The Experts below are selected from a list of 312 Experts worldwide ranked by ideXlab platform
Majid Safar Johari - One of the best experts on this subject based on the ideXlab platform.
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Effect of Using the New Solo-Siro Spun Process on Structural and Mechanical Properties of Yarns
Fibres & Textiles in Eastern Europe, 2013Co-Authors: Parham Soltani, Majid Safar JohariAbstract:Mechanical and physical properties of spun yarns are very important for post-spinning operations as well as for determining some final fabric characteristics. These properties greatly depend on the yarn structure characterised by the geometrical arrangement of fi bres in the yarn body. The geometry of the spinning triangle plays a significant role in determining the spun yarn structure. Solo-Siro is a new spinning system which proposes fundamental modifications to the Solo spinning process with the aim of altering the geom etry of the spinning triangle and hence the yarn structure. By comparing Solo-Siro and Solo spun yarns, the present research focuses on identifying those structural differences which can be used to explain the properties of these novel yarns. Results show that Solo-Siro spun yarns enjoy superior physical and mechanical properties in comparison with Solo spun yarns. This can be attributed to the higher mean fibre position, higher migration factor, greater proportion of fibres which are broken during yarn failure and lower hairiness in Solo-Siro spun yarns.
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a study on Siro solo compact and conventional ring spun yarns part ii yarn strength with relation to physical and structural properties of yarns
Journal of The Textile Institute, 2012Co-Authors: Parham Soltani, Majid Safar JohariAbstract:The strength of Siro-, solo-, compact-, and conventional ring-spun yarns has been examined with reference to yarn migration parameters, spinning-in-coefficient, number of broken fibers, and yarn hairiness. The measured results are presented in the forms of diagrams and tables. Results reveal that at various levels of gage length and strain rate, Siro-spun yarns exhibit the highest tenacity, followed by compact-spun yarns, solo-spun yarns, and conventional ring-spun yarns. Analysis of the results demonstrate that the higher tenacity values of Siro-spun yarns can be attributed to the higher mean fiber position, higher migration factor, greater proportion of broken fibers, and lower hairiness. It is also found that the strength of yarns to a considerable extent is governed by yarn structure, gage length, and strain rate.
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a study on Siro solo compact and conventional ring spun yarns part i structural and migratory properties of the yarns
Journal of The Textile Institute, 2012Co-Authors: Parham Soltani, Majid Safar JohariAbstract:Properties of spun yarns are mainly affected by fiber properties and yarn structure. Yarn structure is principally influenced by the spinning system. In fact, each spinning system tends to produce a distinctive yarn structure. Recent refinements in spinning technologies have yielded significant improvement in yarn structure. Siro, solo and compact spinning are the new spinning systems to have made a breakthrough until recently. Of the various structural parameters for staple yarns, fiber migration has a crucial influence on the yarn mechanical properties. Thus, the need for precise and concise information about fiber migration becomes important for better understanding of yarn structure and hence yarn mechanical behavior. The work presented here aims to analyze fiber migration in Siro-, solo-, compact-, and conventional ring-spun yarns by varying the twist factor. The results demonstrate that the Siro-spun yarns exhibit the highest fiber migration parameters, followed by compact-spun yarns, solo-spun yarn...
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comparison of the properties of ring solo and Siro core spun yarns
Journal of The Textile Institute, 2011Co-Authors: Armin Pourahmad, Majid Safar JohariAbstract:In this research, core‐spun yarns with an acrylic sheath fiber and a nylon flat core have been produced on the Ring, Siro, and Solo spinning systems and the effects of some factors were investigated. The studied factors consist of filament pre‐tension (i.e. 1, 7/5, 10, 15, 50, and 100 g), spinning system (Ring, Siro, and Solo), and feed position of the core filament in the strands of sheath fibers (six types of feed positions). Also, their physical and mechanical properties, including strength, elongation percentage, abrasion resistance, percentage of coefficient of variation (CV%), and hairiness, were all investigated. Finally, in each stage, the best case was determined. The results show that the quality of the core‐spun yarns produced by the Siro spinning system is better than that of the Ring and Solo core‐spun yarns.
