High-throughput calculation-based rational design of Fe-doped MoS_(2) nanosheets for electrocatalytic p H-universal overall water splitting

Electrocatalytic water splitting is crucial for H2generation via hydrogen evolution reaction(HER)but subject to the sluggish dynamics of oxygen evolution reaction(OER).In this work,single Fe atomdoped MoS_(2)nanosheets(SFe-DMNs)were prepared based on the high-throughput density functional theory(DFT)calculation screening.Due to the synergistic effect between Fe atom and MoS_(2)and optimized intermediate binding energy,the SFe-DMNs could deliver outstanding activity for both HER and OER.When assembled into a two-electrode electrolytic cell,the SFe-DMNs could achieve the current density of 50 mA cm^(-2)at a low cell voltage of 1.55 V under neutral condition.These results not only confirmed the effectiveness of high-throughput screening,but also revealed the excellent activity and thus the potential applications in fuel cells of SFe-DMNs.

Tuning the electrochemical behaviors of N-doped LiMn_(x)Fe_(1–x)PO_(4)/C via cation engineering with metal-organic framework-templated strategy

LiFePO_(4),as a prevailing cathode material for lithium-ion batteries(LIBs),still encounters issues such as intrinsic poor electronic conductivity,inferior Li-ion diffusion kinetic,and two-phase transformation mechanism involving substantial structural rearrangements,resulting in unsatisfactory rate performance.Carbon coating,cation doping,and morphological control have been widely employed to reconcile these issues.Inspired by these,we propose a synthetic route with metal–organic frameworks(MOFs)as self-sacrificial templates to simultaneously realize shape modulation,Mn doping,and N-doped carbon coating for enhanced electrochemical performances.The as-synthesized Li MnxFe1–xPO4/C(x=0,0.25,and0.5)deliver tunable electrochemical behaviors induced by the MOF templates,among which LiMn_(0.25)Fe_(0.75)PO_(4)/C outperforms its counterparts in cyclability(164.7 mA h g^(-1)after 200 cycles at 0.5 C)and rate capability(116.3 mA h g^(-1)at 10 C).Meanwhile,the ex-situ XRD reveals a dominant single-phase solid solution mechanism of LiMn_(0.25)Fe_(0.75)PO_(4)/C during delithiation,contrary to the pristine LiFePO_(4),without major structural reconstruction,which helps to explain the superior rate performance.Furthermore,the density functional theory(DFT)calculations verify the effects of Mn doping and embody the superiority of LiMn_(0.25)Fe_(0.75)PO_(4)/C as a LIB cathode,which well supports the experimental observations.This work provides insightful guidance for the design of tunable MOF-derived mixed transitionmetal systems for advanced LIBs.

Rational architecture design of yolk/double-shells Si-based anode material with double buffering carbon layers for high performance lithium-ion battery

Among the many strategies to fabricate the silicon/carbon composite,yolk/double-shells structure can be regarded as an effective strategy to overcome the intrinsic defects of Si-based anode materials for Li-ion batteries(LIBs).Hereon,a facile and inexpensive technology to prepare silicon/carbon composite with yolk/double-shells structure is proposed,in which the double buffering carbon shells are fabricated.The silicon/carbon nanoparticles with core-shell structure are encapsulated by SiO_(2)and external carbon layer,and it shows the yolk/double-shells structure via etching the SiO_(2)sacrificial layer.The multiply shells structure not only significantly improves the electrical conductivity of composite,but also effectively prevents the exposure of Si particles from the electrolyte composition.Meanwhile,the yolk/double-shells structure can provide enough space to accommodate the volume change of the electrode during charge/discharge process and avoid the pulverization of Si particles.Moreover,the as-prepared YDS-Si/C shows excellent performance as anode of LIBs,the reversible capacity is as high as 1066 mA h g^(-1) at the current density of 0.5 A g^(-1) after 200 cycles.At the same time,the YDS-Si/C has high capacity retention and good cyclic stability.Therefore,the unique architecture design of yolk/double-shells for Si/C composite provides an instructive exploration for the development of next generation anode materials of LIBs with high electrochemical performances and structural stability.

