Analyzing fine scaling quantum effects on the buckling of axially-loaded carbon nanotubes based on the density functional theory and molecular mechanics method.

In this paper, the quantum effects of fine scaling on the buckling behavior of carbon nanotubes (CNTs) under axial loading are investigated. Molecular mechanics and quantum mechanics are respectively utilized to study the buckling behavior and to obtain the molecular mechanics coefficients of fine-scale nanotubes. The results of buckling behavior of CNTs with different chiralities with finite and infinite dimensions are given, and a comparison study is presented on them.

Torsional buckling analysis of MWCNTs considering quantum effects of fine scaling based on DFT and molecular mechanics method.

In this paper, quantum and molecular mechanics are used to study the quantum effects of fine scaling on the buckling strength of multi-walled carbon nanotubes (MWCNTs), as well as the effects of changes in length, diameter, chirality, wall number and length-to-diameter ratio of the structure under torsional loading. To this end, the total potential energy of the system is calculated with the consideration of both bond stretching and bond angular variations. The density functional theory (DFT) along with the generalized gradient approximation (GGA) function is used to obtain the relevant elastic constants of the nanotubes.

Identification and characterization of metabolite quantitative trait loci in tomato leaves and comparison with those reported for fruits and seeds.

Introduction: To date, most studies of natural variation and metabolite quantitative trait loci (mQTL) in tomato have focused on fruit metabolism, leaving aside the identification of genomic regions involved in the regulation of leaf metabolism.

Objective: This study was conducted to identify leaf mQTL in tomato and to assess the association of leaf metabolites and physiological traits with the metabolite levels from other tissues.

Methods: The analysis of components of leaf metabolism was performed by phenotypying 76 tomato ILs with chromosome segments of the wild species Solanum pennellii in the genetic background of a cultivated tomato (S.

Mechanical properties of chiral and achiral silicon carbide nanotubes under oxygen chemisorption.

In this paper, the mechanical properties of fully oxygenated silicon carbide nanotubes (O2-SiCNTs) are explored using a molecular mechanics model joined with the density functional theory (DFT). The closed-form analytical expressions suggested in this study can easily be adapted for nanotubes with different chiralities. The force constants of molecular mechanics model proposed herein are derived through DFT within a generalized gradient approximation.

Variation in genetics and performance of Dutch western flower thrips populations.

Invasion of pests may result in local adaptation and the development of biotypes specialized in different hosts. In this study, we investigated western flower thrips, Frankliniella occidentalis (Pergande), an invasive pest in Europe. Thrips from different commercial glasshouse crops within the Dutch Westland and a lab culture kept on chrysanthemum were compared.