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Thermal conductivity characterization of ultra-thin silicon film using the ultra-fast transient hot strip method

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Chinese Physics B 2019年第7期28卷 499-503页

作者： Yan-Yan Zhang Ran Cheng Dong Ni Ming Tian Ji-Wu Lu Yi Zhao College of Information Science and Electronic Engineering Zhejiang University Hangzhou 310027 China State Key Laboratory of Industrial Control Technology Zhejiang University Hangzhou 310027 China Shanghai Huali Microelectronics Corporation Shanghai 200120 China College of Electrical and Information Engineering Hunan University Changsha 410082 China

Thermal conductivity is an important material parameter of silicon when studying the performance and reliability of devices or for guiding circuit design when considering heat dissipation, especially when the self-heating effect becomes prominent in ultra-scaled *** cross-plane thermal conductivity of a thin silicon film is lacking due to the difficulty in sensing high thermal conductivity in the vertical *** this paper, a feasible method that utilizes an ultra-fast electrical pulse within 20 μs combined with the hot strip technique is *** the best of our knowledge, this is the first work that shows how to extract the cross-plane thermal conductivity of sub-50 nm(30 nm, 17 nm, and 10 nm)silicon films on buried *** ratio of the extracted cross-plane thermal conductivity of the silicon films over the bulk value is only about 6.9%, 4.3%, and 3.8% at 300 K, *** the thickness of the films is smaller than the phonon mean free path, the classical heat transport theory fails to predict the heat dissipation in nanoscale ***, in this study, a ballistic model, derived from the heat transport equation based on extended-irreversible-hydrodynamics(EIT), is used for further investigation, and the simulation results exhibit good consistence with the experimental *** extracted effective thermal data could provide a good reference for precise device simulations and thermoelectric applications.

关键词： cross-plane thermal conductivity ultra-fast transient hot strip method

Fabrication and Characterization of High-Voltage ultra-fast GaAs Photoconductive Switch

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Journal of Semiconductors 1998年第6期 38-42页

作者： Shi Wei 1, Liang Zhenxian 2, Xu Chuanxiang 2(1 Applied Physics Department, Xi’an University of Technology, Xi’an 710048) (2 Institute of Electrical Insulation, Xi’an Jiaotong University, Xi’an 710049)

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关键词： GaAs Photoconductive ultra-fast High-Voltage Switch and Fabrication Characterization

固相萃取-超快速液相色谱-串联质谱法同时测定血液中的4种苏丹染料

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色谱 2014年第3期32卷 224-229页

作者：朱浩黄坤玉付建飞胡岳黄娴妮陈晓红邹宝波金米聪宁波大学医学院浙江宁波315211 宁波市疾病预防控制中心浙江省微量有毒化学物健康风险评估技术研究重点实验室浙江宁波315010 宁波市疾病预防控制中心宁波市毒物研究与控制重点实验室浙江宁波315010

建立了血液样品中4种苏丹染料（苏丹Ⅰ、Ⅱ、Ⅲ和Ⅳ）的固相萃取-超快速液相色谱-串联质谱（ UFLC-MS /MS）测定方法。样品经乙腈涡旋振荡提取，上清液加等体积水稀释混匀后移入 C18固相萃取小柱净化，采用 Agi-lent Eclipse Plus C18... 详细信息

建立了血液样品中4种苏丹染料（苏丹Ⅰ、Ⅱ、Ⅲ和Ⅳ）的固相萃取-超快速液相色谱-串联质谱（ UFLC-MS /MS）测定方法。样品经乙腈涡旋振荡提取，上清液加等体积水稀释混匀后移入 C18固相萃取小柱净化，采用 Agi-lent Eclipse Plus C18色谱柱（100 mm×2.1 mm，1.8μm）以0.1％（v / v）甲酸水溶液和0.1％（v / v）甲酸乙腈溶液为流动相梯度洗脱分离，电喷雾电离（ESI）正离子多反应监测模式进行定量分析。讨论了苏丹Ⅲ和苏丹Ⅳ的偶氮基团 E-Z 光学异构现象，并对影响因素进行了分析。结果4种苏丹染料在0.1～20.0μg / L 范围内线性关系良好，相关系数均大于0.999；在低、中、高3个加标水平的平均回收率为93.0％～108.2％，相对标准偏差为4.8％～9.5％；方法的检出限（LOD）为0.06μg / L，定量限（LOQ）为0.2μg / L。本方法准确、快速、灵敏，可用于血液样品中苏丹类染料的检测分析。

