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The rising population is increasing food demand, yet actual crop production is limited by the poor efficiency of classical fertilizers. In particular, only about 40–60% of fertilizer nitrogen, 15–20% of phosphorus and 50–60% of potassium are used by crop plants, the rest ending polluting the environment. Nanofertilizers are promising alternatives. Here, we review plant nutrients, synthesis of zinc oxide nanoparticles, encapsulation of nanoparticles in fertilizers, and effect on plants.

Polymer materials are vulnerable to damages, failures, and degradations, making them economically unreliable. Self-healing polymers, on the other hand, are multifunctional materials with superior properties of autonomic recovery from physical damages. These materials are suitable for biomedical and tissue engineering in terms of cost and durability. Schiff base linkages-based polymer materials are one of the robust techniques owing to their simple self-healing mechanism. These are dynamic reversible covalent bonds, easy to fabricate at mild conditions, and can self-reintegrate after network disruption at physiological conditions making them distinguished. Here we review self-healing polymer materials based on Schiff base bonds. We discuss the Schiff base bond formation between polymeric networks, which explains the self-healing phenomenon. These bonds have induced 100% recovery in optimal cases.

The research encompasses on a comparative study of biodegradable membranes based on poly(vinyl alcohol) (PVA), starch (St), graphene oxide (GO) and reduced graphene oxide (rGO) for food packaging application. Four different concentrations, i.e., 10, 20, 30 and 40 mg, of GO and rGO were incorporated in membranes using in situ and ex situ reduction technique. The aim was to enhance the antibacterial and mechanical properties of PVA/St membranes. PVA/St membranes having 20 mg of in situ reduced graphene oxide (PVA/St/IrGO20) exhibited an exceptional tensile strength of 22.719 MPa and outstanding antibacterial activity, i.e., 38.89 ± 0.23 mm and 37.52 ± 0.41 mm, against Escherichia coli and Methicillin-resistant Staphylococcus aureus, respectively. The membranes were also analyzed by scanning electron microscopy (SEM), X-ray diffraction, Fourier transform infrared spectroscopy (FTIR) and thermogravimetric analysis (TGA). SEM results revealed the dense morphology for all membranes. FTIR results displayed the successful synthesis of GO, rGO and nanocomposite membranes. The TGA showed that IrGO membranes were more stable as compared to neat and graphene oxide membranes. Moreover, the membranes degraded completely after being buried in the soil. Among all the synthesized membranes, PVA/St/IrGO20 and PVA/St/XrGO10 (PVA/St containing 10 mg ex situ reduced GO) exhibited excellent barrier against water vapor and oxygen transmission. Therefore, they prolonged the shelf life of packed gooseberries as compared to all formulated membranes.

Engineered materials are crucial for the higher efficiency of supercapacitors. Current work presents roughly shaped spherical NiFe2O4 nanoparticles dispersed in the SiO2 matrix NiFe2O4/SiO2 as a newfangled electrode material for supercapacitors with remarkable performance. Designing the NiFe2O4/SiO2 nanostructure with a sol-gel method followed by the Stober method to grow silica has instigated NiFe2O4/SiO2 as dynamic material with higher electrochemical activity. Physicochemical aspects of NiFe2O4/SiO2 nanostructures are evaluated using Fourier-transform infrared spectroscopy, X-ray diffraction, scanning electron microscopy, and transmission electron microscopy analysis. The electrochemical activity is evaluated by cyclic voltammetry (CV) and galvanostatic charge-discharge (GCD) representing the comparable efficiency and reversibility of the electrode materials. The prepared electrode shows a capacitance of 925 F/g (154.1 mAh/g or 555 C/g) at 1 A/g, with 95.5% capacitance retention after 5000 cycles at 20 mA/cm2. The improved electrochemical performance of the NiFe2O4/SiO2 electrode can be subjected to prompt diffusion process provided by NiFe2O4/SiO2 and enhanced redox reactions owing to the high surface area. The mentioned features decrease the total impedance of the electrodes as suggested by electrochemical impedance spectroscopy (EIS).

Nanocomposite membranes promoted by mimic enzyme was developed and optimized for biogas upgrading at moderately high pressure applications up to 15 bar. Zn based mimic enzyme (Zn-cyclen) was synthesized. Different concentrations of selected mimic enzyme were added in nanocomposite membranes containing 1% crystalline nanocellulose (CNC) and 2% polyvinyl alcohol (PVA). The addition of mimic enzyme improved separation performance. The optimal results were obtained with 5 µmol/g addition of mimic enzyme at 10 pH. Furthermore, the addition of mimic enzyme showed abrupt change in moisture uptake ability and the maximum values were found for addition of 0.005wt% of mimic enzyme loading. Permeation testing showed that presence of moisture content plays important role in the activation of mimic enzyme. Furthermore, at high pH values mimic enzyme showed improved CO2 hydration rates. SEM results exhibited smooth morphology and no significant different in membrane thickness with increase in the mimic enzyme concentration. Moreover, the decline in membrane performance was observed with increasing pressure up to 15 bar. CNC/PVA based membranes with optimal loading of mimic enzyme showed significantly high separation than pure PVA membrane; a permeance of 0.34 [m3(STP)/m2 bar hr] and selectivity of 42.

