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Journal of Central South University 1998年第1期10卷 39-41页

作者： Fang Zheng Guo Lin Zhang Hengzhong Zhang Pingming(Department of Chemisty, Central South University of Technology, Changsha 410083, China) Department of Chemisty Central South University of Technology Changsha China

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关键词： thermoelectrochemistry entropy dilute enthalpy

Study on the Characteristics of Macromolecular Chains of Cellulose in dilute Solutions

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Journal of China Textile University(English Edition) 1999年第3期16卷 21-24页

作者：鲁平陈自力田原刘兆峰 China Textile Univ Shanghai China

The characteristics of macromolecular chains of cellulose in dilute solutions are discussed. Viscometry was used for the measurement of the intrinsic viscosity [η] of four cellulose samples, which were respectively dissolved in the solvent Tri-ethylenediamine cadmium hydroxide Cadoxen (Cadoxen), Cupriethylenediamine hydroxide(Cuen), iron sodium tartrate complex(EWNN) and N,N-dimethylacetamide(DMAc)with lithium chloride(LiCI, 9% w/w). The intrinsic viscosity of the four solutions decreased in the following manner:[η]DMAc/LiCl>[η]EWNN>[η]Cuen>[η]Cadoxen. The stability of cellulose (Sample α-cellulose) dissolved in solvents Cuen and EWNN was tested by plotting the intrinsic viscosity vs. time. The values of Huggins constant K_H for the cellulose samples dissolved in solvents Cadoxen,Cuen,EWNN and DMAc/LiCl (9% w/w ) were calculated.

关键词： cellulose intrinsic viscosity dilute solutions macromolecular chains .

THE PARTICLE VELOCITY DISTRIBUTION IN A RISER OF dilute CIRCULATING FLUIDIZED BED

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Chinese Journal of Chemical Engineering 1991年第2期 182-191页

作者：杨勇林金涌俞芷青汪展文白丁荣 Dept.of Chem.Eng. Tsinghua UniversityBeijing

This paper presents an experimental study on the radial and axial profiles of local particle velocity of flu-idized catalyst(FCC)particles in a circulating fluidized bed of 8000mm in height and 186mm in inside diameterwith a Fiber-Optic Probe Laser Doppler Velocimetry.It has been found that the radial profiles of local particlevelocity are parabolic,even in the centre region and steep in the region near the bed wall,and that the length ofparticle acceleration along the bed height is longer than expected.The following formula has been recommended to correlate the 1 ocal particle velocity with dilute gas-solidflow in the bed:where a,b,c and e are functions of radial positions.

关键词： radial Probe acceleration fluidized circulating positions dilute Probability correlate histogram

A Binary Supramolecular Assembly with Intense Fluorescence Emission, High pH Stability, and Cation Selectivity: Supramolecular Assembly-Induced Emission Materials

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Research 2019年第1期2019卷 772-781页

作者： Xu Wang Xin-Yue Lou Xiao-Yu Jin Feng Liang Ying-Wei Yang State Key Laboratory of Inorganic Synthesis and Preparative Chemistry International Joint Research Laboratory of Nano-Micro Architecture ChemistryCollege of ChemistryJilin University2699 Qianjin StreetChangchun 130012China Te State Key Laboratory of Refractories and Metallurgy School of Chemistry&Chemical EngineeringWuhan University of Science and TechnologyWuhan 430081China

We construct a fuorescent supramolecular system(TPE-Q_(4)⊂DSP5)of excellent tolerance to a wide range of pH by the facile selfassembly of a new pillar[5]arene bearing disulfonated arms(DSP5)with an AIE-active tetraphenylethene-based tetratopic guest bearing four quaternary ammonium binding sites(TPE-Q_(4)),which exhibits strong blue emission even in dilute aqueous solutions along with much higher quantum yield and longer fuorescence lifetime than TPE-Q_(4) itself.Tis appreciable property can be attributed to the supramolecular assembly-induced emission(SAIE)mechanism endowed by the host-guest inclusion complexation based on synthetic macrocycles.Remarkably,the enhanced fuorescence of the supramolecular assembly is quenched efciently and exclusively by ferric ions in water with a high Stern–Volmer formula constant of 1.3×10^(5) mol^(−1),demonstrating the excellent cation selectivity and visualized responsiveness in ion sensing and detection.

