scholarly journals Basic Materials Studies of Lanthanide Halide Scintillators

2007 ◽  
Vol 1038 ◽  
Author(s):  
F. P. Doty ◽  
Douglas McGregor ◽  
Mark Harrison ◽  
Kip Findley ◽  
Raulf Polichar ◽  
...  
Keyword(s):  
Gamma Ray ◽  
Materials Science ◽  
Low Cost ◽  
Large Diameter ◽  
Scale Up ◽  
Chemical Properties ◽  
Anisotropic Plasticity ◽  
Ongoing Work ◽  
Perfect Cleavage ◽  
Physical And Chemical

AbstractCerium and lanthanum tribromides and trichlorides form isomorphous alloys with the hexagonal UCl3 type structure, and have been shown to exhibit high luminosity and proportional response, making them attractive alternatives for room temperature gamma ray spectroscopy. However the fundamental physical and chemical properties of this system introduce challenges for material processing, scale-up, and detector fabrication. In particular, low fracture stress and perfect cleavage along prismatic planes cause profuse cracking during and after crystal growth, impeding efforts to scale this system for production of low cost, large diameter spectrometers. We have reported progress on basic materials science of the lanthanide halides. Studies to date have included thermomechanical and thermogravimetric analyses, hygroscopicity, yield strength, and fracture toughness. The observed mechanical properties pose challenging problems for material production and post processing; therefore, understanding mechanical behavior is key to fabricating large single crystals, and engineering of robust detectors and systems. Analysis of the symmetry and crystal structure of this system, including identification of densely-packed and electrically neutral planes with slip and cleavage, and comparison of relative formation and propagation energies for proposed slip systems, suggest possible mechanisms for deformation and crack initiation under stress. The low c/a ratio and low symmetry relative to traditional scintillators indicate limited and highly anisotropic plasticity cause redistribution of residual process stress to cleavage planes, initiating fracture. Ongoing work to develop fracture resistant lanthanide halides is presented.

Targeted Alternation in Properties of Solid Amorphous-Nanocrystalline Material in Exposing to Nanosecond Laser Radiation

2021 ◽  
Vol 410 ◽  
pp. 469-474
Author(s):  
Ivan S. Safronov ◽  
Alexander I. Ushakov
Keyword(s):  
Laser Radiation ◽  
Physical Properties ◽  
Materials Science ◽  
Chemical Properties ◽  
High Energy ◽  
Strength Properties ◽  
Nanosecond Laser ◽  
Processing Modes ◽  
Traditional Processing ◽  
Physical And Chemical

One of the most important purposes of materials science is the ability to govern the physical properties of materials characterized by different structures. The strength properties of nanostructured metal alloys do not always meet the exploitation requirements. The set of properties of such materials is stable within narrow limits: temperature, mechanical, and corrosion conditions. Traditional processing modes are ineffective for such materials. Attempts to use them often lead to the loss of unique physical and chemical properties. The most effective methods of processing such materials are associated with the use of laser radiation. The laser pulse has a number of features, including a complex effect on the surface layers of the material. Spot and short irradiation with high-energy rays can preserve the unique physical properties of samples as a whole and improve strength indicators without destroying the structure of the material as a whole.

scholarly journals Raman active modes of single-wall boron nitride nanotubes inside carbon nanotubes

2018 ◽  
Vol 3 (2) ◽  
Author(s):  
A.M. Nassir ◽  
Ah Rahmani ◽  
M. Boutahir ◽  
B. Fakrach ◽  
H. Chadli ◽  
...  
Keyword(s):  
Boron Nitride ◽  
Inelastic Neutron Scattering ◽  
Large Diameter ◽  
Chemical Properties ◽  
Spatial Dimension ◽  
Inelastic Neutron ◽  
Boron Nitride Nanotubes ◽  
Hybrid Nanostructures ◽  
Wave Number ◽  
Physical And Chemical

