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A 3D-printed microhemispherical shell resonator with electrostatic tuning for a Coriolis vibratory gyroscope

Microsystems & Nanoengineering 2024年第2期10卷 25-35页

作者： Baoyin Hou Ye Zhu Chaofan he Weidong Wang Zhi Ding wen he Yong he Lufeng Che College of Information Science and Electronic Engineering Zhejiang UniversityHangzhou310027China Center for Microelectronics Shaoxing InstituteZhejiang UniversityShaoxing312035China State Key Laboratory of Fluid Power and Mechatronic Systems Zhejiang UniversityHangzhou310058China School of Mechanical Engineering Zhejiang UniversityHangzhou310058China

The emergence of microhemispherical resonant gyroscopes,which integrate the advantages of exceptional stability and long lifetime with miniaturization,has afforded new possibilities for the development of whole-angle gyroscopes.However,existing methods used for manufacturing microhemispherical resonant gyroscopes based on MEMS technology face the primary drawback of intricate and costly processing.here,we report the design,fabrication,and characterization of the first 3D-printable microhemispherical shell resonator for a Coriolis vibrating gyroscope.We remarkably achieve fabrication in just two steps bypassing the dozen or so steps required in traditional micromachining.By utilizing the intricate shaping capability and ultrahigh precision offered by projection microstereolithography,we fabricate 3D high-aspect-ratio resonant structures and controllable capacitive air gaps,both of which are extremely difficult to obtain via MEMS technology.In addition,the resonance frequency of the fabricated resonators can be tuned by electrostatic forces,and the fabricated resonators exhibit a higher quality factor in air than do typical MEMS microhemispherical resonators.This work demonstrates the feasibility of rapidly batch-manufacturing microhemispherical shell resonators,paving the way for the development of microhemispherical resonator gyroscopes for portable inertial navigation.Moreover,this particular design concept could be further applied to increase uptake of resonator tools in the MEMS community.

关键词： resonator tuning electrostatic

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Low profile cavity-embedded ultra-wideband UHF array antenna with end-fire beams

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Journal of Electronic Science and Technology 2024年第2期22卷 24-35页

作者： Huan he wen-Song Wang Southwest China Institute of Electronic Technology Chengdu610036China School of Electrical and Electronic Engineering Department Nanyang Technological UniversitySingapore639798Singapore

A low-profile,vertically polarized,ultra-wideband array antenna with end-fire beams operating in an ultra-high frequency(UHF)band is developed in this paper.The array antenna consists of 1×16 log-periodic top-hat loaded monopole antenna arrays and is feasible to embed into a shallow cavity to further reduce the array height.Capacitance is introduced in the proposed antenna element to reduce profile height and the rectangular top hats are carefully designed to minimize the transverse dimension.Simulated results show that when the antenna array operates in a frequency range of 300 MHz-900 MHz,the end-fire radiation pattern achieves±45°scanning range in the horizontal plane.Then prototypes of the proposed end-fire antenna element and a uniformly spaced linear array(1×2)are fabricated and validated.The end-fire antenna array should be suitable for airborne applications where low-profile and conformal scanning phased antenna arrays with end-fire radiations are required.This design is attractive for airborne platform applications that are used to search,discover,identify,and scout the aerial target with vertically polarized beams.

关键词： End-fire radiation Low-profile Vertical polarization Log-periodic array

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Interaction of yttrium barrier and calcium-rich phase on production and properties of WC precursor powders and alloys

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Journal of Rare Earths 2024年第1期42卷 228-236,I0008页

作者： wen he Dunqiang Tan Zhiqiang Yi Zhiqiang Liu School of Materials Science and Engineering Nanchang UniversityNanchang330031China Instrumental Analysis Center of Nanchang Hangkong University Nanchang330063China

In order to reduce or eliminate the adverse effects of calcium impurity,the interaction of Ca and rare earth Y co-doping on the preparation of WC-Co cemented carbides was investigated.X-ray diffraction,scanning electron microscopy and transmission electron microscopy were employed to analyze the phase compositions,particle sizes and morphologies of them,respectively.The results show that the second type of"yttrium barrier effect"is observed and the adverse influence of Ca-rich phase on tungsten powder can be eliminated by it.The flexural strength and fracture toughness of YG6-0.01%Ca+0.09%Y alloy are 2199.5 MPa and 11.49 MPa·m^(1/2),showing improvement of 6.5% and 2.7% compared to YG6 alloy,respectively.The evolutions of Ca-rich phase and Y-rich phase at the every alloy preparation stage of WO_(3),W,WC and cemented carbides are obtained.Furthermore,the strengthening mechanism of WC-Co cemented carbide with co-addition of Ca and Y is proposed.

