scholarly journals Improvements in Aggregate-Paste Interface by the Hydration of Steelmaking Waste in Concretes and Mortars

Materials ◽  
2019 ◽  
Vol 12 (7) ◽  
pp. 1147 ◽  
Author(s):  
Isabel Miñano ◽  
Francisco Benito ◽  
Manuel Valcuende ◽  
Carlos Rodríguez ◽  
Carlos Parra
Keyword(s):  
Mechanical Properties ◽  
Chemical Interaction ◽  
Raw Materials ◽  
The Other ◽  
Reaction Products ◽  
Hydrated Calcium Silicate ◽  
Limestone Aggregate ◽  
Other Hand ◽  
The Matrix ◽  
New Compounds

The objective of the experimental work is to study the mechanical properties in self-compacting concretes (SCC) in which part of the limestone aggregate has been replaced by granulated blast furnace slag (GBFS) in different percentages ranging from 0% to 60%. The results show that at early ages the SCC with the largest content in slag tend to have lower compressive strengths due to the poor compacting of the aggregates, although in the long-term their strength increases due to the reactivity of the slag. In fact, at the age of 365 days, the mortars made with the substitution of 50% of cement by ground GBFS reach compressive strength similar to that of the mortar made with 100% of cement. The consumption of calcium hydroxide during the hydration of the GBFS and the formation of hydrated calcium silicate (CSH) improve the mechanical properties of the slag-paste interface. The new compounds formed by the hydration of anhydrous oxides of the GBFS improve the aggregate-paste transition zone. The chemical interaction between the dissolution of the cement pore and the GBFS ends up generating new compounds on its surface. The increasing hydration of the GBFS produces a greater amount of silica gel that polymerises, densifying the matrix and reducing the porosity, which improves the mechanical properties of the concrete and perhaps its durability. The topography of the particles and their interface are analysed with atomic force microscopy techniques to assess the morphology depending on the aggregate used. On the other hand, a study was carried out of the aggregate-paste interface with scanning electronic microscope at different ages. It can be seen that in the contours of the hydrated GBFS particles, a band or ring forms with the new reaction products. The results obtained strengthen the previous conclusions. The new hydrated compounds fill the reaction ring, introducing chemical bonds between the aggregate and the interface, occupying part of the original pores or substituting spaces occupied originally by large portlandite crystals, of lesser mechanical strength and easily leached. For all this, the benefit is twofold. On the one hand, use is made of industrial by-products and, on the other hand, part of the destruction of natural quarries to obtain the necessary raw materials is avoided.

Improvement of Mechanical Properties by Two-Step Aging in Ultrafine Grained Al-Ag-Sc Alloy

2014 ◽  
Vol 794-796 ◽  
pp. 857-863
Author(s):  
Daisuke Terada ◽  
Yan Zeng ◽  
Nobuhiro Tsuji
Keyword(s):  
Mechanical Properties ◽  
Grain Boundaries ◽  
Tensile Elongation ◽  
The Other ◽  
Al Alloy ◽  
Other Hand ◽  
Heat Treated ◽  
Ultrafine Grained ◽  
The Matrix ◽  
The Difference

In order to improve limited ductility of ultrafine grained (UFG) Al alloys, mechanical properties of an UFG Al alloy having fine precipitates within grains were investigated. An Al-0.2wt%Sc-4.2wt%Ag alloy was severely deformed by the ARB process at room temperature and subsequently heat-treated by a two-step aging. After the first aging in the two-step aging, fine Al3Sc precipitates were formed. In the specimen ARB processed by 4cycles, the fine Al3Sc precipitates were homogeneously dispersed within the grains. On the other hand, in the specimen ARB processed by 8 cycles, Al3Sc precipitates were linearly-aligned on the grain boundaries that had moved during the heat treatment. After the second aging, fine G.P. zones of Ag as well as Ag2Al precipitates were observed within the grains in the specimen ARB processed by 4 cycles. Coarse precipitates of Ag2Al at grain boundaries were observed in the specimen ARB processed by 8 cycles. The difference in the distribution of precipitates was considered to be due to the difference in fraction of high angle grain boundaries in the matrix microstructures. The strength of the solution treated specimen increased by the two-step aging while the tensile elongation decreased. On the other hand, both of the strength and elongation of the specimen ARB processed by 4 cycles increased after the two-step aging. In case of the specimen ARB processed by 8 cycles, the strength decreased slightly and the elongation increased by the two-step aging, and the aged specimen exhibited a good balance between strength and elongation.

