Catalogue Search | MBRL
Are you sure you want to remove the book from the shelf?
{{itemTitle}}
50,935
result(s) for
"Infrared radiation"
Sort by:
Water Saturation Effects on Thermal Infrared Radiation Features of Rock Materials During Deformation and Fracturing
This paper aims to investigate the water saturation effects on the thermal infrared radiation (IRR) characteristics of rock materials during deformation and fracturing processes. Three kinds of rocks, namely sandstone, granite, and marble, were adopted for tests. Uniaxial compression tests were carried out on oven-dried and water-saturated rock samples. The evolution of IRR temperature on rock surface was monitored and recorded with the aid of an infrared thermographic camera. Test results show that the IRR temperature of saturated samples is apparently higher than that of dry ones subjected to the same axial stress. After water saturation, the heating rate in elastic deformation phase, the IRR temperature increment at peak stress, and the IRR temperature on the new-formed fracture surface have a significant growth compared to dry condition. These indicate that the presence of water facilitates the release of thermal energy. The sensitivities of the heating rates in elastic deformation phase to water saturation are very distinct for the three rocks. This is possibly resulted from the mineral composition of rock types, especially the proportion of calcite and swelling clay minerals. The IRR temperature increment at peak stress for rock not only depends on the moisture condition, but is also relevant to the uniaxial compressive strength.
Journal Article
Characteristics of Infrared Radiation of Coal Specimens Under Uniaxial Loading
An object in its natural state at temperatures greater than -273.15 C generates electromagnetic waves, including infrared radiation (Wu et al. 2000). Coal and rock under loading also produce detectable electromagnetic radiation anomalies including wavelengths in the infrared band (Brady and Rowell 1986; Luong 1987). Through studying the infrared radiation characteristics on the surface of coal and rock specimens under loading conditions, one can derive the relationship between infrared radiation and the mechanical parameters of the specimens under dynamic stress. This information can be used to predict dynamic phenomena including ground pressure, coal bursting, and rock bursting.
Journal Article
Earth's Long-Wave Infrared: Review and Study of Scalable Applications
The Earth's infrared energy storage is substantial, and its large-scale utilization could effectively ameliorate the greenhouse effect on Earth. Several applications of utilizing Earth's infrared radiation for cooling and power generation are summarized based on existing literature. Building upon this foundation, the use of water as an excellent energy storage medium is proposed, and a long-wave energy storage system is designed. This system can harness the immense energy density of long-wave infrared radiation with fixed bandwidth or wavelength. A comprehensive study on large-scale application is outlined in four aspects, leveraging the energy storage and radiation advantages of the system: (a) Long-wave infrared is efficiently transported using hollow glass infrared fibers for room cooling and heating. This addresses the issues of separate terminals for capillary radiation air conditioning, high costs, and maintenance challenges. (b) Building on existing literature, taking Hainan as an example, the utilization of a temperature difference of approximately 15 °C between the lowest and highest temperatures in a day for power generation is suggested. (c) The composition and structure of planar antennas are derived, and parameter selection for rectifying diodes is proposed based on radiation fluctuation theory and antenna theory. This lays a theoretical and practical foundation for converting long-wave radiation waves using rectifying antennas. (d) The long-wave radiation quantum theory is utilized to propose the concept of manufacturing components that can directly convert energy from long-wave radiation. In each of these four aspects of large-scale utilization, the emphasis is on water's excellent insulation, storage, and radiation properties, presenting new perspectives for the widespread utilization of Earth's infrared and offering a quick pathway for humanity to explore new energy sources and mitigate the greenhouse effect on Earth, facilitating a harmonious coexistence between humans and nature.
