Discovery and origin of a Palaeogene smectite-bearing clay deposit in the SE Gobi (Mongolia)

Clay Minerals ◽  
2005 ◽  
Vol 40 (3) ◽  
pp. 351-367 ◽  
Author(s):  
H. G. Dill ◽  
S. Kaufhold ◽  
S. Khishigsuren ◽  
J. Bulgamaa
Keyword(s):  
Drainage System ◽  
Exchange Capacity ◽  
Infrared Spectrometry ◽  
X Ray Diffraction ◽  
Thin Sections ◽  
Ir Spectrometry ◽  
X Ray ◽  
Reference Sections ◽  
Basin Edge

AbstractThe smectite-bearing red bed series of the Palaeogene Ergeliin zoo Formation in Mongolia is part of an alluvial-fluvial fan prograding over prodelta/mudflat deposits. The series was investigated in the field (mapping and portable infrared (IR) spectrometry in the short wavelength (SW) range) and samples were analysed in the laboratory using thin sections, X-ray diffraction, X-ray fluorescence, cation exchange capacity and Fourier transform infrared spectrometry in the mid-IR range. Two reference sections are treated in more detail as to the environment of deposition and concentration of smectite. The deposits at Ulaan uul are representative of a distal fan section with prevalent mudflats, whereas Ulaan buur offers insight into a braided river drainage system. Metabasic rocks in the hinterland delivered mica and chlorite from which smectite originated during diagenesis under semi-arid climatic and surface-near conditions. Towards the basin edge, smectite is replaced by kaolinite. The prime area in which we were interested in the smectite is the most distal part of the alluvial-fluvial fan, which was the subject of a field-based IR survey. This exploration method is a valuable tool to obtain a quick overview of the mineral composition and reduce the number of samples in the field for follow-up analyses. Its weak and strong points are discussed.

Electron Microscopy of Human Gallstones

1971 ◽  
Vol 29 ◽  
pp. 296-297
Author(s):  
C. Wolpers ◽  
R. Blaschke
Keyword(s):  
Electron Microscopy ◽  
Room Temperature ◽  
Bile Pigment ◽  
X Ray Diffraction ◽  
Triclinic Crystal System ◽  
X Ray ◽  
Follow Up Study ◽  
Infra Red ◽  
Main Components

Scanning microscopy was used to study the surface of human gallstones and the surface of fractures. The specimens were obtained by operation, washed with water, dried at room temperature and shadowcasted with carbon and aluminum. Most of the specimens belong to patients from a series of X-ray follow-up study, examined during the last twenty years. So it was possible to evaluate approximately the age of these gallstones and to get information on the intensity of growing and solving.Cholesterol, a group of bile pigment substances and different salts of calcium, are the main components of human gallstones. By X-ray diffraction technique, infra-red spectroscopy and by chemical analysis it was demonstrated that all three components can be found in any gallstone. In the presence of water cholesterol crystallizes in pane-like plates of the triclinic crystal system.

Chemical modification of the bacterial wall to determine sites of metal deposition

1978 ◽  
Vol 36 (2) ◽  
pp. 350-351
Author(s):  
T. J. Beveridge
Keyword(s):  
Electron Scattering ◽  
Metal Salt ◽  
Metal Deposition ◽  
Suitable Model ◽  
X Ray Diffraction ◽  
Subtilis Cell ◽  
Thin Sections ◽  
X Ray ◽  
Section Data ◽  
Metal Impregnation

The Bacillus subtilis cell wall provides a protective sacculus about the vital constituents of the bacterium and consists of a collection of anionic hetero- and homopolymers which are mainly polysaccharidic. We recently demonstrated that unfixed walls were able to trap and retain substantial amounts of metal when suspended in aqueous metal salt solutions. These walls were briefly mixed with low concentration metal solutions (5mM for 10 min at 22°C), were well washed with deionized distilled water, and the quantity of metal uptake (atomic absorption and X-ray fluorescence), the type of staining response (electron scattering profile of thin-sections), and the crystallinity of the deposition product (X-ray diffraction of embedded specimens) determined.Since most biological material possesses little electron scattering ability electron microscopists have been forced to depend on heavy metal impregnation of the specimen before obtaining thin-section data. Our experience with these walls suggested that they may provide a suitable model system with which to study the sites of reaction for this metal deposition.

