Contribution of mechanical forces to structural synaptic plasticity:insights from 3D cellular motility mechanisms

Cells,tissues,and organs are constantly subjected to the action of mechanical forces from the extracellular environment-and the nervous system is no exception.Cell-intrinsic properties such as membrane lipid composition,abundance of mechanosensors,and cytoskeletal dynamics make cells more or less likely to sense these forces.Intrinsic and extrinsic cues are integrated by cells and this combined information determines the rate and dynamics of membrane protrusion growth or retraction(Yamada and Sixt,2019).Cell protrusions are extensions of the plasma membrane that play crucial roles in diverse contexts such as cell migration and neuronal synapse formation.In the nervous system,neurons are highly dynamic cells that can change the size and number of their pre-and postsynaptic elements(called synaptic boutons and dendritic spines,respectively),in response to changes in the levels of synaptic activity through a process called plasticity.Synaptic plasticity is a hallmark of the nervous system and is present throughout our lives,being required for functions like memory formation or the learning of new motor skills(Minegishi et al.,2023;Pillai and Franze,2024).

Cu-based materials for electrocatalytic CO_(2) to alcohols:Reaction mechanism,catalyst categories,and regulation strategies

Electrocatalytic CO_(2) reduction reaction(CO_(2)RR)technology,which enables carbon capture storage and resource utilization by reducing CO_(2) to valuable chemicals or fuels,has become a global research hotspot in recent decades.Among the many products of CO_(2)RR(carbon monoxide,acids,aldehydes and alcohols,olefins,etc.),alcohols(methanol,ethanol,propanol,etc.)have a higher market value and energy density,but it is also more difficult to produce.Copper is known to be effective in catalyzing CO_(2) to high valueadded alcohols,but with poor selectivity.The progress of Cu-based catalysts for the selective generation of alcohols,including copper oxides,bimetals,single atoms and composites is reviewed.Meanwhile,to improve Cu-based catalyst activity and modulate product selectivity,the modulation strategies are straighten out,including morphological regulation,crystalline surface,oxidation state,as well as elemental doping and defect engineering.Based on the research progress of electrocatalytic CO_(2) reduction for alcohol production on Cu-based materials,the reaction pathways and the key intermediates of the electrocatalytic CO_(2)RR to methanol,ethanol and propanol are summarized.Finally,the problems of traditional electrocatalytic CO_(2)RR are introduced,and the future applications of machine learning and theoretical calculations are prospected.An in-depth discussion and a comprehensive review of the reaction mechanism,catalyst types and regulation strategies were carried out with a view to promoting the development of electrocatalytic CO_(2)RR to alcohols.

Study on trifluoromethanesulfonic acid-promoted synthesis of daidzein: Process optimization and reaction mechanism

Daidzein has been widely used in pharmaceuticals,nutraceuticals,cosmetics,feed additives,etc.Its preparation process and related reaction mechanism need to be further investigated.A cost-effective process for synthesizing daidzein was developed in this work.In this article,a two-step synthesis of daidzein(Friedel–Crafts acylation and[5+1]cyclization)was developed via the employment of trifluoromethanesulfonic acid(TfOH)as an effective promoting reagent.The effect of reaction conditions such as solvent,the amount of TfOH,reaction temperature,and reactant ratio on the conversion rate and the yield of the reaction,respectively,was systematically investigated,and daidzein was obtained in 74.0%isolated yield under optimal conditions.Due to the facilitating effect of TfOH,the Friedel–Crafts acylation was completed within 10 min at 90℃ and the[5+1]cyclization was completed within 180 min at 25℃.In addition,a possible reaction mechanism for this process was proposed.The results of the study may provide useful guidance for industrial production of daidzein on a large scale.

