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Recent research focused on novel aspects of sulphur and sulphur-containing molecules in fundamental plant processes has highlighted the importance of these compounds. Currently, the focus has shifted to the efficacy of hydrogen sulphide (H

Purpose Most researchers have neglected the effect air-drag force on yarn tension during rotor spinning. This paper aims to study the effect of rotor air-vacuum pressure in conjunction with opening roller speed and yarn linear density on the yarn tension generated during the rotor spinning, which has established their significant influences on both the mean and the peak tension.This is the first of one-of-a-kind experimental study being reported to demonstrate the influence of air-drag force on yarn tension during the rotor spinning under dynamic condition. Design/methodology/approach The dynamic measurements on yarn tension at the exit of the doffing tube were carried out by using an electronic capacitive yarn tension meter during rotor spinning. The derived experimental data were fitted into equations to construct the response equations and to work out the coefficients of multiple correlation between the data and the predicted equation for both the mean and the peak tension. Various surface plots were constructed by using those response surface equations, so as to study the effect of variables on yarn tension generated during the rotor spinning. Findings The study has established that the rotor vacuum is responsible in causing a change in yarn tension, it increases with the decrease in air-vacuum inside the rotor. The involvement of the opening roller speed in altering yarn tension during rotor spinning has been proved. As the opening roller speed changes, so does the air stream surrounding the opening roller speed with consequent alteration of the centrifugal force generated due to the rotation of the rotor. The centrifugal force and, hence, the yarn tension generated in the rotor will be simultaneously affected by both the rotor relative vacuum and the opening roller speed. Research limitations/implications This is a structured experimental study to verify the influence of air-drag force generated during rotor spinning on yarn tension. Very limited theoretical work has been carried out in this direction as reported in the introductory part of the paper. The result of the present study will encourage future researchers to revisit the theory on generation of air-drag force during rotor spinning and work out a new formula. Practical implications Next only to the conventional ring spinning system, the rotor spinning holds the second place in the share of global yarn production. Because of its advantage of lower cost of production and amenability to automation, the rotor spinning has gained acceptance in spun yarn production, particularly for spinning coarse and medium counts of yarns. Currently, it has acquired about 25 per cent share in the world’s spun yarn production. As many of the rotor machine variables significantly affect fibre configurations and, subsequently, the yarn properties by influencing the airflow characteristics inside the rotor unit, the study of yarn tension during rotor spinning and its analysis assumes a significance. Social implications Rotor spinning is a relatively new and faster method of conversion of discrete fibres into continuous staple yarn and, subsequently, various textiles and garments. Its yarn is distinct and a bit different compared to the conventional ring yarn. It has got wide acceptance in the market and fashion. As such, the spinning sector that converts fibres into yarns is an important industry world over, providing employment to many. Besides, being the basic operation in the fibre value chain, it supports many downstream activities, including human clothing and fashion. Thus, the research on rotor spinning, particularly the yarn engineering to produce better products will be helpful to strengthen and grow the textile value chain. Originality/value This is an original research study. The magnitude and the direction of the air drag on the yarn during rotor spinning is very difficult to assess. Thus, most researchers for the sake of simplicity in analysis have neglected its effect on yarn dynamics, but a few of them have taken note of it in their theoretical propositions. However, no experimental result has been reported so far in the literature, supporting the influence of such air-drag force on yarn tension in the rotor spinning. In fact, none of the above studies have considered the induced effect of centrifugal force caused because of the rotation of the opening roller on the airstream that flows from the transfer channel inlet into the rotor because of its partial vacuum, causing consequential effects on air-drag force and tension in the yarn inside the rotating rotor. This is the first of one-of-a-kind experimental study being reported to demonstrate the influence of air-drag force on yarn tension during the rotor spinning under dynamic condition.

In rotor spinning, it is generally regarded that the maximum fibre length (LFibre) should not exceed the rotor diameter (Drotor), and as such, their ratio (LFibre/Drotor) should lie between 0.5 and 1 for the proper processing and yarn formation to ensure production of an acceptable quality of the yarn. The present study examines the validity of the said guideline in terms of mean and peak yarn tensions generated during the spinning and their correspondence with the yarn quality. The study found that the optimum yarn quality can be produced, if LFibre/Drotor ≈ 0.8, at which the mean yarn tension maximizes and the peak yarn tension minimizes.

Coated and laminated textiles are built as durable and high-performance products. Coatings are designed to adhere inseparably to their substrates and lamination adhesives are supposed to have long-term bonding properties, therefore, they are difficult to disassemble and reuse. Further, increasing the use of nanomaterials in coating adds complexity to recycling and waste management. However, in sync with the general demand that today’s industrial production must adopt a circular economy for sustainability and endeavor reduction of the earth’s pollution load with which its inhabitants are constantly endangered, coating industry is welcoming and adopting various practices for waste control, reuse, and recycling of both in-house materials and used products before disposal. In this direction, the present chapter reviews the status of waste minimization, choosing the right raw materials and making the most out of them by incorporating efficient processes, as well the concept of reuse and recycling of the discards. If cradle to cradle approach in reuse and recycling is adopted by the coating and the laminating industries properly, it will solve the problems of their garbage, and the associated environmental pollution.

1,2- and 2,1-benzothiazines, for example, 1,2-benzothiazine-1,1-dioxides. 2,benzothiazine-2,2-dioxides, 1-alkyl/aryl-1,2-/2,1-benzothiazine-S-oxides, dibenzothiazine and polyheterocycle containing ...

