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The novel potential of hybrid phase change materials (PCM) as a mix of animal fat, specifically pork fat (lard), with edible and waste oil from the food processing industry was investigated in this paper. Lard is a relatively accessible phase change material of organic origin, with a significantly lower unit price when compared to conventional PCM materials (wholesale price of lard can be less than 0.50 €/kg). On an annual basis, a large amount of lard is thrown away because it has become inedible from a nutritional point of view. Experimental results directed that the addition of oils can improve the thermal constants of lard such as thermal conductivity, volumetric heat capacity, with the thermal diffusivity being reduced. The best result was achieved for a hybrid PCM as a combination of pork fat and waste burnt oil as the thermal conductivity was improved by 1.4% and the volumetric heat capacity by 11% with respect to the base PCM, i.e., pork fat (lard). The novel proposed hybrid PCMs are more economically viable, enabling the utilization of waste resources, and securing less environmental impact when compared to conventional PCMs as organic materials. The possible application of lard should be further investigated for specific engineering applications, such as thermal energy storage. [ABSTRACT FROM AUTHOR]

Abstract This article characterizes a cellular system prepared from alkali activated Class C fly ash mixed with a preformed foam. The resulting mixture was cast at three densities between 1000 and 1400 kg/m3 and all tests were conducted under ambient drying conditions resulting in densities between 940 and 1310 kg/m3. A phase analysis of the components in the cell wall was performed using X-ray diffraction. The compressive strength ranged from 3 to 9 MPa, while the corresponding modulus of elasticity was between 850 and 1700 MPa. The thermal constants were measured using the Transient Plane Heat Source (TPS) technique per ISO 22007-2. Sound absorption and noise reduction coefficients were evaluated using the impedance tube method per ASTM C384-04. The results show that at an oven dry density near 1000 kg/m3, this alkali activated system is a viable alternative for thermal and sound insulation with properties comparable to those of current commercially available options. [ABSTRACT FROM AUTHOR]

Using equations based on the law of total effective temperatures, we estimated the thermal constants (LDT, the lower development threshold, and SET, the sum of effective temperatures) of egg development for 14 populations of 13 species of carabid beetles (eight belonging to the tribe Zabrini, one to Platynini and four to Pterostichini). We compared the estimates of the thermal constants obtained using three commonly used equations (D = SET / (T - LDT); 1 / D = a + b . T, where LDT = -a / b, and SET = 1 / b; and D . T = SET + D . LDT) and two data formats: data points for all the individuals and means for each temperature. We found that, for most species, estimates of both LDT and SET of egg development obtained using the three models were similar and that using means resulted in larger standard errors (SE) than using all data points. We provide evidence for inter-correlation among the thermal constants, showing that a decrease in the estimate of one constant is accompanied by an increase in the estimate of the other constant. For seven species for which sufficient data were available we investigated the geographical variation in their thermal constants. We found significant variation in both constants for three species, in only one in one species and in three species there was no significant variation among geographically distant populations at p < 0.05. For eight out of the nine autumn-breeding species studied, egg mortality significantly increased at high temperatures. For future studies, we recommend the use of the third method (D . T = SET + D . LDT) for estimating thermal constants for several reasons: (i) it is linear (i.e., simple to compute); (ii) the thermal constants are parameters of the equation, and therefore, their SEs are directly estimated; (iii) it allows the use of all data points (i.e., reduces the SE of the estimates of thermal constants); and (iv) the thermal requirements of different species or populations can be directly compared using ANCOVA.

Effects of temperature (16, 20, 24, 28 and 32 ± 1 °C), host plant (Nicotiana tabacum L.) and factitious prey (eggs of Ephestia kuehniella Zeller) on immature development of three recently found Neotropical mirids, Campyloneuropsis infumatus (Carvalho), Engytatus varians (Distant) and Macrolophus basicornis (Stal) were studied at RH 70 ± 10% and 12h photophase in climate cabinets. These mirids are being evaluated for biological control of the South American tomato borer Tuta absoluta (Meyrick) and other pests on tomato. Survival of eggs of the three mirid species on tobacco was high (> 80%) at 16-28 °C, but lower (< 80%) at 32 °C. Development times decreased with increasing temperature from 16-28 °C. Nymphal survival was higher (84-96%) at 20, 24 and 28 °C than at 16 and 32 °C (46-83%). The sex ratio of C. infumatus was strongly female biased at all temperatures, whereas it was 1:1 for the other two species. The lower temperature thresholds for egg-adult development of C. infumatus, E. varians and M. basicornis were 9.4, 9.4 and 7.9 °C, and their thermal constants were 384.6, 384.6 and 476.2 DD, respectively. Temperatures between 24 to 28 °C are best for immature performance and for rearing of these mirids species. Eggs of the factitious host E. kuehniella provide adequate food for their mass production. Optimal temperatures for best mirid predator performance are similar to those for the pest T. absoluta, indicating good climate matching. [ABSTRACT FROM AUTHOR]

