes independent from geometry and material properties and boundary conditions, since equation is expressed in terms of dimensionless quantities. Then the equation is obtained by assuming small flexural rigidity. For this case, the fourth order spatial derivative multiplies a small parameter; the mathematical model converts to a boundary layer type of problem. Perturbation techniques (The Method of Multiple Scales and The Method of Matched Asymptotic Expansions) are applied to the equation of motion to obtain approximate analytical solutions. Outer expansion solution is obtained by using MMS (The Method of Multiple Scales) and it is observed that this solution does not satisfy the boundary conditions for moment and incline. In order to eliminate this problem, inner solutions are obtained by employing a second expansion near the both ends of the flexible beam. Then the outer and the inner expansion solutions are combined to obtain composite solution which approximately satisfying all the boundary conditions. Effects of axial speed and flexural rigidity on first and second natural frequency of system are investigated. And obtained results are compared with older studies.

INVESTIGATION OF LEACHATE RECIRCULATION EFFECT IN SANITARY LANDFILL SITE

( Ahmet Demir ),( Adem Baştürk ),( Bestamin Özkaya ),( M. Sinan Bilgili ) 한국폐기물자원순환학회 2002 APLAS Vol.2002 No.1

In this study, the effect of leachate recirculation on waste stabilization was investigated at Odayeri Sanitary Landfill, which locates in the European side of Istanbul. For this purpose, 1,5 hectares (test area) of the landfill area (Odayeri), and two test cells with the dimensions of 25×50×5 m. were used. Vertical injection wells method was used at test area, and surface drainage method was used at test cells for leachate recirculation. Findings obtained from this study are evaluated.

위생매립지에서 침출수 재순환의 효과 조사

( Ahmet Demir ),( Adem Baştürx ),( Bestamin Özkaya ),( M. Sinan Bilgili ) 한국폐기물자원순환학회 2002 APLAS Vol.2002 No.2

본 논문에서 폐기물 안정성에 미치는 침출수 재순환의 효율은 이스탄불의 유럽방향에 위치한 Odayeri 위생매립지에서 조사하였다. 이러한 목적은 매립지의 1.5 hectares(실험지 역)와 25×50×5m 부피의 두 개의 실험용 셀을 이용하였다. 수직으로 주입하는 방식은 실험지역에서 사용하였고, 표면 배수 방식은 침출수 재순환을 위한 실험용 셀에 이용하였다. 본 논문에서 얻어진 결과를 평가한다. In this study, the effect of leachate recirculation on waste stabilization was investigated at Odayeri Sanitary Landfill, which locates in the European side of Istanbul. For this purpose, 1,5 hectares (test area) of the landfill area (Odayeri), and two test cells with the dimensions of 25×50×5 m. were used. Vertical injection wells method was used at test area, and surface drainage method was used at test cells for leachate recirculation. Findings obtained from this study are evaluated.

Hybrid Magnetic‑Piezoelectric Energy Harvester for Power Generation around Waistline During Gait

Mustafa İlker Beyaz,Fatih Tat,Kamil Yunus Özkaya,Ramazan Özbek 대한전기학회 2020 Journal of Electrical Engineering & Technology Vol.15 No.1

The development of a novel hybrid energy harvester for scavenging power around human waistline is presented. The harvester is composed of mm-scale electromagnetic coils and piezoelectric transducers incorporated on a belt, as well as permanent magnet structures placed on wristbands. The coils and transducers are positioned on the belt such that they correspond to either sides of the waist, facing the wrists and the hipbone. This confguration leads to simultaneous power generation on the coils and transducers due to swinging arm motion and varying belt stress during gait, respectively. Moderate walking at 1 m/s resulted in a peak open circuit voltage of 2.8 V on the coils, reaching up to 4.3 V at 2 m/s fast walking. The open circuit voltage obtained from the transducers varied from 5.2 to 9 V, corresponding to moderate walking at 1 m/s and running at a speed of 3 m/s, respectively. Instantaneous AC power was characterized separately at 1 m/s walking speed, and measured to be 14 mW and 13.5 μW from the coils and piezoelectric transducers, respectively. The two harvesting mechanisms were coupled with rectifers and DC/DC converter circuitry to store energy in an onboard 20 mAh 3 V LiPo battery. Walking for 10 min was shown to raise the battery voltage from 2.2 to 2.8 V. The results reported here demonstrate the feasibility of this MEMS-scale harvesting scheme to recharge batteries of portable electronic devices.

Non linear vibrations of stepped beam systems using artificial neural networks

S. M. Ba datli,E. Özkaya,H.A. Özyi it,A. Tekin 국제구조공학회 2009 Structural Engineering and Mechanics, An Int'l Jou Vol.33 No.1

In this study, the nonlinear vibrations of stepped beams having different boundary conditions were investigated. The equations of motions were obtained by using Hamilton’s principle and made non dimensional. The stretching effect induced non-linear terms to the equations. Natural frequencies are calculated for different boundary conditions, stepped ratios and stepped locations by Newton-Raphson Method. The corresponding nonlinear correction coefficients are also calculated for the fundamental mode. At the second part, an alternative method is produced for the analysis. The calculated natural frequencies and nonlinear corrections are used for training an artificial neural network (ANN) program which has a multi-layer, feed-forward, back-propagation algorithm. The results of the algorithm produce errors less than 2.5% for linear case and 10.12% for nonlinear case. The errors are much lower for most cases except clamped-clamped end condition. By employing the ANN algorithm, the natural frequencies and nonlinear corrections are easily calculated by little errors, and the computational time is drastically reduced compared with the conventional numerical techniques.

Comparison of The Thickness of Free Anterolateral Thigh Flap in Different Fascial Planes: Clinical Results of Subfascial and Superficial Fat Flap

Tuluy Yavuz,Bali Zülfükar Ulaş,Ünsal Merve Özkaya,Parspancı Aziz,Yoleri Levent,Çiçek Çağla,Filinte Gaye Taylan 대한성형외과학회 2023 Archives of Plastic Surgery Vol.50 No.6

Background The anterolateral thigh (ALT) flap is a preferred option in the reconstruction of a wide variety of defects, enabling multiple tissue components and thicknesses.Methods This study was conducted to investigate the correlation of the thickness of the traditional subfascial ALT flap and superficial fat flap with age, gender, and body mass index (BMI). A total of 42 patients (28 males and 14 females) were included in the study.Results Mean age was 50.2 (range, 16–75) years and mean BMI was 24.68 ± 4.02 (range, 16.5–34.7) kg/m2. The subfascial flap thickness was significantly thinner in male patients (16.07 ± 2.77 mm) than in female patients (24.07 ± 3.93 mm; p < 0.05), whereas no significant difference was found between male (4.28 ± 1.15 mm) and female patients (4.85 ± 1.09 mm) regarding superficial fat flap thickness (p = 0.13). The thickness of both flaps had a positive correlation with BMI, and the strongest correlation was found for subfascial ALT thickness in female patients (r = 0.81). Age had no effect on both flap thickness measurements. The anterior thigh is thicker in women than in men, although it varies according to BMI. This shows that flap elevation is important in the superthin plane, especially if a thin flap is desired in female patients in defect reconstruction with the ALT flap. Thus, a single-stage reconstruction is achieved without the need for a defatting procedure after subfascial dissection or a second defatting procedure 3 to 6 months later.Conclusion The appropriate ALT flap plane should be selected considering the gender and BMI of the patient.