A redescription of Metopa species (Amphipoda, Stenothoidae) based on the type material. 1. Zoological Museum, Copenhagen (ZMUC)

Zootaxa ◽  
2009 ◽  
Vol 2093 (1) ◽  
pp. 1-36 ◽  
Author(s):  
ANNE HELENE S. TANDBERG ◽  
WIM VADER

This paper presents redescriptions of amphipods in the genus Metopa (Stenothoidae) in the type-collections of the Zoological Museum of Copenhagen. For Metopa clypeata and M. abyssalis we redescribe the type-specimens, for M. glacialis and M. groenlandica the redescriptions are based on new material and checked against the type-specimens. For all except M. abyssalis a combination of new line drawings and scanning electron microscope (SEM) pictures is provided, for M. abyssalis, line drawings only. A summary of the other species having earlier been designed to Metopa in the Copenhagen collections is given, with a list of their present taxonomic position.

Author(s):  
R. E. Ferrell ◽  
G. G. Paulson

The pore spaces in sandstones are the result of the original depositional fabric and the degree of post-depositional alteration that the rock has experienced. The largest pore volumes are present in coarse-grained, well-sorted materials with high sphericity. The chief mechanisms which alter the shape and size of the pores are precipitation of cementing agents and the dissolution of soluble components. Each process may operate alone or in combination with the other, or there may be several generations of cementation and solution.The scanning electron microscope has ‘been used in this study to reveal the morphology of the pore spaces in a variety of moderate porosity, orthoquartzites.


2015 ◽  
Vol 799-800 ◽  
pp. 125-129
Author(s):  
Mary Donnabelle L. Balela ◽  
April Alexa S. Lagarde ◽  
Stephen Jann A. Tamayo ◽  
Nikko S. Villareal ◽  
Ann Marielle Parreno

Zirconia (ZrO2) nanotubes were synthesized by anodization of zirconium (Zr) foil in NH4Fand (NH4)2SO4 aqueous solution. Different surface preparation methods (electropolishing and etching) were applied on the Zr foil prior to anodizaton. In addition, the anodization time and NH4F concentration were varied. The structure and morphologies of the nanotubes and their crystallinity were confirmed using scanning electron microscope and x-ray diffractometer, respectively. ZrO2 nanotubes with large diameters and thick walls were formed at lower NH4F concentration and longer anodization time. On the other hand, smaller nanotubes with thinner walls were produced when the NH4F concentration was increased. The synthesized nanotubes were predominantly tetragonal ZrO2 with small amounts of monoclinic ZrO2.


Zootaxa ◽  
2007 ◽  
Vol 1544 (1) ◽  
pp. 59-68 ◽  
Author(s):  
NA LI ◽  
BING-ZHONG REN ◽  
MIAO LIU

The types, numbers and distributions of antennal sensilla were studied in both male and female adults of eight Acrididae species in Northeast China using scanning electron microscope (SEM). Totally, there were thirteen types of sensilla found on the antennae. They were identified as trichoid sensilla (I, II), chaetic sensilla (I, II), basiconic sensilla (I, II, III, IV, V), cavity sensilla, coeloconic sensilla, boehm's bristles and paddle-shaped sensilla. The types of antennal sensilla in each Acrididae species ranged from nine to twelve. Each of the species had the same types of antennal sensilla in male and female, and males had more abundant basiconic sensilla, chaetic sensilla, coeloconic sensilla, cavity sensilla than females. Acrida cinerca had the largest total numbers of sensilla, and Euthystria lueifemora had the fewest. Boehm's bristles had a concentration in the base of the pedicel. Paddle-shaped sensilla had a concentration in the base of the scape. There were significant differences in the distribution of the other eleven types of sensilla.


Phytotaxa ◽  
2018 ◽  
Vol 373 (3) ◽  
pp. 169 ◽  
Author(s):  
YUE CAO ◽  
PAN YU ◽  
QINGMIN YOU ◽  
REX L. LOWE ◽  
DAVID M. WILLIAMS ◽  
...  

A new species of Tabularia, Tabularia sinensis, is described from the inland Poyang Lake (Jiangxi Province), the largest lake in China. The description is based on light and scanning electron microscope observations of valve and girdle elements. Given the diversity of forms in the genus, the relationships and status of the genus was investigated in the context of the other known species in the genus and to ascertain if Tabularia, as originally circumscribed, remains monophyletic.


Author(s):  
N. Ollier ◽  
G. Panczer ◽  
B. Champagnon ◽  
P. Jollivet

Abstract Two types of borosilicate leached SON68-type glasses were studied, one doped with uranium and the other with rare-earth element (Nd, Eu). Photoluminescence and cathodoluminescence properties of U doped samples have been correlated to microscopic features of the corroded glass. Nuclear analysis, Electronic Microprobe and Scanning Electron Microscope investigations revealed the heterogeneous composition of the gels with differentiated phases. Enriched U phases (crystallised or not) and phosphorus precipitated phases in rare earth gel have been detected.


