scholarly journals Application of Emission and Absorption Spectroscopy for Characterization of a Copper Converting Process

1988 ◽  
Vol 42 (1) ◽  
pp. 128-133 ◽  
Author(s):  
Wilhelm Wendt ◽  
Marcus Aldén ◽  
Willy Persson

The emission and absorption spectra of a copper converter flame have been investigated. It was found that the emission spectra consisted of Planck radiation and superimposed discrete structures. The band structure was dominated by PbS in the slag-making stage and by PbO in the copper-making stage. Towards the end of the slag-making stage the ratio of the PbO and PbS band intensities (PbO/PbS) changed, in good agreement with thermodynamical calculations. Absorption measurements were performed during the copper-making stage, where the absorption edge of SO2 at about 380 nm was the dominating feature. The implications of these measurements for process steering and control are discussed.

1999 ◽  
Vol 14 (4) ◽  
pp. 1235-1237 ◽  
Author(s):  
Ernst Z. Kurmaev ◽  
Sergei N. Shamin ◽  
David L. Ederer ◽  
Ursula Dettlaff-Weglikowska ◽  
Jörg Weber

Silicon L2,3 x-ray emission spectra (XES) of siloxene powder samples prepared according to Wöohler and Kautsky (Wöhler and Kautsky siloxene) are presented. The results are compared with the Si L2,3 spectra of the reference compounds a-Si, c-Si, SiO2, and SiOx. A close similarity of the electronic structure of Wöhler siloxene to that of a-SiO0.43: H and of Kautsky siloxene to that of a-SiO0.87: H is found. We determine the number of oxygen atoms per Si atom at ~0.5 in Wöhler siloxene and ~0.8 in Kautsky siloxene. The relative concentrations are in good agreement with the results of infrared absorption measurements on the same samples.


2014 ◽  
Vol 2014 ◽  
pp. 1-9
Author(s):  
Maurício N. Pontuschka ◽  
Ijar M. da Fonseca

The main objective of this paper is the study of a FDIR for an IMU aiming at space applications with focus on the gyro signal analysis and the tests of the filtering algorithms. The algorithms have been tested by using lab data provided by the DMC LABSIM (Physical’s Simulation Laboratory of the Space Mechanics and Control Division of INPE). The results have demonstrated good agreement with the concepts applied in this study. Automatic detection procedures are very important in the characterization of occurrence, definition of criteria, and device types in the scenario of AOCS FDIR. An IMU comprised of four gyros in a tetrahedral configuration is one of the assumed components for the AOCS (attitude and orbit control subsystem) considered in this work. The types of failures considered in this paper are the step abrupt change, ramp/drift/slow, stuck, cyclic, erratic, spike, and finally the stuck for variance alteration noise. An appropriate algorithm for the automatic detection of each type of fault is developed. The approach includes the mapping capability of fault event indicators to the IMU. This mapping is very important in the characterization of the occurrence, definition of criteria, and device types as well as associated fault identification for an AOCS.


Open Physics ◽  
2009 ◽  
Vol 7 (2) ◽  
Author(s):  
Zhenbao Feng ◽  
Haiquan Hu ◽  
Shouxin Cui

AbstractA series of calculations from first principles have been carried out to study structural, electronic, and optical properties of ZnSxSe1−x alloys. Our results show that the lattice constant scales linearly with sulfur composition. The imaginary parts of the dielectric function are calculated, which are in good agreement with the experimental data. We have also interpreted the origin of the spectral peaks on the basis of band structure and density of states. Additionally, we find that no bowing effect in the absorption edge is observed, unlike other II-VI semiconductor alloys.


2002 ◽  
Vol 09 (02) ◽  
pp. 1097-1102
Author(s):  
E. Z. KURMAEV ◽  
I. I. LYAKHOVSKAYA ◽  
J. KORTUS ◽  
M. DEMETER ◽  
M. NEUMANN ◽  
...  

Measurements of X-ray emission and absorption of the constituents of MgB 2 are presented. The results obtained are in good agreement with calculated X-ray spectra, with dipole matrix elements taken into account. The comparison of X-ray emission spectra of graphite, AlB 2, and MgB 2 in the binding energy scale supports the idea of charge transfer from σ to π bands, which creates holes at the top of the bonding σ bands and drives the high-Tc superconductivity in MgB 2.


2000 ◽  
Vol 639 ◽  
Author(s):  
P. Perlin ◽  
T. Suski ◽  
P. Wisniewski ◽  
I. Gorczyca ◽  
S. Lepkowski ◽  
...  

ABSTRACTWe have studied an influence of pressure on the emission and absorption spectra measured from various types of InGaN structures such as epilayers, quantum wells and quantum dots. While the known pressure coefficients of GaN and InN bandgaps are in the range 40-25 meV/GPa, the experimental observation for the light emission shift with pressure for InGaN alloys is dramatically different. With the increasing In content and thus decreasing emission energy the observed pressure coefficients become very small eventually reaching zero or even slightly negative values! We have observed a much weaker trend for the decrease of the pressure coefficient for the absorption edges of InGaN. First principle calculations of InGaN band structure and its modification with a pressure are not able to explain the huge effect observed in the emission experiment but are in a good agreement with the results obtained in optical absorption measurements. We discuss here the possible mechanisms which can account for extremely low pressure coefficient of the light emission and the discrepancy between sensitivity light emission and absorption on applied pressure in InGaN alloys.