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Comparison of the properties of Ring, Solo, and Siro core‐spun yarns
Journal of the Textile Institute, 2011Co-Authors: Armin Pourahmad, Majid Safar JohariAbstract:In this research, core‐spun yarns with an acrylic sheath fiber and a nylon flat core have been produced on the Ring, Siro, and Solo spinning systems and the effects of some factors were investigated. The studied factors consist of filament pre‐tension (i.e. 1, 7/5, 10, 15, 50, and 100 g), spinning system (Ring, Siro, and Solo), and feed position of the core filament in the strands of sheath fibers (six types of feed positions). Also, their physical and mechanical properties, including strength, elongation percentage, abrasion resistance, percentage of coefficient of variation (CV%), and hairiness, were all investigated. Finally, in each stage, the best case was determined. The results show that the quality of the core‐spun yarns produced by the Siro spinning system is better than that of the Ring and Solo core‐spun yarns.
Jan Hubert - One of the best experts on this subject based on the ideXlab platform.
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Detection and localization of Solitalea-like and Cardinium bacteria in three Acarus Siro populations (Astigmata: Acaridae)
Experimental and Applied Acarology, 2016Co-Authors: Jan Hubert, M. Alejandra Perotti, Jan Kopecky, Marta Nesvorna, Tomas ErbanAbstract:Bacteria associated with mites influence their fitness, nutrition and reproduction. Previously, we found Solitalea -like ( Sphingobacteriales ) and Candidatus Cardinium ( Cytophagales ) bacteria in the stored product mite Acarus Siro L. by cloning and using pyrosequencing. In this study, taxon-specific primers targeting 16S rRNA gene were used to detect and quantify the bacteria in mites and eggs of three A. Siro populations. The specific probes for fluorescent in situ hybridization (FISH) were used to localize Solitalea -like and Cardinium bacteria in mite bodies. The population growth as an indirect estimator of fitness was used to describe the mite-bacteria interactions on (1) control diet; (2) rifampicin supplemented diet; (3) tetracycline supplemented diet; (4) rifampicin pretreated mites; (5) tetracycline pretreated mites. Solitalea -like 16S rRNA gene sequences from A. Siro formed a separate cluster together with sequences from Tyrophagus putrescentiae . qPCR analysis indicated that number of Solitalea -like bacteria 16S rRNA gene copies was ca. 100× higher than that of Cardinium and the numbers differed between populations. FISH analysis localized Solitalea -like bacteria in the parenchymal tissues, mesodeum and food bolus of larvae, nymphs and adults. Solitalea -like, but not Cardinium bacteria were detected by taxon-specific primers in mites and eggs of all three investigated populations. None of the antibiotic treatments eliminated Solitalea -like bacteria in the A. Siro populations tested. Rifampicin pretreatment significantly decreased the population growth. The numbers of Solitalea -like bacteria did not correlate with the population growth as a fitness indicator. This study demonstrated that A. Siro can host Solitalea -like bacteria either alone or together with Cardinium . We suggest that Solitalea -like bacteria are shared by vertical transfer in A. Siro populations.
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the effect of stored barley cultivars temperature and humidity on population increase of acarus Siro lepidoglyphus destructor and tyrophagus putrescentiae
Experimental and Applied Acarology, 2013Co-Authors: Jan Hubert, Stano Pekár, Radek Aulický, Marta Nesvorna, Václav StejskalAbstract:The rate of population increase of three mite species, Acarus Siro (L.), Lepidoglyphus destructor (Schrank) and Tyrophagus putrescentiae (Schrank), was studied on various types of barley and at various combinations of temperature and humidity. The mites were added into the chambers and incubated for 21 days on seven different kinds of barley coming from four sites, including six cultivars and a mixture. The population increase of all species was higher on the mixture than on any other cultivar, except for Sebastian and Calgary. The increase of mites was studied at constant temperatures ranging from 5 to 35 °C and relative humidity (RH) ranging from 50 to 90 %. Positive rate of increase was found above 70 % RH for all species. The optimal humidity was at 85 % RH for A. Siro and L. destructor and at 90 % RH for T. putrescentiae. As concerns the temperature, positive rate of increase was found at temperatures higher than 10, 15 and 20 °C for A. Siro, L. destructor and T. putrescentiae, respectively. The temperature optima were at 23, 25, and 30 °C for A. Siro, L. destructor and T. putrescentiae, respectively. Model estimated on laboratory data was then fitted to temperature and humidity records from August to November in the Czech grain store. Estimated population rate of increase was rarely positive: for A. Siro it was for 24 %, for L. destructor for only 1 % and for T. putrescentiae for only 7 % days of the study period. It is concluded that in the climatic conditions of the Czech Republic the population increase of three mite pests is negligible during autumn and winter.