Selective cyclization modes of methyl 3′-heteroarylamino-2′-(2,5-dichlorothiophene-3-carbonyl)acrylates. Synthesis of model (thienyl)pyrazolo- and triazolo[1,5-α]pyrimidines

2020 ◽  
Vol 75 (12) ◽  
pp. 1037-1042
Author(s):  
Nuha I. Sweidan ◽  
Mustafa M. El-Abadelah ◽  
Musa Z. Nazer ◽  
Wolfgang Voelter
Keyword(s):  
Spectral Data ◽  
The Other ◽  
Keto Group ◽  
Other Hand ◽  
Selective Displacement ◽  
New Compounds

AbstractInteraction of methyl 3-ethoxy-2-(2,5-dichloro-3-thenoyl)acrylate (I) with 3-aminopyrazole and 3-amino-1,2,4-triazole generated the respective pyrazolo[1,5-α]pyrimidine (4) and triazolo[1,5-α]pyrimidine (7). The formation of 4 entails selective and consecutive displacement of the 3-ethoxy and methoxy (ester) anions in I by 3-NH2 and 1-NH of 3-aminopyrazole. On the other hand, the formation of 7 implies selective displacement of 3-ethoxy in I by the ring-NH followed by cyclocondensation involving the keto group in I and 3-NH2 of aminotriazole. This latter selective displacement sequence is also followed by 3-amino-5-hydroxypyrazole in its reaction with I. The structures of the new compounds are supported by microanalytical and spectral data.

New uses for brick-making clay materials from the Bailén area (southern Spain)

Clay Minerals ◽  
1998 ◽  
Vol 33 (3) ◽  
pp. 453-465 ◽  
Author(s):  
I. Gonzalez ◽  
E. Galan ◽  
A. Miras ◽  
P. Aparicio
Keyword(s):  
Particle Size ◽  
Iron Oxides ◽  
Raw Materials ◽  
The Other ◽  
Southern Spain ◽  
Other Hand ◽  
Floor Tiles ◽  
Potential Applications ◽  
Clay Materials

AbstractAn attempt has been made to assess new potential applications for the Bailén clays, traditionally used for manufacturing bricks, based on mineralogical, chemical, particle size, plasticity and firing results. Raw materials and mixtures used by the local factory were selected and tested with the addition of some diatomite, feldspar or kaolin. Based on their properties, clay materials from Bailén might be suitable for making porous red wall tiles, clinker, vitrified red floor tiles and porous light-coloured wall tiles by pressing; the first could be manufactured from the raw materials and mixtures currently used by the local manufactures. On the other hand, stoneware shaped by extrusion, such as perforated bricks, facing bricks and roofing tiles, can be also manufactured from the mixtures used at the factory if they contain 20-25% carbonate and small amounts of iron oxides; lightweight bricks require black and yellow clays with diatomite.

scholarly journals Biological Tools to Deal with Pollution : Selected Advances and Novel Perspectives

2014 ◽  
Vol 3 (1) ◽  
pp. 57
Author(s):  
Abdelaziz Ghanemi ◽  
Besma Boubertakh
Keyword(s):  
Public Health ◽  
Raw Materials ◽  
Economic Benefits ◽  
The Other ◽  
Environment And Public Health ◽  
The Public ◽  
Other Hand ◽  
Metabolic Properties ◽  
Living Organisms ◽  
The Impact

Pollution  represents  a  problem  common  to economy and  public  health. Indeed, the public health, because of the  divers’  type of pollutions, is facing divers challenges for which urgent solutions are required.The biology provides approaches not only to deal with the pollution, but also to  obtain  economic  benefits. Some living  organisms  have  particular metabolisms  that allow  them  to  assimilate  and  metabolite  the polluting agents  and thus reduce the  impact  they have on both environment  and public health.  On  the other  hand,  the  metabolic  properties  of  specific organisms make  the  polluting  elements raw materials to  synthesize  other elements that are benefits  for  economy  and  non-toxic  for  the  ecology and  the  biohealth. Yet, other options such as the regulations and laws are  required  to improve the efficiency of these approaches.

