scholarly journals The stratigraphic complexes of a snowpack

2012 ◽  
Vol 53 (61) ◽  
pp. 39-44 ◽  
Author(s):  
N.A. Kazakov ◽  
J.V. Gensiorovskiy ◽  
S.P. Zhiruev ◽  
M.S. Drevilo
Keyword(s):  
Snow Cover ◽  
Structural Transformation ◽  
Formation Process ◽  
Mechanical Characteristics ◽  
Physical Chemical ◽  
Stratification Structure

AbstractSnowpacks can be described as monogenetic rock, where ice is the basic mineral. They can thus be described in terms of a lithologic complex, that is a cluster of different rocks related by formation process or geological era. The stratigraphic complex of snow cover can be cast as a lithologic complex formed in a certain landscape, passing through stages of sedimentation and diagenesis in similar conditions and forming in the same winter a similar spectrum of stratigraphic columns. The stratigraphic complex possesses similar stratification, structure and texture alongside physical, chemical and mechanical characteristics. In landscapes of the same type located in different regions, the same type of stratigraphic complex is formed. The structural transformation of the snowpack is quantitatively described by coefficients of snowpack recrystallization, secondary stratification and texture. Landscape-indicative properties of snowpacks allow the construction of a unified taxonomic scale of stratigraphic complex with a hierarchy of levels: class, subclass, type, subtype and kind.

Obtaining and Characterisation of Starch-Based Edible Films Incorporating Honey, Propolis and Bee Bread

2019 ◽  
Vol 23 (2) ◽  
pp. 193-198
Author(s):  
Monica Mironescu ◽  
Laura Fratila ◽  
Alexandru Hupert ◽  
Ion Dan Mironescu
Keyword(s):  
Water Activity ◽  
Mechanical Characteristics ◽  
Edible Films ◽  
Ash Content ◽  
Colour Intensity ◽  
Sensorial Analysis ◽  
Physical Chemical ◽  
Control Film ◽  
Bee Bread

Abstract This research investigates the physical-chemical, sensorial and mechanical characteristics of starch-based edible films incorporating three types of bee hive products: honey, propolis and bee bread, in concentrations varying from 1% to 3%, reported to starch. The results indicates an increasing of films moisture, water activity, ash content and acidity, in the order: honey<propolis<bee bread, all values increasing with the increasing of hive products percentage into the control film; aw is remaining at very low values, under 0.4. Sensorial analysis indicated honey as the better suited for improving taste and flavour and bee bread for increasing colour intensity of the films; the sensorial characteristics are maintained during 30 days of films storage, in all cases. Compared with the control starch-based film (which is elastic, brittle and hard), the films containing 2% bee hive products are elasto-plastic and more resistant to penetration, the resistance increasing in the order: bee bread<propolis<honey.

Biodegradable Flax Fiber Reinforced Eco-Composites

2014 ◽  
Vol 604 ◽  
pp. 180-183
Author(s):  
Velta Tupureina ◽  
Anda Dzene ◽  
Marcis Dzenis
Keyword(s):  
Formation Process ◽  
Vinyl Alcohol ◽  
Mechanical Characteristics ◽  
Flax Fiber ◽  
Matrix Composition ◽  
Poly Vinyl Alcohol ◽  
Fiber Reinforced ◽  
Casting Technique ◽  
Modified Polymers ◽  
Water Vapour Absorption

Formation process of flax fiber reinforced biocomposites based on waterborne matrix systems from modified polymers - polyhydroxybutyrate, poly (vinyl alcohol) was developed by suspension casting technique. Two kind of flax fiber as reinforcement was employed Latvian variety Vega-2 and flax combing. The correlation between matrix composition, fiber origin, content and mechanical characteristics, water vapour absorption and biodegradability was established. Optimal characteristics of elaborated eco-composites were obtained by use of flax combing with fiber content ~ 30 wt. %.

