Wavelet filtering applied to time-average digital speckle pattern interferometry fringes

In this paper we are presenting a filtering scheme using Symlet wavelet to remove the speckle noise from the time-averaged digital speckle pattern interferometry fringes. To demonstrate the potential of Symlet wavelet filtering, experiments are conducted to remove the speckle noise from the fringes recorded for the surface of computer hard disk. Experimental results demonstrate that this filtering removes the speckle noise to the large extent.     

Integrals involving Fox’sH-function

We evaluate four integrals involving Fox’sH-functions and a general class of polynomialsS _n ^m [x], introduced earlier by Srivastava.     

Anodic Synthesis of New Benzofuran Derivatives Using Active Methylene Group at Platinum Electrode

A facile and Eco-compatible synthesis of benzofuran derivatives (4a–4h) has been carried out at platinum electrode by electrochemical oxidation of catechol in the presence of active methylene groups. Electro- organic synthesis has been performed in an undivided cell at ambient conditions. The products of electrolysis have been purified and characterized by FTIR, ¹H NMR and ¹³C NMR and mechanism was deduced by voltammetric studies.     

Effect of flow and surface conditions on human lymphocyte isolation using microfluidic chambers

Phenotypically pure subpopulations of lymphocytes can provide valuable insights into the immune response to injury and disease. The isolation of these subpopulations presents unique challenges, particularly when preprocessing incubation to attach fluorescent or antibody tags is to be minimized. This paper examines the separation of T and B lymphocytes from mixtures using microfluidic chambers coated with antibodies, focusing on flow conditions and surface chemistry. The adhesion of both cell types decreases as shear stress increases irrespective of the surface chemistry. The incorporation of poly(ethylene glycol) chains along with the antibodies on the chamber surface is shown to significantly improve the reproducibility of cell adhesion and is thus an important part of the overall system design. Furthermore, this technique is shown to be an effective way of isolating highly pure subpopulations of lymphocytes from model mixtures, even when the target cell concentration is low.     

3-Methyl-4-amino-5-mercapto-1,2,4-triazole as a ring-colorimetric reagent for the selective microevaluation of Au(III), Ti(I), and Ag(I)

MAMT has been studied for its microanalytical uses. Selective microevaluation of Au(III), Ag(I), and Tl(I) have been carried out with MAMT, incorporating masking and solvent extraction techniques in conjunction with ring colorimetry. MAMT has also been used as a chromogenic reagent for Au(III), while PTC had to be used for Ag(I) and Tl(I) as their MAMT complexes are white.     

Experimental investigations of thermal stability of some morpholinecarbamic acid complexes of copper(II) and zinc(II)

Some new carbamates, viz. M(MorphcbmH)₂X₂ (MorphcbmH = morpholinecarbamic acid, M = Cu, X = Cl, ClO₄,NO₃; M = Zn, X = Cl, ClO₄, NO₃, CH₃COO and X₂ = SO₄), have been synthesized and investigated. Compounds were characterized by elemental analysis, molar conductance, FT infrared, fluorescence, NMR (¹H and ¹³C) and solution electronic absorption spectral studies. Room temperature field-dependent magnetic susceptibility measurements, PXRD spectral and cyclic voltametric studies were also conducted. Chelating bidentate mode of coordination of ligand, MorphcbmH with four coordination around metal ion has been proposed. Ligand and its compounds have also been studied using non-isothermal thermogravimetric analysis and differential scanning calorimetric analytical techniques which inferred formation of metal oxide/MCO₃ as final thermal decomposition products. Compounds were screened against the lipase enzyme for assaying their enzyme activity and were found to retard the lipase activity from 48.16 to 0.044 µmol mL^?1 min^?1.     

Synthesis and Crystal Structure of Thiazolopyrimidine Derivatives: Insights into Weak Interactions

Crystallography Reports - Thiazolo[3,2-a]pyrimidines namely ethyl 2-acetyl-5-(2-fluorophenyl)-3,7-dimethyl-5H-thiazolo[3,2-a]pyrimidine-6-carboxylate 3a, ethyl...     

