For determining the effect of tree-age on the fuel properties of Eucalyptus hybrid, the variability in basic density, calorific value, proximate and ultimate parameters of 2-6 years old trees and mature trees （20- ye...For determining the effect of tree-age on the fuel properties of Eucalyptus hybrid, the variability in basic density, calorific value, proximate and ultimate parameters of 2-6 years old trees and mature trees （20- year-old）, grown under short rotation forestry regime, were measured and analyzed. Results show that there was no significant variation in the basic density of wood for 2-6 year-old Eucalyptus hybrid, with average value of 0.55-0.58 g.cm-3; the calorific value of mature trees was higher than that of lower age trees, but the ash content was much higher in lower age trees compared to mature trees. No particular trend was observed for volatile matter content and the fixed carbon content with tree-age. In conclusion, the fuel properties of mature tree were marginally better than trees of lower age.展开更多
Plastic strain-induced phase transformations(PTs)and chemical reactions under high pressure are broadly spread in modern technologies,friction and wear,geophysics,and astrogeology.However,because of very heterogeneous...Plastic strain-induced phase transformations(PTs)and chemical reactions under high pressure are broadly spread in modern technologies,friction and wear,geophysics,and astrogeology.However,because of very heterogeneous fields of plastic strain Ep and stressσtensors and volume fraction c of phases in a sample compressed in a diamond anvil cell(DAC)and impossibility ofmeasurements ofσand Ep,there are no strict kinetic equations for them.Here,we develop a kineticmodel,finite element method(FEM)approach,and combined FEM-experimental approaches to determine all fields in strongly plastically predeformed Zr compressed in DAC,and specific kinetic equation forα-ωPT consistent with experimental data for the entire sample.Since all fields in the sample are very heterogeneous,data are obtained for numerous complex 7D paths in the space of 3 components of the plastic strain tensor and 4 components of the stress tensor.Kinetic equation depends on accumulated plastic strain(instead of time)and pressure and is independent of plastic strain and deviatoric stress tensors,i.e.,it can be applied for various above processes.Our results initiate kinetic studies of strain-induced PTs and provide efforts toward more comprehensive understanding of material behavior in extreme conditions.展开更多
文摘For determining the effect of tree-age on the fuel properties of Eucalyptus hybrid, the variability in basic density, calorific value, proximate and ultimate parameters of 2-6 years old trees and mature trees （20- year-old）, grown under short rotation forestry regime, were measured and analyzed. Results show that there was no significant variation in the basic density of wood for 2-6 year-old Eucalyptus hybrid, with average value of 0.55-0.58 g.cm-3; the calorific value of mature trees was higher than that of lower age trees, but the ash content was much higher in lower age trees compared to mature trees. No particular trend was observed for volatile matter content and the fixed carbon content with tree-age. In conclusion, the fuel properties of mature tree were marginally better than trees of lower age.
基金Support from NSF(CMMI-1943710,DMR-2246991,and XSEDE MSS170015)Army Research Office(W911NF2420145)+3 种基金Iowa State University(Vance Coffman Faculty Chair Professorship and Murray Harpole Chair in Engineering)for VIL and AD is greatly appreciatedAD also acknowledges support from INTERN supplement to NSF grant CMMI-1943710 and from HPCAT for an internship at HPCATKKP was supported by NSF(CMMI-1943710)and ISUNV work performedunder the auspicesof the U.S.Department of Energy by Lawrence Livermore National Laboratory underContractDE-AC52-07NA27344。
文摘Plastic strain-induced phase transformations(PTs)and chemical reactions under high pressure are broadly spread in modern technologies,friction and wear,geophysics,and astrogeology.However,because of very heterogeneous fields of plastic strain Ep and stressσtensors and volume fraction c of phases in a sample compressed in a diamond anvil cell(DAC)and impossibility ofmeasurements ofσand Ep,there are no strict kinetic equations for them.Here,we develop a kineticmodel,finite element method(FEM)approach,and combined FEM-experimental approaches to determine all fields in strongly plastically predeformed Zr compressed in DAC,and specific kinetic equation forα-ωPT consistent with experimental data for the entire sample.Since all fields in the sample are very heterogeneous,data are obtained for numerous complex 7D paths in the space of 3 components of the plastic strain tensor and 4 components of the stress tensor.Kinetic equation depends on accumulated plastic strain(instead of time)and pressure and is independent of plastic strain and deviatoric stress tensors,i.e.,it can be applied for various above processes.Our results initiate kinetic studies of strain-induced PTs and provide efforts toward more comprehensive understanding of material behavior in extreme conditions.
