Harsh Conditions Research Articles

Vacuum assisted desorption of sodium zirconate sorbent for enhancing cyclic stability in pre-combustion CO2 capture

Sodium zirconate (Na2ZrO3) is a promising material for pre-combustion CO2 capture due to its fast sorption kinetics and excellent cyclic stability at high temperatures under ideal condition (desorption in 100% N2). Still, there is a lack of study on the performance of Na2ZrO3 cyclic capture under harsh condition (desorption in high concentration CO2). In this study, Na2ZrO3 was prepared by wet-mixing and heated-drying, and the difference in the cyclic CO2 capture performance of the sample was compared between desorption under harsh condition and vacuum condition. The crystal structure of Na2ZrO3 was identified during the sorption-desorption cycles. The crystal structure was also modeled and simulated to analyze the reason for the superior capture performance from the monoclinic Na2ZrO3. It was found that the special interlocked and multilayered stacked structure of the monoclinic Na2ZrO3 allowed for high reactivity with CO2. It was found that high temperature solely had little help in the desorption of Na2ZrO3 under harsh condition, but vacuum condition promoted desorption of Na2ZrO3 in high fraction CO2, and vacuum desorption at 1000 °C-1050 °C resulted in Na2ZrO3 with both good capture performance and cycling stability. Vacuum desorption led to more complete reversion of Na2ZrO3 to the monoclinic state, benefiting for CO2 capture. This study attempted to simulate the harsh capture environments of real industrial applications and to explore the possibility of Na2ZrO3 as a carbon capture material for pre-combustion capture.

Rapid detection of nitrite and Listeria monocytogenes in food based on multiple simulated enzyme activities of Fe3O4-ZnO-MnO2 nanocomposites

Food safety has emerged as a paramount concern in global health, prompting innovative approaches to ensure the safety of people's sustenance. In this study, a novel strategy was devised to fabricate Fe3O4-ZnO-MnO2 hybrid nanobiocatalysts, which exhibited remarkable enzymatic activity surpassing that of Horseradish peroxidase (HRP) catalysis. It demonstrated exceptional proficiency in decomposing 3,3′,5,5′-tetramethylbenzidine (TMB) without the need for harsh reaction conditions or the aid of H2O2. We established colorimetric detection systems based on Fe3O4-ZnO-MnO2-TMB both for nitrite (NO2−) and Listeria monocytogenes (LM) in food. Impressively, the detection limit of nitrite reached an astonishingly low level of 0.022 mg L−1, and the detection limit for LM was determined to be 3.5 cfu mL−1. These compelling results unequivocally validate the potential of these hybrid nanobiocatalysts to fortify food safety measures. Moreover, they serve as a valuable reference for the colorimetric detection of diverse analytes and the simultaneous detection of multiple targets.

Non-noble Co supported on Beta framework for hydrogenolysis of biomass-derived 5-hydroxymethylfurfural to renewable biofuel 2,5-dimethylfuran

Selective transformation of biomass platform molecule 5-hydroxymethylfurfural (HMF) into biofuel 2,5-dimethylfuran (DMF) through hydrogenolysis path has attracted significant attention in the field of biomass catalytic conversion. In general, this process required supported noble catalysts under elevated temperature (423-533 K) and enough H2 pressure (1-4 MPa). Herein, Co/Beta-DA catalysts with various Co loadings of 5-20 wt% were post-synthesized through wet impregnation. Benefiting from the relatively open channel systems and strong metal-support interactions, the obtained 10Co/Beta-DA with ∼10 wt% Co contents facilitated the hydrogenation of C=O bonds and the cleavage of C-O bonds, which was efficient for the selective hydrogenolysis from HMF to DMF (Conv.HMF ≥ 99.9%, Sel.DMF ≥ 99.9%) under mild reaction conditions (H2 pressure, 1.0 MPa; temp., 423 K; time, 3 h). The innovative strategy of designing and preparing rational non-noble impregnated zeolite provided brand-new perspectives to solve the problems of high cost and harsh reaction conditions in the HMF hydrogenolysis process, which has the potential to convert biomass into renewable liquid fuels.

