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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]

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]

To explore the threshold of ALT for initiating antiviral therapy in HBV infected patients, and to provide a basis for initiating antiviral therapy in chronic HBV-infected patients. Methods This retrospective cohort study recruited 707 consecutive treatment-naïve chronic hepatitis B (CHB) patients undergoing diagnostic liver biopsy in the department of infectious diseases of the Affiliated Hospital of Yan'an University from October 2013 to August 2018. Liver biopsy specimens were obtained under ultrasound guidance using Menghini 16G disposable needles. The METAVIR scoring system, which is commonly used internationally, was used to divide the patients into the group with mild liver tissue injury and the group with significant liver tissue injury, and the alanine aminotransferase (ALT) levels were measured separately. Receiver operating characteristic (ROC) curve and Mann-Whitney U test were used to evaluate the diagnostic value of ALT for significant liver tissue injury under different demographic characteristics. Results Of 707 patients, 292 (41.30%) had significant liver tissue injury confirmed by liver biopsy (METAVIR ≥A2 and/or F2). When the ULN of ALT was set to NICE criteria (30 U/L for males, 19 U/L for females), AASLD criteria (35 U/L for males, 25 U/L for females) and EASL or APASL criteria (40 U/L for males and females), CHB patients with 30 years olds, 22 U/L for HBeAg negative and 31 U/L for HBeAg positive patients. Conclusions The threshold of ALT for initiating antiviral therapy in chronic HBV patients should be individualized, especially should be down-regulated for the females, olders and HBeAg-negative patients. [ABSTRACT FROM AUTHOR]

The minimization of the commutator of the Fock and density matrices as the error matrix in the direct inversion of the iterative subspace (CDIIS) developed by Pulay is a powerful self‐consistent field (SCF) acceleration technique for the construction of optimum Fock matrix, if initiated with a fair initial guess. In this work, we present an alternative minimized error matrix to the commutator in the CDIIS, namely the residual or the gradient of the energy‐functional for a Slater determinant subject to the orthonormality constraints among orbitals, representing the search for a newly improved Fock matrix in the direction of the residual in the direct inversion of the iterative subspace (RDIIS). Implemented in the computational chemistry package GAMESS, the RDIIS is compared with the standard CDIIS and the second order SCF orbital optimization (SOSCF) for tested molecules started with a crude guess. As a result, the RDIIS stably and efficiently performs the SCF convergence acceleration. Furthermore, the RDIIS is considerably independent on the subspace size with the concentrated linear coefficients accounting proportionally for the Fock matrices close to the current iteration. [ABSTRACT FROM AUTHOR]

To clarify the pollution characteristics and sources of atmospheric VOCs in Zhengzhou City in the summer, multi-site offline sampling and laboratory analyses of atmospheric VOCs in Zhengzhou were carried out in August 2022. The observed and initial VOC volume fraction levels, OFP, SOAFP, and sources were compared. During the study period, the average values of three-site observation and initial φ （VOCs） during the study period were （31.83 ±13.51）×10 -9 and （35.92 ±15.30）×10 -9 ,respectively. Olefins （52.5 %） and aromatic hydrocarbons （29.7 %） were the components with a higher photochemical loss rate, and the spatial variations of the observed TVOCs concentration at each site were： Zhengzhou University （ZZU） > Gangli Reservoir （GLR） > Jingkaiqu （JKQ）, and the concentrations of alkanes and OVOCs at each site were higher. Olefins and aromatic hydrocarbons were the components that contributed greatly to the formation of O 3 and SOA. Motor vehicle sources, solvent-use sources, and industrial sources were the main contributing sources of atmospheric VOCs in Zhengzhou. Compared with the source analysis results based on the initial concentration, the contribution rates of motor vehicle sources, industrial sources, and solvent use sources were relatively high, and the contribution rates of combustion sources, plant sources, and oil and gas volatilization sources were relatively low.

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 (BF 4 - ) ion doped LiRAP Li 2 OHCl. 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 BF 4 - ion doped Li 2 OHCl is strongly associated with the rotational coupling among OH - , BF 4 - and Li 2 -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., (© 2024 Wiley-VCH GmbH.)

