Tailoring NH_(4)^(+)storage by regulating oxygen defect in ammonium vanadate

Defect engineering is an effective strategy for modifying the energy storage materials to improve their electrochemical performance.However,the impact of oxygen defect and its content on the electrochemical performances in the burgeoning aqueous NH_(4)^(+)storage field remains explored.Therefore,for the first time in this work,an oxygen-defective ammonium vanadate[(NH_(4))_(2)V_(10)O_(25)·8H_(2)O,denoted as Od-NHVO]with a novel 3D porous flower-like architecture was achieved via the reduction of thiourea in a mild reaction condition,which is a facile method that can realize the intention to regulate the oxygen defect content,with the capability of mass-production.The as-prepared Od_M-NHVO with moderate oxygen defect content can deliver a stable specific capacitance output(505 F g^(-1),252 mAh g^(-1)at 0.5 A g^(-1)with~80% capacitance retention after 10,000 cycles),which benefits from extra active sites,unimpeded NH_(4)^(+)-migration path and relatively high structure integrity.In contrast,low oxygen defect content will lead to the torpid electrochemical reaction kinetics while too high content of it will reduce the chargestorage capability and induce structural disintegration.The superior NH_(4)^(+)-storage behavior is achieved with the reversible intercalation/deintercalation process of NH_(4)^(+)accompanied by forming/breaking of hydrogen bond.As expected,the assembled flexible OdM-NHVO//PTCDI quasi-solid-state hybrid supercapacitor(FQSS HSC)also exhibits high areal capacitance,energy density and reliable flexibility.This work provides a new avenue for developing materials with oxygen-deficient structure for application in various aqueous non-metal cation storage systems.

医学基础化学课程“模块化–主题”教学策略的构建与实践

基础化学是医学生最早接触的一门专业基础课,大多数学生在学习时仍然认为基础化学仅仅是高中化学课程内容的延伸和拓展,没有真正建立起基础化学课程与医学各专业课程的联系,因此对所学的内容兴趣不高,缺乏学习的主动性。本文提出了“模块化–主题”教学策略,并从教学内容、教学模式、教学反馈、教学评价等四个方面介绍“模块化–主题”教学策略的构建与实践经验。教学内容划分为溶液、胶体、热力学及动力学、电化学、物质结构与作用力、配位化合物和紫外光谱分析等七个教学模块。每个模块依据知识点提出若干个实用的“主题”,并且结合不同的“主题”教学内容采用不同的教学模式PBL (Problem-based learning)、TBL (Team-based learning)或CBL(Case-based learning)。设计教学调查问卷跟踪并反馈学生的学习状态和学习进度。从理解、应用、延展和联系四个教学评价指标评估学生的学习效果和掌握程度,并且为具有探索和创新能力的学生提供自我进一步学习的思路和方向。“模块化–主题”教学策略加深了基础化学课程和医学专业课程的衔接与融合,使基础化学教学能够适应现代医学科学发展,更好地为医学教育服务。

In situ confined vertical growth of Co_(2.5)Ni_(0.5)Si_(2)O_(5)(OH)_(4)nanoarrays on rGO for an efficient oxygen evolution reaction

Rational design of oxygen evolution reaction(OER)catalysts at low cost would greatly benefit the economy.Taking advantage of earth-abundant elements Si,Co and Ni,we produce a unique-structure where cobalt-nickel silicate hydroxide[Co_(2.5)Ni_(0.5)Si_(2)O_(5)(OH)_(4)]is vertically grown on a reduced graphene oxide(rGO)support(CNS@rGO).This is developed as a low-cost and prospective OER catalyst.Compared to cobalt or nickel silicate hydroxide@rGO(CS@rGO and NS@rGO,respectively)nanoarrays,the bimetal CNS@rGO nanoarray exhibits impressive OER performance with an overpotential of 307 mV@10 mA cm^(-2).This value is higher than that of CS@rGO and NS@rGO.The CNS@rGO nanoarray has an overpotential of 446 mV@100 mA cm^(-2),about 1.4 times that of the commercial RuO_(2)electrocatalyst.The achieved OER activity is superior to the state-of-the-art metal oxides/hydroxides and their derivatives.The vertically grown nanostructure and optimized metal-support electronic interactions play an indispensable role for OER performance improvement,including a fast electron transfer pathway,short proton/electron diffusion distance,more active metal centers,as well as optimized dualatomic electron density.Taking advantage of interlay chemical regulation and the in-situ growth method,the advanced-structural CNS@rGO nanoarrays provide a new horizon to the rational and flexible design of efficient and promising OER electrocatalysts.

