111 research outputs found
Π‘ΡΠ°ΡΠΈΡΡΠΈΡΠ΅ΡΠΊΠΎΠ΅ ΠΈΡΡΠ»Π΅Π΄ΠΎΠ²Π°Π½ΠΈΠ΅ Π°ΠΌΠ΅ΡΡΠΎΠΏΠΈΠΈ ΠΈ Π°ΡΡΠΈΠ³ΠΌΠ°ΡΠΈΠ·ΠΌΠ° Π³Π»Π°Π·Π° ΡΠ΅Π»ΠΎΠ²Π΅ΠΊΠ°
ΠΡΠΎΠ²Π΅Π΄Π΅Π½ΠΎ Π°Π½Π°Π»ΡΠ· ΡΠΎΠ·ΠΏΠΎΠ΄ΡΠ»Ρ Π²Π΅Π»ΠΈΡΠΈΠ½ Π°ΠΌΠ΅ΡΡΠΎΠΏΡΡ ΡΠ° Π°ΡΡΠΈΠ³ΠΌΠ°ΡΠΈΠ·ΠΌΡ ΠΎΡΠ΅ΠΉ Π²Π΅Π»ΠΈΠΊΠΎΡ ΠΊΡΠ»ΡΠΊΠΎΡΡΡ ΠΏΠ°ΡΡΡΠ½ΡΡΠ² ΠΎΡΡΠ°Π»ΡΠΌΠΎΠ»ΠΎΠ³ΡΡΠ½ΠΎΠ³ΠΎ ΠΊΠ°Π±ΡΠ½Π΅ΡΠ°. ΠΠΈΡΠ²Π»Π΅Π½ΠΎ Ρ
Π°ΡΠ°ΠΊΡΠ΅Ρ ΡΠΎΠ·ΠΏΠΎΠ΄ΡΠ»Ρ ΡΠΈΡ
ΠΏΠ΅ΡΠ²ΠΈΠ½Π½ΠΈΡ
Π°Π±Π΅ΡΠ°ΡΡΠΉ ΠΎΠΊΠ° Π»ΡΠ΄ΠΈΠ½ΠΈ. ΠΠΎΠΊΠ°Π·Π°Π½ΠΎ, Π² ΡΠΊΠΈΡ
Π΄ΡΠ°ΠΏΠ°Π·ΠΎΠ½Π°Ρ
Π²ΠΎΠ½ΠΈ Π·ΡΡΡΡΡΡΠ°ΡΡΡΡΡ Π½Π°ΠΉΡΠ°ΡΡΡΡΠ΅.The statistical analysis of the 930 patientβs eyes refractometry results is done. The bar charts of the ametropy and astigmatism value distributions according to eyes number are obtained. Working ranges of the economy-type ophthalmology aberrometer are specified.ΠΡΠΎΠ²Π΅Π΄Π΅Π½ ΡΡΠ°ΡΠΈΡΡΠΈΡΠ΅ΡΠΊΠΈΠΉ Π°Π½Π°Π»ΠΈΠ· ΡΠ΅Π·ΡΠ»ΡΡΠ°ΡΠΎΠ² ΡΠ΅ΡΡΠ°ΠΊΡΠΎΠΌΠ΅ΡΡΠΈΠΈ 930 Π³Π»Π°Π· ΠΏΠ°ΡΠΈΠ΅Π½ΡΠΎΠ². ΠΡΠΈΠ²Π΅Π΄Π΅Π½Ρ Π³ΠΈΡΡΠΎΠ³ΡΠ°ΠΌΠΌΡ ΡΠ°ΡΠΏΡΠ΅Π΄Π΅Π»Π΅Π½ΠΈΡ ΠΊΠΎΠ»ΠΈΡΠ΅ΡΡΠ²Π° Π³Π»Π°Π· ΠΏΠΎ Π²Π΅Π»ΠΈΡΠΈΠ½Π΅ Π°ΠΌΠ΅ΡΡΠΎΠΏΠΈΠΈ ΠΈ Π°ΡΡΠΈΠ³ΠΌΠ°ΡΠΈΠ·ΠΌΠ°. ΠΠΏΡΠ΅Π΄Π΅Π»Π΅Π½Ρ ΡΠ°Π±ΠΎΡΠΈΠ΅ Π΄ΠΈΠ°ΠΏΠ°Π·ΠΎΠ½Ρ ΠΈΠ·ΠΌΠ΅ΡΠ΅Π½ΠΈΠΉ Π°ΠΌΠ΅ΡΡΠΎΠΏΠΈΠΈ ΠΈ Π°ΡΡΠΈΠ³ΠΌΠ°ΡΠΈΠ·ΠΌΠ° Π°Π±Π΅ΡΡΠΎΠΌΠ΅ΡΡΠ°ΠΌΠΈ ΡΠΊΠΎΠ½ΠΎΠΌ-ΠΊΠ»Π°ΡΡΠ°
Validation, reproducibility and safety of trans dermal electrical stimulation in chronic pain patients and healthy volunteers
