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1.
Small ; : e2403831, 2024 Jul 01.
Article in English | MEDLINE | ID: mdl-38949398

ABSTRACT

Lithium metal batteries are regarded as promising candidates for next-generation energy storage systems. However, their anodes are susceptible to interfacial instability due to significant volume changes, which significantly impacts the cycle life of lithium metal batteries. Here, a rapid method for the fabrication of 3D-hosts with interface modified layers is reported. A simple infiltration and heating process enables the transformation of copper foam into Zn-BDC-modified copper foam within 1 min, rendering it suitable for use as a current collector for lithium metal anodes. The Zn-BDC nanosheets with high lithiophilicity are uniformly distributed on the surface of the current collector, facilitating the uniform deposition of lithium and reducing the volume change. Consequently, the half cell exhibits a remarkably low overpotential (26 mV) at a current-density of 4 mA cm-2 and is cycled stably for 1000 h. Furthermore, it demonstrates a significant enhancement in performance in the LiFePO4 full cell. This study provides a crucial reference on the connection between the interfacial modification of the current collector and the lithium deposition behavior, which promotes the practicalization of lithium metal anodes.

2.
Small ; 20(24): e2308522, 2024 Jun.
Article in English | MEDLINE | ID: mdl-38161261

ABSTRACT

The Ni and Fe dual-atom catalysts still undergo strikingly attenuation under high current density and high overpotential. To ameliorate the issue, the ionic liquids with different cations or anions are used in this work to regulate the micro-surface of nitrogen-doped carbon supported Ni and Fe dual-atom sites catalyst (NiFe-N-C) by an impregnation method. The experimental data reveals the dual function of ionic liquids, which enhances CO2 adsorption ability and modulates electronic structure, facilitating CO2 anion radical (CO2 •¯) stabilization and decreasing onset potential. The theoretical calculation results prove that the attachment of ionic liquids modulates electronic structure, reduces energy barrier of CO2 •¯ formation, and enhances overall ECR performance. Based on these merits, BMImPF6 modified NiFe-N-C (NiFe-N-C/BMImPF6) achieves the high CO faradaic efficiency of 91.9% with a CO partial current density of -120 mA cm-2 at -1.0 V. When the NiFe-N-C/BMImPF6 is assembled as cathode of Zn-CO2 battery, it delivers the highest power density of 2.61 mW cm-2 at 2.57 mA cm-2 and superior cycling stability. This work will afford a direction to modify the microenvironment of other dual-atom catalysts for high-performance CO2 electroreduction.

3.
JACS Au ; 3(5): 1284-1300, 2023 May 22.
Article in English | MEDLINE | ID: mdl-37234122

ABSTRACT

With the ever-growing demand for sustainability, designing polymeric materials using readily accessible feedstocks provides potential solutions to address the challenges in energy and environmental conservation. Complementing the prevailing strategy of varying chemical composition, engineering microstructures of polymer chains by precisely controlling their chain length distribution, main chain regio-/stereoregularity, monomer or segment sequence, and architecture creates a powerful toolbox to rapidly access diversified material properties. In this Perspective, we lay out recent advances in utilizing appropriately designed polymers in a wide range of applications such as plastic recycling, water purification, and solar energy storage and conversion. With decoupled structural parameters, these studies have established various microstructure-function relationships. Given the progress outlined here, we envision that the microstructure-engineering strategy will accelerate the design and optimization of polymeric materials to meet sustainability criteria.

4.
Front Hum Neurosci ; 16: 844529, 2022.
Article in English | MEDLINE | ID: mdl-35634209

ABSTRACT

A broad sketch for a model of speech production is outlined which describes developmental aspects of its cognitive-linguistic and sensorimotor components. A description of the emergence of phonological knowledge is a central point in our model sketch. It will be shown that the phonological form level emerges during speech acquisition and becomes an important representation at the interface between cognitive-linguistic and sensorimotor processes. Motor planning as well as motor programming are defined as separate processes in our model sketch and it will be shown that both processes revert to the phonological information. Two computational simulation experiments based on quantitative implementations (simulation models) are undertaken to show proof of principle of key ideas of the model sketch: (i) the emergence of phonological information over developmental stages, (ii) the adaptation process for generating new motor programs, and (iii) the importance of various forms of phonological representation in that process. Based on the ideas developed within our sketch of a production model and its quantitative spell-out within the simulation models, motor planning can be defined here as the process of identifying a succession of executable chunks from a currently activated phoneme sequence and of coding them as raw gesture scores. Motor programming can be defined as the process of building up the complete set of motor commands by specifying all gestures in detail (fully specified gesture score including temporal relations). This full specification of gesture scores is achieved in our model by adapting motor information from phonologically similar syllables (adapting approach) or by assembling motor programs from sub-syllabic units (assembling approach).

