Extreme Environments Research Articles

A Strain‐Temperature Integrated Polymer‐Derived SiCN Ceramic High Temperature Sensor with Wide‐Range and Ultra‐Short Response Time

AbstractFabricating strain sensors with high response in a wide temperature and strain range is still a challenge, especially in high temperature harsh environments. Herein, a dual‐functional sensor with cantilever beam structure is fabricated using polymer‐derived SiCN ceramics, which can be applied for temperature and stain monitor. The performance of the integrated sensor is evaluated from room temperature to 1000 °C and the related sensing mechanism is analyzed. The prepared strain sensor has ultrafast response of 60 ms in the strain range of 0–3500 µε and the maximum strain rate can reach 46 200 µε s−1. Moreover, the sensor has excellent stability and ultra‐high sensitivity under high temperature environments. Additionally, the temperature can be detected separately up to 1000 °C without any disturbance. This attractive integration sensor with competitive sensitivity, excellent stability, ultrafast response speed, and broad range, has great potential to detect temperature and strain signals for practical application in high temperature extreme environments.

Newly identified nematodes from the Great Salt Lake are associated with microbialites and specially adapted tohypersaline conditions.

Extreme environments enable the study of simplified food-webs and serveas models for evolutionary bottlenecks and early Earth ecology. Weinvestigated the biodiversity of invertebrate meiofauna in the benthic zone of the Great Salt Lake (GSL), Utah, USA, one of the most hypersaline lake systems in the world. The hypersaline bays within the GSL are currently thought to support only two multicellular animals: brine fly larvae andbrine shrimp. Here, we report the presence, habitat, and microbial interactions of novel free-living nematodes. Nematode diversity drops dramatically along a salinity gradient from a freshwater river into the south arm of the lake. In Gilbert Bay, nematodes primarily inhabit reef-like organosedimentary structures built by bacteria called microbialites. These structures likely provide a protective barrier to UV and aridity, and bacterial associations within them may support life in hypersaline environments. Notably, sampling from Owens Lake, another terminal lake in the Great Basin that lacks microbialites, did not recover nematodes from similar salinities. Phylogenetic divergence suggests that GSL nematodes represent previously undescribed members of the family Monhysteridae-one of the dominant fauna of the abyssal zone and deep-sea hydrothermal vents. These findings update our understanding of halophile ecosystems and the habitable limit of animals.

High entropy ceramics for applications in extreme environments

Compositionally complex materials have demonstrated extraordinary promise for structural robustness in extreme environments. Of these, the most commonly thought of are high entropy alloys, where chemical complexity grants uncommon combinations of hardness, ductility, and thermal resilience. In contrast to these metal–metal bonded systems, the addition of ionic and covalent bonding has led to the discovery of high entropy ceramics (HECs). These materials also possess outstanding structural, thermal, and chemical robustness but with a far greater variety of functional properties which enable access to continuously controllable magnetic, electronic, and optical phenomena. In this experimentally focused perspective, we outline the potential for HECs in functional applications under extreme environments, where intrinsic stability may provide a new path toward inherently hardened device design. Current works on high entropy carbides, actinide bearing ceramics, and high entropy oxides are reviewed in the areas of radiation, high temperature, and corrosion tolerance where the role of local disorder is shown to create pathways toward self-healing and structural robustness. In this context, new strategies for creating future electronic, magnetic, and optical devices to be operated in harsh environments are outlined.

Phase-Tunable Molybdenum Boride Ceramics as an Emerging Sensitive and Reliable SERS Platform in Harsh Environments.

Traditional surface-enhanced Raman scattering (SERS) sensors rely heavily on the use of plasmonic noble metals, which have limitations due to their high cost and lack of physical and chemical stability. Hence, it is imperative to explore new materials as SERS platforms that can withstand high temperatures and harsh conditions. In this study, the SERS effect of molybdenum boride ceramic powders is presented with an enhancement factor of 5 orders, which is comparable to conventional noble metal substrates. The molybdenum boride powders synthesized through liquid-phase precursor and carbothermal reduction have β-MoB, MoB2 , and Mo2 B5 phases. Among these phases, β-MoB demonstrates the most significant SERS activity, with a detection limit for rhodamine 6G (R6G) molecules of 10-9 m. The impressive SERS enhancement can be attributed to strong molecule interactions and prominent charge interactions between R6G and the various phases of molybdenum boride, as supported by theoretical calculations. Additionally, Raman measurements show that the SERS activity remains intact after exposure to high temperature, strong acids, and alkalis. This research introduces a novel molybdenum boride all-ceramic SERS platform capable of functioning in harsh conditions, thereby showing the promising of boride ultrahigh-temperature ceramics for detection applications in extreme environments.

