다중혈관 관상동맥 환자에서 y-문합을 이용하여 양쪽 내흉동맥만을 사용한 우회술의 조기 성적

This article reviews the basic theoretical aspects of graphene, a one-atom-thick allotrope of carbon, with unusual two-dimensional Dirac-like electronic excitations. The Dirac electrons can be controlled by application of external electric and magnetic fields, or by altering sample geometry and/or topology. The Dirac electrons behave in unusual ways in tunneling, confinement, and the integer quantum Hall effect. The electronic properties of graphene stacks are discussed and vary with stacking order and number of layers. Edge (surface) states in graphene depend on the edge termination (zigzag or armchair) and affect the physical properties of nanoribbons. Different types of disorder modify the Dirac equation leading to unusual spectroscopic and transport properties. The effects of electron-electron and electron-phonon interactions in single layer and multilayer graphene are also presented.

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The electronic properties of graphene

抗原变异可使得多种致病微生物易于逃避宿主免疫应答。表达在感染红细胞表面的恶性疟原虫红细胞表面蛋白1（PfPMP1）与感染红细胞、内皮细胞、树突状细胞以及胎盘的单个或多个受体作用，在黏附及免疫逃避中起关键的作用。每个单倍体基因组var基因家族编码约60种成员，通过启动转录不同的var基因变异体为抗原变异提供了分子基础。

疟原虫var基因转换速率变化导致抗原变异[英]／Paul H, Robert P, Christodoulou Z, et al//Proc Natl Acad Sci U S A

Single-layer metal dichalcogenides are two-dimensional semiconductors that present strong potential for electronic and sensing applications complementary to that of graphene.

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Electronics and optoelectronics of two-dimensional transition metal dichalcogenides.

[신간의 별자리x] 우리/미술, 그리고 ‘슬픔의 박물관’

Thin (6–7 quintuple layer) topological insulator Bi2Se3 quantum dot devices are demonstrated using ultrathin (2–4 quintuple layer) Bi2Se3 regions to realize semiconducting barriers which may be tuned from ohmic to tunneling conduction via gate voltage. Transport spectroscopy shows Coulomb blockade with large charging energy >5 meV and additional features implying excited states.

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Topological insulator quantum dot with tunable barriers.

Thin membranes exhibit complex responses to external forces or geometrical constraints. A familiar example is the wrinkling, exhibited by human skin, plant leaves, and fabrics, resulting from the relative ease of bending versus stretching. Here, we study the wrinkling of graphene, the thinnest and stiffest known membrane, deposited on a silica substrate decorated with silica nanoparticles. At small nanoparticle density monolayer graphene adheres to the substrate, detached only in small regions around the nanoparticles. With increasing nanoparticle density, we observe the formation of wrinkles which connect nanoparticles. Above a critical nanoparticle density, the wrinkles form a percolating network through the sample. As the graphene membrane is made thicker, global delamination from the substrate is observed. The observations can be well understood within a continuum elastic model and have important implications for strain-engineering the electronic properties of graphene.

Princess and the Pea at the nanoscale: Wrinkling and delamination of graphene on nanoparticles

http://www.physics.umd.edu/mfuhrer/publications/OrganicElectronicsSouthardSWNTelectrodes.pdf

Solution-processed single walled carbon nanotube electrodes for organic thin-film transistors

The temperature dependence of $1∕f$ noise in individual semiconducting carbon nanotube (CNT) field-effect transistors is used to estimate the distribution of activation energies of the fluctuators $D(E)$ responsible for the noise. $D(E)$ shows a rise at low energy with no characteristic energy scale, and a broad peak at $\ensuremath{\sim}0.4\phantom{\rule{0.3em}{0ex}}\mathrm{eV}$. The peak, responsible for the majority of noise at room temperature, cannot be due to electronic excitations, carrier number fluctuations, or structural fluctuations of the CNT, and likely results from the motion of defects in the dielectric or at the CNT-dielectric interface, or very strongly physisorbed species (binding energy $\ensuremath{\sim}0.4\phantom{\rule{0.3em}{0ex}}\mathrm{eV}$) on the CNT or dielectric surface.

Origins of 1 ∕ f noise in individual semiconducting carbon nanotube field-effect transistors

THE mechanism of superconductivity in alkali-metal compounds of C6o (refs 1, 2) remains controversial. Electron-pairing mechanisms based on electron-phonon coupling involving both low-frequency (intermolecular) vibrations3 and high-frequency (intramolecular) modes4,5—the strong-coupling and weak-coupling cases respectively—have been proposed. These two mechanisms have different associated energy scales, which is reflected in the magnitude of the superconducting energy gap. Measurements of the gap for these compounds have been reported previously for powder samples6–8, but are somewhat discrepant or ambiguous, perhaps owing to grain-size or grain-junction effects. Here we report measurements on large single-crystal samples of K3C60 and Rb3C60 using optical reflectivity. We obtain values for the reduced gap ratio, 2Δ/k8Tc of 3.44 and 3.45 respectively, consistent with predictions for a mechanism based on standard Bardeen-Cooper-Schrieffer (BCS) electron-phonon coupling to intramolecular modes.

Michael S. Fuhrer

Papers

Topological insulator quantum dot with tunable barriers.

Princess and the Pea at the nanoscale: Wrinkling and delamination of graphene on nanoparticles

Solution-processed single walled carbon nanotube electrodes for organic thin-film transistors

Origins of 1 ∕ f noise in individual semiconducting carbon nanotube field-effect transistors

Optical measurements of the superconducting gap in single-crystal K3C60 and Rb3C60