bluuebunny/crossref_metadata_2025 huggingface dataset:
Optimal prepositioning of empty freight cars
Authors: Ratcliffe Larry L. , Vinod B. , Sparrow Fredrick T.
Published: March 2007

The optimal utilization and distribution of empty freight cars has plagued the railroad industry in the past and will undoubt edly continue to do so in the future. In this paper we present the methodology for a simulation-optimization model, for the movement of empty freight cars in a hypothetical railroad transportation network. The freight car network is modelled in SLAM and integrated with XMP, a sophisticated and compact linear programming software package, to determine optimal movement and prepositioning of empty cars to the various nodes (terminals) in the network.

The simulation model provides the required data structure for the XMP package to execute the transportation linear program and the stochastic linear program. The model is versatile and with the aid of reliable data, could prove to be a valuable tool for railroad managers and engineers.
Gyrocompassing on a moving land vehicle
Authors: Feng Peide , Hung James C.
Published: March 2007

A scheme is presented of continuous gyrocompassing of an in ertial measurement unit (IMU), aided by an odometer, on a mov ing land vehicle. Kalman filtering is employed to realize the aiding function. Feasibility of the concept is demonstrated by the result.
Simulation nets, a simulation modeling and validation tool
Authors: Törn Aimo A.
Published: March 2007

Simulation nets can serve as a tool for discrete-event simulation. This tool is based on Petri nets with extensions for modeling, validating, and experimenting. Petri nets have been extensively explored since 1962. The resulting publications are easy to understand and are structured in a hierarchical fashion; the descriptions are so exact that they may be regarded as a pro gramming language. This language does not describe how the simulation should be performed but only what the underlying model looks like (i.e., it is a non-procedural description of the simulation program). Thus, it is possible to obtain simulation results in only a fraction of the time needed for tools requiring programming.
Transportation of programs
Authors: de Maine P.A.D. , Leong S.
Published: March 2007

There is a problem with transporting programs so that they will efficiently execute in a new object environment. A review in dicates that the Transportable Programming Language (TPL) method leads to greater execution-time efficiency. However, a hardware implementation of the emulation method can increase the flexibility of the TPL method.
Random process simulation using a continuous system simulation language
Authors: Griffith James M.
Published: March 2007

Computer simulations of physical systems often include effects of random disturbances. A method is derived for including those disturbances in continuous system simulation language (CSSL) computations. This note shows that the effects of white (or colored) noise are easily implemented by using a random number generator of proper variance. The numerical example of an exponentially correlated random variable illustrates the simulation technique.
A pseudorandom number generator
Authors: Clark R.N.
Published: March 2007

A simple deterministic algorithm produces a finite sequence which exhibits three iniportant statistical properties. This algo rithm should prove to be useful in simulating some random processes.
Simulation of urban service operations for locational decisions
Authors: Parkan Celik , Berman Oded
Published: March 2007

Locational issues arise in the provision of urban services; for in stance, finding an optimal home location for a service facility in an urban setting is difficult when the interarrival times of ser vice calls and times are governed by nondeterministic processes. In the steady state, there exists an analytical solution to the prob lem of finding a location minimizing the expected response time.2 This solution is obtained under the assumptions that (1) the service calls are generated by a homogeneous Poisson process; (2) the server always returns to the facility; (3) service requests are handled on a first-in-first-out basis; and (4) the travel speed is constant. Our experiments with a simulation model where the above assumptions have been relaxed indicate that the results are significantly affected by these assumptions and that the steady state may take too long to reach.
Heat exchanger optimization in a crude preheat train
Authors: Ramsay Albert L , Khator Suresh K.
Published: March 2007

Determining the sizes of heat exchangers which minimize the cost of a crude preheat train were investigated. SIMAN was used to simulate the system for different overdesign factors, and it was found out that the operating cost was minimized by maximiz ing the furnace coil outlet temperature.

An overdesign factor of 10% yielded the best results; this is less than the 25% normally used in practice. This suggests that time- dependent simulation can lead to tighter control of overdesign in the design of process equipment under risk and uncertainty conditions. Time-dependent simulations are rarely used in the chemical process industry.
TCL - A FORTRAN-based pointer threaded command language for simulation
Authors: Barkakati Nabajyoti
Published: March 2007

An interactive threaded command language (TCL) was developed for design and simulation applications. The FORTRAN imple mentation of this language emphasizes a basic approach toward developing simulation software rather then the specific command language. TCL incorporates the extensibility and interactive features of threaded interpretive languages such as FORTH and STOIC, but it allows use of all the flexible data structures and numerical capabilities of FORTRAN 77. The approach presented here can easily be adapted to develop other higher level languages tailored to specific applications.

