检索结果-南通市图书馆

Surface Texturing of TiO_2 Film by Mist Deposition of TiO_2 Nanoparticles

在线全文

学校读者我要写书评

暂无评论

Nano-Micro Letters 2013年第2期5卷 129-134页

作者： Gang Qin akira Watanabe Institute of Multidisciplinary Research for Advanced Materials Tohoku University School of Materials Science and Engineering Henan Polytechnic University

Unique and various microstructures of titanium oxide(TiO_2 ) film including macroporous structure, chromatic veins and rings, have been easily fabricated by mist deposition method on silicon substrate with mild preparation conditions. Rutile phase TiO_2 nanoparticles were directly used as starting material to prepare film and led to a simple preparation process. It was found that several different microstructures existed in the sample and changed with the varied positions from the center to the edge of the film when the concentration of the TiO_2 suspension is 0.06 mol/l, the deposition time is 30 min, the flow rate is 1 l/min and the temperature is150. The surface texturing shows apparent distinction as the concentration of the TiO_2 suspension decreased to 0.03 mol/l and 0.01 mol/l.

关键词： Mist deposition TiO2 film TiO2 nanoparticle Surface texturing Microstructure

Dynamic distribution of TTK in HeLa cells: insights from an ultrastructural study

在线全文

学校读者我要写书评

暂无评论

Cell Research 2003年第6期13卷 443-449页

作者： akira SAWAGECHI,LAWRENCE BRAKO Department of Molecular and Cell Biology University of California Berkeley CA 94720 USA Electron Microscopy Facility Morhouse School of Medicine Atlanta GA 30310 USA

Entry into mitosis is driven by signaling cascades of mitotic kinases. Our recent studies show that TTK, a kinetochore-associated protein kinase, interacts with CENP-E, a mitotic kinesin located to corona fiber of kinetochore. Using immunoelectron microscopy, here we show that TTK is present at the nuclear pore adjacent complex of interphase HeLa cells. Upon nuclear envelope fragmentation, TTK targets to the outermost region of the developing kinetochores of monoorient chromosome as well as to spindle poles. After stable attachment, throughout chromosome congression, TTK is a constituent of the corona fibers, extending up to 90 nm away from the kinetochore outer plate. Upon metaphase alignment, TTK departs from the kinetochore and migrates toward the centrosomes. Taken together, this evidence strongly supports a model in which TTK functions in spindle checkpoint signaling cascades at both kinetochore and centrosome.

关键词： mitosis kinetochore TTK.

Growth phase dependent changes in the structure and protein composition of nucleoid in Escherichia coli

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

Science China(Life Sciences) 2015年第9期58卷 902-911页

作者： TALUKDER AliAzam ISHIHAMA akira Department of Microbiology Jahangirnagar University Micro-Nano Technology Research Center Hosei University Department of Molecular Genetics National Institute of Genetics

The genomic DNA of bacteria is highly compacted in a single or a few bodies known as nucleoids. Here, we have isolated Escherichia coli nucleoid by sucrose density gradient centrifugation. The sedimentation rates, structures as well as pro- tein/DNA composition of isolated nucleoids were then compared under various growth phases. The nucleoid structures were found to undergo changes during the cell growth; i. e., the nucleoid structure in the stationary phase was more tightly com- pacted than that in the exponential phase. In addition to factor for inversion stimulation （Fis）, histone-like nucleoid structuring protein （H-NS）, heat-unstable nucleoid protein （HU） and integration host factor （IHF） here we have identified, three new can- didates of E. coli nucleoid, namely DNA-binding protein from starved cells （Dps）, host factor for phage QJ3 （Hfq） and sup- pressor of taC phenotype A （StpA）. Our results reveal that the major components of exponential phase nucleoid are Fis, HU, H-NS, StpA and Hfq, while Dps occupies more than half of the stationary phase nucleoid. It has been known for a while that Dps is the main nucleoid-associated protein at stationary phase. From these results and the prevailing information, we propose a model for growth phase dependent changes in the structure and protein composition of nucleoid in E. coli.

