Metamorphic Pressure‐Temperature‐Time Paths

An analysis was performed of various estimates of the adiabatic temperature Ttot that corresponds to the total heat liberated by a gas dose adsorbed on a metal film in the calorimeter for measurement of chemisorption enthalpies. Besides the two common procedures consisting either in the construction of the adiabatic temperature-time curve or in the extrapolation of the single-exponential cooling part of the actual temperature-time curve to zero time, we have examined estimates of Ttot by extrapolating the cooling exponential to the mid-point between zero time and the temperature maximum (t = tmax/2). Model calculations have shown the merit of the latter extrapolation, particularly in the cases of slow heat evolution. This has been verified on the data measured in the chemisorption of methane and ethane on molybdenum films. Extrapolation to tmax/2 has turned out to be a simple and reasonably reliable procedure for handling the data obtained in film calorimeters.

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The effect of streambed heterogeneity on groundwater-surface water exchange fluxes inferred from temperature time series

Water Resources Research ◽

10.1002/2014wr015769 ◽

2015 ◽

Vol 51 (1) ◽

pp. 198-212 ◽

Cited By ~ 38

Author(s):

Dylan J. Irvine ◽

Roger H. Cranswick ◽

Craig T. Simmons ◽

Margaret A. Shanafield ◽

Laura K. Lautz

Keyword(s):

Time Series ◽

Surface Water ◽

Water Exchange ◽

Temperature Time Series ◽

Temperature Time ◽

Streambed Heterogeneity

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Development of Quantum Dot (QD) Based Color Converters for Multicolor Display

Nanomaterials ◽

10.3390/nano11051089 ◽

2021 ◽

Vol 11 (5) ◽

pp. 1089

Author(s):

Muhammad T. Sajjad ◽

Ashu K. Bansal ◽

Francesco Antolini ◽

Eduard Preis ◽

Lenuta Stroea ◽

...

Keyword(s):

Polymer Matrix ◽

Cost Effective ◽

Final Size ◽

Force Microscopy ◽

Morphological Studies ◽

Color Displays ◽

Transmission Electron ◽

Different Temperatures ◽

Color Conversion ◽

Temperature Time

Many displays involve the use of color conversion layers. QDs are attractive candidates as color converters because of their easy processability, tuneable optical properties, high photoluminescence quantum yield, and good stability. Here, we show that emissive QDs with narrow emission range can be made in-situ in a polymer matrix, with properties useful for color conversion. This was achieved by blending the blue-emitting pyridine based polymer with a cadmium selenide precursor and baking their films at different temperatures. To achieve efficient color conversion, blend ratio and baking temperature/time were varied. We found that thermal decomposition of the precursor leads to highly emissive QDs whose final size and emission can be controlled using baking temperature/time. The formation of the QDs inside the polymer matrix was confirmed through morphological studies using atomic force microscopy (AFM) and transmission electron microscopy (TEM). Hence, our approach provides a cost-effective route to making highly emissive color converters for multi-color displays.

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Application of Scattering Parameters to DPL Time-Lag Parameter Estimation at Nanoscale in Modern Integration Circuit Structures

Energies ◽

10.3390/en14154425 ◽

2021 ◽

Vol 14 (15) ◽

pp. 4425

Author(s):

Mariusz Zubert ◽

Zbigniew Kulesza ◽

Mariusz Jankowski ◽

Andrzej Napieralski

Keyword(s):

Integrated Circuits ◽

Time Lag ◽

Estimation Procedure ◽

Micro Electro Mechanical System ◽

Hafnium Dioxide ◽

Parameters Estimation ◽

Phase Lag ◽

Scattering Parameters ◽

Materials Used ◽

Temperature Time

This paper presents the methodology of material parameters’ estimation for the dual-phase-lag (DPL) model at the nanoscale in modern integration circuit (IC) structures. The analyses and measurements performed were used in the unique dedicated micro-electro-mechanical system (MEMS) test structure. The electric and thermal domain of this structure was analysed. Finally, the silicon dioxide (SiO2) temperature time-lag estimation procedure is presented based on the scattering parameters measured by a vector network analyser for the considered MEMS structure together with the 2-omega method. The proposed methodology has the ability to estimate the time-lag parameter with high accuracy and is also suitable for the temperature time-lag estimation for other manufacturing process technologies of ICs and other insulation materials used for integrated circuits such as silicon nitride (Si3N4), titanium nitride (TiN), and hafnium dioxide (HfO2).

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Changes of Physicochemical Properties of Starch Syrups Recommended for Winter Feeding of Honeybees during Storage

Agriculture ◽

10.3390/agriculture11040374 ◽

2021 ◽

Vol 11 (4) ◽

pp. 374

Author(s):

Teresa Szczęsna ◽

Ewa Waś ◽

Piotr Semkiw ◽

Piotr Skubida ◽

Katarzyna Jaśkiewicz ◽

...

Keyword(s):

Chemical Composition ◽

Physicochemical Properties ◽

Physicochemical Parameters ◽

Storage Temperature ◽

Storage Conditions ◽

Different Temperatures ◽

And Storage ◽

Bee Colonies ◽

Temperature Time ◽

Winter Feeding

The aim of this study was to determine the influence of storage temperature and time on physicochemical parameters of starch syrups recommended for the winter feeding of bee colonies. The studies included commercially available three starch syrups and an inverted saccharose syrup that were stored at different temperatures: ca. 20 °C, 10–14 °C, and ca. 4 °C. Physicochemical parameters of fresh syrups (immediately after purchase) and syrups after 3, 6, 9, 12, 15, 18, 21, and 24 months of storage at the abovementioned temperatures were measured. It was observed that the rate of unfavorable changes in chemical composition of starch syrups and the inverted saccharose syrup, mainly the changes in the 5-hydroxymethylfurfural (HMF) content, depended on the type of a syrup and storage conditions (temperature, time). Properties of tested starch syrups intended for winter feeding of bees stored at ca. 20 °C maintained unchanged for up to 6 months, whereas the same syrups stored at lower temperatures (10–14 °C) maintained unchanged physicochemical parameters for about 12 months. In higher temperatures, the HMF content increased. To date, the influence of this compound on bees has not been thoroughly investigated.

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