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Microscopic structured light 3D imaging via a scattering lens
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作者 Wenjing Zhao Wei Chang +3 位作者 Youtao Wang Aiping Zhai Fei Liu Dong Wang 《Advanced Photonics Nexus》 2025年第6期12-18,共7页
Transforming a scattering medium into a lens for imaging very simple binary objects is possible;however,it remains challenging to image complex grayscale objects,let alone measure 3D continuous distribution objects.He... Transforming a scattering medium into a lens for imaging very simple binary objects is possible;however,it remains challenging to image complex grayscale objects,let alone measure 3D continuous distribution objects.Here,we propose and demonstrate the use of a ground glass diffuser as a scattering lens for imaging complex grayscale fringes,and we employ it to achieve microscopic structured light 3D imaging(MSL3DI).The ubiquitous property of the speckle patterns permits the exploitation of the scattering medium as an ultra-thin scattering lens with a variable focal length and a flexible working distance for microscale object measurement.The method provides a light,flexible,and cost-effective imaging device as an alternative to microscope objectives or telecentric lenses in conventional MSL3DI systems.We experimentally demonstrate that employing a scattering lens allows us to achieve relatively good phase information and robust 3D imaging from depth measurements,yielding measurement accuracy only marginally lower than that of a telecentric lens,typically within approximately 10μm.Furthermore,the scattering lens demonstrates robust performance even when the imaging distance exceeds the typical working distance of a telecentric lens.The proposed method facilitates the application of scattering imaging techniques,providing a more flexible solution for MSL3DI. 展开更多
关键词 3D imaging scattering lens microscopic structured light imaging scattering imaging microscale object measurement.
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Quantitative determination of PFC3D microscopic parameters 被引量:7
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作者 LI Zhuo RAO Qiu-hua 《Journal of Central South University》 SCIE EI CAS CSCD 2021年第3期911-925,共15页
It is important to calibrate micro-parameters for applying partied flow code(PFC)to study mechanical characteristics and failure mechanism of rock materials.Uniform design method is firstly adopted to determine the mi... It is important to calibrate micro-parameters for applying partied flow code(PFC)to study mechanical characteristics and failure mechanism of rock materials.Uniform design method is firstly adopted to determine the microscopic parameters of parallel-bonded particle model for three-dimensional discrete element particle flow code(PFC3D).Variation ranges of microscopic of the microscopic parameters are created by analyzing the effects of microscopic parameters on macroscopic parameters(elastic modulus E,Poisson ratio v,uniaxial compressive strengthσc,and ratio of crack initial stress to uniaxial compressive strengthσci/σc)in order to obtain the actual uniform design talbe.The calculation equations of the microscopic and