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Editorial:special topic on heterojunction in photocatalysts

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Science China Materials 2024年第2期67卷 379-381页

作者： Jiaguo Yu Xin Li Junwei Fu Kai dai Laboratory of Solar Fuel Faculty of Materials Science and ChemistryChina University of GeosciencesWuhan 430078China Institute of Biomass Engineering Key Laboratory of Energy Plants Resource and UtilizationMinistry of Agriculture and Rural AffairsSouth China Agricultural UniversityGuangzhou 510642China Hunan Joint International Research Center for Carbon Dioxide Resource Utilization State Key Laboratory of Powder MetallurgySchool of PhysicsCentral South UniversityChangsha 410083China Anhui Province Key Laboratory of Pollutant Sensitive Materials and Environmental Remediation College of Physics and Electronic InformationHuaibei Normal UniversityHuaibei 235000China

To suppress the recombination of photogenerated electron and hole in single photocatalysts,an important method is to design heterojunction by combining two *** method has widely used to enhance the photocatalytic performance of the *** the begining,most people use type-Ⅱcharge carrier transfer mechanism to explain the emhanced activity of the composite semiconductors.

关键词： composite heterojunction method

A multi-enzymatic cascade reaction for the synthesis of bioactive C-oligosaccharides

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Chinese Chemical Letters 2024年第6期35卷 451-455页

作者： Kebo Xie Qian Zhang Fei Ye Jungui dai State Key Laboratory of Bioactive Substance and Function of Natural Medicines CAMS Key Laboratory of Enzyme and Biocatalysis of Natural Drugs and NHC Key Laboratory of Biosynthesis of Natural ProductsInstitute of Materia MedicaChinese Academy of Medical Sciences and Peking Union Medical CollegeBeijing 100050China

C-Oligosaccharides are rare in nature and possess diverse ***,their chemical synthesis faces many *** this work,enzymatic introduction of C-linked sugar chains to target aglycones was successfully achieved by multi-enzymatic cascade reactions.A C-glycosyltransferase from Aloe barbadensis was employed to introduce the first C-linked glucose and then a cyclomaltodextrin glucanotransferase from Bacillus licheniformis was used to extend the sugar chain.A total of twenty C-oligosaccharides with 2.6 sugars were synthesized from scale-up reactions and exhibited good water solubility and sodium-dependent glucose transporter 2.SGLT2.inhibitory ***,a glucoamylase was used to control the length of the sugar chain and the C-maltosides were efficiently *** findings not only expanded the structural diversity of C-oligosaccharides,but also provided a strategy for the modification of C-glycoside drugs to improve the druggability.

关键词： C-Oligosaccharides C-Glycosyltransferase Cyclomaltodextrin glucanotransferase Glucoamylase Enzymatic synthesis SGLT2.inhibitory activity

In-situ construction of MnCO3@CNTs nanosheets for high-capacity aqueous zinc ion batteries

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Science China Technological Sciences 2024年第11期67卷 3394-3404页

作者： LI Tao dai GeLiang LIU SiYu ZHANG JingYu SUN AoKui School of Packaging and Materials Engineering Hunan University of Technology

Owing to severe agglomeration of manganese carbonate（MnCO3） during its synthesis,it exhibits rapid decay cycle performance when used as a cathode material in aqueous zinc ion *** overcome this drawback,we synthesized a MnCO3material with carbon nanotubes（CNTs）(i.e.,MnCO3@CNTs) via a one-step solvothermal method using a hybrid modification ***3nanospheres were grown in-situ on a two-dimensional（2.） plane that was orderly interwoven by tubular single fibers of carbon to form a leaf-like nanosheet *** surface area of the MnCO3@CNTs material was enlarged enormously through the special nanosheet structure,and its stability was improved by the supporting structure of the *** a result,the MnCO3@CNTs exhibited a discharge capacity of 2.7.6 mAh g-1at a current density of 0.1 A *** energy storage mechanism of MnCO3@CNTs was further explored using a series of electrochemical kinetic analyses and ex-situ characterization *** modification method not only broadens the application field of MnCO3,but also provides the possibility of modifying more cathode materials.

