scholarly journals DSC reveals variation in enthalpy associated with free water molecules in water-ethanol solution exposed to x-rays and magnetic field

2021 ◽  
Vol 17 (1) ◽  
pp. 07-07
Author(s):  
Nirmal Chandra Sukul ◽  
Tandra Sarkar ◽  
Atheni Konar ◽  
Md. Amir Sohel ◽  
Asmita Sengupta ◽  
...  
Keyword(s):  
Magnetic Field ◽  
Aqueous Ethanol ◽  
Free Water ◽  
Ethanol Solution ◽  
Water Molecules ◽  
X Rays ◽  
Standard Medium ◽  
Scanning Calorimetry ◽  
X Ray ◽  
Homeopathic Drugs

Aqueous ethanol is the standard medium for all drugs used in homeopathy. X-ray and Magnetispoli ambo are 2 homeopathic drugs prepared by exposure of aqueous ethanol to x-rays and static magnetic field, respectively.Mother tinctures (MT)weresuccessively diluted with solvent 1:100 and succussed in several steps to prepare centesimal potencies 8 cH, 14 cH and 32 cH. The solvent was processed in the same way. Although identical in chemical composition (0.03 molar ethanol) and water content (96%) these preparations like the Mother tinctures and three potencies of X-ray and Magnetispoli amboexhibit different therapeutic pathological effects. Potency 8cH of each preparation was diluted with water to reach concentrations 4%, 20%, 40% and 80% ethanol. The aim of the study was to establish whether these potencies exhibited variation in free water molecules. Differential Scanning Calorimetry (DSC) of MT and potencies exhibited almost similar freezing and melting points, but they remarkably differed in freezing and melting enthalpy and free water molecules. The various dilutions of potency 8cH exhibited variation in enthalpies and free water molecules, being this variation independent of the amount of water added. We conclude that exposure of aqueous ethanol to x-rays and magnetic field, with subsequent dilution and agitation induces changes in the solvent involving free water molecules. All X-ray and Magnetispoli ambo potencies were analyzed by means of Raman spectroscopy for free water molecules. The results were compared to the ones of DSC, being more or less similar.

BOUND WATER, INOSITOL, AND THE EFFECT OF X-RAYS ON ESCHERICHIA COLI

1964 ◽  
Vol 10 (6) ◽  
pp. 877-885 ◽  
Author(s):  
S. J. Webb ◽  
M. D. Dumasia
Keyword(s):  
Escherichia Coli ◽  
Bound Water ◽  
Free Water ◽  
Sharp Decrease ◽  
Water Molecules ◽  
X Rays ◽  
X Ray ◽  
Water Layers ◽  
The Difference ◽  
Escherichia Coli B

Aerosols of Escherichia coli B were subjected to 250 kv X-rays. It was found that maximal X-ray damage occurred at 70 to 80% relative humidity (R.H.). At these R.H. values only the water bound directly to cell macromolecules remains, and if the water layers were increased by using higher humidities, X-ray damage decreased. Also, at R.H. levels below 70% a sharp decrease in the sensitivity of the cells to the radiation occurred. Several chemicals known to protect cells against desiccation, ultraviolet, and X-ray damage were examined and of these i-inositol proved the most successful. The difference in the protective ability of these various compounds indicated that some protect cells against desiccation damage by retaining water, others by replacing bound-water molecules in macromolecular structure but those retaining water will not protect against X-rays. The results suggest that the physical removal or ionization of a strategic bound-water molecule by X-rays causes most of the cell deaths rather than ionizations occurring in the free water as the presence of the latter appears to offer cells a measure of protection.

scholarly journals Is Micro X-ray Computer Tomography a Suitable Non-Destructive Method for the Characterisation of Dental Materials?