Purpose Dref-3 friction spun core yarns produced using staple fibre yarn as the core, e.g. Jute core yarn wrapped with cotton fibre, have poorer mechanical properties compared to the core yarn itself. The purpose of this study was to understand the structure of such yarns, that will lead to the optimization of fibre, machine and process variables for production of better quality yarn from the Dref-3/3000 machines. Design/methodology/approach The Dref spinning trials were conducted following a full factorial design with six variables, all with two operative levels. The Dref-3 friction spun yarn, in which the core is a plied, twisted ring yarn composed of cotton singles and the sheath, formed from the same cotton fibres making the singles, has been examined. The structures have also been studied by using the tracer fibre technique. Findings It was observed that rather than depending on the plied core yarn, the tensile properties of the Dref-3 yarn are significantly determined by the parameters those affect the constituent single yarn tensile properties, i.e. the amount of twist and its twist direction, yarn linear density and the sheath fibre proportion used during the Dref spinning in making the final yarn. Further, when the twist direction of single yarn, double yarn and the Dref spinning false twisting are in the same direction, the produced core-sheath yarn exhibits better tensile properties. Practical implications The understanding of the yarn structure will lead to optimized production of all staple fibre core Dref spun yarns. Social implications The research work may lead to utilization of coarse and harsh untapped natural fibres to the production of value-added textile products. Originality/value Though an earlier research has reported the effects of sheath fibre fineness and length on the tensile and bending properties of Dref-3 friction yarn, the present study is the first documented attempt using the tracer fibre technique to understand Dref-3 yarn structure with plied staple fibrous core.

An alkali based method has been optimised and proposed to extract the cellulosic fibres from the corn husks. Physicochemical and morphological properties of the fibres extracted from corn husk have been studied in detail, and compared with the well-explored cellulosic fibre, like cotton and ligno-cellulosic fibre, like jute. Scanning electron microscopy and energy dispersive X-ray were used to study the surface and cross-sectional morphology and the elemental analysis of the corn-husk fibres and compared with cotton and jute fibres. The analysis showed that the morphological and the physico-chemical properties of the extracted corn husk fibres are comparable with ligno-cellulosic jute fibre. Also, improvement in thermal stability of corn husk fibre was obtained by application of the agro-waste banana pseudostem sap (BPS). BPS treated corn husk fibre showed the limiting oxygen index (LOI) value of 32 against the LOI value of 21 for the control corn fibre. In vertical burning test BPS treated corn yarn showed self extinguishing behaviour and 50 mm char length whereas control corn yarn was burnt within 1 min with flame and afterglow. TG analysis of the BPS treated corn yarn showed more than 30% weight retention at 450 °C compared to the 20% weight retention of the control corn yarn at the said temperature. In addition, major mass loss peak in TG curve has been shifted from 350 to 300 °C after BPS treatment (signature of the dehydration effect of the treated corn yarn). The flame retardant treatment process is comparatively simple and cost-effective, as add-on remains only at 8% and the BPS is available in large quantity in many countries.

This article discusses the structure–property relationship of DREF-3 friction spun cotton yarn in which the core is a single twisted cotton ring yarn and the sheath is made of the same cott...

This research involves the optimization of different variables of the operating conditions to prepare activated carbon from pomegranate peels (Punica granatum peel). For this purpose, a statistical method called Response Surface Methodology (RSM) has been adopted to economize the number of experiments and their meaningful interpretation. Activated carbon was produced by chemical activation (H3PO4). RSM was used to evaluate the variables considered in the preparation of activated carbon such as impregnation ratio (2–4 g H3PO4/g pomegranate peel), temperature (400–600°C), and activation time (30–90 min), experimented using a three-variable Box–Behnken Design (BBD) based on a quadratic model and an RSM tool provided by Design Expert 8.0.4 (STAT-EASE Inc., Minneapolis, USA). The responses analyzed for optimization were the methylene blue number and the iodine number. The factors that are significant influencing the activated carbon preparation have been identified by an analysis of variance (ANOVA). The optim...

While assessing the overall yarn tension in rotor spinning, most of the researchers have ignored the contribution of peeling-off tension (T0) assuming this being small. However, experiments in the present study showed a significant discrepancy between the calculated and the measured mean yarn tension due to neglect of T0. Further, T0 has a bearing in twist propagation and compacting the fibres in the zone of Peripheral Twist Extent (PTE) for ensuring continuity of the yarn formation. In the present study, a theoretical deduction has been made to estimate T0 by summing up the contributions due to fibre tension at the yarn formation point and the tension arising out of the length of the PTE sliding in the rotor groove. The dependence of T0 on various rotor and fibre variables has also been established.

The flame retardant functionality was imparted in cellulosic textile using banana pseudostem sap, an eco-friendly waste plant product. The extracted sap was applied in three different pH conditions, viz. acidic, neutral and alkaline to the pre-mordanted bleached and mercerized cotton fabrics. Flame retardant characteristics of both the control and the treated fabrics were analysed in terms of limiting oxygen index, vertical flammability and heat release related properties using a cone calorimeter. The thermal degradation and pyrolysis mechanism were studied using thermogravimetric analysis and differential scanning calorimetry. The elemental analysis was carried out with X-ray fluorescence, and the quantification of phosphorus and nitrogen was also done. Besides, the charring mechanism of both the control and the treated fabric was analysed in detail, and a char structure model has been proposed. The treated fabrics were also evaluated in terms of colour and other physical properties.