macroscopic parameters of rock materials can be established by the actual uniform design table and the regression analysis and thus the PFC3D microscopic parameters can be quantitatively determined.The PFC3D simulated results of the intact and pre-cracked rock specimens under uniaxial and triaxial compressions(including the macroscopic mechanical parameters,stress−strain curves and failure process)are in good agreement with experimental results,which can prove the validity of the calculation equations of microscopic and macroscopic parameters. 展开更多
关键词 quantitative relationship of microscopic and macroscopic parameters uniform design method three-dimensional particle flow code(PFC3D) ROCK
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静电纺丝法制备Pr^(3+)掺杂BaTiO_(3)纳米纤维及其光学性能研究 被引量:1
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作者 陈铃 关员路 +4 位作者 刘昊宇 王娇 裴清豪 杨柳 刘少辉 《功能材料》 北大核心 2025年第6期6216-6220,6228,共6页
为了提升钛酸钡材料的发光性能,基于稀土元素掺杂的理念,采用静电纺丝工艺制备出Pr^(3+)掺杂BaTiO_(3)一维纳米纤维,分析了稀土元素Pr掺杂浓度对一维纳米纤维相结构、形貌、发光性能的影响,并对其影响因素及机理进行分析。测试结果表明... 为了提升钛酸钡材料的发光性能,基于稀土元素掺杂的理念,采用静电纺丝工艺制备出Pr^(3+)掺杂BaTiO_(3)一维纳米纤维,分析了稀土元素Pr掺杂浓度对一维纳米纤维相结构、形貌、发光性能的影响,并对其影响因素及机理进行分析。测试结果表明:静电纺丝制备出的Pr^(3+)掺杂BaTiO_(3)纳米粉体具有良好的一维纳米纤维形貌,在较低Pr^(3+)掺杂浓度时,稀土元素Pr^(3+)能够进入BaTiO_(3)粉体的晶格,并不形成新的杂相,荧光性能测试结果表明:Pr^(3+)掺杂可以显著提高BaTiO_(3)一维纳米纤维的发光性能,Pr^(3+)掺杂可以提供相关的电子跃迁能级,荧光峰发射峰位于497、502、539、613、659 nm可以归因于^(3)P_(0)→^(3)H_(4)、^(3)P_(1)→^(3)H_(5)、^(3)P_(0)→^(3)H_(6)、^(3)P_(0)→^(3)F_(2)的能级跃迁,并且随着稀土元素Pr^(3+)掺杂浓度的逐渐增加,Ba 1-x Pr x TiO_(3)一维纳米纤维的荧光发光强度呈现先提高后降低,此现象可以归因于当较低Pr^(3+)浓度掺杂时,BaTiO_(3)晶格与Pr^(3+)间的相互作用,而Pr^(3+)浓度掺杂较高时,BaTiO_(3)晶格内与Pr^(3+)之间的距离变小,导致部分能量转移到猝灭中心,从而导致Pr^(3+)掺杂BaTiO_(3)一维纳米纤维荧光发光强度降低。 展开更多
关键词 BaTiO_(3) 一维纳米纤维 微观形貌 光学性能 Pr^(3+)掺杂 微观机理
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Microscopic phase-field modeling of atomic anti-site behaviors in precipitation progress of Ni_3(AlFe) 被引量:1
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作者 梁敏洁 廖海洪 +1 位作者 丁文江 陈铮 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2010年第10期1963-1967,共5页
The effects of temperature on atomic anti-site behaviors in L12-Ni3(AlFe) phases were studied using microscopic phase-field dynamic model in precipitation progress of Ni75Al20Fe5 alloy.The results show that with the i... The effects of temperature on atomic anti-site behaviors in L12-Ni3(AlFe) phases were studied using microscopic phase-field dynamic model in precipitation progress of Ni75Al20Fe5 alloy.The results show that with the increase of temperature,the formation of NiAl and AlNi anti-sites is much easier in Ni3(AlFe),and Ni and Al anti-site atoms show clearly stronger temperature-dependent than Fe anti-site atoms.The evolution progress of anti-site atoms is completed at the initial growth stage of L12-Ni3(AlFe) phases.The site occupation probabilities of Ni atoms on the sublattice A(NiNi,face centers sites of FCC),and Al and Fe atoms on the sublattice B(AlAl and FeAl,corners sites of FCC) all present the degressive tendency with the temperature increasing.Fe atoms mainly prefer to occupy the Al sublattice at the whole temperature range. 展开更多
关键词 anti-site microscopic phase-field PRECIPITATION Ni3(AlFe)
