Binary niobium alloying with low-melting metals by precipitation of nanoparticles

2019 ◽  
pp. 40-48
Author(s):  
V. N. Volodin ◽  
Yu. Zh. Tuleushev ◽  
S. A. Trebukhov ◽  
A. V. Nitsenko ◽  
N. M. Burabaeva
Keyword(s):  
Solid Solution ◽  
Crystal Lattice ◽  
Liquid State ◽  
Thermal Fluctuation ◽  
The Body ◽  
Lattice Parameters ◽  
Metal Particles ◽  
Lead And Cadmium ◽  
Matrix Lattice ◽  
Melting Effect

Binary niobium alloys with tin, lead and cadmium were obtained by precipitation of nanosized metal particles dispersed in lowpressure plasma using the thermal fluctuation melting effect. The thermal fluctuation melting effect implies that a small particle is in the quasi-liquid state up to a certain critical size which, if exceeded due to steam condensation or fusion (coalescence) of other quasiliquid particles, results in the drop crystallization. The critical sizes of particles being in the quasi-liquid state and capable of coalescing and forming an alloy – solid solution – were found: Nb – 2.1÷2.2 nm, Sn – 0.4 nm, Pb – 0.6 nm, Cd – 3.2 nm. The following concentrations were determined as the boundary of a range where solid metal solutions exist in niobium, at%: Sn – 25.5, Pb – 23.0, Cd – 64.5. The solid solution is a crystal lattice of the niobium as a matrix metal comprising lead, cadmium and tin atoms. The Nb matrix lattice parameters change with additional stresses arising in it up to its destruction due to the fact that the atom sizes of embedded metals differ from those of matrix niobium. The body-centered cubic lattice parameters of solid solutions increase with the rising Pb, Cd и Sn concentrations since they have larger atomic sizes as compared to niobium. A change in the crystal lattice growth rate was observed for lead and cadmium alloys due to a change in the impurity atom arrangement in the niobium matrix lattice. The critical sizes of metal particles obtained were used to estimate surface tension parameters at the crystal/melt interface as follows: 1.17–1.22 J/m2 for Nb, 1.15·10–2 – for Sn; 1.48·10–2 – for Pb; 0.142 – for Cd. Refractory niobium alloying with tin, lead and cadmium is an example of using the size effect to produce new materials.

Polymorphism of p-450 cytochrome detoxication genes in adolescents depending on the degree of contamination of the organism by heavy metals

2020 ◽  
Vol 99 (5) ◽  
pp. 478-482
Author(s):  
N. P. Setko ◽  
A. G. Setko ◽  
Ekaterina V. Bulycheva ◽  
A. V. Tyurin ◽  
E. Yu. Kalinina
Keyword(s):  
Heavy Metals ◽  
Environmental Factors ◽  
Heavy Metal Contamination ◽  
Atomic Absorption Spectrophotometry ◽  
The Body ◽  
Lead And Cadmium ◽  
Cyp2b6 Gene ◽  
Cytochrome P 450 ◽  
Gene Cyp1a1 ◽  
Group 1

Introduction. Changes in the body of children and adolescents aimed at adapting to environmental factors are determined by genetic polymorphism in xenobiotic biotransformation genes, determining the degree of susceptibility of the child’s body to pollutants, which is the basis of modern personalized preventive medicine when managing risks to the health of the child population under the influence of environmental factors. Material and methods. Trace elements, including heavy metals, lead and cadmium, were determined in the hair of 256 practically healthy teenagers by atomic absorption spectrophotometry. Depending on the level of content of the latter, two groups of adolescents were formed to determine six genes of the cytochrome P-450 family. Group 1 consisted of adolescents whose cadmium lead content exceeded the average Russian indices. The second group included adolescents whose heavy metals were above the level of average Russian standards. Results. Studies have shown that in adolescents of the 1st group, compared with the data of adolescents of the 2nd group, an increase in the number of carriers of two mutant alleles at the locus rs 1048943 (gene CYP1A1) is 3.08 times, rs 464621 (gene CYP1A1) is 1. 8 times; locus rs 2069522 (CYP1A2 gene) 3.63 times; locus rs 1799853 (CYP2C9 * 2 gene) 4.5 times; locus rs 1057910 (gene CYP2C9 * 3) 3.8 times and locus rs 2279343 (gene CYP2B6) 4.25 times. Moreover, carriers of two normal alleles in adolescents of the first group at the locus rs 1048943 (gene CYP1A1) were 5.14 times; locus rs 2279343 (CYP2B6 gene) was 6.5 fold less than among adolescents of the 2nd group; and at the locus rs 464621 (gene CYP1A1), rs 2069522 (gene CYP1A2), rs 1799853 (gene CYP2C9 * 2), rs 1057910 (gene CYP2C9 * 3) there were no carriers of normal homozygotes. Conclusion. Group 1 adolescents with heavy metal contamination of the body are carriers significantly in a greater number of pathological mutations in the genes of the cytochrome P-450 detoxification system in comparison with data from group 2 adolescents.

