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关键词： Additives   Redox reactions   Kinetic parameters   Electrodes   Voltammetry  

摘要： A theoretical analysis of reversible and quasireversible electrode reactions of a dissolved redox couple under conditions of the novel technique of differential square-wavevoltammetry (DSWV) is presented. The technique is recently introduced as a hybrid form between differential pulse voltammetry(DPV) and square-wave voltammetry (SWV) as the two mostadvanced and competitive pulse-form voltammetric techniques fo ra purpose of unifying their advantages and further advancing both techniques in terms of analytical performances, mechanisticanalysis, and electrode kinetics. The potential modulation of DSWV consists of potential steps and pulses providing a plethora of voltammetric curves, which enable in-depth characterization of the electrode reaction with a minimal set of measurements. Based on numerical simulations, a set of criteria for characterization and differentiation between reversible and quasireversible electrode reactions are established

关键词： Numerical methods  

摘要： Analyzing and predicting diffusion-induced stress are of paramount importance in understanding the structural durability of lithium- and sodium-ion batteries, which generally require solving initial-boundary value problems, involving partial differential equations (PDEs) for mechanical equilibrium and mass transport. Due to the complexity and nonlinear characteristics of the initial-boundary value problems, numerical methods, such as finite difference, finite element, spectral analysis, and so forth, have been used. In this work, we propose two whole loss functions as the sum of the residuals of the PDEs, initial conditions and boundary conditions for the problems with decoupling and coupling between diffusion and stress, respectively, and apply a physics-inspired neural network under the framework of DeepXDE to solve diffusion-induced stress in an elastic sphere in contrast to traditional numerical methods. Using time-space coordinates as inputs and displacement and the solute concentration as outputs of artificial neural networks, we solve the spatiotemporal evolution of the displacement and the solute concentration in the elastic sphere for both the decoupling and coupling problems. The numerical results from the physics-inspired neural network are validated by analytical solutions and a finite element simulation using the COMSOL package. The method developed in this work opens an approach to analyze the stress evolution in electrodes due to electrochemical cycling.

关键词： Common-mode feedback   fully differential op-amp   telescopic first stage   ultra-wideband   V2X  

摘要： In this paper, an ultra-wideband fully differential two-stage telescopic 65-nm CMOS op-amp is presented, which uses low-voltage design techniques such as level shifter circuits and low-voltage cascade current mirrors. The designed op-amp consists of two stages. While the telescopic first stage provides high speed and low swing, the second stage provides high gain and large swing. Common-mode feedback circuits (CMFB), which contain five transistors OTA and sensing resistors, are used to set the first-stage output to a known value. The designed two-stage telescopic operational amplifier has 41.04 dB lower frequency gain, 1.81 GHz gain-bandwidth product (GBW) and 51.9 degrees phase margin under 5 pF load capacitance. The design consumes a total current of 11.9 mA from a 1.2-V supply voltage. Presented fully differential two-stage telescopic op-amp by using low-voltage design techniques is suitable for active filter in vehicle-to-everything (V2X) applications with 120 mu m x 55 mu m layout area.

关键词： affective processing   high-resolution fMRI   olfactory reward   pavlovian instrumental transfer   sensory pleasure   ventral striatum  

摘要： The ventral striatum is implicated in the affective processing of reward, which can be divided into a motivational and a hedonic component. Here, we examined whether these two components rely on distinct neural substrates within the ventral striatum in humans (11 females and 13 males). We used a high-resolution fMRI protocol targeting the ventral striatum com-bined with a pavlovian-instrumental task and a hedonic reactivity task. Both tasks involved an olfactory reward, thereby allowing us to measure pavlovian-triggered motivation and sensory pleasure for the same reward within the same partici -pants. Our findings show that different subregions of the ventral striatum are dissociable in their contributions to the moti-vational versus the hedonic component of the affective processing of reward. Parsing the neural mechanisms of the interplay between pavlovian incentive and hedonic processes may have important implications for understanding compulsive reward-seeking behaviors such as addiction, binge eating, or gambling.

关键词： Silicon wafers  

摘要： The surface recombination velocity (SRV), which reflects the fundamental characteristics of surface defects of semiconductor wafers, is an important parameter in evaluating the quality of surface passivation and electrical performance of surface devices. In conventional photocarrier radiometry (PCR) used for characterizing the electronic transport properties of electronically thick silicon wafers, the rear SRV usually cannot be determined directly due to the relatively low sensitivity of PCR signal to the rear SRV. On the other hand, the determination of front SRV is also very sensitive to the experimental measurement error, especially the measurement error of instrumental frequency response, which is not always easy to be accurately measured in the experiment. In this paper, the front and rear SRVs of silicon wafers are extracted simultaneously with high accuracy by a differential PCR via multi-parameter fitting of the experimental frequency dependences of amplitude ratio and phase difference of PCR signals obtained from the regular measurements and measurements with wafers being flipped respectively to a corresponding differential nonlinear PCR model. The comparison between the front and rear SRVs determined by the conventional and differential PCRs indicates that the differential PCR is highly accurate for the simultaneous determination of the front and rear SRVs of silicon wafers.& nbsp;Published under an exclusive license by AIP Publishing.

