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The use and importance of mélange yarn in apparel sector is increasing day by day. With the gradual increase in market share, achieving the desired quality level of mélange yarn remains a challenge for yarn manufacturing industry. The purpose of this paper is to investigate the effect of raw material (dyed fiber percentage in the mixing), important spinning process variable (yarn twist multiplier) and productivity (spindle rpm of ring frame) on properties of cotton mélange spun yarn.

Box and Behnken Design of experiment has been used to investigate the important yarn quality parameters like evenness, imperfection, hairiness, breaking strength and breaking elongation of blow room blended cotton mélange yarn. The quadratic regression model is used to derive the statistical inferences about sensitivity of the yarn quality parameters to the different process variables. The response surfaces are constructed for depicting the geometric representation of yarn quality parameters plotted as a function of process variables.

The study shows that shade depth and spindle speed have significant effects on the mélange yarn unevenness and imperfections. Mélange yarn strength and hairiness are significantly affected by shade depth and yarn twist multiplier (TM). Yarn elongation at break is only influenced by the spindle speed. A darker shade is responsible for higher yarn unevenness, imperfection, hairiness and lower yarn strength. A higher spindle speed is also liable for deterioration of yarn quality.

Many spinning industries are planning to convert their existing spindles from normal gray yarn production to mélange yarn manufacturing. The outcome of this study will lead to achieve better mélange yarn quality and productivity by the industry.

Research on mélange yarn is itself scant. This study is exclusively conducted to analyze the individual and interactive effect of various process parameters on the mélange yarn quality.

LOCATED AT the company's Tulsa, Oklahoma refinery, the multi‐million dollar plant of the Sunray DX Oil Company has one of the world's most modern and complete lubricating oil blending, packaging and shipping plants.

This study aims to investigate the effect of process parameters of blow room machines on openness degree and quality of cotton tufts in a blow room.

For this purpose, an experimental Box–Behnken design (BBD) was used, and the process parameters were the angles of the grid bars underneath the opening rollers of CVT3 beaters and the distance between feed roller of the first opening roller of CVT3.

It was found that the cotton tuft openness increased by increasing the angles of grid bars and by decreasing the distance between the feed roller and first opening roller on CVT3 beater. Further, the optimization procedure showed that an optimum value of cotton tuft openness (in laser method) was determined for specific levels of the process parameters.

The originality of this investigation is that it showed the individual effects and interactions of the most important factors in two tufting machines instead of only one machine. This study is important because it helps cotton yarn spinners to improve the quality of the final yarns by optimizing the levels of tuft openness which in turn improves fiber cleaning.

Grey cotton fibers with a mean fiber length and fineness of 29 mm and 4.2 micronair was pretreated, scoured and dyed. Three ring yarns were spun separately from 100% grey cotton (R.R.Y.), 50% dyed and 50% grey cotton blend (M.R.Y.) and 100% dyed cotton (D.R.Y.). The extent of fiber damage was assessed by measuring the length and the mechanical characteristics of cotton fibers after passing the fibers through the lap machine and the draw frame II. Properties of R.R.Y., M.R.Y. and D.R.Y. samples were examined. In terms of tenacity and elongation at break, grey and dyed cotton fibers, which were selected after being processed by the lap machine and the draw frame II, were very similar. The fiber length by number and weight of grey cotton was longer than that of dyed cotton, while the amount of fiber nep and short fiber content of dyed cotton were more than those of grey cotton.

The three yarn samples were the same in terms of elongation at break. The tenacity of R.R.Y. was the highest but the yarn sample was the lowest in terms of coefficients of mass variation (Cv%), imperfection and hairiness in comparison with the M.R.Y. and D.R.Y. samples.

The purpose of this paper is to study the 100 percent pure cotton and 50:50 cotton and regenerated fibers (tencel, modal, bamboo, viscose) blends. The blends of regenerated fibers with cotton are studied so as to replace 100 percent cotton fabrics with the cotton blends as cotton cannot fulfill the demand of clothing due to the increasing population.

