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The purpose of this paper is to present a new test method (tape peel method) to evaluate conformal coating adhesion to electronic assemblies.

The key issue for this method is the low cohesive force of conformal coatings, and hence selection of a supporting material to peel the coating from the substrate is critical. A suitable cloth material (35 per cent cotton +75 per cent polyester with 20 per cent open area) has been selected as a peel tape, and achieved the best bonding with coatings, and the smallest affect on the coating curing process. Using the tape, the peel force of the coating from the electronic assembly, can be measured quantitatively, and hence the adhesion performance of the conformal coating assessed.

The method was validated using different coating types, substrate materials (bare laminate with and without resist, copper clad laminate, and contaminated laminate material), assemblies and components. The results demonstrated that the tape peel test is a sensitive method for measuring coating adhesion on different materials found on PCB assemblies. Coating adhesion was found not to be effected by a wide range flux residues, but components and some resists presented a far greater coating challenge, with some coatings achieving very low adhesion values.

This new method for evaluating conformal coating adhesion to electronic assemblies will be of benefit to coating developers and users, and help to minimise adhesion failures in service. The test has been demonstrated to be sensitive to a number of process and material variables.

Peel strength numbers are part of a laminate's specifications and should characterize the specific bond performance (copper adhesion) under test conditions. Unfortunately, from both a theoretical and a practical point of view they are not able to do that. This study seeks to address this issue.

This paper has been written to show the main impacts on the measured peel strength numbers in the IPC‐TM‐650 peeling test. From an extensive database regarding peel numbers for diverse foil types, foil thicknesses and treatment roughnesses it is possible to show the influence of prepreg type, foil thickness and roughness on the measure peel strength.

Copper adhesion to laminating resin is insufficiently described by peel strength data because of the impacts of foil thickness, stiffness on bending (physical bending work, stress distribution underneath the peeling line) and the treatment roughness. The latter works reinforcing regarding the (low) resin strength and this influence is measured on resin strength instead of real bond. Fracture due to peeling is cohesive, mostly with a totally intact copper‐resin interface. This is especially true in high performance laminates that show low peel strengths not because of bad copper bonding but because of brittle resins (filled and unfilled).

Users have to understand the limited benefit of the IPC peel test in characterizing copper‐resin bonds. Peel increase on (low bond) high performance resins by increased foil roughness is not a practical way in the field because of no bond improvement (interface) and heavy disadvantages in dielectric thickness (HiPot tests at thin core laminates), respectively.

The objective was to evaluate the effect of banana peel into cake (a bakery product that may add bananas) and panettone (a product that never is added to bananas) formulations on consumers' acceptance and perceived attributes and the effect on the technological properties of the product.

Bakery products were produced with banana peel in the formulation and control samples without residue. Volunteers scored their acceptance and checked all attributes applied to the four samples in the blind and informed tests. The texture, color, proximate composition and bake properties were measured.

The acceptance of both cakes, with and without banana peel, was not affected when consumers were informed that there was a residue in both cakes. Relative risk indicated that information had no influence on acceptance. Panettone with banana pulp showed a reduction in acceptance when volunteers were informed of the presence of banana peel. Risk analysis showed a significant relative risk of product rejection when consumers were aware of information. The addition of banana peel enhanced panettone chewiness and crumb hardness, reduced bake loss of cakes, reduced the volume of both products and changed some color parameters of both products.

Banana peel is a source of functional compounds, but it is not clear how consumers react when informed that the food presents it.

This study aims to investigate the potential use of potato peel extracts as antibacterial finishes for cotton fabrics against Staphylococcus aureus and Escherichia coli. Potato peels are abundant as waste and provide a natural, cheaper and sustainable alternative means of preventing the spread of bacterial infections on cotton fabric.

This research included the characterization of potato peel extracts, application of the extract onto cotton fabric and efficacy testing of the treated cotton fabric against bacteria. Phytochemical screening, agar well diffusion antibacterial test, minimum inhibitory concentration and Fourier transform infrared (FTIR) tests were used to characterize the extract. Antibacterial efficacy of the treated fabric was determined qualitatively using the disc diffusion assay and quantitatively using the bacteria reduction test.

Phytochemical screening confirmed the presence of several secondary metabolites including phenols and flavonoids. Antibacterial tests revealed a positive response in Escherichia coli and Staphylococcus aureus with a zone of inhibition of 6.50 mm and 5.60 mm, respectively. Additional peaks on the FTIR spectroscopy confirmed the presence of potato peel extract on the treated cotton fabric. The treated cotton fabrics showed efficacy against Staphylococcus aureus and Escherichia coli up to 20 washes.