<p>Abstract</p> <p>Background</p> <p>Surrogate pain models have been extensively tested in Normal Human Volunteers (NHV). There are few studies that examined pain models in chronic pain patients. Patients are likely to have altered pain mechanisms. It is of interest to test patient pain responses to selective pain stimuli under controlled laboratory conditions.</p> <p>Methods</p> <p>The Institutional Ethic Committee approved the study. 16 patients with chronic neuropathic radiculopathy and 16 healthy volunteers were enrolled to the study after obtaining informed consent. During electrical stimulation (150 minutes for volunteers and 75 minutes for patients) the following parameters were measured every 10 minutes:</p> <p>Ongoing pain: Visual Analogue Scale (VAS) and Numeric Rate Scale (NRS)</p> <p>Allodynia (soft foam brush)</p> <p>Hyperalgesia (von Frey monofilament 20 g)</p> <p>Flare</p> <p>For each endpoint, the area under the curve (AUC) was estimated from the start of stimulation to the end of stimulation by the trapezoidal rule. The individual AUC values for both periods were plotted to show the inter- and intra-subject variability. For each endpoint a mixed effect model was fitted with random effect subject and fixed effect visit. The estimate of intra-subject variance and the mean value were then used to estimate the sample size of a crossover study required to have a probability of 0.80 to detect a 25% change in the mean value. Analysis was done using GenStat 8<sup>th </sup>edition.