The scratching mechanism of polycrystallineγ-TiAl alloy was investigated at the atomic scale using the molecular dynamics method,with a focus on the influence of different grain sizes.The analysis encompassed tribolo...The scratching mechanism of polycrystallineγ-TiAl alloy was investigated at the atomic scale using the molecular dynamics method,with a focus on the influence of different grain sizes.The analysis encompassed tribological characteristics,scratch morphology,subsurface defect distribution,temperature variations,and stress states during the scratching process.The findings indicate that the scratch force,number of recovered atoms,and pile-up height exhibit abrupt changes when the critical size is 9.41 nm due to the influence of the inverse Hall-Petch effect.Variations in the number of grain boundaries and randomness of grain orientation result in different accumulation patterns on the scratch surface.Notably,single crystal materials and those with 3.73 nm in grain size display more regular surface morphology.Furthermore,smaller grain size leads to an increase in average coefficient of friction,removed atoms number,and wear rate.While it also causes higher temperatures with a larger range of distributions.Due to the barrier effect of grain boundaries,smaller grains exhibit reduced microscopic defects.Additionally,average von Mises stress and hydrostatic compressive stress at the indenter tip decrease as grain size decreases owing to grain boundary obstruction.展开更多
In present work,blue carbon dots(b-CDs)were derived from ammonium citrate and guanidine hydrochloride,and red carbon dots(r-CDs)were stemmed from malonate,ethylenediamine and meso-tetra(4-carboxyphenyl)porphin based o...In present work,blue carbon dots(b-CDs)were derived from ammonium citrate and guanidine hydrochloride,and red carbon dots(r-CDs)were stemmed from malonate,ethylenediamine and meso-tetra(4-carboxyphenyl)porphin based on facile hydrothermal method.Eco-friendly ratiometric fluorescence probe was innovatively constructed to effectively measure Hg2+utilizing b-CDs and r-CDs.The developed probe displayed two typical emission peaks at 450 nm from b-CDs and 650 nm from r-CDs under the excitation at 360 nm.Mercury ion has strong quenching effect on the fluorescence intensity at 450 nm due to the electron transfer process and the fluorescence change at 450 nm was used as the response signal,whereas the fluorescence intensity at 650 nm kept unchangeable which resulted from the chemical inertness between Hg^(2+)and r-CDs,serving as the reference signal in the sensing system.Under optimal circumstances,this probe exhibited an excellent linearity between the fluorescence response values of F450/F650 and Hg^(2+)concentrations over range of 0.01-10μmol/L,and the limit of detectionwas down to 5.3 nmol/L.Furthermore,this probe was successfully employed for sensing Hg^(2+)in practical environmental water samples with satisfied recoveries of 98.5%-105.0%.The constructed ratiometric fluorescent probe provided a rapid,environmental-friendly,reliable,and efficient platform for measuring trace Hg^(2+)in environmental field.展开更多
Liposomes serve as critical carriers for drugs and vaccines,with their biological effects influenced by their size.The microfluidic method,renowned for its precise control,reproducibility,and scalability,has been wide...Liposomes serve as critical carriers for drugs and vaccines,with their biological effects influenced by their size.The microfluidic method,renowned for its precise control,reproducibility,and scalability,has been widely employed for liposome preparation.Although some studies have explored factors affecting liposomal size in microfluidic processes,most focus on small-sized liposomes,predominantly through experimental data analysis.However,the production of larger liposomes,which are equally significant,remains underexplored.In this work,we thoroughly investigate multiple variables influencing liposome size during microfluidic preparation and develop a machine learning(ML)model capable of accurately predicting liposomal size.Experimental validation was conducted using a staggered herringbone micromixer(SHM)chip.Our findings reveal that most investigated variables significantly influence liposomal size,often interrelating in complex ways.We evaluated the predictive performance of several widely-used ML algorithms,including ensemble methods,through cross-validation(CV)for both lipo-some size and polydispersity index(PDI).A standalone dataset was experimentally validated to assess the accuracy of the ML predictions,with results indicating that ensemble algorithms provided the most reliable predictions.Specifically,gradient boosting was selected for size prediction,while random forest was employed for PDI prediction.We successfully produced uniform large(600 nm)and small(100 nm)liposomes using the optimised experimental conditions derived from the ML models.In conclusion,this study presents a robust methodology that enables precise control over liposome size distribution,of-fering valuable insights for medicinal research applications.展开更多
It is well known that coarse-grained super-elastic NiTi shape memory alloys(SMAs)exhibit localized rather than homogeneous martensite transformation(MT),which,however,can be strongly influenced by either internal size...It is well known that coarse-grained super-elastic NiTi shape memory alloys(SMAs)exhibit localized rather than homogeneous martensite transformation(MT),which,however,can be strongly influenced by either internal size(grain size,GS)or the external size(geometric size).The coupled effect of GS and geometric size on the functional properties has not been clearly understood yet.In this work,the super-elasticity,one-way,and stress-assisted two-way shape memory effects of the polycrystalline NiTi SMAs with different aspect ratios(length/width for the gauge section)and different GSs are investigated based on the phase field method.The coupled effect of the aspect ratio and GS on the functional properties is adequately revealed.The simulated results indicate that when the aspect ratio is lower than about 4:1,the stress biaxiality and stress heterogeneity in the gauge section of the sample become more and more obvious with decreasing the aspect ratio,which can significantly influence the microstructure evolution in the process involving external stress.Therefore,the corresponding functional property is strongly dependent on the aspect ratio.With decreasing the GS and the aspect ratio(to be lower than 4:1),both the aspect ratio and GS can affect the MT or martensite reorientation in each grain and the interaction among grains.Thus,due to the strong internal constraint(i.e.,the constraint of grain boundary)and the external constraint(i.e.,the constraint of geometric boundary),the capabilities of the functional properties of NiTi SMAs are gradually weakened and highly dependent on these two factors.展开更多