One-pot construction of all-in-one flexible asymmetrical supercapacitors for extreme-condition applications

All-in-one flexible energy storage devices hold great application potential in the flexible and wearable electronics by virtue of unique configuration, however, still face severe challenges including complex fabrication steps, single variety of symmetrical supercapacitors and limited scenario application. For the first time, we propose a facile one-pot approach to fabricate all-in-one flexible asymmetrical supercapacitors (AFASCs) through magnetic driving localization of magnetic FeOOH anode away from MnO2 cathode in the electrolyte containing ethylene vinyl alcohol copolymers toward multi-scenario application. Distinctly different from the reported all-in-one approaches, this one-pot approach dramatically simplifies fabrication steps and especially extends more variety of electroactive materials for asymmetrical supercapacitors and even aqueous battery systems. A well-integrated configuration without any interfaces forms in the FeOOH/MnO2 AFASCs with low interfacial resistance, high areal capacitance, good cyclic stability and remarkable energy density. Significantly, the FeOOH/MnO2 AFASCs achieve superhigh capacitance retention not only in long-term bending and twisting deformations, but also under various extreme conditions including cutting, rolling, hammering, puncturing, sewing, soaking and washing in the water, as well as low temperature. Furthermore, the FeOOH/MnO2 AFASCs are demonstrated to power wearable smart bracelet, health monitoring, intelligent positioning system and running pod. Those findings can open up a new approach for one-pot construction of all-in-one flexible energy storage devices to meet future needs of flexible and wearable electronic devices under harsh working conditions.

Field Evaluation of Raspberry Cultivars in North Dakota

In North Dakota, USA, harsh winter conditions cause considerable winter injury to many floricane fruiting raspberries. Short growing seasons in North Dakota inevitably result in an incomplete fruit harvest of primocane fruiting raspberries. In this study, the winter hardiness of six floricane fruiting raspberry and five primocane fruiting raspberry cultivars had been evaluated for multiple years since 2016. Results showed that five floricane cultivars (Prelude, Boyne, Killarney, Nova, and Encore) showed less than 20% buds damaged, whereas cultivar Amethyst had 20% to 50% buds damaged in the winter. Severe bud damage was observed in five primocane fruiting cultivars (Polana, Autumn Bliss, BP-1, Heritage, and Joan J) in which Polana had the least winter bud damage with significant variations among years, followed by Heritage, Joan J, and Autumn Bliss, and BP-1. No winter damage was observed of the root system. In addition, the fruit quality, cane height, and yield of the six floricane fruiting cultivars were evaluated. Results showed that ‘Killarney’ fruit was the largest (2.50 g per berry) followed by ‘Nova’ (2.35), ‘Encore’ (2.24), ‘Amethyst’ (2.12), ‘Prelude’ (1.94), and ‘Boyne’ (1.84). No significant differences in total soluble solid (TSS) among cultivars were observed except that the TSS of Prelude was significantly lower than the other five cultivars. The cane height of ‘Killarney’ was the shortest (75 cm), whereas ‘Amethyst’ grew the longest canes (129 cm). Prelude is the earliest ripening floricane cultivar (late June) with a short harvest duration (20 to 25 days). The fruit harvest of ‘Killarney’, ‘Boyne’, and ‘Nova’ started 3 to 5 days after ‘Prelude’ with a longer harvest duration (25 to 30 days). ‘Encore’ and ‘Amethyst’ were harvested from mid-late July to early-mid August. Yield estimation indicated that ‘Killarney’ and ‘Nova’ produced more berries than other cultivars.

Road Performance of Cold Repaired Asphalt Mixture with New Green Maintenance Materials

Cold patched asphalt mixture plays a crucial role in road maintenance, providing flexibility and the ability to quickly recover from harsh weather conditions. This article conducts in-depth research on the performance of cold patched asphalt mixture through multiple experiments, with special attention paid to the influence of diluent content and curing conditions on its performance. The experimental results show that using a mixture of green curing agents is feasible, and the diluent content is one of the main factors affecting the physical properties of cold patched asphalt. The optimal content of asphalt diluent was determined to be 25% through mass evaporation experiments and rotational viscosity experiments. Meanwhile, it was found that single component polyurethane prepolymers and SBS curing agents have a negative impact on the adhesion of cold patched asphalt, but have an improving effect on its strength, high-temperature resistance, and water stability. After comparing the performance of cold patched asphalt mixtures under different curing conditions, it was found that the performance of cold patched materials with long-term curing was better. Finally, this study determined the optimal dosage ratio of base asphalt, bio oil diluent, and single component polyurethane prepolymer as 100:25:12, providing technical support for the design and application of cold patched asphalt concrete pavement under high adverse weather conditions.

