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Comparative morphometric and chemical analyses of phenotypes of two invasive ambrosia beetles （Euwallacea spp.） in the United States

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Insect Science 2017年第4期24卷 647-662页

作者： Yigen Chen Paul l. Dallara lori J. Nelson Tom W. Coleman Stacy m. Hishinuma Daniel Carrillo Steven J. Seybold Department of Entomology and Nematology University of California Davis USA USDA Forest Service Pacific Southwest Research Station Davis USDA Forest Service Forest Health Protection San Bemardino California USA Tropical Research and Education Center University of Florida Homestead Florida USA

The polyphagous shot hole borer （PSHB）, Euwallacea sp., was first detected in 2003 in los Angeles County, California, USA. Recently, this invasive species has become a major pest of many hardwood trees in urban and wildland forests throughout southern California. PSHB is nearly identical in morphology and life history to the tea shot hole borer （TSHB）, Euwallaceafornicatus, an invasive pest of hardwoods in Florida, USA and many other parts of the world. However, molecular studies have suggested that the taxa are different species. We conducted morphometric and chemical analyses of the pheno- types of Euwallacea sp. collected in southern California （los Angeles County） and E. fornicatus collected in Florida （miami-Dade County）. Our analyses indicated that PSHB has 3 larval instars. The third larval instar was separated from the first 2 instars by head capsule width with 0 probability of misclassification. The body length, head width, and pronotal width of PSHB adult males were significantly less than those of females. Head width and pronotal width of female PSHB were significantly less than those of female TSHB. In contrast, body length, and ratio of body length to pronotal width of female PSHB were significantly greater than those of female TSHB. However, females of these 2 species could not be separated completely by these 4 measurements because of the overlapping ranges. Cuticular hydrocarbons detected in both species were exclusively alkanes （i.e., n-alkanes, monomethylalkanes, dimethylalkanes, and trimethylalkanes）. Cuticular hydro- carbon profiles of PSHB males and females were similar, but they both differed from that of TSHB females. Cuticular hydrocarbons of PSHB were predominantly internally branched dimethylalkanes with backbones of 31 and 33 carbons, whereas cuticular hydro- carbons of TSHB females were dominated by internally branched monomethylalkanes and dimethylalkanes with backbones of 28 and 29 carbons. multiple compounds within these classes appear

关键词： cuticular hydrocarbons Euwallaceafornicatus larval instars polyphagousshot hole borer Scolytidae tea shot hole borer

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Noninvasive study of structural and functional features of neonatal skin

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Journal of Innovative Optical Health Sciences 2014年第3期7卷 40-49页

作者： I.l.Shlivko V.A.Kamensky m.Y.Kirillin P.D.Agrba O.E.Garanina m.S.Neznakhina D.O.Ellinsky A.S.maksimova E.V.Donchenko Nizhny Novgorod State medical Academy 603005 minin and Pozharsky Square 10/1 Nizhny Nougoro dRussia Institute of Applied Physics R.AS603950 Ulyanou str.46 Nizhny NovugorodRussia Nizhngy Novgorod Research Institute of Traumatology.and Orthopedics 603155 Verkhnevolzhskaya Embankment 18 Nizhny NougorodRussia

In the present paper,we describe the first complex multifocal noninvasive morphological andfunctional study that enabled us to define specific qualitative and quantitative features of neo-natal skin.A complex morphofunctional examination of 10 infants aging from 1 to 28 days wasperformed by optical coherence tomography(OCT)device with a flexible probe at the wavelength of 920 nm with longitudinal resolution of 20μm and transverse resolution of 25μm with simultaneous measurement of skin functional *** OCT images of neonatal thin skinhave organized layered structure with four horizontally oriented *** skin of newbornshas no structure typical for adult skin and no clear transition from the papillary to the ***,we show for the first time to our knowledge that neonatal thick skin differs structurally and functionally from adult ***,it differs by a loose arrangement of stratum corneum squamae and thinner epidermis and papilary layer of *** functionaldifferences are lower transepidermal water loss,localization-dependent humidity,higher ery,thema level,and lower *** principal structural diferences between neonatal andadult skin show that skin structure formation is not completed by the moment of birth.

关键词： Optical coherence tomography skin skin barrier neonate.