Journal Article
Far infrared properties of OH megamaser host galaxies
The hosts of OH megamaser (OHM) are luminous infrared galaxies (LIRGs), in fact 1/3 of them are ultra-luminous infrared galaxies (ULIRGs), which imply that OHM phenomena should be related to the infrared radiation field. In this paper, we investigate the far infrared (FIR) properties of OHM host galaxies, through detailed infrared data covering broad bands. All known OHM sources and one control sample of (U)LIRGs without maser detections (non-OHM sources) are cross-identified with AKARI and Herschel photometric catalogs. Comparative analysis on the spectral energy distribution (SED) with broad coverage from
J
to 350
μ
m (taken from 2MASS, WISE, Spitzer, and AKARI and Herschel archive data) shows that the OHM sources tend to have higher FIR luminosities than those of the non-OHM sources, which are more pronounced in the SED range covered by the AKARI. These are consistent with our statistical results of the FIR luminosities distribution of both the samples, which show that the OHM sources tend to have higher FIR luminosities, especially, at short FIR wavelength (i.e., the 65 and 90
μ
m). However, the non-OHM sources tend to have much stronger emission than those of OHM sources at both the near infrared (NIR) and middle infrared (MIR) bands. The statistic analysis of the color–color properties at MIR and FIR bands shows that the OHM sources have much cooler MIR and warmer FIR colors than non-OHM sources. These clues could help us to choose OHM candidates for future OHM surveys with the Five-hundred-meter Aperture Spherical radio Telescope (FAST), where the OHM detection rate may exceed 40%. Further, one significant correlation of
L
OH
∝
L
T
FIR
1.18
±
0.11
can be found between the maser luminosity and total FIR luminosity of OHM LIRGs. Combined with previous studies, we suggest that the OHM is dominantly pumped by the FIR, instead of NIR and MIR radiation fields.
Journal Article
An ultrahot gas-giant exoplanet with a stratosphere
Observations of the gas-giant exoplanet WASP-121b reveal near-infrared emission lines of water, suggesting that the planet has a stratosphere—a layer in the upper atmosphere where temperature increases with altitude.
An exoplanet with a stratosphere
Earth's atmosphere consists of layers that are partially defined by their temperature. In the troposphere, which is just above the Earth's surface, temperature decreases with altitude, whereas the layer above, the stratosphere, is warmer. Exoplanets could also have stratospheres, but whether they actually do has been an open question. One way to find out is to observe whether molecular species are seen in emission in the planet's thermal spectrum, which would indicate that the overlying layer is hotter than the lower one. Tom Evans
et al
. report observations of the gas-giant exoplanet WASP-121b, which reveal emission lines of water, from which they conclude that the planet has a stratosphere.
Infrared radiation emitted from a planet contains information about the chemical composition and vertical temperature profile of its atmosphere
1
,
2
,
3
. If upper layers are cooler than lower layers, molecular gases will produce absorption features in the planetary thermal spectrum
4
,
5
. Conversely, if there is a stratosphere—where temperature increases with altitude—these molecular features will be observed in emission
6
,
7
,
8
. It has been suggested that stratospheres could form in highly irradiated exoplanets
9
,
10
, but the extent to which this occurs is unresolved both theoretically
11
,
12
and observationally
3
,
13
,
14
,
15
. A previous claim for the presence of a stratosphere
14
remains open to question, owing to the challenges posed by the highly variable host star and the low spectral resolution of the measurements
3
. Here we report a near-infrared thermal spectrum for the ultrahot gas giant WASP-121b, which has an equilibrium temperature of approximately 2,500 kelvin. Water is resolved in emission, providing a detection of an exoplanet stratosphere at 5
σ
confidence. These observations imply that a substantial fraction of incident stellar radiation is retained at high altitudes in the atmosphere, possibly by absorbing chemical species such as gaseous vanadium oxide and titanium oxide.
Journal Article
Analysis of tiles produced from a schist material and their ultraviolet, near-infrared, mid-infrared, longwave-infrared and far-infrared spectra
Clays are used in the general production of earthen tiles. In this study, the production and characterization of earthen tiles from schist, a clayey rock formed by metamorphism of mudstone or shale, was investigated. The impact of tiles on atmospheric temperature through their absorption of the visible, near-infrared and far-infrared wavelength regions is evaluated. In particular, the absorption of ultraviolet and infrared radiation by the tiles was evaluated, as this could have beneficial applications for human health and the environment. UV-A radiation (320–400 nm) is not absorbed by the atmosphere, but schist materials absorb UV-A, which can contribute to melanoma formation (i.e. cancer). Field-emission scanning electron microscopy, X-ray fluorescence spectrometry and X-ray diffraction were used for the analysis of the schist materials. The tile-production stages of schist materials (drying, firing, water absorption rate, etc.) were tested at Hatipoglu Gunes Tile and Brick Industry, Inc. (Turkey). The tiles fired at 950°C and 1000°C comply with the industry standard compressive strength values for fired tiles (when converted to industry production conditions) and were 156.15 and 123.20 kg cm –2 , respectively.
