Available online at http://www.urpjournals.com International Journal of Fiber and Textile Research Universal Research Publications. All rights reserved ISSN 2277-7156 Original Article AN EVALUATION FOR COTTON FIBER LENGTH DISTRIBUTION MEASUREMENTS OF DIFFERENT METHODS Ibrahim A. M. Ebaido Cotton Research Institute (CRI), Agricultural Research Center (ARC), Giza, Egypt Email:[email protected] Received 01 January 2014; accepted 06 March 2014 Abstract The seven Egyptian commercial cotton varieties, which have wide range of fiber length distribution, were used for the purpose of characterization of the relationship between fiber length parameter of cotton obtained from both the conventional as well as the hi-tech instruments to give an idea of the similarity in fiber length distributions and their effectiveness. The instruments used to measure fiber length distribution measurements include Suter-Webb array, AFIS (by number and by weight) and HVI (USDA and ICC modes). Comparisons between the three methods indicate that the measurements of mean length correlate well with each other; and also longer fibers length measurements. Whereas length uniformity and short fibers show weak associations among their measurements. Discriminations of mean length and longer fibers are similar among the samples for three methods. However, Suter-Webb array shows the greater discrimination of length uniformity and short fibers than HVI and AFIS. Although the tedious Suter-Webb array method may yield sharper distinctions in length distribution measurements among different cottons; AFIS and HVI give strongly related measures of mean length and longer fibers. Whereas, length uniformity and short fibers measurements still need some efforts to gain realistic. © 2014 Universal Research Publications. All rights reserved Keywords: AFIS, Cotton, Fiber Length Distribution, HVI, Suter-Webb INTRODUCTION Fiber length is critical for textile processing and varies greatly for different cottons due to genetic differences [1]. Measuring a fiber beard instead of individual fibers provides a rapid account for those fiber length parameters, for example, the widely used High Volume Instrument (HVI) system [2]. In HVI testing, the specimen fibers are picked up by the needles of a comb/clamp through holes of the HVI Fibrosampler. The collected specimen fibers are in the form of a tapered beard. The beard is brushed and combed to remove loose fibers and fiber crimp. By scanning light attenuation at each length (from the tip of the longest fiber in the beard to the baseline of the clamp), the instrument determines the fiber mass at each length of the beard. The mass-length curve obtained from measuring this tapered beard is called a fibrogram. The original theory of the fibrogram as developed by [3] and [4] has served as the basis of subsequent cotton length measurement methods based on such tapered fiber beards. Following [4] pioneering work, various developments have been made. [5] Generated fiber length distributions in discrete form cotton fiber fibrograms. 5 Those generated distributions were presented as graphical bar charts, not as mathematic functions. [6] Provided a comprehensive appraisal and developed a series of equations for computing different fiber length parameters from fibrograms. [7] Described the basic ideas of the fibrogram theory starting from a frequency diagram and establishing geometrical and probabilistic interpretations for single fiber length, two fiber length and multiple fiber length populations. [8] Showed that the mean length and the proportion of fibers can be obtained from the fibrogram. [9] Applied a new approach to generate the fibrogram from the length array data similar to [7] method. They assumed a random catching and holding of fibers within each of the length groups generating a triangular distribution by relative weight for each length group. [10] Discussed the concept of short fibers content (SFC) and showed relationships between SFC and other fibers length parameters and functions. Later they determined empirical relationships between SFC and the HVI length. The most fundamental, direct (and tedious) measure of fiber length distribution is the Suter-Webb array method in which a comb-sorting International Journal of Fiber and Textile Research 2014; 4(1): 5-11 technique is used to segregate the fibers into length groups, each of which are weighed on an analytical balance. The AFIS (Advanced Fiber Information System) instrument is also a direct