Another interesting feature, within a FORTRAN 77 program, is the handling of various display terminals through an internal data structure and an ASCII text file that contains the terminal's "characteristics".
Versatile Cotton in High Style Finishing
Authors: Heberlein Georg , Weiss Ernst
Published: March 2007

Methods used in actual plant operations for finishing of cotton goods for special fashion effects are surveyed. It is pointed out that by combining two or more treatments an unlimited number of fashion effects can be obtained. Many concrete examples of fabrics produced in such a manner are discussed and illustrated. Cotton lends itself to a greater number of finishing methods than any other fiber. This point is emphasized, and the versatility of cotton is demonstrated by a diversity of high grade finishes on fabrics.
The Application of Resin Finishes to Cotton Garments Using Drycleaning Plant Equipment1
Authors: Graham Robert T. , Loibl Fred , Wiebush Joseph R.
Published: March 2007

Preliminary results are given from a study of the application of a resin finish to cotton garments using drycleaning plant equipment. Cotton fabric swatches of various constructions, including print cloth, denim, sateen, cord, broadctoth. gingham, corduroy, and suiting materials were used.

The objective of the work is to impart wrinkle resistance and desirable permanent creases to cotton garments.

A tentative procedure for the resin treatment has been devised which has proven effective on various weaves and weights of cotton fabrics.

The cost of application of the resin finish to cotton cord suits in a drycleaning plant has been estimated.
Comparative Mercerization of Yarns Made From Pima S-1, Peruvian Pima B-B, and Egyptian Karnak Cottons
Authors: Murphy Alton L. , Goldthwait Charles F.
Published: March 2007

The mercerizing characteristics of yarn made from lots of Pima S-1. Peruvian Pima. and Egyptian Karnak cottons have been compared. The yarns were mercerized in several different ways to compare them under these different conditions; very little difference was found among the cottons. These tests were part of an extensive study of methods for evaluating the mercerizing characterstics of cottons of different varieties or Krowths. which is of interest to both breeder and user of cottons. The comparisons made here are reported because of particular immediate interest by users of these cottons.
An Application of a Sequential Type Analysis , to Field Tests
Authors: Rush H.R.
Published: March 2007

A unique situation is encountered in determining the durability of fabrics under field test situations; i.e., the data can be analyzed at any point in time in the test. This sug gests that the sensitivity of the test can be determined at any point by utilizing the well- known concept of the power of the analysis of variance test. With this information, a decision can be made to stop or continue the test as in the usual sequential procedures. The results of the application of this method to an actual test is presented.
Cotton Cross-Linked at Various Degrees of Fiber Swelling
Authors: Reeves Wilson A. , Perkins Rita M. , Chance Leon H.
Published: March 2007

Wet and dry density measurements were made on a wide variety of wash-and-wear cotton fabrics and some interpretations of these values are given. Methylenated cotton was selected for more extensive fundamental study because of the simplicity of the formaldehyde cross link and the fact that formaldehyde can be reacted with cotton under greatly different conditions. Formaldehyde was used to cross link cotton print cloth at various degrees of fiber swelling by reacting in systems ranging from completely aqueous to anhydrous using hydrochloric acid as catalyst. The amount of water in the system at the time of reaction is related to the extent of fiber swotting. The extent of swelling at the time of cross-linking and the extent of cross-linking influence wet density, which may be considered to be a measure of the water swellability of a fiber. Cross-linking tends to fix or stabilize a fiber in a given state of swelling: the stabilization is more effec tive when the cross-linking is done in nearly anhydrous systems. The state of swelling at the time of cross-linking modifies moisture regain, water of imbibition, dyeabitity, and wet and dry wrinkle recovery. There seems to be an optimum water content in the reaction system at the time of cross-linking for maximum dry and wet wrinkle recovery. As the water content in the reaction system is increased beyond the optimum, the amount of dry wrinkle recovery becomes much less than wet wrinkle recovery. This phenomenon leads to vastly different wash-and-wear ratings of fabric.

A mechanism is presented diagrammatically to explain wet and dry wrinkle recovery. The mechanism is based upon hydrogen-bond cross links, covalent-bond cross links, and the position of the two types of cross links.
Felting Investigations
Authors: Crewther W.G. , Dowling L.M.
Published: March 2007

Observations of changes in crimp of wool fibers during supercontraction in aqueous solutions have led to a means of modifying the crimp of fibers from a single fleece. Felting studies on such modified fibers have shown that straightening of the wool facilitates felting whereas the imposition of tight coils in the fibers retards felting.
Part III: Shearing and Buckling of Various Commercial Fabrics
Authors: Lindberg Joel , Behre Bengt , Dahlberg Bengt
Published: March 2007

Load-deformation curves obtained by the methods for shearing and buckling de scribed in Part I and II are analyzed and discussed. Parameters obtained from these curves are given for 66 commercial fabrics covering an extreme range. Different fabrics show widely different values for the parameters obtained from both shearing and buck ling curves. It is further shown that there exist close relationships between simple de formations like shearing and plane buckling and complex deformations like buckling of corrugated fabric shells. The formability of a fabric is defined as the maximum com pression a fabric can take up before it buckles, given a certain geometric arrangement. The formability parity determines the tailorability and the crease pattern of fabrics. The formability is dependent on fabric direction, and it is shown that the integrated formability should be related to the product of buckling load and shear angle. A the oretical analysis of formability is given, and it is shown that it can be expressed as the product of an anisotropy ratio and the square of the fabric thickness.

