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Fixed point results of almost generalized -contractive mappings in ordered b-metric spaces
No full textThe aim of this article is to establish some fixed point, coupled coincidence point and coupled common fixed point results form app ings satisfying an almost generalized(φ,ψ,θ)s
contractive conditions in the frame work of partially ordered b-metric spaces. These results generalize, extend and unify several comparable results in the existing literature. Few examples are illustrated to support our result
Sustainable removal of Cr(VI) from wastewater by Peltophorum pterocarpum leaf powder
No full textHeavy metals discharged from various industrial activities instigate a significant risk to health risk and the environmental hazards. Numerous methods are available (namely electro-dialysis, ion exchange, membrane filtration, ultrafiltration and reverse osmosis) for removing heavy metals from industrial effluent. Chromium mainly hexavalent chromium i.e. Cr(VI) is considered to be one of the most toxic heavy metals amongst the list. The present work emphasizes on biosorption of Cr(VI) towards efficient removal. The current work highlights on optimization of process variable, which is influencing the removal through biosorption using Peltophorum pterocarpum leaf powder. The experimental design of Box-Behnken was applied to determine the
optimum parametric conditions. Characterization of Peltophorum pterocarpum leaf powder ( PPL ) was carried out through FTIR and SEM analysis. The highest removal percentage was attained 90.94 through biosorption at pH- 4.15, initial concentration of 39.81 mg L -1 and biosorbent dosage of 0.3 g. The experimental sorption study obeyed the Langmuir isotherm and pseudo second-order kinetic models. Desorption studies were performed with 0.1N NaOH solution for the regeneration of biosorbent. The entire experimental results concluded that Peltophorum pterocarpum leaf ( PPL) powder could be a potential biosorbent for removal of hexavalent chromium from industrial wastewater
A review on reverse micellar approach for natural fiber dyeing
Get PDFThis study reviews the need and importance of non‐aqueous dyeing systems in the chemical processing industry, especially using the reverse micellar system in the dyeing of natural fibers. When it comes to conventional dyeing systems, which use large quantities of water, chemical, and energy, cause a lot of effluent load to the environment. Again the effluent water has to be treated well to eliminate all the harmful substances in it. To overcome the issues, a lot of research has been carried out in this area to minimize the use of water and chemicals in the dyeing process. Like use of low material to liquor (M:L) ratio in dyeing, dyes with high fixation at lower temperatures, low/salt less dyeing in case of reactive dyeing with cotton, cottonseed oil dyeing, microwave‐assisted dyeing, and use of supercritical carbon dioxide in case of polyester dyeing and many more. All the above said methods are aqueous‐based and, after the completion of dyeing, results in wastewater generation, which requires further treatment to reduce the harmful chemicals. Therefore, to further minimize the use of water and chemicals in the dyeing of natural fibers reverse micellar system has been introduced with the help of surfactants of both Ionic and non‐ionic in nature. As of today, a lot of work has been carried out in the dyeing of natural fibers with this system by employing Ionic, non‐ionic, and mixed surfactants. Fascinating results were obtained in the dyeing with good levelness, high exhaustion, and fixation values, and results were compared with conventional dyeing. Computer color matching studies were also done better to understand the applicability of these systems in the industry and found nearer results
Anti-inflammatory and antioxidant activities of 4-allylpyrocatechol and its derivatives with molecular docking and ADMET investigations
