Name: strain sensing based on multiscale composite materials reinforced with graphene nanoplatelets
Uploaded: 2016-11-07T13:00:00
Description: Watch this Scientific Journal Video about Strain Sensing Based on Multiscale Composite Materials Reinforced with Graphene Nanoplatelets at JoVE.com

The authors would like to acknowledge the Ministerio de Econom&#237;a y Competitividad of Spain Government (Project MAT2013-46695-C3-1-R) and Comunidad de Madrid Government (P2013/MIT-2862).

1. Preparation of the Functionalized Graphene Nanoplatelet Filled Epoxy for Multiscale Composite Materials
<ol>
	<li>Disperse functionalized graphene nanoplatelets (f-GNPs) into the epoxy resin.
	<ol>
		<li>Weigh 24.00 g of f-GNPs to achieve a 12 wt% of the final nanocomposite material inside a ductless fume hood.</li>
		<li>Add 143.09 g of the bisphenol A diglycidyl ether (DGEBA) monomer and manually mix it to achieve homogeneity.</li>
		<li>Disperse the f-GNPs into the monomer by a twostep method, wh...

<ol>
	<li>Farrar, C. R., Worden, K. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=An+introduction+to+structural+health+monitoring.">An introduction to structural health monitoring.</a> Philos Trans Math Phys Eng Sci. 365, 303-315 (2007).</li><li>Lorenzo, E. D., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Structural+Health+Monitoring+challenges+on+the+10-MW+offshore+wind+turbine+model.">Structural Health Monitoring challenges on the 10-MW offshore wind turbine model.</a> J Phys Conf Ser. 628, 012081 (2015).</li><li>Braga, D. F. O. O., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Advanced+design+for+lightweight+structures:+Review+and+prospects.">Advanced design for lightweight structures: Review and prospects.</a> Prog Aerosp Sci. 69, 29-39 (2014).</li><li>Garc&#236;a M&#225;rquez, F. P., Tobias, A. M., PinarP&#233;rez, J. M., Papaelias, M. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Condition+monitoring+of+wind+turbines:+Techniques+and+methods.">Condition monitoring of wind turbines: Techniques and methods.</a> Renew Energy. 46, 169-178 (2012).</li><li>Chung, D. D. L. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Self-monitoring+structural+materials.">Self-monitoring structural materials.</a> Mater Sci Eng R Reports. 22, 57-78 (1998).</li><li>Kandare, E., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Improving+the+through-thickness+thermal+and+electrical+conductivity+of+carbon+fibre/epoxy+laminates+by+exploiting+synergy+between+graphene+and+silver+nano-inclusions.">Improving the through-thickness thermal and electrical conductivity of carbon fibre/epoxy laminates by exploiting synergy between graphene and silver nano-inclusions.</a> Compos Part A Appl Sci Manuf. 69, 72-82 (2015).</li><li>Amjadi, M., Pichitpajongkit, A., Lee, S., Ryu, S., Park, I. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Highly+stretchable+and+sensitive+strain+sensor+based+on+silver+nanowire-elastomer+nanocomposite.">Highly stretchable and sensitive strain sensor based on silver nanowire-elastomer nanocomposite.</a> ACS Nano. 8, 5154-5163 (2014).</li><li>Alamusi, H. N., Fukunaga, H., Atobe, S., Liu, Y., Li, J. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Piezoresistive+strain+sensors+made+from+carbon+nanotubes+based+polymer+nanocomposites.">Piezoresistive strain sensors made from carbon nanotubes based polymer nanocomposites.</a> Sensors. 11, 10691-10723 (2014).</li><li>Njuguna, M. K. K., Yan, C., Hu, N., Bell, J. M. M., Yarlagadda, P. K. D. V. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Sandwiched+carbon+nanotube+film+as+strain+sensor.">Sandwiched carbon nanotube film as strain sensor.</a> Compos Part B Eng. 43, 2711-2717 (2012).</li><li>Liu, Y., Rajadas, A., Chattopadhyay, A. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=A+biomimetic+structural+health+monitoring+approach+using+carbon+nanotubes.">A biomimetic structural health monitoring approach using carbon nanotubes.</a> JOM. 64, 802-807 (2012).</li><li>Eswaraiah, V., Balasubramaniam, K., Ramaprabhu, S. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Functionalized+graphene+reinforced+thermoplastic+nanocomposites+as+strain+sensors+in+structural+health+monitoring.">Functionalized graphene reinforced thermoplastic nanocomposites as strain sensors in structural health monitoring.</a> J Mater Chem. 21, 12626-12628 (2011).</li><li>Chiacchiarelli, L. M., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=The+role+of+irreversible+and+reversible+phenomena+in+the+piezoresistive+behavior+of+graphene+epoxy+nanocomposites+applied+to+structural+health+monitoring.">The role of irreversible and reversible phenomena in the piezoresistive behavior of graphene epoxy nanocomposites applied to structural health monitoring.</a> Compos Sci Technol. 80, 73-79 (2013).</li><li>Le, J., Du, H., Dai, S. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Use+of+2D+Graphene+Nanoplatelets+(GNP)+in+cement+composites+for+structural+health+evaluation.">Use of 2D Graphene Nanoplatelets (GNP) in cement composites for structural health evaluation.</a> Compos Part B. 67, 555-563 (2014).</li><li>Ren, X., Burton, J., Seidel, G. D., Lafdi, K. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Computational+multiscale+modeling+and+characterization+of+piezoresistivity+in+fuzzy+fiber+reinforced+polymer+composites.">Computational multiscale modeling and characterization of piezoresistivity in fuzzy fiber reinforced polymer composites.