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Open access

Marek Idzik

Abstract

Shortening the technological spinning processes, aiming at the reduction in production costs, causes problems with keeping up a high quality of yarn. Of great significance is the use of autolevellers that not only equalize the distribution of fiber linear density but also straighten the fibers and lay them parallel to the product axis. Consequently, they replace the machines eliminated from technological lines and contribute to the improvement in the quality of intermediate products and yarns. Using an example of the cotton combed spinning system, the article presents the analysis of the possibilities of using a short-term autoleveller with a modified operation algorithm that takes into account the phenomenon of sliver retardation after the process of short-term regulation. The regulation of draft was used before and after combing. The quality parameters of slivers used for feeding roving frames or rotor spinning machines were analyzed.

Open access

Hanen Ghanmi, Adel Ghith and Tarek Benameur

Abstract

This article provides three models to predict rotor spun yarn characteristics which are breaking strength, breaking elongation and unevenness. These models used noncorrelated raw material characteristics and some processing parameters. For this purpose, five different cotton blends were processed into rotor spun yarns having different metric numbers (Nm10, Nm15, Nm18, Nm22, Nm30 and Nm37). Each count was spun at different twist levels. Response surface method was used to estimate yarn quality characteristics and to study variable effects on these characteristics. In this study, predicting models are given by the analysis of response surface after many iterations in which nonsignificant terms are excluded for more accuracy and precision. It was shown that yarn count, twist and sliver properties had considerable effects on the open-end rotor spun yarn properties. This study can help industrial application since it allows a quality management-prediction based on input variables such as fibre characteristics and process parameters.

Open access

Nils-Peter Nilius, Nikolaus Froitzheim, Thorsten Joachim Nagel, Frank Tomaschek and Alexander Heuser

Abstract

The Alpine nappe stack in the Penninic-Austroalpine boundary zone in the Rätikon (Austria) contains a 4×1 km tectonic sliver of meta-diorite, known as the Schwarzhorn Amphibolite. It was deformed and metamorphosed in the amphibolite facies and is unconformably overlain by unmetamorphic Lower Triassic sandstone, indicating pre-Triassic metamorphism. Cataclastic deformation and brecciation of the amphibolite is related to normal faulting and block tilting during Jurassic rifting. Zircon dating of the Schwarzhorn Amphibolite using LA-ICP-MS gave a U-Pb age of 529+9/-8 Ma, interpreted as the crystallization age of the protolith. Geochemical characteristics indicate formation of the magmatic protolith in a supra-subduction zone setting. The Cambrian protolith age identifies the Schwarzhorn Amphibolite as a pre-Variscan element within the Austroalpine basement. Similar calc-alkaline igneous rocks of Late Neoproterozoic to Early Cambrian age are found in the Upper Austroalpine Silvretta Nappe nearby and in several other Variscan basement units of the Alps, interpreted to have formed in a peri-Gondwanan active-margin or island-arc setting.

Open access

Eva Moučková, Iva Mertová, Petra Jirásková, Gabriela Krupincová and Dana Křemenáková

Abstract

This paper analyzes the relationship between technological parameters of spinning of 100% CV Vortex yarns of different counts and its selected geometrical parameters (a lead of helix of wrapping fibre ribbon, yarn diameter) as well as yarn properties. The number of twist of wrapping fibre layer is determined. The effect of the yarn delivery speed, hollow spindle diameter, and the main draft on the hairiness, mass irregularity, tenacity, elongation, resistance to abrasion and bending rigidity of Vortex yarn is observed. The yarn properties are compared with the properties of open-end rotor spun yarns. Slivers of the same spinning lot were used for the production of both kinds of yarn. The results showed that the delivery speed in combination with spindle diameter affects yarn diameter, hairiness and abrasion resistance. Mass irregularity and imperfections of yarn is mainly affected by the main draft of drafting unit. Technological parameters of spinning do not affect the level of bending rigidity of the Vortex yarn. Tested rotor spun yarns had a larger diameter, higher hairiness, lower tenacity and higher elongation, lower mass irregularity and number of imperfections, higher abrasion resistance and lower bending rigidity compared to tested Vortex spun yarns.

Open access

Mohammad Hatamvand, Seyed Abbas Mirjalili, Saeid Fattahi, Tariq Bashir and Mikael Skrifvars

the Spinning Properties of Man-made Staple fibers. Textile Research Journal, 28, 819-839. [5] Audivert, R. (1974). The Relation between the Drafting Force, Draft, and Setting in the roller-drafting of staple-fiber slivers. Journal of Textile Institute, 65, 325-327. [6] Su, C.I., Lo, K.J and Lee, J.Y. (1998). Drafting Force of Fine-Denier Polyester Fibers. Textile Research Journal, 68(8), 559-563. [7] Su, C.I. and Lo, K.J. (2000). Optimum Drafting Conditions of Fine- Denier Polyester Spun Yarn. Textile Research Journal

Open access

Jerzy Jabłecki, Leszek Kaczmarzyk, Adam Domanasiewicz and Maciej Paruzel

Filling of Tissue Defects in the Hand With A Pediculed Osteocutaneous Groin Flap

The aim of the study was to evaluate the efficacy of pedicled osteocutaneous groin flaps in treatment of tissue defects of the hand.

