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Graphene has attracted enormous attention due to its extraordinary physical properties, which have potential for increasing the thermal conductivity of nanocomposites or nanofluids, and the thermal resistance between graphene and the surrounding matrices arises as an important issue. In this paper, the thermal transport at the graphene-water interface is investigated by molecular dynamics simulations. The interfacial thermal resistance decreases with the graphene layer number. Interlayer functionalization by oxygen atoms is applied to tune the interfacial thermal resistance. A peak thermal resistance reduction of nearly 50% is generated with the oxygen ratio of only 0.5% for two-layer graphene. Based on the analyses of vibrational density of states, it is found that lower thermal resistance is consistent with more vibrational density of states overlaps at the interface. Our results are instructive for improving the interfacial thermal transport in graphene-based nanocomposites and nanofluids.

Objective 68Ga-DOTATATE PET/CT is currently the most common imaging modality in localizing culprit tumors, which can result in tumor-induced osteomalacia (TIO). Fracture, which is one of the most common consequences of the TIO, can also lead to increased 68Ga-DOTATATE activity and potentially affect the accuracy of 68Ga-DOTATATE PET/CT imaging. The aim of this investigation is to evaluate whether the increased 68Ga-DOTATATE activity at the sites of the fracture will cause interpretation difficulty in the localizing the culprit tumor causing TIO. Method The images of 68Ga-DOTATATE PET/CT scan from a total of 54 patients who had multiple foci of increased 68Ga-DOTATATE PET/CT on PET/CT were retrospectively analyzed. Not only was the intensity of the activity on PET but also the appearance of the activity on CT taken into consideration when the interpretation of the images occurred. The results from imaging analysis were compared with the clinical chart record. All patients had tentative clinical diagnosis of TIO. Results The causative tumors in 53 patients were eventually identified. In 1 patient, the causative tumor was not identified. Among the 53 patients with confirmed TIO, 52 tumors were accurately localized. Conclusions Mild activity at the sites of fracture is not a major challenging factor in the interpretation of 68Ga-DOTATATE PET/CT in the evaluation of TIO when both intensity on PET and morphology on CT were assessed.

A nonequilibrium molecular dynamics (MD) method is used to calculate the thermal resistance between crossed carbon nanotubes (CNTs). The thermal resistance is predicted to be of the order of 10 9-10 11 K/W. The effects of the crossing angle, nanotube length, and initial nanotube spacing on the thermal resistance are studied in detail with the fixed boundary condition applied in the axial direction of each CNT. The thermal resistance is found to increase with the increasing crossing angle while decrease with the increasing nanotube length and converge to a constant eventually. An increase in the thermal resistance is observed for nanotubes with larger initial spacing and the increase becomes abrupt as the initial spacing is increased to the van der Waals diameter. Between the crossed CNTs the phonon transport is constricted through the contact. The thermal resistance between the crossed CNTs calculated by MD is found to be close to the ballistic constriction resistance, which indicates that the constriction thermal resistance plays a major role in the inter-tube thermal resistance and the ballistic transport of phonons is dominant in the thermal transport between the crossed CNTs. V

We investigate current rectification in diblock co-oligomer diode molecules on the basis of the Su-Schrieffer-Heeger model [Phys. Rev. B 22, 2099 (1980)] combined with the nonequilibrium Green’s function formalism. The current rectification observed in experiment [M. K. Ng et al., J. Am. Chem. Soc 124, 11862 (2002)] is well explained by the mechanism of bias-induced asymmetric hybridization of molecular orbitals. The positive bias tends to delocalize molecular orbitals through the hybridization, which produces a sharp increase in current at the threshold voltage; while the negative bias enhances the mismatch of energy levels and has no effect on the hybridization and the current.

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The spontaneous capillarity-driven flow behaviors of PE melts through AAO nanopores suggest that the zero-shear-rate viscosity of the PE melts decreases, which can be predicted by a modified Lucas–Washburn law considering the polymer rheological model.

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