</a> Int J Solids Struct. 54, 121-134 (2015).</li><li>Park, M., Park, J., Jeong, U. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Design+of+conductive+composite+elastomers+for+stretchable+electronics.">Design of conductive composite elastomers for stretchable electronics.</a> Nano Today. 9, 244-260 (2014).</li><li>Kim, Y. J., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Preparation+of+piezoresistive+nano+smart+hybrid+material+based+on+graphene.">Preparation of piezoresistive nano smart hybrid material based on graphene.</a> Curr Appl Phys. 11, S350-S352 (2011).</li><li>Sadeghi, M. M., Pettes, M. T., Shi, L. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Thermal+transport+in+graphene.">Thermal transport in graphene.</a> Solid State Commun. 152, 1321-1330 (2012).</li><li>Potts, J. R., Dreyer, D. R., Bielawski, C. W., Ruoff, R. S. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Graphene-based+polymer+nanocomposites.">Graphene-based polymer nanocomposites.</a> Polymer. 52, 5-25 (2011).</li><li>Zaman, I., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=A+facile+approach+to+chemically+modified+graphene+and+its+polymer+nanocomposites.">A facile approach to chemically modified graphene and its polymer nanocomposites.</a> Adv Funct Mater. 22, 2735-2743 (2012).</li><li>Moriche, R., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Morphological+changes+on+graphene+nanoplatelets+induced+during+dispersion+into+an+epoxy+resin+by+different+methods.">Morphological changes on graphene nanoplatelets induced during dispersion into an epoxy resin by different methods.</a> Compos Part B Eng. 72, 199-205 (2015).</li><li>ASTM International. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=.">.</a> ASTM D790-15e2, Standard Test Methods for Flexural Properties of Unreinforced and Reinforced Plastics and Electrical Insulating Materials. , D790 (2015).</li><li>Gong, S., Zhu, Z. H., Meguid, S. A. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Carbon+nanotube+agglomeration+effect+on+piezoresistivity+of+polymer+nanocomposites.">Carbon nanotube agglomeration effect on piezoresistivity of polymer nanocomposites.</a> Polymer. 55, 5488-5499 (2014).</li><li>Zhao, J., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Ultra-sensitive+strain+sensors+based+on+piezoresistive+nanographene+films.">Ultra-sensitive strain sensors based on piezoresistive nanographene films.</a> Appl Phys Lett. 101, 063112 (2012).</li><li>Galpaya, D., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Recent+advances+in+fabrication+and+characterization+of+graphene-polymer+nanocomposites.">Recent advances in fabrication and characterization of graphene-polymer nanocomposites.</a> Graphene. 1, 30-49 (2012).</li><li>Kanoun, O., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Flexible+Carbon+Nanotube+Films+for+High+Performance+Strain+Sensors.">Flexible Carbon Nanotube Films for High Performance Strain Sensors.</a> Sensors. 14, 10042-10071 (2014).</li><li>Zaman, I., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Epoxy/graphene+platelets+nanocomposites+with+two+leves+of+interface+strength.">Epoxy/graphene platelets nanocomposites with two leves of interface strength.</a> Polymer. 52, 1603-1611 (2011).</li><li>Chu, K., Li, W. S., Dong, H. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Role+of+graphene+waviness+on+the+thermal+conductivity+of+graphene+composites.">Role of graphene waviness on the thermal conductivity of graphene composites.</a> Appl Phys A. 111, 221-225 (2013).</li><li>Monti, M., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Morphology+and+electrical+properties+of+graphene-epoxy+nanocomposites+obtained+by+different+solvent+assisted+processing+methods.">Morphology and electrical properties of graphene-epoxy nanocomposites obtained by different solvent assisted processing methods.</a> Compos Part A. 46, 166-172 (2013).</li><li>Moazzami Gudarzi, M., Sharif, F. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Enhancement+of+dispersion+and+bonding+of+graphene-polymer+through+wet+transfer+of+functionalized+graphene+oxide.">Enhancement of dispersion and bonding of graphene-polymer through wet transfer of functionalized graphene oxide.</a> Express Polym Lett. 6, 1017-1031 (2013).</li><li>Fan, H., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Fabrication,+mechanical+properties+and+biocompatibility+of+graphene-reinforced+chitosan+composites.">Fabrication, mechanical properties and biocompatibility of graphene-reinforced chitosan composites.</a> Biomacromolecules. 11, 2345-2351 (2010).</li><li>Teomete, E. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Transverse+strain+sensitivity+of+steel+fiber+reinforced+cement+composites+tested+by+compression+and+split+tensile+tests.">Transverse strain sensitivity of steel fiber reinforced cement composites tested by compression and split tensile tests.</a> Constr Build Mater. 55, 136-145 (2014).</li><li>Nauman, S., Cristian, I., Koncar, V. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Simultaneous+Application+of+Fibrous+Piezoresistive+Sensors.">Simultaneous Application of Fibrous Piezoresistive Sensors.</a> Sensors. 11, 9478-9498 (2011).</li><li>Han, B., Ding, S., Yu, X. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Intrinsic+self-sensing+concrete+and+structures+A+review.">Intrinsic self-sensing concrete and structures A review.</a> Measurement. 59, 110-128 (2015).</li></ol>