Nylon-6,6 fabric was treated with formic acid for surface roughening and was subjected to Resorcinol Formaldehyde Latex treatment for making rubber composites. Physicochemical effects of surface roughening of nylon were evidenced using scanning electron microscope (SEM), Fourier Transform Infrared spectroscope (FTIR) and differential scanning calorimeter (DSC). Further, the treatment effect on interfacial adhesion was quantified through peel strength test. The process parameters of the formic acid treatment were optimized using Box-Behnken method through geometrical surface roughness obtained through Kawabata evaluation system for micro-surface roughness of nylon to ensure good interfacial adhesion with rubber. Surface modification conditions of 11.2% formic acid concentration, 70 °C temperature and 30 min time were found to yield optimum condition at which surface roughness (SMD) was found to be of 20.1 μm. SEM analysis confirmed the presence of heterogeneous appearance like cracks, etches and mi...

Sagdeev potential approach is used for the study of nonlinear propagation of ion-acoustic waves in plasma consisting of cold positive ions and nonthermal electrons. The nonlinear equation so derived are analysed with the help of Bogoliubov–Mitropolosky method. The profiles of Sagdeev potential solitary waves are evaluated in first-, second- and third- order which are depicted for different values of nonthermal parameter of electrons. It is seen that nonthermal electrons has considerable impact on the shape of ion-acoustic solitary waves in each order. The plasma consisting of cold positive ions and no negative ions can support the formation of compressive as well as W-type solitary waves in second- and third- order for certain value of nonthermal parameter of electrons. The results are new because W-type ion-acoustic solitary wave is found by earlier authors in plasma in presence of negative ions only. The ion-acoustic solitary waves near critical value of nonthermal parameter and arbitrary amplitude solitary waves in presence of nonthermal electrons have also been studied in the paper. Moreover, the solution for ion-acoustic double layers in plasma consisting of nonthermal electrons is obtained. Our results in the paper would be useful to understand the nonlinear wave processes in ionospheric and magnetospheric multicomponent plasma having nonthermal electrons.

Flame retardancy was imparted to a scoured and bleached, proteinous woollen textile by using banana pseudostem sap, an ecofriendly waste agricultural product, at different pH levels. The flame retardancy characteristics of both the control and the treated fabrics were analysed in terms of the limiting oxygen index and the vertical flammability measurement. Thermal degradation and fire retardancy mechanisms were studied using thermogravimetry, scanning electron microscopy, and energy dispersive X-ray analysis. Moreover, the charring mechanism of both the control and the banana-pseudostem-sap-treated fabrics with varying pH was analysed and reported in detail. The wool fabric was also dyed with CI Acid Blue 25 using banana pseudostem sap as well as water as the medium. The fabric dyed with the banana pseudostem sap medium at pH 5.5 showed more colour exhaustion, colour strength, and thermal stability compared with the control wool fabric. The mechanism by which superior fire retardancy and colour strength are imparted to the woollen textile by the application of banana pseudostem sap is proposed.

A low cost composite material was prepared by using waste newspaper and polyester resin. The waste newspaper used in the study was characterized by chemical and X-ray diffraction (XRD) methods, and tensile strength was measured. Waste newspaper contains holocellulose of about 83.2% and the crystallinity index of the newspaper is 64.2. Composite samples were fabricated with three different fibre contents, namely 25%, 33%, and 48% (by weight). It was observed that on increasing the fibre content from 25% to 48%, the tensile strength and the modulus also increased by 54%–40%, respectively, along the fibre direction. It was observed that with 48% (w/w) fibre content, the waste paper composite yielded 70 MPa tensile strength and 6 GPa modulus in the fibre direction and 19 MPa tensile strength and 2.41 GPa modulus in the cross direction. The newspaper composite samples were characterized by thermogravimetric analysis, Fourier transform infrared spectroscopy (FTIR) and scanning electron microscopy (SEM) analysis.

Fire resisting property was imparted to cellulosic paper by the application of a bio-enriched version of a banana pseudostem sap (BPS) as well as the only BPS, obtained as a byproduct during fibre extraction from the pseudostem. The papers were evaluated for their flame retardant property by measurement of limiting oxygen index and vertical flammability. They were also characterized by thermogravimetry, scanning electron microscopy and energy dispersive X-ray analysis. The bio-enriched BPS treated paper was found to exhibit a better flame retardancy with distinguished char length, compared to the control and the only BPS treated paper. The impartment of flame resisting property to a paper by the BPS, along with its charring behaviour has been discussed and the mechanism thereon has been postulated. The BPS application was found to enhance the oxygen required for the burning of the paper and reduce its burning rate by promoting more dehydration and char formation. The imparted fire retardant finish found durable to weathering, did not cause any significant loss in tear and tensile properties of the paper.

