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Journal of Magnesium and Alloys 2024年第4期12卷 1619-1637页

作者： Yongbiao Yang Jinxuan guo Cuiying Wang Wenxuan Jiang Zhimin zhang Qiang Wang Xing zhang College of Materials Science and Engineering North University of ChinaLane 3Xueyuan RoadTaiyuanShanxi 030051China North Hongyang mechanical and electronic limited company of Henan Province China

Hot torsion tests for AZ80 magnesium alloy were carried out in the temperature range of 380℃-260℃,with a constant decreasing temperature rate of 10℃/s in order to weaken the basal texture and refine the *** results indicated that the average grain sizes were refined forming gradient structure with increasing specimen radial position from center(12.2-5.4μm),and that the initial basal texture intensity of the extruded magnesium alloy was weakened from 46.2 to ***,the extension twins(ETs)could be disintegrated from the twins forming separated twins with smaller ***,ETs with the same twin variant intersecting with each other could be coalesced forming grains with similar orientation,while ETs with different twin variants were separated by twins boundaries contributing to grain ***,in addition to the conventional continuous dynamic recrystallized(CDRX)grains with 30˚orientation rotated around C-axis of the parent grains,CDRXed grains with 30˚rotation around a-axis and random rotation axis were also ***,the CDRX evolution induced twins were also elaborated,exhibiting the complex competition between CDRX and *** torsion deformation with constant decreasing temperatures rate is an effective way of grain refinement and texture modification.

关键词： Texture Microstructure Hot torsion Decreasing temperature AZ80

A model reduction approach for discrete-time linear time-variant systems with delayed inputs

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Science China(Information Sciences) 2024年第4期67卷 197-217页

作者： Ai-guo WU Guang-Ren DUAN Yu WANG Jie zhang School of Mechanical Engineering and Automation Harbin Institute of Technology(Shenzhen) HIT Wuhu Robot Technology Research Institute Center for Control Science and Technology Southern University of Science and Technology

A model reduction approach is presented for discrete-time linear time-variant input-delayed systems. According to this proposed approach, a dynamical variable is constructed by taking advantage of the current state and historical information of input. It is revealed that the behavior of this dynamical variable is governed by a discrete-time linear delay-free system. It is worth noting that the presented variable transformation does not require the system matrix to be invertible. Based on the reduced delay-free models,stabilizing control laws can be easily obtained for the original delayed system. For the case with a single input delay, the constructed variable is an exact prediction for the future state, and thus the stabilizing control law could be designed by replacing the future state with its prediction. Finally, three discrete-time periodic systems with delayed input are employed to illustrate how to utilize the presented model reduction approaches.

关键词： reduction approach predictor-based feedback time-varying systems delayed input periodic system

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先进压缩空气储能系统的基础研究与应用进展

Engineering 2024年第3期34卷 246-269页

作者： Xinjing zhang Ziyu Gao Bingqian Zhou Huan guo Yujie Xu Yulong ding Haisheng Chen Institute of Engineering Thermophysics Chinese Academy of SciencesBeijing 100190China University of Chinese Academy of Sciences Beijing 100049China Birmingham Centre for Energy Storage&School of Chemical Engineering University of BirminghamBirmingham B152TTUK

Decarbonization of the electric power sector is essential for sustainable ***-carbon generation technologies,such as solar and wind energy,can replace the CO_(2)-emitting energy sources(coal and natural gas plants).As a sustainable engineering practice,long-duration energy storage technologies must be employed to manage imbalances in the variable renewable energy supply and electricity *** air energy storage(CAES)is an effective solution for balancing this mismatch and therefore is suitable for use in future electrical systems to achieve a high penetration of renewable energy *** study introduces recent progress in CAES,mainly advanced CAES,which is a clean energy technology that eliminates the use of fossil fuels,compared with two commercial CAES plants at Huntorf and McIntosh which are conventional ones utilizing fossil *** CAES include adiabatic CAES,isothermal CAES,liquid air energy storage,supercritical CAES,underwater CAES,and CAES coupled with other *** principles and configurations of these advanced CAES technologies are briefly discussed and a comprehensive review of the state-of-the-art technologies is presented,including theoretical studies,experiments,demonstrations,and *** comparison and discussion of these CAES technologies are summarized with a focus on technical maturity,power sizing,storage capacity,operation pressure,round-trip efficiency,efficiency of the components,operation duration,and investment *** application trends were *** paper presents a comprehensive reference for developing novel CAES systems and makes recommendations for future research and development to facilitate their application in several areas,ranging from fundamentals to applications.

