Processing of an in-situ Layered and Graded Alumina/Calcium-Hexaluminate composite: Physical Characteristics

1998 ◽  
Vol 18 (14) ◽  
pp. 2019-2024 ◽  
Author(s):  
D. Asmi ◽  
I.M. Low
Keyword(s):  
Physical Characteristics ◽  
Calcium Hexaluminate

scholarly journals GENESIS AND PHYSICAL CHARACTERISTICS OF THE NEOGENE RED BEDS FROM THE CEDARHILS OF THESSALONIKI, MACEDONIA , GREECE

2018 ◽  
Vol 36 (2) ◽  
pp. 708 ◽  
Author(s):  
A. Tsirambides
Keyword(s):  
Clay Minerals ◽  
Urban Forest ◽  
Clay Fraction ◽  
Eastern Mediterranean Region ◽  
Physical Characteristics ◽  
Coarse Grained ◽  
Red Beds ◽  
Primary Minerals ◽  
In Situ Weathering

The genesis and the physical characteristics of the Neogene red beds of the cedar hills surrounding Thessaloniki are studied in this paper. The peri-urban forest, which covers these hills, has a 3,022 ha area. The topographic relief is smooth and is divided in eight small drainage basins, tapped through small creeks. The elevation of the surrounding hills varies between 85 and 560 m. The dominant land slopes vary between 20 and 55%. All the samples are coarse grained, poorly sorted and friable and present earthy lustre and red colour because of the extensive presence of iron oxides. Angular to sub-angular rock fragments derived from the metamorphic bedrock are very common. Petrographically, the studied red beds belong to the clayey sands. The extended presence (41-66%) of coarse silt and sand size grains (>20 pm) in the samples suggests a mild intensity of in situ weathering of the bedrock. X-ray diffraction analysis of the coarsest fractions 250-20 pm and 20-2 μιτι revealed in decreasing abundance the presence of quartz, feldspars, epidote, micas, chlorite, pyroxenes, amphiboles, and talc. These fractions contain the 2M polytype of mica, while in the fraction <2 pm the 1Μα polytype of illite predominates. In the clay fraction (<2 pm) illite, smectite, and chlorite predominate. The presence of mixed-layer minerals is limited, testifying the almost complete character of hydrolysis of the primary minerals. The formation of red beds took place on low relief land under alternating wet and dry seasons, which prevail in the eastern Mediterranean region since Neogene. The clay minerals are the in situ weathering products of the primary minerals of the greenschists, gneisses and gabbros predominating in the studied area. The extensive presence of clay size grains (11-26%) in the samples, their poor sorting, and their sub-angular morphology, indicate that the red beds are texturally immature. In addition, the abundance of feldspars and Fe-Mg minerals reflects mineralogical immaturity. The low relief and the long-lasting tectonic stability in the Thessaloniki district were essential for the significant thickness of the red beds. The oxygen isotope data of the <0.2 pm fraction (+18.2 to +18.8%o) confirm the pedogenic origin of the clay minerals present. The red beds studied present low plasticity with liquid limit (WÏ) 26.9 to 33.4% and plasticity index (lp) 9.1 to 17.3%. In addition, they have high consolidation index (lc) values (1.03 to 2.28). The swelling potential is low to medium and the activity varies between 0.5 and 1.0. The consolidation and induration degree of the samples analyzed is low, because of the great range of their mineralogical composition and the mild conditions of pressure and temperature to which they have been submitted. The studied red beds are not considered problematic for the foundation of various constructions on them.

Identification of Marine Soils by Ballistic Penetrometry

1990 ◽  
Vol 112 (4) ◽  
pp. 277-284
Author(s):  
O. Hembise ◽  
P. Guevel ◽  
P. R. Bardey ◽  
J. L. Viaud ◽  
J. Y. Boisson ◽  
...  
Keyword(s):  
High Pressure ◽  
Shape Optimization ◽  
Data Acquisition ◽  
Pressure Sensors ◽  
Physical Characteristics ◽  
In Situ Measurements ◽  
Disposable Sensor ◽  
Course Stability

This article describes a disposable, sensor-filled ballistic penetrator for in-situ measurements during and after penetration into the clayey sediments of the seabed at depths of about 6000 m. The project involved work on several theoretical and experimental aspects of hydrodynamics: penetrator shape optimization, course stability, precision of point of impact. In addition, measurement and data acquisition techniques were developed using high-pressure sensors, and the dynamics of soil penetration and hole-closing were studied. The project led to the implementation of instrument-carrying devices weighing two tonnes, which, by penetrating some 40 m into the clay at impact speeds of the order of 55 m/s, provided valuable information on the physical characteristics of the seabed soils.