An active and intelligent starch-based biodegradable food packaging system is developed in this work. The growing environmental protection concerns have motivated researchers to look for biodegradable yet sustainable products for food packaging. The packaging is able to resist against undesirable bacterial attack and color-change response due to pH change in food. Polyvinyl alcohol and starch are cross-linked with Glutaraldehyde to improve their mechanical strength. Propolis Extract (PE) and anthocyanin (ATH) were added as an active and intelligent material, respectively. Different film formulations were prepared by varying concentration of PE. All film formulations were characterized by SEM, FTIR and XRD. The results proved good compatibility of the film mixture. The mechanical strength and other physical properties like water vapor transmission rate, moisture retention capability, swelling degree and biological leaching ability were investigated. Films containing 20% PE showed the best results alongside maximum mechanical strength of 15.9 MPa. Furthermore, the same formulation has shown maximum zone of inhibition of 25 mm and 20 mm against E. Coli and MRSA, respectively. Moreover, there was a clear color-change response when films were immersed in different pH solutions ranging from 1 to 14. Finally, to validate the potential application of prepared film formulations, films were tested on pasteurized milk and a color-change response is observed along with the anti-bacterial activity. Hence, this active and intelligent food packaging system is capable of inhibiting and alerting food spoilage.[Formula: see text]

© 2020 Hydrogen Energy Publications LLC There are still gaps in the field of reference electrode that is needed to assist electrolysis in high temperature electrolytes (e.g. molten hydroxides) for H2 gas production. This research aims to fill the gaps by preparing Ni/Ni(OH)2 reference electrode and more importantly testing its effectiveness against important performance factors including; ion conducting membrane (e.g. mullite tubes), internal electrolyte composition, working temperature and electrochemical control (e.g. potential scan rate). Then, this reference electrode was used to study the electrocatalytic activity various cheaper working electrode materials including; stainless steel (St.st), Ni, Mo and Ag in comparison with Pt by the means of chronoamperometry and voltammetry. The effect of introducing steam into electrolyte (eutectic mixture of NaOH and KOH) on the electrocatalytic activity of these working electrodes was also studied. It was observed that the potential of hydrogen evolution with different working electrodes followed an order as; Pt > Ni > St. st > Ag > Mo (positive to negative). The performance of each working electrode was confirmed through chronoamperometry for hydrogen evolution at a constant potential of −0.7 V. It was also found in cyclic voltammetry and confirmed by chronoamperometry that the introduction of steam was apparent as increasing the current density at cathodic limit for hydrogen evolution. This study could help to develop non-precious metal electrodes for the production of hydrogen fuel. In future, there will be a potential in the threshold concentration of steam for H2 gas production.

Wound care has come through various trials and errors with primitive cultures applying old age techniques and knowledge. Recent research has shown that the moist environment promotes wound healing than the dry. In the present research, hydrogel membranes were fabricated by esterification of polyvinyl alcohol (PVA) with starch and glutaraldehyde as a cross-linker. The essential oils (clove oil, Oregano oil and tea tree oil) have been incorporated in PVA/Starch based hydrogel membranes. The aim was to achieve optimized anti-bacterial activity and mechanical strength. The anti-bacterial testing was performed using the disc diffusion method. The maximum antibacterial activity for fabricated hydrogels was attained by addition of 0.1 mL clove oil in PVA/Starch hydrogel was 39 ± 0.57 mm and 37 ± 0.29 mm for MRSA and E. coli, respectively. The FTIR results presented the occurrence of –OH group in hydrogel membrane. The SEM results showed around dense nature of membranes with having an antibacterial agent in it or not. Mechanical examination of hydrogel membranes presented suitable tensile strength of 19.36 MPa for 0.1 mL Clove oil. Furthermore, water vapour transmission rate (WVTR) and moisture retention capability (MRC) for 0.1 mL clove oil was 36.22 g/m2h and 95.50%, respectively. The experimental conclusion nominated that fabricated hydrogel articulates good antibacterial, mechanical and physical properties that it could be used in wound dressing applications. The best results were obtained for clove oil using 0.1 mL as an antibacterial agent.

