ΔT Values Research Articles

Isotope shift measurements in 555-833 nm wavelength region with FTS and electronic configuration assignments to the energy levels of neutral dysprosium atom

Precise spectroscopic measurements of isotope shift (IS), Δσ (160Dy - 164Dy) have been carried out in the 258 atomic emission lines of neutral dysprosium covering 555–833 nm wavelength region, of which IS data for 198 lines is being reported for the first time. The present measurements have contributed significantly to understanding the complex Dy I atomic structure, which enabled us to report the level isotope shift, ΔT (160Dy - 164Dy) for 100 even- parity and 82 odd- parity energy levels out of which ΔT (160Dy - 164Dy) values for 45 even- and 36 odd- parity levels are new. Earlier tentative assignments of 15 even levels to 4f95d6s6p and 5 even- levels to 4f106s6d configuration have been confirmed in the present study. New configuration assignments have been made to 10 even levels and also 5 each assigned to 4f95d6s6p and 4f106s6d configurations. The validity of 10 odd-parity energy levels theoretically assigned earlier to the mixed (4f95d6s2+4f106s6p+4f95d26s) configurations has been verified using newly derived experimental level isotope shifts, ΔT (160Dy-164Dy) values. Tentative assignments of 4f105d6p configuration confirmed for the 5 odd levels lying between 35029.50 cm−1 (J=8) - 37836.50 cm−1 (J=9). The present investigations have led to the first identification of two almost pure levels of 4f105d6p configuration at 35777.79 cm−1 (J=8) and 36260.17 cm−1 (J=9). The ΔT (160Dy- 164Dy) values for 2 levels of 4f106s7p configuration have been evaluated by us for the first time, whose configuration assignments have been confirmed presently.

Gellan‐Gum and LiTFSI‐Based Solid Polymer Electrolytes for Electrochromic Devices

AbstractIt has been long recognized that solid polymer electrolytes (SPEs) are potentially interesting for solid‐state electrochemical devices. Gellan gum (Ge)‐based SPEs, plasticized with glycerol (Gly) and doped with lithium bis(trifluoromethanesulfone)imide (LiTFSI) were prepared by the solvent casting technique, and their properties were evaluated. LiTFSI‐based SPE systems exhibit, on the average, higher conductivities than similar systems with other lithium salts. The structure, morphology, complex impedance spectroscopy, cyclic voltammetry and thermal stability of the new electrolyte system were characterized. Electrochromic devices (ECDs) were built with optimized electrolyte samples and their performance was analyzed. The samples were applied in small ECDs with glass/ITO/CeO2‐TiO2/SPE/Prussian blue/ITO/glass configuration. The devices presented a two‐modulation operation: a semi‐bright mode (−2.5 V) and a dark mode (+0.5 V). The best results were obtained with the ECD containing the GeGly1Li2.4 electrolyte, for which the transmittance (T) values in the bleached and colored states were ca. 33.4/43.0 % and 5.4/8.8 % at 555/1000 nm, respectively. These results correspond to ΔT and ΔOD values of 28.0/34.2 % and 0.79/0.69, respectively, which give quite high CEin and CEout values of −4925 cm2 C−1 for bleaching (Qin=−272.1 μC cm−2), and 2062 cm2 C−1 for coloring (Qout=650.0 μC cm−2), at 630 nm. This electro‐optical performance suggests that the proposed SPE systems are promising materials to be further investigated and applied in ECDs.

Seismic anisotropy accrued by seven unusually deep local earthquakes (between 50 and 60 km) in the Albertine Rift: implications of asthenospheric melt upwelling