Determination of Some Heavy Metals in Milk of Cow Grazing At Selected Areas, of Kaduna Metropolis

2017 ◽  
Vol 7 (7) ◽  
pp. 341 ◽  
Author(s):  
Mahmud Mohammed Imam ◽  
Zahra Muhammad ◽  
Amina Zakari
Keyword(s):  
Heavy Metals ◽  
Cadmium Toxicity ◽  
Research Work ◽  
The Body ◽  
Cow Milk ◽  
Scientific Model ◽  
Potential Health ◽  
Milk Samples ◽  
Lead And Cadmium ◽  
Digestion Technique

In this research work the concentration of zinc, copper, lead, chromium, cadmium, and nickel in cow milk samples obtained from four different grazing areas   (kakuri, kudendan, malali, kawo) of Kaduna metropolis. The samples were digested by wet digestion technique .The trace element were determined using bulk scientific model VPG 210 model  Atomic Absorption Spectrophotometer (AAS).. The concentration of the determined heavy metal were The result revealed that Cr,  Ni and Cd were not detected in milk samples from Kawo, Malali  and Kudendan whereas lead (Pb) is detected in all samples and found to be above  the stipulated limits of recommended dietary allowance (NRC,1989) given as 0.02mg/day. Cu and Zn are essential elements needed by the body for proper metabolism and as such their deficiency or excess is very dangerous for human health. However, they were found in all samples and are within the recommended limits while Cd (2.13 – 3.15 mg/kg) in milk samples from Kakuri was found to be above such limit (0.5mg/day). Cow milk samples analyzed for heavy metals in this research work pose a threat of lead and cadmium toxicity due to their exposure to direct sources of air, water and plants in these grazing areas, thereby, resulting to a potential health risk to the consumers.

Liquid State Polydimethylsiloxane (PDMS) Wrinkle Formation Process for Various Applications.

2010 ◽  
Vol 1272 ◽  
Author(s):  
Sang Hoon Lee ◽  
Jangbae Jeon ◽  
Sang Ho Lee ◽  
Moon J. Kim
Keyword(s):  
Thin Film ◽  
Formation Process ◽  
Liquid State ◽  
Metal Particles ◽  
Film Electrode ◽  
Biological Applications ◽  
Vacuum Plasma ◽  
Vacuum States ◽  
Flexible Metal ◽  
Deposition Conditions

AbstractHere we report an epoch-making simple fabrication for wrinkle formation. The present wrinkle formation process is a solution for controlling the area, shape and direction of wrinkle area by forming wrinkles on the liquid state polydimethylsiloxane directly exposed to sputtered metal particles in the low vacuum plasma chamber in various vacuum states and deposition conditions. Also the process allows us to make extremely flexible metal thin film electrode with approved adhesion. These bring us possibilities of actual electrical and biological applications.

Superstructure formation in the solid solution Sc3Pt3−xIn3 (x = 0–0.93)

2021 ◽  
Vol 0 (0) ◽  
Author(s):  
Nataliya L. Gulay ◽  
Rolf-Dieter Hoffmann ◽  
Jutta Kösters ◽  
Yaroslav M. Kalychak ◽  
Stefan Seidel ◽  
...  
Keyword(s):  
Solid Solution ◽  
Diffraction Data ◽  
High Frequency ◽  
Lattice Parameters ◽  
X Ray Diffraction ◽  
Space Group ◽  
X Ray ◽  
Platinum Content ◽  
Arc Melting ◽  
Modulation Vector

Abstract The equiatomic indide ScPtIn (ZrNiAl type, space group P 6 ‾ $‾{6}$ 2m) shows an extended solid solution Sc3Pt3–xIn3. Several samples of the Sc3Pt3–xIn3 series were synthesized from the elements by arc-melting and subsequent annealing, or directly in a high frequency furnace. The lowest platinum content was observed for Sc3Pt2.072(3)In3. All samples were characterized by powder X-ray diffraction and their lattice parameters and several single crystals were studied on the basis of precise single crystal X-ray diffractometer data. The correct platinum occupancy parameters were refined from the diffraction data. Decreasing platinum content leads to decreasing a and c lattice parameters. Satellite reflections were observed for the Sc3Pt3–xIn3 crystals with x = 0.31–0.83. These satellite reflections could be described with a modulation vector ( 1 3 , 1 3 , γ ) $\left(\frac{1}{3},\frac{1}{3},\gamma \right)$ ( γ = 1 2 $\gamma =\frac{1}{2}$ c* for all crystals) and are compatible with trigonal symmetry. The interplay of platinum filled vs. empty In6 trigonal prisms is discussed for an approximant structure with space group P3m1.

