Residual Magnetic Moment Influences the Features of Fe3s XPS Spectrum: A Case Study

2021 ◽  
Vol 15 ◽  
Author(s):  
Ranjan K Sahu
Keyword(s):  
Magnetic Moment ◽  
Magnetic Domain ◽  
Anomalous Behavior ◽  
Spectral Features ◽  
Different Temperatures ◽  
Magnetic Origin ◽  
Xps Study ◽  
Increasing Temperature ◽  
Curie Temperature Tc

Background: Fe 3sXPS spectrumexhibits doublet peak instead of predicted singlet peak based on spin-orbit coupling theory. This anomalous behavior is considered to be magnetic origin. However, the effect of residual magnetic moment to the features of Fe3s doublet peakis not understood fully. Objective: This study aims to verify the effect of residual magnetic moment on the spectral features of Fe3s XPS spectrum of magnetic material. Method: As a case study, we have carried out a high temperature XPS study of the Fe 3s spectrum of magnetic domain aligned (MDA) sample with composition composed of SrFe10.8Al1.2O19. In addition, the XPS data have been compared with the data acquired at different temperatures of magnetic domain non-aligned (MDNA) sample. Results: The results show that the majority peak intensity and minority peak width of Fe 3s spectrum of MDA are smaller than those of the MDNA sample, and they increase systematically with increasing temperature. However, it is noted that the features of Fe3s spectrum of both MDA and MDNA samples are completely overlapped near and above the Curie temperature, Tc ~ 670K. Conclusion: The analysis of XPS data suggests that the residual magnetic moment influences the spectral features of Fe3s spectrum. These results provide evidences that it is important to consider the contribution of residual magnetic moment while deriving information from Fe 3s XPS spectrum of MDA sample.

scholarly journals A Comparative Electrochemical and Morphological Investigation on the Behavior of NiCr and CoCr Dental Alloys at Various Temperatures

Metals ◽  
2021 ◽  
Vol 11 (2) ◽  
pp. 256
Author(s):  
Florentina Golgovici ◽  
Mariana Prodana ◽  
Florentina Gina Ionascu ◽  
Ioana Demetrescu
Keyword(s):  
Low Temperatures ◽  
Artificial Saliva ◽  
Electrochemical Stability ◽  
Morphological Investigation ◽  
Dental Alloys ◽  
Ion Release ◽  
Icp Ms ◽  
Different Temperatures ◽  
Good Concordance ◽  
Increasing Temperature

The purpose of our study is to compare the behavior of two reprocessed dental alloys (NiCr and CoCr) at different temperatures considering the idea that food and drinks in the oral cavity create various compositions at different pH levels; the novelty is the investigation of temperature effect on corrosion parameters and ion release of dental alloys. Electrochemical stability was studied together with morphology, elemental composition and ions release determination. The results obtained are in good concordance: electrochemistry studies reveal that the corrosion rate is increasing by increasing the temperature. From SEM coupled with EDS, the oxide film formed on the surface of the alloys is stable at low temperatures and a trend to break after 310K. ICP-MS results evidence that in accordance with increasing temperature, the quantities of ions released from the alloys immersed in artificial saliva also increase, though they still remain small, less than 20 ppm.

scholarly journals Simulation of FDSOI-ISFET with Tunable Sensitivity by Temperature and Dual-Gate Structure

Electronics ◽  
2021 ◽  
Vol 10 (13) ◽  
pp. 1585
Author(s):  
Hanbin Wang ◽  
Jinshun Bi ◽  
Mengxin Liu ◽  
Tingting Han
Keyword(s):  
Gate Voltage ◽  
Computer Aided Design ◽  
Silicon On Insulator ◽  
Fully Depleted ◽  
Gate Structure ◽  
Different Temperatures ◽  
Dual Gate ◽  
Sensitivity Changes ◽  
Increasing Temperature ◽  
Aided Design