Predictive models for characterizing the atomization process in pyrolysis of methyl ricinoleate

Pyrolysis of methyl ricinoleate(MR)can produce undecylenic acid methyl ester and heptanal which are important chemicals.Atomization feeding favors the heat exchange in the pyrolysis process and hence increases the product yield.Herein,predictive models to characterize the atomization process were developed.The effect of spray distance on Sauter mean diameter(SMD)of atomized MR droplets was examined,with the optimal spray distance to be 40-50 mm.Temperature mainly affected the physical properties of feedstock,with smaller droplet size obtained at increasing temperature.In addition,pressure had significant influence on SMD and higher pressure resulted in smaller atomized droplets.Then,a model for SMD prediction,combining temperature,pressure,spray distance,and structural parameters of nozzle,was developed through dimensionless analysis.The results showed that SMD was a power function of Reynolds number(Re),Ohnesorge number(Oh),and the ratio of spray distance to diameter of swirl chamber in the nozzle(H/dsc),with the exponents of-1.6618,-1.3205 and 0.1038,respectively.The experimental measured SMD was in good agreement with the calculated values,with the error within±15%.Moreover,the droplet size distribution was studied by establishing the relationship between the standard deviation of droplet size and SMD.This study could provide reference to the regulation and optimization of the atomization process in MR pyrolysis.

Cooperative catalytic effects between the penta-coordinated Al and Al_(2)O_(3)in Al_(2)O_(3)-AlPO_(4)for aldol condensation of methyl acetate with formaldehyde to methyl acrylate

The bare amorphous Al_(2)O_(3)-AlPO_(4)and Cs/Al_(2)O_(3)-AlPO_(4)catalysts were developed for the aldol condensation of methyl acetate with formaldehyde to methyl acrylate.The structure and property of catalyst were characterized by XRD,XPS,BET,Pyridine-IR,FT-IR,^(27)Al-MASNMR,NH_(3)-/CO_(2)-TPD and SEM.The correlation between structural features and acid-base properties was established,and the loading effect of the cesium species was investigated.Due to cooperative catalytic effects between the penta-coordinated Al and Al_(2)O_(3),the weak-Ⅱacid and medium acid site densities and the product selectivity were improved.While the basic site densities of these catalysts were almost in proportion to the conversion of methyl acetate.The loaded Cs could form new basic sites and change the distribution of acid sites which further enhance the catalytic performance.As a result,the 10Cs/8AlP was proved to be an optimal catalyst with the yield and selectivity of 21.2%and 85%for methyl acrylate respectively.During the reaction,a deactivation behavior was observed on 10Cs/8AlP catalyst due to the carbon deposition,however,it could be regenerated by thermal treatment in the air atmosphere at 400℃.

Insights into biobased epoxidized fatty acid isobutyl esters from biodiesel:Preparation and application as plasticizer

Biodiesel was used to prepare epoxidized fatty acid isobutyl esters(Ep-FABEs)as a biobased plasticizer in this work.Transesterification of biodiesel with isobutanol catalyzed by tetrabutyl titanate was carried out in a gas-liquid tower reactor.The conversion achieved nearly 100%within 5 h under the reaction temperature,the mass ratio of catalyst to fatty acid methyl esters(FAMEs),and isobutanol to FAMEs total molar ratio of 180℃,0.4%(mass),and 5.4:1,respectively.In addition,kinetic model of the transesterification reaction was developed at 150–190℃.The calculated activation energy was 48.93 kJ·mol^(-1).Then,the epoxidation of obtained fatty acid isobutyl esters(FABEs)was conducted in the presence of formic acid and hydrogen peroxide.The Ep-FABEs was further analyzed for its plasticizing effectiveness to replace dioctyl phthalate(DOP)and compared with conventional epoxy plasticizer epoxidized fatty acid methyl esters(Ep-FAMEs).The results indicated that the thermal stability and mechanical properties of PVC films with Ep-FABEs plasticizer were significantly improved compared with those plasticized with DOP.In addition,the extraction resistance and migration stability of Ep-FABEs were better than those of EpFAMEs.Overall,the prepared Ep-FABEs via structural modification of biodiesel proved to be a promising biobased plasticizer.

