H2O Particles Research Articles

Novel synthesis of FeF3·0.33H2O@hollow acetylene black nanosphere and its long-life electrochemical properties as a cathode for lithium-ion batteries

Iron (III) fluoride (FeF3), characterized by high voltage and high specific capacity and emerges as a promising candidate for the forthcoming generation of cathode materials in lithium-ion batteries. This study employs a novel methodology by introducing Fe3+ sources into hollow acetylene black particles through a vacuum impregnation method. This innovative approach results in the synthesis of a composite material comprising FeF3∙0.33H2O encapsulated within hollow acetylene black nanospheres, denoted as the FeF3∙0.33H2O @hollow acetylene black nanosphere composite material (FF@HCN). The composite exhibits a shell composed of highly graphitized carbon and a core containing FeF3∙0.33H2O particles in the range of 10–20 nm. The proportion of active materials is 75.56 %. The acetylene black has chain-like structure and high specific surface area, significantly enhances the material's conductivity, contributing 74.4 % to the pseudocapacitance at a scan rate of 1 mV s−1. The cavity graphite shell plays a crucial role in restricting the expansion and pulverization decay of FeF3∙0.33H2O nanoparticles, thereby markedly improving the cycle stability. The initial capacity of the FF@HCN composite is 224.4 mAh g−1, and after 1000 cycles at 0.1 C, it maintains a capacity of 162.3 mAh g−1, resulting in a capacity retention rate of 72.3 % and decay per cycle of 0.027 %.

Nucleation of ice particles below the snow line

An increase in the total surface area of icy dust aggregates was numerically investigated. The temperature of icy dust aggregates in a protoplanetary disk changes through their vertical motion induced by turbulence. The ice becomes vapor if the maximum temperature exceeds the condensation temperature. The vapor molecules recondense when cooling proceeds. Depending on the cooling rate and the amount of the remaining aggregate, the vapor molecules form pure ice particles through homogeneous nucleation or recondense onto the remaining icy aggregates through heterogeneous nucleation. If homogeneous nucleation dominates, the total surface area substantially increases from the original value. The increase in the total surface area was determined for various ice species and vertical temperature distributions. H2O, NH3, and H2S ice particles can be formed through homogeneous nucleation. The total surface area is increased by a factor of up to 400. The increase in the total surface area can affect protoplanetary disk’s surface density and temperature distributions.

Hydrothermal synthesis of dittmarite-group NH4(Co1-xMnx)PO4·H2O particles as inorganic violet pigments.

Dittmarite-group NH4(Co1-xMnx)PO4·H2O particles were prepared via a hydrothermal route. Single-phase platelike NH4(Co1-xMnx)PO4·H2O particles were obtained from aqueous solutions containing MnCl2·4H2O, CoCl2·6H2O, and (NH4)2HPO4, where the [Mn2+]/([Co2+] + [Mn2+]) mole ratios in the products were controlled by changing the MnCl2 and CoCl2 concentrations of the precursor solutions. The vivid violet colour of the ammonium cobalt phosphate (NH4CoPO4·H2O) particles was maintained upon substitution of Co2+ with Mn2+ ions up to x = 0.8, thus achieving an 80% saving of cobalt in the preparation of violet pigments.

A Pathway for Collisional Planetesimal Growth in the Ice-dominant Regions of Protoplanetary Disks

We present a semi-analytic model for the growth, drift, desorption, and fragmentation of millimeter- to meter-sized particles in protoplanetary disks. Fragmentation occurs where particle collision velocities exceed critical fragmentation velocities. Using this criterion, we produce fragmentation regions in disk orbital radius–particle size phase space for particles with a range of material properties, structures, and compositions (including SiO2, Mg2SiO4, H2O, CO2, and CO). For reasonable disk conditions, compact aggregate H2O, CO2, and CO ice particles do not reach destructive relative velocities and are thus not likely to undergo collisional fragmentation. Uncoated silicate particles are more susceptible to collisional destruction and are expected to fragment in the inner disk, consistent with previous work. We then calculate the growth, drift, and sublimation of small particles, initially located in the outer disk. We find that ice-coated particles can avoid fragmentation as they grow and drift inward under a substantial range of disk conditions, as long as the particles are aggregates composed of 0.1 μm-sized monomers. Such particles may undergo runaway growth in disk regions abundant in H2O or CO2 ice, depending on the assumed disk temperature structure. These results indicate that icy collisional growth to planetesimally relevant sizes may happen efficiently throughout a disk’s lifetime, and is particularly robust at early times when the disk’s dust-to-gas ratio is comparable to that of the interstellar medium.

