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101.
A. Sarkar Shweta Hegde T. Mukherjee S. Kapoor 《Research on Chemical Intermediates》2010,36(3):309-318
The effect of silver ions and silver nanoparticles on the rate of polymerization of acrylamide and N-isopropylacylamide was investigated. Composites of silver particles of diameter around 30 nm and polyacrylamide were prepared
by the photochemical method in the absence of any photosensitizer. The particles formed were characterized by UV–visible spectrophotometry,
XRD, and TEM. It was shown that the presence of metal ions such as Ag+, Co2+, and Ni2+ in the acrylamide monomer is essential for photoinduced polymerization. 相似文献
102.
Anoop M Saxena G Krishnamoorthy Jayant B Udgaonkar N Periasamy 《Journal of Chemical Sciences》2007,119(2):61-69
In protein-folding studies it is often required to differentiate a system with only two-states, namely the native (N) and
unfolded (U) forms of the protein present at any condition of the solvent, from a situation wherein intermediate state(s)
could also be present. This differentiation of a two-state from a multi-state structural transition is non-trivial when studied
by the several steady-state spectroscopic methods that are popular in protein-folding studies. In contrast to the steady-state
methods, time-resolved fluorescence has the capability to reveal the presence of heterogeneity of structural forms due to
the ‘fingerprint’ nature of fluorescence lifetimes of various forms. In this work, we establish this method by quantitative
analysis of amplitudes associated with fluorescence lifetimes in multiexponential decays. First, we show that we can estimate,
accurately, the relative population of species from two-component mixtures of non-interacting molecules such as fluorescent
dyes, peptides and proteins. Subsequently, we demonstrate, by analysing the amplitudes of fluorescence lifetimes which are
controlled by fluorescence resonance energy transfer (FRET), that the equilibrium folding-unfolding transition of the small
single-domain protein barstar is not a two-step process. 相似文献
103.
Subramanya Gopal Hegde Lokesh Koodlur Suman Y. Reddy Manjunatha Narayanarao 《中国化学会会志》2019,66(12):1708-1712
Employment of metal nanoparticles has been one of the most promising synthetic strategies for a number of chemical transformations. New spiroindane‐1,3‐diones were synthesized through [3 + 2] cycloaddition in moderate to high yields by a three‐component reaction of heterocyclic chalcone derivatives, ninhydrin, and sarcosine/L‐proline. The presence of heterogenous MgSiO3 nanoparticles (NPs) under microwave irradiation showed a robust effect in improving the yield of the desired products. Furthermore, the catalyst may be recovered and reused without significant loss of activity. 相似文献
104.
Subbaiah Yogesha Kumar Arun Sharankumar G. Shetty Hegde Ravi Narayana Ramesh 《Journal of separation science》2019,42(2):484-490
A new liquid chromatography with tandem mass spectrometry method employing a mixed‐mode zwitterionic stationary phase was developed for simultaneous determination of urease inhibitor (N‐butylthiophosphoric triamide) and nitrification inhibitor (dicyandiamide) in urea fertilizer. Molecular modeling based on density functional theory calculations was employed to provide an insight into the interaction mechanism of urea, dicyandiamide, and N‐butylthiophosphoric triamide with zwitterionic stationary phase in chromatographic separation system. The detection of analytes was performed on a triple quadrupole tandem mass spectrometer in multiple reaction monitoring mode using positive electrospray ionization. The ion transitions monitored were m/z 85→68 for dicyandiamide and m/z 168.2→74 for N‐butylthiophosphoric triamide, respectively. The standard calibration curves of dicyandiamide and N‐butylthiophosphoric triamide were linear over the range of 1.0 ? 15 ppm (coefficient of determination = 0.9984), 0.05 ? 1 ppm (coefficient of determination = 0.9995), with limit of detection of 25 and 5 ppb, respectively. The recoveries of low, middle, and high concentrations were from 96.7 to 105.8% for N‐butylthiophosphoric triamide and 94.4 to 105.8% for dicyandiamide with accuracy (relative error %) of ≤5.8% and ≤5.8%, the precision (coefficients of variation) was ≤2.0% and ≤2.9%, respectively. The validated method was successfully applied on real urea samples to determine N‐butylthiophosphoric triamide and dicyandiamide simultaneously. 相似文献
105.
A green synthesis of 1,2,3-triazolyl-pyridine hybrids and evaluation of their antibacterial activity
106.
107.
P. Poornesh Pramod K. Hegde M.G. Manjunatha A.V. Adhikari 《Optics & Laser Technology》2010,42(1):230-989
An experimental investigation of the third-order nonlinear optical properties of new poly{2-{5-[3,4-ditetradecyloxy-5-(1,3,4-oxadiazol-2-yl)thiophen-2-yl]-1,3,4-oxadiazol-2-yl}pyridine} (P) in tetrahydrofuran (THF) solution and in solid poly(methylmethacrylate) (PMMA) matrix, by Z-scan technique is reported. The Z-scan traces reveal that the composite films exhibit large negative nonlinear refractive index of the order 10−10 esu. The excited-state absorption cross-section was found to be larger than the ground-state absorption indicating that the operating nonlinear process is reverse saturable absorption (RSA). The new polymer P exhibits good optical power limiting properties in the nanosecond regime in solution and as well in solid PMMA matrix. 相似文献
108.
An end-to-end assembly of spherical Ag nanoparticles takes place in the presence of biotin to form long fiberlike microstructures. These microstructures are about 4 mum long with a thickness of 1 mum, obtained from SEM studies. TEM studies showed the presence of spherical silver nanoparticles having an average size of 20 nm. ATR-FTIR studies revealed that silver ions interact with biotin involving the carboxylate group. A weak binding of the silver particles with the thioether and ureido groups helps in connecting the Ag nanoparticles to form long fiberlike structures. Elucidation of the mechanism of formation of the spherical Ag clusters was done by pulse radiolysis. 相似文献
109.
Carrillo LD Krishnamoorthy L Mahal LK 《Journal of the American Chemical Society》2006,128(46):14768-14769
beta-O-N-Acetyl-d-glucosamine (O-GlcNAc) is a dynamic carbohydrate modification that is involved in cell signaling and has been implicated in a variety of disease states, including Alzheimer's and type-II diabetes. Despite the importance of this modification, little is known about the spatial and temporal localization of O-GlcNAc during signaling. This is due to the lack of methods for the study of O-GlcNAc in living cell systems. Herein we report the first genetically encoded FRET-based sensor for the detection of O-GlcNAc dynamics in live mammalian cells. 相似文献
110.
A T Ernst M Horn P Kilby M Krishnamoorthy 《The Journal of the Operational Research Society》2010,61(7):1133-1143
The rental fleet scheduling problem (RFSP) arises in vehicle-rental operations that offer a wide variety of vehicle types to customers, and allow a rented vehicle to ‘migrate’ to a setdown depot other than the pickup depot.When there is a shortage of vehicles of a particular type at a depot, vehicles may be relocated to that depot, or vehicles of similar types may be substituted.The RFSP involves assigning vehicles to rentals so as to minimise the costs of these operations, and arises in both static and online contexts. The authors have adapted a well-known assignment algorithm for application in the online context. In addition, a network-flow algorithm with more comprehensive coverage of problem conditions is used to investigate the determination of rental pricing using revenue management principles. The paper concludes with an outline of the algorithms’ use in supporting the operations of a large recreational vehicle rental company. 相似文献