Physical, Chemical, and Mechanical Characteristics of Polyphenyl Ether

1967 ◽  
Vol 6 (2) ◽  
pp. 81-88 ◽  
Author(s):  
D. R. Wilson ◽  
W. A. Marshall ◽  
R. E. Dolle ◽  
R. J. Benzing
Keyword(s):  
Mechanical Characteristics ◽  
Polyphenyl Ether ◽  
Physical Chemical

Ferrochrome slag aggregate: physical-chemical characteristics and potential use in lightly cemented road bases

2021 ◽  
Vol ahead-of-print (ahead-of-print) ◽  
Author(s):  
Chewe Kambole ◽  
Phil Paige-Green ◽  
Williams Kehinde Kupolati ◽  
Julius Musyoka Ndambuki
Keyword(s):  
Mechanical Characteristics ◽  
National Standards ◽  
Chemical Characteristics ◽  
Test Procedures ◽  
Content Type ◽  
X Ray ◽  
Physical Chemical ◽  
Ferrochrome Slag ◽  
Ferrochrome Slag Aggregate ◽  
Road Bases

Purpose Most developing countries simply dump ferrochrome slag as waste which occupies huge areas of useful land. The purpose of this study is to underscore the significance of reusing ferrochrome slag as a sustainable and eco-friendly road aggregate material, with the added benefits of preventing possible environmental pollution and promoting sustainable mining of non-renewable construction materials. Design/methodology/approach Physical-mechanical characteristics were investigated using various South African National Standards test procedures. Chemical and mineralogical characteristics were evaluated using the X-ray fluorescence and the X-ray diffraction techniques, respectively. The toxicity characteristic leaching procedure test was used to evaluate the slag’s environmental suitability. Using two cement types, cement proportions of 1%, 2% and 3% of the slag aggregate weight mixed with optimum moisture content of the non-treated compacted slag were used to make lightly cemented ferrochrome slag aggregate (LCFSA) composites, subsequently tested for compressive strength. Findings Ferrochrome slag aggregates have excellent physical-mechanical characteristics that conform to international specifications for use in road base construction. The slag can be classified as non-hazardous solid waste. However, in acidic environments, some toxic elements may leach from the slag and pollute the environment. Optimum cement contents of 2.3% (CEM II) and 2.6% (CEM VB) can be mixed with the slag to produce LCFSA for road bases. Originality/value No research was found in literature on the use of LCFSA in road bases. This research, therefore, presents new data on mix design and strength properties of LCFSA as well as some physical-chemical characteristics of coarse ferrochrome slag aggregate.

scholarly journals Snow Forces

1977 ◽  
Vol 19 (81) ◽  
pp. 67-100 ◽  
Author(s):  
Bruno Salm
Keyword(s):  
Snow Cover ◽  
Shear Viscosity ◽  
Mechanical Characteristics ◽  
Slow Motion ◽  
Newtonian Liquid ◽  
Poisson's Ratio ◽  
Total Water ◽  
Probability Of Occurrence ◽  
Seasonal Snow ◽  
Seasonal Snow Cover

AbstractSnow forces are understood as forces originating from a very slow motion of the seasonal snow cover and acting on boundaries confining it. They depend on the total water-equivalent (a statistical magnitude with a certain probability of occurrence) and on mechanical characteristics of snow. The approximation of considering of snow as a Newtonian liquid fits the requirements for applications best. In this the only mechanical characteristics to be taken into account, besides density, are shear viscosity and Poisson’s ratio. They depend strongly on the snow structure. Generalizations are shown in which the snow cover is subdivided into layers having constant (Newtonian) properties. Non-Newtonian behaviour is also mentioned.

scholarly journals Obtaining particulate agglomerates from the recycling of multilayer containers and low density polyethylene

2021 ◽  
pp. 1-6
Author(s):  
Ma. Angeles Enríquez-Pérez ◽  
Jaime Rosales-Davalos ◽  
Víctor Hugo Castrejón-Sánchez
Keyword(s):  
Construction Industry ◽  
Mechanical Characteristics ◽  
Modulus Of Rupture ◽  
Low Density Polyethylene ◽  
Low Density ◽  
Compression Tests ◽  
New Materials ◽  
Physical Chemical ◽  
The One ◽  
Mass Volume

