Spectrographic Study Research Articles

On the green isolated proton auroras during Canada thanksgiving geomagnetic storm

The existence of detached/isolated auroral structures in the subauroral ionosphere has been recognized and studied for decades. One major subset of such detached auroras is the so-called “isolated proton aurora” (IPA). IPA is characterized by substantial hydrogen emissions and thus inferred to be proton aurora, but is also accompanied by other emission lines. In particular, IPA is usually dominated by 557.7 nm green-line emissions in optical luminosity. To date, there is still a lack of dedicated spectrographic study and detailed comparison among structures in different emission lines of IPA. The intensity ratios between the 557.7 nm and hydrogen emissions in IPA have not been well established from concurrent observations or theoretical models. In this study, we report an IPA event during ∼0245–0345 UT on 12 October 2021, the Canada Thanksgiving storm night. Using multi-station, multi-wavelength optical instruments, including the Transition Region Explorer (TREx) spectrograph, we investigate the evolution and spectrographic properties of the IPA. In-situ and ground magnetometer data show evidence of electromagnetic ion cyclotron (EMIC) waves associated with the passage of IPA, supporting a causal link between the EMIC wave and the proton precipitation. The precipitating proton energies are estimated to range between a few keV and a few tens of keV according to the IPA emission heights inferred from triangulation analyses. Via careful examination of the spectral intensities and the elevation-angle profiles of the 557.7, 427.8, and 486.1 nm emissions based on the spectrograph data, we conclude that the 557.7 nm emissions contained in the IPA were unlikely to owe their source to energetic electron precipitation from the magnetosphere, but were the byproduct of the proton precipitation. The intensity ratio between the 557.7 nm (427.8 nm) and the 486.1 nm emissions of the IPA are confined within a relatively narrow range around ∼26 (∼4), which may serve as validation tests for existing and developing proton transport models.

The KMOS galaxy evolution survey (KGES): the angular momentum of star-forming galaxies over the last ≈10 Gyr

ABSTRACT We present the KMOS Galaxy Evolution Survey (KGES), a K-band Multi-Object Spectrograph (KMOS) study of the H α and [N ii] emission from 288 K-band-selected galaxies at 1.2 ≲ z ≲ 1.8, with stellar masses in the range $\log _{10}(M_{*}/\rm {M}_{\odot })\approx 9$ – 11.5. In this paper, we describe the survey design, present the sample, and discuss the key properties of the KGES galaxies. We combine KGES with appropriately matched samples at lower redshifts from the KMOS Redshift One Spectroscopic Survey (KROSS) and the SAMI Galaxy Survey. Accounting for the effects of sample selection, data quality, and analysis techniques between surveys, we examine the kinematic characteristics and angular momentum content of star-forming galaxies at z ≈ 1.5, ≈1, and ≈0. We find that stellar mass, rather than redshift, most strongly correlates with the disc fraction amongst star-forming galaxies at z ≲ 1.5, observing only a modest increase in the prevalence of discs between z ≈ 1.5 and z ≈ 0.04 at fixed stellar mass. Furthermore, typical star-forming galaxies follow the same median relation between specific angular momentum and stellar mass, regardless of their redshift, with the normalization of the relation depending more strongly on how disc-like a galaxy’s kinematics are. This suggests that massive star-forming discs form in a very similar manner across the ≈10 Gyr encompassed by our study and that the inferred link between the angular momentum of galaxies and their haloes does not change significantly across the stellar mass and redshift ranges probed in this work.