Prospect for recycling critical elements in combustion residues of coal, lignite, and biomass feedstocks

The combustion residues derived from coal, lignite, biomass, and spent wash could be recycled to extract critical elements required for energy transition. To recycle these elements from the combustion residues, it is necessary to understand their chemical mode of occurrence in the ash. This study presents the content of critical elements and their chemical mode of occurrence in coal, lignite, biomass, and incinerator ash. Lignite ash, rich in Ca and Si, offers Sc (31 mg/kg) and Nd (212 mg/kg), while coal ash, dominated by Si and Al, contains Ga (44.8 mg/kg). Biomass and spent wash ash, characterized by K, Ca, and S, present substantial potential for potash and Sc. Lignite ash primarily contains rare earth elements (REEs) in metal oxide-bound fractions, whereas in coal ash, the REEs are associated with the hard mullite or quartz phase. Biomass and incinerator ashes have significant water-soluble potash, and the Sc is associated with metal oxides. Green acids can extract critical elements from lignite, biomass, and incinerator ashes, but extracting from coal ash requires harsh conditions. Future research should concentrate on green extraction processes considering the chemical patterns of occurrence of critical elements.

Direct method for microscale manipulation at liquid-liquid interfaces in ionic liquid media with real-time electron microscopy observation

A deep understanding of the processes in soft matter systems with liquid-liquid phase boundaries is of particular importance for materials science, chemistry and life sciences. A vast variety of physicochemical techniques have been proposed for the study of interfacial properties of liquid systems. Among them, electron microscopy methods occupy an important place due to the possibility of direct observation of the sample areas of interest with high spatial resolution; however, the harsh conditions of the electron microscope chamber impose significant restrictions on the possibilities of observing and manipulating unprotected liquids and related soft systems. To overcome these difficulties, in this work, we developed a methodology for direct probing of liquid-liquid interfaces with simultaneous control of the process using electron microscopy. Practically relevant liquid mixtures based on vacuum-compatible ionic liquid (IL) with water additives were probed with micrometer accuracy in real time inside an electron microscope chamber, which made it possible to reveal the role of specific ions aggregation and electrostatic phenomena in the stabilization of liquid microdomains. To test the versatility of the proposed approach, the morphology of a typical IL/water mixture was examined using a series of electron microscopes of various configurations, and it was shown that the best level of contrast between two chemically related liquid phases can be obtained in the case of a cold field emission electron source in combination with an in-lens secondary electron detector, regardless of the specific instrument manufacturer.

Hydrogen production capabilities of lichens micro-ecosystem under extreme salinity, crystalline salt exposure, and simulated Mars-like conditions

This work aims to demonstrate the extremophilic behavior of the lichen Pleurosticta acetabulum at extreme salinities, while maintaining its metabolic capacity to produce hydrogen. Lichen is a special micro-ecosystem that includes mostly a fungus and a green alga or cyanobacterium, as well as a microbiome. The peculiarity of this symbiotic system is its ability to dry out completely and stay inactive to survive harsh conditions. Lichens that had been dehydrated for six months revived quickly when rehydrated, restoring their photosynthetic efficiency and ability to produce hydrogen. The lichen microbiome was crucial for hydrogen production, especially through dark fermentation. The experiments of this work showed that lichen during its exposure to different salinity conditions (0%NaCl – control, 3,5%NaCl – sea salt concentration, 36%NaCl – saturated salt concentration), but also after exposure to crystalline salt (100%NaCl) could maintain the structure and the functionality of its photosynthetic apparatus. This was tested using chlorophyll a fluorescence induction measurements. Based on the results of thermal conductivity gas chromatography (GC-TCD) for the determination of hydrogen production, it was shown that despite being exposed to extreme salinity conditions, lichens maintained its ability to produce hydrogen. The experimental combination of lichen exposure to extreme salinities (up to 100% NaCl), with an extreme atmosphere (100% CO2) and low atmospheric pressure (<10mbar), simulating Mars conditions, highlighted the functional potential of the lichen for survival in a Mars-like environment. This lichen’s ability to withstand extreme conditions and to produce large amounts of hydrogen, makes it a promising candidate for future biotechnological applications, even in challenging environments like Mars, opening new astrobiological and astrobiotechnological perspectives.

