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© 2022 Hydrogen Energy Publications LLCMetal hydride (MH) storage is known as a safe storage method because it does not require complex processes like high pressure or very low temperature. However, it is necessary to use a heat exchanger due to the endothermic and exothermic reactions occurring during the charging and discharging processes of the MH tanks. The performance of the MH is adversely affected by the lack of a heat exchanger or a suitable temperature range and it causes non-stable hydrogen supply to the fuel cell systems. In this study, effect of the tank surface temperature on hydrogen flow and hydrogen consumption performance were investigated for the MH hydrogen storage system of a hydrogen Fuel Cell Electric Vehicle (FCEV). Different temperature values were arranged using an external heat circulator device and a heat exchanger inside the MH tank. The fuel cell (FC) was operated at three different power levels (200 W, 400 W, and 600 W) and its performance was determined depending on the temperature and discharge flow rate of the MH tank. When the heat exchanger temperature (HET) was set to 40 °C, the discharge performance of the MH tank increased compared to lower temperatures. For example, when the FC power was set to 200 W and the HET of the system was at 40 °C, 1600 L hydrogen was supplied to the FC and 2000 Wh electrical energy was obtained. The results show that the amount of hydrogen supplied from the MH tank decreases significantly by increasing the flow rate in the system and rapid temperature changes occur in the MH tank.

© 2021 Hydrogen Energy Publications LLCIn this study, hydrogen evolution electrodes are prepared by a 3D printing method using conductive PLA filament. To improve their conductivity and electrochemical performance, Nickel–Copper (NiCu) binary coating is deposited on 3D printed (3DP) electrodes in a solution bath with different volume ratios. Electrodes have been prepared as NixCux, NixCu2x, and NixCu3x according to Ni and Cu volume ratio (Ni–Cu; 10-10, 10–20, and 10–30 mL, respectively). Surface morphologies of the samples are measured using FE-SEM, EDX and XRD techniques. Electrochemical characterizations are investigated by LSV, CV and EIS. According to the results, the current density of NiCu coated 3DP electrodes is higher than the uncoated 3DP electrode. The results show that the resistance values of the electrodes are decreased from 0.262 kΩ to 0.187 kΩ in NixCu3x electrode.

Hydrogen production from the electrolysis of water by sea or lake waters used as electrolyte plays a crucial role in providing sustainable hydrogen production. Production of hydrogen from these natural sources is highly utilized from small scale to complex applications due to water resources' inconsumable potential. In this study, the hydrogen production potential of Turkey's different regions such as the Black Sea, Aegean Sea, Marmara Sea, Mediterranean Sea, Lake Van, Agcas, ar Dam, Yes, ilirmak, and Kizilirmak rivers are investigated. Solar energy potential values are used as the current sources for simulating their renewable energy hydrogen production values. According to the results, higher hydrogen production rates are obtained from the Marmara and Lake Van regions. It is concluded that the hydrogen production potential is highly dependent on the pH values of the water source and the salinity rate of seawater that is descending from the Mediterranean Sea to the Black Sea region. Besides, solar radiation, sunshine duration, and water temperature are the other essential factors. Moreover, Mediterranean Sea water (Icomma el-Anamur) has about 23% higher hydrogen production than Lake Van and has the most increased hydrogen production by 80 L m-2 in May and June. (c) 2021 Hydrogen Energy Publications LLC. Published by Elsevier Ltd. All rights reserved.

In this study, the effect of pulse potential on alkaline water electrolysis energy consumption is investigated. A specially designed electrical circuit is used to observe the effect of different duty cycles and frequency values on water electrolysis energy consumption in different concentration values of alkaline solution. The results show that using pulse potential enhances the mass transport of oxygen and hydrogen bubbles due to the pumping effect. This provides less contact with oxygen bubbles to improve corrosion resistance of anode electrodes. Moreover, decreasing mass transfer losses on the electrode surface resulted in a 20-25% lower energy consumption to produce 1 mol of hydrogen in the cell. The optimum frequency for 10% and 50% duty cycle and 10% and 15% concentration are investigated. For 10% duty cycle, the optimum frequency is specified around 140-200 kHz and for 50% duty cycle, it is around 380-400 kHz for all concentration values. (C) 2018 Hydrogen Energy Publications LLC. Published by Elsevier Ltd. All rights reserved.

