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Journal of Wuhan university of Technology(Materials Science) 2024年第5期39卷 1311-1318页

作者： WONG Yeong Yi F L Supian A Radzwan M Musa N F N Abd Karim department of Physics Sultan Idris Education UniversityTanjong Malim 35900Malaysia department of Chemistry Sultan Idris Education UniversityTanjong Malim 35900Malaysia

Calix[n]arenes was utilized to detect PABA,the primary sunscreen *** study investigates the interaction of calix[4]arene(C4),calix[6]arene(C6),and PABA using the Langmuir method and first-principle density functional theory(DFT).Using the Langmuir-Schaefer(LS)technique,an ultrathin film composed of calix[n]arenes and their complexes with PABA was deposited on various *** on the Langmuir study,the PABA molecule was bonded to the lower rims of both C4 and C6 with the host-guest ratio of 1:*** of the LS films formed were then characterized by ultravioletvisible spectroscopy(UV-Vis),Fourier-transform infrared spectroscopy(FTIR)and carbon,hydrogen,nitrogen,sulfur elemental analyzer(CHNS).The band gap reduction obtained in the DFT study denotes the charge transfer interaction with promising reactivity between the calix[n]arenes and *** sensing of PABA by C4 and C6 is successful based on the formation of bonding between them due to the hosts’effective trapping *** outcomes of this study could be applied to drug delivery systems for future pharmaceutical and medical applications.

关键词： calix[n]arenes band gap density functional theory Langmuir-Schaefer PABA sensor

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Cell-free biocatalysis coupled with photo-catalysis and electro-catalysis: Efficient CO2-to-chemical conversion

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Green Energy & Environment 2024年第09期9卷 1366-1383页

作者： Junzhu Yang Chi-Kit Sou Yuan Lu Key Laboratory of Industrial Biocatalysis Ministry of Education Tsinghua University department of Chemical Engineering Tsinghua University

The increasing atmospheric carbon dioxide （CO2） concentration has exposed a series of crises in the earth's ecological *** to effectively fix and convert carbon dioxide into products with added value has attracted the attention of many ***-free enzyme catalytic system coupled with electrical and light have been a promising attempt in the field of biological carbon fixation in recent *** this review,the research progresses of photoenzyme catalysis,electroenzyme catalysis and photo-electroenzyme catalysis for converting carbon dioxide into chemical products in cell-free systems are systematically *** focus on reviewing and comparing various coupling methods and principles of photoenzyme catalysis and electroenzyme catalysis in cell-free systems,especially the materials used in the construction of the coupling system,and analyze and point out the characteristics and possible problems of different coupling ***,we discuss the major challenges and prospects of coupling physical signals and cell-free enzymatic catalytic systems in the field of CO2fixation,suggesting possible strategies to improve the carbon sequestration capacity of such systems.

关键词： CO 2 fixation Cell-free system Enzyme Photoenzyme catalysis Electroenzyme catalysis

Stability analysis of a time-delayed Van der Pol–Helmholtz–Duffing oscillator in fractal space with a non-perturbative approach

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Communications in Theoretical Physics 2024年第4期76卷 22-31页

作者： Yusry O El-Dib department of Mathematics Faculty of EducationAin Shams UniversityRoxyCairoEgypt

The time-delayed fractal Van der Pol–Helmholtz–Duffing(VPHD)oscillator is the subject of this paper,which explores its mechanisms and highlights its stability *** time-delayed technologies are currently garnering significant attention,the focus of this research remains crucially relevant.A non-perturbative approach is employed to refine and set the stage for the system under *** innovative methodologies introduced yield an equivalent linear differential equation,mirroring the inherent nonlinearities of the ***,the incorporation of quadratic nonlinearity into the frequency formula represents a cutting-edge *** analytical solution's validity is corroborated using a numerical *** conditions are ascertained through the residual Galerkin ***,it is observed that the delay parameter,in the context of the fractal system,reverses its stabilizing influence,impacting both the amplitude of delayed velocity and the *** analytical solution's precision is underscored by its close alignment with numerical ***,the study reveals that fractal characteristics emulate damping *** its applicability across diverse nonlinear dynamical systems,this non-perturbative approach emerges as a promising avenue for future research.

关键词： Van der Pol-Helmholtz-Duffing oscillator fractal space time-delay non-perturbative approach stability analysis El-Dib's frequency formula

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Qualitative behavior of discrete-time Caputo-Fabrizio logistic model with Allee effect

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International Journal of Biomathematics 2024年第4期17卷 217-234页

作者： Hatice Karakaya Senol Kartal ilhan Oztirk department of Mathematics Faculty of Science Erciyes UniversityKayseriTurkey department of Science and Mathematics education Faculty of education Nevsehir Haci Bektas Veli University NevsehirTurkey Kapadokya university NevsehirTurkey

The aim of this paper is to investigate the dynamic behaviors of fractional-order logistic model with Allee effects in Caputo-Fabrizio *** of all,we apply the two-step Adams-Bashforth scheme to discretize the fractional-order logistic differential equation and obtain the two-dimensional discrete *** parametric conditions for local asymptotic stability of equilibrium points are obtained by Schur-Chon ***,we discuss the existence and direction for Neimark-Sacker bifurcations with the help of center manifold theorem and bifurcation *** simulations are provided to illustrate theoretical *** is observed that Allee effect plays an important role in stability *** Allee effect in population enhances the stability of the coexisting steady *** additional,the effect of fractional-order derivative on dynamic behavior of the system is also investigated.