Self-sensor properties of nanoreinforced composite materials are due to the electrical network created by the f-GNPs through the epoxy matrix and along the glass fibers, which is modified when strain is induced. Dispersion of the f-GNPs is then crucial because the electrical behavior of the sensors strongly depends on the microstructure of the material. Here, we present an optimized procedure to achieve a good dispersion of the GNPs into the epoxy matrix and to avoid wrinkling of the nanoparticles, which causes the detri...

Structural health monitoring (SHM) has become increasingly important because of the need to know the remaining life of structures1-3. Nowadays, difficult to access locations, such as offshore wind plants, lead to higher risks in maintenance operations, as well as greater costs2-4. Self-sensing materials constitute one of the possibilities in the field of SHM due to their ability of self-monitoring strain and damage5.
In the case of wind turbines, blades are generally manufactured in glass fiber/epoxy composite materials, which are electrically insulators. In order to confer self-sensing properties to this composite material, an intrinsic electrical network susceptible to strain and damage needs to be created. During the last few years, the incorporation of conductive nanoparticles such as silver nanowires6,7, carbon nanotubes (CNTs)8-10, and graphene nanoplatelets (GNPs)11-13 has been studied to create this electrical network. These nanoparticles can be incorporated into the system as filler into the polymer matrix or by coating the glass fiber fabric14. These materials can be also applied to other industrial fields, i.e., aerospace, automotive and civil engineering5, and coated fabrics can be used as smart materials in biomechanical applications7,15.
Piezoresistivity of these sensors is achieved by three different contributions. The first contribution is the intrinsic piezoresistivity of the nanoparticles; a strain of the structure changes the electrical conductivity of the nanoparticles. However, the main contributions are changes in tunnel electrical resistance, due to modifications in distances between adjacent nanoparticles, and electrical contact resistance, because of variations in the contact area between overlying ones9. This piezoresistivity is higher when 2D nanoparticles are used as a nanofiller compared to 1D nanoparticles because the electrical network presents a higher susceptibility to geometrical changes and discontinuities, usually one order of magnitude superior16.
Due to the 2D atomic character17 and the high electrical conductivity18,19, graphene nanoplatelets have been selected in this work as the nano-reinforcer of multiscale composite materials in order to obtain self-sensors with enhanced sensitivity. Two different ways to incorporate the GNPs into the composite material are studied in order to elucidate possible differences in sensing mechanisms and sensitivity.

