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Wind induced deformation and vibration of a Platanus acerifolia leaf

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Acta Mechanica Sinica 2012年第3期28卷 583-594页

作者： chuan-Ping Shao Ye-Jun Chen Jian-zhong lin China Jiliang University 310018 HangzhouChina

Deformation and vibration of twig-connected sin- gle leaf in wind is investigated experimentally. Results show that the Reynolds number based on wind speed and length of leaf blade is a key parameter to the aerodynamic prob- lem. In case the front surface facing the wind and with an in- crease of Reynolds number, the leaf experiences static defor- mation, large amplitude and low frequency sway, reconfigu- ration to delta wing shape, flapping of tips, high frequency vibration of whole leaf blade, recovery of delta wing shape, and twig-leaf coupling vibration. Abrupt changes from one state to another occur at critical Reynolds numbers. In case the back surface facing the wind, the large amplitude and low frequency sway does not occur, the recovered delta wing shape is replaced by a conic shape, and the critical Reynolds numbers of vibrations are higher than the ones correspond- ing to the case with the front surface facing the wind. A pair of ram-horn vortex is observed behind the delta wing shaped leaf. A single vortex is found downstream of the conic shaped leaf. A lift is induced by the vortex, and this lift helps leaf to adjust position and posture, stabilize blade distortion and reduce drag and vibration.

关键词： Tree leaf. Wind. Deformation Vibration

Methane sensor based on palladium/MWNT nanocomposites

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Chinese Chemical Letters 2009年第5期20卷 608-610页

作者： zhong Ping li Yong Guo Suo Zhu Wu Shao Min Shuang chuan Dong Research Center of Environmental Science and Engineering School of Chemistry and Chemical Engineering Shanxi University Taiyuan 030006 PR China School of Chemistry Shanxi Datong University Datong 037009 PR China

Methane gas sensor was fabricated based on electrocatalytic properties of the Pd/MWNT nanocomposites on indium tin oxide （ITO） glass substrates. A linear response for methane was obtained in the range of 0-16% （v/v） with a detection limit of 0.167% （v/ v） and R.S.D. of 4.1%. After 100 times sensing or stable stored more than 12 months in atmosphere, unconspicuous measurable decrease was observed. The response time was less than 60 s at room temperature and ambient pressure. Some common potential interferents in samples such as N2, CO, CO2, ethane, propane, pentane, methanol, ethanol, H2 and NH3 were investigated and all the effects were less than 5% on the response for 3.0% （v/v） methane. The sensor was applied to methane determinations in man-made gas samples, the results are satisfied.

关键词： Methane Gas sensor PaUadium/MWNTs Electrocatalysis

miR-212-3p靶向MAPK3调控骨髓间充质干细胞的衰老

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中国组织工程研究 2025年第13期29卷 2690-2697页

作者：钟丽颖李顺东王聪长沙市第三医院老年病科湖南省长沙市410015

背景:骨质疏松症患者的骨髓间充质干细胞表现出明显衰老状态,并且细胞活性及成骨分化水平显著降低。miR-212-3p能够抑制人骨髓间充质干细胞的成骨分化,但其对骨髓间充质干细胞衰老调控的作用及机制尚不明确。目的:研究miR-212-3p通过靶... 详细信息