scholarly journals Modified Lime Binders for Restoration Work

Buildings ◽  
2021 ◽  
Vol 11 (3) ◽  
pp. 98
Author(s):  
Valentina Loganina ◽  
Kristina Sergeeva ◽  
Roman Fediuk ◽  
Sergey Klyuev ◽  
Nikolai Vatin ◽  
...  
Keyword(s):  
Storage Time ◽  
Infrared Spectrometry ◽  
X Ray Diffraction ◽  
X Ray ◽  
Gain Rate ◽  
Calcium Silicate Hydrates ◽  
Restoration Work ◽  
Weather Resistance ◽  
Kinetics Of ◽  
Mixing Water

Lime mixes are the primary material for restoration work in historic buildings. The research object of this study is modifying lime binders with specially synthesized calcium silicate hydrates (CSHs). This study aimed to improve lime render mixes’ weather resistance. The following factors were considered: the density of the liquid glass, the amount of the precipitating additive, the rate of introduction of the precipitating additive, the drying mode of the precipitate, and the storage time of the precipitate. The research methods were X-ray diffraction analysis, differential thermal analysis, Fourier transform infrared spectrometry, and optical and electron microscopy. It was revealed that lime compositions with CSH have a higher strength gain rate than the control compositions. A mathematical model of the kinetics of hardening a lime composite based on a binder filled with CSH was obtained. The regularities of the change in the lime composite’s strength depending on the filler grinding’s fineness, its content, and the amount of mixing water have been established. It was revealed that the introduction of CSH into the lime composition increases the weather resistance of facade lime mixtures by reducing the porosity and increasing the volume of closed pores of the composite.

Extracellular Matrix Molecules Involved in Barnacle Shell Mineralization

2002 ◽  
Vol 724 ◽  
Author(s):  
María S. Fernández ◽  
Italo Vergara ◽  
Alejandro Oyarzún ◽  
José I. Arias ◽  
Renato Rodríguez ◽  
...  
Keyword(s):  
Infrared Spectrometry ◽  
X Ray Diffraction ◽  
X Ray ◽  
Organic Composition ◽  
Shell Matrix ◽  
Extracellular Matrix Molecules ◽  
Immuno Histochemistry ◽  
Hard Shell ◽  
Basal Disk ◽  
Crystalline Microstructure

AbstractAustromegabalanus psittacusis a large (normally up to 30 cm high) sessile balanomorph barnacle from the coast of Chile and South Peru. Its hard shell is composed of twelve calcareous side plates, six parietes and six radii, joined in the form of a truncated cone opened at the top. Plates rest on a basal disk firmly cemented to the substratum. Although the crystalline microstructure of barnacle's shell has been studied to some extent, its organic composition and the mechanisms governing the biomineralization of such highly ordered nanocomposite have remained obscure. By using X-ray diffraction, infrared spectrometry, SEM and TEM electron microscopy, histochemistry, immuno-histochemistry and -ultrastructure, biochemistry and a crystallization assay, we have studied the cell-shell interactions, the crystalline microstructure of the inorganic moiety and the localization of particular macromolecules, and tested their influence on crystallization.The mineral of the plates and basal disk was calcite showing a (104) preferential orientation. Plates were not solid but porous. While parietes have longitudinal canals (from the base to the apex), radii have transversal canals arranged parallel to the base. These canals are not in the center of the plates but displaced to the outside of the shell delimiting a thinner solid outer lamina and a thicker inner one. The inner lamina consisted of parallel calcified layers separated by organic sheets. These sheets showed autofluorescence and consisted of chitin surrounded by proteoglycans and other minor proteins, which seems to be responsible for the fluorescent behaviour. These organic sheets were also organized as several concentric rings around the canals. The shell matrix obtained after decalcification, which surrounded the crystals, also contained a loose net of such proteoglycans. Mantle epithelial cells covered the entire surface of the inner side of the inner lamina and extend to the plate canals. While isolated chitin did not promote or alter calcite crystallization, the proteoglycan-rich fraction dramatically modified crystal morphology and size. As we have demonstrated in another model of biomineralization, such as the eggshell, hereby we suggest that these structured polyanionic proteoglycan moieties could also be part of the regulatory mechanisms of the barnacle shell mineralization.

