Peidong Yang

Bio: Peidong Yang is an academic researcher from University of California, Berkeley. The author has contributed to research in topics: Nanowire & Perovskite (structure). The author has an hindex of 183, co-authored 562 publications receiving 144351 citations. Previous affiliations of Peidong Yang include Max Planck Society & University of California, Santa Barbara.

Atomic Structure of Pt3Ni Nanoframe Electrocatalysts by in Situ X-ray Absorption Spectroscopy.

Abstract: Understanding the atomic structure of a catalyst is crucial to exposing the source of its performance characteristics. It is highly unlikely that a catalyst remains the same under reaction conditions when compared to as-synthesized. Hence, the ideal experiment to study the catalyst structure should be performed in situ. Here, we use X-ray absorption spectroscopy (XAS) as an in situ technique to study Pt3Ni nanoframe particles which have been proven to be an excellent electrocatalyst for the oxygen reduction reaction (ORR). The surface characteristics of the nanoframes were probed through electrochemical hydrogen underpotential deposition and carbon monoxide electrooxidation, which showed that nanoframe surfaces with different structure exhibit varying levels of binding strength to adsorbate molecules. It is well-known that Pt-skin formation on Pt–Ni catalysts will enhance ORR activity by weakening the binding energy between the surface and adsorbates. Ex situ and in situ XAS results reveal that nanoframes...

SnO2 Nanoribbons as NO2 Sensors: Insights from First Principles Calculations

Abstract: SnO2 nanoribbons with exposed (1 0 1) and (0 1 0) surfaces have recently been demonstrated to be highly effective NO2 sensors even at room temperature. The sensing mechanism is examined here through first principles density functional theory (DFT) calculations. We show that the most stable adsorbed species involve an unexpected NO3 group doubly bonded to Sn centers. Significant electron transfer to the adatoms explains an orders-of-magnitude drop in electrical conductance. X-ray absorption spectroscopy indicates predominantly NO3 species on the surface, and computed binding energies are consistent with adsorbate stability up to 700 K. Nanoribbon responses to O2 and CO sensing are also investigated.

Si Nanowire Bridges in Microtrenches: Integration of Growth into Device Fabrication

Abstract: The precursor formamide 1 was employed instead of the monomer 2 because isocyanides are relatively unstable in air at room temperature. [19] a) [20] Molecular modeling shows that (in common with the phenyl benzo-ate compounds previously described [17]) an angle exists between the planar phenoxy and TTF ring systems. [21] The oxidation of the polymer was performed in a mixture of solvents to ensure solubility of reagents and products throughout the process. The CD spectra of the polymer in THF and in CH 2 Cl 2 are essentially identical, but the Cotton effects observed in CH 2 Cl 2 :MeCN 7:3 are somewhat different, presumably owing to aggregation, as seen in other polymeric systems. See a) B.1 mol of TTF unit, taking the molecular weight of the monomer. The Fe III salt was spectrophotometri-cally titrated as ferric acetate in water prior to use; see: D. [23] For references on calculated and experimental UV-vis absorption of cation radicals and dications of TTF derivatives, see: a) Silicon nanowires are attractive building blocks for nano-scale electronic systems due to their compatibility with existing semiconductor technology. Studies have focused on their synthesis, [1±5] with considerable advances made in the control of structures, [6] electrical, [7,8] and thermal [9] properties. For practical applications, different strategies have been explored to fabricate nanowire-based devices. The pick-and-place approach [7,8,9] has succeeded in making individual devices such

Dopant profiling and surface analysis of silicon nanowires using capacitance-voltage measurements

Abstract: Silicon nanowires could be central components in electronic and thermoelectric devices, but understanding nanowire surface properties and dopant distribution will be essential for making reproducible high-performance devices. Present methods for determining these parameters are problematic. Now, by using capacitance-voltage analysis, the radial profile and interface state density of silicon-nanowire field-effect transistors have been measured.

Fast parallel algorithms for short-range molecular dynamics

Abstract: Three parallel algorithms for classical molecular dynamics are presented. The first assigns each processor a fixed subset of atoms; the second assigns each a fixed subset of inter-atomic forces to compute; the third assigns each a fixed spatial region. The algorithms are suitable for molecular dynamics models which can be difficult to parallelize efficiently—those with short-range forces where the neighbors of each atom change rapidly. They can be implemented on any distributed-memory parallel machine which allows for message-passing of data between independently executing processors. The algorithms are tested on a standard Lennard-Jones benchmark problem for system sizes ranging from 500 to 100,000,000 atoms on several parallel supercomputers--the nCUBE 2, Intel iPSC/860 and Paragon, and Cray T3D. Comparing the results to the fastest reported vectorized Cray Y-MP and C90 algorithm shows that the current generation of parallel machines is competitive with conventional vector supercomputers even for small problems. For large problems, the spatial algorithm achieves parallel efficiencies of 90% and a 1840-node Intel Paragon performs up to 165 faster than a single Cray C9O processor. Trade-offs between the three algorithms and guidelines for adapting them to more complex molecular dynamics simulations are also discussed.

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

Abstract: 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。

Electronics and optoelectronics of two-dimensional transition metal dichalcogenides.

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

A comprehensive review of zno materials and devices

Abstract: The semiconductor ZnO has gained substantial interest in the research community in part because of its large exciton binding energy (60meV) which could lead to lasing action based on exciton recombination even above room temperature. Even though research focusing on ZnO goes back many decades, the renewed interest is fueled by availability of high-quality substrates and reports of p-type conduction and ferromagnetic behavior when doped with transitions metals, both of which remain controversial. It is this renewed interest in ZnO which forms the basis of this review. As mentioned already, ZnO is not new to the semiconductor field, with studies of its lattice parameter dating back to 1935 by Bunn [Proc. Phys. Soc. London 47, 836 (1935)], studies of its vibrational properties with Raman scattering in 1966 by Damen et al. [Phys. Rev. 142, 570 (1966)], detailed optical studies in 1954 by Mollwo [Z. Angew. Phys. 6, 257 (1954)], and its growth by chemical-vapor transport in 1970 by Galli and Coker [Appl. Phys. ...