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基于粗颗粒动态演化过程的高铁填料振动压实机理研究

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岩土工程学报 2024年第4期46卷 803-813页

作者：谢康陈晓斌尧俊凯李泰灃王业顺邓志兴吕鑫龙中南大学土木工程学院湖南长沙410075 中国铁道科学研究院集团有限公司铁道建筑研究所北京100081

为了揭示高铁粗粒土填料振动压实机理,以典型的高铁基床表层级配碎石填料为研究对象,首先基于自行研制的大型振动压实仪,建立连续干密度ρ_(rd)、动刚度Krb以及修正地基系数K20的压实质量评估体系;然后利用X-CT对压实过程中的级配碎石... 详细信息

为了揭示高铁粗粒土填料振动压实机理,以典型的高铁基床表层级配碎石填料为研究对象,首先基于自行研制的大型振动压实仪,建立连续干密度ρ_(rd)、动刚度Krb以及修正地基系数K20的压实质量评估体系;然后利用X-CT对压实过程中的级配碎石进行扫描,从粗颗粒动态演化角度揭示级配碎石的压实机制。研究结果表明:整个压实过程中,不同土体类型的级配碎石ρ_(rd)均呈现出急速上升-缓慢上升的趋势,而Krb和K20却呈现出急速上升-缓慢下降的趋势。进一步,提出压实嵌锁点Tlp以量化出级配碎石的压实性能拐点特征。振动压实过程中当60%的粗颗粒长轴趋于水平排布时(处于Tlp状态),即呈现出振动压实稳定态;而后进一步压实,易导致粗颗粒发生以表面研磨为主的破碎现象,破坏骨架稳定性,降低压实性能。最终通过离散元模拟验证该机制的正确性。研究成果可从细观层面揭示振动压实机理,为高铁智能碾压质量评估提供新的方法。

关键词：高铁路基级配碎石压实机理 X-CT 动态演化量化表征

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Kinetics of carbonated decomposition of hydrogarnet with different silica saturation coefficients

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International Journal of minerals,metallurgy and materials 2020年第4期27卷 472-482页

作者： Xiao-feng Zhu Ting-an Zhang Guo-zhi lü State Key laboratory of Advanced Processing and Recycling of Nonferrous metals Lanzhou University of TechnologyLanzhou 730050China School of material Science and Engineering Lanzhou University of TechnologyLanzhou 730050China Key laboratory for Ecological metallurgy of multimetallic mineral(ministry of Education Northeastern UniversityShenyang 110819China Special metallurgy and Process Engineering Institute School of MetallurgyNortheastern UniversityShenyang 110819China

Carbonated decomposition of hydrogarnet is one of the vital reactions of the calcification–carbonation method,which is designed to dispose of low-grade bauxite and Bayer red mud and is a novel eco-friendly *** this study,the effect of the silica saturation coefficient(x)on the carbonation of hydrogarnet was investigated from the kinetic *** results indicated that the carbonation of hydrogarnets with different x values(x=0.27,0.36,0.70,and 0.73)underwent two stages with significantly different rates,and the kinetic mechanisms of the two stages can be described by the kinetic functions R3 and *** apparent activation energies at Stages 1 and 2 were 41.96–81.64 and 14.80–34.84 kJ/mol,***,the corresponding limiting steps of the two stages were interfacial chemical reaction and diffusion.

关键词： Bayer red mud hydrogarnet calcification carbonation kinetics silica saturation coefficient

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Co^(2+) substituted mg–Cu–Zn ferrite: Evaluation of structural,magnetic,and electromagnetic properties

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Journal of Advanced Ceramics 2018年第3期7卷 207-217页

作者： l.m.THORAT J.Y.PATIl D.Y.NADARGI U.R.GHODAKE R.C.KAmBAlE S.S.SURYAVANSHI Department of Electronics S.M.Dnyandeo Mohekar Mahavidyalaya School of Physical Sciences Solapur University Department of Electronics Shri Shivaji Mahavidyalaya Department of Physics Savitribai Phule Pune University

We report the synthesis of Co^(2+)substituted mg–Cu–Zn ferrite via citrate gel combustion process and thereby its structural,transport,and magnetic properties for the use in electromagnetic energy absorption *** polycrystalline ferrite system is investigated by interplay of stoichiometric composition with mg_(0.25–x)Co_x Cu_(0.25)Zn_(0.5)Fe_2O_4(0≤x≤0.25).Structural investigations using X-ray diffraction(XRD)and selected area electron diffraction(SAED)reveal the formation of spinel structure with linear growth of lattice constant due to Co^(2+)*** microstructural analysis(TEm and SEm)depicts the dense microstructure with the average grain size of 0.42–1.25μ*** elemental analysis(EDS)confirms the elemental composition of the as-prepared ferrite with respect to the initial concentrations of the synthetic composition *** observed variations in initial permeability(μ_i)and magnetic moment(_Bn)are explained based on deviation in saturation magnetization(m_s),anisotropy constant(_1K),density values,and exchange *** temperature dependence of DC resistivity confirms the semiconducting behavior of the as-prepared ferrite material,with an increase in the DC resistivity by an incorporation of ***,the effects of adding Co^(2+)on the Curie temperature,frequency dependent dielectric properties of the ferrite material are also discussed.