This work investigates the different sensitivities of an ion-sensitive field-effect transistor (ISFET) based on fully depleted silicon-on-insulator (FDSOI). Using computer-aided design (TCAD) tools, the sensitivity of a single-gate FDSOI based ISFET (FDSOI-ISFET) at different temperatures and the effects of the planar dual-gate structure on the sensitivity are determined. It is found that the sensitivity increases linearly with increasing temperature, reaching 890 mV/pH at 75 °C. By using a dual-gate structure and adjusting the control gate voltage, the sensitivity can be reduced from 750 mV/pH at 0 V control gate voltage to 540 mV/pH at 1 V control gate voltage. The above sensitivity changes are produced because the Nernst limit changes with temperature or the electric field generated by different control gate voltages causes changes in the carrier movement. It is proved that a single FDSOI-ISFET can have adjustable sensitivity by adjusting the operating temperature or the control gate voltage of the dual-gate device.

scholarly journals Insect body size changes under future warming projections: a case study of Chironomidae (Insecta: Diptera)

Hydrobiologia ◽  
2021 ◽  
Author(s):  
Rungtip Wonglersak ◽  
Phillip B. Fenberg ◽  
Peter G. Langdon ◽  
Stephen J. Brooks ◽  
Benjamin W. Price
Keyword(s):  
Body Size ◽  
Ambient Temperature ◽  
Wing Length ◽  
The Body ◽  
Mesocosm Experiments ◽  
Future Warming ◽  
Increasing Temperature ◽  
Emergence Date ◽  
Average Body

AbstractChironomids are a useful group for investigating body size responses to warming due to their high local abundance and sensitivity to environmental change. We collected specimens of six species of chironomids every 2 weeks over a 2-year period (2017–2018) from mesocosm experiments using five ponds at ambient temperature and five ponds at 4°C higher than ambient temperature. We investigated (1) wing length responses to temperature within species and between sexes using a regression analysis, (2) interspecific body size responses to test whether the body size of species influences sensitivity to warming, and (3) the correlation between emergence date and wing length. We found a significantly shorter wing length with increasing temperature in both sexes of Procladius crassinervis and Tanytarsus nemorosus, in males of Polypedilum sordens, but no significant relationship in the other three species studied. The average body size of a species affects the magnitude of the temperature-size responses in both sexes, with larger species shrinking disproportionately more with increasing temperature. There was a significant decline in wing length with emergence date across most species studied (excluding Polypedilum nubeculosum and P. sordens), indicating that individuals emerging later in the season tend to be smaller.

scholarly journals Correlation and prediction of solubility of hydrogen in alkenes and its dissolution properties

2021 ◽  
Author(s):  
Mohammad Jamali ◽  
Amir Abbas Izadpanah ◽  
Masoud Mofarahi
Keyword(s):  
Equation Of State ◽  
Binary Interaction ◽  
Absolute Deviation ◽  
Dissolution Properties ◽  
Different Temperatures ◽  
Binary Interaction Parameters ◽  
Delta G ◽  
Hoff Equation ◽  
Increasing Temperature ◽  
Total Average

AbstractIn this work, solubility of hydrogen in some alkenes was investigated at different temperatures and pressures. Solubility values were calculated using the Peng–Robinson equation of state. Binary interaction parameters were calculated using fitting the equation of state on experimental data, Group contribution method and Moysan correlations and total average absolute deviation for these methods was 3.90, 17.60 and 13.62, respectively. Because hydrogen solubility in Alkenes is low, Henry’s law for these solutions were investigated, too. Results of calculation showed with increasing temperature, Henry’s constant was decreased. The temperature dependency of Henry’s constants of hydrogen in ethylene and propylene was higher than to other alkenes. In addition, using Van’t Hoff equation, the thermodynamic parameters for dissolution of hydrogen in various alkenes were calculated. Results indicated that the dissolution of hydrogen was spontaneous and endothermic. The total average of dissolution enthalpy ($${\Delta H}^{^\circ }$$ Δ H ∘ ) and Gibbs free energy ($${\Delta G}^{^\circ }$$ Δ G ∘ ) for these systems was 3.867 kJ/mol and 6.361 kJ/mol, respectively. But dissolution of hydrogen in almost of alkenes was not an entropy-driven process.