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Electron Microscopic In-situ Observation for Preparation of Ultrafine La_2O_3 Nanophase Powder 被引量:1
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作者 高愈尊 李永洪 张泰宋 《Journal of Rare Earths》 SCIE EI CAS CSCD 1996年第3期206-209,共4页
In-situ observation in high voltage electron microscope(HVEM) was used to investigate transformation from amorphous La(OH)3 to nanophase La2O3. Electron diffraction pattern indicates that the transition temperature fr... In-situ observation in high voltage electron microscope(HVEM) was used to investigate transformation from amorphous La(OH)3 to nanophase La2O3. Electron diffraction pattern indicates that the transition temperature from La(OH)3 to nanophase La2O3 is 400 ℃. Particle sizes for nanophase La2O3 are from 20 to 50 nm. 展开更多
关键词 La_2O_3 NANOPHASE Insitu observation High voltage electron microscope
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Sorting Gold and Sand(Silica) Using Atomic Force Microscope-Based Dielectrophoresis 被引量:1
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作者 Chungman Kim Sunghoon Hong +3 位作者 Dongha Shin Sangmin An Xingcai Zhang Wonho Jhe 《Nano-Micro Letters》 SCIE EI CAS CSCD 2022年第2期1-11,共11页
Additive manufacturing-also known as 3D printing-has attracted much attention in recent years as a powerful method for the simple and versatile fabrication of complicated three-dimensional structures.However,the curre... Additive manufacturing-also known as 3D printing-has attracted much attention in recent years as a powerful method for the simple and versatile fabrication of complicated three-dimensional structures.However,the current technology still exhibits a limitation in realizing the selective deposition and sorting of various materials contained in the same reservoir,which can contribute significantly to additive printing or manufacturing by enabling simultaneous sorting and deposition of different substances through a single nozzle.Here,we propose a dielectrophoresis(DEP)-based material-selective deposition and sorting technique using a pipette-based quartz tuning fork(QTF)-atomic force microscope(AFM) platform DEPQA and demonstrate multi-material sorting through a single nozzle in ambient conditions.We used Au and silica nanoparticles for sorting and obtained 95% accuracy for spatial separation,which confirmed the surfaceenhanced Raman spectroscopy(SERS).To validate the scheme,we also performed a simulation for the system and found qualitative agreement with the experimental results.The method that combines DEP,pipette-based AFM,and SERS may widely expand the unique capabilities of 3D printing and nano-micro patterning for multi-material patterning,materials sorting,and diverse advanced applications. 展开更多
关键词 Dielectrophoresis-empowered Pipette/AFM platform On-demand materials sorting Additive 3D printing Multimaterial nano-patterning Nanopipette-based atomic force microscope
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Microscopic Observation and Stability Study on the Fe_3s_4 Nanocrystals Synthesizedunder Thermal and Humid Conditions
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作者 GAO Shang HUANG Fei +6 位作者 SONG Dan LI Guanglu LIU Jia GAO Wenyuan LIU Qiang FENG Taiwei ZHAO Ran 《矿物学报》 CAS CSCD 北大核心 2013年第S1期26-26,共1页