Synthesis and implementation of polycrystalline ferrite material for smart sensor module

Keeping pace with facets of nanotechnology and its applications in the field of development of smart sensor module polycrystalline ferrite material plays significant role in development of sensing material. Hence, MgZn and NiZn polycrystalline ferrite have been synthesized by co-precipitation method. The formation of the materials is confirmed by characterization by X-ray powder diffraction, FTIR absorption. From the results of X-ray diffraction investigation, formation of single phase compositions is confirmed. The resulted structure is FCC with 311 as a prominent reflection. The average particle size obtains by using Scherrer relation and the range from 40 nm to 48 nm. The existence of the nanoparticles results into increase of the surface area required to favour adsorption mechanism. FTIR spectrographic studies, reveals the existence of various modes of the lattice vibration. These materials were used for development of the sensor for monitoring of Alcohol gas and temperature. The detection of alcohol and temperature is essential in various industries and for environmental prediction as well. The sensing elements of the sensors are developed using thick film technology and alcohol and temperature sensitive electrical properties are investigated. An operating temperature was optimized to 135 0C for gas sensing application. Deploying glass and ceramic substrate the sensor is developed. Electrical resistance of the sensor (Rg) is measured for alcohol gas and environment temperature and it shows decreasing trend with increase in the sensing parameters. Deploying this material smart electronic system is design using advance microcontroller. From, the results of this investigation, it can be concluded that, the compositions under investigation can be suitably used for deployment of Smart Sensor for sensing of alcohol and temperature.

Spectroscopic methods for determining of zonal soils erosion (Chuvash Republic, Russia)

Results of spectrographic study of zonal soils with different erosion degree on the territory of the Chuvash Republic are given. In the points of spectrographic research, the soil specimens were taken and agrochemically tested. Changes in received spectrograms were analyzed in soils subtypes context with subsequent comparison with agrochemical indicators. The obtained data will help to develop new rapid methods for determining soil fertility parameters for agricultural lands based on spectroscopic physical principles.

Functional Demarcation of Traditional Off-White Colored Water Pots Manufactured from Rajasthan Clayey Soils and Red Colored Water Pots from Gujarat Clayey Soils Using Spectrographic, Cooling and Strength Studies--A Case Study from Jodhpur, Rajasthan, India

ABSTRACTOff-white water pots have had sustained traditional acceptance for a long period of time in Jodhpur compared to red colored water pots imported from the neighboring Gujarat state. Both types of pots hold 20 liters of potable water. The fluorescence spectroscopy reveals dominance of silica, alumina and iron oxide in red pots from Gujarat whereas off-white pots from Rajasthan also have a slight excess of CaO and MgO. Fourier transform infrared spectroscopy reveals a firing temperature of 800 °C for off-white pots, which is comparatively less than that for red pots. A lower amount of Fe2O3 and higher MgO in off-white compared to red water pots is responsible for the color differentiation. Off-white pots show a better degree of cooling compared to red pots. Better resistance to load was observed in off-white pots compared to red pots. This study may imply influence of hidden techno-functional aspects towards sustainability of off-white pots in Jodhpur, Rajasthan.

COOL TRANSITION REGION LOOPS OBSERVED BY THEINTERFACE REGION IMAGING SPECTROGRAPH

We report on the first Interface Region Imaging Spectrograph (IRIS) study of cool transition region loops. This class of loops has received little attention in the literature. A cluster of such loops was observed on the solar disk in active region NOAA11934, in the Si IV 1402.8 \AA\ spectral raster and 1400 \AA\ slit-jaw (SJ) images. We divide the loops into three groups and study their dynamics and interaction. The first group comprises relatively stable loops, with 382--626\,km cross-sections. Observed Doppler velocities are suggestive of siphon flows, gradually changing from -10 km/s at one end to 20 km/s at the other end of the loops. Nonthermal velocities from 15 to 25 km/s were determined. These physical properties suggest that these loops are impulsively heated by magnetic reconnection occurring at the blue-shifted footpoints where magnetic cancellation with a rate of $10^{15}$ Mx/s is found. The released magnetic energy is redistributed by the siphon flows. The second group corresponds to two footpoints rooted in mixed-magnetic-polarity regions, where magnetic cancellation occurred at a rate of $10^{15}$ Mx/s and line profiles with enhanced wings of up to 200 km/s were observed. These are suggestive of explosive-like events. The Doppler velocities combined with the SJ images suggest possible anti-parallel flows in finer loop strands. In the third group, interaction between two cool loop systems is observed. Evidence for magnetic reconnection between the two loop systems is reflected in the line profiles of explosive events, and a magnetic cancellation rate of $3\times10^{15}$ Mx/s observed in the corresponding area. The IRIS observations have thus opened a new window of opportunity for in-depth investigations of cool transition region loops. Further numerical experiments are crucial for understanding their physics and their role in the coronal heating processes.