measurement of fiber length distribution, as it utilizes a mechanical opener to inject individual fibers into a rapid air stream where the length of each fiber can be measured a high speed electro/optic system [11]. There is some legitimate concern that the AFIS mechanical opener/individualizer causes some fiber breakage [12]. Also, many of the fibers passing through the instrument are not presented in a manner that enables measurement; therefore, these fibers are excluded from the results. The fiber breakage makes getting repeatable measurements among instruments very difficult, while the exclusion of various fibers from the sample raises (unanswered) questions about possible bias in the measurement. Recent research shows that the parameters commonly used to characterize the fiber length (mean length, short fiber content…) present multiple shortcomings and are for instance not usable by cotton breeders to improve length distribution, or by ginners and textile manufacturers to reliably optimize the fiber behavior during processing [13], [14], [15], [16] and [17]. The present research seeks to overcome this lack of reliable parameters by acquiring a better understanding of the cotton fiber length alterations. The approach is to consider the process from the seed to the yarn and to establish parametric models describing the fiber length distribution and its alterations [18]. With such adequate parameterization of the length distribution, breeders, agronomist and processors will have access to more accurate information allowing interpretation and use of the distribution data. Because of different methods are used for the determination of the same parameters, it is expected that the results for a particular parameter expressed by different methods agree numerically within a narrow tolerance zone. If not, at least they should follow the same trend. The present investigation intends to correlate the same fiber length parameter of cotton obtained from both the conventional as well as the hi-tech instruments, with each other to give an idea of the similarity or variations in fiber length distributions obtained from various instruments. And investigate the relationship between these distributions and the true fiber length distribution. 2. MATERIALS AND METHODS The seven Egyptian commercial cotton varieties, which have wide range of fiber length, were used for the study. Four of these varieties belong to the extra-long staple category, i.e., Giza 70, Giza 87, Giza 88 and Giza 92. While the other three ones belong to the long staple class, i.e., Giza 86, Giza 80 and Giza 90. The fiber length parameters were obtained on instruments located at: 2.1. Cotton Research Institute (CRI) in Giza, Egypt After sampling, the hand-made slivers were prepared, loose cotton lint was used for the High Volume Instrument (HVI) testing [19], which provides measurement of several characteristics, but only the fiber length parameters according to USDA calibration, viz. upper half mean (UHM), mean length (ML), uniformity index (UI) and short 6 fiber index (SFI), have been dealt with in the paper. While hand-made slivers were used for testing fiber length distribution by weight with Suter-Webb array method [19], which provides upper quartile length (UQL), mean length (ML), short fiber content (SFC) and coefficient of variation (CV %) which is reflects regularity (how the uniform of length distribution). Before testing, cotton samples were conditioned for at least 48 hours at 65% ± 2% RH and 21o C ± 2ºC prior to testing; 2.2. South India Textile Research Association (SITRA) in Coimbatore, India After sampling, the hand-made slivers were prepared, loose cotton lint was used for HVI testing [19], which provides measurement of 2.5 % SL, uniformity ratio (UR) and short fiber index (SFI) according to International Calibration Cotton (ICC) mode. While hand-made slivers were used for testing fiber length distribution with the AFIS (Advanced Fiber Information System) according to [19], which used to determine fiber length parameters by weight and by number (5000 fibers were used for measurements per sample), i.e., UQL, 5 % SL, ML, SFC and CV % which gave the same interpretation in Suter-Webb about length regularity (uniformity). All the tests were carried out under standard atmospheric conditions of 65 % ± 2 % RH and 27º C ± 2º C temperature. All data gathered were computed using XLSTAT software to compare mean values of fiber length distributions; descriptive statistics obtained from different instruments and correlate each one of these distributions with others. 