</p> <p>Results</p> <p>Each endpoint achieved very good reproducibility for patients and NHV. Comparison between groups revealed trends towards:</p> <p>Faster habituation to painful stimuli in patients</p> <p>Bigger areas of hyperalgesia in patients</p> <p>Similar area of allodynia and flare (no statistical significance)</p> <p>Conclusion</p> <p>The differences demonstrated between patients and NHVs suggest that the electrical stimulation device used here may stimulate pathways that are affected in the pathological state.</p
ΠΠ΅ΡΠΎΠ΄ Π²ΠΎΡΡΡΠ°Π½ΠΎΠ²Π»Π΅Π½ΠΈΡ ΡΡΠ½ΠΊΡΠΈΠΈ Π²ΠΎΠ»Π½ΠΎΠ²ΠΎΠΉ Π°Π±Π΅ΡΡΠ°ΡΠΈΠΈ ΠΏΠΎ ΠΊΠ°ΡΡΠΈΠ½Π°ΠΌ ΠΈΠ·ΠΎΠ΄ΠΈΠΎΠΏΡΡΠΈΠΉΠ½ΡΡ Π·ΠΎΠ½ Π½Π° Π·ΡΠ°ΡΠΊΠ΅ Π³Π»Π°Π·Π°
ΠΠΎΠ»ΠΎΠ²Π½ΠΎΡ Π·Π°Π΄Π°ΡΠ΅Ρ Π΄Π°Π½ΠΎΡ ΡΠΎΠ±ΠΎΡΠΈ Ρ ΡΡΠ²ΠΎΡΠ΅Π½Π½Ρ ΠΌΠ°ΡΠ΅ΠΌΠ°ΡΠΈΡΠ½ΠΎΠ³ΠΎ Π°Π»Π³ΠΎΡΠΈΡΠΌΡ Π²ΡΠ΄Π½ΠΎΠ²Π»Π΅Π½Π½Ρ ΡΡΠ½ΠΊΡΡΡ Ρ
Π²ΠΈΠ»ΡΠΎΠ²ΠΎΡ Π°Π±Π΅ΡΠ°ΡΡΡ Π·Π° ΡΠ΅Π·ΡΠ»ΡΡΠ°ΡΠ°ΠΌΠΈ Π²ΡΠ΄Π΅ΠΎΠ·Π°ΠΏΠΈΡΡ ΠΊΠ°ΡΡΠΈΠ½ ΡΠ·ΠΎΠ΄ΡΠΎΠΏΡΡΡΠΉΠ½ΠΈΡ
Π·ΠΎΠ½ Ρ ΠΏΠ»ΠΎΡΠΈΠ½Ρ Π·ΡΠ½ΠΈΡΡ. ΠΠ΅ΡΡΠΎΡ ΠΏΡΠΎΡΠ΅Π΄ΡΡΠΎΡ Π²ΡΠ΄Π½ΠΎΠ²Π»Π΅Π½Π½Ρ Ρ ΡΠΈΡΡΠΎΠ²Π° ΡΡΠ»ΡΡΡΠ°ΡΡΡ Π²ΡΠ΄Π΅ΠΎΠΊΠ°Π΄ΡΡΠ² Π· ΠΌΠ΅ΡΠΎΡ Π²ΠΈΠ΄ΡΠ»Π΅Π½Π½Ρ ΡΠ·ΠΎΠ΄ΡΠΎΠΏΡΡΡΠΉΠ½ΠΈΡ
Π·ΠΎΠ½ ΠΎΡΠ²ΡΡΠ»Π΅Π½ΠΎΡΡΡ ΡΠΎΡΠΎΠΏΡΠΈΠΉΠΌΠ°ΡΠ°. ΠΡΡΠ³ΠΎΡ ΠΏΡΠΎΡΠ΅Π΄ΡΡΠΎΡ Ρ Π²ΠΈΡΠ²Π»Π΅Π½Π½Ρ ΠΊΡΡΠΎΠ²ΠΈΡ
ΠΊΠΎΠΎΡΠ΄ΠΈΠ½Π°Ρ ΠΏΡΠΎΠΌΠ΅Π½ΡΠ², ΡΠΎ Π²ΠΈΡ
