Raman Spectral Band Oscillations in Large Graphene Bubbles

Huang, Yuan,Wang, Xiao,Zhang, Xu,Chen, Xianjue,Li, Baowen,Wang, Bin,Huang, Ming,Zhu, Chongyang,Zhang, Xuewei,Bacsa, Wolfgang S.,Ding, Feng,Ruoff, Rodney S. American Physical Society 2018 Physical Review Letters Vol.120 No.18

<P>Raman spectra of large graphene bubbles showed size-dependent oscillations in spectral intensity and frequency, which originate from optical standing waves formed in the vicinity of the graphene surface. At a high laser power, local heating can lead to oscillations in the Raman frequency and also create a temperature gradient in the bubble. Based on Raman data, the temperature distribution within the graphene bubble was calculated, and it is shown that the heating effect of the laser is reduced when moving from the center of a bubble to its edge. By studying graphene bubbles, both the thermal conductivity and chemical reactivity of graphene were assessed. When exposed to hydrogen plasma, areas with bubbles are found to be more reactive than flat graphene.</P>

Highly Oriented Monolayer Graphene Grown on a Cu/Ni(111) Alloy Foil

Huang, Ming,Biswal, Mandakini,Park, Hyo Ju,Jin, Sunghwan,Qu, Deshun,Hong, Seokmo,Zhu, Zhili,Qiu, Lu,Luo, Da,Liu, Xiaochi,Yang, Zheng,Liu, Zhongliu,Huang, Yuan,Lim, Hyunseob,Yoo, Won Jong,Ding, Feng,Wa American Chemical Society 2018 ACS NANO Vol.12 No.6

<P>Fast-growth of single crystal monolayer graphene by CVD using methane and hydrogen has been achieved on “homemade” single crystal Cu/Ni(111) alloy foils over large area. Full coverage was achieved in 5 min or less for a particular range of composition (1.3 at.% to 8.6 at.% Ni), as compared to 60 min for a pure Cu(111) foil under identical growth conditions. These are the bulk atomic percentages of Ni, as a superstructure at the surface of these foils with stoichiometry Cu<SUB>6</SUB>Ni<SUB>1</SUB> (for 1.3 to 7.8 bulk at.% Ni in the Cu/Ni(111) foil) was discovered by low energy electron diffraction (LEED). Complete large area monolayer graphene films are either single crystal or close to single crystal, and include folded regions that are essentially parallel and that were likely wrinkles that “fell over” to bind to the surface; these folds are separated by large, wrinkle-free regions. The folds occur due to the buildup of interfacial compressive stress (and its release) during cooling of the foils from 1075 °C to room temperature. The fold heights measured by atomic force microscopy (AFM) and scanning tunneling microscopy (STM) prove them to all be 3 layers thick, and scanning electron microscopy (SEM) imaging shows them to be around 10 to 300 nm wide and separated by roughly 20 μm. These folds are always essentially perpendicular to the steps in this Cu/Ni(111) substrate. Joining of well-aligned graphene islands (in growths that were terminated prior to full film coverage) was investigated with high magnification SEM and aberration-corrected high-resolution transmission electron microscopy (TEM) as well as AFM, STM, and optical microscopy. These methods show that many of the “join regions” have folds, and these arise from interfacial adhesion mechanics (they are due to the buildup of compressive stress during cool-down, but these folds are different than for the continuous graphene films-they occur due to “weak links” in terms of the interface mechanics). Such Cu/Ni(111) alloy foils are promising substrates for the large-scale synthesis of single-crystal graphene film.</P> [FIG OMISSION]</BR>

<i>In Situ</i> Atomic-Scale Observation of Surface-Tension-Induced Structural Transformation of Ag-NiP_<i>x</i> Core-Shell Nanocrystals

Huang, Xing,Liu, Zhongqiang,Millet, Marie-Mathilde,Dong, Jichen,Plodine, Milivoj,Ding, Feng,Schlö,gl, Robert,Willinger, Marc-Georg American Chemical Society 2018 ACS NANO Vol.12 No.7

<P>The properties of nanocrystals are highly dependent on their morphology, composition, and structure. Tailored synthesis over these parameters is successfully applied for the production of nanocrystals with desired properties for specific applications. However, in order to obtain full control over the properties, the behavior of nanocrystals under external stimuli and application conditions needs to be understood. Herein, using Ag-NiP<SUB><I>x</I></SUB> nanocrystals as a model system, we investigate the structural evolution upon thermal treatment by <I>in situ</I> aberration-corrected scanning transmission electron microscopy. A combination of real-time imaging with elemental analysis enables the observation of the transformation from a Ag-NiP<SUB><I>x</I></SUB> core-shell configuration to a Janus structure at the atomic scale. The transformation occurs through dewetting and crystallization of the NiP<SUB><I>x</I></SUB> shell and is accompanied by surface segregation of Ag. Further temperature increase leads to a complete sublimation of Ag and formation of individual Ni<SUB>12</SUB>P<SUB>5</SUB> nanocrystals. The transformation is rationalized by theoretical modeling based on density functional theory calculations. Our model suggests that the transformation is driven by changes of the surface energy of NiP<SUB><I>x</I></SUB> and the interfacial energy between NiP<SUB><I>x</I></SUB> and Ag. The direct observation of atomistic dynamics during thermal-treatment-induced structural modification will help to understand more complex transformations that are induced by aging over time or the interaction with a reactive gas phase in applications such as catalysis.</P> [FIG OMISSION]</BR>