5.
BMC Genomics ; 22(1): 529, 2021 Jul 10.
Article in English | MEDLINE | ID: mdl-34246232

ABSTRACT

BACKGROUND: In soybean, some circadian clock genes have been identified as loci for maturity traits. However, the effects of these genes on soybean circadian rhythmicity and their impacts on maturity are unclear. RESULTS: We used two geographically, phenotypically and genetically distinct cultivars, conventional juvenile Zhonghuang 24 (with functional J/GmELF3a, a homolog of the circadian clock indispensable component EARLY FLOWERING 3) and long juvenile Huaxia 3 (with dysfunctional j/Gmelf3a) to dissect the soybean circadian clock with time-series transcriptomal RNA-Seq analysis of unifoliate leaves on a day scale. The results showed that several known circadian clock components, including RVE1, GI, LUX and TOC1, phase differently in soybean than in Arabidopsis, demonstrating that the soybean circadian clock is obviously different from the canonical model in Arabidopsis. In contrast to the observation that ELF3 dysfunction results in clock arrhythmia in Arabidopsis, the circadian clock is conserved in soybean regardless of the functional status of J/GmELF3a. Soybean exhibits a circadian rhythmicity in both gene expression and alternative splicing. Genes can be grouped into six clusters, C1-C6, with different expression profiles. Many more genes are grouped into the night clusters (C4-C6) than in the day cluster (C2), showing that night is essential for gene expression and regulation. Moreover, soybean chromosomes are activated with a circadian rhythmicity, indicating that high-order chromosome structure might impact circadian rhythmicity. Interestingly, night time points were clustered in one group, while day time points were separated into two groups, morning and afternoon, demonstrating that morning and afternoon are representative of different environments for soybean growth and development. However, no genes were consistently differentially expressed over different time-points, indicating that it is necessary to perform a circadian rhythmicity analysis to more thoroughly dissect the function of a gene. Moreover, the analysis of the circadian rhythmicity of the GmFT family showed that GmELF3a might phase- and amplitude-modulate the GmFT family to regulate the juvenility and maturity traits of soybean. CONCLUSIONS: These results and the resultant RNA-seq data should be helpful in understanding the soybean circadian clock and elucidating the connection between the circadian clock and soybean maturity.


Subject(s)
Arabidopsis Proteins , Arabidopsis , Circadian Clocks , Arabidopsis Proteins/genetics , Circadian Clocks/genetics , Circadian Rhythm/genetics , Dissection , Gene Expression Regulation, Plant , Glycine max/genetics
6.
Front Psychol ; 10: 1462, 2019.
Article in English | MEDLINE | ID: mdl-31354560

ABSTRACT

A comprehensive model of speech processing and speech learning has been established. The model comprises a mental lexicon, an action repository and an articulatory-acoustic module for executing motor plans and generating auditory and somatosensory feedback information (Kröger and Cao, 2015). In this study a "model language" based on three auditory and motor realizations of 70 monosyllabic words has been trained in order to simulate early phases of speech acquisition (babbling and imitation). We were able to show that (i) the emergence of phonetic-phonological features results from an increasing degree of ordering of syllable representations within the action repository and that (ii) this ordering or arrangement of syllables is mainly shaped by auditory information. Somatosensory information helps to increase the speed of learning. Especially consonantal features like place of articulation are learned earlier if auditory information is accompanied by somatosensory information. It can be concluded that somatosensory information as it is generated already during the babbling and the imitation phase of speech acquisition is very helpful especially for learning features like place of articulation. After learning is completed acoustic information together with semantic information is sufficient for determining the phonetic-phonological information from the speech signal. Moreover it is possible to learn phonetic-phonological features like place of articulation from auditory and semantic information only but not as fast as when somatosensory information is also available during the early stages of learning.

7.
J Am Chem Soc ; 141(2): 794-799, 2019 01 16.
Article in English | MEDLINE | ID: mdl-30588805

ABSTRACT

Controlled/living radical polymerization was developed to synthesize branched polyacrylates and polystyrene with tunable degrees of branching and low dispersities. This method is based on a polymerization-induced branching process that occurs when n-butyl α-bromoacrylate is copolymerized under atom transfer radical polymerization conditions. This novel branching polymerization demonstrates excellent synthetic versatility, enabling the preparation of complex macromolecular architectures constructed from branched-polymer building blocks.


