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Mean-square exponential stability of stochastic Volterra systems in infinite dimensions

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Science China(Information Sciences) 2024年第10期67卷 298-314页

作者： lin FU Shiguo PENG Feiqi deng Quanxin ZHU School of Automation Guangdong University of Technology School of Automation Science and Engineering South China University of Technology Key Laboratory of Computing and Stochastic Mathematics(Ministry of Education) School of Mathematics and StatisticsHunan Normal University

Over the past decade, the study of stability theory in integro-differential systems has grown significantly owing to their relevance in solving physical and engineering problems, such as viscoelasticity and thermo-viscoelasticity in materials with memory properties. This paper concentrates on a class of infinite-dimensional stochastic integro-differential systems. We establish the well-posedness of the system and identify mild solutions to the system and an abstract stochastic Cauchy problem. This identification is identified by employing a semigroup approach combined with Yosida approximation. We derive sufficient conditions that ensure the mean-square exponential stability of mild solutions to the system boils down to the boundedness of a certain function and a norm estimate for the stochastic part. These conditions are implemented through the semigroup approach and the composition operator method. Illustrative examples are provided and the obtained theoretical results are validated by numerical simulations.

关键词： stochastic integro-differential equations mean-square exponential stability stochastic distributed parameter systems Hardy space composition operators

Rational design and energy catalytic application of high-loading single-atom catalysts

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Rare Metals 2024年第10期43卷 4844-4866页

作者： Zi-Wei deng Yue Liu Jie lin Wen-Xing Chen Energy and Catalysis Center School of Materials Science and EngineeringBeijing Institute of Technology Ningbo Institute of Materials Technology and Engineering Chinese Academy of Science

It is well known that single-atom catalysts(SACs)have become a hot topic in the field of catalysis due to their advantages such as 100% metal atom utilization efficiency,high catalytic activity and selectivity compared with conventional catalysts and nanocatalysts. However, the isolated metal atoms on SACs have thermodynamic instability and tend to agglomerate, which limit their catalytic ***, it is of great significance to synthesize stable and high-loading single-atom catalysts(HLSACs). In this paper,we review the research progress of HLSACs from two aspects:design and application. Firstly, we comprehensively introduce the synthesis strategies of HLSACs, namely, top-down and bottom-up methods. Secondly, we overview the application status of HLSACs in three fields: electrocatalysis, thermal catalysis and photocatalysis. Finally, we summarize the development prospects and challenges of HLSACs.

关键词： Design Electrocatalysis High-loading single-atom catalysts Photocatalysis Thermal catalysis

Direct somatic embryogenesis and related gene expression networks in leaf explants of Hippeastrum ‘Bangkok Rose’

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Horticultural Plant Journal 2024年第2期10卷 556-572页

作者： Jingjue Zeng Yi deng Shahid Iqbal Jiarui Zhang Kunlin Wu Guohua Ma lin Li Guangyi Dai Rufang deng lin Fang Songjun Zeng Guangdong Provincial Key Laboratory of Applied Botany South China Botanical GardenChinese Academy of SciencesGuangzhouGuangdong 510650China University of the Chinese Academy of Sciences Beijing 100049China South China National Botanical Garden GuangzhouGuangdong 510650China Zhaoqing Branch Center of Guangdong Laboratory for lingnan Modern Agricultural Science and Technology ZhaoqingGuangdong 526000China Horticultural Science Department North Florida Research and Education CenterUniversity of Florida/IFASQuincyFL 32351USA Public Laboratory of South China Botanical Garden Chinese Academy of SciencesGuangzhouGuangdong 510650China Key Laboratory of South China Agricultural Plant Molecular Analysis and Gene Improvement South China Botanical GardenChinese Academy of SciencesGuangzhouGuangdong 510650China