We investigated the primary mechanisms triggering the S-wave splitting (SWS) of seven unusually deep local earthquakes (between 50 and 60 km) which originated in the lithosphere beneath the Rwenzori region. We attempted to develop an understanding of the relationship between anisotropic structures in the lithosphere and tectonic deformation processes. A total of 12 out of 44 waveforms showed evidence of SWS on their polarization diagrams. The fast-wave direction (φ) and delay-time (δt) were estimated using the covariance matrix and the cross-correlation coefficient methods, respectively. We observed a clockwise rotation of φ-directions (NW - SE and ~ENE - WSW) at stations located in the rift valley. We related this pattern of φ-directions to anisotropic fabric, probably lattice-preferred orientation of preexisting olivine, whose a-axes are aligned with ESE absolute plate motion (APM) vector. At stations located outside the rift valley, however, we observed WNW - ESE and NNW - SSE patterns of φ-directions. We associated these patterns to the shape-preferred orientation of structures frozen in the lithosphere that are aligned with the present-day APM direction. We observed δt values ranging between 0.04 ± 0.01s and 0.43 ± 0.02 s, which decrease with distance away from the rift axis. This further supported our concept that the anisotropy observed at stations located on the moving plate is related to aligned melt inclusions frozen in the surrounding lithosphere. We further observed that the δt values increase linearly with ray-path length, which could indicate a fairly uniform anisotropy between 50-km and 60-km depth. Our study reported no evidence of multi-layer anisotropy beneath the Rwenzori region.

A new method to measure the three-dimensional solubility parameters of acrylate rubber and predict its oil resistance

As people pay more and more attention to environmental protection and the high cost of diesel and gasoline, in order to reduce environmental pollution and use cost, some low-pollution and low-cost components, such as alcohols (ethanol, etc.) and esters (methyl acetate, etc.), are added to diesel and gasoline. Due to the addition of new components, the swelling degree of rubber products will also change. In the literature, this method is often used to test the oil resistance of vulcanizates directly by immersing them in oil. In this paper, a new method is used to predict the oil resistance of vulcanizates. In order to investigate the swelling property of acrylate rubber more comprehensively and predict its oil resistance, the swelling behavior of carboxylic acrylate rubber (AR12) produced by Zeon Corporation (Japan) was measured by swelling method in 24 different organic solvents, and the value of one-dimensional solubility parameter (δ) of AR12 was obtained, ranging from 18 to 22 MPa1/2. The swelling data were analyzed by Hansen Solubility Parameter in Practice software, and the three-dimensional solubility parameter sphere, two-dimensional solubility parameter graph and three-dimensional solubility parameter of AR12 were thus obtained. The values of the three-dimensional solubility parameter of AR12 were δd = 18.30 MPa1/2, δp = 7.10 MPa1/2 and δh = 5.60 MPa1/2, respectively. There is an energy difference (Ra) between AR12 and the 24 solvents, and the swelling ratio (q) of AR12 in the 24 solvents presents an inverse “S”-shaped curve as the Ra values between them change. The experimental results proved that the three-dimensional solubility parameters were more accurate in predicting swelling performance than that of one-dimensional solubility parameter. To verify the experimental results, the relationships of Ra, q and δt values with the volume fractions of two groups of solvent mixtures were established. The experimental results showed the same as those obtained by a single solvent, which further proved the correlation of rubber swelling responses. This new method can be used to predict the oil resistance of rubber, and its advantages compared to traditional methods are using more environmentally friendly and cheaper liquid instead of toxic or expensive liquid. This method can be used not only to evaluate acrylate rubber, but also predict the oil resistance of other polymers.

Experimental investigation of airflow pattern and turbulence characteristics of stratum ventilation in heating mode

Stratum ventilation (SV) is feasible for heating applications. Owing to the downward supply vane angle and positive thermal buoyancy, the airflow characteristics of SV for winter heating can be distinct from those for summer cooling. This study aimed to investigate the airflow pattern and turbulence characteristics in a field environment chamber heated by SV experimentally. Twelve cases were studied with the room air temperature controlled between 19.9 and 24.3 °C. Air velocities and temperatures in the occupied zone were measured. Based on the measurements, draft risk (DR) and vertical air temperature difference between head and ankle levels (ΔT) were evaluated. The results show that the warm supply air jets were initially delivered to the zone below 1.1 m, but gradually ascended to the upper zone owing to the effect of positive thermal buoyancy. Consequently, the heights where the highest air velocity and temperature were measured varied with the distance from the supply inlets. As a result of the airflow pattern, the re-separation phenomenon of velocity spectra at different heights was observed at the far field from the inlets. These characteristics were different from those of SV for summer cooling. The airflow pattern illustrated that SV could warm the occupied zone efficiently, especially when the Archimedes number was less than 0.045. An appropriate reduction in the supply air temperature is recommended to achieve satisfactory local thermal comfort with ΔT and DR values conforming to the comfortable ranges as stipulated in ISO 7730–2005.

