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Small Molecule Organic Nanostructures—Fabrication and Properties

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Journal of Materials Science & Technology 2008年第4期24卷 563-568页

作者： A.b.Djurii A.M.C.Ng kai-Yin CHEUNG Man-kin FUNG Wai-kin CHAN Department of Physics University of Hong KongPokfulam RoadHong KongHong Kong SARChina Department of Chemistry University of Hong KongPokfulam RoadHong KongHong Kong SARChina

Organic materials are of great interest for the development of low cost electronic and optoelectronic devices. Although majority of research on organic materials is concerned with synthesis of novel compounds and organic thin films, organic nanostructures are attracting increasing interest in recent years. We briefly review different growth methods of organic nanostructures, which can be roughly divided into vapor deposition methods and self-assembly techniques in solution. Then we highlight some interesting properties of organic nanostructures, as well as possible applications, includinf field emission, electronic and optoelectronic devices.

关键词： Organic nanostructures Self-assembly Vapor deposition

Morphological evolution from aquatic to terrestrial in the genus Oreolalax(Amphibia,Anura,Megophryidae)

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Progress in Natural Science:Materials International 2009年第10期19卷 1403-1408页

作者： Gang Wei a,b,c,bin Wang c,Ning Xu b,Zizhong Lia,Jianping Jiang c,a Institute of Entomology,Guizhou University,Guiyang 550025,China b Centre of Ecology,Guiyang College,Guiyang 550005,China c Chengdu Institute of biology,Chinese Academy of Sciences,Chengdu 610041,China Institute of Entomology Guizhou University Guiyang 550025 China Centre of Ecology Guiyang College Guiyang 550005 China Chengdu Institute of biology Chinese Academy of Sciences Chengdu 610041 China

A phylogeny of 17 species in the genus Oreolalax is reconstructed based on 21 morphological characters from adult specimens,skeleton specimens,tadpoles and *** species groups are recognized,of which the *** species group is the most primitive,the *** species group is the second,the *** species group is the third and the *** species group is the most recently *** on the evolutional tendency of the morphological characters on the phylogenetic tree,it is proposed that the evolution of tympanum,tympanic annulus,columella,spoon-like cartilage and the web between toes reflect the habit changes from aquatic to ***,Oreolalax is regarded as one important representative genus to study further the evolution of morphological characters from aquatic to terrestrial.

关键词： Aquatic Terrestrial Morphology Evolution Oreolalax

PHONONS IN POLYACENIC CHAINS

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Chinese Journal of Polymer Science 2006年第3期24卷 229-236页

作者： O.Rafil M.Tamine b.bourahla R.Tigrine S.Amoudache A.khater Laboratoire de Physique et Chimie Quantique Laboratoire de Physique de l'Etat Condensé

We have theoretically resolved phonon excitations in quasi-two-dimensional organic crystals of polyacenic semiconductor material which may be obtained by the pyrolytic treatment of phenol-formaldehyde resin. A model for studying the dynamical properties using three polyacene chains is proposed with the aim to present the vibrational properties of this structure. It employs the formalism of solid states in two dimensions which admit phonons. A simulation process of the two-dimensional lattice structure shows that elastic waves may explain the existence of vibrational modes in the frequency range 100-400 cm^-1. The presence of acoustic and optical like phonons is discussed in terms of the elastic force constants. A hyperfine resonance structure is obtained. It allows the analysis of the dynamical evolution in thin films of polyacene. It is found that the behavior of the phonon density of states exhibits resonance between modes in the structure.

关键词： Polymers Elastic waves Surface phonons Localized modes

Tbit/s line-rate satellite feeder links enabled by coherent modulation and full-adaptive optics

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Light(Science & Applications) 2023年第9期12卷 1727-1738页

作者： Yannik Horst bertold Ian bitachon Laurenz kulmer Jannik brun Tobias blatter Jean-Marc Conan Aurélie Montmerle-bonnefois Joseph Montri béatrice Sorrente Caroline b.Lim Nicolas Védrenne Daniel Matter Loann Pommarel benedikt baeuerle Juerg Leuthold ETH Zurich Institute of Electromagnetic Fields(IEF)Gloriastrasse 358092 ZürichSwitzerland ONERA DOTAParis Saclay UniversityF-92322 ChâtillonFrance Thales Alenia Space in Switzerland Schaffhauserstrasse 5808052 ZürichSwitzerland Polariton Technologies AG 8803 RüschlikonSwitzerland Present address:Currently with LNE-SYRTE Observatoire de ParisParisFrance