关键词： Compressed air energy storage Fundamentals Applications Technological parameters Comparison

Oral peptide therapeutics for diabetes treatment: State-of-the-art and future perspectives

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Acta Pharmaceutica Sinica B 2024年第5期14卷 2006-2025页

作者： Bingwen ding Zhu Zhu Cong guo Jiaxin Li Yong Gan Miaorong Yu State Key Laboratory of Drug Research and Center of Pharmaceutics Shanghai Institute of Materia MedicaChinese Academy of SciencesShanghai 201203China University of Chinese Academy of Sciences Beijing 100049China School of Pharmacy Henan UniversityKaifeng 475004China NMPA Key Laboratory for Quality Research and Evaluation of Pharmaceutical Excipients National Institutes for Food and Drug ControlBeijing 100050China

Diabetes,characterized by hyperglycemia,is a major cause of death and disability ***,such as insulin and glucagon-like peptide-1(GLP-1)analogs,have shown promise as treatments for diabetes due to their ability to mimic or enhance insulin's actions in the *** to subcutaneous injection,oral administration of anti-diabetic peptides is a preferred ***,biological barriers significantly reduce the efficacy of oral peptide *** advancements in drug delivery systems and formulation techniques have greatly improved the oral delivery of peptide therapeutics and their efficacy in treating *** review will highlight(1)the benefits of oral anti-diabetic peptide therapeutics;(2)the biological barriers for oral peptide delivery,including pH and enzyme degradation,intestinal mucosa barrier,and biodistribution barrier;(3)the delivery platforms to overcome these biological ***,the review will discuss the prospects in this *** information provided in this review will serve as a valuable guide for future developments in oral anti-diabetic peptide therapeutics.

关键词： Oral peptides Diabetes Delivery platforms Insulin Glucagon-like peptide-1 Biodistribution Biological barriers Targeted delivery

Ultralow-phase-noise and broadband frequency-hopping coupled optoelectronic oscillator under quiet point operation

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Photonics Research 2024年第08期12卷 1785-1793页

作者： HUI LIU MINGYANG guo TIAN zhang JIAN DAI KUN XU State Key Laboratory of Information Photonics and Optical Communications Beijing University of Posts and Telecommunications School of Electronic Engineering Beijing University of Posts and Telecommunications

Advancements in microwave photonics have yielded novel approaches for generating high-purity microwave sources. Among these, optoelectronic oscillators（OEOs） and coupled optoelectronic oscillators（COEOs） have demonstrated the capability to generate frequency-independent microwaves with exceptionally low phase ***, the tunability of the oscillators is rather limited due to the necessity for narrowband electronic bandpass filters, presenting challenges in achieving both wide and rapid tuning capabilities. Here, we present a COEO featuring ultralow phase noise, flexible tuning capability, and high robustness. This is achieved through a quiet point（QP）-operated harmonic mode-locked fiber laser, which effectively mitigates optical amplifier noise and supermode competition, thus significantly diminishing the necessity for ultra-narrow electronic filters. Due to the liberated tuning ability, we present an oscillator that can be tuned from 2 GHz to 18 GHz, with phase noise as low as-140 d Bc/Hz at 10 k Hz under the QP operation. We then illustrate the practical application of the proposed oscillator in generating frequency-hopping signals with consistent spurious modes less than-85 d Bc,absolute phase noise below-135 d Bc/Hz at 10 k Hz, hopping resolution of 1.25 MHz, and fractional frequency stability below 6.1 × 10-12at 1 s averaging time when locked to a reference. The presented COEO structure emerges as a compelling solution for agile and low-noise microwave sources in advanced wireless communication and radar systems.

关键词： Bandpass filters Beam splitters Microwave photonics Mode-locked fiber lasers Optical amplifiers Phase noise

Inverse reliability analysis and design for tunnel face stability considering soil spatial variability

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Journal of Rock Mechanics and Geotechnical Engineering 2024年第5期16卷 1552-1564页

作者： Zheming zhang Jian Ji Xiangfeng guo Siang Huat Goh Key Laboratory of Ministry of Education for Geomechanics and Embankment Engineering Hohai UniversityNanjing210098China Department of Civil and Environmental Engineering National University of SingaporeSingapore