Estimation of Verdet Constant for KCl, KBr, MgCl<sub>2</sub> Using Faraday Rotator

Nowadays, the rapid development of optics technology, especially for laser technology and scientific fields is important. One of this optics theory is Faraday rotation. Way of light propagation in a material medium can be influenced by an external field. The applied magnetic field causes rotation of the plane of polarized light. This effect is due to the optical activity, a property of the material that causes the rotation of the electric field of an incident linear wave. In this paper, we present an experiment to measure the Verdet constant through Faraday Effect using the Faraday rotator. Verdet constant is a factor for relation of magnetic field and the length of the path. When this effect is used in spectrographic studies, we can find information on the properties of higher energy states. Used materials for this experiment are KCl, KBr, and MgCl2. We used three lasers with different wavelengths 405nm, 450nm, and 515nm. We shows that the linear polarized light rotates after passing the applied magnetic field, when it's parallel with the magnetic field vector. Verdet constant are calculated about 382, 429.125, and 311.625 in 450nm for KCl, KBr, MgCl2 solutions.

Estimation of Verdet Constant for KCl, KBr, MgCl<sub>2</sub> Using Faraday Rotator

Nowadays, the rapid development of optics technology, especially for laser technology and scientific fields is important. One of this optics theory is Faraday rotation. Way of light propagation in a material medium can be influenced by an external field. The applied magnetic field causes rotation of the plane of polarized light. This effect is due to the optical activity, a property of the material that causes the rotation of the electric field of an incident linear wave. In this paper, we present an experiment to measure the Verdet constant through Faraday Effect using the Faraday rotator. Verdet constant is a factor for relation of magnetic field and the length of the path. When this effect is used in spectrographic studies, we can find information on the properties of higher energy states. Used materials for this experiment are KCl, KBr, and MgCl2. We used three lasers with different wavelengths 405nm, 450nm, and 515nm. We shows that the linear polarized light rotates after passing the applied magnetic field, when it's parallel with the magnetic field vector. Verdet constant are calculated about 382, 429.125, and 311.625 in 450nm for KCl, KBr, MgCl2 solutions.

Putting a New Spin on Galaxies: Horace W. Babcock, the Andromeda Nebula, and the Dark Matter Revolution