2.3. INSTRUMENTS 2.3.1. High Volume Instrument (HVI) High volume instrument (HVI) system provides measurement of fiber length, length uniformity and short fiber (fibers shorter than half inch) through measures the light intensity that goes through a sample of fibers. The less amount of light can go through the sample, the longer the fibers are (use of light in the distribution of staple length measurements), and therefore such measurement leads to obtaining a chart called length-frequency curve or fibrogram beard (Fig. 1). That chart (fibrogram) presenting the relationship between the amount of light going through the sample and the fiber length was corresponding to this value. These values or parameters is usually defined depending on the standard samples used in the calibration of the HVI to mean lengths, e.g. the upper half mean length (UHML), which is the mean length of the longer half (50%) of the fiber, and the mean length (ML) are more commonly used since they describe the mean of all or a set portion of fibers represented in the fibrogram, these parameters used after response to a USDA proposal considered at the triennial conference in 1995, and called USDA's calibration standards for HVI measurements after incorporated into the Universal Standards Agreement. The other parameters used in the expression for the length of staple is Span lengths (SL) or International Calibration Cotton (ICC) mode, which came about as a result of a technical shortcoming in the ability of the first digital Fibrograph to graphically run a tangent to the fibrogram, represent fiber extension distances, e.g. the 2.5 % SL International Journal of Fiber and Textile Research 2014; 4(1): 5-11 represents the distance the longest 2.5 % of fibers extended from the comb. Length uniformity is expressed either as the uniformity index or uniformity ratio. Both terms are ratios of measurements from the fibrogram, where uniformity index refers to the ratio between the mean length and the upper half mean length and the uniformity ratio refers to the ratio of the 50% SL to the 2.5% SL. The most common definition of short fiber is the proportion by mass of fiber shorter than one half inch. Short fiber is not measured directly by any instrument employed in HVI lines. Instead short fiber content (SFC), short fiber index (SFI) is estimated indirectly using the fibrogram measurements of UHML and ML or 2.5% SL and 50% SL as the main variables in prediction equations. Fig1. Typical Fibrogram HVI length distribution 2.3.2. Suter-Webb array (SW) This method consists of a bed of upright and parallel combs which control the fibers and arranged it in the form of an array of uniform density in the descending order of length. In this way enable the sample (fibers) to be fractionated into length groups for determining cumulative fiber length distribution by weight in parameters upper quartile length (UQL), mean length (ML) and % short fibers (SFC) as illustrated in Fig. 2 and dispersion percentage which is expressed as (CV%). The disadvantages of this device are time consuming (2 hrs per sample) and calls for considerable operator skill in sampling and preparing the diagram (Fig. 2). Fig2. Short fiber content and upper quartile length in the beard of staple 2.3.3. Advanced Fiber Information System (AFIS) This instrument measures length, alongside it also measures fineness, maturity, circularity, etc. of each fiber fed, and from the data so obtained provides average length of individual fibers in a sliver fed to the system, as also the length distribution both by number and weight, this 7 distribution gives the following parameters effective length (UQL), Mean length (ML), % short fibers (SFC) and dispersion percentage which is expressed as (CV%) after measuring the individual fiber length for a selected weight and number of fibers which can be varied between 1000 and 10000. Other parameters the instrument can measure are immature fiber content, neps/g and percentage of dust and trash. 2.4. DEFINITIONS The fiber length can be described by its distribution by number that expresses the probability of occurrence of a fiber within the length group, or it can be described by its distribution by weight that expresses the weight of fibers in each length group. 1. Mean length (ML) The mean length ML is obtained by summing the product of fiber length and its weight, then dividing by the total weight of the fibers. 