Thick Ice Layer Research Articles

High-Quality Conductive Network Films Constructed from Carbon Nanotube/Carbon Nanofiber Composites via Electrospinning for Electrothermal Applications.

In this study, carbon nanotube (CNT)/carbon nanofiber (CNF) composite electrothermal films were prepared by electrospinning, and the effects of the CNT content and carbonization temperature on the electrothermal properties of the CNT/CNF composite films were investigated. The experimental results demonstrated that the conductivity of the CNT/CNF composite electrothermal film (0.006-6.89 S/cm) was directly affected by the CNT content and carbonization temperature. The electrothermal properties of the CNT/CNF positively correlated with the CNT content, carbonization temperature, and applied voltage. The surface temperature of CNT/CNF can be controlled within 30-260 °C, and continuously heated and cooled 100 times without any loss. The convective heat transfer with air is controllable between 0.008 and 31.75. The radiation heat transfer is controllable between 0.29 and 1.92. The prepared CNT/CNF exhibited a heat transfer efficiency of up to 94.5%, and melted a 1 cm thick ice layer within 3 min by thermal convection and radiation alone.

Superhydrophobic magnetically responsive fabric heater with triple thermal conversion for all-weather anti-icing/deicing

Incorporating innovative technology into functional fabrics extends their utility and addresses the daily challenges posed by fabric icing. Identifying effective anti-icing/deicing strategy is essential to mitigate the associated inconveniences. In this study, polypyrrole (PPy), Fe3O4 particles and polydimethylsiloxane (PDMS) are used as the raw materials to design an all-weather anti-icing and deicing functional fabric PDMS/Fe3O4/PPy@PET, presenting the photothermal/electrothermal and electromagnetic induction thermal functions. This functional fabric exhibits excellent hydrophobic performance with the contact angle of 152° and effectively delayed the droplet freezing for 181 s on a −10 ℃ cold table. The photothermal effect can reach an equilibrium temperature of 74.3 ℃ at 1 sunlight intensity and melt a 3 mm thick ice layer in 841 s. The electrothermal performance reaches to 72.2 ℃ at 10 V voltage and the ice layer is melted within 1436 s. The excellent electromagnetic induction thermal performance can reach to 71.4 ℃ in 5 min at 8 V voltage, and completely melt the ice layer in 444 s. In addition, the fabric offers excellent durability, abrasion resistance and UV resistance, allowing for long-term outdoor use. This opens up new ideas for the development of anti-icing and deicing functional fabric.

Formation and evolution of thermokarst landslides in the Qinghai-Tibet Plateau, China

Thermokarst landslide (TL) activity in the Qinghai-Tibet Plateau (QTP) is intensifying due to climate warming-induced permafrost degradation. However, the mechanisms driving landslide formation and evolution remain poorly understood. This study investigates the spatial distribution, annual frequency, and monthly dynamics of TLs along the Qinghai-Tibet engineering corridor (QTEC), in conjunction with in-situ temperature and rainfall observations, to elucidate the interplay between warming, permafrost degradation, and landslide activity. Through the analysis of high-resolution satellite imagery and field surveys, we identified 1298 landslides along the QTEC between 2016 and 2022, with an additional 386 landslides recorded in a typical landslide-prone sub-area. In 2016, 621 new active-layer detachments (ALDs) were identified, 1.3 times the total historical record. This surge aligned with unprecedented mean annual and August temperatures. The ALDs emerged primarily between late August and early September, coinciding with maximum thaw depth. From 2016 to 2022, 97.8 % of these ALDs evolved into retrogressive thaw slumps (RTSs), identified as active landslides. Landslides typically occur in alpine meadows at moderate altitudes and on gentle northward slopes. The thick ice layer near the permafrost table serves as the material basis for ALD occurrence. Abnormally high temperature significantly increased the active layer thickness (ALT), resulting in melting of the ice layer and formation of a thawed interlayer, which was the direct causing factor for ALD. By altering the local material, micro-topography, and thermal conditions, ALD activity significantly increases RTS susceptibility. Understanding the mechanisms of ALD formation and evolution into RTS provides a theoretical foundation for infrastructure development and disaster mitigation in extreme environments.