This study introduced the application of potato peel extracts onto cotton fabrics and assessment of the antibacterial properties before and after washing. Results of this study suggest that potato peel extracts can be used as an organic eco-friendly antibacterial finish for cotton fabrics.

The purpose of this paper is to evaluate the relationship between the Cu trace and epoxy resin and to check the validity of surface and interfacial cutting analysis system (SAICAS) by comparing its results to those of the 90° peel test.

In this study, the effects of surface morphology on the adhesion strength were studied for a Cu/epoxy resin system using a SAICAS. In order to evaluate the peel strength of the sample, the curing degree and surface morphology of the epoxy resin were varied in the Cu/epoxy resin system.

The results indicated that the peel strength is strongly affected by the curing degree and the surface morphology of the epoxy layer. As the pre-cure time increased, the interactions between the epoxy resin and permanganate during the adhesion promotion process decreased, which decreased the surface roughness (Ra) of the resin. Therefore, the surface roughness of the epoxy resin decreased with increasing pre-cure time. The curing degree was calculated with the FTIR absorption peak (910 cm−1) of the epoxy groups. The high curing degree for the epoxy resin results in a coral-like morphology that provides a better anchoring effect for the Cu trace and a higher interfacial strength.

It is necessary to study the further adhesion strength, i.e. the friction energy, the plastic deformation energy, and the interfacial fracture energy, in micro- and nanoscale areas using SAICAS owing to insufficient data regarding the effects of size and electroplating materials.

From findings, it is found that measuring the peel strength using SAICAS is particularly useful because it makes the assessment of the peel strength in the Cu/epoxy resin system of electronic packages possible.

Salak (Salacca zalacca) is an underutilised fruit. The bioactivities of this fruit have rarely been studied scientifically. Thus, the present study aimed to determine the antioxidant activity of extracts derived from the peel, fruit and kernel of the Salak fruit, as well as the hypoglycemic and anti-hypertensive properties of Salak peel extracts.

The peel, fruit and kernel of the Salak were extracted using distilled water, methanol and ethanol. Antioxidant activities, angiotensin-converting enzyme (ACE) and alpha-amylase inhibition properties of the extracts were estimated via in vitro standard methods. Besides, the total phenolic content (TPC) and total flavonoid content (TFC) of the extracts were also determined in the present study. The antioxidant activities of different parts of Salak extracts were determined by ferric-reducing antioxidant power (FRAP) and Trolox equivalent antioxidant capacity (TEAC) methods. Percent of radical scavenging properties were calculated via DPPH assay. The hypoglycemic and anti-hypertensive properties of Salak peel were evaluated using alpha-amylase inhibition and ACE assays, respectively.

Fruit extracts of Salak in methanol were found to exhibit the highest TPC (10.27 ± 0.12 mg GAE/g), TFC (11.04 ± 0.89 mg CE/g) and antioxidant properties amongst all samples whereby the TPC and TFC were strongly correlated with antioxidant activities. On the other hand, distilled water extracted Salak kernel showed to have the lowest TPC (0.53 ± 0.05 mg GAE/g), TFC (0.37 ± 0.01 mg CE/g) and antioxidant properties amongst all the Salak extracts. Peel extracts exhibit comparable antioxidant activities with fruit extracts in the current findings. In addition, peel extracts indicated some extend of ACE and alpha-amylase inhibition activities regardless of the solvents used. Methanol and ethanol peel extracts indicated no significant difference (p < 0.05) ACE (98%) and alpha-amylase (90%) inhibition activities. However, distilled water extracted Salak peel showed significantly lower ACE and alpha-amylase inhibition in comparison to methanol and ethanol peel extracts.

The present findings suggested that the fruit of Salak exhibits the highest antioxidant properties, followed by the peel and lastly, the kernel, which shows the lowest antioxidant properties amongst all the samples. The results also indicated that the peel extracts have ACE and alpha-amylase inhibition activities.

The purpose of this study is to explore the possibility of utilization of lemon peel extract as a natural antioxidant source in muscle foods. The products incorporated with lemon peel extract were assessed for various oxidative stability and storage quality parameters.

The study was designed to evaluate the effect of lemon peel extract on the oxidative stability and storage quality of Tabak-Maz, a popular traditional meat product. The products were prepared and treated with different concentrations of lemon peel extract (0.5, 1, 1.5 per cent) and were aerobically packaged in low-density polyethylene pouches and assessed for lipid stability and storage quality parameters under refrigerated (4 ± 1°C) conditions.