ΠΎΠ΄ΡΡΡ Π· ΠΎΠΊΠ°. Π’ΡΠ΅ΡΡ ΠΏΡΠΎΡΠ΅Π΄ΡΡΠ° β Π²ΡΠ΄Π½ΠΎΠ²Π»Π΅Π½Π½Ρ ΡΡΠ½ΠΊΡΡΡ Ρ
Π²ΠΈΠ»ΡΠΎΠ²ΠΎΡ Π°Π±Π΅ΡΠ°ΡΡΡ Ρ Π·ΡΠ½ΠΈΡΠ½ΠΈΡ
ΠΊΠΎΠΎΡΠ΄ΠΈΠ½Π°ΡΠ°Ρ
. ΠΠ»Ρ ΡΡΠΎΠ³ΠΎ Π²ΠΈΠΊΠΎΡΠΈΡΡΠΎΠ²ΡΡΡΡΡΡ Π°ΠΏΡΠΎΠΊΡΠΈΠΌΠ°ΡΡΡ ΠΏΠΎΠ»ΡΠ½ΠΎΠΌΠ°ΠΌΠΈ Π¦Π΅ΡΠ½ΡΠΊΠ΅. ΠΠΌΠΏΠ»ΡΡΡΠ΄ΠΈ Π°Π±Π΅ΡΠ°ΡΡΠΉΠ½ΠΈΡ
ΠΌΠΎΠ΄ Π²ΡΠ΄Π½ΠΎΠ²Π»ΡΡΡΡΡΡ Π·Π° Π΄ΠΎΠΏΠΎΠΌΠΎΠ³ΠΎΡ ΠΌΠ΅ΡΠΎΠ΄Π° Π½Π°ΠΉΠΌΠ΅Π½ΡΠΈΡ
ΠΊΠ²Π°Π΄ΡΠ°ΡΡΠ² Π°Π±ΠΎ ΡΠΈΠ½Π³ΡΠ»ΡΡΠ½ΠΈΠΌ ΡΠΎΠ·ΠΊΠ»Π°Π΄ΠΎΠΌ.The main objective of this paper is to develop a mathematical algorithm for reconstruction of the wave aberration function, based on processing images of isodiopter zones, video-recorded at the pupil plane. To extract isodiopter zones from a photodetector illuminance picture, the first procedure should be digital filtering of video-images. The second procedure is to determine "in front of the eye" the angular coordinates of rays, emitting from the eye. These rays forms isodiopter zones in the pupil plane. The third procedure is to reconstruct the wave aberration function in pupil coordinates. For this purpose, the approximation with Zernike polynomials is applied. Amplitudes of aberration modes are reconstructed using the least-squares method or singular decomposition.ΠΠ»Π°Π²Π½ΠΎΠΉ Π·Π°Π΄Π°ΡΠ΅ΠΉ Π΄Π°Π½Π½ΠΎΠΉ ΡΠ°Π±ΠΎΡΡ ΡΠ²Π»ΡΠ΅ΡΡΡ ΡΠΎΠ·Π΄Π°Π½ΠΈΠ΅ ΠΌΠ°ΡΠ΅ΠΌΠ°ΡΠΈΡΠ΅ΡΠΊΠΎΠ³ΠΎ Π°Π»Π³ΠΎΡΠΈΡΠΌΠ° Π²ΠΎΡΡΡΠ°Π½ΠΎΠ²Π»Π΅Π½ΠΈΡ ΡΡΠ½ΠΊΡΠΈΠΈ Π²ΠΎΠ»Π½ΠΎΠ²ΠΎΠΉ Π°Π±Π΅ΡΡΠ°ΡΠΈΠΈ ΠΏΠΎ ΡΠ΅Π·ΡΠ»ΡΡΠ°ΡΠ°ΠΌ Π²ΠΈΠ΄Π΅ΠΎΠ·Π°ΠΏΠΈΡΠΈ ΠΊΠ°ΡΡΠΈΠ½ ΠΈΠ·ΠΎΠ΄ΠΈΠΎΠΏΡΡΠΈΠΉΠ½ΡΡ