Transition from a mixotrophic/heterotrophic protist community during the dark winter to a photoautotrophic spring community in surface waters of Disko Bay, Greenland.

Unicellular eukaryotic plankton communities (protists) are the major basis of the marine food web. The spring bloom is especially important, because of its high biomass. However, it is poorly described how the protist community composition in Arctic surface waters develops from winter to spring. We show that mixotrophic and parasitic organisms are prominent in the dark winter period. The transition period toward the spring bloom event was characterized by a high relative abundance of mixotrophic dinoflagellates, while centric diatoms and the haptophyte Phaeocystis pouchetii dominated the successive phototrophic spring bloom event during the study. The data shows a continuous community shift from winter to spring, and not just a dormant spring community waiting for the right environmental conditions. The spring bloom initiation commenced while sea ice was still scattering and absorbing the sunlight, inhibiting its penetration into the water column. The initial increase in fluorescence was detected relatively deep in the water column at ~55 m depth at the halocline, at which the photosynthetic cells accumulated, while a thick layer of snow and sea ice was still obstructing sunlight penetration of the surface water. This suggests that water column stratification and a complex interplay of abiotic factors eventually promote the spring bloom initiation.

Robust and Superhydrophobic Polydimethylsiloxane/Ni@Ti3C2Tx Nanocomposite Coatings with Assembled Eyelash-Like Microstructure Array: A New Approach for Effective Passive Anti-Icing and Active Photothermal Deicing.

To solve the problem of ice condensation and adhesion, it is urgent to develop new anti-icing and deicing technologies. This study presented the development of a highly efficient photothermal-enhanced superhydrophobic PDMS/Ni@Ti3C2Tx composite film (m-NMPA) fabricated cost-effectively and straightforwardly. This film was fabricated utilizing PDMS as a hydrophobic agent, adhesive, and surface protector, while Ni@Ti3C2Tx as a magnetic photothermal filler innovatively. Through a simple spraying method, the filler is guided by a strong magnetic field to self-assemble into an eyelash-like microstructure array. The unique structure not only imparts superhydrophobic properties to the surface but also constructs an efficient "light-capturing" architecture. Remarkably, the m-NMPA film demonstrates outstanding superhydrophobic passive anti-icing and efficient photothermal active deicing performance without the use of fluorinated chemicals. The micro-/nanostructure of the film forms a gas layer, significantly delaying the freezing time of water. Particularly under extreme cold conditions (-30 °C), the freezing time is extended by a factor of 7.3 compared to the bare substrate. Furthermore, under sunlight exposure, surface droplets do not freeze. The excellent photothermal performance is attributed to the firm anchoring of nickel particles on the MXene surface, facilitating effective "point-to-face" photothermal synergy. The eyelash-like microarray structure enhances light-capturing capability, resulting in a high light absorption rate of 98%. Furthermore, the microstructure aids in maintaining heat at the uppermost layer of the surface, maximizing the utilization of thermal energy for ice melting and frost thawing. Under solar irradiation, the m-NMPA film can rapidly melt approximately a 4 mm thick ice layer within 558 s and expel the melted water promptly, reducing the risk of secondary icing. Additionally, the ice adhesion force on the surface of the m-NMPA film is remarkably low, with an adhesion strength of approximately 4.7 kPa for a 1 × 1 cm2 ice column. After undergoing rigorous durability tests, including xenon lamp weathering test, pressure resistance test, repeated adhesive tape testing, xenon lamp irradiation, water drop impact testing, and repeated brushing with hydrochloric acid and particles, the film's surface structure and superhydrophobic performance have remained exceptional. The photothermal superhydrophobic passive anti-icing and active deicing technology in this work rely on sustainable solar energy for efficient heat generation. It presents broad prospects for practical applications with advantages such as simple processing method, environmental friendliness, outstanding anti-icing effects, and exceptional durability.