关键词： manganese carbonate cathode materials aqueous zinc ion batteries energy storage mechanism

Non-Gaussian feature of the output field from a double qubit-cavity ultrastrong coupling system

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Communications in Theoretical Physics 2024年第7期76卷 30-36页

作者： Sheng-wen Xu Shi-yu dai Teng Zhao Center for Quantum Science and Technology Jiangxi Normal UniversityNanchang 330022China

We investigate the non-Gaussian feature of radiation in a circuit quantum electrodynamics(QED)system where two qubits are strongly coupled to a single-mode *** the regime of ultrastrong coupling(USC),the rotating-wave approximation is not valid,and the Rabi Hamiltonian contains counter-rotating wave terms,leading to level crossing and avoided crossings in the energy *** further analyze the intensity-amplitude correlation of the output field in these two novel *** the USC regime,the creation and annihilation operators in the correlation function are replaced,allowing for the identification of non-Gaussian features in the output *** findings reveal that despite the absence of squeezing effects in the output light,significant non-Gaussian characteristics are ***,we demonstrate that as the driving or coupling strength increases,the non-Gaussian features of the output field become more *** suggests that USC systems hold broad potential applications in the realms of nonlinear optics and the generation of non-Gaussian states.

关键词： ultrastrong coupling non-Gaussian intensity-amplitude correlation

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

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Photonics Research 2024年第8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 TelecommunicationsBeijing 100876China School of Electronic Engineering Beijing University of Posts and TelecommunicationsBeijing 100876China

Advancements in microwave photonics have yielded novel approaches for generating high-purity microwave *** 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 ***,we present a COEO featuring ultralow phase noise,flexible tuning capability,and high *** 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 *** 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 *** 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 1.2. MHz,and fractional frequency stability below 6.1×10^(-12.at 1 s averaging time when locked to a *** 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： optoelectronic tuning amplifier

Scraping therapy for knee osteoarthritis: a systematic review and Meta-analysis

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Journal of Traditional Chinese Medicine 2024年第4期44卷 633-641页

作者： CHEN Dandan JIN Qianhong SHEN Yuanjuan WANG Qing dai Zhengxiang School of Nursing Guangxi University of Chinese MedicineNanning 530200China School of Nursing Nanjing University of Chinese MedicineNanjing 210023China General Surgery Department Jiangsu Province Hospital of Chinese MedicineNanjing 210004China Hospital Infection Control Office Jiangsu Province Hospital of Chinese MedicineNanjing 210004China

OBJECTIVE:To systematically evaluate the efficacy of scraping therapy on knee osteoarthritis(KOA).METHODS:A computerized search was conducted in several databases,including PubMed,Web of Science,Cochrane Library,China National Knowledge Infrastructure Database,China Science and Technology Journal Database,Wanfang,and Chinese BioMedical Literature Database,from the establishment date of these databases to April 9,*** controlled trials(RCTs)on scraping therapy for KOA were collected in accordance with the“Participants-Intervention-Control-Outcome-Study design”*** methodological evaluation of the included studies was carried out using RoB 2.0,and Meta-analysis was conducted using *** Grades of Recommendations Assessment,Development and Evaluation(GRADE System)was applied to grade the quality of ***:A total of 12.RCTs with 997 subjects were included in the *** indicated that compared with the control group,the scraping therapy treatment group exhibited increased Lysholm scores[mean difference(MD)=4.96,95%confidence intervals(CI)(3.18,6.74),P2.12.78),P=0.0002.and decreased visual analog scale scores[MD=-2.11,95%CI(-3.79,-0.44),P=0.01]and Western Ontario and McM aster University Osteoarthritis Index scores[MD=-6.77,95%CI(-8.99,-4.56),P<0.00001)].The quality of evidence obtained in this Meta-analysis was low according to the GRADE ***:The available evidence suggests that scraping therapy may have certain clinical efficacy in the treatment of ***,further high-quality RCTs are needed to confirm the findings.

关键词： osteoarthritis,knee scraping Meta-analysis systematicreview

A seismic elastic moduli module for the measurements of low-frequency wave dispersion and attenuation of fluid-saturated rocks under different pressures

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Petroleum Science 2024年第1期21卷 162-181页

作者： Yan-Xiao He Shang-Xu Wang Gen-Yang Tang Chao Sun hong-Bing Li San-Yi Yuan Xian Wei Li-Deng Gan Xiao-Feng dai Qiang Ge Peng-Peng Wei Hui-Qing Zhang National Key Laboratory of Petroleum Resources and Engineering CNPC Key Lab of Geophysical ExplorationCollege of GeophysicsChina University of Petroleum(Beijing)Beijing102249China School of Resources and Geosciences China University of Mining and TechnologyXuzhou221116JiangsuChina Research Institute of Petroleum Exploration and Development CNPCBeijing100083China Beijing Vocational College of Labour and Social Security Beijing100029China PetroChina Dagang Oilfield Exploration and Development Research Institute CNPCTianjin300280China

