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Science China Chemistry 2024年第9期67卷 2941-2948页

作者： Yang-Ping Zhang Shao-Min Pei Wen-Fa Chen Bin-Wen Liu Xiao-Ming Jiang guo-Cong guo State Key Laboratory of Structural Chemistry Fujian Institute of Research on the Structure of MatterChinese Academy of SciencesFuzhou 350002China Fujian Science&Technology Innovation Laboratory for Optoelectronic Information of China Fuzhou 350108China School of Physical Science and Technology Shanghai Tech UniversityShanghai 201210China

Non-centrosymmetric(NCS)structure is an indispensable prerequisite for second-order nonlinear optical(NLO)***,the mainstream approach for designing new NCS structures still relies on chemical substitution,necessitating an urgent infusion of fresh *** this work,two isomorphic sulfides AeMn_(6)Ga_(6)S_(16)(Ae=Ca,1;Sr,2)are afforded by modifying the skeleton of centrosymmetric(CS)Mn_(2)Ga_(2)S_(5) via introducing strong electropositive alkaline-earth ***,the incorporation of Ca^(2+)/Sr^(2+)cations allows the elementary[MnGaS_(9)]_(∞)chains to reconfigure into bumpy[MnS_(6)]-[GaS_(4)]layers in a new engagement manner,thus enabling the conversion from CS to NCS *** modifications cause not only strong second-harmonic generation(SHG)responses(~1.5×benchmark AgGaS_(2)@1,700 nm),but also significantly feasible bandgaps(2.60-2.64 e V)compared to the sulfide Mn_(2)Ga_(2)S_(5)(1.36 e V),which ultimately facilitate ultrahigh laser-induced damage thresholds(4.4-6.6×AgGaS_(2)@1,064 nm for compounds 1 and 2).The present study offers an ingenious approach for the transformation of CS to NCS structure.

关键词： second-harmonic generation non-centrosymmetrical structure NLO functional motif solid-state method

Machine learning model based on non-convex penalized huberized-SVM

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Journal of Electronic Science and Technology 2024年第1期22卷 81-94页

作者： Peng Wang Ji guo Lin-Feng Li School of Finance and Economics Xizang Minzu UniversityXianyang712082China Research Center for Quality Development of Xizang Special Industries Xianyang712082China School of Computer Science and Technology Xinjiang UniversityUrumqi830017China

The support vector machine(SVM)is a classical machine learning *** the hinge loss and least absolute shrinkage and selection operator(LASSO)penalty are usually used in traditional ***,the hinge loss is not differentiable,and the LASSO penalty does not have the Oracle *** this paper,the huberized loss is combined with non-convex penalties to obtain a model that has the advantages of both the computational simplicity and the Oracle property,contributing to higher accuracy than traditional *** is experimentally demonstrated that the two non-convex huberized-SVM methods,smoothly clipped absolute deviation huberized-SVM(SCAD-HSVM)and minimax concave penalty huberized-SVM(MCP-HSVM),outperform the traditional SVM method in terms of the prediction accuracy and classifier *** are also superior in terms of variable selection,especially when there is a high linear correlation between the *** they are applied to the prediction of listed companies,the variables that can affect and predict financial distress are accurately filtered *** all the indicators,the indicators per share have the greatest influence while those of solvency have the weakest *** companies can assess the financial situation with the indicators screened by our algorithm and make an early warning of their possible financial distress in advance with higher precision.

关键词： Huberized loss Machine learning Non-convex penalties Support vector machine(SVM)

Tailoring of a robust asymmetric aramid nanofibers/MXene aerogel film for enhanced infrared thermal camouflage and Joule heating performances

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Nano Research 2024年第3期17卷 1990-1998页

作者： Wanbin Dang Wei guo Wenting Chen Qiuyu Zhang Key Laboratory of Special Functional and Smart Polymer Materials of Ministry of Industry and Information Technology School of Chemistry and Chemical EngineeringNorthwestern Polytechnical UniversityXi’an 710072China

The development of infrared(IR)surveillance technology has led to a growing interest in thermal ***,the trade-off relationship between low IR-emissivity and thermal insulation hinders the advance of thermal camouflage ***,guided by multi-physics simulation,we show a design of asymmetric aramid nanofibers/MXene(ANF/MXene)aerogel film that realizes high-efficient thermal camouflage *** rationale is that the asymmetric structure contains a thermal-insulation three-dimensional(3D)network part to prevent effective heat transfer and a low IR-emissivity(~0.3)dense surface layer to suppress radiative heat *** is remarkable that the synergy mechanism in the topology structure contributes to over 40%reduction of target radiation ***,the tailored asymmetric ANF/MXene aerogel film also enables sound mechanical properties such as a Young’s modulus of 44.4 MPa and a tensile strength of 1.3 MPa,superior to most aerogel *** also exhibits great Joule heating performances including low driving voltage(4 V),fast thermal response(<10 s),and long-term stability,further enabling its versatile thermal camouflage *** work offers an innovative design concept to configure multifunctional structures for next-generation thermal management applications.