Tassement et consolidation au dégel d'un silt argileux à Kangiqsualujjuaq

1991 ◽  
Vol 28 (5) ◽  
pp. 678-689
Author(s):  
Serge Leroueil ◽  
Guy Dionne ◽  
Michel Allard
Keyword(s):  
Key Words ◽  
Physical Characteristics ◽  
Pore Pressures ◽  
Clayey Silt ◽  
Excess Pore Pressures ◽  
Excess Pore

The physical characteristics, the compressibility, and the consolidation of a permafrost clayey silt of Kangiqsualujjuaq, Quebec, have been studied, in the laboratory and in the field, by melting the permafrost in the foundation of an excavation. It appears that the values of the thawing settlement parameter (A0) obtained in the laboratory and in the field coincide perfectly with one another, and with those found in the literature for the same type of soil. It has also been observed, on that site, that the thawing of the permafrost, even though ice-rich, does not generate excess pore pressures. Key words: permafrost, compressibility, consolidation, laboratory, in situ. [Journal translation]

scholarly journals Physical Characteristics and Cell-Adhesive Properties of In Vivo Fabricated Hyaluronan/Bacterial Cellulose Nanocomposites

2021 ◽  
Author(s):  
Ryo Takahama ◽  
Honami Kato ◽  
Go Takayama ◽  
Kenji Tajima ◽  
Tetsuo Kondo
Keyword(s):  
Bacterial Cellulose ◽  
Physical Characteristics ◽  
Genetically Engineered ◽  
Basic Material ◽  
Adhesive Properties ◽  
Gluconacetobacter Hansenii ◽  
Modification Technique ◽  
Cellulose Nanocomposites

Abstract This study attempts to clarify the basic material properties of in-vivo-fabricated hyaluronan (HA)/bacterial cellulose (BC) nanocomposites prepared previously. BC membranes (pellicles) generated by Gluconacetobacter hansenii (G. hansenii) are promising biomaterials owing to their outstanding biocompatible properties. Recently, specific demands for biomedical applications of BC have increased owing to its excellent mechanical properties. Although many techniques have been developed to improve the biofunctional properties of BC pellicles, such modifications remain limited owing to technical difficulties in the modulation of complex biosynthetic processes. Therefore, we previously developed an in vivo modification technique to produce nanocomposite pellicles composed of BC and HA (in vivo HA/BC), which are directly secreted from genetically engineered G. hansenii. In the present study, the HA extractability and content rate, physical characteristics, and cytocompatibility of in vivo HA/BC have been investigated in comparison to conventional in situ HA/BC and native BC pellicle. The results suggested that HA more strongly adsorbed to the solid BC surface of in vivo HA/BC than that of in situ HA/BC, which possibly affected the dynamic viscoelastic characteristics. Furthermore, in vivo HA/BC showed remarkably high human epidermal cell adhesion. These results indicate the great potential of in vivo modification to expand the usefulness of BC-based biomaterials.

Physically effectiveness of beet pulp in dairy cows 1: physical characteristics, ruminal kinetics of nutrients degradation, hydration, and functional specific gravity

2007 ◽  
Vol 2007 ◽  
pp. 215-215
Author(s):  
Teimouri Yansari Asadollah
Keyword(s):  
Particle Size ◽  
Specific Gravity ◽  
Physical Characteristics ◽  
Particle Size Measurement ◽  
Effective Factor ◽  
Beet Pulp ◽  
Water Holding ◽  
Kinetics Of

Some physical properties including particle size, functional specific gravity (FSG; Teimouri Yansari et al., 2004), hydration rate, water holding capacity (WHC) and ionion-cation exchange (Van Soest, 1994) influenced on physically effective factor (pef), but only particle size measurement is central to all effective fibre systems. The objective of this study was to evaluate the effects of three types of beet pulp (BP) on physical characteristics including bulk density, particle size, kinetics of hydration, FSG, WHC, and intrinsic osmotic pressure that measured usingin vitroandin situmethods.

