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High-Efficiency Dynamic Terahertz Deflector Utilizing a Mechanically Tunable Metasurface

Research 2024年第3期2023卷 585-594页

作者： zhenci Sun Chao liang Chen Chen Xiayu Wang Enze zhou Xiaomeng Bian Yuanmu Yang Rui You Xiaoguang zhao jiahao zhao zheng You Department of Precision Instrument Tsinghua UniversityBeijing 100084China State Key Laboratory of Precision Measurement Technology and Instruments Tsinghua UniversityBeijing 100084China Beijing Advanced Innovation Center for Integrated Circuits Beijing 100084China School of Instrument Science and Opto-Electronic Engineering Beijing Information Science and Technology UniversityBeijing 100016China.

Terahertz (THz) wave manipulation, especially the beam deflection, plays an essential role in various applications, such as next-generation communication, space exploration, and high-resolution imaging. Current THz optical components and devices are hampered by their large bulk sizes and passive responses, limiting the development of high-performance, miniaturized THz microsystems. Tunable metasurfaces offer a powerful dynamic optical platform for controlling the propagation of electromagnetic waves. In this article, we presented a mechanically tunable metasurface (MTM), which can achieve terahertz beam deflection and vary the intensity of the anomalous reflected terahertz wave by changing the air gap between the metallic resonator (MR) array with phase discontinuities and Au ground plane. The absence of lossy spacer materials substantially enhances deflection efficiency. The device was fabricated by a combination of the surface and bulk-micromachining processes. The THz beam steering capability was characterized using terahertz time domain spectroscopy. When the air gap is 50 μm, the maximum deflection coefficient reaches 0.60 at 0.61 THz with a deflection angle of ~44.5°, consistent with theoretical predictions. We further established an electrically tunable miniaturized THz device for dynamic beam steering by introducing a micro voice coil motor to control the air gap continuously. It is shown that our designed MTM demonstrates a high modulation depth of deflection coefficient (~ 62.5%) in the target steered angle at the operating frequency. Our results showcase the potential of the proposed MTM as a platform for high-efficiency THz beam manipulation.

关键词： tunable Efficiency resonator

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New phenylbutenoids and terpene glycosides from Ginkgo biloba leaves

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Chinese journal of Natural Medicines 2024年第2期22卷 161-170页

作者： SUN zeshi LIN Shan WU zhi-Li DONG Hong-Yuan XU Xi-Ke LI Hui-liang WANG jinxin School of Pharmacy Second Military Medical UniversityShanghai 200433China State Key Laboratory of New Drug and Pharmaceutical Process Shanghai Institute of Pharmaceutical IndustryChina State Institute of Pharmaceutical IndustryShanghai 201203China

Our continued works on the chemical constituents of Ginkgo biloba(***)leaves has led to the isolation of two novel phenylbutenoids(1,2),along with five previously unidentified terpene glycosides(3−7).Among them,compounds 1 and 2 represent unique(z)-phenylbutenoids,3−6 are megastigmane glycosides,and 7 is identified as a rare bilobanone glycoside(Fig.1).This study marks the first reported isolation of phenylbutenoid and bilobanone glycoside from *** chemical structures of these compounds were elucidated through extensive spectroscopic analysis,including HR-ESI-MS and various 1D and 2D NMR ***,the absolute configurations of these molecules were determined using Mosher’s method,ECD experiments,and Cu-KαX-ray crystallographic analyses.

关键词： Ginkgo biloba Phenylbutenoid Megastigmane glycoside Bilobanone glycoside

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Microgels for Cell Delivery in Tissue Engineering and Regenerative Medicine

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Nano-Micro Letters 2024年第10期16卷 576-617页

作者： Leyan Xuan Yingying Hou Lu liang jialin Wu Kai Fan Liming Lian jianhua Qiu Yingling Miao Hossein Ravanbakhsh Mingen Xu Guosheng Tang Guangzhou Municipal and Guangdong Provincial Key Laboratory of Molecular Target and Clinical Pharmacology the NMPA and State Key Laboratory of Respiratory DiseaseSchool of Pharmaceutical Sciences and the Fifth Affiliated HospitalGuangzhou Medical UniversityGuangzhou 511436People's Republic of China School of Automation Hangzhou Dianzi UniversityHangzhou 310018People's Republic of China Department of Biomedical Engineering The University of AkronAkronOH 44325USA Wallace H.Coulter Department of Biomedical Engineering Georgia Institute of TechnologyAtlantaGA 30332USA

