274 research outputs found
Design of the Model of Ratiometric Polymer Nanobiothermometer Based on Quantum Dots
To solve many modern biological and biotechnological tasks it is necessary to realize strictly control and regulation of temperature of the cells and their organelles. Thi stasks include control of various exo- and endothermic reactions, monitoring of tissuesβ and individual cellβs temperature in in vitro researches and in vivo procedures such as the hyperthermia procedure that used for cancer treatment. The today known methods of measuring and controlling of temperature at the cellular level can not provide the necessary level of locality and accuracy due to too big size and heightened sensitivity to external factors. The real alternative of existing today methods is nanoscale temperature biosensor operating on a ratiometric principle and based on the composite structure from polymers and colloidal quantum dots. In this paper we present a working model and plan of investigation of ratiometric nanoscale polymer nanobiothermometer based on quantum dots.
Keywords: thermosensors, quantum dots, local temperature, polymers, temperature measuremen
Correlative Microscopy: A Potent Tool for Biomedicine
The correlative microscopy method based on a combination of optical and electronic techniques that is increasingly widely used now, has a number of limitations. Here, an alternative approach is considered that uses scanning probe microscopy (SPM) technique to get high-resolution and ultra-high-resolution data. SPM greatly increases the possibilities of collecting new information (on topological, morphological, electrical, magnetic etc. properties). To obtain three-dimensional distributions of different parameters of the sample, ultramicrotomography is used, which allows to scan the sample in steps of up to 20 nm. The principal advantage of the approach is that spectral data are used which due to the combination in near field microscopy can be gained with high and ultrahigh resolution. All above mentioned features are implemented in a single instrument, which allows to have 3-D data and their distributions at the same instrumental platform. A special feature of the approach is the possibility to use all the power of micro(nano)spectral methods. Therefore, it would be more correct to name the proposed approach βCorrelative microspectroscopyβ.
Keywords: correlative microscopy, correlative microspectroscopy, scanning near-ielf optical microscopy, ultramicrotomography, Raman, TER
Technology for Creation and Detailed Analysis of Polymer Composites with Uniform Distribution of Quantum Dots and Liquid Crystals
One of the most actual tasks in biotechnology is the creation of a new generation of nanobiosensors with improved brightness, photo stability, and sensitivity. Compositions of polymers and colloidal quantum dots (QDs) are the most promising base to develop such sensors. This work presents the technology for creation and detailed analysis of nanostructured composite films based on polypropylene matrices with uniformly distributed CdSe/ZnS quantum dots and liquid crystals. Methods of optical microscopy, scanning probe microscopy and confocal fluorescen tmicrospectroscopy were used. The presence of liquid crystals in the composite allows additional control of QDs fluorescence. The methodology proposed is applicable not only to polypropylene, but also to other porous polymers. The results of this work indicate the possibility of creating high-quality polymer/QDs composite materials and open the way to the development of nanomaterials (nanosensors) with optical properties sensitive to various environmental parameters (electric field, photo irradiation, mechanical action, etc.).
