Effect Of Environmental Temperature Research Articles

Effect of fire and environmental temperature on the reproductive recruitment of Neotropical freshwater turtles

Effect of fire and environmental temperature on the reproductive recruitment of Neotropical freshwater turtles

Effect of environmental temperature and semi‐crystalline order on the toughening of polyamide 1010 by 2D nanomaterials

AbstractBy incorporating nanomaterials into polymer matrices, nanocomposites can be produced with enhanced properties, combining the ease of processing thermoplastics with the superior physical characteristics of nanoparticles. In this study, fully bio‐based polyamide 1010 was used as the polymer matrix, with graphene oxide (GO), hexagonal‐boron nitride (h‐BN), and molybdenum disulfide (MoS2), both individually and in hybrids, serving as fillers. The tensile behavior of these nanocomposites was evaluated at room temperature and −40 °C, along with their morphology and microstructure. Results showed that the nanomaterials slightly shifted the polymer's crystallization temperature upward, indicating a small nucleating effect, but also hindered the development of crystalline domains, reducing the crystallization kinetics. Despite no change in the final crystalline form, nanocomposites with h‐BN and MoS2 showed lower microstructural order as evidenced by XRD. Regarding tensile behavior, GO provided the greatest toughening at room temperature due to its larger lateral dimensions and good chemical affinity with the matrix. However, at low temperatures, h‐BN‐based nanocomposites maintained the toughening effect better than GO‐based ones. This can be attributed to the lower order of the polymer's semi‐crystalline structure promoted by h‐BN, allowing greater energy dissipation. Surprisingly, hybrid fillers did not exhibit synergistic effects, with one nanomaterial hampering the effect of the other. However, SEM analysis indicated that the fracture mechanisms of the nanocomposites remained unchanged from the neat polymer, which makes them interesting options for applications that require desirable mechanical properties at a wide temperature range.Highlights GO showed the best toughening of polyamide 1010 at room temperature. Toughening at room temperature is mainly due to nanomaterials physical traits. Most nanofillers lowered polyamide's overall microstructural order. Toughening at −40 °C is mainly due to lower microstructural order.

Molecular dynamics simulation on de-icing behavior of nanodroplets on amorphous SiO2

Abstract The ice formation and detachment process of nanoscale water droplets on the amorphous SiO2 substrate, which is for simulating the glass of solar panels, is studied in this paper by molecular dynamics simulation methods, considering the effects of environmental temperature, onset of icing time, and parameters of the nanoarray on the ice formation morphology and ice adhesion strength. The results show that the ice adhesion strength is independent of the environmental temperature. The time of icing onset influences the recoil state of droplets, with a larger spreading area leading to higher adhesion strength. The increase in height and decrease in width of the nanocolumns of nanoarray structure leads to an increase in the contact angle of the droplet, causing a reduction in ice adhesion strength, albeit with a slight rise within a certain height range.

Research on the Impact and Parameters of Liquid-Cooling Garment on Thermal Comfort

Liquid-cooling garment (LCG) can alleviate heat stress and improve thermal comfort in high-temperature environments. This study conducted human experiments to assess the impact of the LCG on physiological parameters and subjective evaluations during heat stress. Then, a numerical parametric study was performed to examine the effect of environmental temperature, inlet temperature, and flow rate on LCG performance. The results demonstrate a significant inhibition of physiological parameter escalation compared to the absence of protective measures. Specifically, skin temperature exhibited a reduction ranging from 1.6% to 4.9%, whereas heart and core temperature rise rates experienced respective decreases of 27.5% and 24.2%. Additionally, there was a notable reduction of 20.76% in sweat production. Elevated skin temperature was associated with heightened thermal sensation and diminished thermal comfort. Moreover, applying the LCG resulted in a noteworthy decrease of 28.5% and 14% in the physiological and perceived stress indexes, respectively. Adjusting inlet temperature better reduces skin temperature than flow rate when environmental temperature and labor intensity increase. Lowering inlet water temperature improved LCG performance. An inlet temperature of 20 °C and a flow rate of 500 mL/min were optimal for moderate labor.

