Surface Peeling Research Articles

High-performance humidity sensor for multipurpose applications by recycling of potato peel bio-waste

This study suggests the development of a biocompatible and eco-friendly humidity sensor fabricated by using a naturally available potato peel bio-waste as the substrate and the humidity sensitive material. Entire fabrication process of this potato peel-based humidity sensor (PPHS) took less than two minutes owing to the facile and handmade patterning of silver interdigitated electrodes on the surface of dry potato peel. The fabricated humidity sensor yielded a high sensitivity (70 kΩ/ % RH) due to the presence of abundant polar hydrophilic functional groups. The achieved results were stable for more than seven days and repeatable data was obtained for three different samples. Furthermore, a quick response/recovery time of 0.96/1.65 s was recorded for nose breathing with a small hysteresis of only 0.21 % for adsorption and desorption process. The sensor exhibited a good linearity (R2 = 0.997) in the practical applications-based humidity sensing range of 40–85 % RH. Efficient use of PPHS was successfully demonstrated in multiple applications including medical diagnosis, skin care, real-time environment monitoring and touchless sensing owing to its biocompatibility and nonhazardous nature. In addition to the above listed multifunctional applications of PPHS, economic use of potato peel in commercial devices can help in recycling the worldwide wastage of this bio-waste.

Salt-induced structure damage and permeability enhancement of Three Gorges Reservoir sandstone under wetting-drying cycles

The salts contained in water can gradually accumulate in pore networks of rocks under wetting-drying cycles, which could cause rock deterioration. The salt-induced damage under this cyclic process can result in dynamically evolving mechanical and hydraulic properties of the rock, which is relevant to many rock-related engineering activities and geological hazards. In this study, the structure damage and permeability evolution of Three Gorges Reservoir (TGR) sandstone subjected to wetting-drying cycles with salt solution were investigated by a series of multiscale experiments. The results showed that the salt solution has a significant impact on the physical properties of TGR sandstone during the wetting-drying process. With increasing wetting-drying cycles, two typical macroscopic damage modes in form of surface peeling and internal cracking were observed. Various physical parameters indicated that the internal structure of the TGR sandstone experienced two stages: 1) Salt accumulation and new crack formation stage and 2) Crack propagation stage. This variation also profoundly affected the permeability of the TGR sandstone. Specifically, the permeability of TGR sandstone decreased slightly at first due to blocked seepage channels by crystals before cycle 5, followed by a slow growth until the 15th cycle and a rapid increase after the 15th cycle. Cubic and exponential functions showed good performances to describe the evolution features of permeability with porosity and wetting-drying cycles, respectively. The deterioration mechanism was further elucidated by an evaporation test. This test indicated that the salt solution was more likely to crystallize in narrow pores and expectedly exert pressure enough to crack the pores, contributing to the structure damage feature and the permeability enhancement. These findings and results in this study deepen our understanding of salt-induced rock deterioration mechanism under the wetting-drying cycles and would be meaningful for rock engineering safety and geological disaster forecast in complex groundwater environments.

Garlic peel as promising low-cost support for the cobalt nanocatalyst; synthesis and catalytic studies.

The development of cost-effective and applied catalysts for organic pollutants degradation is the cornerstone for the future valorizations of these hazardous wastes. Garlic peel was employed as solid support for the assembly of cobalt nanoparticles and was further applied for the catalytic degradation of 4-nitrophenol, bromophenol blue, and a mixture of both. A Cobalt@garlic peel nanocomposite with the morphology of semi-spherical and randomly distributed nanoparticles was prepared without the aid of any hazardous chemicals. The functional groups facilitated the adsorption of cobalt ions onto the surface of garlic peel through van der Waals forces and/or hydrogen bonds. The catalytic experiments were carried out under different operational parameters including pollutant concentration, catalytic dosage, and pH value to identify the optimal conditions for the model solutions. The results showed that the optimal pH for 4-nitrophenol degradation was around 9 and the maximum rate constant 4.56 × 10−3 sec−1. The most prominent feature of the proposed catalyst is the easy/efficient recovery and recycling of the nanoparticles from the reacting medium. This work provided a simple method for designing other similar biomass-stabilized nanocatalysts which might sharply reduce the catalytic treatment costs and broaden the scope of applications.

