271 research outputs found
Evaluation of Contemporary Environmental Condition of River Basins in Southern Pre-Caspian Areas of Azerbaijan
Southern Pre-Caspian areas of the Republic of Azerbaijan have favorable geographical position as well as
natural and climatic condition for dwelling, development of settlements, and industrial activity. Most areas have
fertile soils and attractive landscapes. These factors facilitate human distribution in the researched area and
therefore, the area is highly populated. Population are engaged mainly in areas such as farming, namely
production of tea, vine, cereals, vegetable, different fruits, including citrus plants, production of foods, and also
cattle- and sheep-breeding. As a result, the coastal zone and rivers experience high anthropogenic influence.
This article deals with the study of anthropogenic pollution of highly-settled river basins and valleys as well as
evaluation of changes going by quality of river waters in southern Pre-Caspian areas of Azerbaijan
Influence of dispersing additive on asphaltenes aggregation in model system
The work is devoted to investigation of the dispersing additive influence on asphaltenes aggregation in the asphaltenes-toluene-heptane model system by photon correlation spectroscopy method. The experimental relationship between the onset point of asphaltenes and their concentration in toluene has been obtained. The influence of model system composition on asphaltenes aggregation has been researched. The estimation of aggregative and sedimentation stability of asphaltenes in model system and system with addition of dispersing additive has been given
STRUCTURAL AND TECHNOLOGICAL PARAMETERS AFFECTING THE BIPOLAR STATIC INDUCTION TRANSISTOR (BSIT ) RESISTANCE
Aim. The aim of the study is to determine the impact of structural and technological parameters on the resistance of the bipolar static induction transistor.Methods. The paper provides aΒ comparative analysis of the advantages of bipolar static induction transistor compared to the bipolar power transistors, MOSFETs and insulated-gate bipolar transistor (IGBT). Considered are structural and technological parameters that influence the resistance of BSIT-transistor.Result. As a result of experimental study on silicon substrates were formed test prototypes of BSIT transistor structure, are presented calculation and experimental works. Obtained are the resistance dependencies of the transistor cell on the thickness of