1. IntroductionWhen a scientist is the first to perform a difficult type of observation and correctly interprets the result as a significant challenge to then-widely accepted core theories, and the result is later recognized as seminal work in a field of major importance, it is a surprise to find that that work was essentially ignored by the scientific community for thirty years. Such was the fate of the doctoral research on the rotations of the Andromeda Nebula (M31) conducted by Horace Welcome Babcock (1912-2003), who went on to become a very prominent astronomer - in an entirely different sub-field, never working on the subject of his dissertation again. This paper seeks to explain the 'non-reception' of Babcock's work on galactic dynamics and the reasons he did no further work in that sub-field. In particular this paper shows that, contrary to the claims of some commentators, the non-reception of Babcock's work should not be understood as an example of the unjust treatment of a young scientist by the conservative establishment.In 1939, Horace Babcock published the first detailed spectrographic study of M31.1 Babcock's spectra of M31, originally obtained for his doctoral dissertation at the Lick Observatory in California,2 showed a quite unexpected pattem. This unexpected pattem turned out to have massive implications for our understanding of the formation and composition of galaxies. Today Babcock's result is interpreted as an instance of what may be called the 'dynamical discrepancy in astrophysics', popularly known as 'the dark matter problem'. It indicates the need for a thorough overhaul of some of the most fundamental theories and assumptions in contemporary physics and astronomy. In his own time, however, Babcock's result caused barely a ripple within the astronomical community. In fact, despite the consilience provided by several related results obtained by others in the 1930s, it was not until the 1970s that the astronomical community gave the dynamical discrepancy the attention that it deserved, as we realise with the benefit of hindsight. This delay is something of a mystery, not least because the evidence itself did not change significantly in type or quality in the intervening period. As a corollary to explaining the non-reception of Babcock's work on M31, this paper also gives an analysis of some of the historical, sociological and institutional factors responsible for the slow response of the astronomical community to the early evidence for the existence and importance of the dynamical discrepancy.2. The Conceptual Background to the Dark Matter ProblemThe dynamical discrepancy is a significant and surprising disagreement between two different but seemingly independenuy rehable ways of estimating the masses of largescale astrophysical systems such as galaxies and clusters of galaxies. The internal motions within such systems are inconsistent with the known laws of physics given the distribution of direcdy detectable matter in those systems - that is, given just the matter directly observable in these systems and the known laws of physics, the rotation rates observed in them cannot be explained. The dynamical discrepancy was first discovered in the 1930s; despite concerted efforts (especially since the 1980s) it remains unresolved today. According to our current view, there are two classes of possible solutions: either (1) there is a great deal more mass in large-scale astrophysical systems than can be detected by any direct means; or (2) our best theory of gravity, Einstein's General Theory of Relativity, does not apply to those systems and therefore needs to be replaced. On the first option, the excess mass is 'dark' in the sense that it neither emits nor absorbs electromagnetic radiation at any wavelength. This is one of the reasons for thinking that the excess mass is likely not any form of matter with which we are already familiar (protons, neutrons, etc.). On the second option, some new theory will be needed to replace General Relativity as the theory describing gravitational interactions taking place over distances equal to or greater than the radius of a galaxy. …

Biologically Active Compounds from Lemna Minor S. F. Gray

The chemical composition of biologically active compounds of the common duckweed (Lemna minor) was studied. A titrimetric method was used to assay the total iodine content, a spectrophotometric method was used for flavonoids, expressed as luteolin-7-glucoside; gas chromatography/mass spectrometry was used to identify 32 lipophilic substances of various chemical groups. Atomic emission spectrographic studies identified 14 macro and trace elements in the common duckweed. Studies of biologically active substances in the common duckweed are of interest for further investigation of its pharmacological properties with the aim of seeking new medicinal agents.

Mineral Trapping and Sequestration of Carbon-dioxide in Deccan Basalts: SEM, FTIR and Raman Spectroscopic Studies on Secondary Carbonates

Abstract Increasing CO2 emissions and global warming are posing problems for carbon management. Results of laboratory experiments, probing the carbon sequestration potential of picrites from Igatpuri Formation, Deccan Flood Basalt Volcanic Province, India are reported here. The picrites which were reacted with water and carbon dioxide in its supercritical condition for about 5 months duration at 100°C temperature and 60 bars of CO2 pressure clearly show the growth of secondary carbonates over the surface as well as in the intergranular spaces. SEM-EDS studies, Infrared spectroscopic analysis and Raman spectrographic studies also confirm the development of secondary carbonates in the reacted picrite samples.

Microcalorimetric and spectrographic studies on host–guest interactions of α-, β-, γ- and Mβ-cyclodextrin with resveratrol

Thermal effects of inclusion processes of α-, β-, γ- and Mβ-cyclodextrin with resveratrol (RES) in aqueous solutions were determined by isothermal titration calorimetry (ITC) with nanowatt sensitivity at the temperature of 298.15 K. Standard enthalpy changes, stoichiometry and equilibrium constants of the inclusion complexes were derived from the direct calorimetric data utilizing nonlinear simulation. The thermodynamic parameters were discussed in the light of weak interactions between the host and the guest molecules combining with UV spectral message. The results indicate that all of the complexes formed in the aqueous solutions are in 1:1 stoichiometry. The binding processes of α-, β- and Mβ-cyclodextrin with the guest are mainly driven by enthalpy, while that of γ-cyclodextrin with the drug is driven by both enthalpy and entropy.