Polymers ◽  
2021 ◽  
Vol 13 (8) ◽  
pp. 1271
Author(s):  
Andreas Koenig ◽  
Leonie Schmohl ◽  
Johannes Scheffler ◽  
Florian Fuchs ◽  
Michaela Schulz-Siegmund ◽  
...  
Keyword(s):  
Flexural Strength ◽  
Computer Tomography ◽  
Mechanical Performance ◽  
Dental Materials ◽  
Three Dimensional ◽  
X Rays ◽  
Scanning Calorimetry ◽  
X Ray ◽  
Multiple Measurements ◽  
High Doses

The aim of the study was to investigate the effect of X-rays used in micro X-ray computer tomography (µXCT) on the mechanical performance and microstructure of a variety of dental materials. Standardised bending beams (2 × 2 × 25 mm3) were forwarded to irradiation with an industrial tomograph. Using three-dimensional datasets, the porosity of the materials was quantified and flexural strength was investigated prior to and after irradiation. The thermal properties of irradiated and unirradiated materials were analysed and compared by means of differential scanning calorimetry (DSC). Single µXCT measurements led to a significant decrease in flexural strength of polycarbonate with acrylnitril-butadien-styrol (PC-ABS). No significant influence in flexural strength was identified for resin-based composites (RBCs), poly(methyl methacrylate) (PMMA), and zinc phosphate cement (HAR) after a single irradiation by measurement. However, DSC results suggest that changes in the microstructure of PMMA are possible with increasing radiation doses (multiple measurements, longer measurements, higher output power from the X-ray tube). In summary, it must be assumed that X-ray radiation during µXCT measurement at high doses can lead to changes in the structure and properties of certain polymers.

scholarly journals Investigating the Magnetospheres of Rapidly Rotating B-type Stars

2016 ◽  
Vol 12 (S329) ◽  
pp. 369-372
Author(s):  
C. L. Fletcher ◽  
V. Petit ◽  
Y. Nazé ◽  
G. A. Wade ◽  
R. H. Townsend ◽  
...  
Keyword(s):  
Magnetic Field ◽  
Magnetic Fields ◽  
Centrifugal Force ◽  
Point Of View ◽  
Closed Field ◽  
Theoretical Point ◽  
X Rays ◽  
Rapid Rotation ◽  
X Ray ◽  
Surface Magnetic Field

AbstractRecent spectropolarimetric surveys of bright, hot stars have found that ~10% of OB-type stars contain strong (mostly dipolar) surface magnetic fields (~kG). The prominent paradigm describing the interaction between the stellar winds and the surface magnetic field is the magnetically confined wind shock (MCWS) model. In this model, the stellar wind plasma is forced to move along the closed field loops of the magnetic field, colliding at the magnetic equator, and creating a shock. As the shocked material cools radiatively it will emit X-rays. Therefore, X-ray spectroscopy is a key tool in detecting and characterizing the hot wind material confined by the magnetic fields of these stars. Some B-type stars are found to have very short rotational periods. The effects of the rapid rotation on the X-ray production within the magnetosphere have yet to be explored in detail. The added centrifugal force due to rapid rotation is predicted to cause faster wind outflows along the field lines, leading to higher shock temperatures and harder X-rays. However, this is not observed in all rapidly rotating magnetic B-type stars. In order to address this from a theoretical point of view, we use the X-ray Analytical Dynamical Magnetosphere (XADM) model, originally developed for slow rotators, with an implementation of new rapid rotational physics. Using X-ray spectroscopy from ESA’s XMM-Newton space telescope, we observed 5 rapidly rotating B-types stars to add to the previous list of observations. Comparing the observed X-ray luminosity and hardness ratio to that predicted by the XADM allows us to determine the role the added centrifugal force plays in the magnetospheric X-ray emission of these stars.

scholarly journals Radio and X-ray connection in radio mini-halos: Implications for hadronic models

2020 ◽  
Vol 640 ◽  
pp. A37 ◽  
Author(s):  
A. Ignesti ◽  
G. Brunetti ◽  
M. Gitti ◽  
S. Giacintucci
Keyword(s):  
Magnetic Field ◽  
Large Fraction ◽  
Cosmic Ray ◽  
Physical Parameters ◽  
Model Parameters ◽  
Relativistic Electrons ◽  
X Rays ◽  
X Ray ◽  
Hadronic Model ◽  
Radio Halos

