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A Modified Glass Formation Criterion for Various Glass Forming Liquids with Higher Reliability

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Chinese Physics Letters 2007年第5期24卷 1335-1338页

作者： x. H. Du J. C. Huang Institute of Materials Science and Engineering National Sun Yat-Sen University Kaohsiung 804 Department of Materials Engineering Shenyang Institute of Aeronautical Engineering Shenyang 110034

A modified indicator of the glass forming ability （GFA） from the previous 7 = Tx.（Tl ＋ Tg） for various glass forming liquids is proposed based on a conceptual approach which combines more acceptable physical metallurgy views in terms of the time-temperature-transformation diagrams. It is found that the glass forming ability for glass forming liquids is closely associated mainly with two factors, i.e. （2Tx.- Tg） and Tl （wherein Tx.is the onset crystallization temperature, Tg the glass transition temperature, and Tl the liquidus temperature）, and could be predicated by a unified parameter γm defined as （2Tx.- Tg）/Tl. This approach is confirmed and validated by ex.erimental data in various glass forming systems including ox.de glasses, cryoprotectants and metallic glasses, which all shows a higher reliability when their glass forming ability is predicted by the modified parameter.

关键词： BULK METALLIC GLASSES ABILITY ALLOYS STABILITY SYSTEMS PARAMETERS FRAGILITY

Effects of diurnal adjustment on biases and trends derived from inter-sensor calibrated AMSU-A data

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Frontiers of Earth Science 2018年第1期12卷 1-16页

作者： H. CHEN x. ZOU Z. QIN Department of Atmospheric and Oceanic Sciences University of Colorado Boulder Colorado CO 80309 USA Earth System Science Interdisciplinary Center (ESSIC) University of Maryland College Park Maryland MD 20742 USA Joint Center for Data Assimilation Research and Applications Nanjing University of Information Science and Technology Nanjing 210044 China

Measurements of brightness temperatures from Advanced Microwave Sounding Unit-A （AMSU-A） temperature sounding instruments onboard NOAA Polar- orbiting Operational Environmental Satellites （POES） have been ex.ensively used for studying atmospheric temperature trends over the past several decades. Inter- sensor biases, orbital drifts and diurnal variations of atmospheric and surface temperatures must be considered before using a merged long-term time series of AMSU-A measurements from NOAA- 15, - 18, - 19 and MetOp-A. We study the impacts of the orbital drift and orbital differences of local equator crossing times （LECTs） on temperature trends derivable from AMSU-A using near-nadir observa- tions from NOAA-15, NOAA-18, NOAA-19, and MetOp-A during 1998 - 2014 over the Amazon rainforest. The double difference method is firstly applied to estimation of inter-sensor biases between any two satellites during their overlapping time period. The inter-calibrated observations are then used to generate a monthly mean diurnal cycle of brightness temperature for each AMSU-A channel. A diurnal correction is finally applied each channel to obtain AMSU-A data valid at the same local time. Impacts of the inter-sensor bias correction and diurnal correction on the AMSU-A derived long-term atmospheric temperature trends are separately quantified and compared with those derived from original data. It is shown that the orbital drift and differences of LECT among different POESs induce a large uncertainty in AMSU-A derived long-term warming/cooling trends. After applying an inter-sensor bias correction and a diurnal correction, the warming trends at different local times, which are approx.mately the same, are smaller by half than the trends derived without applying these corrections.

关键词： AMSU-A diurnal adjustment decadal tem-perature trend

A mathematical solution for the parameters of three interfering resonances

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Chinese Physics C 2018年第4期42卷 62-68页

作者： x. Han C.P. Shen School of Physics and Nuclear Energy Engineering Beihang University Beijing 100191 China

The multiple-solution problem in determining the parameters of three interfering resonances from a fit to an ex.erimentally measured distribution is considered from a mathematical viewpoint. It is shown that there are four numerical solutions for a fit with three coherent Breit-Wigner functions. Although ex.licit analytical formulae cannot be derived in this case, we provide some constraint equations between the four solutions. For the cases of nonrelativistic and relativistic Breit-Wigner forms of amplitude functions, a numerical method is provided to derive the other solutions from that already obtained, based on the obtained constraint equations. In real ex.erimental measurements with more complicated amplitude forms similar to Breit-Wigner functions, the same method can be deduced and performed to get numerical solutions. The good agreement between the solutions found using this mathematical method and those directly from the fit verifies the correctness of the constraint equations and mathematical methodology used.