Molecular dynamics investigation on structural and interfacial characteristics of aerosol particles containing mixed organic components

Microscopic morphology plays a significant role in the description of aerosol particle evolution, but the knowledge on particles containing mixed organic matters is insufficient. In this study, molecular simulation (MD) method is employed to investigate the morphologies of particles containing two or three of malonic acid (MA), adipic acid (AA) and eicosane (C20). The key point is the effects of organic species and water content on structural and interfacial characteristics of particles. Results show that all dry particles exhibit the approximate core-shell structure with the shell composed of organic with longer hydrocarbon chain. With water content increasing from 100 to 1000, MA + AA + H2O particles present the core-shell structure with decreasing MA in the core, while particles containing C20 successively exhibit the core-shell structure and the ball-cap structure with three layers. These structural differences are caused by the surface propensity of organics, which is positively correlated with both the length of hydrocarbon chain and the water content. At the particle surface, hydrophobic groups of organic molecules direct towards the gas phase. MA (AA) located between water droplet and C20 cluster orient their hydrophobic groups toward C20. Furthermore, ratios of hydrophilic and hydrophobic atoms (K) at the surface of all studied particles increases with increasing water content, and at each water content the order is K(MA + AA) > K(MA + AA + C20) > K(AA + C20) > K(MA + C20). These findings provide microscopic information support for the development of theoretical model for the particle formation and growth.

Enhancing electrochemical lithium-storage properties of hydrated iron oxalate (FeC2O4·2H2O) anode material by combining with dual-states copper

The application of iron oxalate (FeC2O4) as a new high-energy anode material for lithium-ion batteries is astricted by difficulty in obtaining 100 % anhydrous material and inhibitive role of crystal water on lithium storage. Herein, we fabricated the trepang-liked hydrated iron oxalate (FeC2O4·2 H2O) anode materials by combining with dual-states copper and investigated the special function of copper. Because of the differentiated distribution between C2O42- and oxalic acid complexes ([Fe(C2O4)x]-2(x-1) and [Cu(C2O4)x]-2(x-1)), the CuC2O4·xH2O nanosheets with compound state adsorb and imbed on surface of rod-like FeC2O4·2 H2O particles. Meanwhile, copper element with ion state can effectively doped into the crystal structure of FeC2O4·2 H2O, due to the similar three-dimensional crystal structure between transition metal oxalates. In virtue of the differentiated electrochemical behavior of crystal water for iron oxalate and copper oxalate, the copper derivatives (Cu, CuO, Cu2O et al.), formed by the reaction between CuC2O4·xH2O and Li+, exhibit high electrochemical activity and electrical conductivity, which can significantly enhance the lithium storage ability of dihydrate iron oxalate. Hence, hydrated iron oxalate combined with dual-states copper, suggests superior reversible capacity (∼550 mAh g-1 at 0.1 A g-1) and stable long-term cycling performance (∼520 mAh g-1 at 0.5 A g-1 after 200 cycles). This paper provides a novel opportunity to weaken the inhibitive role of crystal water on lithium storage and enhance the electrochemical properties of hydrous oxalate materials.

Cellulose filter papers derived separator featuring effective ion transferring channels for sodium-ion batteries

As a basic component of batteries, separators are proposed to apart the two electrodes while allowing the transport of ionic charge carriers. Cellulose separators have attracted tremendous attention due to their excellent thermal stability and wettability. In this study, we prepare all-cellulose composite (ACC) separators coated with Zn5(OH)8Cl2·H2O (ZHC) particles. The surface of the cellulose filter paper is partially dissolved by the 65% ZnCl2 solution, forming a tortuous and porous all-cellulose composite membrane. At the same time, ZHC is generated in situ on the surface during the removal of residual ZnCl2 from the cellulose, which effectively promotes the passage of a sodium ion (Na+) and substantially improves the cycling performance of the batteries. Density functional theory (DFT) calculations demonstrate that suitable adsorption energy on ZHC is favorable for promoting Na+ transport. The corresponding ACC separator exhibits high ionic conductivity (2.75 mS/cm) and Na+ transference number (0.82), correspondingly the assembled Na/hard carbon half-cells show an excellent reversible specific capacity (315 mA h/g at 25 mA/g) and cycling stability (the retention is 97.77% after 50 cycles at 50 mA/g), outperforming the glass fiber separator in both sodium-ion half-cell and full-cell.

