The surface layer and elemental composition of a lithium-metal electrode before and after in contact with nanocomposite polymer electrolytes (NcPEs) comprising poly(ethylene oxide)/ca3(PO4)2/LiX (X = N(cF3SO2)2, clO4)...
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The surface layer and elemental composition of a lithium-metal electrode before and after in contact with nanocomposite polymer electrolytes (NcPEs) comprising poly(ethylene oxide)/ca3(PO4)2/LiX (X = N(cF3SO2)2, clO4) were analyzed by X-ray photoelectron spectroscopy. The presence of Li2cO3/LiOH in the outer layer of the native film was identified. The formation of LiF was detected on lithium surface when in contact with NcPE containing LiN(cF3SO2)2 and is attributed to the reaction between the native film and impurities. Li/NcPE/Li symmetriccells were assembled, and the thickness of the solid electrolyte interface as a function of time was analyzed at 60 degrees c. (c) 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2012
Systems code is almost universally written in the c programming language or a variant. c has a very low level of type and memory abstraction and formal reasoning about c systems code requires a memory model that is ab...
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Systems code is almost universally written in the c programming language or a variant. c has a very low level of type and memory abstraction and formal reasoning about c systems code requires a memory model that is able to capture the semantics of c pointers and types. At the same time, proof-based verification demands abstraction, in particular from the aliasing and frame problems. In this paper we present a study in the mechanisation of two proof abstractions for pointer program verification in the Isabelle/HOL theorem prover, based on a low-level memory model for c. The language's type system presents challenges for the multiple independent typed heaps (Burstall-Bornat) and separation logic proof techniques. In addition to issues arising from explicit value size/alignment, padding, type-unsafe casts and pointer address arithmetic, structured types such as c's arrays and structs are problematic due to the non-monotonic nature of pointer and lvalue validity in the presence of the unary &-operator. For example, type-safe updates through pointers to fields of a struct break the independence of updates across typed heaps or a (*)-conjuncts. We provide models and rules that are able to cope with these language features and types, eschewing common over-simplifications and utilising expressive shallow embeddings in higher-order logic. Two case studies are provided that demonstrate the applicability of the mechanised models to real-world systems code;a working of the standard in-place list reversal example and an overview of the verification of the L4 microkernel's memory allocator.
Superior electrode materials play a key role on the electrochemical performance for the lithium-ion batteries and supercapacitors. The co3O4-based materials are promising electrode materials due to their high specific...
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Superior electrode materials play a key role on the electrochemical performance for the lithium-ion batteries and supercapacitors. The co3O4-based materials are promising electrode materials due to their high specificcapacity and energy density. However, the poor cycle performance limits their applications during the process of the commercialization for the lithium-ion batteries and supercapacitors. Because of the poor cycle stability, c, N co-doped co3O4 hollow spheres are successfully prepared and used as electrode materials for the lithium-ion batteries and supercapacitors. Via the c, N co-doping process, the electronicconductivity is greatly improved. Moreover, the hollow structure could ensure the structural stability during the electrochemical process. As a result, the cycle performance and specificcapacity are greatly improved when the c, N co-doped co3O4 composites are used as electrode materials for the lithium-ion batteries and supercapacitors. (c) 2019 Hydrogen Energy Publications LLc. Published by Elsevier Ltd. All rights reserved.
corynebacterium glutamicum is the major workhorse for the microbial production of several amino and organic acids. As long as these derive from tricarboxylic acid cycle intermediates, the activity of anaplerotic react...
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corynebacterium glutamicum is the major workhorse for the microbial production of several amino and organic acids. As long as these derive from tricarboxylic acid cycle intermediates, the activity of anaplerotic reactions is pivotal for a high biosynthetic yield. To determine single anaplerotic activities c-13-Metabolic Flux Analysis (c-13-MFA) has been extensively used for c. glutamicum, however with different network topologies, inconsistent or poorly determined anaplerotic reaction rates. Therefore, in this study we set out to investigate whether a focused isotopomer model of the anaplerotic node can at all admit a unique solution for all fluxes. By analyzing different scenarios of active anaplerotic reactions, we show in full generality that for c. glutamicum only certain anaplerotic deletion mutants allow to uniquely determine the anaplerotic fluxes from c-13-isotopomer data. We stress that the result of this analysis for different assumptions on active enzymes is directly transferable to other compartment-free organisms. Our results demonstrate that there exist biologically relevant metabolic network topologies for which the flux distribution cannot be inferred by classical c-13-MFA. Biotechnol. Bioeng. 2016;113: 661-674. (c) 2015 Wiley Periodicals, Inc.
