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81.
A maximum-likelihood (ML) method based on spectral estimation theory for the extraction of dual phase distributions in holographic moire in the presence of nonsinusoidal waveforms, noise, and the miscalibration of piezoelectric (PZT) devices is proposed. The extraction of these phases requires incorporating two PZTs into the moire setup. ML estimators are asymptotically efficient for sufficient data samples. The approach presented uses a direct stochastic algorithm called probabilistic global search Lausanne for minimizing the ML function. 相似文献
82.
83.
Patil ST Bhoir IC Bhagwat AM Sundaresan M 《Fresenius' Journal of Analytical Chemistry》2000,367(1):91-93
Tolnaftate, an antifungal drug (TF) and related impurities arising from synthesis, viz., N-methyl-m-toluidine (NMmT) and beta-naphthol-1-chlorothio carbamate (beta-NCTC) can be determined by supercritical fluid chromatography. Even though it was possible to elute TF completely with neat SCF CO2, the peaks of the impurities were found to merge. The chromatographic figures of merit of the three analytes such as retention time (tR), capacity factor (k), selectivity factor (alpha), no. of theoretical plates (N), were optimized. The three compounds can be resolved in 5 min on a Hypersil (250 x 4.0 mm) 5 mu, C18 column with supercritical carbon dioxide, modified with 1.96% methanol as the mobile phase at 9.81 MPa and at 40 degrees C. Detection was carried out at 220 nm. The data as evaluated by the linear regression least squares fit method gave linearity ranges from 0.2 to 10.0 microg/mL for TF and NMmT and 0.3 to 10.0 microg/mL for beta-NCTC with correlation coefficients > 0.99. The method was successfully employed to estimate levels of 0.01% for NMmT and 0.02% for beta-NCTC with respect to TF. 相似文献
84.
This review focuses mainly on recent endeavors in the field of cyclizations triggered by the catalytic hydroamination (formal or direct) of alkynes. The new strategies developed offer an efficient and convenient entry to several heterocycles of biological importance. 相似文献
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Several constitutive inequalities have been proposed in the literature to quantify the notion that ‘stress increases with strain’ in an elastic material. Due to some inherent shortcomings in them, which we discuss, we propose a new tensorial criterion for isotropic materials. We also present necessary conditions in terms of elasticity tensors for the onset of elastic instabilities. 相似文献
88.
Vishalkumar R. More Umesh S. Mote Shivajirao R. Patil Govind B. Kolekar 《Journal of solution chemistry》2010,39(1):97-106
The binding of riboflavin (RBF) to norfloxacin (NF) was investigated by spectroscopic techniques. The results revealed that
RBF caused the fluorescence quenching of NF by complex formation. The binding parameters and corresponding thermodynamic parameters ΔH, ΔG and ΔS at different temperatures were calculated. The negative enthalpy (ΔH) and positive entropy (ΔS) values indicated that both hydrogen bond and hydrophobic forces played major roles in the binding of RBF to NF. The distance
r between donor (NF) and acceptor (RBF) was obtained according to the Forster’s theory of non-radiative energy transfer. The
method of quenching was successfully applied for the determination of riboflavin from pharmaceutical samples. 相似文献
89.
A. R. Joshi Abhay V. Patil U. M. Kasar 《Journal of Radioanalytical and Nuclear Chemistry》2010,286(1):67-69
Precipitation and solvent extraction methods have been investigated for the purification of plutonium from silver from the
solution generated during oxidative dissolution of plutonium oxide using Ag(II) ions. Initial experiments have been carried
out using thorium as representative of plutonium. Selecting the optimum conditions, the experiments were repeated with plutonium.
The results revealed that Pu can be purified from silver ions either by precipitating silver as silver chloride or silver
metal followed by Pu(IV) oxalate precipitation or by selective extraction of Pu(IV) into 20% Aliquat-336 or 30% TBP. 相似文献
90.
U. S. Mote S. L. Bhattar S. R. Patil G. B. Kolekar 《Journal of solution chemistry》2009,38(5):619-628
The interaction between fluorescein and felodipine (FLD) was investigated by the spectrofluorometric method. The fluorescence
of FLD was quenched by fluorescein and quenching is in accordance with the Stern-Volmer relation. The binding constants of
fluorescein with FLD were obtained at different temperatures. The binding constant and number of binding sites at different
temperatures were calculated yielding the corresponding thermodynamic parameters ΔS, ΔH and ΔG. The distance r between the donor (FLD) and acceptor (fluorescein) molecules was obtained according to the fluorescence resonance energy
transfer. The optimum conditions for the fluorometric determination of fluorescein were studied and the quenching method was
successfully applied to estimate the fluorescein concentration of the pharmaceutical sample directly. 相似文献