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Detection and Identification of Species-Specific Bacteria Associated with Synanthropic Mites
Microbial Ecology, 2012Co-Authors: Jan Hubert, Jan Kopecky, Marta Nesvorna, M. Alejandra Perotti, Henk R. Braig, Markéta Ságová-marečková, Lilia Macovei, Ludek ZurekAbstract:Internal bacterial communities of synanthropic mites Acarus Siro , Dermatophagoides farinae , Lepidoglyphus destructor , and Tyrophagus putrescentiae (Acari: Astigmata) were analyzed by culturing and culture-independent approaches from specimens obtained from laboratory colonies. Homogenates of surface-sterilized mites were used for cultivation on non-selective agar and DNA extraction. Isolated bacteria were identified by sequencing of the 16S rRNA gene. PCR amplified 16S rRNA genes were analyzed by terminal restriction fragment length polymorphism analysis (T-RFLP) and cloning sequencing. Fluorescence in situ hybridization using universal bacterial probes was used for direct bacterial localization. T-RFLP analysis of 16S rRNA gene revealed distinct species-specific bacterial communities. The results were further confirmed by cloning and sequencing (284 clones). L . destructor and D . farinae showed more diverse communities then A . Siro and T . putrescentiae . In the cultivated part of the community, the mean CFUs from four mite species ranged from 5.2 × 10^2 to 1.4 × 10^3 per mite. D . farinae had significantly higher CFUs than the other species. Bacteria were located in the digestive and reproductive tract, parenchymatical tissue, and in bacteriocytes. Among the clones, Bartonella -like bacteria occurring in A . Siro and T . putresecentiae represented a distinct group related to Bartonellaceae and to Bartonella -like symbionts of ants. The clones of high similarity to Xenorhabdus cabanillasii were found in L . destructor and D . farinae , and one clone related to Photorhabdus temperata in A . Siro . Members of Sphingobacteriales cloned from D . farinae and A . Siro clustered with the sequences of “ Candidatus Cardinium hertigii” and as a separate novel cluster.
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Chitin in the Peritrophic Membrane of Acarus Siro (Acari: Acaridae) as a Target for Novel Acaricides
Journal of economic entomology, 2008Co-Authors: Jan Šobotník, Zuzana Munzbergova, Iva Kudlikova-krizkova, Marie Vancová, Jan HubertAbstract:The peritrophic membrane in Acarus Siro L. (Acari: Acaridae) is produced by distinct cells located in the ventriculus. In this study, the chitin inside the peritrophic membrane was detected using wheat germ-lectin conjugated with colloidal gold (10 nm). The chitin fibrils of the peritrophic membrane were a target for chitin effectors, including 1) chitinase, which hydrolyzes chitin fibers inside the peritrophic membrane; 2) calcofluor, which binds to chitin and destroys the peritrophic membrane mesh structure; and 3) diflubenzuron, which inhibits chitin synthesis. In addition, soybean trypsin protease inhibitor (STI) and cocktails of chitinase/calcofluor, diflubenzuron/calcofluor and chitinase/STI were tested. These compounds were supplemented in diets and an increase of population initiated from 50 individuals was observed after 21 d of cultivation. Final A. Siro densities on experimental and control diets were compared. The chitin in the peritrophic membrane was determined to be a suitable target for novel acaricidal compounds for suppressing the population growth of A. Siro. The most effective compounds were calcofluor and diflubenzuron, whereas the suppressive effects of chitinase and STI were low. The failure of chitinase could be due to its degradation by endogenous proteases. The combination of chitinase and STI suppressed A. Siro population growth more effectively than when they were tested in oral admission separately. The combinations of calcofluor/chitinase or calcofluor/difluorbenzuron showed no additive effects on final A. Siro density. The presence of chitin in peritrophic membrane provides a target for novel acaricidal compounds, which disrupt peritrophic membrane structure. The suitability of chitin effectors and their practical application in the management of stored product mites is discussed.
