检索结果-南通市图书馆

Journal of Energy Chemistry 2025年第1期100卷 760-769页

作者： Lin Peng Yu Bai Hang Li Meixiu Qu Zhenhua Wang Kening Sun Advanced Research institute of multidisciplinary Science Beijing Institute of Technology Beijing Key Laboratory of Chemical Power Source and Green Catalysis School of Chemistry and Chemical Engineering Beijing Institute of Technology

Lithium-sulfur （Li-S） batteries have gained great attention due to the high theoretical energy density and low cost,yet their further commercialization has been obstructed by the notorious shuttle effect and sluggish redox ***,we supply a strategy to optimize the electron structure of Ni2P by concurrently introducing B-doped atoms and P vacancies in Ni2P （Vp-B-Ni2P）,thereby enhancing the bidirectional sulfur *** study indicates that the simultaneous introduction of B-doped atoms and P vacancies in Ni2P causes the redistribution of electron around Ni atoms,bringing about the upward shift of d-band center of Ni atoms and effective d-p orbital hybridization between Ni atoms and sulfur species,thus strengthening the chemical anchoring for lithium polysulfides （LiPSs） as well as expediting the bidirectional conversion kinetics of sulfur ***,theoretical calculations reveal that the incorporation of B-doped atoms and P vacancies in Ni2P selectively promotes Li2S dissolution and nucleation ***,the Li-S batteries with Vp-B-Ni2P-separators present outstanding rate ability of 777 m A h g-1at 5 C and high areal capacity of 8.03 mA h cm-2under E/S of 5μL mg-1and sulfur loading of 7.20 mg *** work elucidates that introducing heteroatom and vacancy in metal phosphide collaboratively regulates the electron structure to accelerate bidirectional sulfur conversion.

关键词： Lithium sulfur batteries

Derailment risk and dynamics of railway vehicles in curved tracks： Analysis of the effect of failed fasteners

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

Journal of Modern Transportation 2016年第1期24卷 38-47页

作者： Silvia Morales-Ivorra Julia Irene Real Cesar Hernandez Laura Montalbain university institute for multidisciplinary mathematics Polytechnic University of Valencia 46022 Valencia Spain

The effect of the fastener＇s failure in a railway track on the dynamic forces produced in the wheel-rail contact is studied using the simulation software VAMPIRE to assess the derailment risk of two different vehicles in two curves with distinct characteristics. First, a 3D-FEM model of a real track is constructed, paying special attention to fasteners, and calibrated with displacement data obtained experimentally during a train passage. This numerical model is subsequently used to determine the track vertical and lateral stiffness. This study evidences that although the track can practically lose its lateral stiffness as a consequence of the failure of 7 consecutive fasteners, the vehicle stability would not be necessarily compromised in the flawed zone. Moreover, the results reveal that the uncompensated acceleration and the distance along which the fasteners are failed play an important role in the dynamic behavior of the vehicle-track system, influencing strongly the risk of derailment.

关键词： Railway dynamics Fasteners Derailment Curved track

Development of a vehicle-track interaction model to predict the vibratory benefits of rail grinding in the time domain

在线全文

学校读者我要写书评

暂无评论

Journal of Modern Transportation 2015年第3期23卷 189-201页

作者： Julia Irene Real Clara Zamorano José Luis Velarte Antonio Enrique Blanco university institute for multidisciplinary mathematics Polytechnic University of Valencia Foundation for the Research and Engineering in Railways

Imperfections in the wheel-rail contact are one of the main sources of generation of railway vibrations. Consequently, it is essential to take expensive corrective maintenance measures, the results of which may be unknown. In order to assess the effectiveness of these measures, this paper develops a vehicle-track interaction model in the time domain of a curved track with presence of rail corrugation on the inner rail. To characterize the behavior of the track, a numerical finite element model is developed using ANSYS software, while the behavior of the vehicle is characterized by a unidirectional model of two masses developed with VAMPIRE PRO software. The overloads obtained with the dynamic model are applied to the numerical model and then, the vibrational response of the track is obtained. Results are validated with real data and used to assess the effectiveness of rail grinding in the reduction of wheel-rail forces and the vibration generation phenomenon.