scholarly journals Monitoring the effects of exposure to lead and cadmium in working and living environment through standard biochemical blood parameters and liver endonucleases activity

2011 ◽  
Vol 65 (4) ◽  
pp. 403-409 ◽  
Author(s):  
Ruzica Nikolic ◽  
Jasmina Jovanovic ◽  
Gordana Kocic ◽  
Tatjana Cvetkovic ◽  
Svetlana Stojanovic ◽  
...  
Keyword(s):  
Liver Enzymes ◽  
Harmful Effect ◽  
Toxic Metal ◽  
Combustion Products ◽  
Blood Parameters ◽  
Living Environment ◽  
The Body ◽  
Lead Contamination ◽  
Lead And Cadmium ◽  
High Level

Heavy metals as pollutants in the working and living environment are a serious health and environmental problem because they are toxic, non-biodegradable, accumulate in living systems and have a long half-life in soil. Sources of lead contamination are combustion products in the chemical industry and metallurgy, industrial waste water, landfills, traffic etc. Lead enters into the body via the food chain and drinking water. In the body lead is deposited in the liver, kidneys, brain and mineral tissues. Excretion of lead causes damage to the epithelial cells of certain organs. High level exposure to cadmium is usually the result of environmental pollution by human activities. Exposure to cadmium can lead to acute and chronic tissue damage of various organs, including liver and kidneys in humans and in animals. In this paper we analyzed the effects of lead and cadmium exposure, in working and living environment, on the model system of experimental animals, particularly the activity of certain liver enzymes, acid and alkaline DNase, and standard biochemical blood parameters. The study showed that lead and cadmium significantly affect the protein content, red blood cells, hemoglobin and hematocrit, and the activity of liver enzymes. This harmful effect of this toxic metal can be reduced by the supplements.

scholarly journals Magnetically Oriented Powder Crystal to Indexing and Structure Determination

2014 ◽  
Vol 70 (a1) ◽  
pp. C1560-C1560
Author(s):  
Fumiko Kimura ◽  
Wataru Oshima ◽  
Hiroko Matsumoto ◽  
Hidehiro Uekusa ◽  
Kazuaki Aburaya ◽  
...  
Keyword(s):  
Crystal Structure ◽  
Single Crystal ◽  
Crystal Lattice ◽  
Powder Diffraction ◽  
Diffraction Method ◽  
Lattice Parameters ◽  
X Ray Diffraction ◽  
X Ray ◽  
Crystal Lattice Parameters

In pharmaceutical sciences, the crystal structure is of primary importance because it influences drug efficacy. Due to difficulties of growing a large single crystal suitable for the single crystal X-ray diffraction analysis, powder diffraction method is widely used. In powder method, two-dimensional diffraction information is projected onto one dimension, which impairs the accuracy of the resulting crystal structure. To overcome this problem, we recently proposed a novel method of fabricating a magnetically oriented microcrystal array (MOMA), a composite in which microcrystals are aligned three-dimensionally in a polymer matrix. The X-ray diffraction of the MOMA is equivalent to that of the corresponding large single crystal, enabling the determination of the crystal lattice parameters and crystal structure of the embedded microcrytals.[1-3] Because we make use of the diamagnetic anisotropy of crystal, those crystals that exhibit small magnetic anisotropy do not take sufficient three-dimensional alignment. However, even for these crystals that only align uniaxially, the determination of the crystal lattice parameters can be easily made compared with the determination by powder diffraction pattern. Once these parameters are determined, crystal structure can be determined by X-ray powder diffraction method. In this paper, we demonstrate possibility of the MOMA method to assist the structure analysis through X-ray powder and single crystal diffraction methods. We applied the MOMA method to various microcrystalline powders including L-alanine, 1,3,5-triphenyl benzene, and cellobiose. The obtained MOMAs exhibited well-resolved diffraction spots, and we succeeded in determination of the crystal lattice parameters and crystal structure analysis.

scholarly journals The Effect of High-Intensity Electron Beam on the Crystal Structure, Phase Composition, and Properties of Al–Si Alloys with Different Silicon Content

