Synergism of preintercalated manganese ions and lattice water in vanadium oxide cathodes for high-capacity and long-life Zn-ion batteries

Aqueous Zn-ion batteries(AZIBs)are recognized as a promising energy storage system with intrinsic safety and low cost,but its applications still rely on the design of high-capacity and stable-cycling cathode materials.In this work,we present an intercalation mechanism-based cathode materials for AZIB,i.e.the vanadium oxide with pre-intercalated manganese ions and lattice water(noted as MVOH).The synergistic effect between Mn^(2+)and lattice H_(2)O not only expands the interlayer spacing,but also significantly enhances the structural stability.Systematic in-situ and ex-situ characterizations clarify the Zn^(2+)/H^(+)co–(de)intercalation mechanism of MVOH in aqueous electrolyte.The demonstrated remarkable structure stability,excellent kinetic behaviors and ion-storage mechanism together enable the MVOH to demonstrate satisfactory specific capacity of 450 mA h g^(−1)at 0.2 A g^(−1),excellent rate performance of 288.8 mA h g^(−1)at 10 A g^(−1)and long cycle life over 20,000 cycles at 5 A g^(−1).This work provides a practical cathode material,and contributes to the understanding of the ion-intercalation mechanism and structural evolution of the vanadium-based cathode for AZIBs.

Facies-controlled prediction of dolomite reservoirs in the Middle Permian Qixia Formation in Shuangyushi,northwestern Sichuan Basin

The Middle Permian Qixia Formation in the Shuangyushi area,northwestern Sichuan Basin,develops shoal-facies dolomite reservoirs.To pinpoint promising reservoirs in the Qixia Formation,deep thin shoal-facies dolomite reservoirs were predicted using the techniques of pre-stack Kirchhoff-Q compensation for absorption,inverse Q filtering,low-to high-frequency compensation,forward modeling,and facies-controlled seismic meme inversion.The results are obtained in six aspects.First,the dolomite reservoirs mainly exist in the middle and lower parts of the second member of Qixia Formation(Qi2 Member),which coincide with the zones shoal cores are developed.Second,the forward modeling shows that the trough energy at the top and bottom of shoal core increases with increasing shoal-core thickness,and weak peak reflections are associated in the middle of shoal core.Third,five types of seismic waveform are identified through waveform analysis of seismic facies.Type-I and Type-II waveforms correspond to promising facies(shoal core microfacies).Fourth,vertically,two packages of thin dolomite reservoirs turn up in the sedimentary cycle of intraplatform shoal in the Qi2 Member,and the lower package is superior to the upper package in dolomite thickness,scale and lateral connectivity.Fifth,in plane,significantly controlled by sedimentary facies,dolomite reservoirs laterally distribute with consistent thickness in shoal cores at topographical highs and extend toward the break.Sixth,the promising prospects are the zones with thick dolomite reservoirs and superimposition of horstegraben structural traps.

In situ induced cation-vacancies in metal sulfides as dynamic electrocatalyst accelerating polysulfides conversion for Li-S battery

Cation vacancy engineering is considered to be one of the effective methods to solve the issues of shuttling and sluggish redox kinetics of Li PSs owing to the intrinsic tunability of electronic structure.However,cation vacancies are few studied in the Li-S realm due to their complex and rigid preparation methods.In this work,one-step pyrolysis is reported to in situ introduce Fe-vacancies into iron sulfide(Fe_(0.96)S)as a sulfur host.For this host structure,Fe_(0.96)S is first employed as an adsorbent and catalyst in Li-S system.During the carbonization process,a tight contact structure of Fe_(0.96)S crystal and carbon network(Fe_(0.96)S@C)is in situ constructed,and the carbon layer as a conductor provides smooth electrons transfer pathways for redox reactions.Meanwhile,due to the introduction of Fe-vacancies in Fe S crystal,the adsorption capability and catalytic effect for Li PSs have been substantially enhanced.Moreover,the presence of Fe_(0.96)S crystal favors the mobility of electron and diffusion of Li+,which is revealed by the experiments and theoretical calculations.Through synergy respective advantages effect of Fe_(0.96)S and carbon,the Fe_(0.96)S@C-S cathode delivers high-rate capability at 5.0 C and stable long-life performance.Even under a high sulfur loading of 3.5 mg/cm^(2),the durable cyclic stability is still exhibited with the capacity retention of 93%over 400 cycles at 1.0 C,and the coulombic efficiency is≥98%.Noting that this strategy greatly simplifies the synthetic process of currently known cation-vacancy materials and furnishes a universal mentality for designing both divinable and astonishing new cation-vacancy materials.