It is further shown that the shell buckling load depends on both the plane buckling load and the shear angle, in such a way that increasing shear angle leads to decreasing shell buckling load. It is shown that combination of high formability and low shell buckling load generally is attained by combining relatively high thickness with low bending modulus. It is also shown that wool fabrics generally have this combination of properties. A fabric map is given for all the commercial fabrics. Each fabric has a certain position on the map dependent on bending stiffness (which is closely related to buckling load) and shear angle.

Attention is given to the relation between creasing behavior of fabrics and fabric prop erties. There is a certain relation between crease recovery angle and formability and a good relation between this angle and the noncyclical energy loss in shell buckling. The hypothesis that recovery properties depend mainly on the interaction within the fabric between frictional forces and elastic forces of the fibers is put forward. The energy loss following any fabric deformation depends mainly on friction. The permanent de formation is probably due to the fact that the elastic forces of the fibers cannot overcome the friction. By means of a rheological model it is shown how friction and fiber stiff ness may interact in a fabric. It is shown that the stiffness value should be that ob tained at infinitely slow loading of the fiber.
Studies in Adsorption
Authors: Giles Charles H.
Published: March 2007

Recent quantitative data for adsorption of disperse dyes on cellulose acetates and the relations between adsorption and dye structure are considered.

The dye probably enters the fiber partly in monodisperse and partly in associated form, and penetrates between the fiber chains in regions inaccessible to water. This type of adsorption produces the characteristic linear adsorption isotherms.

Several properties of the dye molecule determine the maximum adsorption of dye.

Size. The smaller the molecule the easier it can penetrate into the fiber structure, hence the higher the maximum adsorption.

Number of hydrogen donor atoms. The more donor atoms there are the higher is the adsorption, in certain cases; the dye forms —OH... and —NH... bonds with the fiber.

Number of hydrogen acceptor atoms. The dye forms —CH...O, —CH...N, and —CH...Cl bonds with the CH8 groups of the acetyl residues in the fiber.' Thus, the —CH...C1 bond between ethyl acetate and chlorobenzene in aqueous ethanol solution has an energy of about —3 kcal./mole and chlorobenzene itself is strongly adsorbed by cellulose triacetate from this solvent.

In some cases adsorption rises with the number of acceptor atoms; in some cases it falls because of opposing electronic effects of other substituent groups.

Steric effects. Functionality. There is a tendency for wide spacing (e.g. 1:4 disub stitution) of bonding atoms to reduce adsorption, probably by promoting dye-dye asso ciation rather than dye-substrate association.

Nylon and polyethylene terephthalate fibers appear to adsorb by a similar mechanism, polyethylene terephthalate showing additional (aromatic nucleus) dye-fiber association.
The Geometry and Properties of Two-Bar Tricot Fabrics of Acetate, Viscose, and Cotton
Authors: Fletcher Hazel M. , Roberts S. Helen
Published: March 2007

Previous investigations of tricot fabrics in relation to physical properties and dimen sional change due to laundering were extended to include another fiber, cotton, and the determination of effect of different amounts of yarn twist on fabrics of the fibers previously studied. Twenty two-bar tricot fabrics of 70/1 cotton yarn with different runner ratios, and 20 each of acetate and viscose yarns of 75 denier with 21, 10, 20, or 30 turns per inch were included in the research. The effect of twist upon other rela tionships was established from observed data of stitch length, stitch density, diameter of yarn, runner ratios, wales and courses per inch, strength, and elongation. Immediate elastic recovery, permanent set, and delayed recovery were evaluated for a wide range of stress-strain levels.
Studies of High Fastness to Light in Coloring Matters in Hydrophilic Substrates
Authors: Giles Charles H. , Baxter George , Rahman Syed M. K.
Published: March 2007

A variety of dyes of high lightfastness, vis., metal-complex and mordanted dyes on protein and cellulosic substrates, basic dye lakes, and reactive dyes, on cellulose, have been examined by fading-rate and CF (characteristic fastness) measurements. Ap parently in all cases the dye is highly aggregated.

Normally with water-soluble dyes lightfastness improves with rise in concentration ; theoretically this should not occur with pigments applied in substance, but in practice it does do so. The cause is shown to be aggregation of particles by capillary attraction before the fluid matrix sets to a solid.

It is shown that, on account of the relation between the association of a dye and its absorption spectrum, fading may tend to cause a reddening of shade of water-soluble dyes, and a blueing of water-insoluble ones.

