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Study on thermal stability of poled non-linear optical polymers

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Chinese Journal of Chemistry 1996年第5期14卷 472-480页

作者： Mhlmann G.R. vanderVorst C.P.J.M. AKZO NOBEL research laboratories Arnhem P.O.Box 93006800 SB ArnhemThe NetherlandsAKZO NOBEL Research Laboratories ArnhemP.O.Box 93006800 SB ArnhemThe NetherlandsAKZO NOBEL Research Laboratories ArnhemP.O.Box 93006800 SB ArnhemThe NetherlandsAKZO NOBEL Research Laboratories ArnhemP.O.Box 93006800 SB ArnhemThe Netherlands

A logarithmic expression is proposed to describe relaxation of the polar order in side chain polymers, together with a new way of plotting temperature dependent relaxation data. This results in a straight line extending even below the glass transition temperature in the case of poled nonlinear optics (NLO) side chain polymers. A simple procedure to determine the rotational diffusion constant D-r is given and D-r values of several polymer systems have been evaluated and compared with each other. It appears that, starting from the conventional and well known poled polymer system currently applied, a further lowering of D-r by about 3 orders of magnitude is necessary in order to reach an acceptable orientational stability or lifetime of poled polymers for practical applications. Attempts have been made to introduce electron push-pull substituents into high thermostable molecular frameworks and results of preliminary measurements are reported.

关键词： thermal stability poled polymer film organic nonlinear optical materials

JAPANESE-TO-CHINESE SPOKEN LANGUAGE TRANSLATION BASED ON THE SIMPLE EXPRESSION

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JAPANESE-TO-CHINESE SPOKEN LANGUAGE TRANSLATION BASED ON THE...

MULTIAXIAL CREEP-FATIGUE LIFE EVALUATION UNDER PROPORTIONAL LOADING

6～(th) International Conference on Spoken Language Processing

作者： Yumi WAKITA Kenji MATSUI advanced technology research laboratories Matsushita Electric Industrial Co.Ltd.KyotovJapan advanced technology research laboratories Matsushita Electric Industrial Co.Ltd.KyotovJapan

＜正＞This paper describes a Japanese-to-Chinese spoken language translation （SLT） method based on simple expression and presents the experimental results. The method is aimed at developing a compact speech translation system, which is robust for spontaneous spoken language phenomena, including the recognition errors and different expression from various speakers, The idea of translation method based on simple expression is that the mechanism interprets speech-act rather than the direct translation of the speaker’s words. The method is realized by mapping the simple expression instead of deep parsing. In this method, only keywords in speech recognition results are extracted, and the corresponding target sentences are extracted from the database by selecting similar example sentences with the keywords. All training sentences in the bilingual corpus are rewritten into the simple expression and grouped by rules. The rules are specially designed to develop the compact size example database for translation. Comparing with other example-based approaches to SLT, the method based on simple expression is easy to realize, and especially it is practical to develop the SLT systems limited in specific domains.

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Acta Metallurgica Sinica(English Letters) 2004年第4期17卷 355-360页

作者： Y.Noguchi M.Miyahara Corporate research & Development laboratories Sumitomo Metal Industries Ltd. Amagasaki Hyogo 660-0891 JapanCorporate Research & Development Laboratories Sumitomo Metal Industries Ltd. Amagasaki Hyogo 660-0891 Japan

A new method was proposed for the multiaxial creep-fatigue life evaluation under proportional loadings. Because this method was derived from the strain range partitioning method with a multiaxiality factor, it was possible to consider the influence of both creep-fatigue interaction and multiaxial stress state on fatigue life. In order to predict the combined axial-torsional fatigue life the damage under combined loading was defined as linear summation of the damages under axial loading and torsional loading. Axial-torsional creep-fatigue tests were carried out using tubular specimens of 316LC austenitic stainless steel and the ferritic rotor steel. This rotor steel was developed for the permanent magnet type eddy current retarder in heavy trucks. Experimentally obtained lives of both steels were well corresponded with the lives predicted by the proposed method. It was found that the proposed method was effective in multiaxial fatigue life evaluation under proportional creep-fatigue loadings.

