scholarly journals Anatomy of intergrowth of florencite and xenotime crystals with oscillatory zoning from veins of the Svodovy Au-REE occurrence, Subpolar Urals

2020 ◽  
pp. 26-43
Author(s):  
S.A. Repina ◽  
V.A. Muftakhov
Keyword(s):  
Internal Structure ◽  
Original Method ◽  
Oscillatory Zoning ◽  
Subpolar Urals ◽  
Mineral Aggregates

The morphology and anatomy of a paragenetic intergrowth of REE minerals (xenotime and forencite) from veins of Svodovy Au-REE occurrence (Subpolar Urals) are described. The sequence of crystallization of minerals is identifed using the features of internal structure of individuals and aggregates: surfaces of diferent types, sector boundaries and oscillatory, trend and sectorial zoning. Evidence for a HREE-to-LREE directive crystallization of REE phosphates is given. The linear and volumetric rates of face growth are analyzed. The mechanisms of crystal growh and formation of zoning and surfaces of joint growth of sectors of diferent faces are discussed. The crystals are studied using an original method of analysis of mineral aggregates with oscillatory zoning. Figures 9. Tables 2. References 21.

X-ray microtomography

1988 ◽  
Vol 46 ◽  
pp. 998-999
Author(s):  
H.W. Deckman ◽  
B.F. Flannery ◽  
J.H. Dunsmuir ◽  
K.D' Amico
Keyword(s):  
Computed Tomography ◽  
Internal Structure ◽  
Imaging Technique ◽  
Three Dimensional ◽  
Tissue Structure ◽  
Individual Element ◽  
X Ray ◽  
Non Invasive ◽  
Panoramic Imaging ◽  
Three Dimensional Images

We have developed a new X-ray microscope which produces complete three dimensional images of samples. The microscope operates by performing X-ray tomography with unprecedented resolution. Tomography is a non-invasive imaging technique that creates maps of the internal structure of samples from measurement of the attenuation of penetrating radiation. As conventionally practiced in medical Computed Tomography (CT), radiologists produce maps of bone and tissue structure in several planar sections that reveal features with 1mm resolution and 1% contrast. Microtomography extends the capability of CT in several ways. First, the resolution which approaches one micron, is one thousand times higher than that of the medical CT. Second, our approach acquires and analyses the data in a panoramic imaging format that directly produces three-dimensional maps in a series of contiguous stacked planes. Typical maps available today consist of three hundred planar sections each containing 512x512 pixels. Finally, and perhaps of most import scientifically, microtomography using a synchrotron X-ray source, allows us to generate maps of individual element.

The internal structure of medullated wool

1984 ◽  
Vol 42 ◽  
pp. 388-389
Author(s):  
Leo Barish
Keyword(s):  
Light Microscopy ◽  
Internal Structure ◽  
Wool Fiber ◽  
Guard Hair ◽  
Bright Field ◽  
Wool Fibers ◽  
Thin Skin ◽  
Air Pockets

Although most of the wool used today consists of fine, unmedullated down-type fibers, a great deal of coarse wool is used for carpets, tweeds, industrial fabrics, etc. Besides the obvious diameter difference, coarse wool fibers are often medullated.Medullation may be easily observed using bright field light microscopy. Fig. 1A shows a typical fine diameter nonmedullated wool fiber, Fig. IB illustrates a coarse fiber with a large medulla. The opacity of the medulla is due to the inability of the mounting media to penetrate to the center of the fiber leaving air pockets. Fig. 1C shows an even thicker fiber with a very large medulla and with very thin skin. This type of wool is called “Kemp”, is shed annually or more often, and corresponds to guard hair in fur-bearing animals.

TEM/AEM characterization of fine-grained clay minerals in very-low-grade rocks: Evaluation of contamination by empa involving celadonite family minerals

1996 ◽  
Vol 54 ◽  
pp. 694-695
Author(s):  
Gejing Li ◽  
D. R. Peacor ◽  
D. S. Coombs ◽  
Y. Kawachi
Keyword(s):  
Electron Microscopy ◽  
Volcanic Rocks ◽  
Analytical Electron Microscopy ◽  
Metamorphic Rocks ◽  
New Mineral ◽  
Chemical Compositions ◽  
Low Grade ◽  
Fine Grained ◽  
Depth Analysis ◽  
Mineral Aggregates

Recent advances in transmission electron microscopy (TEM) and analytical electron microscopy (AEM) have led to many new insights into the structural and chemical characteristics of very finegrained, optically homogeneous mineral aggregates in sedimentary and very low-grade metamorphic rocks. Chemical compositions obtained by electron microprobe analysis (EMPA) on such materials have been shown by TEM/AEM to result from beam overlap on contaminant phases on a scale below resolution of EMPA, which in turn can lead to errors in interpretation and determination of formation conditions. Here we present an in-depth analysis of the relation between AEM and EMPA data, which leads also to the definition of new mineral phases, and demonstrate the resolution power of AEM relative to EMPA in investigations of very fine-grained mineral aggregates in sedimentary and very low-grade metamorphic rocks.Celadonite, having end-member composition KMgFe3+Si4O10(OH)2, and with minor substitution of Fe2+ for Mg and Al for Fe3+ on octahedral sites, is a fine-grained mica widespread in volcanic rocks and volcaniclastic sediments which have undergone low-temperature alteration in the oceanic crust and in burial metamorphic sequences.