Molecular dynamics simulation on the effect of dislocation structures on the retention and distribution of helium ions implanted into silicon

To investigate the effect of dislocation structures on the initial formation stage of helium bubbles, molecular dynamics(MD) simulations were used in this study. The retention rate and distribution of helium ions with 2 ke V energy implanted into silicon with dislocation structures were studied via MD simulation. Results show that the dislocation structures and their positions in the sample affect the helium ion retention rate. The analysis on the three-dimensional distribution of helium ions show that the implanted helium ions tend to accumulate near the dislocation structures. Raman spectroscopy results show that the silicon substrate surface after helium ion implantation displayed tensile stress as indicated by the blue shift of Raman peaks.

Mechanism and Research Progress of Fuyang Huoxue Jiedu Formula against Recurrence of Ulcerative Colitis

By introducing the composition and modern pharmacology of Fuyang Huoxue Jiedu Formula,the paper further explored the mechanism and research progress of Fuyang Huoxue Jiedu Formula against recurrence of ulcerative colitis(UC).The formula can effectively improve the TCM syndromes of UC patients,reduce the recurrence rate,and improve clinical efficacy and patients’quality of life.

Spatial spillover effects of official development assistance on environmental pressure in sub-Saharan African(SSA)countries

Impoverished sub-Saharan Africa(SSA)is under increasing environmental pressure from global environmental changes.It is now generally accepted in academic circles that economic development in SSA countries can cause environmental pressure in other countries.However,there is research gap on the impact of economic assistance on environmental pressure in SSA countries and whether economic assistance causes spatial spillovers of environ-mental pressure between SSA countries.To better understand the impact of economic assistance on environmental pressures in SSA,a dynamic spatial Dubin panel model was developed.It helped us explore the spatial spillover effects of economic assistance on environmental pressures in recipient countries based on the panel data from 34 SSA countries.The results show that economic assistance had a positive stimulating effect on environmen-tal pressures of recipient countries,which means that the degree of human disturbance to the environment has deepened.Due to the regional correlation effect,neighboring countries were saddled with environmental pres-sures from the target country.Moreover,environmental pressures have time inertia,which can easily produce a snowball effect.The decomposition of effects shows that the impact of economic assistance on environmental pressures is relatively minor.Environmental pressures have spillover effects,so to deal with diffuse risks,joint regional prevention and control policies should be developed.

A Morphology-Driven Method for Measuring Technology Complementarity:Empirical Study Involving Alzheimer’s Disease

Purpose:Measuring the exact technology complementarity between different institutions is necessary to obtain complementary technology resources for R&D cooperation.Design/methodology/approach:This study constructs a morphology-driven method for measuring technology complementarity,taking medical field as an example.First,we calculate semantic similarities between subjects(S and S)and action-objects(AO and AO)based on the Metathesaurus,forming clusters of S and AO based on a semantic similarity matrix.Second,we identify key technology issues and methods based on clusters of S and AO.Third,a technology morphology matrix of several dimensions is constructed using morphology analysis,and the matrix is filled with subjects-action-objects(SAO)structures according to corresponding key technology issues and methods for different institutions.Finally,the technology morphology matrix is used to measure the technology complementarity between different institutions based on SAO.Findings:The improved technology complementarity method based on SAO is more of a supplementary and refined framework for the traditional IPC method.Research limitations:In future studies we will reprocess and identify the SAO structures which were not in the technology morphology matrix,and find other methods to characterize key technical issues and methods.Furthermore,we will add the comparison between proposed method and traditional and mostly used complementarity measurement method based on industry chain and industry code.Practical implications:This study takes medical field as an example.The morphology-driven method for measuring technology complementarity can be migrated and applied for any given field.Originality/value:From the perspective of complementary technology resources,this study develops and tests a more accurate morphology-driven method for technology complementarity measurement.