The petrology of the Mount Padbury mesosiderite and its achondrite enclaves

1966 ◽  
Vol 36 (276) ◽  
pp. 1029-1060 ◽  
Author(s):  
G. J. H. McCall
Keyword(s):  
Microscopic Analysis ◽  
Host Material ◽  
Refractive Indices ◽  
X Ray Diffraction ◽  
Thin Sections ◽  
X Ray ◽  
Wide Range ◽  
Varied Range ◽  
Optical Determination

SummaryThe petrography of the Mount Padbury meteorite, previously briefly recorded, is described in some detail. Both the metalliferous host material of the mesosiderite and the varied range of silicate-rich, virtually metal-free enclaves (including both familiar achondrite material and unfamiliar achondrite material) are described. Eucrite, brecciated eucrite, and a peculiar ‘shocked’ form of eucrite (resembling some terrestrial flaser-gabbros) are the calcium-rich achondrite types represented; hypersthene achondrite (including typical diogenite material and unfamiliar material) and olivine achondrite (granular aggregates of olivine not entirely similar to the unique chassignite and single crystals up to 4 in. in length) are the calcium-poor achondrite types represented. The eucrite displays more or less uniform mineralogy, but the mineral constituents are present in varying proportions, and there is a wide range of textural variations recognized. The silicate grain fragments enclosed in the metallic reticulation to form the mesosiderite host material are, significantly, entirely of minerals seen within the achondrite enclaves—plagioclase, hypersthene, pigeonite, olivine, and tridymite.These results include microscopic analysis of thin sections and polished sections, X-ray diffraction studies, optical determination of refractive indices using mineral grain mounts, and chemical analyses.The wider implications of this new and unique meteorite find are briefly considered.

scholarly journals Purification, Characterization, and Time-Dependent Adsorption Studies of Ghanaian Muscovite Clay

2018 ◽  
Vol 2018 ◽  
pp. 1-8 ◽  
Author(s):  
Samuel Tetteh ◽  
Andrews Quashie ◽  
Michael Akrofi Anang
Keyword(s):  
Exchange Capacity ◽  
Time Dependent ◽  
Point Of Zero Charge ◽  
X Ray Diffraction ◽  
X Ray ◽  
Adsorption Studies ◽  
Morphological Studies ◽  
Ft Ir ◽  
Crystalline Nature ◽  
Different Parts

Three clay samples (E1, E2, and C1) extracted from different parts of Ghana have been purified by sedimentation. The samples were further characterized by powder X-ray diffraction (PXRD), Fourier transform infrared spectroscopy (FT-IR), scanning electron microscopy (SEM), cation exchange capacity (CEC), and point of zero charge (pHpzc). PXRD and FT-IR data revealed the samples to be predominantly muscovite clay with percentages ranging from 82.71 to 91.33%. The surfaces were mostly cationic with pHpzc ranging from 5.58 to 6.40. Morphological studies by SEM confirmed the crystalline nature of the surfaces which is suitable for adsorption studies. Time-dependent adsorption studies show that C1 is a good candidate for the adsorption of chlorophenols, methyl orange, and Eriochrome Black T.

scholarly journals Novel Bovine Serum Albumin Protein Backbone Reassembly Study: Strongly Twisted β-Sheet Structure Promotion upon Interaction with GO-PAMAM

Polymers ◽  
2020 ◽  
Vol 12 (11) ◽  
pp. 2603
Author(s):  
Andra Mihaela Onaș ◽  
Iuliana Elena Bîru ◽  
Sorina Alexandra Gârea ◽  
Horia Iovu
Keyword(s):  
Secondary Structure ◽  
Bovine Serum Albumin ◽  
Serum Albumin ◽  
Bovine Serum ◽  
Infrared Spectrometry ◽  
X Ray Diffraction ◽  
Protein Backbone ◽  
Raman Spectrometry ◽  
X Ray ◽  
Β Sheet

This study investigates the formation of a graphene oxide-polyamidoamine dendrimer complex (GO-PAMAM) and its association and interaction with bovine serum albumin (BSA). Fourier-transform infrared spectrometry and X-ray photoelectron spectrometry indicated the formation of covalent linkage between the GO surface and PAMAM with 7.22% nitrogen content in the GO-PAMAM sample, and various interactions between BSA and GO-PAMAM, including π-π* interactions at 291.5 eV for the binding energy value. Thermogravimetric analysis highlighted the increasing thermal stability throughout the modification process, from 151 to 192 °C for the 10% weight loss temperature. Raman spectrometry and X-ray diffraction analysis were used in order to examine the complexes’ assembly, showing a prominent (0 0 2) lattice in GO-PAMAM. Dynamic light scattering tests proved the formation of stable graphenic and graphenic-protein aggregates. The secondary structure rearrangement of BSA after interaction with GO-PAMAM was investigated using circular dichroism spectroscopy. We have observed a shift from 10.9% β-sheet composition in native BSA to 64.9% β-sheet composition after the interaction with GO-PAMAM. This interaction promoted the rearrangement of the protein backbone, leading to strongly twisted β-sheet secondary structure architecture.