The structure of boron–nitride nanotubes (BNNTs) is very similar to that of CNTs, and they exhibit many similar physical and chemical properties. In particular, a single walled boron nitride nanotube (BNNT) and a single walled carbon nanotube (CNT) have been reported. The spectral moment’s method (SMM) was shown to be a powerful tool for determining vibrational spectra (infrared absorption, Raman scattering and inelastic neutron-scattering spectra) of harmonic systems. This method can be applied to very large systems, whatever the type of atomic forces, the spatial dimension, and structure of the material. The calculations of vibrational properties of BNNT@CNT double-walled hybrid nanostructures are performed in the framework of the force constants model, using the spectral moment's method (SMM). A Lennard–Jones potential is used to describe the van der Waals in-teractions between inner and outer tubes in hybrid systems. The calculation of the BNNT@CNT Raman active modes as a function of the diameter and chirality of the inner and outer tubes allows us to derive the diameter dependence of the wave number of the breathing-like modes, intermediate-like modes and tangential-like modes in a large diameter range. These predictions are useful to interpret the experimental data.

scholarly journals Some physical and chemical properties of substrates designed for container production of spruce (Picea abies (L) Karst)

2004 ◽  
pp. 79-90
Author(s):  
Vesna Vratusa
Keyword(s):  
Woody Plants ◽  
Low Cost ◽  
Chemical Properties ◽  
Foreign Markets ◽  
Urban Green Spaces ◽  
Nursery Production ◽  
Countries In Transition ◽  
Physical And Chemical ◽  
And Chemical Properties

Efficient nursery production of woody plants, as well as the level of their successful application in urban green spaces, greatly depends upon properties of substrates in which these individuals grow, develop and endure. Furthermore, quality of substrate does not only affect the quality of future product (plant individual or green space), but distinctly determines its price. This element, extremely significant for all countries in transition, thus Serbia as well, commands finding ways of making qualitative, but least expensive substrate. The most logical solution is to use mixtures/substrates of precisely defined properties, composed of domestic components. Results presented in this paper imply that it is possible to create precisely such standard mixtures from domestic resources at relatively low cost, adjusted to needs of particular species, which would ultimately lead to successful, non-expensive nursery production and application of produced stock, both on domestic and foreign markets.

scholarly journals M-Polynomials and Associated Topological Indices of Sodalite Materials

2021 ◽  
Vol 2021 ◽  
pp. 1-10
Author(s):  
Ghazanfar Abbas ◽  
Muhammad Ibrahim ◽  
Ali Ahmad ◽  
Muhammad Azeem ◽  
Kashif Elahi
Keyword(s):  
Greenhouse Gases ◽  
Topological Index ◽  
Low Cost ◽  
Chemical Properties ◽  
Topological Indices ◽  
Mathematical Tool ◽  
Physical And Chemical Properties ◽  
Natural Zeolites ◽  
Physical And Chemical ◽  
And Chemical Properties

Natural zeolites are commonly described as macromolecular sieves. Zeolite networks are very trendy chemical networks due to their low-cost implementation. Sodalite network is one of the most studied types of zeolite networks. It helps in the removal of greenhouse gases. To study this rich network, we use an authentic mathematical tool known as M-polynomials of the topological index and show some physical and chemical properties in numerical form, and to understand the structure deeply, we compare different legitimate M-polynomials of topological indices, concluding in the form of graphical comparisons.

Degradation of Colored Polystyrene Films

2018 ◽  
Vol 930 ◽  
pp. 254-257 ◽  
Author(s):  
Francisca Pereira de Araújo ◽  
Josy Anteveli Osajima ◽  
Mônica Regina Silva de Araujo ◽  
Edson Cavalcanti da Silva Filho ◽  
João Sammy Nery de Souza
Keyword(s):  
Crystal Violet ◽  
Carbonyl Compounds ◽  
Low Cost ◽  
Chemical Properties ◽  
Polymer Materials ◽  
Visible Radiation ◽  
No Formation ◽  
Crystal Violet Dye ◽  
Physical And Chemical ◽  
And Chemical Properties

