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The incomplete understanding of electron correlation is still profound due to the lack of exact solutions of the Schrödinger equation of many electron systems. In this work, we present the correlation-induced changes in the calculated many-electron systems beyond the standard residual. To locate the minimum of the Rayleigh quotient, each iteration is to seek the lowest eigenpairs in a subspace spanned by the current wave function and its gradient of the Rayleigh-quotient as well as the upcoming higher-order residual. Consequently, as the upcoming errors can be introduced and circumvented with the search in the higher-order residual, a concomitant improved performance in terms of number of iterations, convergence rate, and total elapsed time is very significant. The correlation energy components obtained with the original residual are corrected with the higher-order residual application, satisfying the correlation virial theorem with much improved accuracy. The comparison with the original residual, the higher-order residual significantly improves the electron binding, favoring the localization of electrons' distribution, revealed with the increasing peak of the distribution and correlation function and the reduced interelectron distance and its angle. [ABSTRACT FROM AUTHOR]

Li‐rich antiperovskite (LiRAP) hydroxyhalides are emerging as attractive solid electrolyte (SEs) for all‐solid‐state Li metal batteries (ASSLMBs) due to their low melting point, low cost, and ease of scaling‐up. The incorporation of rotational polyanions can reduce the activation energy and thus improve the Li ion conductivity of SEs. Herein, we propose a ternary rotational polyanion coupling strategy to fasten the Li ion conduction in tetrafluoroborate (BF4−) ion doped LiRAP Li2OHCl. Assisted by first‐principles calculation, powder X‐ray diffraction, solid‐state magnetic resonance and electrochemical impedance spectra, it is confirmed that Li ion transport in BF4− ion doped Li2OHCl is strongly associated with the rotational coupling among OH−, BF4− and Li2−O−H octahedrons, which enhances the Li ion conductivity for more than 1.8 times with the activation energy lowering 0.03 eV. This work provides a new perspective to design high‐performance superionic conductors with multi‐polyanions. [ABSTRACT FROM AUTHOR]

The biochar was prepared by pyrolyzing corn straw at 773 K temperature under an oxygen-limited condition. Then, the gained biochar samples were further modified with MgCl2 solution through mixing method for 3 h at the speed of 120 rpm. The physicochemical properties of the modified biochar from corn straw were investigated by surface area analysis, elemental analysis, scanning electron microscope, X-ray diffraction and Fourier transform infrared spectroscopy spectra. The adsorption experiments of ammonia nitrogen in aqueous solution by modified biochar were carried out. The results showed that the modified biochar contains high surface area, rough surface and a lot of oxygen-containing functional groups. The adsorption process fits well with the pseudo-second-order kinetics equation and Langmuir isotherm equation. The adsorption mechanism of modified biochar to NH4 + ion in aqueous solution includes ion exchange and physical adsorption. The ion exchange is primary in the process of adsorption.

An efficient sequential mechanochemical activation and complexation leaching for enhanced recovery of valuable metals from spent lithium-ion batteries was explored. The cathode material of lithium cobalt oxide (LiCoO2) was firstly ground in a planetary ball mill, and then diluted into an ethylene diamine tetraacetic acid (EDTA) and hydrogen peroxide (H2O2) leaching solution. One hundred percent of cobalt (Co) and 98.2% of lithium (Li) could be leached from the activated LiCoO2 materials compared with the non-activated (the leaching efficiencies of 7.9% for Co and 4.1% for Li), indicating that the mechanochemical activation process could significantly improve the EDTA/H2O2 mixed liquor complexation leaching of valuable metals from spent LIBs. The involved kinetics and mechanism were explored by carrying out characterization and theoretical calculations. Results demonstrated that an exponential kinetic model could well describe the mechanochemical process, and the Avrami equation leaching model provided a satisfactory fitting relevant for the subsequent improved leaching process. The breakage of the layer structure, the Co–O-Co unit, and the LiCoO2 surface, along with a decrease in activation energy, resulted in the enhancement of the leaching efficiency following mechanochemical activation. Enhanced leaching of Co was owing to the reduction of Co(III) to Co(II) instantaneously forming Co(II)-EDTA chelates. The acidity of EDTA and H2O2 promoted upgrade dissolution of lithium after mechanochemical activation for LiCoO2. This efficient and benign recovery process is of great significance for recycling spent LIBs. [ABSTRACT FROM AUTHOR]

First-principles calculations show a self-isomerization process of the nearly planar superatom, in which the maximum energy difference between different extreme points is below 0.1 eV and a crossing between singlet and triplet states is also involved. Further UV-Vis spectra reveal a correlation between the spectra and structures caused by self-isomerization. [ABSTRACT FROM AUTHOR]