Keywords: quantum dot-polymer composites, nanoporous polypropylene, fluorescenc
Indication on the universal hadron substructure - constituent quarks
The universality of single-spin asymmetry on inclusive pi-meson production is
discussed. This universality can be related to the hadron substructure -
constituent quarks.Comment: 3 pages, 3 figures, references adde
ΠΠ»ΠΈΡΠ½ΠΈΠ΅ ΡΠ΅Π³ΡΠ»ΡΡΠΎΡΠΎΠ² ΡΠΎΡΡΠ° ΡΠ°ΡΡΠ΅Π½ΠΈΠΉ Π½Π° Π²ΠΎΠ·ΠΌΠΎΠΆΠ½ΠΎΡΡΡ ΡΠ½ΠΈΠΆΠ΅Π½ΠΈΡ ΠΈΠ½ΡΠ΅ΠΊΡΠΈΡΠΈΠ΄Π½ΠΎΠΉ Π½Π°Π³ΡΡΠ·ΠΊΠΈ Π² Π°Π³ΡΠΎΡΠ΅Π½ΠΎΠ·Π°Ρ ΠΎΠ·ΠΈΠΌΠΎΠΉ ΠΏΡΠ΅Π½ΠΈΡΡ
Insecticides BI-58 new and Diazinone decrease the extent of damage of the winter wheat culm by cereals flies 7,2β8,0 times in comparison with the control. Combination of the studied insecticides with the mixtures of growth regulators allows to decrease the rate of insecticides application by 20 % without any increase of the culms damage by the pests.ΠΠΎΠΊΠ°Π·Π°Π½ΠΎ, ΡΠΎ ΡΠ½ΡΠ΅ΠΊΡΠΈΡΠΈΠ΄ΠΈ ΠΠ-58 Π½ΠΎΠ²ΠΈΠΉ ΡΠ° ΠΡΠ°Π·ΠΈΠ½ΠΎΠ½ Π·Π½ΠΈΠΆΡΡΡΡ ΡΡΡΠΏΡΠ½Ρ ΠΏΠΎΡΠΊΠΎΠ΄ΠΆΠ΅Π½Π½Ρ ΡΡΠ΅Π±Π»ΠΈΠ½ ΠΎΠ·ΠΈΠΌΠΎΡ ΠΏΡΠ΅Π½ΠΈΡΡ Π·Π»Π°ΠΊΠΎΠ²ΠΈΠΌΠΈ ΠΌΡΡ
Π°ΠΌΠΈ Π² 7,2β8 ΡΠ°Π·ΡΠ² ΠΏΠΎΡΡΠ²Π½ΡΠ½ΠΎ Π· ΠΊΠΎΠ½ΡΡΠΎΠ»Π΅ΠΌ. ΠΡΠΈ Π·Π½ΠΈΠΆΠ΅Π½Π½Ρ Π½ΠΎΡΠΌ Π²ΠΈΡΡΠ°Ρ Π΄ΠΎΡΠ»ΡΠ΄ΠΆΠ΅Π½ΠΈΡ
ΡΠ½ΡΠ΅ΠΊΡΠΈΡΠΈΠ΄ΡΠ² Ρ Π±Π°ΠΊΠΎΠ²ΠΈΡ
ΡΡΠΌΡΡΠ°Ρ
ΡΠ· ΡΠ΅Π³ΡΠ»ΡΡΠΎΡΠ°ΠΌΠΈ ΡΠΎΡΡΡ ΡΠΎΡΠ»ΠΈΠ½ (Π±ΡΠΎΠ³ΡΠΌΠ°ΡΠΎΠΌ, ΡΡΠΈΠΌΠ°Π½ΠΎΠΌβ1, Π΅ΠΌΡΡΡΠΈΠΌΠΎΠΌ Π‘) Π½Π° 20 % ΠΊΡΠ»ΡΠΊΡΡΡΡ ΠΏΠΎΡΠΊΠΎΠ΄ΠΆΠ΅Π½ΠΈΡ
ΡΡΠ΅Π±Π»ΠΈΠ½ ΠΏΡΠΈΡ
ΠΎΠ²Π°Π½ΠΎ ΡΡΠ΅Π±Π»ΠΎΠ²ΠΈΠΌΠΈ ΡΠΊΡΠ΄Π½ΠΈΠΊΠ°ΠΌΠΈ (Π·Π»Π°ΠΊΠΎΠ²ΠΈΠΌΠΈ ΠΌΡΡ
Π°ΠΌΠΈ) Π·Π°Π»ΠΈΡΠ°ΡΡΡΡΡ Π½Π° ΡΡΠ²Π½Ρ Π²ΠΈΠΊΠΎΡΠΈΡΡΠ°Π½Π½Ρ ΠΏΠΎΠ²Π½ΠΈΡ
