Research organic light-emitting diodes with colloidal quantum dots

In this research we have created light-emitting structures that contain colloidal quantum dots of cadmium selenide in the active layer. To do so, we have used the method of vacuum thermal deposition for the formation of organic layers. This method allowed us to create several OLED structures. We have compared their photo- and electroluminescence spectra, and have revealed necessary conditions for the creation of high quality layers

Acute kidney injury as a consequence of the use of anesthesia during surgery: causes and approaches to reducing the risk of

The article reveals the causes and approaches to reducing the risk of acute kidney injury that occurs as a result of surgical intervention. The authors note that this problem is extremely urgent, since the effect of anesthesia on acute kidney injury may depend on various factors, including the type of anesthesia, the duration of surgery, the patient’s condition and the anesthetics used. Some anesthetics and agents used during general anesthesia can cause hypotension (lowering of blood pressure). This can lead to a decrease in blood flow in the kidneys and deterioration of their function. It is important to keep blood pressure at an optimal level during surgery to minimize the risk of kidney damage. Patients with pre-existing kidney problems may be more susceptible to the negative effects of anesthesia. The anesthesiologist should assess the condition of the kidneys before surgery and choose the anesthetics and methods that are least likely to cause additional damage. The effect of anesthesia on acute kidney injury can be complex and depends on many factors. It is important that the anesthesiologist and the surgeon work together to minimize risks to the kidneys and ensure safe operation in patients with acute kidney injury

In Situ Spectral Magnetoellipsometry for Structural, Magnetic and Optical Properties of Me/Si (Me Mn, Fe) Nanolayers

In our work we present in-situ spectral magnetoellipsometer is equipped with sapphire manipulator. which allows us to carry out in-situ and in-time optical and magnetooptical measurements in the range from 10 K to 1500 K in spectral range 1.5 eV-4.0 eV (830 nm-300 nm), the range of magnetic fields is +/-0.4 T. When you are citing the document, use the following link http://essuir.sumdu.edu.ua/handle/123456789/3555

Fractional conservation laws in optimal control theory

Using the recent formulation of Noether's theorem for the problems of the calculus of variations with fractional derivatives, the Lagrange multiplier technique, and the fractional Euler-Lagrange equations, we prove a Noether-like theorem to the more general context of the fractional optimal control. As a corollary, it follows that in the fractional case the autonomous Hamiltonian does not define anymore a conservation law. Instead, it is proved that the fractional conservation law adds to the Hamiltonian a new term which depends on the fractional-order of differentiation, the generalized momentum, and the fractional derivative of the state variable.Comment: The original publication is available at http://www.springerlink.com Nonlinear Dynamic

Quasi freestanding graphene on SiC 0001 via cobalt intercalation of zero layer graphene

Modification of the electronic and crystal structure of zero layer graphene grown on 6H SiC 0001 after Co intercalation is reported. Using a wide range of techniques including angle resolved photoelectron spectroscopy, x ray photoelectron spectroscopy, Raman spectroscopy, low energy electron diffraction, we found that zero layer graphene on SiC transforms into graphene monolayer as a result of cobalt intercalation. The Dirac cone of amp; 960; band characteristic of quasi freestanding graphene is observed. In combination with high resolution transmission electron microscopy and atomic force microscopy data, we conclude that ultrathin silicide CoSi CoSi2 structure is formed between graphene and SiC substrate. Investigation of magnetic properties reveals ferromagnetic behavior with open hysteresis loop. The results of this work are the basis for further implementation of magneto spin orbit graphene on a semiconducting substrate and are important for the future application of such graphene in spintronic

Luminescence of nanostructures based on semiconductor nitrides

Light-emitting diode structures on the basis of (Al, Ga, ln)N solid solutions with and without superlattices were investigated. Experiments in a wide range of temperatures (10—300 K) and noise currents (10 nA — 2 mA) were performed. It was found that the structure with superlattices has a higher stability and better work performance. Apparently, the use of superlattices can compensate for the elastic stresses and piezoelectric fields at the heterointerface. This compensation reduces the formation of dislocations in the structures with superlattices, which increases the intensity of radiation and decreases self-heating effects