Yunpeng Ren, J. K. Chen^*, Yuwen Zhang

Frontiers in Heat and Mass Transfer, Vol.3, No.2, pp. 1-7, 2012, DOI:10.5098/hmt.v3.2.3001

Abstract Heat transfer in a copper film irradiated by a femtosecond (fs) laser pulse train and by an integrated dual laser beam of a nanosecond pulse with a fspulse train was studied using the semi-classical two-temperature model. The critical point model with three Lorentzian terms was employed to characterize transient optical properties for the laser energy deposition. The effects of pulse number and separation time on the thermal response were investigated. The results showed that with the same total energy in a fs-pulse train, more pulses for shorter separation time, e.g., 1 ps, and fewer pulses for longer separation time, e.g.,… More >

Dmitrii Kuzmenkov^1,*, Pavel Struchalin^1,2, Yulia Litvintsova¹, Maksim Delov¹, Vladimir Skrytnyy¹, Kirill Kutsenko¹

FDMP-Fluid Dynamics & Materials Processing, Vol.18, No.1, pp. 1-14, 2022, DOI:10.32604/fdmp.2022.018526

Abstract

Nanofluids have great potential for solar energy harvesting due to their suitable optical and thermophysical properties. One of the promising applications of nanofluids is utilization in solar collectors with the direct absorption of light (DASC). The design of a DASC requires detailed knowledge of the optical properties of nanofluids, which can be significantly affected by the particle size distribution. The paper presents the method to take into account the particle size distribution when calculating nanofluid extinction spectra. To validate the proposed model, the particle size distribution and spectral absorbance were measured for aqueous suspension with multi-walled graphite nanotubes; the minimum… More >

Jinlai Yang^1,2,3, Liangru Wu^1,2,3,*, Yanhong Pan^1,2,3, Hao Zhong^1,2,3

Journal of Renewable Materials, Vol.7, No.11, pp. 1209-1219, 2019, DOI:10.32604/jrm.2019.07896

Abstract A novel fluorescent composition was firstly isolated from natural winter fresh Moso bamboo shoots, and its optical properties were fully investigated by fluorescence spectroscopy. It could emit strong blue light both in solid and solution state, providing high fluorescence intensity in ethanol. The solution’s concentration and addition of water greatly affected the fluorescence intensity, high concentration and addition of much water could quench fluorescence. Apoptosis results showed that the fluorescent extract (0-25 mg/L) could not induce apoptosis of Hela cells. Confocal fluorescent microscopic imaging in human hepatocellular carcinoma cells (HepG2) was realized using the fluorescent extract, it could dye the… More >

N. Selvakumar^1,2, Uday Pradhan¹, S.B. Krupanidhi², Harish C. Barshilia^1,*

CMC-Computers, Materials & Continua, Vol.52, No.3, pp. 175-185, 2016, DOI:10.3970/cmc.2016.052.173

Abstract Graphene oxide was synthesized from graphite flakes using modified Hummers’ method. The interlayer spacings of graphite, graphite oxide and graphene oxide were measured using X-ray diffraction technique. The C/O atomic ratios of graphite oxide and graphene oxide were calculated from XPS measurements. The transformation of graphite to graphite oxide and finally to graphene oxide was clearly observed from the micro-Raman spectroscopy data and was confirmed from the FESEM micrographs. UV-VIS-NIR spectrophotometer was used to study the absorbance of graphene oxide and reduced graphene oxide samples. Finally, the chemically reduced graphene oxide was heat-treated in air to obtain chemically modified graphene. More >