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Quantum dots for temperature sensing

Doskaliuk Natalia, Lukan Yuliana, Khalavka Yuriy

Scientiae Radices

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2023

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Vol. 2, Iss. 2

93--111

EN

Quantum dots are three-dimensional nanoparticles of semiconductors with typical sizes ranging from 2 to 10 nm. Due to the quantum confinement effect the energy gap increase with the size decreasing resulting in size-depended and fine-tunable optical characteristics. Besides this, the energy structure of a quantum dot with a certain size is highly sensitive to environmental conditions. These specific properties open a wide range of applications starting from optical and optoelectronic devices and ending with biosensing and life science. Temperature is one of those parameters influencing strongly on the optical properties of semiconductor nanocrystals, which make them promising materials for temperature sensing, more often using a fluorescent response. Compared to the conventional organic dyes already applied in this field, quantum dots exhibit a set of advantages, such as high quantum yield and photostability, long fluorescence lifetime, higher Stokes shift, and ability to surface functionalization with targeted organic molecules aimed to provide them biocompatibility. In this review, we briefly discuss the properties of II-VI and assumingly less toxic I-III-VI quantum dots, mechanisms of temperature-induced fluorescence response, and the feasibility of their practical application in the field of thermal sensing.

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Temperature sensitivity of solid heterogeneous rocket propellant AP/HTPB/AI

Florczak Bogdan

Materiały Wysokoenergetyczne

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2019

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T. 11(2)

83--88

EN

The results of research on solid heterogeneous rocket propellant (SHRP) containing: ammonium chlorate(VII) (AP) as an oxidant, a binder based on liquid synthetic rubber, i.e. hydroxylterminated polybutadiene (HTPB), aluminium (Al) and technological additives in a laboratory rocket motor (LRM) are presented to determine the thermal sensitivity of the propellant.

PL

Przedstawiono wyniki z badań stałego heterogenicznego paliwa rakietowego (SHPR) zawierającego jako główne składniki: chloran(VII) amonu (AP) jako utleniacz, lepiszcze na bazie ciekłego syntetycznego kauczuku (HTPB), glin (Al) oraz dodatki technologiczne w laboratoryjnym silniku rakietowym (LSR) pozwalające na wyznaczenie wrażliwości termicznej paliwa.

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Properties of a fibre optic strain sensor in the configuration of a Mach-Zehnder modal interferometer with a polarization maintaining photonic crystal fibre

Kaczmarek C.

Metrology and Measurement Systems

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2018

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Vol. 25, nr 2

417--424

EN

The paper presents the properties of a strain sensor, which was made using the micro hole collapse method and operates in the configuration of a Mach-Zehnder modal interferometer with a PM-1550-01 polarization maintaining photonic crystal fibre. The sensor’s transfer curve was determined analytically. Its strain sensitivity, determined from measurements, decreases slightly with increasing wavelength and is in a range from -2.01 to -2.23 pm/με in the wavelength range 1520-1580 nm. Based on the Fourier analysis of the wavelength spectrum of the constructed sensor, the difference of the group refractive indices of the core and the cladding of the photonic crystal fibre was determined, which are in a range from 7.45·10-3 to 1.01·10-2. The temperature sensitivity of the sensor, determined on the basis of measurements performed in a range from 23 to 60°C, is positive and equals 5.9 pm/K.

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Temperature Sensitivity of Propellant Combustion and Temperature Coefficients of Gun Performance

Boulkadid M. K., Lefebvre M. H., Jeunieau L., Dejeaifve A.

Central European Journal of Energetic Materials

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2016

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Vol. 13, no. 4

1005--1022

EN

One of the objectives of gun propellant research is to develop green formulations of gunpowder that should be less temperature sensitive than the current gun propellant. The temperature sensitivity of these new green formulations of the propellant should be measured to identify the less temperature sensitive green formulations. However, there are deficiencies in the methodologies for the measurement of the temperature sensitivity of gun propellants. Therefore, the aim of this investigation was to fill the gap by establishing a method for the measurement of the temperature sensitivity of deterred gun propellants by closed vessel tests. The temperature sensitivity of the burning rate of ball propellants and the temperature coefficients of gun performance were determined using closed vessel tests and ballistic firing, respectively. Specific definitions of temperature sensitivity and temperature coefficients were evaluated. The relation between these parameters has never been explicitly investigated previously. Assessing the temperature sensitivity of propellants by closed vessel tests is of added value to the range of ballistic tests if the results of these tests can be well correlated to the results of ballistic firings. Therefore, a comparison between both parameters was made. A correspondence has been observed between the temperature sensitivity of the propellant burning rate, as obtained from closed vessel tests, and the temperature coefficients as obtained from ballistic firings.

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On the design of biodegradable hydrogels both thermosensitive and pH sensitive

Wang B., Guo Y., Hu G.

Materials Science Poland

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2010

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Vol. 28, No. 1

207--215

EN

A Pluronic oligo(?-caprolactone) block copolymer has been synthesized by ring opening polymerization of ?-caprolactone monomers in the presence of poly(ethylene oxide)-poly(propylene oxide) -poly(ethylene oxide) triblock copolymers, using stannous octoate as a catalyst, and then the block copolymer was terminated with an acryloyl group. A novel biodegradable pH- and temperature sensitive hydrogel has been fabricated by free radical copolymerization of diacylated macromer-methacrylic acid aqueous solution initiated by a redox initiator. The structures of products were characterized by the Fourier transform infrared spectroscopy. Variations of the equilibrium swelling ratio in various environmental solutions confirmed the pH- and temperature sensitivity of hydrogel, which were affected by the MAA content.