Polystyrene is commercial polymer of extensive use in industrial scale due to great physical and chemical properties and low cost. Lifespan of polymer materials can be changed by incorporation of additions to polymeric matrix.The present study aimed to evaluate the influence of crystal violet dye in polystyrene matrices when irradiated by visible radiation. The samples were studied in the form of films, in which solution of crystal violet (5.0x10-4mol.L-1) was added to the PS solution (8% w / w). The films were irradiated with commercial lamp for 150 hours and analyzed with UV-Vis and FTIR. The results showed that the dye degraded at a rate of 16%, however the FTIR analysis revealed that polystyrene did not degrade under the conditions studied, since no formation of carbonyl compounds was observed.

scholarly journals Chitosan–Starch Films Modified with Natural Extracts to Remove Heavy Oil from Water

Water ◽  
2019 ◽  
Vol 12 (1) ◽  
pp. 17
Author(s):  
Jessica I. Lozano-Navarro ◽  
Nancy P. Díaz-Zavala ◽  
José A. Melo-Banda ◽  
Carlos Velasco-Santos ◽  
Francisco Paraguay-Delgado ◽  
...  
Keyword(s):  
Sorption Capacity ◽  
Heavy Oil ◽  
Low Cost ◽  
Chemical Properties ◽  
Clear Correlation ◽  
Natural Extracts ◽  
Water Ph ◽  
Starch Films ◽  
Gas Chromatography Mass Spectroscopy ◽  
Physical And Chemical

Chitosan films were used to remove heavy oil from connate water, deionized water, and seawater. In this research, chitosan–starch films were modified with natural extracts from cranberry, blueberry, beetroot, pomegranate, oregano, pitaya, and grape. These biodegradable, low-cost, eco-friendly materials show an important oil sorption capacity from different water conditions. It was observed that the sorption capacity has a clear correlation with the extract type, quantity, and water pH. In order to understand the physical and chemical properties of the films, they were analyzed according to their apparent density, water content, solubility, and swelling degree by scanning electron microscopy (SEM), thermogravimetric analysis (TGA), gas chromatography–mass spectroscopy (GC–MS), and the determination of surface area using the Brunauer Emmett Teller (BET) method. The results indicate that chitosan–starch films modified with natural extracts can be successfully applied for environmental issues such as oil spill remedy.

Study the Effects of Different Surfactants on Hydrophilicity of Polydimethylsiloxane (PDMS)

2012 ◽  
Author(s):  
Hojjat Madadi ◽  
Jasmina Casals-Terré
Keyword(s):  
Vapour Deposition ◽  
Low Cost ◽  
Chemical Vapour ◽  
Chemical Properties ◽  
Base Material ◽  
Hydrophobic Surface ◽  
Fabrication Procedure ◽  
Highly Hydrophobic ◽  
Physical And Chemical ◽  
And Chemical Properties

The outstanding characteristics of polydimethylsiloxane (PDMS) caused its extensive use as base material to manufacture microfluidic devices. PDMS has numerous advantages coming from instinct properties such as its low cost, simple fabrication procedure, and robust nature that make it a compatible material in many applications such as biological and biomedical engineering. In spite of favorable physical and chemical properties, hydrophobic surface of PDMS is sometimes debatable. Because of PDMS is highly hydrophobic, pumping aqueous solution through microchannels using only capillary forces might be difficult. Although many surface treatments methods have been proposed to modify and increase the hydrophilicity of PDMS [Oxygen plasma [1], UV-radiation [2], Silanization and Chemical vapour deposition [3],…], the use of surfactants is the most effective and easiest method to overcome the hydrophobicity compared to more complex protocols which require expensive facilities [4,5]. The hydrophilic behavior of surfactant-added PDMS and especially its biocompatibility has allowed many microfluidic bio-applications such as separation of biomolecules [6,7], blood cell separation [8] and cell-based assay [9,10]. This paper discusses about the efficiency of adding different surfactants on the wettability of PDMS.