Novel Enrofloxacin Schiff Base Metal Complexes: Synthesis, Spectroscopic Characterization, Computational Simulation and Antimicrobial Investigation against Some Food and Phyto-Pathogens

Condensation of the reaction between enrofloxacin and ethylenediamine in the existence of glacial acetic acid produced a new N,N-ethylene (bis 1-cyclopropyl-7-(4-ethylpiperazin-1-yl)-6-fluoro-1,4-dihydroquinoline-3-carboxylic acid Schiff base (H2Erx-en). H2Erx-en was used as a tetra-dentate ligand to produce novel complexes by interacting with metal ions iron(III), yttrium(III), zirconium(IV), and lanthanum(III). The synthetic H2Erx-en and its chelates had been detected with elemental analysis, spectroscopic methods, mass spectrometry, thermal studies, conductometric and magnetic measurements experiments. The calculated molar conductance of the complexes in 1 × 10−3 M DMF solution shows that iron(III), yttrium(III) and lanthanum(III) are 1:1 electrolytes, however the zirconium(IV) complex is non-electrolyte. The infrared spectra of H2Erx-en chelates indicated that the carboxylic group is deprotonated and H2Erx-en is associated with metals as a tetra-dentate through nitrogen and oxygen atoms. The disappearance of the carboxylic proton in all complexes corroborated information concerning H2Erx-en deprotonation and complexation with metal ions, according to 1H NMR data. Thermal analysis revealed the abundance of H2O particles in the chelates’ entrance and outlet spheres, indicating the disintegration pattern of H2Erx-en and their chelates. The Coats–Redfern and Horowitz–Metzeger approaches were utilized to calculate the thermodynamic items (Ea, ΔS *, ΔH *, and ΔG *) at n = 1 and n ≠ 1. The resulting data reveal better organized chelate building activation. Density functional theory (DFT) was created to properly grasp the optimal architecture of the molecules. The chelates are softer than H2Erx-en, with estimates varying between 95.23 eV to 400.00 eV, compared to 31.47 eV for H2Erx-en. The disc diffusion technique was utilized to assess H2Erx-en and their chelates in an antimicrobial assay against various food and phytopathogens. The zirconium(IV) chelate has the most potent antibacterial action and is particularly efficient against Salmonella typhi.

Microscopic insight into catalytic HCN removal over the CuO surface in chemical looping combustion

Hydrogen cyanide (HCN) is well-accepted as a main nitrogen-containing precursor from fuel nitrogen to nitrogen oxides. When using coal as fuel with a CuO-based oxygen carrier in chemical looping combustion (CLC), complex heterogeneous reactions exist among the system of HCN, O2, NO, H2O, and CuO particles. This work performs density functional theory (DFT) calculations to systematically probe the microscopic HCN heterogeneous reactions over the CuO particle surface. The results indicate that HCN is chemisorbed on the CuO surface, and the third dissociation step within the consecutive three-step HCN dissociations (HCN*→CN*→NCO*→N*) is the rate-determining step. Namely, the CN*/NCO* radicals can be deemed as an indicator of the performance of HCN removal due to their quite higher dissociation energies. With the existence of O2, H2O, and NO, the reaction mechanism of HCN conversion becomes extremely complex. Both DFT calculations and kinetic analyses determine that O2, NO, and H2O all significantly accelerate the consumption of CN*/NCO* radicals to produce various N-containing species (NOx or NH3) to different extents. Finally, a skeletal reaction network in a system of O2/NO/H2O/HCN is concluded, which clearly elucidates that CuO exhibits excellent catalytic activity toward HCN removal.

