Single-atom catalysts based on polarization switching of ferroelectric In_(2)Se_(3) for N_(2) reduction

The polarization switching plays a crucial role in controlling the final products in the catalytic pro-cess.The effect of polarization orientation on nitrogen reduction was investigated by anchoring transition metal atoms to form active centers on ferroelectric material In_(2)Se_(3).During the polariza-tion switching process,the difference in surface electrostatic potential leads to a redistribution of electronic states.This affects the interaction strength between the adsorbed small molecules and the catalyst substrate,thereby altering the reaction barrier.In addition,the surface states must be considered to prevent the adsorption of other small molecules(such as *O,*OH,and *H).Further-more,the V@↓-In_(2)Se_(3) possesses excellent catalytic properties,high electrochemical and thermody-namic stability,which facilitates the catalytic process.Machine learning also helps us further ex-plore the underlying mechanisms.The systematic investigation provides novel insights into the design and application of two-dimensional switchable ferroelectric catalysts for various chemical processes.

Effect of Ni content on the wear behavior of Al-Si-Cu-Mg-Ni/SiC particles composites

In recent years,the addition of Ni has been widely acknowledged to be capable of enhancing the mechanical properties of Al-Si alloys.However,the effect of Ni on the wear behaviors of Al-Si alloys and Al matrix composites,particularly at elevated temperat-ures,remains an understudied area.In this study,Al-Si-Cu-Mg-Ni/20wt%SiC particles(SiCp)composites with varying Ni contents were prepared by using a semisolid stir casting method.The effect of Ni content on the dry sliding wear behavior of the prepared compos-ites was investigated through sliding tests at 25 and 350℃.Results indicated that theθ-Al_(2)Cu phase gradually diminished and eventually disappeared as the Ni content increased from 0wt%to 3wt%.This change was accompanied by the formation and increase inδ-Al_(3)CuNi andε-Al_(3)Ni phases in microstructures.The hardness and ultimate tensile strength of the as-cast composites improved,and the wear rates of the composites decreased from 5.29×10^(−4)to 1.94×10^(−4)mm^(3)/(N∙m)at 25℃and from 20.2×10^(−4)to 7×10^(−4)mm^(3)/(N∙m)at 350℃with the increase in Ni content from 0wt%to 2wt%.The enhancement in performance was due to the presence of strengthening network structures and additional Ni-containing phases in the composites.However,the wear rate of the 3Ni composite was approximately two times higher than that of the 2Ni composite due to the fracture and debonding of theε-Al_(3)Ni phase.Abrasive wear,delamination wear,and oxidation wear were the predominant wear mechanisms of the investigated composites at 25℃,whereas delamination wear and oxid-ation wear were dominant during sliding at 350℃.

Scaling law of hydrogen evolution reaction for InSe monolayer with 3d transition metals doping and strain engineering

Recently, two dimensional In Se attracts great attentions as potential hydrogen production photocatalysts.Here, comprehensive investigations on the hydrogen evolution reaction activity of In Se monolayer with3 d transition metal doping and biaxial strain were performed based on the density functional theory.Transition metal dopants significantly increase the bonding strength between H and Se, and then adjust the hydrogen adsorption free energy to 0.02 e V by Zn doping. The enhanced hydrogen evolution reaction activity results from less electron occupying H 1 s-Se 4 pzanti-bonding states, which is well correlated with the pzband center level. Importantly, the universal scalling law was proposed to descript the evolution of hydrogen adsorption free energy including both doping and strain effects. Moreover, with appropriate band alignment, optical absorption, and carriers separation ability, Zn doped In Se monolayer is considered as a promising candidate of visible-light photocatalyst for hydrogen production.

Unveiling spin magnetic effect of TM doped SnS_(2) nanosheet with enhanced hydrogen evolution reaction

Photoelectrochemical hydrogen evolution reaction(HER)is taken into account as an alternative to effective hydrogen production,emphasizing the importance of catalysts.The magnetism of catalysts could modulate the adsorption of the H atom and further enhance the HER activity.Herein,doping the double transition metal atoms on SnS_(2) nanosheet(TM_(2)@SnS_(2))to form the efficient magnetic catalyst is proposed to explore the spin magnetic effect on the HER performance.By performing first-principles calculations,nonmagnetic V_(2)@SnS_(2) is proved to be the candidate of the HER catalyst;nevertheless,the HER activities of antiferromagnetic and ferromagnetic V_(2)@SnS_(2) are relatively inferior due to the spin-induced charge redistribution.Meanwhile,machine learning analysis shows the absolute importance of the electronic structure of TM dopants and surrounding S ligands,and the HER activity could be predicted by the modified band centers of S-3p_(z) and TM-d.Furthermore,the proof-of-concept experiment has substantiated the above theoretical predictions by significantly increasing liner sweep voltammetry and photocurrent with applied magnetic field.This work provides a new avenue for uncovering the spin catalytic mechanism and the exploration and design of efficient HER catalysts.