Hippeastrum, a highly diverse genus in the Amaryllidaceae family, is a valuable ornamental bulbous flowering plant. Somatic embryogenesis(SE) is an efficient method for mass production of Hippeastrum plantlets. Previous studies have been devoted to the in vitro propagation of Hippeastrum, but the SE and its regulatory networks are rarely reported. In this study, we established a direct SE method of Hippeastrum Bangkok Rose' using leaf bases as explants. MS supplemented with 1.00 mg·L^(-1)NAA +1.00 mg·L^(-1)KT + 0.25 mg·L^(-1)TDZ was the optimal medium for SE. Histological observations showed that the bipolar somatic embryo originated from the epidermal cell layer and underwent initiation,globular, scutellar and coleoptile stages. During SE, endogenous hormones of IAA, CTK, ABA, and SA were highly accumulated. Transcriptomic analysis revealed the genes encoding auxin biosynthesis/metabolic enzymes and efflux carriers were induced, while the auxin receptor of TIR1 and ARF transcriptional repressor of Aux/IAA were down-regulated and up-regulated, respectively, leading to suppression of auxin signaling. In contrast, cytokine signaling was promoted at the early stage of SE, as biosynthesis, transport, and signaling components were *** stress-related genes were up-regulated at the early or late stages of SE. Chromatin remodeling could also be dynamically regulated via distinct expression enzymes that control histone methylation and acetylation during SE. Moreover, key SE regulators, including WOXs and SERKs were highly expressed along with SE. Overall, the present study provides insights into the SE regulatory mechanisms of the Hippeastrum.

关键词： Hippeastrum Tissue culture Somatic embryogenesis Gene regulation

Method of fabricating artificial rock specimens based on extrusion free forming(EFF)3D printing

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Journal of Rock Mechanics and Geotechnical Engineering 2024年第4期16卷 1455-1466页

作者： Xiaomeng Shi Tingbang deng Sen lin Chunjiang Zou Baoguo Liu Key Laboratory for Urban Underground Engineering of the Ministry of Education Beijing Jiaotong UniversityBeijing100044China School of Civil Engineering Beijing Jiaotong UniversityBeijing100044China Department of Civil Engineering Monash UniversityMelbourne3800Australia

Three-dimensional(3D)printing technology has been widely used to create artificial rock samples in rock *** 3D printing can create complex fractures,the material still lacks sufficient similarity to natural *** free forming(EFF)is a 3D printing technique that uses clay as the printing material and cures the specimens through high-temperature *** this study,we attempted to use the EFF technology to fabricate artificial rock *** results show the physico-mechanical properties of the specimens are significantly affected by the sintering temperature,while the nozzle diameter and layer thickness also have a certain *** specimens are primarily composed of SiO_(2),with mineral compositions similar to that of natural *** density,uniaxial compressive strength(UCS),elastic modulus,and tensile strength of the printed specimens fall in the range of 1.65–2.54 g/cm3,16.46–50.49 MPa,2.17–13.35 GPa,and 0.82–17.18 MPa,*** is capable of simulating different types of rocks,especially mudstone,sandstone,limestone,and ***,the simulation of hard rocks with UCS exceeding 50 MPa still requires validation.

关键词： Artificial rock 3D printing Extrusion free forming(EFF) Similarity analysis Mechanical properties

Improvement of epilepsy secondary to acquired immunodeficiency syndrome with intestinal microbiota preparations:a case report

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Acta Epileptologica 2024年第2期7卷 137-142页

作者： Chuhui lin Ting Zeng Yuhong deng Department of Clinical Nutrition the Second Affiliated Hospital of Guangzhou Medical UniversityGuangzhou 510260China Institute of Neuroscience and Department of Neurology the Second Affiliated Hospital of Guangzhou Medical UniversityGuangzhou 510260China

Background Epilepsy secondary to acquired immunodeficiency syndrome(AIDS)can be challenging to *** potential interactions between antiretroviral drugs and antiepileptic drugs may result in the failure of both ***,it is crucial to develop more effective strategies to enhance the clinical outcomes of *** presentation We report a case of epilepsy secondary to *** administration of Bacteroides Fragilis 839(BF839),the secondary generalized tonic-clonic seizures disappeared,the frequency of complex partial seizures decreased by 70%,and the duration of each episode was ***,long-term diarrhea associated with antiretroviral therapy for AIDS resolved,and the syphilis serofast reaction turned *** serious adverse reactions were observed during the three-year follow *** This case report suggests that the specific gut microbiota preparation could possibly improve refrac-tory epilepsy in HIV patients while also potentially alleviating adverse reactions to antiretroviral drugs and concurrent syphilis *** case may provide a new perspective for the treatment of HIV infection/AIDS.

