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Acta Mathematica Sinica,English Series 2024年第9期40卷 2091-2152页

作者： Qi An guan zhi Tong MI Zheng YUAN School of Mathematical Sciences Peking UniversityBeijing 100871P.R.China School of Mathematics and Statistics Beijing Jiaotong UniversityBeijing 100044P.R.China Institute of Mathematics Academy of Mathematics and Systems ScienceChinese Academy of SciencesBeijing 100190P.R.China

In this article,we consider a modified version of minimal L^(2) integrals on sublevel sets of plurisubharmonic functions related to modules at boundary points,and obtain a concavity property of the modified *** applications,we give characterizations for the concavity degenerating to linearity on open Riemann surfaces and on fibrations over open Riemann surfaces.

关键词： Minimal L^(2)integrals plurisubharmonic functions boundary points weakly pseudoconvex Kähler manifold

Degradation and biocompatibility of one-step electrodeposited magnesium thioctic acid/magnesium hydroxide hybrid coatings on ZE21B alloys for cardiovascular stents

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Journal of Magnesium and Alloys 2024年第1期12卷 120-138页

作者： Zhao-Qi Zhang Bing-zhi Li Pei-Duo Tong Shao-Kang guan Li Wang Zheng-Hui Qiu Cun-Guo Lin Rong-Chang zeng School of Material Science and Engineering&Henan Key Laboratory of Advanced Magnesium Alloy&Key Laboratory of Materials Processing and Mold Technology(Ministry of Education) Zhengzhou University100 Science RoadZhengzhou 450001China State Key Laboratory for Marine Corrosion and Protection Luoyang Ship Material Research InstituteQingdao 266101China Corrosion Laboratory for Light Metals College of Material Science and EngineeringShandong University of Science and TechnologyQingdao 266590China

Constructing a functional hybrid coating appears to be a promising strategy for addressing the poor corrosion resistance and insufficient endothelialization of Mg-based ***,the steps for preparing composite coatings are usually complicated and ***,a novel composite coating,composed of bioactive magnesium thioctic acid(MTA)layer formed by deposition and corrosion-resistant magnesium hydroxide(Mg(OH)_(2))layer grown in situ,is simply fabricated on ZE21B alloys via one-step *** electron microscopy(SEM)shows that the electrodeposited coating has a compact and uniform *** the high adhesion of the MTA/Mg(OH)_(2)hybrid coating is also confirmed by the micro-scratch *** test,scanning kelvin probe(SKP),and hydrogen evolution measurement indicate that the hybrid coating effectively reduces the degradation rate of Mg *** experiment and cell culture trial detect that the composite coating is of fine ***,the preparation mechanism of MTA/Mg(OH)_(2)hybrid coatings is discussed and *** coating shows a great potential application for cardiovascular stents.

关键词： Magnesium alloy Corrosion resistance Hybrid coating Endothelialization Biocompatibility

Switching,explosion,and chaos of multi-wavelength soliton states in ultrafast fiber lasers

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Science China(Physics,Mechanics & Astronomy) 2024年第7期67卷 82-90页

作者： zhi-zeng Si Yue-Yue Wang Chao-Qing Dai College of Optical Mechanical and Electrical EngineeringZhejiang A&F UniversityLin’an 311300China

Because of the complexity and difficulty of realizing a multi-wavelength soliton state,reports on its internal dynamic characteristics are *** this study,the switching and periodic soliton explosion processes of the multi-wavelength soliton state in a negative dispersion passively mode-locked fiber laser are *** generation of the multi-wavelength soliton state undergoes the process of noise,oscillation,and stable mode-locking,and the splitting and annihilation of solitons with different group velocities directly impact the generation and disappearance of three *** and negative dispersion lead to different group velocities of *** presence and displacement of solitons with different group velocities cause soliton collisions,which lead to soliton explosions.A soliton experiences relative phase oscillation,chaos,and oscillation,as well as convergence and separation before and after an *** an increase in parameters related to pump power,single-soliton oscillation,multi-wavelength solitons,and chaos are found in experiments and simulations,proving the relevance and reliability between simulation and experimental *** work promotes the dynamical study of multi-soliton collisions in nonlinear science and the development of chaos theory in multi-comb lasers.

