检索结果-南通市图书馆

Synthesis and Properties of a Through-Space Interacting Diradicaloid

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Precision Chemistry 2023年第3期1卷 183-191页

作者： Takuya Kodama Yasukazu Hirao Takashi kubo Department of Chemistry Graduate School of ScienceOsaka UniversityToyonakaOsaka 560-0043Japan Innovative Catalysis Science Division Institute for Open and Transdisciplinary Research Initiatives(ICSOTRI)Osaka UniversitySuitaOsaka 565-0871Japan

Knowledge about electronic structures is important to gain an understanding of the unique functional properties of *** this study,we synthesized and characterized a diradicaloid in which two phenalenyl radical sites are coupled antiferromagnetically via a through-space *** results of quantum chemical,physicochemical(^(1)H NMR,electronic absorption,cyclic voltammetry,SQUID,ESR),and chemical reactivity studies show that this diradicaloid has singlet diradical *** assessment of the nature of the bonding interaction between two radical sites in this species using DFT calculations demonstrates that a small spatial overlap between the two SOMOs in this diradicaloid provides an efficient electron exchange path for the singlet state to be substantially lower in energy than the triplet state.

关键词： through-space interaction phenalenyl radical singlet diradical diradicaloid antiferromagnetic interaction

Synthesis and mesomorphic properties of 4-(4-bromopropyloxy)-4'-(4-alkyloxybenzylidene)anilines

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Chinese Chemical Letters 2012年第7期23卷 769-772页

作者： Guan-Yeow Yeap Yew-Hong Ooi Kenji kubo Masato M.Ito Liquid Crystal Research Laboratory School of Chemical SciencesUniversiti Sains Malaysia11800 MindenPenangMalaysia Department of Environmental Engineering for Symbiosis Faculty of EngineeringSoka UniversityTokyo 192-8577Japan

This article describes the preparation and liquid crystalline properties of a new homologous series of 4-（4-bromopropyloxy）-4＇- （4-alkyloxybenzylidene）anilines in which the phenyl ring is armed by a bromopropyloxy *** thermal behavior and mesomorphic properties of the synthesized compounds were studied with particular attention given to the correlation between their phase transition temperatures and anisotropic change influenced by molecular *** the members displayed enantiotropic smectic phase except for the homologue with the longest alkyloxy chain（R = C_（18）H_（37））,exhibiting only monotropic characteristic. The presence of bromine atom from the propyloxy side chain is found to be capable of altering and influencing the mesomorphic properties.

关键词： 4-(4-Bromopropyloxy)-4'-(4-alkyloxybenzylidene)anilines Mesomorphic properties Enantiotropic smectic DSC

Direct imaging of the near field and dynamics of surface plasmon resonance on gold nanostructures using photoemission electron microscopy

在线全文

学校读者我要写书评

暂无评论

Light(Science & Applications) 2013年第1期2卷 1-8页

作者： Quan Sun Kosei Ueno Han Yu Atsushi kubo Yasutaka Matsuo Hiroaki Misawa Research Institute for Electronic Science Hokkaido UniversitySapporo 001-0021Japan Creative Research Institution Hokkaido UniversitySapporo 001-0021Japan PRESTO Japan Science and Technology AgencyKawaguchi 332-0012Japan Institute of Physics University of TsukubaTsukuba 305-8571Japan

Localized surface plasmon resonance(LSPR)can be supported by metallic nanoparticles and engineered *** understanding of the spatially resolved near-field properties and dynamics of LSPR is important,but remains experimentally *** report experimental studies toward this aim using photoemission electron microscopy(PEEM)with high spatial resolution of sub-10 *** engineered gold nanostructure arrays(such as rods,nanodisk-like particles and dimers)are investigated via PEEM using near-infrared(NIR)femtosecond laser pulses as the excitation *** the LSPR wavelengths overlap the spectrum of the femtosecond pulses,the LSPR is efficiently excited and promotes multiphoton photoemission,which is correlated with the local intensity of the metallic nanoparticles in the near ***,the local field distribution of the LSPR on different Au nanostructures can be directly explored and discussed using the PEEM *** addition,the dynamics of the LSPR is studied by combining interferometric time-resolved pump-probe technique and *** information on the oscillation and dephasing of the LSPR field can be *** results identify PEEM as a powerful tool for accessing the near-field mapping and dynamic properties of plasmonic nanostructures.

