Pompa-García M¹, E Jurado²

Phyton-International Journal of Experimental Botany, Vol.84, No.2, pp. 385-389, 2015, DOI:10.32604/phyton.2015.84.385

Abstract Arctostaphylos pungens HBK is a dominant species with increasing abundance and distribution in chaparral ecosystems as a result of range management and, possibly, changes in climate. The value of this species for carbon (C) sequestration is unknown, and the standard 50% C out of total tree biomass is used as an approximate value. In this study, we aim to determine the C concentration of the primary components of A. pungens. The total C expressed as a percentage of biomass was determined with a Solids TOC Analyzer. We found the C concentration to vary among components. Leaves exhibited the More >

Keyong Cheng^a,b,*, Chunzi Zhang^c, Wei Chen^a,b, Shiqiang Liang^a,†, Yongxian Guo^a,d, Xiulan Huai^a

Frontiers in Heat and Mass Transfer, Vol.3, No.3, pp. 1-6, 2012, DOI:10.5098/hmt.v3.3.3003

Abstract A film cooling method with chemical heat sink for gas turbine blades is proposed. In this method, an endothermic reaction of cooling stream occurs due to the heating from the mainstream, which leads to an improvement of film cooling effectiveness. The proposed method at different blowing ratios are computed and compared with the conventional one. The simulation result shows that due to the exsitence of the chemical heat sink the proposed method can enhance film cooling effectiveness not only in the streamwise direction, but also in the spanwise direction. More >

Md. Farhad Ismail^a,*, M.A.I. Rashid^b , M. Mahbub^b

Frontiers in Heat and Mass Transfer, Vol.3, No.3, pp. 1-8, 2012, DOI:10.5098/hmt.v3.3.3002

Abstract Carbon nanotube (CNT) has been proven to be an effective material for the thermal management of MEMS-based devices due to its superior thermal conductivity. At the same time, micro-channel heat-sinks are widely used in electronic products as a high performance heat transfer device because of its simple construction, easy fabrication process and effective heat removal capability. A numerical study has been carried out to investigate the thermal-fluid characteristics of the aligned and staggered MWCNT (multi walled CNT) based micro pin fins having 650 µm long with hydraulic diameter of ~130 µm. Average heat transfer coefficients More >

M. Yakut Ali^a,*, Fanghao Yang^a, Ruixian Fang^a, Chen Li^a, Jamil Khan^a,†

Frontiers in Heat and Mass Transfer, Vol.2, No.3, pp. 1-11, 2011, DOI:10.5098/hmt.v2.3.3003

Abstract This study experimentally investigates single phase heat transfer and pressure drop characteristics of a shallow rectangular microchannel heat sink whose surface is enhanced with copper nanowires (CuNWs). The hydraulic diameter of the channel is 672 μm and the bottom wall is coated with Cu nanowires (CuNWs) of 200 nm in diameter and 50 μm in length. CuNWs are grown on the Cu heat sink by electrochemical synthesis technique which is inexpensive and readily scalable. The heat transfer and pressure drop results of CuNWs enhanced heat sink are compared with that of bare copper surface heat… More >

Ralph L. Webb

Frontiers in Heat and Mass Transfer, Vol.2, No.2, pp. 1-5, 2011, DOI:10.5098/hmt.v2.2.3001

Abstract This paper discusses the “Inlet Temperature Difference” (ITD) based heat-exchanger (and its variants) design methodology frequently used by designers of electronic heat sinks. The methodology is at variance with the accepted methodology recommended in standard heat-transfer text books – the “Log-Mean Temperature Difference” (LMTD), or the equivalent “effectiveness-NTU” design method. The purpose of this paper is to evaluate and discuss the ITD based design methodology and its deficiencies. The paper shows that the ITD based method is an approximation at best. Variants of the method can lead to either under or over prediction of the More >

Arenas Julio YR¹, R Delgado-Martínez¹, EJ Morales-Rosales², A Laguna-Cerda², O Franco-Mora², E Urbina Sánchez³

Phyton-International Journal of Experimental Botany, Vol.80, pp. 107-112, 2011, DOI:10.32604/phyton.2011.80.107

Abstract The Dahlia variabilis Wild (Desf.) is considered the Mexican national flower and their exploitation is mainly for ornamental purposes. Recent studies have shown that the tuberous roots dry weight of this species contains from 38 to 53% of a polysaccharide of fructose called inulin. The consumption of this compound does not elevate the levels of glucose in the blood of human beings, making this polysaccharide an attractive product for the food industry. This fact has helped to diversify (1) the production of Dahlia variabilis and (2) research towards the production of their roots. The aim of this… More >

Peter Kasten^a, Severin Zimmermann^a, Manish K. Tiwari^a, Bruno Michel^b, Dimos Poulikakos^a,*

Frontiers in Heat and Mass Transfer, Vol.1, No.2, pp. 1-10, 2010, DOI:10.5098/hmt.v1.2.3006

Abstract Electronic data center cooling using hot water is proposed for high system exergetic utility. The proof-of-principle is provided by numerically modeling a manifold micro-channel heat sink for cooling microprocessors of a data center. An easily achievable 0.5l/min per chip water flow, with 60°C inlet water temperature, is found sufficient to address the typical data center thermal loads. A maximum temperature difference of ~8°C was found between the solid and liquid, confirming small exergetic destruction due to heat transport across a temperature differential. The high water outlet temperature from the heat sink opens the possibility of More >

Kunigal N. Shivakumar¹, Anil Bhargava², Sameer Hamoush³

CMC-Computers, Materials & Continua, Vol.6, No.2, pp. 71-92, 2007, DOI:10.3970/cmc.2007.006.071

Abstract A detailed and accurate three-dimensional finite element stress analysis was conducted on countersunk rivet holes in a plate subjected to tension loading. The analysis included a wide range of countersunk depths, plate thicknesses, countersunk angles and plate widths. The study confirmed some of the previous results, addressed their differences, provided many new results, and investigated countersunk angle and width effects. Using the detailed FE results and the limiting conditions, a general equation for stress concentration was developed and verified. More >