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This study encompasses the evaluation of mechanical, and electrical properties of PVA-MWCNT-based thin film composites (TFC) in the presence of Li2SO4. The PVA-MWCNT-based TFC is obtained using solvent casting technique while the characterization is carried out through thermogravimetric analysis (TGA), Fourier transform infrared (FTIR), X-ray diffractometry (XRD), and scanning electron microscopy (SEM) techniques. Tensile testing techniques is used for measuring mechanical properties such as elasticity, tensile strength, elongation, hardness and fracture toughness of the PVA-MWCNT-based TFC. Additionally, the tensile strength has increased from 47.8 N.m− 2 to 80.0 N.m− 2, whereas elongation at break has improved from 80.8 to 124.2 mm. Ac Impedance spectroscopy is applied to study the electrical properties of PVA-MWCNT-based TFC. Thermal studies via TGA shows that the addition of lithium salt has positive effect on the thermal stability of the based PVA-MWCNT-based TFC. The XRD results shows a decrease of crystallinity of PVA-MWCNTs-based TFC on the addition of lithium salts (Li2SO4). Subsequently, a smooth surface morphology of all the composites, bearing no holes or roughness in SEM micrograph confirmed a well dispersion of MWCNTs and Li2SO4 salt in PVA matrix. During Mechanical study, an increase in the value of young modulus, tensile strength, and elongation break are observed with the addition lithium salt. Ac Impedance results show an increase in conductivity of PVA-MWCNTs-based TFC. The dielectric constant, dielectric loss and dielectric tangent loss properties of the PVA-MWCNT-based TFC also enhanced with the increase in lithium salts. [ABSTRACT FROM AUTHOR]

Pre-harvest application of zinc sulphate enhanced growth and promotes post-harvest quality of fruits during storage. Plum fruit exhibits climacteric behavior and its quality characteristics depending on the harvest stage. The present research study entitles "Influence of zinc on pre and postharvest quality of plum" was conducted at Horticulture Research Farm and postharvest laboratory Department of Horticulture, The University of Agriculture Peshawar. Plum fruits are perishable and cannot be stored for long periods. Plum fruit exhibits climacteric behavior and its quality characteristics depending on the harvest stage. The effect of all experimental treatments result was significant for all studied growth attributes when compared with control. Zn at the rate of 1.1 kg ha-1applied 15 days after fruit set increased leaf protein content (6.53 %), the total number of fruits plant-1 (916). Among application stages, Zn sprayed 15 days after fruit set increased leaf protein content (6.70 %), total number of fruits plant-1 (932). Various attributes studied for storage du-ration of plum fruit were significantly affected by zinc concentration less weight loss (11.91%), TSS (13.76 °Brix) were recorded with fruit plant sprayed with zinc sulphate @ 1.1 kg ha-1. The result for various zinc application stages less weight loss (12.75%), TSS (14.18 °Brix) were recorded with fruit plant sprayed 15 days after fruit set. Storage duration means showed lowest TSS (8.99 °Brix) respectively. It is concluded that plum tree could be sprayed with 1.1 kg ha-1 zinc sulfate 15 days of fruit set to improve better yield and prolong the shelf life of plums up to 30 days under low temperature (10±2 °C and RH 80-90%). [ABSTRACT FROM AUTHOR]

The experiment was designed to investigate "the influence of storage temperature on mango fruit quality during simulated marketing" by storing the fruit at 5, 10 and 15 ± 1 ℃ for 5, 10, 15, 20, 25 and 30 days and analyzing the physico-chemical attributes of mango after three days simulated marketing. The experiment was laid out in Completely Randomized design with three repeats. With the increase in pre-simulation storage time weight loss, fruit juice pH, chilling injury score and ion leakage increased whereas, the ascorbic acid decreased during simulated marketing. The means for temperatures revealed that weight loss, ascorbic acid and chilling injury score were the highest in fruits exposed to 5 ± 1 ℃ before simulated marketing. Initially weight loss was lower in fruits exposed to 5 ± 1 ℃ but the increasing exposure duration resulted in higher weight loss than 10 and 15 ± 1 ℃. Similarly, the ascorbic was higher at 5 ± 1 ℃ but declined rapidly with 25 days exposure to 5 ± 1 ℃. Fruit juice pH increased with the increase in storage temperature. Ion leakage remained the least in fruits exposed to 10 ± 1 ℃ before simulation that was the highest at 5 ± 1 ℃. Ion leakage was initially the lowest at 5 ± 1 ℃ but after 20 days it reached to the highest level. During simulated marketing, chilling injury (CI) occurs after 10 days in fruits stored at 5 ± 1 ℃ therefore, if proper technologies for alleviation of CI are not available, mango cv. "Langra" fruit may be stored at 10 ± 1 ℃. [ABSTRACT FROM AUTHOR]

Calcium application maintains cell turgor, membrane integrity, tissue firmness and delays membrane lipid catabolism thus extending storage life of fresh fruits. The objective of this experiment was to assess the effect of calcium sources (Calcium chloride, calcium gluconate, Calcium lactate and calcium sulphate) at various concentration (0, 0.25, 0.50 and 0.75) and stored at low temperature (10± 2°C) and ambient temperature (32±2°C) on the quality related attributes of tomato fruit. The results of the study showed that higher fruit firmness (2.25 kg cm-2), percent acidity (0.34%), ascorbic acid content (9.90 mg 100g-1), non reducing sugars (1.58%), minimum physiological weight loss (20.18%), TSS (4.99 °Brix) and reducing sugars (3.53%) was recorded in fruits stored at low temperature, as compared to fruits stored at ambient temperature. Calcium concentration at 0.75% significantly retained fruit firmness (2.60 kg cm-2), percent acidity (0.38%), ascorbic acid content (9.68 mg 100g-1), non reducing sugars (1.74%) and reduced the physiological weight loss (14.33%) and TSS (5.03 °Brix), while reducing sugars (3.26%) were recorded as minimum in tomatoes supplied with 0.5% calcium concentration. Regarding the means for calcium sources, highest value of fruit firmness (2.82 kg cm-2), percent acidity (0.44%), ascorbic acid content (13.52 mg 100g-1), non reducing sugars (2.34%), minimum physiological weight loss (12.72%), TSS (4.96 °Brix), and reducing sugars (3.10%), were retained in fruits treated with CaCl2. Therefore, it is concluded that CaCl2 at high concentration and low temperature should be used for tomato fruit quality and increased shelf life. [ABSTRACT FROM AUTHOR]