2. Coefficient of fiber length variation (CV %) The coefficient of variation of fiber length CV % is the ratio of σ divided by the mean length ML: CV % = (σ /ML) × 100. Where σ is standard deviation of fiber length. 3. Upper quartile length (UQL) The upper quartile length is defined as the length that is exceeded by 25% of fibers by weight. 4. Upper half mean length (UHML) The UHML is the average length of the longest one-half of the fibers 5. Span length (SL) The percentage span length % indicates the percentage of fibers that extends a specified distance or longer. The 2.5 % and 50 % are the most commonly used by industry. 6. Uniformity index (UI %) UI % is the ratio of the mean length divided by the upper half-mean length. It is a measure of the uniformity of fiber lengths in the sample expressed as a percent: UI % = (ML / UHML) × 100. 7. Uniformity ratio (UR %) UR % is the ratio of the 50% span length to the 2.5 % span length. It is a smaller value than the UI % by a factor close to 1.8 UR % = (50 % SL / 2.5 % SL) × 100. 8. Short fiber content (SFC %) SFC % is the percentage by weight of fibers less than one half inch (12.7 mm). 3. RESULTS AND DISCUSION Fiber length in a cotton sample has length distribution corresponding to variation in fiber length of individual fibers. If one can measure separately all the individual fibers present in a sample, he would be able to get the true distribution of the fiber length. But this is almost impossible. However, a true representative tuft constituting thousands of fibers taken from the sample can also give a distribution almost similar to the true distribution. Moreover, the measurements of lengths of individual fibers for a few thousand fibers are also difficult and time consuming, though not impossible. The idea of carrying out tests for measurement of fiber length distributions is to get the most accurate and reproducible results. Reproducibility of results generally depends on proper sampling and the International Journal of Fiber and Textile Research 2014; 4(1): 5-11 Table 1. Glossary of variable names SW-ML Suter-Webb mean length (mm) SW-UQL Suter-Webb upper quartile length (mm) SW-CV Coefficient of variation of Suter-Webb mean length (%) SW-SFC Suter-Webb short fiber content (%) HVI-ML HVI mean length according to USDA mode (mm) HVI-50%SL HVI 50% span length according to ICC mode (mm) HVI-UHM HVI upper half mean length according to USDA mode (mm) HVI-2.5%SL HVI 2.5% span length according to ICC mode (mm) HVI-UI HVI length uniformity according to USDA mode (%) HVI-UR HVI length uniformity according to ICC mode (%) HVI-SFI(U) HVI short fiber index according to USDA mode (%) HVI-SFI(I) HVI short fiber index according to ICC mode (%) AFIS-MLN AFIS mean length by number (mm) AFIS-MLW AFIS mean length by weight (mm) AFIS-5%SL AFIS 5 % span length by number (mm) AFIS-UQL AFIS upper quartile length by weight (mm) AFIS-NCV Coefficient of variation of AFIS mean length by number (%) AFIS-WCV Coefficient of variation of AFIS mean length by weight (%) AFIS-SFCN AFIS short fiber content by number (%) AFIS-SFCW AFIS short fiber content by weight (%) inherent variability in the material. But the accuracy of measurement of a parameter depends on the physical principals used in the test method. The following discussion shows limitations in determination of fiber length distribution using Suter-Webb array, HVI and AFIS. These limitations are mainly due to the limitation of physical test methods used for these determinations. 3.1. Mean length and 50 % span length measurements A compilation of the significant statistical parameters of the five mean length measurements is given in Table 2. These include: minimum (MIN); maximum (MAX); mean; standard deviation (SD) and coefficient of variation (CV=100X SD/Mean). The mean values for mean length for each measurement for all samples range between 24.34 and 29.7 mm; whereas, 50 % SL ranged less between 13.07 and 20.2 mm. The 50 % SL is the least discriminating having the smallest SD (1.17) and CV % (7.62). The AFISMLW is the most sensitive with the largest range of values (24.3 – 32.1 mm) and the greatest SD (2.9) and CV % (9.91). Table 2. Overall results of mean length and 50% SL measures SW ML (mm) ML HVI 50%SL AFIS MLN MLW MIN 25.1 25.22 13.07 20.2 24.3 MAX 33.9 32.16 16.65 27.4 32.1 Mean 29.7 29.13 15.35 24.34 29.24 SD 2.33 2.24 1.17 2.34 2.9 CV% 7.84 7.68 7.62 9.61 9.91 In Figure 3, comparing the mean length and 50 % SL measurements for the three instruments in this study. Each set of data was sorted from the smallest to largest values. 