Optimization of Ranque–Hilsch vortex tube performances via Taguchi method

In this study, by considering the changes in inlet pressures, connection nozzle materials and the number of orifices, the performances of Ranque–Hilsch vortex tubes (RHVTs) were modelled by multiple linear regression method at which carbon dioxide (CO2) was used as compressed fluid, and optimum operating conditions were tried to be determined by Taguchi method. In the experiment, counterflow RHVTs having O10 mm inner diameter and 100 mm body length were used, hot fluid outlet of which was left completely open. In the tests designed using Taguchi L16 mix type (8 × 1 2 × 3) orthogonal array, 8 different inlet pressures (200, 250, 300, 350, 400, 450, 500 and 550 kPa), 2 different types of connections (parallel and series), 2 different types of nozzle materials (brass and polyamide) and 2 different numbers of orifices (4 and 6) were chosen as control factors and levels. Maximum temperature gradient (∆T) was determined as quality characteristics, and RHVT’s performance tests were done. In order to determine the effect rates of selected control factors on quality characteristics (∆T), analysis of variance (ANOVA) was applied within 95% confidence level. According to the statistical results, it was determined that ΔT values were mostly influenced by the inlet pressure and this was followed by connection type, number of orifices and nozzle material. With the confirmation test performed, reliability of the optimization was tested and confirmed.

Evaluation and Optimization of O2 Used Ranque-Hilsch Vortex Tube Performance

ABSTRACT Ranque-Hilsch Vortex Tube (RHVT) is a mechanic system which can make heating and cooling by using basic heat transfer laws with a compressed fluid. Environmental friendly RHVT is widely used in cooling systems in medicine, electronics, and computer sectors, particularly in the food sector. In this study, the performances of parallel RHVTs in which oxygen (O2) gas is used were reviewed considering different inlet pressures, nozzle materials and orifice numbers. Test results were modeled by multiple linear regression method and regression equation was derived. Besides, Signal/Noise (S/N) ratios of the designed test results were calculated using Taguchi L16 mix type (4 × 2 2 × 1) orthogonal sequence, and optimum conditions were determined. Throughout the test, hot fluid outlet valve of the counter flow RHVTs having Ø10 mm inner diameter and 100 mm body length was completely left open. As control factors and levels, four different inlet pressures (200, 350, 500, and 650 kPa), four different number of orifices (three, four, five, and six), and two different nozzle materials (brass and polyamide) were selected. For quality characteristics, maximum temperature gradient (∆T) was determined. In order to determine the effect rates of the control factors on quality characteristics (∆T), variance analysis (ANOVA) was applied to test results at 95% confidence level. According to statistical results, it was determined that the response rates of ΔT values from the control factors were determined as inlet pressure, the number of orifices and nozzle material, respectively. Validity of the optimization was checked with confirmation tests, and the optimization proved to be used in evaluation of RHVT performances.

Dust devil winds: Assessing dry convective vortex intensity limits at planetary surfaces

An estimate of the maximum winds associated with dry convective vortices is determined simply as Vmax = ΔT(2Cp/Ta)0.5, where ΔT is equal to half of the maximum surface-atmosphere temperature contrast, Cp is the specific heat capacity, and Ta the background temperature of the atmosphere. The ΔT estimate, and the resultant winds, have strong support from a wide range of observations on Earth and Mars. The model results in maximum predicted vortex winds of 29, 53, 2.7 and 2.0 m/s for Earth, Mars, Titan and Venus respectively, the ΔT values for the latter two bodies being determined from surface energy balance models. The maximum vortex winds in well-documented observations on Earth and Mars appear to be ~25 m/s and ~ 30 m/s respectively, consistent with the model limits.

In vivo temperature rise and acute inflammatory response in anesthetized human pulp tissue of premolars having Class V preparations after exposure to Polywave® LED light curing units

