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柑桔类病毒分类及其相互关系

浙江柑桔 1990年第3期7卷 52-54页

作者： n.Duran-Vila c.n.Roistacher 萧顺元

历来认为,柑桔裂皮类病毒(cEV)导致枳和兰卜来檬砧木树干裂皮,树体矮化。但是,表现矮化的程度不一样,裂皮形成以及症状表现的时期亦有不同。因此,普遍认为裂皮类病毒内存在不同的毒系。近年来的研究表明,从田间病株上分离到的RnA类病毒... 详细信息

历来认为,柑桔裂皮类病毒(cEV)导致枳和兰卜来檬砧木树干裂皮,树体矮化。但是,表现矮化的程度不一样,裂皮形成以及症状表现的时期亦有不同。因此,普遍认为裂皮类病毒内存在不同的毒系。近年来的研究表明,从田间病株上分离到的RnA类病毒有5种之多。本试验采用先进的类病毒分离、检测、鉴定方法(包括PAGE聚丙烯酰胺凝胶电泳、cF—11纤维素柱层析、分子杂交以及指示植物鉴定),研究了从西班牙以及从美国加州得到的37种柑桔类病毒分离物。

关键词：柑桔裂皮类病毒柑桔类田间病株树体矮化来檬病毒分离病毒分类分子杂交柑桔裂皮病分离物

Quality of spring water used for irrigation in the Almora District of Uttarakhand, India

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chinese Journal Of Geochemistry 2013年第2期32卷 130-136页

作者： bhandari n. S. Hemant K. Joshi Department of chemistry Kumaun University S. S. J. Campus Almora-263601 Uttarakhand India

This paper aims to propose a quality profile of springs of the study area for irrigation. In the present study, fifty-four springs in Almora have been identified from rural as well as urban localities for calculation of irriga- tional water quality parameters during pre-monsoon, monsoon and post-monsoon, 2008. Spring water samples are collected and analyzed for pH, electrical conductivity (Ec), total dissolved solids (TDS), na+ , K+ , ca2+ , Mg2+ , HcO3- , cl- , and SO42- . Different irrigation quality parameters viz. salinity, sodium adsorption ratio (SAR), soluble sodium percentage (SSP), residual sodium carbonate (RSc), magnesium hazards (MH) and permeability index (PI) are calculated for the evaluation of spring water quality for irrigation purposes. All springs are found excellent to good based on irrigation quality parameters. based on Wilcox diagram, about 98% of the water resources are grouped as c1S1 (low-low) and c2S1 (medium-low) classes, so springs are suitable for normal irrigation.

关键词：质量档案灌溉泉水印度钠吸附比水质参数总溶解固体研究区域

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中等专业学校教学用书蒸汽机车学上锅炉

Development of multi-functional nano-paint for energy harvesting applications

1958年

作者： c·И·李索温科 З·b·李索温科

来源：汇雅图书（南通市图书馆... 评论

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Progress in natural Science:Materials International 2018年第1期28卷 1-6页

作者： bir b.bohara Ashok K.batra Department of Physics Chemistry and Mathematics (Materials Science Group) College of Engineering Technology and Physical Sciences Alabama A&M University

The multi-functionality of lead magnesium niobate-lead titanate/paint（PMn-PT/paint） nanocomposite films for energy harvesting via piezoelectric and pyroelectric effects is described. PMn-PT/paint films have been fabricated by a conventional paint-brushing technique to provide a low-cost, low-temperature and low–energy route to create multi-functional films. The properties investigated included dielectric constants, ε' and ε'', as a function of temperature, frequency and composition. From these parameters, it is indicated that the dielectric constants and Ac conductivity(σAc) increase with an increase of filler content and temperature, implying an improvement of the functionality of the films. The results revealed that σAcobeyed the relation σAc=Aωs, and exponents, was found to decrease by increasing the temperature. The correlated barrier hopping was the dominant conduction mechanism in the nanocomposite films. The efforts were made to investigate the performance of nanocomposite films to mechanical vibrations and thermal variations. A cantilever system was designed and examined to assess its performance as energy harvesters. The highest output voltage and power for a PMn-PT/paint based harvester with a broad frequency response operating in the-31-piezoelectric mode were 65 mV and 1 nW, *** and power were shown to be enhanced by application of thermal variations. Thus, films could be utilized for combined energy harvesting via piezoelectric and pyroelectric characteristics.

关键词： Dielectric Pyroelectricity Piezoelectricity nanocomposites PMn-PT Energy harvesting

cooling Augmentation with Microchanneled Structures

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Journal of Thermal Science 1993年第2期2卷 98-110页

作者： X.F.Peng b.X.Wang ThermalEngineeringDepartment TsinghuaUniversityBeijing100084China ThermalEngineeringDepartment Tsin

Experiments were conducted to investigate the heat transfer characteristics and cooling performance of subcooled liquid, water, flowing through rectangular cross-section microchanneled structures machined on a stainless steel plate. Heat transfer or flow mode transition was observed when the heating rate or wall temperature was increased. This transition was found to be suggestively induced by the variation in liquid thermophysical properties due to the significant rise of liquid temperature in the microstructures. The influence of such parameters as liquid velocity, subcooling, property variation, and microchannel geometric configuration on the heat transfer behavior, cooling performance and the heat transfer and liquid flow mode transition were also investigated. The experiments indicated that both slngle-phase forced convection and flow boiling characteristics were quite different from those in normal-sized tubes and the heat transfer was obviously intensified.

