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Science China(Technological Sciences) 2024年第6期67卷 1923-1932页

作者： ZHao Tao SHI yan lu Kun xi xiang WU XueZhong xiao DingBang College of Intelligence Science and Engineering National University of Defense TechnologyChangsha410073China

The quality factor(Q factor)is a crucial performance parameter for *** this paper,a novel release method for highquality micro fused silica shell resonators with teeth-like tines with good surface morphology is *** method is based on femtosecond laser-assisted chemical ***,the optimal energy range of femtosecond laser modification is obtained through mechanism ***,the optimal parameters for a straight line and arc pattern are determined by optimizing the average output power,processing speed,and processing *** results demonstrate why edge breakage in rounded corners is easy under different ***,according to these conclusions,the processing is performed on a micro fused silica shell resonator with a Q factor exceeding 6 *** addition,subsurface damage is rare throughout the fabrication process,and the surface roughness of the released cross section reaches the nanometer *** improved Q factor helps suppress mechanical thermal noise and reduce zero bias and zero bias drift,constituting the primary method for enhancing the performance of the resonant gyroscope.

关键词： micro hemispherical resonator fused silica laser-assisted chemical etching quality factor

Recent Advances in Cobalt-Catalyzed Regio-or Stereoselective Hydrofunctionalization of Alkenes and Alkynes

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CCS Chemistry 2024年第5期6卷 1130-1156页

作者： yan Li xi lu Yao Fu Hefei National Research Center for Physical Sciences at the Microscale CAS Key Laboratory of Urban Pollutant ConversionAnhui Province Key Laboratory of Biomass Clean EnergyUniversity of Science and Technology of ChinaHefei 230026 Key Laboratory of Precision and Intelligent Chemistry Department of Applied ChemistrySchool of Chemistry and Materials ScienceUniversity of Science and Technology of ChinaHefei 230026

Hydrofunctionalization of alkenes and alkynes is increasingly important in preparing and modifying carbon-centered organic molecules such as pharmaceuticals,agrochemicals,andmaterial *** development of transition-metal-catalysts has revolutionized the hydrofunctionalization of unsaturated hydrocarbons,greatly improving the synthetic efficiency and selectivity of these *** recent years,notable progress has been achieved in low-cost metal-catalyzed alkene and alkyne hydrofunctionalization reactions following the utilization of traditional precious metal catalysts,including palladium,platinum,and ***-abundant cobalt catalysts,which are low in toxicity and exhibit unique reactivity and selectivity,are widely implemented in academic and industrial *** this review,we highlight recent examples of cobalt-catalyzed hydrofunctionalization of alkenes and alkynes to provide an overview of hydrofunctionalization methods,particularly hydroalkylation *** reactions greatly expand the scope and utility of cobalt-catalyzed couplings of carbon—carbon *** also highlight the mechanistic considerations and selective determinants *** hope our discussion will be informative for future developments in cobalt catalysis and hydrofunctionalization reactions.

关键词： hydrofunctionalization cobalt-catalysis alkene alkyne regioselectivity stereoselectivity

Carrier-Envelope-Phase Control of Single-Electron Transport in Coupled Quantum Dots

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Chinese Physics Letters 2013年第11期30卷 102-105页

作者： yanG Wen-xing CHEN Ai-xi BAI yan-Feng lu jia-Wei Department of Physics Southeast UniversityNanjing 210096 Department of Applied Physics School of Basic ScienceEast China Jiaotong UniversityNanchang 330013

We propose a scheme for controlling the coherent transport of a single electron through a closed three-level structure in coupled quantum *** coherent transport is externally controlled by applying a weak few-cycle pulse with an adjustable carrier-envelope phase(CEP).It is revealed numerically that there exists a significant dependence of the electron transport on the *** results illustrate the potential to utilize few-cycle pulses for the excitation in coupled quantum dot systems through control of the CEP,as well providing guidance in the design for possible experimental implementations.

