A MODIFIEDTWIST-SPINNING TECHNOLOGY:THREE-ROVING YARN SPINNING

Ring spinning is one of the oldest and most widely used spinning technology. Recently, many alternative spinning technologies have been introduced. Some of these technologies work on completely different working principle while some of them were developed from conventional system with some modifications. Siro- spun technology which two strands are fed into drafting zone simultaneously is one of the systems that developed from conventional ring spinning. This study focuses on development of three-roving yarn production system that was inspired from siro-spun technology. Roving funnel and delivery cylinder used in siro-spun technology were redesigned for three-roving yarn production and attached on conventional system. Three-roving yarns produced in ring spinning machine were compared with three plied yarns in terms of physical, mechanical and structural properties. For better assessment of this new system, different raw material types were used in yarn production. Results showed that three-roving yarns have better hairiness values and similar mechanical properties for all raw material types. However, unevenness still needs to be improved by further developments on this new system.

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Microstructure and Mechanical Properties of Chromium Carbide Coatings Deposited by Magnetron Sputtering Technique

Defect and Diffusion Forum ◽

10.4028/www.scientific.net/ddf.397.118 ◽

2019 ◽

Vol 397 ◽

pp. 118-124

Author(s):

Linda Aissani ◽

Khaoula Rahmouni ◽

Laala Guelani ◽

Mourad Zaabat ◽

Akram Alhussein

Keyword(s):

Thin Films ◽

Mechanical Properties ◽

Magnetron Sputtering ◽

Structural Properties ◽

Annealing Temperature ◽

Diffusion Mechanism ◽

X Ray Diffraction ◽

Chromium Carbides ◽

X Ray ◽

Mechanical And Structural Properties

From the hard and anti-corrosions coatings, we found the chromium carbides, these components were discovered by large studies; like thin films since years ago. They were pointed a good quality for the protection of steel, because of their thermal and mechanical properties for this reason, it was used in many fields for protection. Plus: their hardness and their important function in mechanical coatings. The aim of this work joins a study of the effect of the thermal treatment on mechanical and structural properties of the Cr/steel system. Thin films were deposited by cathodic magnetron sputtering on the steel substrates of 100C6, contain 1% wt of carbon. Samples were annealing in vacuum temperature interval between 700 to 1000 °C since 45 min, it forms the chromium carbides. Then pieces are characterising by X-ray diffraction, X-ray microanalysis and scanning electron microscopy. Mechanical properties are analysing by Vickers test. The X-ray diffraction analyse point the formation of the Cr7C3, Cr23C6 carbides at 900°C; they transformed to ternary carbides in a highest temperature, but the Cr3C2 doesn’t appear. The X-ray microanalysis shows the diffusion mechanism between the chromium film and the steel sample; from the variation of: Cr, Fe, C, O elements concentration with the change of annealing temperature. The variation of annealing temperature shows a clean improvement in mechanical and structural properties, like the adhesion and the micro-hardness.

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Mechanical and Structural Properties of TiC and TiCN Thin Films Grown by RF Sputtering

MRS Proceedings ◽

10.1557/proc-778-u6.13 ◽

2003 ◽

Vol 778 ◽

Cited By ~ 2

Author(s):

A. Mani ◽

P. Aubert ◽

H. Khodja ◽

P. Houdy

Keyword(s):

Thin Films ◽

Mechanical Properties ◽

Titanium Carbide ◽

Partial Pressure ◽

Compressive Stress ◽

Structural Properties ◽

Rf Sputtering ◽

Maximum Value ◽

Mechanical And Structural Properties ◽

Sputtering Pressure

AbstractTiC and TiCN thin films were deposited by RF sputtering from a TiC target. For TiC thin films, the various sputtering pressure were carried out in order to observe the influence of this parameter on structural and mechanical properties. The experimental results show that a pressure of 1 Pa is necessary to obtain stoichiometric films with <111> texture. Lower pressures induce the formation of distorted titanium carbide, while RBS spectra show that the Ti/C ratio is constant for all these samples. Both the compressive stress and the hardness exhibited a maximum value for the lowest pressures. For TiCN thin films, the composition and the hardness were investigated as function of the N2 partial pressure (PN2 = 3% to 70%).

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Mechanical Properties of the Rabbit Patellar Tendon

Journal of Biomechanical Engineering ◽

10.1115/1.2891392 ◽

1992 ◽

Vol 114 (3) ◽

pp. 332-337 ◽

Cited By ~ 59

Author(s):

N. Yamamoto ◽

K. Hayashi ◽

H. Kuriyama ◽

K. Ohno ◽

K. Yasuda ◽

...

