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71.
Dheeraj Kumar Singh Till Fuchs Christian Krempaszky Boris Mogwitz Simon Burkhardt Felix H. Richter Jürgen Janek 《Advanced functional materials》2023,33(1):2211067
Enabling the lithium metal anode (LMA) in solid-state batteries (SSBs) is the key to developing high energy density battery technologies. However, maintaining a stable electrode–electrolyte interface presents a critical challenge to high cycling rate and prolonged cycle life. One such issue is the interfacial pore formation in LMA during stripping. To overcome this, either higher stack pressure or binary lithium alloy anodes are used. Herein, it is shown that fine-grained (d = 20 µm) polycrystalline LMA can avoid pore formation by exploiting the microstructural dependence of the creep rates. In a symmetric cell set-up, i.e., LiǀLi6.25Al0.25La3Zr2O12(LLZO)ǀLi, fine-grained LMA achieves > 11.0 mAh cm−2 compared to ≈ 3.6 mAh cm−2 for coarse-grained LMA (d = 295 µm) at 0.1 mA cm−2 and at moderate stress of 2.0 MPa. Smaller diffusion lengths (≈ 20 µm) and higher diffusivity pathway along dislocations (Dd ≈ 10−7 cm2 s−1), generated during cell fabrication, result in enhanced viscoplastic deformation in fine-grained polycrystalline LMA. The electrochemical performances corroborate well with estimated creep rates. Thus, microstructural control of LMA can significantly reduce the required stack pressure during stripping. These results are particularly relevant for “anode-free” SSBs wherein both the microstructure and the mechanical state of the lithium are critical parameters. 相似文献
72.
Boris Krasovitski 《The Journal of Adhesion》2013,89(7-8):869-880
The adhesion of spheroidal particles to spherical drops is calculated and discussed in terms of an equilibrium-penetration index. The present study emphasizes the case of particles that are sufficiently large to affect the drop volume upon penetration. It is shown that the more elongated the particles, the steeper the dependence of the penetration index on the contact angle. The effect of line tension on nanoscale particles is considered. Positive line tensions increase the steepness of the dependence of penetration index on contact angle whereas negative line tensions decrease this dependence. In addition, the energy barrier caused by positive line tensions is presented and discussed. 相似文献
73.
Dr. Alessia Amore Kim Wals Evelyn Koekoek Rieuwert Hoppes Mireille Toebes Prof. Ton N. M. Schumacher Dr. Boris Rodenko Prof. Huib Ovaa 《Chembiochem : a European journal of chemical biology》2013,14(1):123-131
Incorporation of cleavable linkers into peptides and proteins is of particular value in the study of biological processes. Here we describe the synthesis of a cleavable linker that is hypersensitive to oxidative cleavage as the result of the periodate reactivity of a vicinal amino alcohol moiety. Two strategies directed towards the synthesis of a building block suitable for solid‐phase peptide synthesis were developed: a chemoenzymatic route, involving L ‐threonine aldolase, and an enantioselective chemical route; these led to α,γ‐diamino‐β‐hydroxybutanoic acids in diastereoisomerically mixed and enantiopure forms, respectively. Incorporation of the 1,2‐amino alcohol linker into the backbone of a peptide generated a conditional peptide that was rapidly cleaved at very low concentrations of sodium periodate. This cleavable peptide ligand was applied in the generation of MHC exchange reagents for the detection of antigen‐specific T cells in peripheral blood cells. The extremely low concentration of periodate required to trigger MHC peptide exchange allowed the co‐oxidation of methionine and disulfide residues to be avoided. Conditional MHC reagents hypersensitive to periodate can now be applied without limitations when UV irradiation is undesired or less practical. 相似文献
74.
Increasing Productivity through Integrated Production Engineering and Processing Expertise The future of production engineering is interdisciplinary. Between product innovation and product marketing there lies a design process which has to be optimised and which is interdisciplinary in character. The design process has to satisfy the demands of global markets on chemical products, which lead, for example, to shorter and shorter product life cycles, and to demands for low production costs, high and consistent product quality, and faster market launches. 相似文献
75.
Rafael Davalos Yong Huang Boris Rubinsky 《Nanoscale and Microscale Thermophysical Engineering》2013,17(3):147-159
This article provides a brief review of the field of electroporation and introduces a new microdevice that facilitates studies to test theories, gain understanding, and control this important biomedical technology. Electroporation, a bio-electrochemical process whose fundamentals are not yet understood, is a means of permeating the cell membrane by applying a voltage across the cell and forming nano-scale pores in the membrane. It has become an important field in biotechnology and medicine for the controlled introduction of macromolecules, such as gene constructs and drugs, into various cells. It is viewed as an engineering alternative to biological techniques for the genetic engineering of cells. To study and control electroporation, we have created a low-cost microelectroporation chip that incorporates a live biological cell with an electric circuit. The device revealed an important behavior of cells in electrical fields. They produce measurable electrical information about the electroporation state of the cell that may enable precise control of the process. The device can be used to facilitate fundamental studies of electroporation and can become useful in providing precise control over biotechnological processes. 相似文献
76.