The heat of illumination can break down dye aggregates and thus cause an apparent rise in depth of color. This effect, which occasionally masks fading in the early stages. is sometimes favored by dry conditions. The accelerated fading produced by rise in atmospheric humidity is due in some cases partly to the absence of this compensating factor ; but it is also probably due to the mass action effect of an increase in concentration of the moisture that enters into the fading reaction.
A Statistical Procedure for Determining End Breakage Rate in Spinning
Authors: Schultz E. Fred , Little Herschel W. , Tallant John D. , Fiori Louis A.
Published: March 2007

Standard deviations of yarn break data, taken by uniform increments of spindle hours, increased linearly with average rate of breakage and were larger than expected for a Poisson distribution. Transforming the numbers of breaks to log10 (1 + number of breaks) stabilized the variance. In a specific case, analysis of data for 720 spindle hours per yarn taken by 12 increments of 60 hours yielded 95% confidence limits describing the average number of breaks per yarn as within 30% of the observed number of breaks.
Adsorption of Calcium and Polyphosphates on Cotton Cellulose and Its Effect on Soil Deposition
Authors: Rutkowski Beverly J. , Martin Albert R.
Published: March 2007

This study was undertaken to define the role of polyphosphate builders in detergent , systems. Radiochemical methods were employed to trace polyphosphate and calcium reactions with cotton at various calcium to polyphosphate ratios. Cotton does not adsorb polyphosphate in the absence of polyvalent metal ions. The amount of calcium and polyphosphate adsorbed by, or deposited on, cotton during a 10-min. wash in hard water is dependent on the calcium-polyphosphate phase present. A heterogeneous (pre cipitate) phase results in considerable deposition of a calcium-polyphosphate salt, while little deposition or adsorption occurs in a homogeneous (solution) phase. Deposition of clay soil onto cotton is not influenced by the presence of insoluble calcium-polyphos phate salts. However, there appears to be a direct relationship between soil deposition and number of unsequestered or unprecipitated calcium ions remaining in the wash solu tion. Tetrasodium pyrophosphate is relatively more efficient in achieving minimum soil deposition than sodium tripolyphosphate.
Response of Cottons to Chemical Treatments
Authors: Rebenfeld L.
Published: March 2007

Single fibers from six cottons were subjected to a resin finishing treatment during which the tension on each fiber was carefully controlled and systematically varied. It was observed that the changes in mechanical properties resulting from the treatment were highly dependent upon the tension exerted on each fiber during the treatment. Treatments at high tensions resulted in greater resilience increases and lower strength losses than corresponding treatments at low tensions.

The six cottons responded differently to the variations in tension during the treat ment, and this differential response was related to fibrillar orientation as estimated by x-ray angle.
The Effect of Relative Humidity on the Crease Recovery of Some Modified Rayon and Cotton Fabrics
Authors: Gill Robert A. , Steele Richard
Published: March 2007

The changes in crease recovery and water absorption of untreated and modified rayon and cotton fabrics have been studied as a function of relative humidity at 25° C. The crease recovery of rayon was found to be very dependent on relative humidity and water content whereas that of cotton was almost independent. The effects of "dry"-state and "wet"-state cross-linking and other special treatments on the crease-recovery-water- content relationships were studied. All of the modified fabrics exhibited a deep minimum in crease recovery, which is attributed to the glass transition of the fibers. The minimum occurs at the water content which lowers the T, of cellulose to 25° C, the temperature of the experiment. This water content is also marked by a minimum in fiber resiliency. The change in the crease-recovery-humidity relationship produced by cross-linking gen erally parallels the change produced in the corresponding fiber resiliency relation, thereby supporting the interdependency of fiber resiliency and fabric crease recovery.

The rate of crease recovery up to 5-min recovery time was determined for all the fabrics at different humidities. Over this time range, the recovery data were linearly related to log time. Although no minimum in crease recovery could be discerned for untreated rayon and cotton fabrics, the glass transition point was marked by a maximum in recovery rate.
The Effect of Noncellulosic Material on the Actinic Degradation of Cotton Fabric
Authors: Gingras B.A. , Cooney J.D. , Bayley C.H.
Published: March 2007

A study has been made of the effects of copper oxinate and nickel oxinate on the actinic degradation of cotton fabric. Both compounds were found to be protective at all concentrations studied, and their behavior is considered to relate to the fact that they are stable metal chelates and not ionic salts, which are known to accelerate the degradation of cotton. Furthermore, both compounds were found to absorb light in the high-energy ultraviolet region. The results are discussed in terms of structure and degree of ultra violet absorption of the compounds.
Accessibility and Lateral Order Distribution of the Cellulose in the Developing Cotton Fiber1
Authors: Nelson Mary L. , Mares T.
Published: March 2007

Cotton fibers from bolls harvested at 5-day intervals beginning at 20 days after flowering and ending at 50 days ( when the bolls had opened on the plant) 'were preserved in three ways for study in the never-dned state. Preservation was accom plished in 70% aqueous ethanol, 50% aqueous dioxane, and by freezing. Measurements of iodine sorption, red-green ("differential") dye uptake, and liquid-phase deuteration rehydrogenation gave different kinds of estimates of accessibility. These data were interpreted as indicating a relatively open structure during the 20- to 30-day period of growth, and a consolidation of the cellulosic component of the cell wall during the subsequent period of wall-thickening (35 to 45 days after flowering). There was only a small change in magnitude of these data upon boll opening. The leveling-off D.P. was nearly constant from the 30th to the 45th day, but showed a slight decrease after boll opening.