Free-space optical(FSO)communication technologies constitute a solution to cope with the bandwidth demand of future satellite-ground *** may overcome the RF bottleneck and attain data rates in the order of Tbit/s with only a handful of ground ***,we demonstrate single-carrier Tbit/s line-rate transmission over a free-space channel of 53.42 km between the Jungfraujoch mountain top(3700 m)in the Swiss Alps and the Zimmerwald Observatory(895 m)near the city of bern,achieving net-rates of up to 0.94 Tbit/*** this scenario a satellite-ground feeder link is mimicked under turbulent *** adverse conditions high throughput was achieved by employing a full adaptive optics system to correct the distorted wavefront of the channel and by using polarization-multiplexed high-order complex modulation *** was found that adaptive optics does not distort the reception of coherent modulation ***,we introduce constellation modulation–a new four-dimensional bPSk(4D-bPSk)modulation format as a technique to transmit high data rates under lowest *** way we show 53 km FSO transmission of 13.3 Gbit/s and 210 Gbit/s with as little as 4.3 and 7.8 photons per bit,respectively,at a bit-error ratio of 1∙10−*** experiments show that advanced coherent modulation coding in combination with full adaptive optical filtering are proper means to make next-generation Tbit/s satellite communications practical.

关键词： Tbit/s Gbit/s polarization

Surface tension of liquid Au-bi-Sn alloys

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Rare Metals 2012年第3期31卷 250-254页

作者： Guo, Zhongnan Li, Shan Mikula, Adolf Yuan, Wenxia Department of Chemistry School of Chemical and Biological Engineering University of Science and Technology Beijing Beijing 100083 China Institute of Inorganic Chemistry/Material Chemistry University of Vienna A-1090 Vienna Austria

The surface tension of a promising lead-free solder Au-bi-Sn alloys was investigated both by the sessile-drop method and calculation. Experimental measurements were carried out for two cross-sections with the constant gold to bismuth ration of 1:1 and 1:2. For all the investigated compositions, decrease of the surface tension is observed with increasing temperature. Meanwhile, the surface tension values were also calculated based on butler’s equation, with using the newest research on thermodynamics data of Au-bi-Sn ternary system. Compared with the experimental results, a good agreement was obtained.

关键词： sessile-drop method Au-bi-Sn alloys density surface tension butler’s equation

Solvent-free aerobic oxidation of ethylbenzene over supported Ni catalysts using molecular oxygen at atmospheric pressure

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Journal of Natural Gas Chemistry 2008年第3期17卷 293-297页

作者： G.Raju P.Shiva Reddy J.Ashok b.Mahipal Reddy A.Venugopal Catalysis & Physical Chemistry Division Indian Institute of Chemical Technology

We investigated the aerobic oxidation of ethylbenzene in the absence of solvent or any additive carried out over Ni on different types of supports namely SiO2, hydroxyapatite, SbA-15, and USY Zeolites. The oxidation of ethylbenzene activities was measured in a round bottom flask immersed in oil bath at known reaction temperature. The physicochemical characteristics of the catalysts were examined by bET surface area, XRD, FT-IR and the oxidation activities were correlated with the acidities of the catalysts obtained by TPD of NH3. It was observed that both hydroxyapatite and USY （13% Na2O） supported Ni catalysts displayed higher ethylbenzene conversion and 80% selectivity towards acetophenone.