Temperature-dependent development, longevity and parasitism of the parasitoid Aphidius ervi Haliday was measured at four constant temperatures between 15°C and 30°C using Aphis pomi de Geer as host. The thresholds for egg-mummy and mummy-adult development were 6.8°C and 3.9°C, respectively. Development into mummies required an average of 146.3 degree-days (DD), while development into adults took an average of 85.3 DD. Longevity was increasing linearly in the range from 15°C to 25°C (8-15 days), but was lower at 30°C (11 days). The relationship between parasitism, recorded as percent aphids mummified, and temperature was increasing at the temperatures 15-25°C, but decreasing at higher temperatures; 10.8% of the aphids were parasitised at 15°C, 15.9% at 25°C and 14.6% at 30°C. These results are compared with previously reported data on temperature-dependent development of A. ervi on a different host.

The development of individual cotton bollworm stages depending on the ambient temperature was studied in laboratory conditions. The effect of temperature on the development of all stages of Helicoverpa armigera was studied at three constant temperatures of 20, 25, and 30°C in temperature-controlled chambers. The temperature dependence of the developmental rates and the thermal thresholds were established by means of linear regression. Our data has established following optimal temperatures: the lower thermal threshold for the development of the Helicoverpa armigera eggs is 14.83°C, for the development of the larvae is 11.34°C and for the development of the pupae is 8.18°C. The termal constant for the development of the Helicoverpa armigera eggs is 64.10 day-degrees, for the development of the larvae is 344.83 day-degrees and for the development of the pupae is 222.22 day-degrees. The lower thermal threshold for the total Helicoverpa armigera development is 11.50�C and the thermal constant is 625.00 day-degrees.

The effect of temperature on the development of the 1st instar of Periplaneta australasiae (Fabr.) was studied at the four constant temperatures of 21°C, 24°C, 27°C and 30°C in temperature-controlled chambers. Mortality was 50% at 30°C, and 10% at 21°C, 24° and 27°C. Thermal constants were established by plotting linear regression to development rate. The thermal threshold for the development was 17.1°C and the thermal constant for 1st instar larvae was 147.1 day-degrees. As "safe temperature" (ts) - the temperature to be maintained in stores or food premises to prevent the development of a pest species - we recommend 16°C.

Development rates of the eggs of 9 species, larvae of 6 species and pupae of 6 species of the genus Amara (Coleoptera: Carabidae) were recorded at five constant temperatures between 17 and 28°C, and thermal constants for each development stage calculated. The lower development threshold varied between 9.2-13.5°C for different stages and species. Rate isomorphy, which implies the existence of a common temperature threshold for all development stages, was demonstrated in 5 species. The sum of effective temperatures differed between stages. On average the egg stage took 18%, the first larval instar 13%, second instar 13%, third instar 35% and pupa 21% of the total development time. A poor diet increased the SET of the larvae. The results are compared with published data on Carabidae.