Highly Selective On‐Surface Dehydrogenative Aromatization of n‐Hexyl to Phenyl Substituents

AbstractDehydrogenative aromatization of alkyl substituents represents a powerful approach to aryl‐substituted functional molecules. However, the inertness of alkyl groups and the need for harsh reaction conditions accompanied by low product selectivity hamper its widespread applications. Here, we demonstrate the highly selective on‐surface thermal aromatization of n‐hexyl substituents on polycyclic aromatic hydrocarbons (PAHs) to their phenyl‐substituted analogues under mild conditions. After depositing two representative precursor molecules, n‐hexyl‐substituted hexaphenylbenzene (HPB‐Hex) and bianthryl octacarboxylic tetraimide (BATI‐Hex), onto a pre‐heated Au(111) substrate, dehydroaromatization of the peripheral n‐hexyl groups into phenyl rings occurs, following the planarization of hexaphenylbenzene and bianthryl core. This process involves sequential intramolecular C−C bond rotations, dehydrogenation, and cyclodehydrogenation reactions, yielding phenyl‐substituted hexabenzocoronene (HBC‐Ph) and bisanthene octacarboxylic tetraimides (BSTI‐Ph). The reaction sequences were monitored using scanning tunneling microscopy (STM) and bond‐resolved non‐contact atomic force microscopy (nc‐AFM), offering structural proof of both intermediates and final products. These experimental techniques were complemented by density functional theory (DFT) simulations, which facilitated the detection of crucial steps in the conversion of n‐hexyl to phenyl groups. Moreover, the effect of alkyl aromatization on the electronic properties of the newly formed aromatic hydrocarbons was elucidated using scanning tunneling spectroscopy (STS).

Innovative multi-trial breeding and genotype screening in triticale (x Triticosecale Wittmack) for enhanced stability under drought stress.

Triticale is a man-made crop produced by crossing wheat (Triticum aestivum) and rye (Secal cereal) with the aim of increasing the adaptability and potential production of its parental line (wheat) under environmental stresses and harsh conditions. Accordingly, the objectives of this study are as follow, a: compare different stability measurement methods regarding their suitability, b: identify most stable genotypes for cultivar release, and c: provide a freely available package in R programming language (named 'Stbidx') capable of exploiting all stability methods for similar studies. Accordingly, 30 triticale genotypes were evaluated for their stability and adaptability to changing environments during four consecutive years from 2016 to 2020 in different locations in Iran (one year in Zarghan, two years in Ghorveh, one year in Sanandaj) and under two different irrigation regimes (normal irrigation and water deficit stress conditions). All 30 triticale genotypes were cultivated in a randomized complete block design (RCBD) with three replications in each environment (12 environments: 6 trials in 2 conditions). Grain yield of triticale genotypes was measured and it applied to calculate all known stability indices (univariate methods) along with the meta-analysis models were evaluated in this study. Additionally, two novel techniques (Stability ID: SID and AMMI PC Value: APCV) were introduced and successfully tested for screening stable genotypes. These methods were introduced to improve and resolve the limitation of the previous stability methods. Meanwhile, heatmap analysis, as a proper data-mining technique, has been successfully applied for the first time to find stable genotypes in different environments in this study. The results clearly indicated a higher suitability of our introduced methods over previous multi-trials screening methods. Based on our methods and considering all environments, triticale genotypes ELTTCL21 (SID = 8.00; APCV = 28.12), ELTTCL25‌ (SID = 8.14; APCV = 30.02), ELTTCL30 (SID = 8.43; APCV = 17.00), ET-90-8 (SID = 14.00; APCV = 42.05), and Sanabad (SID = 10.57; APCV = 12.44) were among stable genotypes and they can be nominated as new cultivars. Additionally, for stress condition genotypes ELTTCL30 (stress: 380.6g/m2) and ELTTCL18 (stress: 360.79g/m2) and for normal condition genotypes ET-90-4 (normal: 849.4g/m2) and ELTTCL20 (normal:845g/m2) were respectively the most proper genotypes with the highest production to be considered for each condition separately.