Journal Article
Characterization of connective tissues using near-infrared spectroscopy and imaging
Near-infrared (NIR) spectroscopy is a powerful analytical method for rapid, non-destructive and label-free assessment of biological materials. Compared to mid-infrared spectroscopy, NIR spectroscopy excels in penetration depth, allowing intact biological tissue assessment, albeit at the cost of reduced molecular specificity. Furthermore, it is relatively safe compared to Raman spectroscopy, with no risk of laser-induced photothermal damage. A typical NIR spectroscopy workflow for biological tissue characterization involves sample preparation, spectral acquisition, pre-processing and analysis. The resulting spectrum embeds intrinsic information on the tissue’s biomolecular, structural and functional properties. Here we demonstrate the analytical power of NIR spectroscopy for exploratory and diagnostic applications by providing instructions for acquiring NIR spectra, maps and images in biological tissues. By adapting and extending this protocol from the demonstrated application in connective tissues to other biological tissues, we expect that a typical NIR spectroscopic study can be performed by a non-specialist user to characterize biological tissues in basic research or clinical settings. We also describe how to use this protocol for exploratory study on connective tissues, including differentiating among ligament types, non-destructively monitoring changes in matrix formation during engineered cartilage development, mapping articular cartilage proteoglycan content across bovine patella and spectral imaging across the depth-wise zones of articular cartilage and subchondral bone. Depending on acquisition mode and experiment objectives, a typical exploratory study can be completed within 6 h, including sample preparation and data analysis.
This protocol describes how to perform near-infrared spectroscopy and imaging of connective tissues. Detailed guidelines are provided for sample preparation, spectral acquisition and data pre-processing and analysis, with example applications.
Journal Article
Effects of far-infrared radiation temperature on drying characteristics, water status, microstructure and quality of kiwifruit slices
Far-infrared radiation (FIR) drying is an advanced technique that has recently been applied in food processing. In order to reveal the effects of FIR temperature on dehydration process and quality characteristics of kiwifruit slices, FIR drying experiments on kiwifruit slices were conducted. Low-field nuclear magnetic resonance, scanning electron microscopy, colorimeter and chemical analysis were applied to explore the dynamic water states, microstructure, color changes and nutritional components of kiwifruit slices at different FIR temperatures. The results showed that drying time reduced by 57.9% and average drying rate increased by 137.5% as FIR temperature increased from 120 to 280 °C. The water mobility and distribution in kiwifruits changed with the extension of drying time, and increasing FIR temperature could accelerate the migration and removal of moisture. Higher FIR temperature could produce more cavities and larger channels in dried samples. An increase in FIR temperature decreased
L
*
but increased
a
*
values of dried kiwifruits and affected total phenolic content, total flavonoids content and Vitamin C content. Therefore, FIR drying is a promising method to improve drying rate as well as protect product quality of kiwifruit slices.
Journal Article
Gender-Related Effect in Oxygenation Dynamics by Using Far-Infrared Intervention with Near-Infrared Spectroscopy Measurement: A Gender Differences Controlled Trial
Many studies have indicated the microcirculation can directly respond to disease-related symptoms. However, the capacity of microcirculation would vary due to the gender differences. Near-infrared spectroscopy (NIRS) is a noninvasive technique to monitor tissue oxygenation dynamics. In this study, the far-infrared (FIR) source was used for physiological intervention of microcirculation. The experimental results show that the nature difference of oxygenation status exists between male and female during FIR irradiation. Therefore, we suggest the NIRS-based assessment should be calibrated with the gender-related effect for clinical diagnosis of peripheral arterial disease.
Journal Article