关键词： Caputo-Fabrizio fractional derivative two-step Adams-Basforth method logistic differential equation Neimark-Sacker bifurcation Allee effect

When mRNA meets gene editing

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Nano Research 2024年第8期17卷 7337-7356页

作者： Weijie Li Chen Wang Yuan Lu Key Laboratory of Industrial Biocatalysis Ministry of EducationDepartment of Chemical EngineeringTsinghua UniversityBeijing 100084China department of Chemical Engineering Tsinghua UniversityBeijing 100084China

The critical challenge of gene therapy lies in delivering gene editing *** with DNA,while RNA is less stable and more accessible to degrade,it comes with the benefit of lower off-target effects since permanent insertion is not *** review focuses on mRNA-based delivery of gene editing agents,highlighting novel mRNA delivery *** provide context,a comparison is made between three main gene editing agents:programmable nucleases,base editors,and prime *** potential of Cas\pi and transposons is also discussed in this ***,a summary of four main barriers to mRNAbased in vivo delivery is ***,this review detailedly introduced different delivery systems,both viral(lentivirus)and non-viral vectors(genome editing via oviductal nucleic acids delivery,lipid nanoparticles,polymer-based nanoparticles,viruslike-particles,extracellular vesicles,and migrasome).Each delivery strategy is assessed by comparing its advantages and disadvantages to offer a comprehensive and objective overview of the delivery ***,we emphasized the vital role of the protein corona as a critical regulator for ***,we concluded the challenges of mRNA-based gene editing strategies(RNA stability,targeting,potential immunogenicity,cytotoxicity,heterogeneity,and rational design).The purpose of this review is to guide further research and provide a comprehensive analysis of mRNA-based in vivo delivery of gene editing agents in this promising field.

关键词： gene editing mRNA delivery viral vectors non-viral vectors CRISPR

Relationship between physical activity and specific working memory indicators of depressive symptoms in university students

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World Journal of Psychiatry 2024年第1期14卷 148-158页

作者： Qun Zhao Xing Wang Shu-Fan Li Peng Wang Xiang Wang Xin Xin Suo-Wang Yin Zhao-Song Yin Li-Juan Mao School of Physical education Shanghai University of SportShanghai 200438China department of Physical education Donghua UniversityShanghai 201620China

BACKGROUND The detection rate of depression among university students has been increasing in recent years,becoming one of the main psychological diseases that endangers their physical and mental *** to statistics,self-harm and suicide,for which there is no effective intervention,are the second leading causes of *** To explore the relationship between different elements and levels of physical activity and college students’depression-symptom-specific working memory *** Of 143 college students were analyzed using the Beck Depression Self-Rating Scale,the Physical Activity Rating Scale,and the Working Memory *** There was a significant difference between college students with depressive symptoms and healthy college students in completing verbal and spatial working memory(SWM)tasks correctly(all P0.05).CONCLUSION An increase in physical exercise among college students,particularly medium-and high-intensity exercise and exercise of 30 min or more,can improve the correct rate of completing working memory tasks.

关键词： Physical activity Depression symptoms university students Working memory

Synthesis of uniform two-dimensional MoS_(2) films via thermal evaporation

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Nano Research 2024年第4期17卷 3217-3223页

作者： Xue-Wei Lu Zhewei Li Chen-Kai Yang Weijia Mou Liying Jiao Key Laboratory of Organic Optoelectronics and Molecular Engineering of the Ministry of education Department of ChemistryTsinghua UniversityBeijing 100084China

Two-dimensional(2D)molybdenum disulfide(MoS_(2))holds great potential for various applications such as electronic devices,catalysis,lubrication,anti-corrosion and so *** evaporation is a versatile thin film deposition technique,however,the conventional thermal evaporation techniques face challenges in producing uniform thin films of MoS_(2) due to its high melting temperature of 1375℃.As a result,only thick and rough MoS_(2) films can be obtained using these *** address this issue,we have designed a vacuum thermal evaporation system specifically for large-scale preparation of MoS_(2) thin *** using K2MoS4 as the precursor,we achieved reliable deposition of uniform polycrystalline MoS_(2) thin films with a size of 50 mm×50 mm and controllable thickness ranging from 0.8 to 2.4 *** approach also allows for patterned deposition of MoS_(2) using shadow masks and sequential deposition of MoS_(2) and tungsten disulfide(WS_(2)),similar to conventional thermal evaporation ***,we have demonstrated the potential applications of the obtained MoS_(2) thin films in field effect transistors(FETs),memristors and electrocatalysts for hydrogen evolution reaction(HER).