Currently, the interest and the need to innovate new materials through the use of waste materials has grown, which meet similar or improved physical, chemical and mechanical characteristics of the materials they will replace. During the present investigation, Multilayer Containers (EM) and Low Density Polyethylene (LDPE) were collected, particulate agglomerates with different proportions were obtained, the apparent density, water absorption, mass, volume, heat behavior, angle were determined. contact, machining and compression tests. With the objective of evaluating the proportions p / p in the properties. The advantage of the material obtained is that they do not generate waste and are 100% recyclable. The 90:10 ratio is the one that could be used in the construction industry as false walls, with a modulus of rupture of 52.7 N / mm2 and a compressive stress of 32.9 MP, because it can be machined without altering its characteristics. -physical houses; While the 85:15 and 80:20 proportions, since they cannot be machined, could be used as a floating support with a photocatalyst catalyst, due to the fact that these agglomerates have dimensional stability when in contact with water.

scholarly journals Chemical and physico-mechanical characterizations of leather for restoration

2020 ◽  
Author(s):  
Lucretia Miu ◽  
Simona-Maria Paunescu ◽  
Maria-Cristina Micu ◽  
Iulia-Maria Caniola ◽  
Madalina Ignat ◽  
...  
Keyword(s):  
Mechanical Characteristics ◽  
Mechanical Tests ◽  
Shrinkage Temperature ◽  
Physical Chemical ◽  
Physical Examinations ◽  
Multiple Sample ◽  
Historical Leather ◽  
Multiple Chemical ◽  
Standard Tests ◽  
Comprehensive Study

Leather is a complex material mostly consisting of a matrix of collagen, chemically stabilized by various tannins. This matrix, sooner or later undergoes alterations as a consequence of interactions between their structure and environment. A comprehensive study based on multiple chemical and physico-mechanical standard tests regarding leather samples which were artificially aged from 7 to 112 days has been made at 70°C. The behavior in artificial aging of calf leather samples tanned at pilot level with two different vegetal tannins, mimosa and quebracho, were investigated due to its’s similarity to the natural degradation of historical leather samples. Physico-mechanical characteristics of historical leather can be corelated with the high impact of degree of deterioration even though there are no standard regulations. To be able to choose the proper way to achieve compatibility with an appropriate material in the restoration-conservation process, multiple sample characteristic must be known. The condition of historical leather can be assessed by a series of simple visual and physical examinations which determine the flexibility, strength and coherency of the fibers and then correlate these assessments with the condition of leather as determined by various chemical and physical-chemical analyses. Therefore, the following chemical standard tests were made: volatile substances, shrinkage temperature, extractable substances, total soluble substances and the following physico-mechanical tests: tensile strength, elongation at breaking and tear resistance.

scholarly journals New generation of super duplex steels for equipment gas and oil production

2019 ◽  
Vol 121 ◽  
pp. 04007
Author(s):  
Leonid Levkov ◽  
Dmitry Shurygin ◽  
Vladimir Dub ◽  
Konstantin Kosyrev ◽  
Alan Balikoev
Keyword(s):  
Mechanical Characteristics ◽  
Test Results ◽  
Treatment Regimes ◽  
Physical Chemical ◽  
Duplex Steel ◽  
Materials Used ◽  
Heat Treatment Regimes ◽  
New Generation ◽  
Technological Methods ◽  
Duplex Steels