Keyword(s):

Mechanical Properties ◽

Tensile Strength ◽

Structural Properties ◽

Patellar Tendon ◽

Tensile Tests ◽

The Other ◽

Central Portion ◽

Mechanical And Structural Properties ◽

Lateral Portion

The mechanical and structural properties of the patellar tendon fascicle-bone units of rabbit knees were determined by tensile tests, particularly focusing on their local differences. There were no significant differences in the strains measured by a video dimension analyzer among the proximal, middle, and distal regions of the central portion of tendon. The mechanical properties of the medial portion agreed well with those of the central portion. However, significant differences were observed in the tensile strength between the lateral and the other two portions: the tensile strength of the lateral portion was about 16 percent larger than those in the other portions.

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Mechanical and structural properties of graphene-like carbon nitride sheets

RSC Advances ◽

10.1039/c6ra14273g ◽

2016 ◽

Vol 6 (80) ◽

pp. 76915-76921 ◽

Cited By ~ 31

Author(s):

J. M. de Sousa ◽

T. Botari ◽

E. Perim ◽

R. A. Bizao ◽

Douglas S. Galvao

Keyword(s):

Mechanical Properties ◽

Structural Properties ◽

Carbon Nitride ◽

Fracture Dynamics ◽

Mechanical And Structural Properties

Mechanical properties and fracture dynamics of graphene-like CN membranes were investigated.

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Revealing the linear relationship between electrical, thermal, mechanical and structural properties of carbon nanocoils

Physical Chemistry Chemical Physics ◽

10.1039/c8cp01349g ◽

2018 ◽

Vol 20 (19) ◽

pp. 13316-13321 ◽

Cited By ~ 1

Author(s):

Chenghao Deng ◽

Chengwei Li ◽

Peng Wang ◽

Xinwei Wang ◽

Lujun Pan

Keyword(s):

Mechanical Properties ◽

Linear Relationship ◽

Structural Properties ◽

Linear Relationships ◽

Mechanical And Structural Properties

Simple but significant linear relationships among thermal, electrical and mechanical properties are uncovered by experiments.

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Variation in mechanical and structural properties of enamel in primate molars

10.1101/2021.07.05.451217 ◽

2021 ◽

Author(s):

Ian Towle ◽

Thomas Loho ◽

Amira Salem ◽

Carolina Loch

Keyword(s):

Mechanical Properties ◽

Elastic Modulus ◽

Structural Properties ◽

Ct Scanning ◽

Primate Species ◽

Micro Ct ◽

Mineral Density ◽

Structure Variation ◽

Enamel Structure ◽

Mechanical And Structural Properties

Mechanical properties of enamel are known to vary across molar crowns in some primates, but the association of this variation with phylogeny, structural properties and tribological behaviour is not well understood. In this study, 20 molars from a range of primate taxa (n=15) were studied using nanoindentation, micro-CT scanning, and SEM imaging. After micro-CT scanning, teeth were sectioned in the lingual-buccal plane through the mesial cusps. Five positions (buccal lateral, buccal cuspal, occlusal middle, lingual cuspal, lingual lateral) were studied in three locations (inner, middle, outer enamel regions). The results show middle enamel had the highest hardness and elastic modulus values in all positions. 'Non-functional' molar sides (lingual in lower molars and buccal in upper molars) had higher hardness values than their 'functional' counterparts. Increase in prism size was associated with a decrease in hardness in some tooth positions, and mineral density showed a significant relationship with elastic modulus values. Variation in enamel structure variation (e.g., enamel Schmelzmuster, Hunter-Schreger band thickness), may also be crucial in explaining variation in mechanical properties, with decussation zones associated with higher mechanical properties values. Primate enamel is not a homogeneous material, with variation in mechanical and structural properties across the crown likely associated with functional differences and variation in force distribution. Overall structural and mechanical patterns were similar in the primate species studied despite substantial differences in diet, suggesting these properties are potentially evolutionary conserved.

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Incorporation of Iraqi Rocks in the Production of Eco-Friendly Cement Mortar

Engineering and Technology Journal ◽

10.30684/etj.v38i10a.1479 ◽

2020 ◽

Vol 38 (10A) ◽

pp. 1522-1530

Author(s):

Rawnaq S. Mahdi ◽

Aseel B. AL-Zubidi ◽

Hassan N. Hashim

Keyword(s):

Mechanical Properties ◽

Thermal Conductivity ◽

Compressive Strength ◽

Water Absorption ◽

Structural Properties ◽

Mechanical Milling ◽

Cement Mortar ◽

Cement Mortars

This work reports on the incorporation of Flint and Kaolin rocks powders in the cement mortar in an attempt to improve its mechanical properties and produce an eco-friendly mortar. Flint and Kaolin powders are prepared by dry mechanical milling. The two powders are added separately to the mortars substituting cement partially. The two powders are found to improve the mechanical properties of the mortars. Hardness and compressive strength are found to increase with the increase of powders constituents in the cement mortars. In addition, the two powders affect water absorption and thermal conductivity of the mortar specimens which are desirable for construction applications. Kaolin is found to have a greater effect on the mechanical properties, water absorption, and thermal conductivity of the mortars than Flint. This behavior is discussed and analyzed based on the compositional and structural properties of the rocks powders.