In this work, the effect of Zn-cyclen mimic enzyme on the properties of poly(vinyl alcohol)/cellulose nanocrystals (PVA/CNC) nanocomposite membranes have been studied at three different relative humilities (0%RH, 53%RH and 93%RH). Different amounts of mimic enzyme were incorporated, and membranes were prepared by solution casting. The fabricated nanocomposite films were characterized by X-ray Diffraction, Fourier Transform Infrared Spectroscopy and Scanning Electron Microscopy. The results revealed good interfacial interactions between the constituents. The membranes showed enhanced uptake of moisture, with increasing mimic enzyme concentration as well as humidity. The membranes demonstrated the ability to uptake moisture for almost 4 days. The mechanical properties showed an opposite trend as expected. Tensile strength, tensile modulus and dynamic mechanical properties declined with increase in humidity along with mimic enzyme amount. The highest elastic modulus i.e. 33 MPa was found at the lowest humidity i.e. 0%RH for the pure PVA membrane. Similarly, the maximum tensile strength of 118 MPa was found at the similar conditions for the same formulation. The obtained results suggested the potential application of PVA/CNC and mimic enzyme membranes in CO2 separation.

Presently, about 200 million tons of urea fertilizer is produced worldwide to meet supply and demand. However, a quarter of the urea applied to soils is lost to the environment due to poor efficien...

Slow release urea has been widely tested in recent past as an effective method to enhance the crop productivity with fewer environmental concerns. However, very few research studies have been performed using micronutrients as a source of slow release of urea nitrogen. A laboratory and field study were carried out to check the agronomic effects of zinc oxide nanoparticles and its bulk salt coatings on urea prills on wheat (Triticum aestivum L.). Different concentrations of zinc oxide nanoparticles (0.25, 0.5 and 4% elemental zinc) were coated on urea prills to slow down the release rate. Bulk zinc oxide salt (ZnO) with similar concentrations was also used in parallel to make a comparison between nano and bulk salt. The SEM of zinc oxide nanoparticles clearly depicted zinc oxide nanoparticles size within a range of 50-90 nm. The XRD and FTIR spectrums also showed its characteristics peak at designated positions. Field study revealed than 0.5% zinc oxide nanoparticles coated urea boosted the crop growth and yield in comparison to the bulk zinc oxide coated urea having similar zinc concentrations, i.e., 0.25%, 0.5% and 4% elemental zinc. The plant parameters like plant height, root length, root volume, grain yield and dry matter weight were significantly increased due to application of zinc oxide nanoparticles.

Membrane-based gas separation has a great potential for reducing environmentally hazardous carbon dioxide (CO

Biogas up-gradation is a useful method to control CO

Low nitrogen (N) use efficiency from urea fertilizers due to environmental losses results in high cost of fertilizers for agricultural productions. Coating of urea with biodegradable polymers makes them effective for control and efficient N release. In this study, starch and polyvinyl alcohol (PVA) were used in combination with acrylic acid (AA), citric acid (CA) and maleic acid (MA) for the coating of urea prills. Different formulations of the coating were prepared and applied on urea prills such as urea coated with starch (10%) and PVA (5%) with acrylic acid: 2, 4 and 6% (USP-A2, USP-A4, USP-A6), with citric acid: 2, 4 and 6% (USP-C2, USP-C4, USP-C6), and with maleic acid: 2, 4 and 6% (USP-M2, USP-M4, USP-M6). After urea coating in fluidized bed coater, all uncoated and coated urea samples were characterized by scanning electron spectroscopy (SEM), Fourier transform infrared spectroscopy (FTIR), X-ray diffraction (XRD), crushing strength and UV-Vis spectroscopy. The morphological and XRD analysis indicated that a new uniform coating with no new phase transformation occurred. Among all urea coated samples, USP-A2 and USP-C2 showed the highest crushing strengths: 12.08 and 13.67 N with nitrogen release efficiency of 70.10 and 50.74% respectively. All coated urea samples improved the spinach plants’ foliage yield, chlorophyll content, N-uptake and apparent nitrogen recovery (ANR) than uncoated urea and control plants. However, USP-A2 and USP-C2 provided promising results among all coated samples with dry foliage yield (2208 ± 92 and 2428 ± 83 kg/ha), chlorophyll (34 ± 0.6 and 34 ± 0.4 mg/g), N-uptake (88 ± 4 and 95 ± 6 kg/ha) and ANR (59 ± 4 and 67 ± 6%). Therefore, urea prills coated with a combination of biodegradable polymers can be a better choice for the farmers to enhance agronomical productions by controlling the fertilizer nutrient release rate.

