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This work aims to study the effect of mordanting method as pre-mordanting (on-chrome), meta-mordanting (meta-chrome) and post-mordanting (after-chrome) on wool dyeing with madder natural dye without tannin and pomegranates peel, as a natural dye contains tannin.

The woolen yarn was dyed with madder and pomegranate peel natural dyes by three methods as pre-mordant, meta-mordant and pos-mordant. The color parameters and reflectance spectra of dyed samples were analyzed by using derivative spectroscopy and the principal component analysis (PCA) techniques.

The obtained results indicate that the color difference between the samples dyed with madder by pre-mordanting, and the samples dyed by other methods is more than the color difference between the samples dyed by meta-mordanting and post-mordanting. However, the color difference between samples dyed with pomegranate peel by pre-mordanting and meta-mordanting methods is less compared to other pairs. Also, analysis of reflectance spectra and color depth (K/S) values indicate that the color depth of dyed sample with madder by pre-mordanting method is more than other dyeing methods. But, the color depth of sample dyed with pomegranate peel by post-mordanting method is less compared to other methods. The analysis of first-, second-, third- and fourth-order derivatives of reflectance spectra and the study of the first, second, third and fourth PCs of reflectance spectra indicate that the reflectance of dyed samples with madder and pomegranates peel depends on the mordanting method.

Evaluation of the effect of mordanting method on color and reflectance of wool dyed with madder and pomegranates peel natural dyes using derivative spectroscopy and the PCA techniques

To provide a basis for making assessment of the safety of adhesively bonded joints after they have been de‐painted by a dry abrasive method or a wet chemical method.

Stress analysis by a finite element method has been conducted for metal/composite and composite/composite joints in a single lap configuration. The effects of degradation of composite and adhesive, separately or combined, on the stresses in the adhesive layer bonding the two components are studied. Effects of wet and dry conditions of de‐painting are included in the study. It is assumed that in the composite these conditions affect only the laminae close to the surface from which the paint coating is removed.

The locations and values of the maximum peel and shear stresses in the adhesive are determined for both joints under different assumed conditions of degradation caused by de‐painting.

Experimental data indicating the extent of surface damage caused by de‐painting is not available.

Extensive literature study did not show any investigation of composite surface damage and adhesive property degradation on integrity of adhesively bonded joints. Results reported here will be of use in assessing effects of de‐painting on the structural performance of adhesively bonded joints.

The purpose of this paper is to investigate the interfacial nanostructures and the adhesions of the stainless steel (S.S) coating to the polyurethane (PU) and polyvinyl chloride (PVC) leathers.

PU leather and PVC leather deposit S.S nano-films on the surface of PU and PVC leathers in this study. The interfacial nanostructures were investigated by scanning electron microscopy (SEM) and atomic force microscopy (AFM). The experimental results revealed that the surface roughness of the substrates had extremely important influence on the morphology of nano-films. The adhesions of the S.S coating to the PU and PVC leathers were investigated by the peel-off test.

The results showed that the adhesive performance of the S.S nano-films coating on PVC leather was better than that on the substrate of PU leather. Moreover, a weight loss of per peeling force calculating formulation is proposed to determine the bonding strength between the S.S films and the substrates.

In this paper, influence of different substrates on surface morphology of S.S coating was studied by SEM and AFM. Moreover, the weight loss of per peeling force calculating formulation was used to discuss the bonding strength between the S.S coating and the substrates. The research methods presented in this paper are of innovation significance to a certain extent.

One of the popular fields to replace linear economy approach with the sustainable circular approach is the valorization of agri-food waste and by-products by using green methods. Celery peel contains essential nutrients as much as celery root. This study aims to propose a novel framework for investigation of celery root peel waste, which has high nutritional value and is beneficial for healthy nutrition, valorization potential to re-formulate ayran (a traditional Turkish drink).

Sustainable green extraction/distillation methods were applied to the celery root peel material to obtain water soluble extracts to be used in formulation of traditional Turkish drink “Ayran”.