Additive manufacturing of refractory metals and carbides for extreme environments: an overview

Refractory metals and their carbides possess extraordinary properties when subjected to high temperatures and extreme environments. Consequently, they can act as key material systems for advancing many sectors, including space, energy and defence. However, it has been difficult to process these materials using the conventional routes of manufacturing. Additive manufacturing (AM) has shown a lot of potential to overcome the challenges and develop new material systems with tailored properties. This review provides a fundamental understanding of the challenges in the processing of refractory metals and their carbides, including microcracking, formation of brittle oxide phases and high ductile to brittle transition temperature (DBTT). We also highlight some of the novel approaches that have been taken to improve the processability of these challenging material systems using AM. These include in-situ reactive printing, ultrasonic vibration, laser beam shaping, multi-laser deposition and substrate pre-heating with a focus on microstructural changes to improve the properties of printed parts.

Combining Thermodynamics and Kinetics to Investigate the Corrosion of 3Cr Steel and HP-13Cr Stainless Steel in Extreme Oil-Gas Environments

ABSTRACT The corrosion behavior of 3Cr steel and HP-13Cr stainless steel (SS) under high temperature and CO2 or H2S pressure environments was investigated by immersion tests and multiple characterizations of corrosion films, and analyzed by combining the Pourbaix diagram and kinetic calculations. At 180 °C/3.8 MPa CO2, both 3Cr steel and HP-13Cr SS exhibited double-layered corrosion films, comprising a crystalline FeCO3 outer layer and an inner Cr2O3 and Cr(OH)3 layer. Furthermore, at 180 °C/3.8 MPa H2S, the corrosion films of both steels consist of an outer crystalline pyrrhotite and pyrite layer and an inner Cr2O3 and Cr(OH)3 layer. The corrosion resistance of 3Cr in H2S is inferior to that of HP-13Cr SS due to the influence of stress corrosion cracking but is close to that of HP-13Cr SS in CO2. Therefore, 3Cr steel could be considered a cost-effective alternative to HP-13Cr SS in CO2 environments.

Twins And Telomeres-In Space!

As part of the NASA Twins Study, our investigations related to telomeres and DNA damage responses (genome stability) during long-duration spaceflight have important implications for the health and performance of astronauts participating in exploration missions, as well as for long-term aging and disease risk outcomes. Together with the other Twins Study investigations, results will guide future studies and development of personalized medicine approaches for evaluating health effects for individual astronauts as we make our way back to the moon and beyond. Particularly as the number and diversity of space travelers and even space tourists increases over the coming years, identifying individual differences in response to the extreme environment, experiences and chronic exposures associated with space travel, exploration, and eventual habitation of other planets, represents a critical next step for ensuring future astronaut performance and health during, and improving disease and aging courses following, such missions. Ad astra!

Spacecraft Homography Pose Estimation with Single-Stage Deep Convolutional Neural Network.

Spacecraft pose estimation using computer vision has garnered increasing attention in research areas such as automation system theory, control theory, sensors and instruments, robot technology, and automation software. Confronted with the extreme environment of space, existing spacecraft pose estimation methods are predominantly multi-stage networks with complex operations. In this study, we propose an approach for spacecraft homography pose estimation with a single-stage deep convolutional neural network for the first time. We formulated a homomorphic geometric constraint equation for spacecraft with planar features. Additionally, we employed a single-stage 2D keypoint regression network to obtain homography 2D keypoint coordinates for spacecraft. After decomposition to obtain the rough spacecraft pose based on the homography matrix constructed according to the geometric constraint equation, a loss function based on pixel errors was employed to refine the spacecraft pose. We conducted extensive experiments using widely used spacecraft pose estimation datasets and compared our method with state-of-the-art techniques in the field to demonstrate its effectiveness.