The traditional deterministic analysis for tunnel face stability neglects the uncertainties of geotechnical parameters,while the simplified reliability analysis which models the potential uncertainties by means of random variables usually fails to account for soil spatial *** overcome these limitations,this study proposes an efficient framework for conducting reliability analysis and reliability-based design(RBD)of tunnel face stability in spatially variable soil *** three-dimensional(3D)rotational failure mechanism of the tunnel face is extended to account for the soil spatial variability,and a probabilistic framework is established by coupling the extended mechanism with the improved Hasofer-Lind-Rackwits-Fiessler recursive algorithm(iHLRF)as well as its inverse analysis *** proposed framework allows for rapid and precise reliability analysis and RBD of tunnel face *** demonstrate the feasibility and efficacy of the proposed framework,an illustrative case of tunnelling in frictional soils is presented,where the soil's cohesion and friction angle are modelled as two anisotropic cross-correlated lognormal random *** results show that the proposed method can accurately estimate the failure probability(or reliability index)regarding the tunnel face stability and can efficiently determine the required supporting pressure for a target reliability index with soil spatial variability being taken into ***,this study reveals the impact of various factors on the support pressure,including coefficient of variation,cross-correlation between cohesion and friction angle,as well as autocorrelation distance of spatially variable soil *** results also demonstrate the feasibility of using the forward and/or inverse first-order reliability method(FORM)in high-dimensional stochastic *** is hoped that this study may provide a practical and reliable framework for determining the stability of tunnels in complex

关键词： Limit analysis Tunnel face stability Spatial variability HLRF algorithm Inverse reliability method

Active molecule-based theranostic agents for tumor vasculature normalization and antitumor efficacy

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Chinese Chemical Letters 2024年第8期35卷 229-234页

作者： Jin Wang Xiaoyan Pan Junyu zhang Qingqing zhang Yanchen Li Weiwei guo Jie zhang School of Pharmacy Health Science CenterXi’an Jiaotong UniversityXi’an 710061China Center of Advanced Pharmaceuticals and Biomaterials State Key Laboratory of Natural MedicineChina Pharmaceutical UniversityNanjing 210009China

Tumor vascular normalization has emerged as a promising strategy for synergistic therapy *** on the strategy of“fluorescence turn on-controllable release”,a novel bifunctional candidate was con-structed based on previous developed vascular normalization inducer QDAU5,which could self-assemble to form functional enzyme infrared QDAU5 nanoparticles(FEIRQ NPs).Subsequently,biological evaluation demonstrated that the FEIRQ NPs could induce ferroptosis,endoplasmic reticulum stress,and antigen pre-conditioning and maturation of dendritic cells and CD8^(+)T cells,leading to excellent antitumor efficacy in the absence of cytotoxic ***,FEIRQ NPs show high fluorescence intensity upon expo-sure to theβ-galactosidase(β-Gal)enzyme expressed in ovarian cancer,enabling real-time monitoring of therapeutic ***,our findings suggest a prospering strategy to early diagnosis and efficient therapy for ovarian cancer without cytotoxicity.

关键词： Tumor vasculature normalization Diagnosis and treatment Cytotoxicity Depleting glutathione Ferroptosis Immune activation

Current observation and analysis based on mooring systems in the Andaman Sea

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Journal of Oceanology and Limnology 2024年第2期42卷 484-491页

作者： Yimeng WANG Jingsong guo Dapeng QU Zhixin zhang Chalermrat SANGMANEE Varintha VASINAMEKHIN Binghuo guo First Institute of Oceanography and Key Laboratory of Marine Science and Numerical ModelingMinistry of Natural ResourcesQingdao 266061China Laboratory for Regional Oceanography and Numerical Modeling Pilot National Laboratory for Marine Science and Technology(Qingdao)Qingdao 266237China Shandong Key Laboratory of Marine Science and Numerical Modeling Qingdao 266061China Phuket Marine Biological Center Department of Marine and Coastal ResourcesPhuket 83000Thailand Marine and Coastal Resources Research&Development Institute Department of Marine and Coastal ResourcesBangkok 10210Thailand

The basic structure and intraseasonal evolution of currents in the southeastern Andaman Sea was analyzed based on data collected in 2017 from two subsurface moorings(C1 and C5).Periodic variation in the upper ocean currents of the Andaman Sea was investigated by combining observational and satellite *** observations show that rapid changes of current speed and direction occurred in May and June,with a significant increase in current velocity at the C1 *** the second half of the year,southward flow dominated at the C1 mooring,and alternating northward and southward flows were evident at the C5 mooring during the same period but the northward flow prevailed in boreal *** addition,analysis of the power spectra of the upper currents revealed that the tidal period at both moorings is primarily semidiurnal with weaker energy than that of the low-frequency *** upper ocean currents at the C1 and C5 moorings exhibited intraseasonal variation of 30-60 d and 120 d,while the zonal current at the C1 mooring exhibited a notable period of approximately 180 *** analysis indicated that the variability of currents in the Andaman Sea is influenced primarily by equatorial Kelvin waves and Rossby wave ***,our results suggest that equatorial Kelvin waves from the eastern Indian Ocean entered the Andaman Sea in the form of Wyrtki Jets and propagated primarily along two distinct pathways during the observation *** addition to coastal boundary Kelvin waves,it was found that a branch of the Wyrtki Jet that directly enters the Andaman Sea and flows northward along the slope of the continental shelf,and reflected Rossby wave packets by topography.