关键词： multiple solutions three interfering resonances high energy physics ex.eriments

Sustainability of China＇s Growth Model A Productivity Perspective

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China & World Economy 2016年第5期24卷 42-70页

作者： Harry x. Wu Institute of Economic Research Hitotsubashi University Japan

In the present paper, the debate on China＇s growth sustainability is first revisited by highlighting the importance of total factor productivity （TFP）. China ＂s TFP performance is then assessed by applying the Jorgensonian aggregate production possibility frontier framework to the latest version of the China lndustry Productivity （CIP） database. We find that of China＇s 8.9-percent annual GDP growth over the period 1980-2012, 7. 0 percentage points （ppts） could be attributed to the growth of labor productivity and 1.9 ppts to the increase in hours worked. Nevertheless, the labor productivity growth is found to be heavily dependent on capital deepening （5.7） rather than TFP growth （0.8）. Notably, the TFP growth turned negative over 2007-2012, which brings into question the sustainability of China＇s growth. Besides, industries that are less prone to state intervention show faster TFP growth than those controlled by the state. Incorporating the Domar aggregation scheme into our model, we further reveal that two-thirds of the TFP growth originates from within industries and the remainder is attributed to a net factor reallocation effect in which labor plays a positive role, whereas capital appears to behave irrationally. Finally, using a revised Maddison-Wu approach to address the potential flaws in official statistics, we arrive at an annual growth rate of 7.2 percent, or 1.7-ppts slower than the 8.9percent obtained based on the CIP data reconstructed using the official national accounts.

关键词： aggregate production possibility frontier Domar weights government intervention resource reallocation total factor productivity

Implementation aspects of a phase-field approach for brittle fracture

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Frontiers of Structural and Civil Engineering 2019年第2期13卷 417-428页

作者： G.D.HUYNH x.,ZHUANG H.NGUYEN-x.AN Institute of Continuum Mechanics Leibniz-Universitat Hannover30167 HannoverGermany Center for Interdisciplinary Research in Technology Ho Chi Minh CityUniversity of Technology (HUTEH)Ho Chi Minh City Vietnam

This paper provides a comprehensive overview of a phase-field model of fracture in solid mechanics setting. We start reviewing the potential energy governing the whole process of fracture including crack initiation, branching or merging. Then, a discretization of system of equation is derived, in which the key aspect is that for the correctness of fracture phenomena, a split into tensile and compressive terms of the strain energy is performed, which allows crack to occur in tension, not in compression. For numerical analysis, standard finite element shape functions are used for both primary fields including displacements and phase field. A staggered scheme which solves the two fields of the problem separately is utilized for solution step and illustrated with a segment of Python code.

关键词： phase-field modeling FEM staggered scheme fracture

SHORT FATIGUE CRACK PARAMETER BASED ON THE TOTAL CRACK AREA

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Acta Metallurgica Sinica(English Letters) 2001年第4期14卷 235-240页

作者： Z.x. Wu and x. C. Wu Engineering College, Yangzhou University, Yangzhou 225009, China Eng. Coll. Yangzhou Univ. Yangzhou 225009 China

The progressive fatigue damage of a material is closely related to the whole population of cracks on its surface. In order to understand which parameter is a more useful indicator of fatigue damage, rotatory bending fatigue tests were carried out using smooth specimens of medium-carbon steel. The behavior of short crack propagation during fatigue was ex.mined and a new parameter total crack area was suggested. The aim of this paper is to ex.end the research on fatigue damage in the already studied steel and to study how these damage parameters are correlated with the process of fatigue damage in order to evaluate the effectiveness of damage detection methods.

关键词： Bending strength Crack initiation Crack propagation Fatigue testing Parameter estimation

Object-Oriented Design for FDTD Visual Scientific Computing

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Journal of Systems Engineering and Electronics 2001年第3期12卷 71-75页

作者： Dong, x. Wang, W. Wang, G. Electromagnetic and Commun. Lab. Sch. of Electronic and Info. Eng. Xi'an Jiaotong University Xi'an 710049 China

A scheme for general purposed FDTD visual scientific computing software is introduced in this paper using object-oriented design (OOD) method. By abstracting the parameters of FDTD grids to an individual class and separating from the iteration procedure, the visual software can be adapted to more comprehensive computing problems. Real-time gray degree graphic and wave curve of the results can be achieved using Directx.technique. The special difference equation and data structure in dispersive medium are considered, and the peculiarity of parameters in perfectly matched layer are also discussed.