Lateral order distribution was assessed by treatment with sodium hydroxide solu tions of increasing concentrations, followed by moisture sorption measurements and x-ray evaluation of extent of lattice transformation. The data indicated perhaps a slight increase in lateral order from 20 to 30 days after flowering, then a leveling-off from 30 to 45 days and a small increase upon boll opening at 50 days.

These data are interpreted as indicating that the high crystallinity of the mature cotton fiber does not suddenly appear when the fiber first dries as the boll opens, but begins to develop concurrently with the deposition of cellulose during the period of wall thickening, and reaches the final high value by crystallization of an additional small fraction of cellulose upon initial drying.
The Longitudinal Rheological Behavior of Non-uniform Fibers
Authors: Collins J.D. , Chaikin M.
Published: March 2007

This paper is concerned with a mathematical analysis of the longitudinal rheological behavior of dimensionally and structurally variable fibers. At first, the general relation ships for the stress-strain behavior of such fibers are derived by ignoring time effects. The uniform and non-uniform fibers are compared for the case when stress and strain follow a power law relationship, and the stress-strain behavior of non-uniform wool fibers is calculated to illustrate the effect with actual fibers. Structural and dimensional non- uniformities are shown to have considerable significance. When both variabilities are present, the two non-uniformities may act additively or subtractively, depending on the relationships between them.

In considering time effects, the behavior of several rheological models is examined. The uniform and non-uniform specimens are compared for creep (constant load), stress relaxation (constant extension) and stress-strain behavior at constant rates of loading and straining. To illustrate the applications possible with actual fibers, the creep behavior of wet wool fibers is briefly treated.
Wool Modification with Acid Anhydrides in Dimethylformamide
Authors: Koenig N.H.
Published: March 2007

The molecular structure of wool was modified by reactions with alkenylsuccinic and other anhydrides. This internal modification was accomplished under anhydrous condi tions in a special medium, dimethylformamide. Acid and alkali solubilities of the modi fied wool fabrics were interpreted as changes of the acid-base character of the wool and also in terms of' the anhydrite structure. Wool modified with long-chain alkenylsuccinic anhydrides had decreased strength but increased resistance to acid conditions and laundering shrinkage.
Wrinkling Behavior of Wool Fabrics
Authors: Katz H.J.
Published: March 2007

A multiple-pleat test has been developed for measuring the change in wrinkling properties of light to medium-weight wool fabrics following various finishing and chemical treatments. Accordion pleats are inserted in a fabric sample (6 in. X 3 in.) by two meshing sets of 30° wedges under uniform load. After holding under the required conditions, the sample is removed and the average pleat angle is measured optically at three intervals over a period of one day.

The complete wrinkling behavior is given by two terms, the percentage wrinkle recovery WR at a specified time (usually 15 min) and the recovery rate RR (WR change per unit log time).

A sequence of short conditioning and pleating times at 85% RH and 30°C, with recovery at 65% RH and 21°C, is used to develop a large wrinkling effect. The method requires fewer samples than conventional 180°-fold methods and is more versatile under the specified testing conditions. Results show that the change in wrinkling properties during storage or after steam-pressing must not be overlooked in interpreting the results.
Scale Angles for Wool and Mohair
Authors: Fourt Lyman
Published: March 2007

The light reflected from individual undyed wool fibers or from arrays of a few separate and parallel dyed fibers, with similar root-tip orientation, has been measured for a range of angles of illumination. With dyed fibers, there is a strong peak of reflectance at certain angles of illumination, which is shifted from one side of the mirror angle to the other, when root-tip orientation is reversed. This shift is four times the average angle between the scale surface and the fiber axis. It is independent of the fiber diameter in the material examined. The shift of the peak for wool ranges from 11° to 18° ; for mohair, from 5° to 7°, corresponding to average scale angles of 3.7° for wool and 1.5° for mohair.
An Experimental Investigation of Fiber Orientation and Some Properties of Needled Felts
Authors: Gårdmark L. , Mårtensson L.
Published: March 2007

The fiber orientation and fiber breakage were studied in a felt, needled in a laboratory needling machine, and the relationship between degree of needle penetration and felt thickness, density, strength, and air permeability was determined.
Observations on Properties of Partially Formylated Cottons; and Formyl Groups as Adsorption Sites for Direct Dyes
Authors: Goldthwait Charles F. , Kirby Rosa D.
Published: March 2007