As a result of the study, a new functional fermented drink derived from traditional drink ayran was obtained by using celery root peel extract. In addition to the positive characteristic properties of samples in terms of physical, chemical, microbiological and sensory parameters, it was observed that it increased the shelf life by at least 50% compared to the drink from which it was derived.

Several studies focused the valorization of food waste materials; however, to the best of the author’s knowledge, no study has been taken an approach for using green methods to add additional properties to traditional foods by using celery root peel extracts. Therefore, the study is a remarkable contribution to the circular economy and is a role model for further studies.

This paper aims to evaluate the effects of banana (Musa) peel and guava (Psidium guajava) leaves extract as mordants on jute–cotton union fabrics dyed with onion skin extract as a natural dye.

The dye was extracted from the outer skin of onions by boiling in water and later concentrated. The bio-mordants were prepared by maceration using methanol and ethanol. The fabrics were pre-mordanted, simultaneously mordanted and post-mordanted with various concentrations according to the weight of the fabric. The dyed and mordanted fabrics were later subjected to measurement of color coordinates, color strength and colorfastness to the washing test. Furthermore, the dyed samples were characterized by Fourier transform infrared, and different chemical bonds were analyzed by X-ray photoelectron spectroscopy analysis.

Significant improvement was obtained in colorfastness and color strength values in various instances using banana peel and guava leaves as bio mordants. Post-mordanted with banana peel provided the best results for wash fastness. Better color strength was achieved by fabric post-mordanted with guava leave extracts.

Sustainable dyeing methods of natural dyes using banana peel and guava leaves as bio mordants were explored on jute–cotton union fabrics. Improvement in colorfastness and color strength for various instances was observed. Thus, this paper provides a promising alternative to metallic salt mordants.

The purpose of this paper is to develop the bio-composite organic coatings by adding the bio-based additives that are extracted from banana peels and henna leaves as the organic corrosion inhibitors.

Bioactive constituents with inhibition properties are extracted from banana peels and henna leaves by using ethanol to form the ethanolic extract. The inhibiting efficiency of these bioactive constituents on mild steel corrosion in 3.5% sodium hydroxide (NaCl) solution is investigated. The investigation is performed using electrochemical impedance studies for 30 days. The optical and adhesive properties of the bio-composite coating systems have also been studied.

The best protection is obtained as the loading ratio of the banana peels ethanolic extract (BPEE) and henna leaves ethanolic extract (HLEE) are 10 Wt.% and 30 Wt.%, respectively. Overall, the results obtained show that the BPEE and HLEE not only enhance the optical properties but also can serve as an effective inhibitor for corrosion without affecting the adhesiveness of the neat acrylic properties.

Banana peels and henna leaves consist of bioactive constituents that have anti-corrosion properties which could inhibit corrosion.

During offshore pipe-lay, pipe lengths with anticorrosion coating are welded together, and, to facilitate the welding process, the ends of the pipe remain uncoated. A wide range of field joint coating (FJC) types is available for coating this bare section, functioning in conjunction with the pipeline cathodic protection system to provide an anti-corrosion system or package. This paper aims to relate to two-layer type heat shrink sleeves (2LHSS), which commonly are used for FJC of concrete-weighted offshore pipelines where the sleeve typically is over-coated with a solid or foam type polyurethane “infill”. Similar sleeves also are used sometimes in exposed conditions on lines without concrete over-coating. The maximum allowable soluble salt contamination prior to application of high-performance coating systems can vary, depending upon the coating type, but typically has been set at 20 mg/m2 (de la Fuente et al., 2006). The first layer of three-layer heat shrink sleeve (3LHSS) systems for pipeline FJC, liquid epoxy, falls into this category (ISO_21809-3:2008, 2008). In contrast, the 2LHSS system does not use a liquid epoxy first layer but relies instead on the bonding of a “mastic” layer directly to the pipe metal surface. The maximum acceptable concentration of salt contamination on prepared metal surfaces prior to the application of 2LHSS has been a subject of debate and was the focus of this study. International standards for FJC do not provide a maximum salt level. However, some companies have continued to specify low thresholds for the maximum allowable salt level for 2LHSS, which can result in expensive delays in production during offshore pipe-lay. In this study, salt contamination levels of up to 120 mg/m2 were found to have no effect on peeling performance after accelerated aging by hot water immersion. Furthermore, preparation for welding and the use of potable water during ultrasonic testing procedures prior to FJC, typically reduces the salt contamination level to below 50 mg/m2 providing a strong case for the deletion of salt contamination testing for 2LHSS.