A ground-breaking and soft nanomaterial, namely graphitic carbon nitride (g-C3N4) has gained importance as two-dimensional filler in polymeric membranes. In this research, g-C3N4 was synthesized by “thermal oxidation etching process”, employing melamine as a precursor. The porous nanosheets were characterized by SEM, XRD and FTIR. g-C3N4 nanosheets showed remarkable thermal stability up to 620 °C. The PVA starch nanocomposite membranes were fabricated with varying amounts of g-C3N4. Owing to strong interactions between g-C3N4, and polymers, the composite membranes showed exceptional thermal and mechanical stability and resist to degrade in various mediums including water, saline and blood. The hybrid membranes showed remarkable swelling abilities up to 96 h. Moreover, g-C3N4 enhanced the hydrophilicity, consequently, moisture retention capability and water vapor transmission were improved. XRD and SEM results revealed the proper dispersion of g-C3N4 into the polymeric matrix. The results suggested that prepared hybrid PVA/St/g-C3N4 membranes could be used as wound dressings.

To address nitrogen (N)-related environmental pollution, development of an economical, slow-release urea fertilizer is the need of the hour. A study was conducted on the reduction of nitrogen relea...

High moisture uptake and excellent mechanical properties of cellulose nano-fibril (CNF) make it an interesting material to use as an additive in facilitated transport membranes. The objective of th...

Thermoplastic starch (TPS) is a potential alternative to non-degradable plastics. However, the hydrophilic nature and relatively weak mechanical properties is a major hurdle to its commercial application. In this study, Ultra-violet (UV) irradiation based cross-linking was investigated for its effect on the mechanical properties of TPS films plasticized by boric acid, and glycerol. Spray dried amorphous powder was compressed to obtained TPS films. All the samples were amorphous under dry conditions (RH0%) while retro-gradation was resisted at the relative humidity (RH) of50% and 100% for all the films. The concentration of the plasticizers influenced the moisture uptake ability of TPS films. UV irradiation showed no effect on the crystallinity of TPS films. However, it enhanced the mechanical strength and lessened the solubility and degree of swelling. Boric acid plasticized and co-plasticized samples revealed improved mechanical properties before and after UV irradiation compared to glycerol but showed more moisture sensitivity before cross-linking. The UV irradiated starch with 30% boric acid as plasticizer (30BA.UV.PS) showed highest tensile strength (4.28 MPa) among all the samples at 50% relative humidity. Moreover, the strain at break of the same sample decreased from 12.53% to 9.12% at 50% relative humidity.

Membranes with zeolites are encouraging for performing blood dialysis because zeolites can eliminate uremic toxins through molecular sieving. Although the addition of various pore-gen and adsorbent in the membrane can certainly impact the membrane production along with creatinine adsorption, however, it is not directed which pore-gen along with zeolite leads to better performance. The research was aimed at reducing the adsorption of protein-bound and uremic toxins by using mordenite zeolite as an adsorbent while polyethylene glycol and cellulose acetate as a pore generating agent. Membranes were cast by a phase-inversion technique which is cheap and easy to handle as compared to the electro-spinning technique. Through this strategy, the ability to adsorb creatinine and solute rejection percentage were measured and compared against the pristine PSU, when only PEG was used as a pore-modifier and when PEG along with CA was used as a pore-modifier along with a different concentration of zeolite. The experiments revealed that PEG membranes can give a better solute rejection percentage (93%) but with a low creatinine adsorption capacity that is 7654 μg/g and low bio-compatibility (PRT 392 s, HR 0.46%). However, PEG/CA membranes give maximum creatinine adsorption that is 9643 μg/g and also better bio-compatibility (PRT 490 s, HR 0.37%) but with a low BSA rejection (72%) as compared to the pristine PSU and PEG membranes. The present study finds that the concentration of mordenite zeolite affects the membrane performance because its entrapment and large pore size of the membrane decreases solute rejection but increases creatinine uptake level along with the better bio-compatibility.

Low nitrogen (N) utilization efficiency due to environmental N losses from fertilizers results in high-cost on-farm production. Urea coating with biodegradable polymers can prevent these losses by controlling the N release of fertilizers. We calculated N release kinetics of coated granular with various biodegradable polymeric materials and its impact on spinach yield and N uptake. Different formulations were used, (i) G-1: 10% starch + 5% polyvinyl alcohol (PVA) + 5% molasses, (ii) G-2: 10% starch + 5% PVA + 5% paraffin wax (PW), (iii) G-3: 5% gelatin + 10% gum arabic + 5% PW, (iv) G-4: 5% molasses + 5% gelatin + 10% gum arabic, to coat urea using a fluidized bed coater. The morphological and X-ray diffraction (XRD) analyses indicated that a uniform coating layer with no new phase formation occurred. In the G-2 treatment, maximum crushing strength (72.9 N) was achieved with a slowed-down N release rate and increased efficiency of 31%. This resulted in increased spinach dry foliage yield (47%), N uptake (60%) and apparent N recovery (ANR: 130%) from G-2 compared to uncoated urea (G-0). Therefore, coating granular urea with biodegradable polymers is a good choice to slower down the N release rate and enhances the crop yield and N utilization efficiency from urea.