Effective adsorptive denitrogenation from model fuels over yttrium ion-exchanged Y zeolite

The adsorption removal of indole and quinoline in octane with and without toluene over zeolites NaY and Yttrium Ion-exchanged Y(YY)using batch adsorption experiments was studied at 25℃and 0.1 MPa.YY was prepared by treating NaY with Y(NO3)3 solution twice via liquid ion-exchange method.NaY and YY were both characterized by XRD,SEM,N2 adsorption,XRF,NH3-TPD,and pyridine-FTIR techniques.Adsorption isotherms of indole,quinoline and toluene in octane were conducted at 25.0℃to explain the influence of toluene on nitrogen removal over NaY and YY.The partial destruct of the crystalline structure of NaY was observed after the introduction of yttrium ion,which led to an evident decline in BET surface area and pore volume of YY.Strong Br?nsted acidity and medium Lewis acidity were introduced by yttrium ion-exchange.Though the specific surface area and pore volume of YY were much lower than those of NaY,YY exhibited equivalent adsorption capacities for indole and quinoline as NaY in model fuels without toluene.In the presence of 20 vol%toluene,however,YY exhibited much higher adsorption capacities for indole and quinoline than NaY,especially in the case of quinoline.The improved toluene-tolerant of YY was ascribed to the strong acid–base interaction between YY and quinoline and the decreased adsorption strength between YY and toluene.

Adsorption desulfurization of model gasoline by metal–organic framework Ni3（BTC）2

This work presented the synthesis of Ni-based metal-organic framework material with a paddle-wheel structure Ni3(BTC)2 (Ni-BTC) and its application in thiophene (TP) adsorption from gasoline distillate by batch method. Adsorption isotherms of TP, cyclohexene, and toluene in cyclohexane onto Ni-BTC were conducted at 298-308 K to interpret the different effect of cyclohexene and toluene on TP adsorption. The results showed that, compared w让h cyclohexene, toluene addition in model gasoline led to a more evident decline in sulfur capacity of Ni-BTC, which is opposite to isostructural HKUST-1. The adsorption isotherms of TP, cyclohexene and toluene fit Langmuir model, S-type model and Temkin model well, respectively, indicating that the adsorption mechanisms of TP and the two competitors are different from one another The adsorption capacities on Ni-BTC followed the order of cyclohexene < toluene < TP at the same equilibrium concentrations, implying the order of the adsorption affinities, which is in good agreement with the different extent of influence by the two competitors. The enthalpy of TP adsorption on Ni-BTC was estimated to be -80.01 kj/mol, almost twice that on HKUST-1. The poor reusability of Ni-BTC in batch experiment, which is owing to its sensitivity to the air, can be prevented from regenerating used Ni-BTC in fixed-bed reactor by N2 flow. The difference between Ni-BTC and HKUST-1 in maximum adsorption capacity (q0),△H of TP adsorption, and stability demonstrates that the central metal in isostructural MOFs plays a key role in adjusting the desulfurization performance, which may open up a potential avenue for the development of MOF-based adsorbents with superior desulfurization performance.

Weak base favoring the synthesis of highly ordered V-MCM-41 with well-dispersed vanadium and the catalytic performances on selective oxidation of benzyl alcohol

The key to improve the performance of heteroatom catalysts is to ensure the orderliness of catalysts and the good dispersion of heteroatoms.The alkalinity plays the indispensable role in synthetic process of V-MCM-41 catalyst.The excessive alkalinity of synthetic system will make the MCM-41 difficult to crystallize,even to dissolve.It is easy to accumulate for heteroatomic species in the system of low alkalinity.Herein,the highly ordered VMCM-41 with high vanadic content in framework is synthesized in the condition of excessive NH3·H2 O in this paper.A series of characterization results prove the good dispersion of vanadium species,and most of vanadium gets into the framework of MCM-41 with the states of tetravalence and pentavalence.Furthermore,the modified MCM-41 by other transition metals is successful synthesized by the method of V-MCM-41 in this paper.The VMCM-41 shows well catalytic activity for the selective oxidation of benzyl alcohol,which up to 74.83%for the conversion of benzyl alcohol and 96.20%for selectivity of benzaldehyde when initial V/Si=0.10.The paper provides the possibility for industrial application of V-MCM-41 in the oxidation of benzyl alcohol for benzaldehyde.Besides,the work provides a significant idea for the synthesis of modified MCM-41 by well-dispersed transition metals.

