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Four Polyanilines (PANI) doped with different acids (HCl, dodecylbenzene sulfonic acid or DBSA and sodio-5-sulfoisophtalic acid or NaSIPA) have been prepared by chemical oxidative polymerization, through direct and indirect routes of synthesis. The synthesis conditions have been optimized to be simple, low-cost and transferable to industrial processing. The PANIs have been characterized by Transmission electron microscopy (TEM), Fourier transform infrared spectroscopy (FTIR), thermogravimetric analysis (TGA) and electrical DC conductivity. The nature of the acid dopant and synthetic conditions affect the doping level, oxidation state, presence of oligomeric chains and morphology, which account for the conductivity values spanning from 3.9 to 14.7 S/cm. The polymers were subjected to different heating ramps and heating-cooling cycles to test the dependence of electrical conductivity with temperature. Conductivity retention upon heating is affected by moisture content, thermal stability of the dopant, strength of the PANI-acid complex and rearrangement capability of both PANI and organic dopant alkyl chains. Two DBSA doped PANIs, obtained by direct and indirect methods, exhibit the best conductivity retention up to 150 ºC and excellent thermo-resistive properties in cyclic experiments, which make them potential materials for thermal sensor applications., Authors acknowledge the financial support to Xunta de Galicia-FEDER (Program of Consolidation and structuring competitive research units (GRC2014/036)) and the FCTFundação para a Ciência e a Tecnologia for financial support under projects PTDC/EEISII/5582/2014 and PTDC/CTM-ENE/5387/2014. Financial support from the Basque Government Industry Department under the ELKARTEK Program is also acknowledged. SLM thanks the Diputación Foral de Bizkaia for financial support under the Bizkaia Talent program; European Union’s Seventh Framework Programme; Marie Curie Actions – People; Grant agreement nº 267230., info:eu-repo/semantics/publishedVersion

This chapter deals with the use of thermal protection materials for two key components of a solid rocket motor (SRM): the exhaust nozzle and internal motor insulation. The role of the materials utilized for SRM thermal protection depends on the engineers involved, who would ideally be using data obtained from full-scale ground or in-flight testing to help guide their choices. Three important research areas are discussed in this chapter: (1) advanced polymer nanocomposite (PNC) ablatives: PNCs for SRM nozzles and PNCs for SRM internal insulation, (2) new sensing technology: in situ ablation recession and thermal sensor, and char strength sensor, and (3) technologies needed to advance PNC ablative research: thermophysical properties characterization and ablation modeling.

The thermal infrared spectrum of the Earth as observed from space contains a wealth of information regarding the chemical composition and temperature of the atmosphere and surface. The wavelength range referred to by the term “thermal infrared” spans more than two orders of magnitude, and specialized materials and techniques are required to develop sensors that operate effectively in this spectral region. This article provides an introduction to the components used in thermal sensors, an overview of basic sensor design and operation concepts, and a discussion of instrument calibration.

Food industry is currently using thermal imaging to measure temperature of fresh produce, but there is no comparative study between temperatures measured traditionally by temperature probes and the temperatures measured by thermal imaging reported in the literature. This paper is exploring the possibility to use surface temperature measured by infrared (IR) thermal imaging versus temperatures measured by a network of temperature sensors. Two different types of vegetables (chard and cucumber) were covered with three different types of covers (Tyvek material, Metalized PET and Metalized PET with bubble wrap layer) which are designed to protect shipments of produce against temperature abuses. Each cover/produce combination was exposed to a temperature warm up regime in order to simulate a break in the cold chain during distribution, and it was monitored with the thermal IR camera and temperature sensors for comparisons. Results of temperature measured by thermal imaging showed a differential between 1.9 and 6 °C compared to temperature measured by thermal sensors. These found differences are unacceptable for fresh produce temperature control. The high emissivity of metalized PET produced significant reading errors when using the IR camera. Tyvek cover had more consistent results due to a higher emissivity value that is closer to the value used by the IR camera. This study is of great value since it is giving instructions of how the thermal camera should be used for temperature measurements for covered pallets., The authors would like to express their thanks for the help of Jose Luis Pellon Gonzalez, and the Laboratory of Refrigeration, in the ETSIAAB (School of Agricultural, Food and Biosystems Engineering). Also, we would like to thank the farmers of Villa del Prado (Madrid) for providing the cucumbers, and the Agricultural Research Center of Marchamalo (Guadalajara) for providing the chard.