In-situ dual-deoxidation design of advanced titanium matrix composites by pressureless sintering

We establish a methodology of in-situ dual-deoxidation to fabricate advanced titanium matrix composites (TMCs) by pressureless sintering (PLS). Specifically, the in-situ dual-deoxidation of impurity O in Ti matrix was designed as the in-situ formation of H2O and La2O3 particles, which was accomplished by PLS of advanced TMCs from powder mixtures containing Ti–6Al–4V matrix of TiH2 and 60Al40V together with LaB6 addition. Interestingly, the advanced TMCs with in-situ La2O3 particle and TiB whisker have various merits, including the significantly reduced O content in the Ti matrix, the refined equiaxed α-Ti grain with monolayer nanosized L phase grain boundary, and especially the nearly full-density evading Kirkendall's pore. Resultantly, the advanced TMCs circumvent the strength–ductility trade-off of representative Ti–6Al–4V TMCs by various materials processing methods. Our results provide a novel strategy for fabricating cost-effective advanced TMCs by PLS to yield superior mechanical properties.

Viscosity and physical state of sucrose mixed with ammonium sulfate droplets

Abstract. Although knowledge of the physical state of aerosol particles is essential to understand atmospheric chemistry model and measurements, information on the viscosity and physical state of aerosol particles consisting of organic and inorganic salts is still rare. Herein, we quantified viscosities at 293 ± 1 K upon dehydration for the binary systems, sucrose–H2O and ammonium sulfate (AS)–H2O, and the ternary systems, sucrose–AS–H2O for organic-to-inorganic dry mass ratios (OIRs) = 4:1, 1:1, and 1:4 using bead-mobility and poke-and-flow techniques. Based on the viscosity value of the aerosol particles, we defined the physical states of the total aerosol particles studied in this work. For binary systems, the viscosity of sucrose–H2O particles gradually increased from ∼ 4 × 10−1 to > ∼ 1 × 108 Pa s when the relative humidity (RH) decreased from ∼ 81 % to ∼ 24 %, ranging from liquid to semisolid or solid state, which agrees with previous studies. The viscosity of AS–H2O particles remained in the liquid state (< 102 Pa s) for RH > ∼ 50 %, while for RH ≤∼ 50 %, the particles showed a viscosity of > ∼ 1 × 1012 Pa s, corresponding to a solid state. In case of the ternary systems, the viscosity of organic-rich particles (OIR = 4:1) gradually increased from ∼ 1 × 10−1 to ∼ 1 × 108 Pa s for a RH decrease from ∼ 81 % to ∼ 18 %, similar to the binary sucrose–H2O particles. This indicates that the sucrose–AS–H2O particles range from liquid to semisolid or solid across the RH. In the ternary particles for OIR = 1:1, the viscosities ranged from less than ∼ 1 × 102 for RH > 34 % to > ∼ 1 × 108 Pa s at ∼ 27 % RH. The viscosities correspond to liquid for RH > ∼ 34 %, semisolid for ∼ 34 % < RH < ∼ 27 %, and semisolid or solid for RH < ∼ 27 %. Compared to the organic-rich particles, in the inorganic-rich particles (OIR = 1:4), drastic enhancement in viscosity was observed as RH decreased; the viscosity increased by approximately 8 orders of magnitude during a decrease in RH from 43 % to 25 %, resulting in liquid to semisolid or solid in the RH range. Overall, all particles studied in this work were observed to exist as a liquid, semisolid, or solid depending on the RH. Furthermore, we compared the measured viscosities of ternary systems with OIRs of 4:1, 1:1, and 1:4 to the predicted viscosities using the Aerosol Inorganic–Organic Mixtures Functional groups Activity Coefficients Viscosity model (AIOMFAC-VISC) predictions with the Zdanovskii–Stokes–Robinson (ZSR) organic–inorganic mixing model, with excellent model–measurement agreement for all OIRs.

Surfactant-Free Facile Synthesis of Nickel Oxalate Monodispersed Particles in Novel Morphologies

The surfactant or shape modifier used in the synthesis of monodispersed uniform fine particles affected the performance of the prepared powder in its applications. The present investigation is related to synthesizing colloidal uniform fine particles of nickel oxalate in novel morphologies under an optimized set of reaction conditions without using any surfactant or shape modifier. SEM results revealed that the reactant concentration significantly affected the characteristics of the precipitated solids, which ranged from gel to dispersion of discrete particles. Particles of uniform morphological features were obtained under an optimized set of experimental conditions, i.e., reactant concentration, temperature, aging time, etc. The molar ratio of the precursors affected the particle’s growth mechanism as the spherical morphology of the particles changed to a cubic shape by increasing nickel ion concentration in the recipe at 25 oC. The cubic morphology transformed into toffee shape bigger particles of a 0.5 axial ratio by increasing the reaction mediumand#39;s thermal energy. The synthesized particles were characterized by various physical techniques, which confirmed the product as the monodispersed pure NiC2O4.2H2O particles.

