Heat Bursts Research Articles

Mesonet-Based Climatology Of Severe Convective Winds in West Texas

Multiple studies have investigated the occurrence of severe convective winds and have increased our understanding of the forces driving severe winds and their spatial and temporal patterns. Some of the data used in studies have come from airport stations maintained by the National Weather Service. Their standardization across the United States makes them ideal for research, but they are limited in their distribution. This study aims to create a climatology of severe convective winds in West Texas using a mesoscale network (“mesonet”). Like their ASOS (Automated Surface Observing System) counterparts, these stations are standardized and well maintained. This study provides a 15-year climatology of severe convective wind gusts measured by the West Texas Mesonet (WTM). After extracting and manually verifying the measured gusts from over 30 WTM stations, both spatial and temporal distributions are presented. While temporal patterns in the gust distribution generally matched previous research, the high spatial resolution of the mesonet elucidated differences across a regional escarpment known as the Caprock. Comparison with regional AWOS / ASOS stations also revealed potential effects of a larger urban area. In addition to gust data, thermodynamic characteristics and rainfall accumulations associated with each gust were also investigated. In doing so, a substantial contribution from dry thunderstorm outflow winds and heat bursts to the production of regional severe wind was documented.

Anomalous heat generation that cannot be explained by known chemical reactions produced by nano-structured multilayer metal composites and hydrogen gas

Anomalously large heat generation phenomena that cannot be explained by any known chemical processes were discovered: Ni-based nano-structured multilayer metal composites were preloaded with hydrogen gas and heated rapidly to diffuse hydrogen and trigger the heat generation reaction. Maximum energy released per total hydrogen absorption was over 10 keV H–1 and no gamma rays or neutrons, which are harmful to the human body, were observed. It is possible to intentionally induce the heat burst phenomenon, which can increase the amount of heat generated without any new energy input. This can be applied to reaction control as well as to improving the accuracy of heat generation evaluation. A common feature, that regions of very high oxygen concentrations are observed in places, was observed in the heat-producing samples. At this time, however, the discussion of this oxygen concentration as nuclear in origin must exclude the possibility of many chemical processes.

Unravelling the jerky glide of dislocations in body-centred cubic crystals.

In situ straining tests in high purity α-Fe thin foils at low temperatures1 have demonstrated that crystal line defects, called dislocations, have a jerky type of motion made of intermittent long jumps of several nanometres. This observation conflicts with the standard Peierls mechanism for plastic deformation in body-centred cubic crystals, where the screw dislocation jumps are limited by inter-reticular distances, that is, distances of a few angstroms. Employing atomic-scale simulations, we show that although the short jumps are initially more favourable, their realization requires the propagation of a kinked profile along the dislocation line, which yields coherent atomic vibrations acting as travelling thermal spikes. Such local heat bursts favour the thermally assisted nucleation of new kinks in the wake of primary ones. The accumulation of new kinks leads to long dislocation jumps like those observed experimentally. Our study constitutes an important step towards predictive atomic-scale theory for materials deformation.

Thermodynamics of amyloid formation

AbstractBackgroundIs amyloid formation an exothermic process with the potential to damage brain tissue by local hyperthermia? In our study we aim to find answers to the above question. Several proteins, i.e. lysozyme and amyloid‐β peptide, known to form amyloid structures are investigated primarily by differential scanning calorimetry (DSC) in order to determine their thermodynamic properties.MethodExperiments in DSC are complemented by a set of other biophysical methods in order to clarify molecular parameters for the evaluation of the heat capacity measurements.ResultFor this purpose a seeded amyloid formation assay has been designed. In this assay the structural conversion of a given amount of monomeric protein is accelerated and synchronized by the addition of preformed amyloid fibril fragments to result in reproducible heat bursts caused by amyloid formation.ConclusionFirst results are reported and the measured enthalpies are related to known enthalpies from protein structural conversion processes.