Context. A large fraction of cool-core clusters are known to host diffuse, steep-spectrum radio sources, called radio mini-halos, in their cores. Mini-halos reveal the presence of relativistic particles on scales of hundreds of kiloparsecs, beyond the scales directly influenced by the central active galactic nucleus (AGN), but the nature of the mechanism that produces such a population of radio-emitting, relativistic electrons is still debated. It is also unclear to what extent the AGN plays a role in the formation of mini-halos by providing the seeds of the relativistic population. Aims. In this work we explore the connection between thermal and non-thermal components of the intra-cluster medium in a sample of radio mini-halos and we study the implications within the framework of a hadronic model for the origin of the emitting electrons. Methods. For the first time, we studied the thermal and non-thermal connection by carrying out a point-to-point comparison of the radio and the X-ray surface brightness in a sample of radio mini-halos. We extended the method generally applied to giant radio halos by considering the effects of a grid randomly generated through a Monte Carlo chain. Then we used the radio and X-ray correlation to constrain the physical parameters of a hadronic model and we compared the model predictions with current observations. Results. Contrary to what is generally reported in the literature for giant radio halos, we find that the mini-halos in our sample have super-linear scaling between radio and X-rays, which suggests a peaked distribution of relativistic electrons and magnetic field. We explore the consequences of our findings on models of mini-halos. We use the four mini-halos in the sample that have a roundish brightness distribution to constrain model parameters in the case of a hadronic origin of the mini-halos. Specifically, we focus on a model where cosmic rays are injected by the central AGN and they generate secondaries in the intra-cluster medium, and we assume that the role of turbulent re-acceleration is negligible. This simple model allows us to constrain the AGN cosmic ray luminosity in the range ∼1044−46 erg s−1 and the central magnetic field in the range 10–40 μG. The resulting γ-ray fluxes calculated assuming these model parameters do not violate the upper limits on γ-ray diffuse emission set by the Fermi-LAT telescope. Further studies are now required to explore the consistency of these large magnetic fields with Faraday rotation studies and to study the interplay between the secondary electrons and the intra-cluster medium turbulence.

scholarly journals Thermal and non-thermal connection in radio mini-halos

2018 ◽  
Vol 14 (S342) ◽  
pp. 137-140
Author(s):  
A. Ignesti ◽  
G. Brunetti ◽  
M. Gitti ◽  
S. Giacintucci
Keyword(s):  
Magnetic Field ◽  
Surface Brightness ◽  
X Rays ◽  
X Ray ◽  
Point Analysis ◽  
Spectrum Radio ◽  
Point To Point ◽  
The Magnetic Field ◽  
Relativistic Particles ◽  
Open Issues

AbstractSeveral cool-core clusters are known to host a radio mini-halo, a diffuse, steep-spectrum radio source located in their cores, thus probing the presence of non-thermal components as magnetic field and relativistic particles on scales not directly influenced by the central AGN. The nature of the mechanism that produces a population of radio-emitting relativistic particles on the scale of hundreds of kiloparsecs is still unclear. At the same time, it is still debated if the central AGN may play a role in the formation of mini-halos by providing the seed of the relativistic particles. We aim to investigate these open issues by studying the connection between thermal and non-thermal components of the intra-cluster medium. We performed a point-to-point analysis of the radio and the X-ray surface brightness of a compilation of mini-halos. We find that mini-halos have super-linear scalings between radio and X-rays, with radio brightness declining more steeply than the X-ray brightness. This trend is opposite to that generally observed in giant radio halos, thus marking a possible difference in the physics of the two radio sources. Finally, using the scalings between radio and X-rays and assuming a hadronic origin of mini-halos we derive constraints on the magnetic field in the core of the hosting clusters.

scholarly journals Synthesis, Characterization, and Thermal Decomposition of Pure and Dysprosium Doped Yttrium Phosphate System

2013 ◽  
Vol 2013 ◽  
pp. 1-8 ◽  
Author(s):  
K. K. Bamzai ◽  
Nidhi Kachroo ◽  
Vishal Singh ◽  
Seema Verma
Keyword(s):  
Thermogravimetric Analysis ◽  
Ammonium Hydroxide ◽  
Xrd Analysis ◽  
Lattice Parameter ◽  
Energy Dispersive ◽  
Water Molecules ◽  
X Ray Diffraction ◽  
Scanning Calorimetry ◽  
Structural Investigations ◽  
X Ray

