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Nano Research 2024年第4期17卷 3130-3138页

作者： Zedong Hu Juanjuan Lu Hongyi dou Jianan Shen James PBarnard Juncheng Liu Xinghang Zhang Haiyan Wang School of Electrical and Computer Engineering Purdue UniversityWest LafayetteIN 47906USA School of Materials Engineering Purdue UniversityWest LafayetteIN 47906USA

Oxide-metal based nanocomposite thin films have attracted great interests owing to their unique anisotropic structure and physical properties.A wide range of Au-based oxide-metal nanocomposites have been demonstrated,while other metal systems are scarce due to the challenges in the initial nucleation and growth as well as possible interdiffusions of the metallic nanopillars.In this work,a unique anodic aluminum oxide(AAO)template was used to grow a thin Co seed layer and the following self-assembled metal-oxide(Co-BaTiO_(3))vertically aligned nanocomposite thin film layer.The AAO template allows the uniform growth of Co-seeds and successfully deposition of highly ordered Co pillars(with diameterkerr effect(MOke)has also been observed which inspires a novel optical-based reading method of the MTJ states.

关键词： vertically aligned nanocomposite(VAN) Co BaTiO_(3) thin film magneto-optical coupling magnetic anisotropy

Improved LS+MAR hybrid method to UT1-UTC ultra-short-term prediction by using first-order-difference UT1-UTC

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Geodesy and Geodynamics 2024年第4期15卷 379-385页

作者： fei Ye Yunbin Yuan Bei dou High-precision Satellite Navigation and Location Service Hunan Engineering Research Center Hunan Institute of Geomatics Sciences and Technology State key Laboratory of Geodesy and Earth's Dynamics Innovation Academy for Precision Measurement Science and Technology Chinese Academy of Sciences HNCORS Data Center Hunan Institute of Geomatics Sciences and Technology

Accurate ultra-short-term prediction of the Earth rotation parameters(ERP) holds paramount importance for real-time applications, particularly in reference frame conversion. Among them, diurnal rotation(UT1-UTC) which cannot be directly estimated through Global Navigation Satellite System(GNSS)techniques, significantly affects the rapid and ultra-rapid orbit determination of GNSS satellites. Presently, the traditional LS(least squares) + AR(autoregressive) and LS + MAR(multivariate autoregressive)hybrid methods stand as primary approaches for UT1-UTC ultra-short-term predictions(1-10 days). The LS + MAR hybrid method relies on the UT1-UTC and LOD(length of day) series. However, the correlation between LOD and first-order-difference UT1-UTC is stronger than that between LOD and UT1-UTC. In light of this, and with the aid of the first-order-difference UT1-UTC, we propose an enhanced LS + MAR hybrid method to UT1-UTC ultra-short-term prediction. By using the UT1-UTC and LOD data series of the IERS(International Earth Rotation and Reference Systems Service) EOP 14 C04 product, we conducted a thorough analysis and evaluation of the improved method's prediction performance compared to the traditional LS + AR and LS + MAR hybrid methods. According to the numerical results over more than210 days, they demonstrate that, when considering the correlation information between the LOD and the first-order-difference UT1-UTC, the mean absolute errors(MAEs) of the improved LS + MAR hybrid method range from 21 to 934 μs in 1-10 days predictions. In comparison to the traditional LS + AR hybrid method, the MAEs show a reduction of 7-53 μs in 1-10 days predictions, with corresponding improvement percentages ranging from 1 to 28%. Similarly, when compared to the traditional LS + MAR hybrid method, the MAEs have a reduction of 5-42 μs in 1-10 days predictions, with corresponding improvement percentages ranging from 4-20%. Additionally, when aided by GNSS-derived LOD data series, the MAEs of improved LS + MAR hybrid method experience fu

关键词： UT1-UTC ultra-short-term prediction Rapid and ultra-rapid products LS+AR and LS+MAR Correlation First-order-difference UT1-UTC

Novel C_(sf)/SiBCN composites prepared by densifying Csf/MA-SiBCN with the PIP process:Oxidation behavior and damage mechanism