Sustainable Potato Growth under Straw Mulching Practices

Extreme heat, droughts, pests, diseases, and short bursts of heavy rain make potato production unsustainable. This unfavorable environment negatively affects potato productivity and yield levels. Within the next few years, conditions will likely deteriorate even more. In potato cultivation, straw mulching has been shown to increase yields by promoting the growth of beneficial bacteria in the soil. Mulching improves soil humidity, decreases transpiration, and cools the soil in dry and hot regions. There is a global decline in potato yields per hectare due to poor nutrient management, moderately humid years, and high disease pressure caused by Phytophthora infestans and Alternaria species. Farmers must take cultivation measures to achieve economic efficiency and adequate yields. A range of practices contributes to better potato yields and productivity, such as the use of appropriate fungicides, planting high-yielding varieties, and increasing row spacing. These practices complicate cultivation and affect profits. Furthermore, inorganic nitrogen in the soil regularly causes acidification, eroding soil fertility. As a result of land preparation, straw residues from rice and maize are collected from the field and destroyed or burned, which depletes nutrients and pollutes the air. Returning these residues to the soil, however, can improve its quality. Integrating rice and maize straw mulching into potato cultivation practices can enhance agricultural sustainability, productivity, and yield. This review will focus on using rice and maize straw mulching in cultivating potatoes. Straw mulching promotes sustainable potato growth, increasing productivity and quality while minimizing reliance on chemical inputs. Such practices can mitigate the need for synthetic fertilizers to enhance sustainable agriculture, ensure long-term growth, improve soil health, increase yields, and promote sustainable agriculture.

Pollen Germination and Tube Growth in Northern Highbush Blueberry are Inhibited by Extreme Heat

The increasing intensity and frequency of extreme heat events threaten crop productivity globally. Certain phases of plant reproduction necessary for fertilization are highly sensitive to extreme heat, particularly during pollen development, germination, and tube elongation. However, few studies have assessed the effects of extreme heat on pollen performance in perennial crop plants. To understand how northern highbush blueberry pollen responds to high temperatures, we quantified pollen germination and pollen tube growth in vitro using four commercially relevant cultivars (Bluecrop, Elliott, Jersey, and Liberty) in climate-controlled chambers. We also tested recovery from high heat in ‘Bluecrop’ to determine whether pollen tubes can still germinate and grow after short bursts of extreme heat. We found the highest proportion of germinated pollen tetrads and the greatest pollen tube growth at 20 and 30 °C, and the lowest levels at 10 and 40 °C, with nearly complete inhibition at 40 °C. Exposure to between 30 and 40 °C revealed significant reduction in pollen germination and tube growth above 35 °C across all cultivars and assessment times. Exposure to 37.5 °C for only 4 hours resulted in substantial reductions in pollen germination and pollen tube growth, even after pollen was moved to optimal conditions of 25 °C. Extreme heat exposure, even for a short duration, significantly limits blueberry pollen germination and tube development. This is expected to have cascading effects on fruit set and crop yield. The nonreversibility of the effects on pollen highlights the need to prevent fields reaching damaging temperatures by developing crop monitoring and management strategies to protect crops during bloom.

Managing Medical Authority: How Doctors Compete for Status and Create Knowledge by Daniel A. Menchik