Get PDFAbnormal production of pro-inflammatory mediators and generation of reactive oxygen species (ROS) play a key role in the development and progression of various human disorders. The study aims to investigate the in vitro anti-inflammatory and antioxidant activity of 4-allyl pyrocatechol (4-APC) and its derivatives (APC-1 and APC-2) by albumin denaturation and 1,1-Diphenyl-2-picrylhydrazyl (DPPH) methods, respectively. Also, the test compounds are studied in silico for their inhibitory potential against the pro-inflammatory and oxidative markers (calpain, FAAH, and TNF-α) via molecular docking. The compounds have exhibited appre- ciable in vitro anti-inflammatory and antioxidant activities. The APC-2 compound has demonstrated significant anti-inflammatory and antioxidant activity (percentage inhibition = 69±0.76 and 77.05±0.92, respectively, at 100 μg/ml) compared to the standard drugs, aspirin and ascorbic acid (percentage inhibition = 82±0.83 and 92.35±0.75, respectively, at 100 μg/ml). The docking study has showed that APC-2 significantly inhibited calpain (PDB ID: 2R9C), FAAH (2WJ1) and TNF-α (2AZ5) inflammatory markers. The drug-likeness, bioactivities, ADME profile (pharmacokinetic) and toxicity properties have also been determined using online tools (Molinspiration, pkCSM, SwissADME, PreADMET). The test compounds have showed accepta- ble drug-likeness, bioactivity score, ADME and toxicity properties. Finally, we conclude that the 4-allylpyrocatechol and its derivatives can be used as lead molecules for their further development as therapeutically useful anti-inflammatory agent
Design, Development, Optimization and Evaluation of Ranolazine Extended Release Tablets
Get PDFObjectives: The objective of the current study was to develop an extended release (XR) tablet formulation for ranolazine using Eudragit L 100-55 and hydroxypropylmethylcellulose (HPMC) K100M in an appropriate composition. Ranolazine, an anti-anginal agent, is mainly used for treating chronic stable angina pectoris. The main advantage of this drug that it exhibits anti-ischemic effect, which was not influenced by either blood pressure or heart rate.
Materials and Methods: XR tablets of ranolazine were prepared using variable amounts of Eudragit L 100-55 and HPMC K100M in various proportions as per 32 factorial design by direct compression technique. The amount of polymers with desired sustained drug release was labeled as factors. On other hand, time taken for drug dissolution was labeled as responses (t10%, t50%, t75%, t90%).
Results: Nine formulations were obtained as per design, developed, and evaluated for quality control parameters. The obtained results clear that all formulations pass the compendial limits. Data obtained from the dissolution study fitted well to kinetic modeling and kinetic parameters were determined. Polynomial equations were derived for responses and checked for validity.
Conclusion: RF5 composed of 31.25 mg of Eudragit L 100-55 and 31.25 mg of HPMC K100M, is the best formulation showing similarity f2: 85.78, f1:2.32 with the marketed product (RANEXA). Formulation RF5 follows zero order, whereas the release mechanism was found to be non-fickian type(n= 0.65)
Silver-sepiolite (Ag-Sep) hybrid reinforced active gelatin/date waste extract (DSWE) blend composite films for food packaging application
No full textABSTRACT
In this study, date syrup waste extract (DSWE) (15 wt%) and different content of silver doped sepiolite hybrid (Ag-Sep, 0.25–3 wt%) were incorporated into gelatin matrix to develop a series of active composite packaging films. Incorporating 2 wt% of Ag-Sep increased the modulus of blend film by 98% compared to unmodified gelatin/DSWE blend film. The active gelatin composite film exhibited superior active compounds migration to aqueous food simulants. Besides, Ag-Sep provided a tortuous pathway to the composite film, resulting in high 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical inhibition efficiency (91%) and slow-release kinetics of active compounds to the food simulant. The Ag-Sep hybrid was improved the antimicrobial property of the gelatin/ DSWE blend film against both gram-negative and gram-positive microbes. Thus, this study demonstrated that the Ag-Sep hybrid exhibits significant properties in the active gelatin composite films, implying that this hybrid could be an effective additive for various active packaging films
Intrinsic approach of eco‑friendly poly benzoxazine‑co‑maleicanhydride) materials for self‑healing applications
No full textAbstract