Colonies of M. rubra, M. ruginodis and M. scabrinodis were collected in four geographic regions: Kiev, Ukraine (50.5°N, 30.5°E - first two species), Vladimir, Russia (56.2°N, 40.4°E - only last species), St. Petersburg, Russia (59.3°N, 30.3°E - all three species) and Chupa, Murmansk prov., Russia (66.3°N, 33.7°E - last two species). After artificial overwintering experimental cultures consisting of 150 workers and one queen were established and kept at 16, 18, 20, 22, 24 and 26°C under long (22 h) day lengths. The workers reared eggs laid by queens into rapid (non-diapause) brood pupae and diapause larvae, which were removed and counted. The results showed the distinct latitudinal variation in the temperature effects on rapid brood rearing and in the thermal requirements for development. First, the period during which new rapid brood pupae appeared was found to be longer and the total number of pupae produced to be greater in ants from more southern populations. The number of diapause larvae reared by ant cultures was also usually greater, in ants from southern sites. Second, low temperatures reduced the period of rapid brood production and the number of pupae reared to a greater degree in ants from northern populations. It means that northern Myrmica colonies rear rapid brood under lower temperatures evidently worse in comparison with ants from southern regions. Third, eggs and larvae from more northern sites appeared to develop faster than southern brood at temperatures above 16-18°C. This was because brood development in northern populations was more temperature dependent, i.e. characterised by higher slopes of regression lines of development rate on temperature. The sum of effective temperatures decreased with the advance to North. The higher slopes were always associated with higher thermal thresholds for development. We conclude that the reaction norm of Myrmica colonies, in response to temperature, changes according to the local climate in such a way that brood rearing, growth and development of individuals become more temperature dependent in more severe environments with colder and shorter summers. This lead to the increase of the physiological and developmental responses at higher temperatures at the expense of a decrease within lower temperature range. In fact Myrmica colonies from northern populations need on average higher temperatures in their nests for successful production of new adults as compared to southern ants.

The development stages of a species may have an identical lower development threshold (LDT) and proportionally different durations. This phenomenon called "rate isomorphy" (RI) has been demonstrated for a number of insect species. In contrast, the growing day degrees accumulated over the period of larval development (sum of effective temperatures SET) should be plastic and vary with environment conditions. The prediction from RI is that, with changing conditions, the uniform LDT should be accompanied by differences in development time which remain proportional at different temperatures. This was tested by investigating the effect of diet on thermal requirements for development of larvae of the polyphagous species Autographa gamma (L.) (Lepidoptera: Noctuidae). The larvae were kept at 15.0, 20.3 and 26.7°C and fed on leaves of 13dicotyledoneous herb and tree species. The proportion of total development time spent on a particular diet was plotted against temperature. The existence of RI was inferred from a zero change in development time proportion with changing temperature. This rigorous test supported RI for 3 of 9 diets where development was completed in all temperatures. The LDT observed on 11 diets where the larvae completed development in at least 2 temperatures varied between 9.3 and 11.0°C while SET varied between 167 and 353 day degrees (dd). Assuming RI, LDT and SET for those 9 diets were recalculated. The recalculated LDT was 10.0°C and SET varied between 177-257 dd. The SET increased with decreasing water content and decreasing nitrogen content of food. Worsening food quality decreased food consumption, metabolic and food conversion efficiency, and the relative growth rate of the larvae. Increasing metabolic costs of development were thus positively correlated with SET. The standardized rate of growth (mg.dd-1) was typical for particular diets. Pupal mass decreased with increasing temperature and, within each temperature, with development length.

III–V semiconductors are extensively used in infrared sensor applications due to their superior structural and optical properties. Due to the extremes in the manufacturing and operating temperatures of the sensors, the knowledge of temperature-dependent elastic constants of these materials is of great importance. However, reliable measurements across a large range of temperatures prove difficult due to limitations of experimental setups. Density functional theory calculations present an affordable alternative. In this work, temperature-dependent elastic properties of InSb and GaSb are investigated using density functional theory within the quasiharmonic approximation. Calculated properties relevant for operation in a wide temperature range are presented including second order elastic constants, Young's modulus (E), shear modulus (μ), Poisson's ratio ν and the coefficient of thermal expansion (α). Our results are compared to available experimental values and good agreement is observed. • Elastic constants of GaSb and InSb compounds are obtained from ab initio DFT simulations in between 1K and ∼ 1000K. • Thermal constants of GaSb and InSb compounds are obtained from ab initio DFT simulations in between 1K and ∼ 1000K. • A closed form analytical free energy function expression is proposed for cubic crystals and the temperature variation of elastic constants are derived for GaSb and InSb according to the results obtained from DFT simulations. [ABSTRACT FROM AUTHOR]