关键词： Yttrium barrier effect Ca-rich phase WC-Co cemented Carbide Microstructures Mechanisms Rare earths

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pH Induced Self-assembly of AIE Fluorescent Probe for Tumor Imaging

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Chinese Journal of Polymer Science 2024年第1期42卷 7-13,I0005页

作者： Jing-Yuan Xiang wen-Long Zhang he-Ting Li Ya-Ning he Department of Chemical Engineering Key Laboratory of Advanced Materials(MOE)Tsinghua UniversityBejing 100084China

This work reported an AIE fluorescent probe for tumor imaging based on the p H induced self-assembly strategy. The fluorescent probe was composed of an acid-responsive soluble copolymer PEG-b-PAMA-DMMA with a maleic acid amide group and an anionic soluble aggregation-induced emission fluorogen(AIEgen) TPE-2SO_(3)^(-). The polymer could be transformed into a protonated amine-containing polymer after the hydrolysis of maleic acid amide in acidic tumor microenvironment, which would be further self-assembled with TPE-2SO_(3)^(-)to form aggregated nanoparticles. The transition of TPE-2SO_(3)^(-)from dispersed state to aggregated state led to an obvious increase in fluorescence intensity due to its AIE characteristics.

关键词： p H-responsive Self-assembly Fluorescent probe AIE Tumor imaging

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Palladium Complexes with N,O-Bidentate Ligands Based on N-Oxide Units from Cyclic Secondary Amines:Synthesis and Catalytic Application in Mizoroki-heck Reaction

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Chinese Journal of Chemistry 2024年第3期42卷 294-300页

作者： Xuefeng Jia Yanyan wen Changhui he Xianqiang Huang Key Laboratory of Magnetic Molecules and Magnetic Information Materials of Ministry of Education School of Chemistry and Materials ScienceShanxi Normal UniversityTaiyuanShanxi030032 China Shandong Provincial Key Laboratory of Chemical Energy Storage and Novel Cell Technology School of Chemistry & Chemical EngineeringLiaocheng UniversityLiaochengShandong252059 China

Palladium-catalyzed Mizoroki-heck reaction is a powerful and efficient method for construction of Csp2–Csp2 bonds.herein,four palladium complexes(I—IV)with N,O-bidentate ligands(L1—L4)based on N-oxide units from cyclic secondary amines were easily synthesized and successfully applied in Mizoroki-heck reaction of aryl bromides with electron-deficient olefins.X-ray diffraction analyses indicated the palladium(II)atom of II took the distorted square planar geometry and was four-coordinated by nitrogen and oxygen atoms from two ligands(L2).Two free chloride ions were presented as counter anions in complex II.But the palladium(II)center of IV was coordinated by nitrogen and oxygen atoms from one ligand(L4)as well as two chlorine atoms,which exhibited the nearly square-planar geometry.The study on catalytic properties of palladium complexes revealed that complex II exhibited high activity superior to the other complexes.The coupling reactions of a series of aryl bromides and olefin derivatives proceeded in the presence of 2—5 mol%palladium complex II,giving the desired products in good to excellent yields.The advantages of this method such as good compatibility of functional groups,high yields,and short reaction times made it more attractive for constructing Csp2–Csp2 bonds in the synthesis of functional molecules and materials.

关键词： Palladium complexes N,O-Bidentate ligands N-Oxide units Mizoroki-heck reaction Aryl bromide Electron-deficient olefins C—C coupling Homogeneous catalysis Substituent effects

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Asymmetric Drying and Wetting Trends in Eastern and Western China

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Advances in Atmospheric Sciences 2024年第2期41卷 221-232页

作者： wen WU Fei JI Shujuan HU Yongli he College of Atmospheric Sciences Lanzhou UniversityLanzhou 730000China Collaborative Innovation Center for Western Ecological Safety Lanzhou UniversityLanzhou 730000China

As an important factor that directly affects agricultural production, the social economy, and policy implementation,observed changes in dry/wet conditions have become a matter of widespread concern. However, previous research has mainly focused on the long-term linear changes of dry/wet conditions, while the detection and evolution of the non-linear trends related to dry/wet changes have received less attention. The non-linear trends of the annual aridity index, obtained by the Ensemble Empirical Mode Decomposition(EEMD) method, reveal that changes in dry/wet conditions in China are asymmetric and can be characterized by contrasting features in both time and space in China. Spatially, most areas in western China have experienced transitions from drying to wetting, while opposite changes have occurred in most areas of eastern China. Temporally, the transitions occurred earlier in western China compared to eastern China. Research into the asymmetric spatial characteristics of dry/wet conditions compensates for the inadequacies of previous studies, which focused solely on temporal evolution;at the same time, it remedies the inadequacies of traditional research on linear trends over centennial timescales. Analyzing the non-linear trend also provides for a more comprehensive understanding of the drying/wetting changes in China.