ObjectiveTo evaluate the influence of light emitted from two Polywave®, LED light-curing units (LCU) on in vivo pulp temperature (PT) rise and signs of acute inflammatory response in pulps of human premolar having deep Class V preparations. MethodsSixty intact, first premolars from 15 volunteers requiring extraction received infiltrative anesthesia. A sterile thermocouple probe was inserted within the pulp tissue through a minute occlusal pulp exposure in only 45 teeth (n = 9) to continuously monitor PT (°C). A deep buccal Class V preparation was created, and the surface was exposed to light from a commercial Polywave LCU (Bluephase 20i (20i), Ivoclar Vivadent) or from an experimental LCU (Exp) using the exposure modes (EM): 1s/Exp and 2s/Exp, 10s/20i, 20s/20i, and 60s/20i. Peak PT and PT rise values above baseline (ΔT) data were evaluated using a one-way ANOVA followed by Tukey’s post-hoc test (α = 5%). Teeth used for histological and immunohistochemical analyses (n = 3) were extracted approximately 2 h after exposure to the LCU. ResultsNo significant difference in peak PT and ΔT values was noted between 2s/Exp and 20s/20i groups, which both exhibited higher values than 1s/Exp and 10s/20i groups (p < 0.001). Dilated and congested blood vessels were seen after exposure to 1s/Exp, 2s/Exp, or 60s/20i EMs. The expression of IL-1β and TNF-α tended to be more intense when higher irradiance was delivered. SignificanceAlthough higher irradiance delivered over a short exposure caused lower PT rise than 5.5 °C, such EMs should be used with caution, as they have more potential to harm the pulp tissue.

Evaluation of thermally activated furniture on thermal comfort and energy consumption: An experimental study

Personalized Comfort Systems (PCS) have been seen as an effective alternative to provide thermal comfort along with reducing energy consumption. This paper contains the methodology and results of a study conducted in a laboratory environment that aims to evaluate Thermally Activated Furniture (TAF) panels. These panels mounted in front and on the side of a workstation as space partition panels, can provide thermal comfort and have the potential to save energy. The experiments were carried out in a controlled thermal comfort chamber using a thermal mannequin having 22 body segments and TAF. A total of 15 cases were examined against a reference case with an aim to understand the impact of TAF on the change in PMV, Skin Temperature (Tskin) and Heat Flux (Φ) of 22 individual body segments and change in the energy consumption. The combinations of three Room Air Temperatures (Tair) i.e. 26 °C, 28 °C and 30 °C were tested with a combination of four surface temperature (Tsur) ranging from the difference between Tair and Tsur 2 to 8 °C. For the entire study, Relative Humidity (RH) was maintained at 50%. The results indicate a change in PMV by about 0.15 votes towards the cooler side when the difference between Tair and Tsur was Δ2°C for the three Tair cases. The PMV changed by about 0.5 votes in the case of the Δ8°C difference between Tair and Tsur. The increase in ΔT values was found to increase the cooling thermal energy consumption relative to the baseline case without having PCS in operation, whereas the increase in Tair caused a decrease in the cooling thermal energy consumption.

Nitrogen Oxide Emissions from Premixed Reacting Jets in a Vitiated Crossflow

ABSTRACT This paper describes nitrogen oxide (NOx) measurements from a reacting jet in crossflow (RJICF). The NOx production of the RJICF is controlled by jet stoichiometry, crossflow temperature and composition, and the mixing rates between the fluid streams. Mixing occurs both pre- and post-flame. Pre-flame mixing refers to mixing between the reactant jet and the crossflow prior to combustion and determines the stoichiometry of burning; it is controlled by degree of flame lifting, LO, and the shear layer vortices. Post-flame mixing refers to mixing of these secondary combustion products with the crossflow; it is controlled by the counter-rotating vortex pair. The literature has clearly shown a monotonic increase in RJICF NOx production with its bulk average temperature rise (ΔT) but also indicated significant dependencies on momentum flux ratio (J), jet stoichiometry (ϕjet ), and other parameters. Moreover, these parameters are always coupled for a given geometry (e.g., LO varies with ϕjet ), and the fundamental influence parameters require clarification. To address this, significant effort was spent in this work on differentiating these coupled effects. NOx measurements were obtained from premixed ethane/methane/air jets injected into a vitiated crossflow of lean combustion products, for ΔT values between 75 and 350 K. Data were obtained at two crossflow temperatures (1350 K and 1410 K), two jet geometries, J values from 6 to 40, and ϕjet from 0.8 to 8.0. Ethane/methane ratio was varied to influence flame lifting independent of other parameters. Jet geometry was varied to influence shear layer vortex growth rates and, hence, pre-flame mixing rates. Overall, these data are consistent with the idea that NOx emissions are largely controlled by the stoichiometry at which combustion actually occurs, referred to as ϕFlame. ϕFlame is influenced by ϕjet and pre-flame mixing of the jet and crossflow that, in turn, depend upon LO, nozzle geometry, and crossflow temperature. While this result is expected, it manifests itself in complex manners. For example, NOx levels were observed to be nearly independent of ϕjet for a range of conditions, due to the coupled dependence of ϕjet and LO. Similarly, NOx emissions are a factor of three lower in the nozzle jet geometry relative to a fully developed exit flow, due to enhanced pre-flame mixing. From a practical point of view, the key implication of these results is its suggestion for minimizing NOx production at a given ΔT – designing injection schemes that enhance flame lifting and shear layer vortex growth rates. Finally, there are indications in the data of additional post-flame mixing effects that require further work to clarify.