Fe3S4 is important magnetic mineral that widely exists in the sediments of lakes and oceans. It can not only instruct reducing environment that contains organic matter and sulfate, but also provide paleomagnetic signa... Fe3S4 is important magnetic mineral that widely exists in the sediments of lakes and oceans. It can not only instruct reducing environment that contains organic matter and sulfate, but also provide paleomagnetic signal for paleoenvironmet research. Simultaneously, as a new type of magnetic material, it causes attention. Because Fe3S4 generally exists as an unstable intermediate, it is stringent in preparation conditions. Although some scholars have conducted on the synthesis experiments of Fe3S4 materials, the research on its stable conditions, formation mechanism and evolution process is not yet depth. Accordingly, defining the stable conditions and revealing evolution law of Fe3S4 nanocrystals have important significance for the determination of environmental conditions and the preparation of pure Fe3S4 nanomaterials. 展开更多
关键词 microscopIC OBSERVATION STABILITY Fe3S4 THERMAL and humid CONDITIONS
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Microscopic Theory of the Thermodynamic Properties of Sr_3Ru_2O_7
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作者 李伟正 吴从军 《Chinese Physics Letters》 SCIE CAS CSCD 2016年第3期86-90,共5页
The thermodynamic properties of the bilayer ruthenate compound Sr3Ru2O7 at very low temperatures are inves- tigated by using a tight-binding model yielding the realistic band structure combined with the on-site intera... The thermodynamic properties of the bilayer ruthenate compound Sr3Ru2O7 at very low temperatures are inves- tigated by using a tight-binding model yielding the realistic band structure combined with the on-site interactions treated at the mean-field level. We find that both the total density of states at the Fermi energy and the entropy exhibit a sudden increase near the critical magnetic field for the nematic phase, echoing the experimental find- ings. A new mechanism to explain the anisotropic transport properties is proposed based on scatterings at the anisotropic domain boundaries. Our results suggest that extra cares are necessary to isolate the contributions due to the quantum criticality from the band structure singularity in Sr3Ru2O7. 展开更多
关键词 in as on IT of RU microscopic Theory of the Thermodynamic Properties of Sr3Ru2O7 SR IS that
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ELECTRON MICROSCOPIC OBSERVATION OF SIMIAN SARCOMA VIRUS TRANSFORMED NIH 3T3 CELLS IN VITRO
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作者 田竟生 苏树芸 《Chinese Journal of Cancer Research》 SCIE CAS CSCD 1989年第2期16-18,共3页
For electronic microscopic observation, we found SSV-transformed NIH 3T3 cells were different from non-transformed cells. In SSV-transformed NIH 3T3 cells nuclei cytoplasma ratio was increased and in cytoplasma the ri... For electronic microscopic observation, we found SSV-transformed NIH 3T3 cells were different from non-transformed cells. In SSV-transformed NIH 3T3 cells nuclei cytoplasma ratio was increased and in cytoplasma the ribosomes (polyribosomes were attached to the swollen rough endoplasmic reticulum. It was likely that ribosomes were lined together functionally and structionally to produce specific protein (PDGF-like protein). 展开更多