关键词： Computational methods Computer aided design Data structures Difference equations Finite difference method Iterative methods Natural sciences computing Object oriented programming Parameter estimation Three dimensional computer graphics Time domain analysis

It takes a team: a gairvof-function story of p53-R249S

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Journal of Molecular Cell Biology 2019年第4期11卷 277-283页

作者： Huai Wang Peng Liao Shelya x. Zeng Hua Lu Department of Biochemistry and Molecular Biology Tulane Cancer Center Tulane University School of Medicine New Orleans LA 70112 USA School of Public Health Nanchang University Nanchang 330006 China Jiangx. Provincial Key Laboratory of Preventive Medicine Nanchang University Nanchang 330006 China

Gain-of-function (GOF), the most malicious oncogenic activity of a cancer-promoting protein, is well illustrated to three hotspot p53 mutations at R248, R175, and R273 with distinct molecular mechanisms. Yet, less is known about another hotspot p53 mutant, R249S (p53-R249S). p53-R249S is the sole hotspot mutation in hepatocellular carcinoma (HCC) that is highly associated with chronic hepatitis B virus (HBV) infection and dietary ex.osure to aflatox.n B1 (AFB1). Its GOF is suggested by the facts that this mutant is associated with earlier onset of HCC and poorer prognosis of cancer patients and that its overex.ression drives HCC proliferation and tumorigenesis. By contrast, simply knocking in this mutant in normal mice did not show apparent GOF activity. Hence, the GOF activity for p53-R249S and its underlying mechanisms have been elusive until recent findings offered some new insights. This review will discuss these findings as well as their clinical significance and implications for the development of a strategy to target multiple molecules as a therapy for p53-R249S-harboring HCC.

关键词： p53-R249S Liver cancer HCC CDK4/cyclin D1 PIN1 c-Myc FBW7a

Optimizing surface-engineered ultra-small gold nanoparticles for highly efficient miRNA delivery to enhance osteogenic differentiation of bone mesenchymal stromal cells

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Nano Research 2017年第1期10卷 49-63页

作者： Meng Yu Bo Lei Chuanbo Gao Jin Yan Peter x. Ma Frontier Institute of Science and Technology Xi'an Jiaotong University Xi'an 710054 China State Key Laboratory for Manufacturing Systems Engineering Xi'an Jiaotong University Xi'an 710054 China State Key Laboratory for Mechanical Behavior of Materials Xi'an Jiootong University Xi'an 710054 China Department of Biomedical Engineering University of Michigan Ann Arbor M148109-2009 USA Macromolecular Science and Engineering Center University of Michigan Ann Arbor M148109-1055 USA Department of Materials Science and Engineering University of Michigan Ann Arbor M148109-1078 USA

Regulation of osteogenic differentiation of bone mesenchymal stromal cells （BMSCs） plays a critical role in bone regeneration. As small non-coding RNAs, microRNAs （miRNAs） play an important role in stem cell differentiation through regulating target-mRNA ex.ression. Unfortunately, highly efficient and safe delivery of miRNAs to BMSCs to regulate their osteogenic differentiation remains challenging. Conventional inorganic nanocrystals have shown increased tox.city owing to their larger size precluding renal clearance. Here, we developed novel, surface-engineered, ultra-small gold nanoparticles （USAuNPs, 〈10 nm） for use as highly efficient miR-5106-delivery systems to enable regulation of BMSC differentiation. We ex.loited the effects of AuNPs coated layer-by-layer with polyethylenimine （PEI） and liposomes （Lipo） to enhance miR-5106-delivery activity and subsequent BMSC differentiation capacity. The PEI- and Lipo-coated AuNPs （Au@PEI@Lipo） showed negligible cytotox.city, good miRNA-5106-binding affinity, highly efficient delivery of miRNAs to BMSCs, and long-term miRNA ex.ression （21 days）. Additionally, compared with commercial Lipofectamine 3000 and 25 kD PEI, the optimized Au@PEI@Lipo-miR-5106 nanocomplex.s significantly enhanced BMSC differentiation into osteoblast-like cells through activation of the Sox. transcription factor. Our findings reveal a promising strategy for the rational design of ultra-small inorganic nanoparticles as highly efficient miRNA-delivery platforms for tissue regeneration and disease therapy.

关键词： ultra-small goldnanoparticles surface engineering microRNA (miRNA)delivery bone mesenchymalstromal cells osteogenic differentiation