Research on Coarse-Grained Soil Collapsibility in Gobi Region

2012 ◽  
Vol 446-449 ◽  
pp. 1450-1453 ◽  
Author(s):  
Zhi Hong Nie ◽  
Kun Li ◽  
Jian Xia
Keyword(s):  
Electron Microscopy ◽  
Scanning Electron Microscopy ◽  
Mineral Composition ◽  
Load Test ◽  
Coarse Grained ◽  
Soil Test ◽  
Internal Reasons ◽  
High Degree ◽  
Scanning Electron ◽  
Coarse Grained Soil

This paper has carried out soaking load test, routine soil test, X diffraction, scanning electron microscopy on coarse-grained soil in Gobi region, analyzed the coarse-grained soil collapsibility and explored the mechanism of collapsibility generation. The results showed that: the coarse-grained soil in Gobi region had a high degree of collapsibility; mineral composition, microstructure and salinity constituted the main internal reasons resulting in such phenomenon. In soaking conditions, the cementation strengthen between grains reduces, the structure is damaged under external force and the grain movement leads to greater settlement.

scholarly journals Defects of copper patina / Vady mìdìných patin

2015 ◽  
Vol 59 (3) ◽  
pp. 87-90 ◽  
Author(s):  
J. Stoulil ◽  
P. Šedá ◽  
M. Anisová ◽  
Z. Fencl ◽  
P. Novák ◽  
...  
Keyword(s):  
Electron Microscopy ◽  
Scanning Electron Microscopy ◽  
Image Analysis ◽  
Compact Surface ◽  
Historical Buildings ◽  
X Ray Diffraction ◽  
X Ray ◽  
Destructive Analysis ◽  
High Degree ◽  
Scanning Electron

Abstract The paper is focused on analyses of dark copper patina defects that were formed on one sheet under the same conditions. Roofs of ten historical buildings were studied by image analysis and samples of two roofs were subjected to more detailed destructive analysis. These samples were studied by means of scanning electron microscopy with energy dispersive X-ray spectroscopy, X-ray diffraction and infrared spectroscopy. Both types of patina are composed of brochantite. Green patinas consisted of a pure brochantite and they had a fl at and compact surface. Conversely, black patina contained a high degree of impurities (ammonia cations, nitrates, silicates) and the surface was rough. The proportion of dark patina was higher in south and east facing surfaces, where washing by rainfall is more difficult.

Eucalypt phytoglyphs: The micronanatomical features of the epidermis in relation to taxonomy

1971 ◽  
Vol 19 (2) ◽  
pp. 173 ◽  
Author(s):  
SGM Carr ◽  
L Milkovits ◽  
DJ Carr
Keyword(s):  
Electron Microscopy ◽  
Scanning Electron Microscopy ◽  
Light Microscopy ◽  
Thin Sections ◽  
Hardening Process ◽  
Leaf Surfaces ◽  
The Status ◽  
Species Specific ◽  
High Degree ◽  
Scanning Electron

The eucalypt leaf contains a store of untapped information of potentially great value taxonomic and evututionary studies. Tie cuticie of certain eucalypts is shown to possess a complex and species-specific ornamentation so distinctive that its features can be regarded as diagnostic. The term "phytoglyph" is coined for the constellation of microanatomical features of the surfaces of leaves, including the microanatomy of the cuticle. Phytoglyphic analysis relates to the combination of three methods, light microscopy of stained cuticles, scanning electron microscopy of leaf surfaces, and light microscopy of thin sections of the cuticular and associated structures. Its use is illustrated by the dissection of the "form species" E. dichromophloia into a number of separate and recognizable entities, some of which were previously accorded the status of species. The plant geographical and other implications of this dissection are dealt with. In particular, E. dichromophloia F. Muell. is to be regarded as a species of very restricted distribution. The microanatomical characters of the cuticle are closely controlled products of the epidermal layers. The fact that specimens which (on other grounds) can be grouped together as a species have identical cuticular microanatomy suggests that the phytoglyph is genetically strongly determined and does not consist of inadvertent, trivial surface features with a high degree of plasticity. This in turn raises the problem of the development of the cuticular microanatomy which cannot be explained on current views of the formation of the cuticle by passive diffusion of precursor substances through the epidermal walls, followed by a hardening process.

scholarly journals Porous or non-porous? The challenge of studying unusual placoid sensilla of Megaphragma wasps (Hymenoptera, Trichogrammatidae) with electron microscopy

2021 ◽  
Vol 84 ◽  
pp. 69-73
Author(s):  
Anna V. Diakova ◽  
Alexey A. Polilov
Keyword(s):  
Electron Microscopy ◽  
Scanning Electron Microscopy ◽  
Focused Ion Beam ◽  
Ion Beam ◽  
Accurate Determination ◽  
Apparent Absence ◽  
Olfactory Sensilla ◽  
High Degree ◽  
Scanning Electron