Understanding electrochemical and structural properties of copper hexacyanoferrate: Application in hydrogen peroxide analysis

Copper hexacyanoferrate (CuHCF) exhibits great electrocatalytic activity towards H2O2 reduction, making it a suitable electrode material for H2O2 sensors and H2O2-based energy storage devices. In this work, the crystal structures, electronic structures, and electrochemical properties of CuHCF were investigated in detail by both experiments and simulation. Several different samples of CuHCF were synthesized and tested. The effects of Fe oxidation states and the Cu-to-Fe ratios on the electroactivities of CuHCF were evaluated. In-depth voltammetric and X-ray absorption near edge structure (XANES) studies revealed the underlying redox chemistry which contribute to the voltammetric responses of CuHCF. High electroactivity of CuHCF, high cycling stability, and high electrocatalytic activity towards H2O2 reduction were observed for the porous K0.09Cu[Fe(CN)6]0.6 •2.56 H2O particles synthesized at room temperature from chemical co-precipitation of CuSO4 and K3Fe(CN)6 at a 2:1 molar ratio. DFT calculation revealed favorable adsorption of H2O2 on Fe sites. The presence of Cu lowered the local charge on Fe, assisting the adsorption of electron-donating H2O2 molecule on the neighboring Fe atom. The excellent analytical performance of CuHCF towards H2O2 detection was further demonstrated, giving the linear range of 0.0 – 10.0 mM, the sensitivity of 10.6 µA mM‒1, and the limit of detection (3sB/m) of 0.033 mM.

Viscosity and phase state of aerosol particles consisting of sucrose mixed with inorganic salts

Abstract. Research on the viscosity and phase state of aerosol particles is essential because of their significant influence on the particle growth rate, equilibration times, and related evolution of mass concentration as well as heterogeneous reactions. So far, most studies of viscosity and phase state have been focused on organic aerosol particles, yet data on how viscosity can vary when the organic materials are mixed with inorganic salts remain scarce. Herein, using bead-mobility and poke-and-flow techniques, we quantified viscosities at 293 ± 1 K for binary mixtures of organic material / H2O and inorganic salts / H2O, as well as ternary mixtures of organic material / inorganic salts / H2O over the atmospheric relative humidity (RH) range. Sucrose as the organic species and calcium nitrate (Ca(NO3)2) or magnesium nitrate (Mg(NO3)2) as the inorganic salts were examined. For binary sucrose / H2O particles, the viscosities gradually increased from ∼ 3 × 10−2 to ≳1 × 108 Pa s as RH decreased from ∼ 75 % to ∼ 25 %. Compared with the results for the sucrose / H2O particles, binary Ca(NO3)2/H2O and Mg(NO3)2/H2O particles showed drastic enhancements to ≳1 × 108 Pa s at low RH close to the efflorescence RH. For ternary mixtures of sucrose / Ca(NO3)2 / H2O or sucrose / Mg(NO3)2 / H2O, with organic-to-inorganic mass ratios of 1:1, the viscosities of the particles gradually increased from ∼ 3 × 10−2 to greater than ∼ 1 × 108 Pa s for RH values from ∼ 75 % to ∼ 5 %. Compared to the viscosities of the Ca(NO3)2/H2O particles, higher viscosities were observed for the ternary sucrose / Ca(NO3)2 / H2O particles, with values increased by about 1 order of magnitude at 50 % RH and about 6 orders of magnitude at 35 % RH. Moreover, we applied a thermodynamics-based group-contribution model (AIOMFAC-VISC, Aerosol Inorganic–Organic Mixtures Functional groups Activity Coefficients Viscosity) to predict aerosol viscosities for the studied systems. The model predictions and viscosity measurements show good agreement within ∼ 1 order of magnitude in viscosity. The viscosity measurements indicate that the studied mixed organic–inorganic particles range in phase state from liquid to semi-solid or even solid across the atmospheric RH range at a temperature of 293 K. These results support our understanding that organic / inorganic / H2O particles can exist in a liquid, semisolid, or even a solid state in the troposphere.

