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Conformation Analysis and Comparison of Epristeride(17β-N-t-Butylcarboxamide-androst-3,5-diene-3-carboxylic Acid) and Its Analogs

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Chemical Research in Chinese Universities 2005年第5期21卷 525-527页

作者： yao li-xin Lab of Molecular Drug Design Key Laboratory of Controlled Release of Guangdong ProvinceInstitute of Materia Medica Guangdong College of Pharmacy Guangzhou 510240 P. R. China

Conformations of Epristeride（ 17-β-N-t-butylcarboxamide-androst-3,5-diene-3-carboxylic acid） and its analogs were analyzed with the random search method and compared by means of the methods for steroid conformers, Connolly surfaces, dihedral angles, and molecular accessibility probes with protons, hydroxyl and methyl groups contained simultaneously. Analog d is different from others, which is in accordance with the preliminary clinical trial results under double blind conditions.

关键词： Epristeride Conformation analysis Molecular accessibility Analog

A Bombieri-type Theorem for Exponential Sums

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Acta Mathematica Sinica,English Series 2013年第10期29卷 1997-2012页

作者： Wei li yao Department of Mathematics College of SciencesShanghai University School of Mathematics Shandong University

Let fk（n） be the characteristic function of n with Ω（n） = k, and T k（x,α）=∑n≤xfk（n）e（nα）.The main purpose of this paper is to establish a Bombieri-type mean-value theorem for Tk（x, α）, via using the modified Huxley-Hooley contour and the large-sieve type zero-density estimate for Dirichlet L-functions. The result plays an important role in handling the enlarge major arcs when we try to solve the Waring-Goldbach type problem by the circle method

关键词： Zero-density estimate Huxley-Hooley contour .Bombieri-type theorem

Semirigid vibrating rotor target model for atom- polyatom reactions: Application to F+CH_(4)→ CH_(3)+HF

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Chinese Science Bulletin 2006年第7期51卷 802-808页

作者： yao li Department of Physics Dalian Maritime University Dalian 116023 China

The semirigid vibrating rotor target (SVRT) model for the polyatomic reaction has been applied to the reaction of F+CH4→HF+CH3. The time-dependent wave packet approach has also been used in the calculation. In the current study, reaction probability, cross-section, and rate constant are calculated for the title reaction on the modified J1 (MJ1) potential energy surface (PES). Numerical calculation shows oscillatory structures in the energy dependence of the calculated reaction probability. Those structures are generally associated with broad dynamical resonance. They are almost washed-out in the energy dependence of integral cross-sections due to summation over partial waves. The calculated rate constant is in good agreement with experimental measurement.

关键词： SVRT TDWP 反应概率截面速度常数 CH4 CH3 势能表面

One stone two birds:Dual-effect kinetic regulation strategy for practical lithium–sulfur batteries

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Journal of Energy Chemistry 2022年第2期31卷 302-303页

作者： Xi-yao li Qiang Zhang Beijing Key Laboratory of Green Chemical Reaction Engineering and Technology Department of Chemical EngineeringTsinghua UniversityBeijing 100084China

lithium–sulfur(li–S)batteries are deemed as one of the most promising energy storage systems due to their ultrahigh theoretical energy density of 2600 Wh kg^(-1) far beyond the current lithium-ion battery technique[1].

关键词： battery lithium Dual

Local scour by multiple slit-type energy dissipaters

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Journal of Hydrodynamics 2020年第6期32卷 1221-1224页

作者： li yao Jian-hua Wu College of Water Conservancy and Ecological Engineering Nanchang Institute of TechnologyNanchang330099China College of Water Conservancy and Hydropower Engineering Hohai UniversityNanjing210098China

Energy dissipation and scour control are all the key issues for the design of hydraulic *** the basis of the high energy dissipation for the multiple slit-type energy dissipaters(M-STED)developed by the authors,in this work,the characteristics of the scour hole for the M-STED were experimentally investigated through three sets of those physical models with five cases and a scour hole form index was *** results show that,the M-STED results in not only the high energy dissipation but also the mild upstream slope of the scour hole thanks to the scour hole form index of larger than 0.5,which is in favor of the safety of the release works.

关键词： Energy dissipation scour scour hole form index multiple slit-type energy dissipater

Optomechanical force gradient sensing with levitated nanosphere pair

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Science China(Physics,Mechanics & Astronomy) 2022年第4期65卷 32-40页

作者： Chuang li yao li Huizhu Hu Ying Dong Research Center for Quantum Sensing Zhejiang LaboratoryHangzhou 311100China State Key Laboratory of Modern Optical Instrumentation&College of Optical Science and Engineering Zhejiang UniversityHangzhou 310027China

Guided by recent progress in ground state cooling and ultraweak force sensing in the optomechanical systems with optically levitated particles,we propose a novel quantum sensing protocol that can detect the gradient of a force field directly with extremely high *** system consists of a pair of nanospheres levitated in the high vacuum environment with optical tweezers and an optical *** positioning the two spheres suitably relative to the cavity,only the collective breathing mode of the sphere pair couples to the cavity *** optomechanical coupling will transfer the information of force difference acting on the two sensors to cavity photons,which can then be detected directly at the output of the *** the optimal control of various technical noise sources,the sensitivity could reach 10^(-15)N m^(-1)/√HZ with a high spatial resolution of micron scale on a state-of-the-art experimental *** potential application of this protocol in searching for short range“new force”is *** with conventional searching protocols with a single levitated sphere,the method proposed here can increase the signal-to-noise ratio by more than one magnitude in a large searching parameter space.