Temperature Dependence of Hole Impact Ionization Coefficient in 4H-SiC Photodiodes

2009 ◽  
Vol 615-617 ◽  
pp. 311-314 ◽  
Author(s):  
W.S. Loh ◽  
J.P.R. David ◽  
B.K. Ng ◽  
Stanislav I. Soloviev ◽  
Peter M. Sandvik ◽  
...  
Keyword(s):  
Phonon Scattering ◽  
Impact Ionization ◽  
Positive Temperature Coefficient ◽  
Positive Temperature ◽  
Different Temperatures ◽  
Ionization Coefficients ◽  
Increasing Temperature ◽  
The Impact ◽  
Good Agreement ◽  
Ionization Rates

Hole initiated multiplication characteristics of 4H-SiC Separate Absorption and Multiplication Avalanche Photodiodes (SAM-APDs) with a n- multiplication layer of 2.7 µm were obtained using 325nm excitation at temperatures ranging from 300 to 450K. The breakdown voltages increased by 200mV/K over the investigated temperature range, which indicates a positive temperature coefficient. Local ionization coefficients, including the extracted temperature dependencies, were derived in the form of the Chynoweth expression and were used to predict the hole multiplication characteristics at different temperatures. Good agreement was obtained between the measured and the modeled multiplication using these ionization coefficients. The impact ionization coefficients decreased with increasing temperature, corresponding to an increase in breakdown voltage. This result agrees well with the multiplication characteristics and can be attributed to phonon scattering enhanced carrier cooling which has suppressed the ionization process at high temperatures. Hence, a much higher electric field is required to achieve the same ionization rates.

scholarly journals Experimental Investigation of Wave Velocity-Permeability Model for Granite Subjected to Different Temperature Processing

Geofluids ◽  
2017 ◽  
Vol 2017 ◽  
pp. 1-10 ◽  
Author(s):  
Guanghui Jiang ◽  
Jianping Zuo ◽  
Teng Ma ◽  
Xu Wei
Keyword(s):  
Particle Size ◽  
High Temperature ◽  
Wave Velocity ◽  
Pore Fluid ◽  
Rock Matrix ◽  
Permeability Model ◽  
Wave Velocities ◽  
Before And After ◽  
Different Temperatures ◽  
Increasing Temperature

Understanding the change of permeability of rocks before and after heating is of great significance for exploitation of hydrocarbon resources and disposal of nuclear waste. The rock permeability under high temperature cannot be measured with most of the existing methods. In this paper, quality, wave velocity, and permeability of granite specimen from Maluanshan tunnel are measured after high temperature processing. Quality and wave velocity of granite decrease and permeability of granite increases with increasing temperature. Using porosity as the medium, a new wave velocity-permeability model is established with modified wave velocity-porosity formula and Kozeny-Carman formula. Under some given wave velocities and corresponding permeabilities through experiment, the permeabilities at different temperatures and wave velocities can be obtained. By comparing the experimental and the theoretical results, the proposed formulas are verified. In addition, a sensitivity analysis is performed to examine the effect of particle size, wave velocities in rock matrix, and pore fluid on permeability: permeability increases with increasing particle size, wave velocities in rock matrix, and pore fluid; the higher the rock wave velocity, the lower the effect of wave velocities in rock matrix and pore fluid on permeability.

Tensile Properties of Low Nickel Austenitic Stainless Steel at Elevated Temperatures

2012 ◽  
Vol 159 ◽  
pp. 346-350
Author(s):  
Shu Min Liu ◽  
Jian Bin Zhang
Keyword(s):  
Tensile Strength ◽  
Stainless Steel ◽  
Elevated Temperatures ◽  
Peak Stress ◽  
Temperature Curve ◽  
Delta Ferrite ◽  
Cross Sectional ◽  
Different Temperatures ◽  
Increasing Temperature ◽  
Reduction Percentage