关键词： Acquired immunodefciency syndrome Epilepsy Bacteroides fragilis

Theoretical understanding of correlation between magnetic phase transition and the superconducting dome in high-Tc cuprates

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Science China(Physics,Mechanics & Astronomy) 2024年第2期67卷 167-173页

作者： Chen Zhang Cai-Xin Zhang Su-Huai Wei Haiqing lin Hui-Xiong deng State Key Laboratory of Superlattices and Microstructures Institute of SemiconductorsChinese Academy of SciencesBeijing 100083China Center of Materials Science and Optoelectronics Engineering University of Chinese Academy of SciencesBeijing 100049China Beijing Computational Science Research Center Beijing 100193China

Many issues concerning the origin of high-temperature superconductivity(HTS)are still under *** example,how the magnetic order varies with doping and its relationship with the superconducting temperature(Tc);and why Tcalways peaks near the quantum critical *** this paper,taking hole-doped La_(2)CuO_(4)as a classical example,we employ the first-principles band structure and total energy calculations with Monte Carlo simulations to explore how the symmetry-breaking magnetic ground state evolves with hole doping and the origin of a dome-shaped superconductivity region in the phase *** demonstrate that the local antiferromagnetic order and doping play key roles in determining the electron-phonon coupling,thus ***,the La_(2)CuO_(4)possesses a checkerboard local antiferromagnetic ground *** the hole doping increases,Tcincreases with the enhanced electron-phonon coupling *** as the doping increases further,the strength of the antiferromagnetic interaction weakens and spin fluctuation *** the critical doping level,a magnetic phase transition occurs that reduces the local antiferromagnetism-assisted electron-phonon coupling,thus diminishing the *** superconductivity disappears in the heavily overdoped region when the ferromagnetic order *** observations could account for why cuprates have a dome-shaped superconductivity region in the phase *** study,thus,contributes to a fundamental understanding of the correlation between doping,local magnetic order,and superconductivity of HTS.

关键词： high-temperature superconductivity antiferromagnetic order electron-phonon coupling doping effect cuprates

Preface to integrative stratigraphy,biotas,and paleogeographical evolution of the Qinghai-Tibetan Plateau and its surrounding areas

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Science China Earth Sciences 2024年第4期67卷 895-898页

作者： Shuzhong SHEN lin DING Maoyan ZHU Xiangdong WANG Tao deng State Key Laboratory for Mineral Deposits Research School of Earth Sciences and Engineering and Frontiers Science Center for Critical Earth Material CyclingNanjing UniversityNanjing 210023China State Key Laboratory of Tibetan Plateau Earth System Resources and EnvironmentInstitute of Tibetan Plateau ResearchChinese Academy of SciencesBeijing 100101China State Key Laboratory of Palaeobiology and Stratigraphy Nanjing Institute of Geology and Palaeontology and Center for Excellence in Life and PalaeoenvironmentChinese Academy of SciencesNanjing 210008China College of Earth and Planetary Sciences University of Chinese Academy of SciencesBeijing 100049China Key Laboratory of Vertebrate Evolution and Human Origins of Chinese Academy of Sciences Institute of Vertebrate Paleontology and PaleoanthropologyChinese Academy of SciencesBeijing 100044China

The Qinghai-Tibetan Plateau(QTP)is well known as the Roof of the World,the Third Pole and the Asian Water *** spans a vast area from the Pamir Plateau in the west to the Longmenshan-Hengduan Mountains in the east,from the Himalaya Mountains in the south to the Kunlun-Qilian Mountains in the *** stretches approximately 1,200 km from north to south and 2,500 km from east to *** did the QTP start to uplift?This is still controversial between early and late Cenozoic *** some scholars advocated its uplift since the India-Asia continental collision at about 65 million years ago in the Paleogene(e.g.,Ding et al.,2017,2022),and the others suggested its uplift since the Miocene(Zheng and Wu,2018).

