The Experts below are selected from a list of 31662 Experts worldwide ranked by ideXlab platform
S Kumararaman - One of the best experts on this subject based on the ideXlab platform.
-
studies on the growth aspects of semi organic cadmium zinc thiourea acetate a promising new nlo crystal
Materials Letters, 2008Co-Authors: K Kirubavathi, N Vijayan, K Selvaraju, R Valluvan, S KumararamanAbstract:Single crystals of a new nonlinear optical material, cadmium zinc thiourea acetate (CZTA), were successfully grown by slow evaporation of the aqueous solution at room temperature. Single crystal X-Ray Diffraction Pattern and FTIR spectrum analysis have confirmed the formation of the new crystal. The optical transmission studies and second harmonic generation (SHG) efficiency studies justified the device quality of the grown crystals.
-
growth and characterization of a new metal organic crystal potassium thiourea bromide
Materials Letters, 2001Co-Authors: K Selvaraju, R Valluvan, S KumararamanAbstract:Single crystals of potassium thiourea iodide (PTI), a semiorganic nonlinear optical crystal, have been grown from low temperature solution growth method by a slow evaporation technique at room temperature. Single crystal X-Ray Diffraction Pattern and FTIR spectrum analysis has confirmed the formation of the new crystal. PTI has good optical transmission in the entire visible region, which is an essential requirement for a nonlinear crystal.
K Selvaraju - One of the best experts on this subject based on the ideXlab platform.
-
studies on the growth aspects of semi organic cadmium zinc thiourea acetate a promising new nlo crystal
Materials Letters, 2008Co-Authors: K Kirubavathi, N Vijayan, K Selvaraju, R Valluvan, S KumararamanAbstract:Single crystals of a new nonlinear optical material, cadmium zinc thiourea acetate (CZTA), were successfully grown by slow evaporation of the aqueous solution at room temperature. Single crystal X-Ray Diffraction Pattern and FTIR spectrum analysis have confirmed the formation of the new crystal. The optical transmission studies and second harmonic generation (SHG) efficiency studies justified the device quality of the grown crystals.
-
growth and characterization of a new metal organic crystal potassium thiourea bromide
Materials Letters, 2001Co-Authors: K Selvaraju, R Valluvan, S KumararamanAbstract:Single crystals of potassium thiourea iodide (PTI), a semiorganic nonlinear optical crystal, have been grown from low temperature solution growth method by a slow evaporation technique at room temperature. Single crystal X-Ray Diffraction Pattern and FTIR spectrum analysis has confirmed the formation of the new crystal. PTI has good optical transmission in the entire visible region, which is an essential requirement for a nonlinear crystal.
Hiroyuki Iwamoto - One of the best experts on this subject based on the ideXlab platform.
-
The 3D structure of fibrous material is fully restorable from its X-Ray Diffraction Pattern
'International Union of Crystallography (IUCr)', 2021Co-Authors: Hiroyuki IwamotoAbstract:X-Ray fiber Diffraction is potentially a powerful technique to study the structure of fibrous materials, such as DNA and synthetic polymers. However, only rotationally averaged Diffraction Patterns can be recorded and it is difficult to correctly interpret them without the knowledge of esoteric Diffraction theories. Here we demonstrate that, in principle, the non-rotationally averaged 3D structure of a fibrous material can be restored from its fiber Diffraction Pattern. The method is a simple puzzle-solving process and in ideal cases it does not require any prior knowledge about the structure, such as helical symmetry. We believe that the proposed method has a potential to transform the fiber Diffraction to a 3D imaging technique, and will be useful for a wide field of life and materials sciences
-
x ray Diffraction Pattern from the flight muscle of toxorhynchites towadensis reveals the specific phylogenic position of mosquito among diptera
Zoological Letters, 2015Co-Authors: Hiroyuki IwamotoAbstract:The Diptera are a group of insects with only a single pair of wings (forewings), and are considered monophyletic (originating from a common ancestor). The flight muscle in Diptera has features not observed in other insects, such as the long Pro-Ala-rich peptide associated with tropomyosin, not with troponin-I as in other insects, and the formation of a superlattice by myosin filaments analogous to that in vertebrate skeletal muscle. Here we describe X-Ray Diffraction Patterns from the flight muscle of a mosquito, Toxorhynchites towadensis (Culicidae), belonging to a primitive group of Diptera. The Diffraction Pattern indicates that myosin filaments in the flight muscle of this species do not form a superlattice. X-Ray Diffraction also shows meridional reflections that are not observed in other dipterans, but are present in the Patterns from bumblebee (Hymenoptera) flight muscle. These observations suggest that the superlattice structure evolved after the common ancestor of Diptera had diverged from other insects. The flight muscle of mosquito may retain primitive structural features that are shared by Hymenoptera.