In modern era, self-healing polymers have been under investigation due to their exclusive mechanical, thermal and electrical properties that could potentially make them enormously valuable in abundant engineering applications. This work explores a new strategy to develop bio-based eco-friendly poly(benzoxazine-co-maleicanhydride) [poly(E-aee-co-MA)] materials for intrinsic autonomous self-healing applications. Here in, renewable Eugenol (E), aminoethoxyethanol (aee) and paraformal�dehyde was chosen to synthesize a biobased E-aee monomer with hydroxy functionality through Mannich like ring closure reaction. Later, E-aee was copolymerized with maleic anhydride (MA) precursor through thermal ring opening polymeriza�tion. The structural features of the resulting E-aee and pre(E-aee-co-MA) materials were confrmed by 1
H NMR and FT-IR spectroscopy. The optical property of the E-aee measured by using fuorescent spectrum. We used DSC and FT-IR spec�troscopy to investigate the polymerization behavior of biobased benzoxazine monomer (poly(E-aee)) and the copolymer of
poly(E-aee-co-MA). DMA and TGA were used to determine the mechanical and thermal properties of cross linked biobased
benzoxazine. SEM and optical microscope were used to screening the self-healing behavior of poly[E-aee-co-MA]. The
developed poly[E-aee-co-MA] shows good and repeated self-healing ability due to supra-molecular action and inter and intra
hydrogen bonding interactions between carboxylic acid and hydroxy functionality in the network structure and confrmed
by computational studies in density functional theory (DFT) calculation. Especially, the described self-healing biobased
benzoxazine were manufactured with readily available raw-materials, they are fast to manufacture and shape controller
Total Synthesis of (–)-Panduratin D
No full textHerein, an enantioselective total synthesis of (–)-panduratin D, a
novel secondary metabolite against human pancreatic PANC-1
cancer cell, from commercially available 3-methoxyphenol is
reported. The synthesis was completed in nine steps and the key
features include Sonogashira coupling, anionic Snieckus−Fries
rearrangement, directed ortho metalation, tandem Si → C Alkyl
rearrangement/Claisen−Schmidt condensation, and chiral boron
complex-promoted asymmetric Diels–Alder cycloaddition. These
endeavors could facilitate the biological studies of (–)-panduratin D
and its analog
Nonisolated DC to DC Converters for High-Voltage Gain Applications Using the MPPT Approach
Get PDFIt is proved and examined in this research paper that the perturb and observe (P and O) technique for isolating the photovoltaic
array (PVA) from the power structure may be used to isolate the PV array from the power structure. A single specied voltage
setup can remove the maximum power from a PV cell because of the nonlinear properties of the PV cell’s output. As a result, in
PVA, the maximum power point tracking (MPPT) algorithm is utilized to increase the yield control range by increasing the
maximum power point. In this study, the MPPT computations are carried out with the assistance of a DC-DC boost converter for usage in applications needing high voltage gain at a variety of sun-positioned irradiances and cell temperatures, as demonstrated in the literatur
Effect of Mg doping on the electrical, dielectric and relaxation properties of LiMnPO4 nanoparticles
No full textLiMnPO4 and LiMn0.9Mg0.1PO4 nanostructures were synthesized by a rapid microwave-assisted solvothermal method. Powder X-ray diffraction (XRD) studies confirmed the orthorhombic crystal structure of LiMnPO4 and LiMn0.9Mg0.1PO4 nanostructures. It is also noticed that the Mg2+ ions doping into manganese sites did not affect the crystal structure of LiMnPO4. The scanning electron microscope (SEM) micrographs of LiMnPO4 and LiMn0.9Mg0.1PO4 showed the formation of nanoparticles with mixed morphology, i.e., spherical particle morphology and one-dimensional nanorod morphology. The LiMn0.9Mg0.1PO4 nanoparticles exhibited an improved electrical properties compared to that of LiMnPO4 nanoparticles. At room temperature, LiMn0.9Mg0.1PO4 nanoparticles exhibited an electrical conductivity of 3.705 × 10–7 S cm−1. The dielectric constant of LiMnPO4 and LiMn0.9Mg0.1PO4 nanostructures is high at low frequencies and decreases gradually towards high frequencies. The LiMnPO4 and LiMn0.9Mg0.1PO4 nanostructures are found to exhibit non-Debye-type relaxation behavior