The application of urea-based fertilizers in developing countries has gained significant momentum over time. urea usage is to meet demand and supply gap of food resources as world population is increasing at a fast pace. urea contains largest content of nitrogen (46%) among all the solid nitrogenous fertilizers. However, main drawback of urea is its higher dissolution rate. After soil application, most of urea nitrogen is lost through a leaching, runoff, nitrification-denitrification and ammonia volatilization. To tackle urea related environmental pollution, development of slow-release urea fertilizer is a need of the hour and this would also increase product use efficiency in terms of crop productivity and its N uptake. We studied the usage of polymeric materials in combination with inorganic substances like sulfur and plaster of Paris as effective and biodegradable coating substances for urea prills. For coating on urea prills, fluidized bed coater was used whereas paraffin wax and molasses were used as binding agents. The urea was coated with four different formulations, i.e., C-1: PVA 5% + plaster of Paris 10% + sulfur 5% + paraffin wax 2%, C-2: PVA 5% + starch 10% + sulfur 5% + paraffin wax 2%, C-3: gelatin 5% + plaster of Paris 10% + sulfur 5% + paraffin wax 2% and C-4: PVA 5% + starch 10% + sulfur 5% + paraffin wax 2.5% + molasses 2.5%. Each formulation along with uncoated urea prills (C-0) were evaluated for characterization and N release kinetics. All the formulations along with uncoated urea were applied to spinach crop in pot experiment. A control (No N: untreated) was also kept. Spinach biomass yield and N uptake were determined. The formulation C-1 yielded highest urea-N release efficiency and spinach N uptake of6.87% and 1.93 g N/pot, respectively. Themodified Schwarz and Sinclair formula gave the excellent representation of release of nutrient-N from coated urea prills. It is concluded that coating urea prills with organic and inorganic blends is better option to slow down N release kinetics and improve spinach productivity. Therefore, by using coated fertilizers, farmers can improve agro-environmental value of urea, worldwide.

Hydrogel is the most emblematic soft material which possesses significantly tunable and programmable characteristics. Polymer hydrogels possess significant advantages including, biocompatible, simple, reliable and low cost. Therefore, research on the development of hydrogel for biomedical applications has been grown intensely. However, hydrogel development is challenging and required significant effort before the application at an industrial scale. Therefore, the current work focused on evaluating recent trends and issues with hydrogel development for biomedical applications. In addition, the hydrogel's development methodology, physicochemical properties, and biomedical applications are evaluated and benchmarked against the reported literature. Later, biomedical applications of the nano-cellulose-based hydrogel are considered and critically discussed. Based on a detailed review, it has been found that the surface energy, intermolecular interactions, and interactions of hydrogel adhesion forces are major challenges that contribute to the development of hydrogel. In addition, compared to other hydrogels, nanocellulose hydrogels demonstrated higher potential for drug delivery, 3D cell culture, diagnostics, tissue engineering, tissue therapies and gene therapies. Overall, nanocellulose hydrogel has the potential for commercialization for different biomedical applications.

The effect of the viscosity of the casting suspension on membrane morphology and thickness has been investigated for polyvinyl alcohol (PVA)/crystalline nanocellulose (CNC) nanocomposite membranes used for CO 2 /CH 4 separation. Different concentrations of CNC suspended in dissolved PVA affected the viscosities of resulting suspensions. A methodology was developed to make equal viscosity suspensions with variable CNC content. SEM micrographs show that by increasing the concentration of CNC in PVA, the thickness of the selective layer increased. However, equal thickness was achieved by water dilution for viscosity adjustment. The overall objective of this work was to find the real optimum concentration of CNC in PVA for CO 2 /CH 4 separation independent of the membrane thickness. Furthermore, the effect of the relative humidity (RH) and feed pressure on the selectivity and permeability of the membranes were also investigated as part of this study. For 1.5% CNC in PVA with pH 9 in the casting suspension, tested at feed pressure of 5 bar, CO 2 /CH 4 selectivity was up to 39 and the achieved permeance was 0.27 m 3 (STP)/(m 2 h bar). Above this concentration of CNC, the CO 2 permeation and selectivity decreased. It was also observed that increasing pressure caused a decrease in the performance of the membranes for CO 2 capture in terms of both permeation and selectivity. Moreover, increasing RH causes increasing in CO 2 permeation and selectivity.

