Structural Mismatch Research Articles

Facile manufacture technique for lithium-ion batteries composite separator via online construction of fumed SiO2 coating

Booming aspiration of advanced energy storage equipment elevates lithium-ion batteries vastly. Whereas separator with inferior porous structure and compatibility mismatches battery internal medium and raises ion transference rampart. Herein, fumed SiO2 compound separator is designed via ingenious bidirectional drawing technique to optimize the porous structure and realize fumed SiO2 coating online construction during the pore formation process of β-crystal polypropylene (β-iPP) synchronously. Crystal structure measurement, pore construction diagnosis, and physical properties tests disclose that the fumed SiO2 thins coarse fibril structure and homogenizes porous construction of separator. The de-bonding of fumed SiO2/β-iPP interfaces also remains SiO2 on the top-surface and pore internal wall of separator and thus realizes the SiO2 coating online construction, which eliminate the steps required by coating after fabrication of the separator and greatly reduce the production difficulty and cost. Also, the prepared composite separators present reinforced thermal dimensional stability and electrolyte wettability benefited by the SiO2 coating. Electrochemical impedance spectroscopy and cycle tests further uncover that hydrophilic SiO2 nanoparticles lower lithium-ion migration rampart within separator and enhance compatibility with electrodes, which stifles cell resistances and gives LIBs superior high ratio discharge property and cycling durability.

Selenium-Doped Amorphous Black Phosphorus@TiO2/C Heterostructures for High-Performance Li/Na/K Ion Batteries.

Heterostructures have been confirmed to demonstrate better electrochemical performance than their individual building blocks, which is not only attributed to the complementary advantages of diverse materials but also to various synergistic effects, such as increased active sites at the heterointerfaces, enhanced kinetics from a built-in electric field, stable structure due to physical or chemical bonding, etc. However, constructing a desired heterostructure remains greatly challenging owing to the mismatch of crystal structures, atomic spacings, and reaction mechanisms between different electrode materials. In this study, an amorphous heterostructure composed of Se-doped black phosphorus and metal-organic framework (MOF)-derived TiO2/C (Se-BP@TiO2/C) was successfully fabricated using a simple Se-assisted ball-milling method. In addition to the inherent advantages of heterostructures, the novel material also had considerable free volume in the amorphous domains, which not only buffered the volume change of active materials during cycles but also provided space and interconnected channels for ion diffusion. When used as anode materials for Li/Na/K ion batteries, the Se-BP@TiO2/C achieved high specific capacities, good cyclability, and fast rate capability. This work opens up a new route to design amorphous heterostructure electrodes for high-performance battery systems.

Information structure effects on the processing of nouns and verbs: evidence from event-related brain potentials

AbstractElectroencephalographic (EEG) signals can reveal the cost required to deal with information structure mismatches in speech or in text contexts. The present study investigates the costs related to the processing of different associations between the syntactic categories of Noun and Verb and the information categories of Topic and Focus. It is hypothesized that – due to the very nature (respectively, predicative and non-predicative) of verbal and nominal reference – sentences with Topics realized by verbs, and Focuses realized by nouns, should impose greater processing demands, compared to the decoding of nominal Topics and verbal Focuses. Data from event-related potential (ERP) measurements revealed an N400 effect in response to both nouns encoded as Focus and verbs packaged as Topic, confirming that the cost associated with information structure processing follows discourse-driven expectations also with respect to the word-class level.

DOA Estimation for Heterogeneous Wideband Sources Based on Adaptive Space-Frequency Joint Processing

For direction-of-arrival (DOA) estimation of heterogeneous wideband sources, we propose a new adaptive space-frequency joint processing algorithm. The algorithm is implemented in the sparse Bayesian learning (SBL) DOA framework, which is named as ASF-SBL algorithm in this paper. The traditional SBL-based DOA methods suffer from the problem of erroneous DOA estimation due to the structural mismatch between the invariant prior and the sparse coefficients. To solve this problem, the ASF-SBL algorithm employs a new space-frequency correlation prior model that can be adaptively changed to fit heterogeneous DOA scenarios. Specifically, nine alternative space-frequency structural patterns are constructed to represent the joint space-frequency characteristics of spatial sparse signals. By evaluating the space-frequency correlation of the sparse coefficients updated in each iteration under SBL framework, a suitable pattern is selected from the nine choices to determine the adaptive prior of each coefficient. This adaptive method leads to accurate DOA estimation in different wideband sources scenarios. In addition, we introduce a distributed processing method to extend the ASF-SBL algorithm to two-dimensional DOA estimation. This extension is achieved by decoupling the DOA estimation into two one-dimensional estimations. The decoupling avoids the problems of a huge redundant dictionary and excessive computational complexity caused by the combination of azimuth and elevation angles. Numerical simulations show that the ASF-SBL algorithm is superior to existing algorithms in DOA estimation of heterogeneous sources.