Variants on ESR1 and their Association with Prostate Cancer Risk: A Meta-analysis

Ding, Xiang,Cui, Feng-Mei,Xu, Song-Tao,Pu, Jin-Xian,Huang, Yu-Hua,Zhang, Jiang-Lei,Wei, Xue-Dong,Hou, Jian-Quan,Yan, Chun-Yin Asian Pacific Journal of Cancer Prevention 2012 Asian Pacific journal of cancer prevention Vol.13 No.8

Background: Epidemiological studies evaluating the association of two variants rs9340799 and rs2234693 on estrogen receptor 1 (ESR1) with prostate risk have generated inconsistent results. Methods: A meta-analysis was here conducted to systematically evaluate the relationship of these two variants with prostate cancer susceptibility. Results: For rs9340799, heterozygosity of T/C carriers showed a significant increased prostate cancer risk with a pooled odds ratio (OR) of 1.34 (95% CI = 1.06-1.69) while homozygote C/C carriers showed an increased but not statistically significant association with prostate cancer risk (pooled OR = 1.29, 95% CI = 0.94-1.79). Compared to the homozygous TT carriers, the allele C carriers showed a 31% increased risk for prostate cancer (pooled OR = 1.31, 95% CI = 1.06-1.63). No significant association between the rs2234693 and prostate cancer risk was found with the pooled OR of 1.15 (95% CI = 0.97-1.39, T/C and C/C vs. T/T) under the dominant genetic model. Compared to the homozygote T/T carriers, the heterozygous T/C carriers did not show any significantly different risk of prostate cancer (pooled OR = 1.13, 95% CI = 0.94-1.36) and the homozygous C/C carriers also did not show a significant change for prostate cancer risk compared to the wide-type T/T carriers (pooled OR = 1.26, 95% CI = 0.98-1.62). Conclusion: These data suggested that variant rs9340799, but not rs2234693, on ESR1 confers an elevated risk of prostate cancer.

A Human Case of Lumbosacral Canal Sparganosis in China

Jian-Feng Fan,Sheng Huang,Jing Li,Ren-Jun Peng,He Huang,Xi-Ping Ding,Li-Ping Jiang,Jian Xi 대한기생충학열대의학회 2021 The Korean Journal of Parasitology Vol.59 No.6

Coupled stochastic gradient identification algorithms for multivariate output-error systems using the auxiliary model

Wu Huang,Feng Ding,Tasawar Hayat,Ahmed Alsaedi 제어·로봇·시스템학회 2017 International Journal of Control, Automation, and Vol.15 No.4

This paper considers the gradient based identification problem of a multivariate output-error system. By using the auxiliary model identification idea and the coupling identification concept, an auxiliary model basedstochastic gradient (AM-SG) algorithm and a coupled AM-SG algorithm are presented. The results indicate that theparameter estimation errors converge to zero under the persistent excitation conditions. The simulation examplesconfirm the theoretical results.

c-Cbl-Mediated Neddylation Antagonizes Ubiquitination and Degradation of the TGF-β Type II Receptor

Zuo, W.,Huang, F.,Chiang, Y.,Li, M.,Du, J.,Ding, Y.,Zhang, T.,Lee, H.,Jeong, L.,Chen, Y.,Deng, H.,Feng, X.H.,Luo, S.,Gao, C.,Chen, Y.G. Cell Press 2013 Molecular cell Vol.49 No.3

Transforming growth factor β (TGF-β) is a potent antiproliferative factor in multiple types of cells. Deregulation of TGF-β signaling is associated with the development of many cancers, including leukemia, though the molecular mechanisms are largely unclear. Here, we show that Casitas B-lineage lymphoma (c-Cbl), a known proto-oncogene encoding an ubiquitin E3 ligase, promotes TGF-β signaling by neddylating and stabilizing the type II receptor (TβRII). Knockout of c-Cbl decreases the TβRII protein level and desensitizes hematopoietic stem or progenitor cells to TGF-β stimulation, while c-Cbl overexpression stabilizes TβRII and sensitizes leukemia cells to TGF-β. c-Cbl conjugates neural precursor cell-expressed, developmentally downregulated 8 (NEDD8), a ubiquitin-like protein, to TβRII at Lys556 and Lys567. Neddylation of TβRII promotes its endocytosis to EEA1-positive early endosomes while preventing its endocytosis to caveolin-positive compartments, therefore inhibiting TβRII ubiquitination and degradation. We have also identified a neddylation-activity-defective c-Cbl mutation from leukemia patients, implying a link between aberrant TβRII neddylation and leukemia development.