A new analytical model for geometric size and forming force prediction in incremental flanging(IF)is presented in this work.The complex deformation characteristics of IF are considered in the modeling process,which ca...A new analytical model for geometric size and forming force prediction in incremental flanging(IF)is presented in this work.The complex deformation characteristics of IF are considered in the modeling process,which can accurately describe the strain and stress states in IF.Based on strain analysis,the model can predict the material thickness distribution and neck height after IF.By considering contact area,strain characteristics,material thickness changes,and friction,the model can predict specific moments and corresponding values of maximum axial forming force and maximum horizontal forming force during IF.In addition,an IF experiment involving different tool diameters,flanging diameters,and opening hole diameters is conducted.On the basis of the experimental strain paths,the strain characteristics of different deformation zones are studied,and the stable strain ratio is quantitatively described through two dimensionless parameters:relative tool diameter and relative hole diameter.Then,the changing of material thickness and forming force in IF,and the variation of minimum material thickness,neck height,maximum axial forming force,and maximum horizontal forming force with flanging parameters are studied,and the reliability of the analytical model is verified in this process.Finally,the influence of the horizontal forming force on the tool design and the fluctuation of the forming force are explained.展开更多
Large size titanium alloy parts are widely used in aerospace.However,they are difficult to manufacture using mechanical cutting technology because of severe tool wear.Electrochemical jet machining is a promising techn...Large size titanium alloy parts are widely used in aerospace.However,they are difficult to manufacture using mechanical cutting technology because of severe tool wear.Electrochemical jet machining is a promising technology to achieve high efficiency,because it has high machining flexibility and no machining tool wear.However,reports on the macro electrochemical jet machining of large size titanium alloy parts are very scarce,because it is difficult to achieve effective constraint of the flow field in macro electrochemical jet machining.In addition,titanium alloy is very sensitive to fluctuation of the flow field,and a turbulent flow field would lead to serious stray corrosion.This paper reports a series of investigations of the electrochemical jet machining of titanium alloy parts.Based on the flow analysis and experiments,the machining flow field was effectively constrained.TB6 titanium alloy part with a perimeter of one meter was machined.The machined surface was smooth with no obvious machining defects.The machining process was particularly stable with no obvious spark discharge.The research provides a reference for the application of electrochemical jet machining technology to achieve large allowance material removal in the machining of large titanium alloy parts.展开更多
The influence of graphene platelets(GPLs)on the WC grain size of WC-Co-GPLs cemented carbide prepared by low-pressure sintering was investigated.The role of GPLs in refining WC grains was explored by characterizing gr...The influence of graphene platelets(GPLs)on the WC grain size of WC-Co-GPLs cemented carbide prepared by low-pressure sintering was investigated.The role of GPLs in refining WC grains was explored by characterizing grain size and phase distribution.Results show that the addition of GPLs leads to significant grain refinement of WC and the more uniform distribution of WC grain size.When the content of GPLs is 0.10wt%,the average WC grain size in the cemented carbide is 0.39μm,which is 32%lower than that in WC-Co.However,the shape of WC grains is almost unaffected,while the mean free path of Co decreases.The grain refinement of WC is attributed to the homogeneous distribution of GPLs between WC/WC and WC/Co grain boundaries,which hinders the solution and precipitation process of WC in liquid phase Co,as well as the migration and growth of WC grains.Additionally,GPLs can serve as heat transfer plates in materials to improve cooling efficiency,thus inhibiting the growth of WC grain.展开更多