关键词： mooring observation Wyrtki Jet Rossby waves intraseasonal variation

C_(60) as a metal-free catalyst for lithium-oxygen batteries

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Nano Research 2024年第5期17卷 3982-3987页

作者： Xinxin zhang Jiaming Tian Yu Wang Shaohua guo Yafei Li Jiangsu Collaborative Innovation Centre of Biomedical Functional Materials School of Chemistry and Materials ScienceNanjing Normal UniversityNanjing 210023China College of Engineering and Applied Sciences Jiangsu Key Laboratory of Artificial Functional MaterialsNational Laboratory of Solid State MicrostructuresCollaborative Innovation Center of Advanced MicrostructuresFrontiers Science Center for Critical Earth Material CyclingNanjing UniversityNanjing 210023China

Carbon materials have shown significant potential as catalysts for lithium-oxygen batteries(LOBs).However,the intrinsic carbon sites are typically inert,necessitating extensive modifications and resulting in a limited density of active *** we present C_(60) as a metal-free cathode catalyst for LOBs,using density functional theory calculations and experimental *** lithiation reactions on the pristine carbon sites of C_(60) are energetically favorable due to its curvedπ-conjugation over the pentagon-hexagon *** kinetic analysis specifically reveals low energy barriers for Li_(2)O_(2) decomposition and Li diffusion on C_(60).Consequently,C_(60) exhibits significantly higher catalytic activity than typical carbon materials such as graphene and carbon *** electrochemical measurements validate the predictions,notably demonstrating that the intrinsic activity of C_(60) is comparable to that of noble metals.

关键词： lithium-oxygen batteries C_(60) density functional theory(DFT)calculations metal-free cathode

Bioinspired metal-organic framework nanozyme reinforced with thermosensitive hydrogel for regulating inflammatory responses in Parkinson’s disease

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Nano Research 2024年第2期17卷 858-865页

作者： Xiaowan Fan Tao zhang Xin ding Yushuo Gu Qing Li Wei Jiang Kelong Fan Nanozyme Medical Center Academy of Medical ScienceZhengzhou UniversityZhengzhou 450001China Department Central-China Branch of National Center for Cardiovascular DiseasesHean Cardiovascular Disease CenterFuwai Central-China HospitalCentral China Fuwai Hospital of Zhengzhou UniversityZhengzhou 450046China Application Center for Precision Medicine the Second Affiliated Hospital of Zhengzhou UniversityZhengzhou 450052China CAS Engineering Laboratory for Nanozyme Key Laboratory of Protein and Peptide PharmaceuticalsInstitute of BiophysicsChinese Academy of SciencesBeijing 100101China University of Chinese Academy of Sciences Beijing 101408China Department of General Surgery Strategic Support Force Medical CenterBeijing 100101China Department of Anesthesiology Pain and Perioperative MedicineThe First Affiliated Hospital of Zhengzhou UniversityZhengzhou 450052China

Parkinson’s disease(PD)is a prevalent neurodegenerative disorder accompanied by movement disorders and neuroinflammatory ***-inflammatory intervention to regulate oxidative stress in the brain is beneficial for managing ***,traditional natural antioxidants have failed to meet the clinical treatment demands due to insufficient activity and ***,Cu-doping zeolite imidazolate framework-8(ZIF-8)nanozyme is designed to simulate Cu/Zn superoxide dismutase(SOD)by biomimetic *** nanozyme composite is then integrated into thermosensitive hydrogel(poly(lactic-co-glycolic acid)-poly(ethylene glycol)-poly(lactic-co-glycolic acid)(PLGA-PEG-PLGA))to form an effective antioxidant system(Cu-ZIF@Hydrogel).The thermosensitive hydrogel incorporating nanozymes demonstrate distinct viscoelastic properties aimed at enhancing local nanozyme adhesion,prolonging nanozyme retention time,and modulating antioxidant activity,thus significantly improving the bioavailability of *** the cellular and animal levels of PD,we find that Cu-ZIF@Hydrogel bypass the blood-brain barrier and efficiently accumulate in the nerve ***,the Cu-ZIF@Hydrogel significantly alleviate the PD’s behavioral and pathological symptoms by reducing the neuroinflammatory levels in the lesion ***,the hydrogel-incorporating nanozyme system holds great potential as a simple and reliable avenue for managing PD.

关键词： bioinspired nanozyme thermosensitive hydrogel Parkinson’s disease oxidative stress neuroinflammatory