背景:骨质疏松症患者的骨髓间充质干细胞表现出明显衰老状态,并且细胞活性及成骨分化水平显著降低。miR-212-3p能够抑制人骨髓间充质干细胞的成骨分化,但其对骨髓间充质干细胞衰老调控的作用及机制尚不明确。目的:研究miR-212-3p通过靶向丝裂原活化蛋白激酶3(mitogen-activated protein kinase 3,MAPK3)对骨髓间充质干细胞衰老的影响及其机制。方法:体外分离培养大鼠骨髓间充质干细胞,收集第3代进行以下实验:①分2组培养:对照组加入完全培养基,造模组加入含H_(2)O_(2)的完全培养基培养,培养72 h后,检测细胞中β-半乳糖苷酶活性、miR-212-3p和MAPK3 mRNA表达,以及MAPK3、p16和p21蛋白表达。②分3组培养:对照组、抑制物对照组、miR-212-3p抑制物组,转染24 h后,检测细胞中miR-212-3p、MAPK3 mRNA表达及MAPK3蛋白表达。③采用双荧光素酶报告基因联合qRT-PCR和Western blot验证miR-212-3p与MAPK3靶向调控作用。④分组培养:分为对照抑制物组、miR-212-3p抑制物组、miR-212-3p抑制物+干扰对照组、miR-212-3p抑制物+MAPK3干扰组,转染24 h后,检测细胞中MAPK蛋白与mRNA表达。分为对照组、H_(2)O_(2)组、H_(2)O_(2)+对照抑制物组、H_(2)O_(2)+miR-212-3p抑制物组、H_(2)O_(2)+miR-212-3p抑制物+干扰对照组、H_(2)O_(2)+miR-212-3p抑制物+MAPK3干扰组,细胞转染24 h后再加入H_(2)O_(2)培养72 h,检测细胞中衰老相关β-半乳糖苷酶活性、p16和p21蛋白表达。结果与结论:①与对照组比较,造模组β-半乳糖苷酶活性、miR-212-3p mRNA表达及p16、p21蛋白表达升高(P<0.05),MAPK3 mRNA和蛋白表达降低(P<0.05)。②与对照组比较,miR-212-3p抑制物组细胞中miR-212-3p mRNA表达降低(P<0.05),MAPK3 mRNA与蛋白表达升高(P<0.05)。③双荧光素酶报告基因实验证实,MAPK3是miR-212-3p下游靶基因。④与对照抑制物组比较,miR-212-3p抑制物组细胞中MAPK3 mRNA和蛋白表达升高(P<0.05);与miR-212-3p抑制物组比较,miR-212-3p抑制物+MAPK3干扰组细胞中MAPK3 mRNA和蛋白表达降低(P<0.05)。与H_(2)O_(2)+对照抑制物组比较,H_(2)O_(2)+miR-212-3p抑制物组β-半乳糖苷酶活性降低(P<0.05);与H_(2)O_(2)+miR-212-3p抑制物组比较,H_(2)O_(2)+miR-212-3p抑制物+MAPK3干扰组β-半乳糖苷酶活性升高(P<0.05)。与H_(2)O_(2)+对照抑制物组比较,H_(2)O_(2)+miR-212-3p抑制物组细胞中p16和p21蛋白表达降低(P<0.05);与H_(2)O_(2)+miR-212-3p抑制物组比较,H_(2)O_(2)+miR-212-3p抑制物+MAPK3干扰组细胞中p16和p21蛋白表达升高(P<0.05)。⑤结果表明,下调miR-212-3p可抑制大鼠骨髓间充质干细胞衰老,其作用机制可能是通过靶向上调MAPK3表达实现的。

关键词：骨髓间充质干细胞细胞衰老 miR-212-3p 丝裂原活化蛋白激酶3 β-半乳糖苷酶

Effect of supports on the redox performance of pyrite cinder in chemical looping combustion

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Chinese Journal of Chemical Engineering 2021年第9期34卷 168-174页

作者： zhong Ma chuan Yuan Shuai Zhang Yonggang Lu Junhui Xiong School of Energy&Power Engineering Jiangsu UniversityZhenjiang 212013China State Key Laboratory of High-Efficiency Utilization of Coal and Green Chemical Engineering Ningxia UniversityYinchuan 750021China Key Laboratory of Energy Thermal Conversion and Control of Ministry of Education School of Energy and EnvironmentSoutheast UniversityNanjing 210096China

Chemical looping combustion(CLC)is a clean and efficient flame-free combustion technology,which combust the fuels by lattice oxygen from a solid oxygen carrier with inherent CO_(2)*** development of oxygen carriers with low cost and high redox performance is crucial to the whole efficiency of CLC *** the solid by-product from the sulfuric acid production,pyrite cinder presented excellent redox performance as an oxygen carrier in CLC *** main components in pyrite cinder are Fe_(2)O_(3),CaSO_(4),Al_(2)O_(3)and SiO_(2)in which Fe_(2)O_(3)is the active component to provide lattice *** order to systematic investigate the functions of supports(CaSO_4,Al_(2)O_(3)and SiO_(2))in pyrite cinder,three oxygen carriers(Fe_(2)O_(3)-CaSO_(4),Fe_(2)O_(3)-Al_(2)O_(3)and Fe_(2)O_(3)-SiO_(2))were prepared and evaluated in this *** results showed that Fe_(2)O_(3)-CaSO_(4) displayed high redox activity and cycling stability in the multiple redox ***,both Fe_(2)O_(3)-Al_(2)O_(3)and Fe_(2)O_(3)-SiO_(2)experienced serious deactivation during redox *** indicated that the inert Fe-Si solid solution(Fe_(2)SiO_(4))was formed in the spent Fe_(2)O_(3)-SiO_(2)sample,which decreased the oxygen carrying capacity of this *** XPS results showed that the oxygen species on the surface of Fe_(2)O_(3)-CaSO_(4) could be fully recovered after the 20 redox *** can be concluded that CaSO_(4) is the key to the high redox activity and cycling stability of pyrite cinder.