Extreme miniaturization implies a high degree of optimization, rendering the retention of non-functional organs almost impossible. Two unique non-porous placoid sensilla on the antennae of females of Megaphragma were described in the literature. Placoid sensilla in Hymenoptera have an olfactory function and always bear pores; the apparent absence of pores therefore raises the questions whether such sensilla are functional in Megaphragma and whether their surface sculpture had been sufficiently well examined. We examined in detail the external microsculpture and internal ultrastructure of the placoid sensilla using Focused Ion Beam Scanning Electron Microscopy and Scanning Electron Microscopy with various types of sputtering and show that these sensilla actually have a porous cuticle and are innervated by 11 or 12 neurons with branched cilia, which is typical of olfactory sensilla. Comparison of various methods of electron microscopy allows us to conclude that for an accurate determination of the morphofunctional types of sensilla, especially in miniature insects, it is necessary to study both the internal ultrastructure of the sensilla and their external morphology using carefully selected scanning electron microscopy methods.

The Application of Scanning Electron Microscopy with Energy-Dispersive X-Ray Spectroscopy (SEM-EDX) in Ancient Dental Calculus for the Reconstruction of Human Habits

2017 ◽  
Vol 23 (6) ◽  
pp. 1207-1213 ◽  
Author(s):  
Dana Fialová ◽  
Radim Skoupý ◽  
Eva Drozdová ◽  
Aleš Paták ◽  
Jakub Piňos ◽  
...  
Keyword(s):  
Electron Microscopy ◽  
Scanning Electron Microscopy ◽  
Chemical Elements ◽  
Energy Dispersive ◽  
Dental Calculus ◽  
X Ray ◽  
A Charge ◽  
High Degree ◽  
The 19Th Century ◽  
Scanning Electron

AbstractThe great potential of scanning electron microscopy with energy-dispersive X-ray spectroscopy (SEM-EDX) is in detection of unusual chemical elements included in ancient human dental calculus to verify hypotheses about life and burial habits of historic populations and individuals. Elemental spectra were performed from archeological samples of three chosen individuals from different time periods. The unusual presence of magnesium, aluminum, and silicon in the first sample could confirm the hypothesis of high degree of dental abrasion caused by particles from grinding stones in flour. In the second sample, presence of copper could confirm that bronze jewelery could lie near the buried body. The elemental composition of the third sample with the presence of lead and copper confirms the origin of individual to Napoleonic Wars because the damage to his teeth could be explained by the systematic utilization of the teeth for the opening of paper cartridges (a charge with a dose of gunpowder and a bullet), which were used during the 18th and the 19th century AD. All these results contribute to the reconstruction of life (first and third individual) and burial (second individual) habits of historic populations and individuals.

scholarly journals Microstructural characterisation of the Ypresian clays (Kallo-1) at nanometre resolution, using broad-ion beam milling and scanning electron microscopy

2016 ◽  
Vol 95 (3) ◽  
pp. 293-313 ◽  
Author(s):  
S. Hemes ◽  
G. Desbois ◽  
J. Klaver ◽  
J.L. Urai
Keyword(s):  
Electron Microscopy ◽  
Scanning Electron Microscopy ◽  
Power Law ◽  
Ion Beam ◽  
Coarse Grained ◽  
Boom Clay ◽  
Fine Grained ◽  
Pore Size Distributions ◽  
Clay Matrix ◽  
Scanning Electron

AbstractBesides the Oligocene Boom Clay, the Ypresian clays – part of the Eocene Ieper Group (Kortrijk Formation and Kortemark Member) – are currently being investigated as an alternative host rock for the deep geological disposal of radioactive waste in Belgium and the Netherlands. In this study, broad-ion-beam milling and high resolution scanning electron microscopy (BIB-SEM) analyses were carried out to analyse the mineral fabrics and microstructures of representative Ypresian clay samples from different depths of the ON-Kallo-1 borehole (Kallo, Belgium). Qualitative microstructural observations indicate that mineral fabrics and pore morphologies in fine-grained samples are comparable to those found for fine-grained Boom Clay, but most of the Ypresian clay samples analysed also contained a significant silt fraction, which is associated with larger inter-aggregate pores, coated by a thin, very low porous clay layer. Quantitative pore-shape analysis shows lower axial ratios and elongations, as well as higher roundness and circularities for pores in the clay matrix of the more coarse-grained samples, compared to the fine-grained samples. The contribution of large pores (>1 × 107nm² pore area) to the total BIB-SEM observed porosity was found to correlate with the non-clay mineral (NCM) content of a sample. Frequencies of pore sizes within the clay matrix follow a power-law distribution, hinting towards the possibility of up-scaling of the nanometre-scale observations to larger scale (micro-) structural features of the material. Power-law exponents are comparable to values found for power-law pore-size distributions within the clay matrix of the Boom Clay, which indicates similarity of the pore-space morphologies within the clay matrix of the Boom Clay and the Ypresian clays. Wood's metal injection, followed by (cooled BIB)-SEM analysis shows that all visible pores are connected via pore throats of diameter down to ~10 nm.