关键词： optomechanics optical tweezers force gradient quantum sensing

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Preparation and thermal stability of Pd_(40.5)Ni_(40.5)Si_xP_(19-x) bulk metallic glasses

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International Journal of Minerals,Metallurgy and Materials 2010年第2期17卷 204-207页

作者： Yang li yao-cen Wang Ke-fu yao Department of Mechanical Engineering Tsinghua University Beijing 100084 China

With the addition of Si to replace some P,Pd40.5Ni40.5SixP19-x（x=0,2.5,5,9.5,14,and 19 in atomic number fraction） bulk glassy samples with the diameter of about 5 mm were successfully prepared by use of flux treatment and water quenching *** the increase of Si content,the glass forming ability of Pd40.5Ni40.5Si-xP19-x increases first for low Si content and then decreases for high Si content （Si≥9.5at%）.The Pd40.50Ni40.5Si5P14 glassy alloy possesses the largest supercooled liquid region△T of 119 K,the largest reduced glass transition temperature of 0.621,and the largestγparameter of 0.460,indicating that this glassy alloy possesses very large glass forming ability and very high thermal stability.

关键词： bulk metallic glass flux method glass forming ability water quenching thermal stability

基于纳秒liBS的氢气/空气火焰混合分数测量研究

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光谱学与光谱分析 2025年第1期45卷 24-29页

作者：刘子晗刘艳韩磊单沅鲁政高强李帅瑶李博天津大学内燃机燃烧学国家重点实验室天津300072 中国科学院工程热物理研究所北京100190

在双碳政策和化石能源短缺的背景下,氢能作为高效环保的清洁能源,受到广大研究人员的关注。氢气/空气混合燃烧作为推动氢能规模化应用的重要途径,其燃烧机理和关键参数的测量技术成为目前研究的热点。燃空当量比是表征燃烧过程中燃料与... 详细信息

在双碳政策和化石能源短缺的背景下,氢能作为高效环保的清洁能源,受到广大研究人员的关注。氢气/空气混合燃烧作为推动氢能规模化应用的重要途径,其燃烧机理和关键参数的测量技术成为目前研究的热点。燃空当量比是表征燃烧过程中燃料与氧化剂混合程度的重要参数,直接影响燃烧的开始、自持以及燃烧化学反应的活跃程度。因此,对燃烧过程中的局部当量比实时在线监测,对于改善燃烧效率、控制燃烧过程具有重要意义。目前,可以实时测量氢气/空气火焰当量比的方法相对较少,激光光谱技术作为一种非侵入式的测量方法,不仅具有实时在线测量的能力,还具有快速、原位、远程分析、多元素同时在线监测等特点,在燃烧测量领域具有重要的应用潜力。采用纳秒激光诱导击穿光谱技术对氢气和空气燃烧场的燃空当量比进行测量研究。氢气和空气在管内混合后,由射流口喷出形成射流燃烧火焰场。激光通过透镜聚焦到射流燃烧场中击穿并产生等离子体,其等离子体的发射光谱由光谱仪采集,实验发现光谱中H 656 nm和O 777 nm具有很强的发射强度,且光谱强度随着当量比的变化,呈现规律性变化趋势。因此,采用H 656 nm和O 777 nm的光谱分别标示氢气和空气,并将其比值作为燃空当量比的测量参量。实验在氢气空气混合均匀的低速流场中测量了不同当量比下H 656 nm与O 777 nm的光谱强度比值,并与当量比建立标定曲线,实验发现该标定曲线对燃烧场和非燃烧场同样适用。基于标定曲线,我们研究了存在外界掺混情况下,射流燃烧场的局部燃空当量比情况。在当量比1.0,流场速度为20 m·s^(-1)的射流燃烧场中,测量了射流中心位置不同高度的燃空当量比变化情况,并在相同工况下进行了数值模拟。模拟结果与实验测量吻合较好,验证了纳秒激光诱导击穿光谱技术测量氢气/空气混合气的燃空当量比的可行性。该方法可为氢气燃烧基础研究及数值模拟提供技术支持。

关键词：激光诱导击穿光谱氢能当量比模拟

Photoelectron Spectroscopy, Photoionization Mass Spectroscopy, and Theoretical Study on CCl3SSCN

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Chinese Journal of Chemical Physics 2008年第2期21卷 93-98页

作者： lin Du li yao Mao-fa Ge Beijing National Laboratory for Molecular Sciences State Key Laboratory for Structural Chemistry of Unstable and Stable Species Institute of Chemistry Chinese Academy of Sciences Beijing 100080 China Graduate School of Chinese Academy of Sciences Beijing 100039 China

Trichloromethanesulfenyl thiocyanate, CCl3SSCN, was generated and studied by photoelectron spectroscopy （PES）, photoionization mass spectroscopy （PIMS）, and theoretical calculations. This molecule exhibits a gauche conformation, and the torsional angle around S-S bond is 91.4° due to the sulfur-sulfur lone pair interactions. After ionization, the ground-state cationic-radical form of CCl3SSCN＋ adopts a trans planar main-atom structure with Cs symmetry. The highest occupied molecular orbital （HOMO） of CC13SSCN corresponds to the electrons mainly localized on the sulfur 3p lone pair MO. The first ionization energy is determined to be 10.40 cV.

关键词： Photoelectron spectroscopy Photoionization mass spectroscopy Electronic structure