Quench-tailored Al-doped V_(2)O_(5) nanomaterials for efficient aqueous zinc-ion batteries

Rechargeable aqueous zinc-ion batteries(ZIBs)are regarded as a promising competition to lithium-ion batteries as energy storage devices,owing to their high safety and low cost.However,the development of high-performance ZIBs is largely hindered by the shortage of ideal cathode materials with high-rate capability and long-cycle stability.Herein,we address this bottleneck issue by the quenching-tailored surface chemistry of V_(2)O_(5) cathode nanomaterial.By rapid quenching from high temperatures,Al ions are doped into V_(2)O_(5) lattice(Al-V_(2)O_(5))and abundant oxygen vacancies are formed on the surface/nearsurface,which facilitate the desired rapid electron transfers.Our density functional theory(DFT)simulations elucidate that the doping of Al ions into V_(2)O_(5) remarkably reduces the Zn^(2+)-diffusion barriers and improves the electrical conductivity of V_(2)O_(5).As a proof-of-concept application,the thus-optimized AlV_(2)O_(5) cathode delivers a superior specific capacity of 532 m Ah g^(-1) at 0.1 A g^(-1) and a long-cycling life with76%capacity retention after 5000 cycles,as well as a good rate performance.This work provides not only a novel strategy for tuning the surface chemistry of V_(2)O_(5) to boost the Zn^(2+)storage but also a general pathway of modifying metal oxides with improved electrochemical performance.

Better engineering layered vanadium oxides for aqueous zinc‐ion batteries: Going beyond widening the interlayer spacing

Aqueous zinc‐ion batteries(ZIBs)are regarded as among the most promising candidates for large‐scale grid energy storage,owing to their high safety,low costs,and environmental friendliness.Over the past decade,vanadium oxides,which are exemplified by V2O5,have been widely developed as a class of cathode materials for ZIBs,where the relatively high theoretical capacity and structural stability are among the main considerations.However,there are considerable challenges in the construction of vanadium‐based ZIBs with high capacity,long lifespan,and excellent rate performance.Simple widenings of the interlayer spacing in the layered vanadium oxides by pre‐intercalations appear to have reached their limitations in improving the energy density and other key performance parameters of ZIBs,although various metal ions(Na+,Ca2+,and Al3+)and even organic cations/groups have been explored.Herein,we discuss the advances made more recently,and also the challenges faced by the high‐performance vanadium oxides(V2O5‐based)cathodes,where there are several strategies to improve their electrochemical performance ranging from the new structural designs down to sub‐nano‐scopic/molecular/atomic levels,including cation pre‐intercalation,structural water optimization,and defect engineering,to macroscopic structural modifications.The key principles for an optimal structural design of the V2O5‐based cathode materials for high energy density and fast‐charging aqueous ZIBs are examined,aiming at paving the way for developing energy storage designed for those large scales,high safety,and low‐cost systems.

Adjusting oxygen vacancy of VO_(2)·xH_(2)O nanoarray architectures for efficient NH_(4)^(+) storage

Aqueous rechargeable batteries are the promising energy storge technology due to their safety,low cost,and environmental friendliness.Ammonium ion(NH_(4)^(+))is an ideal charge carrier for such batteries because of its small hydration radius and low molar mass.In this study,VO_(2)·xH_(2)O with rich oxygen defects(d-HVO)is designed and synthesized,and it exhibits unique nanoarray structure and good electrochemical performances for NH_(4)^(+)storge.Experimental and calculation results indicate that oxygen defects in d-HVO can enhance the conductivity and diffusion rate of NH_(4)^(+),leading to improved electrochemical performances.The most significant improvement is observed in d-HVO with 2 mmol thiourea(d-HVO-2)(220 mAh·g^(-1) at 0.1 A·g^(-1)),which has a moderate defect content.A full cell is assembled using d-HVO-2 as the anode and polyaniline(PANI)as the cathode,which shows excellent cycling stability with a capacity retention rate of 80%after 1000 cycles and outstanding power density up to 4540 W·kg^(-1).Moreover,the flexible d-HVO-2||PANI battery,based on quasi-solid electrolyte,shows excellent flexibility under different bending conditions.This study provides a new approach for designing and developing high-performance NH_(4)^(+)storage electrode materials.