Mixed metal node effect in zeolitic imidazolate frameworks.

We synthesized two series of bimetallic (zinc and cobalt) zeolitic imidazolate frameworks (ZIF-62) under different solvothermal conditions. It is found that the structure of the derived ZIF crystals is highly sensitive to synthesis conditions. One series possesses the standard ZIF-62 structure, whereas the other has a mixed structure composed of both the standard structure and an unknown one. The standard series exhibits a slight negative deviation from linearity of melting temperature (Tm) and glass transition temperature (Tg) with the substitution of Co for Zn. In contrast, the new series displays a stronger negative deviation. These negative deviations from linearity indicate the mixed metal node effect in bimetallic ZIF-62 due to the structural mismatch between Co2+ and Zn2+ and to the difference in their electronic configurations. The new series involves both cobalt-rich and zinc-rich phases, whereas the standard one shows one homogeneous phase. Density functional theory calculations predict that the substitution of Co for Zn increases the bulk modulus of the ZIF crystals. This work indicates that the structure, melting behaviour, and mechanical properties of ZIFs can be tuned by metal node substitution and by varying the synthetic conditions. Both series of ZIFs have higher glass forming abilities due to their higher Tg/Tm ratios (0.77–0.84) compared to most good glass formers.

Improving Charge Injection at Gold/Conjugated Polymer Contacts by Polymer Insulator-Assisted Annealing for Transistors.

The poor chemical miscibility between metal and organic materials usually leads to both structural and energetic mismatches at gold/organic interfaces, and thereby, high contact resistance of organic electronic devices. This study shows that the contact resistance of organic field-effect transistors is significantly reduced by one order of magnitude, by reforming the contact interface between gold electrodes and conjugated polymers upon a polymer insulator-assisted thermal annealing. Upon an optimized solution process, the conjugated polymer is homogenously distributed within the amorphous polymer insulator matrix with relatively low glass transition temperature, and thus, even a moderate annealing temperature can induce sufficient motion of conjugated polymer chains to simultaneously adjust the polymer orientation and improve the packing of gold atoms. Consequently, gold/conjugated polymer contact is reorganized after annealing, which improves both charge transport from bulk gold to interface and charge injection from gold into conjugated polymers. This method, with appropriate insulator matrix, is effective for improving the injection of both holes and electrons, and widely applicable for many unipolar and ambipolar conjugated polymers to optimize the device performance and simultaneously increase the optical transparency (over 80%). A frequency doubler and a phase modulator are demonstrated, respectively, using the ambipolar transistors with optimized charge injection properties.

ЗНАЧЕНИЕ МОРФОЛОГИЧЕСКИХ РАЗЛИЧИЙ ПРИ ОБУЧЕНИИ МОНГОЛОВ РУССКОЙ ГРАММАТИКЕ

Statement of the problem. Russian and Mongolian languages ​​are unrelated, multi-structured, differing from each other in all linguistic aspects, first of all, in grammar. However, unfortunately, their systemic comparative description is still lacking. Besides, the Russian language which used to be compulsory for study as a foreign language in all educational institutions nowadays is studied only in the 7th-9th grades of comprehensive schools. All this negatively affects the Russian language teachers training, many of whom have linguistic and speech competencies insufficiently formed; therefore, in our opinion, the approach to teaching Russian grammar in the Mongolian audience should be improved. The purpose of the article is as follows: on the basis of the comparative characteristics of verbs, nouns and prepositions, to predict the most acute zones of interference in the construction of syntactic structures and to help avoid negative mutual influence. As a result, the main areas of interference are determined. This is, firstly, the structural mismatch of Russian one-piece sentences with their Mongolian equivalents and, secondly, syntactic models with determinants in general and with subject-object ones, in particular. Knowing this will allow the teacher, when planning, to devote more time to these structures, consistent continuous work with them, which ultimately will help the formation of linguistic and speech competence.