Microcalorimetric and spectrographic studies on the interaction of DNA with betaxolol

The interaction of calf thymus deoxyribonucleic acid (ct-DNA) with betaxolol (BET) in aqueous buffer solution (pH 7.40) has been investigated using isothermal titration calorimetry (ITC), ultraviolet absorption (UV), fluorescence spectroscopy (FS) and circular dichroism (CD). Thermodynamic parameters, i.e., equilibrium constants, standard changes of enthalpy (Δ H°), Gibbs free energy (Δ G°) and entropy (Δ S°), for the binding process of the drug to the bio-macromolecules have been derived from the calorimetric data. Analysis of the thermodynamic data indicates that there are two classes of binding sites on the DNA molecules being able to coordinate with BET molecules. One class of binding takes place at the sites formed by base pairs, which is synergistically driven by enthalpy and entropy, while the other one takes place on phosphate groups and shown as an entropy driven process. The thermodynamic behavior of the DNA–drug supramolecular system has been discussed in the light of the important weak interactions, hydrophobic force, hydrogen bond and electrostatic force, according to the UV, FS and CD spectra.

Thermodynamic and spectrographic studies on the interactions of ct-DNA with 5-fluorouracil and tegafur

The interactions of calf thymus deoxyribonucleic acid (ct-DNA) with two antitumour drugs (5-fluorouracil and tegafur) in aqueous buffer solution (pH 7.40) have been investigated using nano-watt-scale isothermal titration calorimetry (ITC), circular dichroism (CD), ultraviolet absorption (UV) and fluorescence spectroscopy. Thermodynamic parameters, i.e., binding proportions and constants, standard changes of enthalpy (Δ H°), Gibbs free energy (Δ G°) and entropy (Δ S°) have been derived from the calorimetric data. The binding ratios of 5-fluorouracil and tegafur with base pairs in ct-DNA are 1:3 and 1:4, respectively. The thermodynamic parameters have been discussed according to the influence of drugs on molecular structure of the DNA shown spectrogram. The results indicate that molecule of 5-fluorouracil or tegafur can intercalate itself into the intra-molecular space formed by DNA double helix and cause some changes in the secondary structure of DNA molecule.

Laser ablation of powdered samples and analysis by means of laser-induced breakdown spectroscopy

The presented work proves the capacities of laser-induced breakdown spectroscopy (LIBS) as a fast, universal, and versatile technique for analysis of complex materials as ceramics. This paper reports on the analysis of ceramic raw materials (brick clays and kaolin) submitted to laser ablation in the form of pressed pellets. Spectrographic study was provided by standard single-pulse LIBS technique and orthogonal reheating double-pulse LIBS. It was found that both methods are comparable in terms of analytical performance, if adequate experimental parameters and signal detection systems are used.

Phonation in the newborn, infant cry

Sound spectrographic studies have shown that the crying of newborn infants has a fundamental frequency of about 400–600 cycles per second, and mostly a slightly rising–falling melody contour. In sick infants, and especially those with diseases affecting the central nervous system, abnormal cry characteristics occur. The fundamental frequency has been increased, and the melody contour is unstable. Various cry characteristics, which rarely occur in cries of healthy infants, are more often present in cries of the sick ones. Studies of cries in newborn infants have been especially aimed to determine whether cry analysis could be successful in diagnostics and in the early detection of the infant at risk for developmental difficulties.

