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Aircraft manufacturing involves the drilling of a large number of holes for structural joints. The life and proper functioning of the joint can be critically affected by the quality of the hole which generally deteriorates with drill wear. In the use of composite material for the aircraft structure, the “lamination frequency,” associated with the laminated fiber of the material, can be considered to represent the waviness of the hole surface (an aspect of hole quality). The variance associated with this frequency, present in the dynamic nature of the drilling thrust and the hole surface profile, was found to change with the use of the drill. This study presents the possibility of using this change in the lamination frequency content of the drilling thrust for on-line monitoring of the drill condition, through analysis by the Dynamic Data System (DDS) technique.

A design is presented for a multilingual interactive input/output device for Indian languages. A keyboard is proposed which is based on the basic letter sounds of the Indian languages. Since the union of the sets of basic letter sounds for the major Indian languages contains about 76 sounds, a keyboard of reasonable size can be constructed which will be suitable for use throughout India. The basic letter sounds also provide a means for an unambiguous internal encoding which preserves the lexicographic order of the characters in the language(s) being used. A possible model is given for an output device that transforms the basic letter sound oriented internal representation of the characters into graphical symbols for human reading. The use of the basic letter sound representation allows a unified design which is adaptable to different regional needs.

Obtaining a straight cutting edge in the case of small twist drills warrants an accurate grinding of the “primary” flute. A transformed mathematical model which would yield the proper flute-grinding wheel profile for a straight cutting edge is developed from an existing orthogonal flute model. Also discussed in this paper is a mathematical model that describes the wheel profile for the “secondary” (non-cutting edge) flute as a function of parameters such as land width, web thickness and chip removal capacity of the drill. The model enables an analysis of the effects of improper wheel setting and point grinding on the straightness of the cutting edge. From this analysis, an optimum wheel profile that would grind a maximum number of acceptable flutes can be obtained.

Backward error recovery or rollback recovery is a well-known technique used in the design of reliable uni-processor computer systems. However, use of this technique for design of reliable distributed computer systems could result in uncontrolled rollback which is known as the domino effect. Here, we formally present the reasons for the domino effect by specifically identifying the unmatched receives (backward dependency) and unmatched sends (retransmission dependency) that occur during reexecution as the sole causes. A technique is developed which selectively stores the received messages in order to account for the backward dependencies and which coordinates the checkpoints to eliminate the retransmission dependencies, thus achieving domino-free rollback. Rollback is confined only to the interacting processes by dependency tracking of the messages. Further, we present a scheme for identifying and purging possibly contaminated messages during recovery. Our scheme is compared with some of the existing schemes and its significant advantages are highlighted.

Application of ABL, Alternative Based Language, to modelling office information systems is described. This language is powerful for the description of parallelisms and is amenable to stepwise refinement. After studying the different OIS modelling tools, we propose eight requirements of a good modelling tool and examine how well ABL fulfills these requirements. Some capabilities of the ABL environment and user interface are demonstrated. We present the ABL description of an order processing office.

Experimental methods are described for measuring the azimuthal intensity distribution of the 040 meridional reflection from cellulose fibers. The recording of the profile has been carried out with a tilted fiber diffractometer. Methods are given for correcting the recorded profile for the effect of other contaminating reflections which happen to be at nearly the same Bragg angle. The results so obtained for ramie and a number of cottons are compared quantitatively with the azimuthal profiles of the 002 equatorial diffraction from these fibers by making use of the Kratky formula. It is shown that the details of the spiral structure of cotton are more clearly brought out in the 040 profile than in that of the 002 reflection. The Kratky formula does not appear to hold good for cottons. It is shown that the usual practice of estimating the degree of orientation of the b-axis of crystallites from equatorial profiles can give rise to misleading results.

The laboratory tests which are now in use for assessing the weavability of sized warp yarns are reviewed. Reference is made to the "dummy loom" type of test in which the elements of abrasion, flexure, and cyclic loading are combined. Some data are presented on the tensile properties of sized yarns before and after they have been subjected to sus tained abrasion in the dummy loom. A study of these properties for different amounts of sixe pickup and different extents of abrasion has confirmed the hypothesis that the effect of this type of abrasion is to remove the size film at varying rates from different parts of the yarn. Some data are presented which suggest that the transient abrasive action of actual looms on sized warp yarns is similar in kind though much less severe in degree.