Emissive metallacages for biomedical applications

Owing to their appealing three-dimensional structures and tunable photophysical properties, emissive metallacages have been widely applied in recognition and sensing, adsorption and separation, catalysis, etc. Recently, the application of emissive metallacages in biomedical fields has emerged as a hot research topic, because multiple biological functionalities can be facilely integrated into metallacage-based platforms to deliver different functions. In this review, the applications of emissive metallacages in bio-imaging, delivery and cancer theranostics are systematically summarized. The dilemmas and challenges of metallacage-based biomedical materials are also raised at the end of this review. We hope this review would provide some guidance for the construction of novel emissive metallacages with biological functions, and further advance the development of emissive metallacages as biomedical materials.

Enhancing the Photosensitivity of Hypocrellin A by Perylene Diimide Metallacage‑Based Host–Guest Complexation for Photodynamic Therapy

The development of supramolecular hosts which can efficiently encapsulate photosensitizers to improve the photodynamic efficacy holds great promise for cancer therapy.Here,we report two perylene diimide-based metallacages that can form stable host–guest complexes with planar conjugated molecules including polycyclic aromatic hydrocarbons and photosensitizers(hypocrellin A).Such host–guest complexation not only prevents the aggregation of photosensitizers in aqueous environments,but also offers fluorescence resonance energy transfer(FRET)from the metallacage to the photosensitizers to further improve the singlet oxygen generation(Φ_(Δ)=0.66).The complexes are further assembled with amphiphilic polymers,forming nanoparticles with improved stability for anticancer study.Both in vitro and in vivo studies indicate that the nanoparticles display excellent anticancer activities upon light irradiation,showing great potential for cancer photodynamic therapy.This study provides a straightforward and effective approach for enhancing the photosensitivity of conventional photosensitizers via host–guest complexation-based FRET,which will open a new avenue for host–guest chemistry-based supramolecular theranostics.

Geometric morphometric analysis of Eysarcoris guttiger,E.annamita and E.ventralis(Hemiptera:Pentatomidae)

The genus Eysarcoris can be easily distinguished from other genera through the two spots in the basal angle of the scutellum. Nevertheless, Eysarcoris species show complex variances. Geometric morphometric methods have been increasingly applied to distinguish species and to define the boundary of genera among insects. In the present study, geometric morphometric approach was firstly employed to evaluate the shape variation of three characters （fore wing, hind wing and pygophore） of E. guttiger, E. annamita and E. ventralis using E. aeneus as outgroup to ascertain whether this approach is a reliable method for the taxonomy of Eysarcoris. Analysis was conducted on the landmarks of the three characters of these species. Multivariate regression of procrustes coordinates against centroid size was conducted to test the presence of allometry. Principal component analysis （PCA）, canonical variate analysis （CVA） and cluster analysis were utilized to describe variations in shapes among the studied species. For all of the three characters, though PCA analysis showed some overlap among species, p-values for procrustes distance and mahalanobis distance were all less than 0.0001. The distribution of the three studied species corresponds with their species status. This study demonstrates that the geometric morphometrics of both the fore wing and the hind wing might represent a possible tool for the identification of species within this genus.