关键词： multi-wavelength fiber laser soliton explosion chaos state switching real-time dynamics

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半刚性基层材料抗冲刷性能的研究

混凝土 2008年第3期 48-50页

作者：关增智中铁九局集团有限公司辽宁沈阳110036

半刚性基层材料的抗冲刷性能是评价路面路用性能的一项重要指标,对整个路面特别是沥青路面的强度、使用质量和使用寿命都有十分重要的影响。针对半刚性基层材料常见的冲刷病害,在分析其形成机理的基础上,在室内利用冲刷试验仪研究抗冲... 详细信息

半刚性基层材料的抗冲刷性能是评价路面路用性能的一项重要指标,对整个路面特别是沥青路面的强度、使用质量和使用寿命都有十分重要的影响。针对半刚性基层材料常见的冲刷病害,在分析其形成机理的基础上,在室内利用冲刷试验仪研究抗冲刷性能的影响因素,提出了利用10 min内冲刷速率作为半刚性基层材料抗冲刷性能的评价指标。

关键词：冲刷试验半刚性基层指标级配

Flexible tuning of multifocal holographic imaging based on electronically controlled metasurfaces

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Photonics Research 2024年第1期12卷 61-69页

作者： OWEN zeng CHENXIA LI BO FANG zhi HONG XUFENG JING Institute of Optoelectronic Technology China Jiliang UniversityHangzhou 310018China Centre for THz Research China Jiliang UniversityHangzhou 310018China College of Metrology&Measurement Engineering China Jiliang UniversityHangzhou 310018China

Programmable hyper-coded holography has the advantage of being programmable as well as being flexibly *** coded metamaterials with excellent electromagnetic modulation capability and the ability to control the phase to modulate the spatial radiation field through external excitation in the form of switching can be used to realize low-cost digital *** design a 1-bit encoded programmable metasurface,which is electrically connected to control the PIN diode in the switching state and to switch the condition of each metasurface cell between“0”and“1.”Using the designed programmable metasurface,we can randomly encode the cell structure to realize single-focus focusing,multi-focusing,and simple holographic letter *** on the nonlinear holographic model,we employ the Gerchberg-Saxton improvement algorithm to modulate the energy distribution at the focus by adjusting the phase ***,we introduce the Fourier convolution principle to regulate the holographic imaging focus flexibly.

关键词： holographic letter excitation

Non-monotonic behavior of jam probability and stretched exponential distribution in pedestrian counterflow

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CHINESE PHYSICS B 2024年第9期33卷 259-266页

作者： Chen, Ze-Hao Wu, zhi-Xi guan, Jian-Yue guangxi Normal Univ Guilin 541004 Peoples R China Lanzhou Univ Lanzhou Ctr Theoret Phys Key Lab Theoret Phys Gansu Prov Lanzhou 730000 Peoples R China Lanzhou Univ Key Lab Quantum Theory & Applicat Minist Educ Lanzhou 730000 Peoples R China

We adopt a floor field cellular automata model to study the statistical properties of bidirectional pedestrian flow moving in a straight corridor. We introduce a game-theoretic framework to deal with the conflict of multiple pedestrians trying to move to the same target location. By means of computer simulations, we show that the complementary cumulative distribution of the time interval between two consecutive pedestrians leaving the corridor can be fitted by a stretched exponential distribution, and surprisingly, the statistical properties of the two types of pedestrian flows are affected differently by the flow ratio, i.e., the ratio of the pedestrians walking toward different directions. We also find that the jam probability exhibits a non-monotonic behavior with the flow ratio, where the worst performance arises at an intermediate flow ratio of around 0.2. Our simulation results are consistent with some empirical observations, which suggest that the peculiar characteristics of the pedestrians may attributed to the anticipation mechanism of collision avoidance.

关键词： traffic and crowd dynamics evolutionary game theory 02.50.Le 45.70.Vn FLOW CHARACTERISTICS DYNAMICS

Multi-scale data joint inversion of minerals and porosity in altered igneous reservoirs—A case study in the South China Sea

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Petroleum Science 2024年第1期21卷 206-220页

作者： Xin-Ru Wang Bao-zhi Pan Yu-Hang Guo Qing-Hui Wang Yao guan College of Geo-exploration Science and Technology Jilin UniversityChangchun130046JilinChina Research Institute CNOOC Ltd.-ShenzhenShenzhen518000GuangdongChina

There are abundant igneous gas reservoirs in the South China Sea with significant value of research,and lithology classification,mineral analysis and porosity inversion are important links in reservoir ***,affected by the diverse lithology,complicated mineral and widespread alteration,conventional logging lithology classification and mineral inversion become considerably *** the same time,owing to the limitation of the wireline log response equation,the quantity and accuracy of minerals can hardly meet the exploration requirements of igneous *** overcome those issues,this study takes the South China Sea as an example,and combines multi-scale data such as micro rock slices,petrophysical experiments,wireline log and element cutting log to establish a set of joint inversion methods for minerals and porosity of altered igneous ***,we define the lithology and mineral characteristics through core slices and mineral data,and establish an igneous multi-mineral volumetric *** we determine element cutting log correction method based on core element data,and combine wireline log and corrected element cutting log to perform the lithology classification and joint inversion of minerals and ***,it is always difficult to determine the elemental eigenvalues of different minerals in *** paper uses multiple linear regression methods to solve this ***,an integrated inversion technique for altered igneous formations was *** results show that the corrected element cutting log are in good agreement with the core element data,and the mineral and porosity results obtained from the joint inversion based on the wireline log and corrected element cutting log are also in good agreement with the core data from X-ray *** results demonstrate that the inversion technique is applicable and this study provides a new direction for the mineral inversion research of altered igneous formation