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Journal of Advanced Ceramics 2024年第5期13卷 666-678页

作者： Wenhao dou Daxin Li Bingzhu Wang Zhihua Yang Jun Chen Dechang Jia Ralf Riedel Yu Zhou Institute for Advanced Ceramics School of Materials Science and EngineeringHarbin Institute of TechnologyHarbin 150001China key Laboratory of Advanced Structural-Functional Integration Materials and Green Manufacturing Technology Harbin Institute of TechnologyHarbin 150001China Chongqing Research Institute of HIT Chongqing 401135China Beijing Institute of Control Engineering Beijing 100094China Institut für Materialwissenschaft Technische Universität DarmstadtDarmstadt D-64287Germany School of Materials Science and Engineering Harbin Institute of Technology(Shenzhen)Shenzhen 518055China

To improve the oxidation resistance of short carbon fiber(C_(sf))-reinforced mechanically alloyed SiBCN(MA-SiBCN)(C_(sf)/MA-SiBCN)composites,dense amorphous C_(sf)/SiBCN composites containing both MA-SiBCN and polymer-derived ceramics SiBCN(PDCs-SiBCN)were prepared by repeated polymer infiltration and pyrolysis(PIP)of layered C_(sf)/MA-SiBCN composites at 1100°C,and the oxidation behavior and damage mechanism of the as-prepared C_(sf)/SiBCN at 1300–1600°C were compared and discussed with those of C_(sf)/MA-SiBCN.The C_(sf)/MA-SiBCN composites resist oxidation attack up to 1400°C but fail at 1500°C due to the collapse of the porous framework,while the PIP-densified C_(sf)/SiBCN composites are resistant to static air up to 1600°C.During oxidation,oxygen diffuses through preexisting pores and the pores left by oxidation of carbon fibers and pyrolytic carbon(PyC)to the interior of the matrix.Owing to the oxidative coupling effect of the MA-SiBCN and PDCs-SiBCN matrices,a relatively continuous and dense oxide layer is formed on the sample surface,and the interfacial region between the oxide layer and the matrix of the as-prepared composite contains an amorphous glassy structure mainly consisting of Si and O and an incompletely oxidized but partially crystallized matrix,which is primarily responsible for improving the oxidation resistance.

关键词： mechanically alloyed SiBCN(MA-SiBCN) polymer-derived ceramics SiBCN(PDCs-SiBCN) short carbon fiber-reinforced SiBCN(C_(sf)/SiBCN)composites polymer infiltration and pyrolysis(PIP) oxidation damage mechanism

Co-aromatization of methane and hexane over Pt encapsulated in ZSM-5 zeolite and the electronic effect of K promoters

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Science China Chemistry 2024年第3期67卷 1017-1027页

作者： Bei Liu Fan Wang Xiaomeng dou Pengfei Li Hongwei Xiang Yong Yang Peng He State key Laboratory of Coal Conversion Institute of Coal ChemistryChinese Academy of SciencesTaiyuan 030001China Department of Chemistry Tsinghua UniversityBeijing 100084China National Energy R&D Center for Coal to Liquid Fuels Synfuels China Technology Co.Ltd.Beijing 101407China University of Chinese Academy of Sciences Beijing 101408China Leibniz-Institut für Katalyse e.V.an der Universitat Rostock Rostock 18059Germany

The co-aromatization of methane with higher hydrocarbons represents a promising route to valorize methane, an abundant but underexploited carbon resource. In this study, we elucidate a novel approach to enhance the catalytic co-aromatization of hexane and methane by confining Pt within zeolite catalysts and modulating its electron density. Our findings show that encapsulating Pt within MFI structure is pivotal for activating the feedstock and fostering the formation of aromatic products. Interaction between K atoms and the silanol nest forms siloxy groups which are critical for the stabilization of Pt species. Tuning the K content in PtSn@MFI catalysts adeptly alters the electronic configuration of Pt clusters. This modification is corroborated by infrared and X-ray photoelectron spectroscopy analysis, and density functional theory calculations. Remarkably, the catalyst with 0.8 wt% K exhibits an optimal Pt electron density, driving its superior efficacy in the co-aromatization reaction, converting 0.78 mol of methane for each mole of hexane processed. By employing ~(13)C isotopic labeling and solid-state NMR studies, we demonstrate the participation of methane in the adsorbed species inside the zeolite channel and its incorporation to the benzyl site of the substitute group and phenyl rings in aromatic compounds, underscoring the importance of Pt encapsulation.