Partially formylated cottons in the form of yarn or cloth absorbed up to two or three times as much direct dye as the original cottons, when samples of both were dyed in competition in the same bath. This higher absorption is shown to be due to the formyl groups acting as dyeing sites. The dye absorption increased with combined formic acid within the range studied, up to a D. S. of 0.35. Absorption was much higher by mercerized cotton than by unmercerized material of the same percentage combined formic acid. It is suggested that formyl groups substituted in cotton are more accessible to dyes than the hydroxyl groups of the original cotton, particularly if reacted with primary hydroxyl groups where they add to the lengths of side chains. Also, the carbonyl groups of the formates may have more attraction for the dyes than the original hydroxyl groups. The results appear to support the view that bonding of a dye to a substrate is a main factor in the direct dyeing of cellulose, as distinguished from "fixing" by aggregation alone of dye molecules within the fiber. It has been shown by indirect evidence from physical tests and special dyeing tests that the increased dye absorption is not due to any unusual swelling of the partially formylated cottons. Such tests indicate that cotton swells in formic acid about the same as in water, and that partially formylated cottons do not swell more in water than the original cottons. Incidental observations on the storage of partly formylated cottons showed losses of two-thirds of their combined formic acid in 5 years, while in other materials about 1% combined formic acid was retained after 25 years. Low-formylated cottons were unstable to boiling water in simulated direct dyebaths. This instability makes difficult, if not impossible, the establishment of a quantitative correlation between dye absorption and formyl content.
Substituted Propylene Urea in Conventional, Wet, and Moist Curing
Authors: Bille Heinz E. , Petersen Harro A.
Published: March 2007

The properties and scope of application of a new six-membered N-methylol ring compound, 4MO-5DM-PU (4-methoxy-5,5-dimethyl-NN'-dimethylolpropylene urea) are described. Special properties, such as chlorine resistance, stability to hydrolysis, light fastness, and reactivity, are discussed in the light of theoretical considerations and of the results obtained on practical application. It has been found that 4MO-5DM-PU produces chlorine-resistant, nonhydrolyzing, and lightfast finishes.

The reactivity of the product requires vigorous catalysts, but this does not adversely affect its use in numerous finishing processes. The procedures used in applying 4MO-5DM-PU by the conventional and wet and moist curing processes, as well as in permanent-press hnishing, are described. At the same time, the effects of additives, such as polyacrylates, polyolefins, and polyamides, in the various processes are dealt with. The versatility of 4MO-5DM-PU has produced a varicty of interesting results.
An Investigation of the Reversibility of N-Methylolacrylamide Cross Links on Cotton1
Authors: Hobart Stanley R.
Published: March 2007

N-Methylolacrylamide (NMA) was reacted reversibly in successive, acid-catalyzed and base-catalyzed steps to cross-link cotton cellulose. The occurrence of cross-linking was confirmed by development of cuene insolubility and wrinkle recovery. The ease of crease introduction or removal was used to indicate the extent of breaking and reforming the cross links on treatment of the ether linkages with the respective catalysts. It was found that good, durable creases could be introduced into flat NMA-cross-linked fabrics with either acidic or basic catalysis, the latter being slightly more effective. Removal of creases was only partially successful, regardless of the catalyst used, indicating that the sites of the ether linkages at the crease location were inaccessible to the catalyst. Breaking strengths and formaldehyde and nitrogen analyses were determined during these treatments.
Nonwoven Fabric Studies
Authors: Hearle J.W.S. , Newton A.
Published: March 2007

This paper describes an experimental investigation designed to assess the effect of the binder component on the physical properties of the nonwoven. Fabrics have been constructed in the laboratory with varying binder contents, and also the binder stiffness was varied. It is seen that in these samples an increase in either the binder content or binder stiffness results in an increase in both the tensile strength and initial modulus. The results are compared with those from fabrics made by linking the fiber network with a fiber solvent; this method results in a stiffer structure.
Fiber Engineering to Meet End Use Requirements1
Authors: Tippetts E.A.
Published: March 2007

Present-day knowledge of end use requirements for textile products has directed syn thetic fiber research to the development of a highly sophisticated ancillary technology . which is now in the early stages of commercial application. This new technology, in com bination with the older polymer and spinning technology for nylon, polyester, and acrylic fibers, achieves significantly new and improved levels of end use performance. The new technology is of major significance for the consumer and indeed is required to fully capitalize upon the basic properties afforded by the polymer used in the manu facture of the fiber. The examples chosen to illustrate the new approaches to engineering of new fibers cover such diverse end uses as hosiery, filament weaving yarns, carpets, and tires. All examples are based upon 66 nylon to emphasize the importance of the ancillary technology.
Fibers From Crystalline Hydrocarbon Polymers1
Authors: Bryant George M.
Published: March 2007

Properties of fibers derived from crystalline polymers of ethylene, propylene, 4-methyl- 1-pentene, and styrene are presented and contrasted. Polyethylene fiber properties depend markedly on the crystallinity or density of the polymer; although high-strength fibers can be made from linear polyethylene, resiliency properties are poor, tensile properties are highly time-dependent, and endurance under sustained loading is very poor. On the other hand, polypropylene fibers have good stress-endurance properties, excellent recovery from high extensions, and fair-to-good recovery properties at low strains; recovery at 'low strains is shown to depend on the extent of fiber orientation and annealing. Anoma lies in the change of the sonic modulus of polypropylene yarns during extension and relaxation are noted and interpreted in terms of structure changes in the crystalline phase. The high melting temperature of 235°C for poly(4-methyl-1-pentene) appears to be due to its low entropy of melting, and fibers from this polymer are characterized by low tenacity when tested at elevated temperatures. Crystalline polystyrene fibers have relatively good retention of tenacity at elevated temperatures and are characterized by excellent resiliency at low strains, good wash-wear characteristics in cotton blends, and low abrasion resistance.
The Effects of Various Combinations of Chemical and Physical Treatments on the Physical Properties of Cotton Yarns and Bundles
Authors: Egle Clifton J. , Grant James N. , Orr Rollin S.
Published: March 2007