Interfacial Shear Performance of Epoxy Adhesive Joints of Prefabricated Elements Made of Ultra-High-Performance Concrete.

Application of ultra-high-performance concrete (UHPC) in joints can improve the impact resistance, crack resistance, and durability of structures. In this paper, the direct shear performance of ultra-high-performance concrete (UHPC) adhesive joints was experimentally studied. Twenty-four direct shear loading tests of UHPC adhesive joints were carried out considering different interface types and constraint states. The failure modes and load-slip curves of different interfaces were studied. Results indicated that passive confinement could enhance the strength and ductility of the interface; the average ultimate bearing capacity of the smooth, rough, grooved, and keyway specimens with passive restraint were, respectively, increased by 11.92%, 8.91%, 11.93%, and 17.766% compared with the unrestrained ones. The passive constraint force changes with the loading and finally tends to be stable. The epoxy adhesive has high reliability as a coating for the UHPC interface. The adhesive layer is not cracked before the failure of the specimen, which is also different from the common failure mode of adhesive joints. Failure of all specimens occurred in the UHPC layer, and the convex part of the groove interface shows the UHPC matrix peeling failure; the keyway interface is the shear damage of the key-tooth root, and the rest of the keyway showed UHPC surface peeling failure. According to the failure mode, the shear capacity of UHPC keyway adhesive joints under passive restraint is mainly provided by the shear resistance of key teeth, the friction force of the joint surface, and the bonding force of the UHPC surface. The friction coefficient was determined based on the test results, and the high-precision fitting formula between the shear strength of the UHPC surface and the passive constraint force was established. According to the Mohr stress circle theory, the proposed formula for direct shear strength of UHPC bonded joints under passive constraint was established. The average ratio of the proposed UHPC adhesive joint calculation formula to the test results was 0.99, and the standard deviation was 0.027.

Microwave-assisted infrared dry-peeling of beetroot: Peeling performance, product quality, and cell integrity

The use of low power-short time microwave (MW) treatment before infrared (IR) heating could help improve the peeling performance of beetroot. MW-assisted IR peeling (MWIR) and IR peeling of beetroot were investigated and compared with the conventional hot-lye peeling method. Also, the effects of these peeling methods on the quality and microstructure were evaluated. Hot-lye peeling at 95 °C for 40 s and 60 s was used as control. Results showed that MW-assisted IR peeling at power 640 W and heating time 7 min produced samples with the highest peelability (99.4%), lowest peel thickness (0.075 mm), and peel remaining (0.8%), lower peeling loss (4.23 g), and better peeling easiness when compared with lye peeling and IR peeling. IR peeling alone produced samples with the lowest peeling loss (2.87 g) and surface colour change, and the highest vitamin C retention (75.32%) than MW-assisted IR and lye peeling respectively. The product microstructure for the different peeling methods showed cellular distortion as a result of thermal expansion. MW pretreatment shows a promising potential to further develop the IR dry-peeling method, to replace the conventional hot lye chemical peeling.

BONDING PROPERTIES OF Al/Al2O3 BULK COMPOSITES PRODUCED VIA COMBINED STIR CASTING AND ACCUMULATIVE PRESS BONDING

In this study, Al/Al2O3 composites have been fabricated by combined stir casting and accumulative press bonding (APB) processes. The effect of APB method on the bonding properties of bulk samples such as the number of APB process, Al2O3[Formula: see text]wt.% and the pressing temperature has been investigated by the peeling test. It is established that stronger bonding with a good quality can be obtained by increasing the pressing temperature and decreasing the Al2O3 particles[Formula: see text]wt.% as the reinforcement. Also, growing the step number of the APB method increases the bonding strength up to step#2 and then reduces the average peeling force due to the strain hardening result of the metallic matrix during the accumulative pressing. Finally, the effect of the APB method on the peeling surface of samples has been investigated using the scanning electron microscopy.