Experimental Study and Prospects of Valorization of Jatropha Curcas Seeds into Biodiesel

Jatropha curcas L. is a promising oilseed plant for biodiesel given its oil content and its tendency to grow in harsh environmental conditions. In this study, we conducted experiments on the valorization of jatropha seeds into biodiesel in order to estimate the key parameters of the process and the properties of the obtained biodiesel. The results revealed that the molar ratio between triglycerides and methanol, catalyst concentration, and reaction temperature played an important role in the diesel yield. The biodiesel produced had physicochemical characteristics in line with international standards for diesel fuels, with combustion properties comparable to those of conventional diesel. This study shed light on the optimization of the process of valorization of jatropha curcas seeds into biodiesel and on the support of the potential as a renewable fuel source.

Structural Insights into Cold-Active Lipase from Glaciozyma antarctica PI12: Alphafold2 Prediction and Molecular Dynamics Simulation.

Cold-active enzymes have recently gained popularity because of their high activity at lower temperatures than their mesophilic and thermophilic counterparts, enabling them to withstand harsh reaction conditions and enhance industrial processes. Cold-active lipases are enzymes produced by psychrophiles that live and thrive in extremely cold conditions. Cold-active lipase applications are now growing in the detergency, synthesis of fine chemicals, food processing, bioremediation, and pharmaceutical industries. The cold adaptation mechanisms exhibited by these enzymes are yet to be fully understood. Using phylogenetic analysis, and advanced deep learning-based protein structure prediction tool Alphafold2, we identified an evolutionary processes in which a conserved cold-active-like motif is presence in a distinct subclade of the tree and further predicted and simulated the three-dimensional structure of a putative cold-active lipase with the cold active motif, Glalip03, from Glaciozyma antarctica PI12. Molecular dynamics at low temperatures have revealed global stability over a wide range of temperatures, flexibility, and the ability to cope with changes in water and solvent entropy. Therefore, the knowledge we uncover here will be crucial for future research into how these low-temperature-adapted enzymes maintain their overall flexibility and function at lower temperatures.

Spontaneous Generation of -CH2CN from Acetonitrile at the Air-Water Interface.

Acetonitrile (CH3CN) is considered a very stable molecule in aqueous solutions, and its deprotonation to produce strongly basic -CH2CN requires harsh conditions. CH3CN is also present in the atmosphere, but its chemical transformation pathway at the air-water interface is unknown. In this study, we discovered and verified the unprecedented spontaneous generation of -CH2CN from the CH3CN-H2O solution at the air-water interface of microdroplets, and revealed the indirect deprotonation mechanism of CH3CN by synergistic redox of •OH and electrons in the microdroplets through the capture of key intermediates and computational chemistry. In addition, the dynamic process of indirect deprotonation-protonation was also observed. The high reactivity of -CH2CN in the droplets was revealed via nucleophilic addition to acetone, benzaldehyde, and the parent CH3CN molecule. Furthermore, the -CH2CN generated in the microdroplets underwent a barrier-free nucleophilic addition reaction with CO2 to produce 2-cyanoacetic acid for CO2 fixation. The synergistic redox reaction process revealed in this study provides new insights into microdroplet chemistry, and the distinctive CH3CN reactions identified may provide new clues to unravel the mystery of the CH3CN transformation in the atmospheric environment.

Abstract A012: g3bp1-mediated stress granule formation drives melanoma initiation in zebrafish