Yttrium phosphate and dysprosium doped yttrium phosphate were synthesized from aqueous solutions using rare earth chloride, phosphoric acid, and traces of ammonium hydroxide. The synthesized material was then characterized for their structural investigations using powder X-ray diffraction (XRD) analysis and scanning electron microscopy (SEM) supplemented with energy dispersive X-ray analysis (EDAX). The spectroscopic investigations were carried out using Fourier transform infrared (FTIR) spectroscopy. The thermal stability was studied using differential thermogravimetric analysis (DTA), thermogravimetric analysis (TGA), and differential scanning calorimetry (DSC) techniques. X-ray diffraction analysis reveals that both yttrium phosphate and dysprosium doped yttrium phosphate belong to tetragonal system with lattice parameter  Å,  Å and  Å,  Å, respectively. The stoichiometry of the grown composition was established by energy dispersive X-ray analysis. The EDAX analysis suggests the presence of water molecules. The presence of water molecules along with orthophosphate group and metallic ion group was confirmed by FTIR analysis. Thermogravimetric analysis suggests that decomposition in case of yttrium phosphate takes place in three different stages and the final product stabilizes after 706°C, whereas in case of dysprosium doped yttrium phosphate the decomposition occurs in two different stages, and the final product stabilizes after 519°C.

scholarly journals Hydration Study of Synthetic Yeelimite using LXRPD and SXRPD

2014 ◽  
Vol 70 (a1) ◽  
pp. C1096-C1096
Author(s):  
Ana Cuesta ◽  
Gema Alvarez Pinazo ◽  
Angeles De la Torre ◽  
Susana Sanfélix ◽  
Inmaculada Peral ◽  
...  
Keyword(s):  
Standard Method ◽  
Internal Standard ◽  
Free Water ◽  
Ex Situ ◽  
Quantitative Phase Analysis ◽  
Internal Standard Method ◽  
X Rays ◽  
X Ray ◽  
External Standard Method

XRPD is a powerful tool for material characterization in general, and for in-situ studies of chemical processes in particular. The use of an intense X-ray source, .i.e. synchrotron X-rays, coupled with fast X-ray detection permits time-resolved diffraction experiments allowing in-situ quantitative phase analysis during the early ages of cement hydration. Calcium sulfoaluminate, CSA, cements may have variable compositions, but all of them contain high amounts of ye'elimite, Ca4Al6O12SO4. Commercial CSA cements have special applications such as high strength developments at early-ages. Ye'elimite is very reactive and most of its hydration heat is released during the first eight hours of hydration . The aim of this work is to better understand the early age hydration of stoichiometric (orthorhombic) and doped (pseudo-cubic) ye'elimite samples. The parameters studied by SXRPD, LXRPD and calorimetry have been: polymorphism; water/ye'elimite ratio; and sulfate (gypsum and anhydrite) contents. This work has allowed establishing mechanisms and kinetics for hydration of ye'elimite samples by in-situ SXRPD with internal standard methodology. Moreover, pastes were also studied by ex-situ LXRPD with the external standard method, G-factor, at 2 and 7 days. Both strategies were able to quantify the amorphous contents, including free water. It is important to highlight that the results obtained at early ages, by the internal standard method, are in agreement with those obtained at later ages, G-method, showing the consistence and complementarity of both methodologies. The hydration of stoichiometric ye'elimite in the presence of gypsum is strongly hastened, when compared to the hydration process without gypsum. However, the presence of gypsum has a little effect in the hydration of doped ye'elimite. Moreover, anhydrite has also accelerated the hydration of stoichiometric ye'elimite, although its lower solubility has provoked the formation of an intermediate phase in the first hours.

scholarly journals Impact of heating temperatures on the properties of instant cassava flour

2021 ◽  
Vol 39 (No. 5) ◽  
pp. 360-367
Author(s):  
Achmat Sarifudin ◽  
Enny Sholichah ◽  
Woro Setiaboma ◽  
Nok Afifah ◽  
Dewi Desnilasari ◽  
...  
Keyword(s):  
Heating Temperature ◽  
Ethanol Solution ◽  
Starch Granules ◽  
Dsc Analysis ◽  
X Ray Diffraction ◽  
Scanning Calorimetry ◽  
Cassava Flour ◽  
X Ray ◽  
The Matrix ◽  
The Impact

