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Liu Y.,Jiangsu University | Fan Z.,Jiangsu University | Fan Z.,Jiangsu Teachers University of Technology | Ding J.-N.,Jiangsu University | And 5 more authors.
Gongneng Cailiao/Journal of Functional Materials | Year: 2010

By ball probe with diameter in micro-meter scale, the friction experiments of the doped diamond-like films are carried out. This paper focuses on the influence of plus load, adhesion and scan rate on micro-friction properties of films in micro-meter scale. Considering the influence of adhesion during analysis of the friction, emendatory Amonto function is given for the characterization of contact friction with low load. Also, the experimental phenomena between the friction coefficient and the roughness of the films' surface is explained. And based on the genuine distribution of surface roughness, equivalent contact models which is about ball probe of micro-meter size and the roughness of film surface is presented. Besides, the function of the friction f(p, φ) about load parameters (p) and surface parameters (φ) is deduced by law of transition of energy-power. Among the surface parameters that determine the friction properties, the density of the rough peak contacting with the probe on unit area plays a primary role. The developed contact model has successfully illuminated the cause for the phenomena of the fraction experiment.


Ling Z.-Y.,Jiangsu University | Zhu A.-J.,Jiangsu University | Ding J.-N.,Jiangsu University | Ding J.-N.,Jiangsu Polytechnic University | And 4 more authors.
Gongneng Cailiao/Journal of Functional Materials | Year: 2010

This article performed a numerical study by using single phase method on the effects of the Reynolds number, volume fraction and type of based fluid and nanoparticle on the convective heat transfer characteristics of nanofluids under the laminar flow conditions. The results show that the convective heat transfer coefficient of nanofluids is higher than that of the based liquid, however, which is closely related to properties of the based liquid and nanoparticle, and the volume fraction. The heat transfer coefficient of nanofluids increases with an increase in the thermal conductivity of nanoparticles and base fluid, and increases with an increase in the volume fraction of nanoparticles. The heat transfer coefficient of nanofluids almost keeps constant for Cu-water nanofluids with a fixed volume fraction, which has nothing to do with the Reynolds number.


Guo L.,Jiangsu University | Ding J.,Jiangsu University | Ding J.,Jiangsu Polytechnic University | Ding J.,Key Laboratory of New Energy Engineering | And 6 more authors.
Vacuum | Year: 2011

In this paper, p-type hydrogenated nanocrystalline (nc-Si:H) films were prepared on corning 7059 glass by plasma-enhanced chemical vapor deposition (PECVD) system. The films were deposited with radio frequency (RF) (13.56 MHz) power and direct current (DC) biases stimulation conditions. Borane (B 2H6) was a doping agent, and the flow ratio η of B2H6 component to silane (SiH4) was varied in the experimental. Films' surface morphology was investigated with atomic force microscopy (AFM); Raman spectroscopy, X-ray diffraction (XRD) was performed to study the crystalline volume fraction Xc and crystalline size d in films. The electrical and optical properties were gained by Keithly 617 programmable electrometer and ultraviolet-visible (UV-vis) transmission spectra, respectively. It was found that: there are on the film surface many faulty grains, which formed spike-like clusters; increasing the flow ratio η, crystalline volume fraction Xc decreased from 40.4% to 32.0% and crystalline size d decreased from 4.7 to 2.7 nm; the optical band gap E g opt increased from 2.16 to 2.4 eV. The electrical properties of p-type nc-Si:H films are affected by annealing treatment and the reaction pressure. © 2010 Elsevier Ltd. All rights reserved.


Guo L.-Q.,Jiangsu University | Ding J.-N.,Jiangsu University | Ding J.-N.,Jiangsu Polytechnic University | Ding J.-N.,Key Laboratory of New Energy Engineering | And 4 more authors.
Gongneng Cailiao/Journal of Functional Materials | Year: 2010

Intrinsic hydrogenated nanocrystalline silicon (nc-Si:H) films were prepared on Corning 7059 glass by plasma enhanced vapor deposition (PECVD) technique with radio frequency (RF) and DC bias stimulation. In this paper, the DC bias was changed from 50 to 250V with RF power, chamber pressure, silane and hydrogen mixing ratio and substrate temperature being kept constant. The microstructure of the films was characterized by Raman scattering, their transmittance spectroscopy was gained by transmission electron microscope (TEM). It was found that improving DC bias caused crystalline volume fractions (X c) to change. The photo absorption coefficient and extinction coefficient on the same sample turned out a declining curve as wavelength is more than 400nm, the difference of absorption coefficient and extinction coefficient at the same wavelength, optical bang gap were caused by dangling bongs concentration and the effective carrier concentration, density level of films with different X c, such as absorption and extinction coefficient were increased near 400nm and the optical band gap decreased from 1.64 to 1.96eV.


Ling Z.-Y.,Jiangsu University | Sun D.-J.,Jiangsu University | Zhang Z.-Q.,Jiangsu University | Ding J.-N.,Jiangsu University | And 5 more authors.
Gongneng Cailiao/Journal of Functional Materials | Year: 2013

TiO2-water nanofluids with different concentration were prepared by the two-step method, and the stability were researched. The viscosities of nanofluids with various mass fraction of TiO2 nanoparticles were measured at 15-40°C. The results showed that the viscosity of the nanofluids increased with increasing nanoparticles concentration and diminished exponentially with increasing temperature. Besides, the variation trends of viscosity with temperature for all concentrations of nanofluids were similar. A new equation for calculating the nanofluids viscosity by considering particle concentration and temperature was proposed based on the experimental data, which corrected the previous equations and could well predict the experimental results of TiO2-water nanofluids.