2021 ◽  
Vol 8 ◽  
Author(s):  
Toshiaki Nagai ◽  
Ashitaka Kurita ◽  
Jun Shintake

Biodegradability is an important property for soft robots that makes them environmentally friendly. Many biodegradable materials have natural origins, and creating robots using these materials ensures sustainability. Hence, researchers have fabricated biodegradable soft actuators of various materials. During microbial degradation, the mechanical properties of biodegradable materials change; these cause changes in the behaviors of the actuators depending on the progression of degradation, where the outputs do not always remain the same against identical inputs. Therefore, to achieve appropriate operation with biodegradable soft actuators and robots, it is necessary to reflect the changes in the material properties in their design and control. However, there is a lack of insight on how biodegradable actuators change their actuation characteristics and how to identify them. In this study, we build and validate a framework that clarifies changes in the mechanical properties of biodegradable materials; further, it allows prediction of the actuation characteristics of degraded soft actuators through simulations incorporating the properties of the materials as functions of the degradation rates. As a biodegradable material, we use a mixture of gelatin and glycerol, which is fabricated in the form of a pneumatic soft actuator. The experimental results show that the actuation performance of the physical actuator reduces with the progression of biodegradation. The experimental data and simulations are in good agreement (R2 value up to 0.997), thus illustrating the applicability of our framework for designing and controlling biodegradable soft actuators and robots.


2020 ◽  
Vol 1 (2) ◽  
pp. 5-8
Author(s):  
Komang Gde Suastika, Heri Suyanto, Gunarjo, Sadiana, Darmaji

Abstract - Laser-Induced Breakdown Spectroscopy (LIBS) is one method of atomic emission spectroscopy using laser ablation as an energy source. This method is used to characterize the type of amethysts that originally come from Sukamara, Central Kalimantan. The result of amethyst characterization can be used as a reference for claiming the natural wealth of the amethyst. The amethyst samples are directly taken from the amethyst mining field in the District Gem Amethyst and consist of four color variations: white, black, yellow, and purple. These samples were analyzed by LIBS, using laser energy of 120 mJ, delay time detection of 2 μs and accumulation of 3, with and without cleaning. The purpose of this study is to determine emission spectra characteristics, contained elements, and physical characteristics of each amethyst sample. The spectra show that the amethyst samples contain some elements such as Al, Ca, K, Fe, Gd, Ba, Si, Be, H, O, N, Cl and Pu with various emission intensities. The value of emission intensity corresponds to concentration of element in the sample. Hence, the characteristics of the amethysts are based on their concentration value. The element with the highest concentration in all samples is Si, which is related to the chemical formula of SiO2. The element with the lowest concentration in all samples is Ca that is found in black and yellow amethysts. The emission intensity of Fe element can distinguish between white, purple, and yellow amethyst. If Fe emission intensity is very low, it indicates yellow sample. Thus, we may conclude that LIBS is a method that can be used to characterize the amethyst samples.Key words: amethyst, impurity, laser-induced, breakdown spectroscopy, characteristic, gemstones


2006 ◽  
Vol 1 (2) ◽  
Author(s):  
P. Literathy ◽  
M. Quinn

Petroleum and its refined products are considered the most complex contaminants frequently impacting the environment in significant quantities. They have heterogeneous chemical composition and alterations occur during environmental weathering. No single analytical method exists to characterize the petroleum-related environmental contamination. For monitoring, the analytical approaches include gravimetric, spectrometric and chromatographic methods having significant differences in their selectivity, sensitivity and cost-effectiveness. Recording fluorescence fingerprints of the cyclohexane extracts of the water, suspended solids, sediment or soil samples and applying appropriate statistical evaluation (e.g. by correlating the concatenated emission spectra of the fingerprints of the samples with arbitrary standards (e.g. petroleum products)), provides a powerful, cost-effective analytical tool for characterization of the type of oil pollution and detecting the most harmful aromatic components of the petroleum contaminated matrix. For monitoring purposes, the level of the contamination can be expressed as the equivalent concentration of an appropriate characteristic standard, based on the fluorescence intensities at the relevant characteristic wavelengths. These procedures are demonstrated in the monitoring of petroleum-related pollution in the water and suspended sediment in the Danube river basin


Author(s):  
Elizabeth S. Radcliffe

The Introduction offers, first, a brief historical background to Hume’s theory of the passions, which is further elaborated in the APPENDIX. Foremost among the theses of the early modern rationalists—like Reynolds, Senault, Descartes, Cudworth, and Clarke—to which Hume is responding are: that many passions left unregulated lead to the pursuit of unsuitable objects, that reason can overcome the pernicious influence of the passions and control our actions, and that the passions are states that represent good and evil. Second, the Introduction presents a sketch of Hume’s characterization of reason and passion and his account of their relationship. Third, it explains the method of interpretation used in this book and previews its chapters. The approach is coherentist: to present an intelligible and consistent picture of Hume’s theory of passion and action, accounting for as many of the relevant texts as possible.


Robotica ◽  
2020 ◽  
pp. 1-18
Author(s):  
M. Garcia ◽  
P. Castillo ◽  
E. Campos ◽  
R. Lozano

SUMMARY A novel underwater vehicle configuration with an operating principle as the Sepiida animal is presented and developed in this paper. The mathematical equations describing the movements of the vehicle are obtained using the Newton–Euler approach. An analysis of the dynamic model is done for control purposes. A prototype and its embedded system are developed for validating analytically and experimentally the proposed mathematical representation. A real-time characterization of one mass is done to relate the pitch angle with the radio of displacement of the mass. In addition, first validation of the closed-loop system is done using a linear controller.


Sign in / Sign up

Export Citation Format

Share Document