Study of the reaction mechanism for preparing powdered activated coke with SO_(2)adsorption capability via one-step rapid activation method under flue gas atmosphere

In this study,the impact of different reaction times on the preparation of powdered activated carbon(PAC)using a one-step rapid activation method under flue gas atmosphere is investigated,and the underlying reaction mechanism is summarized.Results indicate that the reaction process of this method can be divided into three stages:stage I is the rapid release of volatiles and the rapid consumption of O_(2),primarily occurring within a reaction time range of 0-0.5 s;stage II is mainly the continuous release and diffusion of volatiles,which is the carbonization and activation coupling reaction stage,and the carbonization process is the main in this stage.This stage mainly occurs at the reaction time range of 0.5 -2.0 s when SL-coal is used as material,and that is 0.5-3.0 s when JJ-coal is used as material;stage III is mainly the activation stage,during which activated components diffuse to both the surface and interior of particles.This stage mainly involves the reaction stage of CO_(2)and H2O(g)activation,and it mainly occurs at the reaction time range of 2.0-4.0 s when SL-coal is used as material,and that is 3.0-4.0 s when JJ-coal is used as material.Besides,the main function of the first two stages is to provide more diffusion channels and contact surfaces/activation sites for the diffusion and activation of the activated components in the third stage.Mastering the reaction mechanism would serve as a crucial reference and foundation for designing the structure,size of the reactor,and optimal positioning of the activator nozzle in PAC preparation.

The reaction mechanism and interfacial crystallization of Al nanoparticle-embedded Ni under shock loading

The shock-induced reaction mechanism and characteristics of Ni/Al system,considering an Al nanoparticle-embedded Ni single crystal,are investigated through molecular dynamics simulation.For the shock melting of Al nanoparticle,interfacial crystallization and dissolution are the main characteristics.The reaction degree of Al particle first increases linearly and then logarithmically with time driven by rapid mechanical mixing and following dissolution.The reaction rate increases with the decrease of particle diameter,however,the reaction is seriously hindered by interfacial crystallization when the diameter is lower than 9 nm in our simulations.Meanwhile,we found a negative exponential growth in the fraction of crystallized Al atoms,and the crystallinity of B2-NiAl(up to 20%)is positively correlated with the specific surface area of Al particle.This can be attributed to the formation mechanism of B2-NiAl by structural evolution of finite mixing layer near the collapsed interface.For shock melting of both Al particle and Ni matrix,the liquid-liquid phase inter-diffusion is the main reaction mechanism that can be enhanced by the formation of internal jet.In addition,the enhanced diffusion is manifested in the logarithmic growth law of mean square displacement,which results in an almost constant reaction rate similar to the mechanical mixing process.

Diffusion and reaction mechanism of limestone and quartz in fluxed iron ore pellet roasting process

The increase to the proportion of fluxed pellets in the blast furnace burden is a useful way to reduce the carbon emissions in the ironmaking process.In this study,the interaction between calcium carbonate and iron ore powder and the mineralization mechanism of fluxed iron ore pellet in the roasting process were investigated through diffusion couple experiments.Scanning electron microscopy with energy dispersive spectroscopy was used to study the elements’diffusion and phase transformation during the roasting process.The results indicated that limestone decomposed into calcium oxide,and magnetite was oxidized to hematite at the early stage of preheating.With the increase in roasting temperature,the diffusion rate of Fe and Ca was obviously accelerated,while the diffusion rate of Si was relatively slow.The order of magnitude of interdiffusion coefficient of Fe_(2)O_(3)-CaO diffusion couple was 10^(−10) m^(2)·s^(−1) at a roasting temperature of 1200℃for 9 h.Ca_(2)Fe_(2)O_(5) was the initial product in the Fe_(2)O_(3)-CaO-SiO_(2) diffusion interface,and then Ca_(2)Fe_(2)O_(5) continued to react with Fe_(2)O_(3) to form CaFe_(2)O_(4).With the expansion of the diffusion region,the sillico-ferrite of calcium liquid phase was produced due to the melting of SiO_(2) into CaFe_(2)O_(4),which can strengthen the consolidation of fluxed pellets.Furthermore,andradite would be formed around a small part of quartz particles,which is also conducive to the consolidation of fluxed pellets.In addition,the principle diagram of limestone and quartz diffusion reaction in the process of fluxed pellet roasting was discussed.

Decoding molecular mechanisms:brain aging and Alzheimer's disease

The complex morphological,anatomical,physiological,and chemical mechanisms within the aging brain have been the hot topic of research for centuries.The aging process alters the brain structure that affects functions and cognitions,but the worsening of such processes contributes to the pathogenesis of neurodegenerative disorders,such as Alzheimer's disease.Beyond these observable,mild morphological shifts,significant functional modifications in neurotransmission and neuronal activity critically influence the aging brain.Understanding these changes is important for maintaining cognitive health,especially given the increasing prevalence of age-related conditions that affect cognition.This review aims to explore the age-induced changes in brain plasticity and molecular processes,differentiating normal aging from the pathogenesis of Alzheimer's disease,thereby providing insights into predicting the risk of dementia,particularly Alzheimer's disease.