Cancer‐derived exosomes are involved in the development of cancer cachexia. Carnosol, which exhibited ameliorating effects on cancer cachexia of C26 tumour‐bearing mice in our previous study, alleviated atrophy of C2C12 myotubes induced by exosomes of C26 tumour cells in the present study. MiR‐183‐5p was found to be rich in C26 cells and C26 exosomes, and miR‐183‐5p mimic could directly induce atrophy of C2C12 myotubes. Carnosol at 5 to 20 μM could dose‐dependently ameliorate the myotube atrophy induced by miR‐183‐5p. Four and a half LIM domain protein 1 (FHL1) was shown to be the direct target of miR‐183‐5p. Increase in myostatin, p‐Smad3, MuRF‐1, Atrogin‐1, HIF‐1α and p‐STAT3 and decrease in mitochondrial respiration were also induced by miR‐183‐5p mimic in C2C12 myotubes. Carnosol could not affect the decrease in FHL‐1 and the activation of STAT3 pathway but could significantly alleviate the increase in myostatin, p‐Smad3, MuRF‐1, Atrogin‐1 and the decrease in mitochondrial respiration induced by miR‐183‐5p. The protective effects of carnosol on myotubes against atrophy of C2C12 myotubes induced by miR‐183‐5p, based on both its inhibiting effects on MuRF‐1 and Atrogin‐1‐mediated protein degradation and its ability of keeping the mitochondrial respiration, might contribute to its ameliorating effects on cancer cachexia. [ABSTRACT FROM AUTHOR]

Graphitic carbon nitride (g-CN), as an orderly structured polymer derivative, has been widely concerned for its photocatalytic ability due to its metal-free nature and unique properties. However, the photoelectrochemical (PEC) application of g-CN is still hindered by the difficulty of forming high-quality films with good uniformity and crystallinity. Herein, we studied the rapid thermal vapor condensation (RTVC) for growing g-CN films with improved PEC activity. The polycondensation and polymerization reactions of precursor melamine molecules under the optimized temperature 600 °C and calcination time 20 min resulted in better crystallinity of g-CN films. Remarkably, the growth of g-CN film based on the coalescence of unambiguous hexagonal nanosheets was observed, as corroborated by scanning electron microscopy and transmission electron microscopy. This novel RTVC method offers a fast and easy strategy for improving the crystallinity of g-CN films through controlling the thermal dynamics and kinetics of film growth from temperature and time. [ABSTRACT FROM AUTHOR]

The development of highly sensitive, low-power consuming, stable and recyclable gas sensing devices at room temperature has become an important solution for environmental safety detection. Utilizing a two-dimensional metalloporphyrin monolayer for gas sensing is appealing due to its large specific surface area and high surface activity. A two-dimensional manganese porphyrin monolayer (2DMnPr) is selected from 2D metalloporphyrins with 3d metal centers due to its semi-metallicity to explore its gas sensing properties. Using first-principles calculations, we systematically investigate the electronic structures and adsorption characteristics of gas molecules with toxicity and greenhouse effect on the surface of 2DMnPr, including H2S, CO, CO2, SO2, NO and NO2. The strength of the interaction and charge transfer between the 2DMnPr surface and the adsorbed molecules have a direct effect on the electronic properties and the sensing properties of the adsorbent surface. The sensing performance of the 2DMnPr adsorbent is evaluated via two observable parameters: work function and electrical conductivity. The work functions of 2DMnPr after the adsorption of CO, SO2, NO and NO2 gas molecules increase by different degrees depending on the charge transfer, and those of the H2S and CO2 cases decrease. In our simulation, adsorption of CO, SO2, NO and NO2 gas molecules affects the electronic properties of 2DMnPr markedly, and current–voltage characteristics within a low bias range uncover the superior sensitivity of the conductivity of the 2DMnPr monolayer to these molecules. Besides, the sensing performance is demonstrated to be stable under strain and at room temperature. The desorption time of a gas is positively related to its adsorption energy. The recovery time of CO is predicted to be short enough to realize sustainable detection at room temperature, and the SO2, NO and NO2 gases can also be desorbed at higher temperatures. These results demonstrate that 2DMnPr enables the sensitive detection of these gases and predict the potential application of 2DMnPr as an ultra-sensitive, low-power, stable and recyclable gas sensor at room temperature. [ABSTRACT FROM AUTHOR]

Distinctive from conventional electronic structure methods, we solve the Schrödinger wave equations of the helium atom and its isoelectronic ions by employing one-dimensional basis functions to separate components. We use full two-electron six-dimensional operators and wavefunctions represented with real-space grids where the refinement of the latter is carried out using a residual minimization method. In contrast to the standard single-electron approach, the current approach results in exact treatment of repulsion energy and, hence, more accurate electron correlation within five centihartrees or better included, with moderate computational cost. A simple numerical convergence between the error to accurate results and the grid-spacing size is found. The obtained two-electron Schrödinger wavefunction that contains vast and elaborating information for the radial correlation function and common one-dimensional functions shows the electron correlation effect on one-electron distributions. [ABSTRACT FROM AUTHOR]

Carbon nitride (CN) films have emerged as promising photoelectrodes in photoelectrochemical (PEC) water-splitting cells. However, due to their intrinsic poor charge transfer dynamics and the absence of a controllable film deposition method, their performance remains unsatisfactory. Here, we report an in situ textured CN film that is strengthened by a band-gap state modulation strategy with superior PEC performance. The optimized film possesses a 15-fold improvement in photocurrent density over pristine CN film, reaching up to 119.2 μA cm−2 at 1.23 V versus RHE without any hole scavengers. Through experimental characterizations and theoretical verifications, we found that the remarkable photocurrent density originates from the synergistic effect of long wavelength photon harvesting and efficient charge migration. The substantial enhancement of PEC activity highlights the importance of nanoengineering in terms of controlling the macroscopic film morphology and modulating the microscopic electronic structure for the precise design of multipurpose photoelectrodes. [ABSTRACT FROM AUTHOR]