The potential risk of failure of the coating due to poor surface cleanliness/contamination was assessed by testing the adhesion between the coating and the steel substrate to which the coating is adhering, following a period of hot water immersion. Compliance with ISO 21809-3 “Annex I” requires 28 days’ immersion at maximum operating temperature. For this study, to create a severe situation, the test rings were subjected to accelerated aging by water immersion at the HSS upper specified temperature of 65°C for more than twice the specified period (ISO_21809-3:2008, 2008). Two HSS were tested; one was widely used in applications where exposure to moderate mechanical stress is required, having a high shear strength type mastic “hybrid” adhesive containing a significant proportion of amorphous polypropylene blended with tackifiers and ethylene vinyl acetate (EVA), Andrenacci et al. (2009) referred to as “Type A”. The second, referred to as “Type B”, is widely used in applications where it is covered by a layer of “infill”, typically consisting of polyurethane foam or solid polyurethane elastomer, i.e. typical design methodology for concrete coated pipelines. “Type B” HSS had a more moderate strength traditional type mastic than “Type A” containing a significant percentage of butyl rubber with asphalt, activation agents and tackifying resins. To determine how to apply the salt contamination without causing flash rust, a mini-study was completed on the steel substrate. After numerous trials, it was found impossible to not to form visible rust on the pipe surface. The extent of rusting was minimised by heating the pipe immediately after the application of the salt solution.

High levels of sea salt on power tool prepared pipe surfaces were investigated by peel testing of 2LHSS after hot water immersion and compared against peel tests undertaken prior to hot water immersion. The test conditions were considered severe: salt contamination levels of up to 120 mg/m2 applied on power tool cleaned pipe surfaces that had been aged for one year without prior grit blasting. The accelerated ageing procedure had twice the specified (ISO_21809-3:2008, 2008) water immersion duration, and the test samples had exposed edges providing the possibility for moisture to creep under the coating. The test results showed that there were no noticeable deleterious effects on the performance of the two most commonly used FJCs, 2LHSS. Therefore, it was concluded that, as the level of salt contamination on prepared pipe surfaces after wet non-destructive testing typically is much lower than the levels tested in this study, pipe surfaces prepared for the application of 2LHSS type do not require specific additional measures to further reduce salt contamination, provided that care is taken to ensure that these conditions are maintained consistently during pipe laying operations.

The frequency of salt contamination testing of power tool cleaned surfaces prior to mastic type heat shrink sleeves can be minimised, and perhaps omitted entirely, provided the above criteria are satisfied.

A literature review revealed there was little published information on the testing of 2LHSS and nothing related to hot water immersion testing. Hence, the results of this investigation have provided useful industrial data regarding the effect of hot water ageing and the influence of surface salt contamination on field joint corrosion prevention capabilities.

In the livestock industry in Nigeria, maize is a major source of energy and it is expensive because of competition between man and animal. Dry plantain peel of minimal cost was used to replace the maize fraction of the diet of rabbit in order to reduce cost. The purpose of this paper is to examine the performance characteristics of rabbit fed plantain peel.