Pyroptosis,ferroptosis,and autophagy in spinal cord injury:regulatory mechanisms and therapeutic targets

Regulated cell death is a form of cell death that is actively controlled by biomolecules.Several studies have shown that regulated cell death plays a key role after spinal cord injury.Pyroptosis and ferroptosis are newly discovered types of regulated cell deaths that have been shown to exacerbate inflammation and lead to cell death in damaged spinal cords.Autophagy,a complex form of cell death that is interconnected with various regulated cell death mechanisms,has garnered significant attention in the study of spinal cord injury.This injury triggers not only cell death but also cellular survival responses.Multiple signaling pathways play pivotal roles in influencing the processes of both deterioration and repair in spinal cord injury by regulating pyroptosis,ferroptosis,and autophagy.Therefore,this review aims to comprehensively examine the mechanisms underlying regulated cell deaths,the signaling pathways that modulate these mechanisms,and the potential therapeutic targets for spinal cord injury.Our analysis suggests that targeting the common regulatory signaling pathways of different regulated cell deaths could be a promising strategy to promote cell survival and enhance the repair of spinal cord injury.Moreover,a holistic approach that incorporates multiple regulated cell deaths and their regulatory pathways presents a promising multi-target therapeutic strategy for the management of spinal cord injury.

Insights into kinetics and reaction mechanism of acid-catalyzed transesterification synthesis of diethyl oxalate

The catalytic performance of different acidic catalysts for diethyl oxalate synthesis from the one-step transesterification of dimethyl oxalate and ethanol was evaluated.The effects of different factors(e.g.,acidity,electron accepting capacity,cations type and crystalline water)on the catalytic activity of acidic catalysts were investigated respectively.It was proposed and confirmed that the transesterification reaction catalyzed by a Lewis acid(FeCl3)and a Bronsted acid(H2SO4)follows a first-order kinetic reaction process.In addition,the Lewis acid-catalyzed transesterification processes with different ester structures were used to further explore and understand the speculated reaction mechanism.This work enriches the theoretical understanding of acid-catalyzed transesterification reactions and is of great significance for the development of highly active catalysts for diethyl oxalate synthesis,diminishing the industrial production cost of diethyl oxalate,and developing downstream bulk or high-value-added industrial products.

Exploring the Cation Regulation Mechanism for Interfacial Water Involved in the Hydrogen Evolution Reaction by In Situ Raman Spectroscopy

Interfacial water molecules are the most important participants in the hydrogen evolution reaction(HER).Hence,understanding the behavior and role that interfacial water plays will ultimately reveal the HER mechanism.Unfortunately,investigating interfacial water is extremely challenging owing to the interference caused by bulk water molecules and complexity of the interfacial environment.Here,the behaviors of interfacial water in different cationic electrolytes on Pd surfaces were investigated by the electrochemistry,in situ core-shell nanostructure enhanced Raman spectroscopy and theoretical simulation techniques.Direct spectral evidence reveals a red shift in the frequency and a decrease in the intensity of interfacial water as the potential is shifted in the positively direction.When comparing the different cation electrolyte systems at a given potential,the frequency of the interfacial water peak increases in the specified order:Li+<Na^(+)<K^(+)<Ca^(2+)<Sr^(2+).The structure of interfacial water was optimized by adjusting the radius,valence,and concentration of cation to form the two-H down structure.This unique interfacial water structure will improve the charge transfer efficiency between the water and electrode further enhancing the HER performance.Therefore,local cation tuning strategies can be used to improve the HER performance by optimizing the interfacial water structure.

