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The aquaculture industry will be crucial in helping the world's food supply and keep up with the demand. Aquaculture, like agriculture, must expand and develop sustainably in all the countries to keep up with the rising demand for food. To this end, the aquaculture industry has forged new scientific and technological frontiers in pursuit of long‐term food security. Among these is organic aquaculture, whose distinctive protocol has great potential to advance aquaculture. Organic aquaculture is being explored for multiple reasons, encompassing the aim to minimize environmental footprints, fulfill escalating consumer appetites for seafood, and contend within the industry this paper endeavors to address the gaps in current literature by offering an exhaustive overview of various aspects of organic aquaculture. This encompasses its regulation, production methods, food quality, environmental impact, economic viability, as well as socioeconomic and marketing aspects. It is necessary to acquire more knowledge about organic farming techniques before switching over to organic aquaculture on a large scale. Organic regulation, production, food quality, economic performance, and social and marketing issues are at the top. This review found that consumers lack understanding of organic principles, and regulations are inconsistently applied. However, organic aquaculture promotes social equality by protecting producers' rights to work without discrimination based on gender, race, or sexual orientation factors that ultimately boost the industry's popularity. Organic aquaculture viability varies depending on factors like feed costs, fixed expenses, and the premium pricing sensitivity, making it unfeasible for certain species. However, from both societal and economic standpoints, organic aquaculture appears most suitable for implementation in developing nations. [ABSTRACT FROM AUTHOR]

It is crucial to develop an environmentally friendly and low‐cost method to treat industrial effluent that contains soluble dyes and microbes. Most of the photocatalysts have been studied using an external light source that increases the cost of the purification process of effluent. This study focuses on developing efficient solar photocatalytic nanofoams. The controlled growth of ZnO nanofoams (CNZ nanofoams) in a simple method of thermal oxidation using a soft template is reported. Prepared nanofoams are characterized using X‐ray diffraction, scanning electon microscopy and synchrotron soft X‐ray absorption spectroscopy. By photocatalysis studies under direct sunlight it was found that within 120 min CNZ nanofoams degraded 99% of the dye. In addition, antimicrobial studies of multi‐drug‐resistant E. Fergusonii isolated from wastewater was carried out. These antimicrobial results showed a good inhibition zone, indicating that prepared nanofoams are both an effective solar photocatalyst and an antimicrobial agent. [ABSTRACT FROM AUTHOR]

In this study, the performance of a spiral aerator, a modified design of the paddlewheel aerator, was evaluated to determine its applicability in aquaculture ponds. The aeration characteristics of the spiral aerator were determined by conducting aeration experiments in a cement concrete tank of dimension 5 × 5 × 1.5 m. Nondimensional numbers related to oxygen transfer ( E) and power consumption (Ne) were proposed and expressed as functions of geometric (number of handles per shaft, n) and dynamic (Froude and Reynolds number) parameters. Simulation equations for oxygen transfer and power consumption based on the Froude criterion were developed. The maximum brake power standard aeration efficiency was achieved at n = 13. Finally, an economic analysis was performed assuming a typical Indian major carp culture pond to determine the optimum rotational speed of the aerator at different pond volumes and dissolved oxygen concentration present in the pond at which the aeration cost is minimized. The results showed that the least aeration cost is achievable when rotational speed of the spiral aerator is only 70 rpm for pond volumes up to 700 m3 and from 120 to 220 rpm for pond volumes exceeding 700 m3. [ABSTRACT FROM AUTHOR]

A series of biodegradable, semi-interpenetrating polymer network (semi-IPN) hydrogels were synthesized from a combination of carbohydrate polymer and sodium alginate (NaAlg) with acrylamide and dimethyl aminoethyl methacrylate, and crosslinked with N, N-methylenebisacrylamide via radical redox polymerization. The cytocompatibility of the hydrogels with respect to their monomers and semi-IPN hydrogels was evaluated in vitro using cultures of mouse fibroblast cell lines. This study allowed the entrapment of silver nanoparticles (NPs) into semi-IPN hydrogel networks by the in situ reduction of Ag+ ions using NaBH4 as a reducing agent. UV-visible spectroscopy confirmed the formation of silver NPs in the semi-IPN hydrogel matrix. The formation of silver NPs was also confirmed from a themogravimetric analysis weight loss difference between hydrogel and silver nanocomposite as 32%. The morphology and structure of the AgNPs present in the hydrogel networks were examined by scanning electron microscopy. Transmission electron microscopy revealed silver NPs with a size of ∼5 nm. The silver nanocomposite hydrogel exhibited good antibacterial activity against both gram positive ( Staphylococcus aureus) and gram negative ( Escherichia coli) bacteria. These results suggest that the hydrogel can be applied as wound dressings and for water purification purposes. © 2013 Wiley Periodicals, Inc. J Biomed Mater Res Part A: 102A: 3196-3206, 2014. [ABSTRACT FROM AUTHOR]