Purpose – The purpose of this paper is to use the natural wastage plant product, bannana pseudostem sap (BPS) for using as fire retardant of cellulosic textile substrate. The study aims to use first time any wastage plant product for making fire retardant cellulosic textile. In this regard flame retardant functionality was imparted in cellulosic textile using BPS, an eco-friendly natural wastage product. Design/methodology/approach – The extracted sap was made alkaline and applied in pre-mordanted bleached and mercerized cotton fabrics. Flame retardant properties of the control and treated fabrics were analyzed in terms of limiting oxygen index (LOI), horizontal and vertical flammability and total heat of combustion using bomb calorimeter. The thermal degradation and pyrolysis was studied using thermogravimetric analysis (TGA). The chemical composition of the control and BPS treated cellulosic fabric were analyzed by FTIR, SEM and EDX. Durability of the flame retardant functionality to soap washing had also been studied. Findings – The study showed that the treated fabrics had good flame retardant property compared to control fabrics. The LOI value was found to increase by 1.6 times after application of BPS. As a result of this, the fabric does not catch flame. In horizontal flammability, the treated fabric showed burning with afterglow (without presence of flame) with a propagation rate of 7.5 mm/min, which is almost ten times lower than the control fabric. After application of BPS cellulosic fabric sample produced natural khaki colour. There was no significant change in other physical properties. Practical implications – The application process is simple and cost-effective as no costly chemicals were used. Further advantage is that the treated fabric could also be considered as natural dyed cotton fabric. The developed khaki colour is quite attractive and stable to sun light exposure. This developed process could used in colouration and flame retardant finishing of home furnishing products such as home-window curtain, railway curtain, hospital curtain, table lamp and as a covering material of non-permanent structure like in book fair, festival, religious purpose, etc., where large quantity of textile is used and has chance of fire hazards. Social implications – BPS abundantly available in Indian as well as other countries and it is normally considered as waste material. It is eco-friendly and produced from renewable source. Therefore, the application of BPS in cotton textile for colouration and functionalization will give the advantages of value addition using natural product. Rural people will be benifited lot by applying this technology whenever it required. Originality/value – This paper helps to clarify first time why and how a wastage plant product like BPS can be used for preparing fire retardant cotton cellulosic fabric.

Flame retardancy was imparted in cellulosic cotton textile using banana pseudostem sap (BPS), an eco-friendly natural product. The extracted sap was made alkaline and applied in pre-mordanted bleached and mercerized cotton fabrics. Flame retardant properties of both the control and the treated fabrics were analysed in terms of limiting oxygen index (LOI), horizontal and vertical flammability. Fabrics treated with the non-diluted BPS were found to have good flame retardant property with LOI of 30 compared to the control fabric with LOI of 18, i.e., an increase of 1.6 times. In the vertical flammability test, the BPS treated fabric showed flame for a few seconds and then, got extinguished. In the horizontal flammability test, the treated fabric showed no flame, but was burning only with an afterglow with a propagation rate of 7.5 mm/min, which was almost 10 times lower than that noted with the control fabric. The thermal degradation and the pyrolysis of the fabric samples were studied using a thermogravimetric analysis (TGA), and the chemical composition by FTIR, SEM and EDX, besides the pure BPS being characterized by EDX and mass spectroscopy. The fabric after the treatment was found to produce stable natural khaki colour, and there was no significant degradation in mechanical strengths. Based on the results, the mechanism of imparting flame retardancy to cellulosic textile and the formation of natural colour on it using the proposed BPS treatment have been postulated.

Flame retardant functionality was imparted in cellulosic textile using spinach leaves juice (SJ), an eco-friendly natural product. The extracted juice was made alkaline and applied in fresh bleached and mercerized cotton fabrics. Flame retardant properties of the control and treated fabrics were analysed in terms of limiting oxygen index (LOI), horizontal and vertical flammability and radiant heat testing. The study showed that the treated fabrics had good flame retardant property compared to control fabrics. The LOI value was found to increase by 1.6 times after application of SJ. As a result of this, the fabric does not catch flame. In horizontal flammability, the treated fabric showed burning with afterglow (without presence of flame) with a propagation rate of 10 mm/min, which is almost nine times lower than the control fabric. The thermal degradation and pyrolysis was studied using thermogravimetric analysis. The chemical composition of the control and SJ-treated cellulosic fabric were analysed by FT...

In this study, the moisture and thermal transmission properties of cotton/polylactic acid-blended knitted fabrics were studied. Cotton and polylactic acid fibers were blended to produce yarns of 14.7 tex (40 s Ne) with two different blend proportions. The yarns were then knitted into plain jersey structures, followed by scouring and bleaching treatments. The produced fabrics were evaluated for dynamic moisture transport properties using SDL Atlas moisture management tester. The moisture vapor transmission rate of developed fabrics was measured using the dish method, and the thermal properties were measured using KES Thermolabo instrument. Results indicate that blending of polylactic acid fibers with cotton fibers improve the moisture management properties of the resultant fabric. The overall moisture management capability values were found to be better for cotton/polylactic acid fiber 65:35 blended fabric. A marginal improvement was observed only in the case of cotton/polylactic acid fiber 80:20 blended fabric. The moisture vapor transmission and air permeability of blended fabrics were also found to be higher than those of 100% cotton fabric. The thermal conductivity, insulation, and warm–cool feel values of blended fabrics range between 100% cotton and 100% polylactic acid fiber fabrics. This type of fabric is more suitable for use as sportswear and active wear.

The mechanical properties of both brown and green coconut husk were evaluated by using Universal Testing Machine (UTM). Different auxiliary tools were employed for gripping and mounting the peculiar shaped coconut husk on to the machine. Tensile and compression test (both in longitudinal and transverse direction), tear strength, and U-bend test of the husk were carried out. Husk offered maximum resistance in longitudinal direction of tensile load and in the transverse direction for compression load. Husk disintegration is easy in longitudinal direction. The green husk was found stable to deformation and resilient as compared to brown husk, thus needing less beating force for fiber disintegration.