Exploring nitrogen reduction reaction mechanisms in electrocatalytic ammonia synthesis:A comprehensive review

The electrochemical nitrogen reduction reaction(eNRR)holds significant promise as a sustainable alternative to the conventional large-scale Haber Bosch process,offering a carbon footprint-free approach for ammonia synthesis.While the process is thermodynamically feasible at ambient temperature and pressure,challenges such as the competing hydrogen evolution reaction,low nitrogen solubility in electrolytes,and the activation of inert dinitrogen(N_(2))gas adversely affect the performance of ammonia production.These hurdles result in low Faradaic efficiency and low ammonia production rate,which pose obstacles to the commercialisation of the process.Researchers have been actively designing and proposing various electrocatalysts to address these issues,but challenges still need to be resolved.A key strategy in electrocatalyst design lies in understanding the underlying mechanisms that govern the success or failure of the electrocatalyst in driving the electrochemical reaction.Through mechanistic studies,we gain valuable insights into the factors affecting the reaction,enabling us to propose optimised designs to overcome the barriers.This review aims to provide a comprehensive understanding of the various mechanisms involved in eNRR on the electrocatalyst surface.It delves into the various mechanisms such as dissociative,associative,Mars-van Krevelen,lithium-mediated nitrogen reduction and surface hydrogenation mechanisms of nitrogen reduction.By unravelling the intricacies of eNRR mechanisms and exploring promising avenues,we can pave the way for more efficient and commercially viable ammonia synthesis through this sustainable electrochemical process by designing an efficient electrocatalyst.

Conversion of Lignin into Porous Carbons for High-Performance Supercapacitors via Spray Drying and KOH Activation: Structure-Properties Relationship and Reaction Mechanism

Lignin-derived porous carbons have emerged as promising electrode materials for supercapacitors.However,the challenge remains in designing and controlling their structure to achieve ideal electrochemical performance due to the complex molecular structure of lignin and its intricate chemical reactions during the activation process.In this study,three porous carbons were synthesized from lignin by spray drying and chemical activation with vary-ing KOH ratios.The specific surface area and structural order of the prepared porous carbon continued to increase with the increase of the KOH ratio.Thermogravimetric-mass spectrometry(TG-MS)was employed to track the molecular fragments generated during the pyrolysis of KOH-activated lignin,and the mechanism of the thermochemical conversion was investigated.During the thermochemical conversion of lignin,KOH facili-tated the removal of H2 and CO,leading to the formation of not only more micropores and mesopores,but also more ordered carbon structures.The pore structure exhibited a greater impact than the carbon structure on the electrochemical performance of porous carbon.The optimized porous carbon exhibited a capacitance of 256 F g-1 at a current density of 0.2 A g-1,making it an ideal electrode material for high-performance supercapacitors.

Oxidation behavior of ferrovanadium spinel particles in air:Isothermal kinetic and reaction mechanism

The oxidation behavior of ferrovanadium spinel(FeV_(2)O_(4)),synthesized via high-temperature solid-state reaction,was investigated using thermogravimetry,X-ray diffractometry,and X-ray photoelectron spectroscopy over the temperature range of 450–700℃.The results revealed that the oxidation process of FeV_(2)O_(4)can be divided into three stages with the second stage being responsible for maximum weight gain due to oxidation.Three classical methods were employed to analyze the reaction mechanisms and model functions for distinct oxidation stages.The random nucleation and subsequent growth(A_(3))kinetic model was found to be applicable to both initial and secondary stage.The third stage of oxidation was consistent with the three-dimensional diffusion,spherical symmetry(D_(3))kinetic mode.Both the model-function method and the model-free method were utilized to investigate the apparent activation energy of the oxidation reaction at each stage.It was found that the intermediates including Fe_(3)O_(4),VO_(2),V_(2)O_(3),and Fe_(2.5)V_(7.11)O_(16),played significant roles in the oxidation process prior to the final formation of FeVO_(4)and V_(2)O_(5)through oxidation of FeV_(2)O_(4).

Advances in the study of HOR reaction mechanisms under alkaline conditions

Hydrogen energy is an important energy carrier,which is an ideal choice to meet energy demand and reduce harmful gas emissions.The green recycling of hydrogen energy depends on water electrolysis and hydrogen fuel cells,which involves hydrogen oxidation reaction(HOR)and hydrogen evolution reaction(HER).The activity of HER/HOR in alkaline electrolyte,however,exhibits a significantly lower magnitude(2–3 orders)compared to that observed in an acidic medium,which hinders the development of alkaline water electrolysis and alkaline membrane fuel cells.Therefore,comprehending the characteristics of HOR/HER activity in alkaline electrolytes and elucidating its underlyingmechanismis a prerequisite for the designof advanced electrocatalysts.Based on this background,this reviewwill briefly summarize the explanations and controversies about the basic HOR mechanism,including bifunctional mechanismand hydrogen binding energy theory.Moreover,the crucial affecting factors of theHOR kinetics,such as dband center theory,interfacial water recombination,alkali metal cations and electronic effects,are discussed.Thus,based on the above theories,the design principle,catalytic performance,and latest progress ofHOR electrocatalysts are summarized.An outlook and future research perspectives of advanced catalysts for hydrogen energy recycling are addressed.This reviewis helpful to understand the latest development ofHORmechanismand design cost-effective and high-performance HOR electrocatalysts towards the production of clean renewable energies.