Rapid On-site identification of geographical origin and storage age of tangerine peel by Near-infrared spectroscopy

The feasibility of identifying geographical origin and storage age of tangerine peel was explored by using a handheld near-infrared (NIR) spectrometer combined with machine learning. A handheld NIR spectrometer (900–1700 nm) was used to scan the outer surface of tangerine peel and collect the corresponding NIR diffuse reflectance spectra. Principal component analysis (PCA) combined with Mahalanobis distance were used to detect outliers. The accuracies of all models in the anomaly set were much lower than that in calibration set and test set, indicating that the outliers were effectively identified. After removing the outliers, in order to initially explore the clustering characteristics of tangerine peels, PCA was performed on tangerine peels from different origins and the same origin with different storage ages. The results showed that the tangerine peels from the same origin or the same storage age had the potential to cluster, indicating that the spectral data of the same origin or the same storage age had a certain similarity, which laid the foundation for subsequent modeling and identification. However, there were quite a few samples with different origins or different storage ages overlapped and could not be distinguished from each other. In order to achieve qualitative identification of origin and storage age, Savitzky-Golay convolution smoothing with first derivative (SGFD) and standard normal variate (SNV) were used to preprocess the raw spectra. Random forest (RF), K-nearest neighbor (KNN) and linear discriminant analysis (LDA) were used to establish the discriminant model. The results showed that SGFD-LDA could accurately distinguish the origin and storage age of tangerine peel at the same time. The origin identification accuracy was 96.99%. The storage age identification accuracy was 100% for Guangdong tangerine peel and 97.15% for Sichuan tangerine peel. This indicated that the near-infrared spectroscopy (NIRS) combine with machine learning can simultaneously and rapidly identify the origin and storage age of tangerine peel on site.

Microwave vacuum drying of pomegranate peel: Evaluation of specific energy consumption and quality attributes by response surface methodology and artificial neural network

Microwave vacuum drying of pomegranate peel was studied through this work and the drying process was modeled with the aid of response surface methodology (RSM) and artificial neural network (ANN) method. The drying experimental runs were performed on varied ranges of microwave power (175, 330, and 485 W) and vacuum pressure (10, 15, and 20 kPa) using a face-centered composite design. The influence of process parameters on five target responses, namely: total hydrolysable tannin (THT), color change (ΔE), maximum temperature evolved (Tmax), effective moisture diffusivity (Deff), and specific energy consumption (SEC) were analyzed. For microwave power and vacuum, the optimal conditions attained with aid of RSM and ANN were 260 W, 15.59 kPa, and 287 W, 19 kPa, respectively. The THT retention, ΔE, Tmax, Deff, SEC determined with RSM and ANN optimized values were 78.51 mg TAE/g of DW, 13.48, 67.02°C, 3.38 × 10−6 m2/s, 20.02 kWh/kg and 90.32 ± 0.35 mg TAE/g of DW, 12.488, 64.83°C, 5.64 × 10−6 m2/s, 20.01 ± 0.33 kWh/kg, respectively. The influence analysis explained that pomegranate peel dried at optimized ANN conditions of microwave power 287 W and vacuum 19 kPa possessed improved physicochemical properties and was efficient in terms of energy consumption compared to peel dried using RSM suggested conditions. Furthermore, the major criterion for evaluation between RSM and ANN tools in this study was the goodness of fit. The value for R2 produced via RSM varied between 0.8354 and 0.9870, whereas subsequent R2 in the case of ANN was considerably greater, varying between 0.9213 and 0.9956. The mean square error value displayed the minimum value in the case of ANN compared to the RSM model. These signified rather greater exactness and predictive capability of the ANN tool. Fourier transform infrared analysis established the existence of peaks between 3,308.92 and 908.89 cm−1 and high-performance liquid chromatography showed that pomegranate peel produced using microwave vacuum drying contains a good amount of gallic acid and tannic acid derivative compounds. Scanning electron microscopy elucidated that the combined microwave vacuum effect resulted in the formation of bigger pores on the peel surface ensuing in elevated extraction of THT at reduced energy consumption. Practical applications Shifting into a bio-economy is unrealistic with no proficient use of agricultural by-products and food waste. Microwave vacuum drying is a novel technique that would be applied to preserve the product bioactive components while drying. This study has established that drying of waste pomegranate peel using microwave vacuum dryer aided in excellent recovery rate of bioactive compounds particularly hydrolysable tannin (strong antioxidant and antimicrobial agent). This promises pomegranate peel powder obtained using microwave vacuum drying to be utilized in functional and nutraceutical food processing industries as a prospective resource of antimicrobial and antioxidant compounds. The findings also identified that the ANN-GA (artificial neural network–genetic algorithm) model would be effective for modeling the microwave vacuum drying method of pomegranate peel with preservation of peel quality. The optimal process values attained using coupled ANN-GA tool could be applied with respect to microwave vacuum-based industrial dryers to achieve the objective of drying at a considerably quicker rate.