The feeding trial had five treatments, T₁, T₂, T₃, T₄ and T₅ in which the maize fraction in the diet was replaced at 0, 25, 50, 75 and 100 per cent, respectively. Completely randomized designs were used and each treatment was replicated thrice with three rabbits per replicate. The parameters taken were feed intake and weight gain on a daily and weekly basis. Feed conversion ratio, total feed cost and cost per weight gain were calculated.

The results show that there was no significant difference in the weight gain between the control diet (T₁) and T₃ (p < 0.05). The feed conversion ratio was relatively similar in T₁ and T₄. The cost per weight gain reduced from N53.57 in the control diet to N33.39 in T₃ (75 per cent replacement).

In the livestock industry, maize is expensive because it serves as food for both man and animal. The results indicate that the feed cost of rabbit could be reduced by replacing the maize fraction of the diet with 75 per cent dry plantain peel.

Flours obtained from pulps and peels of unripe banana were evaluated regarding their chemical composition and glycemic responses in rats. Moreover, this study aims to propose a new assay to measure glycemic responses using animals.

Proximal composition, total dietary fiber and its insoluble and soluble fractions, mineral content and tannins were evaluated. Glycemic responses were measured using albino Wistar rats (seven animals/group).

Flours from pulp and peel of unripe banana presented high content of carbohydrates and minerals. Moreover, flour from peel was rich in insoluble fiber, whereas flour from pulp had adequate proportion of insoluble and soluble fractions. Consumption of banana flours from peel and pulp did not affect fasting blood glucose of normoglycemic rats. Flour from pulp, when consumed in concentrations of 10 and 15 per cent of the diet, significantly stimulated lower glycemic responses in the animals.

Results presented in this study disclose unripe banana flour as an interesting food source, which may be indicated for preventing some types of diseases, such as diabetes, obesity and dyslipidemia. Moreover, the glycemic index assay using animals promoted accurate answers, as the diets were standardized, unlike studies with humans, which do not control variations related to omission and distortion of information regarding food intake.

The purpose of this study is to investigate the effects of two epoxy ratio and carboxyl-terminated butadiene solid rubber (CTBN) content on adhesive and flexible copper clad laminate (FCCL) performance. The epoxy adhesive used for FCCL was prepared with epoxy resin of 901 and 6128 as matrix and CTBN as toughener.

The epoxy adhesive was prepared with epoxy resin as matrix, CTBN as toughener and 4,4′-diamino diphenyl sulfone as curing agent in solvent of butanone by mechanical agitation. The adhesives were cast on the polyimide film; subsequently, the polyimide film was dried at 160°C for 3 min to remove the solvent. Then, it was laminated with copper foil at 180°C with the pressure of 12 MPa for 3 min. The FCCL was obtained after heating for 3 h in a vacuum oven at 160°C. The structure and dielectric properties of cured adhesive, surface morphology of peeling FCCL and mechanical properties of FCCL were determined.

CTBN was found to react with the epoxy resin during the curing process, with the rubber phase being precipitated and dispersed in the epoxy matrix. The relative dielectric constant and the dielectric loss tangent slightly increased with increasing CTBN content. The peeling strength of FCCL increased accompanied by a decrease of folding resistance with the increase of 901 content. Further, with the addition of XNBR, the peel strength of FCCL increased, as well as the folding resistance of FCCL, but at a higher XNBR level of 20 weight per cent, the folding resistance of FCCL tended to decrease.

In the study reported here, the effects of different epoxy resin molecular weight and CTBN content were investigated. Results of this research could benefit in-depth understanding of the influence of epoxy resin molecular weight and CTBN content on adhesive performance and could further promote the development of epoxy adhesive.

The adhesion of epoxy adhesive prepared from epoxy resin with different molecular weight and CTBN increased, leading to the increase in peeling strength and folding resistance of FCCL.

The peeling strength of FCCL increased as the adhesion strength of epoxy adhesive increased by adding CTBN, making FCCL widely applicable.

The mechanical properties of epoxy adhesive were increased by adding CTBN. The effects of CTBN on the microstructure and properties of FCCL were discussed in detail.