Π΄ΠΎΠ·.ΠΠΎΠΊΠ°Π·Π°Π½ΠΎ, ΡΠΎ ΡΠ½ΡΠ΅ΠΊΡΠΈΡΠΈΠ΄ΠΈ ΠΠ-58 Π½ΠΎΠ²ΠΈΠΉ ΡΠ° ΠΡΠ°Π·ΠΈΠ½ΠΎΠ½ Π·Π½ΠΈΠΆΡΡΡΡ ΡΡΡΠΏΡΠ½Ρ ΠΏΠΎΡΠΊΠΎΠ΄ΠΆΠ΅Π½Π½Ρ ΡΡΠ΅Π±Π»ΠΈΠ½ ΠΎΠ·ΠΈΠΌΠΎΡ ΠΏΡΠ΅Π½ΠΈΡΡ Π·Π»Π°ΠΊΠΎΠ²ΠΈΠΌΠΈ ΠΌΡΡ
Π°ΠΌΠΈ Π² 7,2β8 ΡΠ°Π·ΡΠ² ΠΏΠΎΡΡΠ²Π½ΡΠ½ΠΎ Π· ΠΊΠΎΠ½ΡΡΠΎΠ»Π΅ΠΌ. ΠΡΠΈ Π·Π½ΠΈΠΆΠ΅Π½Π½Ρ Π½ΠΎΡΠΌ Π²ΠΈΡΡΠ°Ρ Π΄ΠΎΡΠ»ΡΠ΄ΠΆΠ΅Π½ΠΈΡ
ΡΠ½ΡΠ΅ΠΊΡΠΈΡΠΈΠ΄ΡΠ² Ρ Π±Π°ΠΊΠΎΠ²ΠΈΡ
ΡΡΠΌΡΡΠ°Ρ
ΡΠ· ΡΠ΅Π³ΡΠ»ΡΡΠΎΡΠ°ΠΌΠΈ ΡΠΎΡΡΡ ΡΠΎΡΠ»ΠΈΠ½ (Π±ΡΠΎΠ³ΡΠΌΠ°ΡΠΎΠΌ, ΡΡΠΈΠΌΠ°Π½ΠΎΠΌβ1, Π΅ΠΌΡΡΡΠΈΠΌΠΎΠΌ Π‘) Π½Π° 20 % ΠΊΡΠ»ΡΠΊΡΡΡΡ ΠΏΠΎΡΠΊΠΎΠ΄ΠΆΠ΅Π½ΠΈΡ
ΡΡΠ΅Π±Π»ΠΈΠ½ ΠΏΡΠΈΡ
ΠΎΠ²Π°Π½ΠΎ ΡΡΠ΅Π±Π»ΠΎΠ²ΠΈΠΌΠΈ ΡΠΊΡΠ΄Π½ΠΈΠΊΠ°ΠΌΠΈ (Π·Π»Π°ΠΊΠΎΠ²ΠΈΠΌΠΈ ΠΌΡΡ
Π°ΠΌΠΈ) Π·Π°Π»ΠΈΡΠ°ΡΡΡΡΡ Π½Π° ΡΡΠ²Π½Ρ Π²ΠΈΠΊΠΎΡΠΈΡΡΠ°Π½Π½Ρ ΠΏΠΎΠ²Π½ΠΈΡ
Π΄ΠΎΠ·
First study of radiation hardness of lead tungstate crystals at low temperatures
The electromagnetic calorimeter of PANDA at the FAIR facility will rely on an
operation of lead tungstate (PWO) scintillation crystals at temperatures near
-25 deg.C to provide sufficient resolution for photons in the energy range from
8 GeV down to 10 MeV. Radiation hardness of PWO crystals was studied at the
IHEP (Protvino) irradiation facility in the temperature range from room
temperature down to -25 deg.C. These studies have indicated a significantly
different behaviour in the time evolution of the damaging processes well below
room temperature. Different signal loss levels at the same dose rate, but at
different temperatures were observed. The effect of a deep suppression of the
crystal recovery process at temperatures below
0 deg.C has been seen.Comment: 10 pages 7 figure
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