Role of active surface in processes of hydrogen sorption-desorption by intermetallic compounds

1993 ◽  
Vol 18 (6) ◽  
pp. 505-510
Author(s):  
R IBRASHEVA ◽  
T SOLOMINA ◽  
G LEONOVA ◽  
V MORDOVIN ◽  
A BEKTUROV
2018 ◽  
Vol 69 (10) ◽  
pp. 2826-2832
Author(s):  
Ioan Gabriel Sandu ◽  
Viorica Vasilache ◽  
Andrei Victor Sandu ◽  
Marin Chirazi ◽  
Cezar Honceriu ◽  
...  

The saline aerosols generated in gaseous media, as nanodispersions, behave, with respect to the concentration levels and the lifespan, as trimodal distributions (the three domains with Gaussian distributions: fine or Aitken under 50 �m, medium between 50 and 500 mm and, respectively, coarse or large between 500 and 1000 mm). The generation in latent state is dependent on the active surface of the source (number of generator centres, the size and position of the fluorescences, the porosity, size and shape of the source, etc.), the climatic parameters, but also on a series of other characteristics of the gaseous medium. Our team has demonstrated experimentally that saline aerosols, NaCl type, besides the ability to prevent and treat broncho-respiratory and cardiac conditions, through coassistance of saline aerosols of other cations than sodium, and of the iodine anion, have for certain levels of concentrations propitious effects over the immune, bone and muscular systems. Similarly proved has been the positive influence on the development of children, as well the determinant role in increasing athletic performance and of other human subjects performing intense activities.


1992 ◽  
Vol 32 (5) ◽  
pp. 680-686 ◽  
Author(s):  
I. E. Nemirovskaya ◽  
A. N. Grechenko ◽  
A. M. Alekseev ◽  
V. V. Lunin

2021 ◽  
Vol 12 ◽  
Author(s):  
Hitesh Kumar Dewangan

: Poor solubility of some medicinal compounds is a serious challenge that can be addressed by using a nano-suspension for improved delivery. The nanoparticles enhance the bioavailability along with the aqueous solubility of the drug, which is accomplished by increasing the active surface area of the drug. The gained attention of the nanosuspension is due to its stabilization facility, which is achieved by polymers, such as polyethylene glycol (PEG), having a particular size range of 10 - 100 nm. Hence, these nanoparticles have the capacity of binding to the targeted with very low damage to the healthy tissues. These are prepared by various methods, such as milling, high-pressure homogenization, and emulsification, along with melt emulsification. Moreover, surface modification and solidification have been used to add specific properties to the advanced therapies as post-processing techniques. For many decades, it has been known that water solubility hampers the bioavailability and not all drugs are water-soluble. In order to combat this obstacle, nanotechnology has been found to be of specific interest. For elevating the bioavailability by increasing the dissolution rate, the methodology of reduction of the associated drug particles into their subsequent submicron range is incorporated. For oral and non-oral administration, these nanosuspension formulations are used for the delivery of drugs.


2007 ◽  
Vol 560 ◽  
pp. 97-102 ◽  
Author(s):  
Felipe García ◽  
Armando Salinas-Rodríguez ◽  
Enrique Nava-Vázquez

The reaction between solid steel and liquid Al-Zn-Si alloy leads to the formation of a solid intermetallic interfacial layer. In the case of industrial Al-43.5Zn-1.5Si coated steel strips, the thickness of the intermetallic layer is on average 1.35 μm and the kinetics of the reaction is controlled by the effect of Si on Al and Fe diffusivities through the solid intermetallic layer. In this paper it is shown that the thickness of the intermetallic interfacial layer decreases as the Si content in the liquid alloy increases. EDXS microanalysis at the interface of industrial coated steel strips shows that the interfacial intermetallic compounds are chemically similar to those formed in the bulk of Al-43.5Zn-1.5Si liquid baths in continuous coating lines. Differential acid dissolution of the coatings reveals that the intermetallic layer is not planar at the interface with the coating overlay and is formed by grains of different size and chemical composition. Addition of minute quantities of Ti to the Al-Zn-Si liquid alloy causes changes in the morphology of the intermetallic layer and an overall refining of the microstructure.


1988 ◽  
Vol 3 (3) ◽  
pp. 426-440 ◽  
Author(s):  
Osamu Izumi ◽  
Takayuki Takasugi

The present article first describes some characteristics of structure, chemistry, and electronic (bond) nature for grain boundaries in the A3B Li2-type intermetallic compounds. Next, the phenomenological aspects for the grain boundary brittleness of the Li2-type intermetallic compounds are reviewed with respect to the combination of the constituent atoms, the alloying effect, the stoichiometry effect, and a role of impurity or gaseous atoms. It is emphasized that the brittleness of grain boundaries in the intermetallic compounds is directly controlled by the atomistic and electronic structures at grain boundary regions. Based on these systematic investigations, it is suggested that the brittleness of the Li2-type intermetallic compounds can be manipulated by appropriate control of composition and the corresponding electrochemical bond environment at grain boundary planes and by control of test environment. Furthermore, some examples of the materials development are described.


2016 ◽  
Vol 1 (2) ◽  
pp. 7-11
Author(s):  
Мельникова ◽  
Natalya Melnikova ◽  
Нечаева ◽  
Elena Nechaeva ◽  
Редин ◽  
...  

The purpose is to justify the use of minimum and zero tillage in conditions of forest-steppe Zavolzhye region from the position of the biological activity of the soil. One of the factors forming and determining the fertility of the soil, is the activity of microorganisms that inhabit it, the active surface which reaches up to several hundred acres for 1 ha of surface topsoil. Important role in building of soil fertility is the number of major groups of microorganisms, which, being the catalysts of metabolism, objectively reflect the nature of biochemical processes. Another academician S. P. Kostychev (1937) pointed out that without the study of biodynamics the knowledge of the soil, especially from the agronomic point of view, may not be complete. Microorganisms occupy a key position in maintaining biochemical capacity of the soil, so monitoring of soil microflora is essential for the maintenance and reproduction of its fertility. This work is devoted to studying the role of soil microorganisms in the process of maintaining and reproduction of soil fertility in the development of new technologies in agriculture. The article presents data on the effect of basic tillage on the number of different groups of soil microorganisms (micromycetes, bacteria, actinomycetes), Shows the number of soil microorganisms, such as micromycetes (mold fungi) and bacteria are significantly influenced by seasonal changes in temperature and humidity than the soil treatment methods. From which it follows that the reduction of the mechanical load on the soil in the forest-steppe of Zavolzhye a significant impact on the number of major groups of microorganisms has not.


2006 ◽  
Vol 89 (20) ◽  
pp. 201909 ◽  
Author(s):  
I. Jacob ◽  
M. Bereznitsky ◽  
O. Yeheskel ◽  
R. G. Leisure

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