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1.
Nanomaterials (Basel) ; 12(24)2022 Dec 19.
Article in English | MEDLINE | ID: mdl-36558348

ABSTRACT

The paper considers the new effects of the nanoscale state of matter, which open up prospects for the development of electronic devices using new physical principles. The contacts of chemically homogeneous nanoparticles of yttrium-stabilized zirconium oxide (ZrO2­x mol% Y2O3, x = 0, 3, 4, 8; YSZ) with different sizes of 7.5 nm and 9 nm; 7.5 nm and 11 nm; and 7.5 nm and 14 nm, respectively, was studied on direct current using nanostructured objects in the form of compacts obtained by high-hydrostatic pressure (HP-compacts of 300MPa). A unique size effect of the nonlinear (rectifying-type contact) dependence of the electrical properties (in the region U < 2.5 V, I ≤ 2.7 mA) of the contact of different-sized YSZ nanoparticles of the same chemical composition is revealed, which indicates the possibility of creating semiconductor structures of a new type (homogeneous electronics). The electronic structure of the near-surface regions of nanoparticles of studied oxide materials and the possibility of obtaining specifically rectifying properties of the contacts were studied theoretically. Models of surface states of the Tamm-type are constructed considering the Coulomb long-range action. The discovered energy variance and its dependence on the curvature of the surface of nanoparticles made it possible to study the conditions for the formation of a contact potential difference in cases of nanoparticles of the same radius (synergistic effect), different radii (doped and undoped variants), as well as to discover the possibility of describing a group of powder particles within the Anderson model. The determined effect makes it possible to solve the problem of diffusion instability of semiconductor heterojunctions and opens up prospects for creating electronic devices with a fundamentally new level of properties for use in various fields of the economy and breakthrough critical technologies.

2.
Nanomaterials (Basel) ; 12(11)2022 May 24.
Article in English | MEDLINE | ID: mdl-35683639

ABSTRACT

The dimensional effect of electric charge storage with a density of up to 270 µF/g by the hydrated ZrO2-nanoparticles system was determined. It was found that the place of localization of different charge carriers is the generalized heterophase boundary-nanoparticles surface. The supposed mechanism of the effect was investigated using the theory of dispersed systems, the band theory, and the theory of contact phenomena in semiconductors, which consists of the formation of localized electronic states in the nanoparticle material due to donor-acceptor interaction with the adsorption ionic atmosphere. The effect is relevant for modern nanoelectronics, microsystem technology, and printed electronics because it allows overcoming the basic physical restrictions on the size, temperature, and operation frequency of the device, caused by leakage currents.

3.
J Psychiatr Res ; 148: 258-263, 2022 04.
Article in English | MEDLINE | ID: mdl-35151217

ABSTRACT

In the present study we measured the concentrations of cortisol, thyroid hormones, testosterone, and GABA (gamma aminobutyric acid) in am blood plasma samples of combatants with an at least 10 year history of military psychological trauma (N = 74) divided in groups that either suffer from post-traumatic stress disorder (PTSD) (N = 37) or are resistant (N = 37) as well as in a control group without traumatic experience in the anamnesis, (N = 34). PTSD symptoms were assessed using the Clinician-Administered PTSD Scale (CAPS). The results show that the am blood cortisol levels of individuals that were exposed to war zone experiences irrespective susceptibility for or resistance to PTSD were significantly higher than the values observed in the controls. Testosterone levels in PTSD patients differed neither from that observed in PTSD resistant nor control groups. In the resistant group testosterone levels were however significantly higher than in controls. The level of all thyroid hormones did not differ between the study groups. GABA level was significantly lower in the PTSD group compared with healthy controls. In the resistant group blood GABA levels were not significantly different from either PTSD patients or controls. In conclusion, the current data show that cortisol and to some extent testosterone may serve as biomarker of war zone stress per se, even if trauma was experienced at least ten years before, rather than of only PTSD or resistance to PTSD. GABA, in contrast, can be considered a potential marker of the protracted nature of PTSD.


Subject(s)
Stress Disorders, Post-Traumatic , Veterans , Biomarkers , Disease Susceptibility , Humans , Hydrocortisone , Stress Disorders, Post-Traumatic/diagnosis , Testosterone , Thyroid Hormones , Veterans/psychology , gamma-Aminobutyric Acid
4.
Integr Zool ; 1(2): 70-2, 2006 Jun.
Article in English | MEDLINE | ID: mdl-21395995

ABSTRACT

Food additives made of placenta tissues of healthy cattle, included in the diet of cows 23-38 days before calving and/or in different intervals of the postpartum period, stimulated the resumption of ovary activity and the manifestation of normal estrus cycles (with ovulation) in cows. The cow fertilization rates during 80 days after calving was 50-80%. These values increased more than twofold in comparison with the fertility level of cows fed a normal diet. The level of fertilization after inclusion of placenta-containing additives in the diet of cows 5 days before ovulation, in estrus cycles that took place during 6 months after calving, increased 38 % on average, in comparison with that of cows fed a normal diet.

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