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Photonics Research 2024年第7期12卷 1395-1409页

作者： XIMING LI RUI XU XIAOFENG SUN YUAN zhao zhao YANG GUOHONG DU College of Electronic Engineering Chengdu University of Information TechnologyChengdu 610225China

Programmable metasurfaces have received a great deal of attention due to their ability to dynamically manipulate electromagnetic(EM) waves. Despite the rapid growth, most of the existing metasurfaces require manual control to switch among different functionalities, which poses severe limitations on practical applications. Here, we put forth an intelligent metasurface that has self-adaptive EM functionality switching in broadband without human participation. It is equipped with polarization discrimination antennas(PDAs) and feedback components to automatically adjust functionalities for the different incident polarization information.

关键词： equipped adjust polarization

Remarkable enhancement of gas selectivity on organosilica hybrid membranes using urea-modulated metal-organic framework nanoparticles

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Frontiers of Chemical Science and Engineering 2024年第2期18卷 83-92页

作者： Yayun zhao Dechuan zhao Chunlong Kong Yichao Lin Xuezhen Wang Liang Chen Key Laboratory of Advanced Fuel Cells and Electrolyzers Technology of Zhejiang Province Ningbo Institute of Materials Technology and EngineeringChinese Academy of SciencesNingbo 315201China University of Chinese Academy of Sciences Beijing 100049China Collaboration Innovation Center for Tissue Repair Material Engineering Technology China West Normal UniversityNanchong 637009China

Metal-organic framework/organosilica hybrid membranes on tubular ceramic substrates have shown great potential for the implementation of membrane technology in practical gas separation projects due to their higher permeance compared to commercial ***,the selectivities of the reported membranes are ***,we have incorporated urea-modulated metal-organic frameworks into organosilica membranes to greatly enhance its separation *** urea-modulated metal-organic frameworks exhibit less-defined edges of crystallographic facets and high defect *** can be well-dispersed in the organosilica layer,which substantially suppresses the interfacial defects between metal-organic frameworks and organosilica,which is beneficial for improving the selectivity of membranes for gas *** results have shown that the enhanced ideal selectivity of H_(2)/CH_(4) was 165 and that of CO_(2)/CH_(4) was 43,with H_(2) permeance of about 1.25×10^(−6) mol·m^(−2)·s^(−1)·Pa^(−1) and CO_(2) permeance of 3.27×10^(−7) mol·m^(−2)·s^(−1)·Pa^(−1) at 0.2 MPa and 25℃.In conclusion,the high level of hybrid membranes can be used to separate H_(2)(or CO_(2))from the binary gas mixture H_(2)/CH_(4)(or CO_(2)/CH_(4)),which is important for gas separation in practical ***,the simple and feasible modulation of metal-organic framework is a promising strategy to tune different metal-organic frameworks for membranes according to the actual demands.

关键词： ZIF-8 nanocrystals urea organosilica hybrid membrane enhanced separation performance

Singularity analysis and avoidance for an SSRMS-type reconfigurable space manipulator with a non-spherical wrist and two lockable passive telescopic links

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Chinese Journal of Aeronautics 2024年第8期37卷 435-459页

作者： Zhiyuan zhao Xiaohang YANG Yuntao LI Zichun XU Jingdong zhao Hong LIU State Key Laboratory of Robotics and System Harbin Institute of TechnologyHarbin 150001China