The mechanical behavior of cemented gangue backfill materials(CGBMs)is closely related to particle size distribution(PSD)of aggregates and properties of cementitious materials.Consequently,the true triaxial compressio...The mechanical behavior of cemented gangue backfill materials(CGBMs)is closely related to particle size distribution(PSD)of aggregates and properties of cementitious materials.Consequently,the true triaxial compression tests,CT scanning,SEM,and EDS tests were conducted on cemented gangue backfill samples(CGBSs)with various carbon nanotube concentrations(P_(CNT))that satisfied fractal theory for the PSD of aggregates.The mechanical properties,energy dissipations,and failure mechanisms of the CGBSs under true triaxial compression were systematically analyzed.The results indicate that appropriate carbon nanotubes(CNTs)effectively enhance the mechanical properties and energy dissipations of CGBSs through micropore filling and microcrack bridging,and the optimal effect appears at P_(CNT)of 0.08wt%.Taking PSD fractal dimension(D)of 2.500 as an example,compared to that of CGBS without CNT,the peak strength(σ_(p)),axial peak strain(ε_(1,p)),elastic strain energy(Ue),and dissipated energy(U_(d))increased by 12.76%,29.60%,19.05%,and90.39%,respectively.However,excessive CNTs can reduce the mechanical properties of CGBSs due to CNT agglomeration,manifesting a decrease inρ_(p),ε_(1,p),and the volumetric strain increment(Δε_(v))when P_(CNT)increases from 0.08wt%to 0.12wt%.Moreover,the addition of CNTs improved the integrity of CGBS after macroscopic failure,and crack extension in CGBSs appeared in two modes:detour and pass through the aggregates.Theσ_(p)and U_(d)firstly increase and then decrease with increasing D,and porosity shows the opposite trend.Theε_(1,p)andΔε_(v)are negatively correlated with D,and CGBS with D=2.150 has the maximum deformation parameters(ε_(1,p)=0.05079,Δε_(v)=0.01990)due to the frictional slip effect caused by coarse aggregates.With increasing D,the failure modes of CGBSs are sequentially manifested as oblique shear failure,"Y-shaped"shear failure,and conjugate shear failure.展开更多
A gold catalyst of Au/pyrenyl‑graphdiyne(Pyr‑GDY)was prepared by anchoring small size of gold nanoparticles(Au NPs)on the surface of Pyr‑GDY for electrocatalytic nitrogen reduction reaction(eNRR),in which Au NPs with ...A gold catalyst of Au/pyrenyl‑graphdiyne(Pyr‑GDY)was prepared by anchoring small size of gold nanoparticles(Au NPs)on the surface of Pyr‑GDY for electrocatalytic nitrogen reduction reaction(eNRR),in which Au NPs with a size of approximately 3.69 nm was evenly distributed on spongy‑like porous Pyr‑GDY.The catalyst exhibited a good electrocatalytic activity for N_(2)reduction in a nitrogen‑saturated electrolyte,with an ammonia yield of 32.1μg·h^(-1)·mg_(cat)^(-1)at-0.3 V(vs RHE),3.5 times higher than that of Au/C(Au NPs anchored on carbon black).In addition,Au/Pyr‑GDY showed a Faraday efficiency(FE)of 26.9%for eNRR,and a good catalysis durability for over 22 h.展开更多
The extraordinary strength of metal/graphene composites is significantly determined by the characteristic size,distribution and morphology of graphene.However,the effect of the graphene size/distribution on the mechan...The extraordinary strength of metal/graphene composites is significantly determined by the characteristic size,distribution and morphology of graphene.However,the effect of the graphene size/distribution on the mechanical properties and related strengthening mechanisms has not been fully elucidated.Herein,under the same volume fraction and distribution conditions of graphene,molecular dynamics simulations were used to investigate the effect of graphene sheet size on the hardness and deformation behavior of Cu/graphene composites under complex stress field.Two models of pure single crystalline Cu and graphene fully covered Cu matrix composite were constructed for comparison.The results show that the strengthening effect changes with varying the graphene sheet size.Besides the graphene dislocation blocking effect and the load-bearing effect,the deformation mechanisms change from stacking fault tetrahedron,dislocation bypassing and dislocation cutting to dislocation nucleation in turn with decreasing the graphene sheet size.The hardness of Cu/graphene composite,with the graphene sheet not completely covering the metal matrix,can even be higher than that of the fully covered composite.The extra strengthening mechanisms of dislocation bypassing mechanism and the stacking fault tetrahedra pinning dislocation mechanism contribute to the increase in hardness.展开更多
All maritime industries are plagued by marine biofouling pollution,which causes large economic and environmental costs.Therefore,there is an urgent need for ecofriendly alternatives that can effectively reduce the neg...All maritime industries are plagued by marine biofouling pollution,which causes large economic and environmental costs.Therefore,there is an urgent need for ecofriendly alternatives that can effectively reduce the negative consequences of biofouling pollution.This study aimed to produce novel capsaicin-inspired amide derivatives(CIADs)with multifunctional antifouling features by introducing amide compounds to aromatic compounds via a Friedel-Crafts alkylation reaction.The structure of the CIADs was characterized using FTIR,1H NMR,13C NMR,and HRMS,and the comprehensive antifouling capacity was determined by thermal stability,anti-ultraviolet,antibacterial,anti-algal,and marine field experiments.CIADs showed good thermal stability and did not show obvious weight loss before 226°C.2,4-dihydroxy-3,5-diphenylimidemet-hylbenzophenone(DDB)had an excellent ultraviolet absorption effect,which was even better than that of 2-hydroxy-4-(octyloxy)benzophenone.The antibacterial and anti-algal rates of N-(2,4-dimethyl-3-chloro-5-benzamide-methyl-6-hydroxybenzyl)benzamide(NDCBHB)were more than 99.5%and 64.0%,respectively,and the surface of antifouling coating with NDCBHB(NDCBHB-AC)was covered with only a small amount of sludge and biofilm,its antifouling effect was better than that of chlorothalonil.The above work provides a reference for preparing green and multifunctional antifouling agents.展开更多