关键词 NIH ELECTRON microscopIC OBSERVATION OF SIMIAN SARCOMA VIRUS TRANSFORMED NIH 3T3 CELLS IN VITRO RER
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Studies on mitochondrial macromolecular syntheses in various organs of aging animals labeled with 3H-precursors as revealed by electron microscopic radioautography
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作者 Tetsuji Nagata 《Advances in Bioscience and Biotechnology》 2010年第4期241-262,共22页
In order to study the aging changes of intramitochondrial macromolecular synthesis in various organs of aging animals during the development and aging, 10 groups of developing and aging mice, each consisting of 3 indi... In order to study the aging changes of intramitochondrial macromolecular synthesis in various organs of aging animals during the development and aging, 10 groups of developing and aging mice, each consisting of 3 individuals, total 30, from fetal day 19 to postnatal newborn at day 1, 3, 9, 14 and adult at month 1, 2, 6, 12 to 24 were injected with 3H-thymidine a DNA precurson, another 10 groups consisting of 3 individuals, total 30, were injected with 3H-uridine a RNA precursor, and another 10 groups of 30 individuals were injected with 3H-leucine a protein precursor, total 90 individuals. Then, all the animals were sacrificed 1 hr after the injections and the liver tissues, the lung tissues, the kidney tissues, the testis and ovary tissues, the adrenal tissues were taken out, fixed and processed for electron microscopic radioautography. On electron microscopic radioautograms obtained from each animal, ten photographs in respective groups, numbers of mitochondria per cell profile area, numbers of labeled mitochondria per cell and the mitochondrial labeling index (LI) labeled with 3H-thymidine showing DNA synthesis, LI labeled with 3H-uridine showing RNA synthesis, and LI labeled with 3H-leucine showing protein synthesis, in various organs, were counted and the results in various organs in respective aging groups were compared, respectively. From the results, it was demonstrated that the numbers of mitochondria in hepatocytes as well as in 3 zones of the adrenal cortex, the zona glomerulosa, fasciculata and reticularis of mice at various ages increased from fetal day 19 to postnatal month 1 due to development and aging of animals. On the other hand, the numbers of labeled mitochondria and the labeling indices of intramitochondrial DNA syntheses incorporating 3H-thymidine in hepatocytes and 3 zones of cortical cells increased from fetal day 19 to postnatal month 1 and decreased to month 24. The numbers of labeled mitochondria and the labeling indices of intramitochondrial RNA syntheses incorporating 3H-uridine in hepatocytes and 3 zones of cortical cells increased from fetal day 19 to postnatal month 1 and decreased to month 24. The numbers of labeled mitochondria and the labeling indices of intramitochondrial RNA syntheses incorporating 3H-uridine in hepatocytes and 3 ones of cortical cells increased from fetal day 19 to postnatal month 1 and decreased to month 24. Moreover, some other organs such as the lung and the testis were also review and discussed. From the results, it was shown that the activity of intramitochnodrial DNA synthesis, RNA synthesis, and protein synthesis in hepatocytes, adrenal cortical cells, pulmonary cells and testicular cells in developing and aging mice as well as some other organs increased and decreased due to development and aging. 展开更多