关键词： aridity index EEMD dry/wet conditions asymmetric evolution

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N-glycan biosignatures as a potential diagnostic biomarker for earlystage pancreatic cancer

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World Journal of Gastrointestinal Oncology 2024年第3期16卷 659-669页

作者： Yan-Rong wen Xia-wen Lin Yu-wen Zhou Lei Xu Jun-Li Zhang Cui-Ying Chen Jian he Department of Nuclear Medicine Nanjing Drum Tower HospitalAffiliated Hospital of Medical SchoolNanjing UniversityNanjing 210008Jiangsu ProvinceChina Department of Research and Development Sysdiagno(Nanjing)Biotech Co.LtdNanjing 210008Jiangsu ProvinceChina

BACKGROUND Pancreatic ductal adenocarcinoma(PDAC)has a poor prognosis,with a 5-year survival rate of less than 10%,owing to its late-stage diagnosis.Early detection of pancreatic cancer(PC)can significantly increase survival rates.AIM To identify the serum biomarker signatures associated with early-stage PDAC by serum N-glycan analysis.METHODS An extensive patient cohort was used to determine a biomarker signature,in-cluding patients with PDAC that was well-defined at an early stage(stages I and II).The biomarker signature was derived from a case-control study using a case-cohort design consisting of 29 patients with stage I,22 with stage II,4 with stage III,16 with stage IV PDAC,and 88 controls.We used multiparametric analysis to identify early-stage PDAC N-glycan signatures and developed an N-glycan sig-nature-based diagnosis model called the“Glyco-model”.RESULTS The biomarker signature was created to discriminate samples derived from patients with PC from those of controls,with a receiver operating characteristic area under the curve of 0.86.In addition,the biomarker signature combined with cancer antigen 19-9 could discriminate patients with PDAC from controls,with a receiver operating characteristic area under the curve of 0.919.Glyco-model demonstrated favorable diagnostic performance in all stages of PC.The diagnostic sensitivity for stage I PDAC was 89.66%.Core Tip:This study employed a patient cohort to investigate the N-glycan signature of early-stage pancreatic cancer(PC).Serum N-glycans analysis was conducted to identify the serum biomarker signature associated with early-stage pancreatic ductal adenocarcinoma(PDAC),resulting in the identification of nine early-stage PDAC N-glycan signatures.Subsequently,utilizing these biosignatures,a diagnostic model named the“Glyco-model”was developed,demonstrating promising diagnostic performance across all stages of PC.The study revealed that the diagnostic sensitivity for stage I PDAC was determined to be 89.66%.Consequently,this diagnostic model exhibits potent

关键词： Glycomics N-glycans Biomarkers Pancreatic cancer Predictive modeling

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Geochemical identification of a source rock affected by migrated hydrocarbons and its geological significance:Fengcheng Formation,southern Mahu Sag,Junggar Basin,NW China

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Petroleum Science 2024年第1期21卷 100-114页

作者： wen-Long Dang Gang Gao Xin-Cai You Ke-Ting Fan Jun Wu De-wen Lei wen-Jun he Yong Tang State Key Laboratory of Petroleum Resource and Prospecting China University of Petroleum(Beijing)Beijing102249China School of GeoSciences China University of Petroleum(Beijing)Beijing102249China Exploration&Development Institute Xinjiang Oil Field CompanyKaramay834000XinjiangChina

The Fengcheng Formation is a crucial source rock and the primary reservoir for oil accumulation in the Mahu Sag.Crude oils are distributed throughout the Fengcheng Formation,ranging from the edge to the interior of the sag in the southern Mahu Sag.These crude oils originate from in-situ source rocks in shallowly buried areas and the inner deep sag.During migration,the crude oil from the inner deep sag affects the source rocks close to carrier beds,leading to changes in the organic geochemical characteristics of the source rocks.These changes might alter source rock evaluations and oil-source correlation.Based on data such as total organic carbon(TOC),Rock-Eval pyrolysis of source rocks,and gas chromatography-mass spectrometry(GC-MS)of the saturated fraction,and considering the geological characteristics of the study area,we define the identification characteristics of source rock affected by migrated hydrocarbons and establish the various patterns of influence that migrated hydrocarbons have on the source rock of the Fengcheng Formation in the southern Mahu Sag.The source rocks of the Fengcheng Formation are mostly fair to good,containing mainly Type II organic matter and being thermally mature enough to generate oil.Source rocks affected by migrated hydrocarbons exhibit relatively high hydrocarbon contents(S1/TOC>110 mg HC/g TOC,Extract/TOC>30%,HC:hydrocarbon),relatively low Rock-Eval Tmax values,and relatively high tricyclic terpane contents with a descending and mountain-shaped distribution.Furthermore,biomarker composition parameters indicate a higher thermal maturity than in-situ source rocks.Through a comparison of the extract biomarker fingerprints of adjacent reservoirs and mudstones in different boreholes,three types of influence patterns of migrated hydrocarbons are identified:the edge-influence of thin sandstone-thick mudstone,the mixed-influence of sandstone-mudstone interbedded,and the full-influence of thick sandstone-thin mudstone.This finding reminds us that the influence of migrated hydrocarbons