We have employed homotopy analysis method (HAM) to evaluate the approximate analytical solution of the nonlinear equation arising in the convective straight fins with temperature-dependent thermal conductivity problem. Solutions are presented for the dimensionless temperature distribution and fin efficiency of the nonlinear equation. The analytical results are compared with previous work and satisfactory agreement is noted. [ABSTRACT FROM AUTHOR]

Sodium carboxymethyl cellulose/poly(acrylamide-co-2-acrylamido-2-methylpropane sulfonic acid) semi-interpenetrating polymer network (semi-IPN) hydrogels were prepared by using free radical polymerization technique. Silver nanoparticles were formed by reduction of silver nitrate in semi-IPN hydrogels with sodium borohydrate at room temperature. UV-visible spectroscopy, thermogravimetrical analysis, X-ray diffractometry, scanning electron microscopy, and transmission electron microscopy techniques were used to characterize the formation of silver nanoparticles in hydrogels. SEM images indicated clearly the formation of group of silver nanoparticles with size range of 10-20 nm. The sizes of silver nanoparticles were also supported by transmission electron microscopy results. The semi-IPN silver nanocomposite hydrogels reported here might be a potentially smart material in the range of applications of antibacterial activity. [ABSTRACT FROM AUTHOR]

Novel polymeric mixed-matrix membranes (MMMs) were prepared by the incorporation of different amounts of 13X zeolite into a sodium carboxymethylcellulose (NaCMC)/poly(vinyl alcohol) (PVA) blend matrix. The resulting MMMs were characterized by attenuated total reflectance-Fourier transform infrared spectroscopy to analyze the possible chemical reactions between NaCMC, PVA, zeolites, and glutaraldehyde. Scanning electron microscopy, differential scanning calorimetry, thermogravimetric analysis, and X-ray diffraction were used to analyze the surface morphology, thermal stability, and crystallinity, respectively, of the membranes. Swellings studies were performed at 35°C, and we found that membranes containing 20 wt % zeolite showed higher values (960 kg m−2 h−1) at 17.5 wt % water in an isopropyl alcohol (IPA)/water mixture. Pervaporation (PV) experiments were also performed to evaluate the membrane performance in different compositions of the IPA/water mixture at 35°C. The mechanical properties were also tested, and we found that the optimum mechanical strength and percentage elongation at break were 42.24 N/mm2 and 3.38, respectively, for the membrane containing 15 wt % zeolite. The experimental results show that both the flux and selectivity increased with increasing zeolite content. The membrane containing 20 wt % zeolite showed the highest separation selectivity (5118) with a substantial flux of 0.121 kg m−2 h−1 at 35°C and with 10 wt % water in the feed; this suggested that the membranes could be used effectively to break the azeotropic point of the water-IPA mixture, so as to remove a small amount of water from IPA. © 2012 Wiley Periodicals, Inc. J Appl Polym Sci, 2012 [ABSTRACT FROM AUTHOR]

The miscibility of hydroxypropyl cellulose (HPC) and poly(vinyl pyrrolidone) (PVP) blends in aqueous solutions was studied using viscosity, ultrasonic velocity, and refractive index techniques at 30°C. The interaction parameters Δ B, μ, and α calculated from viscosity using Sun and Chee methods indicated the miscibility of this blend. This was further confirmed by ultrasonic and refractive index results. The HPC/PVP blend films are prepared by solution casting method and are analyzed by differential scanning calorimetry, X-ray diffraction, Fourier transform infrared spectroscopy, and scanning electron microscopic techniques that confirmed the complete miscibility. This miscibility is due to the strong intermolecular H-bonding interactions between OH groups of HPC and CO groups of PVP. © 2012 Wiley Periodicals, Inc. J Appl Polym Sci, 2012 [ABSTRACT FROM AUTHOR]