Morphology and mechanical properties of transcrystalline isotactic polypropylene

e-Polymers ◽  
2003 ◽  
Vol 3 (1) ◽  
Author(s):  
Koh-hei Nitta ◽  
Yoshikazu Yamamoto
Keyword(s):  
Mechanical Properties ◽  
Isotactic Polypropylene ◽  
Mechanical Energy ◽  
Supermolecular Structure ◽  
The Other ◽  
Morphological Properties ◽  
Spherulitic Morphology ◽  
Other Hand ◽  
Morphology And Mechanical Properties ◽  
Yielding Process

Abstract We examined mechanical and morphological properties of fully transcrystalline polypropylene grown from the surface of poly(tetrafluoroethylene) sheets. Comparison of mechanical properties between transcrystalline and spherulitic polypropylenes demonstrated that Young’s modulus is dependent on the crystallinity and independent of the supermolecular structure. On the other hand, the mechanical yielding process was predominantly affected by the supermolecular structure, and the mechanical energy required for yielding of transcrystalline sheets was greater than that of the spherulitic morphology. In addition, it was found that mechanical necking is required for the alignment of lamellae in the stretching direction. This means that the unfolding process of lamellae orienting in the stretching direction is associated with necking and ductility.

A French place without a cheese

Focaal ◽  
2004 ◽  
Vol 2004 (44) ◽  
pp. 72-86 ◽  
Author(s):  
Paola Filippucci
Keyword(s):  
Public Policy ◽  
Cultural Heritage ◽  
Raw Materials ◽  
The Other ◽  
Other Hand ◽  
Local Product ◽  
Definition Of

In France, the classic produit du terroir, the local product that with its mix of skill and raw materials embodies the distinctive tie between people and their terroir (soil), is cheese. Thus, when inhabitants of the Argonne say that it “does not even have a cheese”, they imply that it lacks a patrimoine (cultural heritage). On the other hand, they do make passionate claims about 'being Argonnais', conveying a marked recognition of, and attachment to, a named place in relation to which they identify themselves and others. Focusing on this paradox, this article will highlight certain assumptions regarding the definition of cultural heritage found in public policy.

Phenomena of the Mechanical Deformation of Rubber

1931 ◽  
Vol 4 (1) ◽  
pp. 54-63
Author(s):  
H. Mark ◽  
E. Valko
Keyword(s):  
Mechanical Properties ◽  
Single Crystal ◽  
Mechanical Deformation ◽  
The Other ◽  
Considerable Progress ◽  
Organic Substances ◽  
Normal Position ◽  
Regular Lattice ◽  
Other Hand ◽  
Crystalline System

Abstract It is only during recent years that it has become possible by the use of new technic to detect molecular phenomena produced in the mechanical deformation of substances. As far as metallic substances are concerned, and crystalline substances in particular, the problem has already been solved for the most part. On the other hand, in spite of considerable progress during recent years the study of the deformation of organic substances and of fibers in particular, in which group rubber is included, has not yet been carried on. The mechanical properties of a crystalline system vary according to whether there is a single crystal or an aggregate of crystals. However, in both cases the extensibility of the products originates in a displacement of parallel layers, i. e., a sliding of the parts of the crystal along definite crystalline planes, this phenomenon of sliding being irreversible in these substances. In fact, in these cases the reversible part of the elongation is very weak, and amounts to only a few thousandths of the entire phenomenon. In brief, the phenomena of hardening brought about by deformation (sometimes observable) are due to disturbances of the regular lattice. In particular, the displacement of the atom and the change from its normal position can cause the appearance of irregularities on the surface of sliding.

