By employing the nonlinear von Karman shell theory and the theory of piezoelect ricity including thermal effec ts,the constitutive relations of the BNNT-reinforced piezoelec trie shell are built.Recurring to the'X...By employing the nonlinear von Karman shell theory and the theory of piezoelect ricity including thermal effec ts,the constitutive relations of the BNNT-reinforced piezoelec trie shell are built.Recurring to the'XY‘rec tangle model,the material consta nts are reckoned.Then,the nonlinear governing equations of the st rue ture are derived t hrough the Reissner variational principle and solved by the fourth-order Runge-Kutta method.In numerical calculations,the effects of temperature,voltage,volume fraction,etc.,on the bifurcation and chaos of piezoelectric shell reinforced with BNNTs are discussed in detail.展开更多
By means of density functional theory calculations, an orthogonal boron-carbon-nitrogen compound called （3,0）- BC2N is predicted, which can be obtained by transversely compressing （3,03 carbon nanotubes （CNTs） an...By means of density functional theory calculations, an orthogonal boron-carbon-nitrogen compound called （3,0）- BC2N is predicted, which can be obtained by transversely compressing （3,03 carbon nanotubes （CNTs） and boron nitride nanotubes （BNNTs）. Its structural stability, elastic properties, mechanical properties and electronic structure are systematically investigated. The results show that （3,0）-BU2N is a superhard material with a direct bandgap. However, its similar structures, （3,0）-C and （3,0）-BN are indirect semiconductors. Strikingly, （3,0）-C is harder than diamond. We also simulate the x-ray diffraction of （3,0）-BC2N to support future experimental investigations. In addition, our study shows that the transition from （3,03 CNTS and BNNTs to （3,0）-BC2N is irreversible.展开更多
Under combined electro-thermo-mechanical loadings, the nonlinear bending of piezoelectric cylindrical shell reinforced with boron nitride nanotubes (BNNTs) is investigated in this paper. By employing nonlinear strains...Under combined electro-thermo-mechanical loadings, the nonlinear bending of piezoelectric cylindrical shell reinforced with boron nitride nanotubes (BNNTs) is investigated in this paper. By employing nonlinear strains based on Donnell shell theory and utilizing piezoelectric theory including thermal effects, the constitutive relations of the piezoelectric shell reinforced with BNNTs are established. Then the governing equations of the structure are derived through variational principle and resolved by applying the finite difference method. In numerical examples, the effects of geometric nonlinear, voltage, temperature, as well as volume fraction on the deflection and bending moment of axisymmetrical piezoelectric cylindrical shell reinforced with BNNTs are discussed in detail.展开更多
A thin BN interphase is applied on BNNTs surface to tailor the interfacial bonding between BNNTs and SiC matrix in hierarchical SiCf/SiC composites. The thickness of BN interphase ranging from 10 to 70 nm can be optim...A thin BN interphase is applied on BNNTs surface to tailor the interfacial bonding between BNNTs and SiC matrix in hierarchical SiCf/SiC composites. The thickness of BN interphase ranging from 10 to 70 nm can be optimized by chemical vapor deposition after BNNTs are in situ grown on SiC fiber surface. Without BN interphase, the fracture toughness of hierarchical Si Cf/Si C composites can be impaired by 13.6% due to strong interfacial bonding. As long as BN interphase with 30–45 nm thickness is applied, the interfacial bonding can be optimized and fracture toughness of hierarchical composites can be improved by 27.3%. It implies that tailoring BNNTs/matrix interface by depositing a layer of BN interphase is in favor of activating energy dissipation mechanisms at nanoscale induced by BNNTs.展开更多
In this research,a density functional theory(DFT)calculation was performed for investigation adsorption behavior of the anticancer drug Vemurafenib on BNNT(5,5-9)by using the M06-2X/6-31 G*level of theory in the solve...In this research,a density functional theory(DFT)calculation was performed for investigation adsorption behavior of the anticancer drug Vemurafenib on BNNT(5,5-9)by using the M06-2X/6-31 G*level of theory in the solvent water.The electronic spectra of the Vemurafenib drug,BNNT(5,5-9)and complex BNNT(5,5-9)/Vemurafenib in solvent water were calculated by Time Dependent Density Functional Theory(TD-DFT)for the study of adsorption effect.The non-bonded interaction effects of the Vemurafenib drug with BNNT(5,5-9)on the electronic properties,natural charges and chemical shift tensors have been also detected.The results display the change in title parameters after process adsorption.According to the natural bond orbital(NBO)results,the molecule Vemurafenib and BNNT(5,5-9)play as both electron donor and acceptor at the complex BNNT(5,5-9)/Vemurafenib.On the other hand,the charge transfer occurs between the bonding,antibonding or nonbonding orbitals in two molecules drug and BNNT.As a consequence,BNNT(5,5-9)can be considered as a drug delivery system for the transportation of Vemurafenib as anticancer drug within the biological systems.展开更多
基金the supports from National Natural Science Foundation of China(Project No.51822803).