关键词： femtosecond laser local field enhancement near-field imaging photoemission electron microscopy surface plasmon resonance

Optical nature of non-substituted triphenylmethyl cation:Crystalline state emission,thermochromism,and phosphorescence

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Aggregate

Aggregate 2021年第6期2卷 99-108页

作者： Tomohiko Nishiuchi Hikaru Sotome Risa Fukuuchi Kenji Kamada Hiroshi Miyasaka Takashi kubo Department of Chemistry Graduate School of ScienceOsaka UniversityToyonakaOsakaJapan Innovative Catalysis Science Division Institute for Open and Transdisciplinary Research Initiatives(ICS-OTRI)Osaka UniversitySuitaOsakaJapan Division of Frontier Materials Science and Center for Advanced Interdisciplinary Research Graduate School of Engineering ScienceOsaka UniversityToyonakaOsakaJapan Nanomaterial Research Institute(NMRI) National Institute of Advanced Industrial Science and Technology(AIST)IkedaOsakaJapan Department of Chemistry Graduate School of Science and TechnologyKwansei Gakuin UniversitySandaHyogoJapan

Since the discovery of the triphenylmethyl(trityl)cation 120 years ago,a variety of aromatic cations having various colors and luminescence properties have been rigorously ***,differently substituted trityl cations have been synthesized,and their optical properties have been ***,the optical properties of the parent,non-substituted and highly reactive trityl cation,which was observed to be very weakly luminescent,have not been subjected to detailed *** the effort described herein,we explored the optical nature of non-substituted trityl hexafluorophosphate(PF_(6))in the crystalline *** PF_(6) was found to exist as two crystal polymorphs including a yellow(Y)and an orange(O)***,we observed that these crystalline forms display crystalline-state emission with different *** results of X-ray crystallographic analysis showed that the two polymorphs have totally different molecular packing ***,an investigation of their optical properties revealed that the O-crystal undergoes a distinct color change to yellow upon cooling as a consequence of a change in the nature of the charge transfer interaction between the cation and PF6 anion,and that both the Y-and O-crystal exhibit phosphorescence.

关键词： aggregation induced emission carbocation phosphorescence crystal phase transition thermochromism

Influence of shock absorber condition on pavement fatigue using relative damage concept

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Journal of Traffic and Transportation Engineering(English Edition) 2015年第6期2卷 406-413页

作者： Pablo kubo Cassio Paiva Adelino Ferreira Arthur Larocca Department of Civil Engineering State University of Campinas Department of Civil Engineering University of Coimbra Department of Engineering Alpha Servicos de Assessoria Tecnica Ltda

Considering the importance of the road transportation nowadays, concerns related to pavement deterioration and maintenance have become relevant subjects. Especially for commercial vehicles, the vertical dynamic load （characterized by the tire-road interaction） is directly related to wear on the road surface. Given this, the main objective of this paper is to analyse effects of vertical loads applied on the flexible pavement, considering the variation of the condition of shock absorbers from a truck＇s front suspension. The mea- surements were performed on a rigid truck, with 2 steering front axles, in a durability test track located in Brazil. With a constant load of 6 tons on the front suspension （the maximum allowed load on front axles according to Brazilian legislation）, 3 different shock absorber conditions were evaluated： new, used and failed. By applying the relative damage concept, it is possible to conclude that the variation of the shock absorber conditions will significantly affect the vertical load applied on the pavement. Although the results clearly point to a dependent relationship between the load and the condition of the shock ab- sorbers, it is recommended to repeat the same methodology, in future to analyse the influence of other quarter car model variants （such as spring rate, mass and tire spring stiffness）.

关键词： Vertical load Pavement Relative damage Shock absorber

Observation of MHD Instabilities Driven by Energetic Electrons in the Large Helical Device

在线全文

学校读者我要写书评

暂无评论

Plasma Science and Technology 2015年第4期17卷 276-279页

作者： Mitsutaka ISOBE Kunihiro OGAWA Akihiro SHIMIZU Masaki OSAKABE Shin kubo K.TOI the LHD Experiment Group National Institute for Fusion Science Toki 509-5292Japan Department of Fusion Science The Graduate University for Advanced Studies(SOKENDAI)Toki 509-5292Japan Department of Energy Engineering and Science Nagoya UniversityNagoya 464-8463Japan

Coherent magnetic fluctuations in an acoustic range of frequency have been regularly observed in low-density（n_e〈0.2×10^（19）m^（-3））plasmas with strong second harmonic electron cyclotron resonance heating（ECRH）on the Large Helical *** X-ray measurements indicated that energetic electrons are generated in these ECRH *** magnetic fluctuations are suppressed in higher density discharges where energetic electrons are not *** ECRH power modulation experiment indicated that the observed magnetohydrodynamic（MHD）mode has an acoustic nature rather than an Alfvenic nature.