关键词 MITOCHONDRIAL Macromolecular SYNTHESES AGING ANIMALS Labeled 3H-Precursors ELECTRON microscopIC Radioautography
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CaCO_(3)晶须表面处理对改性沥青性能影响研究
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作者 邢向阳 张久鹏 +2 位作者 周庆月 张硕 陈文兵 《应用化工》 北大核心 2025年第4期976-982,共7页
CaCO_(3)晶须作为一种微米尺度的无机纤维状材料,能够对复合材料起到增强增韧作用。为研究CaCO_(3)晶须改性沥青的技术可行性,使用两种硅烷偶联剂KH-550和KH-570对CaCO_(3)晶须进行表面处理,采用多种微观试验方法表征了改性效果。在此... CaCO_(3)晶须作为一种微米尺度的无机纤维状材料,能够对复合材料起到增强增韧作用。为研究CaCO_(3)晶须改性沥青的技术可行性,使用两种硅烷偶联剂KH-550和KH-570对CaCO_(3)晶须进行表面处理,采用多种微观试验方法表征了改性效果。在此基础上制备CaCO_(3)晶须改性沥青,对经表面处理和未处理的CaCO_(3)晶须改性沥青的性能做了对比研究。结果显示:当KH550的用量为2.5%,KH570的用量为3.1%时,活化度最高,此时晶须表面改性效果最好;硅烷偶联剂可以提高晶须与沥青的黏附力;CaCO_(3)晶须的加入会使沥青的软化点提高,经硅烷偶联剂处理后晶须改性沥青效果更好;硅烷偶联剂表面改性工艺可以提高CaCO_(3)晶须改性沥青的储存稳定性。研究结果为CaCO_(3)晶须在沥青及沥青混合料中的应用提供参考。 展开更多
关键词 道路工程 CaCO_(3)晶须改性沥青 试验研究 微观表征 性能评价
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c面蓝宝石衬底上ε-Ga_(2)O_(3)的金属有机物化学气相沉积
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作者 王子铭 张雅超 +6 位作者 冯倩 刘仕腾 刘雨虹 王垚 王龙 张进成 郝跃 《人工晶体学报》 北大核心 2025年第3期420-425,共6页
本文采用金属有机物化学气相沉积(MOCVD)法在c面蓝宝石衬底上沉积ε-Ga_(2)O_(3)薄膜,研究了单步生长和两步生长方法对薄膜沉积的影响。采用单步法时,薄膜直接在蓝宝石衬底上生长,使用高分辨X射线单晶衍射分析沿蓝宝石c轴方向的Ga_(2)O_... 本文采用金属有机物化学气相沉积(MOCVD)法在c面蓝宝石衬底上沉积ε-Ga_(2)O_(3)薄膜,研究了单步生长和两步生长方法对薄膜沉积的影响。采用单步法时,薄膜直接在蓝宝石衬底上生长,使用高分辨X射线单晶衍射分析沿蓝宝石c轴方向的Ga_(2)O_(3)物相构成,在生长温度从360℃变化至425℃均能观察到β-Ga_(2)O_(3)(402)峰,而在370~410℃还能观察到ε-Ga_(2)O_(3)(004)峰。其中,380和390℃时的样品具有更强的ε-Ga_(2)O_(3)(004)峰和更低的半峰全宽,以及更低的表面粗糙度。两步生长法为以380℃生长的ε-Ga_(2)O_(3)薄膜作为缓冲层,而后在400~430℃继续生长ε-Ga_(2)O_(3)薄膜,观察到ε-Ga_(2)O_(3)(004)峰强度均高于单步生长法且半峰全宽均更低,在430℃时薄膜的(004)峰摇摆曲线半峰全宽达到0.49°。进一步改变单步生长法的压强,明确缓冲层有效促进ε-Ga_(2)O_(3)沿c轴生长。 展开更多
关键词 ε-Ga_(2)O_(3) 金属有机物化学气相沉积 蓝宝石衬底 晶体生长 宽禁带半导体 X射线衍射 原子力显微镜
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Al_(56)Pd_(17)Mn_(3)准晶拉伸性能的分子动力学模拟
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作者 熊浩然 田园 郭俊宏 《中国有色金属学报》 北大核心 2025年第11期3877-3887,共11页
通过选取合适的势函数,采用分子动力学方法,研究Al_(56)Pd_(17)Mn_(3)准晶在单轴拉伸条件下微观尺度的变形机制,分析裂纹长度、温度、应变速率对Al_(56)Pd_(17)Mn_(3)力学性能的影响规律。结果表明:裂纹的存在对Al_(56)Pd_(17)Mn_(3)的... 通过选取合适的势函数,采用分子动力学方法,研究Al_(56)Pd_(17)Mn_(3)准晶在单轴拉伸条件下微观尺度的变形机制,分析裂纹长度、温度、应变速率对Al_(56)Pd_(17)Mn_(3)力学性能的影响规律。结果表明:裂纹的存在对Al_(56)Pd_(17)Mn_(3)的力学性能有较大影响,裂纹缺陷区域附近原子的Mises应力明显低于其余区域原子的Mises应力,同时裂纹会阻碍变形所诱发的密排六方结构转变为其他结构的相变,且Al_(56)Pd_(17)Mn_(3)的弹性模量与抗拉强度随初始裂纹长度增加而减小,当裂纹长度由10?增加到50?时,弹性模量下降了38.76%,抗拉强度下降了40.3%;温度升高会降低Al_(56)Pd_(17)Mn_(3)的应力峰值和到达应力峰值时对应的应变量,且使其抗拉强度与弹性模量均降低,降低幅度分别为14%与8.36%;应变速率的减小会导致Al_(56)Pd_(17)Mn_(3)抗拉强度降低,但对其弹性模量的影响较小,即弹性模量仅减小1.5%。 展开更多
关键词 分子动力学 Al_(56)Pd_(17)Mn_(3) 拉伸 微观原子结构 纳米裂纹
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Si_(3)N_(4)/SiO_(2)核壳结构纳米线的滞弹性
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作者 文广玉 蔡丽景 +2 位作者 鲁佩佩 郑赫 王建波 《河北师范大学学报(自然科学版)》 2025年第2期115-120,共6页