Early-Stage Ice Detection Utilizing High-Order Ultrasonic Guided Waves.

Ice detection poses significant challenges in sectors such as renewable energy and aviation due to its adverse effects on aircraft performance and wind energy production. Ice buildup alters the surface characteristics of aircraft wings or wind turbine blades, inducing airflow separation and diminishing the aerodynamic properties of these structures. While various approaches have been proposed to address icing effects, including chemical solutions, pneumatic systems, and heating systems, these solutions are often costly and limited in scope. To enhance the cost-effectiveness of ice protection systems, reliable information about current icing conditions, particularly in the early stages, is crucial. Ultrasonic guided waves offer a promising solution for ice detection, enabling integration into critical structures and providing coverage over larger areas. However, existing techniques primarily focus on detecting thick ice layers, leaving a gap in early-stage detection. This paper proposes an approach based on high-order symmetric modes to detect thin ice formation with thicknesses up to a few hundred microns. The method involves measuring the group velocity of the S1 mode at different temperatures and correlating velocity changes with ice layer formation. Experimental verification of the proposed approach was conducted using a novel group velocity dispersion curve reconstruction method, allowing for the tracking of propagating modes in the structure. Copper samples without and with special superhydrophobic multiscale coatings designed to prevent ice formation were employed for the experiments. The results demonstrated successful detection of ice formation and enabled differentiation between the coated and uncoated cases. Therefore, the proposed approach can be effectively used for early-stage monitoring of ice growth and evaluating the performance of anti-icing coatings, offering promising advancements in ice detection and prevention for critical applications.

Sterilization effect and mechanism exploration of a mode‐combination method on Staphylococcus aureus in thick ice layers in a large sealed freezer

AbstractCold‐chain transport is a crucial cross‐regional transmission pathway for severe acute respiratory syndrome coronavirus 2 and other microorganisms. In this study, the mode‐combination method is adopted for sterilization in a 1.138 m3 freezer by mixing effluent gases of NOx and O3 mode air discharges. The mixed gas can effectively inactivate Staphylococcus aureus in 10 mm ice within 3 h, which significantly surpasses O3 gas. Moreover, the inactivation effect of the mixed gas can penetrate deep into ice, contrasting with the surface effect of O3 gas. This disparity is linked to the difference in penetration depth of strong oxidizing long‐lived reactive species. This study validates the sterilization efficacy of cold atmospheric plasma in practical cold‐chain environment, critical for curbing infectious disease transmission.

An effect of a snow cover on solar heating and melting of lake or sea ice

Solar radiative heating and melting of lake and sea ice is a geophysical problem that has attracted the attention of researchers for many years. This problem is important in connection with the current global change of the climate. Physical and computational models of the process are suggested in the paper. Analytical solutions for the transfer of solar radiation in light-scattering snow cover and ice are combined with numerical calculations of heat transfer in a multilayer system. The thermal boundary conditions take into account convective heat losses to the ambient air and radiative cooling in the mid-infrared window of transparency of the cloudless atmosphere. The study begins with an anomalous spring melting of ice on the large high-mountain lakes of Tibet. It was found that a thick ice layer not covered with snow starts to melt at the ice-water interface due to volumetric solar heating of ice. The results of the calculations are in good agreement with the field observations. The computational analysis showed a dramatic change in the process when the ice is covered with snow. A qualitative change in the physical picture of the process occurs when the snow cover thickness increases to 20–30 cm. In this case, the snow melting precedes ice melting and water ponds are formed on the ice surface. This is typical for the Arctic Sea in polar summer. Known experimental data are used to estimate the melting of sea ice under the melt pond. Positive or negative feedback related to the specific optical and thermal properties of snow, ice, and water are discussed.