<table border="0" cellpadding="0" cellspacing="0" width="816">
	<colgroup>
		<col />
		<col />
		<col />
		<col />
	</colgroup>
	<tbody>
		<tr height="22">
			<td height="22" style="height:22px;width:217px;">Graphene Nanoplatelets</td>
			<td style="width:113px;">XGScience</td>
			<td style="width:319px;">M25</td>
			<td style="width:167px;">NA</td>
		</tr>
		<tr height="21">
			<td height="42" rowspan="2" style="height:42px;width:217px;">Epoxy resin&#160;</td>
			<td rowspan="2" style="width:113px;">Huntsman</td>
			<td style="width:319px;">Araldite LY556</td>
			<td>NA</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:319px;">XB3473</td>
			<td>NA</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:217px;">Probe sonication</td>
			<td>Hielscher&#160;</td>
			<td>UP400S&#160;</td>
			<td>NA</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:217px;">Three roll mill</td>
			<td style="width:113px;">Exakt</td>
			<td>Exakt 80E (Exakt GmbH)</td>
			<td>NA</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:217px;">Glass fiber fabric</td>
			<td style="width:113px;">Hexcel</td>
			<td>HexForce &#174; 01031 1000 TF970 E UD 4H&#160;</td>
			<td>NA</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:217px;">Hot plate press</td>
			<td style="width:113px;">Fontijne&#160;</td>
			<td>Fontijne LabEcon300</td>
			<td>NA</td>
		</tr>
		<tr height="22">
			<td height="22" style="height:22px;width:217px;">Sizing</td>
			<td style="width:113px;">Nanocyl</td>
			<td>SizicylTM</td>
			<td>NA</td>
		</tr>
		<tr height="22">
			<td height="22" style="height:22px;width:217px;">Multimeter</td>
			<td style="width:113px;">Alava Ingenieros</td>
			<td>Agilent 34410A&#160;</td>
			<td>NA</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:217px;">Strain Gauges</td>
			<td style="width:113px;">Vishay</td>
			<td>Micro-Measurement (MM&#174;) CEA-06-187UW-120&#160;</td>
			<td>NA</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:217px;">Mechanical tests machine</td>
			<td style="width:113px;">Zwick</td>
			<td>Zwick/Roell 100&#160;kN</td>
			<td>NA</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:217px;">Conductive silver paint</td>
			<td style="width:113px;">Monocomp</td>
			<td style="width:319px;">16062 &#8211; PELCO&#174; Conductive Silver Paint</td>
			<td>NA</td>
		</tr>
	</tbody>
</table>

strain sensing based on multiscale composite materials reinforced with graphene nanoplatelets

The electrical response of NH2-functionalized graphene nanoplatelets composite materials under strain was studied. Two different manufacturing methods are proposed to create the electrical network in this work: (a) the incorporation of the nanoplatelets into the epoxy matrix and (b) the coating of the glass fabric with a sizing filled with the same nanoplatelets. Both types of multiscale composite materials, with an in-plane electrical conductivity of ~10-3 S/m, showed an exponential growth of the electrical resistance as the strain increases due to distancing between adjacent functionalized graphene nanoplatelets and contact loss between overlying ones. The sensitivity of the materials analyzed during this research, using the described procedures, has been shown to be higher than commercially available strain gauges. The proposed procedures for self-sensing of the structural composite material would facilitate the structural health monitoring of components in difficult to access emplacements such as offshore wind power farms. Although the sensitivity of the multiscale composite materials was considerably higher than the sensitivity of metallic foils used as strain gauges, the value reached with NH2 functionalized graphene nanoplatelets coated fabrics was nearly an order of magnitude superior. This result elucidated their potential to be used as smart fabrics to monitor human movements such as bending of fingers or knees. By using the proposed method, the smart fabric could immediately detect the bending and recover instantly. This fact permits precise monitoring of the time of bending as well as the degree of bending.

The protocol to obtain two different materials has been described in the procedure. The difference is in the way the nanoreinforcement is incorporated in the composite material to achieve an electrical network that could be used to strain monitoring. The first method consists of the coating of a glass fiber fabric with f-GNP sizing that can be used as a smart fabric (named f-GNP/glass fiber) or as reinforcement of polymer matrix multiscale composite materials (named f-GNP/glass fiber comp...

Watch this Scientific Journal Video about Strain Sensing Based on Multiscale Composite Materials Reinforced with Graphene Nanoplatelets at JoVE.com

Strain Sensing Based on Multiscale Composite Materials Reinforced with Graphene Nanoplatelets

The integration of conductive nanoparticles, such as graphene nanoplatelets, into glass fiber composite materials creates an intrinsic electrical network susceptible to strain. Here, different methods to obtain strain sensors based on the addition of graphene nanoplatelets into the epoxy matrix or as a coating on glass fabrics are proposed.

The electrical response of NH2-functionalized graphene nanoplatelets composite materials under strain was studied. Two different manufacturing methods are ...

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In Situ Transmission Electron Microscopy with Biasing and Fabrication of Asymmetric Crossbars Based on Mixed-Phased a-VOx

In Situ Transmission Electron Microscopy with Biasing and Fabrication of Asymmetric Crossbars Based on Mixed-Phased a-VOx

혼합 위상 a-VOx에 따라 비대칭 크로스바의 바이어스 및 제조와 시투 전송 전자 현미경 검사법

Resistive switching crossbar architecture is highly desired in the field of digital memories due to low cost and high-density benefits. Different ...

Advanced Self-Healing Asphalt Reinforced by Graphene Structures: An Atomistic Insight

그래핀 구조에 의해 강화 된 고급 자기 치유 아스팔트 : 원자 론적 통찰력

Graphene can improve the self-healing properties of asphalt with high durability. However, the self-healing behaviors of graphene-modified asphalt ...