Biomineralisation of corals inhabiting extreme and marginal environments

ABSTRACT Climate change is the primary threat to coral reefs, causing catastrophic coral mortality on a global scale. Stressors such as ocean acidification limit calcium carbonate availability needed to build skeletons. A wealth of research has shown that climate stressors impair the ability of coral to produce and maintain their skeletons, thereby disrupting functions critical to maintaining coral health as well as threatening the ecologically significant framework for reef building. There are natural marginal and extreme environments however, where coral reefs thrive despite unfavourable conditions. These habitats provide a natural long-term setting to examine the impact of multiple interacting climate change factors on corals and understand the adaptations required by corals to inhabit these conditions. We review studies of coral skeletogenesis in extreme and marginal environments, with a particular focus on mangrove habitats due to their natural fluctuations in temperature, pH and oxygen, analogous to those projected under climate change models. The changes in coral skeletal morphology under stress are described as are the techniques used to visualise these changes. In marginal and extreme environments, corals experience lower calcification rates and produce more porous, less robust skeletons whilst maintaining normal rates of linear extension, suggesting the integrity of coral skeletons are likely to be threatened under future ocean conditions. The biomineralisation processes of corals inhabiting extreme and marginal environments remains an underexplored area of research and has the potential to yield valuable insights into how corals might adapt to climate change and the mechanisms that underlie their resilience to global environmental change.

Southern Ocean food-webs and climate change: A short review and future directions

Food-webs are a critical feature of ecosystems and help us understand how communities will respond to climate change. The Southern Ocean is facing rapid and accelerating changes due to climate change. Though having evolved in an isolated and somewhat extreme environment, Southern Ocean biodiversity and food-webs are among the most vulnerable. Here, we review 1) current knowledge on Southern Ocean food-webs; 2) methods to study food-webs; 3) assessment of current and future impacts of climate change on Southern Ocean food-webs; 4) knowledge gaps; and 5) the role of Early Career Researchers (ECRs) in future studies. Most knowledge on Southern Ocean food-webs come from the pelagic environment, both at macro- and microbial levels. Modelling and diet studies of individual species are major contributors to the food-web knowledge. These studies revealed a short food-web, predominantly sustained by Antarctic Krill (Euphausia superba). Additionally, alternative pathways exist, involving other krill species, fish, and squid, which play equally important roles in connecting primary producers with top predators. Advantages and disadvantages of several techniques used to study Southern Ocean food-webs were identified, from the classical analyses of stomach contents, scats, or boluses to the most recent approaches such as metabarcoding and trophic-biomarkers. Observations show that climate change can impact the food-web in different ways. As an example, changes to smaller phytoplankton species can lengthen the food-web, increasing assimilation losses and/or changing nutrient cycles. Future studies need to focus on the benthic-dominated food-webs and the benthopelagic coupling. Furthermore, research during the winter season and below the ice-shelves is needed as these areas may play a crucial role in the functioning of this ecosystem. ECRs can play a significant role in advancing the study of Southern Ocean food-webs due to their willingness for interdisciplinary collaboration and proficiency in employing various methodologies, contributing to the construction of high-resolution food-webs.

Microstructural changes in GaN and AlN under 950 MeV Au swift heavy ion irradiation

The radiation hardness of GaN-based devices is a critical metric for applications in extreme environments. This study investigates the structural changes in GaN and AlN induced by swift heavy ion (SHI) irradiation, characteristic of space radiation environments. A multilayered GaN/AlN structure is exposed to 950 MeV Au ions at fluences of 1×1012 and 8×1012 ions/cm2. Subsequent post-irradiation characterization, including transmission electron microscopy and energy-dispersive x-ray spectroscopy, reveal no apparent amorphization across the entire sample. Notably, significant nanometer-sized cavities are observed in both GaN and AlN. The cavities in GaN exhibit an increase in number density and diameter with increasing SHI irradiation, with the average diameter progressing from 1.80 to 2.10 nm. In contrast, cavities in AlN appear considerably smaller. Molecular dynamics simulations, coupled with the inelastic thermal spike model, reproduce the presence of cavities in GaN and no cavities in the AlN structure. This difference is attributed to the faster heat dissipation and stronger bonding in AlN. Considering the overlapping of ion impacts at high fluences, simulations confirm the enlargement of cavity size in GaN. These findings contribute to a mechanistic understanding of the contrast in ion–matter interactions and induced microstructures between AlN and GaN under extreme ionizing radiation conditions. This disparity could potentially impact electronic performance through the formation of defect traps and interfacial strain fields.