The Rayleigh-Gans theory of light scattering by a homogeneous cylinder has been applied to the case of scattering by a pad of fibers immersed in a liquid. The theory enables one to locate precisely the matching wavelength at which the mean refractive index of a sample of optically heterogeneous fibers coincides with that of an immersion medium. Thereby it offers a method of determining the mean refractive index. Besides, it facilitates a quantitative estimation of the variability of refractive index. The new technique has been used to study the birefringence of untreated cotton and ramie. The results are presented and discussed.

In the field of polymer physics, X-ray diffraction line profile analysis methods have yet to acquire the significance which they possess in the analysis of the fine structure of metals and alloys. The present paper attempts to put these methods on a solid theoretical basis and to introduce new concepts in the analysis of polymeric X-ray diffraction profiles. The theory of paracrystals has been used to calculate the expressions for integral line breadth and variance–range function of 0k0 diffraction profiles. The methodology is illustrated by an application of the integral breadth and variance methods to a polynosic viscose fibre, Tufcel, whose axial structure has been shown to be `paracrystalline'. Special emphasis is laid on the elimination of diffuse background scatter, the correction of profiles for angular variation factors, the problem of overlapping reflexions etc. and the superiority of the variance method over the integral breadth method in the analysis of polymeric X-ray diffraction profiles is established.

Crystallinity and crystallite size determinations have been carried out on a number of samples of swollen, hydrolyzed, and swollen and hydrolyzed cotton fibers, employing x-ray diffraction techniques and a Geiger counter recording spectrometer. A new hi variate analysis technique has been developed in order to determine the crystalline con tent of samples in which two crystalline phases are present, namely cellulose I and II. In the determination of crystallite dimensions the tilted fiber technique has been adopted for measuring crystallite lengths. A new method of resolving superposed line profiles for the measurement of crystallite width has also been developed. The results of these studies seem to suggest that there is a very close relationship between crystallinity and crystallite volume for all the types of chemical treatment studied, and that increasing crystallinity is a measure of increasing crystallite volume. On the other hand, no unique relationship between crystallinity and any one crystallite dimension has emerged for all the treatments studied. However, there are relationships which are specific to different kinds of chemical treatment of cotton.

It is pointed out that the change in refractive index with temperature of a crystal is different from what is calculated from the accompanying change in volume and the piezo-optic coefficients. The difference, which is a pure temperature effect, is explained as being due to the change in polarizability of the atoms produced by a change in the amplitude of vibration. The polarizability (α) can be expanded as a Taylor series in the changes of the distance (r) between the atoms and it is found that while the piezo-optic coefficient depends only on ∂α/∂r, the pure temperature effect is a function of ∂ 2 a/∂r 2. Making use of the experimental data, the values of a and its first two derivatives can be determined. These values are foundto be of the same order as those deduced from the intensities of Rayleigh and Raman scattering of light. The theory predicts that dn/dT should vary as the coefficient of cubical expansion at different temperatures and this is verified to be true. Finally, calculations are made of the thermo- and piezo-optic coefficients, considering the electrostatic interaction between the atoms. These do not adequately explain the observed facts, since no provision is made for the distortion of electron atmospheres around the atoms and the consequent changes in polarizability.

Letters to the Editor are brief communications intended to provide prompt publication of significant research results and to permit an exchange of views on papers previously published in the Journal. Letters are subject to review, but the authors assume full responsibility for information or opinion expressed

Interferometric studies have been made on cotton fibers as well as on twisted nylon filaments. The results so obtained provide strong evidence that the fibrils in the cotton fiber become less inclined to the fiber axis as one proceeds from the surface to the core. Also, studies on twisted nylon filaments by the fiber refractometer and Becke line techniques indicate that the latter, as practiced in this laboratory, does give values of refractive index which are heavily weighted towards the fiber periphery.

The temperature coefficient of refraction of magnesium oxide has been determined from room temperature to 400°C. at three wave-lengths, λ 4358, λ 5461 and λ 5893. The coefficients are found to be positive, as is to be expected from photo-elastic data. The values are discussed in the light of a dispersion formula for magnesium oxide newly proposed by the author, and are used to calculate the temperature shift of the effective characteristic frequency of the crystal in the ultra-violet.