关键词： nickel SbA-15 zeolites hydroxyapatite ethylbenzene oxidation TPD of NH3

Prediction of the effectiveness of rolling dynamic compaction using artificial neural networks and cone penetration test data

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岩石力学与工程学报 2019年第1期38卷 153-170页

作者： R.A.T.M.Ranasinghe M.b.Jaksa F.Pooya Nejad Y.L.kuo School of Civil Environmental and Mining EngineeringUniversity of Adelaide

Rolling Dynamic Compaction(RDC),which is a ground improvement technique involving non-circular modules drawn behind a tractor,has provided the construction industry with an improved ground compaction capability,especially with respect to a greater influence depth and a higher speed of compaction,resulting in increased productivity. However,to date,there is no reliable method to predict the effectiveness of RDC in a range of ground conditions. This paper presents a new and unique predictive tool developed by means of artificial neural networks(ANNs) that permits a priori prediction of density improvement resulting from a range of ground improvement projects that employed 4-sided RDC modules;commercially known as"impact rollers". The strong coefficient of correlation(i.e. R>0.86) and the parametric behavior achieved in this study indicate that the model is successful in providing reliable predictions of the effectiveness of RDC in various ground conditions.

关键词： soil mechanics rolling dynamic compaction artificial neural networks cone penetration test ground improvement

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热处理豆粕饲喂生长猪的氨基酸消化率

中国饲料 2015年第24期 32-37页

作者： González-Vega J C kim b G Htoo J k Lemme A Stein H H 伊利诺斯州立大学动物科学系乌尔班纳市61801

为测定热处理对豆粕（SbM）表观回肠消化率和标准回肠消化率（SID）的影响，本试验将常规去壳豆粕（48.5%蛋白）分成4组，一份未经额外热处理，一份在125℃下高压蒸汽处理15 min，一份在125℃下高压蒸汽处理30 min，另一份在125℃下烘... 详细信息

为测定热处理对豆粕（SbM）表观回肠消化率和标准回肠消化率（SID）的影响，本试验将常规去壳豆粕（48.5%蛋白）分成4组，一份未经额外热处理，一份在125℃下高压蒸汽处理15 min，一份在125℃下高压蒸汽处理30 min，另一份在125℃下烘箱烘干30 min。制定四种豆粕-玉米淀粉型日粮配方，且每个配方只能使用上述四种豆粕中的一种，作为每种日粮中唯一氨基酸来源。用无氮日粮配方来估算基础内源性氨基酸损失。分别在初始体重为（25.3±2.0）kg的10头阉公猪回肠末端安装一个T-型瘘管。采用5×5拉丁方设计法，将试验猪分成5个日粮处理组，5个重复处理周期。每个处理周期持续7 d，在第6天和第7天收集回肠食糜。试验结果表明，随着高压蒸汽处理时间（0~30 min）的延长，蛋白质和所有氨基酸的表观回肠消化率和标准回肠消化率呈线性降低（P＜0.01）。糠氨酸含量和豆粕样品的颜色表明高压蒸汽处理导致豆粕产生美拉德反应。然而，125℃烘箱干燥30min并未改变豆粕中蛋白和氨基酸标准回肠消化率，也没有改变SbM的糠氨酸含量（P＞0.10），且烘箱处理的样品颜色表明该样品并未受到热处理破坏。总之，热蒸汽处理时间从0 min增至30 min，高压蒸汽处理豆粕的氨基酸消化率呈线性降低，降低原因很可能是由于125℃高压蒸汽处理导致豆粕产生美拉德反应。

关键词：氨基酸消化率热处理美拉德反应猪豆粕

Emission of Eu^(3+) in sol-gel oxyfluoride glass materials obtained by different preparation methods

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Journal of Rare Earths 2014年第3期32卷 269-272页

作者： M.Zadlo b.Szpikowska-Sroka L.Zur R.Czoik W.A.Pisarski Institute of Chemistry University of Silesia Szkolna 9 40-007 Katowice Poland

Silica glasses doped with Eu3＋ ions prepared by sol-gel methods were investigated. The X-ray diffraction （XRD） was used to verify the nature of the studied systems. Excitation and emission spectra of Eu3＋ ions in sol-gel glass materials were detected. Red-to-orange luminescence intensity ratios R/O related to integrated intensities of 5D0→TF2 to 5D0→7TF1 transitions and luminescence lifetimes for 5D0 state of Eu3＋ ions were determined. The results indicated that spectroscopic parameters for Eu3＋ ions strongly de- pended on reagents and their relative ratios used for sol-gel glass preparation.

关键词： sol-gel glasses europium ions luminescence rare earths