The accurate localization of fluorescent nanoparticle Au-Ft in nu/nu mice kidney

Au-Ft,as a green synthesized nanoparticle,is composed of a ferritin nanocage enclosing a pair of Au nanoclusters inside.Our previous study has demonstrated that Au-Ft can be an excellentfluorescent probe for whole body imaging of mice with kidney specific targeting.But,the accuratelocalization of Au-Ft in kidney is still absent.In the current study,we detected and assessed the cellular and subcellular localization of Au-Ft in renal cortex and medulla of nu/nu mice after tailvein injection by using Nuance optical system(CRi,Woburn,USA)and inForm intelligent image analysis soft ware based on single cell segmentation.We obtained the fluorescence intensity and cellular location of kidney-targeting Au-Ft probe in particular cell of renal glomerulus or renaltubules,which provided valuable proofs to clarify the mechanism of Au-Ft selective enrichment in kidney and the associated metabolic processes.

Shanghai Gynecologic Oncology Group’s consensus on the academic and industry’s clinical trial types

Shanghai Gynecologic Oncology Group(SGOG,www.ShanghaiGOG.org),[1]established in 2009,is a non-profit organization of clinical research and the full member of Gynecology Cancer Intergroup(GCIG)since 2012.It was guided by Drs.Jinghe Lang(China),Gavin Stuart(Canada)(2009-2020);Drs.Jinghe Lang(China),Ding Ma(China)(2021-)and was supported by Dr.Zeyi Cao(2009-2012).The mission of SGOG is to actively promote the investigator-initiated trial(IIT)in gynecologic cancers,particularly the innovative phase II clinical trials.Followed by the high quality of management in investigators’training,trial development,human resources.

Association between exposure to a mixture of organochlorine pesticides and hyperuricemia in U.S.adults:A comparison of four statistical models

The association between the exposure of organochlorine pesticides(OCPs)and serum uric acid(UA)levels remained uncertain.In this study,to investigate the combined effects of OCP mixtures on hyperuricemia,we analyzed serum OCPs and UA levels in adults from the National Health and Nutrition Examination Survey(2005–2016).Four statistical models including weighted logistic regression,weighted quantile sum(WQS),quantile g-computation(QGC),and bayesian kernel machine regression(BKMR)were used to assess the relationship between mixed chemical exposures and hyperuricemia.Subgroup analyses were conducted to explore potential modifiers.Among 6,529 participants,the prevalence of hyperuricemia was 21.15%.Logistic regression revealed a significant association between both hexachlorobenzene(HCB)and trans-nonachlor and hyperuricemia in the fifth quintile(OR:1.54,95%CI:1.08–2.19;OR:1.58,95%CI:1.05–2.39,respectively),utilizing the first quintile as a reference.WQS and QGC analyses showed significant overall effects of OCPs on hyperuricemia,with an OR of 1.25(95%CI:1.09–1.44)and 1.20(95%CI:1.06–1.37),respectively.BKMR indicated a positive trend between mixed OCPs and hyperuricemia,with HCB having the largest weight in all three mixture analyses.Subgroup analyses revealed that females,individuals aged 50 years and above,and those with a low income were more vulnerable to mixed OCP exposure.These results highlight the urgent need to protect vulnerable populations from OCPs and to properly evaluate the health effects of multiple exposures on hyperuricemia using mutual validation approaches.

A branch-and-price algorithm to perform single-machine scheduling for additive manufacturing

Additive manufacturing(AM)has attracted significant attention in recent years based on its wide range of applications and growing demand.AM offers the advantages of production flexibility and design freedom.In this study,we considered a practical variant of the batch-processing-machine(BPM)scheduling problem that arises in AM industries,where an AM machine can process multiple parts simultaneously,as long as the twodimensional rectangular packing constraint is not violated.Based on the set-partitioning formulation of our mixed-integer programming(MIP)model,a branch-and-price(B&P)algorithm was developed by embedding a column-generation technique into a branchand-bound framework.Additionally,a novel labelling algorithm was developed to accelerate the column-generation process.Ours is the first study to provide a B&P algorithm to solve the BPM scheduling problem in the AM industry.We tested the performance of our algorithm using a modern MIP solver(Gurobi)and real data from a 3D printing factory.The results demonstrate that for most instances tested,our algorithm produces results similar or identical to those of Gurobi with reasonable computation time and outperforms Gurobi in terms of solution quality and running time on some large instances.

