Yang Yang

Bio: Yang Yang is an academic researcher from Chinese Academy of Sciences. The author has contributed to research in topics: Medicine & Computer science. The author has an hindex of 171, co-authored 2644 publications receiving 153049 citations. Previous affiliations of Yang Yang include Zhejiang University & Northwest Normal University.

Relating Recombination, Density of States, and Device Performance in an Efficient Polymer:Fullerene Organic Solar Cell Blend

Abstract: We explore the interrelation between density of states, recombination kinetics, and device performance in effi cient poly(4,8-bis-(2-ethylhexyloxy)- benzo(1,2-b:4,5-b')dithiophene-2,6-diyl-alt-4-(2-ethylhexyloxy-1-one) thieno(3,4-b)thiophene-2,6-diyl):(6,6)-phenyl-C 71 -butyric acid methyl ester (PBDTTT-C:PC 71 BM) bulk-heterojunction organic solar cells. We modulate the active-layer density of states by varying the polymer:fullerene com- position over a small range around the ratio that leads to the maximum solar cell effi ciency (50-67 wt% PC 71 BM). Using transient and steady-state techniques, we fithat nongeminate recombination limits the device effi - ciency and, moreover, that increasing the PC 71 BM content simultaneously increases the carrier lifetime and drift mobility in contrast to the behavior expected for Langevin recombination. Changes in electronic properties with fullerene content are accompanied by a signifi cant change in the magnitude or energetic separation of the density of localized states. Our comprehensive approach to understanding device performance represents signifi cant progress in understanding what limits these high-effi ciency polymer:fullerene systems.

Low temperature silicon dioxide by thermal atomic layer deposition: Investigation of material properties

Abstract: SiO2 is the most widely used dielectric material but its growth or deposition involves high thermal budgets or suffers from shadowing effects. The low-temperature method presented here (150 °C) for the preparation of SiO2 by thermal atomic layer deposition (ALD) provides perfect uniformity and surface coverage even into nanoscale pores, which may well suit recent demands in nanoelectronics and nanotechnology. The ALD reaction based on 3-aminopropyltriethoxysilane, water, and ozone provides outstanding SiO2 quality and is free of catalysts or corrosive by-products. A variety of optical, structural, and electrical properties are investigated by means of infrared spectroscopy, UV-Vis spectroscopy, secondary ion mass spectrometry, capacitance-voltage and current-voltage measurements, electron spin resonance, Rutherford backscattering, elastic recoil detection analysis, atomic force microscopy, and variable angle spectroscopic ellipsometry. Many features, such as the optical constants (n, k) and optical transm...

Controlled Electrodeposition Synthesis of Co–Ni–P Film as a Flexible and Inexpensive Electrode for Efficient Overall Water Splitting

Abstract: Synthesis of highly efficient and robust catalysts with earth-abundant resources for overall water splitting is essential for large-scale energy conversion processes. Herein, a series of highly active and inexpensive Co–Ni–P films were fabricated by a one-step constant current density electrodeposition method. These films were demonstrated to be efficient bifunctional catalysts for both H2 and O2 evolution reactions (HER and OER), while deposition time was deemed to be the crucial factor governing electrochemical performance. At the optimal deposition time, the obtained Co–Ni–P-2 catalyst performed remarkably for both HER and OER in alkaline media. In particular, it requires −103 mV overpotential for HER and 340 mV for OER to achieve the current density of 10 mA cm–2, with corresponding Tafel slopes of 33 and 67 mV dec–1. Moreover, it outperforms the Pt/C//RuO2 catalyst and only needs −160 mV (430 mV) overpotential for HER (OER) to achieve 200 mA cm–2 current density. Co–Ni–P electrodes were also conducte...

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。

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.