Sodium alginate (NaAlg)/poly (vinyl alcohol) (PVA) blend microspheres (MS) were prepared by water-in-oil (w/o) emulsion method. These polymer microspheres were crosslinked with glutaraldehyde and loaded with metformin hydrochloride (MHC). The microspheres were characterized by Fourier transform infrared spectroscopy (FTIR), differential scanning calorimetry (DSC), scanning electron microscopy (SEM), and X-ray diffraction (XRD) analysis to confirm the molecular dispersion of the drug, thermal stability, morphological properties, and crystallinity of the polymer matrix before and after blending. SEM of the microspheres suggested the formation of microspheres in spherical structure. Drug release data were analyzed using an empirical equation to understand the nature of drug transport through polymeric matrices. The controlled release (CR) characteristics of the polymer matrices was investigated in pH 7.4 media and from the results it was obtained that the drug was released in controlled manner up to 10 h. The physico-chemical properties of the microspheres were studied by calculating drug entrapment efficiency and drug release kinetics. Percent of encapsulation efficiency (% EE) decreased with increase in crosslinking agent (GA) and PVA content in the microspheres. The optimum % EE (80%) was observed in case of MS containing 40% of PVA with 15% MHC. The release profiles indicate that the release of MHC decreases with increasing the PVA/NaAlg (w/w) and drug/polymer ratio. At the end of 10 h, the highest release of MHC was found to be 96% for MS containing PVA/NaAlg (40 : 60) and 15 wt % drug loaded. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2012 [ABSTRACT FROM AUTHOR]

The miscibility of Hydroxypropyl cellulose (HPC)/poly(ethylene glycol) (PEG) blends over an extended range of concentrations in water. The viscosity, ultrasonic velocity, and refractive index of the above blend solutions have been measured at 30°C. The interaction parameters such as Δβand μ proposed by Chee and α proposed by Sun have been obtained using the viscosity data to probe the miscibility of the polymer blends. The values indicated that the blends were miscible when HPC content is more than 40% in the blend. The obtained results have been confirmed by the ultrasonic velocity and refractive index studies. The films of the blends were prepared by solution casting method using water as a solvent. The prepared films have been characterized by analytical techniques such as FTIR, DSC, X-RD, and SEM to probe the miscibility of HPC/PEG blends. The compatibility in the above compositions may be due to the formation of H-bonding between hydroxyl groups of HPC and etheric oxygen atom of PEG molecules. [ABSTRACT FROM AUTHOR]

Incorporation of zeolites into natural polymers has been shown experimentally to enhance both the flux and selectivity in pervaporative dehydration separation of organic compounds. Pervaporation is a promising membrane technique for separation of volatile organic compounds (VOCs)/water mixtures. In this study, hydrophilic sodium alginate (SA) mixed membranes were prepared using solution casting technique by incorporating zeolites into the polymer matrix. The prepared membranes were characterized by ATR-Fourier transform infrared spectroscopy (FTIR), X-ray diffraction (XRD), scanning electron microscopy (SEM), Thermal Gravimetric Analysis (TGA), and differential scanning calorimetry (DSC) were tested in a laboratory scale pervaporation experimental set-up. The effect of experimental parameters such as the type and composition of zeolites on permeation flux and selectivity was investigated. When tested on IPA-water mixtures, the zeolite-filled membrane was found to give much higher selectivity. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2011 [ABSTRACT FROM AUTHOR]

Sodium carboxymethylcellulose/poly (vinyl alcohol) mixed matrix membranes filled with different amounts 4A zeolite (0, 5, 10, 15, and 20 wt %) were prepared by solution casting method. Prepared membranes were crosslinked with GA and used for pervaporation dehydration of isopropyl alcohol of different feed mixtures at 35°C. On increment in zeolite content in the membrane it was found the improvement in the performance of the membrane, due to its hydrophilic nature and molecular sieving effect in addition to its favorable interaction with hydrophilic sodium carboxymethylcellulose and polyvinyl alcohol. The structure and chemical constituents of the MMM's were investigated by attenuated total reflectance Fourier transform infrared spectroscopy. Thermal stability of the membranes was assessed by DSC and TGA techniques. Crystallinity of the membranes was assessed using X-ray diffraction, and the morphological properties were assessed by scanning electron microscopy. Mechanical properties were also carried out to determine the tensile strength and % of elongation at break using universal testing machine. It was found that the mechanical strength increases with increase in the zeolite content upto 15 wt % of zeolite with an optimum tensile strength of 113.31 N/mm. Pervaporation was carried out to asses the membrane performance, the highest flux and selectivity obtained is 0.584 kg/m/h and 6945 for NaCMCA20 and NaCMCA15, respectively, for a feed composition containing 17.5 and 10 wt % of water in the feed and further swelling studies also supporting the pervaporation results. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2011 [ABSTRACT FROM AUTHOR]