Effect of laser plasma on Nd:YAG laser drilling of acrylic plate with high optical density

Laser material processing (LMP) is used to replace traditional material processing techniques, such as material cutting, thin plate drilling, and surface processing. When a high-energy laser is projected onto a material, the temperature of the material increases rapidly, changing the characteristics of the material and making the material on the surface vaporize and peel off instantly. In this study, we developed a laser system using a Quantel Brilliant neodymium-doped yttrium aluminum garnet (Nd:YAG) with a wavelength of 1064 nm laser a pulse width of 5–6 ns, a beam diameter of the 6 mm, and 10 repetition rate (Hz) on the energy stability is within 5.60%, an F-theta lens is used to obtain a focused laser beam with a diameter of 0.2 mm. The developed system was employed to drill holes in a 3-mm-thick optical-grade acrylic polymethyl methacrylate (PMMA) plate with high optical density and 7 + safe windows. A laser-safe, flat-window, visible-light-transmitting (VLT) sample was used, and the material to be drilled was a PMMA plate. The laser beam must be focused on the center of the F-theta lens and must be aligned with the distance between the F-theta lens and the linear stage. The working distance was set to 300 mm. Furthermore, the diameter was adjusted to obtain the laser plasma effect; that is, the working distance was fixed. First, the characteristics of the laser plasma and the ability of the laser to penetrate optical-grade acrylic (PMMA) plates samples were studied. By changing the lifting position of the vertical axis and varying the working distance of the acrylic (PMMA) plates, the laser beam was targeted at different positions on the acrylic (PMMA) plates. To determine the optimal parameters for the drilling process, a pulsed laser output of 174.7 mJ/pulse (3000 pulses in 5 min) was focused on the hole. Results showed that the energy was 522.98 J/cm2; a laser energy density of 141.26–275.93 J/cm2 resulted in an acceptable heat-affected zone. The Nd:YAG pulsed laser can produce laser plasma that can increase the hole diameter by up to 50% because of the produced cavity gap. Various exit and entrance hole shapes can be achieved and thus employed for different applications, such as laser beam cutting.