The effects of tension during resin treatment on the physical properties of yarns and fibers that had received various combinations of pretreatments were investigated for Pima, Bobshaw, and Deltapine cottons. Pretreatments included scouring, mercerization, and acid degradation. Dimethylolethyleneurea (DMEU) resin was applied at 2 and 5% add-on. Relationships between bundle and yarn tensile properties were studied and found to have high correlation. Some evidence was found that degradation prior to tension during resin curing has the effect of preventing strength losses due to cross linking. Degradation was observed to inhibit relative elongation losses in yarns due to tension curing. Degradation caused lower values of toughness whereas mercerization prevented such losses.
Iodide Ion Catalysis in the Benzylation of Cotton Cellulose
Authors: Wade Ricardo H. , Welch Clark M.
Published: March 2007

The presence of alkali metal iodides accelerated the reaction of benzyl chloride with alkali cellulose. The alkali metal iodide was added to the mercerizing alkali used to activate the cotton yarn. The degree of benzylation observed with iodide present was 74% to 110% greater than with iodide absent. A D.S. of 0.7 could readily be obtained within a reaction period of thirty minutes at 115°C. The breaking strength retention at this D.S. was 93% to 119%, based on unmercerized, untreated yarn. Other salts tended to retard benzylation. Borax and neutralized boric acid were ineffective as catalysts, contrary to previous reports. Catalysis by iodide salts is considered to be due to the in situ formation of benzyl iodide from benzyl chloride within the cellulose fibers, the organic iodide being a more active alkylating agent than the chloride. Hydrotropic effects of the alkali iodides appear to be of secondary importance in the catalysis.
Spinning of Cotton Yarns from Cross-Linked and Untreated Fibers on the Woolen System and Their Performance in Winter-Weight Fabrics 1
Authors: Valko Emery I. , Angelo Paul J.
Published: March 2007

Cotton cellulose in form of loose bleached fiber was cross-linked with dimethylol ethylene urea. No serious difficulties were encountered, but the cross-linked fiber was brittle and suffered extensive damage when carded on the woolen system. The yarn so produced was extremely weak, although it exhibited higher bulk compressional resilience than yarn spun from untreated fiber.

Yarn spun on the woolen system from bleached cotton fiber exhibited high bulk, loft, and strength. Treating the yarn with DMEU reduced considerably its strength but increased its resilience.

Winter-weight fabrics could be produced from untreated cotton yarn and from cotton yarn spun from blends of untreated and DMEU-treated fibers. The hand of the fabric woven from the blend was superior to the hand of untreated fabrics and also of fabrics which were treated with DMEU after weaving.
Studies on Luster in Textiles
Authors: Prakash Jai , Oka P.G. , Iyengar R.L.N.
Published: March 2007

By using a specially designed sample holder for gripping the aligned and parallelized cotton fibers in conjunction with locally fabricated lustermeter, it has been possible to measure accurately the changes in the luster behavior of cotton fibers on slack merceri zation followed by stretching to different degrees.

The differential response of cotton fibers of ten varieties to the enhancement of luster as a result of slack mercerization followed by stretching to different extents has been related to the corresponding changes in the gross morphological structure and the molecular orientation. The degree of shape improvement between unmercerized and mercerized-unstretched state of a cotton has been found to be much greater than the shape improvement from mercerized-unstretched to mercerized-stretched state, and yet the development of luster has been found to be far more pronounced in the latter case than in the former. Attempts have been made to explain this behavior in terms of the changes in the molecular orientation, surface characteristics, and convolution geometry of the cotton fibers.
Carpet Performance Evaluation
Authors: Laughlin Kenneth C. , Cusick Gordon E.
Published: March 2007

Thirty two tufted carpets, representing variations in fiber content, pile weight, and cut and loop-pile construction were studied for stress-strain behavior under cyclic loading to 12 lb/in.2 on an Instron tensile tester. Results are presented conventionally in terms of compression, recovery, matting, and resilience. In addition, a relationship, which appears to be responsive mainly to the type of fiber in the pile yarn, was developed between the compressive force per unit weight of pile yarn and the percent compression of the pile. On this basis, no major difference was found in the relative stress-strain behavior of the carpets before and after exposure to 100,000 revolutions of the Tetrapod Walker.
Quality Assessment of Jute and Mesta Yarns from Their Fiber Properties
Authors: Bandyopadhyay S.B.
Published: March 2007

