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Three-Dimensional Evaluation of Paper Surfaces Using Confocal Microscopy
Published in Terrance E. Conners, Sujit Banerjee, Surface Analysis of Paper, 2020
Marie-Claude Béland, Patrice J. Mangin
Figure 1 illustrates the confocal principle for the Leica CLSM configuration. An argon ion laser provides an intense and stable light source, with a wavelength range of 488 nm to 514.5 nm. At the light source, a pinhole of fixed size is used to obtain point source illumination. The light passing through the objective and reflected from the object is directed at the detector by a beam splitter. A variable-size pinhole in front of the detector allows only reflected light from the focal spot on the object to reach the detector. A point-by-point image is obtained by scanning the beam over an XY plane. The XY image thus obtained has a limited thickness in the Z direction which depends on the opening of the detector pinhole: the more open the pinhole, the thicker the focal plane. When the pinhole is fully opened, the image resembles that obtained with a conventional light microscope.
Common Lasers and Parameters
Published in Mark Steven Csele, Laser Modeling, 2017
A typical ion laser consists of a ceramic tube filled with a noble gas (commonly argon or krypton) at low pressure and excited by a high-current discharge, which can range from 10A for the smallest argon-ion tubes to over 70A for a large-frame, water-cooled ion laser. A moderate-sized argon laser with a 5W visible output operates with a current of 40A and a tube voltage of 250V. This represents a total power dissipation of 10kW, so water cooling is required. The smallest ion laser tubes dissipate about 1kW and can be forced-air cooled by a large blower. The high current discharge and the high temperature of the plasma within the tube require the tube to be built in a rather unique way compared to many gas lasers. The tube itself, for instance, is manufactured of ceramic materials to withstand thermal shock during operation, and the discharge is confined to a center bore by tungsten disks within that ceramic tube. A heated cathode is required with such a high-current discharge to enhance the life of the cathode by lowering the power dissipated by this structure. In addition, a moderate to large ion laser tube requires a large magnetic field generated by an electromagnet coaxial to the tube (which also serves as a cooling water jacket) to confine the discharge further to the center of the tube, increasing current density.
Role of multi-layered graphene as an additional fuel on energy release of Al/MoO3 nano-thermite
Published in Philosophical Magazine, 2022
Priya Thakur, Vimal Sharma, Nagesh Thakur
The XRD (Panalytical 3050/60 X’Pert-PRO) patterns analyzed the composition of nano-thermites using CuKα (λ = 1.54060 Å) radiation source. Samples were scanned by diffraction angle (2θ) from 10° to 80°, scanning step interval (s), as well as step size, were 0.02 and 0.5, respectively. Elemental and morphological composition analysis of the synthesised was done using powdered samples uniformly spread on carbon tape for imaging by the FEI Quanta FEG 450 FESEM, which worked at 45 kV. ZAF correction method is applied to EDX measurements in the FESEM to convert apparent concentrations (X-ray peak intensity) into the composition of sample. Here, Z, A and F stand for atomic number effect, absorption effect and fluorescence effect, respectively. To study the microstructural properties, the powder sample was sonicated for 2 h immersed in cyclohexane. The drop of sonicated solvent was dried on a carbon grid at room temperature, which was subsequently used for HRTEM (JEOL JEM 2100F) analysis at 200 kV. In nano-thermite samples, the structural stability of used MLG nanoplatelets was examined by Raman spectra in the 1000–2000 cm−1 range using the Renishaw InVia Raman microscope. Ar-ion laser of wavelength 514 nm was used for this characterisation technique. The energy release, weight loss, and activation energy during thermite reaction were measured using TGA/DSC (EXSTAR TG/DTA 6300). In the DSC/TGA experiment samples, were heated upto1000°C at 5, 10, 15 and 20°C/min heating rates under nitrogen gas flow (200 mL/min).
Enhanced outer peaks in turbulent boundary layer using uniform blowing at moderate Reynolds number
Published in Journal of Turbulence, 2022
Gazi Hasanuzzaman, Sebastian Merbold, Vasyl Motuz, Christoph Egbers
Two channel, single point, noninvasive LDA technique in back scattering mode was used for the measurement. LDA setup consists of the followings: an Argon-ion continuous wave laser (Ion laser technology) was used as the laser source. At all cross sections along the laser beam, the intensity has a Gaussian distribution, and the width of the beam is usually defined by the edge-intensity being of the core-intensity. The transmitting optics includes beam splitter where a coherent light beam of wavelength λ is split equally. One beam passes through a 40-MHz bragg cell where frequency of one beam is decreased by the shift frequency . Different optical paths of shifted and unshifted beam are compensated through cylindrical lens by allowing the unshifted beam to pass through it. Finally, monochromatic lens installed within the transmitting optics focuses both the splitted beams at same focal length using a beam expander (expander ratio () = 1.98) so that they intersect with the angle θ. Simultaneously the aperture of optical receiver was adjusted to a greater value (95 mm) so that it receives more of the reflected light from the particles. Therefore, focal length of the front lens from transmitting optics () was obtained at % mm.
Tuning the properties of Fe-BTC metal-organic frameworks (MOFs) by swift heavy ion (SHI) irradiation
Published in Radiation Effects and Defects in Solids, 2021
Pasha W. Sayyad, Nikesh N. Ingle, Gajanan A. Bodkhe, Megha A. Deshmukh, Harshada K. Patil, Sumedh M. Shirsat, Fouran Singh, Mahendra D. Shirsat
Raman spectra of MOF materials were recorded using AIRIX corp (STR150 Raman, Japan). The measurements were carried out using an argon ion laser (λ = 532 nm). The Raman spectra of the pristine and the irradiated Fe-BTC materials gave further insights into the interactions between the ion beam and Fe-BTC MOF. The Raman peaks in pristine Fe-BTC at 1610 and 1006 cm−1 can be assigned to C = C stretching modes of the aromatic rings in the Fe-BTC linker molecules. The peaks at 826 cm−1 are ascribed to out-of-plane ring (C–H) bending vibrations (33). The band observed at 1460 cm−1 corresponds to the symmetric stretching of O–C-O, whereas the peak at 1545 cm−1 to the asymmetric stretching of O–C-O (22). In the low-frequencies region (170-600 cm-1 range), the Fe-BTC does not exhibit any peak for irradiated samples. The Raman peak at 1125 cm−1 was observed due to the high energy 197Au8+ ion beam irradiated on Fe-BTC thin film. The peaks for vibrational modes between 150 and 600 cm−1 involving Fe3+ ions are evident in pristine Fe-BTC, which is not observed in the irradiated sample. Hence it may be concluded that the coordination bond between metal ions to organic linker has been broken, and all structure collapsed, which is experimental evidence from Raman spectra for irradiated samples with fluence 1 × 1011 and 1 × 1012 ions/cm2 Figure 6.