关键词： coherent quantum utilize

Natural aging mechanism of buried polyethylene pipelines during long-term service

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Petroleum Science 2023年第5期20卷 3143-3156页

作者： Ying-Chun Chen yan-Feng Li yan xi Qiang Li Qi lu Jie yang Beijing University of Technology Beijing100124China xinjiang Inspection Institute of Special Equipment Urumqi830011XinjiangChina

Currently,accelerated aging tests are widely used to study the aging process of polyethylene ***,this approach can only simulate one or several main influencing factors in the natural environment,which are often quite different from the actual environment of the buried *** this study,five types of PE80 buried pipelines in service for 9e18 years were taken as the research object,while new PE80 pipelines were taken as the reference *** aging process and mechanism of polyethylene buried pipelines were studied through mechanical and chemical property tests and microstructural *** results showed that the pipeline exhibited cross-linking as the main aging mechanism after being in service for 0e18 *** aging degree and law of the inner and outer surface of the pipeline were compared,and the observed mechanism of both surfaces was *** 18 years in service,the elongation at the break of the pipe decreased by 16.2%,and the toughness of the matrix in the main collapse area of the tensile sample was the fundamental reason responsible for changes in the mechanical ***,after 18 years in service,the oxidation induction time of the pipeline was 25.7 min,which was 28.5% higher than the national standard *** were no potential safety hazards during continuous long-term *** results of this paper provide reference data and theoretical guidance for the aging process study of buried polyethylene pipelines.

关键词： Polyethylene Buried pipelines Long-term service Natural aging

Effect of propofol on generation of inflammatory mediator of monocytes

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Asian Pacific Journal of Tropical Medicine 2015年第11期8卷 940-945页

作者： Yun Nie yan-xi lu Li-Hong Lv Operating Room First People's Hospital of Ji'nan

Objective:To evaluate the effect of propofol with different concentrations on the expression of inflammatory mediators of mterleukin and tumor-necrosis factor- α(TNF- α) by stimulating the mouse primary monocytes and human monocytic cell line with lipopolysaccharide(LPS)and also discuss the effeet of propofol on the secretion of inflammatory mediator and its possible molecular ***:The mononuclear cells of mouse spleen were separated and then purified to obtain the primary *** dose-effect relationship of production of pro-inflammatory cytokines by monocytes which were stimulated by LPS,namely the monocytes were stimulated by the dose of 0-500 ng/mL for 24 *** was employed to detect the concentration of IL-6,TL-8 and TNF-α.The effect of propofol on the secretion of above pro-inflammatory cytokines by the monocytes was *** were divided into the control group,the 0.1%DMSO group,the LPS group and the treatment group with LPS + different dose of propofol(propofol 1-100 μg/mL).ELISA was employed to detect the concentration of IL-6,IL-8 and TNF-α.The change in the expression of important signaling molecules in Toll-like receptor and NF-κ B signaling pathway was detected after THP-1 cells were treated with ***:The concentration of TNF- α was(3 863±153)pg/mL after 12 h of stimulation by LPS and then its concentration was decreased *** the concentration of IL-6 and IL-8 was relatively high after 24 h of stimulation by LPS,(5 627±330) pg/mL and(1 626±200) pg/mL,*** propofol could inhibit the expression of IL-6,IL-8 and TNF- α caused by *** the intervention treatment of 50 μg/mL propofol,the concentration of IL-6,IL-8 and TNF-α was significantly decreased(Plusions:The propofol can inhibit the expression of TLR-4 and NF-κ B to inhibit the activation of p38 and the expression of pro-inflammatory cytokines.

关键词： Propofol LPS IL-6 IL-8 TNF-α Anti-inflammation

2-D FluID SIMULATION OF DUAL-FREQUENCY CAPACITIVELY COUPLED PLASMA

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Journal of Hydrodynamics 2009年第6期21卷 814-819页

作者： lu Yi-jia yan Da-qiang CHEN Yao-song LTCS and College of Engineering Peking University Beijing 100871 China

Dual-frequency aegon discharge at 100 m Torr is modeled with a 2-D fluid model in this study. The plate gap of the system is 20 ram, and discharges are modeled at High Frequency （HF） 40 MHz, 60 MHz, 80 MHz, Low Frequency （LF） 2 MHz, 5 MHz, 10 MHz, low-frequency voltage 50 V, 75 V, 100 V and high-frequency voltage 200 V, respectively. The spatial distribution of electron density and ion density and the periodic evolution of instantaneous electric potential in bulk plasma and sheath are discussed. The numerical results show that plasma density increases with HFs and LFs and LF voltage, while HFs has more effect on the density. It is concluded that improving the ratio of HFs/LFs and increasing LF voltages is a method to gain high density and high ion bombardment energy simultaneously based on the analysis of electric potential distribution.