OpencL is an open standard for parallel programming of heterogeneous compute devices, such as GPUs, cPUs, DSPs or FPGAs. However, the verbosity of its c host API can hinder application development. In this paper we pr...
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OpencL is an open standard for parallel programming of heterogeneous compute devices, such as GPUs, cPUs, DSPs or FPGAs. However, the verbosity of its c host API can hinder application development. In this paper we present cf4ocl, a software library for rapid development of OpencL programs in pure c. It aims to reduce the verbosity of the OpencL API, offering straightforward memory management, integrated profiling of events (e.g., kernel execution and data transfers), simple but extensible device selection mechanism and user-friendly error management. We compare two versions of a conceptual application example, one based on cf4ocl, the other developed directly with the OpencL host API. Results show that the former is simpler to implement and offers more features, at the cost of an effectively negligible computational overhead. Additionally, the tools provided with cf4ocl allowed for a quick analysis on how to optimize the application. (c) 2017 Elsevier B.V. All rights reserved.
We address the problem of estimating the carrier-to-noise ratio (c/N-0) in weak signal conditions. There are several environments, such as forested areas, indoor buildings and urban canyons, where high-sensitivity glo...
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We address the problem of estimating the carrier-to-noise ratio (c/N-0) in weak signal conditions. There are several environments, such as forested areas, indoor buildings and urban canyons, where high-sensitivity global navigation satellite system (HS-GNSS) receivers are expected to work under these reception conditions. The acquisition of weak signals from the satellites requires the use of post-detection integration (PDI) techniques to accumulate enough energy to detect them. However, due to the attenuation suffered by these signals, estimating their c/N-0 becomes a challenge. Measurements of c/N-0 are important in many applications of HS-GNSS receivers such as the determination of a detection threshold or the mitigation of near-far problems. For this reason, different techniques have been proposed in the literature to estimate the c/N-0, but they only work properly in the high c/N-0 region where the coherent integration is enough to acquire the satellites. We derive four c/N-0 estimators that are specially designed for HS-GNSS snapshot receivers and only use the output of a PDI technique to perform the estimation. We consider four PDI techniques, namely non-coherent PDI, non-quadratic non-coherent PDI, differential PDI and truncated generalized PDI and we obtain the corresponding c/N-0 estimator for each of them. Our performance analysis shows a significant advantage of the proposed estimators with respect to other c/N-0 estimators available in the literature in terms of estimation accuracy and computational resources.
Monodispersed c, Ag co-modified TiO2 microspheres were successfully synthesized through a two-step method. Firstly, monodisperse spherical TiO2 particles were obtained via controlled hydrolysis of TBOT (tetrabutyltita...
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Monodispersed c, Ag co-modified TiO2 microspheres were successfully synthesized through a two-step method. Firstly, monodisperse spherical TiO2 particles were obtained via controlled hydrolysis of TBOT (tetrabutyltitanate) in ethanol. Secondly, the c, Ag co-modified TiO2 microspheres were prepared through a simple calcination process, in which the AgNO3 and citric acid was used as Ag and c source, respectively. The physical and chemical properties of c, Ag co-modified TiO2 microspheres were carefully studied by using XRD, SEM, TEM, Raman, PL spectra and UV-vis diffuse reflectance spectra (DRS), while the chemical states of c and Ag were discussed via EDS (energy dispersive spectrometer) and XPS. The photocatalytic activity of the as-prepared products was evaluated by photocatalytic decolorization of Rhodamine B (Rh B) aqueous solution at ambient temperature under UV and visible-light irradiation. The photocatalytic activity research shows that, with the cooperation of two modified materials, c, Ag co-modified TiO2 microspheres exhibit enhanced photocatalytic activity both in ultraviolet and visible-light region compared with that of pure TiO2 and single Ag modified TiO2 microspheres. (c) 2013 Elsevier B.V. All rights reserved.