-
a peculiar meridional reflection in the x ray Diffraction Pattern from dipteran flight muscle suggests an alternating arrangement of tropomyosin isoforms
Biophysical Journal, 2009Co-Authors: Hiroyuki IwamotoAbstract:The X-Ray Diffraction Pattern from the flight muscle of a cranefly, Ctenacroscelis mikado (Diptera), exhibits a prominent meridional reflection not observed in Lethocerus at a spacing of 25.8 nm. Since this spacing is two thirds of the pseudo-repeat of the long-pitched actin helix (38.7 nm), the reflection is likely to be of thin filament-origin. Its occurrence is fully explained if the scattering objects have a basic axial repeat of 77.4 nm (= 2 x 38.7 nm), and the six thin filaments surrounding a thick filament are arranged with an axial stagger of 25.8 nm (= 77.4/3).A possible mechanism to create the 77.4-nm repeat is the presence of two different tropomyosin isoforms. Dipteran flight muscle is known to express usual (∼35 kDa) and heavy (∼80 kDa) tropomyosin isoforms, and the extra mass of the latter is ascribed to the C-terminal extension of a pro- and ala-rich sequence. Tropomyosin is a uniform alpha-helical protein that forms a dimer with a typical coiled-coil structure, but the mass of the C-terminal extension would be localized. Thus, the reflection is most readily explained if the two isoforms produce an alternating array of homodimers. However, a cross-linking study suggests that the Ctenacroscelis isoforms produce heterodimers. In Drosophila, two heavy isoforms are known to exist (TmH-33 and TmH-34), and glutathione S-transferase-2 is stably associated with them (Clayton et al., 1998). Then an alternative explanation is that these isoforms also exist in Ctenacroscelis, and they are alternately arranged and only one of them binds GST-2. The scattering object remains to be identified, but the alternating arrangement of tropomyosin isoforms is the most conceivable mechanism to provide the periodicity needed to create the peculiar meridional reflection.
R Valluvan - One of the best experts on this subject based on the ideXlab platform.
-
studies on the growth aspects of semi organic cadmium zinc thiourea acetate a promising new nlo crystal
Materials Letters, 2008Co-Authors: K Kirubavathi, N Vijayan, K Selvaraju, R Valluvan, S KumararamanAbstract:Single crystals of a new nonlinear optical material, cadmium zinc thiourea acetate (CZTA), were successfully grown by slow evaporation of the aqueous solution at room temperature. Single crystal X-Ray Diffraction Pattern and FTIR spectrum analysis have confirmed the formation of the new crystal. The optical transmission studies and second harmonic generation (SHG) efficiency studies justified the device quality of the grown crystals.
-
growth and characterization of a new metal organic crystal potassium thiourea bromide
Materials Letters, 2001Co-Authors: K Selvaraju, R Valluvan, S KumararamanAbstract:Single crystals of potassium thiourea iodide (PTI), a semiorganic nonlinear optical crystal, have been grown from low temperature solution growth method by a slow evaporation technique at room temperature. Single crystal X-Ray Diffraction Pattern and FTIR spectrum analysis has confirmed the formation of the new crystal. PTI has good optical transmission in the entire visible region, which is an essential requirement for a nonlinear crystal.
Melgardt M De Villiers - One of the best experts on this subject based on the ideXlab platform.
-
preparation and transformation of true nifedipine polymorphs investigated with differential scanning calorimetry and x ray Diffraction Pattern fitting methods
Journal of Pharmaceutical Sciences, 2011Co-Authors: Driekus Grooff, Wilna Liebenberg, Melgardt M De VilliersAbstract:ABSTRACT: The amorphous → metastable and metastable → stable crystalline phase transitions of nifedipine and their relationship with polymorph composition during storage at controlled temperature/humidity conditions were investigated. Metastable form C was produced from both differential scanning calorimetry (DSC) thermal treatment and storage [22°C/0% and 75% relative humidity (RH)] of the amorphous form. Amorphous conversion rate accelerated with storage temperature up to 40°C, but a further 8°C increase to 48°C (3°C above the glass transition) resulted in a more than 12-fold decrease in amorphous conversion rate. DSC and X-Ray Diffraction (XRD) analysis revealed a faster amorphous conversion rate relative to the metastable crystal transformation with 75% RH having a greater accelerative effect on the former. Relative phase quantification from XRD Pattern fitting included the use of integrated peak intensities of the crystalline phases, Rietveld and the Rietveld-based partial or no known crystal structures method. Kinetic analysis with Johnson–Mehl–Avrami equation indicated that the accelerated amorphous conversion in 75% RH was associated with a 10-fold increase in rate constant with dimensional growth little affected. The smaller rate increase for metastable crystal conversion was associated with an increased dimensional growth while the rate constant was little affected.
