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1.
In this study, the urea dynamics inside AOT reverse micelle (RM) has been monitored without intervention of water using time-resolved fluorescence techniques from the picosecond to nanosecond time regime. It has been observed that urea dynamics inside the reverse micelle is severely retarded compared to water RM due to the formation of highly networked urea cluster inside the RM. Time-resolved fluorescence anisotropy study also confirms the existence of a confined environment around the dye at higher concentrations of urea inside the reverse micelle. The dynamics of urea-water mixtures inside AOT reverse micelle has also been monitored with increasing urea concentration to get insight about the effect of urea on the overall solvation dynamics feature. It has been observed that with the increase in urea concentration, the overall dynamics becomes slower, and it infers the presence of few water or urea molecules, those strongly associated with surrounding urea and (or) water by hydrogen bonds. 相似文献
2.
Photocleavable protecting groups are important in synthesis and caging. Among many such groups, 2-nitrobenzyl and related groups have been found useful in many applications. However, most of the known 2-nitrobenzyl-based caging chromophores show either low quantum yield or the photolysis wavelength is not suitable for various applications. In this paper, we report 2-nitro-3-naphthalenemethanol (NNM) as an efficient photocleavable protecting group for molecules containing a carboxylic function. NNM possesses photochemical properties better than the 2-nitrobenzyl chromophores as it is photoactivatable at 380 nm in aqueous medium (CH3CN/H2O, 3:2 v/v) showing the desired photochemistry. The carboxylic acids are efficiently photoreleased from NNM-based esters in almost quantitative yield. 相似文献
3.
We consider a collapsing spherically symmetric inhomogeneous dust cloud in higher dimensional space-time. We show that the
central singularity of collapse can be a strong curvature or a weak curvature naked singularity depending on the initial density
distribution. 相似文献
4.
Manik Waghmare Bipin Khade Pradip Chaudhari Prabhakar Dongre 《Journal of nanoparticle research》2018,20(7):185
It is well known that when nanoparticles (NPs) are exposed to biological fluid, it results into formation of nanoparticle protein corona, which has been the subject of extensive studies for the development of targeted drug delivery. In this work, we demonstrated the dynamic light scattering, fluorescence, and UV-visible spectroscopy as quantitative and qualitative tools to monitor adsorption of BSA protein onto silver nanoparticles (AgNPs). The adsorption resulted in significant gradual increase in average hydrodynamic radius of BSA-AgNP corona from 24 to 35 nm and its attainment of equilibrium point (saturation) that correlated with albumin concentration enables condition for bound and unbound protein adsorption to be interpreted. Using DLS, the dissociation constant (KD) was obtained for soft corona to be 2.09?±?0.30 μM. The UV-visible and fluorescence spectroscopy results were correlated with DLS. Loss of percent helicity in secondary structure of adsorbed BSA was monitored in both coronas as compared to native protein. Both coronas were found to be biocompatible with RBC membrane. Further, the results of adsorption isotherm model were used to validate the multilayer formation of albumin protein on silver nanoparticles. The obtained results would be relevant in the drug design development for tumor-targeted therapy. 相似文献
5.
The scattering of incident plane elastic waves by a varietyof different defects that lie upon a fluid-solid interface isconsidered here using matched asymptotic expansions. The expansionscheme is developed in terms of a parameter , the ratio of typicaldefect length scale to a typical wavelength of the incidentfield, taken to be small. Three different canonical situations occur and these are illustratedvia three specific examples treated here: a rigid strut, anedge crack, and a rigid strip. In each case the leading-ordermatching is performed to identify the leading-order contributionof the defect to the acoustic field in the far field. In particular,each defect is identified with a source of dipole response ininterfacial stress of displacement. It is shown in the limit as s<<s1 that in the inner problemsthe fluid and solid pieces uncouple in a particularly convenientmanner allowing analytical solutions to be deduced. These arethen matched with appropriate outer solutions. 相似文献
6.
Freneil B. Jariwala John A. Hibbs Carl S. Weisbecker John Ressler Rahul L. Khade Yong Zhang Athula B. Attygalle 《Journal of the American Society for Mass Spectrometry》2014,25(9):1670-1673
We describe a diagnostic ion that enables rapid semiquantitative evaluation of the degree of oxygen contamination in the collision gases used in tandem mass spectrometers. Upon collision-induced dissociation (CID), the m/z 359 positive ion generated from the analgesic etoricoxib undergoes a facile loss of a methyl sulfone radical [?SO2(CH3); 79-Da] to produce a distonic radical cation of m/z 280. The product-ion spectrum of this m/z 280 ion, recorded under low-energy activation on tandem-in-space QqQ or QqTof mass spectrometers using nitrogen from a generator as the collision gas, or tandem-in-time ion-trap (LCQ, LTQ) mass spectrometers using purified helium as the buffer gas, showed two unexpected peaks at m/z 312 and 295. This enigmatic m/z 312 ion, which bears a mass-to-charge ratio higher than that of the precursor ion, represented an addition of molecular oxygen (O2) to the precursor ion. The exceptional affinity of the m/z 280 radical cation towards oxygen was deployed to develop a method to determine the oxygen content in collision gases. Figure
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7.
Photoexcitation of a solution of anthracene-9-methanol derived esters at ∼386 nm in CH3CN/H2O (3:2 v/v) results in fluorescence emission in the 380-480 nm range, with quantum yields of fluorescence (Φf) in the 0.01-0.09 range and releases of the carboxylic acids in good chemical yields (43-100%), with quantum yields of photoreaction (ΦPR, i.e., the photodisappearance of the esters) in the 0.067-0.426 range. 相似文献
8.
Santosh M. Surwase Yogesh D. Mane Mahesh M. Surwase Bhimrao C. Khade 《Journal of heterocyclic chemistry》2020,57(2):724-730
A series of (E)-2-((1H-imidazol-1-yl)methyl)-2-((benzyloxy)methyl)-2,3-dihydro-1H-inden-1-one O-benzyl oximes ( 6a-j ) were prepared and evaluated for their in vitro antileishmanial potency against Leishmania donovani (in promastigote and amastigote models). At a concentration of 05-μg/mL, compounds 3a-d , 4a-d , 5a , 5b , 6a-d, and 7a-d exhibited 97% to 100% and 87% to 100% inhibition against promastigotes and amastigotes, respectively. Compounds 6a , 6d-6j and 6a , 6i , 6j exhibited equal antileishmanial potency to that of SSG and Pentamidin at lower values of IC50. 相似文献
9.
AbstractA simple, efficient, solventless, and one step, B(C6F5)3 catalyzed, synthesis of dihydropyrano[3,2-b]chromenediones from dimedone, aldehyde and kojic acid is described. This protocol proceeds smoothly, accommodates aromatic as well as heteroaromatic aldehydes and gives dihydropyrano[3,2-b]chromenediones in excellent yield. 相似文献
10.
Design,synthesis, and antimicrobial activity of novel 5-substituted indole-2-carboxamide derivatives
Mane Yogesh D. Sarnikar Yuvaraj P. Surwase Santosh M. Biradar Dhanraj O. Gorepatil Pratapsinha B. Shinde Vishnu S. Khade Bhimrao C. 《Research on Chemical Intermediates》2017,43(2):1253-1275
Research on Chemical Intermediates - A series of novel, bioactive 5-substituted indole-2-carboxamide derivatives (10a–t and 14a–k) are synthesized by the coupling of 5-substituted... 相似文献