Flame retardant and antimicrobial functionalities were imparted in jute textile using sodium metasilicate nonahydrate (SMSN), commonly known as “water glass”. Sodium metasilicate nonahydrate (SMSN) was applied in jute fabric in different concentration by padding method followed by drying. Flame retardancy of the fabric was evaluated by Limiting Oxygen Index (LOI) and burning behaviour under vertical flammability tester including the char length. Burning rate was found to decrease by almost 10 times after an application of 2% SMSN compared to the control sample. Thermogravimetry (TG) and differential scanning calorimetry (DSC) analysis of both the control and treated jute fabrics were utilized to understand the mechanism of developed flame retardance in jute fabric. It was observed that the SMSN treated samples showed excellent antimicrobial property against both gram positive and gram negative bacteria. Antimicrobial properties of both the control and treated jute fabrics were also measured quantitatively.

A recently developed frequency-modulated thermal wave imaging (FMTWI) has been applied for subsurface defect detection of jute fibre-reinforced polypropylene (PP) matrix composite. Composites are subject to manufacturing and in-service defects like voids, delamination, cracks and so on. Active thermography like lock-in thermography (LT) and pulsed thermography (PT) has been widely used for non-destructive testing of composites and laminates. FMTWI may be viewed as a superposed LT, wherein multiple frequency response is obtained through single measurement. It is very much suitable for newly developed material for which the thermal properties are not well established, thereby impeding the choice of appropriate frequency for conventional LT. In this article, FMTWI is applied to detect and characterize artificially generated subsurface defects in jute–PP composite. The measurements also show the effect of frequency on the depth of defect detection and accuracy.

No other apparel or garment has received such wide acceptability for so many years since its inception by so many people irrespective of age, classes, gender and status as denim trousers, popularly known as ‘blue jeans’, a 100% cotton product. With time, it has gone from being a symbol of cowboys to a common garment for all men, women, youth and well-off people. It has evolved from work wear to casual wear, and then to premium and functional wear. Denim washing industries mostly use cellulase enzyme, alone or preferably combined with pumice stone to achieve a soft handle and/or a purported worn look. However, to address issues relating to environmental concerns associated with traditional washing, apart from meeting growing market demands for denim, research has been undertaken to obtain equivalent or better quality of appearance and manufacturing conditions by adopting eco-friendly emerging processing techniques such as laser, plasma, ozone and sand-blasting. In many cases, oxygen cold plasma has been attempted to desize and fade the colour of denim. The faded effect is comparable to a suitable enzyme-treated sample. Three laser sources, namely beams from an Nd:YAG laser (1.064 μm and its second harmonic, 532 nm), a CTH:YAG laser (2.09 μm) and a CO 2 laser (10.6 μm), were explored for denim processing; of these, the CO 2 laser was found to be the most suitable and efficient for denim processing. The current chapter discusses the application of emerging water-free technologies in denim processing and technological advancements in traditional processes to make them environmentally friendly.

Wet-chemical processing of textile substrates starting from its preparatory to dyeing/printing followed by finishing is important for its value addition in terms of aesthetic value, removal of impurities, colour shade, colour pattern and requisite functionality. However, some of the traditional processes are water, energy and chemical intensive. In the recent time, due to global awareness on environmental pollution, climate change, global warming, carbon footprint and sustainability, both the academic research and industrial product development have been intensified to seek for sustainable dyeing and finishing processes, using biomacromolecules, biomaterials, plant extract, biopolymer and water-free technologies. In this context, deoxyribonucleic acid (DNA) from herring sperm, whey proteins, casein, chicken feather protein (CFP), banana pseudostem sap (BPS), spinach juice (SJ) and green coconut shell extract (GCSE) has been explored for improving the thermal stability of cellulosic, lignocellulosic and protein substrates. Similarly, agro-waste, nanolignin, silk sericin and aloe vera have been successfully extracted and applied in textile substrates to protect its user from the harmful ultraviolet (UV) rays. The above natural ingredients and a few more from marigold, manjistha, annatto, neem, turmeric, sandalwood, tulasi, jasmine, lemon, lavender and sandalwood have also been explored for natural dyeing, UV protective, aroma and antimicrobial finishing of textile. Water-less plasma and UV treatment can also be used as a pre-treatment, post-treatment, in situ reaction or post-polymerization for surface activation, oxidation, etching, polymerization, coating and deposition to impart value-added functionalities, such as water and oil absorbency, water and oil repellency, flame retardancy, UV protection, anti-static property and dyeing of various textile substrates.

Within the framework of a general equilibrium model we study the long-run dynamics of a prey-predator model in the presence of an alternative prey. Our results show that sustainability, i.e. a positive value of the population in the long run, essentially depends on individual harvesting efforts and digesting factors relative to alternative prey. A detailed bifurcation analysis evidences the richness of possible long-run dynamics. Our model clearly shows that the role of an alternative prey must be taken into consideration when studying prey-predator dynamics.

Horseradish peroxidase (hydrogen peroxide oxidoreductase [1.11.1.7]) has been cross-linked in methylene chloride using N,N'-carbonyldiimidazole to produce a water insoluble preparation which retains enzymatic activity. Relative to native enzyme, which was treated with methylene chloride but not N,N'-carbonyldiimidazole, the cross-linked product displayed significant stability toward denaturation in aqueous mixtures of ethanol, methanol, and 1,4-dioxane. The cross-linked product showed a a marked stability toward thermal denaturation relative to the native protein. Applications of the catalyst in chemical reactors for the preparation of synthetic quinones are discussed.