Development, evaluation and stability mechanism of high-strength gels in high-temperature and high-salinity reservoirs

The high-temperature and high-salinity environment of the reservoir present a challenge for developing high-strength gels. In this study, a combination of acrylamide/2-acrylamido-2-methylpropanesulfonic acid (AM/AMPS) and partially hydrolyzed polyacrylamide (HPAM) was crosslinked with hydroquinone (HQ) and hexamethylenetetramine (HMTA) to prepare high-strength gels suitable for high-temperature and high-salinity reservoirs. The evaluation demonstrated that the gels exhibited exceptional strength, with a storage modulus exceeding 40 Pa. Gels containing more than 0.2 % crosslinker remained stable for over 120 days in brine with a salinity of 22 × 104 mg/L at 130 °C. Core flooding experimental evaluation revealed that the gel exhibited excellent plugging ability in fractures. Mechanisms of gel hardening and long-term stability in high-temperature and high-salinity environments were investigated by rheological testing, cryo-scanning electron microscopy (cryo-SEM) and Fourier transform infrared spectroscopy (FTIR) analysis. Results suggest that chelation between carboxylate groups in the gel and bivalent cations like calcium or magnesium increases mesh density, leading to hardening of the gel; aging also contributes to maintaining its strength while limiting syneresis due to AMPS presence and high mesh density, thus ensuring stability in extreme environments. The findings, although limited to laboratory-scale conditions and subject to potential variations in real time applications, still serve as a proof of concept for guiding the formulation of high-strength gels in reservoirs under extreme conditions.

Ethical and Medical Dilemmas of Extreme Tourism

Originally funded and experienced by millionaires and billionaires willing to spend hundreds of thousands or even millions for an extreme adventure where previously only explorers and scientists previously dared to go, extreme environment (i.e. polar, tundra, desert, space, space analog, deep ocean, mountaineering, nuclear meltdown sites etc.) tourism is becoming more common allowing more people to be exposed to increased dangers and risks that such tourists will be exposed to.  Some of those risks might be relatively minor such as possibly minor motion sickness.  Other risks, however, could include serious injury, such as in the case of the Titan submarine which imploded on a tour to the Titanic in June 2023, death.  The disaster, caused primarily by cost cutting measures and disregard of the danger from the company running the tour, which caused all 5 people on board to be killed instantaneously.  This presentation and paper will expand on previously published work on the medical and ethical dilemmas of space tourism as well as include an additional focus on tourism to other extreme environments including the neonate industry of space analog tourism where individuals pay to participate in a space analog mission at a hefty fee while potentially contributing or disrupting the legitimate scientific research going on such missions while still exposing themselves to additional risk which they might be unsuited for.  Further, this will discuss a few of the lesser known risks and concerns that have come more recently to light as well as a discussion as to not only if adults should be able to ethically, morally, and legally consent for their children during these high risk activities but whether or not, given the human brain does not fully develop until a person is in their mid-20s, how old should a person be in order to adequately understand and appropriately balance the risks and requirements of an extremely dangerous environment and be able to fully consent to the tourism venture’s risks.