Boris Levy 《Journal of Electroceramics》1997,1(3):239-272
A number of major disciplines have separately developed as distinctfields of energy research utilizing nanostructure materials: i.Heterogeneous photocatalysis; ii. Photoelectrochemistry—includingelectrochemical photovoltaic cells; iii. Photochemistry in zeolites andintercalated materials; iv. Photochemistry of thin films andmembranes—including self assembled structures; and v. Supramolecularphotochemistry. Photophysical properties of small particles, in the angstromto nanosized regime—depending on specific material, resulting in bandgap broadening as compared to bulk properties, and corresponding phenomenawith organic dyes as a function of aggregate size having relevance to energyrelated applications are discussed, as are dielectric confinement effectscontrolling the geometric distribution of light absorption within aparticle, aggregate or adsorbed molecular deposit. Synergism among fieldshas emerged, as for example with transition metal oxide photocatalysts andphotoelectrodes, combined with supramolecular spectral sensitizingtransition metal ligand complexes used to harvest light and vectoriallytransfer photo-generated electrons and holes along selected energeticpathways. Two systems have already demonstrated potential for significantlyreducing reliance on fossil fuels and concomitant environmental stress.These are: i. Pollution remediation with wide band gap semiconductingparticulate and nanoporous photocatalysts; and ii. Electrochemicalphotovoltaic cells utilizing nanoporous semiconducting electrodes fabricatedby lightly sintering nanosized TiOÄ2É particulates, followed byspectral sensitization with tri-nuclear ruthenium ligand dyes.Heterojunction contacts between inorganic photoconducting particulates,termed photocatalytic diodes, and three phase systems, termed photocatalytictransistors, have been demonstrated to increase photocatalytic conversionefficiency in catalytic processes and to increase light sensitivity ofanalogous silver halide photographic systems. Research being carried out inlaboratories throughout the world, aimed at improving the efficiency andunderstanding of the multi-disciplinary processes involved are described.Suggested areas of investigation for achievement of short (5 years) andlong term (5–20 years) goals are reviewed. 相似文献
77.
78.
文章阐述了几种组合互感器的特点,介绍了组合互感器的误差特性。较详细地介绍了由1台倒立式电流互感器和1台具有开放式铁心的电磁式电压互感器组合而成的新型高压组合互感器(VAU型)的基本特征及主要性能,测量结果表明,VAU型组合互感器误差特性好,瓷套管上电场强度沿高度分布均匀,体积小,占空间少,制造成本低,而且还可防铁磁谐振,现在的最高设备电压已达550kV。 相似文献
79.
A weak diblock polyampholyte PMAA-b-PDMAEMA, poly(methacrylic acid)-block-poly((dimethylamino)ethyl methacrylate), was investigated as a model system for the influence of an acid-base-equilibrium
of a phthalic acid buffer system on the polyelectrolyte adsorption behaviour. The adsorption of polyampholyte from aqueous
solution onto silicon surfaces is known to be strongly influenced by the parameters of the polymer solution and the properties
of the polyampholyte itself like block ratio or molecular weight. In the case of the investigated polyampholytes, the main
parameter with the most significant influence on the adsorption is the pH. The big influence of pH on adsorption results from
the charges of the polymer chains and the substrate, which are determined by the pH. Therefore, it should be useful to investigate
the influence of a buffer system on the polyampholyte adsorption. On the one hand the buffer system enables to determine the
pH of the aqueous polyampholyte solution more precisely. On the other hand the concentrations of different phthalic species
like the phthalic acid, the hydrogen phthalate and the phthalate are strongly influenced by pH. These different species were
observed to have a strong influence on the adsorption behaviour of the polyampholyte, so the adsorption as function of pH
was observed to be also determined by the acid-base-equilibrium of the buffer system. The adsorbed amount of polyampholyte
dried after the adsorption process was determined using ellipsometry, while the surface topography of these adsorbed layers
were characterized by atomic force microscopy (AFM).
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
80.
Vladimir N. Losev Elena V. Borodina Alexander S. Samoilo Anatoly M. Zhyzhaev Boris A. Velichko 《分离科学与技术》2018,53(11):1654-1665
Pine sawdust and malt sprouts modified with orthophosphoric acid and carbamide have been proposed for solid-phase extraction (SPE) of nonferrous, heavy, and precious metals and their subsequent determination in the environmental samples by inductively coupled plasma optical emission spectrometry (ICP-OES). Modified adsorbents were characterized by SEM, TGA, and FT-IR and compared with native matrixes. SPE of some nonferrous and precious metal ions by biosorbents was studied. Depending on the SPE conditions, it was possible to separate nonferrous and heavy metals from alkali and alkaline earth metals. The proposed adsorbents are effective for preconcentration of nonferrous and heavy metals from natural waters and precious metals from solutions after digestion of geological samples. 相似文献