Using equations based on the law of total effective temperatures, we estimated the thermal constants (LDT, the lower development threshold, and SET, the sum of effective temperatures) of egg development for 14 populations of 13 species of carabid beetles (eight belonging to the tribe Zabrini, one to Platynini and four to Pterostichini). We compared the estimates of the thermal constants obtained using three commonly used equations (D = SET / (T - LDT); 1 / D = a + b . T, where LDT = -a / b, and SET = 1 / b; and D . T = SET + D . LDT) and two data formats: data points for all the individuals and means for each temperature. We found that, for most species, estimates of both LDT and SET of egg development obtained using the three models were similar and that using means resulted in larger standard errors (SE) than using all data points. We provide evidence for inter-correlation among the thermal constants, showing that a decrease in the estimate of one constant is accompanied by an increase in the estimate of the other constant. For seven species for which sufficient data were available we investigated the geographical variation in their thermal constants. We found significant variation in both constants for three species, in only one in one species and in three species there was no significant variation among geographically distant populations at p < 0.05. For eight out of the nine autumn-breeding species studied, egg mortality significantly increased at high temperatures. For future studies, we recommend the use of the third method (D . T = SET + D . LDT) for estimating thermal constants for several reasons: (i) it is linear (i.e., simple to compute); (ii) the thermal constants are parameters of the equation, and therefore, their SEs are directly estimated; (iii) it allows the use of all data points (i.e., reduces the SE of the estimates of thermal constants); and (iv) the thermal requirements of different species or populations can be directly compared using ANCOVA. [ABSTRACT FROM AUTHOR]

Impedance spectroscopy is a well-established technique for the study of semiconductors and energy-related devices. However, in the area of thermoelectrics (TEs), this technique is not frequently used and there is a lack of a physical background for a proper interpretation of the results. Usually, in the low frequency regime, the impedance spectrum of TE modules working in cooling mode is characterized by a semicircle which can be modelled as a parallel connection of a resistor and a capacitor. Here, we present a theoretical analysis to understand the origin of both parameters in bulk TE modules working as Peltier coolers. The analysis introduces a thermoelectric capacitance and a thermoelectric resistance that are defined by the temperature, the Seebeck coefficient and the thermal properties of the module (specific heat and thermal conductivity, respectively). The product of both provides a time constant that directly relates to the thermal diffusivity. Our analysis provides a theoretical model able to interpret the low frequency results and obtain relevant thermal parameters from a single impedance measurement. [ABSTRACT FROM AUTHOR]

In this paper we present a novel, time-delay approach using a copper-coated fiber. Piezo optical-fiber stretchers and temperature-controlled fiber spools are normally used for a conventional time-delay lines. A copper-coated fiber preserves the performance of a standard single-mode optical fiber, while at the same time acting as an electrical wire, which can be effectively heated by applying an electrical current. As a result of the significant temperature change, the signal (group) delay can be properly adjusted and controlled. Compared to piezo optical-fiber stretchers and temperature-controlled fiber spools, much shorter lengths of fiber are required and a faster response time can be achieved. This paper also proposes a simple, lumped thermal model and thus a copper-coated fiber can be included in the heat-transfer and response-time calculations of a realistic system that involves surrounding elements (e.g., heatsinks). [ABSTRACT FROM AUTHOR]

Highlights: [•] Tests showed that Agonopterix umbellana was safe to release in Australia. [•] Establishment confirmed at Tasmanian release sites. [•] The life cycle is univoltine with larvae passing through six instars. [•] Lower development thresholds and thermal constants for all development stages were determined. [ABSTRACT FROM AUTHOR]

Investigations into the thermal physiology of weed biological control agents may elucidate reasons for establishment failure following release. Such studies have shown that the success of water hyacinth biological control in South Africa remains variable in the high-lying interior Highveld region, because the control agents are restricted to establishment and development due to extreme winter conditions. To determine the importance of thermal physiology studies, both pre- and post-release, this study compared the known thermal requirements of Eccritotarsus catarinensis ( Carvalho) ( Hemiptera: Miridae) released in 1996, with those of an agent released in 1990, Niphograpta albiguttalis ( Warren) ( Lepidoptera: Pyralidae) and a candidate agent, Megamelus scutellaris Berg ( Hemiptera: Delphacidae), which is currently under consideration for release. The lower developmental threshold (to) and rate of development (K) were determined for N. albiguttalis and M. scutellaris, using a reduced axis regression, and incorporated into a degree-day model which compared the number of generations that E. catarinensis, N. albiguttalis, and M. scutellaris are capable of producing annually at any given site in South Africa. The degree-day models predicted that N. albiguttalis (K = 439.43, to = 9.866) can complete 4-11 generations per year, whereas M. scutellaris (K =502.96, to = 11.458) can only complete 0-10 generations per year, compared with E. catarinensis (K = 342, to = 10.3) which is predicted to complete 3-14 generations per year. This suggests that the candidate agent, M. scutellaris, will not fare better in establishment than the other two agents that have been released in the Highveld, and that it may not be worth releasing an agent with higher thermal requirements than the agents that already occur in these high-lying areas. Thermal physiology studies conducted prior to release are important tools in biological control programmes, particularly those in resource-limited countries, to prevent wasting efforts in getting an agent established. [ABSTRACT FROM AUTHOR]

