scholarly journals Effect of Additive of Polymetallic Ores’ Tailin gs on Properties of Composite Cements

2016 ◽  
Vol 18 (2) ◽  
pp. 153 ◽  
Author(s):  
A.Zh. Aymenov ◽  
N.B. Sarsenbayev ◽  
T.M. Khudyakova ◽  
B.K. Sarsenbayev ◽  
A.T. Batyrkhanov ◽  
...  
Keyword(s):  
High Strength ◽  
Chemical Processes ◽  
High Tech ◽  
X Rays ◽  
Protective Properties ◽  
X Ray ◽  
Physical Chemical ◽  
Technological Production ◽  
Composite Cements ◽  
Positive Effect

The article analyzes the use of polymetallic ores’ tailings as a basis for production of composite cements and concrete, having protective properties against gamma and X-rays radiation, as well as high strength and lifetime. The main practically significant result is: the development of scientific and technological production bases of new high-tech type of multicomponent hydraulic binders for concretes – composite cements; the identification of new hydration products in composite cements with addition of polymetallic ores’ tailings; the development of optimal compositions of composite cements for concretes. It is established that the composite cements, that developed by us on the basis of polymetallic ores’ tailings, meet modern requirements i.e. its improve the construction-technical properties of material, have positive effect to the environment situation and allow to reduce the production cost of the final product. Their technology is low metal-intensive and<br />power-consuming. Studies of physical-chemical processes of composite cements structure formation with addition of polymetallic ores’ tailings have been conducted using methods such as chemical, X-ray phase, differential-thermal and electronmicroscopic analysis methods.

Systems Based on Physical-Chemical Processes

2017 ◽  
pp. 43-75
Author(s):  
August Bonmatí-Blasi ◽  
Míriam Cerrillo-Moreno ◽  
Victor Riau-Arenas
Keyword(s):  
Membrane Separation ◽  
Treatment Plant ◽  
High Strength ◽  
Resource Depletion ◽  
Nutrient Content ◽  
Chemical Processes ◽  
Waste Streams ◽  
Physical Chemical ◽  
Soil Emissions ◽  
Struvite Precipitation

High strength waste streams, namely rejected water from a wastewater treatment plant, livestock slurry, and agro-food wastewater, are characterized by its high organic matter and nutrient content which favours processes aiming to recover energy and nutrients, instead of removing them. In this regard physical-chemical processes are suitable technologies to attain these objectives. Among others, stripping coupled with absorption, struvite precipitation, membrane separation, and vacuum evaporation, are all physical-chemical processes aiming to concentrate nutrients in a stream that can later be reused as fertilizer. In this chapter the main physical-chemical processes will be defined and described in terms of the objective of each process technique, their theoretical fundamentals, environmental effects (air, water and soil emissions, resource depletion), technical indicators (efficiencies, energy consumption, etc.), and by-product characteristics.

scholarly journals Interstellar Chemistry: Radiation, Dust and Metals

2008 ◽  
Vol 4 (S255) ◽  
pp. 238-245
Author(s):  
Marco Spaans
Keyword(s):  
Milky Way ◽  
Large Fraction ◽  
Chemical Processes ◽  
Molecular Gas ◽  
X Rays ◽  
Feedback Effects ◽  
Interstellar Chemistry ◽  
X Ray ◽  
Metal Abundances ◽  
Dust Surface

AbstractAn overview is given of the chemical processes that occur in primordial systems under the influence of radiation, metal abundances and dust surface reactions. It is found that radiative feedback effects differ for UV and X-ray photons at any metallicity, with molecules surviving quite well under irradiation by X-rays. Starburst and AGN will therefore enjoy quite different cooling abilities for their dense molecular gas. The presence of a cool molecular phase is strongly dependent on metallicity. Strong irradiation by cosmic rays (>200× the Milky Way value) forces a large fraction of the CO gas into neutral carbon. Dust is important for H2 and HD formation, already at metallicities of 10−4 − 10−3 solar, for electron abundances below 10−3.

scholarly journals Comparative study of the around-Fermi electronic structure of 5d metals and metal-oxides by means of high-resolution X-ray emission and absorption spectroscopies

2020 ◽  
Vol 27 (3) ◽  
pp. 689-694 ◽  
Author(s):  
Anna Wach ◽  
Jacinto Sá ◽  
Jakub Szlachetko
Keyword(s):  
Mechanical Properties ◽  
Working Conditions ◽  
Electronic States ◽  
Theoretical Modelling ◽  
X Rays ◽  
Oxide Materials ◽  
X Ray ◽  
Physical Chemical ◽  
Tungsten Metal

The composition of occupied and unoccupied electronic states in the vicinity of Fermi energies is vital for all materials and relates to their physical, chemical and mechanical properties. This work demonstrates how the combination of resonant and non-resonant X-ray emission spectroscopies supplemented with theoretical modelling allows for quantitative analysis of electronic states in 5d transition metal and metal-oxide materials. Application of X-rays provides element selectivity that, in combination with the penetrating properties of hard X-rays, allows determination of the composition of electronic states under working conditions, i.e. non-vacuum environment. Tungsten metal and tungsten oxide are evaluated to show the capability to simultaneously assess composition of around-band-gap electronic states as well as the character and magnitude of the crystal field splitting.