Research on improving the efficiency of electricity transmission

A study of ways to modernize the current-carrying part of overhead lines to improve the efficiency of electricity transmission through the use of innovative types of wires was conducted. The technical and economic characteristics of AC, ACCR, and AERO-Z wires were analyzed. The results of the analysis revealed that further improvement of the design of AC wires should be based on new progressive developments that would meet such technical requirements as reliability, survivability and durability; corrosion resistance; high adhesion ability; resistance to vibration during operation under the influence of adverse climatic factors; resistance to environmental temperature effects. As an innovative solution to this issue, high-temperature (ACCR) and specially designed (AERO-Z) wires have been developed in foreign countries. A comparative analysis of the types of wires used in Ukrainian power grids with innovative types of wires used in power grids of foreign countries was performed. The results of the comparison of AC, ACCR, and AERO-Z wires show that the factor that limits the scope of application of ACCR wire, even for spans with extremely high requirements for power transmission characteristics, is its extremely high cost. This is because the technical characteristics of this wire are better than those of AC wire and it has a relatively low cost compared to ACCR wire, and its special design is adapted to adverse climatic conditions that affect the characteristics of electricity transmission.

Mechanical performance analysis of double-block ballastless tracks in intercity railways under temperature and train loads

The coupling effect of environmental temperature and moving train loads significantly impacts the mechanical performance of ballastless tracks on intercity railways. To further explore the thermal performance of double-block ballastless tracks (DBBTs) under complex temperature conditions, an initial test was conducted on a 1/4 geometric scale DBBT model across three temperature scenarios. Following the validation of these experimental results, thermal-mechanical coupling models for two types of DBBTs (unitized and longitudinal) on subgrades with two different boundary constraints were developed. These models aimed to examine their mechanical responses under train speeds ranging from 120 km/h to 200 km/h and their interaction with high daily temperatures. The findings indicate that temperature change rates in the track slab are significantly higher than those in the supporting layer, with the stresses in the limiting groove and supporting layer being the highest and lowest, respectively. The relationship between temperature and stress in the track slab follows a second-order quadratic polynomial. Additionally, measured longitudinal displacement results are smaller than theoretical predictions, especially under dropping temperatures. Furthermore, under all three train speeds, both dynamic stress and displacement are higher in the longitudinal DBBT than in the unitized DBBT. The coupling effect of temperature and moving train loads notably increases the dynamic stress in both types of DBBTs, with a more pronounced effect on the dynamic displacement of the longitudinal DBBT compared to the unitized DBBT.

Effects of temperature and low strain rate on tensile performance of aramid fiber bundle

AbstractIn this research, the effects of ultimate strain rate and environmental temperature on the mechanical performance of the aramid fiber bundles were experimentally investigated. The scanning electron microscope (SEM) and Fourier transform infrared spectroscopy (FTIR) were used to detect the tensile failure mechanism of the aramid fiber bundle. The results indicated that the tensile strength, failure strain, elastic modulus, and toughness of the aramid fiber bundle were sensitive to the strain rate, which was represented as the typical bilinear monotonic relationships. In contrast, the impact of environmental temperature on the four parameters of aramid fiber bundle was more complex. The ultimate strength, failure strain and toughness of aramid fiber bundle increased with the temperature changing from −60 to 30°C, but rapidly decreased from 30 to 90°C. Finally, the dispersion of the mechanical performance was quantitatively analyzed based on the scale and shape parameters obtained from Weibull model.Highlights Tensile tests for aramid fiber bundle under different strain rates and temperatures were conducted. Strain rate and temperature effects on tensile properties of fiber bundle were quantified. Tensile failure mechanism of fiber bundle was analyzed. Dispersion of the mechanical performance was quantitatively analyzed.

Flexibility in thermal requirements: a comparative analysis of the wide-spread lizard genus Sceloporus.