the epitaxial film; the resistance dependencies of BSIT transistor cell on the effective gate length for different values of the impurity concentration in the epitaxial film; dependencies resistance of the transistor cell on the gate length at different values of the epitaxial film thickness; the resistance dependencies of BSIT transistor cell on the distance between the mask for the p-region and the gate; dependencies on the multiplication the cell resistance by its area on the gate length.Conclusion. When increasing the gate length (Lk) and the mask length for the p-region (lp +) in the transistor structure, the resistance decreases and the dependence of multiplication of the cell resistance by its area Q on the gate length has this case the minimum
Interband electron Raman scattering in a quantum wire in a transverse magnetic field
Electron Raman scattering (ERS) is investigated in a parabolic semiconductor
quantum wire in a transverse magnetic field neglecting by phonon-assisted
transitions. The ERS cross-section is calculated as a function of a frequency
shift and magnetic field. The process involves an interband electronic
transition and an intraband transition between quantized subbands. We analyze
the differential cross-section for different scattering configurations. We
study selection rules for the processes. Some singularities in the Raman
spectra are found and interpreted. The scattering spectrum shows
density-of-states peaks and interband matrix elements maximums and a strong
resonance when scattered frequency equals to the "hybrid" frequency or
confinement frequency depending on the light polarization. Numerical results
are presented for a GaAs/AlGaAs quantum wire.Comment: 8 pages, 5 figure
ΠΡΠΈΠΌΠ΅Π½Π΅Π½ΠΈΠ΅ ΡΠΊΡΡΡΠ°ΠΊΠΎΡΠΏΠΎΡΠ°Π»ΡΠ½ΡΡ ΡΠΈΡΡΠ΅ΠΌ ΠΏΡΠΎΡΠ΅Π·ΠΈΡΠΎΠ²Π°Π½ΠΈΡ ΡΡΠ½ΠΊΡΠΈΠΉ ΠΏΠ΅ΡΠ΅Π½ΠΈ ΠΏΡΠΈ ΠΎΡΡΡΠΎΠΉ Π΄Π΅ΠΊΠΎΠΌΠΏΠ΅Π½ΡΠΈΡΠΎΠ²Π°Π½Π½ΠΎΠΉ ΠΏΠ΅ΡΠ΅Π½ΠΎΡΠ½ΠΎΠΉ Π½Π΅Π΄ΠΎΡΡΠ°ΡΠΎΡΠ½ΠΎΡΡΠΈ
The aim of the study: to evaluate the eο¬cacy of extracorporeal liver support systems in patients with acute liver failure of various etiologies.Material and methods. The study included 117 patients with acute liver failure of various etiologies. The main group consisted of 71 patients who received complex intensive therapy, including MARS-therapy and hemodiaο¬ltration. The comparison group included 46 patients who received albumin dialysis (24 patients) and hemodiaο¬ltration (22 patients) alone. The mean age of the patients was 34Β±5.6 