Small angle scattering patterns have been photographed from cotton (and viscose) fibres containing deposits of silver, mercuric sulphide, lead sulphide, lead chromate and lead iodide. These patterns have shown that deposits of the cubic crystals are nearly isodiametric and randomly oriented. On the other hand, particles of lead chromate and lead iodide are elongated, with the longer direction tending to be oriented along the fibre axis. These conclusions are in agreement with evidence on orientation secured from wide-angle diffraction. In the case of the randomly oriented deposits, extensive measurements have been made of the angular dependence of equatorial scattered intensity. Distributions of particle size have been computed which will synthesize back the scattered intensity. Some limitations of such calculations have been pointed out. It has been concluded, however, that the majority of particles are crystallites with dimensions of 200 A or less. There are a few particles with very much larger dimensions. These may be polycrystalline aggregates which are lodged in the fibre lumen rather than in cellulosic substance.

Bundles of cotton fibers have been mercerized at various controlled stretches. The x-ray orientation factor, static elastic modulus, and load-extension behavior of these fibers have been determined. The effect. of changes in fine structure on changes in mechanical properties is discussed in terms of the above data.

X-ray methods have been used to measure crystallinity and crystallite dimensions in cotton fibers that have been swollen in aqueous solutions of caustic soda, ethylene diamine, and zinc chloride. Different times, temperatures and concentrations of swelling agent have been used. Optimal decrystallizing conditions are given, together with re sidual crystallinities and crystallite sizes. The inter-relation between crystallinity and crystallite size is discussed.

A theoretical study of a method based on the “compound resonance” principle for the measurement of the dynamic Young's modulus of short staple fibers is presented. The system considered is a fixed-free cantilever spring coupled at the free end to the fiber. Representing the fiber as a Voigt element and neglecting the losses in the cantilever spring, it is shown that both the real and imaginary parts of the dynamic modulus of the fiber can be calculated from the amplitude or velocity response of the system to forced vibrations in the neighborhood of resonance.

A simple theoretical formulation is developed whereby it is possible to predict the load-extension behavior of an ideal bundle of textile strands in terms of the behavior of the components. Further, it is shown that the same theory can be applied in reverse to extract from the load-extension curves of the bundle the following tensile properties of single strands: (a) the extensibility distribution (b) the average breaking strength. The theory has been applied to single strands and cut skeins of cotton and viscose staple fiber yarns and is shown to be very successful in these cases.

This paper presents x-ray diffraction studies on acid-hydrolyzed and ball-milled celluloses which are, respectively, used as "standards" of crystalline and amorphous cellu lose in crystallinity determinations of other samples. It is shown that the observed x-ray powder diffractograms of cellulose I and II standards, when compared with calcu lated diffraction profiles of cellulose crystallites with certain plausible dimensions, clearly indicate the presence of small amounts of imperfectly ordered material in both "standards." Data on some physical properties of these standards also support this finding. In the case of ball-milled cellulose, it has been shown that above a scattering angle of 43° with copper radiation, the intensity of scattering can be completely accounted for in terms of independent scattering from individual β-anhydroglucosidic units. Below this angle, the diffuse maximum in the scattering curve appears to be due to the repeat distance within a cellulose chain. Thus, ball-milled cellulose is a satisfactory amorphous standard.

Cultivated groundnut or peanut (Arachis hypogaea L.), an allotetraploid (2n = 4x = 40), is a self pollinated and widely grown crop in the semi-arid regions of the world. Improvement of drought tolerance is an important area of research for groundnut breeding programmes. Therefore, for the identification of candidate QTLs for drought tolerance, a comprehensive and refined genetic map containing 191 SSR loci based on a single mapping population (TAG 24 × ICGV 86031), segregating for drought and surrogate traits was developed. Genotyping data and phenotyping data collected for more than ten drought related traits in 2–3 seasons were analyzed in detail for identification of main effect QTLs (M-QTLs) and epistatic QTLs (E-QTLs) using QTL Cartographer, QTLNetwork and Genotype Matrix Mapping (GMM) programmes. A total of 105 M-QTLs with 3.48–33.36% phenotypic variation explained (PVE) were identified using QTL Cartographer, while only 65 M-QTLs with 1.3–15.01% PVE were identified using QTLNetwork. A total of 53 M-QTLs were such which were identified using both programmes. On the other hand, GMM identified 186 (8.54–44.72% PVE) and 63 (7.11–21.13% PVE), three and two loci interactions, whereas only 8 E-QTL interactions with 1.7–8.34% PVE were identified through QTLNetwork. Interestingly a number of co-localized QTLs controlling 2–9 traits were also identified. The identification of few major, many minor M-QTLs and QTL × QTL interactions during the present study confirmed the complex and quantitative nature of drought tolerance in groundnut. This study suggests deployment of modern approaches like marker-assisted recurrent selection or genomic selection instead of marker-assisted backcrossing approach for breeding for drought tolerance in groundnut. Electronic supplementary material The online version of this article (doi:10.1007/s00122-010-1517-0) contains supplementary material, which is available to authorized users.