8 The AFIS-MLW has the high variation and 50 % SL is the lowest, which seemed to be flat. It needed to be pointed out that the HVI-ML and AFIS-MLW data tend to track SWML better. International Journal of Fiber and Textile Research 2014; 4(1): 5-11 The Figure 4 illustrates the high values and largest range of the AVIS-UQL; while the HVI measures (UHM and 2.5% SL) show the smaller ranges. The correlation matrix (Pearson's R-values) shown in Table 3 indicates the relationship among mean length and 50 % SL measures. The inter-correlations between all five variables are high significant (0.702 – 0.965). It is not surprising that the highest R-value (0.965) is between AFIS-MLW and AFIS-MLN. The lowest correlation value is that of SW-ML with HVI-50%SL and HVI-ML (0.702 and 0.738 respectively) Table 3. Correlation coefficients among mean length and 50% SL measures AFIS-MLW AFISMLN HVI-50% SL HVI-ML SW-ML HVI-ML HVI-50% SL AFIS-MLN 0.801** 0.786** 0.702** 0.738** 0.923** 0.870** 0.923** 0.891** 0.859** 0.965** Because overall textile performance is largely dictated by longer fibers in a distribution, it is appropriate also to consider the longer fiber data. Suter-Webb and AFIS both estimate the upper quartile length and 5 % SL, whereas HVI, depending on fibrogram theory, measures upper half mean (USDA mode) or 2.5 % SL (ICC mode). Descriptive statistics for the measures of the longer fibers length obtained from the three instruments are shown in Table 4. The mean values for longer fibers length differ from method (instrument) to another. The highest measure is AFIS-5%SL (40.97 mm), while the lowest is the HVI2.5%SL (32.51 mm). The SW-UQL value (38.03 mm) is higher than the AFIS-UQL value (34.63 mm). It is clearly obvious; the AFIS-UQL is the most sensitive with the largest SD (3.63) and CV % (9.8); whereas the HVI-UHM is the least discriminating having the smallest SD (2.33) and CV % (6.9). Table 4. Overall results of the longer fibers length measures SW-UQL MIN MAX Mean SD CV % 9 32.80 41.92 38.03 2.89 7.61 Table 5. Correlation coefficients among longer fiber length measures AFIS-UQL AFIS-5%SL HVI-2.5%SL HVI-UHM 3.2. Longer fibers length measurements HVI UHM 2.5%SL 29.40 27.43 36.50 36.20 33.75 32.51 2.33 2.7 6.90 8.3 The correlation matrix of the Pearson correlations among the five measures indicates the inter-correlations between all five measures are quite high (greater than 0.90). It is not surprising that the higher R-values are between the AFISUQL and AFIS-5%SL (0.981), and also between HVIUHM and HVI-2.5%SL (0.968). UQL 35.18 44.20 40.97 3.4 8.41 28.81 38.72 34.63 3.63 9.8 HVI-UHM 0.915** 0.928** 0.917** 0.914** 0.944** 0.948** 0.968** HVI 2.5%SL AFIS 5% SL 0.910** 0.925** 0.981** 3.3. Fiber length uniformity As there are various ways of expressing the length uniformity of fibers, it is difficult to compare the length uniformity measures of different methods (instruments).Descriptive statistics for the fiber length uniformity measures obtained from the three instruments are shown in Table 6. The mean values of length uniformity exhibit big differences among each of the five measurements. The HVI-UI is the highest measure of length uniformity (86.2) %, while the SW-CV is the lowest measure (18.7 %). The largest variation is of the SW-CV which has the highest SD (3.56) and CV % (12.03); whereas the HVI-UR exhibits the narrowest range with lowest SD (0.73) and CV % (1.52). Generally, the low values of SD for the five measurements obvious the low variations for those measurements. Table 6. Overall results of fiber length uniformity measures HVI AFIS 5%SL SW-UQL MIN MAX Mean SD CV % AFIS SW-CV UI UR 12.9 83 46 40.2 29.1 26.5 89.2 48.7 45.6 34.4 18.7 86.2 47.2 42.7 31.9 3.56 1.73 0.73 1.34 1.47 12.03 2 1.52 International Journal of Fiber and Textile Research 2014; 4(1): 5-11 NCV 3.14 WCV 4.61 Figure 5 illustrated to compare the five measures of length uniformity measurement. The SW-CV exhibits the largest range and the lowest values; whereas the HVI-UI has the highest values. The HVI measures, especially uniformity ratio (UR) have smaller variations; so seemed to be flat. The inter-correlations among all fiber length uniformity measurements are shown in Table 7. Looking at the correlation matrix, it is found that most the measurements of fiber length uniformity show insignificant correlations; except for the significant and positive correlation coefficients of AFIS-WCV