СРАВНИТЕЛЬНАЯ ЭФФЕКТИВНОСТЬ СПОСОБОВ ОБРАБОТКИ ПОЧВЫ В РЕГУЛИРОВАНИИ ЗАСОРЁННОСТИ ПОСЕВОВ СЕЛЬСКОХОЗЯЙСТВЕННЫХ КУЛЬТУР

The article presents the results of evaluating the anti-weed effectiveness of the methods of basic tillage and their effect on the quantitative and species composition of weeds in the field crop rotation with the following alternation: 1-h / pair; 2-winter wheat; 3-spring wheat; 4-mustard (siderate); 5-winter wheat; 6-barley. The research was carried out on the experimental field of the Ulyanovsk Research Institute- branch of the Scientific Research Center of the Russian Academy of Sciences in 2015-2021. The usual dump and non-dump, as well as fine mulching, zero and ridge tillage were studied. Autumn plowing at 20-22cm was taken as a control in the experiments. (PLN-4-35). Analysis of the infestation of fields at the time of harvest indicates that the annual plowing by 20-22 cm was distinguished by increased anti-weed efficiency, where the total number of weeds averaged 18.1 pcs./m2 with a weight of 24.9 g/m2. Of the ploughless options, the less clogged ones were those with a 20-22cm non-fallow treatment, with shallow comb-back treatment and comb-back with soil deepening, where the number of weeds remained at the control level. 17,9-18,4-18,1 pcs / m2, but there was an increase in the mass of weeds by 5-12%. Variants of fine processing, surface peeling with a stubble-laying machine and without autumn mechanical processing contributed to an increase in the weeding of crops compared to plowing, both in terms of quantity and above-ground mass of weeds by 10-12-15%, and 12-19%. It was noted that the formation of significantly larger biomass and the number of juvenile weeds was ensured on fertilized backgrounds, the harmfulness of perennial weeds decreased with an increase in the level of fertilization.

Research on identification method of tangerine peel year based on deep learning

Tangerine Peel has rich medicinal value, known as ' one kilogram of tangerine peel, one kilogram of gold '. However, the value of tangerine peels in different years is different, and there is no significant difference in the appearance of tangerine peels in different years. Identifying their authenticity has brought trouble to the industry. Generally speaking, the characteristics of tangerine peel can be identified through the texture, color and oil parcel points on the surface of tangerine peel. However, compared with the feature recognition of other Chinese medicinal materials, there is no significant difference in the shape of tangerine peel in different years, and the color is similar. Therefore, the feature extraction of tangerine peel is more complicated and the recognition is more difficult. The existing deep learning algorithms face great challenges in efficient and high accuracy recognition. In response to this challenge, this paper builds a new lightweight tangerine peel recognition algorithm TPRA (Tangerine Peel Recognition Algorithm) based on ResNet50. This algorithm uses a variety of methods to optimize the generalization ability of the model and improve the recognition accuracy. Firstly, TPRA adopts mixed data enhancement, including traditional data enhancement, deep convolution generation confrontation network DCGAN, and Mosaic data enhancement to enhance the richness of sample images in the dataset, reduced the data of each batch regularization (Batch Normal), and enhanced the performance of algorithm identification. Secondly, TPRA introduced the attention mechanism module CBAM (Convolutional Block Attention Module) combined with the cross stage partial network CSPNet (Cross Stage Partial Network) to propose an improved ResNet50 model, which adjusts the position of the maximum pooling layer and disassembles the large convolution kernel to effectively avoid overfitting. The experimental results showed that the accuracy of the algorithm can reach 98.8%, and the effect was better than that of Alexnet, VGG16 and Resnet50. TPRA provided a new method for the identification of peel years.

Garlic Peel Surface Modification and Fixed-Bed Column Investigations towards Crystal Violet Dye

Garlic peel, a low-cost agro-waste, was explored as an adsorbent for the remediation of wastewater containing the crystal violet (CV) cationic dye. The garlic peel was treated with NaOH at 1 : 1.5 ratios in order to modify the surface and increase its porosity. The surface-modified garlic peel was ground to a smaller size in order to increase its surface area and used as an adsorbent in the continuous column investigations. Column parameters such as bed height, flow rate, and initial concentration were optimised and found that optimal removal efficiency was achieved at 3 ml rate of flow, 3 cm column depth, and 100 mg l-1 initial concentration. The surface-modified garlic peel exhibited a higher loading capacity of 99.9 mg g-1 towards CV at optimised conditions. SEM investigations confirmed the surface modification and increase in porosity of the garlic peel. The column data was tending to fit well with Thomas and Yoon-Nelson’s models suggesting the scalability to an industrial level. Regeneration of MGP was successful with 0.01 M HCl solution. These results conclude that garlic peel is a potential agro-waste material that can be used to mitigate water pollution.