In order to conduct this study, cotton, as natural cellulose fiber, was used. Regenerated fibers include viscose, tencel, modal and bamboo. Five yarn samples of Ne 30/1 of 100 percent cotton and blends (50:50) of cotton with tencel, modal, bamboo and viscose fibers were produced. The blending was done in the Blow-room, and yarn samples were produced by employing the ring spinning technique. Plain woven fabrics samples with Ends (76) and Picks (68) per inch of 120 gsm were prepared. The fabric samples were tested for mechanical (warp and weft tensile and tear strengths) and comfort properties (air permeability, moisture management and thermal resistance).

Cotton:tencel fabric has the excellent mechanical (tensile and tear strength) as well as comfort properties (air permeability, moisture management and thermal resistance). It means that the most suitable blend that cotton can make with the regenerated fibers is the tencel. Therefore, to have more comfortable fabrics, the fabrics which are being made by 100 percent cotton can be replaced with the cotton:tencel.

To the authors’ information, no study has been reported in which all the regenerated fibers blended with cotton were studied. Hence, the aim of this work is to study the mechanical and comfort properties of the regenerated fibers (modal, tencel, viscose and bamboo) blended with cotton. The blends of cotton with regenerated fibers might replace 100 percent cotton in clothing applications as cotton cannot fulfill the increasing demanding of clothing.

The main objectives of this research work were to investigate the effect of production speed on intermingled yarn properties and melange fabric properties with special reference to melange appearance.

Polyester/nylon intermingled yarns were produced using an SSM DP3-C air-intermingling machine using commercial process parameters and Heberlein P212 nozzle. Melange fabric samples were knitted from polyester/nylon intermingled yarns while maintaining the same parameters to avoid knitting variations. The fabric samples were dyed using a sample dyeing machine while maintaining dye recipe and dyeing parameters constant to avoid dyeing variations.

The production speed has significant effect on intermingled yarn and melange fabric properties. When the production speed is increased, mingle points, mingle stability, linear density, strength and the elongation of the intermingled yarns decreases. When the production speed is increased, fabric weight decreases and the melange effect varies from dot-like appearance to line-like appearance.

Only the effect of production speed on intermingled yarn and melange fabric properties is discussed in this paper. Appearance evaluating systems developed in this research are limited to melange fabrics produced using air-intermingled yarns with two colour components.

Results indicate that the intermingled yarns for the application of melange fabrics should be developed with optimum intermingling speeds, and it should not be changed during the production since production speed has significant effect on yarn and fabric parameters. Therefore, melange appearance and fabric weight may vary between fabric lots with different production speeds even though all the other parameters are kept constant. Further, melange appearance evaluation method developed in this research could be used as a guide in developing melange fabrics.

This research introduced a qualitative and a quantitative method to analyse melange fabric appearance. This melange appearance evaluation method can be used as a guide to achieve specific melange effect in the sample development stage. Further, when a melange sample appearance catalogue is developed for all the variables for a particular fabric type using this evaluation method, customer requested appearance can be achieved in minimum sample trials which save time, capacity, money and customer credibility.

The purpose of this study is to improve the mechanical property and processing performance and reduce the cost of the polylacticacid/polybutyleneadipate-co-terephthalate(PLA/PBAT) composites, the calcium carbonate (CaCO₃) and compatibilizer styrene-maleicanhydride copolymer (SMA-2025) were added to the PLA/PBAT system, and the effect of CaCO₃ and SMA-2025 on the morphology, structure, mechanical property, thermal property, thermalstability and shape memory property of the CaCO₃/PLA/PBAT composites were studied and discussed.