Biogas can be used as an alternative energy source in place of conventional fossil fuels. However, for this to happen, it is necessary to optimize biogas production as well as improve the biogas quality. Crystalline nanocellulose (CNC) has excellent mechanical properties as well as a high moisture uptake ability. These properties make CNC a promising candidate to be used as an additive in polyvinyl alcohol (PVA)-facilitated transport membranes (FTMs). The overall objective of this work is to develop CNC/PVA nanocomposite membranes for enhancing the biogas quality through CO2 capture. The effects of CNC concentration and the pH of the casting solution are investigated to optimize CO2/CH4 separation. Membrane characterization shows that the addition of CNC affects the degree of swelling, crystallinity and thickness of the resulting membranes, while permeation testing showed that the permeance and selectivity for CO2 increased with the addition of CNC. Membranes produced with 1% CNC and a casting suspension at pH 10 gave the best results under the given set of conditions. The maximum permeance achieved by the formulated nanocomposite membranes was 0.29 m3(STP)/(m2-h-bar), while the selectivity of CO2 over CH4 was 43. It was also observed that increasing the feed gas pressure deteriorated the membrane performance.

This study focuses on the thermal, morphological and physical properties of spray-dried chicory root inulin using a thermogravimetric analyzer, environmental scanning electron microscopy, X-ray diffractogram and modulated differential scanning calorimetry. Different spray-drying conditions were investigated by varying inlet temperature, outlet temperature and aspirator speed. The starting material was semicrystalline. A feed temperature of 95°C was employed, which produced a completely transparent solution for spray drying. At that particular temperature, the powder samples obtained were entirely amorphous and morphology resembled each other except for higher solid content. The low glass transition temperature (T g) (106.83°C) was evident by treating low-molecular-weight samples, whereas high-molecular-weight samples exhibited high T g (125.81°C). The semicrystalline samples due to the high concentration and milky dispersion exhibited high decomposition temperature. The feed temperature, molecular weight and concentration of the samples tend to have a significant effect on the properties of spray-dried inulin.

Cellulose nanocrystals (CNC) have strong reinforcing properties when incorporated in a compatible polymer matrix. The study was conducted to investigate the effect of addition of different proportions of CNC on the mechanical, thermal and swelling properties of poly(vinyl alcohol) (PVA) nanocomposite membranes for biogas separation. The incorporation of CNC in PVA increased the crystallinity at all investigated relative humidities. No apparent trend is observed for mechanical properties for dry membranes (0% RH) with addition of CNC in PVA matrix. However, at 93% RH the elastic modulus increased 25 times with addition of CNC compared to pure PVA membranes. Moreover, tensile strength also showed twice the values at 53% RH and 93% RH after the addition of CNC. Membranes containing higher CNC content absorbed 9% less moisture. Swelling, thermal and mechanical properties indicate a good potential of CNC/PVA nanocomposite membranes for use in CO2 separation membranes. © 2017 The Korean Society of Industrial and Engineering Chemistry. Published by Elsevier B.V. This is the authors’ accepted and refereed manuscript to the article. Locked until 13 August 2019 due to copyright restrictions. This manuscript version is made available under the CC-BY-NC-ND 4.0 license http://creativecommons.org/licenses/by-nc-nd/4.0/

Bio-nanocomposites-based packaging materials have gained significance due to their prospective application in rising areas of packaged food. This research aims to fabricate biodegradable packaging films based upon polyvinyl alcohol (PVA) and starch integrated with metal-organic frameworks (MOFs) or organic additives. MOFs offer unique features in terms of surface area, mechanical strength, and chemical stability, which make them favourable for supporting materials used in fabricating polymer-based packaging materials. zeolitic imidazolate frameworks (ZIFs) are one of the potential candidates for this application due to their highly conductive network with a large surface area and high porosity. Present research illustrates a model system based on ZIF-67 (C8H10N4Co) bearing 2–10 wt.% loading in a matrix of PVA/starch blend with or without pyrolysis to probe the function of intermolecular interaction in molecular packing, tensile properties, and glass transition process. ZIF-67 nanoparticles were doped in a PVA/starch mixture, and films were fabricated using the solution casting method. It was discovered through scanning electron microscopy (SEM), X-ray diffraction (XRD), thermogravimetric analysis (TGA), and Fourier transform infrared spectroscopy (FTIR) that addition of ZIF-67 and pyrolyzed ZIF-67 changed and enhanced the thermal stability of the membrane. Moreover, 2–10 wt.% loading of ZIF-67 effected the thermal stability, owing to an interlayer aggregation of ZIF-67. The membranes containing pyrolyzed ZIF-67 showed mechanical strength in the order of 25 MPa in a moderate loading of pyrolyzed ZIF-67 (i.e., at 4 wt.%). The crystallinity enhanced by an increment in ZIF-67 loading. On the other hand, pyrolyzed ZIF-67 carbon became amorphous because of the inert environment and elevated temperature. The surface area also increased after the pyrolysis, which helped to increase the strength of the composite films.