Π·ΠΎΠ½ Π² ΠΏΠ»ΠΎΡΠΊΠΎΡΡΠΈ Π·ΡΠ°ΡΠΊΠ°. ΠΠ΅ΡΠ²ΠΎΠΉ ΠΏΡΠΎΡΠ΅Π΄ΡΡΠΎΠΉ Π²ΠΎΡΡΡΠ°Π½ΠΎΠ²Π»Π΅Π½ΠΈΡ ΡΠ²Π»ΡΠ΅ΡΡΡ ΡΠΈΡΡΠΎΠ²Π°Ρ ΡΠΈΠ»ΡΡΡΠ°ΡΠΈΡ Π²ΠΈΠ΄Π΅ΠΎΠΊΠ°Π΄ΡΠΎΠ² Ρ ΡΠ΅Π»ΡΡ Π²ΡΠ΄Π΅Π»Π΅Π½ΠΈΡ ΠΈΠ·ΠΎΠ΄ΠΈΠΎΠΏΡΡΠΈΠΉΠ½ΡΡ
Π·ΠΎΠ½ ΠΎΡΠ²Π΅ΡΠ΅Π½Π½ΠΎΡΡΠΈ ΡΠΎΡΠΎΠΏΡΠΈΠ΅ΠΌΠ½ΠΈΠΊΠ°. ΠΡΠΎΡΠΎΠΉ ΠΏΡΠΎΡΠ΅Π΄ΡΡΠΎΠΉ ΡΠ²Π»ΡΠ΅ΡΡΡ ΠΎΠΏΡΠ΅Π΄Π΅Π»Π΅Π½ΠΈΠ΅ ΡΠ³Π»ΠΎΠ²ΡΡ
ΠΊΠΎΠΎΡΠ΄ΠΈΠ½Π°Ρ ΠΈΡΡ
ΠΎΠ΄ΡΡΠΈΡ
ΠΈΠ· Π³Π»Π°Π·Π° Π»ΡΡΠ΅ΠΉ. Π’ΡΠ΅ΡΡΡ ΠΏΡΠΎΡΠ΅Π΄ΡΡΠ° β Π²ΠΎΡΡΡΠ°Π½ΠΎΠ²Π»Π΅Π½ΠΈΠ΅ ΡΡΠ½ΠΊΡΠΈΠΈ Π²ΠΎΠ»Π½ΠΎΠ²ΠΎΠΉ Π°Π±Π΅ΡΡΠ°ΡΠΈΠΈ Π² Π·ΡΠ°ΡΠΊΠΎΠ²ΡΡ
ΠΊΠΎΠΎΡΠ΄ΠΈΠ½Π°ΡΠ°Ρ
. ΠΠ»Ρ ΡΡΠΎΠ³ΠΎ ΠΈΡΠΏΠΎΠ»ΡΠ·ΡΠ΅ΡΡΡ Π°ΠΏΠΏΡΠΎΠΊΡΠΈΠΌΠ°ΡΠΈΡ ΠΏΠΎΠ»ΠΈΠ½ΠΎΠΌΠ°ΠΌΠΈ Π¦Π΅ΡΠ½ΠΈΠΊΠ΅. ΠΠΌΠΏΠ»ΠΈΡΡΠ΄Ρ Π°Π±Π΅ΡΡΠ°ΡΠΈΠΎΠ½Π½ΡΡ
ΠΌΠΎΠ΄ Π²ΠΎΡΡΡΠ°Π½Π°Π²Π»ΠΈΠ²Π°ΡΡΡΡ ΠΏΠΎΡΡΠ΅Π΄ΡΡΠ²ΠΎΠΌ ΠΌΠ΅ΡΠΎΠ΄Π° Π½Π°ΠΈΠΌΠ΅Π½ΡΡΠΈΡ
ΠΊΠ²Π°Π΄ΡΠ°ΡΠΎΠ² ΠΈΠ»ΠΈ ΡΠΈΠ½Π³ΡΠ»ΡΡΠ½ΠΎΠ³ΠΎ ΡΠ°Π·Π»ΠΎΠΆΠ΅Π½ΠΈΡ
Π ΠΠΠΠ ΠΠΠΠΠ§ΠΠ‘Π’ΠΠ’ΠΠΠ ΠΠΠΠΠ ΠΠ¦ΠΠ Π ΠΠΠ’ΠΠΠΠΠΠ’Π ΠΠΠΠΠ ΠΠΠΠΠ ΠΠ’ΠΠ Π Π‘ΠΠ§ ΠΠ ΠΠΠΠΠ―Π₯ ΠΠΠΠΠ ΠΠΠ Π‘ ΠΠΠ’ΠΠ§ΠΠ‘ΠΠΠ Π£Π‘ΠΠΠΠΠΠΠ
The theoretical investigation of the single-frequency oscillation in all-optical gain optoelectronic oscillator based on fiberoptic delay lines is performed. It is shown that there is no need in microwave phase shifters within the optoelectronic oscillator loop in order to provide low phase noise and spurious level