Development of biobased emulsions for postharvest citrus fruit preservation

Penicillium digitatum is the causal agent for citrus green mold which generates 90% of post-harvest losses in Mediterranean countries. The use of a green seaweed extract to fight this fungal pathogen could represent an ecofriendly alternative to chemical fungicides. We propose to formulate an aqueous extract from Ulva lactuca (8.3%) in an emulsion for the preventive treatment of oranges. New biobased emulsifiers, alkyl aconitates, were synthesized according to a green process and were characterized by their hydrophilic and lipophilic balance (HLB) and their critical micelle concentration (CMC). These mono-, di and tri-dodecyl aconitates (8%) were effective in stabilizing an oil-in-water emulsion including the natural U. lactuca extract. The viscosities of resulting emulsions helped to form a film on the orange surface. Several in vitro microbiological tests towards Penicillium digitatum showed interesting anti-fungal activities for the new ingredients, as well as for the resulting emulsions. In-vivo tests also confirmed that mono-, di- and tri-docedyl aconitates could contribute to limit the development of P. digitatum on peel surface. Thus, the compositions of two ecofriendly emulsions combining a natural extract and a biobased emulsifier seem adapted to improve oranges preservation.

Directly Electroplated Metallization on Flexible Substrates Based on Silver Nanowire Conductive Composite for Wearable Electronics

The metallization of flexible polymer surface is a necessary process to realize the electrical interconnection of insulating substrates, which is of great significance for the fabrication of flexible wearable electronics. Herein, a method for the fabrication of a metal/polymer composite is presented on the basis of a silver nanowire (AgNW) conductive composite by direct copper electroplating. A precoating was first coated on the polyethylene terephthalate (PET) substrate to form the interspace structures on the surface. AgNWs could just be embedded into these interspace structures by the means of coating to obtain excellent adhesion. Furthermore, these interspace structures were filled with deposited copper atoms, thus contributing to a strong interlock between the plated copper layer and the substrate. The obtained Cu/PET composites were subjected to morphological and mechanical characterizations to analyze the peeling strength, crystalline structure, and surface morphology of the plated copper layer. Experimental results show that the plated copper layer is dense and consistent with a maximum peel strength of 11 N cm–1. In addition, large scale of the Cu/PET (20 cm × 30 cm) composite with a thickness of 21 μm was fabricated by this method, and copper patterns were further fabricated using a conventional etching process. The fabricated copper patterns exhibit an outstanding electrical stability after 3000 times of a bending fatigue test, proving the excellent flexibility of the Cu/PET composite. In conclusion, this approach provides an insight into the design of metal/polymer composites addressing a significant potential application in flexible printed circuit, electrode, and antenna for wearable electronics.

High total Joule heat increases the risk of post-endoscopic submucosal dissection electrocoagulation syndrome after colorectal endoscopic submucosal dissection.

BACKGROUNDWe hypothesized that thermal damage accumulation during endoscopic submucosal dissection (ESD) causes the pathogenesis of post-ESD electrocoagulation syndrome (PECS).AIMTo determine the association between Joule heat and the onset of PECS.METHODSWe performed a retrospective cohort study in patients who underwent colorectal ESD from May 2013 to March 2021 in Japan. We developed a novel device that measures swift coagulation time with a sensor adjacent to the electrosurgical coagulation unit foot switch, which enabled us to calculate total Joule heat. PECS was defined as localized abdominal pain (visual analogue scale ≥ 30 mm during hospitalization or increased by ≥ 20 mm from the baseline) and fever (temperature ≥ 37.5 degrees or white blood cell count ≥ 10000 µ/L). Patients exposed to more or less than the median Joule heat value were assigned to the high and low Joule heat groups, respectively. Statistical analyses included Mann-Whitney U and chi-square tests and logistic regression and receiver operating characteristic curve (ROC) analyses.RESULTSWe evaluated 151 patients. The PECS incidence was 10.6% (16/151 cases), and all patients were followed conservatively and discharged without severe complications. In multivariate analysis, high Joule heat was an independent PECS risk factor. The area under the ROC curve showing the correlation between PECS and total Joule heat was high [0.788 (95% confidence interval: 0.666-0.909)].CONCLUSIONJoule heat accumulation in the gastrointestinal wall is involved in the onset of PECS. ESD-related thermal damage to the peeled mucosal surface is probably a major component of the mechanism underlying PECS.