The use of phase-change materials (PCMs) in asphalt mixture is expected to solve some problems related to asphalt-pavement temperature, such as rutting behaviors and urban heat island effect. This study mainly evaluated the thermal and mechanical properties of asphalt mixtures with and without various PCMs (PCM-L, PCM-Z) using laboratory performance tests. The experimental tests included thermal conductivity and diffusivity, volumetric heat capacity, indoor temperature changes versus time when heated or cooled, indirect tensile strength, high-temperature rutting, and low-temperature cracking. In addition, a hot disk thermal constants analyzer was used to measure the thermal constants of asphalt mixtures. The results showed that different PCMs had different effects on the thermal constants of asphalt mixtures. Compared with control sample, the sample with PCM-L showed a higher thermal conductivity, whereas the sample with PCM-Z had a lower thermal conductivity. Moreover, PCM-Z exhibited a more-significant phase-change adjusting-temperature effect on asphalt mixtures than PCM-L. However, the addition of PCM to asphalt mixtures resulted in a decreased indirect tensile strength and a weakened rutting resistance, but the effect of PCM-Z was smaller than that of PCM-L. In addition, the asphalt mixture with PCM-Z exhibited better cracking resistance than the mixture with PCM-L and control mixture. Therefore, it is recommended to use PCM-Z in asphalt mixtures to solve the problem of pavement at high temperatures. [ABSTRACT FROM AUTHOR]

Abstract: The effect of temperature on life cycle of the solenopsis mealybug, Phenacoccus solenopsis Tinsley, on cotton (Gossypium hirsutum L.) was assessed under laboratory conditions at ten constant temperatures (18–40 °C). The development duration of female and male nymphal instars linearly decreased with the increase in temperature from 18 to 32 °C. Cumulative developmental time of females ranged from 43.9 d (18 °C) to 15.0 d (32 °C). Survival of crawlers to adulthood was lowest (<53%) at 20 and 36 °C and highest (80%) at 32 °C. The solenopsis mealybug exhibited obligate sexual ovoviviparous reproduction and the pre-oviposition period in mated females showed a significant decreasing trend between 20 °C (23.0 d) and 30 °C (9.5 d). The oviposition period of 10.2–11.5 d at ≥25 °C was nearly half the duration than at 20 °C and the highest fecundity (245 eggs + crawlers) was observed at 30 °C. Longevity of mated females was significantly prolonged at 20 °C (46.0 d) compared to 30 °C (21.4 d). Proportion of females was highest (97.5%) at 25 °C. Males required higher degree-days (363.6) for their cumulative development compared to females (317.5). Lower temperature thresholds estimated from the linear model for cumulative female and male development were 11.7 and 10.1 °C, respectively. The estimated optimum temperature thresholds for nymphal instars (32–33.4 °C) from β type distribution function were closer to the observed maximum developmental rate compared to Lactin-2 model. The population trend index using survival, fecundity, and sex ratio of P. solenopsis with an initial population of 100 crawlers in the Morris-Watt life table model indicated a potential population increase of 170.3 and 97.6 times at 30 and 35 °C, respectively, in the next generation. The usefulness of the information on the temperature-dependent life cycle of P. solenopsis in understanding its field abundance and distribution on cotton and implications for management is discussed. [Copyright &y& Elsevier]