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assessing biological control of acarus Siro by cheyletus malaccensis under laboratory conditions effect of temperatures and prey density
Journal of Stored Products Research, 2008Co-Authors: Stanislav Pekar, Jan HubertAbstract:Abstract In stored grain, the predatory mite Cheyletus spp. may be used to control the pest mite Acarus Siro . The efficiency of control depends on many factors, particularly ambient temperature. In this study we investigated the effects of temperature and initial prey density on the prey–predator system under laboratory conditions. Ratio–response models were fitted to estimate the efficiency of control for three temperatures. At 15 °C a 90% reduction of A. Siro was achieved by releasing nine Cheyletus malaccensis individuals into a population of 100 A. Siro individuals in 1 kg of grain. At 20 °C, 90% reduction required seven C. malaccensis individuals and at 25 °C, it required three C. malaccensis individuals. Without the predator the intrinsic rates of increase of A. Siro populations increased with temperature and were highest for an initial density of 100 individuals, revealing some form of positive interaction among A. Siro individuals during food processing. The intrinsic rates of increase of C. malaccensis populations also increased with temperature and decreased with increasing density of the predator, presumably as a result of interference competition among predators. At 15 °C the rate of increase for A. Siro was higher than that for C. malaccensis, while at higher temperatures it was the other way around. Lower developmental thresholds were 10 °C for A. Siro and 13.6 °C for C. malaccensis . In order to find when an artificial release of C. malaccensis is most efficient we simulated a population increase of A. Siro using temperature records from one grain store. In Central Europe this type of biological control can be efficient only when the predator is released at the beginning of storage, i.e. in September and October.
Parham Soltani - One of the best experts on this subject based on the ideXlab platform.
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Effect of Using the New Solo-Siro Spun Process on Structural and Mechanical Properties of Yarns
Fibres & Textiles in Eastern Europe, 2013Co-Authors: Parham Soltani, Majid Safar JohariAbstract:Mechanical and physical properties of spun yarns are very important for post-spinning operations as well as for determining some final fabric characteristics. These properties greatly depend on the yarn structure characterised by the geometrical arrangement of fi bres in the yarn body. The geometry of the spinning triangle plays a significant role in determining the spun yarn structure. Solo-Siro is a new spinning system which proposes fundamental modifications to the Solo spinning process with the aim of altering the geom etry of the spinning triangle and hence the yarn structure. By comparing Solo-Siro and Solo spun yarns, the present research focuses on identifying those structural differences which can be used to explain the properties of these novel yarns. Results show that Solo-Siro spun yarns enjoy superior physical and mechanical properties in comparison with Solo spun yarns. This can be attributed to the higher mean fibre position, higher migration factor, greater proportion of fibres which are broken during yarn failure and lower hairiness in Solo-Siro spun yarns.
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a study on Siro solo compact and conventional ring spun yarns part ii yarn strength with relation to physical and structural properties of yarns
Journal of The Textile Institute, 2012Co-Authors: Parham Soltani, Majid Safar JohariAbstract:The strength of Siro-, solo-, compact-, and conventional ring-spun yarns has been examined with reference to yarn migration parameters, spinning-in-coefficient, number of broken fibers, and yarn hairiness. The measured results are presented in the forms of diagrams and tables. Results reveal that at various levels of gage length and strain rate, Siro-spun yarns exhibit the highest tenacity, followed by compact-spun yarns, solo-spun yarns, and conventional ring-spun yarns. Analysis of the results demonstrate that the higher tenacity values of Siro-spun yarns can be attributed to the higher mean fiber position, higher migration factor, greater proportion of broken fibers, and lower hairiness. It is also found that the strength of yarns to a considerable extent is governed by yarn structure, gage length, and strain rate.
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a study on Siro solo compact and conventional ring spun yarns part i structural and migratory properties of the yarns
Journal of The Textile Institute, 2012Co-Authors: Parham Soltani, Majid Safar JohariAbstract:Properties of spun yarns are mainly affected by fiber properties and yarn structure. Yarn structure is principally influenced by the spinning system. In fact, each spinning system tends to produce a distinctive yarn structure. Recent refinements in spinning technologies have yielded significant improvement in yarn structure. Siro, solo and compact spinning are the new spinning systems to have made a breakthrough until recently. Of the various structural parameters for staple yarns, fiber migration has a crucial influence on the yarn mechanical properties. Thus, the need for precise and concise information about fiber migration becomes important for better understanding of yarn structure and hence yarn mechanical behavior. The work presented here aims to analyze fiber migration in Siro-, solo-, compact-, and conventional ring-spun yarns by varying the twist factor. The results demonstrate that the Siro-spun yarns exhibit the highest fiber migration parameters, followed by compact-spun yarns, solo-spun yarn...