Adaptation or acclimation of thermal requirements to environmental conditions can reduce thermoregulation costs and increase fitness, especially in ectotherms, which rely heavily on environmental temperatures for thermoregulation. Insight into how thermal niches have shaped thermal requirements across evolutionary history may help predict the survival of species during climate change. The lizard genus Sceloporus has a widespread distribution and inhabits an ample variety of habitats. We evaluated the effects of geographical gradients (i.e. elevation and latitude) and local environmental temperatures on thermal requirements (i.e. preferred body temperature, active body temperature in the field, and critical thermal limits) of Sceloporus species using published and field-collected data and performing phylogenetic comparative analyses. To contrast macro- and micro-evolutional patterns, we also performed intra-specific analyses when sufficient reports existed for a species. We found that preferred body temperature increased with elevation, whereas body temperature in the field decreased with elevation and increased with local environmental temperatures. Critical thermal limits were not related to the geographic gradient or environmental temperatures. The apparent lack of relation of thermal requirements to geographic gradient may increase vulnerability to extinction due to climate change. However, local and temporal variations in thermal landscape determine thermoregulation opportunities and may not be well represented by geographic gradient and mean environmental temperatures. Results showed that Sceloporus lizards are excellent thermoregulators, have wide thermal tolerance ranges, and the preferred temperature was labile. Our results suggest that Sceloporus lizards can adjust to different thermal landscapes, highlighting opportunities for continuous survival in changing thermal environments.

Influence of increasing acclimation temperature on growth, digestion, antioxidant capacity, liver transcriptome and intestinal microflora of Ussruri whitefish Coregonus ussuriensis Berg

For effective restoration, conservation of Ussruri whitefish Coregonus ussuriensis Berg and coping with global climate change, effects of environmental temperature on Ussruri whitefish urgently need to be explored. In current study, the effects of different acclimation temperatures on the growth, digestive physiology, antioxidant ability, liver transcriptional responses and intestinal microflora patterns of Ussruri whitefish were investigated. Ussruri whitefish (15.20 g ± 1.23 g) were reared for 42 days under different acclimation temperatures, i.e., 10, 13, 16, 19, 22 and 25 °C, respectively. Result first determined 28 °C as the semi-lethal temperature in order to design the temperature gradient test. Highest main gain rate (MGR) and specific growth rate (SGR) were observed in fish group having acclimation temperature of 19 °C. Significantly decrease (P < 0.05) in triglyceride (TG) content appeared at 19 °C as compared to the 10 °C and 13 °C temperature groups. 19 °C notablely increased protease activities of stomach and intestine and intestinal lipase and amylase activities. 19 °C group obtained the highest activities of chloramphnicol acetyltransferase (CAT) and total antioxidant capacity (T-AOC) and higher activities of superoxide dismutase (SOD). The intestinal microflora composition was most conducive to maintaining overall intestinal health when the temperature was 19 °C, compared to 10 °C and 25 °C. Ussruri whitefish exposed to 10 °C and 25 °C possessed the lower Lactobacillus abundance compared to exposure to 19 °C. Temperature down to 10 °C or up to 25 °C, respectively, triggered cold stress and heat stress, which leading to impairment in intestinal digestion, liver antioxidant capacity and intestinal microflora structure. Liver transcriptome response to 10 °C, 19 °C and 25 °C revealed that Ussruri whitefish might require the initiation of endoplasmic reticulum stress to correct protein damage from cold-temperature and high-temperature stress, and it was speculated that DNAJB11 could be regarded as a biomarker of cold stress response.Based on the quadratic regression analysis of MGR and SGR against temperature, the optimal acclamation temperature were, respectively, 18.0 °C and 18.1 °C. Our findings provide valuable theoretical insights for an in-depth understanding of temperature acclimation mechanisms and laid the foundation for conservation and development of Ussruri whitefish germplasm resources.

Thermal Vibration of Thick FGM Conical Shells by Using Third-Order Shear Deformation Theory.

