Transducer interface for multichannel wired telemetry in high temperature environment

Prolonged exposure to high humidity and high temperature environment can aggravate influenza virus infection through intestinal flora and Nod/RIP2/NF-κB signaling pathway

At present, the follow-up platform in the guidance device is mostly the direct drive mode of the motor. in order to reduce the weight and save space The way of wire rope indirect transmission is proposed. In the high-temperature environment, the wire rope will be thermally expanded during the transmission process, resulting in reduced transmission accuracy or even failed due to slippage, and similar problems may occur in the low temperature environment. Since the pre-tensioning device is not easy to set up in a small space, in this paper, the deformation of steel wire rope and transmission wheel in high and low temperature environment is calculated. By calculating the elongation of the steel wire rope in the high and low temperature environment and the thermal expansion of the transmission wheel, the advantages and disadvantages of the automatic tensioning effect of the rope system in high and low temperature environment can be analyzed and compared, which lays a foundation for the improvement of the whole transmission system.

The optical fiber Fabry-Perot interferometer (FPI) has been widely investigated as a potential temperature sensor. To function as a temperature sensor, the cavity of the FPI is typically constructed from either silica fibers or polymers. The silica cavity FPIs can function at temperatures exceeding 1 000 °C. However, their temperature sensitivity is constrained by their relatively low thermal optical coefficients and thermal expansion of silica materials. Although the polymer cavity FPI exhibits high temperature sensitivity, its cavity is susceptible to deterioration in high-temperature environments. Here, to overcome this challenge and achieve high-sensitivity temperature sensing in a high-temperature environment, we propose a new type of temperature FPI sensor by inserting and sealing a section of Cr20Ni80 metal microwire inside a section of a silica hollow core fiber (HCF) spliced to a standard single-mode fiber (SMF). The FPIs exhibit a high degree of temperature sensitivity due to the high thermal expansion of the Cr20Ni80 metal microwire. Since the Cr20Ni80 metal has a high melting temperature of 1 400 °C, such FPIs can function in high-temperature environments. Moreover, the temperature sensitivity of this FPI can be modified without affecting its reflection spectrum by changing the length of the metallic microwire within the hollow core fiber. The experimental results indicate that the proposed FPIs exhibit temperature sensitivity of greater than −0.35 nm/°C within the temperature range of 50 °C to 440 °C. Our proposed metal microwire-based FPIs are economical, robust, simple to fabricate, and capable of functioning in high-temperature environments, rendering them appealing options for practical applications.

The gut microbiome is vital to the physiological and biochemical functions of the host, and changes in the composition of these microbial communities may affect growth and adaptability to the environment. Pomacea canaliculata is an invasive freshwater snail which has become a serious agricultural pest. Temperature adaptation is considered an important reason for the widespread distribution of this species. To date, the contribution of the gut microbes to host fitness of P. canaliculata during long-term temperature stress is not well understood. In this study, the morphological changes and intestinal microbiome of P. canaliculata under long-term stress at low temperature (15°C) and high temperature (35°C) were investigated with laboratory experiments. Compared with control group (25°C), the alpha diversity increased and pathogenic bacteria enriched changed under high and low temperature stress. The effect of high temperature stress on the intestinal microbiome of P. canaliculata was more significant than that of low temperature stress. A sustained high temperature environment led to an increase in the abundance of pathogenic bacteria, such as Aeromonas and Enterobacter, and a decrease in the abundance of immune-related bacteria such as Bacteroidetes, Firmicutes, and Lactococcus. These intestine microbiome changes can increase the risk of diseases like intestinal inflammation, and lead to more deaths at high temperature environments. In addition, with the extension of stress time from 14 to 28 days, the beneficial bacteria such as Bacteroidetes, Firmicutes, and Lactococcus were significantly enriched, while potential pathogenic bacteria such as Pseudomonas, Acinetobacter, Shivalella, and Flavobacterium decreased, suggesting that intestinal microbiota may play an important role in host response to heat stress. These results are consistent with previously reported results that the survival rate of both male and female P. canaliculata no longer significantly reduced after 21 days of high temperature stress, suggesting that the surviving P. canaliculata had gradually adapted to high temperature environments under long-term high temperature stress.

We report on the high-power high-temperature long-pulse performance of the 8XX-nm diode laser bars and arrays, which were recently developed at Lasertel Inc. for diode laser pumping within high-temperature (130 °C) environment without any cooling. Since certain energy in each pulse is required, the diode laser bars have to provide both high peak power and a nice pulse shape at 130 °C. Optimizing the epi-structure of the diode laser, the laser cavity and the distribution of waste heat, we demonstrate over 40-millisecond long-pulse operation of the 8XX-nm CS bars at 130 °C and 100 A. Pumping the bar with 5-Hz frequency 15-millisecond rectangular current pulses, we generate over 60 W peak power at 100 A and 130 °C. During the pulse duration, the pulse shape of the CS bars is well-maintained and the power almost linearly decays with a rate of 1.9% peak power per millisecond at 130 °C and 100 A. Regardless of the pulse shape, this laser bar can lase at very high temperature and output pulse can last for 8 ms/2ms at 170 °C/180 °C (both driven by 60 A current pulses with 5-Hz frequency, 10 millisecond pulse width), respectively. To the best of our knowledge, this is the highest operating temperature for a long-pulse 8XX-nm laser bar. Under the condition of 130 °C and 100 A, the laser bars do not show any degradation after 310,000 10-millisecond current pulse shots. The performance of stack arrays at 130 °C and 100 A are also presented. The development of reliable high-temperature diode laser bar paves the way for diode laser long-pulse pumping within a high-temperature environment without any cooling.

