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171.
Elegbede AI Haldar MK Manokaran S Mallik S Srivastava DK 《Chemical communications (Cambridge, England)》2007,(43):4495-4497
We report the selective recognition of carbonic anhydrase isozymes based on the excited-state lifetimes of chelated Eu(3+) ions incorporated in polymerized liposomes. 相似文献
172.
The objective of this paper is to explore both grid method and Digital Image Correlation (DIC) technique for microscale and
discontinuous displacement measurements, such as those associated with crack tips. First, the principle of the grid method
is revisited. The grid method and DIC technique are then applied to computer generated images to calculate the displacement
field around crack tips. Finally, the grid method is applied to actual experimental images of fracture tests which are conducted
inside a Scanning Electron Microscope (SEM) chamber. A new technique is developed to generate microscale pattern that is suitable
for both grid method and DIC technique. The displacement fields calculated from grid method are compared with those from DIC
technique to identify the strengths and weaknesses of each technique for the microscale and discontinuous displacement measurements.
It has been determined that grid method can obtain data closer to the discontinuity than DIC; however, DIC produces smoother
displacement fields at the far field. Using this new pattern generation technique, both grid method and DIC technique can
be applied to the fracture test at the microscale to complement with each other to achieve the best experiment results. 相似文献
173.
Krishna Kanta Haldar Dr. Tapasi Sen Sadananda Mandal Prof. Amitava Patra 《Chemphyschem》2012,13(17):3989-3996
We design well‐defined metal‐semiconductor nanostructures using thiol‐functionalized CdTe quantum dots (QDs)/quantum rods (QRs) with bovine serum albumin (BSA) protein‐conjugated Au nanoparticles (NPs)/nanorods (NRs) in aqueous solution. The main focus of this article is to address the impacts of size and shape on the photophysical properties, including radiative and nonradiative decay processes and energy transfers, of Au‐CdTe hybrid nanostructures. The red shifting of the plasmonic band and the strong photoluminescence (PL) quenching reveal a strong interaction between plasmons and excitons in these Au‐CdTe hybrid nanostructures. The PL quenching of CdTe QDs varies from 40 to 86 % by changing the size and shape of the Au NPs. The radiative as well as the nonradiative decay rates of the CdTe QDs/QRs are found to be affected in the presence of both Au NPs and NRs. A significant change in the nonradiative decay rate from 4.72×106 to 3.92×1010 s?1 is obtained for Au NR‐conjugated CdTe QDs. It is seen that the sizes and shapes of the Au NPs have a pronounced effect on the distance‐dependent energy transfer. Such metal‐semiconductor hybrid nanostructures should have great potentials for nonlinear optical properties, photovoltaic devices, and chemical sensors. 相似文献
174.
175.
A method is described for the substoichiometric determination of traces of palladium by neutron activation analysis involving
the extraction of palladium with isonitrosoacetophenone. The sensitivity of the method is 0.005 μg of Pd. With 200 mg of silver
alloy containing 0.0005% palladium, the average of three determinations of Pd is 0.98 μg, which varies between 1.07 μg and
0.91 μg at 95% confidence limit. The time required for radiochemical purification and counting of the sample does not exceed
12 minutes.
Part of this work was presented at the International Conference on Modern Trends Activation Analysis, held in Gaithersburg,
Maryland, USA, October 7–11, 1968. 相似文献
176.
A rapid and simple method has been developed for the determination of Mn, Zn, Cr and Ag by radiochemical thermal neutron activation analysis, involving solvent extraction and precipitation technique. Mn, Zn, Cr and Ag can be determined with an accuracy of 8.9, 5.8, 7.7 and 7.6%, respectively. The method has been employed for determination of the elements in fish solubles. Two samples and a standard can be analyzed in three hours. 相似文献
177.
P.H. Umadikar S.G. Mestry N.V. Bhat B.C. Haldar 《Spectrochimica Acta Part B: Atomic Spectroscopy》1976,31(7):411-417
X-ray K-absorption edge of nickel in some nickel (II) complexes has been investigated using a 400-mm bent crystal spectrometer. The structure associated with the absorption edge has been used to deduce information regarding the bond lengths, the mode of bonding and the co-ordination of Ni(II) in the complexes. On the basis of the results obtained, it has been concluded that in the two forms of Ni(INAP)2 (green and brown) the Ni(II) ions are surrounded by distorted octahedra whereas Ni(II) ions in Ni(C6H9N2O3)2 has a square planar structure. Ni(αBMO)2 appears to have NiNi type metallic interaction. 相似文献
178.
Thamarai Devarajan Seiichiro Higashiya Christopher Dangler Manisha Rane-Fondacaro Jeremy Snyder Pradeep Haldar 《Electrochemistry communications》2009,11(3):680-683
A novel oxygen containing spiro ammonium salt, oxazolidine-3-spiro-1’-pyrrolidinium tetrafluoroborate (OPBF4) was synthesized using an innovative technique for use as electrolyte in electrochemical double layer capacitors (EDLC). Comparison of OPBF4 with commercially available, tetraethyl ammonium tetrafluoroborate (TEABF4) showed higher voltage window and higher capacitance for the OPBF4 compound. Moreover, molarity of 3 M was produced with OPBF4 as compared to a maximum of 1.5 M for TEABF4 in acetonitrile (AN). This is especially important to enable the fabrication of higher energy density EDLC. This is the first report of testing OPBF4 compound in an EDLC device, and it qualifies as a reasonable alternative to TEABF4 for high performance ultracapacitors. 相似文献
179.
A simple and rapid substoichiometric method for the determination of small amounts of molybdenum in steel by neutronactivation analysis is based on the extraction of molybdenum alpha-benzoinoximate into chloroform. The sensitivity of the method is 0.2 microg and the relative standard deviation is 1%. Two activated samples can be processed and counted within 30 min. 相似文献
180.
Mallick A Haldar B Chattopadhyay N 《Journal of photochemistry and photobiology. B, Biology》2005,78(3):215-221
Steady state absorption and fluorometric techniques have been used to investigate the photophysics of norharmane (NHM), a bioactive fluorophore, in aqueous as well as aqueous cyclodextrin (CD) environments. The absorption and steady state fluorescence spectral studies reveal the formation of two types of inclusion complexes between the fluorophore and beta-cyclodextrin (beta-CD) depending on the relative population of the two. The stoichiometries and association constants of these complexes have been determined monitoring the fluorescence data. alpha-and gamma-cyclodextrin (alpha-CD, gamma-CD) do not have appreciable effect on the spectral pattern of the fluorophore. The differential fluorimetric behavior of NHM in different CD environments has been rationalized from the variation of the relative dimensions of the probe and the CD cavities. 相似文献