关键词： Pt encapsulation MFI zeolite methane activation co-aromatization ^(13)C solid-state NMR

Nuciferine alleviates collagen-induced arthritic in rats by inhibiting the proliferation and invasion of human arthritis-derived fibroblast-like synoviocytes and rectifying Th17/Treg imbalance

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Chinese Journal of Natural Medicines 2024年第4期22卷 341-355页

作者： WANG Hao GENG Xiaolong AI Fangbin YU Zhilun ZHANG Yan ZHANG Beibei LV Cheng GAO Ruiyang YUE Bei dou Wei The MOE key Laboratory of Standardization of Chinese Medicines Shanghai Key Laboratory of Compound Chinese Medicinesand the SATCM Key Laboratory of New Resources and Quality Evaluation of Chinese MedicineInstitute of Chinese Materia MedicaSchool of Traditional Chinese Materia MedicaShanghai University of Traditional Chinese Medicine(SHUTCM)Shanghai 201203China

Rheumatoid arthritis(RA)is a chronic autoimmune disorder marked by persistent synovial inflammation and joint degradation,posing challenges in the development of effective treatments.Nuciferine,an alkaloid found in lotus leaf,has shown promising anti-inflammatory and anti-tumor effects,yet its efficacy in RA treatment remains unexplored.This study investigated the antiproliferative effects of nuciferine on the MH7A cell line,a human RA-derived fibroblast-like synoviocyte,revealing its ability to inhibit cell proliferation,promote apoptosis,induce apoptosis,and cause G1/S phase arrest.Additionally,nuciferine significantly reduced the migration and invasion capabilities of MH7A cells.The therapeutic potential of nuciferine was further evaluated in a collagen-induced arthritis(CIA)rat model,where it markedly alleviated joint swelling,synovial hyperplasia,cartilage injury,and inflammatory infiltration.Nuciferine also improved collagen-induced bone erosion,decreased pro-inflammatory cytokines and serum immunoglobulins(IgG,IgG1,IgG2a),and restored the balance between T helper(Th)17 and regulatory T cells in the spleen of CIA rats.These results indicate that nuciferine may offer therapeutic advantages for RA by decreasing the proliferation and invasiveness of FLS cells and correcting the Th17/Treg cell imbalance in CIA rats.

关键词： Rheumatoid arthritis Collagen-induced arthritis Fibroblast-like synoviocyte Immune imbalance Nuciferine

Oroxyloside protects against dextran sulfate sodium-induced colitis by inhibiting ER stress via PPARγ activation

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Chinese Journal of Natural Medicines 2024年第4期22卷 307-317页

作者： TAO Lei dou Renjie CHEN Xueming CAO Yu DAI Zhen HU Ziyan MA Zhi GE Xiaoming ZHANG Ling WANG Xiaoping Nanjing Institute for Food and Drug Control Nanjing 211198China State key Laboratory of Natural Medicines School of Basic Medicine and Clinical PharmacyChina Pharmaceutical UniversityNanjing 211198China