oscillations. Threshold of the dynamical instabilities in the all-optical gain optoelectronic oscillator is calculated. It is shown that the reproducibility of the oscillation frequency is provided by means of the continuous tuning of the loop gain during the switching-on.Β Π Π΄Π°Π½Π½ΠΎΠΉ ΡΠ°Π±ΠΎΡΠ΅ ΠΏΡΠΎΠ²Π΅Π΄Π΅Π½ΠΎ ΡΠ΅ΠΎΡΠ΅ΡΠΈΡΠ΅ΡΠΊΠΎΠ΅ ΠΈΡΡΠ»Π΅Π΄ΠΎΠ²Π°Π½ΠΈΠ΅ ΠΊΠ²Π°Π·ΠΈΠ³Π°ΡΠΌΠΎΠ½ΠΈΡΠ΅ΡΠΊΠΎΠΉ Π³Π΅Π½Π΅ΡΠ°ΡΠΈΠΈ Π² ΠΎΠΏΡΠΎΡΠ»Π΅ΠΊΡΡΠΎΠ½Π½ΠΎΠΌ Π³Π΅Π½Π΅ΡΠ°ΡΠΎΡΠ΅ Π½Π° Π»ΠΈΠ½ΠΈΡΡ
Π·Π°Π΄Π΅ΡΠΆΠΊΠΈ Ρ ΠΎΠΏΡΠΈΡΠ΅ΡΠΊΠΈΠΌ ΡΡΠΈΠ»Π΅Π½ΠΈΠ΅ΠΌ. Π Π°ΡΡΠΌΠ°ΡΡΠΈΠ²Π°ΡΡΡΡ ΠΎΡΠΎΠ±Π΅Π½Π½ΠΎΡΡΠΈ ΠΏΡΠΈΠΌΠ΅Π½Π΅Π½ΠΈΡ Π‘ΠΠ§-ΡΠ°Π·ΠΎΠ²ΡΠ°ΡΠ°ΡΠ΅Π»Π΅ΠΉ Π΄Π»Ρ ΠΎΠ±Π΅ΡΠΏΠ΅ΡΠ΅Π½ΠΈΡ ΠΊΠ²Π°Π·ΠΈΠ³Π°ΡΠΌΠΎΠ½ΠΈΡΠ΅ΡΠΊΠΎΠΉ Π³Π΅Π½Π΅ΡΠ°ΡΠΈΠΈ Ρ Π½ΠΈΠ·ΠΊΠΈΠΌ ΡΠ°Π·ΠΎΠ²ΡΠΌ ΡΡΠΌΠΎΠΌ ΠΈ ΡΡΠΎΠ²Π½Π΅ΠΌ Π΄ΠΈΡΠΊΡΠ΅ΡΠ½ΡΡ
ΡΠΎΡΡΠ°Π²Π»ΡΡΡΠΈΡ
Π² ΡΠΏΠ΅ΠΊΡΡΠ΅ Π³Π΅Π½Π΅ΡΠ°ΡΠΈΠΈ, Π° ΡΠ°ΠΊΠΆΠ΅ ΡΠ°ΡΡΡΠΈΡΠ°Π½ΠΎ ΠΏΠΎΡΠΎΠ³ΠΎΠ²ΠΎΠ΅ Π·Π½Π°ΡΠ΅Π½ΠΈΠ΅ ΠΊΠΎΡΡΡΠΈΡΠΈΠ΅Π½ΡΠ° ΡΡΠΈΠ»Π΅Π½ΠΈΡ ΠΊΠΎΠ½ΡΡΡΠ° ΠΎΠ±ΡΠ°ΡΠ½ΠΎΠΉ ΡΠ²ΡΠ·ΠΈ, ΠΏΡΠΈ ΠΊΠΎΡΠΎΡΠΎΠΌ Π² ΠΎΠΏΡΠΎΡΠ»Π΅ΠΊΡΡΠΎΠ½Π½ΠΎΠΌ Π³Π΅Π½Π΅ΡΠ°ΡΠΎΡΠ΅ Π½Π° Π»ΠΈΠ½ΠΈΡΡ
Π·Π°Π΄Π΅ΡΠΆΠΊΠΈ Ρ ΠΎΠΏΡΠΈΡΠ΅ΡΠΊΠΈΠΌ ΡΡΠΈΠ»Π΅Π½ΠΈΠ΅ΠΌ Π½Π°ΡΡΡΠΏΠ°Π΅Ρ ΡΠ΅ΠΆΠΈΠΌ Π΄ΠΈΠ½Π°ΠΌΠΈΡΠ΅ΡΠΊΠΈΡ
Π½Π΅ΡΡΠ°Π±ΠΈΠ»ΡΠ½ΠΎΡΡΠ΅ΠΉ Π³Π΅Π½Π΅ΡΠ°ΡΠΈΠΈ. ΠΡΠ΅Π΄Π»ΠΎΠΆΠ΅Π½ ΠΌΠ΅ΡΠΎΠ΄ ΠΎΠ±Π΅ΡΠΏΠ΅ΡΠ΅Π½ΠΈΡ ΡΡΡΠ°Π½ΠΎΠ²Π»Π΅Π½ΠΈΡ Π³Π΅Π½Π΅ΡΠ°ΡΠΈΠΈ Π² ΠΎΠΏΡΠΎΡΠ»Π΅ΠΊΡΡΠΎΠ½Π½ΠΎΠΌ Π³Π΅Π½Π΅ΡΠ°ΡΠΎΡΠ΅ Π½Π° ΡΠ°ΡΡΠΎΡΠ΅ ΠΌΠ°ΠΊΡΠΈΠΌΠ°Π»ΡΠ½ΠΎΠ³ΠΎ ΡΡΠΈΠ»Π΅Π½ΠΈΡ.