GHRS Observations of Cool Low‐Gravity Stars. III. Plasma Flows and Turbulence in the Outer Atmosphere of α Orionis (M2 Iab)

We present the results of a Goddard High Resolution Spectrograph (GHRS) study of flow and turbulent velocities in the outer atmosphere of the M2 Iab supergiant α Ori. Ions with observed chromospheric emission features include C I, C II, Si I, Si II, O I, Co II, Al II, Mg II, Cr II, Fe I, and Fe II, while the photospheric absorption spectrum is dominated by Fe I. The widths of optically thin lines of C II], Si II], Co II, and Fe II indicate an average chromospheric turbulent velocity (Doppler FWHM) in the range of 31-35 km s-1, which is substantially above the expected chromospheric sound velocity. The shape of the C II] profiles indicates that this turbulence is probably anisotropically distributed, with velocities preferentially directed along and/or perpendicular to the radial direction. The radial velocity of near-UV Fe I photospheric absorption lines averaged 18 km s-1, somewhat smaller than the systemic RV of α Ori itself (21 km s-1) and significantly smaller than the RV of the optical Fe I lines (23 km s-1) at the time of the HST observations. The various components of the chromospheric emission lines had radial velocities in the range 7-36 km s-1. The emission wings for most of the ionic species averaged ~20 km s-1, i.e., they were nominally at rest with regard to the star. The central absorption features in these lines, however, showed lower velocities, averaging ~16 km s-1. The radial velocity of the central reversals in the stronger lines was also found to be correlated with the opacity of the lines, changing from ~20 km s-1 for the lower opacity lines to ~14 km s-1 for the higher opacity lines. This implies that we are directly viewing the acceleration of the stellar wind in the chromosphere from rest to about 7 km s-1. Contrary to the results reported earlier by Carpenter (1984) on the basis of IUE data, there is no indication of a deceleration of the wind at large distances from the star.

Spectrographic studies on the radioresistance of Miltex® and Miltefosine

Hintergrund Bei gleichzeitiger Anwendung von Miltex® und Strahlentherapie zur lokalen Kombinationsbehandlung von Lokalrezidiven/Hautmetastasen bei Mammakarzinompatienten stellt sich die Frage, wie strahlenresistent das neue Zytostatikum ist. Die Beantwortung dieser Frage ist wegen langer Penetrationszeiten des Wirkstoffs Miltefosin bedeutsam fur den Zeitpunkt der externen Anwendung von Miltex®.

The gestural organization of vowels: A cinefluorographic study of articulator gestures in Greenlandic

Movements of individual articulators are analyzed to elucidate principles of gestural organization in vowels. Procedures for tracking articulator gestures from x-ray motion films, and results obtained on coarticulation in Swedish, Bulgarian, and Greenlandic are reported in Wood [J. Phon. 19, 281–292 (1991); Proc. 3rd Congr. I. C. P. L. A. 191–200, Helsinki (1994); Proc. 13th I. C. Ph. Sc. 1, 392–395, Stockholm (1995); J. Phon. 24, 139–164 (1996); Proc. 4th Speech Prod. Seminar 61–64, Grenoble (1996)]. Tongue body movement was organized as predicted from a spectrographic study of Greenlandic vowels in Wood [Working Papers 4, 58–94, Lund (1971)] and according to the principles reported for English and Arabic in Wood [J. Phon. 7, 25–43 (1979)]. Greenlandic has three vowel phonemes, but the allophonic variation means all four tongue body gestures (palatal, velar, uvular, pharyngeal) are utilized. All articulator gestures needed for a vowel converged on a typical configuration, those arriving earlier being held until all were in position. The configuration was held briefly before the articulators were withdrawn. Coarticulation was organized by queuing oncoming gestures that are antagonistic to current gestures, avoiding conflicts.

Acoustic and Perceptual Study of Hindi Vowels in Consonantal Context

Effect of consonant environments on Hindi vowels in non-meaningful syllables have been studied. The measurement of fundamental and formant frequencies were carefully carried from syllable spectrograms obtained using Kay's Sona-Graph 7029-A. The calibration of equipment, measurement techniques and details of acoustic study are described. The study involves 21 speakers and 15 listeners in /hVd/ context, one distinct speaker each for the spectrographic pilot studies for the two sets of CVC and VCV syllables. The results of spectrographic analyses and perception tests carried out for the /hVd/ tokens indicate that there is little systematic acoustic variation in these three contexts due to the different consonantal environments.