Ulcerative colitis (UC), a prevalent form of inflammatory bowel disease (IBD), may result from immune system dysfunction, leading to the sustained overproduction of reactive oxygen species (ROS) and subsequent cellular oxidative stress damage. Recent studies have identified both peroxisome proliferator-activated receptor-γ (PPARγ) and endoplasmic reticulum (ER) stress as critical targets for the treatment of IBD. Oroxyloside (C22H20O11), derived from the root of Scutellaria baicalensis Georgi, has traditionally been used in treating inflammatory diseases. In this study, we investigated the molecular mechanisms by which oroxyloside mitigates dextran sulfate sodium (DSS)-induced colitis. We examined the effects of oroxyloside on ROS-mediated ER stress in colitis, including the protein expressions of GRP78, p-PERK, p-eIF2α, ATF4, and CHOP, which are associated with ER stress. The beneficial impact of oroxyloside was reversed by the PPARγ antagonist GW9662 (1 mg·kg^(−1), i.v.) in vivo. Furthermore, oroxyloside decreased pro-inflammatory cytokines and ROS production in both bone marrow-derived macrophages (BMDM) and the mouse macrophage cell line RAW 264.7. However, PPARγ siRNA transfection blocked the anti-inflammatory effect of oroxyloside and even abolished ROS generation and ER stress activation inhibited by oroxyloside in vitro. In conclusion, our study demonstrates that oroxyloside ameliorates DSS-induced colitis by inhibiting ER stress via PPARγ activation, suggesting that oroxyloside might be a promising effective agent for IBD.

关键词： Oroxyloside ER stress PPARγ Colitis

Tunable VO_(2) cavity enables multispectral manipulation from visible to microwave frequencies

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Light(Science & Applications) 2024年第3期13卷 510-518页

作者： Hang Wei Jinxin Gu Tao Zhao Zhiyuan Yan He-Xiu Xu Shuliang dou Cheng-Wei Qiu Yao Li Center for Composite Materials and Structure Harbin Institute of TechnologyHarbin 150001China National University of Singapore Department of Electrical&Computer EngineeringSingapore 117583Singapore School of Chemical Engineering and Technology Harbin Institute of TechnologyHarbin 150001China Suzhou Laboratory Suzhou 215123China

Optical materials capable of dynamically manipulating electromagnetic waves are an emerging field in memories,optical modulators,and thermal management.Recently,their multispectral design preliminarily attracts much attention,aiming to enhance their efficiency and integration of functionalities.However,the multispectral manipulation based on these materials is challenging due to their ubiquitous wavelength dependence restricting their capacity to narrow wavelengths.In this article,we cascade multiple tunable optical cavities with selective-transparent layers,enabling a universal approach to overcoming wavelength dependence and establishing a multispectral platform with highly integrated functions.Based on it,we demonstrate the multispectral(ranging from 400 nm to 3 cm),fast response speed(0.9 s),and reversible manipulation based on a typical phase change material,vanadium dioxide.Our platform involves tandem VO_(2)-based Fabry–Pérot(F-P)cavities enabling the customization of optical responses at target bands independently.It can achieve broadband color-changing capacity in the visible region(a shift of~60 nm in resonant wavelength)and is capable of freely switching between three typical optical models(transmittance,reflectance,and absorptance)in the infrared to microwave regions with drastic amplitude tunability exceeding 0.7.This work represents a state-of-art advance in multispectral optics and material science,providing a critical approach for expanding the multispectral manipulation ability of optical systems.

关键词： spectral microwave visible

CO_(2) corrosion of X80 steel welded joints under micro-turbulence induced by welding reinforcement height

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Journal of Iron and Steel Research(International) 2024年第4期31卷 1015-1032页

作者： Xiao-hui dou Bin Li Zong-hao He Xin-wei Zhang Da-lei Zhang Yan Li School of Materials Science and Engineering China University of Petroleum(East China)Qingdao 266580ShandongChina School of Energy and Power Engineering Jiangsu UniversityZhenjiang 212013JiangsuChina

Corrosion failure accidents owing to flow erosion and pipeline corrosion frequently occur during transportation.The welding reinforcement height(WRH)can induce locally micro-turbulent flow field,which aggravates local corrosion of welded joints.A high wall shear stress(WsS)experimental setup was established to conduct the online electrochemical corrosion test.The influence of WRH sizes on local corrosion of welded joints was studied at different flow rates.The electrochemical signals of the local corrosion of X80 welded joints at different flow rates were monitored in real time using electrochemical impedance spectroscopy and wire beam microelectrode.In addition,the corrosion products composition and properties were analyzed.The results show that the micro-turbulent flow fields induced by the WRHs can enhance ion mass transfer near the welded joints.The corrosion products on the WRH surface also present different microscopic morphologies at different flow rates.In strong flow fields,the locally enhanced wsS can peel off the dense corrosion product partially,leading to the electrochemical distribution of large cathode and small anode,which accelerates the occurrence and development processes of the local corrosion of welded joints.The scientific guidelines for the corrosion protection of long-distance oil and gas pipelines can be potentially provided.