Π’Π΅ΠΏΠ»ΠΎΡΠΈΠ·ΠΈΡΠ΅ΡΠΊΠΈΠ΅ ΡΠ²ΠΎΠΉΡΡΠ²Π° ΠΈ ΡΡΡΡΠΊΡΡΡΠ° ΠΎΡΠ»ΠΎΠΆΠ΅Π½ΠΈΠΉ Π½Π° ΠΏΠΎΠ²Π΅ΡΡ Π½ΠΎΡΡΡΡ Π½Π°Π³ΡΠ΅Π²Π° ΡΠ½Π΅ΡΠ³Π΅ΡΠΈΡΠ΅ΡΠΊΠΎΠ³ΠΎ ΠΎΠ±ΠΎΡΡΠ΄ΠΎΠ²Π°Π½ΠΈΡ
The paper shows influence of heating surface material, design peculiarities, operational conditions of heat exchangers and water-chemical regime on chemical and structural composition of deposits, their heat conduction and porosity.ΠΠΎΠΊΠ°Π·Π°Π½ΠΎ Π²Π»ΠΈΡΠ½ΠΈΠ΅ ΠΌΠ°ΡΠ΅ΡΠΈΠ°Π»Π° ΠΏΠΎΠ²Π΅ΡΡ
Π½ΠΎΡΡΠΈ Π½Π°Π³ΡΠ΅Π²Π°, ΠΊΠΎΠ½ΡΡΡΡΠΊΡΠΈΠ²Π½ΡΡ
ΠΎΡΠΎΠ±Π΅Π½Π½ΠΎΡΡΠ΅ΠΉ, ΡΡΠ»ΠΎΠ²ΠΈΠΉ ΡΠΊΡΠΏΠ»ΡΠ°ΡΠ°ΡΠΈΠΈ ΡΠ΅ΠΏΠ»ΠΎΠΎΠ±ΠΌΠ΅Π½Π½ΡΡ
ΡΡΡΡΠΎΠΉΡΡΠ² ΠΈ Π²ΠΎΠ΄Π½ΠΎ-Ρ
ΠΈΠΌΠΈΡΠ΅ΡΠΊΠΎΠ³ΠΎ ΡΠ΅ΠΆΠΈΠΌΠ° Π½Π° Ρ
ΠΈΠΌΠΈΡΠ΅ΡΠΊΠΈΠΉ ΠΈ ΡΡΡΡΠΊΡΡΡΠ½ΡΠΉ ΡΠΎΡΡΠ°Π² ΠΎΡΠ»ΠΎΠΆΠ΅Π½ΠΈΠΉ, ΠΈΡ
ΡΠ΅ΠΏΠ»ΠΎΠΏΡΠΎΠ²ΠΎΠ΄Π½ΠΎΡΡΡ ΠΈ ΠΏΠΎΡΠΈΡΡΠΎΡΡΡ
The Role of Interdiffusion and Spatial Confinement in the Formation of Resonant Raman Spectra of Ge/Si(100) Heterostructures with Quantum-Dot Arrays
The phonon modes of self-assembled Ge/Si quantum dots grown by molecular-beam
epitaxy in an apparatus integrated with a chamber of the scanning tunneling
microscope into a single high-vacuum system are investigated using Raman
spectroscopy. It is revealed that the Ge-Ge and Si-Ge vibrational modes are
considerably enhanced upon excitation of excitons between the valence band
and the conduction band (the E1 and E1 +
transitions). This makes it possible to observe the Raman spectrum of very
small amounts of germanium, such as one layer of quantum dots with a germanium
layer thickness of 10 \r{A}. The enhancement of these modes suggests a strong
electron-phonon interaction of the vibrational modes with the E1 and E1 +
excitons in the quantum dot. It is demonstrated that the frequency
of the Ge-Ge mode decreases by 10 cm^-1 with a decrease in the thickness of the
Ge layer from 10 to 6 \r{A} due to the spatial-confinement effect. The optimum
thickness of the Ge layer, for which the size dispersion of quantum dots is
minimum, is determined.Comment: 14 pages, 9 figure
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