K. Ülger - One of the best experts on this subject based on the ideXlab platform.
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Properties of Plain Knits from Siro-Spun Viscose/Spandex Yarns
Fibres & Textiles in Eastern Europe, 2010Co-Authors: Y. Beceren, Cevza Candan, S. Duru Cimilli, K. ÜlgerAbstract:This paper focuses on the dimensional and selected physical properties of a series of plain jersey fabrics made from viscose Siro-spun and carded ring yarns of 2/10 tex and 20 tex, respectively. Elastane yarn was incorporated into the fabric using the plaiting technique. In general, for both greige and dyed knitted fabrics, the stitch density decreased, whereas the weight increased as the stitch length increased. Moreover, for greige and dyed dry-relaxed fabrics from Siro yarn, the twist had an influence on fabric properties, the effect being rela tively more prominent for slack samples. Moreover, both slack and tight dry relaxed dyed samples from high twist Siro yarns featured lower resistance to abrasion. As far, as dyed and laundered samples from Siro yarns are concerned, the results revealed that irrespective of the loop length, the samples from average twist Siro yarns tended to give a higher stitch density and weight values. When abrasion resistance values of samples from both average and high twist Siro yarns were studied, it could be suggested that in addition to yarn properties, the effect of fabric properties on the abrasion behaviour of the samples became more prominent after laundering. As far as the abrasion resistance and pilling properties of the samples are concerned, the fabrics from Siro-spun yarns tended to perform better. Finally, the pilling test method employed affected not only the size and shape of the pill entanglements on the surface of the samples but also the degree of fibre damage within the fuzz entanglements.
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properties of plain knits from Siro spun viscose spandex yarns
Fibres & Textiles in Eastern Europe, 2010Co-Authors: Y. Beceren, Cevza Candan, Duru S Cimilli, K. ÜlgerAbstract:This paper focuses on the dimensional and selected physical properties of a series of plain jersey fabrics made from viscose Siro-spun and carded ring yarns of 2/10 tex and 20 tex, respectively. Elastane yarn was incorporated into the fabric using the plaiting technique. In general, for both greige and dyed knitted fabrics, the stitch density decreased, whereas the weight increased as the stitch length increased. Moreover, for greige and dyed dry-relaxed fabrics from Siro yarn, the twist had an influence on fabric properties, the effect being rela tively more prominent for slack samples. Moreover, both slack and tight dry relaxed dyed samples from high twist Siro yarns featured lower resistance to abrasion. As far, as dyed and laundered samples from Siro yarns are concerned, the results revealed that irrespective of the loop length, the samples from average twist Siro yarns tended to give a higher stitch density and weight values. When abrasion resistance values of samples from both average and high twist Siro yarns were studied, it could be suggested that in addition to yarn properties, the effect of fabric properties on the abrasion behaviour of the samples became more prominent after laundering. As far as the abrasion resistance and pilling properties of the samples are concerned, the fabrics from Siro-spun yarns tended to perform better. Finally, the pilling test method employed affected not only the size and shape of the pill entanglements on the surface of the samples but also the degree of fibre damage within the fuzz entanglements.
Xungai Wang - One of the best experts on this subject based on the ideXlab platform.
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Siro and solo spinning
Advances in Yarn Spinning Technology, 2010Co-Authors: Peter R. Lamb, Xungai WangAbstract:This chapter describes two modifications made to the conventional ring spinning technology, termed Sirospun™ and Solospun™, which were primarily aimed at significantly reducing the production cost of fabrics. Both were invented at CSiro in Australia, hence the name ‘Siro’ spinning. The properties of Sirospun and Solospun yarns are different from those of conventional ring-spun yarns and this has opened new market opportunities.
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The new solo-Siro spun process for worsted yarns
Journal of the Textile Institute, 2006Co-Authors: Saeed Shaikhzadeh Najar, Z. A. Khan, Xungai WangAbstract:Abstract The aim of this paper was to explore whether the properties of worsted yarns, especially hairiness, can be improved by combining the Solospun and Sirospun processes into a single Solo-Siro spun process. Wool fibres of 19 and 21 μm in average diameter were spun into 40 tex yarns at different twist levels, using the conventional ring, Sirospun and Solo-Siro spun systems, respectively. These yarns were then tested for a range of properties, including hairiness, tenacity, elongation and evenness, for comparison purposes. The statistical analysis results indicate that the hairiness (S3 value) of Solo-Siro spun yarns was significantly less than that of both Sirospun and normal ring spun yarns. In addition, the tenacity of the Solo-Siro spun yarns was higher than that of the normal ring spun yarns, while changes in yarn breaking elongation were not statistically significant. For the 21 μm wool, it was found that the evenness of Solo-Siro spun yarns deteriorated slightly in comparison with that of Sirosp...