关键词： dilute Fluorescence attributed

An Experimental Study on the Effects of a Film Cooling Configuration and Mainstream Temperature on Depositing

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Journal of Thermal Science 2019年第2期28卷 360-369页

作者： LIU Zhengang LIU Zhenxia ZHANG Fei LIU Yanan School of Power and Energy Northwestern Polytechnical University

The effects of a film cooling configuration and mainstream temperature on the depositing of particles are experimentally studied by using plate models. The particles are generated by melting wax and atomizing it. One model has a film cooling configuration and the other does not. The experimental results show that the film cooling configuration does not influence the depositing on the leading edge of the model very significantly. However, the film cooling configuration could increase the depositing on the upper surface of the model dramatically since the flow structure on the upper surface is changed due to the film cooling configuration. The effect of the mainstream temperature on the depositing is studied by using the model with film cooling configuration. The lower and higher mainstream temperature both could reduce the depositing. However, the mechanisms are different. The lower mainstream temperature could make more molten particles become solid particles, which could rebound from the surface of the model, reducing the depositing. The higher mainstream temperature could make all particles remain molten with higher temperature. In this case, more particles could splash from the surface of the model. Therefore, there may be a mainstream temperature at which the depositing mass is maximum.

关键词： depositing film cooling dilute multiphase flow

Novel technique for measurement of coating layer thickness of fine and porous particles using focused ion beam

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Particuology 2019年第1期17卷 190-198页

作者： M. Goslinska I. Selmer C. Kleemann U.Kulozik I. Smirnova S. Heinrich Hamburg University of Technology Institute of Solids Process Engineering and Particle TechnologyDenickestr1521073 HamburgGermany Hamburg University of Technology Institute of Thermal Separation ProcessesEiJ^endorfer Str. 3821073 HamburgGermany Technical University of Munich Chair of Food and Bioprocess EngineeringWeihenstephaner Berg 185354 FreisingGermany

A novel technique for the measurement of the coating layer thickness of fine particles was developed in this work based on cross-sectioning of micrometre-sized single coated particles using focused ion beam (FIB) milling. This technique was tested on two batches of aerogel particles coated with thin coatings in a spouted bed. The FIB milling procedure consisted of two steps. First, the desired part of the coated particle was removed using a high ion beam current. The resulting cross-sectioned area was then polished using a lower ion beam current to make the cross-section clearly visible. The FIB milling process was controlled with simultaneous scanning electron microscopy (SEM). Afterwards, the coating layer thickness was evaluated using the SEM images. The coating layer was successfully applied on the porous aerogel microparticles in the spouted bed. The coating uniformity of the highly porous particles increased with increasing sprayed coating solution amount, with up to 91% of the particle pores being covered. The FIB-cross-sectioning technique using an ion beam of 2.50 nA for the first milling and 0.43 nA for polishing of the surface resulted in successful generation of cross-sections of representative particles with a visible particle core and coating layer. A coating layer thickness of approximately 700 nm was achieved on particles with sizes of below 45 μm.

关键词： Coating layer thickness Focused ion beam Microparticle Aerogel Spouted bed dilute spouting

Finite Capacitive Response at the Quantum Hall Plateau

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Chinese Physics Letters 2022年第9期39卷 53-56页

作者：赵利利林文璐 Y.J.Chung K.W.Baldwin L.N.Pfeiffer 刘阳 International Center for Quantum Materials Peking UniversityBeijing 100871China Department of Electrical Engineering Princeton UniversityPrincetonNew Jersey 08544USA

We study ultra-high-mobility two-dimensional(2D)electron/hole systems with high precision capacitance measurement.It is found that the capacitance charge appears only at the fringe of the gate at high magnetic field when the 2D conductivity decreases significantly.At integer quantum Hall effects,the capacitance vanishes and forms a plateau at high temperatures T≥300 m K,which surprisingly disappears at T≤100 m K.This anomalous behavior is likely a manifestation that dilute particles/vacancies in the top-most Landau level form Wigner crystals,which have finite compressibility and can host polarization current.