Systems Based on Physical-Chemical Processes

2020 ◽  
pp. 526-558
Author(s):  
August Bonmatí-Blasi ◽  
Míriam Cerrillo-Moreno ◽  
Victor Riau-Arenas
Keyword(s):  
Membrane Separation ◽  
Treatment Plant ◽  
High Strength ◽  
Resource Depletion ◽  
Nutrient Content ◽  
Chemical Processes ◽  
Waste Streams ◽  
Physical Chemical ◽  
Soil Emissions ◽  
Struvite Precipitation

High strength waste streams, namely rejected water from a wastewater treatment plant, livestock slurry, and agro-food wastewater, are characterized by its high organic matter and nutrient content which favours processes aiming to recover energy and nutrients, instead of removing them. In this regard physical-chemical processes are suitable technologies to attain these objectives. Among others, stripping coupled with absorption, struvite precipitation, membrane separation, and vacuum evaporation, are all physical-chemical processes aiming to concentrate nutrients in a stream that can later be reused as fertilizer. In this chapter the main physical-chemical processes will be defined and described in terms of the objective of each process technique, their theoretical fundamentals, environmental effects (air, water and soil emissions, resource depletion), technical indicators (efficiencies, energy consumption, etc.), and by-product characteristics.

scholarly journals Properties of Wolf-Rayet stars from X-ray to radio data

1999 ◽  
Vol 193 ◽  
pp. 1-12
Author(s):  
Allan J. Willis
Keyword(s):  
Mass Loss ◽  
Chemical Separation ◽  
Spherically Symmetric ◽  
X Rays ◽  
Spectral Indices ◽  
X Ray ◽  
Radio Data ◽  
Physical Chemical ◽  
Data Yield ◽  
The Impact

This review outlines the impact of observations across the spectrum (X-rays to radio) on our understanding of the basic physical, chemical, wind and mass loss properties of Wolf-Rayet stars. Optical spectropolarimetry indicates that ∼ 15% of the WR stars have anisotropic winds, whilst the majority have globally spherically symmetric outflows. All WR stars probably have winds structured (clumped) on the smaller scale as evidenced from: thermal radio spectral indices, optical-UV continuum/line/polarisation variablity and time-series spectroscopy, and the ubiquity of wind X-ray emission. ROSAT results indicate LX(WR) = 1031–33 ergs−1 with kT ≃ 0.3keV. WR mass loss rates may be lower than previously thought: mean, clumping-corrected rates from radio data yield M(WN) ≃ 3 × 10−5 M⊙ yr−1 and M(WC) ≃ 2 × 10−5 M⊙ yr−1. Analyses of UV-optical-IR spectra lead to good constraints on Teff and L/L⊙ and confirm the chemical separation of the WN and WC classes: WN stars show H-He-C-N abundances reflecting CNO-burning products, and WC(WO) stars show He-burning products. ISO data are confirming the H-deficiency of WC winds, and reveal a substantially enhanced Neon abundance in WC stars.

A Comparison of Diffraction Elastic Constants of Steel Measured With X-Rays and Neutrons

1987 ◽  
Vol 31 ◽  
pp. 245-253 ◽  
Author(s):  
P. J. Rudnik ◽  
A. D. Krawitz ◽  
D. G. Reichel ◽  
J. B. Cohen
Keyword(s):  
Elastic Constants ◽  
Bulk Material ◽  
Measurement Techniques ◽  
High Strength ◽  
Uniaxial Tensile ◽  
X Rays ◽  
Near Surface ◽  
X Ray ◽  
Statistical Errors ◽  
Standard Deviations

AbstractThe diffraction elastic constants have been measured for the 211 and 310 peaks of a high-strength, low-alloy ferritic steel using X-rays and neutrons. The X-ray measurements were performed using both a uniaxial tension and a bending device. The neutron measurements were performed using a uniaxial tensile device. Ten X-ray and four neutron measurements were made for each case. Statistical errors were calculated and compared with the standard deviations of the average values. In addition, neutron measurements were made for the 310 peak utilizing an interior probe volume.The results indicate that the calculated statistical errors and the observed standard deviations were almost the same for each radiation. The X-ray and neutron tensile device measurements yielded similar results within experimental error. Furthermore, the X-ray tensile and bending results were similar as were the neutron internal volume measurements. These results suggest that near-surface X-ray measurements adequately sample the bulk material in the case of steel, and that different measurement techniques can be used to obtain reliable diffraction elastic constants.