We investigated the electrical-transport properties of hydroiodic acid doped polyaniline in the temperature range 77–300 K, applying magnetic field strength to a maximum of 1 T in the frequency range 20 Hz–1 MHz. The direct-current conductivity was explained by variable range hopping theory, and the direct-current magnetoconductivity, which was positive, was interpreted by orbital magnetoconductivity theory. The alternating-current (ac) conductivity was found to follow the universal dielectric response σ′(f) ∝ fs, where σ′(f) is the frequency-dependent real part of the complex ac conductivity, f is the frequency, and s is the frequency exponent. The trend in the variation of s, the temperature dependence of the frequency exponent, corroborated the fact that the correlated barrier hopping was the dominating charge-transport mechanism. The ac conductivity also showed a positive variation with magnetic field, which could be interpreted by this theory. © 2008 Wiley Periodicals, Inc. J Appl Polym Sci, 2008

Fashion can be encapsulated as the prevailing styles manifested by human behaviour and the latest creations by the designers of textile and clothing, footwear, body piercing, decor, etc. Fashion can trace its history to the Middle East (i.e., Persia, Turkey, India and China). Natural fibres such as silk, wool, cotton, linen, jute and ramie (a flowering plant in the nettle family) and man-made fibres such as regenerated rayon, cellulose acetate, polyester, acrylic, bamboo, and soy protein are intensively used for the production of traditional to specialty apparel, home furnishings and interior decorative textiles. To prepare fibres for use they are enhanced during spinning, weaving, knitting and chemical processing. Linen/flax is considered the most important and useful natural fibre as far as fashion is concerned for tops, shirts and summer dresses. Recently (as of 2016), a few more protein fibres—such as angora, pashmina and yak—have also been exploited to produce luxurious fashionable textiles, owing to their exotic features. Natural fibre–based textiles are being increasingly dyed in a sustainable manner using eco-friendly natural dyes that are fixed by using bio-mordants (plants that accumulate alum in their leaves). Similarly, the potential naturally coloured cotton has for traditional to fashionable end applications is also highlighted in this chapter. As far as sustainable development is concerned, textiles are preferred to be made of natural fibres and to be value-added with eco-friendly chemicals and auxiliaries, preferably derived from natural resources such as plant/herbal extracts, bio-materials, bio-polymers and bio-molecules.

The results on the measurement of conductivity of oxalic acid doped polyaniline in the temperature range 77 ≤ T ≤ 300 K , applying magnetic field up to 1 T in the frequency range 20–1 MHz are being reported. The dc conductivity has been interpreted by variable range hopping theory. The magnetoconductivity is positive, which is well explained by orbital magnetoconductivity theory. The frequency dependence of conductivity has been described by power law and the frequency exponent ‘ s ’ is found to be decreasing with temperature. The dielectric permittivity is large, which has been interpreted by the grain and grain boundary effect. Magnetic field dependence ac conductivity shows a positive variation. A firm theoretical explanation of magnetic field dependence of ac conductivity is still lacking. The different parameters like Mott characteristic temperature and localization length were calculated from the experimental data, the values of these parameters depend strongly on the resistivity ratio.

Packaging is a, essential requirement for fruits, vegetables, agricultural crops, food products, and other commodities to provide the requisite protection from physical damage, contamination, deterioration; to increase shelf life; and facilitate need-based supply from the producer to the consumer. The packaging material should be physically and mechanically strong and should not add any foul odor to the packed product. In the past, for packaging of the above-mentioned products as well as various industrial goods has been made of traditional to advanced materials such as metal and glass; ordinary, coated, and laminated paper; corrugated paper box; gunny sack; textile bag; bamboo slit; wooden box; biodegradable film; nonbiodegradable plastic/film; composite; and nanocopmosite/biocomposite, all of which have been widely used. During the past 50 years, synthetic polymers have been found to steadily replace traditional packaging materials because of their advantages of low cost, low density, inertness, resistance to microbial growth, thermoplasticity, and transparency. However, their usage currently is being partially restricted because they are not totally recyclable and/or biodegradable and thus lead to serious environmental problem. This has resulted in the development of biodegradable polymers/films such as starch, polylactic acid, protein-based film, poly-beta-hydroxyalkanoates (PHB), etc. It has been possible to enhance physico-mechanical and functional properties of such polymers by incorporating organic and inorganic nanoparticles such as silver, titanium, chitosan, cellulose, clay, starch, silica, and zein. Similarly, traditional to coated/laminated paper/paper board, jute fabric, and the corrugated fibre board have been utilized for conventional to high-end packaging.

The effects of deformation and the transition of microstructural defect states with the interchange of solvent and solute in Ti-Zr and Zr-Ti alloys of six different compositions and Zr-Sn alloys in three different compositions have been investigated by X-ray diffraction line profile analysis. The detailed analysis of the X-ray powder diffraction line profiles was interpreted by Fourier line shape analysis using modified Rietveld method and Warren-Averbach method taking silicon as standard. Finally the microstructural parameters such as coherent domain size, microstrains within domains, faulting probability and dislocation density were evaluated from the analysis of X-ray powder diffraction data of Zr base Sn, Ti and Ti base Zr alloys by modified Rietveld powder structure refinement. This analysis confirms that the growth fault, β, is totally absent or negligibly present in Zr-Ti, Ti-Zr and Zr-Sn alloy systems, because the growth fault, β, has been observed to be either negative or very small for these alloy systems. This analysis also revealed that the deformation fault, α, has significant presence in titanium-base zirconium alloy systems but when zirconium content in the matrix goes on increasing beyond 50%, this faulting behaviour suffers a drastic transition and faulting tendency abruptly drops to a level of negligible presence or zero. This tendency has also been observed in Zr-Sn alloys signifying high stacking fault energy. Therefore, Zr and Zr-base alloys having high stacking fault energy can be used as hard alloys in nuclear technology at high temperature.