Miscibility studies of sodium carboxymethylcellulose/poly(vinyl alcohol) (NaCMC/PVA) blends of different compositions (100/0, 80 : 20, 60 : 40, 50 : 50, 40 : 60, 20 : 80, and 0 : 100) were investigated using viscometric method. NaCMC, PVA, and their blend membranes were prepared by solution-casting technique and were then crosslinked with glutaraldehyde (GA). The effect of blend composition on mechanical, swelling, and pervaporation results (flux and selectivity) was also investigated in this study. Attenuated total reflectance-Fourier transform infrared spectroscopy (ATR-FTIR) results showed that the blends are miscible over the entire studied composition range and further confirmed the crosslinking reaction with GA. FTIR studies reveal that the blends containing 50 : 50 (NaCMC/PVA) are an optimum miscible blend. Thermogravimetric analysis confirms that the thermal stability increased with increase in NaCMC content in NaCMC/PVA blend membrane. XRD and DSC showed a corresponding decrease in crystallinity and increase in melting point with increase in NACMC content, respectively. NaCMC/PVA blends of all the composition under study were used for dehydration of isopropyl alcohol at different compositions of IPA/water mixture (90 : 10, 87.5 : 12.5, 85 : 15, and 82.5 : 17.5) at 35°C. Swelling studies and PV results reveal that increase in NaCMC content in the blend leads to an increase in flux of water, whereas selectivity decreases. The optimum flux and selectivity were observed for the blend containing 50 : 50 NaCMC/PVA content at a feed ratio of 87.5 : 12.5 IPA/water. © 2010 Wiley Periodicals, Inc. J Appl Polym Sci, 2011 [ABSTRACT FROM AUTHOR]

The title compounds (7a-h) were prepared by esterification of indole-5-carboxylic acid (1) and subsequent treatment with hydrazine hydrate in methanol via the hydrazide (3). Finally hydrazide (3) condensed with different substituted aldol (6) in acetic acid / PTSA catalytic media produced (3,5-subsituted-4,5-dihydropyrazol-1-yl)(1H-indol-5-yl)methanone (7a-h) in good yields. All the newly synthesized compounds are by elemental analysis and spectral studies and evaluated for antimicrobial activities. [ABSTRACT FROM AUTHOR]

A naturally occurring fabric belonging to the species Hardwikia binata was extracted from the sheath of stem, bark, and branches of the tree. The fabric specimens were treated with sodium hydroxide and poly (vinyl alcohol). The morphology of the fabric specimens before and after NaOH treatment was studied using scanning electron microscopy technique. Ligno-cellulosic properties of fabric were analyzed by XRD, FTIR, and thermo gravimetric methods before and after NaOH treatment. Tensile strength and percentage of elongation at break of the fabric were also studied by using a universal testing machine (model AGS-10kNG). The results showed that the poly (vinyl alcohol)-treated fabric specimens showed higher tensile strength than sodium hydroxide-treated fabric specimens. The Binata fabric has good thermal resistance and was also found to increase by alkali treatment. The FTIR method indicates lowering the hemi cellulose and lignin content by alkali treatment in the fabric. Further, the X-ray diffraction studies revealed an increase in crystallinity of the fabric by alkali treatment. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2010 [ABSTRACT FROM AUTHOR]

The article presents a study which described the synthesis of water-glass-based silica aerogel powder through coprecursor method with and without squeezing of hydrogels in drying technique. Brunaeur, Emmett, and Teller, Barett-Joyner-Halenda, and field emission scanning electron microscope techniques were employed to characterize aerogel powder. The properties of the aerogel powder obtained by squeezing were found to be superior to those dried in a furnace one.

The article discusses a study which determined the thermosensitive property of semi-interpenetrating network (IPN) microspheres through water-in-oil emulsification process. Sodium alginate (NaAlg) and N-isopropylacrylamide (NIPAAm) microspheres were characterized by Fourier transform infrared spectroscopy (FTIR) and surface morphology by differential scanning calorimetry (DSC). The dispersion of 5-fluorouracil (5-FU) at the molecular level at 25 and 37 degrees Centigrade is revealed.