Tenacity of jute and mesta yarns has been related to bundle tenacity and fineness, measured on simple instruments, and regression equations have been obtained. The multiple correlation coefficient is of the order of 0.8.
Oblique Strain Markings in Oriented Polymers
Authors: Bosley D.E.
Published: March 2007

A brief review of the literature on strain markings is followed by a discussion of additional experiments showing the effects of pretreatment and environment on the occurrence of oblique strain marks in poly(ethylene terephthalate) fibers in terms of the implications of these effects on models of polymer fine structure. Oblique strain marks are concluded to be abrupt shear deformations commonly known as Lüders' lines, occurring mainly in compression in a manner analogous to neck formation in tension. The details of their formation are inconsistent with a metallurgical analogy for polymer deformation. The morphology of these markings is discussed and compared with transverse strain markings which often accompany tensile strains.
Breakage Models and Measuring Techniques for Fiber. Weight-Length Distributions
Authors: Tallant John D. , Pittman Robert A.
Published: March 2007

Previously developed number-frequency equations are translated into their weight- frequency counterparts. A solution is developed for the problem of fiber-length distri bution to be expected when a sliver or similar textile structure, with straight fibers, is cut systematically. A double-clamping technique is described which permits the determina tion of the weight-frequency distribution and weight-mean length of the fiber population in the sliver, with the same assumption that the fibers are straight and parallel to the structure axis. It is shown that, if the fibers are not straight and parallel, the same technique measures the projection of the fibers along the structure axis. Simple methods for measuring the projected length are described and data are represented showing the change in projected length as a typical cotton proceeds from card sliver through roving. The basic mathematical equations for the Lindsley combing ratio are derived, and it is shown that a modification of the Lindsley technique can also yield the projected mean length.
Reaction Mechanisms, Structure, and Properties of Methylol Compounds in Cross-Linking Cotton1
Authors: Petersen H.
Published: March 2007

Kinetic and thermodynamic studies on the formation and dissociation of N-methylol compounds, as well as a study of their equilibrium states in relation to concentration, temperature, and catalysts, on the cross-linking of N-methylol and N-alkoxymethyl compounds with nucleophilic reactants, such as the hydroxy groups of cellulose, on the stability of the N-alkoxymethyl compounds in alkaline and acid media, and on the processes involved in chlorine retention, have led to an explanation of the mechanisms underlying these reactions, and to an understanding of the influence of such factors as electron density at the nitrogen atom (as determined by the methylolation rate in general or by the carbonyl wave number. in the case of ureas and acid amides), basic centers, possible steric hindrance and anchimeric groups on the application properties of these substances. Regular relationships have been established between their chemical consti tution and properties, which make possible a more reliable prediction of the scope of the effects obtainable with methylol compounds.
Study of Theories of Fiber Migration—Need for More Fundamental Approach and Further Studies
Authors: El-Behery Hassan M.
Published: March 2007

The study of yarn structure and positioning of the constituent fibers to form a continuous strand has attracted the attention of many workers who have used an idealized helical structure as a basis for these studies. The existence of this structure has been criticized as being unuseful and not manufacturable. Studies of the actual arrangement of fibers in the yarn have been carried out and different theories explaining the behavior of fibers in the process of yarn formation have been given. In this paper, a study and comparison of these theories is carried out illustrating the agreement and controversy between them. The factors that affect the position of the fiber in the yarn are outlined and discussed with regard to fiber, yarn, and processing factors to assist those dealing with blended yarns. Suggestions are advanced for further, more funda mental studies.
Improved Cotton Durable Press by Wet Fixation. Laboratory-Mill Correlations1
Authors: Baitinger William F. , Nakajima William , DePaolo George
Published: March 2007

Previous experimental treatment of the theoretical aspects of the wet-fixation tech nique has led to conclusions regarding the nature of the resins and reactants used, their interactions in the process, and the balancing of cross-linking for durable-press per formance and polymerization for physical-property retention. Subsequently, laboratory trials were run which were designed to elucidate and test the critical variables of the process, the ultimate objective being successful translation of the process to the mill.

Recognizing that fabric type is a particularly critical variable, work to date has been limited to three fabrics-100% cotton corduroy, 100% cotton twill, and cotton broad- cloth. The following variables were considered on a laboratory basis—bath concentra tion of resin and reactant, time and temperature of wet fixation, concentration and nature of topping catalyst, and pressing and final cure. The results are analyzed by means of wrinkle recovery, physical properties, appearance and crease ratings, and resin analysis. Optimal selected laboratory conditions have been duplicated on a mill scale and, for samples examined to date, the correlation is very good.

The following conclusions can be drawn from this work: for a particular fabric, e.g., corduroy or cotton twill, the "wet-fixation" technique provides an excellent level of durable-press performance with high physical-property retention, including significantly improved abrasion resistance; some latitude exists in the "wet-fixation" step, permitting either high-temperature/short-time reaction or room-temperature/longer-time batching; catalyzation, pressing and curing play a significant role in end-result performance, and the controlled translation of laboratory trials to mill trials has been successfully accomplished.