Xinyu Zhang¹, Wenjie Xia², Yang Wang^3,4, Liang Wang^1,*, Xiaofeng Liu¹

CMES-Computer Modeling in Engineering & Sciences, Vol.139, No.3, pp. 3047-3061, 2024, DOI:10.32604/cmes.2023.046922

Abstract Graphene aerogel (GA), as a novel solid material, has shown great potential in engineering applications due to its unique mechanical properties. In this study, the mechanical performance of GA under high-velocity projectile impacts is thoroughly investigated using full-atomic molecular dynamics (MD) simulations. The study results show that the porous structure and density are key factors determining the mechanical response of GA under impact loading. Specifically, the impact-induced penetration of the projectile leads to the collapse of the pore structure, causing stretching and subsequent rupture of covalent bonds in graphene sheets. Moreover, the effects of temperature on the mechanical performance of… More >

Kevin W. Irick^*

Frontiers in Heat and Mass Transfer, Vol.8, pp. 1-7, 2017, DOI:10.5098/hmt.8.2

Abstract The Single-sided Guarded Hot Plate Method for Comparative Testing of Thermal Radiation Barriers in Vacuum was used to evaluate the performance of a variety of aerogel insulation specimens manufactured by Aspen Aerogels® against one another and against multi-layer insulation (MLI). Testing at the Air Force Research Laboratory (AFRL) shows that the effective thermal resistance, R_e, of all tested aerogel specimens are virtually bounded by the performance of 5-layer and 10-layer MLI specimens over a mean specimen temperature, T_m, range of about 270K to 315K. More >

Jiahao Wang¹, Jie Zhou², Zhengping Zhao^2,*, Feng Chen¹, Mingqiang Zhong¹

Journal of Renewable Materials, Vol.11, No.8, pp. 3309-3332, 2023, DOI:10.32604/jrm.2023.027278

Abstract Three-dimensional C/SiOx nanofiber anode was prepared by polydimethylsiloxane (PDMS) and polyacrylonitrile (PAN) as precursors via electrospinning and freeze-drying successfully. In contrast to conventional carbon covering Si-based anode materials, the C/SiOx structure is made up of PAN-C, a 3D carbon substance, and SiOx loading steadily on PAN-C. The PAN carbon nanofibers and loaded SiOx from pyrolyzed PDMS give increased conductivity and a stable complex structure. When employed as lithium-ion batteries (LIBs) anode materials, C/SiOx-1% composites were discovered to have an extremely high lithium storage capacity and good cycle performance. At a current density of 100 mA/g, its reversible capacity remained at… More > Graphic Abstract

Kevin W. Irick^a , Sally M. Smith^b , Andrew D. Williams^b,* , Derek W. Hengeveld^c , Joy M. Stein^b

Frontiers in Heat and Mass Transfer, Vol.12, pp. 1-5, 2019, DOI:10.5098/hmt.12.30

Abstract This paper provides an analysis of the thermal performance of aerogel insulation used during a long-term International Space Station (ISS) flight experiment aboard Space Test Program – Houston 3 (STP-H3). The Variable emissivity device Aerogel insulation blanket, Dual zone thermal control Experiment suite for Responsive space (VADER) investigation tested a variable emissivity radiator and a new form of multi-layer insulation that used aerogel as the thermal isolator. An effort was made to evaluate the performance of the aerogel insulation over the active flight period. The available flight temperature data shows no evidence of deterioration or change in the aerogel insulation’s… More >

Yanxia Zhang¹, Tiina Nypelö^1,*, Carlos Salas¹, Julio Arboleda¹, Ingrid C. Hoeger^1,*, Orlando J. Rojas^1,2,*

Journal of Renewable Materials, Vol.1, No.3, pp. 195-211, 2013, DOI:10.7569/JRM.2013.634115

