A new approach to precise mapping of local temperature fields in submicrometer aqueous volumes

Nanodiamonds hosting temperature-sensing centers constitute a closed thermodynamic system. Such a system prevents direct contact of the temperature sensors with the environment making it an ideal environmental insensitive nanosized thermometer. A new design of a nanodiamond thermometer, based on a 500-nm luminescent nanodiamond embedded into the inner channel of a glass submicron pipette is reported. All-optical detection of temperature, based on spectral changes of the emission of “silicon-vacancy” centers with temperature, is used. We demonstrate the applicability of the thermometric tool to the study of temperature distribution near a local heater, placed in an aqueous medium. The calculated and experimental values of temperatures are shown to coincide within measurement error at gradients up to 20 °C/μm. Until now, temperature measurements on the submicron scale at such high gradients have not been performed. The new thermometric tool opens up unique opportunities to answer the urgent paradigm-shifting questions of cell physiology thermodynamics.

Fuzzy control of temperature and humidity microclimate in closed areas for poultry breeding

This contribution describes the ways of temperature and humidity microclimate control in breeding areas using a fuzzy controller. It is focused on poultry, whereby the most important parameters for optimal breeding are temperature and humidity. The main aim was to evaluate the control process according to control quality in the controller’s steady state and the power consumption of the system. The used control algorithm was designed in the Matlab application, and it was practically verified in a closed thermodynamic system. Practical measurements have shown that with an increasing number of fuzzy controller’s interference rules a better control quality in steady states and lower power consumption of the system is achieved.

ENTROPIC FORCE IN A CLOSED IDEAL GAS

For a closed thermodynamic system of ideal gas, the entropic force is studied in this paper. The results show that the entropic force arises when the entropy is deviated from its equilibrium maximum value by an external force. This entropic force resists the entropy deviation enlarging, and will drive the entropy back to its maximum value if the external forces disappear.

Chemical Reactions at the in Vacuo Au/Inp Interface

ABSTRACTThe reaction between a Au film and an Inp substrate occurs much more readily in vacuo than under an external pressure of an inert ga. At atmospheric pressure, the compounds Au2P3 and the γ intermetallic compound (at times designated Au7In3, Au9In4, or Au2In) are formed at 450 °C and remain fairly stable even when annealed at 500°C for hours. Under ultra-high vacuum conditions, phosphorous readily escapes from the film when a sample is annealed at 300°C for 15 minutes, and the major reaction products are the ψ phase (Au3In2) and another intermetallic compound that is probably AuIn. The presence of an inert gas creates a kinetic barrier for the escape of phosphorous from the surface, and thus Au/InP behaves more like a closed thermodynamic system under pressure than in a vacuum.