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11.
Vipul Desai Dr. Vinay S. Sharma Suryajit L. Rathod Dr. Anuj S. Sharma Hitendra A. Mali Dr. Rutesh R. Shah Prof. Pranav S. Shrivastav 《Chemphyschem》2023,24(9):e202200803
Four new azo-based supramolecular materials containing thiacalixarene core substituted by variable alkoxy groups ( TFA1 – TFA4 ) have been designed and synthesized for the mesomorphic and photoswitching properties. The liquid crystalline behavior were accomplished by using DSC, POM, and XRD studies. All azo-based thiacalixarene based materials with short and higher chain length display columnar hexagonal mesophase with broad temperature range. The thermal behavior of all the materials was investigated by DSC and TGA study. The structural and conformational study of the lower rim functionalized materials was confirmed by using different techniques. These thiacalixarene moulded liquid crystalline compounds shows columnar self-assembly type behavior and higher thermal stability. The introduction of bi-substituted azo-ester network towards the lower rim of thiacalixarene core has impact on the electron delocalization and liquid crystalline properties. The photoswitching properties suggested cis and trans azo-isomerization under radiation of UV light and higher thermal back relaxation time. The mesogenic behaviour of compound TFA2 and TFA4 were demolished by the influence of cis and trans isomerization. The structure-property correlation is studied to understand the variation in mesogenic properties with the substitution of variable alkoxy side chain. 相似文献
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Patil Chandrashekhar Suryawanshi Rahul Borase Hemant Narkhede Chandrakant Salunke Bipinchandra 《Natural product research》2015,29(24):2350-2354
Mosquito control protein from Bacillus thuringiensis gets inactivated with exposure to sunlight. To address this issue, the potential of synthetic and natural dye was investigated as sunlight protectants. Bt SV2 in absence of dyes when exposed to sunlight showed reduced effectiveness against the fourth instars of mosquito larvae. Whereas acriflavin, congo red and violacein were able to maintain 86.4%, 91.6% and 82.2% mosquito larvicidal efficacy of Bt SV2 against IVth instars larvae of Anopheles stephensi Meigen after exposure to sunlight. Similarly, beetroot dye, acriflavin, congo red and violacein maintained 98.4%, 97.1%, 90.8% and 70.7% larvicidal activities against Aedes aegypti Linnaeus after sunlight exposure. Prodigiosin was found to be the best photo-protectant by simultaneously protecting and enhancing Bt activity by 6.16% and 22.16% against A. stephensi and A. aegypti, respectively. Combination of dyes with Bt formulations can be a good strategy for mosquito control programmes in tropical and sub-tropical regions. 相似文献
14.
Elution profiles of lanthanides with α‐hydroxyisobutyric acid by ion exchange chromatography using fine resin 下载免费PDF全文
Rahul Trikha Bal Krishan Sharma Kanwal Nain Sabharwal Krishan Prabhu 《Journal of separation science》2015,38(21):3810-3814
Experiments were carried out using a strong acid cation exchange resin with a particle size of 75–150 μm, termed as “fine resin” in hydrogen ion form for the elution of individual lanthanides Sm, Eu, Gd, Tb, and Dy that are produced as fission products in the spent nuclear fuel and generated in the effluent during reprocessing of spent nuclear fuel. Batch experiments were carried out to study the effect of concentration of nitric acid on distribution coefficient. The distribution coefficient values for these individual lanthanides were determined in nitric acid medium in the concentration range of 0.01–4.0 N. Uptake of each individual lanthanide by resin was increased with increased nitric acid concentration from 0.01 to 0.5 N and remained similar from 0.5 to 1.0 N and decreased thereafter up to 4.0 N. Column experiments were also carried out using the same resin to study the parameters like pH of the eluent, flow rate, and resin bed height under isocratic elution conditions for eluting lanthanide elements using α‐hydroxyisobutyric acid as eluent. The results of this study have indicated the possibility for the elution of individual lanthanides. 相似文献
15.
Harshitha Barike Aiyappa Subhadeep Saha Pritish Wadge Rahul Banerjee Sreekumar Kurungot 《Chemical science》2015,6(1):603-607
A proton conducting metallogel [FNPA; ferric nitrate (FN)–phytic acid (PA)] is synthesized by immobilizing a protogenic ligand (phytic acid) using iron(iii) nitrate in DMF. The xerogel shows high proton conductivity of 2.4 × 10–2 S cm–1 at 120 °C, the best value known among all metal organic materials (MOMs). Marking the first such attempt in MOMs, an electrode made using the xerogel showed a power density of 0.94 mW cm–2 at 0.6 V under dry fuel cell conditions. 相似文献
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Structural Chemistry - Calix[4]arenes are the most renowned and widely studied calix[n]arenes, which are established to have quite a few biological (e.g., antibacterial, antifungal, antioxidant,... 相似文献
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Rahul A. Patil Mohsen Talebi Leonard M. Sidisky Daniel W. Armstrong 《Chromatographia》2017,80(10):1563-1574
Dicationic ionic liquids (ILs) are widely used as gas chromatography (GC) stationary phases as they show higher thermal stabilities, variety of polarities, and unique selectivities towards certain compounds. An important aspect contributing to them is that they show multiple solvation interactions compared to the traditional GC stationary phases. Dicationic ILs are considered as combination of three structural moieties: (1) cationic head groups; (2) a linkage chain; and (3) the counter anions. Modifications in these structural moieties can alter the chromatographic properties of IL stationary phases. In this study, a series of nine thermally stable IL stationary phases were synthesized by the combination of five different cations, two different linkage chains, and two different anions. Different test mixtures composed of a variety of compounds having different functional groups and polarities were analyzed on these columns. A comparison of the separation patterns of these different compounds on nine different IL columns provided some insights about the effects of structural modifications on the selectivities and polarities of dicationic ILs. 相似文献
18.
Vinay K. Singh Rahul Dubey Abhishek Upadhyay Laxmi Kant Sharma Rana Krishna Pal Singh 《Tetrahedron letters》2017,58(45):4227-4231
An efficient and economical method was developed for synthesis of 3-substituted indole by using electrochemically induced condensation of various aldehyde, indole and malononitrile. 相似文献
19.
Amit M. Jabgunde Rahul S. Patil Swarup De Eveline Lescrinier Steven De Jonghe Leonid Beigelman Piet Herdewijn 《Tetrahedron》2019,75(8):1107-1114
The synthesis of 3′-fluoro-4′-amino-hexitol nucleosides with a uracil and cytosine nucleobase was performed. The synthesis started from 1,5:2,3-dianhydro-4,6-benzylidene-allitol and afforded the target compounds in 15 steps. These protected hexitol nucleosides are valuable building blocks for the preparation of a new class of oligonucleotides. 相似文献
20.
Gupta Sanjay Kumar Misra Rahul Dev 《Journal of Thermal Analysis and Calorimetry》2019,136(4):1781-1793
Journal of Thermal Analysis and Calorimetry - In order to decrease the energy consumptions in energy conversion devices, boiling heat transfer augmentation is one of the important research... 相似文献