Abstract Cellulose nanofi brils (CNF), also known as nanofi brillar cellulose (NFC), are an advanced biomaterial made mainly from renewable forest and agricultural resources that have demonstrated exceptional performance in composites. In addition, they have been utilized in barrier coatings, food, transparent fl exible fi lms and other applications. Research on CNF has advanced rapidly over the last decade and several of the fundamental questions about production and characterization of CNF have been addressed. An interesting shift in focus in the recent reported literature indicates increased efforts aimed at taking advantage of the unique properties of CNF. This includes its nanoscale… More >

Yan Wu^1,*, Xinyu Wu¹, Feng Yang^2,*, Li Xu¹, Meng Sun¹

Journal of Renewable Materials, Vol.7, No.11, pp. 1181-1195, 2019, DOI:10.32604/jrm.2019.07493

Abstract The cellulose nanocrystals/graphene composite aerogel (CGA) and polyvinyl alcohol/cellulose nanocrystals/graphene composite aerogel (PCGA) were prepared by suspension titration, tert-butanol solution replacement and freeze-drying successively. The removal rates of methyl blue (MB) from water by CGA and PCGA were evaluated and the effects of additions, adsorption time, reaction temperature and pH value of CGA and PCGA on MB removal rate were discussed. It was found that the optimal concentrations of both CGA and PCGA were 2 g∙L-1 in the adsorption reaction process and the adsorption equilibrium was reached within 120 min. The higher the initial pH value of MB solution is,… More >

Dounia Bendahou^1,2, Abdelkader Bendahou¹, Bastien Seantier¹, Bénédicte Lebeau³, Yves Grohens^1,*, Hamid Kaddami^2,*

Journal of Renewable Materials, Vol.6, No.3, pp. 299-313, 2018, DOI:10.7569/JRM.2017.634185

Abstract Hybrid aerogels have been prepared by freeze-drying technique after mixing water dispersions of cellulose microfibers or cellulose nanofibers and silica (SiO2) of type SBA-15 (2D-hexagonal). The prepared composites were characterized by different analysis techniques such as SEM, hot-filament, DMA, etc. These composites are compared to those previously prepared using nanozeolites (NZs) as mineral charge. The morphology studied by SEM indicated that both systems have different structures, i.e., individual fibers for cellulose microfibers WP-based aerogels and films for nanofibrillated cellulose NFC-based ones.... These differences seem to be driven by the charge of the particles, their aspect ratio and concentrations. These hybrid… More >

Rajendran Muthuraj, Abhishek Sachan, Mickael Castro*, Jean-François Feller, Bastien Seantier*, Yves Grohens

Journal of Renewable Materials, Vol.6, No.3, pp. 277-287, 2018, DOI:10.7569/JRM.2017.634182

Abstract In this work, thermally insulating and electrically conductive aerogels were prepared from cellulose nanofibers (CNF) and carbon nanotubes (CNTs) by environmentally friendly freeze-drying process. The thermal conductivity of neat CNF aerogel is 24 mW/(m·K) with a density of 0.025 g/cm3. With the addition of CNTs into CNF aerogel, the electrical conductivity was significantly increased while the thermal conductivity was increased to 38 mW/(m·K). Due to these interesting properties, the Seebeck coefficient and the figure of merit (ZT) of the CNF/CNTs aerogels were measured and showed that CNF/CNTs aerogel thermoelectric properties can be improved. The compressibility and electrical resistance of the… More >

Zichun Yang^1,2,3, Gaohui Su^1,4, Fengrui Sun¹

CMC-Computers, Materials & Continua, Vol.36, No.3, pp. 271-292, 2013, DOI:10.3970/cmc.2013.036.271

Abstract In this paper, we investigate the radiative properties and the effective thermal conductivity (ETC) of the opacified silica aerogel by theoretical method. The radiative properties of the opacified silica aerogel are obtained by the modified Mie Scattering Theory that is used for particle scattering in absorbing medium. The modified gamma distribution is used to take account of the non-uniformity of the particle size. The solid thermal conductivity of the composite material is obtained by considering the scale effect of the particles. Based on these calculated thermophysical properties the coupled heat conduction and radiation through the evacuated opacified aerogel are solved… More >