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Natthaporn Thaweelap Puttimate Thongtan Chongsutthamani Sitthiwet Sophida Thiangviriya Priew Eiamlamai Rapee Utke 《International Journal of Hydrogen Energy》2017,42(39):24915-24926
De/rehydrogenation kinetics and reversibility of MgH2 are improved by doping with activated carbon nanofibers (ACNF) and compositing with LiBH4. Via doping with 5 wt % ACNF, hydrogen absorption of Mg to MgH2 (T = 320 °C and p(H2) = 50 bar) increases from 0.3 to 4.5 wt % H2. Significant reduction of onset dehydrogenation temperature of MgH2 to 340 °C (ΔT = 70 °C as compared with pristine MgH2) together with 6.8–8.2 wt % H2 can be obtained by compositing Mg-5 wt. % ACNF with LiBH4 (LiBH4:Mg mole ratios of 0.5:1, 1:1, and 2:1). During dehydrogenation of Mg-rich composites (0.5:1 and 1:1 mol ratios), the formation of MgB2 and Mg0.816Li0.184 implying the reaction between LiBH4 and MgH2 favors kinetic properties and reversibility, while the composite with 2:1 mol ratio shows individual dehydrogenation of LiBH4 and MgH2. For up-scaling to hydrogen storage tank (~120 times greater sample weight than laboratory scale) of the most suitable composite (1:1 mol ratio), de/rehydrogenation kinetics and hydrogen content released at all positions of the tank are comparable and approach to those from laboratory scale. Due to high purity (100%) and temperature of hydrogen gas from hydride tank, the performance of single proton exchange membrane fuel cell enhances up to 30% with respect to the results from compressed gas tank. 相似文献
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Puttimate Thongtan Palmarin Dansirima Sophida Thiangviriya Natthaporn Thaweelap Apirak Suthummapiwat Praphatsorn Plerdsranoy Rapee Utke 《International Journal of Hydrogen Energy》2018,43(27):12260-12270
By doping with 5 wt % TiF4 and activated carbon (AC), onset and main dehydrogenation temperatures of MgH2 significantly reduce (ΔT = 138 and 109 °C, respectively) with hydrogen capacity of 4.4 wt % H2. Up-scaling to storage tank begins with packing volume and sample weight of 28.8 mL and ~14.5 g, respectively, and continues to 92.6 mL and ~60.5–67 g, respectively. Detailed hydrogen sorption mechanisms and kinetics of the tank tightly packed with four beds of MgH2TiF4-AC (~60.5 g) are investigated. De/rehydrogenation mechanisms are detected by three temperature sensors located at different positions along the tank radius, while hydrogen permeability is benefited by stainless steel mesh sheets and tube inserted in the hydride beds. Fast desorption kinetics of MgH2TiF4-AC tank at ~275–283 °C, approaching to onset dehydrogenation temperature of the powder sample (272 °C) suggests comparable performances of laboratory and tank scales. Hydrogen desorption (T = 300 °C and P(H2) = 1 bar) and absorption (T = 250 °C and P(H2) = 10–15 bar) of MgH2TiF4-AC tank provide gravimetric and volumetric capacities during the 1st-2nd cycles of 4.46 wt % H2 and 28 gH2/L, respectively, while those during the 3rd-15th cycles are up to 3.62 wt % H2 and 23 gH2/L, respectively. Due to homogeneous heat transfer along the tank radius, de/rehydrogenation kinetics superior at the tank center and degrading forward the tank wall can be due to poor hydrogen permeability. Particle sintering and/or agglomeration upon cycling yield deficient hydrogen content reproduced. 相似文献
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Sophida Phuthong Cynthia Guadalupe Reyes-Hernndez Pilar Rodríguez-Rodríguez David Ramiro-Cortijo Marta Gil-Ortega Raquel Gonzlez-Blzquez M. Carmen Gonzlez Angel Luis Lpez de Pablo Silvia M. Arribas 《International journal of molecular sciences》2021,22(1)