Reviewed by: Managing Medical Authority: How Doctors Compete for Status and Create Knowledge by Daniel A. Menchik Gil Eyal Daniel A. Menchik. Managing Medical Authority: How Doctors Compete for Status and Create Knowledge. Princeton, N.J.: Princeton University Press, 2021. xvii + 305 pp. $29.95 (978-0-691-22354-4). The central characters in this book are cardiac electrophysiologists (EPs), a special brand of cardiologists who seek to regulate the heart and repair abnormal rhythms by implanting defibrillators and pacemakers, and by using ablation catheters to burn or cool parts of the heart. Among EPs there are some who enjoy authority as standard-setters, and others who are merely clinicians. Both participate in a common occupational project that itself needs to secure the authority of electro-physiology among other medicine specialties. Hence the book’s title. Menchik’s question is how do they—both individuals and the specialty as a whole—manage to secure this authority given the essential indeterminacy of what they do—they feed a tiny catheter two feet through a vein in order to reach the heart and there deliver a burst of heat that they hope will burn just the right amount of tissue to restore the heart to its normal rhythm. Menchik’s answer is complex and somewhat hard to piece together, but this is what I came up with: 1. Standard-setters are individuals who have developed a particular way of “organizing indeterminacy.” While burning part of the heart would seem to be “heroic medicine,” an EP observes that “most of the time you go in . . . you literally have greater than 90% chance that you are going to succeed” (p .85). 2. Standard-setters are extremely competitive with one another, but this competition, Menchik shows, plays an important role in building their authority since it leads to differentiation into niches (specific type of problems addressed by specific type of solutions). Standard-setters “lead from a niche” (p. 82), but under the constant scrutiny of peers, who are concerned that the standard-setter does not do anything too risky to hurt the overall authority of the occupational project. While the competition is normally healthy, it can sometime erupt, as Menchik shows, into “whisper campaigns,” especially at conferences (p. 212). 3. Organizing indeterminacy, however, is a collective effort. While EPs place enormous value on having “good hands,” Menchik convincingly shows that dexterity and “good hands” are the product of coordinated teamwork and the EP’s control of the social relations of the lab (p. 69). 4. These social relations, in fact, extend beyond the lab and include what Menchik calls “tethered venues.” These include, for example, the labs of trusted colleagues, with whom a standard-setter collaborates on clinical trials. These tend to be former mentees, who share with the standard-setter the particular way of organizing indeterminacy, and whom the standard-setter knows to have “good hands,” good judgment, and good control of their own lab. Hence, a crucial role in the creation of medical authority is played by the process of attracting fellows, training them, and then placing them [End Page 174] in their own labs. Successful fellows add to the prestige of the EP, but also contribute to the success of their shared methods and approaches (p. 78). 5. Another set of tethered venues are the practices of referring clinicians. The authority of standard-setters depends on carefully selecting patients that are a) challenging, so they can be wrote up as case reports; b) appropriate for the particular procedure honed by the EP, so something like a 90% success rate can be approximated. A network of relations with referring clinicians has to be carefully cultivated if a particular mode of organizing indeterminacy is to be successful. The referring clinician has to be relatively certain that their patient will benefit from the referral, and the EP has to be relatively certain that the referred patient is the right one. In a fascinating chapter about the introduction of a bed management program at the hospital he observed, Menchik shows how it disrupted this network of relations since now EPs could no longer count on always having a few open beds for these carefully selected patients...

Mechanism of Solar Activity Triggering Earthquakes and Volcanos: Consequence of Whole-Earth Decompression Dynamics

Recently published scientific evidence implies that activities on the sun cause earthquakes and volcanic eruptions on Earth. However, the geophysical basis is inexplicable within the currently popular, but flawed geoscience paradigms. However, the mechanism of solar activity provoking earthquakes and volcanic eruptions follows logically from Whole-Earth Decompression Dynamics. Here I disclose the mechanism for changes in solar weather triggering earthquakes and volcanoes which operates as a multi-stage amplifier: A change in the charged particle flux impinging the Earth’s magnetic field induces electric current into the georeactor, which causes ohmic heating, which disrupts sub-shell convection, which results in extra uranium settling-out, which causes a burst of nuclear fission energy, which replaces some of the lost heat of protoplanetary compression, which causes a burst in whole-Earth decompression, which results in a burst of heat emplaced at the base of the crust and/or Earth’s surface experiencing a bit of decompression-driven movement, the extent of which is a function of the degree of sub-shell convection disruption.