scholarly journals FURTHER OBSERVATIONS ON THE INFLUENCE OF SALTS WHEN INJECTED INTO THE ANIMAL BODY

1923 ◽  
Vol 5 (3) ◽  
pp. 359-364
Author(s):  
Raymond G. Hussey
Keyword(s):  
Chemical Nature ◽  
X Rays ◽  
X Ray ◽  
Animal Body ◽  
Physiological Processes ◽  
Physical Chemical ◽  
Ion Effects ◽  
Chemical Conditions ◽  
Ray Effects ◽  
Interesting Analogy

A satisfactory correlation of our observations dealing with the influence of salts and those dealing with the influence of x-rays is not possible at present. Any far reaching conclusion is not permitted because the information we have at this time regarding the physical chemical conditions concerned in the process of injury, as well as that pertaining to the nature of radio-chemical reactions, is too meager. As far as the experiments with salts are concerned, it may be said that we are dealing with ion effects, and their importance in physiological processes is made clear by the investigations of Loeb (3) and those of Osterhout (4). The results that we have obtained in our experiments present an interesting analogy between the effect of x-rays and certain salts on the lymphoid elements of the animal body. We regard this analogy as significant in that it presents suggestions regarding the chemical nature of x-ray effects in the animal body.

White-Light Coronal Structures: Streamers and CMEs

1994 ◽  
Vol 144 ◽  
pp. 82
Author(s):  
E. Hildner
Keyword(s):  
Emission Line ◽  
Electron Density ◽  
White Light ◽  
Coronal Mass Ejections ◽  
X Rays ◽  
Solar Cycles ◽  
Temperature Function ◽  
X Ray ◽  
Eclipse Observations ◽  
Coronal Structures

AbstractOver the last twenty years, orbiting coronagraphs have vastly increased the amount of observational material for the whitelight corona. Spanning almost two solar cycles, and augmented by ground-based K-coronameter, emission-line, and eclipse observations, these data allow us to assess,inter alia: the typical and atypical behavior of the corona; how the corona evolves on time scales from minutes to a decade; and (in some respects) the relation between photospheric, coronal, and interplanetary features. This talk will review recent results on these three topics. A remark or two will attempt to relate the whitelight corona between 1.5 and 6 R⊙to the corona seen at lower altitudes in soft X-rays (e.g., with Yohkoh). The whitelight emission depends only on integrated electron density independent of temperature, whereas the soft X-ray emission depends upon the integral of electron density squared times a temperature function. The properties of coronal mass ejections (CMEs) will be reviewed briefly and their relationships to other solar and interplanetary phenomena will be noted.

Chemical Species Identification in an SEM by Changes in Emitted X-Ray Energies

1974 ◽  
Vol 32 ◽  
pp. 570-571
Author(s):  
R. H. Duff
Keyword(s):  
Species Identification ◽  
Valence Electron ◽  
Chemical Species ◽  
X Rays ◽  
Chemical Bonds ◽  
Small Shift ◽  
X Ray ◽  
Electron Transitions ◽  
Peak Energy ◽  
Chemical Combination

A material irradiated with electrons emits x-rays having energies characteristic of the elements present. Chemical combination between elements results in a small shift of the peak energies of these characteristic x-rays because chemical bonds between different elements have different energies. The energy differences of the characteristic x-rays resulting from valence electron transitions can be used to identify the chemical species present and to obtain information about the chemical bond itself. Although these peak-energy shifts have been well known for a number of years, their use for chemical-species identification in small volumes of material was not realized until the development of the electron microprobe.

Influence of X-Ray Induced Fluorescence on Energy Dispersive X-Ray Analysis of Thin Foils

1977 ◽  
Vol 35 ◽  
pp. 328-329
Author(s):  
E. A. Kenik ◽  
J. Bentley
Keyword(s):  
Thin Foil ◽  
Electron Excitation ◽  
Simple Approach ◽  
Foil Thickness ◽  
X Rays ◽  
X Ray ◽  
Hole Spectrum ◽  
Illumination System ◽  
Thin Foils ◽  
Intensity Ratios

Cliff and Lorimer (1) have proposed a simple approach to thin foil x-ray analy sis based on the ratio of x-ray peak intensities. However, there are several experimental pitfalls which must be recognized in obtaining the desired x-ray intensities. Undesirable x-ray induced fluorescence of the specimen can result from various mechanisms and leads to x-ray intensities not characteristic of electron excitation and further results in incorrect intensity ratios.In measuring the x-ray intensity ratio for NiAl as a function of foil thickness, Zaluzec and Fraser (2) found the ratio was not constant for thicknesses where absorption could be neglected. They demonstrated that this effect originated from x-ray induced fluorescence by blocking the beam with lead foil. The primary x-rays arise in the illumination system and result in varying intensity ratios and a finite x-ray spectrum even when the specimen is not intercepting the electron beam, an ‘in-hole’ spectrum. We have developed a second technique for detecting x-ray induced fluorescence based on the magnitude of the ‘in-hole’ spectrum with different filament emission currents and condenser apertures.

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