years, the majority (56.4%) were men. Dynamic assessment of patients' severity was performed using Sequential Organ Failure Assessment (SOFA) and Model for End-Stage Liver Disease (MELD) scales.Results. A more signiο¬cant reduction of SOFA and MELD scores was noted as early as by day 10 of intensive therapy in the main group with sequential use of extracorporeal liver detoxiο¬cation methods β to 2.7Β±0.2 vs. 8.3Β±0.5 points (P=0.021) on SOFA and to 16.7Β±0.4 vs. 23.4Β±1.4 points (P=0.023) MELD scales. The use of a comprehensive approach to extracorporeal detoxiο¬cation in acute decompensated liver failure increased the regression rate of multiple organ failure from 51.2 to 74.6% and reduced mortality from 47.8 to 25.4% (Ο2=6.266; df=1; P=0.013). At the same time, the cumulative proportion of survivors depending on the type of complication within 30 days was 88.4% in the main group and 69.0% in the comparison group (Ο2=4.164; df=1; P=0.042).Conclusion. A comprehensive approach to extracorporeal detoxiο¬cation is highly eο¬ective, providing a more signiο¬cant reduction of SOFA and MELD scores, increasing the proportion of regression of multiple organ dysfunction and reducing mortality.Π¦Π΅Π»Ρ ΠΈΡΡΠ»Π΅Π΄ΠΎΠ²Π°Π½ΠΈΡ: Π²ΡΡΠ²ΠΈΡΡ ΡΡΡΠ΅ΠΊΡΠΈΠ²Π½ΠΎΡΡΡ ΡΠΈΡΡΠ΅ΠΌ ΡΠΊΡΡΡΠ°ΠΊΠΎΡΠΏΠΎΡΠ°Π»ΡΠ½ΠΎΠΉ ΠΏΠΎΠ΄Π΄Π΅ΡΠΆΠΊΠΈ ΠΏΠ΅ΡΠ΅Π½ΠΈ Ρ ΠΏΠ°ΡΠΈΠ΅Π½ΡΠΎΠ² Ρ ΠΎΡΡΡΠΎΠΉ ΠΏΠ΅ΡΠ΅Π½ΠΎΡΠ½ΠΎΠΉ Π½Π΅Π΄ΠΎΡΡΠ°ΡΠΎΡΠ½ΠΎΡΡΡΡ ΡΠ°Π·Π»ΠΈΡΠ½ΠΎΠ³ΠΎ Π³Π΅Π½Π΅Π·Π°.ΠΠ°ΡΠ΅ΡΠΈΠ°Π» ΠΈ ΠΌΠ΅ΡΠΎΠ΄Ρ. Π ΠΈΡΡΠ»Π΅Π΄ΠΎΠ²Π°Π½ΠΈΠ΅ Π²ΠΊΠ»ΡΡΠΈΠ»ΠΈ 117 ΠΏΠ°ΡΠΈΠ΅Π½ΡΠΎΠ² Ρ ΠΎΡΡΡΠΎΠΉ ΠΏΠ΅ΡΠ΅Π½ΠΎΡΠ½ΠΎΠΉ Π½Π΅Π΄ΠΎΡΡΠ°ΡΠΎΡΠ½ΠΎΡΡΡΡ ΡΠ°Π·Π»ΠΈΡΠ½ΠΎΠ³ΠΎ Π³Π΅Π½Π΅Π·Π°. ΠΡΠ½ΠΎΠ²Π½ΡΡ Π³ΡΡΠΏΠΏΡ ΡΠΎΡΡΠ°Π²ΠΈΠ»ΠΈ 71 ΠΏΠ°ΡΠΈΠ΅Π½Ρ, ΠΊΠΎΡΠΎΡΡΠ΅ ΠΏΠΎΠ»ΡΡΠ°Π»ΠΈ ΠΊΠΎΠΌΠΏΠ»Π΅ΠΊΡΠ½ΡΡ ΠΈΠ½ΡΠ΅Π½ΡΠΈΠ²Π½ΡΡ ΡΠ΅ΡΠ°ΠΏΠΈΡ, Π²ΠΊΠ»ΡΡΠ°Ρ ΠΏΡΠΈΠΌΠ΅Π½Π΅Π½ΠΈΠ΅ MARS-ΡΠ΅ΡΠ°ΠΏΠΈΠΈ ΠΈ Π³Π΅ΠΌΠΎΠ΄ΠΈΠ°ΡΠΈΠ»ΡΡΡΠ°ΡΠΈΡ. Π Π³ΡΡΠΏΠΏΡ ΡΡΠ°Π²Π½Π΅Π½ΠΈΡ Π²ΠΊΠ»ΡΡΠΈΠ»ΠΈ 46 ΠΏΠ°ΡΠΈΠ΅Π½ΡΠΎΠ², ΠΊΠΎΡΠΎΡΡΠΌ ΠΏΡΠΈΠΌΠ΅Π½Π΅Π½Ρ ΠΈΠ·ΠΎΠ»ΠΈΡΠΎΠ²Π°Π½Π½ΠΎ Π°Π»ΡΠ±ΡΠΌΠΈΠ½ΠΎΠ²ΡΠΉ Π΄ΠΈΠ°Π»ΠΈΠ· β 24 ΠΏΠ°ΡΠΈΠ΅Π½ΡΠ° ΠΈ Π³Π΅ΠΌΠΎΠ΄ΠΈΠ°ΡΠΈΠ»ΡΡΡΠ°ΡΠΈΡ β 22 ΠΏΠ°ΡΠΈΠ΅Π½ΡΠ°. Π‘ΡΠ΅Π΄Π½ΠΈΠΉ Π²ΠΎΠ·ΡΠ°ΡΡ ΠΏΠ°ΡΠΈΠ΅Π½ΡΠΎΠ² ΡΠΎΡΡΠ°Π²ΠΈΠ» 34Β±5,6 Π»Π΅Ρ, Π±ΠΎΠ»ΡΡΠΈΠ½ΡΡΠ²ΠΎ (56,4%) Π±ΡΠ»ΠΈ ΠΌΡΠΆΡΠΈΠ½Ρ. ΠΠΈΠ½Π°ΠΌΠΈΡΠ΅ΡΠΊΡΡ ΠΎΡΠ΅Π½ΠΊΡ ΡΡΠΆΠ΅ΡΡΠΈ ΡΠΎΡΡΠΎΡΠ½ΠΈΡ ΠΏΠ°ΡΠΈΠ΅Π½ΡΠΎΠ² ΠΏΡΠΎΠ²ΠΎΠ΄ΠΈΠ»ΠΈ ΠΏΠΎ ΠΎΡΠ΅Π½ΠΎΡΠ½ΡΠΌ ΡΠΊΠ°Π»Π°ΠΌ Sequential Organ Failure Assessment (SOFA) ΠΈ Model for End-Stage Liver Disease (MELD).