Experimental investigation of TiO2–water nanofluid flow and heat transfer inside wavy mini-channel heat sinks

Journal of Thermal Analysis and Calorimetry - The present study comprises experimental investigation on heat transfer and hydrodynamic characteristics of TiO2 nanofluid as coolant in wavy channel...     

Thermal performance enhancement of shell and helical coil heat exchanger using MWCNTs/water nanofluid

Journal of Thermal Analysis and Calorimetry - Heat exchangers serve as pivotal components in industries. Enhancement in the performance of heat exchangers has been the focus of researchers in the...     

Synthesis of isoniazid-1,2,3-triazole conjugates: Antitubercular,antimicrobial evaluation and molecular docking study

In the present study, a series of new isoniazid-1,2,3-triazole conjugates ( 5a-k ) was synthesized via click chemistry approach. The newly synthesized compounds were assessed for their in vitro antitubercular and antimicrobial activities. The compound 5g has displayed potent antitubercular activity against Mycobacterium tuberculosis H37Rv (Mtb) with MIC value 1.56 μg/mL. The active compounds were screened for their cytotoxicity profile by MTT assay against RAW 264.7 cell line. The four compounds have shown good in vitro antimicrobial activities against both antibacterial and antifungal pathogens. A molecular docking study was accomplished to identify the probable mode of action of synthesized derivatives. These compounds have shown excellent binding affinity toward Enoyl-acp reductase (INHA) and DNA gyrase.     

Effects of Essential Oils of Elettaria cardamomum Grown in India and Guatemala on Gram-Negative Bacteria and Gastrointestinal Disorders

The present study examined the chemical composition and antimicrobial and gastrointestinal activity of the essential oils of Elettaria cardamomum (L.) Maton harvested in India (EC-I) and Guatemala (EC-G). Monoterpenes were present in higher concentration in EC-I (83.24%) than in EC-G (73.03%), whereas sesquiterpenes were present in a higher concentration in EC-G (18.35%) than in EC-I (9.27%). Minimum inhibitory concentrations (MICs) of 0.5 and 0.25 mg/mL were demonstrated against Pseudomonas aeruginosa in EC-G and EC-I, respectively, whereas MICs of 1 and 0.5 mg/mL were demonstrated against Escherichia coli in EC-G and EC-I, respectively. The treatment with control had the highest kill-time potential, whereas the treatment with oils had shorter kill-time. EC-I was observed to be more potent in the castor oil-induced diarrhea model than EC-G. At 100 and 200 mg/kg, P.O., EC-I exhibited 40% and 80% protection, respectively, and EC-G exhibited 20% and 60% protection, respectively, in mice, whereas loperamide (10 mg/kg, i.p., positive control) exhibited 100% protection. In the in vitro experiments, EC-I inhibited both carbachol (CCh, 1 µM) and high K⁺ (80 mM)-induced contractions at significantly lower concentrations than EC-G. Thus, EC-I significantly inhibited P. aeruginosa and E. coli and exhibited more potent antidiarrheal and antispasmodic effects than EC-G.     

Catalytic Conversion of Xylose to Furfural by p-Toluenesulfonic Acid (pTSA) and Chlorides: Process Optimization and Kinetic Modeling

Furfural is one of the most promising precursor chemicals with an extended range of downstream derivatives. In this work, conversion of xylose to produce furfural was performed by employing p-toluenesulfonic acid (pTSA) as a catalyst in DMSO medium at moderate temperature and atmospheric pressure. The production process was optimized based on kinetic modeling of xylose conversion to furfural alongwith simultaneous formation of humin from xylose and furfural. The synergetic effects of organic acids and Lewis acids were investigated. Results showed that the catalyst pTSA-CrCl₃·6H₂O was a promising combined catalyst due to the high furfural yield (53.10%) at a moderate temperature of 120 °C. Observed kinetic modeling illustrated that the condensation of furfural in the DMSO solvent medium actually could be neglected. The established model was found to be satisfactory and could be well applied for process simulation and optimization with adequate accuracy. The estimated values of activation energies for xylose dehydration, condensation of xylose, and furfural to humin were 81.80, 66.50, and 93.02 kJ/mol, respectively.     

Decrease in the Particle Size and Coercivity of Self‐Assembled CoNi Nanoparticles Synthesized Under a Repulsive Magnetic Field

Towards the challenge for synthesis of smaller‐sized heterostructures and hybrid composites for nanomagnets and magnetic fluid applications. Here, a novel method is reported to reduce the particle size of Cobalt–Nickel (CoNi) magnetic nanoparticles by placing them between a static, repulsive magnetic field (N–N/S–S) during synthesis in contrast to the conventional method of applying an attractive (N–S) magnetic field. The obtained smaller sized‐CoNi nanoparticles (≈40 nm) possess a uniform size, an excellent monodispersity, and outstanding magnetic properties. The results clearly demonstrate that the size and morphology change of CoNi nanoparticles have great influence on their magnetic properties. This study provides a footprint to design new heterostructured magnetic nanomaterials under the same‐poled magnetic field for potential applications in magnetic fluids, spintronics, and other related industries.     

Subtle Effect of Alkyl Substituted π-Bridges on Dibenzo[a,c]phenazine Based Polymer Donors towards Enhanced Photovoltaic Performance

Chinese Journal of Polymer Science - Selection of the strategically substituted alkyl chains has a significant effect to modulate the physical properties of conjugated polymers, electro-optical...     

Single step conversion of UO2 and U3U8 into uranyl sulphate solution

A direct and simple method for the conversion of UO₂ and U₃O₈ powder into uranyl sulphate solution is described, eliminating many tedious chemical steps. UO₂ and U₃O₈ are not soluble in concentrated or dilute sulphuric acid, as uranium in lower oxidation state does not react with sulphuric acid. However, nitric acid oxidizes uranium from lower valency to higher valency state, i.e., tetravalent to the hexavalent uranyl ion in solution. Sufficient amount of sulphuric acid present in the reaction mixture makes it possible for uranyl ions, formed by oxidation of nitric acid, to react with sulphuric acid forming uranyl sulphate.     

Integrating the use of linear and dynamic programming methods for dairy cow diet formulation

Despite many refinements that have been made to the basic Linear Programming model used to find economically optimal diets for dairy cows, the sequential nature of the physical and physiological changes that a cow goes through during lactation have not been incorporated into the modelling process satisfactorily. This paper demonstrates how it can be achieved by integrating the use of both Linear and Dynamic Programming methods to optimise the economic performance of a dairy cow over its entire lactation. Linear Programming generates solutions for each potential liveweight change occurring during each of eleven four week periods over the lactation, then the use of DP allows both the selection of the optimal sequence of liveweight changes during the lactation and the specification of rations associated with this optimal path.