相比于宏观材料,纳米材料的力学行为往往大有不同.使用原位电子显微学技术,在透射电镜中观察并探究了Si_(3)N_(4)/SiO_(2)核壳结构纳米线的力学行为.实验发现,Si_(3)N_(4)/SiO_(2)核壳结构纳米线具有明显的滞弹性,并且电子束辐照和应力... 相比于宏观材料,纳米材料的力学行为往往大有不同.使用原位电子显微学技术,在透射电镜中观察并探究了Si_(3)N_(4)/SiO_(2)核壳结构纳米线的力学行为.实验发现,Si_(3)N_(4)/SiO_(2)核壳结构纳米线具有明显的滞弹性,并且电子束辐照和应力加载速率都对纳米线后续的形状恢复过程有影响.讨论并解释了这一系列现象出现的原因,所得研究结果可以为纳米复合材料包括阻尼材料在内的潜在应用提供借鉴意义。 展开更多
关键词 透射电镜 Si_(3)N_(4)/SiO_(2)核壳结构纳米线 滞弹性
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Emergent 3×3 charge order on the Cs reconstruction of kagome superconductor CsV_(3)Sb_(5)
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作者 Xianghe Han Zhongyi Cao +4 位作者 Zihao Huang Zhen Zhao Haitao Yang Hui Chen Hong-Jun Gao 《Chinese Physics B》 2025年第1期46-51,共6页
The alkali adatoms with controlled coverage on the surface have been demonstrated to effectively tune the surface band of quantum materials through in situ electron doping.However,the interplay of orderly arranged alk... The alkali adatoms with controlled coverage on the surface have been demonstrated to effectively tune the surface band of quantum materials through in situ electron doping.However,the interplay of orderly arranged alkali adatoms with the surface states of quantum materials remains unexplored.Here,by using low-temperature scanning tunneling microscopy/spectroscopy(STM/S),we observed the emergent 3×3 super modulation of electronic states on the√3×√3R30°(R3)Cs ordered surface of kagome superconductor CsV_(3)Sb_(5).The nondispersive 3×3 superlattice at R3 ordered surface shows contrast inversion in positive and negative differential conductance maps,indicating a charge order origin.The 3×3 charge order is suppressed with increasing temperature and undetectable at a critical temperature of~62 K.Furthermore,in the Ta substituted sample CsV_(2.6)Ta_(0.4)Sb_(5),where long-range 2×2×2 charge density wave is significantly suppressed,the 3×3 charge order on the R3 ordered surface becomes blurred and much weaker than that in the undoped sample.It indicates that the 3×3 charge order on the R3 ordered surface is directly correlated to the bulk charge density waves in CsV_(3)Sb_(5).Our work provides a new platform for understanding and manipulating the cascade of charge orders in kagome superconductors. 展开更多
关键词 CsV_(3)Sb_(5) surface reconstruction alkali atoms charge order scanning tunneling microscope/spectroscopy
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Caspase-3参与调控蟾酥诱导人肺腺癌(ASTC-a-1)细胞的凋亡 被引量:11
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作者 陈同生 王小平 +2 位作者 孙磊 王会营 王龙祥 《生物化学与生物物理进展》 SCIE CAS CSCD 北大核心 2008年第1期85-90,共6页
采用基因质粒转染技术、荧光发射谱检测分析以及荧光共振能量转移(FRET)受体光漂白技术,首次在活细胞中实时检测中药蟾酥(Chan-Su,CS或bufonis venenum)诱导人肺腺癌(ASTC-a-1)细胞凋亡过程中caspase-3的活化特性.采用CCK-8(Cell Counei... 采用基因质粒转染技术、荧光发射谱检测分析以及荧光共振能量转移(FRET)受体光漂白技术,首次在活细胞中实时检测中药蟾酥(Chan-Su,CS或bufonis venenum)诱导人肺腺癌(ASTC-a-1)细胞凋亡过程中caspase-3的活化特性.采用CCK-8(Cell Couneing Kit-8)技术检测发现,蟾酥对细胞的活性具有显著的抑制作用;蟾酥处理稳定表达FRET质粒SCAT3的人肺腺癌细胞后,在不同的时间检测活细胞中SCAT3的荧光光谱;利用共聚焦扫描荧光显微成像技术检测蟾酥处理后细胞的形态,从而进一步证实蟾酥诱导细胞凋亡.实验结果表明:a.蟾酥可以有效抑制人肺腺癌(ASTC-a-1)细胞的增殖活性并诱导细胞的死亡.蟾酥对细胞的抑制作用具有剂量依赖性;b.蟾酥处理细胞6h后能检测到明显的细胞凋亡小体,连续作用24h后细胞全部皱褶,并有部分细胞破碎;c.蟾酥作用细胞2h就能明显切割细胞内的SCAT3,细胞内SCAT3的切割程度随着蟾酥作用时间的延长而增加,24h内细胞内的SCAT3完全被切割.受体光漂白实验也证实了该结论,表明caspase-3参与调控了蟾酥诱导的细胞凋亡过程. 展开更多
关键词 蟾酥 荧光光谱 caspae-3 荧光共振能量转移(FRET) 激光共聚焦荧光显微成像