Transcriptome and Metabolome Comparison of Smooth and Rough Citrus limon L. Peels Grown on Same Trees and Harvested in Different Seasons.

Background: Farmers harvest two batches fruits of Lemons (Citrus limon L. Burm. f.) i.e., spring flowering fruit and autumn flowering fruit in dry-hot valley in Yunnan, China. Regular lemons harvested in autumn have smooth skin. However, lemons harvested in spring have rough skin, which makes them less attractive to customers. Furthermore, the rough skin causes a reduction in commodity value and economical losses to farmers. This is a preliminary study that investigates the key transcriptomic and metabolomic differences in peels of lemon fruits (variety Yuning no. 1) harvested 30, 60, 90, 120, and 150 days after flowering from the same trees in different seasons.Results: We identified 5,792, 4,001, 3,148, and 5,287 differentially expressed genes (DEGs) between smooth peel (C) and rough peel (D) 60, 90, 120, and 150 days after flowering, respectively. A total of 1,193 metabolites differentially accumulated (DAM) between D and C. The DEGs and DAMs were enriched in the mitogen-activated protein kinase (MAPK) and plant hormone signaling, terpenoid biosynthesis, flavonoid, and phenylalanine biosynthesis, and ribosome pathways. Predominantly, in the early stages, phytohormonal regulation and signaling were the main driving force for changes in peel surface. Changes in the expression of genes associated with asymmetric cell division were also an important observation. The biosynthesis of terpenoids was possibly reduced in rough peels, while the exclusive expression of cell wall synthesis-related genes could be a possible reason for the thick peel of the rough-skinned lemons. Additionally, cell division, cell number, hypocotyl growth, accumulation of fatty acids, lignans and coumarins- related gene expression, and metabolite accumulation changes were major observations.Conclusion: The rough peels fruit (autumn flowering fruit) and smooth peels fruit (spring flowering fruit) matured on the same trees are possibly due to the differential regulation of asymmetric cell division, cell number regulation, and randomization of hypocotyl growth related genes and the accumulation of terpenoids, flavonoids, fatty acids, lignans, and coumarins. The preliminary results of this study are important for increasing the understanding of peel roughness in lemon and other citrus species.

Evaluating the response of insecticides and fungicides for rind blemishes management in Kinnow mandarin (Citrus nobilis Lour × Citrus deliciosa Tenora) fruits caused by biotic factors

Kinnow mandarin being produced in Pakistan faces different quality issues ending up in poor rind quality bearing blemishes on the peel. The main reason behind quality issues is inadequate production management including unoptimized production technology with an inappropriate spray schedule of insecticides and fungicides. Major blemishes found on the surface of fruit are biotic in nature (diseases and insects) and generally appear during the early 8-12 weeks of fruit setting. The objective of this study was to optimize insecticides and fungicides to manage rind blemishes in ‘Kinnow’ mandarin fruits caused by biotic factors. The present study was conducted during 2017-2018; there were four kinds of pesticides such as Actara (Thiamethoxam) or Confidor (Imidacloprid) and Nativo (Tebuconazole and Trifloxystrobin) or Topsin M (Thiophanate-methyl) sprayed to the trees at onset of fruit setting. The extent and nature of blemishes related to diseases and insects were significantly reduced after the spray of 0.3 g L-1 Nativo, 1.5 ml L-1 Confidor as compared to the application of Actara (0.24 g L-1 water) and Topsin M (2 g L-1 water), while the higher extent of blemishes was recorded in control block. Surface smoothness and peel colour of fruits showed significant improvement in sprayed trees compared to control. Likewise, preharvest sprays reduced the post-bloom and commercial fruit drop, resulting in a high yield per tree. However, the preharvest sprays showed a non-significant effect on organoleptic quality and biochemical attributes of ‘Kinnow’ fruit. Conclusively, the combination of Confidor (1.5 ml L-1 water) and Nativo (0.3 g L-1 water) sprays at fruit setting stage could be helpful in managing biotic blemishes in ‘Kinnow’ mandarin fruits resulted in an increased proportion of A-grade quality fruits in final pack out.