Local Air‐Sea Interactions at Ocean Mesoscale and Submesoscale in a Western Boundary Current

AbstractWe present results from a new, global, high‐resolution (∼3‐km for ocean and ∼6‐km for atmosphere) realistic earth system simulation. This simulation allows us to examine aspects of small‐scale air‐sea interaction beyond what previous studies have reported. Our study focuses on recurring intermittent wind events in the Gulf Stream region. These events induce local air‐sea heat fluxes above Sea Surface Temperature (SST) anomalies with horizontal scales smaller than 500‐km. In particular, strong latent heat bursts above warm SST anomalies are observed during these wind events. We show that such wind events are associated with a secondary circulation that acts to fuel the latent heat bursts by transferring dry air and momentum down to the surface. The intensity of this secondary circulation is related to the strength of small‐scale SST fronts that border SST anomalies. The study of such phenomena requires high‐resolution in both the atmospheric and oceanic components of the model.

Advances in the interventional management of neuropathic pain

The management of neuropathic pain, defined as pain as a result of a lesion or disease in the somatosensory nervous system, continues to be researched and explored. As conventional methods demonstrate limited long-term efficacy, there is a significant need to discover therapies that offer both longitudinal and sustained management of this highly prevalent disease, which can be offered through interventional therapies. Tricyclic antidepressants (TCAs), gabapentinoids, lidocaine, serotonin norepinephrine reuptake inhibitors (SNRIs), and capsaicin have been shown to be the most efficacious pharmacologic agents for neuropathic pain relief. With respect to infusion therapies, the use of intravenous (IV) ketamine could be useful for complex regional pain syndrome, fibromyalgia, and traumatic spinal cord injury. Interventional approaches such as lumbar epidurals are a reasonable treatment choice for up to 3 months of pain relief for patients who failed to respond to conservative treatment, with a “B” strength of recommendation and moderate certainty. Neuroablative procedures like pulsed radiofrequency ablation work by delivering electrical field and heat bursts to targeted nerves or tissues without permanently damaging these structures, and have been recently explored for neuropathic pain relief. Alternatively, neuromodulation therapy is now recommended as the fourth line treatment of neuropathic pain after failed pharmacological therapy but prior to low dose opioids. Finally, the intrathecal delivery of various pharmacologic agents, such as quinoxaline-based kappa-opioid receptor agonists, can be utilized for neuropathic pain relief. In this review article, we aim to highlight advances and novel methods of interventional management of neuropathic pain.

Pollen development in cotton (Gossypium hirsutum) is highly sensitive to heat exposure during the tetrad stage.

The development of gametes in plants is acutely susceptible to heatwaves as brief as a few days, adversely affecting pollen maturation and reproductive success. Pollen in cotton (Gossypium hirsutum) was differentially affected when tetrad and binucleate stages were exposed to heat, revealing new insights into the interaction between heat and pollen development. Squares were tagged and exposed to 36/25°C (day/night, moderate heat) or 40/30°C (day/night, extreme heat) for 5 days. Mature pollen grains and leaves were collected for physiological and proteomic responses. While photosynthetic competence was not compromised even at 40°C, leaf tissues became leakier. In contrast, pollen grains were markedly smaller after the tetrad stage was exposed to 40°C and boll production was reduced by 65%. Sugar levels in pollen grains were elevated after exposure to heat, eliminating carbohydrate deficits as a likely cause of poor reproductive capacity. Proteomic analysis of pure pollen samples revealed a particularly high abundance of 70-kDa heat shock (Hsp70s) and cytoskeletal proteins. While short-term bursts of heat had a minor impact on leaves, male gametophyte development was profoundly damaged. Cotton acclimates to maxima of 36°C at both the vegetative and reproductive stages but 5-days exposure to 40°C significantly impairs reproductive development.