The German Post-Critical Belief Scale: Internal and External Validity

2003 ◽  
Vol 34 (4) ◽  
pp. 219-226 ◽  
Author(s):  
Bart Duriez ◽  
Claudia Appel ◽  
Dirk Hutsebaut
Keyword(s):  
Internal Structure ◽  
Present Article ◽  
External Validity ◽  
German Version ◽  
Dutch Version ◽  
German Sample ◽  
Belief Scale ◽  
Internal And External Validity

Abstract: Recently, Duriez, Fontaine and Hutsebaut (2000) and Fontaine, Duriez, Luyten and Hutsebaut (2003) constructed the Post-Critical Belief Scale in order to measure the two religiosity dimensions along which Wulff (1991 , 1997 ) summarized the various possible approaches to religion: Exclusion vs. Inclusion of Transcendence and Literal vs. Symbolic. In the present article, the German version of this scale is presented. Results obtained in a heterogeneous German sample (N = 216) suggest that the internal structure of the German version fits the internal structure of the original Dutch version. Moreover, the observed relation between the Literal vs. Symbolic dimension and racism, which was in line with previous studies ( Duriez, in press ), supports the external validity of the German version.

Minimally Invasive Repair of Pectus Excavatum (MIRPE) - The Basel Experience

Swiss Surgery ◽  
2003 ◽  
Vol 9 (6) ◽  
pp. 289-295 ◽  
Author(s):  
Haecker ◽  
Bielek ◽  
von Schweinitz
Keyword(s):  
Minimally Invasive ◽  
Pectus Excavatum ◽  
Pulmonary Function Tests ◽  
Preoperative Evaluation ◽  
Skin Incision ◽  
Original Method ◽  
Restrictive Lung Disease ◽  
Cardiac Compression ◽  
Cardiac Evaluation ◽  
Indications For Operation

Purpose: Minimally invasive repair of pectus excavatum (MIRPE) was first reported in 1998 by D. Nuss. This technique has gained wide acceptance during the last 4-5 years. In the meantime, some modifications of the technique have been introduced by different authors. Our retrospective study reports our own experience over the last 36 months and modifications introduced due to a number of complications. Methods: From 3/2000 to 3/2003, 22 patients underwent MIRPE. Patients median age was 15.5 years (10.7 to 20.3 years). Standardised preoperative evaluation included 3D computerised tomography (CT) scan, pulmonary function tests, cardiac evaluation with electrocardiogram and echocardiography, and photo documentation. Indications for operation included at least two of the following: Haller CT index > 3.2, restrictive lung disease, cardiac compression, progression of the deformity and severe psychological alterations. Results: In 22 patients (2 girls, 20 boys) undergoing MIRPE procedure, a single bar was used in 21 patients and two bars in one boy. Lateral stabilisers were fixed with non resorbable sutures on both sides. Overall, postoperative complications occurred in six patients (27.3%). In two patients (9.1%) a redo-procedure was necessary due to bar displacement. An additional median skin incision was performed in two patients to elevate the sternum. Pneumothorax or hematothorax in two patients resulted in routine use of a chest tube on both sides. Long-term favourable results were noted in all patients. Conclusions: The MIRPE procedure is an effective method with elegant cosmetic results. Modifications of the original method help to decrease the complication rate and to accelerate acquirement of expertise.

Internal Structure of the Spanish Adaptation of the Eating Disorder Inventory-3

2012 ◽  
Vol 28 (1) ◽  
pp. 25-31 ◽  
Author(s):  
Paula Elosua ◽  
Alicia López-Jáuregui
Keyword(s):  
Eating Disorders ◽  
Eating Disorder ◽  
Internal Structure ◽  
Internal Consistency ◽  
Clinical Sample ◽  
Temporal Stability ◽  
Second Order ◽  
Order Structure ◽  
Eating Disorder Inventory ◽  
High Internal Consistency

In this study the Eating Disorder Inventory-3 was adapted to Spanish and analyzed the internal psychometric properties of the test in a clinical sample of females with eating disorders. The results showed a high internal consistency of the scores as well as high temporal stability. The factor structure of the scale composites was analyzed using confirmatory factor analysis. The results supported the existence of a second-order structure beyond the psychological composites. The second-order factor showed high correlation with the factor related to eating disorders. Overall, the Spanish version of the EDI-3 showed good psychometric qualities in terms of internal consistency, temporal stability and internal structure.

Sign in / Sign up

Export Citation Format

Share Document