In various industrial applications, including aviation, electric vehicles, and drilling, the demand for semiconductor devices and associated circuits with high thermal stability is progressively increasing. Wide-bandgap semiconductor Gallium Nitride (GaN) devices exhibit the advantages of fast switching capability, low on-resistance, and the ability to operate at high temperatures. These advantages have made them potential candidates for integrated circuits in high-temperature environments in recent years. Lateral GaN devices promote monolithic integration, which consequently increases power density and reduces cost of cooling systems. Hence, it is worthwhile to investigate the performance of GaN devices in high-temperature environments. This review aims to present a thorough review of high-temperature characteristics of GaN devices and integrated circuits. The performance of GaN devices at high temperatures, such as threshold voltage，saturation current and on-resistance, has been reviewed in response to different structures. The underlying degradation mechanisms related to the intrinsic properties of structures and fabrication technology are discussed at high temperatures. The thermal performance of GaN small signal integrated circuits and power converters was presented. This paper systematically examines the advantages and challenges of GaN devices and integrated circuits at high temperature environments.

The structural stability and mechanical integrity of boron nitride nanotubes (BNNTs) in high temperature environments are of importance in pursuit of their applications that are involved with extreme thermal processing and/or working conditions, but remain not well understood. In this paper, we perform an extensive study of the impacts of high temperature exposure on the structural and mechanical properties of BNNTs with a full structural size spectrum from nano- to micro- to macro-scale by using a variety of in situ and ex situ material characterization techniques. Atomic force microscopy (AFM) and high resolution transmission electron microscopy measurements reveal that the structures of individual BNNTs can survive at up to 850 °C in air and capture the signs of their structural degradation at 900 °C or above. In situ Raman spectroscopy measurements reveal that the BN bonds in BNNT micro-fibrils undergo substantial softening at elevated temperatures of up to 900 °C. The AFM-based nanomechanical compression measurements demonstrate that the mechanical integrity of individual BNNTs remain intact after being thermally baked at up to 850 °C in air. The studies reveal that BNNTs are structurally and mechanically stable materials in high temperature environments, which enables their usages in high temperature applications.

Influence of Calcium and Ascorbic Acid on Egg Quality

Birds that nest on the ground in hot environments employ behavioral and physiological mechanisms to prevent the overheating of their eggs and themselves (e.g. egg covering, belly soaking, orientation on the nest, ptiloerection, panting, and gular fluttering). One of the least energetically expensive behaviors employed during incubation at high temperatures is nest shading. During shading, the birds raise themselves onto their tibiotarsi so that the incubation patch is about 2 to 3 cm above the eggs. It has frequently been assumed that birds adopt shading behavior to allow for direct convective cooling of the eggs. However, an alternative hypothesis is that birds rise up onto their tibiotarsi in order to place themselves out of the boundary layer. In doing so, adult birds cool themselves directly by convection. The lowering of the adult's body temperature during nest shading may, of course, cool the eggs indirectly when the bird resumes incubation. We tested these hypotheses using a taxidermic model of a Crowned Plover (Vanellus coronatus), which nests in hot environments in South Africa. Field observations have shown that this species spends 20 to 50% of its time shading when incubating at high environmental temperatures. When we alternated the bird between incubating and shading positions, we found that bird temperature, but not egg temperature, was lowered by shading behavior. Furthermore, wind speed had a significant negative effect on bird temperature but not egg temperature. Therefore, our results support the hypothesis that shading behavior functions to lower the temperature of incubating adults rather than of the eggs.

Structural and functional materials that can operate in severe, high temperature environments are key to the operation of a wide range of energy generation systems. Because continued improvements in the energy efficiency of these systems is critical, the need for new materials with higher temperature capabilities is inevitable. Intermetallic compounds, with strong bonding and generally high melting points offer this possibility for a broad array of components such as coatings, electrode materials, actuators and/or structural elements. RuAl is a very unusual intermetallic compound among the large number of B2compounds that have been identified and investigated to date. This material has a very high melting temperature of 2050?C, low thermal expansion, high thermal conductivity and good corrosion resistance. Unlike most other high temperature B2 intermetallics, RuAl possesses good intrinsic deformability at low temperatures. In this program fundamental aspects of low and high temperature mechanical properties and deformation mechanisms in binary and higher order RuAl-based systems have been investigated. Alloying additions of interest included platinum, boron and niobium. Additionally, preliminary studies on high temperature oxidation behavior of these materials have been conducted.