Oxidation behavior of FeV_(2)O_(4)and FeCr_(2)O_(4)particles in the air:Nonisothermal kinetic and reaction mechanism

High-temperature oxidation behavior of ferrovanadium(FeV_(2)O_(4))and ferrochrome(FeCr_(2)O_(4))spinels is crucial for the application of spinel as an energy material,as well as for the clean usage of high-chromium vanadium slag.Herein,the nonisothermal oxidation behavior of FeV_(2)O_(4)and FeCr_(2)O_(4)prepared by high-temperature solid-state reaction was examined by thermogravimetry and X-ray diffraction(XRD)at heating rates of 5,10,and 15 K/min.The apparent activation energy was determined by the Kissinger-Akahira-Sunose(KAS)method,whereas the mechanism function was elucidated by the Malek method.Moreover,in-situ XRD was conducted to deduce the phase transformation of the oxidation mechanism for FeV_(2)O_(4)and FeCr_(2)O_(4).The results reveal a gradual increase in the overall apparent activation energies for FeV_(2)O_(4)and FeCr_(2)O_(4)during oxidation.Four stages of the oxidation process are observed based on the oxidation conversion rate of each compound.The oxidation mechanisms of FeV_(2)O_(4)and FeCr_(2)O_(4)are complex and have distinct mechanisms.In particular,the chemical reaction controls the entire oxidation process for FeV_(2)O_(4),whereas that for FeCr_(2)O_(4)transitions from a three-dimensional diffusion model to a chemical reaction model.According to the in-situ XRD results,numerous intermediate products are observed during the oxidation process of both compounds,eventually resulting in the final products FeVO_(4)and V2O_(5)for FeV_(2)O_(4)and Fe_(2)O_(3)and Cr_(2)O_(3)for FeCr_(2)O_(4),respectively.

Promotional roles of ZrO_2 and WO_3 in V_2O_5-WO_3/TiO_2-ZrO_2 catalysts for NO_x reduction by NH_3:Catalytic performance,morphology,and reaction mechanism

V2O5/TiO2-ZrO2 catalysts containing various amounts of WO3 were synthesized.The catalyst morphologies,catalytic performances,and reaction mechanisms in the selective catalytic reduction of NOx by NH3 were investigated using in situ diffuse-reflectance infrared Fourier-transform spectroscopy,temperature-programmed reduction（TPR）,X-ray diffraction,and the Brunauer-Emmett-Teller（BET） method.The BET surface area of the triple oxides increased with increasing ZrO2 doping but gradually decreased with increasing WO3 loading.Addition of sufficient WO3 helped to stabilize the pore structure and the combination of WO3 and ZrO2 improved dispersion of all the metal oxides.The mechanisms of reactions using V2O5-9%WO3/TiO2-ZrO2 and V2O5-9%WO3/TiO2were compared by using either a single or mixed gas feed and various pretreatments.The results suggest that both reactions followed the Eley-Ridel mechanism;however,the dominant acid sites,which depended on the addition of WO3 or ZrO2,determined the pathways for NOx reduction,and involved[NH4^＋-NO-Bronsted acid site]^＊ and[NH2-NO-Lewis acid site]^＊ intermediates,respectively.NH3-TPR and H2-TPR showed that the metal oxides in the catalysts were not reduced by NH3 and O2did not reoxidize the catalyst surfaces but participated in the formation of H2O and NO2.

