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High Technology letters 1995年第1期1卷 102-104页

作者： Xiaowen, zh. Xueping, l. Yuan, l. Xurui, X. Songbin, zh. Zongju, X. Yinghua, Z. Academia Sinica Beijing China

ultrafine PbS particles with different sizes have been prepared in perfluorocarboxylated cation-exchanged films. The variation of PbS particle size was clarified by absorption spectra and TEM graphs. Time-resolved optical Kerr effects were measured by femtosecond pump-probe techniques. Optical Kerr effect response time was estimated to be less than 165 fs. A third-order optical nonlinearity of χ(3)10-12 esu for PbS particles was obtained and it was found that it increases with the decrease of particle sizes, showing the influence of quantum confined effect on optical nonlinear behaviour of ultrafine particles.

关键词： PbS ultrafine particle Optical nonlinearity Optical Kerr effect

Study on Single-fiber Pull-out Method for Evaluating Interfacial Strength in CFRP

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High Technology letters 1995年第1期1卷 105-108页

作者： Yudong, H. zhiqian, zh. lixun, l. Qiwei, l. Harbin Inst of Technology Harbin China

Single-fiber pull-out testing (SFPOT) methods are frequently used to evaluate the interfacial adhesion between fiber and matrix in composite materials. To make such pull-out measurements, however, the length of embedded fiber must be small enough so that the fiber does not break before it is pulled freely. This is difficult to achieve by conventional methods with fibers of small diameter, such as the carbon fibers. In this paper, a fiber pull-out experiment is described. Specialized apparatus in our laboratory, as well as this technique for sample preparation are discussed in detail. The interfacial shear strength of carbon fiber/resin matrix composites is analyzed quantitatively by using the finite-element method. The SFPOT system has been proved to be an available means for the study of interfacial properties for carbon fiber/resin matrix composites.

关键词： Carbon fiber Composite materials Interfacial shear strength Single-fiber pull-out

Wear of semi-solid rheocast SiC_p/Al metal matrix composites

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中国有色金属学会会刊：英文版 2010年第S3期20卷 852-856页

作者： u.A.CuRlE l.IVANCHEV Materials Science and Manufacturing Council for Scientific and Industrial Research(South Africa)

Rheocasting of plates in Al alloy 359 reinforced with SiC at 11%,27% and 50%(volume fractions) exhibits the capability of the council for scientific and industrial research-rheocasting system(CSIR-RCS) in rheo-processing and high pressure die casting of SiC metal matrix *** metal matrix consisting of nearly spherical proeutectic α(Al) globules was *** of fibrous eutectic silicon took place upon heat treatment of the as-cast metal matrix composites(MMCs).Hardness increases as the volume fractions of SiC *** rates of the MMCs in the F and T6 heat treatment conditions were assessed with a metallographic preparation *** is found that the 11% SiC MMC wear rate is higher on SiC abrasives compared with the 50% SiC MMC wear rate due to wear of the aluminum *** trend is reversed on diamond abrasives due to pull-out of the irregular shaped composite *** 50% SiC MMC suffers from composite particle fracture porosity after high pressure die casting(HPDC).

关键词： CSIR-RCS HPDC SiC F condition T6 condition wear rate hardness porosity

On the detection of closed orbits in time-dependent systems by using double-pulse lasers

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Communications in Theoretical Physics 2020年第9期72卷 111-117页

作者： S u Khan M l Du Institute of Theoretical Physics Chinese Academy of Sciences.Beijing 100190China university of Chinese Academy of Sciences Beijing100049China

In the photodetachment of atoms or negative ions by a double-pulse laser, the first pulse of the double-pulse laser generates waves and the delayed second pulse may detect them. The phenomenon of the excitation and detection of waves by a double-pulse laser can be used to identify the closed orbits in the system. We demonstrate this phenomenon with a negative hydrogen ion(H^-) by analyzing the total population excited by a double-pulse laser in a timedependent field for different physical parameters. By analyzing the total excited population using a double-pulse laser, we can uncover all the closed orbits existing in the system. We demonstrate that this can be realized by scanning the first pulse position and the time delay between the two pulses.

关键词： double-pulse laser detection of closed orbits photodetachment spectra time-dependent systems

Effect of densification distribution on the Young's modulus of porous coatings after nano-indentation

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Acta Metallurgica Sinica(English letters) 2012年第5期25卷 383-390页

作者： Xiaojuan l u Ping XIAO Haiyan lI School of Environment Science and Engineering North China Electric Power University Yonghua North Street Baoding 071000 China School of Materials The University of Manchester Manchester M1 7HS UK School of Mechanical Aerospace and Civil Engineering The University of Manchester P.O. Box 88Sackville Street Manchester M60 1QD UK

Nano-indentation of a porous ceramic coating leads to crushing and densification of the coating under the indenter. In this work, finite element simulations of indentation on the porous coating have been carried out to study the effect of the size and dis- tribution of densification on Youngts modulus measured by nano-indentation. Two totally different distribution patterns have been simulated in this work. In the case of gradient densification, the Youngts modulus increased by 8.6% when the densifi- cation has occurred in the maximum influenced area. While the Young^s modulus increased by 2% with a uniformed densification. Examinations of the cross-section of the coatings have suggested that the densification after the indentation is close to the second model. The measured Young＇s modulus could have differed by 2%. The effect of densification on the Young＇s modulus measured by using nano-indentation is strongly dependent on the densification patterns of the porous coating.