关键词： Co-mg-Cu-Zn ferrite spinel phase electrical resistivity saturation magnetization anisotropy constant Curie temperature

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Comparison study on water use efficiency of wheat flag leaf

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Chinese Science Bulletin 1998年第14期43卷 1205-1211页

作者： Zhang, ZB Shan, l Chinese Acad Sci Inst Soil & Water Conservat State Key Lab Soil Eros & Dryland Farming Loess P Yangling 712100 Peoples R China

wild species and cultivars were planted under irrigated and dryland field condition. lCA\|3 model photosynthesis apparatus was employed to measure flag leaf WUE. The results show that WUE of diploid and tetraploid increases as the wild species became cultivated species. WUE of flag leaf increases as the chromosome ploid increases (2\%n\%→4\%n\%→6\%n\%) in the wheat evolution. Among modern cultivars, WUE of most irrigated varieties is higher than that of dryland varieties.

关键词： wheat flag leaf water use efficiency.

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外圆鱼鳞结构化表面的研磨研究

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现代制造工程 2024年第5期 10-14页

作者：陈超吕玉山李兴山智佳琦沈阳理工大学机械工程学院沈阳110159

为了在外圆工件表面上研磨出具有随行波结构特征的鱼鳞表面结构,首先基于对自然界中鱼鳞表面形貌的特征分析,建立起外圆工件沿轴向排布的鱼鳞结构化表面数学模型;其次依据外圆研磨原理以及拓扑学理论,设计出用于研磨外圆鱼鳞表面的结构... 详细信息

为了在外圆工件表面上研磨出具有随行波结构特征的鱼鳞表面结构,首先基于对自然界中鱼鳞表面形貌的特征分析,建立起外圆工件沿轴向排布的鱼鳞结构化表面数学模型;其次依据外圆研磨原理以及拓扑学理论,设计出用于研磨外圆鱼鳞表面的结构化拓扑油石;然后依据外圆研磨的磨粒运动轨迹,讨论实现外圆鱼鳞结构化表面研磨的边界条件;并对外圆研磨过程进行仿真模拟,获得了具有随行波结构的鱼鳞结构化表面。研究结果表明,利用所设计的结构化拓扑油石可以实现外圆鱼鳞结构化表面的研磨;改变研磨的振幅和频率,鱼鳞结构化表面的形状参数也会变化,但其表面拓扑属性不变。

关键词：外圆研磨鱼鳞表面结构化油石拓扑映射随行波

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用工业炉生产不锈钢的熔融还原试验结果：用熔融还原法生产不锈钢试验之二

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重钢技术 1989年第3期 75-76页

作者： rai,T. 刘祖尧

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An Application of the level Set method to Underwater Acoustic Propagation

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Communications in Computational Physics 2012年第10期12卷 1359-1391页

作者： Sheri l.martinelli Torpedo Systems Department Naval Undersea Warfare Center1176 Howell StreetNewportRhode Island 02841USA Division of Applied mathematics Brown UniversityProvidenceRhode Island 02912USA

An algorithm for computing wavefronts,based on the high frequency approximation to the wave equation,is *** technique applies the level set method to underwater acoustic wavefront propagation in the time *** level set method allows for computation of the acoustic phase function using established numerical techniques to solve a first order transport equation to a desired order of *** methods for solving the eikonal equation directly on a fixed grid limit one to only the first arrivals,so these approaches are not useful when multi-path propagation is *** the level set model to the problem allows for the time domain computation of the phase function on a fixed grid,without having to restrict to first arrival *** implementation presented has no restrictions on range dependence or direction of travel,and offers improved efficiency over solving the full wave equation which under the high frequency assumption requires a large number of grid points to resolve the highly oscillatory *** conditions are discussed,and an approach is suggested for producing good results in the presence of boundary *** efficientmethod to compute the amplitude from the level set method solutions is also *** to analytical solutions are presented where available,and numerical results are validated by comparing results with exact solutions where available,a full wave equation solver,and with wavefronts extracted from ray tracing software.

关键词： Geometric acoustics level set method high-frequency acoustic propagation WENO method

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lIGHT PORTABlE ElECTROPNEUmATIC lOUDSPEAKER

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Chinese Journal of Acoustics 1989年第4期8卷 359-365页

作者： mACDONAlD D.l. Racal Acoustics ltd.U.K

This paper analyses the influence of certain parameters and factors on the characteristics of the electropneumatic loudspeaker and describes the experimental work carried out. The developed portable electropneumatic loudspeaker possesses good properties with a flat frequency response from 400 Hz to 2 kHz and a maximum sound pressrue output of 120dB at a distance 2 metre on axis from the horn mouth .The magnetic flux density at the magnetic gap is 19 ,000 gauss .The electropneumatic loudspeaker is small in size and lightweight.

关键词： lIGHT PORTABlE ElECTROPNEUmATIC lOUDSPEAKER

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