Yu Huang

Bio: Yu Huang is an academic researcher from Chinese Academy of Sciences. The author has contributed to research in topics: Medicine & Materials science. The author has an hindex of 136, co-authored 1492 publications receiving 89209 citations. Previous affiliations of Yu Huang include The Chinese University of Hong Kong & Samsung.

Fabrication and electrical properties of graphene nanoribbons

Abstract: Graphene is a semimetal with a zero band gap, and therefore cannot be used for effective field-effect transistors (FETs) at room temperature. Theoretical study predicted an appreciable band gap opening with the formation of nanometer graphene nanoribbons (GNRs), providing opportunities for graphene based transistor application. In this paper, we review recent developments in fabrication and electrical property studies of GNRs. We first study the theoretic prediction of electrical structures in ideal graphene nanoribbons which is closely related to the edge configurations. Different experimental efforts to fabricate GNRs are introduced and the electrical transport behaviors of fabricated GNR device are described. We then investigate the effect of edge disorder and charge impurities on real device performance, in which Anderson localization and Coulomb blockade effect are discussed to explain the observed transport behaviors. Other approaches such as symmetry broken to induce band gap on bulk graphene are also described.

Distribution, depletion and recovery of docosahexaenoic acid are region-specific in rat brain.

Abstract: The present study examined: (i) age-induced regional changes in fatty acid composition of brain phospholipids; (ii) alpha-linolenic acid deficiency-induced regional depletion and recovery of DHA in the brain. DHA and arachidonic acid (AA) did not distribute evenly in the brain. In weaning and adult rats, the region with the highest DHA percentage was the cortex whereas the medulla had the lowest DHA percentage. In the aged rats, both the cortex and cerebellum were the regions with the highest DHA percentage whereas in the neonatal rats, the striatum had the greatest percentage of DHA, and the hypothalamus and hippocampus had the least percentage of DHA. Regarding AA, the hippocampus was the region that had the highest percentage whereas the medulla was the region with the lowest percentage except for the neonatal rats, whose cerebellum, hypothalamus, striatum and midbrain had AA percentage lower than hippocampus and cortex. DHA was not proportionally depleted in various regions of brain when the rats were maintained on an n-3-deficient diet for two generations. The results demonstrated that the cortex, hippocampus, striatum, cerebellum and hypothalamus had DHA depleted by >71 %, whereas the midbrain and medulla had only 64 and 57 % DHA depleted, respectively. The most important observation was that the diet reversal for 12 weeks resulted in complete DHA recovery in all regions except for the medulla where the recovery was only 62 %. It was concluded that the location of DHA, n-3 deficiency-induced DHA depletion and reversibility of DHA deficiency across the brain were region-specific.

In Situ Transmission Electron Microscopy for Energy Materials and Devices.

Abstract: Energy devices such as rechargeable batteries, fuel cells, and solar cells are central to powering a renewable, mobile, and electrified future. To advance these devices requires a fundamental understanding of the complex chemical reactions, material transformations, and charge flow that are associated with energy conversion processes. Analytical in situ transmission electron microscopy (TEM) offers a powerful tool for directly visualizing these complex processes at the atomic scale in real time and in operando. Recent advancements in energy materials and devices that have been enabled by in situ TEM are reviewed. First, the evolutionary development of TEM nanocells from the open-cell configuration to the closed-cell, and finally the full-cell, is reviewed. Next, in situ TEM studies of rechargeable ion batteries in a practical operation environment are explored, followed by applications of in situ TEM for direct observation of electrocatalyst formation, evolution, and degradation in proton-exchange membrane fuel cells, and fundamental investigations of new energy materials such as perovskites for solar cells. Finally, recent advances in the use of environmental TEM and cryogenic electron microscopy in probing clean-energy materials are presented and emerging opportunities and challenges in in situ TEM research of energy materials and devices are discussed.

Advanced Space-based Solar Observatory (ASO-S): an overview

Abstract: The Advanced Space-based Solar Observatory (ASO-S) is a mission proposed for the 25th solar maximum by the Chinese solar community. The scientific objectives are to study the relationships between the solar magnetic field, solar flares and coronal mass ejections (CMEs). Three payloads are deployed: the Full-disk vector MagnetoGraph (FMG), the Lyman-alpha Solar Telescope (LST) and the Hard X-ray Imager (HXI). ASO-S will perform the first simultaneous observations of the photospheric vector magnetic field, non-thermal imaging of solar flares, and the initiation and early propagation of CMEs on a single platform. ASO-S is scheduled to be launched into a 720 km Sun-synchronous orbit in 2022. This paper presents an overview of the mission till the end of Phase-B and the beginning of Phase-C.

I and i

Abstract: There is, I think, something ethereal about i —the square root of minus one. I remember first hearing about it at school. It seemed an odd beast at that time—an intruder hovering on the edge of reality. Usually familiarity dulls this sense of the bizarre, but in the case of i it was the reverse: over the years the sense of its surreal nature intensified. It seemed that it was impossible to write mathematics that described the real world in …

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。