关键词： growth phase sucrose gradient bacterial nucleoid DNA binding protein DNA compaction

强震损伤格栅墙处理地基抗液化性能离心模型试验研究

在线全文

学校读者我要写书评

暂无评论

岩土工程学报 2024年第S1期46卷 11-15页

作者：周燕国曹渊石川明陈云敏浙江大学软弱土与环境土工教育部重点实验室浙江大学岩土工程研究所浙江大学超重力研究中心浙江杭州310058 清水建设技术研究所日本东京135-8530

水泥土格栅墙能有效减缓被围束土体在地震作用下的剪切荷载及变形,已广泛应用为一种高效的抗液化对策。针对其长期服役过程,开展了两组超重力离心模型试验以研究强振历史对水泥土格栅墙内被围束土体液化响应的影响。两组模型均由15 m厚... 详细信息

水泥土格栅墙能有效减缓被围束土体在地震作用下的剪切荷载及变形,已广泛应用为一种高效的抗液化对策。针对其长期服役过程,开展了两组超重力离心模型试验以研究强振历史对水泥土格栅墙内被围束土体液化响应的影响。两组模型均由15 m厚的易液化含黏粒砂土和2.5 m厚的粗砂层组成。其中,一组模型采用水泥土格栅墙对易液化层进行加固;另一组模型则未进行处理,作为自由场地对照组。两组模型均经历振幅为0.15g的振动事件,且在0.15g振动事件前,对两组模型施加振幅为0.4g的振动事件作为强振历史。试验结果表明,格栅墙在强振下主要的损伤模式表现为竖向贯穿型裂缝,并部分伴随有局部斜向裂缝,且外侧格室对于中心格室表现出类似于群桩基础的“遮蔽效应”。强振历史后,格栅墙中心格室内被围束土体的超静孔压显著低于自由场地,损伤后格栅墙仍具有良好的抗液化效果。同时,格栅墙由于强振后整体刚度的削弱,其与下卧粗砂层间的剪切变形显著减小。

关键词：地震液化水泥土格栅墙地基处理离心机模型试验地震历史

Functionally Graded Dual-nanoparticulate-reinforced Aluminium Matrix Bulk Materials Fabricated by Spark Plasma Sintering

在线全文

学校读者我要写书评

暂无评论

Journal of Materials Science & Technology 2014年第8期30卷 736-742页

作者： Hansang Kwon Marc Leparoux akira Kawasaki Department of Materials System Engineering Pukyong National University365 Sinsenro608-759 BusanKorea Empa Swiss Federal Laboratories for Materials Science and TechnologyAdvanced Materials ProcessingFeuerwerkerstrasse 39CH-3602 ThunSwitzerland Department of Materials Processing Engineering Graduate School of EngineeringTohoku University980-8579 SendaiJapan

Functionally graded（FG） carbon nanotubes（CNT） and nano-silicon carbide（nSiC） reinforced aluminium（Al）matrix composites have been successfully fabricated using high-energy ball milling followed by solid-state spark plasma sintering *** CNTs were well-dispersed in the Al particles using the nSiC as a solid mixing *** different types of multi-walled CNTs were used to add different amounts of CNTs in the same *** ball milled Al—CNT—nSiC and Al—CNT powder mixtures were fully densified and demonstrated good adhesion with no serious microcracks and pores within an FG multilayer *** layer contained different amounts of the CNTs,and the nSiC additions showed different microstructures and *** is possible to control the characteristics of the FG multilayer composite through the efficient design of an Al—CNT—nSiC gradient *** concept offers a feasible approach for fabricating the dualnanoparticulate-reinforced Al matrix nanocomposites and can be applied to other scenarios such as polymer and ceramic systems.

关键词： Carbon nanotubes(CNT) Silicon carbide High-energy ball milling Spark plasma sintering(SPS) Functionally graded materials(FGM)

Optimization of the gain in Yb^(3+)-doped cubic laser crystals of 99.99% purity

在线全文

学校读者我要写书评

暂无评论

Journal of Rare Earths 2009年第4期27卷 616-618页

作者： Georges Boulon Yannick Guyot akira Yoshikawa Physical Chemistry of Luminescent Materials University Claude Berna rd/Lyon1 UMR 5620 CNRS Bt.A.Kastler Domaine Scientifique de La Doua 69622 Villeurbanne France IMRAM Tohoku University 2-1-1 Katahira Aoba-ku Sendai 980-8577 Japan

This was an outlook on the prediction of the infrared laser potentiality from concentration dependences of the 2F5/2 experimental decay time in Yb3＋-doped solid-state crystals mainly on cubic crystals with 99.99% pur... 详细信息