Native cassava flour can be modified to be instant flour by heating the cassava flour in ethanol solution. The impact of heating temperatures of 60, 80, and 100 °C (coded as ICF-60, ICF-80, and ICF-100) on the properties of instant cassava flour (ICF), including colour, morphological, and thermal properties, water absorption, and solubility indexes and pasting behaviour, were investigated. Results showed that ICF produced at higher temperatures exhibited lower lightness, higher redness, and yellowness values. ICF-60 and ICF-80 still displayed the granular forms and birefringence properties of native starches, while granules of ICF-100 were broken and partially lost their birefringence properties. Results of X-ray diffraction (XRD) technique and differential scanning calorimetry (DSC) analysis suggested that the amylopectin double helixes of crystalline regions within the structure of ICF orientated to more perfect conformation before they were disrupted at the highest heating temperature (100 °C). During hydration, the starch granules of ICF-60 and ICF-80 absorbed water into their granules; meanwhile, ICF-100 entrapped water within the matrix formed by the entanglements of ICF-100 particles. Results of pasting behaviour analysis indicated that ICF-60 and ICF-80 showed better thermal stability while ICF-100 exhibited the highest cold viscosity.

scholarly journals On Special Features of Non-Thermal Solar X Radiation above 10 keV

1972 ◽  
Vol 14 ◽  
pp. 761-762
Author(s):  
G. Elwert ◽  
E. Haug
Keyword(s):  
Magnetic Field ◽  
Angular Distribution ◽  
Power Law ◽  
Impulsive Phase ◽  
X Rays ◽  
Energetic Electrons ◽  
X Ray ◽  
Preferred Direction ◽  
Field Lines ◽  
The Magnetic Field

The polarization and angular distribution of solar hard X radiation above 10 keV was calculated under the assumption that the X rays originate as bremsstrahlung from energetic electrons moving in a preferred direction. The source electrons are supposed to have a power-law spectrum. These conditions are to be expected in the impulsive phase of an X-ray burst. The spiral orbits of the electrons around the magnetic field lines are taken into account.

scholarly journals The Cyclotron Lines in the Optical Spectra of the Stars of AM Herculis Group: Observations and Interpretation

1980 ◽  
Vol 88 ◽  
pp. 453-465 ◽  
Author(s):  
I. G. Mitrofanov
Keyword(s):  
Magnetic Field ◽  
Cataclysmic Variables ◽  
Magnetized Plasma ◽  
Close Binaries ◽  
X Rays ◽  
Observational Method ◽  
Ultraviolet Continuum ◽  
X Ray ◽  
Optical Continuum ◽  
Basic Prediction

The stars of the AM Herculis group (AM Her, VV Pup, AN UMa and 2A 0311-227) are close binaries containing a mass losing, nondegenerate star and an accreting degenerate dwarf. Their main properties are: the large linear and circular polarization of the optical light, high and low luminosity states, the variable emission line, spectra of H, He and other elements and the identification of these objects with X-ray sources. It is generally accepted that the strong magnetic field of the degenerate dwarf is responsible for these peculiar properties and for the distinction between these objects and the cataclysmic variables (Mitrofanov 1978, 1979a). The polarized optical continuum may be emitted by the accreted magnetized plasma (e.g. Chanmugam and Wagner, 1979), by the magnetized photosphere of the degenerate dwarf (Mitrofanov et al. 1977), or by both sources (Mitrofanov, 1979b). To explain the observed X-rays, Lamb and Masters (1979) showed that a magnetic field about 108 gs is necessary. Unfortunately, the basic prediction of their model - the strong ultraviolet continuum in the spectrum of AM Herculis - appears to be absent (Raymond et al. 1979). Chanmugam and Wagner (1979) proposed a rather different estimate for B of 2 · 108/m*gs (m* = 5 ÷ 25). For further investigations of the AM Herculis-type stars it seems useful to find a direct observational method for measuring the dwarfs′ magnetic fields.

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