Microgels prepared from natural or synthetic hydrogel materials have aroused extensive attention as multifunctional cells or drug carriers,that are promising for tissue engineering and regenerative *** can also be aggregated into microporous scaffolds,promoting cell infiltration and proliferation for tissue *** review gives an overview of recent developments in the fabrication techniques and applications of microgels.A series of conventional and novel strategies including emulsification,microfluidic,lithography,electrospray,centrifugation,gas-shearing,three-dimensional bioprinting,*** discussed in *** characteristics and applications of microgels and microgel-based scaffolds for cell culture and delivery are elaborated with an emphasis on the advantages of these carriers in cell ***,we expound on the ongoing and foreseeable applications and current limitations of microgels and their aggregate in the field of biomedical *** stimulating innovative ideas,the present review paves new avenues for expanding the application of microgels in cell delivery techniques.

关键词： Microgels Cell delivery Scaffolds 3D bioprinting Single-cell microgels

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CONSTITUTIVE RELATIONSHIP OF IN718 ALLOY FOR THERMOVISCOPLASTIC AND MICROSTRUCTURE EVOLUTION COUPLED ANALYSIS

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Acta Metallurgica Sinica(English Letters) 2007年第5期20卷 373-379页

作者： D. Liu Y.H. Yang j. Geng z.j. Luo School of Materials Science Northwestern Polytechnical University Xi＇an 710072 China

The interaction between thermomechanical parameters and microstructure evolution is so intense that it must be considered during the finite element method （FEM） simulation of the hot plastic working process, for materials that are difficult to deform. Taking the microstructure evolution into account, a novel type of constitutive relationship has been put forward for the IN718 alloy. The microstructure evolution model was first established for the dominant microstructure evolution processes. Then the microstructure evolution models and the method to determine the local flow stress of the corresponding microstructure for current thermomechanical parameters and deformation history were presented. Once the local flow stresses of different structures and their volume contributions were defined, the apparent flow stress of the material could be determined as the weighted sum of the local flow stresses and volume contributions. To validate the proposed method, a thermoviscoplastics and microstructure evolution coupled analysis for a forging process of a critical IN718 disk forging was performed. The predicting results were in close agreement with the experimental data.

关键词： constitutive relationship microstructure evolution numerical simulation IN718 alloy

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OsPHR2-mediated recruitment of Pseudomonadaceae enhances rice phosphorus uptake

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Plant Communications 2024年第8期5卷 137-146页

作者： jianping Liu Weifeng Xu Qian zhang Wencheng Liao liang Li Shu Chen jinyong Yang zhengrui Wang Feiyun Xu Center for Plant Water-use and Nutrition Regulation and College of junCao Science and Ecology Joint International Research Laboratory of Water and Nutrient in CropFujian Agriculture and Forestry UniversityFuzhou 350002China

Plants can shape their root microbiome to promote growth and nutrient *** STARVATION RESPONSE 2(OsPHR2)is a central regulator of phosphate signaling in rice,but whether OsPHR2 can shape the root microbiome to promote phosphorus uptake is ***,we investigate the role of OsPHR2 in recruiting microbiota for phosphorus uptake using high-throughput sequencing and metabolite ***2-overexpressing(OsPHR2 OE)rice showed 69.8%greater shoot P uptake in natural soil compared with sterilized soil under high-phosphorus(HP)conditions,but there was only a 54.8%increase in the wildtype(WT).The abundance of the family Pseudomonadaceae was significantly enriched in OsPHR2 OE roots relative to those of WT *** with the WT,OsPHR2 OE rice had a relatively higher abundance of succinic acid and methylmalonic acid,which could stimulate the growth of Pseudomonas sp.(P6).After inoculation with P6,phosphorus uptake in WT and OsPHR2 OE rice was higher than that in uninoculated rice under low-phosphorus(LP)*** together,our results suggest that OsPHR2 can increase phosphorus use in rice through root exudate-mediated recruitment of *** finding reveals a cooperative contribution of the OsPHR2-modulated root microbiome,which is important for improving phosphorus use in agriculture.