with each of AFIS-NCV (0.468) and HVI-UR (0.367). And also, the SW-CV exhibit significant and negative correlation with HVI-UI (-0.439). This means that the HVI-UI may be indicative of length uniformity than that obtained from AFIS. Table 7. Correlation coefficients among fiber length uniformity measures AFISWCV AFIS-NCV HVI-UR HVI-UI SW-CV 0.075 - 0.032 - 0.074 - 0.439* HVI-UI - 0.158 0.276 - 0.120 HVI-UR 0.367* 0.014 AFIS-NCV 0.468* 3.4. Short fibers measurements Descriptive statistics for the five measures of short fibers included in this study are shown in Table 8. These include short fibers as measured by Suter-Webb array (SFC), HVI (SFI) in two modes [USDA (U) & ICC (I)] and AFIS (SFC) by number (N) and by weight (W). The mean values for short fibers for each measurement range between 4.94 % (AFIS-SFCW) and 15.59 % (AFIS-SFCN). The HVISFI(I) is the least discriminating having the smallest SD (0.40) and the narrowest range of values (4.51 – 6.16 %). The SW-SFC is the most sensitive with the highest SD (3.13) and the largest range of values (3.13 – 15.51%). It is needed to point out that the high values of % CV values for SW-SFC (39.17) and AFIS-SFCW (25.3) indicate the large variation in these measures. Figure 6 illustrates the comparison among the five measures of short fibers measurement. The high values of short fibers are for AFIS-SFCN with moderate range; whereas the largest range is for SW-SFC. Each of HVI-SFI (I) and HVI-SFI (U) data tend to track SW-SFC and AFISSFCW better. The correlation matrix shown in Table 9 indicates the relationships between each of the five measures of short fibers. The correlation coefficient values among these measurements are moderate (range between 0.276 and 0.862). The high significant correlation values are of SWSFC with each of AFIS-SFCN, AFIS-SFCW and HVI-SFI (I). And also between the two measures of AFIS (SFCN and SFCW). The correlation coefficient between measures of the two modes of HVI is significant. Only the AFISSFCN and HVI-SFI (U) correlate insignificantly. Generally these relationships mean that, measurements of AFIS (N&W) and HVI (ICC mode) could be considering represent measurement for short fiber instead of SuterWebb array, but to some extent. Table 9. Correlation measures SWSFC AFIS0.636** SFCW 0.788** AFIS0.576** SFCN 0.333* HVISFI(I) HVISFI(U) coefficients among short fiber HVISFI(U) 0.367* 0.276 0.441* HVISFI(I) 0.364* 0.441* AFISSFCN 0.862** SUMMARY AND CONCLUSIONS This investigation aimed to characterization of the relationship between fiber length measurements of cotton obtained from both the conventional as well as the hi-tech Table 8. Overall results of short fiber measures instruments to give an idea of the similarity in fiber length SW HVI AFIS distributions and their effectiveness. The three methods SFC SFI(U) SFCN SFCW studied included using the Suter-Webb array method as SFI(I) compared with AFIS and HVI in two modes (USDA and MIN 2.29 5.72 4.51 12.11 3.2 ICC). MAX 15.51 7.41 6.16 18.62 8.45 Our results lead to the following conclusions: (1) The Mean distributions of mean fiber lengths are similar for Suter7.83 6.41 5.45 15.59 4.94 SD Webb array and HVI modes, with Suter-Webb 3.13 0.43 0.40 1.9 1.25 CV % differentiating narrowly more than HVI among the lots, 39.17 6.65 7.4 13 25.3 with low values of 50 % SL. Whereas, the AFIS mean International Journal of Fiber and Textile Research 2014; 4(1): 5-11 10 length by weight and by number produced wider distribution than Suter-Webb There is a strong degree of linear association among the pairs of measurements (0.702< r < 0.965). (2) The distributions of longer fibers length measurements are similar, except for UHM which is lowest, with AFIS-UQL by weight producing somewhat the widest distribution of values, with highest values of AFIS5%SL. The linear associations among all measurements of longer fibers length are strong (r ≤ 0.91). (3) Although the Suter-Webb array exhibited the lowest value of fiber length uniformity measurement, it is produced a wider distribution than either HVI or AFIS. That is, Suter-Webb differentiated the lots more than did the high-tech machines, especially compared to HVI length uniformity measurements for lots. However, there is a weak degree of linear association between the pairs of short fiber measurements (0.014 < r < 0.468). (4) The Suter-Webb array produced a wider distribution of short fibers measurement than either HVI or AFIS. That is, Suter-Webb differentiated the lots more than did the