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Lighting Systems
Published in Dale R. Patrick, Stephen W. Fardo, Brian W. Fardo, Electrical Power Systems Technology, 2021
Dale R. Patrick, Stephen W. Fardo, Brian W. Fardo
The human eye responds to electromagnetic waves in the visible light band of frequencies. Each color of light has a different frequency or wavelength. In order of increasing frequency (or decreasing wavelengths), the colors are red, orange, yellow, green, blue, indigo, and violet. The wavelengths of visible light are in the 400-millimicrometer (violet) to 700-mil-limicrometer (red) range. A micrometer (mm), which is also called a micron (μm), is one-millionth of a meter, and a nanometer (nm) is 1 × 10–3 micrometer. Angstrom units (Å) are also used for light measurement. An angstrom unit is one-tenth of a nanometer. In order to avoid confusion, use the conversion chart given in Table 13-1.
Lighting Systems
Published in Stephen W. Fardo, Dale R. Patrick, Electrical Power Systems Technology, 2020
Stephen W. Fardo, Dale R. Patrick
The human eye responds to electromagnetic waves in the visible light band of frequencies. Each color of light has a different frequency, or wavelength. In order of increasing frequency (or decreasing wavelengths), the colors are red, orange, yellow, green, blue, indigo, and violet. The wavelengths of visible light are in the 400-millimicrometer (violet) to 700-millimicrometer (red) range. A micrometer (mm), which is also called a micron (μm), is one millionth of a meter, and a nanometer (nm) is 1 × 10−3 micrometer. Angstrom units (Å) are also used for light measurement. An angstrom unit is one-tenth of a nanometer. In order to avoid confusion, use the conversion chart given in Table 13-1.
Model-Based Iterative Reconstruction for Electron Tomography
Published in Jeffrey P. Simmons, Lawrence F. Drummy, Charles A. Bouman, Marc De Graef, Statistical Methods for Materials Science, 2019
S.V. Venkatakrishnan, Lawrence F. Drummy
Driven by rapid advances in nanoscience, the past decade has witnessed an unprecedented interest in the development of new materials to solve key problems in areas ranging from energy to medicine. A key component in the development of advanced materials is to have the ability to quantitatively characterize samples at the nanometer and angstrom scale. Transmission electron microscopy (TEM) is a popular imaging method used in the physical and biological sciences for characterizing samples at the nanometer scale in 2D. The TEM has also been modified to characterize samples in 3D using the principles of tomography. Typically, tomography is carried out by using a sample holder that can tilt the sample about an axis and obtaining a sequence of images formed by measuring the scattered electrons which can then be inverted (see Figure 6.1). Because of sample motion during tilting, the images are aligned prior to the tomographic inversion. Due to mechanical limitations, it is usually not possible to obtain a full set of tilts, leading to a limited view dataset. Furthermore, in several applications, in order to limit beam damage to the sample (low-dose imaging) or acquire the data rapidly, the measurements need to be made rapidly, resulting in a dataset that is extremely noisy. Additionally, the measurements can be complex to model (and hence invert) due to dynamical diffraction effects such as Bragg scatter from crystalline materials. As a result, tomographic inversion of electron microscope data can be challenging. For a detailed review of electron tomography, the reader can refer to [680, 330, 309].
Preparation of mixed spinel catalyst support (CaxMg1-xAl2O4) reinforced by calcium oxide toward in the biodiesel production from vegetable oil
Published in International Journal of Green Energy, 2023
Hamed Nayebzadeh, Hossein Ajamein, Tahereh Zakizadeh, Behgam Rahmanivahid
The functional groups of supports were detected by the Fourier transform infrared spectroscopy through Spectrum Two analyzer (USA, Perkin Elmer, 400–4000 cm−1). An STA503 instrument (Germany, BAHR, 30°C to 800°C with a 10°C/min increasing rate and by an argon flow of 70 cm3/min) was used to study the thermogravimetric and differential thermal properties of synthesized supports. An X’Pert Pro diffractometer (Holland, Panalytical, Cu Kα: 1.54 angstrom, range 10–80°) was applied to investigate the crystallography properties of fabricated nanocatalysts. The morphology of synthesized nanocatalysts was probed by a MIRA3 FESEM device (Czech Republic, TESCAN). In addition, the particle size analysis was performed on FESEM images by the ImageJ software. The elemental composition of synthesized nanocatalysts and primary gel were analyzed using a VEGA II Detector (Czech Republic, TESCAN) through Energy dispersive X-ray (EDX) technique. BET-BJH analysis was used by a Belsorp mini II analyzer (Japan, Microtrac Bel Corp.) to calculate the specific surface areas of nanocatalysts. The density of basic sites on the nanocatalysts was measured by TPD-CO2 using a Micrometrics 2910 device.
A new mixed-ligand Co(II) coordination polymer: treatment activity on ulcerative colitis by inhibiting the JAK2/STAT3 signaling pathway in the colonic epithelial cells
Published in Inorganic and Nano-Metal Chemistry, 2021
Yan Tan, Hong-Yu Yun, Jing Tang, Du-Xiong Cai, Xiao-Ning Sun
JAKs (Janus kinases) contain tandem C-terminal pseudokinase (JH2) and tyrosine kinase (JH1) domains. Here we choose JAK2 (5UT1) as the probe protein for the investigation of the biological activity of the complex. The molecular docking results suggest that the interactions between the complex and the protein are originated from both the carboxylate oxygen and nitrogen atom of six-membered ring. As depicted in Figure 5, where the docking configurations with relative lower binding energies are displayed. In Figure 5a, we can see that two binding interactions are formed, one is between the nitrogen atom and residue ASP-569 (2.5 angstrom), the other is between the oxygen atom and residue HIS-538 (2.0 angstrom), the binding energy is –8.58 kcal/mol. In Figure 5b, the binding interactions are formed between oxygen atoms to residues LYS-607 (2.1 Å) and SER-602 (2.5 Å), the nitrogen atoms are not involved in this binding configuration, the binding energy is –7.89 kcal/mol. Similar to the second configuration, in Figure 5c, it is also seen that only the oxygen atoms are participating into the binding interactions, the binding distances are 1.7 Å to residue PHE-537 and 2.0 Å to residue SER-605, the binding energy is about −7.88 kcal/mol. In Figure 5d, the oxygen atom from the carboxy group has formed two interactions to residues LYS-539 (2.8 Å) and PHE-537 (1.8 Å), the binding energy is –7.61 kcal/mol. Together with the experiment results, the molecular docking results shed light on the understanding of the interacting forms between the complex and the protein.
Evaluation of the radiological hazard in electron beam welding
Published in Radiation Effects and Defects in Solids, 2021
S. Angelini, G. Cucchi, D. Mostacci
X-ray production by electrons interacting with matter has been investigated widely since the 30’s of the twentieth century, and is well described by now. In particular, Pella et al. (9,10) have developed a procedure to calculate bremsstrahlung emission due to the impact of electrons of energy E onto a material of atomic number Z. The following formula yields the number of photons per unit wavelength, per impinging electron and per steradian: where Z is the atomic number of the scattering material, λ the wavelength of a photon of energy E and the wavelength corresponding to the energy of the impinging electron. The relation between wavelength in angstrom and energy in keV is where the speed of light and the Planck constant .