Mechanism for thermite reactions of aluminum/iron-oxide nanocomposites based on residue analysis

Sol-gel method was employed to combine Al and iron-oxide to form nanocomposites （nano-Al/xero-Fe2O3 and micro-Al/xero-Fe2O3）. SEM, EDS and XRD analyses were used to characterize the nanocomposites and the results indicated that nano-Al and micro-Al were compactly wrapped by amorphous iron-oxide nanoparticles （about 20 nm）, respectively. The iron-oxide showed the mass ratio of Fe to O as similar as that in Fe2O3. Thermal analyses were performed on two nanocomposites, and four simple mixtures （nano-Al＋xero-Fe2O3, nano-Al＋micro-Fe2O3, micro-Al＋xero-Fe2O3, and micro-Al＋micro-Fe2O3） were also analyzed. There were not apparent distinctions in the reactions of thermites fueled by nano-Al. For thermites fueled by micro-Al, the DSC peak temperatures of micro-Al/Xero-Fe2O3 were advanced by 68.1 ℃ and 76.8 ℃ compared with micro-Al＋xero-Fe2O3 and micro-Al＋micro-Fe2O3, respectively. Four thermites, namely, nano-Al/xero-Fe2O3, nano-Al＋micro-Fe2O3, micro-Al/xero-Fe2O3, and micro-Al＋micro-Fe2O3, were heated from ambient temperature to 1020 ℃, during which the products at 660 ℃ and 1020 ℃ were collected and analyzed by XRD. Crystals of Fe, FeAl2O4, Fe3O4,α-Fe2O3, Al,γ-Fe2O3, Al2.667O4, FeO andα-Al2O3 were indexed in XRD patterns. For each thermite, according to the specific products, the possible equations were given. Based on the principle of the minimum free energy, the most reasonable equations were inferred from the possible reactions.

Reaction mechanisms of low-grade molybdenum concentrate during calcification roasting process

The effects of Ca-based additives on roasting properties of low-grade molybdenum concentrate were studied. The resultsshow that calcium-based additives can react with molybdenum concentrate to form CaSO4 and CaMoO4. The initial oxidationtemperature of MoS2 is 450℃, while the formation of CaMoO4 and CaSO4 occurs above 500℃. The whole calcification reactionsare nearly completed between 600 and 650℃. However, raising the temperature further helps for the formation of CaMoO4 but isdisadvantageous to sulfur fixing rate and molybdenum retention rate. Calcification efficiency of Ca-based additives follows theorder： Ca（OH）2〉CaO〉CaCO3. With increasing the dosage of Ca（OH）2, the molybdenum retention rate and sulfur-fixing rate rise, butexcessive dosages would consume more acid during leaching process. The appropriate mass ratio of Ca（OH）2 to molybdenumconcentrate is 1：1. When roasted at 650 ℃ for 90 min, the molybdenum retention rate and the sulfur-fixing rate of low-grademolybdenum concentrate reach 100% and 92.92%, respectively, and the dissolution rate of molybdenum achieves 99.12% withcalcines being leached by sulphuric acid.

Reaction mechanism of preparation of titanium by electro-deoxidation in molten salt

The electro-deoxidation of TiO2 was investigated in molten CaCl2.Back electromotive force measurements,constant voltage electrolytic experiments,contrast experiments of different cathodes,and cyclic voltammograms were carried out for solving the puzzle of reduction mechanism.The results showed that the reduction process proceeded step by step.TiO2 was first reduced to Ti3O5 or Ti2O3,and then further reduced to Ti3O,Ti2O,TiO and Ti.In addition,direct electrochemical reduction of titanium dioxide was the primary cathodic reaction;meanwhile,some calciothermic reduction reactions also happened at the cathode.Cyclic voltammograms of solid titanium dioxide and molybdenum wire in molten salts with different compositions were also studied.

Secondary reaction mechanism of leaching process of calcium aluminate slag

SiO2 in calcium aluminate slag exists in the form of γ-2CaO·SiO2 which is more stable than β-2CaO·SiO2. However, it is decomposed by sodium carbonate solution during leaching process, leading to the secondary reaction. The extent of secondary reaction and reaction mechanism of calcium aluminate slag were studied using XRD. The results show that the decomposition rate of γ-2CaO·SiO2 increases with the increase in leaching time and sodium carbonate concentration. The main products of secondary reaction are the mixture of hydrogarnet and sodium hydrate alumina-silicate. SiO2 concentration rises firstly and then drops with the increase of leaching temperature. XRD results indicate that the stable product of secondary reaction at low temperature is hydrogarnet. But hydrogarnet is transformed into sodium hydrate alumina-silicate at high temperature.