关键词： Joint inversion Altered igneous rock Element correction method Lithology identification Multi mineral volume model

Lyme Borreliosis-associated Risk Factors in Residents of Beijing Suburbs: a Preliminary Case-control Study

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Biomedical and Environmental Sciences 2014年第10期27卷 807-810页

作者： DOU Xiang Feng LYU Yan Ning JIANG Yi LIN Chang Ying TIAN Li Li WANG Quan Yi YANG Yu Song LI Chao SUN Yu Lan guan zeng zhi ZHANG Xiu Chun LI Xin Yu Institute for Infectious and Endemic Diseases Control Beijing Center for Disease Prevention and Control State Key Laboratory for Infectious Diseases Prevention and Control National Institute of Communicable Disease Control & Prevention Chinese Center of Disease Control & Prevention Collaborative Innovation Center for Diagnosis and Treatment of Infectious Diseases Miyun Country Center for Disease Prevention and Control Huairou District Center for Disease Prevention and Control

A population-based case-control study was conducted to evaluate the relative fac^tors in the environments, agricultural works, outdoor activities, and the effectiveness of Lyme borreliosis （LB）- associated personal protective measure.c; in Beijing. Thirty-four cases and 272 controls were personally interviewed by well-trained interviewers. Venous blood samples were taken from eac：h subject. Sowing or harvesting in summer （OR=2.571, 95% CI： 1.109-5.962）, living in house with weeding in the yard （OR=2.247, 95% CI： 1.062-4.755）.

关键词： a Preliminary Case-control Study Lyme Borreliosis-associated Risk Factors in Residents of Beijing Suburbs

Crystalline carbon nitride with in-plane built-in electric field accelerates carrier separation for excellent photocatalytic hydrogen evolution

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Chinese Chemical Letters 2024年第4期35卷 160-165页

作者： Wengao zeng Yuchen Dong Xiaoyuan Ye Ziying Zhang Tuo Zhang Xiangjiu guan Liejin Guo International Research Center for Renewable Energy State Key Laboratory of Multiphase Flow in Power EngineeringXi'an Jiaotong UniversityXi'an 710049China

Achieving a high carrier migration efficiency by constructing built-in electric field is one of the promising approaches for promoting photocatalytic activity. Herein, we have designed a donor-acceptor(D-A) crystalline carbon nitride(APMCN) with 4-amino-2,6-dihydroxypyrimidine(AP) as electron donor, in which the pyrimidine ring was well embedded in the heptazine ring via hydrogen-bonding effect during hydrothermal process. The APMCN shows superior charge-transfer due to giant built-in electric field(5.94times higher than pristine carbon nitride), thereby exhibiting excellent photocatalytic H_(2) evolution rate(1350 μmol/h) with a high AQY(62.8%) at 400 nm. Mechanistic analysis based on detailed experimental investigation together with theoretical analysis reveals that the excellent photocatalytic activity is attributed to the promoted charge separation by the giant internal electric field originated from the D–A structure.

关键词： Crystalline carbon nitride Built-in electric field Donor-acceptor structure Photocatalysis Hydrogen production

A Low Cost, Green Sustainable and Biodegradable Biomass-based Fluorine-free Water and Oil Repellent

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Chinese Journal of Polymer Science 2024年第4期42卷 480-491页

作者： zhi-Wei Shen Shu-Feng Hu Chen zeng Wei-Qing Kong Mei-Fang Zhu State Key Laboratory for Modification of Chemical Fibers&Polymer Materials College of Materials Science and EngineeringDonghua UniversityShanghai201620China State Key Laboratory of Pulp and Paper Engineering School of Light Industry and EngineeringSouth China University of TechnologyGuangzhou510630China

With the global ban on plastics intensifying, the substitution of plastic with paper has garnered increasing attention. However, the inadequate water and oil repellency of pulp molding hinders its practical applications. Currently, the common method to enhance the oil and water repellency of pulp molding is by adding fluorinated water and oil repellents. Nevertheless, fluorinated compounds are environmentally and physiologically harmful. Therefore, the development of fluorine-free, water and oil repellent alternatives is crucial. In this study, chitosan and stearic acid were utilized as the first and second layers of the oil and water repellent coatings, respectively. The coated samples exhibited favorable water repellency, with a water contact angle of 116.4°, and excellent oil repellency, achieving a 12/12 rating on the kit scale. Importantly, the samples did not exhibit any leakage after being soaked in hot water and hot oil at 95±5℃ for 30 min, demonstrating remarkable performance as a barrier against hot water and oil. Moreover, the coated samples displayed outstanding mechanical properties, thermal stability, biodegradability, and recyclability. The approach presented in this study is simple, cost-effective, environmentally friendly, and represents a promising technique for producing fluoride-free, oil-and water-resistant pulp molding products.

关键词： Biomass Fluoride-free Oil-andwater-resistant Plasticfree