Hemodialysis considered as therapy of end-stage renal disease (ESRD) for the separation of protein and uremic toxins based on their molecular weights using semi-permeable membranes. Cellulose Acetate (CA) hemodialysis membrane has been widely used in the biomedical field particularly for hemodialysis applications. The main issue of CA membrane is less selectivity and hemocompatibility. In this study, to enhance the filtration capability and biocompatibility of CA hemodialysis membrane modified by using Polyvinyl Alcohol (PVA) and Polyethylene Glycol (PEG) as additives. CA-PVA flat sheet membranes were cast by phase inversion method, and separation was done by dead-end filtration cell. The synthesized membranes were described in terms of chemical structure using Fourier Transform Infrared Spectroscopy (FTIR) and morphology by Scanning Electron Microscopy (SEM), Atomic Force Microscopy (AFM), pure water flux, solute permeation, and protein retention. Biocompatibility of the membranes was tested by the platelet adherence, hemolysis ratio, thrombus formation, and plasma recalcification time. SEM images exposed that the CA-PVA membrane has a uniform porous structure. 42.484 L/m2 h is the maximum pure water flux obtained. The CA-PVA rejected up to 95% of bovine serum albumin (BSA). A similar membrane separated 93% of urea and 89% of creatinine. Platelet adhesion and hemolysis ratio of casted membranes were less than the pure CA membrane. Increased clotting time and less thrombus formation on the membrane's surface showed that the fabricated membrane is biocompatible. CA-PVA hemodialysis membranes are more efficient than conventional reported hemodialysis membranes. It revealed that CA-PVA is high performing biocompatible hemodialysis membrane.

This study aims to examine the impact of Corporate Governance (CG) and Intellectual Capital (IC) on financial performance in banks listed in Pakistan stock exchange. Due to the different scope of business, the banks are dived into two groups - Commercial banks and Microfinance & investment banks, and analyzed their data separately. We have used Generalized Least Squared (GLS) model to examine the impact of Corporate Governance and Intellectual Capital, and then impact of Intellectual capital on financial performance. The results show that Corporate Governance has significant impact on intellectual capital in both groups of banks. Board ownership has positive significant coefficient only in case of microfinance & investment banks, while Board size and Board independence significantly improve intellectual capital efficiency in case of both types of banks. Human capital efficiency significantly effects financial performance in Microfinance and investment banks, whereas commercial banks improve their financial performance through structural capital efficiency.

Thermoplastic starch powders and films were produced by using different combinations of hydrophilic (malic acid and water) and amphiphilic (isoleucine and butyric acid) plasticizers. Spray drying w...

Biodegradable packaging is gaining much attention in food industry as the awareness on sustainability has increased. Thermoplastic starch is a possible alternative. This study evaluated the influence of malic acid (MA) and citric acid (CA), used as a plasticizer, on the mechanical properties of thermoplastic starch (TPS) obtained by spray drying. TPS powder was produced from solution spray drying. This powder was further compression molded to prepare TPS dog-bone test samples. X-ray Diffraction (XRD) results showed that both the spray dried TPS powder and dog-bone test samples were amorphous in nature irrespective of the amount of plasticizer added. Scanning electron microscope (SEM) was used to examine the morphology of solution spray dried TPS powder. No noticeable difference was observed in the morphology. Particles were spherical in shape with homogenous surface. The FT-IR analysis indicated the interaction of plasticizers with starch chains by hydrogen bonding. During TGA analysis, apart from moisture loss at 100 °C, samples were thermally stable up to 170 °C. Mechanical testing of TPS dog-bone revealed that sample containing malic acid as plasticizer exhibited a more elastic behavior as compared to citric acid plasticized formulations. It was revealed that the tensile strength of TPS dog-bone samples was inversely proportional to the quantity of plasticizer used.