A time-dependent third-order shear deformation theory (TSDT) approach on the displacements of thick functionally graded material (FGM) conical shells under dynamic thermal vibration is studied. Dynamic equations of motion with TSDT for thick FGM conical shells are applied directly with the partial derivative of variable R*θ in the curve coordinates (x, θ, z) instead of y in the Cartesian coordinates (x, y, z) for thick FGM plates, where R* is the middle-surface radius at any point on conical shells. The generalized differential quadrature (GDQ) numerical method is used to solve the dynamic differential equations in equilibrium matrix forms under thermal loads. It is the novelty of the current study to identify the parametric effects of shear correction coefficient, environment temperature, TSDT model, and FGM power law index on the displacements and stresses in the thick conical shells only subjected to sinusoidal heating loads. The physical parts with values on the length-to-thickness ratio equals 5, and 10 FGMs can be used in an area of an airplane engine that usually operates near more than 1000 K of temperatures when the thermal stress is considered and affected. The important findings of the presented study are listed as follows. The values of normal stress are in decreasing tendencies with time in cases when the coefficient c1 equals 0.925925/mm2 in TSDT and length-to-thickness ratio equals 5. The shear stress values in x plane z direction on the minor middle-surface radius (r) equals the major middle-surface radius (R) over 8 and length-to-thickness ratio equals to 5 can withstand T = 1000 K of pressure.

Assessing responses to heat in a range-shifting, nocturnal, flying squirrel.

Over the last few decades North American flying squirrels (Glaucomys spp.) have experienced dramatic northward range shifts. Previous studies have focused on the potential effects of warming winter temperatures, yet the hypothesis that rising summer temperature had a role in these range shifts remained unexplored. We therefore sought to determine the effect of high environmental temperatures on the thermoregulation and energetics of flying squirrels in an area of the Northeast of North America with a recent species turnover. Unable to find a logistically feasible population of the northern species (Glaucomys sabrinus), we focused on Southern Flying Squirrels (G. volans). Using flow-through respirometry, we measured the relationship between metabolic rate, evaporative water loss, and body temperature at high ambient temperatures. We also measured core body temperature in free-ranging flying squirrels using temperature-sensitive data loggers. We detected no significant increase in metabolic rate up to ambient temperatures as high as 40 °C. However, evaporative water loss increased at temperatures above 36.2 °C. Free-ranging body temperature of flying squirrels followed a circadian pattern with a ~2 °C difference between active and resting phase modal body temperatures. Rest-phase body temperatures were influenced by environmental temperatures with higher resting temperatures observed on days with higher daily maximum ambient temperatures but not to an extent that energy or water costs were significantly increased during rest. We found that, due to a relatively high level of thermal tolerance, high ambient temperatures are unlikely to cause an energetic strain on Southern Flying Squirrels. However, these findings do not preclude negative impacts of high ambient temperatures on the northern species, and these may still play a role in the changing distributions of Glaucomys in North America.

Assessment of biometrics and stress indicators of the adult Village Weaver birds (Ploceus cucullatus) during breeding and post-breeding seasons in Jos, Nigeria