关键词： OsPHR2 rice organic acid phosphorus Pseudomonadaceae

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Structure design of lead-free chiral-polar perovskites for sensitive self-powered X-ray detection

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Chinese journal of Structural Chemistry 2024年第6期43卷 34-39页

作者： Xin Dong Tianqi Chen jing liang Lei Wang Huajie Wu zhijin Xu junhua Luo Li-Na Li State Key Laboratory of Structural Chemistry Fujian Institute of Research on the Structure of MatterChinese Academy of SciencesFuzhou350002China Fujian Science&Technology Innovation Laboratory for Optoelectronic Information of China Fuzhou350108China University of the Chinese Academy of Sciences Beijing100039China

Metal halide perovskites have made significant progress in X-ray detection owing to their exceptional optoelec-tronic ***,most of these materials suffer from toxic element lead and require for high operating ***,it is imperative to explore environmentally friendly perovskite crystals without external bias for X-ray ***,we strategically introduce chiral cations to synthesize a pair of lead-free chiral-polar hybrid perovskites(S-MPz)_(6)Bi_(3)I_(21)·6H_(2)O and(R-MPz)_(6)Bi_(3)I_(21)·6H_(2)O(1S and 1R,S/R-MPz=S/R-2-methylpipera-zinium),which exhibit strong circular dichroism(CD)signals with an anisotropic g-factor reaching approximately ***,the chiral-polar feature gives rise to distinctive spontaneous polarization,which leads to a photovoltage of 1.1 V under X-ray illumination,endowing self-powered detection capabilities for *** exploration of X-ray devices based on 1R single crystal(SC)demonstrates a high sensitivity of 5.2 pC Gy_(air)^(-1)cm^(-2)at zero *** study realizes passive X-ray detection depending on the intrinsic spontaneous polarization induced built-in electric field of chiral-polar perovskite,providing an effective approach to the chemical design of desired materials for high-performance"green"self-powered radiation detection.

关键词： Lead-free perovskite Self-powered Chiral-polar X-ray detection

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Low Surface Brightness Galaxies from BASS+MzLS with Machine Learning

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Research in Astronomy and Astrophysics 2024年第5期24卷 185-197页

作者： Peng-liang Du Wei Du Bing-Qing zhang zhen-Ping Yi Min He Hong Wu Key Laboratory of Optical Astronomy National Astronomical ObservatoriesChinese Academy of SciencesBeijing 100101China School of Astronomy and Space Science University of Chinese Academy of SciencesBeijing 100049China School of Mechanical Electrical and Information EngineeringShandong UniversityWeihai 264209China

From ∼5000 deg^(2) of the combination of the Beijing–Arizona Sky Survey and Mayall z-band Legacy Survey which is also the northern sky region of the Dark Energy Spectroscopic Instrument (DESI) Legacy Imaging Surveys, we selected a sample of 31,825 candidates of low surface brightness galaxies (LSBGs) with the mean effective surface brightness 24.2 0.60) LSBGs. The blue LSBGs appear spiral, disk or irregular while the red LSBGs are spheroidal or elliptical and spatially clustered. This trend shows that the color has a strong correlation with galaxy morphology for LSBGs. In the spatial distribution, the blue LSBGs are more uniformly distributed while the red ones are highly clustered, indicating that red LSBGs preferentially populate a denser environment than the blue LSBGs. Besides, both populations have a consistent distribution of ellipticity (median ∈∼ 0.3), half-light radius (median r_(eff) ∼ 4″) and Sérsic index (median n=1), implying the dominance of the full sample by the round and disk galaxies. This sample has definitely extended the studies of LSBGs to a regime of lower surface brightness, fainter magnitude and broader other properties than the previously Sloan Digital Sky Survey-based samples.

