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Reticulate spore ornamentation in Strobilomyces

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菌物学报 2011年第6期30卷 901-911页

作者： Ronald h.Petersen John Dunlap Karen W.hughes Department of Ecology and Evolutionary Biology University of TennesseeKnoxvilleTN 37996-1100USA Electron Microscope Facility Division of BiologyUniversity of TennesseeKnoxvilleTN 37996-0830USA

Reticulate spore ornamentation in Strobilomyces(Boletaceae,Basidiomycotina) is visible under light microscopy(bright field and phase contrast) up to 1,500×.While some distinctions can be made at this magnification,ontogeny and fine structure of the ornamentation cannot be *** electron microscope images,conversely,reveal significant additional structure from which the ontogenetic process can be *** numerous New and Old World collections,this paper presents evidence distinguishing reticulate ornamentation ontogeny in these disjunct populations.

关键词：网状孢子电子显微镜观察菌物学

The impact of reporting frequency on the information quality of share price： evidence from Chinese state-owned enterprises

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Frontiers of Business Research in China 2018年第2期12卷 83-100页

作者： Yin Toa Lee Wilson h. S. Tong Ernst & Young 22/F CITIC Tower 1 Tim Mei Avenue Central Hong Kong Hong Kong

As a major global exchange, the Stock Exchange of hong Kong （SEhK） only requires semi-annual reporting whereas other major exchanges including the ones in Chinese mainland require quarterly reporting. We argue against the traditional view that higher reporting frequency is necessarily more beneficial. The decision on reporting frequency depends on how the information is being processed by the recipient traders and the results are not obvious. Using a sample of Chinese companies dual- listed in both China A share market and SEhK （Ah shares） as the experimental group and mainland＇s companies listed on SEhK （h shares） only as the control group, we apply the difference-in-difference （DID） method to investigate the impacts of reporting frequency on stock information quality. The results suggest that after China A share market require quarterly financial reporting for all listed companies in 2002, the information asymmetry of the h tranche of Ah stocks increases. Different from prior studies, the results suggest a negative association between stock information quality and financial reporting frequency. We argue that the increased information asymmetry in the h tranche is caused by the noise spilled over from the A tranche. We conduct multivariable GARCh tests and find evidence supporting this conjecture.

关键词： Mainland market hong Kong market Dual-listing Reporting frequency,Information asymmetry Volatility spillover effects

激光诱导聚酰亚胺纳米微结构中分子链取向排列的研究

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高等学校化学学报 1999年第10期20卷 1642-1645页

作者：路庆华 h.hiraoka 王宗光上海交通大学化学化工学院上海200240 香港科技大学化学系

通过Ｎｄ∶ＹＡＧ偏振脉冲激光辐射聚酰亚胺薄膜，在其表面制得大面积纳米级周期性微线条，线条的周期性为２００ｎｍ，线条方向始终平行于偏振激光束电场方向，线条横截面为圆形或椭圆形柱状结构．采用偏振反射红外光谱分别在... 详细信息

通过Ｎｄ∶ＹＡＧ偏振脉冲激光辐射聚酰亚胺薄膜，在其表面制得大面积纳米级周期性微线条，线条的周期性为２００ｎｍ，线条方向始终平行于偏振激光束电场方向，线条横截面为圆形或椭圆形柱状结构．采用偏振反射红外光谱分别在平行与垂直纳米线条的方向上测试聚合物表面分子ＩＲ吸收光谱，结果发现，１７２２和１２３１ｃｍ－１处的吸收有明显的二向色性，表明微线条内聚合物分子链部分呈现取向排列，

关键词：聚酰亚胺分子取向排列纳米微结构激光诱导

Optimization of gas turbines for sustainable turbojet propulsion

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Propulsion and Power Research 2015年第2期4卷 114-121页

作者： Yousef S.h.Najjar Ibrahim A.I.Balawneh Mechanical Engineering Department Jordan University of Science and TechnologyIrbidJordan