关键词：超快速液相色谱-串联质谱法固相萃取苏丹染料血液 ultra-fast liquid chromatography-tandem mass spectrometry(UFLC-MS MS) sol-id-phase extraction(SPE)

Electrical transport and optical properties of Cd3As2 thin films

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Chinese Physics B 2019年第10期28卷 93-100页

作者： Yun-Kun Yang Fa-Xian Xiu Feng-Qiu Wang Jun Wang Yi Shi Collaborative Innovation Center of Advanced Microstructures Nanjing 210093China State Key Laboratory of Surface Physics and Department of Physics Fudan UniversityShanghai 200433China School of Electronic Science and Engineering Nanjing UniversityNanjing 210093China School of Optoelectronic Science and Engineering University of Electronic Science and Technology of ChinaChengdu 610054China State Key Laboratory of Electronic Thin Films and Integrated Devices University of Electronic Science and Technology of ChinaChengdu 610054China National Laboratory of Solid State Microstructures School of PhysicsNanjing UniversityNanjing 210093China

Cd3As2, as a three-dimensional(3D) topological Dirac semimetal, has attracted wide attention due to its unique physical properties originating from the 3D massless Dirac fermions. While many efforts have been devoted to the exploration of novel physical phenomena such as chiral anomaly and phase transitions by using bulk crystals, the development of high-quality and large-scale thin films becomes necessary for practical electronic and optical applications. Here, we report our recent progress in developing single-crystalline thin films with improved quality and their optical devices including Cd3As2-based heterojunctions and ultrafast optical switches. We find that a post-annealing process can significantly enhance the crystallinity of Cd3As2 in both intrinsic and Zn-doped thin films. With excellent characteristics of high mobility and linear band dispersion, Cd3As2 exhibits a good optical response in the visible-to-mid-infrared range due to an advantageous optical absorption, which is reminiscent of 3D graphene. It also behaves as an excellent saturable absorber in the mid-infrared regime. Through the delicate doping process in this material system, it may further open up the long-sought parameter space crucial for the development of compact and high-performance mid-infrared ultrafast sources.

关键词： topological Dirac semimetals thin films photodetectors ultra-fast optical switches

β-Phase Crystallization of Poly(vinylidene fluoride) in Poly(vinylidene fluoride)/Poly(ethyl methacrylate) Blends

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Chinese Journal of Polymer Science 2019年第1期37卷 94-100,4-7页

作者： Zi-Jie Huang Jing Jiang Gi Xue Dong-Shan Zhou Department of Polymer Science and Engineering School of Chemistry and Chemical Engineering Key Laboratory of High Performance Polymer Materials and Technology and The State Key Laboratory of Coordination Chemistry Nanjing University School of Physical Science and Technology Xinjiang Key Laboratory and Phase Transitions and Microstructures in Condensed Matters Yili Normal University

The nature of the crystalline phase of poly(vinylidene fluoride)(PVDF) in compatible blends with poly(ethyl methacrylate)(PEMA) was investigated by using X-ray diffraction(XRD), infrared microscopy(IR) and differential scanning calorimetry(DSC). The βphase of PVDF was observed after quenching from the melt and further annealing above the glass transition temperature over a composition range. The PVDF/PEMA blend with weight ratio of 3:2 has formed higher content of PVDF β crystals than others. By taking advantage of fast cooling rate of ultrafast differential scanning calorimeter(UFDSC), the quenching process of blends was modeled and tested simultaneously, and the melting behavior of β crystals in all blends was investigated. Three types of crystallization behavior of βphase PVDF in blends were found after quenching-annealing at different temperatures.

关键词： β-Crystal of PVDF Mesophase PVDF/PEMA blend ultra-fast scanning calorimetry

A simulation study of Tsinghua Thomson scattering X-ray source

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Chinese Physics C 2009年第S2期33卷 146-150页

作者：唐传祥李任恺黄文会陈怀璧杜应超杜强杜泰斌何小中林郁正钱厚俊施嘉儒向导颜立新余沛成 Department of Engineering Physics Tsinghua University Key Laboratory of Particle & Radiation Imaging (Tsinghua University) Ministry of Education ey Laboratory of High Energy Radiation Imaging Fundamental Science for National Defense

Thomson scattering X-ray sources are compact and a?ordable facilities that produce short duration, high brightness X-ray pulses enabling new experimental capacities in ultra-fast science studies, and also medical and industrial applications. Such a facility has been built at the Accelerator Laboratory of Tsinghua University, and upgrade is in progress. In this paper, we present a proposed layout of the upgrade with design parameters by simulation, aiming at high X-ray pulses flux and brightness, and also enabling advanced dynamics studies and applications of the electron beam. Design and construction status of main subsystems are also presented.