Stretchable, Washable, and Rewritable Electrophoretic Displays with Tough Hydrogel–Elastomer Interface

AbstractTremendous advances in stretchable and biocompatible electronics have led to broad requirements of wearable display devices. However, most devices suffer from insufficient reliability owing to structural mismatch and bubbles under repeated deformation. To address this issue, this article presents a stretchable electrophoretic display (SEPD) with reinforced adhesion by in situ adhesion decoration between the hydrogel electrode and the elastomer display layer. The SEPD with a maximum strain of over 80% can still operate properly. Moreover, the SEPD device is endowed with stretchable, washable, rewritable, and erasable properties owing to the inherent characteristics of the elastomer‐based materials used. Arbitrary texts and patterns can be drawn and maintained for over 43 days of bistability without a predetermined patterned electrode or a thin‐film transistor as the addressing switches. In addition, the casting and blade coatings used in this work are suitable for mass production. The proposed hybrid structure with tough adhesion provides a new paradigm for other wearable devices.

The Development of Digital Finance and Firms’ Transformation from Virtual to Real

Firms’ transformation from virtual to real means that firms allocate more capital from non-productive areas to productive areas, which is shown as the decrease of the level of firm financialization. The inefficient supply of traditional financial services is one of the factors that promotes firm financialization. In recent years, with the development and popularization of new technology, digital finance emerges at the historic moment. In essence, digital finance utilizes network technologies such as artificial intelligence, big data, cloud computing, Internet of Things, and blockchain to not only expand the accessibility of financial services, but also solve the problems of high risk premium and high operating cost generated in traditional financial services. Therefore, in view of the development scale of China’s internet economy and its leading position in the world’s technical practice, and considering the huge effect of digital finance on traditional financial services, it is necessary to explore the effect mechanism of digital finance on firm financialization from the perspective of Fintech progress.Based on the annual data of A-share listed firms in Shanghai and Shenzhen stock exchanges from 2011 to 2018, this paper examines the effect of digital finance development on firm financialization. The empirical study finds that the development of digital finance can reduce the level of firm financialization. The mechanism test finds that digital finance inhibits firm financialization mainly by weakening the precautionary motivation of firms. Further study finds that the inhibition of digital finance development on firm financialization only exists in the weak samples of the structural mismatch of traditional finance. In other words, the inhibitory effect of digital finance on firm financialization is more significant in private firms, manufacturing firms and growth-stage firms. Meanwhile, compared with short-term financial assets, long-term financial assets of firms are more significantly inhibited by the development of digital finance. With the standardization of the regulatory environment and the strengthening of supervision, the development of digital finance has a more significant inhibiting effect on firm financialization.The research contributions of this paper are mainly reflected in the following three aspects: Firstly, from the perspective of digital finance, it reveals the effect mechanism of Fintech progress on firm financialization, and clarifies the important role of Fintech progress in the interaction between real economy and virtual economy. Secondly, from the perspective of firm financialization, it empirically investigates the microeconomic consequences of digital finance, and supplements related literatures on the economic consequences of digital finance. Thirdly, the findings of this paper are conducive to understanding the positive role of digital finance in correcting financial mismatch. In terms of policy suggestions, on the one hand, for firms, digital finance can effectively alleviate the financial pressure and financing constraints. Especially for manufacturing firms, start-ups and private firms, digital finance can play a role of inclusive finance. On the other hand, for regulators, it is necessary to effectively regulate digital firms and the digital economy to avoid risks such as industry monopoly, data security and regulatory loopholes.