关键词： Film Mechanical property Finite element simulation Porosity Electron Microscopy

Fabrication of Silicon Quantum Wires by Conventional Silicon Processing

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High Technology letters 1995年第1期1卷 25-27页

作者： Yi, Sh. Jianlin, l. Feng, W. Rong, zh. Ping, H. Shulin, G. Shunming, zh. Baohua, M. Youdou, zh. Nanjing univ Nanjing China

ultra fine silicon quantum wires with the Si/SiO2 heterointerface have been fabricated successfully by using reactive ion etching, anisotropic wet chemical etching and subsequent thermal oxidation. The cross-sectional image of scanning electron microscope shows the silicon quantum wires of high quality with the linewidth down to 20nm. The present method has many remarkable advantages, which is important to the study of low-dimension quantum physics and devices.

关键词： Quantum wire Silicon Silicon dioxide Silicon technique

Variational data encoding and correlations in quantum-enhanced machine learning

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Chinese Physics B 2024年第9期33卷 298-306页

作者： Ming-Hao Wang Hua l¨u School of Physics Hubei UniversityWuhan 430062China School of Science Hubei University of TechnologyWuhan 430068China

leveraging the extraordinary phenomena of quantum superposition and quantum correlation,quantum computing offers unprecedented potential for addressing challenges beyond the reach of classical *** paper tackles two pivotal challenges in the realm of quantum computing:firstly,the development of an effective encoding protocol for translating classical data into quantum states,a critical step for any quantum *** encoding strategies can significantly influence quantum computer ***,we address the need to counteract the inevitable noise that can hinder quantum *** primary contribution is the introduction of a novel variational data encoding method,grounded in quantum regression algorithm *** adapting the learning concept from machine learning,we render data encoding a learnable *** allowed us to study the role of quantum correlation in data *** numerical simulations of various regression tasks,we demonstrate the efficacy of our variational data encoding,particularly post-learning from instructional ***,we delve into the role of quantum correlation in enhancing task performance,especially in noisy *** findings underscore the critical role of quantum correlation in not only bolstering performance but also in mitigating noise interference,thus advancing the frontier of quantum computing.

关键词： quantum machine learning variational data encoding quantum correlation

Effects of slag fineness on durability of mortars

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Journal of zhejiang university-Science A(Applied Physics & Engineering) 2007年第11期8卷 1725-1730页

作者： TOPu lker Bekir BlR Turhan Department of Civil Engineering Eski■ehir Osmangazi university Eski■ehir 26480 Turkey

In recent years, the usages of by-products and wastes in industry have become more important. The importance of the sustainable development is also of increasing. The utilizations of wastes, as mineral admixture or fine aggregate, reduce the consumption of the natural resources and improve the durability of concrete. In this study, the effect of the fineness on the high temperature and sulphate resistances of concrete mortar specimens, produced with ground granulated blast-furnace slag (GBFS) replacing cement, is investigated. The compressive and flexural strength test results for all series related to durability effects, exposing temperature and solutions, exposure times for these durability effects, slag content and fineness are discussed. Conse- quently, the optimum slag contents are determined for producing the sulphate and high temperature resistant mortars.

关键词： Cement Fineness Ground slag High temperature effect Sulphate attack Sustainable development

Designing a practical ATM Campus Network

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High Technology letters 1995年第1期1卷 61-65页

作者： Bin, l. Yong, zh. Shiduan, Ch. Yan, M. Beijing univ of Posts and Telecommunications Beijing China

A typical distributed ATM campus network——BuPT(Beijing university of Posts andTelecommunications)ATM Campus Network is presented in this *** network iscomposed of several small ATM switches in a distributed manner and will be connected tothe China Education and Research Network(CERNET).First,an architecture of BuPTATM Campus Network is *** the interworking and protocol conversion be-tween ATM network and existing 802.X lAN are ***,some of the typicalbroadband applications such as multimedia communications,virtual workgroups,remotevideo-teaching and lAN emulation are described.

关键词： ATM Campus network lAN CERNET Broadband services

Soliton Transmission over 50Km at 2.5GHz Repetition Rate

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High Technology letters 1995年第1期1卷 22-24页

作者： Shan, zh. Minyu, Y. Baoxi, X. Caiyun, l. Jinghui, l. Xin, J. Jiangde, P. Yizhi, G. Binkun, zh. Tsinghua univ Beijing China

A 2.5 GHz optical soliton transmission over 50km has been successfully achieved’for thefirst time in China by using erbium-doped fiber *** soliton pulse width is *** erbium-doped fiber amplifiers are pumped by InGaAs... 详细信息

关键词： Optical soliton Soliton transmission Soliton communication EDFA