Potential thermal constraints for sustainable industrial city: refined simulation and prediction of extreme urban heat island effect

Extreme urban heat islands (E-UHIs) have caused radical changes in urban climates. The lack of refined extreme thermal environment simulation models (ETESM) hinders research on the spatial evolution of E-UHI, which increases the uncertainty for managers to make sustainable decisions. Here, considering both the heating of industrial land and the heat transfer of surrounding facilities, a refined ETESM is constructed. Assuming four scenarios: maintain current trend (MtS), economically oriented scenario (EcS), environmentally oriented scenario (EnS), green transformation scenario (GtS), the future potential constraints of the E-UHI are simulated and predicted, thus determining the sustainable development decision in industrial city. The results indicate that there is significant spatial consistency between simulated temperature and actual temperature at both city scale (Pearson'r = 0.924, P<0.001) and industrial land scale (Pearson'r = 0.948, P<0.001). The average temperature under four scenarios shows: EcS>MtS>GtS>EnS. The average SST of EnS and GtS was 1.36℃ and 1.06℃ lower than that of MtS, respectively. Considering the dual constraints of environmental livability and economic sustainability, GtS is the best decision to achieve the sustainable development in industrial city. This simulation-driven study provides support for E-UHI mitigation and sustainable development of industrial city.

Impacts of Superalloys on the Surface Quality of Additively Manufactured Channels

Abstract Gas turbines feature many components that require superalloys capable of handling extreme thermal environments. Increasing the selection of materials available for these components is important to their use in these extremely high-temperature environments. This study investigated two recently developed materials intended to be used for additive manufacturing (AM), with one superalloy based on cobalt and the other on nickel. Sets of four test coupons were built using the materials, in addition to the commonly used Inconel-718, on multiple laser powder bed fusion machines. Several build conditions were varied between coupon sets, including coupon orientation, contour settings, and upskin and downskin treatment. Each set of test coupons featured four unique cooling designs to explore how different cooling technologies would be impacted by the variations in build conditions. After being built, coupons were computed tomography (CT) scanned to determine accuracy to design intent and quantify the surface roughness. The CT scans indicated that horizontally built test coupons had a significantly higher deviation from design intent and higher surface roughness than those built vertically. Results also indicated that the cobalt-based alloy consistently had a smoother surface quality with lower surface roughness compared to the nickel-based alloy. After geometric characterization, the cooling performance of the test coupons was measured experimentally. Pressure losses were found to correlate with increases in surface roughness; however, in some cases, the convective heat transfer did not increase proportionally to the pressure loss as a result of surface features significantly blocking the flow without proportionally increasing convective heat transfer.

A Study of a Cryogenic CuAlMn Shape Memory Alloy

In extreme temperature environments, a newly emerging engineering application involves both the active and passive control of structures using cryogenic shape memory alloys, which are smart materials able to recover high deformation below the freezing point. With the objective of carrying out new advances in this area, the present work aims to investigate the Cu-7.5Al-13.5Mn (wt.%) shape memory alloy. Thermal, microstructural, and thermomechanical analyses of as-cast and hot-rolled specimens were performed, taking into account the effects of annealing and solubilization. It was observed that the phase transition occurs at temperatures below 120 K and changes according to the thermo-mechanical path. Specifically, hot-rolling lowers the phase transition temperature range with respect to the as-cast condition–from 34 K to 23 K for Mf, and from 89 K to 80 K for Af. Additionally, when the annealing temperature rises, the phase transformation temperature increases as well, and the alloy loses its cryogenic features when heat treated above 473 K. Finally, loss factors of 0.06 and 0.088, which were respectively found in dynamic and static settings, validate the material’s good damping response.

Nuclear power plant pipeline detection robot based on a new radiation-proof material

Soft robots are gradually gaining recognition in recent years for their ability to work in extreme environments. However, radiation shielding is a major issue when designing soft robots for use in nuclear environments. In this paper we present an effective soft robot design and develop new radiation shielding materials that enable the robot to perform a variety of tasks in the complex pipelines of a nuclear power plant while being sufficiently radiation shielded. To achieve this, we used a mixture of silicone and lead powder with excellent radiation shielding capabilities and designed and built a soft robot prototype consisting of multiple pneumatic actuators and a resin frame. It is capable of moving through complex pipelines and performing inspection tasks, while also providing radiation shielding for the internal components of the robot. Finite element simulations and prototype experiments were then carried out to evaluate the robot's performance in various scenarios. Simulation results show that the soft robot is able to perform inspection of nuclear power plant pipelines efficiently and effectively. Furthermore, the radiation shielding provided by the radiation-proof material is effective in protecting the internal components of the robot from radiation exposure. In conclusion, we have successfully developed a soft robot prototype that is capable of performing pipeline inspections in extreme environments such as nuclear power plants, while providing adequate radiation shielding. The proposed approach can be extended to other soft robotics applications in the nuclear environment and has the potential to improve the safety and efficiency of nuclear power plant operations.