Current status,trends,and predictions in the burden of gallbladder and biliary tract cancer in China from 1990 to 2019

Background:Gallbladder and biliary tract cancer(GBTC)has greatly damaged the health of patients and is accompanied by a dismal prognosis.The worldwide distribution of GBTC shows extensive variance and the updated data in China is lacking.This study was to determine the current status,trends,and predictions in the burden of GBTC over the past 30 years in China.Methods:This was a descriptive,epidemiological,secondary analysis of the Global Burden of Disease,Injuries,and Risk Factor Study 2019 data.Data including incidence,prevalence,mortality,and disability-adjusted life years(DALYs)of GBTC in China by year,age,and sex were assessed.Joinpoint regression analysis was conducted to evaluate trends of disease burden due to GBTC from 1990 to 2019.Nordpred age-period-cohort analysis was applied for the projection of mortality and incidence due to GBTC from 2019 to 2044.Results:Nationally,there were 38,634(95%uncertainty interval[UI]:27,350-46,512)new cases and 47,278(95%UI:32,889-57,229)patients due to GBTC,causing 34,462(95%UI:25,220-41,231)deaths,and 763,584(95%UI:566,755-920,493)DALYs in 2019.Both cases and rates of burden owing to GBTC were heavier among males and at old age.From 1990 to 2019,the age-standardized rates of incidence,prevalence,mortality,and DALYs of GBTC generally increased from 1990 to 2019,with average annual percentage change at 0.8%(95%confidential interval[CI]:0.6-1.0%),1.3%(95%CI:1.1-1.5%),0.4%(95%CI:0.2-0.6%),and 0.2%(95%CI:0.1-0.4%),respectively.Even though the age-standardized incidence rate and agestandardized mortality rate in both sexes were predicted to decline gradually from 2019 to 2044,the number of new cases and deaths were expected to grow steadily.Conclusions:GBTC is becoming a major health burden in China,particularly among males and older individuals.Given the aging population and increasing burden,effective strategies and measurements are urged to prevent or reduce the number of new cases and deaths of GBTC.

XGRouter： high-quality global router in X-architecture with particle swarm optimization

This paper presents a high-quality very large scale integration （VLSI） global router in X-architecture, called XGRouter, that heavily relies on integer linear pro- gramming （ILP） techniques, partition strategy and particle swarm optimization （PSO）. A new ILP formulation, which can achieve more uniform routing solution than other formu- lations and can be effectively solved by the proposed PSO is proposed. To effectively use the new ILP formulation, a partition strategy that decomposes a large-sized problem into some small-sized sub-problems is adopted and the routing re- gion is extended progressively from the most congested re- git）n. In the post-processing stage of XGRouter, maze rout- ing based on new routing edge cost is designed to further optimize the total wire length and mantain the congestion uniformity. To our best knowledge, XGRouter is the first work to use a concurrent algorithm to solve the global rout- ing problem in X-architecture. Experimental results show that XGRouter can produce solutions of higher quality than other global routers. And, like several state-of-the-art global touters, XGRouter has no overflow.

An MCIA-like complex is required for mitochondrial complex Ⅰ assembly and seed development in maize

During adaptive radiation,mitochondria have co-evolved with their hosts,leading to gain or loss of subunits and assembly factors of respiratory complexes.Plant mitochondrial complex Ⅰ harbors40 nuclearand 9 mitochondrial-encoded subunits,and is formed by stepwise assembly during which different intermediates are integrated via various assembly factors.In mammals,the mitochondrial complex Ⅰ intermediate assembly(MCIA)complex is required for building the membrane arm module.However,plants have lost almost all of the MCIA complex components,giving rise to the hypothesis that plants follow an ancestral pathway to assemble the membrane arm subunits.Here,we characterize a maize crumpled seed mutant,crk1,and reveal by map-based cloning that CRK1 encodes an ortholog of human complex Ⅰ assembly factor 1,zNDUFAF1,the only evolutionarily conserved MCIA subunit in plants.zNDUFAF1 is localized in the mitochondria and accumulates in two intermediate complexes that contain complex Ⅰ membrane arm subunits.Disruption of zNDUFAF1 results in severe defects in complex Ⅰ assembly and activity,a cellular bioenergetic shift to aerobic glycolysis,and mitochondrial vacuolation.Moreover,we found that zNDUFAF1,the putative mitochondrial import inner membrane translocase ZmTIM17-1,and the isovaleryl-coenzyme A dehydrogenase ZmIVD1 interact each other,and could be co-precipitated from the mitochondria and co-migrate in the same assembly intermediates.Knockout of either ZmTIM17-1 or ZmIVD1 could lead to the significantly reduced complex Ⅰ stability and activity as well as defective seeds.These results suggest that zNDUFAF1,ZmTIM17-1 and ZmIVD1 probably form an MCIA-like complex that is essential for the biogenesis of mitochondrial complex Ⅰ and seed development in maize.Our findings also imply that plants and mammals recruit MCIA subunits independently for mitochondrial complex Ⅰ assembly,highlighting the importance of parallel evolution in mitochondria adaptation to their hosts.