Subject(s)
Acrylic Resins/chemical synthesis , Polystyrenes/chemical synthesis , Acrylates/chemistry , Molecular Structure , Polymerization
8.
J Asian Nat Prod Res ; 17(12): 1231-8, 2015.
Article in English | MEDLINE | ID: mdl-26699877

ABSTRACT

Three new aaptamine derivatives (1-3), together with six known related compounds (4-9), have been isolated from the South China Sea sponge Aaptos aaptos. The structures of all compounds were unambiguously elucidated on the basis of spectroscopic analyses. Compounds 1, 4, 5, 7, and 9 showed cytotoxic activities against HeLa, K562, MCF-7, and U937 cell lines with IC50 values in the range of 0.90-12.32 µM.


Subject(s)
Antineoplastic Agents/isolation & purification , Naphthyridines/isolation & purification , Porifera/chemistry , Animals , Antineoplastic Agents/chemistry , Antineoplastic Agents/pharmacology , China , Drug Screening Assays, Antitumor , HeLa Cells , Humans , K562 Cells , Marine Biology , Molecular Structure , Naphthyridines/chemistry , Naphthyridines/pharmacology , U937 Cells
9.
Chem Pharm Bull (Tokyo) ; 63(6): 438-42, 2015.
Article in English | MEDLINE | ID: mdl-26027468

ABSTRACT

Chemical investigation on CH2Cl2 extract of the marine sponge Diacarnus megaspinorhabdosa resulted in the isolation of two new farnesylacetone derivatives 1-2, a new γ-lactone 3, a known dinorditerpenone 4 and four known norsesterterpene peroxides 5-8. Their structures were elucidated by using one and two dimensional (1D and 2D)-NMR, high resolution-electrospray ionization (HR-ESI)-MS, and comparison with the literature. Compounds 1 and 2 were cis/trans-olefinic isomers and determined through nuclear Overhauser effect spectroscopy (NOESY) experiment. The absolute configuration of 3 was established by comparison of circular dichroism (CD) data with known lactones. The cytotoxic activities of the compounds were evaluated against five cancer cell lines, and compound 3 showed moderate cytotoxicity activities against cancer cell lines HeLa, H446, NCI-H460, SGC-7901 and MCF-7, with IC50 values in the range of 18.5 to 47.1 µM.


Subject(s)
Antineoplastic Agents/pharmacology , Biological Products/pharmacology , Lactones/pharmacology , Peroxides/pharmacology , Porifera/chemistry , Sesterterpenes/pharmacology , Terpenes/pharmacology , Animals , Antineoplastic Agents/chemistry , Antineoplastic Agents/isolation & purification , Biological Products/chemistry , Biological Products/isolation & purification , Cell Line, Tumor , HeLa Cells , Humans , Lactones/chemistry , Lactones/isolation & purification , Neoplasms/drug therapy , Peroxides/chemistry , Peroxides/isolation & purification , Sesterterpenes/chemistry , Sesterterpenes/isolation & purification , Terpenes/chemistry , Terpenes/isolation & purification
10.
Front Psychol ; 5: 236, 2014.
Article in English | MEDLINE | ID: mdl-24688478

ABSTRACT

Based on the incremental nature of knowledge acquisition, in this study we propose a growing self-organizing neural network approach for modeling the acquisition of auditory and semantic categories. We introduce an Interconnected Growing Self-Organizing Maps (I-GSOM) algorithm, which takes associations between auditory information and semantic information into consideration, in this paper. Direct phonetic-semantic association is simulated in order to model the language acquisition in early phases, such as the babbling and imitation stages, in which no phonological representations exist. Based on the I-GSOM algorithm, we conducted experiments using paired acoustic and semantic training data. We use a cyclical reinforcing and reviewing training procedure to model the teaching and learning process between children and their communication partners. A reinforcing-by-link training procedure and a link-forgetting procedure are introduced to model the acquisition of associative relations between auditory and semantic information. Experimental results indicate that (1) I-GSOM has good ability to learn auditory and semantic categories presented within the training data; (2) clear auditory and semantic boundaries can be found in the network representation; (3) cyclical reinforcing and reviewing training leads to a detailed categorization as well as to a detailed clustering, while keeping the clusters that have already been learned and the network structure that has already been developed stable; and (4) reinforcing-by-link training leads to well-perceived auditory-semantic associations. Our I-GSOM model suggests that it is important to associate auditory information with semantic information during language acquisition. Despite its high level of abstraction, our I-GSOM approach can be interpreted as a biologically-inspired neurocomputational model.

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