关键词： multiaxial fatigue creep-fatigue proportional loading life evaluation

SAR of tricyclic sulfones as γ-secretase inhibitors

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Science China Chemistry 2011年第11期54卷 1688-1701页

作者： COLE David ASBEROM Ted BARA Tom BENNETT Chad BURNETT Duane A. CLADER John DOMALSKI Martin GREENLEE William J. HYDE Lynn JOSIEN Hubert McBRIAR Mark McKITTRICK Brian PISSARNITSKI Dmitri RAJAGOPALAN Murali SASIKUMAR Thavalakulamgara Merck research laboratories 2015 Galloping Hill RoadKenilworth New Jersey 07033 USA

Novel tricyclic sulfones as γ-secretase inhibitors have been reported by this laboratory for the treatment of Alzheimer's disease. Compounds in this series have comparable or better in vitro activities and in vivo efficacies than sulfonamide analogues re- ported previously by this laboratory. Based on the previously reported tricyclic sulfone scaffold, additional SAR studies of C ring were carried out. Various C-ring structures including cyclohexane, pyran, and piperidine were tolerated. Additionally, the 7- and 8- positions of the C-ring were identified as the best sites to introduce substituent for modulating the pharmacokinetic properties of compounds from this series.

关键词： tricyclic sulfones T-secretase Alzheimer's disease inhibitors

MCM-41 anchored sulfonic acid (MCM-41-R-SO_3H):A mild,reusable and highly efficient heterogeneous catalyst for the Biginelli reaction

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Chinese Chemical Letters 2008年第12期19卷 1435-1439页

作者： Gholam Hossein Mahdavinia Hamid Sepehrian Department of Chemistry Islamic Azad University-Marvdasht BranchMarvdashtIran Jaber lbn Hayan research laboratories Nuclear Science and Technology Research InstituteAEOIP.O.Box 11365/8486TehranIran

An efficient three-component synthesis of 3,4-dihydropyrimidinones using MCM-41 anchored sulfonic acid （MCM-41-R-SO3H） as a mild, heterogeneous catalyst for Biginelli reaction in CH3CN under reflux condition is desc... 详细信息

关键词： One-pot MCM-41-R-SO3H Heterogeneous Biginelli reaction Multicomponent

Predicting electronic structures at any length scale with machine learning

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npj Computational Materials 2023年第1期9卷 1176-1185页

作者： Lenz Fiedler Normand A.Modine Steve Schmerler Dayton J.Vogel Gabriel A.Popoola Aidan P.Thompson Sivasankaran Rajamanickam Attila Cangi Center for advanced Systems Understanding D-02826 GörlitzGermany Helmholtz-Zentrum Dresden-Rossendorf D-01328 DresdenGermany Computational Materials and Data Science Sandia National Laboratories1515 Eubank BlvdAlbuquerque 87123 NMUSA Elder research Inc.300 West Main StreetCharlottesville 22903 VAUSA Center for Computing research Sandia National Laboratories1515 Eubank BlvdAlbuquerque 87123 NMUSA

The properties of electrons in matter are of fundamental *** give rise to virtually all material properties and determine the physics at play in objects ranging from semiconductor devices to the interior of giant gas *** and simulation of such diverse applications rely primarily on density functional theory(DFT),which has become the principal method for predicting the electronic structure of *** DFT calculations have proven to be very useful,their computational scaling limits them to small *** have developed a machine learning framework for predicting the electronic structure on any length *** shows up to three orders of magnitude speedup on systems where DFT is tractable and,more importantly,enables predictions on scales where DFT calculations are *** work demonstrates how machine learning circumvents a long-standing computational bottleneck and advances materials science to frontiers intractable with any current solutions.