Insights into the atomic structure of the interface of ferroelectric Hf0.5Zr0.5O2 grown epitaxially on La2/3Sr1/3MnO3

Epitaxial growth of ${\mathrm{Hf}}_{0.5}{\mathrm{Zr}}_{0.5}{\mathrm{O}}_{2}$ (HZO) thin films allows for the stabilization of the metastable orthorhombic phase with robust ferroelectric properties. So far, the ferroelectric phase is most commonly stabilized on perovskite substrates upon insertion of a buffer layer of ${\mathrm{La}}_{2/3}{\mathrm{Sr}}_{1/3}\mathrm{Mn}{\mathrm{O}}_{3}$ (LSMO); however, little is known about the role played by the LSMO buffer layer and the interface between HZO and LSMO. Inspection of a $\mathrm{HZO}/\mathrm{LSMO}/\mathrm{SrTi}{\mathrm{O}}_{3}$ heterostructure by scanning transmission electron microscope imaging and electron energy loss spectroscopy shows that, despite the substantial structural mismatch between HZO and LSMO, the interface between them is relatively sharp spanning \ensuremath{\sim}2 atomic layers. The LSMO surface, expected to be mostly $\mathrm{Mn}{\mathrm{O}}_{2}$ terminated, undergoes a chemical reconstruction consisting of the substitution of the Mn cations by a mixture of Hf/Zr cations. Density functional theory calculations show that the substitution of Mn by Hf on the $\mathrm{Mn}{\mathrm{O}}_{2}$-terminated surface of LSMO is energetically favorable, as the higher electronegativity and valence of Hf with respect to Mn balances the surface charge of the $\mathrm{Mn}{\mathrm{O}}_{2}$ layer.

Crystal Chemistry of Six Grossular Garnet Samples from Different Well-Known Localities

Two isotropic grossular (ideally Ca3Al2Si3O12) samples from (1) Canada and (2) Tanzania, three optically anisotropic grossular samples (3, 4, 5) from Mexico, and one (6) anisotropic sample from Italy were studied. The crystal structure of the six samples was refined in the cubic space group Ia3¯d, using monochromatic synchrotron high-resolution powder X-ray diffraction (HRPXRD) data and the Rietveld method. The compositions of the samples were obtained from electron microprobe analyses (EPMA). The HRPXRD traces show a single cubic phase for two isotropic samples, whereas the four anisotropic samples contain two different cubic phases that were also resolved using X-ray elemental line scans, backscattered electron (BSE) images, and elemental maps. Structural mismatch from two cubic phases intergrown in the birefringent samples gives rise to strain-induced optical anisotropy. Considering the garnet general formula, [8]X3[6]Y2[4]Z3[4]O12, the results of this study show that with increasing unit-cell parameter, the Y-O distance increases linearly and rather steeply, the average <X-O> distance increases just slightly in response to substitution mainly on the Y site, while the Z-O distance remains nearly constant. The X and Z sites in grossular contain Ca and Si atoms, respectively; both sites show insignificant substitutions by other atoms, which is supported by a constant Z-O distance and only a slight increase in the average <X-O> distance. The main cation exchange is realized in the Y site, where Fe3+ (ionic radius = 0.645 Å) replaces Al3+ (ionic radius = 0.545 Å), so the Y-O distance increases the most.

Spontaneous chiral self-assembly of CdSe@CdS nanorods

Spontaneous chiral self-assembly of CdSe@CdS nanorods

Tricomponent Supramolecular Multiblock Copolymers with Tunable Composition via Sequential Seeded Growth

AbstractSynthesis of supramolecular block co‐polymers (BCP) with small monomers and predictive sequence requires elegant molecular design and synthetic strategies. Herein we report the unparalleled synthesis of tri‐component supramolecular BCPs with tunable microstructure by a kinetically controlled sequential seeded supramolecular polymerization of fluorescent π‐conjugated monomers. Core‐substituted naphthalene diimide (cNDI) derivatives with different core substitutions and appended with β‐sheet forming peptide side chains provide perfect monomer design with spectral complementarity, pathway complexity and minimal structural mismatch to synthesize and characterize the multi‐component BCPs. The distinct fluorescent nature of various cNDI monomers aids the spectroscopic probing of the seeded growth process and the microscopic visualization of resultant supramolecular BCPs using Structured Illumination Microscopy (SIM). Kinetically controlled sequential seeded supramolecular polymerization presented here is reminiscent of the multi‐step synthesis of covalent BCPs via living chain polymerization. These findings provide a promising platform for constructing unique functional organic heterostructures for various optoelectronic and catalytic applications.