Field-test performance of an ice-melting probe in a terrestrial analogue environment

Melting probes are a proven tool for the exploration of thick ice layers and clean sampling of subglacial water on Earth. Their compact size and ease of operation also make them a key technology for the future exploration of icy moons in our Solar System, most prominently Europa and Enceladus. For both mission planning and hardware engineering, metrics such as efficiency and expected performance in terms of achievable speed, power requirements, and necessary heating power have to be known.Theoretical studies aim at describing thermal losses on the one hand, while laboratory experiments and field tests allow an empirical investigation of the true performance on the other hand. To investigate the practical value of a performance model for the operational performance in extraterrestrial environments, we first contrast measured data from terrestrial field tests on temperate and polythermal glaciers with results from basic heat loss models and a melt trajectory model. For this purpose, we propose conventions for the determination of two different efficiencies that can be applied to both measured data and models. One definition of efficiency is related to the melting head only, while the other definition considers the melting probe as a whole. We also present methods to combine several sources of heat loss for probes with a circular cross-section, and to translate the geometry of probes with a non-circular cross-section to analyse them in the same way. The models were selected in a way that minimizes the need to make assumptions about unknown parameters of the probe or the ice environment.The results indicate that currently used models do not yet reliably reproduce the performance of a probe under realistic conditions. Melting velocities and efficiencies are constantly overestimated by 15 to 50% in the models, but qualitatively agree with the field test data. Hence, losses are observed, that are not yet covered and quantified by the available loss models. We find that the deviation increases with decreasing ice temperature. We suspect that this mismatch is mainly due to the too restrictive idealization of the probe model and the fact that the probe was not operated in an efficiency-optimized manner during the field tests. With respect to space mission engineering, we find that performance and efficiency models must be used with caution in unknown ice environments, as various ice parameters have a significant effect on the melting process. Some of these are difficult to estimate from afar.

CONSUMPTION OF MINE WATER BY WILD UNGULATES IN THE SOURCES OF THE USSURI RIVER, ON THE TERRITORY OF THE NATIONAL PARK «CALL OF THE TIGER»

Link for citation: Panichev A.M., Baranovskaya N.V., Aramilev V.V., Chekryzhov I.Yu., Vakh E.A., Vetoshkina A.V., Lutsenko T.N., Strepetov D.A. Consumption of mine water by wild ungulates in the sources of the Ussuri river, on the territory of the national park «Call of the tiger». Bulletin of the Tomsk Polytechnic University. Geo Аssets Engineering, 2023, vol. 334, no. 7, рр. 111-121. In Rus. The relevance of the study is determined by the need to clarify the reason for the use of mineralized water by wild animals, which is typical for many areas of the world. The new knowledge is closely related to the geophagy problem, the solution of which opens a wide prospect of fundamental research in the fields of landscape biogeochemistry, ecology and medicine. Purpose: to study chemical composition of the mineralized mine water in the lake located on the territory of the out-of-operation tin-polymetallic ores concentrator dump in the upper Ussuri river which is being consumed actively by wild ungulates; to reveal number of animal visitors to the lake during an annual cycle; to reveal the reason of mine water consumption. Objects: ungulates visiting the lake with mine water; lake water and bottom sediments. Methods: estimation of visitation of the mine lake by animals by means of photographic traps; chemical composition determination: inductively coupled plasma mass spectrometry (ICP-MS) (Agilent 7700x spectrometer, Agilent Techn., USA); atomic emission spectrometry (spectrometer iCAP 7600 Duo); ion chromatography (LC-20 ion-liquid chromatograph, Shimadzu, Japan). Results. It was revealed that animals come to the lake uniformly throughout the year, except for the winter period, when the water is covered by a thick layer of ice. In high concentrations trace elements were found, including both elements with high toxicity (Cd and Pb) exceeding MAC for drinking water from 20 to 80 times and essential elements such as Fe, Mn, Cu, Zn, Co, Cr, Ni, Se, Li, which concentration either does not exceed MPC or exceeds it insignificantly. The concentration of REE, especially of the light subgroup, is also very high. The reason for mine water consumption by animals, most likely, is the high concentration of rare-earth elements of the light subgroup in it.

