Time Course of the Secondary Deposition of Incrusting Materials on Bordered Pit Membranes in Cryptomeria Japonica

IAWA Journal ◽  
1998 ◽  
Vol 19 (3) ◽  
pp. 285-299 ◽  
Author(s):  
Yuzou Sano ◽  
Ryogo Nakada
Keyword(s):  
Electron Microscopy ◽  
Scanning Electron Microscopy ◽  
Chemical Composition ◽  
Ultraviolet Light ◽  
Cryptomeria Japonica ◽  
Time Course ◽  
Middle Layer ◽  
Bordered Pit ◽  
Innermost Layer ◽  
Scanning Electron

Bordered pit membranes of Cryptomeria japonica were examined successively from the outermost sapwood to the heartwood by scanning electron microscopy and by ultraviolet microspectrophotometry in an attempt to evaluate the time course of the secondary deposition of incrusting materials and to gain clues to their chemical composition. Scanning electron microscopy revealed that the bordered pit membranes were covered by incrusting materials from the middle layer of the sapwood to the heartwood. Both the amount and the appearance of the deposited incrusting materials differed among four regions of the wood, namely, the middle to inner layer of the sapwood, the innermost layer of the sapwood, the intermediate wood and the heartwood. From our results it appears that, in C. japonica, incrusting materials are deposited on bordered pit membranes by stages over several years. Apparent absorption of ultraviolet light by the bordered pit membranes was detected in the analysis of the innermost layer of the sapwood, the intermediate wood and the heartwood. The incrusting materials deposited in these zones were probably phenolic compounds. However, differences in the manner and extent of the absorption of ultraviolet light were found between these three regions of the wood. The results of microspectrophotometric analysis also suggested the phased deposition of incrusting materials at the bordered pit membranes of C. japonica.

The time course of calcium deposition in shells of the barnacle (Balanus amphititre amphititre) during cyprid-juvenile metamorphosis

1994 ◽  
Vol 52 ◽  
pp. 178-179
Author(s):  
Nancy R. Wallace ◽  
Craig C. Freudenrich ◽  
Karl Wilbur ◽  
Peter Ingram ◽  
Ann LeFurgey
Keyword(s):  
Electron Microscopy ◽  
Scanning Electron Microscopy ◽  
Time Course ◽  
Vertical Plane ◽  
Mantle Cavity ◽  
Qualitative Assessment ◽  
Calcium Deposition ◽  
Free Swimming ◽  
Freeze Dried ◽  
Scanning Electron

The morphology of balanomorph barnacles during metamorphosis from the cyprid larval stage to the juvenile has been examined by light microscopy and scanning electron microscopy (SEM). The free-swimming cyprid attaches to a substrate, rotates 90° in the vertical plane, molts, and assumes the adult shape. The resulting metamorph is clad in soft cuticle and has an adult-like appearance with a mantle cavity, thorax with cirri, and incipient shell plates. At some time during the development from cyprid to juvenile, the barnacle begins to mineralize its shell, but it is not known whether calcification occurs before, during, or after ecdysis. To examine this issue, electron probe x-ray microanalysis (EPXMA) was used to detect calcium in cyprids and juveniles at various times during metamorphosis.Laboratory-raised, free-swimming cyprid larvae were allowed to settle on plastic coverslips in culture dishes of seawater. The cyprids were observed with a dissecting microscope, cryopreserved in liquid nitrogen-cooled liquid propane at various times (0-24 h) during metamorphosis, freeze dried, rotary carbon-coated, and examined with scanning electron microscopy (SEM). EPXMA dot maps were obtained in parallel for qualitative assessment of calcium and other elements in the carapace, wall, and opercular plates.

Review — The Orientation of Cellulose Microfibrils in the cell walls of Tracheids in Conifers

IAWA Journal ◽  
2005 ◽  
Vol 26 (2) ◽  
pp. 161-174 ◽  
Author(s):  
Hisashi Abe ◽  
Ryo Funada
Keyword(s):  
Electron Microscopy ◽  
Scanning Electron Microscopy ◽  
Outer Layer ◽  
Cell Walls ◽  
Secondary Wall ◽  
Middle Layer ◽  
Cellulose Microfibrils ◽  
Conifer Species ◽  
Predominant Orientation ◽  
Scanning Electron