关键词： ytterbium fluoride garnet sesquioxide laser crystals concentration quenching self trapping lifetime

Luminescence of Er^(3+) in Oxyfluoride Transparent Glass-Ceramics

在线全文

学校读者我要写书评

暂无评论

Journal of Rare Earths 2006年第6期24卷 699-705页

作者： akira Ueda Steven H Morgan Richard Mu Department of Physics Fisk University NashvilleTN 37208 USA

Erbium doped silicate, germanate, and tellurium-germanate oxyfluoride glasses were prepared in a bulk form. Through appropriate heat treatment of the as-prepared glasses, transparent glass-ceramics （TGCs） were obtained with the formation of β-PbF2：Er^3＋ nanocrystals in the glass matrix were confirmed by X-ray ***-defined diffraction peaks were observed in the samples after heat-treatment. The average crystal diameter of these precipitated crystals from full-width at half-maximum （FWHM） of the diffraction peak was estimated to be between 8 and 13 nm. Optical absorption, photoluminescence, and upconversion luminescence were measured on as-prepared glass and glass-ceramics. Luminescence spectra in the TGC samples revealed well-resolved, sharp stark-splitting peaks, which indicates that a majority of Er^3＋ ions has been incorporated into the crystalline phase of the nanocrystals. The intensity of the visible and near infrared luminescence mostly increases in TSG compared to that in the as-prepared glass. In 1.53 μm absorption and emission bands, the maximum absorption peak is blue-shifted from 1531 to 1507 nm, whereas the maximum emission peak is redshifted from 1535 to 1543 nm in TGC, as compared with that in glass. The bandwidth at half-maximum （BWHM） of the emission band is significantly broader in TGC than in glass, which is beneficial to the erbium-doped fiber amplifier （EDFA）. Upconversion luminescence was measured using 800 nm near-infrared light excitation. Drastically increased upconversion 1 was observed from the TGC as compared to that from their corresponding as-prepared glasses. In addition to a strong green emission centered at 545 nm because of ^4S3/2→^4I15/2 transition and a weaker red emission centered at 662 nm because of ^4F9/2→^4I15/2 transition, generally seen from the Er^3＋ doped glasses, two violet emissions centered at 410 nm because of ^2H9/2→^4I15/2 transition and centered at 379 nm because of ^4G11/2→^4I15/2 transition were also o

关键词： luminescence transparent glass-ceramics rare earths

Analysis and control of vibration of ropes in a high-rise elevator under earthquake excitation

在线全文

学校读者我要写书评

暂无评论

Earthquake Engineering and Engineering Vibration 2019年第2期18卷 447-460页

作者： Thuan Xuan Nguyen Nanako Miura akira Sone Faculty of Mechanical Engineering Kyoto Institute Technology Matsugasaki

In this research, the vibration of elevator ropes, including the main rope and compensation rope are investigated simultaneously in a high-rise elevator system under earthquake excitation. Moreover, the paper presents a new control method to restrain the sway of both ropes. This study considers varying rope lengths during elevator operation which cause other system parameters such as natural frequency, and damping ratio to be time-variant variables. The dynamics of the ropes are analyzed by solving the governing non-stationary, nonlinear equation numerically. In order to mitigate the vibration of ropes in several motion conditions, particularly upwards movement, downward movement, stopped at the lowest position, and stopped at the highest position, an active equipment is installed at the compensation sheave. The stability of the system using the controller is analyzed at four states: without disturbance and static car, without disturbance and mobile car, including disturbance and static car, and including disturbance and mobile car. The efficiency of the controller used for dampening the vibration of elevator ropes is validated by numerical simulation results.

关键词： elevator ropes high-rise elevator vibration controller stability

IMMERSIVE VR VISUALIZATIONS BY VFIVE PART 1: DEVELOPMENT

在线全文

学校读者我要写书评

暂无评论

International Journal of Modeling, Simulation, and Scientific Computing 2013年第S1期4卷 40-53页

作者： akira KAGEYAMA NOBUAKI OHNO Graduate School of System Informatics Kobe University Kobe657-8501Japan Graduate School of Simulation Studies University of Hyogo Kobe650-0047Japan

We have been developing a visualization application for CAVE-type virtual reality(VR)systems for more than a *** application,VFIVE,is currently used in several CAVE systems in Japan for routine *** is also used as a b... 详细信息

关键词： Virtual reality CAVE immersive display system.