Response of Saccharomyces cerevisiae to Ethanol Stress Involves Actions of Protein Asrlp

( Jun Mei Ding ),( Xiao Wei Huang ),( Na Zhao ),( Feng Gao ),( Qian Lu ),( Ke Qin Zhang ) 한국미생물 · 생명공학회 2010 Journal of microbiology and biotechnology Vol.20 No.12

During the fermentation process of Saccharomyces cerevisiae, yeast cells must rapidly respond to a wide variety of external stresses in order to survive the constantly changing environment, including ethanol stress. The accumulation of ethanol can severely inhibit cell growth activity and productivity. Thus, the response to changing ethanol concentrations is one of the most important stress reactions in S. cerevisiae and worthy of thorough investigation. Therefore, this study examined the relationship between ethanol tolerance in S. cerevisiae and a unique protein called alcohol sensitive RING/PHD finger 1 protein (Asr1p). A real-time PCR showed that upon exposure to 8% ethanol, the expression of Asr1 was continuously enhanced, reaching a peak 2 h after stimulation. This result was confirmed by monitoring the fluorescence levels using a strain with a green fluorescent protein tagged to the C-terminal of Asr1p. The fluorescent microscopy also revealed a change in the subcellular localization before and after stimulation. Furthermore, the disruption of the Asr1 gene resulted in hypersensitivity on the medium containing ethanol, when compared with the wild-type strain. Thus, when taken together, the present results suggest that Asr1 is involved in the response to ethanol stress in the yeast S. cerevisiae.

Hydrophobic modification of silica/exfoliated graphite nanoplatelets aerogel and its application as supporting material for form-stable phase change materials

Ni Tan,Yang Feng,Ping Hu,QiLin Ding,Chuan-Huang Lin,Yu-Hao Ning,Hao-Nan Zhou,Linping Yu,Zhong Cao,Ju-Lan Zeng 한국공업화학회 2021 Journal of Industrial and Engineering Chemistry Vol.99 No.-

Hydrophobic modified silica/exfoliated graphite nanoplatelets aerogel (M-SiO2/xGnP) were successfullyprepared via surface modification of silica/xGnP alcogel and followed by ambient pressure drying. Afterwards, form-stable PCMs in which capric–palmitic acids eutectic (CA–PA) was confined in theprepared aerogels were obtained by vacuum infiltration. Characterization of the prepared form-stablePCMs revealed that both the hydrophobic modification and the doping of xGnP could effectively improvethe loading of CA–PA in the aerogel. The unmodified silica aerogel could not adsorb CA–PA, while theloading of CA–PA in the surface modified pure silica aerogel supported form-stable PCM and theunmodified silica/xGnP aerogel supported form-stable PCM were 24.2 wt% and 44.4 wt%, respectively. Besides, the hydrophobic modification and the doping of xGnP showed significant synergistic effect. Theloading of CA–PA in the M-SiO2/xGnP supported form-stable PCM (FPCM/xGnP-20-48) could attain78.9 wt% when the M-SiO2/xGnP was obtained by modifying the alcogel with 20 vol% trimethylchlorosilane for 48 h. The FPCM/xGnP-20-48 not only had high latent heat and good thermal reliability,but also exhibited significantly improved thermal conductivity and alleviated supercooling due to theeffective thermal conductive network formed by xGnP and the promoted heterogeneous nucleation ofCA–PA at interfaces with aerogel.

The Feasibility Analysis of Single Curved Screw Drill through the Mouth of the Well Casing

Xia Chengyu,Sun Qiaolei,Feng Ding,Chen Min,Huang Kai,Tu Yiliu 보안공학연구지원센터 2016 International Journal of Multimedia and Ubiquitous Vol.11 No.7

With the development of drilling technology and the needs of the larger Bulit-up, the screw drill with larger structure corner is used more widely in drilling field. Because the existence of single curved screw drill tool with larger structure corner, it have larger friction during the bend PDM in the process of internal casing, so we often need to use the wellhead adjuvant into the well. In order to understand the single bent screw drill into the state in the wellhead diameter of casing, and how the angle of screw structure impact the feasibility, This paper analysis the stress of the single curved screw drilling tools in the well, and the condition it can safely through the mouth of the well conditions, establish the single bend PDM in the calculation wellhead down model. and the finite element model is established combined with the specific parameters of a well which is in the western of SiChuan depression. Using ansys analysis a particular casing inside diameter, under wellhead vertical segment into different structure when the turn of the screw drilling tools down into characteristics and stress distribution characteristics, it is concluded how large of the structure corners and how depth that the bend PDM can rely on gravity well down into the inside diameter of 250.19 mm casing, concluded the relationship between reaction force, friction force, and maximum stress with the well depth and the change of structure corners from 1.5°to 2.75°,provide a basis for drilling site selection of the appropriate combinations of screw drill and how to regulate the radial force of the device while into the well.