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Thermal design is a prerequisite essential to design a satellite. In space environment, it makes it possible for the satellite to survive in extreme hot and cold conditions. In recent years small satellite missions have been developed for many kinds of purposes. The paper describes thermal design for the AIST small spacecraft mission. To calculate thermal environment a detailed thermal mathematical model has been developed using the finite element method and Siemens NX 10.0 software with the integrated module NX Space Systems Thermal Simulation. The analysis carried out with the help of mathematical simulation showed the sufficiency of the passive thermal control system of the AIST small spacecraft. In order to improve thermal radiation couplings between panels a coating with a high emissivity factor was applied on all the inner surfaces. The outer surfaces (except the areas occupied with photovoltaic converters) were coated with aluminum foil. The graphs of changes in temperatures of onboard equipment in the orbital flight phase show that all the parameters meet the requirements of the thermal control system specifications.

Abstract: Understanding the correspondence between ambient temperature and insect development is necessary to forecast insect phenology under novel environments. In the face of climate change, both conservation and pest control efforts require accurate phenological predictions. Here, we compare a suite of degree‐day models to assess their ability to predict the phenology of a common, oligophagous butterfly, the silver‐spotted skipper, Epargyreus clarus (Cramer) (Lepidoptera: Hesperiidae). To estimate model parameters, we used development time of eggs and larvae reared in the laboratory at six constant temperatures ranging from 8 to 38 °C and on two host plants of contrasting quality (kudzu and wisteria). We employed three approaches to determine the base temperature to calculate degree days: linear regression, modified reduced major axis regression, and application of a generic base temperature value of 10 °C, which is commonly used in the absence of laboratory data. To calculate the number of degree days required to complete a developmental stage, we used data from caterpillars feeding on high‐ and low‐quality hosts, both in the field and in the laboratory. To test model accuracy, we predicted development time of seven generations of larvae reared in the field on the same host plants across 3 years (2014–2016). To compare performance among models, we regressed predicted vs. observed development time, and found that r2 values were significantly larger when accounting for host plant quality. The accuracy of development time predictions varied across the season, with estimates of the first two generations being more accurate than estimates of the third generation, when ambient temperatures dropped outside the range in which development rate and temperature have a linear relationship. Overall, we show that accounting for variation in host plant quality when calculating development time in the field is more important than the choice of the base temperature for calculating degree days. [ABSTRACT FROM AUTHOR]

Ambient temperature is an especially important factor associated with the development and survival of ectotherms. To minimize the effect of temperature variation, ectotherms have developed specific physiological and biochemical adaptations. Heat shock proteins and other molecular chaperones play specific physiological roles in such thermal adaptation. Here, we analyzed heat shock protein 70 (Hsp70) expression in six lizard species to investigate the variation in Hsp70 response contributing to thermal adaptation. At first, we collected three lizard species of the genus Takydromus from different geographical locations. We found that either the constitutive expression pattern in different organs or the inducible expression pattern under higher ambient temperature were the same. The expression of Hsp70 was higher in the muscles. In liver, Hsp70 expression significantly increased after 38°C heat shock. We then collected other three lizard species, Plestiodon chinensis, Sphenomorphus indicus, and Scincella modesta, from geographical locations near each other, but with different microhabitats. We observed considerable variation in Hsp70 expression; the constitutive Hsp70 expression varied between organs and between species under heat shock. P. chinensis began to express Hsp70 significantly at 39°C and with the maximum expression at 41°C. S. indicus and S. modesta began to express Hsp70 significantly at 35°C, and a temperature above 37°C resulted in fatality for some individuals. Taken together, these results indicated that both microhabitat and active temperature range contributed to the differences in Hsp70 expression in lizards at normal and elevated ambient temperatures. [ABSTRACT FROM AUTHOR]

In the present work, the graphene oxide/blue phase liquid crystal composites and long aminoalkyl chains functionalized graphene/blue phase liquid crystal composites were prepared by doping the additives into a blue phase exhibiting liquid crystal host. It is found that the blue phase temperature range could be widened by dispersing a small amount of functionalized graphene. It suggests that anisotropic two-dimensional flake nanoparticles may be of great usefulness for stabilizing blue phases. [ABSTRACT FROM AUTHOR]

A room temperature curable heat-resistant adhesive with broad working temperature range was prepared through organic and inorganic modification. The preceramic polymethylsiloxane showed low bonding strength for silicon carbide from 400 °C to 600 °C because of the decomposition of polymer network. So the modification with epoxy resin was used to generate strong blending and copolymerization network which decomposed at higher temperature over 500 °C. The ceramization of active fillers and preceramic polymer compensated the bonding strength with rising temperature, thus eliminating the weak stage from 400 °C to 600 °C. The modification with fillers greatly improved its bonding strength at high temperature over 1000 °C. Consequently, the modified adhesive exhibited outstanding bonding strength tested at room temperature between 9.29 ± 0.56 MPa and 37.28 ± 1.33 MPa after heat-treatment from 25 °C to 1500 °C and the bonding strength directly tested at the temperature from 25 °C to 800 °C over 8.21 ± 0.40 MPa. The adhesive shows the potential to extend the application for engineering ceramic joining. [ABSTRACT FROM AUTHOR]

Thermal behavior of electronic equipment is the determining factor for performing rapid assessment of the effectiveness of design and operation of the equipment. The assessment method proposed in this article consists in fixation of an infrared video stream from the surface of the device and converting it into a visible flow by means of a thermal imager, splitting it into component colors and their further processing using parabolic transformation. The result of the transformation is the number used as a rapid criterion for estimation of distribution stability of heat in the equipment.