Gas-turbines are widely used to power aero planes because they are light,compact with a high power-to-weight *** the turbo jet engine,the main operating variables are:compressor pressure ratio rp and turbine inlet temperature(TIT).These variables affect the specific thrust and specific fuel consumption(SFC),which represent the main performance *** addition to the analytical work,a computer program of the General Algebraic Modeling System(GAMS)was used for analysis and *** analysis shows that the specific thrust strongly depends on turbine inlet temperature(TIT),where a 10%decrease in TIT results in 6.7%decrease in specific thrust and 6.8%decrease in ***,the value of optimum pressure ratio rf for maximum specific thrust increases with TIT.A 10%decrease from design TIT results in 11.43%decrease in *** value of optimum pressure ratio for the turbojet engine operating at Ma=0.8 and altitude Alt=13000 m,and TIT=1700 K was found to be 14.&2015 National Laboratory for Aeronautics and *** and hosting by Elsevier B.V.

关键词： Optimization Green technology Sustainable turbojet engines Performance carpets

Isolation of Microcystins from the Cyanobacterium Planktothrix rubescens Strain No80

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Natural Products and Bioprospecting 2014年第1期4卷 37-45页

作者： Timo h.J.Niedermeyer Peter Schmieder Rainer Kurmayer Cyano Biotech Gmbh Magnusstr.1112489 BerlinGermany Interfaculty Institute for Microbiology and Infection Medicine Tubingen Eberhard Karls University TubingenAuf der Morgenstelle 2872076 TubingenGermany Leibniz Institut fur Molekulare Pharmakologie Robert-Rossle-Str.1013125 BerlinGermany Research Institute for Limnology University of InnsbruckMondseestrasse 95310 MondseeAustria

Three minor microcystins have been isolated from a Planktothrix rubescens *** structures have been elucidated by one-and two-dimensional NMR spectroscopy and high-resolution tandem mass spectrometry as the compounds[Asp^(3),(E)-Dhb^(7)]MC-LY(1),[Asp^(3),(E)-Dhb^(7)]MC-htyW(2),and[Asp^(3),(E)-Dhb^(7)]MC-LW(3).The amino acids found at the variable positions 2 and 4 of the microcystin core structure are in accordance with the predicted amino acid substrate activation selectivities of the non-ribosomal peptide synthetases McyA and McyB described earlier for this *** structural microcystin variants produced by this strain were shown to inhibit protein phosphatase 1 in the nanomolar range.

关键词： Planktothrix Cyanobacteria Microcystins Protein phosphatase inhibition

Effect of initial microstructure on austenite formation kinetics in high-strength experimental microalloyed steels

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International Journal of Minerals,Metallurgy and Materials 2015年第12期22卷 1304-1312页

作者： Edgar López-Martínez Octavio Vázquez-Gómez héctor Javier Vergara-hernández Bernardo Campillo Faculty of Chemistry Metallurgical Engineering Department Autonomous National University of Mexico National Council for Science and Technology Metallurgy Science Postgraduate Programme Morelia Institute of Technology Institute of Physical Sciences Autonomous National University of Mexico

Austenite formation kinetics in two high-strength experimental microalloyed steels with different initial microstructures comprising bainite-martensite and ferrite-martensite/austenite microconstituents was studied during continuous heating by dilatometric analysis. Austenite formation occurred in two steps：（1） carbide dissolution and precipitation and （2） transformation of residual ferrite to austenite. Dilatometric analysis was used to determine the critical temperatures of austenite formation and continuous heating transformation diagrams for heating rates ranging from 0.03°C.s^-1 to 0.67°C.s^-1. The austenite volume fraction was fitted using the Johnson-Mehl-Avrami-Kolmogorov equation to determine the kinetic parameters k and n as functions of the heating rate. Both n and k parameters increased with increasing heat- ing rate, which suggests an increase in the nucleation and growth rates of austenite. The activation energy of austenite formation was determined by the Kissinger method. Two activation energies were associated with each of the two austenite formation steps. In the first step, the austenite growth rate was controlled by carbon diffusion from carbide dissolution and precipitation; in the second step, it was controlled by the dissolution of residual ferrite to austenite.