Strong mechanoluminescence induced by elastic deformation of rare-earth-doped strontium aluminate phosphors

When rare-earth-doped strontium aluminate phosphor mixed in an epoxy resin, is deformed elastically by applying a uniaxial pressure, then initially the mechanoluminescence (ML) intensity increases with time, attains a peak value I_m at a particular time t_m, and later on it decreases with time. After t_m, initially, the ML intensity decreases exponentially at a fast rate and then it decreases exponentially at a slow rate. The ML appears after a threshold pressure and then, initially at low pressure, the peak intensity I_m of ML increases linearly with the magnitude of applied pressure, and for high pressure, I_m increases exponentially with the magnitude of applied pressure. The value of I_m increases linearly with the density of filled hole traps. The ML emission also takes place during the release of applied pressure. There should be a significant effect of temperature on the ML intensity of rare-earth-doped strontium aluminate phosphors. The ML intensity of rare-earth-doped strontium aluminates decreases with successive number of the applications of pressure and the diminished ML intensity can be recovered with the exposure of the samples to UV-radiation. The ML spectra of rare-earth-doped strontium aluminate phosphors are similar to their photoluminescence spectra. As only the piezoelectric-phase of the strontium aluminate phosphors exhibit ML during their elastic deformation, the ML emission can be attributed to the piezoelectrification of the crystals. Considering that the piezoelectric field causes decrease in the trap-depth of the hole traps and, therefore, the holes transferred from traps to the valence band recombine with (Eu¹⁺)^* ions, whereby the Eu²⁺ ions are excited, expressions are derived for different parameters of ML, which are able to satisfactorily explain the experimental results. It is shown that the lifetimes of holes in the shallow traps in stressed and unstressed materials, and the threshold pressure P_t for the ML emission, and other parameters of the ML, can be determined from the ML measurements. Finally, the criteria for tailoring strong elasico-mechanoluminescent materials are explored.     

Functionalized chiral vinyl aminosulfoxonium salts: asymmetric synthesis and application to the synthesis of enantiopure unsaturated prolines, beta,gamma-dehydro amino acids, and cyclopentanoid keto aminosulfoxonium ylides

Methylation of the enantiopure functionalized vinyl sulfoximines 5a-e and 14a-d followed by a F- ion or DBU-mediated isomerization of the vinyl aminosulfoxonium salts 7a-e and 15a-d, respectively, gave the allyl aminosulfoxonium salts 10a-e and 17a-d, respectively. A concomitant intramolecular substitution of the aminosulfoxonium group of 10a-e and 17a-d by the amino group afforded the unsaturated prolines 8a-e and 18a-d, respectively. The starting vinyl sulfoximines are accessible through a highly selective and stereo-complementary aminoalkylation of the corresponding sulfonimidoyl-substituted mono- and bis(allyl)titanium complexes with the imino ester 4. The vinyl aminosulfoxonium salts 34, 7a-d, and E-15c experienced upon treatment with the Cl- ion a migratory substitution with formation of the delta-chloro-beta,gamma-dehydro amino acids 36, E/Z-37a-d, and 38, respectively. A migratory substitution of the hydroxy-substituted vinyl aminosulfoxonium salts 46a and 46b furnished the delta-chloro allyl alcohols E/Z-48a and E-48b, respectively. A facile one-pot conversion of the vinyl sulfoximines 31b, 5c and 45a to the allyl chlorides 36, E/Z-37c and E/Z-48a, respectively, was achieved upon treatment with a chloroformiate. A tandem cyclization of the vinyl aminosulfoxonium salts 7b, Al-7b and 57 with LiN(H)tBu yielded the cyclopentanoid keto aminosulfoxonium ylides 54, Al-54, 59, 60 and 61, respectively. The structure of the tricyclic keto aminosulfoxonium ylide Al-54 has been determined by X-ray crystal structure analysis. Ab initio calculations and a NBO analysis of the tricyclic keto aminosulfoxonium ylide XXIII show a polar structure stabilized by electrostatic interactions between the ylidic C atom and both the carbonyl C atom and the S atom.     

On the role of the counter-ion in defining water structure and dynamics: order, structure and dynamics in hydrophilic and hydrophobic gadolinium salt complexes

The crystal structures of the hydrated salts of [Gd.DOTAM]3+ and its more hydrophobic derivative [Gd.]3+, bearing 4 alpha-phenylethyl groups, (both Gd and Yb salts) are reported and compared. The nature of the anion determines the degree of ordering in the lattice and the extent of hydration. These effects are correlated with the results of 17O and 1H NMR measurements of water exchange dynamics in solution. With [Gd.DOTAM]3+, structural ordering or the extent of hydration in the hydrated lattice follows the sequence Cl->Br->I- and this order also defines the water exchange rate in solution: 7.3, 19.5, 33.3x10(4) s-1 (298 K), respectively. For [Gd.]3+ salts, the measured relaxivity is determined purely by the outer sphere term and the water exchange rate at 298 K is very similar (typically 1x10(4) s-1) for chloride, bromide, iodide, acetate, triflate and nitrate salts, notwithstanding the different nature and extent of hydration found in the crystalline lattice.