Knowledge about the seismic elastic modulus dispersion,and associated attenuation,in fluid-saturated rocks is essential for better interpretation of seismic observations taken as part of hydrocarbon identification and time-lapse seismic surveillance of both conventional and unconventional reservoir and overburden performances.A Seismic Elastic Moduli Module has been developed,based on the forced-oscillations method,to experimentally investigate the frequency dependence of Young's modulus and Poisson's ratio,as well as the inferred attenuation,of cylindrical samples under different confining pressure *** with three standard samples showed that the measured elastic moduli were consistent with the published data,indicating that the new apparatus can operate reliably over a wide frequency range of f∈[1-2.00,10^(6)]*** Young's modulus and Poisson's ratio of the shale and the tight sandstone samples were measured under axial stress oscillations to assess the frequency-and pressure-dependent *** dry condition,both samples appear to be nearly frequency independent,with weak pressure dependence for the shale and significant pressure dependence for the *** particular,it was found that the tight sandstone with complex pore microstructure exhibited apparent dispersion and attenuation under brine or glycerin saturation conditions,the levels of which were strongly influenced by the increased effective *** addition,the measured Young's moduli results were compared with the theoretical predictions from a scaled poroelastic model with a reasonably good agreement,revealing that the combined fluid flow mechanisms at both mesoscopic and microscopic scales possibly responsible for the measured dispersion.

关键词： Low-frequency measurements Dispersion and attenuation Rock physics Fluid flow

Dynamic plugging regulating strategy of pipeline robot based on reinforcement learning

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Petroleum Science 2024年第1期21卷 597-608页

作者： Xing-Yuan Miao hong Zhao College of Mechanical and Transportation Engineering China University of PetroleumBeijing102249China

Pipeline isolation plugging robot (PIPR) is an important tool in pipeline maintenance operation. During the plugging process, the violent vibration will occur by the flow field, which can cause serious damage to the pipeline and PIPR. In this paper, we propose a dynamic regulating strategy to reduce the plugging-induced vibration by regulating the spoiler angle and plugging velocity. Firstly, the dynamic plugging simulation and experiment are performed to study the flow field changes during dynamic plugging. And the pressure difference is proposed to evaluate the degree of flow field vibration. Secondly, the mathematical models of pressure difference with plugging states and spoiler angles are established based on the extreme learning machine (ELM) optimized by improved sparrow search algorithm (ISSA). Finally, a modified Q-learning algorithm based on simulated annealing is applied to determine the optimal strategy for the spoiler angle and plugging velocity in real time. The results show that the proposed method can reduce the plugging-induced vibration by 19.9% and 32.7% on average, compared with single-regulating methods. This study can effectively ensure the stability of the plugging process.

关键词： Pipeline isolation plugging robot Plugging-induced vibration Dynamic regulating strategy Extreme learning machine Improved sparrow search algorithm Modified Q-learning algorithm

Ultrafast photoemission electron microscopy:A multidimensional probe of nonequilibrium physics

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Chinese Physics B 2024年第3期33卷 24-57页

作者：戴亚南 Department of Physics Southern University of Science and Technology (SUSTech)Shenzhen 518055China Quantum Science Center of Guangdong-hong Kong-Macao Greater Bay Area (Guangdong) Shenzhen 518045China

Exploring the realms of physics that extend beyond thermal equilibrium has emerged as a crucial branch of condensed matter physics *** aims to unravel the intricate processes involving the excitations,interactions,and annihilations of quasi-and many-body particles,and ultimately to achieve the manipulation and engineering of exotic non-equilibrium quantum phases on the ultrasmall and ultrafast spatiotemporal *** the inherent complexities arising from many-body dynamics,it therefore seeks a technique that has efficient and diverse detection degrees of freedom to study the underlying *** combining high-power femtosecond lasers with real-or momentum-space photoemission electron microscopy(PEEM),imaging excited state phenomena from multiple perspectives,including time,real space,energy,momentum,and spin,can be conveniently achieved,making it a unique technique in studying physics out of *** this context,we overview the working principle and technical advances of the PEEM apparatus and the related laser systems,and survey key excited-state phenomena probed through this surface-sensitive methodology,including the ultrafast dynamics of electrons,excitons,plasmons,spins,etc.,in materials ranging from bulk and nano-structured metals and semiconductors to low-dimensional quantum *** this review,one can further envision that time-resolved PEEM will open new avenues for investigating a variety of classical and quantum phenomena in a multidimensional parameter space,offering unprecedented and comprehensive insights into important questions in the field of condensed matter physics.

关键词： ultrafast photoemission electron microscopy ultrafast momentum microscopy excited state physics