Active and intelligent food packaging films has taken more importance over conventional packaging. The aim of this study was to develop active and intelligent food packaging films based on bio‐degradable polymers like polyvinyl alcohol and starch, incorporated with natural additives, that is, propolis extract (PE) and Anthocyanin. Boric acid was used as a cross‐linker. The results proved the compatibility of films mixture. The mechanical strength was also measured and highest value was achieved 6.1 MPa for films containing 20% PE. Moreover, the maximum zone of inhabitation, that is, 21 and 15 mm, was also achieved at same composition against Escherichia coli and methicillin‐resistant Staphylococcus aureus, respectively. Furthermore, all films had shown great color response against different pH ranging from 2 to 14. Finally, food spoilage test was performed using pasteurized milk. Films responded visibly by changing color and protected milk from spoilage. Hence, formulated bio‐degradable active and intelligent films can be used as food packaging material.

In this work, high pressure selective CO2/CH4 adsorption over functionalized covalent triazine based frameworks (CTF-NH) have been reported at high-pressure (1–20 bar) and different temperatures. The findings revealed that the successive incorporation of amine functionalities to the CTF leads to the enhancement of CO2 and CH4 adsorption capacities by 94.99% and 3.69%, respectively. The CO2 and CH4 adsorption capacities decreased with rising temperatures. The selectivity of CO2/CH4 was improved from 2.745 to 5.145. The different adsorption isotherms showed good fitting agreement with the experimentally acquired data with a lower value (AARE and R2) approaching to 1. The isotherm analysis exhibited that the adsorption is heterogeneous and satisfactory under these conditions. Dubinin-Radushkevich (D-R) isotherm analysis showed that the physisorption is dominant, with adsorption energy of less than 20 kJ/mol. Finally, thermodynamic properties revealed that at lower temperatures, the adsorption phenomenon is satisfactory, physical in nature, and exhibiting less disorder and randomness.

This study aims to assess the torrefaction of biomass as alternative renewable energy fuel to coal during co-firing. It was evaluated that torrefaction improves biomass grindability to such an extent that it can be used in coal mills with coal in co-firing without capital intensive modification. Torrefaction of beech wood was performed on a batch scale reactor at three different temperatures (200, 250 and 300 °C) with 30 min of residence time. The chemical structural changes in torrefied biomass were investigated with binding energies and FTIR (Fourier transform infrared) analysis. Monocombustion and co-combustion tests were performed to examine the combustion behaviour regarding flue gas emissions (CO, NOx and SO2) at 0.5, 1.5 and 2.5 m distance from the burner opening along with fly ash analysis. The FTIR and binding energies showed that lignin hardly affected during light torrefaction while hemicellulosic material was significantly depleted. The Hardgrove grindability index (HGI) was calculated with three methods (DIN51742, IFK and ISO). The medium temperature torrefied biomass (MTTB) yields HGI value in the range of 32–37 that was comparable with HGI of El Cerrejon coal (36–41). A slight change in temperature enabled the torrefied beech wood to be co-milled with coal without capital intensive modification and improved grindability. Comparing the combustion behaviour of single fuels, low temperature torrefied biomass (LTTB) produces less amount of NOx (426 mg/m3), CO (0.002 mg/m3) and SO2 (2 mg/m3) as compared MTTB and raw beech wood. In the case of co-combustion, it was found that blending of coal with raw biomass does not show a stable behaviour. However, premixing of 50% of coal with 50% of torrefied biomasses (MTTB and LTTB) gives most stable behaviour and reduces NOx almost 30% and SOx up to almost 50% compared to coal. The fly ash contents analysis proved that K2O contents much decreased during co-firing of coal and torrefied fuels that could cause ash related issues during combustion of raw biomass.

The present study was focused on the fabrication and characterization of polymeric wound dressings, composed of PVA and Starch. Graphitic carbon nitride (g-C3N4) was incorporated as a filler and Silver deposited-Titania nanoparticles (Ag@TiO2 NPs) as an antibacterial agent. The hydrogel membranes were fabricated by solution casting under ambient conditions. The prepared hydrogels were subjected to various characterizations techniques and obtained data demonstrated good compatibility among the constituents of the membranes. The antibacterial activity was investigated against Escherichia coli and Staphylococcus aureus. The maximum zone of inhibition achieved was 37.33 and 33.25 mm, respectively at the composition PVA/Starch/0.14GCN/0.7Ag@TiO2 NPs. Furthermore, swelling, moisture retention and water vapor transmission results demonstrated that hydrogels were capable of absorbing large volume of wound exudates. Porosity and oxygen permeability results have demonstrated that hydrogels membranes were breathable. Lastly, kinetics of drug release was performed by using various mathematical models where Higuchian model was found to be the best fit. Non-Fickian diffusion mechanism prevailed and a sustained and slow release of nanoparticles was observed. The complete healing was accomplished in seven days. The fabricated hydrogel membranes depicted better healing than conventional cotton gauze wound dressings. The prepared hydrogel membranes have demonstrated all the potential to be used as wound dressing for partial and full thickness excision wounds after complete biological characterization.