关键词： asymmetric aerogel film low infrared(IR)-emissivity thermal insulation IR thermal camouflage Joule heating performance

Experimental and numerical demonstration of hierarchical time-delay reservoir computing based on cascaded VCSELs with feedback and multiple injections

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Science China(Information Sciences) 2024年第2期67卷 279-290页

作者： Xingxing guo Shuiying XIANG Xingyu CAO Biling GU State Key Laboratory of Integrated Service Networks Xidian University State Key Discipline Laboratory of Wide Bandgap Semiconductor Technology School of MicroelectronicsXidian University

In this paper, we propose and demonstrate experimentally and numerically a hierarchical timedelay optical reservoir computing(RC) system based on cascaded vertical-cavity surface-emitting lasers(VCSELs) with feedback and multiple injections. The prediction performance characteristics of the hierarchical time-delay RC system based on cascaded VCSELs under different reservoir layers are ***, the prediction performance of the hierarchical time-delay RC system is first improved and saturates as the number of reservoir layers increases. Besides, the impacts of key factors on predicting the hierarchical time-delay RC system are also analyzed in detail experimentally and numerically. This proposed hierarchical time-delay RC system based on VCSELs is useful for the further development of RC systems and may be beneficial to improve the ability of RC systems to solve more complex problems.

关键词： vertical-cavity surface-emitting laser reservoir computing neuromorphic photonics time-delay system information processing

Memristive oscillator to memristive map,energy characteristic

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Science China(Technological Sciences) 2024年第5期67卷 1567-1578页

作者： guo YiTong MA Jun ZHANG XiaoFeng HU XiKui College of Electrical and Information Engineering Lanzhou University of TechnologyLanzhou730050China Department of Physics Lanzhou University of TechnologyLanzhou730050China School of Science Chongqing University of Posts and TelecommunicationsChongqing400065China

Most of nonlinear oscillators composed of capacitive and inductive variables can obtain the Hamilton energy by using the Helmholtz theorem when the models are rewritten in equivalent vector *** energy functions for biophysical neurons can be obtained by applying scale transformation on the physical field energy in their equivalent neural *** dynamical systems often have exact energy functions,while some mathematical models just suggest generic Lyapunov functions,and the energy function is effective to predict mode *** this paper,a memristive oscillator is approached by two kinds of memristor-based nonlinear circuits,and the energy functions are defined to predict the dependence of oscillatory modes on energy *** absence of capacitive variable for capacitor,the physical time t and charge q are converted into dimensionless variables by using combination of resistance and inductance(L,R),e.g.,τ=t×R/*** energy function for each memristive map is proposed by applying the similar weights as energy function for the memristive *** example,energy function for the map is obtained by replacing the variables and parameters of the memristive oscillator with corresponding variables and parameters for the memristive *** memristive map prefers to keep lower average energy than the memristive oscillator,and chaos is generated in a discrete system with two *** scheme is helpful for energy definition in maps,and it provides possible guidance for verifying the reliability of maps by considering the energy characteristic.

关键词： Hamilton energy memristor Helmholtz theorem scale transformation memristive circuit

Applications of genetic code expansion technology in eukaryotes

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Protein & Cell 2024年第5期15卷 331-363页

作者： Qiao-ru guo Yu J.Cao State Key Laboratory of Chemical Oncogenomic Guangdong Provincial Key Laboratory of Chemical GenomicsPeking University Shenzhen Graduate SchoolShenzhen 518055China Institute of Chemical Biology Shenzhen Bay LaboratoryShenzhen 518132China

Unnatural amino acids(UAAs)have gained significant attention in protein engineering and drug development owing to their ability to introduce new chemical functionalities to *** eukaryotes,genetic code expansion(GCE)enables the incorporation of UAAs and facilitates posttranscriptional modification(PTM),which is not feasible in prokaryotic *** is also a powerful tool for cell or animal imaging,the monitoring of protein interactions in target cells,drug development,and switch ***,there is keen interest in utilizing GCE in eukaryotic *** review provides an overview of the application of GCE in eukaryotic systems and discusses current challenges that need to be addressed.

关键词： genetic code expansion unnatural amino acid eukaryotes basic research therapeutic applications

Dual-salt poly(tetrahydrofuran) electrolyte enables quasi-solid-state lithium metal batteries to operate at -30 ℃

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Journal of Energy Chemistry 2024年第9期96卷 456-463页

作者： Zhiyong Li Zhuo Li Rui Yu Xin guo School of Materials Science and Engineering State Key Laboratory of Material Processing and Die&Mould TechnologyHuazhong University of Science and TechnologyWuhan 430074HubeiChina The State Key Laboratory of Refractories and Metallurgy and Institute of Advanced Materials and Nanotechnology Wuhan University of Science and TechnologyWuhan 430081HubeiChina

