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Chinese Physics Letters 2020年第3期37卷 73-77页

作者： Bin Wang hao-Yu Kong lei Sun Institute of Microelectronics Peking UniversityBeijing 100871

A dual silicide layer structure is proposed for Schottky barrier metal-oxide-semiconductor held effect transistors(MOSFETs)on bulk *** source/drain regions are designed to be composed with dual stacked silicide layers,forming different barrier heights to silicon *** comparisons between the dual barrier structure and the single barrier structure are carried out with numerical *** is found that the dual barrier structure has significant advantages over the single barrier structure because the drive current and leakage current of the dual barrier structure can be ***,the dual barrier structure's performance is nearly insensitive to the total silicide thickness,which can relax the fabrication requirements and even make an SOI substrate unnecessary for planar device *** formation of ErSix/CoSi2 stacked multilayers has been proved by experiments.

关键词： Schottky MOSFETs drain

Laser-Induced Electron Fresnel Diffraction in Tunneling and Over-Barrier Ionization

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Chinese Physics Letters 2022年第4期39卷 17-21页

作者： lei Geng hao Liang Liang-You Peng State Key Laboratory for Mesoscopic Physics and Frontiers science Center for Nano-optoelectronics School of PhysicsPeking UniversityBeijing 100871China Collaborative Innovation Center of Quantum Matter Beijing 100871China Collaborative Innovation Center of Extreme Optics Shanxi UniversityTaiyuan 030006China beijing Academy of Quantum Information sciences Beijing 100193China

Photoelectron momentum distribution in strong-field ionization has a variety of structures that reveal the complicated dynamics of this ***,we identified a low-energy interference structure in the case of a super-intense extreme ultraviolet(XUV)laser pulse and attributed it to the laser-induced electron Fresnel *** structure is determined by the laser-induced electron displacement[Geng et ***.A104(2021)L021102].In the present work,we find that the Fresnel diffraction picture also appears in the tunneling and over-barrier regime of ionization by short ***,the electron displacement is now induced by the electric field component of the laser pulse rather than the magnetic field component in the case of the super-intense XUV *** corresponding modifications to our quantum and semiclassical models,we find that the same physical mechanism of the Fresnel diffraction governs the low-energy interference structures along the laser *** results predicted by the two models agree well with the accurate results from the numerical solution to the time-dependent Schr¨odinger equation.

关键词： equation process Fresnel

Lattice-based certificateless encryption scheme

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Frontiers of Computer science 2014年第5期8卷 828-836页

作者： Mingming JIANG Yupu HU hao lei Baocang WANG Qiqi LAI State Key Laboratory of Integrated Service Networks Xidian University Xi'an 710071 China Security and Privacy Lab CRDU Huawei Technologies Co. LTD. Beijing 100095 China

Certificateless public key cryptography （CL- PKC） can solve the problems of certificate management in a public key infrastructure （PKI） and of key escrows in identity-based public key cryptography （ID-PKC）. In CL- PKC, the key generation center （KGC） does not know the private keys of all users, and their public keys need not be cer- tificated by certification authority （CA）. At present, however, most certificateless encryption schemes are based on large in- teger factorization and discrete logarithms that are not secure in a quantum environment and the computation complexity is high. To solve these problems, we propose a new certificate- less encryption scheme based on lattices, more precisely, us- ing the hardness of the learning with errors （LWE） problem. Compared with schemes based on large integer factoriza- tion and discrete logarithms, the most operations are matrix- vector multiplication and inner products in our scheme, our approach has lower computation complexity. Our scheme can be proven to be indistinguishability chosen ciphertext attacks （IND-CPA） secure in the random oracle model.