关键词： capacitance integer dilute

Origin of Ferromagnetism in Zn_(1−x)Co_(x)O Thin Films:Evidences Provided by Hard and Soft X-Ray Absorption Spectroscopy

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Chinese Physics Letters 2012年第12期29卷 223-227页

作者：席识博崔明启秦秀芳许小红徐伟郑雷周靖刘利娟杨栋亮郭志英 Institute of High Energy Physics Chinese Academy of SciencesBeijing 100049 School of Chemistry and Materials Science Shanxi Normal UniversityLinfen 041004

Although dilute magnetic semiconductors have promising potentials in spintronics applications,the mechanism of their ferromagnetism remains ambiguous.The extensive theoretical models and exotic experimental evidences provide self-consistent but usually contradictory explanations on its either intrinsic or extrinsic origins.We find room temperature ferromagnetism in a series of Zn_(1-x)Co_(x)O(0.03≤x≤0.10)thin films prepared using magnetron co-sputtering method and treated with post-annealing at temperatures 350℃ and 500℃.The origin of the ferromagnetism is investigated in terms of electronic structure combining hard x-ray absorption spectroscopy(XAS)at Zn and Co K-edge,and soft x-ray XAS at O K-edge and Co L_(2,3)-edge.The full multiple scattering theory is employed to reinforce the interpretation of the XAS spectra,which concludes that full substitution of zinc by cobalt is responsible for the room temperature ferromagnetism due to the d states of cobalt within the framework of bound magnetic polaron.Moreover,the evidence of cobalt nanoclusters is detected at highly doped and annealed samples.The first principles calculation confirms the electronic structural evidences via the formation energy.

关键词： cobalt dilute substitution

Graphene Domains Synthesized on Electroplated Copper by Chemical Vapor Deposition

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Chinese Physics Letters 2013年第2期30卷 225-227页

作者：王文荣梁晨李铁杨恒鲁娜王跃林 State Key Laboratories of Transducer Technology Science and Technology on Microsystem LaboratoryShanghai Institute of Microsystem and Information TechnologyChinese Academy of SciencesShanghai 200050 University of Chinese Academy of Sciences Beijing 100049

Electroplated Cu,which can be compatible with integrated circuit technology and large-scale silicon wafers,is explored as a substrate to synthesize graphene domains by ambient-pressure chemical vapor deposition.Hexagonal single crystal domains of graphene are synthesized on electroplated Cu under dilute methane gas flow.Scanning electron microscopy images of graphene domains grown on electroplated Cu indicate that the domain size is time-dependent,and the domains can cross Cu grain boundaries and are distributed more uniformly on electroplated Cu surface than those grown on Cu foil.

关键词： deposition. ambient dilute

Local Field Distributions in Systems with Dipolar Interaction

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Chinese Physics Letters 2012年第1期29卷 94-97页

作者：闫玥吴飙 Institute of Physics Chinese Academy of SciencesBeijing 100190 International Center for Quantum Materials Peking UniversityBeijing 100871

We investigate systematically the local field distribution functions of up-spins for systems of dipolar interaction,with particular emphasis on Ising-type lattice systems.It is found that as the fraction increases,the shape of the distribution function changes from Lorentzian to Gaussian.In addition,sub-peaks can be induced in the distribution function by non-cubic lattice structures.This is in stark contrast with a dilute gas system,where the distribution has only one Lorentzian peak for any up-spin fraction.

关键词： distribution lattice dilute