关键词： Chemical looping Pyrite cinder Supports Fixed-bed Redox performance Waste treatment

Junction Current Drift Effect of the Cu/Porous Si Device Prepared by Electrodeposition

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Chinese Physics Letters 1997年第2期14卷 124-127页

作者： WANG Guan-zhong li Peng MA Yu-rong FANG Rong-chuan Department of Physics University of Science and Technology of ChinaHefei 230026

A novel characteristic of the junction current drift effect in the Cu/porous silicon(Cu/PS)device prepared by electrodeposition in which Cu ions were deposited on porous silicon is *** junction current increases with time and gradually approaches to a saturated value when a certain forward bias is applied on the Cu/PS ***,after the bias was withdrawn for a period,a different drift process was observed when the same bias was applied *** drifttime constant and the initial current of latter drift process depend on cut-off *** an effect is explained in terms of the model that only part of electrons from porous silicon contributes to the junction current while other electrons are captured by the traps in the interface between Cu and porous silicon in the Cu/PS device.

关键词： porous effect Porous

湿地表层底泥溶解性有机质荧光组分特征及与真菌群落相关性

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光谱学与光谱分析 2025年第1期45卷 191-196页

作者：史传奇李艳孟令波胡钰金梁哈尔滨学院黑龙江省寒区湿地生态与环境研究重点实验室黑龙江哈尔滨150086 北京市农林科学院植物营养与资源环境研究所北京100097 东北农业大学资源与环境学院黑龙江哈尔滨150038

溶解性有机质(DOM)和微生物群落间具有紧密联系,DOM为微生物提供营养,微生物代谢可转化DOM,两者间相互作用共同影响着生态系统的物质循环与能量流动。采集北方寒区天然湿地(河流湿地,HL;湖泊湿地,HP)和人工湿地(水田,ST;鱼塘,YT)表层(0~... 详细信息

溶解性有机质(DOM)和微生物群落间具有紧密联系,DOM为微生物提供营养,微生物代谢可转化DOM,两者间相互作用共同影响着生态系统的物质循环与能量流动。采集北方寒区天然湿地(河流湿地,HL;湖泊湿地,HP)和人工湿地(水田,ST;鱼塘,YT)表层(0~15 cm)底泥样品,采用三维荧光光谱法和高通量测序技术,揭示不同类型湿地表层底泥DOM荧光光谱及真菌群落特征,并进一步分析其相关性。结果表明:表层底泥DOM荧光光谱共识别出4种荧光组分,包括类富里酸(C1)、类胡敏酸(C2)和类蛋白质(类色氨酸C3和类酪氨酸C4)。C1和C2成显著正相关,而与类蛋白质间相关性不显著。C1的相对浓度高于C2,C3和C4的相对浓度接近。YT中DOM浓度相对高于其余样品,HL和HP中C2和类蛋白质相对浓度具有显著差异,ST和YT中C1、C2和C3的相对浓度均具有显著差异。湿地表层底泥真菌群落优势门(除未分类类群)为子囊菌门(Ascomycota)、担子菌门(Basidiomycota)、罗兹菌门(Rozellomycota)。YT中真菌群落Chao1丰富度指数、Shannon多样性指数显著较低,而Simpson优势度指数显著较高,HP中Shannon多样性指数显著高于其余样品。C1、C2与真菌群落多样性显著相关,C2与真菌群落组成显著相关,而类蛋白质与真菌群落无显著相关性。C1、C2与子囊菌门均成显著正相关,C1与壶菌门(Chytridiomycota)和单毛壶菌门(Monoblepharomycota)成显著负相关,C2与担子菌门、罗兹菌门、壶菌门、单毛壶菌门均成显著负相关。因此,真菌群落对DOM相对大分子量荧光组分的相对浓度具有显著影响。针对北方寒区典型湿地表层底泥DOM荧光光谱特征及与真菌群落相关性进行分析,为湿地环境监测与评价提供基础数据,并为湿地合理利用提供理论参考。