关键词： thermal evaporation molybdenum disulfide two-dimensional memristors hydrogen evolution reaction

Multi-time Collaborative Restoration for Integrated Electrical-gas Distribution Systems Based on Rolling Optimization

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CSEE Journal of Power and Energy Systems 2024年第2期10卷 660-671页

作者： Jingyang Yun Zheng Yan Yun Zhou Peichao Zhang Weidong Hu Key Laboratory of Control of Power Transmission and Conversion of Ministry of education Department of Electrical EngineeringShanghai Jiao Tong University

This paper proposes a multi-time collaborative restoration model for integrated electricity-gas distribution sys-tems(IEGDSs)considering multiple resources after extreme weather *** on the linearized power flow constraints of the unbalanced electrical distribution system(EDS)and gas distribution system(GDS),this problem can be formulated as a mixed-integer linear programming(MILP)*** improve the efficiency and veracity of the solution,a rolling optimiza-tion based two-stage method is developed with the first stage solved by a linear approximation model,and the second stage solved by real-time updated rolling *** solving the MILP problem using rolling optimization,the proposed model and solution method achieve efficient and reliable collaborative restoration of IEGDS considering multiple resources and unbal-anced operation characteristics of *** effectiveness of the proposed model and method is validated by using an IEGDS made of a 37-bus unbalanced EDS and 11-node *** Terms-Electricity-gas system,mix-integer linear programming,power system restoration.

关键词： Electricity-gas system mix-integer linear programming power system restoration

FSCIL-EACA: Few-Shot Class-Incremental Learning Network Based on Embedding Augmentation and Classifier Adaptation for Image Classification

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Chinese Journal of Electronics 2024年第1期33卷 139-152页

作者： Ruru ZHANG Haihong E Meina SONG School of Computer Science Beijing University of Posts and Telecommunications education department Information Network Engineering Research Center Beijing University of Posts and Telecommunications

The ability to learn incrementally is critical to the long-term operation of AI systems. Benefiting from the power of few-shot class-incremental learning(FSCIL), deep learning models can continuously recognize new classes with only a few samples. The difficulty is that limited instances of new classes will lead to overfitting and exacerbate the catastrophic forgetting of the old classes. Most previous works alleviate the above problems by imposing strong constraints on the model structure or parameters, but ignoring embedding network transferability and classifier adaptation(CA), failing to guarantee the efficient utilization of visual features and establishing relationships between old and new classes. In this paper, we propose a simple and novel approach from two perspectives: embedding bias and classifier bias. The method learns an embedding augmented(EA) network with cross-class transfer and class-specific discriminative abilities based on self-supervised learning and modulated attention to alleviate embedding bias. Based on the adaptive incremental classifier learning scheme to realize incremental learning capability,guiding the adaptive update of prototypes and feature embeddings to alleviate classifier bias. We conduct extensive experiments on two popular natural image datasets and two medical datasets. The experiments show that our method is significantly better than the baseline and achieves state-of-the-art results.

关键词： Training Adaptation models Visualization Image recognition Prototypes Self-supervised learning Power capacitors

Investigation on UV-curing Reprocessable Thermosets Bearing Hindered Urea Bonds and Their Composites with Modified Zinc Oxide Nanoparticles

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Chinese Journal of Polymer Science 2024年第6期42卷 751-765页

作者： Jun-Hao Zhou Li-Ming Tang Key Laboratory of Advanced Materials of Ministry of education of China Department of Chemical EngineeringTsinghua UniversityBeijing100084China

In this study,a series of hindered urea bond(HUB)containing polyurethane-urea methacrylate prepolymers and a none HUB containing polyurethane methacrylate prepolymer were prepared using isobornyl methacrylate as the reactive diluent via one-pot *** prepolymers were characterized fully by various ***,their thermosets were fabricated via UV curing in presence of a photo initiator,and their mechanical property and thermal behavior were investigated and *** from the none HUB containing thermoset,the HUB containing thermosets(defined as PUT)could be recycled and reprocessed by hot press under relatively mild conditions with high recovery ratio of mechanical ***,zinc oxide(ZnO)nanoparticles were modified with 3-(trimethoxysilyl)propyl methacrylate and the modified ZnO(defined as ZnO-TPM)was dispersed and polymerized into PUT matrix to prepare their *** influence of ZnO-TPM on the mechanical performance of the composites was evaluated,which indicated that the Young’s modulus and tensile strength increased gradually to the maximum values at ZnO-TPM content of 1 wt%and then *** composites also displayed good reprocessability with improved recovery ratio compared to the pure PUT *** addition,the composite materials exhibited strong UV absorption capacity,implying their potential application in the circumstance where UV-shielding was required.

关键词： Polyurethane-urea methacrylate Hindered urea bond ZnO nanoparticles Reprocessing UV curing

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