scholarly journals Purification and Characterization of Peach Mosaic Virus

Plant Disease ◽  
1998 ◽  
Vol 82 (8) ◽  
pp. 905-908 ◽  
Author(s):  
Carmen Gispert ◽  
Thomas M. Perring ◽  
Rebecca Creamer

Virus particles were observed by transmission electron microscopy in preparations extracted from symptomatic leaves of Chenopodium amaranticolor that had been mechanically inoculated with peach mosaic virus. The particles were long, flexuous, filamentous rods with an average length of 888 nm. Purified preparations had an A 260/280 nm ratio of 1.25. RNA extracted from purified virus was approximately 8.1 kilobases, and a capsid protein of approximately 27 kDa was found. Polyclonal rabbit antiserum, produced against purified virus, reacted with samples from peach mosaic and cherry mottle leaf-infected plants when used in Western blot analysis.

2008 ◽  
Vol 8 (6) ◽  
pp. 2983-2989 ◽  
Author(s):  
F. Paraguay-Delgado ◽  
R. Huirache-Acuña ◽  
M. Jose-Yacaman ◽  
G. Alonso-Nuñez

In this work, we report the synthesis and characterization of Mo-Ni-W oxides. The precursor was prepared from an aqueous solution of ammonium heptamolibdate, ammonium metatungstate, and nickel nitrate with an atomic ratio of 1:1:1 (Mo:W:Ni). The solution was then transferred to a Teflon-lined stainless steel autoclave and heated to 200 °C and left at this temperature for 48 h. The resulting material was then washed and dried. The morphology and elemental composition were studied by scanning electron microscopy, transmission electron microscopy, energy dispersive X-ray spectroscopy, and X-ray diffraction. The porosity was studied by the Brunauer, Emmett, and Teller method. The materials synthesized at 200 °C remained amorphous and had a specific surface area of 114 m2/g with pore size of 34 Å. The average length was 1 μm and the average diameter was 60 nm. The crystalline phase of synthesized material corresponded to W0.4Mo0.6O3 and WO3. After annealing at 550 °C for two hours, the material was polycrystalline with a segregated structure of MoO3, WO3; NiMoO4 was observed. The sublimation of the molybdenum oxide was evident when annealed at 900 °C for two hours and finally two crystalline phases of material remained; roundish WO3 and elongated particles of NiWO4.


2013 ◽  
Vol 347-350 ◽  
pp. 1196-1198
Author(s):  
Ming Yang ◽  
Juan Juan Xia

Nanorods of CuCl with an average length of 100-200 nm have been prepared by a simple reaction between CuO suspension and NH2OH·HCl in the presence of deionized gelatin at room temperature. Gelatin played a decisive role as an inhibitor of the direct attack of NH2OH·HCl to CuO surfaces and coagulation of the growing CuCl in producing the nanorods. The products were characterized by X-ray powder diffraction and transmission electron microscopy.


2011 ◽  
Vol 415-417 ◽  
pp. 671-676
Author(s):  
Li Gang Liu ◽  
Zhi Qiang Wei ◽  
Xiao Juan Wu ◽  
Ge Zhang

In this paper, Silver nitrate(AgNO3) and polyvinylpyrrolidone (PVP) acted as the silver source and dispersant respectively, the silver nanowires including a small amount of folded structure of silver nanowires, were synthesized by hydrothermal method under the polyol system combined with traces of sodium chloride. The nanowires were characterized by X-ray powder diffraction(XRD), transmission electron microscopy(TEM), selected area electron diffraction(SAED), scanning electron microscopy (SEM), energy dispersive spectrometry (EDAX) and UV-vis absorption spectroscopy to determine the chemical composition, crystal structure, morphology,and the generation mechanism of Ag nanowires was also analysed. The experimental results showed that the crystal structure of the as-prepared Ag nanowires was fcc structure with uniform width, smooth surface, the diameter about 200nm,the average length about 15μm,and the aspect ratio up to 75.The folded structure of silver nanowires synthesized were due to the straight silver nanowires were connected in an end-to-end manner, with obvious spacing between them.


Author(s):  
Ruchama Baum ◽  
J.T. Seto

The ribonucleic acid (RNA) of paramyxoviruses has been characterized by biochemical and physiochemical methods. However, paramyxovirus RNA molecules have not been studied by electron microscopy. The molecular weights of these single-stranded viral RNA molecules are not known as yet. Since electron microscopy has been found to be useful for the characterization of single-stranded RNA, this investigation was initiated to examine the morphology and length measurements of paramyxovirus RNA's.Sendai virus Z strain and Newcastle disease virus (NDV), Milano strain, were used. For these studies it was necessary to develop a method of extracting RNA molecules from purified virus particles. Highly purified Sendai virus was treated with pronase (300 μg/ml) at 37°C for 30 minutes and the RNA extracted by the sodium dodecyl sulfate (SDS)-phenol procedure.