Alkaline water electrolysis is the easiest methods for hydrogen production because of their simplicity. Although the simplicity is an advantage; reducing the energy consumption and maintaining the durability and the safety of these systems are the main challenges. In this paper, alkaline water electrolysis system, that uses cost effective electrode materials and magnetic field effects are presented. Cost effective electrodes such as high carbon steel, 304 stainless steel, 316L low carbon steel and graphite material are used for the hydrogen production. After the selection of the best electrode pair, effects of magnetic field to hydrogen production and change of current density are investigated for KOH electrolytes in different concentrations (5 wt%, 10 wt% and 15 wt%). According to the experimental observations the direction of the Lorentz Force affects the hydrogen production and current density. When the Lorentz Force is directed upward, it enhances the hydrogen production for 5 wt% and 15 wt% KOH solution by almost 17%. The increase in current density for 5 wt %, 10 wt% and 15 wt% concentration is 19%, 5%, 13%, respectively. Forced convection in the magnetic field enhances the separation of gas bubbles from electrode surface. Downward directed Lorentz Force decreases hydrogen production and current density values significantly. For 5 wt%, 10 wt% and 15 wt% the hydrogen production decreases by 14%, 8%, 7%, respectively. Similarly, current density for downward directed Lorentz Force decreases by 11%, 7%, 4%, respectively. (C) 2017 Hydrogen Energy Publications LLC. Published by Elsevier Ltd. All rights reserved.

The secretion of interleukin (IL)-1 family cytokines is one of the most potent and earliest pro-inflammatory responses triggered by brucellosis. However, the roles of the most recently discovered IL-1 family members, IL-36, IL-37, and IL-38, in the transition into the chronic form of brucellos is remain largely unknown. Therefore, in this study, the roles of IL-36, IL-37, and IL-38 in brucella infections and their effects on the transition from the acute to chronic form of the disease were investigated. Using peripheral blood samples from 40 patients with acute brucellosis, 40 patients with chronic brucellosis, and 40 healthy control subjects, we analysed the serum concentrations of secreted IL-36, IL-37, and IL-38 using ELISA. The findings were confirmed by using RT-qPCR to analyse the mRNA levels of the genes encoding IL-36, IL-37, and IL-38 in peripheral blood mononuclear cells (PBMCs) from 10 randomly selected patients from each of the three groups. Our results showed that serum IL-37 (p 0.001) and IL-38 (p 0.001) concentrations were lower in patients with brucellosis than in the healthy controls. In addition, serum IL-37 and IL-38 concentrations were higher in the chronic patient group than in the acute patient group. The mRNA expression levels of IL-37 and IL1F10, genes that encode IL-38, did not affect serum cytokine secretion levels. This result suggests that the high secretion levels of IL-37 and IL-38 may be related to the progression into the chronic form of brucellosis. Our findings will aid in clarifying the mechanism of the transition of brucellosis from the acute to the chronic form of the disease.

This paper demonstrates thesignificant and positive effect of applying a magnetic field on the performanceof Proton Exchange Membrane Water Electrolysers (PEMWE). A magnetizer and a transparentPEMWE cell are used to observe the effect of the magnetic field at variablewater flow rates on the PEMWE performance. The presence of the magnetic fieldintroduces Lorentz force which results in a significant improvement in theelectrolyser performance. The magnetic flux density is varied between 0 T and0.5 T, while the water flow rate is varied from 100 ml min-1 to 300ml min-1 to study the effect and relationship between the twoparameters and the performance of the PEMWE. Under a 0.5 T magnetic field and300 ml min-1 flow rate, a 33% increase in the cell performance isachieved compared to the conventional operation at the same flow rate. Thepositive effect is explained by the introduction of Lorentz force from themagnetic field to the operating PEMWE. The improvement here is due to therelaxation and pumping effect of the magnetic field on the electrode surfacewhich results in enhancing oxygen bubbles removal and lowering mass transportpolarisation. Moreover, the enhanced oxygen bubbles removal is expected toincrease the lifetime of the electrolyser as a result of the reduced contact betweenthe produced oxygen and the anode materials.

In this paper, environmental effects of three medium scale (330 kW, 500 kW, 810 kW) and two large scale (2050 kW, 3020 kW) wind turbines with the hub heights of 50 m, 80 m and 100 m installed in Pinarbasi-Kayseri are compared using life cycle assessment methodology. Manufacturing and utilization of wind turbines, decommissioning and recycling steps are considered for this study. GaBi4 life cycle assessment software is utilized for analysis. Selected wind turbines are compared in terms of environmental impacts, embodied energies and energy payback times. The results show that environmental impacts are low for the turbines with high hub heights due to increase in electricity production of those turbines. Wind turbine with rated power of 2050 kW at 100 m hub height is the ideal option to install in Pinarbasi-Kayseri among the selected wind turbines with respect to the energy, environmental aspects and energy payback time. (C) 2013 Elsevier Ltd. All rights reserved.

This study presents the hydrogen production and fissile breeding potentials of Force-Free Helical Reactor (FFHR) fueled with the molten-salt mixtures. The sulfur-iodine (S-I) thermochemical water-splitting and high-temperature electrolysis cycles, which are the most promising water-splitting cycles, are selected to produce large-scale and pure hydrogen. The XSDRNPM/SCALE4.4a neutron transport code is used for the neutronic calculations. The analyses have been performed individually for four different molten-salt mixtures, (pure FLiBe, mixture of FLiBe and ThF(4), mixture of FLiBe and UF(4), and mixture of FLiBe, ThF(4) and (233)UF(4)). The numerical results bring out that the considered molten-salt fusion breeder reactor has a high neutronic performance and can produce a considerable amount of the hydrogen production (up to 40 kg/s), as well as the fissile fuel (up to 2.5 tons/yr). (C) 2010 Professor T. Nejat Veziroglu. Published by Elsevier Ltd. All rights reserved.