Tricomponent Supramolecular Multiblock Copolymers with Tunable Composition via Sequential Seeded Growth.

Synthesis of supramolecular block co-polymers (BCP) with small monomers and predictive sequence requires elegant molecular design and synthetic strategies. Herein we report the unparalleled synthesis of tri-component supramolecular BCPs with tunable microstructure by a kinetically controlled sequential seeded supramolecular polymerization of fluorescent π-conjugated monomers. Core-substituted naphthalene diimide (cNDI) derivatives with different core substitutions and appended with β-sheet forming peptide side chains provide perfect monomer design with spectral complementarity, pathway complexity and minimal structural mismatch to synthesize and characterize the multi-component BCPs. The distinct fluorescent nature of various cNDI monomers aids the spectroscopic probing of the seeded growth process and the microscopic visualization of resultant supramolecular BCPs using Structured Illumination Microscopy (SIM). Kinetically controlled sequential seeded supramolecular polymerization presented here is reminiscent of the multi-step synthesis of covalent BCPs via living chain polymerization. These findings provide a promising platform for constructing unique functional organic heterostructures for various optoelectronic and catalytic applications.

High-rate and ultralong-life Mg–Li hybrid batteries based on highly pseudocapacitive dual-phase TiO2 nanosheet cathodes

Although Mg–Li hybrid batteries are proposed as an alternative to Mg-batteries, the lack of dual-ion compatible cathodes are limiting their practical application. Herein, we report a high-rate and ultralong-life Mg–Li hybrid battery based on a dual-phase TiO2 cathode. Highly pseudocapacitive hierarchical two-dimensional TiO2 consists of anatase (60%) and bronze (40%) nanocrystallites forming interfaces due to crystal structure mismatch. This dual-phase hierarchical cathode exhibits excellent pseudocapacitance (up to 92%), specific capacities (235 mAh/g @ 25 mA/g), rate performance (120 mAh/g @ 1A/g) cycling stability (~87% after 3000 cycles @ 1A/g) and coulombic efficiency (~100%). These results are vastly superior to the previously reported values for TiO2 based Mg–Li hybrid battery cathodes. Only minimal structural changes are observed during the charge-discharge of two-dimensional TiO2 electrode. Outstanding electrochemical performance of dual-phase TiO2 nanosheet cathode is attributed to the superior pseudocapacitive Mg/Li-ion diffusion through nanointerfaces between anatase and bronze crystallites. While other structural features such as 2D-morphology, ultrathin nature, mesoporosity, and high surface area act as secondary factors. The demonstrated approach for efficient pseudocapacitive Mg/Li-ion intercalation enhanced by nanointerfaces can be further exploited in the development of other high performance electrodes for advanced Mg–Li hybrid batteries.

Phonological development in school-aged Kuwaiti Arabic children with Down syndrome: A pilot study

BackgroundStudies on atypical phonological development are very limited for Arabic, and to date no studies on Arabic have investigated the development of phonology in children with conditions such as Down Syndrome. Arabic, like other Semitic languages, is rich in consonants and consonantal variation. However, it differs greatly from region to region, and so reports on individual dialects or regional dialects are necessary. Kuwaiti Arabic, the focus of the present paper, is similar to other dialects in the Gulf region. AimThis is a preliminary study to examine the phonological development of school-aged Kuwaiti Arabic–speaking children with Down Syndrome in order to start to address the research gap noted above. Methods & ProceduresSix Kuwaiti Arabic-speaking children were recruited for this pilot study from integrated public schools where children with disabilities and typically developing children are enrolled in the State of Kuwait: three male and three female students, age range of 5;10–12;3 years. All participants had the same single word speech test of 100 words. The first author, a native speaker of Kuwaiti Arabic, audio-recorded and phonetically transcribed the sample with the help of two speech-language pathologists from Kuwait. Reliability was confirmed by the first author and another expert rater. Both match and mismatch analyses were performed and compared to existing literature. Outcomes & ResultsOverall consonant accuracy across participants was 50%, with a variety of matches across consonant categories. However, the participants also exhibited a wide range of mismatches across positions in words and phonological features (place, manner, and laryngeal features). Place substitutions were the most frequent. Some sounds exhibited double (place and manner) mismatches. The most common word structure mismatch was consonant cluster reduction (no matches for word-initial clusters). Mismatch patterns resembled both those of normally developing Kuwaiti children and those of English speakers with Down Syndrome in certain ways. Conclusions & ImplicationsThis pilot study provides preliminary information for clinicians regarding the speech or children with Down Syndrome (DS), not only in Kuwait but also in the Gulf region where there are similarities to Kuwaiti Arabic.