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荧光探针Fluo-3/AM和FuraRed测量单细胞中比率钙 被引量:6
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作者 马晓冬 朱晓亮 +5 位作者 赵清 张瑾 张飒 雷国华 黄行许 鲍永耀 《中国医学物理学杂志》 CSCD 1999年第3期180-182,共3页
应用ACAS570激光扫描共聚焦显微镜(laserscanningconfocalmicroscope,LSCM简称共焦显微镜)和钙离子指示剂Fluo-3/AM、FuraRed荧光探剂双标记技术,测定了单个活细胞内比率钙的动态变化。结果显示37℃,Fluo-3/AM浓度10μmol/L,... 应用ACAS570激光扫描共聚焦显微镜(laserscanningconfocalmicroscope,LSCM简称共焦显微镜)和钙离子指示剂Fluo-3/AM、FuraRed荧光探剂双标记技术,测定了单个活细胞内比率钙的动态变化。结果显示37℃,Fluo-3/AM浓度10μmol/L,FuraRed浓度10μmol/L的条件下,昆明小鼠巨噬细胞负载1h左右即可获良好的标记效果。用比率探针测量细胞内Ca^2+的动态变化,使Ca^2+的定性定量测定不受染料浓度、细胞大小、照射光强度以及一定程度的光漂白和染料泄漏等因素的影响,提供了一种准确定性定量细胞内Ca^2+的实时、动态、原位变化的新方法。 展开更多
关键词 激光扫描 共聚焦显微镜 比率钙 荧光探针
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消癌平诱导人肺腺癌(ASTC-a-1)细胞内caspase-3活化的荧光光谱分析 被引量:12
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作者 陈同生 王小平 +3 位作者 王治平 王龙祥 王会营 邢达 《光谱学与光谱分析》 SCIE EI CAS CSCD 北大核心 2008年第6期1327-1331,共5页
采用CCK-8技术检测发现传统中药消癌平(XAP)对人肺腺癌(ASTC-a-1)细胞的增殖活性具有显著的抑制作用。利用共聚焦扫描荧光显微成像、荧光共振能量转移(FRET)及其受体光漂白技术证实了基于FRET技术构建的SCAT3质粒在ASTC-a-1细胞中的稳... 采用CCK-8技术检测发现传统中药消癌平(XAP)对人肺腺癌(ASTC-a-1)细胞的增殖活性具有显著的抑制作用。利用共聚焦扫描荧光显微成像、荧光共振能量转移(FRET)及其受体光漂白技术证实了基于FRET技术构建的SCAT3质粒在ASTC-a-1细胞中的稳定表达。将消癌平加入细胞培养液中培育细胞,并在不同的时间检测活细胞内SCAT3的荧光发射光谱,从而监测细胞中caspase-3的活化状态。实验结果表明:(1)消癌平可以有效抑制人肺腺癌(ASTC-a-1)细胞的增殖活性并诱导细胞的死亡,消癌平对细胞的抑制作用具有剂量依赖性。(2)消癌平处理细胞72 h后,细胞内大量的SCAT3被切割,表明细胞内caspase-3的活化水平明显升高。(3)将含消癌平的细胞培养液与细胞共同培养24 h,然后采用没有消癌平的细胞培养液培养细胞48和72 h后,细胞内SCAT3的光谱没有明显改变,表明消癌平作用细胞24 h内没有显著激活细胞内的caspase-3。 展开更多
关键词 消癌平 荧光光谱 caspae-3 荧光共振能量转移(FRET) 激光共聚焦荧光显微镜
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紫杉醇诱导不依赖于Caspase-3细胞类似Paraptosis的荧光光谱分析 被引量:6
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作者 陈同生 王小平 +2 位作者 孙磊 王会营 王龙祥 《光谱学与光谱分析》 SCIE EI CAS CSCD 北大核心 2008年第11期2623-2627,共5页
研究了紫杉醇(Taxol)诱导人肺腺癌细胞(ASTC-a-1)类似Paraptosis的特征和机理。采用CCK-8技术检测了抑制细胞活性的特性,结果表明大于70μmol.L-1浓度的紫杉醇可以显著抑制细胞活性;采用激光共聚焦扫描荧光成像从形态上检测了紫杉醇诱... 研究了紫杉醇(Taxol)诱导人肺腺癌细胞(ASTC-a-1)类似Paraptosis的特征和机理。采用CCK-8技术检测了抑制细胞活性的特性,结果表明大于70μmol.L-1浓度的紫杉醇可以显著抑制细胞活性;采用激光共聚焦扫描荧光成像从形态上检测了紫杉醇诱导细胞死亡的形态特征,表明紫杉醇诱导了类似副凋亡(Paraptosis)特征的细胞肿胀和细胞质空泡化,而且没有细胞膜皱褶、细胞核浓缩等细胞凋亡的特征;通过基因质粒转染在细胞转染稳定表达基于荧光共振能量转移(FRET)质粒SCAT3,并利用FRET受体光漂白技术和荧光光谱检测分析技术研究了紫杉醇诱导细胞类似Paraptosis过程中Caspase-3的活化特性,结果表明在紫杉醇诱导细胞质肿胀和细胞死亡的过程中Caspase-3没有被活化。以上研究结果表明紫杉醇可以通过类似Paraptosis的方式明显诱导细胞程序性死亡,该过程不依赖于Caspase-3的活性。 展开更多
关键词 紫杉醇(Taxol) Paraptosis 荧光光谱 Caspae-3 荧光共振能量转移(FRET) 激光共聚焦荧光显微镜
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交变磁场对换热壁面CaCO_(3)污垢的阻垢特性实验研究 被引量:7
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作者 梁延东 徐源 +1 位作者 徐雪霏 王建国 《中国电机工程学报》 EI CSCD 北大核心 2022年第21期7913-7921,共9页
通过分析污垢热阻、电导率和pH这3个参数的变化,并结合CaCO_(3)污垢扫描电镜图片,探究不同磁感应强度(0、100、200、300和400Gs)下交变磁场对换热壁面CaCO_(3)污垢的阻垢特性。实验结果表明:交变磁场通过对水溶液和CaCO_(3)的结晶过程... 通过分析污垢热阻、电导率和pH这3个参数的变化,并结合CaCO_(3)污垢扫描电镜图片,探究不同磁感应强度(0、100、200、300和400Gs)下交变磁场对换热壁面CaCO_(3)污垢的阻垢特性。实验结果表明:交变磁场通过对水溶液和CaCO_(3)的结晶过程产生影响,可以有效降低CaCO_(3)污垢在换热壁面的沉积速度,减小污垢热阻;交变磁场能够降低溶液的电导率和pH,促进CaCO_(3)的均相成核,增加溶液中的总沉淀量;交变磁场阻碍Ca CO_(3)晶型中文石向方解石的转变,促使文石的比例和尺寸增加。同时,交变磁场的阻垢特性存在极值特征,文中实验工况下,300Gs时交变磁场呈现最佳阻垢效果,阻垢率为78.2%。相比空白实验组,溶液的电导率和pH分别下降了7.5%和0.28;文石的比例和尺寸显著增加。 展开更多
关键词 交变磁场 CaCO_(3) 污垢热阻 电导率 pH 扫描电镜
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