Adverbial clauses and V3

2019 ◽  
Vol 5 (s3) ◽  
Author(s):  
Eva Csipak
Keyword(s):  
Word Order ◽  
Speech Act ◽  
The Other ◽  
Order Effects ◽  
Matrix Clause ◽  
Other Hand ◽  
Pragmatic Analysis ◽  
The Matrix ◽  
Adverbial Clauses ◽  
Biscuit Conditionals

AbstractThis paper discusses word order effects in German adverbial clauses: often, the matrix clause can exhibit either V2 or V3 word order. I argue that adverbial clauses with V3 word order have an obligatory ‘biscuit’ interpretation and receive a speech act modifying interpretation, as has previously only been argued for ‘biscuit conditionals’. I show that this phenomenon holds more generally. On the other hand, a pragmatic analysis for V2 biscuit conditionals remains necessary.

Effect of Fiber Size on Mechanical and Water Absorption Properties of Recycled Polypropylene/Empty Fruit Bunches (rPP/EFB) Bio-Composites

2016 ◽  
Vol 842 ◽  
pp. 7-13 ◽  
Author(s):  
Ozi Adi Saputra ◽  
Ludfiaastu Rinawati ◽  
Kartika Setia Rini ◽  
Dheo Adha Saputra ◽  
Edi Pramono
Keyword(s):  
Mechanical Properties ◽  
Water Absorption ◽  
Chemical Interaction ◽  
Raw Materials ◽  
Short Fiber ◽  
Wave Number ◽  
Empty Fruit Bunch ◽  
Absorption Properties ◽  
Recycled Polypropylene ◽  
Fiber Size

The influence of fiber size on mechanical and water absorption properties of recycled Polypropylene/Palm Empty Fruit Bunch (namely, rPP/EFB) bio-composites has been conducted study. rPP/EFB bio-composite was a compounding of recycled polypropylene (rPP) and palm empty fruit bunch (EFB) with different sizes, i.e. particle size (150 mesh sieve escaped, referred as p-EFB) and short fiber (s-EFB). Manufacturing of the bio-composites was prepared by the solution method in boiling xylene via reactively process using benzoyl peroxide as an initiator. The addition of coupling agent, such as maleic anhydride grafted polypropylene (PP-g-MAH) was improve the chemical interaction between the rPP and EFB which evidenced by the shift of the wave number of raw materials on infra-red spectra of rPP/EFB bio-composite. Mechanical properties test showed that s-EFB was increase the tensile strength value up to 95% compare to rPP, higher than the p-EFB which is 56% compare to rPP. However, the elongation percentage of the bio-composites contain s-EFB was lower than the bio-composites contain p-EFB. Water absorption analysis also performed in this study to determine the biodegradability of bio-composites. In this study, fiber size gives a considerable influence on the mechanical properties of rPP/EFB bio-composites, however not significant on water absorption properties.

Effect of Weld Side Combination on Mechanical Properties of Double Sided Friction Stir Welded 5083 Aluminum Alloy

2014 ◽  
Vol 699 ◽  
pp. 169-174
Author(s):  
Achmad Zubaydi ◽  
Nurul Muhayat ◽  
Budie Santosa ◽  
Dony Setyawan
Keyword(s):  
Mechanical Properties ◽  
Aluminum Alloy ◽  
Tensile Properties ◽  
Welded Joints ◽  
Welding Process ◽  
The Other ◽  
Butt Welds ◽  
Friction Stir ◽  
Other Hand ◽  
5083 Aluminum Alloy

Double sided friction stir butt welds on 6 mm thick of 5083 aluminum alloy were produced. Two variants of the weld side combination, different weld side (DS) and same weld side (SS), have been made to investigate the effect of the weld side on mechanical properties.The SS is a double sided welding process that produces advancing side in one plate and retreating side in the other one. On the other hand, the DS is a double sided welding process that causes advancing side and retreating side in each plate. Tensile properties of the joints were evaluated and correlated with macrostructure and hardness. The weld side influenced the macrostructure and mechanical properties of welded joints. The different weld side (DS) had better mechanical properties than the same weld side (SS).

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