Clinical characteristics and survival of 5283 esophageal cancer patients: A multicenter study from eighteen hospitals across six regions in China

Objective:This study aimed to investigate the potential determining epidemiological and clinical risk factors affecting the survival of esophageal cancer(EC)patients across multiple hospitals in China.Methods:This was a multicenter study comprising of newly diagnosed EC cases from Beijing,Hebei,Henan,Hubei,Zhejiang,and Guangdong Province of China.Their baseline characteristics and treatment methods data were collected from their medical records.The EpiData software was used for data quality control.The Kaplan-Meier method was used to estimate their overall survival(OS),and the Cox’s proportional hazard regression model was used to estimate hazard ratios(HR)and 95%confidence interval(CI).Results:The 3-and 5-year OS rates of the 5283 investigated EC patients were 49.98%and 39.07%,respectively.Their median survival was 36.00 months.The median survival time of females was longer than that of males(females vs.males:45.00 vs.33.00,P<0.001).The 5-year OS rate of patients who never-smoked was higher than that of smokers(never-smokers vs smokers:40.73%vs.37.84%,P=0.001).There was no significant difference in the 5-year OS rate between drinkers and never-drinkers(drinkers vs never-drinkers:34.22%vs.29.65%,P=0.330).In multivariate analysis,pathological stage(stage II:HR=1.80,95%CI=1.40-2.31;stage III:HR=2.62,95%CI=2.06-3.34;stage IV:HR=3.90,95%CI=2.98-5.09),poor differentiation/undifferentiated(HR=1.34,95%CI=1.11-1.63),not married status(HR=2.45,95%CI=1.49-4.04),production and service personnel(HR=1.36,95%CI=1.01-1.83)and farming/fishing(HR=1.40,95%CI=1.12-1.76)were independent prognostic risk factors for poor EC survival.Tumors in the thoracic or abdominal part of the esophagus,female and family history of any cancer were independent factors predictive of a good EC OS.Conclusion:Gender,marital status,occupation,family history of any cancer,tumor topographical site,differentiation status,and pathological stage were associated with the survival rate of EC.This study reveals important clinical characteristics of esophageal cancer patients in China and provides helpful information for their clinical management and surveillance.

Enhanced domain wall conductivity in photosensitive ferroelectrics Sn_(2)P_(2)S_(6) with full-visible-spectrum absorption

Recent optical stimulation suggests a vital non-contact pathway to manipulate both macroscopic and microscopic ferroelectric properties and paves the foundation for optoelectronics devices.However,up to date,most optical-related manipulation of ferroelectric properties is restricted due to their intrinsic bandgap and limited visible light spectrum absorption.Here,we reveal non-oxide Sn_(2)P_(2)S_(6) single crystal possesses full-visible-spectrum absorption(from 300 to 800 nm)with a unique disproportionation mechanism of photoexcited Sn ions and Urbach tail,which is not contradicting to the intrinsic band gap.Interestingly,we observed the existence of conductive domain walls(c-DW)and the light illumination induced significant enhancement of the domain wall conductivity caused by such disproportionation reaction.In addition,the domains separated by c-DW also exhibited noticeable electrical conductivity difference in the presence of optical illumination owing to the interfacial polarization charge with opposite signs.The result provides a novel opportunity for understanding the electrical conductivity behavior of the domains and domain walls in ferroelectrics with full-visible-spectrum absorption and achieving greatly enhanced performances for optoelectronics.

Bmelo12,an elongase of very long-chain fatty acids gene,regulates silk yield in Bombyx mori

In silkworm,cocoon shell weight(CSW),an index of silk yield,is a quantitative trait(Nagaraju and Goldsmith,2002),and multiple quantitative trait loci(QTLs)located on different chromosomes have been found(Zhan et al.,2009;Zhang et al.,2010;Li et al.,2015;Fang et al.,2020).

Camera Calibration Method Based on Self-made 3D Target

A camera calibration algorithm based on self-made target is proposedin this paper, which can solve the difficulty of making high precision 3Dtarget. Theself-made target consists of two intersecting chess board. With the classic scalemethod, the 3D coordinates of selected points in the target were derived from thedistance matrix. The element in distance matrix is the distance between every twopoints, which can be obtained by measurement. The spatial location precision ofpoints in the target was ensured by measurement instead of manufacturing, whichreduced the production cost and the requirements for the production accuracygreatly. Camera calibration was completed using 3D target based method. It canbe further extended to the applications where the target cannot be produced. Theexperimental results show the validity of this method.