In this era of climate change, some biological conservationists' concerns are based on seasonal studies that highlight how wild birds' physiological fitness are interconnected with the immediate environment to avoid population decline. We investigated how seasonal biometrics correlated to stress parameters of the adult Village Weavers (Ploceus cucullatus) during breeding and post-breeding seasons of the Weaver birds in Amurum Forest Reserve. Specifically, we explored the following objectives: (i) the seasonal number of birds captured; (ii) whether seasonal baseline corticosterone (CORT), packed cell volume (PCV), and heterophil to lymphocytes ratio (H:L) were sex-dependent; (iii) whether H:L ratio varied with baseline (CORT); (iv) whether phenotypic condition (post-breeding moult) and brood patch varied with baseline (CORT) and H:L ratio; and (v) how body biometrics co-varied birds’ seasonal baseline (CORT), (PCV) and (H:L) ratio. Trapping of birds (May–November) coincided with breeding and post-breeding seasons. The birds (n = 53 males, 39 females) were ringed, morphologically assessed (body mass, wing length, moult, brood patch) and blood collected from their brachial vein was used to assess CORT, PCV and H:L ratio. Although our results indicated more male birds trapped during breeding, the multiple analyses of variance (MANOVA) indicated that the seasonal temperature of the trapping sites correlated (P < 0.05) significantly to baseline (CORT). The general linear mixed model analyses (GLMMs) indicated that the baseline (CORT) also correlated significantly to H:L ratio of the male and female birds. However, PCV correlated significantly to body size of the birds (wing length) and not body mass. Haematological parameters such as the baseline CORT and the H:L ratio as indicators of stress in wild birds. Hence, there is the possibility that the Village Weaver birds suffered from seasonally induced stress under the constrained effect of environmental temperature. Hence, future studies should investigate whether the effect observed is also attributable to other passerine species.

Acute heat trauma model in rats, gender-dependent thermoresistance, and screening of potential thermoprotectors

Heat trauma (HT) is an urgent medical and social problem. Heat damage is a widespread effect of the environment on humans, driven by global warming, military conflicts, technological disasters, work in hot environments, and engagement in extreme sports and tourism. The aim of the study: to propose a model of acute HT in rats that does not cause the death of animals, to determine the dependence of thermoresistance on gender, and to compare the effectiveness of the thermoprotective effects of a range of non-steroidal anti-inflammatory drugs (NSAIDs), paracetamol, and glucosamine hydrochloride in this model. Materials and Methods: The experiment was conducted on adult white rats of both genders. Acute HT was modelled by using a specially developed method involving heat exposure to animals at +55 °C for 30 minutes, followed by a recovery period of 60 minutes. Rectal temperature was measured every 15 minutes. The degree of hyperthermia in males and females was determined. The presence and intensity of the thermoprotective effect of glucosamine hydrochloride (G h/ch), diclofenac sodium, acetylsalicylic acid (ASA), nimesulide, etoricoxib, celecoxib, and paracetamol were evaluated through intragastric administration 60 minutes before heat exposure. The results were analyzed using the STATISTICA 12.0 program. Results: It was established that heat exposure at +55 °C for 30 minutes effectively replicates acute HT in rats without causing animal fatalities, adhering to bioethical requirements. Body temperature increases by 10-13 %, characterized as a heat stroke. Occasionally, thermoresistant animals are encountered, where the temperature increase during the first 15 minutes of exposure is less than 1 °C. These animals should not be used for further modelling of heat trauma. Male rats are more sensitive to the effect of high environmental temperatures than females, exhibiting greater hyperthermia (temperature increase of 5.03±0.39°C compared to 3.72±0.22 °C in females, p&lt;0.01). The thermoprotective effect of glucosamine hydrochloride depends on gender, being more pronounced in males. Among the 6 tested COX inhibitors, the most significant thermoprotective effect was observed in the highly selective COX-2 inhibitor celecoxib and the weakly selective central inhibitor paracetamol, warranting in-depth research into their impact on organ and system states following heat trauma, as well as the mechanisms of their thermoprotective action. The thermoprotective effect is not associated with selectivity towards COX (cyclooxygenase): it is not observed in the highly selective COX-2 inhibitor etoricoxib and moderately selective COX-2 inhibitor nimesulide, as well as in non-selective COX inhibitors such as diclofenac sodium and aspirin, which also slows down the recovery of body temperature after heat exposure. Conclusions: A convenient and simple model of acute HT in rats is proposed, demonstrating higher thermosensitivity and a more pronounced thermoprotective effect of glucosamine hydrochloride in males. A significant thermoprotective effect was identified in celecoxib and paracetamol, surpassing other investigated NSAIDs. The mechanism and specific features of this effect require further clarification

Sex-specific effects of environmental temperature during gestation on fluctuating asymmetry in deciduous teeth.