Pd/C modified with Sn catalyst for liquid-phase selective hydrogenation of maleic anhydride to gamma-butyrolactone

Pd catalysts suffered from poor selectivity and stability for liquid-phase hydrogenation of maleic anhydride（MA） to gamma-butyrolactone（GBL）.Thus,Pd/C catalysts modified with different Sn loadings were synthesized,and characterized by XRD,XPS,TEM and elemental mapping.The types of alloy phase and the amounts of the surface Pd-SnOx sites altered along with Sn/Pd mass ratios from 0-1.0synthesized in the process of preparation.The maximum reaction rate was 0.57 mol-GBL/（mol-Pd min）and selectivity was 95.94%when the Sn/Pd mass ratio was 0.6.It might be attributed to the formation of Pd2Sn alloy and less amounts of Pd-SnOx sites.

Development of a new index for automated mapping of ratoon rice areas using time-series normalized difference vegetation index imagery

Over recent decades, the global demand for food has continued to grow, owing to population growth and the loss of arable land. Rice ratooning offers new opportunities for increasing rice production and has received renewed interest because of the minimal additional labor input required for its adoption. Regular, regional-scale monitoring of the spatial patterns of both traditional and ratoon rice cropping systems provides essential information for agricultural resource management and food security studies. However, the similar phenological characteristics of traditional double rice and ratoon rice cropping systems make it challenging to accurately classify these cropping practices based on satellite observations alone. In this study, we first proposed an improved phenology-based rice cropping area detection algorithm using moderate resolution imaging spectroradiometer (MODIS) normalized difference vegetation index (NDVI) imagery. A new index, ratoon rice index, was then developed to automatically delineate ratoon rice cropping areas with the aid of a base map of rice in Hubei Province, China. The accuracy assessment using ground truth data showed that our approach could map both traditional and ratoon rice cropping areas with high user accuracy (91.25% and 91.43%, respectively). The MODIS-retrieved rice cropping areas were validated using annual agricultural census data, and coefficient of determination (R2) values of 0.60 and 0.41 were recorded for traditional and ratoon rice cropping systems, respectively. The total area of ratoon rice was estimated to be 1 283.6 km2, 5.0% of the total rice cropping area, in Hubei Province in 2016. These demonstrated the feasibility of extracting the spatial patterns of both traditional and ratoon rice cropping systems solely from time-series NDVI and field survey data and strides made in facilitating the timely and routine monitoring of traditional and ratoon rice distribution at subnational level. Given sufficient historical satellite and phenology records, the proposed algorithm had the potential to enhance rice cropping area mapping efforts across a broad temporal scale (e.g., from the 1980s to the present).

Adjustable crystalline stereocomplexes from enantiopure gradient polycarbonates

Stereoselective interaction was observed in the mixture of enantiopure gradient polycarbonate(denoted as PCOPC-g-PCPC, originated from the enantioselective terpolymerization of CO2, 3,4-epoxytetrahydrofuran(COPO) and cyclopentene oxide(CPO)) and various isotactic polycarbonates with opposite configuration in chloroform solution. The resultant crystalline stereocomplexes exhibit enhanced thermal stability and new crystalline behaviors, significantly distinct from their parent polymers. It was found that the cocrystallization selectively occurred between(R)-PCOPC(CO_2/COPO copolymer) and(S)-PCOPC-enriched segment in the gradient terpolymer(S)-PCOPC-g-PCPC, while(R)-PCPC(CO_2/CPO copolymer) selectively complexed with(S)-PCPC-enriched segment. No stereocomplexation was observed between(S)-PCOPC-g-PCPC and(S)-PCOPC or(S)-PCPC. This study is beneficial to finding new routes to prepare various semicrystalline materials having a wide variety of physical properties and degradability.