Eco-friendly quantum-dot light-emitting diodes(QLEDs),which employ colloidal quantum dots(QDs)such as InP,and ZnSe,stand out due to their low toxicity,color purity,and high efficiency.Currently,significant advancement...Eco-friendly quantum-dot light-emitting diodes(QLEDs),which employ colloidal quantum dots(QDs)such as InP,and ZnSe,stand out due to their low toxicity,color purity,and high efficiency.Currently,significant advancements have been made in the performance of cadmium-free QLEDs.However,several challenges persist in the industrialization of ecofriendly QLED displays.For instance,(1)the poor performance,characterized by low photoluminescence quantum yield(PLQY),unstable ligand,and charge imbalance,cannot be effectively addressed with a solitary strategy;(2)the degradation mechanism,involving emission quenching,morphological inhomogeneity,and field-enhanced electron delocalization remains unclear;(3)the lack of techniques for color patterning,such as optical lithography and transfer printing.Herein,we undertake a specific review of all technological breakthroughs that endeavor to tackle the above challenges associated with cadmium-free QLED displays.We begin by reviewing the evolution,architecture,and operational characteristics of eco-friendly QLEDs,highlighting the photoelectric properties of QDs,carrier transport layer stability,and device lifetime.Subsequently,we focus our attention not only on the latest insights into device degradation mechanisms,particularly,but also on the remarkable technological progress in color patterning techniques.To conclude,we provide a synthesis of the promising prospects,current challenges,potential solutions,and emerging research trends for QLED displays.展开更多
Constructed Wetlands (CWs) are currently one of the most promising techniques for wastewater treatment, having demonstrated their effectiveness. However, the choice of substrate particle size is critical to the smooth...Constructed Wetlands (CWs) are currently one of the most promising techniques for wastewater treatment, having demonstrated their effectiveness. However, the choice of substrate particle size is critical to the smooth operation of the process, as hydrodynamic constraints require a coarse particle size, whereas wastewater treatment recommends a fine particle size. This study investigates the suitability of laterite and shale as substrates of different sizes (1 - 3, 3 - 5 and 5 - 8 mm) in CWs for domestic wastewater treatment. The study was carried out in an experimental pilot plant consisting of 12 parallelepiped beds (C × C = 0.4 × 0.4 m2;H = 0.6 m) filled from bottom to top with 0.1 m of gravel and 0.4 m of shale or laterite of different grain sizes with two replications. During the six months of operation, plant biomass and stem diameter of Pennisetum purpureum used as vegetation in the CWs were determined. Raw and treated water were also sampled and analyzed for pollutants, including chemical oxygen demand (COD), biochemical oxygen demand (BOD5), total Kjedahl nitrogen (TKN), total phosphorus (TP), and total suspended solids (TSS), using International Organization for Standardization (ISO) analytical methods. P. purpureum developed much better in the CW beds lined with shale;plant biomass ranged from 13.8 to 14.7 kg/m2 and from 11.2 to 12.5 kg/m2 in the beds lined with shale and laterite, respectively, as did stump diameter, which ranged from 15.5 to 16.1 cm and from 11.10 to 12.7 cm, respectively. However, the highest values for biomass and stump diameter for each material were obtained in the beds lined with 1 - 3 mm geomaterials. Pollutant removal efficiencies were highest in the CWs lined with laterite and shale of 1 - 3 mm grain size (76.9% - 83% COD, 78% - 84.7% BOD5, 55.5% - 72.2% TKN, 58.4% - 72.4% TP, 78.1% - 80.2% TSS), with the highest values recorded in the shale-lined beds. However, the 3 - 5 mm grain size of both materials provided quality filtrates (140 - 174 mg/L COD, 78.5 - 94.8 mg/L BOD5, 4.6 - 5.7 mg/L TP) in line with local wastewater discharge levels. This size of geomaterials appears to be suitable for optimization purposes, although further work with these materials, such as increasing the depth of the wetland, is required to improve the level of NTK and TSS discharge.展开更多
The global reliance on phosphate rock for agriculture and other industries,coupled with chemical regulations in developed countries,has driven the search for green alternatives in apatite flotation.This review investi...The global reliance on phosphate rock for agriculture and other industries,coupled with chemical regulations in developed countries,has driven the search for green alternatives in apatite flotation.This review investigates eco-friendly collectors’effectiveness in promoting sustainable mineral processing,guiding future alternatives to traditional reagents.The manuscript discussed the surface properties of apatite and its interaction with eco-friendly collectors,assessing existing fundamental studies.This study sought to:(1)define,organize,and classify“eco-friendly”collectors;(2)evaluate their effect in IEP and contact angle;(3)provide a better understanding of the adsorption behavior of the different fatty acid chains into apatite surface;(4)assess their ability to reversely and directly float apatite;(5)address gaps to achieve selectivity and process optimization.Outcomes demonstrated that fatty acids are largely applied,but other renewable sources of these reagents have been promisingly evaluated.In addition,other natural reagents have been tested,and new green synthetics have demonstrated synergistic effects when combined with fatty acids,yielding significant improvements in grade and recovery.However,collector effectiveness varies with ore characteristics,like particle size and surface properties,which remain underexplored.Future research should design tailored collectors that align with mineralogical differences to enhance selectivity.展开更多