External environmental heat exposure during gestation impacts the physiology of human development in utero, but evidence for these impacts has not yet been explored in dentition. We examined deciduous teeth for fluctuating asymmetry (FA), a measure of developmental instability, together with gestational environmental temperature data drawn from historical weather statistics. We measured dental casts from the longitudinal Burlington Growth Study, representing 172 participants (ages 3-6 years) with health records. FA was calculated from crown dimensions and intercuspal distances that develop during gestation. Multiple regression separated by sex (nfemale = 81) examined the effects of mean temperatures in each trimester, controlling for birth year. In females, increased temperatures during the first trimester are significantly associated with an increase in FA (p = 0.03), specifically during the second and third prenatal months (p = 0.03). There is no relationship between temperature and FA for either sex in the second or third trimesters, when enamel is formed. Dental instability may be sensitive to temperature in the first trimester in females during the scaffolding of crown shape and size in the earliest stages of tooth formation. Sexual dimorphism in growth investment strategies may explain the differences in results between males and females. Using enduring dental characteristics, these results advance our understanding of the effects of temperature on fetal physiology within a discrete period.

Investigation of radiation tolerance of yttria stabilized zirconia in the ballistic collision regime: Effect of grain size and environmental temperature

The irradiation response of yttria-stabilized zirconia, having different grain sizes, subjected to 900 keV iodine ions at room temperature and 1000 K is reported. GIXRD and Raman spectroscopy indicate superior radiation tolerance of the fine-grained samples when compared to their coarse-grained counterparts which is attributed to the abundance of grain boundaries at relatively shorter distances. A reduction in the residual strain is observed in the samples irradiated at 1000 K. This is attributed to the clustering of the irradiation induced point defects thereby resulting in a decrease in their density, but with a corresponding increase in the extended defects density.

Effect of environment temperature on fatigue properties of laminated leather

In this study the influence of environment temperature on the mechanical properties (tensile strength and elasticity modulus at break) of laminated leather and its layers (split leather and microporous polyurethane (PU) Permair film) under fatigue flexing have been investigated. The testing was carried out by changing the temperature from 20 ± 2°C to −20 ± 2°C (number of cycles NC = 105). The experimental results showed that the character of the dependences of tensile strength and elasticity modulus at break on temperature of fatigue environment of both leathers is similar and significantly differ from characters of analogous dependences of microporous PU film. The defects on the surface of laminated leather become clearly visible when the temperature falls to ≤ -10°C.

Thermal deformation monitoring of a highway bridge: combined analysis of geodetic and satellite-based InSAR measurements with structural simulations

Structural Health Monitoring (SHM) of civil engineering structures is experiencing an increasing progress in the last decades. The present work focuses on the static behavior of a highway bridge due to environmental temperature effects. The goal of the present study was to test the applicability of the satellite-based synthetic aperture radar interferometry (InSAR) for deformation monitoring of a large, curved highway bridge and to compare the obtained results with alternative measurement techniques like classical geodesy surveying and with an advanced computer simulation. Such a comparison is quite rare and provides an important insight into the accuracy, efficiency and limitations of the InSAR technique in the context of SHM. Especially interesting was the question whether the InSAR technique is suitable for blind monitoring of a cluster of bridges in the region of interest. The present study shows that a pre-knowledge about each structure can be very important for a reliable interpretation of the InSAR measurement results. The second challenge of the study was to overcome several objective difficulties of combining and comparing quite different monitoring techniques that result from different sampling rates, measurement points and other specific features and sensitivities. Nevertheless, a suitable approach has been developed and implemented in the present study for the InSAR and total station measurements, providing new results and important knowledge about novel SHM techniques.

Quantifying Abdominal Coloration of Worker Honey Bees.