关键词： LHD ECRH energetic electron MHD instability

Mechanism of superlubricity of a DLC/Si_(3)N_(4) contact in the presence of castor oil and other green lubricants

在线全文

学校读者我要写书评

暂无评论

Friction 2022年第10期10卷 1693-1706页

作者： Yun LONG Yang WANG Volker WEIHNACHT Stefan MAKOWSKI Momoji kubo Jean Michel MARTIN Maria-Isabel DE BARROS BOUCHET Ecole Centrale de Lyon Laboratory of Tribology and System DynamicsUniversity of LyonEcully 69134France Institute for Materials Research Tohoku UniversitySendai 980-8577Japan Department of Mechanical Systems Engineering Graduate School of EngineeringTohoku UniversitySendai 980-8579Japan Fraunhofer Institute for Material and Beam Technology(IWS) Dresden 01277Germany

To meet the surging needs in energy efficiency and eco-friendly lubricants,a novel superlubricious technology using a vegetable oil and ceramic materials is *** coupling different hydrogen-free amorphous carbon coatings with varying fraction of sp^(2) and sp^(3) hybridized carbon in presence of a commercially available silicon nitride bulk ceramic,castor oil provides superlubricity although the liquid vegetable oil film in the contact is only a few nanometres thick at *** a partial liquid film possibly separating surfaces in contact,local tribochemical reactions between asperities are essential to maintain superlubricity at low *** local pressure activates chemical degradation of castor oil generating graphitic/graphenic-like species on top of asperities,thus helping both the chemical polishing of surface and its chemical passivation by H and OH ***,the formation of the formation of–(CH_(2)–CH_(2))n–noligomers have been evidenced to have a major role in the friction *** simulation unveils that formation of chemical degradation products of castor oil on friction surfaces are favoured by the quantity of sp^(2)-hybridized carbon atoms in the amorphous carbon ***,tuning sp^(2)-carbon content in hydrogen-free amorphous carbon,in particular,on the top layers of the coating,provides an alternative way to control superlubricity achieved with castor oil and other selected green lubricants.

关键词： superlubricity diamond-like carbon(DLC) sp^(2)-hybridized carbon hydrogen passivation castor oil

A Forecasting Model of Required Number of Wheat Bulk Carriers for Africa

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

中国海洋经济评论 2008年第1期2卷 34-44页

作者： Masayoshi kubo Division of Maritime Logistics Sciences Graduate School of Maritime SciencesFaculty of Maritime SciencesKobe University

The ocean transportation of grain bulk carriers is promoted by development of ocean *** the development of coastal region,the cargo transportation wi11 become more and more important,especially for the resource such as grain,oil and *** this study,a model is built to estimate the number of grain bulk carriers needed for wheat based upon analyzing the relationships between Tons and Ton-miles of Africa wheat *** find that the agricultural policies greatly affect the wheat transportation to ***,using two scenarios, we predict how many ships are necessary for the maritime transportation of wheat from other places to Africa in the *** believe that this research is extremely useful to maritime transportation of wheat to Africa.

关键词： Maritime transportation coastal region development

Laparoscopic cholecystectomy for gangrenous cholecystitis in around nineties: Two case reports

在线全文

学校读者我要写书评

暂无评论

World Journal of Clinical Cases 2021年第14期9卷 3424-3431页

作者： Hiroyuki Inoue Toshiya Ochiai Hidemasa kubo Yusuke Yamamoto Ryo Morimura Hisashi Ikoma Eigo Otsuji Division of Digestive Surgery Department of SurgeryKyoto Prefectual University of MedicineKyoto 6028566Japan Department of Surgery North Medical Center Kyoto Prefectural University of MedicineKyoto 6292261Japan Division of Digestive Surgery Department of SurgeryKyoto Prefectural University of MedicineKyoto 6028566Japan

BACKGROUND Gangrenous cholecystitis is a form of acute cholecystitis which involves gangrenous alterations in the gallbladder wall and it often follows an acute and serious *** herein report on two cases of very elderly people diagnosed early with gangrenous cholecystitis,who safely underwent laparoscopic cholecystectomy(LC)and both demonstrated a good *** SUMMARY Case 1:An 89-year-old *** underwent abdominal contrast-enhanced computed tomography(CECT)due to abdominal pain and *** gallbladder wall indicated the absence of contrast enhancement,thus leading to diagnosis of gangrenous cholecystitis and she therefore underwent *** her gallbladder demonstrated diffuse necrosis and it was also partly perforated,she was able to be discharged without any serious *** 2:A 91-year-old *** made an emergency visit with a chief complaint of abdominal *** CECT revealed swelling of the gallbladder and an ambiguous continuity of the gallbladder *** was diagnosed with gangrenous cholecystitis and underwent *** gallbladder had swelling and diffuse *** her preoperative blood culture was positive,she showed a good outcome following *** Although a definite diagnosis of gangrenous cholecystitis is difficult to make prior to surgery,if an early diagnosis can be made and appropriate treatment can be carried out,then even very elderly individuals may be discharged without major complications.

关键词： Gangrenous cholecystitis Laparoscopic cholecystectomy Elderly people Critical view of safety Tokyo guidelines 2018 Case report