Nighttime Cool Skin Effect Observed from Infrared SST Autonomous Radiometer (ISAR) and Depth Temperatures

AbstractThe nighttime ocean cool skin signal ΔT [defined as skin sea surface temperature (SSTskin) minus depth SST (SSTdepth)] is investigated using 103 days of matchups between shipborne Infrared SST Autonomous Radiometer (ISAR) SSTskin and water intake SSTdepth at ~7.1–9.9-m depths, in oceans around Australia. Before data analysis, strict quality control of ISAR SSTskin data is conducted and possible diurnal warming contamination is carefully minimized. The statistical distribution of ΔT, and its dependencies on wind speed, heat flux, etc., are consistent with previous findings. The overall average ΔT value is −0.23 K. It is observed that the magnitude of the cool skin signal increases after midnight and a coolest skin offset (with an average value of −0.36 K) is found at around dawn. The dependency of ΔT on SST conditions is observed. Direct warm skin events are discovered when the net heat flux direction is from the atmosphere to the ocean, which is more likely to occur at high latitudes when the air is very humid and warmer than the SST. In addition, several cool skin models are validated: one widely used physical model performs best and can capture most skin-effect trends and details; the empirical models only reflect the basic features of the observed ΔT values. If the user cannot apply the physical model (due to, e.g., the algorithm complexity or missing inputs), then the empirical parameterization in the form proposed in a 2002 study can be used. However, we recommend using a new set of parameters, calculated in this study, based on much more representative dataset, and with more rigorous quality control.

Cluster expansion Monte Carlo study of indium-aluminum segregation and homogenization in CuInSe2-CuAlSe2 pseudobinary alloys.

The influence of temperature and Al content on the segregation and homogenization behaviour of In-Al atoms in CuIn1-xAlxSe2 (CIAS) pseudobinary alloys is studied using a combination of cluster expansion Monte Carlo simulations and first-principles calculations. Such alloys are promising materials for a number of solar-energy-related applications. We found that the segregation of In-Al atoms in CIAS alloys with different Al contents occurs at relatively low temperatures. The cluster morphology of Al(In) atoms in CIAS alloys at 73 K appears in an ellipsoidal, rod-like or lamellar form, depending on the Al(In) content. The spatial distribution of In-Al atoms becomes homogeneous as the temperature increases. By determining the inhomogeneity degree σ of In-Al distributions in CIAS alloys at a series of temperatures, we found that the variation of σ with temperature (T) for all the considered CIAS alloys are sigmoidal in general and the sharp decrease in σ within a certain temperature range implies the occurrence of inhomogeneous-to-homogeneous phase transition. The inhomogeneity degree σ of CIAS alloys before or after the phase transition (phase segregation) increases as the content of Al(x) and In(1 - x) atoms gets closer. The σ(T) data points obtained by us can be well fitted with the Boltzmann function, which can give several physically meaningful parameters such as the phase transition temperature T0, temperature range of phase transition ΔT and so on. The fitted T0 and ΔT values for CIAS alloys with different Al content were proved to be reliable. The novel method for predicting the T0 and ΔT may be applied to many other binary or pseudobinary material systems with positive formation energy.

Genomic regions and pathways associated with thermotolerance in layer-type strain Taiwan indigenous chickens.