The main drawback in using coloration to identify honey bee subspecies is the lack of knowledge regarding genetic background, subjectivity of coloration grading, and the effect of the environment. The aim of our study was to evaluate the effect of environmental temperature on the abdominal coloration of honey bee workers and to develop a tool for quantifying abdominal coloration. We obtained four frames of honey bee brood from two colonies and incubated them at two different temperatures (30 and 34 °C). One colony had workers exhibiting yellow marks on the abdomen, while the other did not. We collected hatched workers and photographed abdomens. Images were analyzed using custom-written R script to obtain vectors that summarize the coloration over the abdomen length in a single value-coloration index. We used UMAP to reduce the dimensions of the vectors and to develop a classification procedure with the support vector machine method. We tested the effect of brood origin and temperature on coloration index with ANOVA. UMAP did not distinguish individual abdomens according to experimental group. The trained classifier sufficiently separated abdomens incubated at different temperatures. We improved the performance by preprocessing data with UMAP. The differences among the mean coloration index values were not significant between the gray groups incubated at different temperatures nor between the yellow groups. However, the differences between the gray and yellow groups were significant, permitting options for application of our tool and the newly developed coloration index. Our results indicate that the environmental temperature in the selected range during development does not seem to impact honey bee coloration significantly. The developed color-recording protocol and statistical analysis provide useful tools for quantifying abdominal coloration in honey bees.

Uniaxial tensile behavior of half-grouted sleeve connections with concrete cover after exposure to elevated temperatures

This study presents the tensile behavior of a half-grouted sleeve connection (HGSC). A total of 15 prism samples of grout are subjected to a series of tests before and after exposure to various temperatures. A total of 75 eccentric HGSC specimens with a 40 mm concrete cover and 15 central HGSC specimens without a concrete cover were fabricated for uniaxial tensile loading tests. A pseudo-transient heating regimen was applied to HGSC specimens with concrete covers; the specimens were heated to the desired temperature and left there for a duration of 0 min. This study systematically investigates the tensile properties of post-fire HGSC specimens to assess the combined effects of peak environmental temperature (20 °C, 200 °C, 400 °C, 600 °C, 800 °C), concrete cover depth (0 mm, 40 mm), concrete strength grade (C30, C35, C40, C45, C50), and concrete spalling (burst or unburst). The failure mode, load–displacement curves, sleeve strain distribution, and heat transfer are employed to characterize the response of the HGSC specimens, which is subsequently discussed. It is discovered that, although concrete compressive strength plays a minor role, temperature, concrete cover, and explosive spalling significantly influence certain post-fire tensile parameters of the HGSC. Based on the results, there is considerable potential for determining the ultimate tensile force in HGSC specimens with concrete covers and the remaining compressive strength of grout using ultrasonic pulse velocity detection. Furthermore, a comparative accuracy analytical model, incorporating the influence of tangential strain derived from the experimental results, is established based on confinement stress.

Real-Time Tracking of Carbon Dioxide Concentration Using an Optical Microsphere Resonator Sensor.

Whispering gallery mode resonator sensors are nondisruptive optical sensors that can detect and monitor perturbations in a gaseous environment. Through its resonant properties of peak wavelength, amplitude, and quality factor (Q factor), changes in concentration can be quantified within seconds and monitored over days with great stability. In addition, the small footprint, low cost, and high sensitivity are ideal properties for a disposable sensor that can be utilized in extreme environments. The large Q factor of the resonant cavity enables long interaction lengths and amplifies the effect of small changes in the background refractive index, which is detectable in picometer shifts of the resonance wavelength. However, this measurement is susceptible to changes in other environmental factors such as temperature, pressure, and humidity, which manifest on the picometer wavelength scale, reinforcing the need to decouple the variables. In this work, we compare the spectral response of different diameter resonators to carbon dioxide, nitrogen, and its mixtures, observing the spectral shifting and broadening of the cavity resonance near 1550 nm. In addition, the effect of environmental temperature on spectral shifting due to the thermo-optic effect is characterized and quantified. Lastly, the gas concentrations are changed in real time to showcase the tracking and recovery capabilities of the resonator sensor.