关键词：三维荧光光谱溶解性有机质荧光组分真菌

Monoexponential Microsecond Decay of Blue Photoluminescence in Aged Porous Silicon Prepared with Ar^(+) 488nm

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Chinese Physics Letters 1998年第5期15卷 382-384页

作者： li Peng MA Yu-rong WANG Guan-zhong FANG Rong-chuan Department of Physics University of Science and Technology of ChinaHefei 230026 Laboratory of Excited State Processes Changchun Institute of PhysicsChinese Academy of SciencesChangchun 130021

Blue photoluminescence is observed in aged porous silicon samples anodized under Ar^(+)488 nm laser *** samples have been undergone any heating treatment *** nanosecond and microsecond decay of blue photoluminescence have been *** show a good monoexponential microsecond decay with lifetimes of about 5.3μ*** excitation spectra of blue and red Photoluminescence indicate there is a large Stokes shift(about 800-900meV)in the excitation spectra of red photoluminescence while no this marked Stokes shift in that of blue *** possible origin of the photoluminescence is discussed based on the experimental results.

关键词： process. exponential Photoluminescence

Thickness and sp3 bond modulation of（Ti/tetrahedral amorphous carbon）_n multilayer coatings

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Tungsten 2025年第1期 152-160页

作者： Zhi-Jun Xie Jia-lin li ling Gong Xiang-li zhong Hong-Jia Song Jin-Bin Wang National-Provincial Laboratory of Special Function Thin Film Materials School of Materials Science and Engineering Xiangtan University

The durability of wear-resistant tetrahedral amorphous carbon（ta-C） coatings is intimately linked to their thickness and the concentration of *** enhance the lifespan of the coatings,we have prepared a multilayer coating consisting of alternating layers of Ti and ta-C,denoted as（Ti/ta-C）_n,using arc ion plating.A multi-layer structure in conjunction with stage cooling is employed to enhance the thickness and promote *** results indicate that the ID/IGvalue,representing the ratio of the intensity of the D peak to that of the G peak in Raman spectroscopy,decreases from 0.85 when no stage cooling is applied to 0.35 when stage cooling is employed,suggesting an enhancement in the fraction of sp3bonds within the *** obtained（Ti/ta-C）_n multilayer coating without peeling off has a maximum thickness of 1.14 μm,which is almost double that of the ta-C coating single layer *** the same time,the coating has a low coefficient of friction,down to 0.069,and maintains excellent friction properties with a wear rate of 3.4×10-6mm3·N-1·*** results conclusively show that the preparation technology can enhance both thickness and sp3bonding in ta-C coatings,significantly expanding their utility across tools,molds,and precision engineering components.

关键词：

SERS nanoprobes for bio-application

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Frontiers of Chemical Science and Engineering 2015年第4期9卷 428-441页

作者： Han-Wen Cheng Jin Luo chuan-Jian zhong School of Chemical and Environmental Engineering Shanghai Institute of Technology Shanghai 201418 China Department of Chemistry State University of New York at Binghamton Binghamton NY 13902 USA

The ability to tune the size, shape, composition and surface properties impart nanoparticles with the desired functions for bio-application. This article highlights some of the recent examples in the exploration of metal （e.g., gold and silver） nanoparticles, especially those with magnetic properties and bio-conjugated structures, as theranostic nanoprobes. Such nanoprobes exhibit tunable optical, spectroscopic, magnetic, and electrical properties for signal amplifications. Examples discussed in this article will focus on the nanoproble-enhanced colorimetric detection and surface enhanced Raman scattering （SERS） detection of biomarkers or biomolecules such as proteins and DNAs. The understanding of factors controlling the biomolecular interactions is essential for the design of SERS nanoprobes with theranostic functions.

关键词： functional nanoprobes metal nanoparticles,surface-enhanced Raman scattering bio-conjugation mag-netic properties theranostic materials