Alternative Microturbine Fuels Feasibility Study Through Thermal Stability, Material Compatibility, and Engine Testing

2013 ◽  
Vol 135 (11) ◽  
Author(s):  
Sergio Arias Quintero ◽  
Joshua Schmitt ◽  
Richard Blair ◽  
Jayanta Kapat
Keyword(s):  
Thermal Stability ◽  
Alternative Fuels ◽  
Low Cost ◽  
Chemical Properties ◽  
Engine Performance ◽  
Negative Effects ◽  
Operation Costs ◽  
Turbine Performance ◽  
Engine Testing ◽  
Physical And Chemical

Historically, gas turbine fuels have been procured based on availability and low cost criteria. However,in the past few decades, with the growing concern over the negative environmental impacts produced by emissions, alternative fuels have been developed and tested under the objective of reducing such negative effects. The physical properties and broad chemical composition of fuels, including trace elements, may result in engine performance issues found only after extensive operation. This, in turn, results in higher maintenance and operation costs. This paper studies the feasibility of several renewable fuels for microturbine application, identifying key relationships between the physical and chemical properties, thermal stability, materials compatibility, and turbine performance.

scholarly journals In situ physical and chemical characterisation of the Eyjafjallajökull aerosol plume in the free troposphere over Italy

2014 ◽  
Vol 14 (2) ◽  
pp. 1075-1092 ◽  
Author(s):  
S. Sandrini ◽  
L. Giulianelli ◽  
S. Decesari ◽  
S. Fuzzi ◽  
P. Cristofanelli ◽  
...  
Keyword(s):  
Inductively Coupled Plasma ◽  
Gamma Ray ◽  
Fine Fraction ◽  
Chemical Properties ◽  
Analytical Techniques ◽  
Ground Level ◽  
Coarse Fraction ◽  
Volcanic Plume ◽  
Physical And Chemical ◽  
Aerosol Plume

Abstract. Continuous measurements of physical and chemical properties at the Mt. Cimone (Italy) GAW-WMO (Global Atmosphere Watch, World Meteorological Organization) Global Station (2165 m a.s.l.) have allowed the detection of the volcanic aerosol plume resulting from the Eyjafjallajökull (Iceland) eruption of spring 2010. The event affected the Mt. Cimone site after a transport over a distance of more than 3000 km. Two main transport episodes were detected during the eruption period, showing a volcanic fingerprint discernible against the free tropospheric background conditions typical of the site, the first from April 19 to 21 and the second from 18 to 20 May 2010. This paper reports the modification of aerosol characteristics observed during the two episodes, both characterised by an abrupt increase in fine and, especially, coarse mode particle number. Analysis of major, minor and trace elements by different analytical techniques (ionic chromatography, particle induced X-ray emission–particle induced gamma-ray emission (PIXE–PIGE) and inductively coupled plasma mass spectrometry (ICP-MS)) were performed on aerosols collected by ground-level discrete sampling. The resulting database allows the characterisation of aerosol chemical composition during the volcanic plume transport and in background conditions. During the passage of the volcanic plume, the fine fraction was dominated by sulphates, denoting the secondary origin of this mode, mainly resulting from in-plume oxidation of volcanic SO2. By contrast, the coarse fraction was characterised by increased concentration of numerous elements of crustal origin, such as Fe, Ti, Mn, Ca, Na, and Mg, which enter the composition of silicate minerals. Data analysis of selected elements (Ti, Al, Fe, Mn) allowed the estimation of the volcanic plume's contribution to total PM10, resulting in a local enhancement of up to 9.5 μg m−3, i.e. 40% of total PM10 on 18 May, which was the most intense of the two episodes. These results appear significant, especially in light of the huge distance of Mt. Cimone from the source, confirming the widespread diffusion of the Eyjafjallajökull ashes over Europe.

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