Human infrastructures correspond to higher Adélie penguin breeding success and growth rate.

Anthropogenic activities generate increasing disturbance in wildlife especially in extreme environments where species have to cope with rapid environmental changes. In Antarctica, while studies on human disturbance have mostly focused on stress response through physiological and behavioral changes, local variability in population dynamics has been addressed more scarcely. In addition, the mechanisms by which breeding communities are affected around research stations remain unclear. Our study aims at pointing out the fine-scale impact of human infrastructures on the spatial variability in Adélie penguin (Pygoscelis adeliae) colonies dynamics. Taking 24 years of population monitoring, we modeled colony breeding success and growth rate in response to both anthropic and land-based environmental variables. Building density around colonies was the second most important variable explaining spatial variability in breeding success after distance from skua nests, the main predators of penguins on land. Building density was positively associated with penguins breeding success. We discuss how buildings may protect penguins from avian predation and environmental conditions. The drivers of colony growth rate included topographical variables and the distance to human infrastructures. A strong correlation between 1-year lagged growth rate and colony breeding success was coherent with the use of public information by penguins to select their initial breeding site. Overall, our study brings new insights about the relative contribution and ecological implications of human presence on the local population dynamics of a sentinel species in Antarctica.

The Expanding Diversity of Viruses from Extreme Environments.

Viruses are nonliving biological entities whose host range encompasses all known forms of life. They are deceptively simple in description (a protein shell surrounding genetic material with an occasional lipid envelope) and yet can infect all known forms of life. Recently, due to technological advancements, viruses from more extreme environments can be studied through both culture-dependent and independent means. Viruses with thermophilic, halophilic, psychrophilic, and barophilic properties are highlighted in this paper with an emphasis on the properties that allow them to exist in said environments. Unfortunately, much of this field is extremely novel and thus, not much is yet known about these viruses or the microbes they infect when compared to non-extremophilic host-virus systems. With this review, we hope to shed some light on these relatively new studies and highlight their intrinsic value.

The right stuff: Salutogenic and pathogenic responses over a year in Antarctica

IntroductionEver since the first human reached the South Pole, studies have sought to explore the impact of an isolated, confined, and unusual environment on human adaptation. The findings have highlighted both negative and salutogenic effects on crews. Although several studies have focused on adaptation in the polar regions, we still do not fully understand its mechanisms. Thus, the objectives of the present study are: (1) to investigate the impact of a one-year stay in Antarctica on health adaptation; and (2) to assess recovery from this experience two days later. MethodSeventeen healthy participants were recruited to stay for one year at the French Dumont d’Urville station in Antarctica. Psychological, physiological, and exteroceptive measures were recorded on the day of arrival at the station (baseline), during each quarter of the wintering season (M4, M7, M10, M12), and two days after the return to the continent (D+2). Subjects were allocated to two groups according to their scores on the General Health Questionnaire at baseline, as follows: very limited or no existence of minor non-psychiatric or psychotic disorders (higher than normal, HN); and standard values for non-psychiatric or minor psychotic disorders within the general population (ordinary range, OR). ResultsOur results highlight both an adaptative response during the winter months, and pathogenic states during the last quarter of the mission and at recovery (D+2), which are still below normal values for psychological disorders and stress. The analysis of OR and HN groups during overwintering highlights a decrease in psychosensory responses, and thus poorer adaptation. ConclusionSpending a year in Antarctica no longer has harmful consequences (except during the third quarter of the mission), and the harshness of the environment in midwinter does not seem to be an aggravating factor for the winterers included in this study. Nevertheless, the General Health Questionnaire indicates two levels of adaptation during the mission. The latter observation suggests that there is a need to select the most-adaptable crews to maintain high performance during overwintering, and to prepare for the return to the continent. Taken together, our results contribute to a better understanding of adaptation in extreme environments, notably future dark space exploration.