Nowadays,the development of effective bioplastics aims to combine traditional plastics’functionality with environmentally friendly properties.The most effective and durable modern bioplastics are made from the edible...Nowadays,the development of effective bioplastics aims to combine traditional plastics’functionality with environmentally friendly properties.The most effective and durable modern bioplastics are made from the edible part of crops.This forces bioplastics to competewith food production because the crops that produce bioplastics can also be used for human nutrition.That is why the article’s main focus is on creating bioplastics using renewable,non-food raw materials(cellulose,lignin,etc.).Eco-friendly composites based on a renewable bioplastic blend of polybutylene adipate-co-terephthalate,corn starch,and poly(lactic acid)with reed and hemp waste as a filler.The physic-chemical features of the structure and surface,as well as the technological characteristics of reed and hemp waste as the organic fillers for renewable bioplastic blend of polybutylene adipate-co-terephthalate,corn starch,and poly(lactic acid),were studied.Theeffect of the fractional composition analysis,morphology,and nature of reed and hempwaste on the quality of the design of eco-friendly biodegradable composites and their ability to disperse in the matrix of renewable bioplastic blend of polybutylene adipate-co-terephthalate,corn starch and poly(lactic acid)was carried out.The influence of different content and morphology of reed and hemp waste on the composite characteristics was investigated.It is shown that the most optimal direction for obtaining strong eco-friendly biodegradable composites based on a renewable bioplastic blend of polybutylene adipate-co-terephthalate,corn starch,and poly(lactic acid)is associated with the use of waste reed stalks,with its optimal content at the level of 50 wt.%.展开更多
Even the sulfur cathode in lithium-sulfur(Li-S)battery has the advantages of high theoretical energy density,wide source of raw materials,no pollution to the environment,and so on.It still suffers the sore points of e...Even the sulfur cathode in lithium-sulfur(Li-S)battery has the advantages of high theoretical energy density,wide source of raw materials,no pollution to the environment,and so on.It still suffers the sore points of easy electrode collapse due to large volume expansion during charge and discharge and low active materials utilization caused by the severe shuttle effect of lithium polysulfides(LiPSs).Therefore,in this work,ramie gum(RG)was extracted from ramie fiber degumming liquid and used as the functional binder to address the above problems and improve the Li-S battery’s performance for the first time.Surprisingly,the sulfur cathode using RG binder illustrates a high initial capacity of 1152.2 mAh/g,and a reversible capacity of 644.6 mAh/g after 500 cycles at 0.5 C,far better than the sulfur cathode using polyvinylidene fluoride(PVDF)and sodium carboxymethyl cellulose(CMC)binder.More importantly,even if the active materials loading increased to as high as 4.30 mg/cm^(2),the area capacity is still around 3.1 mAh/cm^(2)after 200 cycles.Such excellent performances could be attributed to the abundant oxygen-and nitrogen-containing functional groups of RG that can effectively inhibit the shuttle effect of LiPSs,as well as the excellent viscosity and mechanical properties that can maintain electrode integrity during long-term charging/discharging.This work verifies the feasibility of RG as an eco-friendly and high-performance Li-S battery binder and provides a new idea for the utilization of agricultural biomass resources.展开更多
This study evaluates the performance of advanced machine learning(ML)models in predicting the mechanical properties of eco-friendly self-compacting concrete(SCC),with a focus on compressive strength,V-funnel time,Lbox...This study evaluates the performance of advanced machine learning(ML)models in predicting the mechanical properties of eco-friendly self-compacting concrete(SCC),with a focus on compressive strength,V-funnel time,Lbox ratio,and slump flow.The motivation for this study stems from the increasing need to optimize concrete mix designs while minimizing environmental impact and reducing the reliance on costly physical testing.Six ML models-backpropagation neural network(BPNN),random forest regression(RFR),K-nearest neighbors(KNN),stacking,bagging,and eXtreme gradient boosting(XGBoost)-were trained and validated using a comprehensive dataset of 239 mix design parameters.The models'predictive accuracies were assessed using the coefficient of determination,mean squared error,root mean squared error,and mean absolute error.XGBoost consistently outperformed other models,achieving the coefficient of determination values of 0.999,0.933,and 0.935 for compressive strength in the training,validation,and testing datasets,respectively.Sensitivity analysis revealed that cement,silica fume,coarse aggregate,and superplasticizer positively influenced compressive strength,while water content had a negative impact.These findings highlight the potential of ML models,particularly XGBoost and RFR,in optimizing SCC mix designs,reducing reliance on physical testing,and enhancing sustainability in construction.The application of these models can lead to more efficient and eco-friendly concrete mix designs,benefiting real-world construction projects by improving quality control and reducing costs.展开更多
Kitaev quantum spin liquids have attracted significant attention in condensed matter physics over the past decade.To understand their emergent quantum phenomena,high-quality single crystals of substantial size are ess...Kitaev quantum spin liquids have attracted significant attention in condensed matter physics over the past decade.To understand their emergent quantum phenomena,high-quality single crystals of substantial size are essential.Here,we report the synthesis of single crystals of the Kitaev quantum spin liquid candidate RuBr_(3),achieving millimeter-sized crystals through a self-flux method under high pressure and high temperature conditions.The crystals exhibit well-defined cleavage planes with a lustrous appearance.Transport characterizations exhibit a narrow band-gap semiconducting behavior with 0.13 eV and 0.11 eV band-gap in ab plane and along𝑐axis,respectively.Magnetic measurement shows a transition to antiferromagnetic(AFM)state at approximately 29K both in ab plane and along the c axis.Notably,the N′eel temperature increases to 34K with an applied magnetic field of up to 7T in the ab plane,but without any change along𝑐axis.The large size and high quality of RuBr3 single crystals provide a valuable platform for investigating various interactions,particularly the Kitaev interaction,and for elucidating the intrinsic physical properties of Kitaev quantum spin liquids.展开更多