Π Π΅Π·ΡΠ»ΡΡΠ°ΡΡ. ΠΠΎΠ»Π΅Π΅ ΡΡΡΠ΅ΡΡΠ²Π΅Π½Π½ΠΎΠ΅ ΡΠ½ΠΈΠΆΠ΅Π½ΠΈΠ΅ ΠΏΠΎΠΊΠ°Π·Π°ΡΠ΅Π»Π΅ΠΉ ΠΏΠΎ ΡΠΊΠ°Π»Π°ΠΌ SOFA ΠΈ MELD ΠΎΡΠΌΠ΅ΡΠ΅Π½ΠΎ ΡΠΆΠ΅ ΠΊ 10 ΡΡΡΠΊΠ°ΠΌ ΠΈΠ½ΡΠ΅Π½ΡΠΈΠ²Π½ΠΎΠΉ ΡΠ΅ΡΠ°ΠΏΠΈΠΈ Π² ΠΎΡΠ½ΠΎΠ²Π½ΠΎΠΉ Π³ΡΡΠΏΠΏΠ΅ ΠΏΡΠΈ ΠΏΠΎΡΠ»Π΅Π΄ΠΎΠ²Π°ΡΠ΅Π»ΡΠ½ΠΎΠΌ ΠΈΡΠΏΠΎΠ»ΡΠ·ΠΎΠ²Π°Π½ΠΈΠΈ ΠΌΠ΅ΡΠΎΠ΄ΠΎΠ² ΡΠΊΡΡΡΠ°ΠΊΠΎΡΠΏΠΎΡΠ°Π»ΡΠ½ΠΎΠΉ Π΄Π΅ΡΠΎΠΊΡΠΈΠΊΠ°ΡΠΈΠΈ ΠΏΠ΅ΡΠ΅Π½ΠΈ ΠΏΠΎ ΡΠΊΠ°Π»Π΅ SOFA β Π΄ΠΎ 2,7Β±0,2 ΠΏΡΠΎΡΠΈΠ² 8,3Β±0,5 Π±Π°Π»Π»ΠΎΠ² (p=0,021) ΠΈ MELD β Π΄ΠΎ 16,7Β±0,4 ΠΏΡΠΎΡΠΈΠ² 23,4Β±1,4 Π±Π°Π»Π»ΠΎΠ² (p=0,023). ΠΡΠΈΠΌΠ΅Π½Π΅Π½ΠΈΠ΅ ΠΊΠΎΠΌΠΏΠ»Π΅ΠΊΡΠ½ΠΎΠ³ΠΎ ΠΏΠΎΠ΄Ρ
ΠΎΠ΄Π° ΠΊ ΡΠΊΡΡΡΠ°ΠΊΠΎΡΠΏΠΎΡΠ°Π»ΡΠ½ΠΎΠΉ Π΄Π΅ΡΠΎΠΊΡΠΈΠΊΠ°ΡΠΈΠΈ ΠΏΡΠΈ ΠΎΡΡΡΠΎΠΉ Π΄Π΅ΠΊΠΎΠΌΠΏΠ΅Π½ΡΠΈΡΠΎΠ²Π°Π½Π½ΠΎΠΉ ΠΏΠ΅ΡΠ΅Π½ΠΎΡΠ½ΠΎΠΉ Π½Π΅Π΄ΠΎΡΡΠ°ΡΠΎΡΠ½ΠΎΡΡΠΈ ΠΏΠΎΠ·Π²ΠΎΠ»ΠΈΠ»ΠΎ ΡΠ²Π΅Π»ΠΈΡΠΈΡΡ Π΄ΠΎΠ»Ρ ΡΠ΅Π³ΡΠ΅ΡΡΠ° ΠΏΠΎΠ»ΠΈΠΎΡΠ³Π°Π½Π½ΠΎΠΉ Π½Π΅Π΄ΠΎΡΡΠ°ΡΠΎΡΠ½ΠΎΡΡΠΈ Ρ 51,2 Π΄ΠΎ 74,6%, ΡΠΎΠΊΡΠ°ΡΠΈΡΡ Π»Π΅ΡΠ°Π»ΡΠ½ΠΎΡΡΡ Ρ 47,8 Π΄ΠΎ 25,4% (Ο2=6,266; df=1; p=0,013). ΠΡΠΈ ΡΡΠΎΠΌ ΠΊΡΠΌΡΠ»ΡΡΠΈΠ²Π½Π°Ρ Π΄ΠΎΠ»Ρ Π²ΡΠΆΠΈΠ²ΡΠΈΡ
Π² Π·Π°Π²ΠΈΡΠΈΠΌΠΎΡΡΠΈ ΠΎΡ ΡΠΈΠΏΠ° ΠΎΡΠ»ΠΎΠΆΠ½Π΅Π½ΠΈΡ Π² ΡΡΠΎΠΊΠΈ Π΄ΠΎ 30 ΡΡΡΠΎΠΊ ΡΠΎΡΡΠ°Π²ΠΈΠ»Π° ΠΏΡΠΈ 88,4% β Π² ΠΎΡΠ½ΠΎΠ²Π½ΠΎΠΉ Π³ΡΡΠΏΠΏΠ΅ ΠΈ 69,0% β Π² Π³ΡΡΠΏΠΏΠ΅ ΡΡΠ°Π²Π½Π΅Π½ΠΈΡ (Ο2=4,164; df=1; p=0,042).ΠΠ°ΠΊΠ»ΡΡΠ΅Π½ΠΈΠ΅. ΠΠΎΠΌΠΏΠ»Π΅ΠΊΡΠ½ΡΠΉ ΠΏΠΎΠ΄Ρ
ΠΎΠ΄ ΠΊ ΡΠΊΡΡΡΠ°ΠΊΠΎΡΠΏΠΎΡΠ°Π»ΡΠ½ΠΎΠΉ Π΄Π΅ΡΠΎΠΊΡΠΈΠΊΠ°ΡΠΈΠΈ ΠΈΠΌΠ΅Π΅Ρ Π²ΡΡΠΎΠΊΡΡ ΡΡΡΠ΅ΠΊΡΠΈΠ²Π½ΠΎΡΡΡ, ΠΎΠ±Π΅ΡΠΏΠ΅ΡΠΈΠ²Π°Ρ Π±ΠΎΠ»Π΅Π΅ ΡΡΡΠ΅ΡΡΠ²Π΅Π½Π½ΠΎΠ΅ ΡΠ½ΠΈΠΆΠ΅Π½ΠΈΠ΅ Π±Π°Π»Π»ΠΎΠ² ΠΏΠΎ ΡΠΊΠ°Π»Π°ΠΌ SOFA ΠΈ MELD, ΠΏΠΎΠ·Π²ΠΎΠ»ΡΠ΅Ρ ΡΠ²Π΅Π»ΠΈΡΠΈΡΡ Π΄ΠΎΠ»Ρ ΡΠ΅Π³ΡΠ΅ΡΡΠ° ΠΏΠΎΠ»ΠΈΠΎΡΠ³Π°Π½Π½ΠΎΠΉ Π΄ΠΈΡΡΡΠ½ΠΊΡΠΈΠΈ ΠΈ ΡΠΎΠΊΡΠ°ΡΠΈΡΡ Π»Π΅ΡΠ°Π»ΡΠ½ΠΎΡΡΡ
MODELING OF THERMOELECTRIC SYSTEM FOR LOCAL THERMAL EFFECTS ON HUMAN FOREARM ZONE
In this paper we consider a model of the thermoelectric system for the thermal effect on theΒ human forearm. The model is implemented on the basis of numerical solution of differentialequations of heat conduction for bodies of complex configuration. Two-dimensional and onedimensionalΒ graphs of the temperature change in different zones of the object of exposure aregiven
The first-nucleotide binding domain of the cystic-fibrosis transmembrane conductance regulator is important for inhibition of the epithelial Na+ channel
On a factorization of second order elliptic operators and applications
We show that given a nonvanishing particular solution of the equation
(divpgrad+q)u=0 (1) the corresponding differential operator can be factorized
into a product of two first order operators. The factorization allows us to
reduce the equation (1) to a first order equation which in a two-dimensional