Fetal undernutrition programs cardiometabolic diseases, with higher susceptibility in males. The mechanisms implicated are not fully understood and may be related to sex differences in placental adaptation. To evaluate this hypothesis, we investigated placental oxidative balance, vascularization, glucocorticoid barrier, and fetal growth in rats exposed to 50% global nutrient restriction from gestation day 11 (MUN, n = 8) and controls (n = 8). At gestation day 20 (G20), we analyzed maternal, placental, and fetal weights; oxidative damage, antioxidants, corticosterone, and PlGF (placental growth factor, spectrophotometry); and VEGF (vascular endothelial growth factor), 11β-HSD2, p22phox, XO, SOD1, SOD2, SOD3, catalase, and UCP2 expression (Western blot). Compared with controls, MUN dams exhibited lower weight and plasma proteins and higher corticosterone and catalase without oxidative damage. Control male fetuses were larger than female fetuses. MUN males had higher plasma corticosterone and were smaller than control males, but had similar weight than MUN females. MUN male placenta showed higher XO and lower 11β-HSD2, VEGF, SOD2, catalase, UCP2, and feto-placental ratio than controls. MUN females had similar feto-placental ratio and plasma corticosterone than controls. Female placenta expressed lower XO, 11β-HSD2, and SOD3; similar VEGF, SOD1, SOD2, and UCP2; and higher catalase than controls, being 11β-HSD2 and VEGF higher compared to MUN males. Male placenta has worse adaptation to undernutrition with lower efficiency, associated with oxidative disbalance and reduced vascularization and glucocorticoid barrier. Glucocorticoids and low nutrients may both contribute to programming in MUN males. 相似文献
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Effective nanoconfinement of 2LiBH4–MgH2 via simply MgH2 premilling for reversible hydrogen storages
Rapee Gosalawit–Utke Sophida Thiangviriya Payam Javadian Daniel Laipple Claudio Pistidda Nils Bergemann Christian Horstmann Torben R. Jensen Thomas Klassen Martin Dornheim 《International Journal of Hydrogen Energy》2014
To improve nanoconfinement of LiBH4 and MgH2 in carbon aerogel scaffold (CAS), particle size reduction of MgH2 by premilling technique before melt infiltration is proposed. MgH2 is premilled for 5 h prior to milling with LiBH4 and nanoconfinement in CAS to obtained nanoconfined 2LiBH4–premilled MgH2. Significant confinement of both LiBH4 and MgH2 in CAS, confirmed by SEM–EDS–mapping results, is achieved due to MgH2 premilling. Due to effective nanoconfinement, enhancement of CAS:hydride composite weight ratio to 1:1, resulting in increase of hydrogen storage capacity, is possible. Nanoconfined 2LiBH4–premilled MgH2 reveals a single–step dehydrogenation at 345 °C with no B2H6 release, while dehydrogenation of nanoconfined sample without MgH2 premilling performs in multiple steps at elevated temperatures (up to 430 °C) together with considerable amount of B2H6 release. Activation energy (EA) for the main dehydrogenation of nanoconfined 2LiBH4–premilled MgH2 is considerably lower than those of LiBH4 and MgH2 of bulk 2LiBH4–MgH2 (ΔEA = 31.9 and 55.8 kJ/mol with respect to LiBH4 and MgH2, respectively). Approximately twice faster dehydrogenation rate are accomplished after MgH2 premilling. Three hydrogen release (T = 320 °C, P(H2) = 3–4 bar) and uptake (T = 320–325 °C, P(H2) = 84 bar) cycles of nanoconfined 2LiBH4–premilled MgH2 reveal up to 4.96 wt. % H2 (10 wt. % H2 with respect to hydride composite content), while the 1st desorption of nanoconfined sample without MgH2 premilling gives 4.30 wt. % of combined B2H6 and H2 gases. It should be remarked that not only kinetic improvement and B2H6 suppression are obtained by MgH2 premilling, but also the lowest dehydrogenation temperature (T = 320 °C) among other modified 2LiBH4–MgH2 systems is acquired. 相似文献
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