Author(s):  
O. L. Shaffer ◽  
M.S. El-Aasser ◽  
C. L. Zhao ◽  
M. A. Winnik ◽  
R. R. Shivers

Transmission electron microscopy is an important approach to the characterization of the morphology of multiphase latices. Various sample preparation techniques have been applied to multiphase latices such as OsO4, RuO4 and CsOH stains to distinguish the polymer phases or domains. Radiation damage by an electron beam of latices imbedded in ice has also been used as a technique to study particle morphology. Further studies have been developed in the use of freeze-fracture and the effect of differential radiation damage at liquid nitrogen temperatures of the latex particles embedded in ice and not embedded.Two different series of two-stage latices were prepared with (1) a poly(methyl methacrylate) (PMMA) seed and poly(styrene) (PS) second stage; (2) a PS seed and PMMA second stage. Both series have varying amounts of second-stage monomer which was added to the seed latex semicontinuously. A drop of diluted latex was placed on a 200-mesh Formvar-carbon coated copper grid.


Author(s):  
L.E. Murr ◽  
A.B. Draper

The industrial characterization of the machinability of metals and alloys has always been a very arbitrarily defined property, subject to the selection of various reference or test materials; and the adoption of rather naive and misleading interpretations and standards. However, it seems reasonable to assume that with the present state of knowledge of materials properties, and the current theories of solid state physics, more basic guidelines for machinability characterization might be established on the basis of the residual machined microstructures. This approach was originally pursued by Draper; and our presentation here will simply reflect an exposition and extension of this research.The technique consists initially in the production of machined chips of a desired test material on a horizontal milling machine with the workpiece (specimen) mounted on a rotary table vice. A single cut of a specified depth is taken from the workpiece (0.25 in. wide) each at a new tool location.


Author(s):  
K. J. Morrissey

Grain boundaries and interfaces play an important role in determining both physical and mechanical properties of polycrystalline materials. To understand how the structure of interfaces can be controlled to optimize properties, it is necessary to understand and be able to predict their crystal chemistry. Transmission electron microscopy (TEM), analytical electron microscopy (AEM,), and high resolution electron microscopy (HREM) are essential tools for the characterization of the different types of interfaces which exist in ceramic systems. The purpose of this paper is to illustrate some specific areas in which understanding interface structure is important. Interfaces in sintered bodies, materials produced through phase transformation and electronic packaging are discussed.


Author(s):  
George Guthrie ◽  
David Veblen

The nature of a geologic fluid can often be inferred from fluid-filled cavities (generally <100 μm in size) that are trapped during the growth of a mineral. A variety of techniques enables the fluids and daughter crystals (any solid precipitated from the trapped fluid) to be identified from cavities greater than a few micrometers. Many minerals, however, contain fluid inclusions smaller than a micrometer. Though inclusions this small are difficult or impossible to study by conventional techniques, they are ideally suited for study by analytical/ transmission electron microscopy (A/TEM) and electron diffraction. We have used this technique to study fluid inclusions and daughter crystals in diamond and feldspar.Inclusion-rich samples of diamond and feldspar were ion-thinned to electron transparency and examined with a Philips 420T electron microscope (120 keV) equipped with an EDAX beryllium-windowed energy dispersive spectrometer. Thin edges of the sample were perforated in areas that appeared in light microscopy to be populated densely with inclusions. In a few cases, the perforations were bound polygonal sides to which crystals (structurally and compositionally different from the host mineral) were attached (Figure 1).


Author(s):  
G. M. Micha ◽  
L. Zhang

RENi5 (RE: rare earth) based alloys have been extensively evaluated for use as an electrode material for nickel-metal hydride batteries. A variety of alloys have been developed from the prototype intermetallic compound LaNi5. The use of mischmetal as a source of rare earth combined with transition metal and Al substitutions for Ni has caused the evolution of the alloy from a binary compound to one containing eight or more elements. This study evaluated the microstructural features of a complex commercial RENi5 based alloy using scanning and transmission electron microscopy.The alloy was evaluated in the as-cast condition. Its chemistry in at. pct. determined by bulk techniques was 12.1 La, 3.2 Ce, 1.5 Pr, 4.9 Nd, 50.2 Ni, 10.4 Co, 5.3 Mn and 2.0 Al. The as-cast material was of low strength, very brittle and contained a multitude of internal cracks. TEM foils could only be prepared by first embedding pieces of the alloy in epoxy.


Sign in / Sign up

Export Citation Format

Share Document