<p indent="0mm">An organic light-emitting diode (OLED) based on rubrene doped with Ir(ppy)₃ was fabricated, and the magneto-electroluminescence (MEL) was used to analyze the optical-electric-magnetic properties and the exciton evolutions of the device under high temperature environment. The study finds that the light emission of the device comes from rubrene. Ir(ppy)₃ does not emit light, and its energy is completely transferred to Rubrene. The high temperature causes traps in the device, which hinders the diffusion and interaction of polaron pairs and excitons, causing the characteristic line of MEL to change from singlet exciton splitting to intersystem crossing. Through spin-orbit coupling and energy transfer, doping Ir(ppy)₃ can effectively enhance the optoelectronic performance and heat resistance of the OLED based on rubrene. This research not only deepens the understanding of the optical-electrical-magnetic properties and micro-mechanism of the OLED based on rubrene under high-temperature environments, but also provides a new method for enhancing the thermal stability of the device.

The purpose of the current research is to investigate the effects of body fluid replacement by carbohydrate-electrolyte drink on serum organ damage index and heat shock protein 70(HSP 70) during exercise in high ambient temperature. The subjects of the current research were 9 healthy male. The subjects were asked to perform treadmill running at 75%HRR for 60minutes in three different conditions controlled by the environmental chamber: 1) thermoneutral environment(ET), 2) high ambient temperature environment(EH), and 3) high ambient temperature environment and body fluid replacement by carbohydrate-electrolyte drink(EHS). Ambient temperature and relative humidity were set at 18℃ and 50%, respectively, for the theromoneutral environment, and 32℃ and 50% for the high ambient temperature environment. The identical amount of carbohydrate- electrolyte drink to the amount of body fluid loss for each subject was orally ingested in the EHS. Blood sampling were taken at pre-exercise, at immediately post-exercise, and at 60minute post-exercise for examining the levels of serum organ function enzyme and HSP 70. The serum concentration of creatine kinase(CK), lactate dehydrogenase(LDH), and HSP 70 immediately post exercise appeared to be significantly higher in EH compared to the ET(p.05). The serum concentration of aspartate aminotransferase(AST), alanine aminotransferase(ALT), blood urea nitrogen(BUN), creatinine, phosphorus was shown to significantly increase at immediately post exercise(p.05). On the base of the results of the current study, it is suggested that exercise in high ambient temperature can induce increase concentrations of organ function enzymes(CK, LDH) and HSP 70 which may negatively influence on human organ functions. Body fluid replacements during exercise in high ambient temperature, however, can attenuate the negative consequences of thermal stress on human organ functions by preventing dehydration and reducing thermal stress.

BackgroundShiga toxin (stx) genes have been transferred to numerous bacteria, one of which is E. coli O157:H7. It is a common belief that stx gene is transferred by bacteriophages, because stx genes are located on lambdoid prophages in the E. coli O157:H7 genome. Both E. coli O157:H7 and non-pathogenic E. coli are highly enriched in cattle feedlots. We hypothesized that strong UV radiation in combination with high temperature accelerates stx gene transfer into non-pathogenic E. coli in feedlots.Methodology/Principal FindingsE. coli O157:H7 EDL933 strain were subjected to different UV irradiation (0 or 0.5 kJ/m2) combination with different temperature (22, 28, 30, 32, and 37°C) treatments, and the activation of lambdoid prophages was analyzed by plaque forming unit while induction of Stx2 prophages was quantified by quantitative real-time PCR. Data showed that lambdoid prophages in E. coli O157:H7, including phages carrying stx2, were activated under UV radiation, a process enhanced by elevated temperature. Consistently, western blotting analysis indicated that the production of Shiga toxin 2 was also dramatically increased by UV irradiation and high temperature. In situ colony hybridization screening indicated that these activated Stx2 prophages were capable of converting laboratory strain of E. coli K12 into new Shiga toxigenic E. coli, which were further confirmed by PCR and ELISA analysis.Conclusions/SignificanceThese data implicate that high environmental temperature in combination with UV irradiation accelerates the spread of stx genes through enhancing Stx prophage induction and Stx phage mediated gene transfer. Cattle feedlot sludge are teemed with E. coli O157:H7 and non-pathogenic E. coli, and is frequently exposed to UV radiation via sunlight, which may contribute to the rapid spread of stx gene to non-pathogenic E. coli and diversity of shiga toxin producing E. coli.

In order to study the insulation performance of DC XLPE cables in fire environment, the conductivity of XLPE used in DC cable was tested at different temperatures, and the breakdown field strength of XLPE at different high temperatures was measured, which was carried out in a high-temperature oven. Meanwhile, the field strength distribution inside the DC cable under high temperature environment was simulated. The research results show that long-term overload of XLPE cable or high ambient temperature can cause the electric field strength of the cable insulation to increase, which will induce various defects and eventually cause insulation breakdown.

Enhancement of aluminum powder reaction behavior at high temperatures—Aluminum powders with “sea urchin structure” coated by AP