文摘By employing the nonlinear von Karman shell theory and the theory of piezoelect ricity including thermal effec ts,the constitutive relations of the BNNT-reinforced piezoelec trie shell are built.Recurring to the'XY‘rec tangle model,the material consta nts are reckoned.Then,the nonlinear governing equations of the st rue ture are derived t hrough the Reissner variational principle and solved by the fourth-order Runge-Kutta method.In numerical calculations,the effects of temperature,voltage,volume fraction,etc.,on the bifurcation and chaos of piezoelectric shell reinforced with BNNTs are discussed in detail.
基金Supported by the National Natural Science Foundation of China under Grant No 11464028the Science Foundation of Department of Education of Jiangxi Province under Grant No GJJ150025
文摘By means of density functional theory calculations, an orthogonal boron-carbon-nitrogen compound called （3,0）- BC2N is predicted, which can be obtained by transversely compressing （3,03 carbon nanotubes （CNTs） and boron nitride nanotubes （BNNTs）. Its structural stability, elastic properties, mechanical properties and electronic structure are systematically investigated. The results show that （3,0）-BU2N is a superhard material with a direct bandgap. However, its similar structures, （3,0）-C and （3,0）-BN are indirect semiconductors. Strikingly, （3,0）-C is harder than diamond. We also simulate the x-ray diffraction of （3,0）-BC2N to support future experimental investigations. In addition, our study shows that the transition from （3,03 CNTS and BNNTs to （3,0）-BC2N is irreversible.
文摘Under combined electro-thermo-mechanical loadings, the nonlinear bending of piezoelectric cylindrical shell reinforced with boron nitride nanotubes (BNNTs) is investigated in this paper. By employing nonlinear strains based on Donnell shell theory and utilizing piezoelectric theory including thermal effects, the constitutive relations of the piezoelectric shell reinforced with BNNTs are established. Then the governing equations of the structure are derived through variational principle and resolved by applying the finite difference method. In numerical examples, the effects of geometric nonlinear, voltage, temperature, as well as volume fraction on the deflection and bending moment of axisymmetrical piezoelectric cylindrical shell reinforced with BNNTs are discussed in detail.
基金supported by National Natural Science Foundation of China (Grant Nos. 51772310 and 51502323)the National Key Research and Development Program of China (Grant No. 2017YFB0703200)+2 种基金the research grant from Science and Technology Commission of Shanghai Municipality (Grant No. 16DZ2260600)Science Foundation for Youth Scholar of State Key Laboratory of High Performance Ceramics (Grant No. SKL201601)Chinese Academy of Science (Grant No. QYZDY-SSW-JSC031).
文摘A thin BN interphase is applied on BNNTs surface to tailor the interfacial bonding between BNNTs and SiC matrix in hierarchical SiCf/SiC composites. The thickness of BN interphase ranging from 10 to 70 nm can be optimized by chemical vapor deposition after BNNTs are in situ grown on SiC fiber surface. Without BN interphase, the fracture toughness of hierarchical Si Cf/Si C composites can be impaired by 13.6% due to strong interfacial bonding. As long as BN interphase with 30–45 nm thickness is applied, the interfacial bonding can be optimized and fracture toughness of hierarchical composites can be improved by 27.3%. It implies that tailoring BNNTs/matrix interface by depositing a layer of BN interphase is in favor of activating energy dissipation mechanisms at nanoscale induced by BNNTs.
基金supported by the National Academy of Sciences of Belarus。
文摘In this research,a density functional theory(DFT)calculation was performed for investigation adsorption behavior of the anticancer drug Vemurafenib on BNNT(5,5-9)by using the M06-2X/6-31 G*level of theory in the solvent water.The electronic spectra of the Vemurafenib drug,BNNT(5,5-9)and complex BNNT(5,5-9)/Vemurafenib in solvent water were calculated by Time Dependent Density Functional Theory(TD-DFT)for the study of adsorption effect.The non-bonded interaction effects of the Vemurafenib drug with BNNT(5,5-9)on the electronic properties,natural charges and chemical shift tensors have been also detected.The results display the change in title parameters after process adsorption.According to the natural bond orbital(NBO)results,the molecule Vemurafenib and BNNT(5,5-9)play as both electron donor and acceptor at the complex BNNT(5,5-9)/Vemurafenib.On the other hand,the charge transfer occurs between the bonding,antibonding or nonbonding orbitals in two molecules drug and BNNT.As a consequence,BNNT(5,5-9)can be considered as a drug delivery system for the transportation of Vemurafenib as anticancer drug within the biological systems.