The stable operation of solid-state lithium metal batteries at low temperatures is plagued by severe restrictions from inferior electrolyte-electrode interface compatibility and increased energy barrier for Li^(+)***,we prepare a dual-salt poly(tetrahydrofuran)-based electrolyte consisting of lithium hexafluorophosphate and lithium difluoro(oxalato)borate(LiDFOB).The Li-salt anions(DFOB−)not only accelerate the ring-opening polymerization of tetrahydrofuran,but also promote the formation of highly ion-conductive and sustainable interphases on Li metal anodes without sacrificing the Li^(+)conductivity of electrolytes,which is favorable for Li^(+)transport kinetics at low *** of this polymer electrolyte in Li||LiFePO_(4)cells show 82.3%capacity retention over 1000 cycles at 30℃and endow stable discharge capacity at−30℃.Remarkably,the Li||LiFePO4 cells retain 52%of their room-temperature capacity at−20℃and 0.1 *** rational design of dual-salt polymer-based electrolytes may provide a new perspective for the stable operation of quasi-solid-state batteries at low temperatures.

关键词： Poly(tetrahydrofuran) Dual-salt electrolyte Solidel ectrolyte interphase Low-temperature operation Quasi-solid-state battery

Physical neural networks with self-learning capabilities

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Science China(Physics,Mechanics & Astronomy) 2024年第8期67卷 23-42页

作者： Weichao Yu Hangwen guo Jiang Xiao Jian Shen State Key Laboratory of Surface Physics and Institute for Nanoelectronic Devices and Quantum Computing Fudan UniversityShanghai 200433China Zhangjiang Fudan International Innovation Center Fudan UniversityShanghai 201210China Department of Physics Fudan UniversityShanghai 200433China Shanghai Research Center for Quantum Sciences Shanghai 201315China Collaborative Innovation Center of Advanced Microstructures Nanjing 210093China

Physical neural networks are artificial neural networks that mimic synapses and neurons using physical systems or *** networks harness the distinctive characteristics of physical systems to carry out computations effectively,potentially surpassing the constraints of conventional digital neural networks.A recent advancement known as“physical self-learning”aims to achieve learning through intrinsic physical processes rather than relying on external *** article offers a comprehensive review of the progress made in implementing physical self-learning across various physical *** learning strategies that contribute to the realization of physical self-learning are *** challenges in understanding the fundamental mechanism of learning,this work highlights the progress towards constructing intelligent hardware from the ground up,incorporating embedded self-organizing and self-adaptive dynamics in physical systems.

关键词： self-learning physical neural networks neuromorphic computing physical learning

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On the convergence of tracking differentiator with multiple stochastic disturbances

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Science China(Information Sciences) 2024年第2期67卷 157-169页

作者： Zehao WU Huacheng ZHOU Baozhu guo Feiqi DENG School of Mathematics and Big Data Foshan University School of Mathematics and Statistics Central South University Academy of Mathematics and Systems Science Chinese Academy of Sciences Systems Engineering Institute South China University of Technology

This paper investigates the convergence, noise-tolerance, and filtering performance of a tracking differentiator in the presence of multiple stochastic disturbances for the first time. We consider a general case wherein the input signal is corrupted by additive colored noise, and the tracking differentiator is disturbed by additive colored noise and white noise. The tracking differentiator is shown to track the input signal and its generalized derivatives in the mean square sense. Further, the almost sure convergence can be achieved when the stochastic noise affecting the input signal is vanishing. Herein, numerical simulations are performed to validate the theoretical results.

关键词： tracking differentiator convergence noise-tolerance filtering performance multiple stochastic disturbances

Design of an automated robotic microinjection system for batch injection of zebrafish embryos and larvae

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Microsystems & Nanoengineering 2024年第1期10卷 89-103页

作者： Zhongyi guo Nana Ai Wei Ge Qingsong Xu Department of Electromechanical Engineering Faculty of Science and TechnologyUniversity of MacaoMacaoChina Department of Biomedical Sciences and Centre of Reproduction Development and Aging(CRDA)Faculty of Health SciencesUniversity of MacaoMacaoChina

This paper presents the design of a vision-based automated robotic microinjection system for batch injection of both zebrafish embryos and larvae.A novel visual recognition algorithm based on an automatic threshold and excessive dilatation is introduced to accurately identify the center of zebrafish embryos and larval yolks.A corresponding software system is developed using the producer-consumer model as the framework structure,and a friendly user interface is designed to allow operators to choose from a range of desired functions according to their different *** addition,a novel microstructural agarose device is designed and fabricated to simultaneously immobilize mixed batches of embryos and ***,a prototype microinjection system is fabricated by integrating hardware devices with visual *** experimental study is conducted to verify the performance of the robotic microinjection *** results show that the reported system can accurately identify zebrafish embryos and larvae and efficiently complete batch microinjection tasks of the mixtures with an injection success rate of 92.05%in 13.88 s per *** with manual and existing microinjection systems,the proposed system demonstrates the merits of versatility,excellent efficiency,high success rate,high survival rate,and sufficient stability.

关键词： zebra automated hardware