Key message Successful introgression of a major QTL for rust resistance, through marker-assisted backcrossing, in three popular Indian peanut cultivars generated several promising introgression lines with enhanced rust resistance and higher yield. Abstract Leaf rust, caused by Puccinia arachidis Speg, is one of the major devastating diseases in peanut (Arachis hypogaea L.). One QTL region on linkage group AhXV explaining upto 82.62 % phenotypic variation for rust resistance was validated and introgressed from cultivar ‘GPBD 4’ into three rust susceptible varieties (‘ICGV 91114’, ‘JL 24’ and ‘TAG 24’) through marker-assisted backcrossing (MABC). The MABC approach employed a total of four markers including one dominant (IPAHM103) and three co-dominant (GM2079, GM1536, GM2301) markers present in the QTL region. After 2–3 backcrosses and selfing, 200 introgression lines (ILs) were developed from all the three crosses. Field evaluation identified 81 ILs with improved rust resistance. Those ILs had significantly increased pod yields (56–96 %) in infested environments compared to the susceptible parents. Screening of selected 43 promising ILs with 13 markers present on linkage group AhXV showed introgression of the target QTL region from the resistant parent in 11 ILs. Multi-location field evaluation of these ILs should lead to the release of improved varieties. The linked markers may be used in improving rust resistance in peanut breeding programmes. Electronic supplementary material The online version of this article (doi:10.1007/s00122-014-2338-3) contains supplementary material, which is available to authorized users.

A simple mathematical model was derived to predict tensile properties of single cotton fibers from bundle load-elongation curves. The average breaking extension, coefficient of variation of breaking extension, and the average breaking strength were obtained. The validity of the model was verified on two samples of cotton.

Twenty five young patients were studied by M-mode echocardiography from the suprasternal notch. The findings were compared with the angiographic findings. Good visualisation of the aorta, and right pulmonary artery was obtained in all patients by suprasternal echocardiography. while the left atrium was well visualised in twenty patients. Strong correlation was found between the ultrasonic and angiographic lumen measurements of the aorta, right pulmonary artery and the left atrium in the superoinferior axis. We conclude that suprasternal M-mode echocardiography is a useful and reliable noninvasive method of studying the great vessels and the left atrium.

The temperature coefficients of refraction of lithium fluoride, fluorspar, magnesia and quartz have been determined interferometrically for wavelengths betweenλ 2500 andλ 6000, from room temperature to 400°C. The values have been utilised, in conjunction with dispersion formulae mostly proposed by the author, to calculate the temperature dependence of the ultra-violet frequencies, using Ramachandran’s theory of thermo-optic behaviour. The theory is found to account successfully for the variation ofdn/dt with wavelength and temperature. Similar results have been obtained in the visible region alone for the three refractive indices of barite.

Dispersion formulae valid in the visible region are offered for rutile, anatase and brookite. These incorporate a characteristic frequency at 2870 A in all the cases. The value ofdn/dt in the three crystals are explained by large transfers of transition probability and moderate shifts towards large wave-lengths of this frequency as the temperature is raised. In addition, a calculation is made of the refractive indices and birefringence of rutile on the basis of Bragg’s theory and the results are in good accord with the observed data.

Dispersion formulae of the Drude form have been worked out using the latest data on dispersion and absorption for all the alkali halides for which measurements are available and for which no formulae have been proposed so far.

We report the preparation of CdS nanorods using a thiosemicarbazide complex of cadmium [Cd(NH2CSNHNH2)2Cl2]. The precursor was decomposed in tri-n-octylphosphine oxide (TOPO) at 280 degrees C to give TOPO capped CdS nanoparticles; nano-dimensional rods of the material are clearly visible in transmission electron microscopy (TEM); the particles have been further characterised by X-ray diffraction (XRD) and selected area electron diffraction (SAED) and optical measurements.