An investigation was carried out on the reaction process and mechanism between K 2TiF 6, graphite powder and aluminum melt with the common Ti concentration of 5%～7% in the grain refiner Al Ti c master alloys and the ...
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An investigation was carried out on the reaction process and mechanism between K 2TiF 6, graphite powder and aluminum melt with the common Ti concentration of 5%～7% in the grain refiner Al Ti c master alloys and the reaction temperature of 750～950 ℃, aiming at understanding their reaction mechanism and putting forward the aluminothermal reduction reaction method to practical use. During experimental investigation, K 2TiF 6 and graphite wrapped in aluminum foils were introduced into the aluminum melt at 850 ℃. Samples of alloy and slag were investigated by chemical analysis, XRD examination, SEM observation, and EDS analysis as well. It was found that the reaction was very vigorous at the beginning of the process and then reached a dynamic equilibrium. There were 3 particular reactions during the aluminothermal reaction process. At the beginning stage of the reaction, there emerged the phases of Tic and one type of metastable intermetallic phase TiAl 9 as well as TiAl 3 in aluminum melt. At the late stage of the reaction, the metastable phase TiAl 9 disappeared and another phase of Al 4c 3 emerged.
The physical properties and device electrical properties of superlattice-like c/Sb phase change films are investigated. compared with Sb monolayer films, the superlattice-like c/Sb films have preferable thermal stabil...
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The physical properties and device electrical properties of superlattice-like c/Sb phase change films are investigated. compared with Sb monolayer films, the superlattice-like c/Sb films have preferable thermal stability, including higher crystallization temperature, longer data life, and larger crystallization activation energy. As the thickness of the carbon layer increases, the band gap gradually increases. X-ray photoelectron spectroscopy results show that c-Sb bonds exist in the c/Sb superlattice-like films. X-ray diffraction and atomic force microscope results show that the addition of carbon inhibits the grain growth, making the grain size smaller and inhibiting the crystallization of Sb materials. Phase-change memory devices based on [c(6nm)/Sb(4nm)](8) superlattice-like films have smaller threshold voltages and lower power consumption compared to Sb films. In conclusion, c/Sb superlattice-like films have high thermal stability and low power consumption.
Three novel curcuminoids, curcumaromins A-c (1-3, resp.), along with a known compound, longiferone B (4) were isolated from curcuma aromatica SALISB. The structures of the new compounds were elucidated as (1E,4Z,6E)-5...
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Three novel curcuminoids, curcumaromins A-c (1-3, resp.), along with a known compound, longiferone B (4) were isolated from curcuma aromatica SALISB. The structures of the new compounds were elucidated as (1E,4Z,6E)-5-hydroxy-7-{4-hydroxy-3-[(1R*,6R*)-3-methyl-6-(propan-2-yl) cyclohex- 2-en-1-yl) phenyl}-1-(4-hydroxyphenyl)hepta-1,4,6-trien-3-one (1), 2,3-dihydro-2-(4-hydroxyphenyl)- 6-[(E)-2-(4-hydroxyphenyl) ethenyl]-5-[(1R*, 6R*)-3-methyl-6-(propan-2-yl) cyclohex-2-en-1-yl]-4Hpyran- 4-one (2), and (1E, 6E)-1,7-bis(4-hydroxyphenyl)-4-[(1R*, 6R*)-3-methyl-6-(propan-2-yl) cyclohex- 2-en-1-yl] hepta-1,6-diene-3,5-dione (3) on the basis of spectroscopic analysis. curcumaromins A-c (1-3) represented the first examples of menthane monoterpene-coupled curcuminoids. The known compound, longiferone B (4), was the first daucane sesquiterpene isolated from the genus curcuma.
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