Coal fires occur in nearly all coal producing countries around the world. This chapter addresses mapping techniques to assess the fire situations in coal bearing areas, and discusses the harmful consequences of the fires, which release a vast amount of greenhouse gases to the atmosphere. Concerning the large area mapping of coal fires, Earth observation by satellites has proven to be a powerful tool to support the delineation of coal fire risk areas, the detection of coal fire related hot spots, as well as the quantification of the coal fires. Satellites such as Landsat-TM, Landsat ETM+, as well as the novel Landsat DCM all have thermal sensors(spatial resolutions of 120m, 60m, and 100m), allowing for the mapping of the Earth’s temperature from space—during the daytime, as well as during the night-time. But also thermal bands of lower spatial resolution sensors such as MODIS and AVHRR (500m to 1km) have proven suitable for the general assessment of temperature patterns in a coal fire affected region. This chapter presents satellite image processing techniques to detect coal fire related thermal anomalies in such Earth observation data. Furthermore, methods for coal fire risk area delineation and coal fire quantification—both also based on satellite image analyses—are introduced. As all space-borne mapping needs to be validated on the ground coal fire in situ mapping techniques and the coal fire dynamics of some of the largest coal fire regions in China and India are presented. The chapter closes with a discussion on current advances and challenges in coal fire-related greenhouse gas emission estimation.

The detection of environmental temperature is critical for the survival of the most diverse organisms. Thermosensitive transient receptor potential (thermoTRP) channels have evolved as a class of ion channels activated by a wide range of temperatures. These molecular thermal sensors are spread through the different TRP channel subfamilies. Among the Melastatin subfamily of TRP channels, the eighth member, TRPM8, is a calcium-permeable cationic ion channel activated by cold, by substances that evoke cold sensation such as menthol, and by voltage. This channel is considered the main molecular entity responsible for the sensitivity to cold of primary sensory neurons of the somatosensory system. Here we present to the readers a summary of some the most relevant biophysical properties, physiological role, and molecular intimacies of this polymodal thermoTRP channel.

Shape memory alloy springs have been applied as sensors and actuators in various applications in combination with bias springs since they respond and generate force at the same time by temperature change. The shape memory spring actuator can also save weight and space and reduce the number of parts needed, such as a sequencer, a motor, a sensor and a power supply that are required for conventional actuators. Various ideas for the application of shape memory actuators have been suggested from home electronics and materials makers and some of them have been successfully commercialized. This chapter introduces commercial productions using shape memory actuators in household appliances and electrical equipment.

Publisher Summary This chapter reviews some of the major concepts and mechanisms used to investigate, characterize, assess, and enhance the performance of total protective clothing (TPC) in extremely hot or fire-prone environments. First, the major fabric materials used as outer shells for TPC are reviewed, and then the various stages of the exposure process are described. The major testing methods, evaluation tools, and computing models are also discussed, including the associated thermal sensors and burn damage evaluation schemes. Heat effects on the dermal layers of the skin and the modeling of human skin burn injuries is presented. There is no extensive numerical/empirical modeling of thermal mechanisms in TPC when exposed to intense heat sources because of its complexity. Most of the existing models are based on simplified, steady state, one-dimensional heat transfer processes that can be assessed in a bench-top thermal protective performance (TPP) evaluation environment. A calorimeter- type sensor, such as the TPP sensor, which tracks the heat flux trough the TPC fabric, has a copper disk of a considerable size that disturb the thermal balance during heat flux measurement.