To the Editor:Thymic carcinoma is a highly aggressive subtype of thymomas,accounting for 1%of thymic malignancies.It predominantly(80%)manifests in the anterosuperior mediastinum[1].Nevertheless,the occurrence of extr...To the Editor:Thymic carcinoma is a highly aggressive subtype of thymomas,accounting for 1%of thymic malignancies.It predominantly(80%)manifests in the anterosuperior mediastinum[1].Nevertheless,the occurrence of extrathoracic metastases,particularly liver metastases,is uncommon.The clinical manifestation of thymic carcinoma accompanied by liver metastases is characterized by ambiguous and nonspecific symptoms.Consequently,it is challenging to ascertain.展开更多
This study investigates the size characteristics and related temporal variations of tropical cyclones(TCs)over the Western North Pacific(WNP)and those affecting East China(EC)using Joint Typhoon Warning Center(JTWC)da...This study investigates the size characteristics and related temporal variations of tropical cyclones(TCs)over the Western North Pacific(WNP)and those affecting East China(EC)using Joint Typhoon Warning Center(JTWC)data during 2001-20.The average size of EC TCs is found to be similar to that over the WNP.Furthermore,the annual maximum lifetime maximum size(LMS)of EC TCs shows a statistically significant increasing trend,implying a more severe impact on the EC region.Composite analyses of intensity and size variation over the entire lifetime of TCs,before and after re-curvature,and before and after rapid intensification(RI),show that there are significant differences between them in some key areas:(1)The intensity begins to rapidly decrease after the TC has reached its highest intensity,but the size remains quasi-constant;(2)When a TC recurves south of 15°N or north of 30°N,the variation trend for both intensity and size are broadly similar before and after curvature,but their variation trends are opposite when the recurvature occurs between 15°-30°N;(3)After RI,the intensity reaches its peak value within 24 h,whereas the size reaches its LMS after30-48 h.A significant correlation is also found between the rate of change in intensity and that of size during the development stage,with a correlation coefficient of 0.67 and 0.73 for TCs in the WNP and EC,respectively.However,no significant correlation exists during the weakening stage.展开更多
基金National Natural Science Foundation of China(52065036,52365018)Natural Science Foundation of Gansu(23JRRA760)+1 种基金Hongliu Outstanding Youth Foundation of Lanzhou University of TechnologyChina Postdoctoral Science Foundation(2023M733583)。
文摘The scratching mechanism of polycrystallineγ-TiAl alloy was investigated at the atomic scale using the molecular dynamics method,with a focus on the influence of different grain sizes.The analysis encompassed tribological characteristics,scratch morphology,subsurface defect distribution,temperature variations,and stress states during the scratching process.The findings indicate that the scratch force,number of recovered atoms,and pile-up height exhibit abrupt changes when the critical size is 9.41 nm due to the influence of the inverse Hall-Petch effect.Variations in the number of grain boundaries and randomness of grain orientation result in different accumulation patterns on the scratch surface.Notably,single crystal materials and those with 3.73 nm in grain size display more regular surface morphology.Furthermore,smaller grain size leads to an increase in average coefficient of friction,removed atoms number,and wear rate.While it also causes higher temperatures with a larger range of distributions.Due to the barrier effect of grain boundaries,smaller grains exhibit reduced microscopic defects.Additionally,average von Mises stress and hydrostatic compressive stress at the indenter tip decrease as grain size decreases owing to grain boundary obstruction.
基金supported by the National Natural Science Foundation of China (Nos.22106039,21976211,and 42007204)the Science Foundation of Henan Normal University (No.2021PL23)+1 种基金the Excellent Science and Technology Innovation Team of Henan Normal University (No.2021TD06)the Program for Innovative Research Team in Science and Technology in the University of Henan Province (No.20IRTSTHN011).
文摘In present work,blue carbon dots(b-CDs)were derived from ammonium citrate and guanidine hydrochloride,and red carbon dots(r-CDs)were stemmed from malonate,ethylenediamine and meso-tetra(4-carboxyphenyl)porphin based on facile hydrothermal method.Eco-friendly ratiometric fluorescence probe was innovatively constructed to effectively measure Hg2+utilizing b-CDs and r-CDs.The developed probe displayed two typical emission peaks at 450 nm from b-CDs and 650 nm from r-CDs under the excitation at 360 nm.Mercury ion has strong quenching effect on the fluorescence intensity at 450 nm due to the electron transfer process and the fluorescence change at 450 nm was used as the response signal,whereas the fluorescence intensity at 650 nm kept unchangeable which resulted from the chemical inertness between Hg^(2+)and r-CDs,serving as the reference signal in the sensing system.Under optimal circumstances,this probe exhibited an excellent linearity between the fluorescence response values of F450/F650 and Hg^(2+)concentrations over range of 0.01-10μmol/L,and the limit of detectionwas down to 5.3 nmol/L.Furthermore,this probe was successfully employed for sensing Hg^(2+)in practical environmental water samples with satisfied recoveries of 98.5%-105.0%.The constructed ratiometric fluorescent probe provided a rapid,environmental-friendly,reliable,and efficient platform for measuring trace Hg^(2+)in environmental field.
基金supported by the National Key Research and Development Plan of the Ministry of Science and Technology,China(Grant No.:2022YFE0125300)the National Natural Science Foundation of China(Grant No:81690262)+2 种基金the National Science and Technology Major Project,China(Grant No.:2017ZX09201004-021)the Open Project of National facility for Translational Medicine(Shanghai),China(Grant No.:TMSK-2021-104)Shanghai Jiao Tong University STAR Grant,China(Grant Nos.:YG2022ZD024 and YG2022QN111).