We examined the orientation of cellulose microfibrils (Mfs) in the cell walls of tracheids in some conifer species by field emission-scanning electron microscopy (FE-SEM) and developed a model on the basis of our observations. Mfs depositing on the primary walls in differentiating tracheids were not well-ordered. The predominant orientation of the Mfs changed from longitudinal to transverse, as the differentiation of tracheids proceeded. The first Mfs to be deposited in the outer layer of the secondary wall (S1 layer) were arranged as an S-helix. Then the orientation of Mfs changed gradually, with rotation in the clockwise direction as viewed from the lumen side of tracheids, from the outermost to the innermost S1 layer. Mfs in the middle layer of the secondary wall (S2 layer) were oriented in a steep Z-helix with a deviation of less than 15° within the layer. The orientation of Mfs in the inner layer of the secondary wall (S3 layer) changed, with rotation in a counterclockwise direction as viewed from the lumen side, from the outermost to the innermost S3 layer. The angle of orientation of Mfs that were deposited on the innermost S3 layer varied among tracheids from 40° in a Z-helix to 20° in an S-helix.

scholarly journals SEM, EDS and Electrical Capacitance Study on Electrodeposited Ni-Cu Layers

2019 ◽  
Vol 70 (9) ◽  
pp. 3210-3212
Author(s):  
Oana Claudia Ciobotea Barbu ◽  
Ioana Alina Ciobotaru ◽  
Anca Cojocaru ◽  
Florin Mihai Benga ◽  
Danut Ionel Vaireanu
Keyword(s):  
Electron Microscopy ◽  
Scanning Electron Microscopy ◽  
Chemical Composition ◽  
Electrochemical Method ◽  
Steel Substrate ◽  
Distilled Water ◽  
Electrical Capacitance ◽  
Nickel Copper ◽  
Scanning Electron

Nickel-Copper metallic layers were deposited onto a steel substrate by using the electrochemical method. The morphology and the chemical composition of the deposited layers were studied by scanning electron microscopy. The electrical capacitance was measured on a functional supercapacitor made of two Ni-Cu deposited layers and a Nafion 117� membrane hydrated with distilled water, which served as a dielectric separator.

The Fracture Failure Analysis of Precision Centrifuge Spindle

2014 ◽  
Vol 971-973 ◽  
pp. 802-805
Author(s):  
Wei Feng Zhang ◽  
Li Yan ◽  
Fu Xia Zhang
Keyword(s):  
Electron Microscopy ◽  
Scanning Electron Microscopy ◽  
Chemical Composition ◽  
Fracture Mechanics ◽  
Failure Analysis ◽  
Fatigue Failure ◽  
High Speed ◽  
Experimental Results ◽  
Fracture Failure ◽  
Scanning Electron

For the problem of high-speed rotating centrifuge spindle fracture failures, relevant analyses are conducted from the perspective of microstructure, chemical composition and fracture mechanics by using scanning electron microscopy and related instruments. Experimental results and analyses indicate that the spindle fracture is fatigue failure, mainly caused by cold cracks generated on the journal surfacing. Based on the analysis results, improvements and measures are suggested to better solve the spindle weld fracture failure problems.

A comparative study of the morphology, chemical composition and weathering of rhyolitic and andesitic glass

Clay Minerals ◽  
1980 ◽  
Vol 15 (2) ◽  
pp. 165-173 ◽  
Author(s):  
J. H. Kirkman ◽  
W. J. McHardy
Keyword(s):  
Electron Microscopy ◽  
Scanning Electron Microscopy ◽  
New Zealand ◽  
Chemical Composition ◽  
Electron Probe ◽  
Volcanic Glass ◽  
Chemical Activity ◽  
Rapid Rate ◽  
Bonding Characteristics ◽  
Scanning Electron

AbstractThe morphology of volcanic glass particles in rhyolitic and andesitic tephra of central North Island and Taranaki areas of New Zealand has been studied by scanning electron microscopy. Electron probe analyses of the glasses are compared with those of the clays to which they weather. Loss of silica characterizes the weathering of both glasses. The rapid rate of weathering of andesitic glass is attributed to its occurrence as fine, soft microlites and extensive substitution of Al for Si in the structure. Rhyolitic glass weathers more slowly because it occurs as hard and brittle particles containing relatively little alumina. It is suggested that the structure, chemical composition and chemical activity of allophane is governed largely by the chemical composition and bonding characteristics of the parent glass.

The use of plasma etching to reveal the internal structure of Nippostrongylus brasiliensis (Nematoda)

Parasitology ◽  
1983 ◽  
Vol 86 (3) ◽  
pp. 477-480 ◽  
Author(s):  
D. L. Lee ◽  
C. D. Nicholls
Keyword(s):  
Electron Microscopy ◽  
Scanning Electron Microscopy ◽  
Transmission Electron Microscopy ◽  
Internal Structure ◽  
Plasma Etching ◽  
Middle Layer ◽  
Nippostrongylus Brasiliensis ◽  
Cortical Layers ◽  
Transmission Electron ◽  
Scanning Electron

SUMMARYPlasma etching has been used to strip away the cortical layers of the cuticle of adult Nippostrongylus brasiliensis to reveal the struts, with their supporting fibres, which are found in the fluid-filled middle layer of the cuticle, and the basal fibre layers. The etched specimens were studied by means of scanning electron microscopy. The results support earlier work, obtained by transmission electron microscopy, on the cuticle of this nematode. Plasma etching has been shown to have potential in studying the structure of nematodes.

