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31.
Rahul S. Patil Dr. Debasis Banerjee Cory M. Simon Prof. Jerry L. Atwood Dr. Praveen K. Thallapally 《Chemistry (Weinheim an der Bergstrasse, Germany)》2016,22(36):12618-12623
Separation of xenon and krypton is of industrial and environmental concern; the existing technologies use cryogenic distillation. Thus, a cost‐effective, alternative technology for the separation of Xe and Kr and their capture from air is of significant importance. Herein, we report the selective Xe uptake in a crystalline porous organic oligomeric molecule, noria, and its structural analogue, PgC‐noria, under ambient conditions. The selectivity of noria towards Xe arises from its tailored pore size and small cavities, which allows a directed non‐bonding interaction of Xe atoms with a large number of carbon atoms of the noria molecular wheel in a confined space. 相似文献
32.
Tetraphenylethene‐Based Conjugated Fluoranthene: A Potential Fluorescent Probe for Detection of Nitroaromatic Compounds 下载免费PDF全文
Dr. Yogesh Chandrasekaran Dr. Nutalapati Venkatramaiah Prof. Satish Patil 《Chemistry (Weinheim an der Bergstrasse, Germany)》2016,22(15):5288-5294
This study reports the synthesis and photophysical properties of a star‐shaped, novel, fluoranthene–tetraphenylethene (TFPE) conjugated luminogen, which exhibits aggregation‐induced blue‐shifted emission (AIBSE). The bulky fluoranthene units at the periphery prevent intramolecular rotation (IMR) of phenyl rings and induces a blueshift with enhanced emission. The AIBSE phenomenon was investigated by solvatochromic and temperature‐dependent emission studies. Nanoaggregates of TFPE, formed by varying the water/THF ratio, were investigated by SEM and TEM and correlated with optical properties. The TFPE conjugate was found to be a promising fluorescent probe towards the detection of nitroaromatic compounds (NACs), especially for 2,4,6‐trinitrophenol (PA) with high sensitivity and a high Stern–Volmer quenching constant. The study reveals that nanoaggregates of TFPE formed at 30 and 70 % water in THF showed unprecedented sensitivity with detection limits of 0.8 and 0.5 ppb, respectively. The nanoaggregates formed at water fractions of 30 and 70 % exhibit high Stern–Volmer constants (Ksv=79 998 and 51 120 m ?1, respectively) towards PA. Fluorescence quenching is ascribed to photoinduced electron transfer between TFPE and NACs with a static quenching mechanism. Test strips coated with TFPE luminogen demonstrate fast and ultra‐low‐level detection of PA for real‐time field analysis. 相似文献
33.
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
34.
Poojali P. Warekar Priyanka T. Patil Kirti T. Patil Dattatraya K. Jamale Govind B. Kolekar 《合成通讯》2016,46(24):2022-2030
An ecofriendly route has been investigated for the synthesis of 4-(4-nitro-phenyl)-2-phenyl-1,4-dihydro-benzo[4,5]imidazo[1,2-a]pyrimidine-3-carboxylic acid ethyl ester derivatives by one-pot, three-component condensation of ethyl benzoylacetate, aromatic aldehydes, and 2-amino benzimidazole using 260?mol% of citric acid as reaction mediator. Citric acid is an inexpensive, nontoxic, and green medium with smoothly activates the rate of reaction. The synthesized compounds were assessed for in vitro antimycobacterial activity against Mycobacterium tuberculosis H37RV strain using the microplate alamar blue assay (MABA). The results indicate that among all the synthesized compound series, P-4 and P-9 compounds illustrate effective activity with a minimum inhibitory concentration of 25?µg/ml. 相似文献
35.
Magnetic nanoparticle‐tethered Schiff base–palladium(II): Highly active and reusable heterogeneous catalyst for Suzuki–Miyaura cross‐coupling and reduction of nitroarenes in aqueous medium at room temperature 下载免费PDF全文
K. Manjunatha Tuhin S. Koley Vishal Kandathil Ramesh B. Dateer Geetha Balakrishna B. S. Sasidhar Shivaputra A. Patil Siddappa A. Patil 《应用有机金属化学》2018,32(4)
As a continuation of our efforts to develop new heterogeneous nanomagnetic catalysts for greener reactions, we identified a Schiff base–palladium(II) complex anchored on magnetic nanoparticles (SB‐Pd@MNPs) as a highly active nanomagnetic catalyst for Suzuki–Miyaura cross‐coupling reactions between phenylboronic acid and aryl halides and for the reduction of nitroarenes using sodium borohydride in an aqueous medium at room temperature. The SB‐Pd@MNPs nanomagnetic catalyst shows notable advantages such as simplicity of operation, excellent yields, short reaction times, heterogeneous nature, easy magnetic work up and recyclability. Characterization of the synthesized SB‐Pd@MNPs nanomagnetic catalyst was performed with various physicochemical methods such as attenuated total reflectance infrared spectroscopy, UV–visible spectroscopy, inductively coupled plasma atomic emission spectroscopy, energy‐dispersive X‐ray spectroscopy, field‐emission scanning electron microscopy, transmission electron microscopy, powder X‐ray powder diffraction, thermogravimetric analysis and Brunauer–Emmett–Teller surface area analysis. 相似文献
36.
37.
V. R. Patil D. D. Pawar G. U. Khapekar 《International Journal of Theoretical Physics》2012,51(7):2101-2108
In this paper, we have obtained plane symmetric cosmological models of thick domain walls with viscous field coupled with electromagnetic field in the framework of Lyra geometry, by using equation of state. Physical and geometrical implications of the models are also discussed in the presence of magnetic field. 相似文献
38.
Rapid synthesis of triarylcyanurates (2,4,6-triaryloxy-1,3,5-triazine) was carried out by reacting cyanuric chloride with the sodium salt of hydroxyaryl compounds in water using focused microwaves. Environmentally friendly procedure and isolation of pure products in excellent yields are important features of this method. 相似文献
39.
The exact solution of Einstein-Cartan field equations for static, conformally flat spherically symmetric space-time is derived
and it is proved to be Petrov-type D. 相似文献
40.
T. V. Subramanya Prasad C. R. Shahini Shivaputra A. Patil Xiaojun Huang 《Journal of Coordination Chemistry》2017,70(4):600-614
Various nitro/nitrile-functionalized benzimidazol-2-ylidene carbene complexes of silver(I) (7a–d and 11a–d) were synthesized by combination of 1-allyl/1-isopropyl/1-sec-butyl/1-isopentyl-3-(nitro/cyano-benzyl)-3H-benzimidazol-1-ium hexafluorophosphate (6a–d and 10a–d) with silver(I) oxide in acetonitrile. The compounds were characterized by 1H, 13C NMR, FT-IR, mass spectrometry, and elemental analysis. Additionally, the in vitro antibacterial activity of the N-heterocyclic carbene (NHC) precursors (6a–d and 10a–d) and their corresponding NHC-silver(I) complexes (7a–d and 11a–d) were investigated against Gram-positive bacteria Staphylococcus aureus and Gram-negative bacteria Escherichia coli using the qualitative Kirby-Bauer disk diffusion method. All the NHC-silver(I) complexes exhibited medium-to-high antibacterial activity with areas of clearance ranging from 12 mm to 21 mm, while the NHC precursors were inactive against both strains of bacteria. 相似文献