Comparative Analysis of 3D Graphene–LiOH·H2O Composites by Modification with Phytic Acid and Ascorbic Acid for Low‐Grade Thermal Energy Storages

3D Graphene (3D‐GF) modified with different additive concentrations (phytic acid [PA] and ascorbic acid [AA]) is developed and then combined with different LiOH contents by the hydrothermal method to obtain composite materials. It can be found that the addition of PA and AA will not destroy the carbon skeleton structure of 3D‐GF. With increasing additive content, the thermal conductivities of modified 3D‐GF first increase and reach their maximum values at 8 mg mL−1. The modified 3D‐GF with the highest thermal conductivity is selected to be combined with different LiOH contents. The addition of PA and AA can broaden the charging temperature range from 60–110 to 30–200 °C and improve the LiOH hydration rate and heat storage density. Compared with the PA‐modified composite, the AA‐modified composite shows smaller (about 7.6 nm) and more uniform LiOH·H2O particles (the particles size standard deviation of 3D‐GF‐AA‐LiOH·H2O is 1.1503), a larger specific surface area (119 m2 g−1), higher heat storage density (the highest value of 2763 kJ kg−1 for LiOH⋅H2O, which can be about 4.2 times of pure LiOH), and less influenced by the change of LiOH content (the thermal conductivity standard deviation of 3D‐GF‐AA‐LiOH·H2O is 0.123).

Self-assembly synthesis of dumbbell-like MnPO4·H2O hierarchical particle and its application in LiMnPO4/C cathode materials

The large-scale and efficient synthesis of MnPO4·H2O is an urgent problem to be solved. In this paper, self-assembled dumbbell-shaped MnPO4·H2O particles were successfully synthesized just using KMnO4 and commercial concentrated H3PO4, and then employed as the precursor to prepare LiMnPO4/C composites. The XRD, SEM, TEM, and electrochemical performance tests were used to investigate MnPO4·H2O and the corresponding LiMnPO4/C. The formation mechanism of MnPO4·H2O was discussed. The results showed that temperature and water content have a significant effect on the yield, purity, and morphology of MnPO4·H2O. The synthesized LiMnPO4/C with reduced carbon content at 650 °C delivered a discharge capacity of 109.3 mA h g-1 at 1 C and 104.3 mA h g-1 at 2 C. This green and efficient synthesis method of MnPO4·H2O provides a new idea for the large-scale preparation of LiMnPO4/C cathode materials.

Wet milling synthesis of NH4CoPO4·H2O platelets: Formation reaction, growth mechanism, and conversion into high-voltage LiCoPO4 cathode for Li-ion batteries

A ball milling process not only affords particle size reduction by grinding but also particle synthesis induced by mechanical actions at ambient temperature. However, in traditional mechanical synthesis, it is difficult to control the particle morphology, including the size and shape, because of collision with the balls. This study shows that platelet-like NH4CoPO4·H2O particles are synthesized via wet planetary ball milling and converted into a high-voltage LiCoPO4 cathode for Li-ion battery. The NH4CoPO4·H2O platelets formed by the dissolution–precipitation reaction are repeatedly ground, dissolved into a solution, and recrystallized to afford crystal growth during the milling treatment. The converted LiCoPO4 cathodes retain the precursor morphologies, exhibiting high discharge capacities for flake particles and better cyclabilities for large platelet particles. The mechanical-assisted particle synthesis in solution is a simple method for the large-scale production of morphology-controlled nanomaterials.

Recovery of vacuum condition and plasma performance after vessel vent in EAST tokamak

The plasma recovery after vessel vent is studied in the EAST 2019 spring campaign. The removal of condensate water is important for the fully superconducting tokamak. The low-Z impurities are mostly removed after a baking cycle for 200 h and GDC for 111 h. About 49% of H2 and 40% of H2O molecules are removed in this phase. The clean ultra-high vacuum pressure is re-obtained to 3.0 × 10−6 Pa. In a follow-up process, about ~550 shots with an accumulated plasma duration of 4100 s are carried out to further remove implanted impurities. In the initial discharge stage, the removal rates of H2 and H2O particles are 4.7 × 1021 molecules/(m2·h) and 3.1 × 1021 molecules/(m2·h), respectively, which are ~4 times higher than that during D2/He-GDC and baking. About 31% of H2 and H2O impurities are removed due to the effect of initial plasma shots. And the repeatable plasma shots are achieved with the decrease of impurity level. The results provide reference for the arrangement of recovery plan after vacuum failure of EAST, ITER, CFETR and superconducting fusion devices.