关键词： Organic geochemistry Source rock Influence of migrated hydrocarbons Fengcheng Formation Southern Mahu Sag

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Low-rank matrix recovery with total generalized variation for defending adversarial examples

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Frontiers of Information Technology & Electronic Engineering 2024年第3期25卷 432-445页

作者： wen LI hengyou WANG Lianzhi HUO Qiang he Linlin CheN Zhiquan he Wing W.Y.Ng School of Science Beijing University of Civil Engineering and ArchitectureBeijing 100044China School of Computer Science and Engineering South China University of TechnologyGuangzhou 510006China Aerospace Information Research Institute Chinese Academy of SciencesBeijing 100094China Guangdong Key Laboratory of Intelligent Information Processing Shenzhen 518060China Institute of Big Data Modeling and Technology Beijing University of Civil Engineering and ArchitectureBeijing 100044China

Low-rank matrix decomposition with first-order total variation(TV)regularization exhibits excellent performance in exploration of image structure.Taking advantage of its excellent performance in image denoising,we apply it to improve the robustness of deep neural networks.However,although TV regularization can improve the robustness of the model,it reduces the accuracy of normal samples due to its over-smoothing.In our work,we develop a new low-rank matrix recovery model,called LRTGV,which incorporates total generalized variation(TGV)regularization into the reweighted low-rank matrix recovery model.In the proposed model,TGV is used to better reconstruct texture information without over-smoothing.The reweighted nuclear norm and Li-norm can enhance the global structure information.Thus,the proposed LRTGV can destroy the structure of adversarial noise while re-enhancing the global structure and local texture of the image.To solve the challenging optimal model issue,we propose an algorithm based on the alternating direction method of multipliers.Experimental results show that the proposed algorithm has a certain defense capability against black-box attacks,and outperforms state-of-the-art low-rank matrix recovery methods in image restoration.

关键词： Total generalized variation Low-rank matrix Alternating direction method of multipliers Adversarial example

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Visualization analysis of research hotspots and trends on gastrointestinal tumor organoids

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World Journal of Gastrointestinal Oncology 2024年第6期16卷 2826-2841页

作者： Gang Wang Tao Liu wen-Ting he School of Basic Medical Sciences Lanzhou UniversityLanzhou 730000Gansu ProvinceChina Digestive System Tumor Prevention and Treatment and Translational Medicine Engineering Innovation Center of Lanzhou University Lanzhou UniversityLanzhou 730000Gansu ProvinceChina Digestive System Tumor Translational Medicine Engineering Research Center of Gansu Province Lanzhou UniversityLanzhou 730000Gansu ProvinceChina The Second Hospital&Clinical Medical School Lanzhou UniversityLanzhou 730030Gansu ProvinceChina

BACKGROUND Gastrointestinal tumor organoids serve as an effective model for simulating cancer in vitro and have been applied in basic biology and preclinical research.Despite over a decade of development and increasing research achievements in this field,a systematic and comprehensive analysis of the research hotspots and future trends is lacking.AIM To address this problem by employing bibliometric tools to explore the publication years,countries/regions,institutions,journals,authors,keywords,and references in this field.METHODS The literature was collected from Web of Science databases.CiteSpace-6.2R4,a widely used bibliometric analysis software package,was used for institutional analysis and reference burst analysis.VOSviewer 1.6.19 was used for journal cocitation analysis,author co-authorship and co-citation analysis.The‘online platform for bibliometric analysis(https://***/app)’was used to assess the total number of publications and the cooperation relationships between countries.Finally,we employed the bibliometric R software package(version R.4.3.1)in R-studio,for a comprehensive scientific analysis of the literature.RESULTS Our analysis included a total of 1466 publications,revealing a significant yearly increase in articles on the study of gastrointestinal tumor organoids.The United States(n=393)and helmholtz Association(n=93)have emerged as the leading countries and institutions,respectively,in this field,with Hans Clevers and Toshiro Sato being the most contributing authors.The most influential journal in this field is Gastroenterology.The most impactful reference is"Long term expansion of epithelial organs from human colon,adenoma,adenocarcinoma,and Barrett's epithelium".Keywords analysis and citation burst analysis indicate that precision medicine,disease modeling,drug development and screening,and regenerative medicine are the most cutting-edge directions.These focal points were further detailed based on the literature.CONCLUSION This bibliometric study offers an objective and quantitative analysis

关键词： Gastrointestinal tumor organoids Bibliometric analysis Drug development and screening Model CiteSpace

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