Organic acids in atmospheric particulate matter are widely involved in various physical and chemical reactions in the atmosphere and contribute greatly to the formation of secondary organic aerosols and haze pollutions. Therefore， the concentration distribution characteristics， sources， and secondary formation of organic acids in particulate matter are of great significance for further investigation of organic aerosols and their secondary transformation. Fine particulate matter （PM 2.5 ） samples were collected in Zhengzhou， and three types of organic acids， including dicarboxylic acids， fatty acids， and resin acids， were analyzed to explore their species distribution， seasonal variations， source contribution， and secondary generation. Malonic acid （di-C 3 ） and succinate acid （di-C 4 ） were the most abundant in the identified dicarboxylic acids， which showed obvious seasonal variations in the order of summer > autumn > winter > spring. Fatty acids had the highest concentration in winter and the lowest concentration in spring， showing obvious bimodal advantages， with the most abundant compounds being palmitic acid and stearic acid （C 18 ）. Principal component analysis and multiple linear regression （MLR） were used to analyze the source of organic acids in PM 2.5 in Zhengzhou； the results showed that 35% of the organic acids came from combustion and traffic sources， 24% from cooking sources， 23% from secondary formation， and 17% from natural sources. The ratios of the selected marker species （i.e.， di-C 3 / di-C 4 ， F/M， and C 18：1 / C 18 ） were used as tracers for the secondary formation of the organic aerosol and its aging process. The results showed that the photochemical reaction was intense in summer， and the proportion of organic aerosol aging or secondary production was high， whereas the photochemical reaction was weak in winter， and the aging degree of organic aerosol was low. Correlation analysis and MLR were used in combination to quantify the relative contribution of gas-phase oxidation and liquid-phase oxidation to dicarboxylic acid formation， and the results showed that gas-phase oxidation played a dominant role in the sampling period （accounting for 58%）， especially in summer （61%）.

In order to study the pollution characteristics of volatile organic compounds （VOCs）， continuous monitoring of VOCs in two pollution processes was conducted in June and December 2021 in Zhengzhou. Combined with meteorological conditions， the pollution characteristics， source contributions， and reactivity of VOCs in winter and summer were compared and analyzed. The results showed that the volume fraction of atmospheric VOCs in two episodes were （27.92±12.68）×10 -9 and （24.30±5.93）×10 -9 ， respectively. The volume fraction of atmospheric VOCs in the haze pollution process in winter was larger than that in the ozone pollution process in summer. The analysis results of winter sources were as follows： industrial source （27.0%）， motor vehicle source （22.5%）， combustion source （20.1%）， solvent use source （16.3%）， and oil and gas volatilization source （14.1%）. The analysis results of summer sources were as follows： motor vehicle source （24.8%）， industrial source （24.1%）， solvent source （17.4%）， oil and gas volatilization source （14.2%）， combustion source （11.2%）， and plant source （8.4%）. The results of the smog production model showed that the proportion of days in the synergistic control zone of VOCs during the two pollution processes in summer （66.7%） was smaller than that in winter （100.0%）. The secondary reaction activity results showed that the average ·OH loss rate （ L ·OH ） values in winter and summer were 4.12 s -1 and 4.75 s -1 ， respectively. The average ozone formation potential （OFP） values in summer were 108.36 μg·m -3 . The olefins were dominant in the top ten species due to L ·OH and OFP contributions in summer. The total SOAFP values in winter in Zhengzhou were 54.38 μg·m -3 . Among the top ten species contributing to SOAFP in winter， nine were aromatic hydrocarbons.

Nitrate (NO 3 - ), sulfate (SO 4 2- ), and ammonium (NH 4 + ) are important components of PM 2.5 , and studying their characteristics and influencing factors is essential for the continuous improvement of air quality. A series of online instruments were used to analyze the chemical components of PM 2.5 in Zhengzhou in the summer of 2020. The results showed that the average ρ (PM 2.5 ) was (28 ±13) μg·m -3 , showing a daily variation characteristic of high at night and low during the day. The main concentrations of NO 3 - , SO 4 2- , and NH 4 + were (7.8 ±6.7), (7.2 ±3.7), and (5.5 ±3.1) μg·m -3 , accounting for 22%, 21%, and 16% in PM 2.5 , respectively. The proportions of NO 3 - (27%) and SO 4 2- (23%) in PM 2.5 , respectively, increased with the increase in PM 2.5 and O 3 concentration. In addition, the proportions of NO 3 - and NH 4 + increased under low wind speed, high humidity, low temperature, and rainfall conditions. Moreover, the proportion of NO 3 - showed a daily variation characteristic of high at night and low during the day, whereas the opposite was true for SO 4 2- . The gas-particle partitioning process of NH 4 NO 3 was the main factor affecting the concentrations of NO 3 - and NH 4 + in PM 2.5 . Low temperature, high humidity, and high aerosol water content concentrations favored the partitioning of HNO 3 and NH 3 to the particulate phase. High pH also favored the partitioning of gas-phase HNO 3 to NO 3 - ; however, it was not conducive to the partition of NH 3 to NH 4 + . These trends partially explained the increase in the concentration and proportion of NO 3 - in PM 2.5 under different scenarios.