The elevated temperature short-time tensile test with the sample of casting low nickel stainless steel was conducted on SHIMADZU AG-10 at ten temperatures 300, 500, 600, 700, 800, 950, 1000, 1050, 1100, and 1250°C, respectively. The stress-strain curves with the thermal deformation at the different temperatures, the peak stress intensity-temperature curve, and the reduction percentage of cross sectional area-temperature curve were obtained. Metallographic test samples were prepared and the morphology of deforming zone was observed by optical microscopy. The experimental results show that the tensile strength of the test samples decreases with increasing temperature. From 300 to 800°C, the work harding occurred and the tensile strength increases with increasing strain. The work softening occurred and the tensile strength decreases with increasing strain at temperatures of 800 to 1250°C. The minimum value of reduction percentage was measured at 800 °C. The austenite and delta-ferrite are the main phase in the tested samples. When the tensile temperatures are increased to 1200°C, the delta-ferrite became thinner and broke down to be spheroidized.

Effect on Vulcanized Rubber Compounds of Immersion in Boiling Water

1931 ◽  
Vol 4 (3) ◽  
pp. 426-436
Author(s):  
K. J. Soule
Keyword(s):  
Water Absorption ◽  
Room Temperature ◽  
Anomalous Behavior ◽  
Boiling Water ◽  
Vulcanized Rubber ◽  
Rubber Compounds ◽  
Different Temperatures ◽  
Actual Change

Abstract Further work is very desirable on the effect of different accelerators, antioxidants, and fluxes. It is possible that their study will throw more light on the mechanism of the swelling phenomena, and also help to explain the anomalous behavior of some of the fillers tested. It would also seem to be worth while to study the action of a few selected stocks in water, at several temperatures between room temperature and 100° C., to determine if the water absorption and swelling merely increase with rising temperatures, or whether there might be an actual change in behavior at different temperatures.

Electronic Transport Properties of Hot-Pressed B6Si

1987 ◽  
Vol 97 ◽  
Author(s):  
C. Wood ◽  
D. Emin ◽  
R. S. Feigelson ◽  
I. D. R. Mackinnon
Keyword(s):  
Electrical Conductivity ◽  
Seebeck Coefficient ◽  
Transport Properties ◽  
Electronic Transport ◽  
Hall Mobility ◽  
Anomalous Behavior ◽  
Nominal Composition ◽  
Electronic Transport Properties ◽  
Increasing Temperature ◽  
P Type

ABSTRACTMeasurements of the electrical conductivity, Seebeck coefficient and Hall mobility from -300 K to -1300 K have been carried out on multiphase hotpressed samples of the nominal composition B6Si. In all samples the conductivity and the p-type Seebeck coefficient both increase smoothly with increasing temperature. By themselves, these facts suggest small-polaronic hopping between inequivalent sites. The measured Hall mobilities are always low, but vary in sign. A possible explanation is offered for this anomalous behavior.

Study the Effect of Heat Treatment and Pressure on some the Optical Properties of the Pure PVA Nano Polymer

2021 ◽  
Vol 900 ◽  
pp. 16-25
Author(s):  
Tabarak Mohammed Awad ◽  
May A.S. Mohammed
Keyword(s):  
Heat Treatment ◽  
Dielectric Constant ◽  
Refractive Index ◽  
Optical Properties ◽  
Absorption Coefficient ◽  
Polyvinyl Alcohol ◽  
Complex Dielectric Constant ◽  
Different Temperatures ◽  
German Origin ◽  
Increasing Temperature

In this study, some optical properties were studied of the pure vinyl polyvinyl alcohol (PVA) nanopolymer (German origin). Under the influence of different temperatures and pressures of PVA. Where 25 samples were prepared for the purpose of conducting the research. Which studied the study of these samples was done by recording the absorbance and transmittance spectra of the wavelengths (200-900) nm. From them, absorbance, transmittance, reflectivity, absorption coefficient, refractive index, extinction coefficient, complex dielectric constant were calculated. At different temperatures (25,40, 80, 120, 160)°C. And with different pressures within the range (7.5,8,8.5,9,9.5) MPa. The results are that the permeability of the polymer (PVA) at different temperatures for each pressure decreases with increasing temperature, and that all other calculated optical properties increase with increasing temperature.

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