Reactivity Enhancement and Fabrication of Al-MoO3 Thermite Coating Using Ball Milling for Kinetic Spraying

Thermite materials, which are a pyrotechnic composition of metal and metal oxide, can create bursts of heat and high temperature thanks to an exothermic reduction–oxidation reaction. Fabrication methods of bulk thermite materials should preserve the reactivity of the materials and ensure a sufficient mixing of components. This work investigated the use of kinetic spraying and ball milling to overcome the limitations of existing preparation methods. Aluminum–molybdenum trioxide (Al-MoO3) was selected as thermite material. Ball milling and the fractions of metal and oxide were chosen as the variables of the study. The mechanical properties and reactivity of various powders and coatings were evaluated. The milled powders and coatings were successfully fabricated without reactivity loss by properly controlling the process parameters. The bond strength of the Al-MoO3 coating was however weaker than that of a pure Al coating because the MoO3 powder interrupted the intimate bonding between the Al splats. A reactivity analysis demonstrated that ball milling improved the reactivity of both the powders and the coatings by increasing the exothermic value, decreasing the reaction onset temperature, and decreasing the activation energy required for the thermite reaction. The mechanical properties and reactivity of coatings did not vary significantly with the MoO3 fraction.

Initiation of thermal runaway in Lithium-ion cells by inductive heating

An alternative thermal runaway initiation method for Li-ion cells has been developed based on the principles of inductive heating. Thermal runaway has been successfully triggered for different battery types, such as 3.1 Ah 18650 cylindrical cells, 39 Ah pouch and 94 Ah hard casing prismatic cells. A short burst of heat (few seconds) corresponding to only 1% of the electric energy of the cell is injected into the cell. The alternating electric field induces eddy current which heats up locally the conductive parts of the cell. Then through heat transfer the separator melts which results in internal short circuit. The initial short circuit develops to a hard internal short which triggers thermal runaway 10–20 s after the heater is switched off. The propagation of the initial internal short to thermal runaway can be observed visually by sparks and as open circuit voltage fluctuations. This newly discovered internal propagation may provide further insights into the failure mechanism of a single cell upon internal short and hence allow the development of new concepts to mitigate thermal propagation.

Heat Enhanced Follicular Delivery of Isotretinoin to the Skin.

The aim of this work was to evaluate the use of short durations of externally applied heat with chemical penetration enhancers to improve delivery of isotretinoin to the skin and in particular via the follicular route. A range of chemical penetration enhancers were screened for their ability to improve isotretinoin delivery into human skin with heat using infinite dose, Franz cell experiments conducted in a water bath at a higher temperature to simulate heated conditions. Following this a prototype external heating system was developed that provided short durations of heat and its ability to improve delivery of finite doses into the skin and hair follicles was assessed. The magnitude of the effect of heat on drug delivery was influenced by the choice of vehicle with changes in isotretinoin flux across skin ranging from not statistically significant to 25 fold increases with heat in the infinite dose studies. The prototype heating system provided significant increases in the total delivery of isotretinoin into the skin from an optimised vehicle. Drug distribution in the skin revealed significant increases in isotretinoin delivery to the hair follicles, and deeper skin layers, but not to the stratum corneum, providing strong evidence that the enhancement in delivery occurred mainly via the hair follicles. These data indicate that the use of short durations of heat combined with chemical penetration enhancers offers a valuable strategy for improving the delivery of drugs such as isotretinoin to the skin via the hair follicles. Graphical Abstract Schematic illustration of the sodium thiosulphate heating system on a Franz diffusion cell and the subsequent impact of a short burst of heat on the delivery of isotretinoin into human skin.

Predictions of DKIST/DL-NIRSP Observations for an Off-limb Kink-unstable Coronal Loop