关键词： catalogs-galaxies fundamental parameters-galaxies statistics-techniques photometric

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Recent development of three-dimension printed graphene oxide and MXene-based energy storage devices

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Tungsten 2024年第1期6卷 196-211页

作者： liang-Hao Yu Xin Tao Shang-Ru Feng jin-Tao Liu Lin-Lin zhang Guang-zhen zhao Guang zhu Key Laboratory of Spin Electron and Nanomaterials of Anhui Higher Education Institutes Suzhou UniversitySuzhou 234000China Key Laboratory of Leather of zhejiang Province College of Chemistry and Materials EngineeringWenzhou UniversityWenzhou 325035China

The research for three-dimension(3D)printing carbon and carbide energy storage devices has attracted widespread exploration *** designable in structure and materials,graphene oxide(GO)and MXene accompanied with a direct ink writing exhibit a promising prospect for constructing high areal and volume energy density *** review not only summarizes the recent advances in 3D printing energy storage devices including printing methods,ink rheological properties,and different energy storage systems,but also discusses the printing methods related to energy *** addition,the binder or additive free of two-dimensional carbide materials is quite important for the present electrochemical energy storage devices,which also are presented.

关键词： 3D printing Two-dimensional materials Energy storage device Ink theological MXene

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A Plasma Membrane Polarity Sensor Harnessing Conjoined Twisted Intramolecular Charge Transfer Modulation and Charge Number Control Strategy

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CCS Chemistry 2024年第3期6卷 733-748页

作者： Yu-Qiang zhao Le Yu Liping zhu jinsong liang Ying zhou jong Seung Kim College of Chemical Science and Technology Yunnan UniversityKunming 650091 Department of Chemistry Korea UniversitySeoul 02841 TheranoChem Incorporation Seoul 02856

Polarity is a critical microenvironmental factor of the plasma membrane,which can offer valuable insights into various biological ***,we proposed a novel strategy for the construction of fluorescent agents to measure plasma membrane polarity by conjoining twisted intramolecular charge transfer(TICT)modulation and charge number *** is shown that compounds with a stronger TICT tendency are more sensitive to polarity shifts due to the number of dialkylated amino groups present(from 1 to 3),and the molecules with two or more charged centers remain in the plasma ***,we developed two fluorescent agents with high polarity sensitivity,excellent turn-on ratios,and superior ability,to target the plasma *** the wash-free fluorescence imaging and fluorescence lifetime tests,our designed agent could detect plasma membrane polarity with high precision,allowing effective distinction between cancer cells and normal cells based on their differences in plasma membrane ***,both fluorescence and fluorescence lifetime changes of the plasma membrane in the ferroptosis model established by Sorafenib confirmed an increase in plasma membrane polarity during cell ferroptosis.

关键词： membrane polarity fluorescence agents fluorescence imaging fluorescence lifetime imaging

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MECHANISM AND KINETICS OF TRANSFORMATION OF ALUMINA INCLUSIONS BY CALCIUM TREATMENT

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Acta Metallurgica Sinica(English Letters) 2006年第1期19卷 1-8页

作者： z.j. Han L. Liu M. Lind L. Holappa Central Iron and Steel Research Institute Beijing 100081 China Laboratory of Metallurgy Helsinki University of Technology P.O. Box 6200Espoo 02015 Finland

The basic mechanism and kinetics of the transformation process of alumina inclusions in steel was reported when calcium introduced into the steel by wire feeding orpowder injection. To clarify the mechanisms model, experiments were performed by studying reactions between AltOs and CaO in a laboratory furnace and by performing calcium treatments in an 8kg induction furnace for Al deoxidised melt. The phases formed during the reaction between Al2O3 and CaO were examined by SEM-EDS （scanning electron microscope-energy dispersive spectrometer）, and the reaction sequence of Al2O3=〉 CA6=〉 CA2 =〉 CA =〉 CAx（l） was discussed in term of the experimental observations. The kinetics of the reaction of calcium with alumina inclusions were simulated by immersing alumina plates in a Ca treated steel melt in the induction furnace. Results were compared with observations of real inclusion transformation. A kinetic model was proposed based on the results.

关键词： mechanism kinetics alumina inclusion transformation

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