Photoluminescence and Raman Spectroscopy Study on Color Centers of Helium Ion-Implanted 4H-SiC

Color centers in silicon carbide(SiC)are promising candidates for quantum technologies.However,the richness of the polytype and defect configuration of SiC makes the accurate control of the types and position of defects in SiC still challenging.In this study,helium ion-implanted 4H-SiC was characterized by atomic force microscopy(AFM),confocal photoluminescence(PL),and confocal Raman spectroscopy at room temperature.PL signals of silicon vacancy were found and analyzed using 638-nm and 785-nm laser excitation by means of depth profiling and SWIFT mapping.Lattice defects(C-C bond)were detected by continuous laser excitation at 532 nm and 638 nm,respectively.PL/Raman depth profiling was helpful in revealing the three-dimensional distribution of produced defects.Differences in the depth profiling results and SRIM simulation results were explained by considering the depth resolution of the confocal measurement setup,helium bubbles,as well as swelling.

Graphdiyne anchoring to construct highly dense palladium trimer active sites for the selective hydrogenation of acetylene

Semi-hydrogenation of acetylene is of growing interest and popularity but subjects to a major challenge in selective hydrogenation to ethylene.Here,we report a strategy that uses graphdiyne(GDY)as a carrier to prepare single-cluster catalysts(SCCs),which on average clusters composed of three atoms(denoted as Pd3 trimer)and applied it to the acetylene semihydrogenation in the presence of large amounts of ethylene.Based on experimental results and systematic quantum chemical research and computational screening,we found that there are multiple active Pd structures on GDY and the Pd3 trimer anchored on GDY is a specific and durable cluster with great potential for accurate and efficient heterogeneous catalysis.The synergetic effects between neighboring atoms in Pd trimer guarantee easy desorption of ethylene and the absence of unselective hydride species thereby preventing excessive hydrogenation to generate unwanted byproducts,which is a crucial mechanism for the excellent selectivity of the catalyst.This new method for precise synthesis Pd clusters provides accurate ways for designing selective hydrogenation catalysts at the atomic scale.

Novel oxygen-enrichment method using annular air curtain for single-head roadway of plateau mine

The low-oxygen environment restricts the exploitation of mineral resources on plateaus and affects miner’s safety.This paper proposes an oxygen-enrichment method using an annular air curtain.Through numerical simulation and experiments,it was confirmed that the proposed method improves the breathing environment in the single-head roadway of a plateau mine.Computational fluid dynamics(CFD)was used to investigate the oxygen-enriching effect and oxygen spatial distribution regularities after using the proposed oxygen-enrichment method in the single-head roadway of a plateau mine.The reliability of the CFD model was confirmed by experiment.Orthogonal testing was conducted to investigate the influence degree and optimal level combination of factors influencing oxygen enrichment.The results demonstrate that the annular air curtain effectively prevented oxygen loss,thus forming a local oxygen-rich space and improving the effective utilization rate of oxygen.Oxygen supply concentration and velocity are positively correlated with the oronasal oxygen mass fraction through a linear function,while the air curtain outlet wind velocity is negatively correlated with the oronasal oxygen mass fraction through a linear function.The annular air curtain diameter and oronasal oxygen mass fraction do not have an obvious functional relationship.When the annular air curtain diameter was greater than 0.9 m,the oronasal oxygen mass fraction was stable at approximately 25.30%.The influencing factors of the novel oxygen-enrichment method are,in descending order,as follows:oxygen supply concentration,annular air curtain diameter,air curtain outlet wind velocity,and oxygen supply velocity.The optimal level combination is oxygen supply concentration of 100%,oxygen supply velocity of 11 m/s,air curtain outlet wind velocity of 1.5 m/s,and annular air curtain diameter of 0.9 m.