A lithium-bearing aluminian regular mixed layer montmorillonite-chlorite from Huy, Belgium

Clay Minerals ◽  
1974 ◽  
Vol 10 (3) ◽  
pp. 135-144 ◽  
Author(s):  
G. Brown ◽  
P. Bourguignon ◽  
J. Thorez
Keyword(s):  
Mixed Layer ◽  
Cation Exchange Capacity ◽  
Structural Formula ◽  
Exchange Capacity ◽  
X Ray Diffraction ◽  
X Ray ◽  
Saturated Clay ◽  
Bluish Green ◽  
Image Position ◽  
Green Clay

AbstractA bluish-green clay found in veins cutting across brecciated slates of the Llanvirnian stage at Huy, Belgium, is shown by X-ray diffraction and chemical analysis to be a lithium-bearing, aluminium-rich, regular mixed layer montmorillonite-chlorite with associated pyrophyllite, nacrite and quartz and smaller amounts of calcite and ankerite. The cation exchange capacity of the purified air-dry magnesium saturated clay is 49 mEq/100 g and its structural formula isThe problem of the nomenclature of regular mixed layer montmorillonite-chlorites is discussed.

scholarly journals Aggregation structure characterization of silk fibroin–crosslinking oxidized bamboo pulp fibers

2019 ◽  
Vol 14 ◽  
pp. 155892501989011 ◽  
Author(s):  
Yunxia Wang ◽  
Zhaofang Du ◽  
Liling Zhang ◽  
Yunhui Xu
Keyword(s):  
Electron Microscopy ◽  
Scanning Electron Microscopy ◽  
Silk Fibroin ◽  
Infrared Spectrometry ◽  
Pulp Fiber ◽  
X Ray Diffraction ◽  
Oxidation Treatment ◽  
X Ray ◽  
Bamboo Pulp ◽  
Scanning Electron

Bamboo pulp fiber as one of new promising green fiber was widely used in clothing, medical, automotive, construction, transportation, and many other areas. However, bamboo pulp fiber also has many defects such as larger shrinkage, lower wet strength, fabric wrinkle, and the poor ability to keep type. In this study, a green modification method for bamboo fiber was applied to overcome above-mentioned drawback and verified by scanning electron microscopy, Fourier-transform infrared spectrometry, X-ray diffraction, and solid-state CP/MAS 13C nuclear magnetic resonance respectively. The scanning electron microscopy results showed that oxidation treatment can cause fibers edge damage and denudation after modification, but can introduce the carboxyl groups to C6 position of pure bamboo cellulose macromolecular. The X-ray diffraction results revealed that the fibers’ crystalline structure was not changed throughout the modification process. The oxidation treatment processes can be interpreted as following: amino groups of silk fibroin first react with the carboxyl group and are connected to the fibers though C–N covalent bond, and then a smooth silk fibroin film was formed on the surface of fibers by crosslinking reaction of itself.

Preparation of CuS/SiO2 Composite Modified Aerogel and Its Superoleophobic and Photocatalytic Properties

NANO ◽  
2020 ◽  
Vol 15 (02) ◽  
pp. 2050017
Author(s):  
Ke-Cheng Yang ◽  
Li-Hui Xu ◽  
Hong Pan ◽  
Li-Ming Wang ◽  
Yong Shen ◽  
...  
Keyword(s):  
Gas Adsorption ◽  
Ambient Pressure ◽  
Sol Gel ◽  
Photocatalytic Properties ◽  
X Ray Diffraction ◽  
Sliding Angle ◽  
Nitrogen Gas ◽  
Ir Spectrometry ◽  
X Ray ◽  
Ft Ir

In this study, CuS/SiO2 composite modified aerogel was prepared by the incorporation of hollow spherical CuS into methyltrimethoxysilane-based SiO2 sol and modification with hexadecafluorodecyltriethoxysilane via acid-base catalyzed sol–gel reaction and drying under ambient pressure. The CuS/SiO2 composite modified aerogel was characterized by Fourier-transform infrared (FT-IR) spectrometry, scanning electron microscope (SEM), nitrogen gas adsorption and desorption and X-ray diffraction (XRD), respectively. The effects of CuS and fluorosilane concentration on density and porosity of aerogel, oleophobic and photocatalytic properties were evaluated. The results showed that structure and physical properties of aerogel had some effect by introducing CuS and fluorosilane, and the CuS/SiO2 composite modified aerogel with density of 0.146[Formula: see text]g/cm3 and specific surface area of 241[Formula: see text]m2/g achieved super-oleophobicity with oil contact angle of 152.8∘ and sliding angle of 10∘, and good photocatalytic properties for methylene blue.

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