关键词： electronic interior frontier

Robust textile-based spoof plasmonic frequency scanning antenna for on-body IoT applications

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Science China(Information Sciences) 2024年第8期67卷 269-284页

作者： Zhao-Min CHEN Jun-Lin ZHAN Hao CHEN Ya LI Hongjun HE Wu YANG Zhen-Guo LIU Wei-Bing LU State Key Lab of Millimeter Waves School of Information Science and EngineeringSoutheast University Center for Flexible RF technology Frontiers Science Center for Mobile Information Communication and SecuritySoutheast University Future research Laboratory China Mobile Research Institute Purple Mountain laboratories

Securing a comfortable, wearable compact frequency beam scanning antenna(FBSA) with robustness to deformation, low specific absorption rate(SAR), and good coverage of the surrounding environment for Internet of Things(IoT) applications, such as on-body navigation and wireless communication is an emerging challenge. In this work, a robust textile-based spoof plasmonic frequency scanning antenna utilizing higher-order modes is presented, which is also robust to deformation caused by the activities of the human body. The innovative design of the element ensures the high-efficiency transmission of the fundamental mode of spoof surface plasmon polaritons(SSPP) structure, providing the potential of being a multifunctional composite device in the compact on-body network. Besides, an artificial magnetic conductor(AMC) is designed underneath the SSPP structure, obtaining a low SAR value(0.113 W/kg), which ensures the safety of users. As a practical realization of this concept, a textile-based spoof plasmonic antenna was fabricated in the microwave regime and the performed experimental results show the proposed antenna has a single-beam radiation characteristic with a 70° beam scanning angle range when the frequency is 4.7–6.0 GHz with a high average realized gain of 13.15 dBi. And it still maintains a steady performance when faced with structure deformation, which proves its robustness. Wireless communication quality experiments are performed to demonstrate the proposed antenna can measure the angles of targets and realize wireless signal transmission to specific targets as the frequency varies, it may find great potential in the field of on-body IoT applications.

关键词： frequency beam scanning antenna (FBSA) Internet of Things (IoT) on-body communication spoof surface plasmon polaritons (SSPP) textile-based antenna

The African Moringa is to change the lives of millions in Ethiopia and far beyond

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Asian Pacific Journal of Tropical Biomedicine 2016年第4期6卷 355-356页

作者： Solomon Habtemariam Pharmacognosy research laboratories and Herbal Analysis Services UK

Dear Editor,I vividly recall one of my medicinal plant collection trips in the southern regions of Ethiopia back in *** collecting few plants of interest,we were asking the locals to show us medicinal plants of import... 详细信息

关键词： Moringa African branches lives minutes millions collection medicinal usage collecting

Distribution Pattern of Vascular Plant Species of Mountains in Nepal and their Fate Against Global Warming

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Journal of Mountain Science 2015年第6期12卷 1345-1354页

作者： Suresh Chandra SUBEDI Khem Raj BHATTARAI Ram Prasad CHAUUDHARY Earth and Environment Department Florida International University National Herbarium and Plant laboratories Department of Plant Resources Ministry of Forest and Soil Conservation research Center for Applied Science and technology Tribhuvan University

This study aims to find the altitudinal distribution pattern of vascular plant species reported from high mountain of Nepal(Manang) along the whole Himalayan elevation gradient, and evaluate their fate against climate change. Data was gathered from multiple sources, field investigations, literatures, and herbarium specimens. Altogether, 303 vascular plant species were reported from Manang. We used a published data to calculate distribution range of each species by interpolating between its upper and lower elevation limits. The relationship between elevation and species richness is elucidated by generalized linear model. The consequence of global warming upon Manang's vascular plant species was estimated based on projected temperature change for next century and adiabatic lapse rate along the elevation gradient of the Himalayas. The vascular plant species richness has a unimodel relationship with elevation along the whole elevation gradient of Nepal as well as in three biogeographical regions of Nepal. Vascular plants of Manang are found distributed from low land Terai to high alpine regions of Nepal and their elevation distribution range varies from 200 to 4700 m. Out of 303 vascular plants of Manang, only seven species might be affected if temperature increase by 1.5°C, whereas at least 70 species will be affected with 5°C temperature increased. However, the majority of species(233 species) have wider distribution range(> 1000 m) and more than 5°C temperature tolerance range, thus they are likely to be less affected from global warming by the end of 21 st century.

关键词： Mountain Nepal Himalayas Elevation distribution range Global warming Temperature tolerance range Manang