Classification of bananas during ripening using peel roughness analysis—An application of atomic force microscopy to food process

AbstractTo monitor banana surface (peel) roughness changes during ripening treatment, atomic force microscopy (AFM) as a novel and emerging technique was used in this study. The roughness of banana peel was studied using the arithmetic mean between peaks and troughs (Ra) and the root‐mean‐square roughness (Rq). It was concluded that with changing the ripening stages, the behavior of the roughness changes significantly. With advancing fruit ripening, the extending of the epicarp and the decrease of the surface (peel) roughness were found due to enlarging of fruit volume. The highest mean roughness was found to be at stage 1, Ra = 8.25 and Rq = 9.65 nm. Based on two‐dimensional profile results, the surface (peel) roughness was affected strongly by studied different ripening stages. It was concluded that the peak values in the ripple profiles become smaller with advancing fruit ripening. However, the effects of noise in the profiles appeared to increase. So, in all the initial stages of banana fruit ripening, the noise was found to be minimal. Consequently, the AFM technique was found to be a promising tool for quantification of the peel roughness or glossiness and also could help in the quality control of banana fruit on the nanoscale.

Effects of processing parameters on the fracture behaviour of cold roll bonded and accumulative roll bonded Al–Cu lamellar composites

Al–Cu composites were fabricated by cold roll bonding (CRB) and accumulative roll bonding (ARB) processes. The effects of different parameters were investigated on the failure mechanism of the composites. A scanning electron microscope (SEM) and an optical microscope (OM) were used to characterise the microstructures of the resulting composites. The peeled surfaces of the CRBed material revealed that micro-cracks were formed almost perpendicular to the rolling direction and caused the premature failure of the bonding during the peeling test. Also, tensile, microhardness and shear punch tests were conducted on the Al–Cu composites produced under different conditions. Failure analysis of the non-heat-treated composites revealed that the layers separated from the middle of ARBed specimens. However, these centre-line separations were alleviated in composites subjected to heat treatment, even though the initiation of inter-lamellar micro-cracks were observed due to the formation of intermetallic compounds for heat-treated specimens.

Identity, Synthesis, and Cytotoxicity of Forchlorfenuron Metabolites in Kiwifruit.

Forchlorfenuron (CPPU) is a plant growth regulator widely used in kiwifruit production. Although research on the toxicological and environmental effects of CPPU is well-established, the nature and toxicological properties of its metabolites are much less well-known. Using high resolution mass spectrometry and nuclear magnetic resonance, the CPPU previously unidentified metabolites in Xuxiang and Jinyan kiwifruit were identified as N-(2-chloro-4-pyridinyl)-N'-(2-hydroxy-4-methoxyphenyl)-urea (metabolite 1) and N-phenyl-N'-4-pyridinylurea (metabolite 2, CAS: 1932-35-0). Their structures were confirmed by synthesis (metabolite 1) and by comparison with a commercial standard (metabolite 2). Quantitative studies demonstrate that CPPU and its metabolites are mainly retained in the kiwifruit peel, while the content is dependent on the nature of the peel surface, with the smoother peel of Jinyan kiwifruit retaining smaller amounts of the compound. Cell viability experiments in Caco2 and Lo2 cells show that the metabolites may have a lower cytotoxicity compared to the parent compound CPPU.