Comparative study of the oxide scale thermally grown on titanium alloys by ion beam analysis techniques and scanning electron microscopy

2008 ◽  
Vol 23 (8) ◽  
pp. 2245-2253 ◽  
Author(s):  
A. Gutiérrez ◽  
F. Pászti ◽  
A. Climent-Font ◽  
J.A. Jiménez ◽  
M.F. López
Keyword(s):  
Electron Microscopy ◽  
Scanning Electron Microscopy ◽  
Chemical Composition ◽  
Titanium Alloys ◽  
Oxide Scale ◽  
Ion Beam ◽  
Elastic Recoil ◽  
Detection Analysis ◽  
Nb Content ◽  
Scanning Electron

In the present work, the oxide layers developed at elevated temperature on three vanadium-free titanium alloys, of interest as implant biomaterials, were studied by Rutherford backscattering spectroscopy, elastic recoil detection analysis, and scanning electron microscopy. The chemical composition of the alloys investigated, in wt%, was Ti–7Nb–6Al, Ti–13Nb–13Zr, and Ti–15Zr–4Nb. Upon oxidation in air at 750 °C, an oxide scale forms, with a chemical composition, morphology, and thickness that depend on the alloy composition and the oxidation time. After equal exposure time, the Ti–7Nb–6Al alloy exhibited the thinnest oxide layer due to the formation of an Al2O3-rich layer. The oxide scale of the two TiNbZr alloys is mainly composed of Ti oxides, with small amounts of Nb and Zr dissolved. For both TiNbZr alloys, the role of the Nb-content on the mechanism of the oxide formation is discussed.

The Microstructure of AlSi7Mg Alloy in as Cast Condition

2015 ◽  
Vol 229 ◽  
pp. 3-10 ◽  
Author(s):  
Bartłomiej Dybowski ◽  
Bogusława Adamczyk-Cieślak ◽  
Kinga Rodak ◽  
Iwona Bednarczyk ◽  
Andrzej Kiełbus ◽  
...  
Keyword(s):  
Electron Microscopy ◽  
Scanning Electron Microscopy ◽  
Transmission Electron Microscopy ◽  
Chemical Composition ◽  
Energy Dispersive Spectrometry ◽  
Intermetallic Phases ◽  
Transmission Electron ◽  
Alloy Microstructure ◽  
Cast Condition ◽  
Scanning Electron

The complex microstructure of as-cast AlSi7Mg alloy has been investigated. Microstructure observations were done using light microscopy, scanning electron microscopy and transmission electron microscopy. Chemical composition of the microstructure constituents was investigated by means of energy dispersive spectrometry, conducted both during SEM and STEM investigations. Selected area diffraction was used to identify the phases in the alloy. Microstructure of the alloy in the as-cast condition consists of Al-Si eutectic and intermetallic phases in the interdendritic regions. These are: Mg2Si, α-AlFeMnS, β-AlFeSi and π-AlFeSiMg phases. What is more, number of fine precipitates were found within the α-Al dendrites. Only the occurrence of U1 (MgAl2Si2) phase has been confirmed.

Synthesis of Cu/Cr and Cu/Cr/W Materials by Powder Metallurgy Techniques

2018 ◽  
Vol 880 ◽  
pp. 241-247
Author(s):  
Claudiu Nicolicescu ◽  
Victor Horia Nicoară ◽  
Costel Silviu Bălulescu
Keyword(s):  
Electron Microscopy ◽  
Mechanical Properties ◽  
Scanning Electron Microscopy ◽  
Powder Metallurgy ◽  
Chemical Composition ◽  
Electrical Properties ◽  
Mechanical Alloying ◽  
Ball Mill ◽  
Weight Percent ◽  
Scanning Electron

Alloys based on Cu/Cr and Cu/Cr/W attract the attention due to their presence in different applications that require higher electrical properties which are combined with good mechanical properties. In order to synthesis the material based on Cu/Cr and Cu/Cr/W, mechanical alloying technique was used. Four mixtures, X1 (99%CuCr), X2 (97%CuCr), X3 (94%Cu1%CrW), X4 (92%Cu3%CrW – weight percent), were prepared using a vario planetary ball mill Pulverisette 4 made by Fritsch. The mixtures obtained after 10 hours were analyzed by scanning electron microscopy (SEM). It was found that the presence of chromium and tungsten influence the morphology and the particles tend to be flat. Sinter ability and microhardness are influenced by the chemical composition of the samples.

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