关键词： co-culture   cotton   FOV4   Fusarium wilt   Gossypium   in vitro  

摘要： Fusarium oxysporum f. sp. vasinfectum race 4 (FOV4) is a devastating fungus pathogen that causes Fusarium wilt in both domesticated cotton species, Gossypium hirsutum (Upland) and G. barbadense (Pima). Greenhouse and field-based pathogenicity assays can be a challenge because of nonuniform inoculum levels, the presence of endophytes, and varying environmental factors. Therefore, an in vitro coculture system was designed to support the growth of both domesticated cotton species and FOV4 via an inert polyphenolic foam substrate with a liquid medium. A Fusarium wilt-susceptible Pima cotton cultivar, G. barbadense 'GB1031';a highly resistant Pima cotton cultivar, G. barbadense 'DP348RF';and a susceptible Upland cotton cultivar, G. hirsutum 'TM-1', were evaluated for 30 days during coculture with FOV4 in this foam-based system. Thirty days after inoculation, disease symptoms were more severe in both susceptible cultivars, which displayed higher percentages of foliar damage, and greater plant mortality than observed in 'DP348RF', the resistant Pima cotton cultivar. This foam-based in vitro system may be useful for screening cotton germplasm for resistance to a variety of fungus pathogens and may facilitate the study of biotic interactions in domesticated cotton species under controlled environmental conditions.

关键词： intraspecies diversity   symptom expression   virus accumulation   Rdr1 gene  

摘要： Yellow tailflower mild mottle virus (YTMMV, genus Tobamovirus) was identified from wild plants of solanaceous species in Australia. Nicotiana benthamiana is a species indigenous to the arid north of Australia. N. benthamiana accession RA-4 (the lab type), which has a mutant, functionally defective, RNA-dependent RNA polymerase 1 (Rdr1) gene (Nb-Rdr1m), has played a significant role in plant virology, but little study has been done regarding responses to virus infection by other accessions of N. benthamiana. All wild-collected N. benthamiana accessions used in this study harbored wild-type Rdr1 genes (Nb-Rdr1). We compared symptoms of YTMMV infection and viral RNA load on RA-4 and nine wild-collected accessions of N. benthamiana from mainland Western Australia, an island, and the Northern Territory. After inoculation with YTMMV, RA-4 plants responded with systemic hypersensitivity and all individuals were dead 35 days postinoculation (dpi). Plants of wild-collected accessions exhibited a range of symptoms, from mild to severe, and some, but not all, died in the same period. Quantitative reverse transcription PCR revealed that the Rdr1 mutation was not a predictor of viral RNA load or symptom severity. For example, wild-collected A019412 plants carried more than twice the viral RNA load of RA-4 plants, but symptom expression was moderate. For plants of most accessions, viral RNA load did not increase after 10 dpi. The exception was plants of accession Barrow-1, in which viral RNA load was low until 15 dpi, after which it increased more than 29-fold. This study revealed differential responses by N. benthamiana accessions to infection by an isolate of YTMMV. The Rdr1 gene, whether mutant or wild-type, did not appear to influence viral RNA load or disease expression. Genetic diversity of the 10 N. benthamiana accessions in some cases reflected geographical location, but in other accessions this was not so.

关键词： Mathematics & Statistics   MathML  

ISBN: (数字)9781000475357 ISBN: (纸本)9781003216759

摘要： Diffusion Processes, Jump Processes, and Stochastic Differential Equations provides a compact exposition of the results explaining interrelations between diffusion stochastic processes, stochastic differential equations and the fractional infinitesimal operators. The draft of this book has been extensively classroom tested by the author at Case Western Reserve University in a course that enrolled seniors and graduate students majoring in mathematics, statistics, engineering, physics, chemistry, economics and mathematical finance. The last topic proved to be particularly popular among students looking for careers on Wall Street and in research organizations devoted to financial problems. Features Quickly and concisely builds from basic probability theory to advanced topics Suitable as a primary text for an advanced course in diffusion processes and stochastic differential equations Useful as supplementary reading across a range of topics.

关键词： Geometric control methods   Nonlinear differential-algebraic equations   Explicitation   Internal equivalence   Invariant submanifolds   Nonlinear Weierstrass form  

摘要： For nonlinear differential-algebraic equations (DAEs), we define two kinds of equivalences, namely, the external and internal equivalence. Roughly speaking, the word "external" means that we consider a DAE (locally) everywhere and "internal" means that we consider the DAE on its (locally) maximal invariant submanifold (i.e., where its solutions exist) only. First, we revise the geometric reduction method in DAEs solution theory and formulate an implementable algorithm to realize that method. Then a procedure called explicitation with driving variables is proposed to connect nonlinear DAEs with nonlinear control systems and we show that the driving variables of an explicitation system can be reduced under some involutivity conditions. Finally, due to the explicitation, we use some notions from nonlinear control theory to derive two nonlinear generalizations of the Weierstrass form.(c) 2022 The Author(s). Published by Elsevier Inc. This is an open access article under the CC BY license (http://***/licenses/by/4.0/).