Abstract Stress granules confer cancer cells the ability to withstand harsh biological conditions and impart tumorigenic translational states through mRNA sequestration. Despite advances in in vitro knowledge, mechanistic understanding of the endogenous influence of stress granules during tumorigenesis in vivo remains understudied. To address this, we use a zebrafish melanoma model where oncogenic human BRAF V600E is driven by the melanocyte master regulator mitfa in a p53 -/- background. Through vector-based genetic engineering, endogenous melanoma induction in these zebrafish can be developmentally staged from single cell to tumor. BRAF V600E ::p53 -/- melanocytes form a cancerized field (CF), from which a subset upregulate the melanocyte master regulator mitfa, creating a cancer precursor zone (CPZ). Transformation of CPZ cells to an embryonic, neural crest-like state facilitates their formation of an early tumor patch that inevitable develops into an overt tumor. Single cell RNAseq analysis of cells representing each melanoma stage showed that CPZ cells upregulate core stress granule markers, including g3bp1, tia1, tia1l, and nufip2. Immunostaining of g3bp1 in CF, CPZ, patch, and tumor cells revealed a significant induction of stress granules from the CF to CPZ transition (2 vs 10 stress granules/cell; N=3; p=0.034) that persists during the patch and tumor stage, indicating cell stress accompanies melanoma initiation and progression. Genetic disruption of g3bp1 through cell autonomous, melanocyte-specific CRISPR editing in zebrafish (N=10-13) causes delayed CPZ onset (P=0.012) and fewer CPZs to form (P=0.021). In turn, g3bp1-edited zebrafish have delayed tumor formation (P=0.026) and develop fewer tumors (P=0.006). To decipher the RNAs sequestered by stress granules during melanomagenesis, we performed RIPseq for G3BP1 in human A375 melanoma cells stressed with sodium arsenite. RNAs significantly bound to G3BP1 upon stress induction include major tumor suppressors, such as CDKN2A, RBM5, BIK, and RHOB. Together, these results suggest that endogenous g3bp1-mediated stress granule formation in melanoma initiating cells is tumorigenic in vivo and operates through the sequestration of tumor suppressive RNAs. Citation Format: Kyle D Drake, Emily Formato, Leonard Zon. g3bp1-mediated stress granule formation drives melanoma initiation in zebrafish [abstract]. In: Proceedings of the AACR Special Conference in Cancer Research: RNAs as Drivers, Targets, and Therapeutics in Cancer; 2024 Nov 14-17; Bellevue, Washington. Philadelphia (PA): AACR; Mol Cancer Ther 2024;23(11_Suppl):Abstract nr A012.

Supernatant of plant-associated bacteria potency against biofilms formed by foodborne pathogen and food spoilage bacteria.

Food products are often contaminated by pathogens and spoilage bacteria. Most of them can form biofilms, a community of cells embedded in protective extracellular matrix layers resistant to harsh conditions, including antibiotics. Therefore, alternative antibiofilm agents are required to overcome biofilm formation. This study aims to determine and quantify the antibiofilm activity of supernatants from plant-associated bacteria against biofilms of foodborne pathogen and food spoilage bacterium, namely Bacillus cereus and Bacillus subtilis. Plant-associated bacteria (PAB) have shown promising antibiofilm activities against biofilm-forming pathogens in previous studies. Thirteen PAB isolated from Ternate, Indonesia were used in this study. Supernatants of PAB were subjected to antimicrobial activity and quorum quenching detection, both using the well diffusion method. Four supernatants inhibited the growth of B. subtilis, but none affected the growth of B. cereus. Eight supernatants were able to disrupt the quorum sensing system of an indicator bacterium, wild-type Chromobacterium violaceum. Biofilm inhibition and destruction were quantified using 96-well microplates. The highest biofilm inhibition and destruction activities of PAB supernatants against each of B. cereus and B. subtilis biofilms were > 76%, and were later confirmed by light microscope and scanning electron microscope. Brine shrimp lethality assay (BSLA) was conducted and revealed that the selected PAB supernatants were non-toxic. The 16S rRNA gene of PAB were sequenced and they showed similarities to Bacillus, Priestia, and Chryseobacterium. Compounds in the supernatants were determined by GC-MS which revealed contents of fatty acids, ethyl esters, and diketopiperazines. Therefore, PAB supernatants have potential as antibiofilm agents against biofilm formed by Bacillus cereus and Bacillus subtilis.

Fluorspar to fluorochemicals upon low-temperature activation in water.

The dangerous chemical hydrogen fluoride sits at the apex of the fluorochemical industry, but the substantial hazards linked to its production under harsh conditions (above 300 degrees Celsius) and transport are typically contracted to specialists. All fluorochemicals for applications, including refrigeration, electric transportation, agrochemicals and pharmaceuticals, are prepared from fluorspar (CaF2) through a procedure that generates highly dangerous hydrogen fluoride1-5. Here we report a mild method to obtain fluorochemicals directly from fluorspar, bypassing the necessity to manufacture hydrogen fluoride. Acid-grade fluorspar (more than 97 per cent CaF2) is treated with the fluorophilic Lewis acid boric acid (B(OH)3) or silicon dioxide (SiO2), in the presence of oxalic acid, a Brønsted acid that is highly effective for Ca2+ sequestration. This scalable process carried out in water at low temperature (below 50 degrees Celsius) enables access to widely used fluorochemicals, including tetrafluoroboric acid, alkali metal fluorides, tetraalkylammonium fluorides and fluoro(hetero)arenes. The replacement of oxalic acid with sulfuric acid gave comparable results for B(OH)3, but was not as effective when the fluorophilic Lewis acid was SiO2. A similar process also works with the lower-purity metspar. The production of fluorochemicals directly from fluorspar offers the possibility of decentralized manufacturing-an attractive model for the fluorochemical industry. With the renewed interest in innovative methods to synthesize oxalic acid via carbon dioxide capture and biomass6,7, and the challenges posed by our dependence on fossil fuels for sulfur and therefore sulfuric acid supply8,9, our technology may represent a departure towards a sustainable fluorochemical industry.