关键词： lattice-based cryptography LWE identity-based encryption (IBE) post-quantum cryptography certifi-cateless encryption

Global Fujita-Kato's Type Solutions and Long-time Behavior for the Multidimensional Chemotaxis Model

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Acta Mathematica Sinica,English Series 2022年第2期38卷 311-330页

作者： Qiong lei CHEN Xiao Nan hao Jing Yue LI Institute of Applied Physics and Computational Mathematics Beijing 100088P.R.China School of Mathematical sciences Peking UniversityBeijing 100871P.R.China

We establish the global well-posedness for the multidimensional chemotaxis model with some classes of large initial data,especially the case when the rate of variation of ln v0(v0 is the chemical concentration)contains high oscillation and the initial density near the equilibrium is allowed to have large oscillation in ***,we show the optimal time-decay rates of the strong solutions under an additional perturbation assumption,which include specially the situations of d=2,3.and improve the previous time-decay *** method mainly relies on the introduce of the effective velocity and the application of the localization in Fourier spaces.

关键词： Critical Besov spaces chemotaxis model global well-posedness optimal time-decay rates

Understanding microstructure-evolution-dependent fracture behaviors in pearlitic steels

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Journal of Iron and Steel Research International 2020年第3期27卷 334-341页

作者： Hu Chen Chi Zhang hao Chen Zhi-gang Yang lei Chen Key Laboratory of Advanced Materials of Ministry of Education School of Materials Science and EngineeringTsinghua UniversityBeijing 100084China Department of Mechanical engineering Mississippi State UniversityStarkvilleMS 39762USA

Microstructure evolution or degradation has been well recognized to be closely related to the formation of microcracks in pearlitic rails and *** rolling contact fatigue machine was employed to simulate the rail-wheel contact,and the microstructure evolution and crack formation of pearlitic steels subjected to rolling-sliding contact loading were then experimentally *** further quantitatively predict the fracture behaviors,a phase-field model was herein established to investigate the cyclic loading-driven microstructure evolution and the microstructure-dependent fracture resistance in *** coupling of microstructure evolution and crack propagation was realized through the introduction of two-set order parameters,i.e.,the crack field and the microstructure field,and the microstructure-dependent fracture *** proposed model can predict the fracture resistance of microstructure at different depths from the contact surface,after different rolling cycles and with different initial pearlitic microstructures,which can shed light on the design of damage-resistant microstructure of pearlitic steels.

关键词： Pearlitic steel Rolling-sliding contact Microstructure evolution Crack propagation Phase-field model

钢框架岩棉夹芯板超高防火隔墙耐火与稳定性能研究

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消防科学与技术 2024年第8期43卷 1105-1110页

作者：郝腾飞赵东拂李磊王长辉符演北京建筑大学土木与交通工程学院北京100044 中国建筑科学研究院有限公司北京100013 北京未来城市设计高精尖创新中心北京100044 北京建筑大学大型多功能振动台阵实验室北京100044 北京建筑大学北京节能减排与城乡可持续发展省部共建协同创新中心北京100044 工程结构与新材料北京市高等学校工程研究中心北京100044

为满足大型厂房对轻质超高防火隔墙的需求,提出了一种钢框架岩棉夹芯板超高防火隔墙,并对其耐火性与稳定性进行研究。采用ISO-83.标准升温曲线的加热方法,对缩尺比例为1∶0.3.棉夹芯板防火隔墙进行单面受火试验。并基于有限元软件ABAQU... 详细信息

为满足大型厂房对轻质超高防火隔墙的需求,提出了一种钢框架岩棉夹芯板超高防火隔墙,并对其耐火性与稳定性进行研究。采用ISO-83.标准升温曲线的加热方法,对缩尺比例为1∶0.3.棉夹芯板防火隔墙进行单面受火试验。并基于有限元软件ABAQUS建立缩尺模型与足尺模型,研究了防火隔墙防火优化前后两种方案下受火面与背火面的温度场变化规律。结果表明:缩尺试验模型与缩尺有限元模型的温度和形变基本吻合;足尺有限元模型的岩棉夹芯板超高防火隔墙在防火优化后,背火面最高温度降低,最大形变降低了75.5%,耐火性与稳定性得到大幅改善,并满足《建筑构件耐火试验方法》对于防火隔墙隔热性和完整性要求。在防火隔墙设计方面,容重为50 kg/m^(2)的钢框架岩棉夹芯板超高防火隔墙,跨度方向每8 m需设一根钢柱,高度方向每3.6 m需设一根钢梁。