In-situ transient photovoltage study on interface electron transfer regulation of carbon dots/NiCo_(2)O_(4) photocatalyst for the enhanced overall water splitting activity

Photocatalytic hydrogen production by overall water solar-splitting is a prospective strategy to solve energy crisis.However,the rapid recombination of photogenerated electron–hole pairs deeply restricts photocatalytic activity of catalysts.Here,the in-situ transient photovoltage(TPV)technique was developed to investigate the interfacial photogenerated carrier extraction,photogenerated carrier recombination and the interfacial electron delivery kinetics of the photocatalyst.The carbon dots/NiCo_(2)O_(4)(CDs/NiCo_(2)O_(4))composite shows weakened recombination rate of photogenerated carriers due to charge storage of CDs,which enhances the photocatalytic water decomposition activity without any scavenger.CDs can accelerate the interface electron extraction about 0.09 ms,while the maximum electron storage time by CDs is up to 0.7 ms.The optimal CDs/NiCo_(2)O_(4)composite(5 wt.%CDs)displays the hydrogen production of 62µmol·h^(−1)·g^(−1) and oxygen production of 29µmol·h^(−1)·g^(−1) at normal atmosphere,which is about 4 times greater than that of pristine NiCo_(2)O_(4).This work provides sufficient evidence on the charge storage of CDs and the interfacial charge kinetics of photocatalysts on the basis of in-situ TPV tests.

High-temperature oxidation behavior of SiBN fibers in air

SiBN fibers are one of the most admirable microwave-transparent reinforced materials for high Mach number aircrafts.Currently,the detailed high-temperature oxidation behavior of SiBN fibers has not been studied yet.In this work,we studied the high-temperature oxidation behavior of SiBN fibers with different boron contents at the temperature range of 1000-1400℃in air.SiBN fibers started to be oxidized at 1100℃,with Si_(3)N_(4) and BN phase oxidized to SiO2 and B_(2)O_(3),respectively.Due to the gasification and the escape of molten B_(2)O_(3) at high temperatures,amorphous SiO_(2) could be remained at the fiber surface.As the fiber further oxidized,the molten B_(2)O_(3) at the inside may infiltrate into the fiber interior to react with Si_(3)N_(4),causing the precipitation of hexagonal boron nitride(h-BN)nanoparticles and the formation of SiO_(2)/BN layer.Finally,complex oxidation layers with two distinct concentric sublayers accompanied with two transition sublayers could be formed after the oxidizing treatment.

Highly dispersed Pt clusters encapsulated in MIL-125-NH_(2) via in situ auto-reduction method for photocatalytic H_(2) production under visible light

Efficient hydrogen production via photocatalysis with high utilization efficiency of Pt cocatalyst is of great importance for sustainable development. In this work, we report an in situ auto-reduction strategy to encapsulate highly dispersed Pt clusters inside the cages of MIL-125-NH_(2). The amino groups in MIL-125-NH_(2) first react with formaldehyde to form reducing groups (i.e.,–NH-CH_(2)OH), which can in situ auto-reduce the confined Pt^(2+) ions to ultrasmall Pt clusters within the cavities. With optimized Pt content, photocatalytic H_(2) production over the obtained Pt(1.5)/MIL-125-NH-CH_(2)OH catalyst with 1.43 wt.% Pt loading achieved as high as 4,496.4 µmol·g^(-1)·h^(-1) under visible light (λ > 420 nm) due to the facilitated transfer and separation of the photo-induced charger carriers arising from the synergetic effects between highly dispersed Pt clusters and MIL-125-NH-CH_(2)OH framework. This in situ auto-reduction strategy may be extended to encapsulate various kinds of metal or alloy clusters/nanoparticles within amino-functioned metal-organic frameworks (MOFs) with superior properties and excellent performance.