Electrical transport properties of cobalt doped polyaniline in an aqueous ethanol medium were investigated in the temperature range 77 ≤ T ≤ 300 K, applying magnetic fields up to 1 T in the frequency range 20 Hz–1 MHz. The room temperature dc resistivity increases with increase in Co content. The dc resistivity and magnetoresistivity of these samples have been interpreted in terms of the variable range hopping theory. The frequency dependence of conductivity has been described by a power law σ(ω) ∝ ωS. The value of s is found to be temperature dependent, which shows a decreasing trend with temperature. The correlated barrier hopping model is the most likely mechanism for the electron transport. The different physical parameters were calculated from the experimental data.

Regioselective synthesis of a hitherto unreported furothiopyran moiety fused at the C-5 and C-6 positions of a pyrimidine heterocycle was achieved by the application of sequential Claisen rearrangement in which a second aromatic Claisen rearrangement and intramolecular hydroaryloxylation were catalyzed by aluminum chloride. The second aromatic Claisen rearrangement step was also studied under thermal conditions to give mostly isomerized exocyclic compounds. The precursor endocyclic compounds were synthesized by thermal [3,3] sigmatropic rearrangement of the corresponding sulfide.Key words: aluminum chloride, sequential Claisen rearrangement, hydroaryloxylation, furothiopyran, pyrimidine.

We report the results of a comprehensive study of weak localization and electron–electron interaction effects in disordered V1−xPdx alloys whose compositions are close to the (low Tc) A15 V3Pd compound. Magnetoresistivity and zero field resistivity have been measured within the temperature range 1.5≤T≤300 K. The low-temperature resistivity obeys a ρ o 5 / 2 T 1 / 2 law, which is explained by electron–electron interaction. We have determined the electron–phonon scattering time (τe–ph) for V1−xPdx alloys. Our results indicate an anomalous electron–phonon scattering rate τ e – ph − 1 obeying quadratic temperature dependence. This observation is interpreted by the existing theories of electron–phonon interactions.

Measurement of electrical resistivity in the temperature range 1.5≤T≤300 K of tantalum nitride films prepared by Ion Beam Assisted deposition and pure tantalum films prepared by electron beam evaporation has been carried out. The tantalum film shows a resistivity minimum at Tm=12 K, whereas tantalum nitride shows a decrease in resistivity with an increase in temperature. An attempt has been made to explain such anomalous behavior by using existing theories.

In this Letter we report on the electrical resistivity and magneto-resistivity of disordered V 80 Al 20− x Fe x alloys in the temperature range 1.5⩽ T ⩽300 K and analyze them in the light of weak localization and electron–electron interaction. The low temperature zero field resistivity obeys a T 1/2 law, which is explained by electron–electron interaction. The low field magneto-resistivity is described by weak localization theory under strong spin–orbit interaction. The electron–phonon scattering rate obeys a quadratic temperature dependence. This observation is interpreted by the existing theories of electron–phonon interaction.

We have demonstrated the correlation between the temperature coefficient of electrical resistivity ( α ( T )) and electron mean free path ( l e ) for disordered V 1− x Al x and V 1− x Al x − y Fe y alloys at room temperature in the light of the two quantum mechanical effects like weak localization and electron–electron interaction. The critical resistivity ( ρ c ) of the alloys having temperature exponent of inelastic scattering length, p =1, is not influenced by the electron–electron interaction.

Waste is a substance that is considered by all as unwanted or additional material arising out of any industrial or agricultural operation process, product, by-product, or any other item at the end of their requisite service life. In a country such as the United Kingdom, about 4–5 % of municipal solid waste is composed of clothes/textiles, 25 % of which is recycled. A large amount of unutilised/processed material is generated in the agricultural, food processing, paper–pulp, and textile industries as waste or residue, such as lignin, sericin, dyes, sizing paste, leather fibre, banana pseudostem sap, cellulosic and ligno-cellulosic short to long biofibres, corncob, tomato seed and peel, and many others. The disposal of such waste or residue creates serious environmental pollution, either during their natural degradation, through the microbial pathway, or through incineration. As many of the agro, food, textile, and paper–pulp processing wastes or residues have high technical potential to be used for many diversified end-applications, they have been seriously considered through R&D efforts and application for the production of nanocellulose, microcrystalline cellulose, bacterial cellulose, recovery of dyes, water purification, biodegradable hard and flexible composites, substrates for tissue engineering, recycled textiles, UV protective and antimicrobial agents, binder and biodegradable pots for transplanting of plants, and so on. Life-cycle assessment has also been explored to analyse the environmental performances of different shopping bags.