Intermetallic ferric nickel silicide alloy derived from magadiite by magnesiothermic reaction as bifunctional electrocatalyst for overall water splitting

As the cleanest energy source,hydrogen energy is regarded as the most promising fuel.Water electrolysis,as the primary means of hydrogen production,has constantly been the focus of attention in the energy conversion field.Developing eco-friendly,cheap,safe and efficient catalysts for electrochemical water splitting(EWS)is the key challenge.Herein,the intermetallic silicide alloy is first synthesized via a facile magnesiothermic reduction and employed as bifunctional electrocatalysts for EWS.Ferric-nickel silicide(denoted as FeNiSi)alloy is designed and shows a good electrocatalytic performance for EWS.The lattice distortions of FeNiSi enhance the electrocatalytic activity.Besides,the porous structure affords more active sites and improves the reaction kinetics.As a consequence,FeNiSi delivers an excellent performance with overpotential of 308 mV for oxygen evolution reaction(OER)and 386 mV for hydrogen evolution reaction(HER)at 10 mA·cm−2 in 1 M KOH.The stability structure of intermetallic silicide achieves an outstanding durability with an unchanged potential of 1.66 V for overall water splitting at 10 mA·cm−2 for 15 h.This work not only provides a facile method for the synthesis of intermetallic silicide with considerable porous structures,but also develops the potential of intermetallic silicide alloy as bifunctional electrocatalysts for EWS,which opens up a new avenue for the design and application of intermetallic silicide alloy.

Flexible quasi-solid-state zinc-ion hybrid supercapacitor based on carbon cloths displays ultrahigh areal capacitance

Over the past few years,the flexible quasi-solid-state zinc-ion hybrid supercapacitors(FQSS ZHSCs)have been found to be ideal for wearable electronics applications due to their high areal capacitance and energy density.The assembly of desirable ZHSCs devices that have promising practical applications is of high importance,whereas it is still challenging to assemble ZHSCs devices.In this study,a ZHSC that exhibited ultrahigh areal capacitance and high stability was developed by using an active carbon cloth(ACC)cathode,which could improve ionic adsorption.The as-obtained ACC cathode had an energy storage mechanism due to the electrical double-layer capacitive behavior of Zn^(2+),which was accompanied by the dissolution/deposition of Zn_(4)SO_(4)(OH)6·5H2O.The ACC//Zn@ACC ZHSC device exhibited an areal capacitance of 2437 mF cm^(−2)(81 F cm^(−3),203 F g^(-1) under the mass of ACC with∼12 mg cm^(−2))at 1 mA cm^(−2),an areal energy density of 1.354 mWh cm^(−2) at 1 mW cm^(−2),as well as high stability(with an insignificant capacitance decline after 20000 cycles),which was demonstrated to outperform the existing ZHSCs.Furthermore,the assembled flexible device still had competitive capacitance,energy density and service life when integrated into a FQSS ZHSC.When applied in practice,the device could achieve high mechanical flexibility,wearable stability and output.This study can inspire the development of the FQSS ZHSC device to satisfy the demands for wearable energy storage devices with high performance.

Synergistic effect of K^(+)and PANI in vanadium oxide hydration by interlayer engineering boosts the ammonium ion storage

Aqueous ammonium-ion(NH_(4)^(+))hybrid supercapacitor(AA-HSC),as a new type of energy storage device with great potential,is in the initial stage of rapid development.Based on its special energy storage mechanism,exploiting novel NH_(4)^(+)-hostingmaterials is still a great challenge.Herein,vanadium oxide hydration(VOH)tuned by interlayer engineering of K+/PANI co-intercalation,named KVO/PANI,is designed for AA-HSC.Intercalated PANI can shield interaction between NH_(4)^(+)and V–O layers to some extent and enlarge interlayer space,which improves the efficiency of reversible NH_(4)^(+)(de)insertion.However,K+enhances redox activity and electronic conductivity.The synergistic effect of co-intercalation optimizes intercalation pseudocapacitive behavior during the(de)ammonization process,which is reported in NH_(4)^(+)storage for the first time.Theoretical calculations reveal that the lowered electron transport barrier and enhanced electronic conductivity improveNH_(4)^(+)kinetics and exhibit high capacitance for charge storage.The KVO/PANI can deliver the specific capacitance of 340 F g^(−1) at 0.5 A g^(−1) and retain 177 F g^(−1) at 10 A g^(−1).Pairing with activated carbon,the AA-HSC can achieve a decent energy density of 31.8 Wh kg^(−1).This work gives inorganic/organic co-intercalation that can enhance the NH_(4)^(+)storage of VOH by interlayer engineering.The strategy can be used to design other materials for aqueous energy storage systems.