Small crater relaxation and ice abundance at high northern latitudes on Mars

The cold, northern high-latitudes around the Phoenix landing site feature a population of small and very shallow craters known as palimpsest craters or boulder halos that could give insight into the subsurface ice content of the region. Notably there is also a split in the population by the size of craters that feature blocky ejecta: the smallest crater sizes that are <200–350 m in diameter typically do not feature blocky ejecta, while craters larger than this size range do. This has been interpreted as there being a less consolidated layer of mainly ice that sits over a more consolidated layer containing more silicate material from which the larger craters are able to excavate the blocky ejecta. This work focuses on determining whether these 200 m - 1 km shallow craters could be indicative of topographic relaxation due to substantial ice in the subsurface, with goals to determine the subsurface structure and most importantly the amount of ice present through its abundance and depth extent. We use finite element modeling of axisymmetric simple craters, employing the most recent characterizations of solid-state creep for water ice, silicate-rich ice, and CO2 ice, to determine the timescales and magnitudes of relaxation accommodated by an icy single or multiple material layered subsurface to determine the environment's properties. Our models include a 35 m thick layer of pure ice (water, or water and CO2) over a mobile substrate of particulate rich water ice of variable thicknesses able to accommodate relaxation for larger crater sizes up to 1 km in diameter. Our findings demonstrate that relaxation is able to account for significant flattening of crater topography, though for smaller craters the relaxation is incomplete, leaving about half the depth. The accommodated relaxation of our modeled subsurface does imply associated increases in ice abundances of 4 to 10 times greater than is currently estimated for the region, dependent on the extent of the mobile layer.

Under-Ice Development of Silica-Scaled Chrysophytes with Different Trophic Mode in Two Ultraoligotrophic Lakes of Yakutia

Silica-scaled chrysophytes are a widespread group of microeukaryotes, an important component of aquatic habitats. They belong to different evolutionary lineages and they are characterized by the presence of siliceous scales, but differ in trophic mode. We studied the diversity of these organisms in different months of the ice cover period in two subarctic lakes of Yakutia, Labynkyr and Vorota. Silica-scaled chrysophytes, due to various trophic modes, have a competitive advantage in conditions of a long period of ice cover. Statistical analysis has shown the relationship between the relative abundance of mixotrophic and photoautotrophic representatives of silica-scaled chrysophytes with the thickness of the snow cover and the transparency of the ice. An increase in snow cover thickness and the process of melting ice with a decrease in its transparency reduce the relative abundance of photoautotrophic and mixotrophic species. Photoautotrophic representatives of silica-scaled chrysophytes begin to develop already in April, when a thick, solid, and transparent layer of ice and a small layer of snow were observed. During the research period, from April to June, the relative abundance of colorless heterotrophic silica-scaled chrysophytes genera Paraphysomonas and Lepidochromonas was more or less stable. A new species of Spiniferomonas heterospina sp. nov. has been discovered in Lake Labynkyr.

Liquid water on cold exo-Earths via basal melting of ice sheets

Liquid water is a critical component of habitability. However, the production and stability of surficial liquid water can be challenging on planets outside the Habitable Zone and devoid of adequate greenhouse warming. On such cold, icy exo-Earths, basal melting of regional/global ice sheets by geothermal heat provides an alternative means of forming liquid water. Here, we model the thermophysical evolution of ice sheets to ascertain the geophysical conditions that allow liquid water to be produced and maintained at temperatures above the pressure-controlled freezing point of water ice on exo-Earths. We show that even with a modest, Moon-like geothermal heat flow, subglacial oceans of liquid water can form at the base of and within the ice sheets on exo-Earths. Furthermore, subglacial oceans may persist on exo-Earths for a prolonged period due to the billion-year half-lives of heat-producing elements responsible for geothermal heat. These subglacial oceans, often in contact with the planet’s crust and shielded from the high energy radiation of their parent star by thick ice layers, may provide habitable conditions for an extended period.