文摘Liposomes serve as critical carriers for drugs and vaccines,with their biological effects influenced by their size.The microfluidic method,renowned for its precise control,reproducibility,and scalability,has been widely employed for liposome preparation.Although some studies have explored factors affecting liposomal size in microfluidic processes,most focus on small-sized liposomes,predominantly through experimental data analysis.However,the production of larger liposomes,which are equally significant,remains underexplored.In this work,we thoroughly investigate multiple variables influencing liposome size during microfluidic preparation and develop a machine learning(ML)model capable of accurately predicting liposomal size.Experimental validation was conducted using a staggered herringbone micromixer(SHM)chip.Our findings reveal that most investigated variables significantly influence liposomal size,often interrelating in complex ways.We evaluated the predictive performance of several widely-used ML algorithms,including ensemble methods,through cross-validation(CV)for both lipo-some size and polydispersity index(PDI).A standalone dataset was experimentally validated to assess the accuracy of the ML predictions,with results indicating that ensemble algorithms provided the most reliable predictions.Specifically,gradient boosting was selected for size prediction,while random forest was employed for PDI prediction.We successfully produced uniform large(600 nm)and small(100 nm)liposomes using the optimised experimental conditions derived from the ML models.In conclusion,this study presents a robust methodology that enables precise control over liposome size distribution,of-fering valuable insights for medicinal research applications.
基金supported by the National Natural Science Foundation of China (Grant Nos.12202294 and 12022208)the Project funded by China Postdoctoral Science Foundation (Grant No.2022M712243)the Fundamental Research Funds for the Central Universities (Grant No.2023SCU12098).
文摘It is well known that coarse-grained super-elastic NiTi shape memory alloys(SMAs)exhibit localized rather than homogeneous martensite transformation(MT),which,however,can be strongly influenced by either internal size(grain size,GS)or the external size(geometric size).The coupled effect of GS and geometric size on the functional properties has not been clearly understood yet.In this work,the super-elasticity,one-way,and stress-assisted two-way shape memory effects of the polycrystalline NiTi SMAs with different aspect ratios(length/width for the gauge section)and different GSs are investigated based on the phase field method.The coupled effect of the aspect ratio and GS on the functional properties is adequately revealed.The simulated results indicate that when the aspect ratio is lower than about 4:1,the stress biaxiality and stress heterogeneity in the gauge section of the sample become more and more obvious with decreasing the aspect ratio,which can significantly influence the microstructure evolution in the process involving external stress.Therefore,the corresponding functional property is strongly dependent on the aspect ratio.With decreasing the GS and the aspect ratio(to be lower than 4:1),both the aspect ratio and GS can affect the MT or martensite reorientation in each grain and the interaction among grains.Thus,due to the strong internal constraint(i.e.,the constraint of grain boundary)and the external constraint(i.e.,the constraint of geometric boundary),the capabilities of the functional properties of NiTi SMAs are gradually weakened and highly dependent on these two factors.
基金supported in part by financial support from the National Key R&D Program of China(No.2023YFB3407003)the National Natural Science Foundation of China(No.52375378).
文摘A new analytical model for geometric size and forming force prediction in incremental flanging(IF)is presented in this work.The complex deformation characteristics of IF are considered in the modeling process,which can accurately describe the strain and stress states in IF.Based on strain analysis,the model can predict the material thickness distribution and neck height after IF.By considering contact area,strain characteristics,material thickness changes,and friction,the model can predict specific moments and corresponding values of maximum axial forming force and maximum horizontal forming force during IF.In addition,an IF experiment involving different tool diameters,flanging diameters,and opening hole diameters is conducted.On the basis of the experimental strain paths,the strain characteristics of different deformation zones are studied,and the stable strain ratio is quantitatively described through two dimensionless parameters:relative tool diameter and relative hole diameter.Then,the changing of material thickness and forming force in IF,and the variation of minimum material thickness,neck height,maximum axial forming force,and maximum horizontal forming force with flanging parameters are studied,and the reliability of the analytical model is verified in this process.Finally,the influence of the horizontal forming force on the tool design and the fluctuation of the forming force are explained.
基金the National Natural Science Foundation of China(No.52205468)China Postdoctoral Science Foundation(No.2022M710061 and No.2023T160277)Natural Science Foundation of Jiangsu Province(No.BK20210755)。
文摘Large size titanium alloy parts are widely used in aerospace.However,they are difficult to manufacture using mechanical cutting technology because of severe tool wear.Electrochemical jet machining is a promising technology to achieve high efficiency,because it has high machining flexibility and no machining tool wear.However,reports on the macro electrochemical jet machining of large size titanium alloy parts are very scarce,because it is difficult to achieve effective constraint of the flow field in macro electrochemical jet machining.In addition,titanium alloy is very sensitive to fluctuation of the flow field,and a turbulent flow field would lead to serious stray corrosion.This paper reports a series of investigations of the electrochemical jet machining of titanium alloy parts.Based on the flow analysis and experiments,the machining flow field was effectively constrained.TB6 titanium alloy part with a perimeter of one meter was machined.The machined surface was smooth with no obvious machining defects.The machining process was particularly stable with no obvious spark discharge.The research provides a reference for the application of electrochemical jet machining technology to achieve large allowance material removal in the machining of large titanium alloy parts.