Abstract Synthetic intensity maps are generated from a 3D kink-unstable flux rope simulation using several DKIST/DL-NIRSP spectral lines to make a prediction of the observational signatures of energy transport and release. The reconstructed large field-of-view intensity mosaics and single tile sit-and-stare high-cadence image sequences show detailed, fine-scale structure and exhibit signatures of wave propagation, redistribution of heat, flows, and fine-scale bursts. These fine-scale bursts are present in the synthetic Doppler velocity maps and can be interpreted as evidence for small-scale magnetic reconnection at the loop boundary. The spectral lines reveal the different thermodynamic structures of the loop, with the hotter lines showing the loop interior and braiding and the cooler lines showing the radial edges of the loop. The synthetic observations of DL-NIRSP are found to preserve the radial expansion, and hence the loop radius can be measured accurately. The electron number density can be estimated using the intensity ratio of the Fe xiii lines at 10747 and 10798 Å. The estimated density from this ratio is correct to within ±10% during the later phases of the evolution; however, it is less accurate initially when line-of-sight density inhomogeneities contribute to the Fe xiii intensity, resulting in an overprediction of the density by ≈30%. The identified signatures are all above a conservative estimate for instrument noise and therefore will be detectable. In summary, we have used forward modeling to demonstrate that the coronal off-limb mode of DKIST/DL-NIRSP will be able to detect multiple independent signatures of a kink-unstable loop and observe small-scale transient features including loop braiding/twisting and small-scale reconnection events occurring at the radial edge of the loop.

Liquid-gas hydrogen energy storage unit for the 15–17 K temperature range using an expansion volume at room temperature

In this paper, we describe a thermal energy storage unit able to absorb 400J between 15K and 17K using hydrogen as the working fluid. This prototype was studied to integrate a 300K-50mK (Nota: diferents units for the two numbers) cryogenic chain proposed for the ATHENA mission of European Space Agency (ESA) and its goal is to avoid the heat burst on the 15Kstage induced by the periodic regeneration of the 0.3K cooler. It consists of a small (≈17.5cm3) and light copper cell containing liquid hydrogen connected to an expansion volume (≈56L) at room temperature. When heat is delivered to this cell during the regeneration phase of the 0.3K cooler, the hydrogen evaporates and is stored in the gaseous state in the expansion volume. We show that, due to the relatively high latent heat of evaporation of H2, such a liquid-gas ESU seems to be the most compact and light solution with respect to the low temperature part. The tests performed to show the compliance of our device with ESA thermal requirements are described and analyzed. In particular, 400J are applied on this cell within 30min with a heating power peak reaching 1W during two minutes without exceeding 17K. We show that the results agree with a thermal model previously developed for similar liquid-gas ESU. A 21-h regeneration phase, consisting in the recondensation of H2 gas in the low temperature cell, follows this 400J absorption consisting in the recondensation of H2 gas in the low temperature cell. During this phase, the heat loads on the various thermal interfaces used to cool and condense the H2 gas were monitored to insure that they do not exceed the thermal budget. This test campaign allowed us to conclude that the low temperature part of this device seems compatible with thermal constraints needed for its integration in the proposed cryogenic chain.

Discovery of stationary operation of quiescent H-mode plasmas with net-zero neutral beam injection torque and high energy confinement on DIII-D

Recent experiments in DIII-D [J. L. Luxon et al., in Plasma Physics and Controlled Nuclear Fusion Research 1996 (International Atomic Energy Agency, Vienna, 1987), Vol. I, p. 159] have led to the discovery of a means of modifying edge turbulence to achieve stationary, high confinement operation without Edge Localized Mode (ELM) instabilities and with no net external torque input. Eliminating the ELM-induced heat bursts and controlling plasma stability at low rotation represent two of the great challenges for fusion energy. By exploiting edge turbulence in a novel manner, we achieved excellent tokamak performance, well above the H98y2 international tokamak energy confinement scaling (H98y2 = 1.25), thus meeting an additional confinement challenge that is usually difficult at low torque. The new regime is triggered in double null plasmas by ramping the injected torque to zero and then maintaining it there. This lowers E × B rotation shear in the plasma edge, allowing low-k, broadband, electromagnetic turbulence to increase. In the H-mode edge, a narrow transport barrier usually grows until MHD instability (a peeling ballooning mode) leads to the ELM heat burst. However, the increased turbulence reduces the pressure gradient, allowing the development of a broader and thus higher transport barrier. A 60% increase in pedestal pressure and 40% increase in energy confinement result. An increase in the E × B shearing rate inside of the edge pedestal is a key factor in the confinement increase. Strong double-null plasma shaping raises the threshold for the ELM instability, allowing the plasma to reach a transport-limited state near but below the explosive ELM stability boundary. The resulting plasmas have burning-plasma-relevant βN = 1.6–1.8 and run without the need for extra torque from 3D magnetic fields. To date, stationary conditions have been produced for 2 s or 12 energy confinement times, limited only by external hardware constraints. Stationary operation with improved pedestal conditions is highly significant for future burning plasma devices, since operation without ELMs at low rotation and good confinement is key for fusion energy production.