machine methods, especially compared to HVI short fibers measurements for lots with low values of SFC. Therewith, AFIS-SFC by weight seemed to be similar SWSFC, to some extent. There is a moderate degree of linear association between the pairs of short fibers measurements (0.276 < r < 0.862). (5) Although the tedious Suter-Webb array method may yield sharper distinctions in length distribution measurements among different cottons; AFIS and HVI give strongly related measures of mean length and longer fibers. Whereas, length uniformity and short fibers measurements still need some efforts to gain realistic. (6) Given the associations among similar fiber length properties produced by the three methods, there is little reason to perform the expensive and tedious Suter-Webb array in order to obtain length distribution measures if either HVI or AFIS data are available. Likewise, if length measurements have been made by one instrument, little additional information about fiber length is gained by obtaining measurements from the other one. 4. REFERENCES 1. 2. 3. 4. 5. 6. 7. 8. 9. 10. 11. 12. 13. 14. 15. 16. A. Basra. Cotton Fibers: Developmental Biology Quality Improvement, and Textile Processing. Food Products Press, Binghamton, NY. (2000). M. Suh and P.E. Sasser. Technological and Economic 17. Impact of HVI on Cotton and Cotton Textile Industries. Journal of the Textile Institute Part 3, 87:43-59, (1996). K.L. Hertel. An optical method for the length analysis of cotton fibers. Textile Research Journal. 6:331-339, (1936). K.L. Hertel. A method of fiber-length analysis using 18. the fibrograph. Textile Research Journal. 10:510-525, (1940). R.S. Krowicki, D.P. Thibodaux, and K.E. Duckett. 19. Generating fiber length distribution from the fibrogram. Textile Research Journal. 66:306-310, (1996). J.L. Woo. An appraisal of the length measures used for cotton fibers. Journal of the Textile Institute, 58, 557– 572, (1967). C. B. Landstreet. the Fibrogram: Its Concept and Use in Measuring Cotton Fiber Length, Textile, Bull., 87, No. 4, 54-57, (1961). R. S. Krowicki, J. M. Hemstreet, and K. E. Dukett. A Different Approach to Generating the Fibrogram from Fiber-Length-Array Data, Part I: Theory, J. Text. Int., 88 Part I, No. 1, 1-5, (1997). R. S. Krowicki, J. M. Hemstreet, and K. E. Dukett. A Different Approach to Generating the Fibrogram from Fiber-Length-Array Data, Part II: Application, J. Tex. Int., 89 Part I, No. 1, 1-8, (1998). M. I. Zeidman, S. K. Batra, and P.Sasser. Determining Short Fiber Content in Cotton, Part I: Some Theoretical Fundamentals, Textile Res. J. 61 (1): 2130, (1991). C.K. Bragg and F.M. Shofner. Rapid, Direct Measurement of Short Fiber Content. Textile Res. J. 63(3), 171-176, (1993). X. Cui, T.A. Calamari and Jr. Robert. An investigation of cotton fiber lengths measured by HVI and AFIS. The 10th EFS system research forum proceedings. 115-123, (1997). K. Q. Robert and L. J. Blanchard. Cotton Cleanability. Part I: Modeling Fiber Breakage. Textile Res. J., 67 (6): 417-42, (1997). K. Q. Robert, J. B. Price and X.Cui. Cotton Cleanability – Part II: Effect of Simple Random Breakage on Fiber Length Distribution. Textile Res. J., 70 (2): 108-115, (2000). K. Q. Robert and X. Cui. Analysis of the Fraction of Broken Fibers in Cotton. Cotton Incorporated Fourteenth Annual Engineered Fiber Selection System Conference Proceedings and Fourteenth Annual Engineered Fiber Selection System Research Forum Proceedings, pp.: 47-53 (June 11-13), (2001). M. Krifa. AFIS Length Distribution in Cotton Spinning Preparation. Beltwide Cotton Conferences – Cotton Quality Measurements / Utilization, January 5-9, San Antonio, Tx., National Cotton Council of America. Memphis, TN, USA, pp. 3072-3076, (2004). M. Krifa and E. Hequet. Experimental Assessment of Cotton Fiber Behavior During Opening and Cleaning. Proceedings of the Beltwide Cotton Conferences – Cotton Utilization / Textile Technology Symposium, January 4-7, New Orleans, LA, National Cotton Council of America. Memphis, TN, USA, pp. 27132716, (2005). M. Krifa. Fiber Length Distribution in Cotton Processing: Dominant Features and Interaction Effects. Textile Research Journal. 76:426-435, (2006). ASTM. American Society for Testing and Materials. Designation, (D: 1776-98, D: 1444-05, D: 4603-86, D: 5866-95) Test Methods, Philadelphia 3, Pa, U.S.A (2005). Source of support: Nil; Conflict of interest: None declared 11 International Journal of Fiber and Textile Research 2014; 4(1): 5-11
© Copyright 2024 ExpyDoc