Investigations on Different Decay Modes of Darmstadtium

Physics of Particles and Nuclei Letters - We have studied the competition between different decay modes such as binary, ternary, cluster radioactivity and alpha decay. The competition between...     

Modeling of fixed-bed column studies for removal of cobalt ions from aqueous solution using <Emphasis Type="Italic">Chrysanthemum indicum</Emphasis>

The present study investigates the adsorption capability of raw and biochar forms of Chrysanthemum indicum flowers biomass to remove cobalt ions from aqueous solution in a fixed-bed column. Column adsorption experiments were conducted by varying the bed height (1.0, 2.0, 3.0 cm), flow rate (1.0, 2.5, 5.0 mL min^?1) and initial cobalt ion concentration (25, 50, 75 mg L^?1) to obtain the experimental breakthrough curves. The adsorption capacity of the raw and biochar forms of C. indicum flowers were found to be 14.84 and 28.34 mg g^?1, respectively, for an initial ion concentration of 50 mg L^?1 at 1.0 cm bed height and 1.0 mL min^?1 flow rate for Co (II) ion adsorption. Adam–Bohart, Thomas and Yoon–Nelson models were applied to the experimental column data to analyze the column performance. The Thomas model was found to best represent the column data with the predicted and experimental uptake capacity values correlating well and with higher R ² values for all the varying process parameters. Desorption studies revealed the suitability of the adsorbents for repeated use up to four adsorption–desorption cycles without significant loss in its efficiency. It can thus be inferred from the fixed-bed column studies that C. indicum flowers can suitably be used as an effective adsorbent for Co (II) ion removal from aqueous solution on a higher scale.     

Investigation of Ti6Al4V and AA7075 alloy embedded nanofluid flow over longitudinal porous fin in the presence of internal heat generation and convective condition

The thermal attributes of porous fin due to radiation and natural convection have been carried out in the presence of nanofluid flow. The geometry of the fin taken for the analysis is rectangular profiled longitudinal fin. The temperature-dependent internal heat generation condition is also considered along with Darcy's model. The two types of nanofluid containing titanium alloy(Ti6Al4V) and aluminium alloy(AA7075) immersed in water is considered for the investigation.The modelled nonlinear ordinary differential equation is numerically solved by the Runge–Kutta–Fehlberg technique. The impact of geometric parameter on the heat transfer analysis of the fin due to the flow of both nanofluids is plotted and consequences are physically interpreted. It is observed that the presence of the water-based titanium alloy better enhances the fin heat transfer rate.     

Effects of stretching/shrinking on the thermal performance of a fully wetted convective-radiative longitudinal fin of exponential profile

The present investigation focuses on the thermal performance of a fully wet stretching/shrinking longitudinal fin of exponential profile coated with a mechanism like a conveyer belt. The modeled equation is non-dimensionalized and solved by applying the Runge-Kutta-Fehlberg(RKF) method. The effects of parameters such as the wet parameter, the fin shape parameter, and the stretching/shrinking parameter on the heat transfer and thermal characteristics of the fin are graphically analyzed and discus...     

Efficient Room-Temperature Synthesis and Antimicrobial Study of Novel 2-Aroylbenzofuran-3-ols from Substituted Methyl Salicylates and Phenacyl Bromides

The article describes a convenient and efficient synthetic route for the construction of 2-aroylbenzofuran-3-ols from readily available diverse methyl salicylates and phenacyl bromides using K₂CO₃ as catalyst in dimethylformamide as solvent at room temperature. The reaction involves two steps, which occur in quick succession within 1 h to deliver the product with reasonably high yields. All the synthesized 2-aroylbenzofuran-3-ols (4a–u) were subjected for their antimicrobial studies, and some of these have shown prominent activity.

[Supplementary materials are available for this article. Go to the publisher's online edition of Synthetic Communications® for the following free supplemental resource(s): Full experimental and spectral details.]     

Green Approach for the Synthesis of a New Class of Diamidomethane‐linked Benzazolyl Pyrazoles and Evaluation as Antifungals

A new class of diamidomethane‐linked benzoxazolyl pyrazoles, benzothiazolyl pyrazoles, and benzimidazolyl pyrazoles were synthesized from the synthetic intermediates N‐benzazolylcarbamoylmethylcinnamides adopting environmentally benign methods. In fact, nitrile imine was generated from araldehyde phenylhydrazone in the presence of iodosobenzene and cetyltrimethylammonium bromide followed by oxidation with iodine in dimethylsulfoxide. The structures of compounds were characterized by IR, ¹H NMR, ¹³C NMR, and mass spectra. The title compounds were also evaluated for their antifungal activity. Amongst all the tested compounds benzimidazolyl pyrazolyl carboxamides ( 13a and 13b ) were found to be potential antifungal agents.     

Enantioselective Synthesis of C−O Axially Chiral Diaryl Ethers by NHC-Catalyzed Atroposelective Desymmetrization**

Axially chiral diaryl ethers, a distinguished class of atropisomers possessing unique dual C−O axis, hold immense potential for diverse research domains. In contrast to the catalytic enantioselective synthesis of conventional single axis bearing atropisomers, the atroposelective synthesis of axially chiral ethers containing flexible C−O axis remains a significant challenge. Herein, we demonstrate the first N-heterocyclic carbene (NHC)-catalyzed synthesis of axially chiral diaryl ethers via atroposelective esterification of dialdehyde-containing diaryl ethers. Mechanistically, the reaction proceeds via NHC-catalyzed desymmetrization strategy to afford the corresponding axially chiral diaryl ether atropisomers in good yields and high enantioselectivities under mild conditions. The derivatization of the synthesized product expands the utility of present strategy via access to a library of C−O axially chiral compounds. The temperature dependency and preliminary investigations on the racemization barrier of C−O bonds are also presented.     

Significance of buoyancy and Lorentz forces on water-conveying iron(III) oxide and silver nanoparticles in a rectangular cavity mounted with two heated fins: heat transfer analysis

Journal of Thermal Analysis and Calorimetry - During the production of iron(iii) oxide and silver nanoparticles where water is inevitable, little is known on the transport phenomenon in a...     

Quinoline and 2-nitroimino-1, 3-diazacycloalkane hybrids: Design,synthesis and insecticidal activity

A library of new hybrid molecules comprising quinoline, 2-nitroimino-1, 3-diazacycloalkane motifs were designed and synthesized as plausible neonicotinoid analogues. These compounds were synthesized from 2-chloro/aryloxy-3-formyl quinolines and guanidine nitrate with the coupling of 2-chloro/aryloxy-3-(chloromethyl)quinolines, 2-nitroimino-1, 3-diazacycloalkanes under phase transfer catalysis (PTC) as crucial step. All the compounds were obtained in excellent yields (80–90%) and were characterized by ¹H, ¹³C NMR and mass spectrometry. The newly generated compounds were screened for insecticidal activity against aphids in safflower field and some of them displayed moderate activity.