The CaCO₃/PLA/PBAT shape memory composites were prepared via melt-blending and hot-pressing methods, and the effect of CaCO₃ and SMA-2025 on the property of the composites was investigated via scanning electron microscope, universal testing instrument, Fourier transform infrared spectroscopy, differential scanning calorimetry, thermogravimetric analysis and DMA, respectively.

The interface property, mechanical property, thermal stability, shape memory recovery ratios and recovery stresses, and processing performance of the CaCO₃/PLA/PBAT shape memory composites were significantly improved by adding of CaCO₃ and SMA-2025. Moreover, the CaCO₃/PLA/PBAT composites have good blowing film processing performance.

This study will provide a reference for the research, processing and application of the high-performance CaCO₃/PLA/PBAT shape memory composites.

THE TERM “SOLUBLE OIL,” whilst well established in engineering practice is a misnomer, the oils are not soluble but emsulifiable and are blends of mineral oil with a suitable emulsifier. To illustrate this it might even be said that a very crude soluble oil is formed when soap is rubbed into oily hands. Certainly a crude emulsion results when the hands are subsequently rinsed. Modern soluble cutting oils are much more complex than this, the emulsifier usually consisting of a blend of petroleum sulphonates with soaps of fatty acids. Since this emulsifier may not readily form a homogeneous blend with the mineral oil some “coupling” or “linking” agent is often necessary to prevent separation and to ensure rapid and even dispersion of the oil when it is added to water.

The next month or two behind us and this decade will have passed, to merge in the drab background of the post‐war years, part of the pattern of frustration, failure and fear. The ‘swinging sixties’ some called it, but to an older and perhaps slightly jaundiced eye, the only swinging seemed to be from one crisis to another, like the monkey swinging from bough to bough in his home among the trees; the ‘swingers’ among men also have their heads in the clouds! In the seemingly endless struggle against inflation since the end of the War, it would be futile to fail to see that the country is in retreat all the time. One can almost hear that shaft of MacLeodian wit christening the approaching decade as the ‘sinking seventies’, but it may not be as bad as all that, and certainly not if the innate good sense and political soundness of the British gives them insight into their perilous plight.