关键词：轻质超高防火隔墙有限元分析温度场规律形心位移

Effect of fertigation frequency on soil nitrogen distribution and tomato yield under alternate partial root-zone drip irrigation

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Journal of Integrative Agriculture 2023年第3期22卷 897-907页

作者： feng Xu-yu PU Jing-xuan LIU Hai-jun WANG Dan LIU Yu-hang QIAO Shu-ting lei Tao LIU Rong-hao College of Water Resources science and engineering Taiyuan University of TechnologyTaiyuan 030024P.R.China College of Water sciences Beijing Normal UniversityBeijing 100875P.R.China beijing Key Laboratory of Urban Hydrological Cycle and Sponge City Technology Beijing Normal UniversityBeijing 100875P.R.China Shanxi Province Key Laboratory of Soil Environment and Nutrient Resources Taiyuan 030031P.R.China

Alternate partial root-zone drip fertigation (ADF) is a combination of alternating irrigation and drip fertigation,with the potential to save water and increase nitrogen (N) fertilizer efficiency.A 2-year greenhouse experiment was conducted to evaluate the effect of different fertigation frequencies on the distribution of soil moisture and nutrients and tomato yield under *** treatments included three ADF frequencies with intervals of 3.days (F3.,6 days (F6) and 12 days (F12),and conventional drip fertigation as a control (CK),which was fertilized once every 6 *** the ADF treatments,two drip tapes were placed 10 cm away on each side of the tomato row,and alternate drip irrigation was realized using a manual valve on the distribution *** the CK treatment,a drip tape was located close to the roots of the tomato *** total N application rate of all treatments was 180 kg ha^(-1).The total irrigation amounts applied to the CK treatment were450.6 and 446.1 mm in 2019 and 2020,respectively;and the irrigation amounts applied to the ADF treatments were 60%of those of the CK *** F3.treatment resulted in water and N being distributed mainly in the 0–40-cm soil layer with less water and N being distributed in the 40–60-cm soil *** F6 treatment led to 21.0 and 29.0%higher 2-year average concentration of mineral N in the 0–20 and 20–40-cm soil layer,respectively and a 23.0%lower N concentration in the 40–60-cm soil layer than in the CK *** 2-year average tomato yields of the F3.F6,F12,and CK treatments were 107.5,102.6,87.2,and 98.7 t ha^(-1),*** tomato yield of F3.was significantly higher (23.3.) than that in the F12 treatment,whereas there was no significant difference between the F3.and F6 *** F6 treatment resulted in yield similar to the CK treatment,indicating that ADF could maintain tomato yield with a 40%saving in water *** on the distribution of water and N,and tomato yield,a fertigation frequency

关键词： alternate partial root-zone irrigation drip fertigation soil water soil mineral content tomato yield

Texture development and properties of Ti-IF steels produced by different hot-rolling processes

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Journal of Iron and Steel Research International 2019年第3期26卷 310-320页

作者： lei-lei hao Lang Li Chen-yang Qiu Jian-gong Wang Xun Zhou Yong-lin Kang School of Materials science and engineering University of Science and Technology BeijingBeijing 100083China Shougang Jingtang United Iron and Steel Co. Ltd.Tangshan 063200HebeiChina

Texture is a pivotal factor for the deep drawability of interstitial free steel (IF steel). The evolution of microstructure and recrystallization texture of Ti-IF steel through the processing of hot rolling, cold rolling and annealing have been studied. The mechanical properties including strain hardening index n and plastic strain ratio r are also measured. For comparison, ferrite rolling and austenite rolling are both studied. The results show that the intensity of γ-fiber after ferrite rolling is higher than that after austenite rolling. The great balance between the {111}〈110〉 and {111}〈112〉 leads to low △r value after annealing. The size of precipitates in ferrite rolled sample is generally larger than that in austenite rolled sample. Compared to austenite rolled sample, the ferrite rolled and annealed one has better formability and its r value reaches 2.3.. Different from laboratory production, the test steels were acquired from industrial trial, and all the result can be used in industrial production directly.