Development of Dinoderus minutus was studied under laboratory conditions at five constant temperatures (15, 18, 25, 28, and 30°C) to estimate developmental thresholds and thermal requirements of the egg, larva, pupa, and egg-to-adult stages. Adults began to burrow along the grain into bamboo pieces within 24 h after cutting and continued across the grain. Female beetle oviposited an average of 9.1 eggs in the ensuing 24 h, all in the metaxylem. The average period for development of eggs, larva, and pupa were 5.4,43.8, and 4.6 d at 30°C, respectively. The development rate data were regressed through the x-axis to derive the thermal constants of 4.3, 6.8, and 4.5°C and thermal requirements of 113.6,909.1, and 96.2 DD to predict D. minutus egg oviposition to hatch, larva-to-pupa development, and adult emergence from pupa, respectively. The thermal threshold for egg-to-adult development was 6.4°C, with total thermal requirements of 1,111.1 DD. Oviposition, emergence, and thermal requirements for development of the various stages of D. minutus may be used for postharvest pest management of bamboo. [ABSTRACT FROM AUTHOR]

Effect of temperature on the life history of the mealybug Paracoccus marginatus Williams & Granara de Willink (Hemiptera: Pseudococcidae) was investigated in the laboratory. P. marginatus was able to develop and complete its life cycle at 18, 20, 25, and 30 ± 1°C. At 15, 34, and 35°C, the eggs hatched after 27.5, 5.9, and 5.5 d of incubation, respectively, but further development of the first-instar nymphs was arrested. No eggs hatched at 37°C. The developmental time for egg to adult was the longest at 18°C for both males and females. Approximately 80-90% of the eggs survived between 20 and 30°C. The highest fecundity was at 25°C with each female producing an average of 300 eggs. Adult longevity, and preoviposition and oviposition periods increased with decreasing temperature up to 25°C. The proportion of females was ≈42% at 25°C and was between 70 and 80% at 18,20, and 30°C. Adult males and females required 303.0 and 294.1 degree-days (DD), respectively, to complete their development. The estimated minimum temperature thresholds for the adult males and females were 14.5 and 13.9°C, respectively. For adult males, the estimated optimum and maximum temperature thresholds were 28.7 and 31.9°C; and for adult females, they were 28.4 and 32.1°C, respectively. The ability of P. marginatus to develop, survive, and reproduce successfully between 18 and 30°C suggests that it has the capability to develop and establish in areas within this temperature range. [ABSTRACT FROM AUTHOR]

The development of Bracon vulgaris Ashmead (Hymenoptera: Braconidae), parasitoid of the cotton boll weevil Anthonomus grandis Boheman (Coleoptera: Curculionidae), was studied at constant temperatures of 18, 20, 23, 25, 28, 30, 33, 35 and 38°C, 70±10% r.h. and 14:10 L:D period. The period from egg to adult of B. vulgaris varied from 8.6 (35°C) to 32.9 days (18°C). The eggs of this parasitoid became desiccated and did not hatch at 38°C. The lower development threshold (LDT) and thermal constants for development varied with B. vulgaris instar, but they were similar for males and females. The duration of the 1st, 2nd, 3rd and 4th B. vulgaris instars required, respectively, 9.36 degree-days above one LDT=12.27°C, 13.48 degree-days above one LDT=6.83°C, 11.65 degree-days above one LDT=9.41°C, and 12.82 degree-days above one LDT=10.78°C. B. vulgaris has physiological adaptations to different threshold temperatures and it shows high potential to be used against A. grandis in cotton crops. [ABSTRACT FROM AUTHOR]

Newton's law of cooling was used to analyze the fall in rectal temperature post mortem in 55 cases during refrigeration in a mortuary. As with solids of low thermal conductivity, there was an initial curvilinearity to the semilog plot lasting 1 to 11 hours (related to pelvic circumference) while the proper internal temperature distribution was becoming established. Thereafter there was a linear trend representing a constant percent cooling rate r which lasted up to 24 hours for adults. This was followed by a less steep trend of cooling rate r, which was 37% less than r. This diminution in cooling rate occurred when the rectal temperature fell below 10°C and was ascribed to a reduction in the thermal diffusivity of fat. r had the highest correlation with pelvic circumference. For the nude body in still air r=15.6% to 18.4% ( T −T)/hour for children, 3.8% to 9.4% for adults. Wind increased r; the decrease due to clothing was questionable because of the paucity of cases. [ABSTRACT FROM AUTHOR]