The influence of initial concentration of sulfuric acid on the degree of leaching of the main elements of ilmenite raw materials

There are a variety of incidents in the chemical industry, which occurred in bursts of heat at different stages of technological process and whose main cause was the reactive compounds. Consequences of unfortunate events were large loss of property and in some cases deaths. These events show how important are the conditions under which the process takes place and how important is knowledge about them. On the other hand, very important is the level of leaching of the main elements of the titanium raw materials, which influences the efficiency of the process. One of the important parameters affecting the safety and the degree of leaching of elements is the concentration of the sulfuric acid. In this research article, we propose parameter for determination of risk of thermal explosion in the reaction of sulfuric acid with titanium raw materials and results of investigation of sulfuric acid influence on the degree of leaching of the main elements. The investigations were realized for the Norwegian and Australian ilmenites analyzing the degree of leaching of elements such as TiO2, Fe2O3, MgO and MnO.

Intense Pulsed Light Annealing of Perovskite Solar Cells

Perovskite solar cells have produced significant interest in the scientific community. In the past 6 years, the perovskite solar cell has increased in efficiency from 3.8% to a staggering 20.1%. To add to the intrigue, the perovskite solar cell uses common low cost materials such as lead or tin and does not require the large manufacturing costs of using high temperatures and vacuum systems. Despite these advantages, the perovskite solar cell is still limited in efficiency due to the smaller crystal size of the perovskite material. The smaller crystal size of the perovskite material creates a more porous material with more grain boundaries that limit charge separation. Conventional methods of heating to enlarge the grain size of the perovskite crystals are limited due to the degradation reaction that converts the perovskite back to its precursor materials at 110 degrees Celsius. A newer technology called intense pulsed light is being used to generate light produced by a xenon plasma lamp at short millisecond pulses to create temperatures exceeding 500 degrees Celsius. The short bursts of heat enable higher temperatures to be reached by the perovskite crystals without degrading the material back to its precursors. Grain sizes have increased by over five times the grain sizes reported using conventional heating procedures.

40 K Liquid Neon Energy Storage Unit

A thermal Energy Storage Unit (ESU) could be used to attenuate inherent temperature fluctuations of a cold finger, either from a cryocooler working or due to suddenly incoming heat bursts. An ESU directly coupled to the cold source acts as a thermal buffer temporarily increasing its cooling capacity and providing a better thermal stability of the cold finger (“Power Booster mode”). The energy storage units presented here use an enthalpy reservoir based on the high latent heat of the liquid-vapour transition of neon in the temperature range 38 - 44K to store up to 900J, and that uses a 6 liters expansion volume at room temperature in order to work as a closed system. Experimental results in the power booster mode are described: in this case, the liquid neon cell was directly coupled to the cold finger of the working cryocooler, its volume (≈12 cm3) allowing it to store 450J at around 40K. 10W heat bursts were applied, leading to liquid evaporation, with quite reduced temperature changes. The liquid neon reservoir can also work as a temporary cold source to be used after stopping the cryocooler, allowing for a vibration-free environment. In this case the enthalpy reservoir implemented (≈24 cm3) was linked to the cryocooler cold finger through a gas-gap heat switch for thermal coupling/decoupling of the cold finger. We show that, by controlling the enthalpy reservoir's pressure, 900 Jcan be stored at a constant temperature of 40K as in a triple-point ESU.