scholarly journals Roaming of Materials Scientists in Biology: Structural Colours of Butterfly Wings

2019 ◽  
Vol 2 (2) ◽  
pp. 69-72
Author(s):  
László P. Biró ◽  
Krisztián Kertész ◽  
Gábor Piszter ◽  
Zsolt E. Horváth ◽  
Zsolt Bálint
Keyword(s):  
Electron Microscopy ◽  
Scanning Electron Microscopy ◽  
General Plan ◽  
Transmission Electron ◽  
Vis Spectroscopy ◽  
Butterfly Wings ◽  
Species Specific ◽  
High Degree ◽  
Scanning Electron ◽  
Wing Scales

Abstract The photonic nanoarchitectures occurring in the wing scales of Lycaenid butterflies were investigated by scanning electron microscopy (SEM), transmission electron microscopy (TEM) and UV-VIS spectroscopy. We found that the males of all the nine investigated species possess photonic nanoarchitectures built according to the same general “plan”, but each species exhibits species-specific features which results in species-specific colours reproduced generation by generation with a high degree of accuracy.

Pathogenesis of Human Hair Defects

1974 ◽  
Vol 32 ◽  
pp. 12-13
Author(s):  
P.S. Porter ◽  
T. Aoyagi ◽  
R. Matta
Keyword(s):  
Electron Microscopy ◽  
Scanning Electron Microscopy ◽  
Human Hair ◽  
Standard Techniques ◽  
Scanning Electron

Using standard techniques of scanning electron microscopy (SEM), over 1000 human hair defects have been studied. In several of the defects, the pathogenesis of the abnormality has been clarified using these techniques. It is the purpose of this paper to present several distinct morphologic abnormalities of hair and to discuss their pathogenesis as elucidated through techniques of scanning electron microscopy.

Ultrastructural Analysis of the Salivary Glands of Gromphadorhina Portentosa (Schaum)

1977 ◽  
Vol 35 ◽  
pp. 638-639
Author(s):  
P.J. Dailey
Keyword(s):  
Electron Microscopy ◽  
Scanning Electron Microscopy ◽  
Salivary Glands ◽  
Secretory Vesicles ◽  
The Past ◽  
Transmission Electron ◽  
Means Of Transmission ◽  
Gromphadorhina Portentosa ◽  
Scanning Electron ◽  
Topographical Relief

The structure of insect salivary glands has been extensively investigated during the past decade; however, none have attempted scanning electron microscopy (SEM) in ultrastructural examinations of these secretory organs. This study correlates fine structure by means of SEM cryofractography with that of thin-sectioned epoxy embedded material observed by means of transmission electron microscopy (TEM).Salivary glands of Gromphadorhina portentosa were excised and immediately submerged in cold (4°C) paraformaldehyde-glutaraldehyde fixative1 for 2 hr, washed and post-fixed in 1 per cent 0s04 in phosphosphate buffer (4°C for 2 hr). After ethanolic dehydration half of the samples were embedded in Epon 812 for TEM and half cryofractured and subsequently critical point dried for SEM. Dried specimens were mounted on aluminum stubs and coated with approximately 150 Å of gold in a cold sputtering apparatus.Figure 1 shows a cryofractured plane through a salivary acinus revealing topographical relief of secretory vesicles.

Two- or three-way observations of the identical cell elements within the same sections by LM, TEM and/or SEM

1978 ◽  
Vol 36 (2) ◽  
pp. 82-83 ◽  
Author(s):  
Nakazo Watari ◽  
Yasuaki Hotta ◽  
Yoshio Mabuchi
Keyword(s):  
Electron Microscopy ◽  
Scanning Electron Microscopy ◽  
Transmission Electron Microscopy ◽  
Fine Structure ◽  
Light Microscopy ◽  
Thin Sections ◽  
Transmission Electron ◽  
Identical Cell ◽  
Electron Microscopes ◽  
Scanning Electron

It is very useful if we can observe the identical cell elements within the same sections by light microscopy (LM), transmission electron microscopy (TEM) and/or scanning electron microscopy (SEM) sequentially, because, the cell fine structure can not be indicated by LM, while the color is; on the other hand, the cell fine structure can be very easily observed by EM, although its color properties may not. However, there is one problem in that LM requires thick sections of over 1 μm, while EM needs very thin sections of under 100 nm. Recently, we have developed a new method to observe the same cell elements within the same plastic sections using both light and transmission (conventional or high-voltage) electron microscopes.In this paper, we have developed two new observation methods for the identical cell elements within the same sections, both plastic-embedded and paraffin-embedded, using light microscopy, transmission electron microscopy and/or scanning electron microscopy (Fig. 1).

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