This study focuses on addressing kinematic singularity analysis and avoidance issues for a space station remote manipulator system(SSRMS)-type reconfigurable space *** manipulator is equipped with a non-spherical wrist and two lockable passive telescopic links(LPTLs),which enable it to have both active revolute and passive prismatic joints and operate in two distinct *** begin with the kinematic singularity analysis,the study derives the differential kinematic equations for the manipulator and identifies the dominant Jacobian matrix that causes ***,an in-depth analysis of singularities from multiple perspectives is ***,a kinematic singularity map method is proposed to capture the distribution of singularities within the reachable ***,the influence of the two LPTLs on singularities is thoroughly ***,a new method based on the matrix rank equivalence principle is introduced to determine singularity conditions,enabling the identification of all the singular configurations for the SSRMS-type reconfigurable ***,this method significantly reduces computational complexity,and the singularity conditions obtained have more concise *** the singularity avoidance problem,a novel method is developed,which simultaneously addresses the requirements of real-time performance,high precision,and the avoidance of both kinematic singularities and joint limit *** from these excellent properties,the proposed method can effectively resolve the singularity issues encountered separately by the SSRMS-type reconfigurable manipulator in its two operational *** typical simulations validate the utility of all the proposed methods.

关键词： Reconfigurable space manipulator Redundant manipulator Kinematics Singularity analysis Singularity avoidance

Tribological properties of low-temperature time-dependent pretreated graphite for mechanical seal pairs in high-speed turbopump

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Friction 2024年第2期12卷 305-318页

作者： Yangyang zhao Guoyuan ZHANG Junqian WANG He WANG Weigang zhao Qunfeng ZENG School of Mechano-Electronic Engineering Xidian UniversityXi’an 710071China Xi’an Aerospace Propulsion Institute Xi’an 710071China Key Laboratory of Education Ministry for Modern Design and Rotor-Bearing System Xi’an Jiaotong UniversityXi’an 710049China

The friction coefficient and wear rate of pretreated graphite with liquid nitrogen were obtained by using a ball-on-disk tester,and the wear of GCr15–graphite seal pairs with the low-temperature time-dependent pretreatment was discussed by comparing the wear *** results show that liquid nitrogen pretreatment can affect the hardness and interlayer spacing of *** range of the friction coefficients of pretreated graphite changes from 0.17 to *** the increase of liquid nitrogen pretreatment time,the wear mechanism of graphite would change from dominated three-body wear to adhesion *** experimental results of the mechanical seal with liquid nitrogen pretreatment show that the wear rate of stator is less than 0.00165 mm^(3)·N^(−1)·m^(−1),and the graphite shows a good low-temperature compatibility.

关键词： graphite low-temperature pretreatment mechanical seal friction and wear

An Environment‑Tolerant Ion‑Conducting Double‑Network Composite Hydrogel for High‑Performance Flexible Electronic Devices

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Nano-Micro Letters 2024年第5期16卷 352-369页

作者： Wenchao zhao Haifeng Zhou Wenkang Li Manlin Chen Min Zhou Long zhao State Key Laboratory of Advanced Electromagnetic Technology School of Electrical and Electronic EngineeringHuazhong University of Science and TechnologyWuhan 430074People’s Republic of China School of Chemistry and Chemical Engineering Huazhong University of Science and TechnologyWuhan 430074People’s Republic of China

High-performance ion-conducting hydrogels(ICHs)are vital for developing flexible electronic ***,the robustness and ion-conducting behavior of ICHs deteriorate at extreme tempera-tures,hampering their use in soft *** resolve these issues,a method involving freeze–thawing and ionizing radiation technology is reported herein for synthesizing a novel double-network(DN)ICH based on a poly(ionic liquid)/MXene/poly(vinyl alcohol)(PMP DN ICH)*** well-designed ICH exhibits outstanding ionic conductivity(63.89 mS cm^(-1) at 25℃),excellent temperature resistance(-60–80℃),prolonged stability(30 d at ambient temperature),high oxidation resist-ance,remarkable antibacterial activity,decent mechanical performance,and ***,the ICH performs effectively in a flexible wireless strain sensor,thermal sensor,all-solid-state supercapacitor,and single-electrode triboelectric nanogenerator,thereby highlighting its viability in constructing soft electronic *** highly integrated gel structure endows these flexible electronic devices with stable,reliable signal output *** particular,the all-solid-state supercapacitor containing the PMP DN ICH electrolyte exhibits a high areal specific capacitance of 253.38 mF cm^(-2)(current density,1 mA cm^(-2))and excellent environmental *** study paves the way for the design and fabrication of high-performance mul-tifunctional/flexible ICHs for wearable sensing,energy-storage,and energy-harvesting applications.