Synthesis of graphene oxide nanoribbons/chitosan composite membranes for the removal of uranium from aqueous solutions

In this study,a graphene oxide nanoribbons/chitosan(GONRs/CTS)composite membrane was successfully prepared by encapsulating CTS into GONRs,which were unzipped from multi-walled carbon nanotubes.The GONRs/CTS composite membrane so prepared was characterized using scanning electron microscopy,X-Ray diffraction and Fourier transform infrared spectroscopy.The effects of the experimental conditions such as the pH(2-7),adsorbent dosage(10-50mg),experimental time(5min-32h),uranium concentration(25-300mg·L^-1),experimental temperature(298K-328K)on the adsorption properties of the composite membrane for the removaal of U(VI)were investigated.The results showed that the U(VI)adsorption process of the GONRs/CTS composite membrane was pH-dependent,rapid,spontaneous and endothermic.The adsorption process followed the pseudosecondary kinetics and Langmuir models.The maximum U(VI)adsorption capacity of the GONRs/CTS composite membrane was calculated to be 320mg·g^-1.Hence,the GONRs/CTS composite membrane prepared in this study was found to be suitable for separating and recovering uranium from wastewater.

Characteristics of plankton Hg bioaccumulations based on a global data set and the implications for aquatic systems with aggravating nutrient imbalance

The bioaccumulation of mercury(Hg)in aquatic ecosystem poses a potential health risk to human being and aquatic organism.Bioaccumulations by plankton represent a crucial process of Hg transfer from water to aquatic food chain.However,the current understanding of major factors affecting Hg accumulation by plankton is inadequate.In this study,a data set of 89 aquatic ecosystems worldwide,including inland water,nearshore water and open sea,was established.Key factors influencing plankton Hg bioaccumulation(i.e.,plankton species,cell sizes and biomasses)were discussed.The results indicated that total Hg(THg)and methylmercury(MeHg)concentrations in plankton in inland waters were significantly higher than those in nearshore waters and open seas.Bioaccumulation factors for the logarithm of THg and MeHg of phytoplankton were 2.4–6.0 and 2.6–6.7 L/kg,respectively,in all aquatic ecosystems.They could be further biomagnified by a factor of 2.1–15.1 and 5.3–28.2 from phytoplankton to zooplankton.Higher MeHg concentrations were observed with the increases of cell size for both phyto-and zooplankton.A contrasting trend was observed between the plankton biomasses and BAF_(MeHg),with a positive relationship for zooplankton and a negative relationship for phytoplankton.Plankton physiologic traits impose constraints on the rates of nutrients and contaminants obtaining process from water.Nowadays,many aquatic ecosystems are facing rapid shifts in nutrient compositions.We suggested that these potential influences on the growth and composition of plankton should be incorporated in future aquatic Hg modeling and ecological risk assessments.

超声引导下不同位置收肌管阻滞用于老年全膝关节置换术后的镇痛效果观察

目的探讨超声引导下不同位置收肌管阻滞用于老年患者在全身麻醉下接受单侧全膝关节置换术后的镇痛效果。方法前瞻性收集2019年9月10日至2021年6月30日于秦皇岛市第一医院接受单侧膝关节置换术的老年患者64例,男性34例,女性30例,年龄65~83岁,按照随机数字表法分为两组(n=32),对照组采用超声引导下近端收肌管阻滞,观察组为远端收肌管阻滞。记录两组手术情况包括手术时间,神经阻滞操作时间,术中出血量和术后48 h内引流量,比较两组患者术后疼痛程度、镇痛泵按压和镇痛补救次数、股四头肌肌力以及膝关节活动情况。结果64例患者均获得随访,随访时间10~12个月。两组患者在手术时间、神经阻滞操作时间、术中出血量、术后引流量、术后镇痛药物补救方面差异无统计学意义。两组患者VAS评分和患肢活动情况进行重复测量方差分析,结果显示静息状态下VAS评分不同时间点之间差异有统计学意义(F=29.342,P=0.000)。活动时VAS评分两组间差异有统计学意义(F=12.295,P=0.001),不同时间点之间差异有统计学意义(F=3.373,P=0.010)。术后股四头肌肌力两组患者之间差异有统计学意义(F=6.918,P=0.011),两组术后膝关节活动度有差异(F=7.263,P=0.009),不同时间点差异有统计学意义(F=25.238,P=0.000)。结论远端收肌管阻滞为老年全麻下膝关节置换术后提供较为理想的镇痛效果,对股四头肌肌力影响较小,有利于早期运动功能恢复。