Some remarks on the Iceman: his death and his social rank

2014 ◽  
Vol 89 (1) ◽  
Author(s):  
Paul Gleirscher
Keyword(s):  
High Altitude ◽  
Interdisciplinary Research ◽  
Armed Conflict ◽  
Social Rank ◽  
Physical Characteristics ◽  
Relation Directe

Zahlreiche Untersuchungen an Mumie, Bekleidung und Ausrüstung sowie Ausgrabungen am Fundort haben in den vergangenen zwanzig Jahren eine Fülle von Daten zum Mann aus dem Eis („Ötzi“) erbracht. In der vorliegenden Studie wird insbesondere den interdisziplinär erarbeiteten Daten zum Geschehen um seine Ermordung und um seine soziale Stellung nachgegangen. Dabei zeigt sich, dass alles darauf hinweist, dass der Mann aus dem Eis in einem bereits länger dauernden und in mehreren Facetten fassbaren bewaffneten Konflikt schließlich am Tisenjoch (3210 m ü. NN) gestellt und ermordet wurde. Dabei dürfte die Auffindungsstelle der Leiche als in situ-Befund einzuschätzen sein. Ausrüstung und körperliche Merkmale deuten darauf hin, dass der Mann nicht als Hirte anzusprechen ist, sondern einen höheren sozialen Rang innerhalb seiner Gruppe eingenommen hat. Alle Spekulationen, den Mann als Schamanen, Händler oder Erzsucher zu etikettieren, entbehren ebenso jeder Grundlage wie die Behauptung, dass die Fundstelle Tisenjoch mit der kupferzeitlichen Hochweidnutzung im hinteren Ötztal in einem unmittelbaren Zusammenhang stünde.De nombreuses études sur la momie, les vêtements et l’équipement de l’Homme des Glaces («Ötzi»), ainsi que les fouilles de l’emplacement de sa découverte ont produit une multitude de données au cours des vingt dernières années. L’article présente ici les résultats d’analyses pluridisciplinaires visant à mieux cerner sa mise à mort et son statut social. Il en ressort que tous les éléments disponibles indiquent que l’Homme des Glaces a trouvé la mort au bout d’un long conflit armé, reconnaissable sous différentes facettes, à 3210 m d’altitude sur le Tisenjoch. Il faut ainsi interpréter l’endroit de la découverte de la momie comme découverte in situ. L’équipement et les signes particuliers de l’homme suggèrent qu’il n’était pas berger; au contraire, il provenait d’une couche sociale élevée au sein de son groupe. Toutes les spéculations sur cet individu, qu’il soit chaman, colporteur ou prospecteur sont sans fondement, ainsi que l’affirmation que le lieu de découverte sur le Tisenjoch aurait été en relation directe avec l’exploitation d’alpages dans la haute vallée de l’Ötz au courant de l’âge du cuivre.Twenty years of research on the mummified remains, clothing and equipment of the Iceman (‘Ötzi’),along with the excavations of the site, have generated a mass of data. The aim of this synthesis is to present the circumstances of the murder of this man and determine his social rank from the results obtained by interdisciplinary research. We conclude that the Iceman appears to have been involved in an armed conflict, which had taken place over a period of time and which is manifested in several facets. This conflict ended on the Tisenjoch (3210 m asl) where the Iceman was murdered. The site of the body’s discovery seems to be a feature that was in situ. The Iceman’s equipment and physical characteristics indicate that he was not a shepherd but occupied a higher social rank within his group. Attempts at classifying the Iceman as a shaman, a trader or an ore prospector are entirely unfounded, as is the thesis that the location of the discovery of the Iceman was connected to the exploitation of high-altitude pastures in the upper Ötztalvalley.

In situ measurements of the physical characteristics of Titan's environment

Nature ◽  
2005 ◽  
Vol 438 (7069) ◽  
pp. 785-791 ◽  
Author(s):  
M. Fulchignoni ◽  
F. Ferri ◽  
F. Angrilli ◽  
A. J. Ball ◽  
A. Bar-Nun ◽  
...  
Keyword(s):  
Physical Characteristics ◽  
In Situ Measurements

scholarly journals Inversion for Physical Characteristics of Snow using Passive Radiometric Observations

1982 ◽  
Vol 28 (98) ◽  
pp. 179-185 ◽  
Author(s):  
S. R. Rotman ◽  
A. D. Fisher ◽  
D. H. Staelin
Keyword(s):  
Empirical Method ◽  
Snow Accumulation ◽  
Physical Characteristics ◽  
Accumulation Rates ◽  
Microwave Spectrometer ◽  
Semi Empirical

AbstractThe Nimbus-6 Satellite’s Scanning Microwave Spectrometer (SCAMS) mapped the terrestrial surface continuously for eleven months at 22.2 and 31.6 GHz. A semi-empirical method was devised to process these observations of Greenland and Antarctica and to infer long-term snow accumulation rates; comparison with in situ data suggests the method is generally successful except in certain locations where re-melting is more likely.

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