关键词： non-isothermal kinetics microalloyed steel austenite heating dilatometry

Computational aerodynamic analysis on perimeter reinforced(PR)-compliant wing

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Chinese Journal of Aeronautics 2013年第5期26卷 1093-1105页

作者： N.I.Ismail A.h.Zulkifli M.Z.Abdullah M.hisyam Basri Norazharuddin Shah Abdullah Faculty of Mechanical Engineering Universiti Teknologi MARA40450 Shah AlamSelangorMalaysia School of Mechanical Engineering Universiti Sains MalaysiaEngineering Campus14300 Nibong TebalPenangMalaysia School of Materials and Mineral Resources Engineering Universiti Sains MalaysiaEngineering Campus14300 Nibong TebalPenangMalaysia

Abstract Implementing the morphing technique on a micro air vehicle （MAV） wing is a very chal- lenging task, due to the MAWs wing size limitation and the complex morphing mechanism. As a result, understanding aerodynamic characteristics and flow configurations, subject to wing structure deformation of a morphing wing MAV has remained obstructed. Thus, this paper presents the investigation of structural deformation, aerodynamics performance and flow formation on a pro- posed twist morphing MAV wing design named perimeter reinforced （PR）-compliant wing. The numerical simulation of two-way fluid structure interaction （FSI） investigation consist of a quasi- static aeroelastic structural analysis coupled with 3D incompressible Reynolds-averaged Navier- Stokes and shear-stress-transport （RANS-SST） solver utilized throughout this study. Verification of numerical method on a rigid rectangular wing achieves a good correlation with available exper- imental results. A comparative aeroelastic study between PR-compliant to PR and rigid wing per- formance is organized to elucidate the morphing wing performances. Structural deformation results show that PR-compliant wing is able to alter the wing＇s geometric twist characteristic, which has directly influenced both the overall aerodynamic performance and flow structure behavior. Despite the superior lift performance result, PR-compliant wing also suffers from massive drag penalty, which has consequently affected the wing efficiency in general. Based on vortices investigation, the results reveal the connection between these aerodynamic performances with vortices formation on PR-comoliant wing.

关键词： Aerodynamics Aeroelasticity Fluid structure interaction Micro air vehicle (MAV) Morphing wing

The expansion of Brazilian agriculture:Soil erosion scenarios

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International Soil and Water Conservation Research 2013年第3期1卷 37-48页

作者： Gustavo h.Merten Jean P.G.Minella V isiting Research Professor Dept.of Civil EngineeringL Diversity of MinnesotaMNLSA Department of Soils Federal Lniversity of Santa MariaZip Code 97105900Santa MariaRSBrazil

During the next 10 years Brazil's agricultural area will expand to meet increased domestic and worldwide demand for food,fuel,and *** choices regarding land use will determine to what degree this expansion will have adverse effects that include soil erosion,reservoir siltation,water quality problems,loss of biodiversity and social conflict,especially around indigenous *** paper presents an up-to-date inventory of soil erosion in Brazil caused by crop and livestock activities and provides estimates based on three different hypothetical land-use scenarios to accommodate the expansion of Brazilian agricultural activity by 2020:Scenario 1-expansion of cropping into areas of natural vegetation,without adoption of conservation practices;Scenario 2-expansion of cropping into areas of degraded pasture,without adoption of conservation practices;Scenario 3-expansion of cropping into areas of degraded pasture,together with conservation practices in 100%of the expanded *** worst-case scenario involves expansion of agriculture into areas of native vegetation in the Brazilian Savannah(Cerrado)and Brazilian rainforest(Amazon)biomes,and could increase total soil erosion in Brazil(currently about 800 million metric tons a year)by as much as 20%.In the best-case scenar-io,crop expansion under a conservation agriculture model would utilize currently degraded pasture,especially in the Savannah(circa 40 million hectares),reducing soil erosion in Brazil by around 20%.For this to occur,however,a national soil and water conservation policy needs to be implemented in Brazil to support a sustainable model of agriculture in which the environment can be preserved as much as possible.

关键词： Land use Conservation agriculture Degraded pasture Soil and water conservation policy

Geostatistics for Environmental Applications 2005

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