The complex cellular structure and chemical nature of fruit and vegetable tissues retard evaporation so that under no conditions of temperature and humidity does the rate of evaporation from them equal that from a free water surface. When conditions are such that surface evaporation from the tissues exceeds the rate of moisture diffusion to the surface, the surface becomes dry and hard and seals in the moisture. This condition, known as case‐hardening, is overcome by reducing the temperature of the air or by increasing the humidity. The maximum rate of drying, then, is attained by using the highest temperature which will not injure the product, the humidity being sufficient to prevent case‐hardening. In general practice the temperature of the air entering the drying chamber should not exceed 160° to 170° F. The humidity at the air‐outlet end of the drier should not greatly exceed 65 per cent. In driers employing recirculation the conditions of temperature and humidity may be largely controlled by varying the recirculation. The velocities of air flow which produce the most efficient results in the drying chamber depend upon several conditions. In general the rate of drying increases with the velocity of air movement. Low air velocities tend to bring about slow and uneven drying. Exceedingly high velocities may not be used profitably because a point is app ched at which the materials will be blown from the trays or at which the increased speed of drying will not offset the cost of operating a larger fan. Velocities of 600 to 800 feet per minute through the drying chamber are satisfactory in tunnel driers; lower velocities are permissible in compartment driers. The most practical means of removing moisture from the air, and at the same time conserving heat, is through the steady discharge of a portion of the air leaving the drying chamber. The rest dries efficiently when mixed with fresh air from the outside and reheated. All forced‐draught driers, therefore, should be provided with recirculation ducts connecting the air‐outlet end of the drying chamber with the heaters and with dampers controlling the air discharged, recirculated, and drawn from the outside. Dehydrated fruits and vegetables should have a uniform moisture content low enough to inhibit undesirable microbic and chemical changes within the food, and they should be free from any part of the life cycle of moths or other insects. The moisture content of dehydrated foods directly controls deterioration within the food, and the protection afforded by sulphuring or blanching will not prevent insufficiently dried products from soon becoming unfit for use. Dehydrated products having a low moisture content are not readily attacked by insects. In the long run the additional protection afforded by a low moisture content will more than make up to the producer the loss resulting from the longer drying time and greater weight shrinkage involved. To assure best keeping qualities the moisture content of fruits containing much sugar should not exceed 15 to 20 per cent., while that of other fruits and vegetables should not exceed 5 to 10 per cent., the preference in both cases being for the lower percentage. The texture, or feel, of products is a guide in determining when the proper stage of dryness has been reached. At a given moisture content products usually feel softer when hot than after they have been cooled, and often they feel softer after standing until the moisture has become evenly distributed throughout the pieces than when first cooled. A rough test for moisture in dried fruits is to take up a double handful, squeeze it tight into a ball, and release the pressure. If the fruit seems soft, mushy, or wet, and sticks together when the pressure is released, the moisture content is probably 25 per cent. or more. If the fruit is springy, and, when the pressure is released, separates in a few seconds to form pieces of approximately the original size and shape, the moisture content is usually about 20 to 25 per cent. If the fruit feels hard or horny and does not press together, falling apart promptly when the pressure is released, the moisture content is probably below 20 per cent. At the proper stage of dryness vegetables look thoroughly dry and are often hard or crisp. The Association of Official Agricultural Chemists has published a method for the determination of moisture in dried fruits. In using methods of this type, care must be taken to select a composite sample from different parts of the lot, so that it will be representative of the lot as a whole, and directions for preparing the sample must be carefully followed in order to obtain dependable results. Products are never uniformly dry when removed from the drier. Large pieces and pieces not as directly exposed to the currents of heated air as most of the material contain more moisture than the rest. Products should be stored in large bins until the moisture becomes evenly distributed. This period of curing will usually take several weeks. An alternative method is to place the dried product in large friction‐top cans for curing, thus insuring complete protection from contamination and insect infestation. Leafy vegetables, like spinach, must remain in the drier until the moisture content of the stems is very low. At this point the product is bulky and the leaves are brittle. For economy in packing and handling it is desirable to reduce the bulk by compression. For this purpose the leaves are exposed to currents of cool damp air until they have reabsorbed just enough moisture to make them slightly flexible. For convenience in handling and to facilitate the application of heat or fumigation, products should be packed in the room where they were cured and stored. Such a room should be strictly clean, dry, cool and well ventilated. The doors should fit tightly, and the windows should be covered with fine‐mesh screen to exclude dust and insects. An abundance of light assists in detecting the presence of insects and in keeping the room clean. The types of containers chosen for packing will depend largely upon the severity of the storage conditions, with particular reference to the humidity and to chances of insect infestation. An ideal container would be one which, while moderate in cost, would keep the product from absorbing moisture when exposed to the most severe conditions of storage and shipment, and would be impervious to insects. Sealed tin cans and glass jars give absolute protection against moisture absorption and insect infestation. Friction‐top cans are nearly as good. Tin containers, necessary for export shipments of dehydrated foods, are more expensive than paper containers. Wooden boxes are generally used for bulk goods. Liners of heavy paper or cardboard, and sometimes additional liners of waxed paper, are used. The use of moisture‐proof cellophane packages is increasing. All types of paper containers with which experiments have been made allow the absorption of moisture when the products are stored in damp places. Also paper containers do not give perfect protection against all insects, some of which can bore holes in paper, while the larval forms of others are so small that they can crawl through the slightest imperfections at the joints where the cartons are sealed. Most products, however, keep satisfactorily in double or triple moisture‐proof cellophane or waxed‐paper bags packed in waxed, moisture‐proof cartons, provided the initial moisture content is low and no live insects in any form enter the package. Packing in insect‐proof and moisture‐proof packages cannot be too greatly stressed.