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排序方式: 共有660条查询结果,搜索用时 15 毫秒
1.
SeyedHosein Payandeh Daniel Rentsch Zbigniew Łodziana Ryo Asakura Laurent Bigler Radovan Černý Corsin Battaglia Arndt Remhof 《Advanced functional materials》2021,31(18):2010046
Hydroborate-based solid electrolytes have recently been successfully employed in high voltage, room temperature all-solid-state sodium batteries. The transfer to analogous lithium systems has failed up to now due to the lower conductivity of the corresponding lithium compounds and their high cost. Here LiB11H14 nido-hydroborate as a cost-effective building block and its high-purity synthesis is introduced. The crystal structures of anhydrous LiB11H14 as well as of LiB11H14-based mixed-anion solid electrolytes are solved and high ionic conductivities of 1.1 × 10−4 S cm−1 for Li2(B11H14)(CB11H12) and 1.1 × 10−3 S cm−1 for Li3(B11H14)(CB9H10)2 are obtained, respectively. LiB11H14 exhibits an oxidative stability limit of 2.6 V versus Li+/Li and the proposed decomposition products are discussed based on density functional theory calculations. Strategies are discussed to improve the stability of these compounds by modifying the chemical structure of the nido-hydroborate cage. Galvanostatic cycling in symmetric cells with two lithium metal electrodes shows a small overpotential increase from 22.5 to 30 mV after 620 h (up to 0.5 mAh cm−2), demonstrating that the electrolyte is compatible with metallic anodes. Finally, the Li2(B11H14)(CB11H12) electrolyte is employed in a proof-of-concept half cell with a TiS2 cathode with a capacity retention of 82% after 150 cycles at C/5. 相似文献
2.
Kasper T. Møller Mathias Jørgensen Jacob G. Andreasen Jørgen Skibsted Zbigniew Łodziana Yaroslav Filinchuk Torben R. Jensen 《International Journal of Hydrogen Energy》2018,43(1):311-321
A new potassium tetraamidoboranealuminate, K[Al(NH2BH3)4], has been synthesized by a mechanochemical reaction between KAlH4 and NH3BH3. The compound, K[Al(NH2BH3)4], crystallizes in a triclinic unit cell with space group symmetry P?1. The crystal structure consists of [K(NH2BH3)6]5? octahedra which facilitate the bridging between K+ in 1D chains, while also bridging K+ to Al3+ to connect the 1D chains in a 3D network. Thermal analysis reveals that K[Al(NH2BH3)4] decomposes in two exothermic steps at T ~ 94 and 138 °C and releases primarily hydrogen. The total gas release amounts to ~6.0 wt% H2. The decomposition products are investigated ex situ by powder X-ray diffraction, infrared spectroscopy, and 11B and 27Al NMR and identified as KBH4 and amorphous phases, possibly BN3, N2BH, and/or NBH2 whereas aluminum is found in four-, five-, and six-fold coordination. Unfortunately, the decomposed sample shows no hydrogen absorption at T = 260 °C and p(H2) = 110 bar. 相似文献
3.
This article presents a method of filtering thermal images by means of approximation using cubic B-spline patch surfaces. Approximation uses chord length parameterization with non-uniform distribution of knots, depending on the change rate of pixel values in rows and columns of the image. Advantages of approximation with such parameterization are compared with popular uniform parameterization. Presented method is very versatile and can be used for example in 3D surface topography of objects tested with stereoscopic microscopes, in resolution change of arbitrary images or modeling processes depending on two parameters. Filtering results are presented using plugin for the Soft4Image program, which was designed to unify different digital signal processing algorithms. 相似文献
4.
5.