This study aimed to investigate genetic markers and candidate genes associated with thermotolerance in a layer-type strain Taiwan indigenous chickens exposed to acute heat stress. One hundred and ninety-two 30-week-old roosters were subjected to acute heat stress. Changes in body temperature (BT, ΔT) were calculated by measuring the difference between the initial BT and the highest BT during heat stress and the results were categorized into dead, susceptible, tolerant, and intermediate groups depending on their survival and ΔT values at the end of the experiment. A genome-wide association study on survival and ΔT values was conducted using the Cochran-Armitage trend test and Fisher's exact test. Association analyses identified 80 significant SNPs being annotated to 23 candidate genes, 440 SNPs to 71 candidate genes, 64 SNPs to 25 candidate genes, and 378 SNPs to 78 candidate genes in the dead versus survivor, tolerant versus susceptible, intermediate versus tolerant, and intermediate versus susceptible groups, respectively. The annotated genes were associated with apoptosis, cellular stress responses, DNA repair, and metabolic oxidative stress. In conclusion, the identified SNPs of candidate genes provide insights into the potential mechanisms underlying physiological responses to acute heat stress in chickens.

Effect of Gd2O3 on luminescence properties of RE ions in germanium-tellurite glasses

The system of Ho3+/Yb3+ co-doped Ge-Te-Ga-Gd glasses has been successfully prepared by traditional melting method. The thermal stability, Raman spectroscopy and mid-infrared luminescence were studied and analyzed systematically. The effectively enhanced thermal stability of the sample was obtained with the increasing introduced Gd2O3, which was confirmed by the positive ΔT values. The improved robustness and structural stability of the glass network were analyzed through Raman spectroscopy. Enhanced 2–3 μm emissions have been obtained by certain content Gd2O3 with an optimal choice of 15 mol% additive amount under 980 nm pumping. Furthermore, luminous parameters including J-O values, absorption, emission and gain cross sections have been presented together with energy transfer mechanism. Hence, this paper presents a new choice of Ho3+/Yb3+ co-doped Ge-Te-Ga-Gd glass as potential mid-infrared laser materials.

Validity of thermography for measuring burn wound healing potential.

Accurate assessment of burn wound depth and the associated healing potential is vital in determining the need for surgical treatment in burns. Infrared thermography measures the temperature of the burn wound noninvasively, thereby providing indirect information on its blood flow. Previous research demonstrated that a small, low‐priced, handheld thermal imager has an excellent reliability, but a moderate validity for measuring burn wound healing potential. A new and more sensitive version of this convenient device has become available. The aim of this study was to evaluate the validity of thermography for measuring burn wound healing potential, compared to Laser Doppler Imaging (LDI) as a reference standard. Thermal images and LDI scans were obtained from burn wounds between 2 and 5 days postburn. Temperature differences between burned and nonburned skin (ΔT) were calculated. To evaluate validity, ΔT values were compared to the healing potential categories assessed by LDI. Two receiver operating characteristic curves were created and two ΔT cutoff values were calculated to illustrate the ability to discriminate between burn wounds that heal in a time period of less than 14 days, between 14 and 21 days, and more than 21 days. Between June and October 2018, 43 burn wounds in 32 patients were measured. ΔT cutoff values of 0.6°C (sensitivity 68%, specificity 95%) and −2.3°C (sensitivity 30%, specificity 95%) were calculated to discriminate between burn wounds that heal in <14 and ≥14 days, and burn wound that heal in ≤21 and >21 days, respectively. This study shows a good validity of the feasible thermal imager for the assessment of burn wound healing potential. Therefore, we consider it a promising technique to be used for triage in local hospitals and general practices, and as a valuable addition to clinical evaluation in burn centers.

Clinical utility of transanal indocyanine green near-infrared fluorescence imaging for evaluation of colorectal anastomotic perfusion.

Although indocyanine green (ICG) fluorescence imaging has been reported to be useful for assessing colorectal perfusion, unstable quantification remains an issue. We performed ICG fluorescence observation from the luminal side and examined the usefulness of the transanal approach. A total of 69 patients who underwent left-side colon surgery were enrolled in this cohort study. After the anastomosis had been constructed, ICG 0.2mg/kg was injected intravenously. The anastomotic site was then observed by a scope inserted transanally. The following items were examined in the areas of the anastomotic site with the highest- and lowest-fluorescence intensity: maximum fluorescence (Fmax), time from ICG injection to Fmax (Tmax), time from start of dyeing to Fmax (ΔT), and the contrast pattern of the mucosa. Anastomotic leakage (AL) occurred in nine cases. Tmax and ΔT values of the lowest-fluorescence area in the distal intestine showed significant differences in the cases with AL (P = 0.015 and P = 0.040, respectively). Regarding the contrast pattern of the mucosa of the lowest-fluorescence area in the proximal and distal intestine, the patients in whom the vessels were not depicted in the area had a significantly higher incidence of AL than those in whom vessels were depicted in the area (P = 0.031 and P = 0.030, respectively). Some of the areas in which vessels were not depicted by ICG fluorescence observation from the luminal side corresponded to the points of leakage. There were heterogeneous changes that might not be grasped by observation from the serosal side. Transanal ICG fluorescence imaging can evaluate perfusion over the entire circumference of the anastomosis in detail and aid in assessing the risk of AL. Therefore, the examination of the detailed low-perfusion area enables us to take measures for AL and to search for safer operative managements.