Material and methods. Twelve pedicled osteocutaneous groin flaps were used to fill bone defects of the hand in the same amount of patients (10 males and 2 females) aged 20-53 years (mean 33.4 years, SD 12 years). The defects affected metacarpal bones and wrist in 2 cases, metacarpus alone in 3 cases, fingers - in 4 (total amputations of 3 or 4 fingers), and thumb in 3 (total amputations). The osseous fragment measured from 6-18 ccm (mean 12.4 ccm). The osteosynthesis was performed using K-wires (10 patients) or AO headless cortical screw (2 patients). The flaps were detached gradually starting from postoperative day 18 with the final detachment performed on p.o. day 24-33 (mean 27.2 days, SD 6 days). Once after flap detachment the patients maintained the limb immobilized in a plaster cast for 5 weeks.

Beside local abscess which was successfully treated with compresses, healing of the surgical site was uncomplicated. The bony union was assessed radiological and occurred after 9-13 weeks (mean 11.1 weeks, SD 5 weeks). Due to delayed bone union, one patient required bone slivers grafting which finally lead to unification. All the patients needed secondary plastic surgery of subcutaneous tissue of the flap; however, only 9 of them consented to it. In three patients we substituted the sensibility with a nerve graft according to Holevich.

Results. The described operation did not improve function in patients with wrist-level and metacarpal osseous defects but improved its esthetical aspect; in the other patients the hand function was significantly restored.

Conclusions. In patients disqualified for other methods of reconstructions of the thumb, fingers and bone defects of the hand a satisfactory result may be achieved by using pedicled osteocutaneous flaps from the iliac crest. This method proved to be highly effective.

Open access

Łukasz Bohdal

particle hydrodynamics: theory and application to non-spherical stars, Monthly Notices of the Royal Astronomical Society , 181, 375-389. 7. Golovashchenko S.F. (2006), A study on trimming of aluminum autobody sheet and development of a new robust process eliminating burrs and slivers, International Journal of Mechanical Sciences , 48, 1384-1400. 8. Golovashchenko S.F. (2007), Analysis of Trimming of Aluminum Closure Panels, JMEPEG , 16, 213-219. 9. Heisel U., Zaloga W., Krivoruchko D., Storchak M., Goloborodko L. (2013), Modelling of orthogonal

Open access

Łukasz Bohdal, Katarzyna Tandecka and Paweł Kałduński

, 181, 375-389. 9. Godec Z. (1977), Influence of Slitting on Core Losses and Magnetization Curve of Grain Oriented Electrical Steels, IEEE Trans. Magn ., 13 (4), 1053-1057. 10. Golovashchenko S.F. (2006), A study on trimming of aluminum autobody sheet and development of a new robust process eliminating burrs and slivers, International Journal of Mechanical Sciences , 48, 1384-1400. 11. Gontarz S., Radkowski S . (2012), Impact of various factors on relationships between stress and eigen magnetic field in a steel specimen. Magnetics, IEEE

Open access

Samiha M. Gawish, Amina A. Gamal El Din, Hanaa H. Ahmed, Abdel Razik H. Farrag and Amira Abou-El Kheir

References 1. Tsala DE, Amadou D, Habtemariam S. Natural wound healing and bioactive natural products. Phytopharmacology. 2013; 4(3): 532-60. 2. Vanscheidt W, Lazareth I, Routkovsky-Norval C. Safety evaluation of a new ionic sliver dressing in the management of chronic ulcers. Wounds. 2003; 15: 371-78. 3. Leaper Dl. Silver dressings: their role in wound management. Int Wound J. 2006; 3(4):282-94. 4. Templeton S. Management of chronic wounds: the role of silvercontaining dressings. Primary

Open access

Assad Farooq, Muhammad Ilyas Sarwar, Muhammad Azeem Ashraf, Danish Iqbal, Azmat Hussain and Samander Malik

. Cherif. (2008). Use of artificial neural networks for determining the leveling action point at the auto-leveling draw frame.Textile Research Journal, 78, 502-509. [24] Huang, C.C., & K.T. Chang. (2001). Fuzzy self-organizing and neural network control of sliver linear density in a drawing frame. Textile Research Journal, 71, 987-992. [25] Cheng, L., & D.L., Adams. (1995). Yarn strength prediction using neural networks Part I: Fibre properties and yarn strength relationship. Textile Research Journal, 65, 495-500. [26] Sette, S., L., Boullart, L