Layered double hydroxide nanosheets activate CsPbBr_(3) nanocrystals for enhanced photocatalytic CO_(2) reduction

Halide perovskite nanocrystals are potential catalysts for CO_(2) photoreduction,while,the strong radiative recombination and insufficient stability limit their catalytic performance and application.Herein,we report that layered double hydroxide nanosheets activate CsPbBr_(3) nanocrystals(CLDH)for enhanced photocatalytic CO_(2) reduction.These CLDH heterojunctions show the remarkably enhanced CO_(2) photoreduction performance;without cocatalyst and sacrificial agent,the average electron consumption rate of CLDH(49.16μmol·g^(−1)·h^(−1))is approximately 3.7 times higher than that of pristine CsPbBr_(3).Also,CLDH catalyst exhibits a robust stability after ten cycles over 30 h.

Covalent-organic frameworks with keto-enol tautomerism for efficient photocatalytic oxidative coupling of amines to imines under visible light

Photocatalytic oxidation of organic molecules into highly value-added products is an innovative and challenging research which has gradually attracted remarkable attention of scientists.In this work,it is demonstrated that the COF-TpPa with keto-enol tautomerism equilibrium structure shows excellent performance(yield>99%after 8 h)in the selective photocatalytic oxidative coupling of amines to imines under visible light irradiation.It is revealed that three kinds of reactive oxygen species(superoxide radical,hydroxyl radical and singlet oxygen)participate in this photocatalytic oxidation reaction.In addition,hydrogen protons cleaved from the benzyl are proven to be reduced to hydrogen in the conduction band of COF-TpPa in anaerobic atmosphere,accompanied with the formation of imines.The direct hydrogen evolution from amine provides an effective way to extract clean energy from organic molecule as well as the production of value-added chemicals.As a contrast,COF-LZU1 with similar structure and chemical composition to COF-TpPa but without keto-enol tautomerism exhibits worse optical properties and photocatalytic performance.It is also demonstrated that keto-enol tautomerism favors the adsorption of benzylamine based on the characterization results and theoretical calculations.

Existence and practice of gaming:thoughts on the development ofmulti-agent system gaming

Game is a universal being in the universe.Starting with human understanding of the game process,we discuss the existence and practice of gaming,expound challenges in multi-agent gaming,and put forward a theoretical framework for a multiagent evolutionary game based on the idea of evolution and system theory.Taking the next-generation early warning and detection system as an example,we introduce the applications of multi-agent evolutionary game.We construct a multi-agent selforganizing game decision-making model and develop a multi-agent method based on reinforcement learning,which are significant in studying organized and systematic game behaviors in a high-dimensional complex environment.

Sensitive and Selective Determination of Cu^(2+) Using Self-Assembly of 4-Mercaptobenzoic Acid on Gold Nanoparticles

Cu^(2+)is a bio-accumulative and toxic environmental pollutant,so its sensitive and selective detection is of great importance.In this work,gold nanoparticles were electrochemically deposited on fluorine-doped tin oxide and characterized by scanning electron microscope and cyclic voltammetry.4-Mercaptobenzoic acid(4-MBA),which contained carboxyl chelator,was self-assembled on the surface of gold nanoparticles through S-Au bond.The strong chelation of Cu^(2+)with 4-MBA formed a stable Cu^(2+)-4-MBA complex,which was confirmed by energy-dispersive X-ray spectroscopy.Square wave voltammetry was applied to determine the concentration of Cu^(2+).Under optimized condition,the oxidation peak current was proportional to the concentration of Cu^(2+)in the range of 10-1500 nM with limit detection of 8 nM.The proposed electrochemical sensor showed excellent selectivity towards Cu^(2+).In addition,the applicability of the developed sensor was evaluated by determin-ing the concentrations of Cu^(2+)in river water samples,which were consistent with the results of inductively coupled plasma mass spectroscopy.