关键词： Ionic liquids Double-network hydrogels Temperature tolerance Multifunctionality Flexible electronic devices

New pimarane diterpenoids with antibacterial activity from fungus Arthrinium ***03

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Chinese Journal of Natural Medicines 2024年第4期22卷 356-364页

作者： zhao Songfeng JING Ziwei Department of Pharmacy the First Affiliated Hospital of Zhengzhou UniversityZhengzhou 450052China

A comprehensive chemical study of the endophytic fungus Arthrinium sp. ZS03, associated with Acorus tatarinowii Schott, yielded eleven pimarane diterpenoids (compounds 1–11), including seven novel compounds designated arthrinoids A–G (1–7). The determination of their structures and absolute configurations was achieved through extensive spectroscopic techniques, quantum chemical calculations of electronic circular dichroism (ECD), and single-crystal X-ray diffraction analysis. Furthermore, 7 demonstrated inhibitory activity against Klebsiella pneumoniae, comparable to the reference antibiotic amikacin, with a minimum inhibitory concentration (MIC) of 8 μg·mL^(−1).

关键词： Arthrinium sp.ZS03 Pimarane diterpenoids Structural elucidation Antibacterial activity

A new gravitational theory and dark matter problem

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Communications in Theoretical Physics 2024年第6期76卷 129-136页

作者： Xiong zhao Yongge Ma Department of Physics Beijing Normal UniversityBeijing 100875China

We propose a new gravitational theory with torsion based on Riemann-Cartan geometry,in which all physical quantities are *** addition to the spacetime metric,the gravitational degrees of freedom in this theory also include the torsion and two scalar *** energy-momentum tensor of the matter fields in this theory is also proposed.A spherically symmetric static vacuum solution of the theory is *** turns out that this solution can fit the observational data of the rotation curve outside the stellar disk in the Milky ***,the galactic dark matter may just be the gravitational effect of the theory with torsion.

关键词： gravity torsion dark matter

Universal method for designing periodic orbits by homotopy classes in the elliptic restricted three-body problem

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Astrodynamics 2024年第1期8卷 175-188页

作者： Yue Zheng Min zhao School of Electronic Engineering Xi’an Aeronautical InstituteXi’an710077China School of Aircraft Engineering Xi’an Aeronautical InstituteXi’an710077China School of Astronautics Northwestern Polytechnical UniversityXi’an710072China

The current methods for designing periodic orbits in the elliptic restricted three-body problem(ERTBP)have the disadvantages of targeting limited orbits and ergodic searches and considering only symmetric orbits.A universal method for designing periodic orbits is proposed in this ***,the homotopy classes of orbits are structured based on their topological ***,a dynamic model based on homotopy classes,ranging from the circular restricted three-body problem(CRTBP)to the ERTBP,can be built using the homotopy ***,a multi-and a single-period orbit were selected based on the resonance ***,the corresponding orbit in the ERTBP was computed by modifying the initial condition of the orbit in the *** method,without an ergodic search,can extend to any orbit,including an asymmetric orbit in the CRTBP,to the ERTBP model,and the two orbits are of the same homotopy *** of the Earth–Moon ERTBP are presented to verify the efficiency of this method.