Oil&gas producing industry today is increased production volumes from old deposits on land, offshore and deep-water. The materials used to create modern equipment that meets these trends should be distinguished by increased productivity in conditions of corrosion and high pressure, to ensure trouble-free operation. In such conditions, taking into account the necessary provision of acceptable cost indicators, there is no alternative to duplex steels. Their crystal structure simultaneously allows using the advantages of ferritic and austenitic phases. The report presents the results of using a compositional and technological methods for structure management, the rationale alloying with copper (3.0-3.3%). Application of ESR in the manufacture of steel billets of super duplex steel has demonstrated the ability to simultaneously achieve physical, chemical and structural homogeneity, ensuring high corrosion&mechanical characteristics. The thermodynamic and kinetic conditions for the formation of optimal phase steel composition are determined. Grounded heat treatment regimes, prevent the formation of sigma and psi-phase and contribute to the formation of stable intermetallides (30-300 nm). Based on the test results of “Gazprom-VNIIGAZ” LLC the new steel is recommended for the manufacture of valve bodies and in-vessel internals used in the fields, that containing H2S and CO2 up to 25% in the fluid.

scholarly journals Snow Forces

1977 ◽  
Vol 19 (81) ◽  
pp. 67-100 ◽  
Author(s):  
Bruno Salm
Keyword(s):  
Snow Cover ◽  
Shear Viscosity ◽  
Mechanical Characteristics ◽  
Slow Motion ◽  
Newtonian Liquid ◽  
Poisson's Ratio ◽  
Total Water ◽  
Probability Of Occurrence ◽  
Seasonal Snow ◽  
Seasonal Snow Cover

AbstractSnow forces are understood as forces originating from a very slow motion of the seasonal snow cover and acting on boundaries confining it. They depend on the total water-equivalent (a statistical magnitude with a certain probability of occurrence) and on mechanical characteristics of snow. The approximation of considering of snow as a Newtonian liquid fits the requirements for applications best. In this the only mechanical characteristics to be taken into account, besides density, are shear viscosity and Poisson’s ratio. They depend strongly on the snow structure. Generalizations are shown in which the snow cover is subdivided into layers having constant (Newtonian) properties. Non-Newtonian behaviour is also mentioned.

scholarly journals Synthesis and Characterizations of a Collagen-Rich Biomembrane with Potential for Tissue-Guided Regeneration

2019 ◽  
Vol 13 (03) ◽  
pp. 295-302 ◽  
Author(s):  
Marcos J. Silva ◽  
Carolina P. Gonçalves ◽  
Kleber M. Galvão ◽  
Paulo H. P. D’Alpino ◽  
Fábio D. Nascimento
Keyword(s):  
Mechanical Properties ◽  
Mechanical Characteristics ◽  
Guided Bone Regeneration ◽  
Commercial Products ◽  
Physical Chemical ◽  
Strength And Deformation ◽  
Mechanical Tensile ◽  
Intestinal Submucosa ◽  
Deformation Tests ◽  
Better Than

Abstract Objectives In this study, a collagen-rich biomembrane obtained from porcine ­intestinal submucosa for application in guided bone regeneration was developed and characterized. Then, its biological and mechanical properties were compared with that of commercial products (GenDerm [Baumer], Lumina-Coat [Critéria], Surgitime PTFE [Bionnovation], and Surgidry Dental F [Technodry]). Materials and Methods The biomembrane was extracted from porcine intestinal submucosa. Scanning electron microscopy, spectroscopic dispersive energy, glycosaminoglycan quantification, and confocal microscopy by intrinsic fluorescence were used to evaluate the collagen structural patterns of the biomembrane. Mechanical tensile and deformation tests were also performed. Statistical Analysis  The results of the methods used for experimental membrane characterizations were compared with that obtained by the commercial membranes and statistically analyzed (significance of 5%). Results The collagen-rich biomembrane developed also exhibited a more organized, less porous collagen fibril network, with the presence of glycosaminoglycans. The experimental biomembrane exhibited mechanical properties, tensile strength, and deformation behavior with improved average stress/strain when compared with other commercial membranes tested. Benefits also include a structured, flexible, and ­bioresorbable characteristics scaffold. Conclusions The experimental collagen-rich membrane developed presents physical–chemical, molecular, and mechanical characteristics similar to or better than that of the commercial products tested, possibly allowing it to actively participating in the process of bone neoformation.

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