Role of VapBC4 toxin-antitoxin system of Sulfolobus acidocaldarius in heat stress adaptation.

This research enhances our knowledge of toxin-antitoxin (TA) systems in archaea, specifically in the thermoacidophilic archaeon Sulfolobus acidocaldarius. TA systems are widespread in both bacterial and archaeal genomes, indicating their evolutionary importance. However, their exact functions in archaeal cellular physiology are still not well understood. This study sheds light on the complex roles of TA systems and their critical involvement in archaeal stress adaptation, including persistence and biofilm formation. By focusing on S. acidocaldarius, which lives in habitats with fluctuating temperatures that can reach up to 90°C, the study reveals the unique challenges and survival mechanisms of this organism. The detailed biochemical analysis of the VapBC4 TA system, and its crucial role during heat stress, provides insights into how extremophiles can survive in harsh conditions. The findings of this study show the various functions of the VapC4 toxin, including inhibiting translation, inducing persister-like cell formation, and regulating biofilm formation. This knowledge improves our understanding of TA systems in thermoacidophiles and has broader implications for understanding how microorganisms adapt to extreme environments.

Remote SOC and SOH Estimation of High Energy Lithium Batteries Based on Dual-Mode Extended Kalman Filter Algorithm

Lithium battery, as its main power source, needs to ensure the safety of drivers and passengers not only under some complex external conditions, but also under harsh use conditions, even when damaged. At some point throughout this process, it is required to evaluate the status of the battery itself in order to assure safe usage of the battery and to develop a more effective battery management plan. SOC, SOH, and condition of power are all variables that are commonly used to describe the state of a lithium battery (SOP). The ability of the battery to constantly provide or receive power, the remaining service the life cycle of the battery, and the ability of the battery to output or receive power promptly are all described by these three characteristics. In order to effectively evaluate the health status of batteries, this paper proposes a dual-mode extended Kalman filter (EKF) algorithm for the remote estimation of SOC and SOH of high-energy lithium batteries. In the estimating procedure, the open circuit voltage (OCV) is also included as a state variable in the iterative process, which allows for more accurate results. In this paper, the state space equation is established based on the first-order RC equivalent circuit model, and the battery state estimation and parameter identification are completed by using the double EKF (the dual extended Kalman filtering, DEKF) algorithm, resulting in the realization of the estimation of SOC and SOH.

Experimental investigation on high heat flux plasma parameters of HIT-PSI device in argon discharges

Abstract Researches on plasma-facing materials/components (PFMs/PFCs) have become a focus in magnetic confinement fusion studies, particularly for advanced tokamak operation scenarios. Similarly, spacecraft surface materials must maintain stable performance under relatively high temperatures and other harsh plasma conditions, making studies of their thermal and ablation resistance critical. Recently, a low-cost, low-energy-storage for superconducting magnets, and compact linear device, HIT-PSI, has been designed and constructed at Harbin Institute of Technology (HIT) to investigate the interaction between stable high heat flux plasma and PFMs/PFCs in scrape-off-layer (SOL) and divertor regions, as well as spacecraft surface materials. The parameters of the argon plasma beam of HIT-PSI are diagnosed using a water-cooled planar Langmuir probe and emission spectroscopy. As magnetic field rises to 2 T, the argon plasma beam generated by a cascaded arc source achieves high density exceeding 1.2×1021 m−3 at a distance of 25 cm from the source with electron temperature surpassing 4 eV, where the particle flux reaches 1024 m−2s−1, and the heat flux loaded on the graphite target measured by infrared camera reaches 4 MW/m2. Combined with probe and emission spectroscopy data, the transport characteristics of the argon plasma beam are analyzed.