关键词： Thomson scattering X-ray ultra-fast brightness

Photoinduced intramolecular charge transfer of sodium 4-(N,N-dimethylamino)benzenesulfonate

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Science China Chemistry 2000年第3期43卷 295-305页

作者：林丽榕江云宝 Department of Chemistry and the MOE Key Laboratory of Analytical Sciences Xiamen University Xiamen 361005China

A new dual fluorescent N,N-dimethylaniline derivative, sodium 4-(N,N-dimethylamino)-benzenesulfonate (SDMAS), is reported. In SDMAS, the electron acceptor is linked to the phenyl ring via a sulfur atom at the para-position of the electron donor. It was found that SDMAS emits dual fluorescence only in highly polar solvent water but not in organic solvents such as formamide, methanol and acetonitrile. In organic solvents only a single-band emission atca.360 nm was observed in the short wavelength region. The dual fluorescence of SDMAS in water was found at 365 and 475 nm, respectively. Introduction of organic solvent such as ethanol, acetonitrile, and 1,4-dioxane into aqueous solution of SDMAS leads to blue-shift and quenching of the long-wavelength emission. Measurements of steady-state and picosecond time-resolved fluorescence indicate that the long wavelength fluorescence is emitted from a charge transfer (CT) state that is populated from the locally excited (LE) state, with the latter giving off the short wavelength fluorescence. The fact that a highly polar solvent is required to bring out the dual fluorescence suggests that the CT process of SDMAS has a high activation energy (E a). In supporting this assumption the timeresolved fluorescence measurements give anE a of 15.35 kJ·mol-1. It was assumed that the participation of the sulfur atom d-orbital in the conjugation of sulfonate group with phenyl ring and the strong twisting and inverting of the dimethylamino plane relative to the phenyl ring could be the reasons for the high activation energy. A molecular configuration change upon charge transfer in water was suggested for SDMAS based on the thermodynamic data. SDMAS reported here represents the example of the dual fluorescent amine substituted aromatic sulfonate.

关键词： intramolecular charge transfer dual fluorescence picosecond time-resolved fluorescence ultra-fast kinetics excited-state structural relaxation sodium 4-(N N-dimethylamino)benzenesulfonate.

A Low-Memory-Requiring and fast Approach to Cluster Large-Scale Decoy Protein Structures

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Open Journal of Biophysics 2012年第3期2卷 57-63页

作者： Yate-Ching Yuan Yingzi Shang Hongzhi Li Department of Molecular Medicine City of Hope National Medical Center and Beckman Research InstituteDuarte USA he School of Mathematics and Statistics Hebei University of Economics and Business Shijiazhuang China

This work demonstrates the so-called PCAC (Protein principal Component Analysis Clustering) method, which clusters large-scale decoy protein structures in protein structure prediction based on principal component analysis (PCA), is an ultra-fast and low-memory-requiring clustering method. It can be two orders of magnitude faster than the commonlyused pairwise rmsd-clustering (pRMSD) when enormous of decoys are involved. Instead of N(N – 1)/2 least-square fitting of rmsd calculations and N2 memory units to store the pairwise rmsd values in pRMSD, PCAC only requires N rmsd calculations and N × P memory storage, where N is the number of structures to be clustered and P is the number of preserved eigenvectors. Furthermore, PCAC based on the covariance Cartesian matrix generates essentially the identical result as that from the reference rmsd-clustering (rRMSD). From a test of 41 protein decoy sets, when the eigenvectors that contribute a total of 90% eigenvalues are preserved, PCAC method reproduces the results of near-native selections from rRMSD.

关键词： Protein Structure Predicition Protein Structure Cluster Principal Component Analysis Low-Momery-Requiring Clustering ultra-fast Clustering

Subcellular Cysteine ultrafast Lighting

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Subcellular Cysteine Ultrafast Lighting