关键词： X80 steel welded joint Welding reinforcement height Micro-turbulence CO_(2)corrosion-Ion mass transfer

A comparison study on structure-function relationship of polysaccharides obtained from sea buckthorn berries using different methods:antioxidant and bile acid-binding capacity

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Food Science and Human Wellness 2024年第1期13卷 494-505页

作者： Qiaoyun Li Zuman dou Qingfei Duan Chun Chen Ruihai Liu Yueming Jiang Bao Yang Xiong Fu SCUT-Zhuhai Institute of Modern Industrial Innovation School of Food Science and EngineeringSouth China University of Technology381 Wushan RoadGuangzhou 510640China Guangzhou Institute of Modern Industrial Technology Nansha 511458China Guangdong Province key Laboratory for Green Processing of Natural Products and Product Safety Guangzhou 510640China Overseas Expertise Introduction Center for Discipline Innovation of Food Nutrition and Human Health(111 Center) Guangzhou 510640China Department of Food Science Stocking HallCornell UniversityIthaca 14853USA South China Botanical Garden Chinese Academy of SciencesGuangzhou 510650China

In this study,the structural characters,antioxidant activities and bile acid-binding ability of sea buckthorn polysaccharides(HRPs)obtained by the commonly used hot water(HRP-W),pressurized hot water(HRP-H),ultrasonic(HRP-U),acid(HRP-C)and alkali(HRP-A)assisted extraction methods were investigated.The results demonstrated that extraction methods had significant effects on extraction yield,monosaccharide composition,molecular weight,particle size,triple-helical structure,and surface morphology of HRPs except for the major linkage bands.Thermogravimetric analysis showed that HRP-U with filamentous reticular microstructure exhibited better thermal stability.The HRP-A with the lowest molecular weight and highest arabinose content possessed the best antioxidant activities.Moreover,the rheological analysis indicated that HRPs with higher galacturonic acid content and molecular weight showed higher viscosity and stronger crosslinking network(HRP-C,HRP-W and HRP-U),which exhibited stronger bile acid binding capacity.The present findings provide scientific evidence in the preparation technology of sea buckthorn polysaccharides with good antioxidant and bile acid binding capacity which are related to the structure affected by the extraction methods.

关键词： Sea buckthorn Extraction method Structure Rheological properties Antioxidant activity Bile acid binding capacity

Etching of quartz crystals in liquid phase environment:A review

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Nanotechnology and Precision Engineering 2024年第2期7卷 87-109页

作者： Yide Dong Yike Zhou Haizhou Huang Bosong Zhang Xihan Li Kaiwen Chen Litao Sun Guangbin dou SEU-fei Nano-Pico Center Key Laboratory of MEMS of Ministry of EducationSoutheast UniversityNanjing 210096People’s Republic of China Nanjing Jingxin Optoelectronics Research Institute Nanjing 210096People’s Republic of China

Quartz crystals are the most widely used material in resonant sensors,owing to their excellent piezoelectric and mechanical properties.With the development of portable and wearable devices,higher processing efﬁciency and geometrical precision are required.Wet etching has been proven to be the most efﬁcient etching method for large-scale production of quartz devices,and many wet etching approaches have been developed over the years.However,until now,there has been no systematic review of quartz crystal etching in liquid phase environments.Therefore,this article provides a comprehensive review of the development of wet etching processes and the achievements of the latest research in thisﬁeld,covering conventional wet etching,additive etching,laser-induced backside wet etching,electrochemical etching,and electrochemical discharge machining.For each technique,a brief overview of its characteristics is provided,associated problems are described,and possible solutions are discussed.This review should provide an essential reference and guidance for the future development of processing strategies for the manufacture of quartz crystal devices.

关键词： Quartz crystal Materials processing Wet etching Microfabrication Quartz MEMS