The purpose of this follow-up study was to investigate the long-term effects of tonsillectomy in comparison with their short-term results.We successfully retrieved 20 out of our previously reported 37 patients who underwent tonsillectomy in our clinic 54 months ago. The blood levels of CD3+, CD4+, CD8+, CD19+, CD25+ and CD16++56+ (cellular immunity), and IgG, IgA, IgM, C3 and C4 (humoral immunity) were determined and compared with their previously reported short-term respective values.There were no statistically significant differences between the short-term (1 month) and long-term (54 months) values of IgA, IgG, IgM and C4 levels of the patients (P0.05). There was a slight but statistically significant decrease in complement factor C3 value compared to its the early-stage value (P0.05) but this was not significantly different from age-matched healthy controls (P0.05). The levels of CD4+ and CD19+ were higher and the levels of CD16++56+ and CD25+ were lower in the late-stage (54 months) compared to their early-stage values (P0.05). When the long-term immune parameters of the tonsillectomized patients were compared with aged-match healthy controls, there were no significant differences between the levels of immunoglobulins, complements and lymphocytes (IgA, IgG, IgM, C3, C4, CD3+, CD4+, CD8+, CD19+, CD25+, CD16++56+) (P0.05).The results of this long-term follow-up study indicate that tonsillectomy do not compromise the immune functions of children as humoral and cellular immunity of patients recovered compared to their early-stage immune status (1 month), as they have similar immune capacity compared to their age-matched healthy controls at both early- and late-stages. Although a small sample of patients enrolled, our results are of importance with respect to the reassuring in settling the widely held urban myth that tonsillectomy compromises life long immunity.

RESUME Background: It has been reported that abnormalities in the balance of T-helper cells type 1/2 (Th1/Th2) may account for the pathophysiology of human autoimmune diseases. The purpose of this study was to define the role of the Th1/Th2 balance in the pathogenesis of uveitis in Behcet's disease (BD). Methods: From February 2003 to August 2005, we studied 31 patients with active BD. Of these patients, 21 (12 female, 9 male; mean age 35.5 (SD 10) years) presented with acute uveitis, and 10 (7 female, 3 male; mean age 34 (SD 11) years) presented with inflammatory arthritis but no prior uveitis attack.The control group consisted of 10 (7 female, 3 male; mean age 34.7 (SD 8) years) age-matched, healthy individuals. CD4+ CD26+ and CD4+ CD30+ cell surface expression of the peripheral blood CD4+ T lymphocytes was evaluated by analytic flow cytometry in order to determine percentages of Th1 and Th2 lymphocyte subsets. Results: The mean percentage of CD4+ CD26+ and CD4+ CD30+ cells was 26.27 (SD 6.18) % and 2.56 (SD 0.82) %, 17.42 (SD 5.90) % and 2.86 (SD 0.72) %, and 14.99 (SD 3.96) % and 3.11 (SD 1.25) % in BD with active uveitis, BD with inflammatory arthritis but no prior uveitis attack, and control groups, respectively. T-helper 1 (Th1) cell percentage was significantly higher in the BD with active uveitis group than the BD with arthritis and no prior uveitis attack group (p = 0.001). With respect to the percentage of CD30+ Th2 cells, there was no statistical difference between the 2 BD groups (p = 0.529) or among the 3 groups (p = 0.375). Interpretation: Th1 lymphocyte dominance in peripheral circulating blood may play a role in the

This study presents the potential of the burning and/or transmutation (B/T) of transuraniums (TRUs), discharged from the pressured water reactor PWR-UO2 spent fuel, in the modified PROMETHEUS-H fusion reactor. Two different design shapes (Models A and B) were considered. The transmutation zone (TZ), which contains the mixture of TRU nuclides (10%), was located in the modified blankets. The volume fraction of Pu in the mixture is raised from 0 to 40% stepped by 10% to determine its effect on the B/T. The fuel spheres were cladded with SiC (5%) and cooled with high-pressured helium gas (85%) for nuclear heat transfer. The calculations were performed for an operation period (OP) of up to 10 years by 75% plant factor (17) under a neutron wall load (P) of 4.7 MW/m(2). The results bring out that: (1) the Model B transmutes the TRUs more rapidly than the Model A; (2) the effective half-lives decrease about 20 and 40% with the increase of Pu fraction in the cases of Models A and B, respectively; (3) the M values are quite high with respect to the M value of the original PROMETHEUS fusion reactor; (4) the blankets can produce substantial electricity in situ. (c) 2006 Elsevier B.V. All rights reserved.