关键词： heat transfer convection flow boiling microchanneled structure cooling

Genomic insights into hybridization in a localized region of sympatry between pewee sister species(contopus sordidulus × c. virens) and their chromosomal patterns of differentiation

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chinese birds 2016年第1期7卷 48-55页

作者： Joseph D.Manthey Mark b.Robbins biodiversity Institute University of Kansas Department of Ecology and Evolutionary biology University of Kansas

background: The Great Plains of the United States includes a large number of hybrid and contact zones between bird species. The amount of gene flow between sister species in these zones ranges from very rare hybridization events to widespread and prevalent introgression. Some of these avian systems have been studied extensively, while others have been indeterminate of whether hybridization exists in areas of sympatry. Using genomic-level approaches allows investigation of genomic patterns of hybridization and gene flow between species—or lack ***: We investigated a narrow zone of sympatry in nebraska, USA between pewee species(contopus sordidulus and c. virens), for which no hybridization has been confirmed. We used thousands of single nucleotide polymorphisms to identify potential hybridization and investigate genomic patterns of differentiation between these two ***: We found evidence of multiple hybrid individuals in the contact zone. Little genomic variation was fixed between species, but a large proportion had differentiated allele frequencies between species. There was a positive relationship between genetic differentiation and chromosome ***: We provided the first conclusive evidence of hybridization between c. sordidulus and c. virens, in a region where secondary contact likely occurred due to human disturbance and habitat modification. The genomic patterns of differentiation affirm that these species split in the relatively recent past. Finally, the relationship of chromosome size and genetic differentiation may have resulted from differential rates of chromosomal recombination in songbirds and genetic differentiation between species largely due to genetic drift(possibly in concert with selection).

关键词： contact zone Hybrid zone Hybridization chromosomal patterns next-generation sequencing contopus north America

Electronic and optical properties of TiO_2 and its polymorphs by Z-scan method

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chinese Physics b 2014年第8期23卷 340-344页

作者： S. Divya V P n nampoori P Radhakrishnan A Mujeeb International School of Photonics Cochin University of Science and Technology

TiO2 is a material which has attracted considerable attention from the scientific community for its innumerable prop- erties. TiO2 is known to exist in nature in three different crystalline structures： rutile, anatase, and brookite. Anatase and rutile TiO2 films have been widely characterized for their potential applications in solar cells, self-cleaning coatings, and photocatalysis. In the present report, the third-order nonlinear susceptibilities of TiO2 and its polymorphs, anatase, and rutile, prepared by the sol-gel technique followed by heat treatment are investigated using the Z-scan technique at a wavelength of 532 nm with a duration of 7 ns. Imaginary and real values of Z（3） for amorphous, anatase, and rutile are also calculated and found to be 5 × 10^-19 m2/V2, 27 × 10^-19 m2/V2, 19 × 10^-19 m2/V2, respectively. It is found that the values of the optical constants of amorphous TiO2 after heat treatment vary considerably. It is assumed that this could be due to the variation in the electronic structure of TiO2 synchronous with the formation of its polymorphs, anatase, and rutile. Amorphous TiO2 is marked by the localization of the tail states near the band gap, whereas its crystalline counterparts are characterized by completely delocalized tail states.

关键词： excitons reverse saturable absorption (RSA) excitonic nonlinearity

Dynamic Analysis of the non-Linear behavior of a composite Sandwich beam with a Magnetorheological Elastomer core

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Acta Mechanica Solida Sinica 2016年第3期29卷 271-283页

作者： n. chikh A. nour S. Aguib I. Tawfiq Dynamic of Engines and Vibroacoustic Laboratory M'Hamed Bougara University of Boumerdes Algeria Laboratoire QUARTZ(EA7393) Supmeca 3 rue de Fernand Hainaut 93407 Saint-Ouen Cedex France

This work deals with the active control of the vibrations of mechanical structures incorporating magnetorheological elastomer. The damping coefficient and shear modulus of the elastomer increase when exposed to a magnetic field. compared with the vibration control where the elastomer is permanently exposed to a magnetic field, the control of this process through time reduces vibrations more effectively. The experimental study for the vibrations of a sandwich beam filled with an elastomer is conducted, followed by a numerical study using the Abaqus code. The vibration damping is found to be dependent on the loading rate of micro-size ferromagnetic particles in the elastomer.

关键词： sandwich beam magnetorheological elastomer magnetic field stiffness loss factor

calculation of multicentre nuclear attraction integrals over Slater-type orbitals using unsymmetrical one-range addition theorems

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chinese Physics b 2010年第4期19卷 180-184页

作者： Israfil I.Guseinov n.Seckin Gorgun nimet Zaim Department of Physics Faculty of Arts and SciencesOnsekiz Mart UniversityC anakkaleTurkey Department of Physics Faculty of Arts and SciencesTrakya UniversityEdirneTurkey

Using the unsymmetrical one-range addition theorems introduced by one of the authors with the help of complete orthonormal sets of $／varPsi ^／alpha $-exponential type orbitals （$／alpha = 1,0, - 1, - 2,...）$, this paper presents the sets of series expansion relations for multicentre nuclear attraction integrals over Slater-type orbitals arising in Hartree--Fock--Roothaan equations for molecules. The final results are expressed through multicentre charge density expansion coefficients and basic integrals. The convergence of the series is tested by calculating concrete cases for arbitrary values of parameters of orbitals.

关键词： Slater-type orbitals nuclear attraction integrals Hartree-Fock Roothaan equations unsymmetrical one-range addition theorems