Sterilization of Salmonella typhimurium and Staphylococcus aureus in different cold-chain environments by combining NO x mode and O3 mode air discharges

Cold-chain transport has been suggested to be an important means for the cross-regional transmission of pathogenic microorganisms. In this study, NO x mode and O3 mode air discharges were combined by mixing effluent gases for sterilization in several cold-chain environments. It was found that the mixed gas effectively inactivated Salmonella typhimurium and Staphylococcus aureus in 1–4 mm thick ice layers at different temperatures (−20/−40/−80 °C) within 10 min, which is a significantly stronger effect than that of the effluent gas of either the NO x mode or the O3 mode discharge alone. This can be attributed to the high-valence reactive nitrogen species such as N2O5. Our findings provide a promising sterilization strategy to curb the spread of infectious diseases in cold-chain environments.

Solar heating of ice-covered lake and ice melting

Solar heating of freshwater lakes covered with ice is an important geophysical problem that has attracted researchers for many years. The main experimental and theoretical results concern solar heat accumulation in water under the ice and convective heat transfer in deep lakes. At the same time, the model of radiative transfer both in light-scattering ice and in water is too simplified and insufficient for a correct description of heat transfer, including ice melting. The present work largely compensates for this deficiency. For the first time, it is shown that a thick layer of ice begins to melt at the ice-water interface, mainly due to solar heating of the ice rather than heat flux from warmer water. The results of calculations for mountain lakes like Ngoring Lake in the northeast of the Tibetan Plateau are presented. The computational data are in good agreement with the published field observations.

Daily variations in Western Greenland slush limits, 2000–2021

AbstractThe marginal areas of the Greenland ice sheet develop streams and lakes each summer, documenting that surface runoff of meltwater is a major component of ice-sheet mass balance. Here we map the slush limit, a proxy for the extent of surface runoff, using daily MODIS data for the years 2000–2021. We develop an automated algorithm capable of detecting daily slush limits, provided sufficient image quality. The algorithm is applied to the ice sheet's western flank (61.7 $^{\circ }$N to 76.5 $^{\circ }$N). We find significant increasing trends in maximum slush limits until the year 2012, but not thereafter. We show that the slush limit typically rises quickly early in the ablation season but stabilizes before melting ceases. The data provide evidence that upward migration of surface runoff in summer 2012 stopped early at the upper margin of the ice slabs. These thick and continuous ice layers are located close to the surface, in the firn, and impede percolation of melt into deeper pore space. Had the ice slabs extended higher, the summer 2012 provided sufficient energy to raise the slush limit by another $\sim$300 m in elevation.

A possible perchlorate-enabled mechanism for forming thick near surface excess ice layers; in the Amazonian regolith of Mars

We use the freezing point depressing magnesium and calcium perchlorates in Martian regolith to redistribute ground ice by residual liquid water migration following the initial emplacement of ground ice by vapour deposition. This residual liquid water is moved by forces generated by periodic surface temperatures that decay with depth in conjunction with the geothermal vertical temperature gradient. We examine the period means of the bulk water speeds with depth and the mean divergence of the bulk water speeds, which relates to the rate of change in ice content in the regolith. Silt and clay rich regoliths behave differently. In silty regolith, for the short 1.88 a period and for longer 50 ka (precession) and 120 ka (obliquity) temperature cycles, there is a mean movement of liquid perchlorate aqueous solution that results in formation of near surface excess ice layers. The excess ice formed by the seasonal 1.88a period is confined at high latitudes to the upper meter of regolith. For the longer periods, there is a well-defined surface temperature region where near surface thick (≥40 m) excess ice layers form; (from 192 K to 210 K). For mean surface temperatures <192 K no near surface thick excess ice layers formed, but deeper layers are predicted and followed. The formation of excess ice layers in silt near the surface is controlled by the relationship between the temperature cycles, geothermal gradient and the eutectic temperature of the perchlorate (eg. ~198 K for Ca and ~ 205 K for Mg perchlorate). At a given depth if the periodic temperature is below the eutectic then there is nearly no liquid water left and what there is has much higher viscosity. The sudden change in the liquid water amount and viscosity with temperature generates net average water speeds in silts that are two orders larger than in clays.