Structural regulation of vanadium oxide by poly(3,4-ethylenedioxithiophene)intercalation for ammonium-ion supercapacitors

Recently,ammonium-ion(NH_(4)^(+))storage is in a booming stage in aqueous energy storage systems due to its multitudinous merits.To seek suitable electrode materials with excellent NH_(4)^(+)-storage is still in the exploratory stage and full of challenge.Herein,an inorganic-polymer hybrid,poly(3,4-ethylenedioxithiophene)(PEDOT)intercalated hydrated vanadium oxide(VOH),named as VOH/PEDOT,is developed to tune the structure of VOH for boosting NH_(4)^(+)storage.By the intercalation of PEDOT,the interlayer space of VOH is increased from 11.5Åto 14.2Å,which notably facilitates the rapid transport of electrons and charges between layers and improves the electrochemical properties for NH_(4)^(+)storage.The achieved performances are much better than progressive NH_(4)^(+)hosting materials.In addition,the concentration of polyvinyl alcohol/ammonium chloride(PVA/NH_(4)Cl)electrolyte exerts a great impact on the NH_(4)^(+)storage in VOH/PEDOT.The VOH/PEDOT electrode delivers specific capacitance of 327 F g^(-1)in 1 M PVA/NH_(4)Cl electrolyte at-0.2–1 V.Furthermore,the quasi-solid-state VOH/PEDOT//active carbon hybrid supercapacitor(QSS VOH/PEDOT//AC HSC)device is assembled for NH_(4)^(+)storage,and it exhibits the capacitance of 328 mF cm^(-2)at 1 mA cm^(-2).The energy density of QSS VOH/PEDOT//AC NH4 t-HSC can reach 2.9 Wh m^(-2)(2.6 mWh cm^(-3),10.4 Wh kg^(-1))at 1 Wm^(-2)(0.9 mWh cm-3,35.7 W kg^(-1)).This work not only proves that the PEDOT intercalation can boost the NH_(4)^(+)storage capacity of vanadium oxides,but also provides a novel direction for the development of NH_(4)^(+)storage materials.

Construction interlayer structure of hydrated vanadium oxides with tunable P-band center of oxygen towards enhanced aqueous Zn-ion batteries

Layered materials with adjustable framework,as the most potential cathode materials for aqueous rechargeable zinc ion batterie,have high capacity,permit of rapid ion diffusion,and charge transfer channels.Previous studies have widely investigated their preparation and storage mechanism,but the intrinsic relationship between the structural design of layered cathode materials and electrochemical performance has not been well established.In this work,based on the first principles calculations and experiments,a crucial strategy of pre-intercalated metalions in vanadium oxide interlayer with administrable p-band center(ε_(p))of O is explored to enhance Zn^(2+)storage.This regulation of the degree of covalent bond and the average charge of O atoms varies the binding energy between Zn^(2+)and O,thus affecting the intercalation/de-intercalation of Zn2þ.The present study demonstrates thatεp of O can be used as an important indicator to boost Zn2þstorage,which provides a new concept toward the controlled design and application of layered materials.

Single‑Atom Catalysts:Advances and Challenges in Metal‑Support Interactions for Enhanced Electrocatalysis

Single-atom catalysts(SACs),which contain a single metal atom supported on a well-confined substrate,are among the most promising heterogeneous catalysts owing to their unique advantages,such as high intrinsic activity and selectivity,tunable bonds and coordination,abundant metal-containing active sites,and atomic economy.Since metal-support interactions(MSIs)in SACs exert a substantial influence on the catalytic properties,gaining a profound understanding and recognition of catalytic reactions depends greatly on investigating MSIs both experimentally and computationally.Hence,the engineer-ing and modulation of MSIs are regarded as one of the most efficient methods to rationally design SACs with disruptively enhanced catalytic properties.In this review,we track the recent advances in SACs from an MSI perspective.We then discuss the existing MSIs in SACs and elucidate the significant role of strong MSIs in catalytic properties and mechanisms.The chal-lenges hindering the rational design of supported SACs with strong MSIs,which are currently still far from being completely understood and overcome,are described.In addition,the correlation between strong MSIs and electrocatalytic activities in SACs,including an outlook to increase our understanding of MSIs,is discussed.Finally,the present review provides some perspectives and an in-depth understanding of strong MSIs to advance high-performing SACs.