2021 ◽  
Vol 22 (1) ◽  
pp. 129-157
Author(s):  
D. V. Zaguliaev ◽  
S. V. Konovalov ◽  
Yu. F. Ivanov ◽  
V. E. Gromov ◽  
V. V. Shlyarov ◽  
...  
Keyword(s):  
Solid Solution ◽  
Electron Beam ◽  
Phase Composition ◽  
Crystal Lattice ◽  
High Intensity ◽  
Materials Science ◽  
Lattice Parameter ◽  
Crystal Lattice Parameter ◽  
Material Surface ◽  
Modified Layer

The study deals with the element–phase composition, microstructure evolution, crystal-lattice parameter, and microdistortions as well as the size of the coherent scattering region in the Al–10.65Si–2.11Cu and Al–5.39Si–1.33Cu alloys irradiated with the high-intensity electron beam. As revealed by the methods of x-ray phase analysis, the principal phases in untreated alloys are the aluminium-based solid solution, silicon, intermetallics, and Fe2Al9Si2 phase. In addition, the Cu9Al4 phase is detected in Al–10.65Si–2.11Cu alloy. Processing alloys with the pulsed electron beam induces the transformation of lattice parameters of Al–10.65Si–2.11Cu (aluminium-based solid solution) and Al–5.39Si–1.33Cu (Al1 and Al2 phases). The reason for the crystal-lattice parameter change in the Al–10.65Si–2.11Cu and Al–5.39Si–1.33Cu alloys is suggested to be the changing concentration of alloying elements in the solid solution of these phases. As established, if a density of electron beam is of 30 and 50 J/cm2, the silicon and intermetallic compounds dissolve in the modified layer. The state-of-the-art methods of the physical materials science made possible to establish the formation of a layer with a nanocrystalline structure of the cell-type crystallization because of the material surface irradiation. The thickness of a modified layer depends on the parameters of the electron-beam treatment and reaches maximum of 90 µm at the energy density of 50 J/cm2. According to the transmission (TEM) and scanning (SEM) electron microscopy data, the silicon particles occupy the cell boundaries. Such changes in the structural and phase states of the materials response on their mechanical characteristics. To characterize the surface properties, the microhardness, wear parameter, and friction coefficient values are determined directly on the irradiated surface for all modification variants. As shown, the irradiation of the material surface with an intensive electron beam increases wear resistance and microhardness of the Al–10.65Si–2.11Cu and Al–5.39Si–1.33Cu alloys.

scholarly journals Use of water-alcohols treatment of medicinal plants under conditions modeling intoxication by lead and cadmium

2021 ◽  
pp. 80-88
Author(s):  
Yu. I. Koval ◽  
T. I. Bokova ◽  
A. F. Petrov
Keyword(s):  
Heavy Metals ◽  
Medicinal Plants ◽  
Blood Serum ◽  
Raw Materials ◽  
Antioxidant Properties ◽  
Live Weight ◽  
The Body ◽  
Laboratory Animals ◽  
Lead And Cadmium ◽  
Water Alcohol

The results of studying the effects of water-alcohol infusions of medicinal plants - rhizomes of thick-leafed incense (Bergenia crasslifolia L. Fritsch), dioica nettle leaves (Urtica dioca L.), burdock roots (Arctium lappa L.), and mother-and-leaf leaves - are presented. ordinary machichi (Tussilago farfara L.) on the organism of laboratory rats under conditions of short-term intoxication with heavy metals in doses of 25 mg of lead and 2.5 mg of cadmium per 1 kg of live weight. In the course of studies it was found that the effect of heavy metals on the body of laboratory animals is selective - the main “depot” of lead was bone tissue, and cadmium - the kidneys and liver. The addition of 1 ml of water-alcohol infusions from medicinal raw materials to the diet of rats as detoxicants caused a decrease in the level of lead in the animal organism to 6.32 times, cadmium to 3.46 times. The greatest detoxification ability was shown by infusions of the roots of burdock and leaves of nettle dioecious. Under the influence of elevated doses of lead and cadmium in laboratory animals there was an increase in heart mass by 40.34 % and spleen by 89.91 %, a decrease in the content of alkaline phosphatase in blood serum by 25.81 %. Water-alcohol infusions normalized the biochemical parameters of rat blood serum. Studies have shown that the infusions of rhizomes of thick-leafed frangipani, burdock roots, dioecious nettles and coltsfoot leaves with antioxidant properties can be the basis for the development of an effective herbal preparation used for the prevention and treatment of animals from intoxication with salts of heavy metals.

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