Electrochemical and Theoretical Study of Corrosion Inhibition on Carbon Steel in 1M HCl Medium by 1,10-Bis(4-Amino-3-Methyl-1,2,4-Triazole-5-Thioyl)Decane

Corrosion inhibition using bolaamphiphile surfactants is related to the ability of these compounds to adsorb on liquid–solid interface. In this work, we have synthesized the 1,10-bis(4-amino-3-methyl-1,2,4-triazole-5-thioyl)decane (DTC10) using a new method developed in our laboratory. The synthesized compounds have been purified and characterized by NMR1H and NMR13C spectroscopy. The inhibiting action of DTC10 toward the corrosion of carbon steel in HCl1M solution was investigated using potentiodynamic and electrochemical impedance spectroscopy. We have shown that this compound acts as very good inhibitor for carbon steel in 1M HCl. The values of the transfer resistance, obtained from impedance plots of carbon steel, increase by increasing inhibitor concentration and reach 92% for 10−3M of DTC10. The effects of temperature and immersion time on the inhibition efficiency have also been studied. The effect of temperature was studied between 298 and 328 K; the activation energy Ea and other thermodynamic parameters were calculated. Donating and anti-donating properties of the studied inhibitor 1,10-bis(4-amino-3-methyl-1,2,4-triazole-5-thioyl)decane (DTC10) were illustrated using nucleophilic P− and electrophilic P+ Parr functions based on the density functional theory (DFT). The computational Monte Carlo (MC) method was performed to study the adsorption behavior of DTC10 onto Fe(111) surface in the solution (presence of H3O+, Cl− and H2O particles) and in the vacuum (absence of H3O+, Cl− and H2O particles). Accordingly, the adsorption of DTC10 on the iron surface (111) is more preferred in the solution than in the vacuum.

Highly Crystalline Ni-Co Layered Double Hydroxide Fabricated via Topochemical Transformation with a High Adsorption Capacity for Nitrate Ions.

Layered double hydroxide (LDH) has emerged as promising candidates for removing harmful oxoanions (i.e., SO42-, HPO42-, andNO3- ions) from wastewater because of their intrinsic ability to accommodate anionic species in the interlayer space. Highly crystalline [Ni0.67Co0.33(OH)2]Cl0.29·0.53H2O (Ni-Co LDH) particleswith an exceptionally high anion-exchange capacity of 58.8 mg g-1 and a distribution coefficient (Kd) of 2396 mL g-1 for NO3- ions were successfully prepared by the flux method and a topochemical strategy. Layered Na0.97Ni0.67Co0.33O2 (NNCO) was prepared using a high-temperature flux and used as a starting material for topotactic transformation consisting of oxidative hydrolysis with KOH and NaClO and subsequent reduction with H2O2 and NaCl. During the transformation from NNCO to Ni-Co LDH, a drastic change in the valences of the Ni and Co belonging to the host layer and in the cationic and anionic species occurs in interlayer space; the valences of the Ni and Co in NNCOwereincreased from Ni2+,3+ and Co2+,3+ to Ni3+ and Co2+,3+,4+ by an oxidative hydrolysis reaction with simultaneous intercalation of K+ionsand deintercalation of Na+ions,and subsequentlydecreased from Ni3+ and Co2+,3+,4+ to Ni2+ and Co2+,3+ by a reduction reaction with simultaneous intercalation of anionic species such as CO32- and Cl-ionsand deintercalation of Na+ and K+ions. Through synchrotron powder X-ray diffraction analysis and Rietveld refinement, the resultant Ni-Co LDH was clearly shown to exhibit high crystallinity with less compositional deviation even after topochemical transformation in comparison with the one prepared by traditional coprecipitation and solid-state methods. Furthermore, the adsorption isotherm for NO3- ions elucidated that homogeneous adsorption sites are consistently constructed in the crystal structure, which could be found from the fitting to a Langmuir curve, with the R2 value being 0.98. This work opens up a new route for the fabrication of excellent not only ion-exchangeable but also ion-conductive inorganic materials for direct utilization in environmental and energy-storage processes.