关键词： Ti-IF steel Ferrite rolling Austenite rolling Microstructure Texture

Effect of continuous annealing temperature on microstructure and properties of ferritic rolled interstitial-free steel

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International Journal of Minerals,Metallurgy and Materials 2018年第5期25卷 536-546页

作者： Chen-yang Qiu Lang Li lei-lei hao Jian-gong Wang Xun Zhou Yong-lin Kang School of Materials science and engineering University of Science and Technology BeijingBeijing 100083China Shougang Jingtang United Iron and Steel Co.Ltd. Tangshan 063200China 不详

In this report,the microstructure,mechanical properties,and textures of warm rolled interstitial-free steel annealed at four different temperatures(73.,760,790,and 820°C)were *** overall structural features of specimens were investigated by optical microscopy,and the textures were measured by X-ray diffraction(XRD).Nano-sized precipitates were then observed by a transmission electron microscope(TEM)on carbon extraction *** to the results,with increased annealing temperatures,the ferrite grains grew;in addition,the sizes of Ti_4C_2S_2 and Ti C precipitates also ***,the sizes of Ti N and Ti S precipitates slightly *** the annealing temperature increased from 73. to 820°C,the yield strength(YS)and the ultimate tensile strength(UTS)showed a decreasing ***,elongation and the strain harden exponent(n value)increased to 49.6%and 0.3.,*** comparing textures annealed at different temperatures,the intensity of{111}texture annealed at 820°C was the largest,while the difference between the intensity of{111}and{111}was the smallest when the annealing temperature was 820°***,the plastic strain ratio(r value)annealed at 820°C was the highest.

关键词： interstitial-free steel warm rolling texture mechanical properties microstructure

Sequence-dependent interactions between model peptides and lipid bilayers

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Nuclear science and Techniques 2017年第9期28卷 69-79页

作者： hao-Zhi lei Tian Tian Qiqige Du Jun HU Yi Zhang Key Laboratory of Interfacial Physics and Technology Shanghai Institute of Applied Physics Chinese Academy of Sciences Shanghai 201800 China university of Chinese Academy of sciences Beijing 100049China School of Life sciences Inner Mongolia Agricultural University Hohhot 010018 China

Studying interaction between peptides and lipid membranes is helpful for understanding the working mechanism of amyloidogenic peptides and antimicrobial peptides, which are toxic to cells through disruption of the cell membrane. Although many efforts have been made to find out common mechanisms of the peptide-induced membrane disruption, detailed information on how the peptide's amino acid sequence affects its interaction with lipid bilayers is still lacking. In this study, three peptides termed as Pep11, P11-2, and QQ11, which share a similar backbone, were employed to explore how modifications on the peptide sequence as well as terminal groups influenced its interaction with the lipid membrane. Atomic force microscopy data revealed that the peptides could deposit on the membranes and induce defects with varied morphologies and stiffness. Fluorescence resonance energy transfer(FRET) experiments indicated that the introduction of the three peptides resulted in different FRET effects on either liquid or gel lipid membranes. DPH fluorescence anisotropy and Laurdan's generalized polarization analysis showed that P11-2 could insert into the lipid membrane and impact the lipid hydrophobic region while QQ11 influenced the order of the hydrophilic head of the lipid membrane. With these results, we have illustrated how these peptides interacted differently with the lipid membrane because of the modification of their sequences. Although these peptides did not relate to disease and antibiosis, we hope these results still could provide some clues for partly understanding the working mechanism of amyloidogenic peptides and antimicrobial peptides.

关键词：氨基酸序列相互作用抗菌肽脂质膜双层模型荧光共振能量转移原子力显微镜荧光各向异性