关键词： uplift Tibetan north

Aerodynamic/stealth design of S-duct inlet based on discrete adjoint method

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Applied Mathematics and Mechanics(English Edition) 2024年第4期45卷 725-746页

作者： Jun deng Ke ZHAO lin ZHOU Wei ZHANG Bowen SHU Jiangtao HUANG Zhenghong GAO School of Aeronautics Northwestern Polytechnical UniversityXi’an 710072China Aerospace Technology Institute of China Aerodynamic Research and Development CenterMianyang 621000Sichuan ProvinceChina

It is a major challenge for the airframe-inlet design of modern combat aircrafts,as the flow and electromagnetic wave propagation in the inlet of stealth aircraft are very *** this study,an aerodynamic/stealth optimization design method for an S-duct inlet is *** upwind scheme is introduced to the aerodynamic adjoint equation to resolve the shock wave and flow *** multilevel fast multipole algorithm(MLFMA)is utilized for the stealth adjoint equation.A dorsal S-duct inlet of flying wing layout is optimized to improve the aerodynamic and stealth *** the aerodynamic and stealth characteristics of the inlet are effectively ***,the optimization results are analyzed,and it shows that the main contradiction between aerodynamic characteristics and stealth characteristics is the centerline and crosssectional *** S-duct is smoothed,and the cross-sectional area is increased to improve the aerodynamic characteristics,while it is completely opposite for the stealth *** radar cross section(RCS)is reduced by phase cancelation for low frequency *** method is suitable for the aerodynamic/stealth design of the aircraft airframe-inlet system.

关键词： S-duct inlet aerodynamic/stealth optimization design discrete adjoint upwind scheme multilevel fast multipole algorithm(MLFMA)

Bimetallic CoNi single atoms supported on three-dimensionally ordered mesoporous chromia:highly active catalysts for n-hexane combustion

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Green Energy & Environment 2024年第7期9卷 1122-1137页

作者： Xiuqing Hao Yuxi Liu Jiguang deng lin Jing Jia Wang Wenbo Pei Hongxing Dai Beijing Key Laboratory for Green Catalysis and Separation Key Laboratory of Beijing on Regional Air Pollution ControlKey Laboratory of Advanced Functional MaterialsEducation Ministry of ChinaLaboratory of Catalysis Chemistry and NanoscienceDepartment of Chemical EngineeringFaculty of Environment and LifeBeijing University of TechnologyBeijing100124China

Developing the alternative supported noble metal catalysts with low cost,high catalytic efficiency,and good resistance toward carbon dioxide and water vapor is critically demanded for the oxidative removal of volatile organic compounds(VOCs).In this work,we prepared the mesoporous chromia-supported bimetallic Co and Ni single-atom(Co_(1)Ni_(1)/meso-Cr_(2)O_(3))and bimetallic Co and Ni nanoparticle(Co_(NP)Ni_(NP)/mesoCr_(2)O_(3))catalysts adopting the one-pot polyvinyl pyrrolidone(PVP)-and polyvinyl alcohol(PVA)-protecting approaches,*** results indicate that the Co_(1)Ni_(1)/meso-Cr_(2)O_(3)catalyst exhibited the best catalytic activity for n-hexane(C_(6)H_(14))combustion(T_(50%)and T_(90%)were 239 and 263℃ at a space velocity of 40,000 mL g^(-1)h^(-1);apparent activation energy and specific reaction rate at 260℃ were 54.7 kJ mol^(-1)and 4.3×10^(-7)mol g^(-1)_(cat)s^(-1),respectively),which was associated with its higher(Cr^(5+)+Cr^(6+))amount,large n-hexane adsorption capacity,and good lattice oxygen mobility that could enhance the deep oxidation of n-hexane,in which Ni_(1) was beneficial for the enhancements in surface lattice oxygen mobility and low-temperature reducibility,while Co_(1) preferred to generate higher contents of the high-valence states of chromium and surface oxygen species as well as adsorption and activation of n-hexane.n-Hexane combustion takes place via the Mars van Krevelen(MvK)mechanism,and its reaction pathways are as follows:n-hexane→olefins or 3-hexyl hydroperoxide→3-hexanone,2-hexanone or 2,5-dimethyltetrahydrofuran→2-methyloxirane or 2-ethyl-oxetane→acrylic acid→CO_x→CO_(2)and H_(2)O.

关键词： Three-dimensional ordered mesoporous chromium oxide Supported bimetallic single-atom catalyst Cobalt-nickel single atoms n-Hexane combustion Catalytic reaction mechanism