PVA-assisted hydrated vanadium pentoxide/reduced graphene oxide films for excellent Li^(+)and Zn^(2+)storage properties

Low-cost,high safety and environment-friendly aqueous energy storage systems(ESSs)are huge potential for grid-level energy storage,but the(de)intercalation of metal ions in the electrode materials(e.g.vanadium oxides)to obtain superior long-term cycling stability is a significant challenge.Herein,we demonstrate that polyvinyl alcohol(PVA)-assisted hydrated vanadium pentoxide/reduced graphene oxide(V_(2)O_(5)·n H_(2)O/r GO/PVA,denoted as the VGP)films enable long cycle stability and high capacity for the Li^(+)and Zn^(2+)storages in both the VGP//Li Cl(aq)//VGP and the VGP//Zn SO4(aq)//Zn cells.The binderfree VGP films are synthesized by a one-step hydrothermal method combination with the filtration.The extensive hydrogen bonds are formed among PVA,GO and H_(2)O,and they act as structural pillars and connect the adjacent layers as glue,which contributes to the ultrahigh specific capacitance and ultralong cyclic performance of Li^(+)and Zn^(2+)storage properties.As for Li^(+)storage,the binder-free VGP4 film(4mg PVA)electrode achieves the highest specific capacitance up to 1381 F g^(-1)at 1.0 A g^(-1)in the three-electrode system and 962 F g^(-1)at 1.0 A g^(-1)in the symmetric two-electrode system.It also behaves the outstanding cyclic performance with the capacitance retention of 96.5%after 15000 cycles in the three-electrode system and 99.7%after 25000 cycles in the symmetric two-electrode system.As for Zn^(2+)storage,the binder-free VGP4 film electrode exhibits the high specific capacity of 184 m A h g^(-1)at 0.5A g^(-1)in the VGP4//Zn SO4(aq)//Zn cell and the superb cycle performance of 98.5%after 25000 cycles.This work not only provides a new strategy for the construction of vanadium oxides composites and demonstrates the potential application of PVA-assisted binder-free film with excellent electrochemical properties,but also extends to construct other potential electrode materials for metal ion storage cells.

Simulated annealing optimization and experiments of a five-bar aerating mechanism for vertically aerating on salt-affected lands

Current agronomic improving treatments for soil salinization are faced with challenges of heavy workload,high cost,etc.,which may seriously restrict agricultural productivity and sustainability on a large scale.Aerator has been applied to loosen soil and enhance soil permeability.In this research,aiming to realize vertically aerating,an aerator with a five-bar aerating mechanism was proposed to improve the aerating performance for saline-alkali land.The five-bar structure of aerating mechanism was designed based on analysis of the aerator on saline-alkali land.The kinematic model was established to describe the aerating process,and the key parameters of the aerating mechanism were obtained by satisfying the motion trajectory conditions.Subsequently,the related parameters were optimized by a simulated annealing method.Furthermore,numerical modeling was simulated to verify the perpendicularity performance after aerating head hitting into the soil.The simulation results indicated that the optimized five-bar aerating mechanism could decrease swinging extreme value by 24%compared with the initial parameters.Finally,the physical prototype of the aerator was tested in the field and performed as expected,producing<7 mm depth tolerances and<3.3°angle tolerances,which met the design requirement.

Effect of mulching with maize straw on water infiltration and soil loss at different initial soil moistures in a rainfall simulation

Mulching and soil water content(SWC) have a significant impact on soil erosion,and this study investigated the effect of straw mulching on water infiltration and soil loss under different initial SWC treatments in a rainfall simulation experiment conducted in northern China.Increasing initial SWC can decrease soil infiltration and increase soil loss.During an 80 mm rainfall event(80 mm·h–1for 60 min),8%,12% and 16% initial SWC treatments decreased cumulative infiltration by8.7%,42.5% and 58.1%,and increased total sediment yield by 44,146 and 315 g,respectively,compared to 4%initial SWC.However,in all the straw mulching treatments,there was no significant difference in stable infiltration rate between the different initial SWC treatments.For all initial SWC treatments,straw mulching of30% or more significantly enhanced water infiltration by over 31% and reduced soil loss by over 49%,compared to the unmulched treatment.Taking into consideration the performance of no-till planters,a maize straw mulching rate of 30% to 60%(1400–3100 kg·hm–2) is recommended for the conservation of water and soil in northern China.