Experimental study and numerical simulation of sidewalk electrical heating for deicing and snow melting

ABSTRACT A test model were designed in a constant-temperature laboratory to investigate the thermal conductivity and ice melting effect of pavements with embedded carbon fibre heating wires (CFHWs). The results showed that under simulated winter environmental conditions, the surface temperature of the test piece exceeded the freezing point after heating for 122 min in temperature rise test.Meanwhile,under the same conditions, the 10 mm thick ice layer on the test piece surface in the ice melting test began to melt after heating for 330 min, and all the ice layer had melted after 6 h , indicating that the pavement with embedded CFHWs has good ice melting performance. Moreover, a finite element model for transient heat transfer analysis was established. Combined with the experiments, the relevant parameters of the numerical model were corrected to obtain a more accurate numerical model. The calculations prove that the arrangement spacing significantly impacts the efficiency of the sidewalk for snow melting; the ambient temperature variation will slightly reduce the average rate of temperature rise on the surface of the model; and the ice melting effect of the CFHW with back shape is better than the U shape and the broken line shape under the same circumstances.

Recent Advances in Gas Injection System-Free Cryo-FIB Lift-Out Transfer for Cryo-Electron Tomography of Multicellular Organisms and Tissues

Abstract:Cryo-electron tomography (cryo-ET) enables visualization of protein complexes within their native cellular environment at molecular resolution. Most cells and all tissues, however, are too thick to be imaged directly by transmission electron microscopy (TEM). Overcoming this limitation requires the production of thin biological sections called lamellae. The procedure to obtain lamellae of cells, either seeded or grown directly on electron microscopy grids, requires cryo-focused ion beam (cryo-FIB) milling to thin the samples. This method faces an additional challenge when dealing with tissues and multicellular organisms, as these samples must be high-pressure frozen, which embeds the sample in a thick layer of ice. Nonetheless, lamellae can still be prepared from such samples by extracting a small volume and transferring it to a receiver grid for lamella preparation, a process called lift-out. Here, we describe the available workflows to produce lamellae by lift-out at cryogenic conditions and recent developments in gas injection system (GIS)-free approaches to the lift-out transfer. These advances expand the applications of cryo-ET, enabling the investigation of tissues and whole organisms in situ at molecular resolution.

Assessment of Manufacturing Parameters for New 3D-Printed Heating Circuits Based on CNT-Doped Nanocomposites Processed by UV-Assisted Direct Write

This work consists of the development of an easy strategy to transform any structure into an efficient surface heater by the application of a low voltage over 3D printed nanocomposite circuits. To this end, the electrical conductivity and self-heating capabilities of UV-Assisted Direct Write 3D printed circuits doped with carbon nanotubes were widely explored as a function of the number of printed layers. Moreover, an optimization of the printing process was carried out by comparing the accuracy and printability obtained when printing with two different configurations: extruding and curing the ink in the same stage or curing the extruded ink in a second stage, after the whole layer was deposited. In this regard, the great homogeneity and repeatability of the heating showed by the four-layer printed circuits, together with their excellent performance for long heating times, proved their applicability to convert any structure to a surface heater. Finally, the deicing capability of the four-layer circuit was demonstrated, being able to remove a 2.5 mm thick ice layer in 4 min and 4 s.