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Mechanical and structural properties of Permalloy films on glass and/or Si(111) substrates

Applied Physics A ◽

10.1007/s00339-008-4841-3 ◽

2008 ◽

Vol 94 (2) ◽

pp. 431-436 ◽

Cited By ~ 7

Author(s):

S. U. Jen ◽

Y. T. Chen ◽

N. T. Yang ◽

W. C. Cheng

Keyword(s):

Structural Properties ◽

Mechanical And Structural Properties

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DNA-Guided Assembly for Fibril Proteins

Mathematics ◽

10.3390/math9040404 ◽

2021 ◽

Vol 9 (4) ◽

pp. 404

Author(s):

Alexandru Amărioarei ◽

Frankie Spencer ◽

Gefry Barad ◽

Ana-Maria Gheorghe ◽

Corina Iţcuş ◽

...

Keyword(s):

Computational Model ◽

Structural Properties ◽

Self Assembly ◽

Structural Characteristics ◽

Computational Modelling ◽

Shape Reconstruction ◽

Raw Material ◽

Dna Assembly ◽

Mesh Structure ◽

Elementary Fibril

Current advances in computational modelling and simulation have led to the inclusion of computer scientists as partners in the process of engineering of new nanomaterials and nanodevices. This trend is now, more than ever, visible in the field of deoxyribonucleic acid (DNA)-based nanotechnology, as DNA’s intrinsic principle of self-assembly has been proven to be highly algorithmic and programmable. As a raw material, DNA is a rather unremarkable fabric. However, as a way to achieve patterns, dynamic behavior, or nano-shape reconstruction, DNA has been proven to be one of the most functional nanomaterials. It would thus be of great potential to pair up DNA’s highly functional assembly characteristics with the mechanic properties of other well-known bio-nanomaterials, such as graphene, cellulos, or fibroin. In the current study, we perform projections regarding the structural properties of a fibril mesh (or filter) for which assembly would be guided by the controlled aggregation of DNA scaffold subunits. The formation of such a 2D fibril mesh structure is ensured by the mechanistic assembly properties borrowed from the DNA assembly apparatus. For generating inexpensive pre-experimental assessments regarding the efficiency of various assembly strategies, we introduced in this study a computational model for the simulation of fibril mesh assembly dynamical systems. Our approach was based on providing solutions towards two main circumstances. First, we created a functional computational model that is restrictive enough to be able to numerically simulate the controlled aggregation of up to 1000s of elementary fibril elements yet rich enough to provide actionable insides on the structural characteristics for the generated assembly. Second, we used the provided numerical model in order to generate projections regarding effective ways of manipulating one of the the key structural properties of such generated filters, namely the average size of the openings (gaps) within these meshes, also known as the filter’s aperture. This work is a continuation of Amarioarei et al., 2018, where a preliminary version of this research was discussed.

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Pre-treatments of pre-consumer cotton-based textile waste for production of textile fibres in the cold NaOH(aq) and cellulose carbamate processes

Cellulose ◽

10.1007/s10570-021-03753-6 ◽

2021 ◽

Author(s):

Marjo Määttänen ◽

Maria Gunnarsson ◽

Helena Wedin ◽

Sara Stibing ◽

Carina Olsson ◽

...

Keyword(s):

Mechanical Properties ◽

Raw Material ◽

Textile Waste ◽

Future Studies ◽

Degree Of Polymerisation ◽

Textile Fibres ◽

Cellulose Carbamate ◽

Regenerated Fibres ◽

Inorganic Content

AbstractRecycling of textiles is of importance due to the large amount of waste generated from the increasing consumption and use worldwide. Cotton-rich pre-consumer textiles are considered as potential raw material for production of man-made regenerated fibres, but demands purification from the blends with synthetic fibres as well as the dyes and finishing chemicals. In this study we explore the use of different pre-treatments of pre-consumer textiles to meet specific parameters for production of fibres in the cold NaOH(aq) or cellulose carbamate process. The pre-treatments consisted of different bleaching sequences and were performed on both uncoloured and coloured pre-consumer textiles. For the uncoloured textile, degree of polymerisation and amount of inorganic content was efficiently reduced making the material suitable for both the cold NaOH(aq) and the cellulose carbamate process. In case of the coloured textile, the pre-treatments were able to remove the dye and decrease the inorganic content as well as reduce the degree of polymerisation but only sufficiently enough for production of fibres in the cellulose carbamate process. The work was able to prove a fibre-to-fibre concept while further optimisation of the regeneration steps is expected to improve the mechanical properties of the produced fibres in future studies.

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