To investigate the change characteristics of secondary inorganic ions in PM 2.5 at different pollution stages before and after COVID-19, the online monitoring of winter meteorological and atmospheric pollutant concentrations in Zhengzhou from December 15, 2019 to February 15, 2020 was conducted using a high-resolution (1 h) online instrument. This study analyzed the causes of the haze process of COVID-19, the diurnal variation characteristics of air pollutants, and the distribution characteristics of air pollutants at different stages of haze.The results showed that Zhengzhou was mainly controlled by the high-pressure ridge during the haze process, and the weather situation was stable, which was conducive to the accumulation of air pollutants. SNA was the main component of water-soluble ions, accounting for more than 90%. Home isolation measures during COVID-19 had different impacts on the distribution characteristics of air pollutants in different haze stages. After COVID-19, the concentration of PM 2.5 in the clean, occurrence, and dissipation stages increased compared with that before COVID-19 but significantly decreased in the development stage. The home isolation policy significantly reduced the high value of PM 2.5 . The concentrations of NO 2 , SO 2 , NH 3 , and CO were the highest in the haze development stage, showing a trend of first increasing and then decreasing. The concentration of O 3 was lowest in the pre-COVID-19 development stage but highest in the post-COVID-19 development stage. The linear correlation between[NH 4 + ]/[SO 4 2- ] and[NO 3 - ]/[SO 4 2- ] at different time periods before and after COVID-19 was strong, indicating that the home isolation policy of COVID-19 did not change the generation mode of NO 3 - , and the corresponding reaction was always the main generation mode of NO 3 - . The correlation between[excess-NH 4 + ] and[NO 3 - ] was high in different periods before COVID-19, and NO 3 - generation was related to the increase in NH 3 or NH 4 + in the process of PM 2.5 pollution in Zhengzhou.

In recent years, complex air pollution with the characteristic pollutant of PM 2.5 has remained serious in China. Long term exposure to PM 2.5 might harm residential health and can increase premature death from specific diseases. The annual average concentration of PM 2.5 in Zhengzhou was much higher than the national secondary standard, which has an extremely negative impact on the health of residents. Based on the high spatial resolution grids of population density established through web-crawling and outdoor monitoring concentrations and urban residential emissions used to evaluate PM 2.5 exposure concentration, the exposure concentration of PM 2.5 for urban residents of Zhengzhou was assessed, considering both indoor and outdoor exposures. Relevant health risks were quantified with the integrated exposure-response model. Finally, the contributions of various reducing measures and different standards of air quality to the decreases in PM 2.5 exposure concentration were analyzed. The results showed that in 2017 and 2019, the time weighted exposure concentrations of PM 2.5 for Zhengzhou's urban residents were 74.06 μg·m -3 and 60.64 μg·m -3 , respectively, which was decreased by 18.12%. In addition, the mass fractions of the indoor exposure concentrations in the time weighted exposure concentrations were 83.58% and 83.01%, and its contribution to the drop of the time weighted exposure concentrations was 84.06%. In 2017 and 2019, the numbers of premature deaths attributed to PM 2.5 exposures for urban residents of Zhengzhou over the age of 25 were 13285 and 10323, respectively, showing a 22.30% decrease. By using these comprehensive measures, PM 2.5 exposure concentration for Zhengzhou's urban residents could be reduced by 86.23% at most, and 8902 premature deaths could be avoided.

From July 2020 to June 2021, monthly offline sampling of atmospheric VOCs was carried out and analyzed at three urban sites and one suburban site in Zhengzhou. Then, the volume fraction levels, composition characteristics, reactivity, and source apportionment of atmospheric VOCs were discussed. The results showed that the volume fraction of atmospheric VOCs in Zhengzhou was (37.50±14.30)×10 -9 during the sampling period, and the proportion of components was represented by alkanes (33%)>OVOCs (24%)>halogenated hydrocarbons (23%)>aromatic hydrocarbons (8%)>alkenes (7%)>alkynes (4%)>sulfides (1%). The seasonal variation characteristics were winter>autumn>summer>spring, and the monthly average value of VOCs had the highest value in January and the lowest value in May; the spatial variation characteristics were Zhengzhou University (ZD)>Jiancezhan (JCZ)>Jingkaiqu (JKQ)>Gangli Reservoir (GLR). The average·OH loss rate ( L ·OH ) was 4.24 s -1 , and the average ozone formation potential (OFP) was 172.27 μg·m -3 ; the top ten species of L ·OH and OFP at each site and in each season were dominated by alkenes, OVOCs, and aromatic hydrocarbons. The results of positive matrix factorization (PMF) showed that the main sources of VOCs were vehicle emissions (28%), solvent utilization (24%), industrial emissions (24%), and oil and gas volatilization (19%) and plant emissions (5%).