Lemon peel extract showed a significant (p < 0.05) effect on the lipid stability of the products as the treated products exhibited significantly (p < 0.05) lower thiobarbituric acid-reactive substances (TBARS) (mg malonaldehyde/kg) and free fatty acid (FFA) (per cent oleic acid) values for the entire period of storage. A significant (p < 0.05) effect was also observed on the microbiological characteristics of the products, as lemon peel extract treated products showed significantly (p < 0.05) lower values for total plate count, psychrophillic count and yeast and mould count throughout the period of storage. Coliforms were not detected throughout the period of storage. Significantly (p < 0.05) higher scores were observed for various sensory parameters of the treated products.

Lemon peel extract successfully improved the oxidative stability and storage quality of Tabak-Maz during refrigerated (4 ± 10°C) storage and may be commercially exploited as a natural antioxidant source in muscle foods.

This paper aims to describe a new process for suppressing the formation of orange peel, which is a polymer laser sintering (LS) process error.

The target for controlling the suppression of orange peel is securing the contact between the molten polymer and the surrounding powder. The authors set the powder bed temperature closer to the melting temperature than that for a typical LS. Alternatively, the authors use a low-power laser to irradiate the powder bed surrounding the parts being built. The surface finish of the built parts was evaluated using a three-dimensional scanner.

Both approaches were effective in suppressing orange peel. From the viewpoint of reusability of the used powder, the process that includes low-power laser irradiation is practical. The presence or absence of contact between the surrounding powder and the molten polymer determines whether the orange peel is formed.

The authors have not tested orange peel suppression for complex shapes.

The authors have demonstrated a concrete process that can suppress orange peel formation even for powders with low melt-flow rates. Furthermore, a mechanism for the formation/suppression of orange peel based on the experimental results was proposed.

The purpose of this paper is to substitute wheat flour by passion fruit peel flour in Brazilian honey bread (pão de mel), with evaluation of the breads’ sensory features, chemical composition and physical properties.

Honey breads with wheat flour (standard) and with replacement of this ingredient by 10 to 50 per cent passion fruit peel flour were produced. Two sensory tests were applied, to identify how different formulations with passion fruit peel flour were when compared to the standard formulation, and also the acceptability of the products. The selected honey breads, through sensory results, were evaluated regarding to chemical composition and physical properties.

Formulations with 10 and 20 per cent substitution were the least different to formulations with only wheat flour, and were as acceptable as the wheat flour sample. Physical and chemical characteristics of breads with 10 and 20 per cent passion fruit peel flour were similar; however, honey bread with 20 per cent passion fruit peel flour had higher fibre content, ash quantity and hardness value; a lower specific volume; and a different colour from the wheat flour sample.

This study offers an opportunity to food industries through utilization of an agro-industrial by-product on the formulation of a Brazilian traditional product.

This study presents the feasibility of using an agro-industrial by-product to Brazilian honey bread, enhancing the nutritive value of this product and reducing the impact of passion fruit peel flour on the environment.

The effect of pomegranate whole and inside peels before and after extraction of the tannic acid have been carried out in stimulated media and in gastrointestinal conditions

Adding pomegranate peels with and without tannins at different levels to bio-stirred yoghurt to study its effect as prebiotic, in addition to evaluating the effect on physiochemical, sensorial and rheological properties

The results reveal that pomegranate peels before and after removing tannins had no effect on the viability of a single strain of Lb. acidophilus in stimulated media, while the growth of mixed probiotic culture (Lb.acidophilus and Bifidobacterium bifidum) was enhanced when pomegranate peels (whole and inside part) free from tannins were used. Tannin-free pomegranate peels enhanced the viability of probiotic culture under gastrointestinal conditions. In this study, all probiotic cultures were maintained counts around log 8 cfu /g in stirred bio-yoghurt supplements with pomegranate peels after 21days. Bio-yoghurt supplemented with pomegranate peels at 0.5% gained high scores for overall acceptability.

Pomegranate has been recognized as a good source of antioxidant and antimicrobial activities. Some researchers have utilized pomegranate peel in fermented milk, but most of the studies have found that tannins inhibit the bacterial culture. This study recommended that the supplementation of low-fat bio-yoghurt with tannin-free pomegranate peels enhanced the texture properties, viscosity of the product, as well as the viability of probiotic culture during shelf life. Therefore, the tannin-free pomegranate peel could be used as a prebiotic in functional fermented dairy products.