case is the Vekua equation of a special form. Under quite general conditions on
the coefficients p and q we obtain an algorithm which allows us to construct in
explicit form the positive formal powers (solutions of the Vekua equation
generalizing the usual powers of the variable z). This result means that under
quite general conditions one can construct an infinite system of exact
solutions of (1) explicitly, and moreover, at least when p and q are real
valued this system will be complete in ker(divpgrad+q) in the sense that any
solution of (1) in a simply connected domain can be represented as an infinite
series of obtained exact solutions which converges uniformly on any compact
subset of . Finally we give a similar factorization of the operator
(divpgrad+q) in a multidimensional case and obtain a natural generalization of
the Vekua equation which is related to second order operators in a similar way
as its two-dimensional prototype does
Investigation of conduction band structure, electron scattering mechanisms and phase transitions in indium selenide by means of transport measurements under pressure
In this work we report on Hall effect, resistivity and thermopower
measurements in n-type indium selenide at room temperature under either
hydrostatic and quasi-hydrostatic pressure. Up to 40 kbar (= 4 GPa), the
decrease of carrier concentration as the pressure increases is explained
through the existence of a subsidiary minimum in the conduction band. This
minimum shifts towards lower energies under pressure, with a pressure
coefficient of about -105 meV/GPa, and its related impurity level traps
electrons as it reaches the band gap and approaches the Fermi level. The
pressure value at which the electron trapping starts is shown to depend on the
electron concentration at ambient pressure and the dimensionality of the
electron gas. At low pressures the electron mobility increases under pressure
for both 3D and 2D electrons, the increase rate being higher for 2D electrons,
which is shown to be coherent with previous scattering mechanisms models. The
phase transition from the semiconductor layered phase to the metallic sodium
cloride phase is observed as a drop in resistivity around 105 kbar, but above
40 kbar a sharp nonreversible increase of the carrier concentration is
observed, which is attributed to the formation of donor defects as precursors
of the phase transition.Comment: 18 pages, Latex, 10 postscript figure
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