关键词： dual frequency CCP discharge 2-D fluid model

Natriuretic peptide family as diagnostic/prognostic biomarker and treatment modality in management of adult and geriatric patients with heart failure： remaining issues and challenges

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Journal of Geriatric Cardiology 2018年第8期15卷 540-546页

作者： Zhen-lu ZHANG Ran LI Fei-yan yanG Lei xi Department of Clinical Laboratory Wuhan Asia Heart Hospital Wuhan University Wuhan China Department of Cardiology The Central Hospital of Wuhan Tongji Medical College Huazhong University of Science and Technology Wuhan China Division of Cardiology Pauley Heart Center Virginia Commonwealth University Richmond VA United States

B-type natriuretic peptide （BNP） and N-terminal proBNP （NT-proBNP）, the key members of natriuretic peptide family have been rec- ommended as the gold standard biomarkers for the diagnosis and prognosis of heart failure （HF） according to the current clinical guidelines. However, recent studies have revealed many previously unrecognized features about the natriuretic peptide family, including more accurate utilization of BNP and NT-proBNP in diagnosing HF. The pathophysiological mechanisms behind natriuretic peptide release, breakdown, and clearance are very complex and the diverse nature of circulating natriuretic peptides and fragments makes analytical detection particu- larly challenging. In addition, a new class of drug therapy, which works via natriuretic peptide family, has also been considered promising for cardiology application. Under this context, our present mini-review aims at providing a critical analysis on these new progresses on BNP and NT-proBNP with a special emphasis on their use in geriatric cardiology settings. We have focused on several remaining issues and chal- lenges regarding the clinical utilization of BNP and NT-proBNP, which include：（1） Different prevalence and diagnostic/prognostic values of BNP isoforms; （2） methodological issues on detection of BNP; （3） glycosylation of proBNP and its effect on biomarker testing; （4） specificity and comparability of BNP/NT-proBNP resulted from different testing platforms; （5） new development of natriuretic peptides as HF treatment modality; （6） BNP paradox in HF; and （7） special considerations of using BNP/NT-proBNP in elderly HF patients. These practical discussions on BNP/NT-proBNP may be instrumental for the healthcare providers in critically interpreting laboratory results and effective management of the HF patients.

关键词： Angiotensin-renin-neprilysin-inhibitors Biomarker BNP Heart failure NT-proBNP

MXene@Co hollow spheres structure boosts interfacial polarization for broadband electromagnetic wave absorption

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Journal of Materials Science & Technology 2024年第9期176卷 167-175页

作者： yan Zhang Xuehua Liu Zhiqiang Guo Chenyu jia Feng lu Zirui jia Guanglei Wu Institute of Materials for Energy and Environment State Key Laboratory of Bio-fibers and Eco-textilesCollege of Materials Science and EngineeringQingdao UniversityQingdao 266071China Technical Center of Qingdao Customs Qingdao 266002China College of Chemistry and Chemical Engineering Qingdao UniversityQingdao 266071China

MXene is considered as a candidate for preparing high-performance electromagnetic wave absorbing materials due to its large specific surface area,rich surface modification groups,and unique metal ***,the impedance matching problem caused by its high conductivity and easy stacking properties is a limiting *** this study,a self-assembling-etching-anchoring growth method was proposed to prepare MXene@Co electromagnetic wave absorbing *** hollow structure of MXene microspheres constructed with PMMA as a hard template is conducive to optimizing impedance matching and surface *** addition,MXene@Co exhibits abundant heterogeneous interfaces,enhancing the interfacial polarization phenomenon during electromagnetic wave ***,the surfaceanchored growth of magnetic Co particles forms a magnetic network,which provides a strong magnetic loss capability for the *** hollow structure design significantly enhances the wave absorption performance compared to conventional MXene@Co composites,with a minimum reflection loss of−57.32 dB(effective absorption bandwidth of 5.2 GHz)when the thickness is 2.5 mm(2.2 mm).This work provides a meaningful reference for the design of MXene-based electromagnetic wave absorbing materials.