1998 ◽  
Vol 4 (S2) ◽  
pp. 896-897
Author(s):  
W. A. Lambe ◽  
P.M. Brady

The variety of instrumentation available to the researcher today can be overwhelming and confusing. Scanning Electron Microscopes (“SEM's) are no exception, and choosing one can often serve as an exercise in dealing with complexity. First time purchasers are most at risk, being subject to a barrage of information that attempts to sway the purchaser in one direction or the other. As a result, one can sometimes be drawn to the details of the latest “high end” performance parameter, while overlooking the basics. At its worst, the selection process can degrade to one of vague guesswork with little hard data to serve as a compass.By applying a methodical approach to define your individual requirements, carefully designed tests of actual instruments, and discussions with your collaborators, potential and experienced users, one can begin to ensure a successful selection process.


Zootaxa ◽  
2019 ◽  
Vol 4674 (4) ◽  
pp. 439-450 ◽  
Author(s):  
ANIL KUMAR DUBEY

A new whitefly species, Asialeyrodes nicobarica Dubey, sp. nov. found infesting Neolamarckia cadamba (Roxb.) (Rubiaceae) on the Nicobar Island, located in the Indian part of the Sundaland hotspot, is described here. Puparia of the new species differ from all of its congeners in shape, and in having the median tubercles on abdominal segments I–VI, a posteriorly notched vasiform orifice and a broad caudal furrow filled with small linear striations. Asialeyrodes menoni Meganathan and David syn. nov and A. tuberculata Pushpa and Sundararaj syn. nov are synonymised with A. indica Sundararaj and David. Icfrealeyrodes splendens (Meganathan & David) comb. nov. is proposed for Asialeyrodes splendens Meganathan and David. Illustrations include habitus, line drawings, holotype images of the new species and A. tuberculata, and scanning electron microscope photomicrographs. Puparial keys differentiating Asialeyrodes Corbett from allied Indian Aleyrodinae genera and to puparia of species currently included in Asialeyrodes in India are provided. Also, the placement of a non-congeneric species, Rhachisphora spherica Sundararaj and Dubey in Asialeyrodes is discussed. 


1971 ◽  
Vol 49 (5) ◽  
pp. 647-649 ◽  
Author(s):  
Bernard R. Baum

This paper describes and evaluates the results of a scanning electron microscopic study of the sculpture of the surfaces of caryopses, glumes, lemmas, awn columns, and awn subules of Avena fatua, normal cultivated oats (A. sativa), fatuoids, and F1 hybrids A. fatua × sativa. Only qualitative differences were sought, and none were detected in the glumes and on the caryopses. The prickles on the lemmas, on the awn columns, and on the awn subules all appear in two character states. In the case of the lemmas one state is found in the normal cultivated oats, fatuoids, and F1 hybrids, and the other in A. fatua. On the other hand in the awn subules one state is found in the normal cultivated oats and the other in fatuoids, F1 hybrids, and A. fatua, while in the awn columns one state occurs in cultivated oats and the other in A. fatua, but in the F1 hybrids and fatuoids both states occur. These findings provide taxonomic evidence additional to that described earlier based on lodicules coupled with traditional characters.


1996 ◽  
Vol 4 (3) ◽  
pp. 18-19
Author(s):  
Janet Tashima ◽  
Jay Lindquist

The cutting-edge tool for IC fab support and defect review brings together the Focused Ion Beam (FIB) technology with the Scanning Electron Microscope (SEM) into a single workstation. The twin beam FIB/SEM workstation, FEI Company's DualBeam™ 820 for example, combines the unique micromachining, microdeposition, and analysis capabilities of a FIB with the high resolution imaging power of a Schottky field emission scanning electron microscope (FE SEM). The full functionality of both instruments is available and neither is compromised by the other.


2021 ◽  
Vol 30 (1) ◽  
Author(s):  
Ehsan Adili ◽  
Moein Riginejad

The present study is an attempt to analyze the effect of micro rubber waste in self- consolidating concrete (SCC) and to compare the concrete containing SCC with conventional additives such as micro SiO2 and nano SiO2. The use of rubber waste can be substantially important from the environmental point of view. Hence, concrete specimens containing 1, 3 and 5% micro rubber waste were made. Moreover, specimens containing 1, 3 and 5% nano SiO2 and 4, 8 and 12% micro SiO2 were prepared to compare their behaviour and microstructure with each other and with the witness specimens. The effect of the other parameters such as the specimen age and the w/c ratio on the microstructure of concrete containing rubber waste was also studied. Thereafter, the specimens were imaged using a scanning electron microscope (SEM) to observe and compare the microcracks in the concrete and secondary electron beam (SE) was used to obtain their images. The results of the microstructural consideration of different specimens showed that 1% of micro rubber waste can improve the behaviour of self-consolidating concrete, but the concrete microstructure strength and quality decline with an increase in its amount.


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