TransTailor: Pruning the Pre-trained Model for Improved Transfer Learning

The increasing of pre-trained models has significantly facilitated the performance on limited data tasks with transfer learning. However, progress on transfer learning mainly focuses on optimizing the weights of pre-trained models, which ignores the structure mismatch between the model and the target task. This paper aims to improve the transfer performance from another angle - in addition to tuning the weights, we tune the structure of pre-trained models, in order to better match the target task. To this end, we propose TransTailor, targeting at pruning the pre-trained model for improved transfer learning. Different from traditional pruning pipelines, we prune and fine-tune the pre-trained model according to the target-aware weight importance, generating an optimal sub-model tailored for a specific target task. In this way, we transfer a more suitable sub-structure that can be applied during fine-tuning to benefit the final performance. Extensive experiments on multiple pre-trained models and datasets demonstrate that TransTailor outperforms the traditional pruning methods and achieves competitive or even better performance than other state-of-the-art transfer learning methods while using a smaller model. Notably, on the Stanford Dogs dataset, TransTailor can achieve 2.7% accuracy improvement over other transfer methods with 20% fewer FLOPs.

Accelerated lattice constant prediction of perovskite materials (ABX3, A2BB′O6) using partial least squares and principal component regression methods

Since device performance is greatly influenced by minute variations in the crystal structure of its constituent materials, reliably predicting the lattice parameters of perovskites can aid in minimizing structural mismatch and improve film integrity. Herein, we present the application of partial least squares regression (PLSR) and principal component regression (PCR) methods to predict the lattice constant of ABX3 and A2BB′O6 perovskites, with Shannon ionic radii (r), atomic number (Z), electronegativity (χ) and density (ρ) as model inputs. Our results revealed that, depending on the number of components used, PLSR and PCR estimates had better mean absolute percentage error than estimates from existing studies. Moreover, computed loadings can be used to describe the effect of each model input to the regression estimate. Overall, this study paves the way for rapid and simple elemental property-based perovskite material design and discovery.

Stretchable and suturable fibre sensors for wireless monitoring of connective tissue strain

Implantable sensors can be used to monitor biomechanical strain continuously. However, three key challenges need to be addressed before they can be of use in clinical practice: the structural mismatch between the sensors and tissue or organs should be eliminated; a practical suturing attachment process should be developed; and the sensors should be equipped with wireless readout. Here, we report a wireless and suturable fibre strain-sensing system created by combining a capacitive fibre strain sensor with an inductive coil for wireless readout. The sensor is composed of two stretchable conductive fibres organized in a double helical structure with an empty core, and has a sensitivity of around 12. Mathematical analysis and simulation of the sensor can effectively predict its capacitive response and can be used to modulate performance according to the intended application. To illustrate the capabilities of the system, we use it to perform strain measurements on the Achilles tendon and knee ligament in an ex vivo and in vivo porcine leg. A capacitive, fibre-like stretchable strain sensor, formed of two conductors in a double helical structure, can be combined with an inductive coil to create a wireless strain-sensing system for biomedical applications.

Dynamic optimization integrating modifier adaptation using transient measurements

In this work, a dynamic optimizer (DO) is enhanced with elements taken from the Modifier Adaptation (MA) methodology for Real-Time Optimization (RTO). The objective is to use the capability of MA methodologies to reach the real optimum of a process despite the existence of process-model mismatch. The modifiers are computed during a process transient, without waiting for several steady states to occur, speeding up the time required to reach the plant optimum. The architecture proposed includes a modified dynamic optimization, a module for estimating the model states and an additional module for direct estimation of the modifiers during transient. The proposed approach was applied in a well-known benchmark example: the Williams-Otto reactor, where the model and process have significant parametric and structural mismatch. The results show that the proposed integration is capable of bringing the process closer to the real optimal economic operation point.