关键词： periodic orbit elliptic restricted three-body problem(ERTBP) topology homotopy circular restricted three-body problem(CRTBP)

Citrin缺陷所致婴儿肝内胆汁淤积症的肝胆显像特征

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中华核医学与分子影像杂志 2014年第5期34卷 358-361页

作者：张梅虹赵瑞芳陈瑞王建设复旦大学附属金山医院儿科上海201508 复旦大学附属儿科医院核医学科复旦大学附属儿科医院肝病中心

目的探讨citrin缺陷导致的婴儿肝内胆汁淤积症（NICCD）患儿^99Tc^m-二乙基乙酰苯胺亚氨二醋酸（EHIDA）肝胆显像的特征.方法回顾性分析28例（男16例,女12例,1～8月龄）经基因确诊、同时行^99Tc^m-EHIDA肝胆动态显像检查的NICCD患儿资... 详细信息

目的探讨citrin缺陷导致的婴儿肝内胆汁淤积症（NICCD）患儿^99Tc^m-二乙基乙酰苯胺亚氨二醋酸（EHIDA）肝胆显像的特征.方法回顾性分析28例（男16例,女12例,1～8月龄）经基因确诊、同时行^99Tc^m-EHIDA肝胆动态显像检查的NICCD患儿资料.肝胆动态显像时心、肝、肾按正常时序和强度显影定义为摄取功能正常,肝影模糊和（或）心肾影持续时间延长者为摄取功能差;60 min内肠道显影为排泄通畅,60 min后为排泄延迟,24 h肠道仍不显影为排泄受阻.分析肝胆显像特征与血清总胆红素（TB）、直接胆红素（DB）、ALT、总胆汁酸（TBA）等指标间的关系.数据分析采用Kruskal-Wallis秩和检验.结果 28例中,20例表现为摄取功能正常,其中10例排泄通畅,10例排泄延迟;8例表现为摄取功能差,其中4例排泄延迟,4例排泄受阻.与摄取功能正常组相比,摄取功能差组TB和DB明显增高[183.6（128.7～ 280.9） mmol/L和105.5（80.0～ 141.7） mmol/L,135.6（95.7～212.6） mmol/L和73.1（53.9～ 97.9） mmol/L;Z=-2.25和-2.73,均P＜0.05].与排泄通畅者相比,排泄延迟者TB、DB和TBA明显升高[分别为137.5（122.0～170.9） mmol/L和81.7（65.7～93.5） mmol/L,96.5（81.1～ 108.0） mmol/L和54.1（45.3～72.6） mmol/L,245.6（183.9～299.2） mmol/L和136.0（73.5 ～163.2） mmol/L;Z=-3.92、-3.74和-2.57,均P＜0.05];排泄受阻者TB[262.0（152.1 ～ 542.8） mmol/L]和DB[192.7（118.1～407.2） mmol/L]更高（均Z=-2.82,均P＜0.05）.与排泄延迟组相比,排泄受阻者ALT明显增高[71.5（48.5～144.8） U/L和20.0（16.5～27.7） U/L;Z=-2.66,P＜0.05）.结论 ^99Tc^m-EHIDA肝胆显像可反映NICCD患儿肝脏摄取和排泄功能受损的状况,摄取功能受损严重时,可出现排泄受阻的征象.

关键词：胆汁郁积,肝内婴儿,新生放射性核素显像 EHIDA

New lump solutions and several interaction solutions and their dynamics of a generalized(3+1)-dimensional nonlinear differential equation

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Communications in Theoretical Physics 2024年第2期76卷 1-13页

作者： Yexuan Feng Zhonglong zhao School of Mathematics North University of ChinaTaiyuanShanxi 030051China

In this paper,we mainly focus on proving the existence of lump solutions to a generalized(3+1)-dimensional nonlinear differential ***’s bilinear method and a quadratic function method are employed to derive the lump solutions localized in the whole plane for a(3+1)-dimensional nonlinear differential *** examples of such a nonlinear equation are presented to investigate the exact expressions of the lump ***,the 3d plots and corresponding density plots of the solutions are given to show the space structures of the lump *** addition,the breath-wave solutions and several interaction solutions of the(3+1)-dimensional nonlinear differential equation are obtained and their dynamics are analyzed.

关键词： lump solutions generalized(3+1)-dimensional nonlinear differential equation Hirota's bilinear method quadratic function method interaction solutions