关键词： Corrugation · Dynamic overloads · Finiteelement method · Vibrations

Magnetic properties of DNA-templated Co/Cu naonoparticle chains

在线全文

学校读者我要写书评

暂无评论

Chinese Physics B 2010年第8期19卷 628-631页

作者：高有辉卫玲高春蕾夏卫星進藤大輔 Department of Physics Beijing Normal University The First institute of Oceanography institute of multidisciplinary Research for Advanced Materials Tohoku University

According to ultraviolet （UV）-vis absorption spectra recorded in the DNA metallization process, DNA-templated Co/Cu binary nanoparticle chains are fabricated by incubating genome DNA of paralichthys olivaceus muscle in CoCl2 and CuCl2 mixture solution for 20 hours and reducing the complex for 2 hours. Transmission electron microscopy observation indicates that Co and Cu nanoparticles with 20 nm in diameter were randomly dispersed on the DNA template. The superconducting quantum interference device （SQUID） measurements display that the magnetic interaction between cobalt particles is greatly decreased by the copper particle. With increasing copper content, the coercivity of the systems enhance from 9 Oe to 100 Oe （1 Oe=79.5775 A/m）.

关键词： DNA-templated Co/Cu nanoparticle magnetic interaction

Study of TiO_2 thin films on Si substrate by the photoacoustic elastic bending method

在线全文

学校读者我要写书评

暂无评论

Science China(Physics,Mechanics & Astronomy) 2013年第7期56卷 1285-1293页

作者： TODOROVI Dragan M RABASOVI Mihailo D MARKUSHEV Dragan D FRANKO Mladen TANGAR Urka Lavreni institute for multidisciplinary Research University of Belgrade institute of Physics University of Belgrade Laboratory for Environmental Research University of Nova Gorica

The quantitative photoacoustic investigation of different TiO2 thin films on Si substrates is presented using the elastic bending method. Photoacoustic signal amplitude and phase spectra versus modulation frequency were measured and analyzed using different sample thicknesses. Within the proposed method particular attention is given to the analysis of optical, thermal, elastic and structural sample parameters. Considerable focus is devoted to the fitting procedure of experimental results using the two-layer sample theoretical model. Characteristics of previously developed photoacoustic apparatus are discussed, attempting to search the ideal experimental conditions which can provide a good signal-to-noise ratio and sensitivity.

关键词： photoacoustic TiO2 thin films

Synthesis of Nitrogen-doped Titania by Solvothermal Reactions in Alcohols

在线全文

学校读者我要写书评

暂无评论

过程工程学报 2006年第3期6卷 472-476页

作者： Tsugio Sato Yohei Aida Masakazu Komatsu 殷澍 institute of multidisciplinary Research for Advanced Materials Tohoku UniversitySendai 980-8577Japan

Nitrogen-doped titania nanoparticles were obtained by the homogeneous precipitation in hexamethylenetetraminetitanium trichloride-alcohol aqueous solutions at 90 ℃ followed by heating at 190 ℃. Anatase, rutile and brookite were obtained, where the crystallite size, specific surface area and color greatly changed as 5～50 nm, 20～200 m2/g and light gray to yellow, depending on the solvent and pH. The products after calcination were yellow, indicating doping with nitrogen ion. All colored titania showed photocatalytic activity under visible light irradiation for the oxidative decomposition of nitrogen monoxide in air. Especially, the nanoparticles of anatase type nitrogen-doped titania obtained using methanol aqueous solution showed excellent photocatalytic activity.

关键词： nitrogen-doped titania solvothermal synthesis alcohol photocatalysis nitrogen monoxide decomposition

Activities of liquid Fe-As and Fe-Sb alloys saturated with carbon

在线全文

学校读者我要写书评

暂无评论

Rare Metals 2006年第5期25卷 488-491页

作者： Leandro Voisin Kimio Itagaki institute of multidisciplinary Research for Advanced Materials Tohoku UniversitySendai 980-8577Japan

A solid iron base alloy of the so-called furnace residue is often formed as a by-product in reduction smelting of lead sinter and scraps with high contents of arsenic and antimony. The use of phase separation into a liquid iron-rich alloy and a liquid lead-rich alloy in lead-iron-arsenic and lead-iron-antimony systems saturated with carbon at relatively low temperatures of about 1200~C was proposed in a new process for treating the fumace residue to recover valuable elements into the lead-rich alloy and fLx toxic arsenic into the iron-rich alloy. As a fundamental study for the proposed process, the activity coefficients and interaction parameters of the Fe-As and Fe-Sb systems saturated with carbon at 1200℃ were derived in this study, based on the determined phase relations in the Fe-Pb-As and Fe-Pb-Sb systems saturated with carbon.