Novel Experimental Approach to Determine Elastocaloric Latent Heat

One of the most important parameters of superelastic shape memory alloys to be used in elastocaloric cooling and heating processes is their specific latent heat. Usually, the latent heat of a material is determined by differential scanning calorimetry (DSC) where the material phase transformation is induced thermally under zero stress. During elastocaloric processes however, the latent heat becomes accessible by stress-induced transformation under tensile or compression loading and unloading of the sample. In recent elastocaloric experiments, we observed drastic differences between latent heat values determined in DSC experiments and the ΔT values observed in nearly adiabatic elastocaloric cycles, which reflect the latent heat; in fact, the DSC experiments predicted rather pessimistic values and thus poor cooling performance. Based on these observations we developed and tested a novel experimental approach to determine the latent heat of superelastic materials directly during the elastocaloric process. By comparing or combining direct Joule heating with the strain based process we are able to accurately determine the latent heat for both tensile loading and unloading for any elastocaloric heating or cooling process. Furthermore, the influence of applied mechanical parameters as well as material conditioning on the latent heat can be observed in the elastocaloric experiment.

Seasonal and Diurnal Surface Temperatures of Urban Landscape Elements

In the context of the Urban Heat Island effect, landscape professionals need practical guidance to design for managing surface urban heat. The apparent surface temperatures of samples of 19 hard and soft landscape elements (LEs) found in Perth (Australia) were measured. Thermal images of LE samples on an oval were taken at a 1 m height. The study was conducted in two phases. Phase 1 LE surface temperatures relative to ambient (ΔT) were measured over one day in all four seasons. LEs were ranked by average ΔT, and maintained a similar order across seasons, with summer LEs the hottest. Some LEs were 30–44 °C above ambient in spring and autumn, so these seasons are also significant. Phase 2 repeated the summer test, but used only 14 larger LEs, which were well-coupled to the ground, i.e. more representative of in situ LEs. ΔT values were averaged over daytime and evening periods. Larger LEs were generally hotter than corresponding smaller LEs, with the effect more evident for heavier, denser LEs in the evenings. Future tests should be performed as per phase 2. Averaged measured values of grey pavers were the hottest, whilst ground-cover plants were the coolest. In the evening, grey pavers were also the hottest, whilst decking, soil and turf grass were the coolest. This data will help landscape professionals to assess and compare the thermal performance of different landscape designs, particularly when considering the time of use.

Electrocaloric properties of Ba0.8Sr0.2Ti1-xZrxO3 (0≤x≤0.1) system: The balance between the nature of the phase transition and phase coexistence

We investigate the electrocaloric effect of Ba0.8Sr0.2Ti1-xZrxO3 (0 ≤ x ≤ 0.1) system by comparing the electrocaloric temperature change (ΔT) of different compositions belonging to the different regions of the phase diagram. We show that as the amount of Zr increases, electrocaloric temperature change initially decreases as the phase transition gets diffuse then increases again as the composition of the samples are located closer to the critical point where different ferroelectric phases coexist. Since the critical point is reached at relatively low Zr substitution levels (i.e. around x = 0.07), the phase transition doesn't get too diffuse and thefore the compositions between x = 0 and x = 0.10 (which contains higher Zr than the critical point composition) have comparable ΔT values. Electrocaloric efficiency of these compositions (x = 0.03, 0.05 and 0.07) is around 0.20 K mm/kV at 20 kV/cm. We discuss the results in terms of the balance between the nature of the phase transition and proximity to the critical point, based on the phase diagram.