Ling Z.-Y.,Jiangsu University | Zhu A.-J.,Jiangsu University | Ding J.-N.,Jiangsu University | Ding J.-N.,Jiangsu Polytechnic University | And 4 more authors.
Nami Jishu yu Jingmi Gongcheng/Nanotechnology and Precision Engineering | Year: 2011

In this paper, both numerical simulations and experimental study were performed on the flow characteristics of Cu-water nanofluid with 1% mass faction of Cu nano-particles in different micro-channels with diameters of 25 μm and 50 μm respectively and different lengths under the pressure-driven conditions. Two-step method was adopted to prepare the stable nanofluid. The results show that the mass flow of nanofluids is in linear relations with the pressure and increases with the increase of pressure, and the behaviors of the nanofluids are in agreement with the hypothesis of one phase fluid. However, the simulation results are different from the experimental data, primarily due to the aggregation of nanoparticles in base fluids, the changes in the viscosity of the nanofluids, the size effect and the presence of boundary slip.


Ling Z.-Y.,Jiangsu University | Zhang T.-F.,Jiangsu University | Ding J.-N.,Jiangsu University | Ding J.-N.,Jiangsu Polytechnic University | And 4 more authors.
Gongneng Cailiao/Journal of Functional Materials | Year: 2011

In this article, the stability and viscosity of the Cu-water nano-fluids, with different mass faction of particles including 0.1%, 0.5% and 1%, prepared by the two-step method were investigated and compared with the results derived from classical two-phase mixture models. The result showed that the incorporation of the SDBS dispersant can significantly improves the viscosity of Cu-water nanofluids. Moreover, there is an optimal stability when the mass fraction of Cu particles is the same as the concentration of SDBS dispersant. The viscosity of the nanofluids increases with the increase of the mass fraction of the Cu particles. However, there is a deviation between the experimental data and the calculation from the formula due to the only consideration of the effect of the mass fraction of particles on the viscosity according to the theoretical models.


Ling Z.,Jiangsu University | Zou T.,Jiangsu University | Ding J.,Jiangsu University | Ding J.,Changzhou University | And 5 more authors.
Huagong Xuebao/CIESC Journal | Year: 2012

The influences of temperature, chemical dispersant, and volume fraction of nanoparticles on the shear viscosity of the nanoparticle-fluid mixture were experimentally investigated. The nanofluids including different types of nanoparticles were prepared by a two-steps method. The results showed that the shear viscosity of the mixture decreased with increasing temperature below a threshold of 60°C. Interestingly, the viscosity of Cu-water and Al 2O 3-water nanofluids increased with increasing temperature above 60°C. The Brownian motion was enhanced as temperature increased, and the moving of the nanoparticles covering surfactants would increase the viscosity. The viscosity hysteresis between the heating and cooling processes could be observed obviously. The shear viscosity of CuO-water nanofluid in this experiment was in good agreement with fluid dynamics continuum theory for the fluids without dispersant. After the dispersant was added in CuO-water nanofluid, the experimental value of shear viscosity was larger than the theoretical data. And the varying trend of viscosity was consistent with that of the dispersant. The use of surfactant had an important role in the calculation of viscosity. The viscosity of nanofluids increased with increasing particle volume fraction, but the viscosity increments for the nanofluids with the same particle volume fraction were not the same. So density, surface electrical and diameter of the nanoparticles should be considered when calculating the viscosity of nanofluids.


Guo L.,Jiangsu University of Science and Technology | Ding J.,Jiangsu University of Science and Technology | Ding J.,Changzhou University | Ding J.,Key Laboratory of New Energy Engineering | And 5 more authors.
Applied Surface Science | Year: 2011

Hydrogenated nanocrystalline silicon thin films were prepared by plasma enhanced vapor deposition technique. In our experiment, hydrogen dilution ratio RH was changed mainly, while the other parameters, such as the radio frequency power, the direct current bias value, the chamber pressure, the total gas flow and the substrate temperature were kept constant. The film's surface topography was gained by AFM. The chemical bond was confirmed by Fourier transform infrared spectra. The optical properties were characterized by transmission spectra. To consider absorption peak of stretching vibration mode of SiH3 at 2140 cm-1 and to reduce the calculation error, a hydrogen content calculation method was proposed. Effects of hydrogen dilution ratio on the deposition rate v and hydrogen content CH were investigated. The bonding mode and the force constants k of chemical bond, the structural factor f in films were changed by high hydrogen dilution ratio, which gave rise to the shift of absorption peak of infrared stretching mode and the decrease of optical band gap Eg. © 2011 Elsevier B.V. All rights reserved.


Zhang L.,Jiangsu University | Cheng G.,Jiangsu University | Ding J.,Jiangsu University | Ding J.,Key Laboratory of New Energy Engineering | And 2 more authors.
Chinese Journal of Sensors and Actuators | Year: 2012

The residual stress of the 304 stainless steel was investigated by nanoindentation method. The maximum loads were 500 μN, 1 000 μN, 1 500 μN, 2 000 μN and 2 500 μN respectively. The Suresh theoretical model was used to calculate the residual stress. Results showed that the hardness and elastic modulus of un-annealed stainless steel are constant. The hardness of un-annealed and annealed stainless steel is 5.3 GPa and 4.0 GPa and the elastic modulus are 110 GPa and 100 GPa, respectively. Sink-in phenomenon was found during the indentation experiment based on the Ansys software. The compressive residual stress value in the stainless steel(381 MPa)was observed and calculated by the nanoindentation method, which is in good agreement with the result obtained by the XRD method(350 MPa±23 MPa). This agreement demonstrated the accuracy and reliability of using the nanoindentation method for residual stress study.

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