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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) 1. Department of Chemisty Central South University of Technology 410083 Changsha China

Based on thermoelectrochemical equation for an electrode reaction, the entropy change of it can be obtained by the thermoelectrochemical technology(TECT). The entropy changes of Fe(CN)-36/Fe(CN)-46,H+/H2(P0), Cu+2/Cu and Zn+2/Zn electrode reaction systems and the dilute enthalpies of the H+, Cu2+ and Zn2+ ions under the ion concentrations studied have been determined by a specially designed thermoelectrochemical equipment. The enthalpy change and entropy change for the five systems at unlimitedly diluted concentrations agree well with the literature.

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 *** 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 *** 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

CFD Simulation of dilute Gas-Solid Flow in 90<sup>o</sup>Square Bend

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Energy and Power Engineering 2011年第3期3卷 246-252页

作者： T. A. Mikhail Walid A. Aissa S. A. Hassanein O. Hamdy 不详

Gas-solid two-phase flow in a 90? bend has been studied numerically. The bend geometry is squared cross section of (0.15 m × 0.15 m) and has a turning radius of 1.5 times the duct's hydraulic diameter. The solid phase consists of glass spheres having mean diameter of 77 μm and the spheres are simulated with an air flowing at bulk velocity of 10 m/s. A computational fluid dynamic code (CFX-TASCflow) has been adopted for the simulation of the flow field inside the piping and for the simulation of the particle trajectories. Simulation was performed using Lagrangian particle-tracking model, taking into account one-way coupling, combined with a particle-wall collision model. Turbulence was predicted using k-ε model, wherein additional transport equations are solved to account for the combined gas-particle interactions and turbulence kinetic energy of the particle phase turbulence. The computational results are compared with the experimental data present in the literature and they were found to yield good agreement with the measured values.

关键词： Gas-Solid Two-Phase Flow dilute 90oBend CFX

INVESTIGATION OF SPECTRUM CHARACTERIS TICS OF dilute DEVELOPED HOLOGRAM PLATE OF SILVER HALIDE

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Chinese Science Bulletin 1984年第8期29卷 1017-1022页

作者：张春平张光寅李增发刘治山李先宜商美茹 Department of Physics Nankai University Tianjin

In recent years, the method of dilute developed silver halide was reported to have obtained phase holograms with high diffraction efficiency. Diffraction efficiency higher than 40 percent has been reached. This dilute developed silver halide plate exhibits appreciahly higher diffraction efficiency, higher signal-to-noise ratio and better photostability than amplitude holograms and thin phase holograms using chemi-

关键词： silver halide ultrafine dilute ultraviolet visible orange emulsion diameters chemi

SEB-08 Catalyst for Manufacture of Ethylbenzene from dilute Ethylene Applied at Hainan Refining and Chemical Company

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China Petroleum Processing & Petrochemical Technology 2009年第4期11卷 37-37页

作者： [Anonymous]

The SEB-08 catalyst for manufacture of ethylbenzene from dilute ethylene developed by the SINOPEC Shanghai Petrochemical Research Institute(SPRI) has been successfully applied on the 65 kt/a unit for manufacture of et... 详细信息

关键词： manufacture Ethylene dilute zeolite xylene removed

稀H_2SO_4液滴对PCB初期腐蚀行为的影响

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中国有色金属学报 2014年第10期24卷 2565-2575页

作者：丁康康肖葵邹士文董超芳李昊然李晓刚北京科技大学腐蚀与防护中心北京100083

采用交流阻抗谱(EIS)和扫描Kelvin探针(SKP)技术研究4种表面工艺处理印制电路板(PCB)试样在不同pH值稀H2SO4液滴下的腐蚀行为,通过体视学显微镜和扫描电镜结合能谱对PCB上液滴扩展和腐蚀行为进行观察分析。结果表明:覆铜板(PCB-Cu)在液... 详细信息

采用交流阻抗谱(EIS)和扫描Kelvin探针(SKP)技术研究4种表面工艺处理印制电路板(PCB)试样在不同pH值稀H2SO4液滴下的腐蚀行为,通过体视学显微镜和扫描电镜结合能谱对PCB上液滴扩展和腐蚀行为进行观察分析。结果表明:覆铜板(PCB-Cu)在液滴作用下发生全面腐蚀;无电镀镍金处理电路板(PCB-ENIG)主要为微孔腐蚀,腐蚀微孔数目由液滴边缘向液滴中心区域逐渐递减,而化学浸银处理电路板(PCB-ImAg)的腐蚀仅局限于液滴边缘,两者基底金属均发生了不同程度的腐蚀;热风整平无铅喷锡板(PCB-HASL)的腐蚀最轻微。结合EIS和SKP分析表明:稀H2SO4能够活化液滴作用区域,增大试样表面电位差,从而促进试样腐蚀;整体上,PCB-ENIG试样的耐蚀防护性能略优于PCB-ImAg试样的,PCB-HASL的最优。

关键词：覆铜板无电镀镍金化学浸银稀H2SO4 dilute H2SO4

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： WANG Wen-Rong LIANG Chen LI Tie YANG Heng LU Na WANG Yue-Lin 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 *** single crystal domains of graphene are synthesized on electroplated Cu under dilute methane gas *** 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： YAN Yue WU Biao 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 *** is found that as the fraction increases,the shape of the distribution function changes from Lorentzian to *** addition,sub-peaks can be induced in the distribution function by non-cubic lattice *** 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

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