关键词： MXene@Co microspheres Hollow structure Impendance matching Electromagnetic wave absorption

Enhancement of β-Phase Crystal Content of Poly(vinylidene fluoride)nanofiber Web by Graphene and Electrospinning Parameters

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Chinese Journal of Polymer Science 2020年第11期38卷 1239-1247,I0008页

作者： lu Jin yan Zheng Ze-Kun Liu jia-Shen Li yang-Pei-Qi Yi yang-yang Fan lu-lu Xu Yi Li Department of Materials School of Natural SciencesThe University of ManchesterManchester Ml 39PLU.K. School of Fashion Zhongyuan University of TechnologyZhengzhou 450007China

Electrospun poly(vinylidene fluoride)(PVDF)nanofiber web has been widely utilized as a functional material in various flexible sensors and generators due to its high piezoelectricity,ease processability,and low *** all the crystalline phases of PVDF,β-phase is a key property for PVDF nano fiber web,because the con tent of β-phase is directly proporti onal to piezoelectric performa nee of PVDF nano fiber ***,the impact of graphe ne con tent(GC),tip-to-collector dista nee(TCD),and rotational speed of collector(RSC),as well as their interactions on theβ-phase formation of PVDF nano fiber web is systematically investigated via design of experime ntal *** fraction of each crystalline phase of PVDF nano fiber web is calculated by FTIR spectra,and the crystallinity is determined by XRD *** influences of GC,TCD,and RSC on both β-phase fraction and crystallinity of PVDF nanofiber are analyzed using Minitab *** results show that GC,TCD,and RSC all have significa nt effect on the β-phase content of PVDF nano fiber web,and GC is the most significant *** addition,an optimal electrospinning condition(GC=1 wt%,TCD=4 cm,and RSC=2000 r·min^-1)to fabricate high 0-phase crystallinity of PVDF nanofiber web is drawn,under which the crystallinity can reach 41.7%.The contributions in this study could provide guidanee for future research on fabricating high performance PVDF nanofiber web based sensors or generators.

关键词： Graphene Electrospinning Poly(vinylidene fluoride) Design of experiment βCrystal phase

Synthesis of Thieno[3,4-b]pyrazine-based Alternating Conjugated Polymers via Direct Arylation for Near-infrared OLED Applications

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Chinese Journal of Polymer Science 2022年第2期40卷 138-146页

作者： Ze-Wang He Qiang Zhang Chen-xi Li Hong-Ting Han yan lu School of Materials Science&Engineering Tianjin Key Laboratory for Photoelectric Materials and DevicesKey Laboratory of Display Materials&Photoelectric DevicesMinistry of EducationTianjin University of TechnologyTianjin 300384China College of Chemistry Nankai UniversityTianjin 300071China

Three alternating conjugated polymers,namely PFTP,PCz TP,and PSi TP,which combine a thieno[3,4-b]pyrazine(TP)unit with different benzene-based donor units such as 9,9-dioctylfluorene,9-heptadecyl-9H-carbazole and 5,5-dioctyl-5H-dibenzo[b,d]silole,were synthesized in good yield(>85%)and high molecular weight up to Mn=5.82×10^(4) via direct arylation polymerization(DAr P).All the resultant polymers exhibit moderate bandgap of about 1.80 e V and strong deep red/near-infrared emitting in the solid *** them,the PSi TP-based electroluminescence(EL)devices with an architecture of ITO/PEDOT:PSS/PTAA/emitting layer/TPBi/Li F/Al give the best performance with a maximum luminance of 2543 cd/m^(2) at 478 m A/cm^(2).This work expands the application scope of high-performance conjugated polymers which can be synthesized by DAr P.

关键词： Thieno[3 4-b]pyrazine Alternating D-A structure Direct arylation polymerization Conjugated polymer Organic light-emitting diodes