Marta Izabela Jonas Alina Kurylowicz Zbigniew Bartoszewicz Wojciech Lisik Maurycy Jonas Zbigniew Wierzbicki Andrzej Chmura Piotr Pruszczyk Monika Puzianowska-Kuznicka 《International journal of molecular sciences》2015,16(10):25817-25830
Excess adiposity is associated with chronic inflammation, which takes part in the development of obesity-related complications. The aim of this study was to establish whether subcutaneous (SAT) or visceral (VAT) adipose tissue plays a major role in synthesis of pro-inflammatory cytokines. Concentrations of interleukins (IL): 1β, 6, 8 and 15 were measured at the protein level by an ELISA-based method and on the mRNA level by real-time PCR in VAT and SAT samples obtained from 49 obese (BMI > 40 kg/m2) and 16 normal-weight (BMI 20–24.9 kg/m2) controls. IL-6 and IL-15 protein concentrations were higher in SAT than in VAT for both obese (p = 0.003 and p < 0.0001, respectively) and control individuals (p = 0.004 and p = 0.001, respectively), while for IL-1β this was observed only in obese subjects (p = 0.047). What characterized obese individuals was the higher expression of IL-6 and IL-15 at the protein level in VAT compared to normal-weight controls (p = 0.047 and p = 0.016, respectively). Additionally, obese individuals with metabolic syndrome had higher IL-1β levels in VAT than did obese individuals without this syndrome (p = 0.003). In conclusion, concentrations of some pro-inflammatory cytokines were higher in SAT than in VAT, but it was the increased pro-inflammatory activity of VAT that was associated with obesity and metabolic syndrome. 相似文献
6.
7.
Zbigniew Lewandowski 《Water research》1985,19(5):589-596
The effect of chromium Cr6+ on bacterial denitrification was investigated. The long-term influence of chromium presence was observed in packed bed reactors using methanol, ethanol, n-propanol, n-butanol, sec-butanol, tert-butanol, iso-butanol and n-pentanol as the carbon and energy sources for denitrifiers. Short-term influence was investigated by the inhibition coefficient Ki determination within activated sludge under anoxic conditions. The measured inhibition constant Ki was equal to 84.2 mg l?1 Cr6+, independently of the kind of organic compound utilized as the electron donor for the bacterial system. The concepts of the reactor resistance to inhibition (RRI) and the resistance to inhibition (RI) have been evaluated. 相似文献
8.
We have evaluated the effects of selected minerals present in subsoil environment on the efficiency of lead removal from contaminated groundwaters using biofilms composed of sulfate-reducing microorganisms, and examined the stability of metal deposits after the biofilms had been temporarily exposed to the air. To quantify the studied effects, lead was immobilized in biofilms of Desulfovibrio desulfuricans grown anaerobically in two flat-plate flow reactors, one filled with hematite and the other with quartz. While the biofilms in both reactors were heterogeneous and consisted of voids and channels, the biofilms grown on hematite were denser, thicker, and more porous than those grown on quartz. The average H2S concentrations, measured using microelectrodes, were higher in the biofilms grown on quartz than those measured in the biofilms grown on hematite. During 18 weeks of operation, iron was continuously released from the hematite. Lead was immobilized more efficiently in the biofilms grown on quartz than it was in the biofilms grown on hematite. Lead deposits were partially reoxidized, especially in biofilms grown on hematite, and the biofilms in both reactors responded to the presence of oxygen by lowering their density and increasing the H2S production rate. 相似文献
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10.
Jerzy Jedlinski Jean Luc Grosseau Poussard Jarosław Dabek Kazimierz Kowalski Marek Nocun Grzegorz Smola Zbigniew Żurek 《Oxidation of Metals》2017,88(3-4):371-382
The very early stages of the oxidation of an Fe20Cr2Al alloy, unmodified and ion-implanted by aluminium, yttrium and a combination of both elements, Al and Y, were studied at 1100 °C in oxygen using two-stage-oxidation exposures with 18O2 as a tracer and subsequent characterisation of the scales using SIMS analyses of distribution of oxygen isotopes and oxide-related negative ion clusters, SEM observations of the surface morphology and photoluminescence spectroscopy analysis of the phase composition. The scales formed in all cases, except for the Al-implanted alloy, exhibited layered structures, with the outer part comprising Fe- and Cr-rich oxide, and the inner part being Al2O3, which grew due to a mixed outward–inward mechanism . The alumina sub-layers contained the transient oxides and α-Al2O3. Implanted Al significantly affected the mechanism of the scale growth, providing that the scale consisted essentially of α-Al2O3, and grew via a mixed inward-outward mechanism typical for scales on alumina formers. 相似文献