关键词： activity coefficient phase relations Pb-Fe-As-C system Pb-Fe-Sb-C system lead-smelting lead-recycling

Morphology control of aluminum nitride(AlN)for a novel high-temperature hydrogen sensor

在线全文

学校读者我要写书评

暂无评论

International Journal of Minerals,Metallurgy and Materials 2020年第11期27卷 1560-1567页

作者： Angga Hermawan Yusuke Asakura Shu Yin institute of multidisciplinary Research for Advanced Material(IMRAM) Tohoku UniversitySendai 980-8577Japan

Hydrogen is a promising renewable energy source for fossil-free transportation and electrical energy ***,leaking hydrogen in high-temperature production processes can cause an explosion,which endangers production workers and surrounding *** detect leaks early,we used a sensor material based on a wide bandgap aluminum nitride(AlN)that can withstand a high-temperature *** unique AlN morphologies(rod-like,nest-like,and hexagonal plate-like)were synthesized by a direct nitridation method at 1400℃usingγ-AlOOH as a *** gas-sensing performance shows that a hexagonal plate-like morphology exhibited p-type sensing behavior and showed good repeatability as well as the highest response(S=58.7)toward a 750 ppm leak of H2 gas at high temperature(500°C)compared with the rod-like and nest-like ***,the hexagonal plate-like morphology showed fast response and recovery times of 40 and 82 s,*** surface facet of the hexagonal morphology of AlN might be energetically favorable for gas adsorption–desorption for enhanced hydrogen detection.

关键词： aluminum nitride controllable morphology direct nitridation γ-AlOOH hydrogen sensor

Studies of multilayer structure in depth direction by soft X-ray spectroscopy

在线全文

学校读者我要写书评

暂无评论

Nuclear Science and Techniques 2006年第5期17卷 257-267页

作者： M. WATANABE T. EJIMA N. MIYATA T. IMAZONO M. YANAGIHARA Shanghai Dianji university institute of Composite Materials Shanghai Jiaotong University Shanghai 200030 China Saga university Synchrotron Light Application Center Japan institute of multidisciplinary Research for Advanced Materials Tohoku University Japan institute of multidisciplinary Research for Advanced Materials Tohoku University

It is demonstrated that two kinds of soft X-ray spectroscopy are useful as nondestructive methods to in- vestigate multilayer structures modified by interdiffusion or by chemical reaction of adjoining layers in depth direc- tion. One is the total electron yield (TEY) spectroscopy involving angular dependence measurement. Using this method, it was found that in LiF/Si/LiF trilayers, the Si layers exhibited a characteristic similar to porous Si, and in CaF2/Si/CaF2 trilayers, it was found that CaF2 segregated through the Si layer. Moreover, it has been shown that the thickness of the top layer of a Mo/Si X-ray multilayer can be determined by analyzing TEY signals generated by the standing wave. The other is the soft X-ray emission spectroscopy involving spectral shape analysis. Using this method, it was found that in Mo/Si X-ray multilayers, the interdiffusion or chemical reaction giving rise to deterioration of re- flectance character occurs in as-deposited samples as well as in heated samples. In antiferromagnetic Fe/Si multilay- ers, it was confirmed that there was no existence of pure Si layers, but insulating FeSi2 layers were present. This result suggests that the source of antiferromagnetic coupling is not conduction electrons but quantum wave interference.

关键词：软X射线能谱多层结构景深方向总电子流量驻波硅化合物

Influence of FeO and sulfur on solid state reaction between MnO-SiO_2-FeO oxides and an Fe-Mn-Si solid alloy during heat treatment at 1473 K

在线全文

学校读者我要写书评

暂无评论

International Journal of Minerals,Metallurgy and Materials 2015年第8期22卷 811-819页

作者： Cheng-song Liu Shu-feng Yang Kyung-ho Kim Jing-she Li Hiroyuki Shibata Shin-ya Kitamura School of Metallurgical and Ecological Engineering University of Science and Technology Beijing institute of multidisciplinary Research for Advanced Materials Tohoku University

To clarify the influence of Fe O and sulfur on solid state reaction between an Fe-Mn-Si alloy and Mn O-Si O2-Fe O oxides under the restricted oxygen diffusion flux, two diffusion couples with different sulfur contents in the oxides were produced and investigated after heat treatment at 1473 K. The experimental results were also compared with previous work in which the oxides contained higher Fe O. It was found that although the Fe O content in the oxides decreased from 3wt% to 1wt% which was lower than the content corresponding to the equilibrium with molten steel at 1873 K, excess oxygen still diffused from the oxides to solid steel during heat treatment at 1473 K and formed oxide particles. In addition, increasing the sulfur content in the oxides was observed to suppress the diffusion of oxygen between the alloy and the oxides.

关键词： refining solid state reactions heat treatment incl