In the last few decades, people have become more concerned about their health, hygiene, lifestyle, fashion, comfort, luxury, and wellbeing. Those belonging to economically well-off sections are more often choosing to buy luxurious textiles, not only to exhibit their high social and well-off strata, but also from the compulsion in health and hygienic necessity of the present day. In the production of luxurious textiles, natural fibres like cotton, silk and wool, and man-made fibres, like polyester, acrylic and regenerated rayon (viscose) play important roles. Recently, due to the rapid growth of nanoscience and technology, various organic and inorganic nanoparticles, such as silver (Ag), TiO2, ZnO, SiO2, lignin, and Chitosan have been applied to impart attributes needed for health and hygiene, UV protection, self-cleaned, and skin-care functionalities, both in natural and synthetic textiles. Similarly, various plant molecules, biomaterials and bio-polymers, such as banana pseudostem sap (BPS), grape and mulberry fruit extracts, natural dyes, Chitosan, tulsi, silk-sericin, aloe Vera, honey, almonds, cucumber, and mint have been applied in textiles for improvement in antimicrobial, UV-protective, anti-oxidant, skin-nourishing, and hydrophilic properties. Natural extracts of jasmine, lavender, Champa sandalwood and such others containing active ingredients like santalols, fusanol, santene, teresantol, benzyl acetate, linalool, linalyl acetate, and benzyl benzoate have also been added in textiles for their mind-refreshing fragrance and for skin nourishing, smoothening of facial lines/wrinkles and providing impetus to immune, nervous, and brain psychological system. The requirement of various attributes for professional clothing like wrinkle-resistance, comfort and self-cleaning of fabric surface have been incorporated in textiles to develop aristocratic, social, religious, business, and ritual party outfit. High value Cosmeto-textile and Ayurvastra have also been designed for slimming, moisturising, perfuming, healthy, fresh feeling and curing/healing of many diseases in a holistic approach by taking cue from the traditional knowledge of cosmetics, Ayurveda and clothing science. As these high value textiles are produced mostly from the natural fibres and functionalized using natural products/biomaterials, they can be effectively used for the production of sustainable luxurious textiles.

Electrical resistivity and magnetoresistivity of Ti3Ir compound have been measured in the temperature range 2.0 K ≤T ≤ 300 K in absence as well as in presence of magnetic field upto 7.7 T. The low temperature resistivity shows aT2 behaviour whereas the high temperature resistivity shows a linear behaviour. The magnetoresistivity is positive and cannot be explained by simple s-d scattering model. The enhancement of the coefficient A of theT2 term and the deviation from the quadratic field dependence of the resistivity may be due to the anisotropy in the compound.

Measurement of electrical resistivity in the temperature range 77 K ≤T≤300 K and the magnetic hysteresis loops at room temperature of iron nitride films prepared by ion beam assisted deposition have been carried out. Different phases present in the films are identified by using X-ray diffraction. Though saturation magnetization is very low for the Fe2N films, the other phases of iron nitride such as Fe2.5N, Fe4N and Fe3N etc. show saturation magnetization varying from 3.35×10−2 e.m.u. to 12.3×10−2 e.m.u. The coercivity of the films varies with thickness and obeys the d−4/3 law which may correspond to the formation of Bloch wall. The resistivity of all the films obey the T2 variation in the temperature range 77 K ≤T≤300 K. This may be due to electron–spin wave scattering.

X-ray diffraction is an established technique for the analysis of microstructural parameters such as domain sizes, microstrains within the domains, and deformation fault densities in the deformed state of metals and alloys. These microstructural parameters influence the flow of dislocation in the lattice under deformation and thus regulate the strength and hardenability of the materials. The evaluation of such microdefects is this necessary for understanding the mechanical behavior of materials. In the present study, considering the wide applicability of titanium-base alloys in aviation industry, two alloy systems, i.e., titanium-base aluminum and titanium-base zirconium, have been selected. A number of X-ray diffraction profiles belonging to both fault-affected (H {minus} K = 3N {+-} 1) and fault-unaffected (H {minus} K = 3N) reflections have been recorded by a SIEMENS Kristolloflex-4 diffractometer using Cu K{sub {alpha}} radiation, and the profiles have been analyzed to evaluate the microstructural parameters.

Chemical processing of textiles starting from preparatory processing to dyeing and finishing is important for its value addition in terms of fashion and function. However, these processes are water, energy, and chemical intensive and cause serious environment pollution. Recently, because of the increased global awareness of environmental pollution, demand for natural fiber-based textiles dyed with natural dye and finished with various bio-molecules is gaining academic, research and industrial importance. As a result, dyeing of textile has been carried out using various plant extracts because of to the presence of the inherent coloring compound. Some of these dyed textiles have also exhibited excellent UV protective functionality. Antimicrobial, mosquito repellent, well-being, and aroma functionalities have been incorporated into textiles using a number of plant extracts, such as neem, aloe vera, turmeric, arjuna, sandalwood, tulasi, jasmine, and eucalyptus oil. Cellulosic and ligno-cellulosic textile being highly flammable in nature, flame retardancy of such textiles has been improved using banana pseudostem sap (BPS) and spinach extract. The limiting oxygen index (LOI) of such treated fabrics is reported to increase to ≥30 as compared to the LOI value of

Wet chemical processing of textiles requires a large quantity of water as a processing medium, which is finally discharged as an effluent contaminated with residual dyes, pigments, and other hazardous chemicals. However, plasma and UV photons can be effectively used for nanoscale surface engineering of various textile substrates while avoiding the usage of water as a processing medium. Plasma- and UV-induced surface activation, oxidation, etching, increase in surface area/roughness, and polymerization of textile substrates have also been utilized for improvement in water and oil absorbency, dyeing, printing, antistatic, and anti felting properties. Specialty fabrics, such as with one hydrophilic side and other side hydrophobic could also be produced by UV treatment. On the other hand, fragmentation of a precursor molecule in the plasma zone leads to in situ plasma reaction resulting in the development of pinhole-free hydrophobic textiles. In plasma and UV treatment, as only the surface of the sample is modified, they require a minimum amount of chemicals and energy. In addition, the cost of the final product can also be reduced due to the shorter processing time, exclusion of multistep operations, and partial reduction in effluent treatment. In the plasma- and UV-treated samples, the dyeing time, temperature, and dye bath auxiliaries can be reduced to achieve similar or better depth of shade compared to the untreated sample without compromising the fastness properties.