基金National Natural Science Foundation of China(51572224)Guangdong Young Creative Talents(2023KQNCX039)+2 种基金Guangdong Basic and Applied Basic Research Foundation(2023A1515110551)Innovative Team in Higher Educational Institutions of Guangdong Province(2020KCXTD039)2023 Lingnan Normal College Students Innovation and Entrepreneurship Training Program(1742)。
文摘The influence of graphene platelets(GPLs)on the WC grain size of WC-Co-GPLs cemented carbide prepared by low-pressure sintering was investigated.The role of GPLs in refining WC grains was explored by characterizing grain size and phase distribution.Results show that the addition of GPLs leads to significant grain refinement of WC and the more uniform distribution of WC grain size.When the content of GPLs is 0.10wt%,the average WC grain size in the cemented carbide is 0.39μm,which is 32%lower than that in WC-Co.However,the shape of WC grains is almost unaffected,while the mean free path of Co decreases.The grain refinement of WC is attributed to the homogeneous distribution of GPLs between WC/WC and WC/Co grain boundaries,which hinders the solution and precipitation process of WC in liquid phase Co,as well as the migration and growth of WC grains.Additionally,GPLs can serve as heat transfer plates in materials to improve cooling efficiency,thus inhibiting the growth of WC grain.
基金financially supported by the National Natural Science Foundation of China(Nos.52174092,51904290,and 52374147)the Natural Science Foundation of Jiangsu Province,China(No.BK20220157)+2 种基金the Fundamental Research Funds for the Central Universities,China(No.2022YCPY0202)the National Key Research and Development Program of China(No.2023YFC3804204)the Major Program of Xinjiang Uygur Autonomous Region S cience and Technology(No.2023A01002)。
文摘The mechanical behavior of cemented gangue backfill materials(CGBMs)is closely related to particle size distribution(PSD)of aggregates and properties of cementitious materials.Consequently,the true triaxial compression tests,CT scanning,SEM,and EDS tests were conducted on cemented gangue backfill samples(CGBSs)with various carbon nanotube concentrations(P_(CNT))that satisfied fractal theory for the PSD of aggregates.The mechanical properties,energy dissipations,and failure mechanisms of the CGBSs under true triaxial compression were systematically analyzed.The results indicate that appropriate carbon nanotubes(CNTs)effectively enhance the mechanical properties and energy dissipations of CGBSs through micropore filling and microcrack bridging,and the optimal effect appears at P_(CNT)of 0.08wt%.Taking PSD fractal dimension(D)of 2.500 as an example,compared to that of CGBS without CNT,the peak strength(σ_(p)),axial peak strain(ε_(1,p)),elastic strain energy(Ue),and dissipated energy(U_(d))increased by 12.76%,29.60%,19.05%,and90.39%,respectively.However,excessive CNTs can reduce the mechanical properties of CGBSs due to CNT agglomeration,manifesting a decrease inρ_(p),ε_(1,p),and the volumetric strain increment(Δε_(v))when P_(CNT)increases from 0.08wt%to 0.12wt%.Moreover,the addition of CNTs improved the integrity of CGBS after macroscopic failure,and crack extension in CGBSs appeared in two modes:detour and pass through the aggregates.Theσ_(p)and U_(d)firstly increase and then decrease with increasing D,and porosity shows the opposite trend.Theε_(1,p)andΔε_(v)are negatively correlated with D,and CGBS with D=2.150 has the maximum deformation parameters(ε_(1,p)=0.05079,Δε_(v)=0.01990)due to the frictional slip effect caused by coarse aggregates.With increasing D,the failure modes of CGBSs are sequentially manifested as oblique shear failure,"Y-shaped"shear failure,and conjugate shear failure.
文摘A gold catalyst of Au/pyrenyl‑graphdiyne(Pyr‑GDY)was prepared by anchoring small size of gold nanoparticles(Au NPs)on the surface of Pyr‑GDY for electrocatalytic nitrogen reduction reaction(eNRR),in which Au NPs with a size of approximately 3.69 nm was evenly distributed on spongy‑like porous Pyr‑GDY.The catalyst exhibited a good electrocatalytic activity for N_(2)reduction in a nitrogen‑saturated electrolyte,with an ammonia yield of 32.1μg·h^(-1)·mg_(cat)^(-1)at-0.3 V(vs RHE),3.5 times higher than that of Au/C(Au NPs anchored on carbon black).In addition,Au/Pyr‑GDY showed a Faraday efficiency(FE)of 26.9%for eNRR,and a good catalysis durability for over 22 h.
基金Foundation of Northwest Institute for Nonferrous Metal Research(ZZXJ2203)Capital Projects of Financial Department of Shaanxi Province(YK22C-12)+3 种基金Innovation Capability Support Plan in Shaanxi Province(2023KJXX-083)Key Research and Development Projects of Shaanxi Province(2024GXYBXM-351,2024GX-YBXM-356)National Natural Science Foundation of China(62204207,12204383)Xi'an Postdoctoral Innovation Base Funding Program。
文摘The extraordinary strength of metal/graphene composites is significantly determined by the characteristic size,distribution and morphology of graphene.However,the effect of the graphene size/distribution on the mechanical properties and related strengthening mechanisms has not been fully elucidated.Herein,under the same volume fraction and distribution conditions of graphene,molecular dynamics simulations were used to investigate the effect of graphene sheet size on the hardness and deformation behavior of Cu/graphene composites under complex stress field.Two models of pure single crystalline Cu and graphene fully covered Cu matrix composite were constructed for comparison.The results show that the strengthening effect changes with varying the graphene sheet size.Besides the graphene dislocation blocking effect and the load-bearing effect,the deformation mechanisms change from stacking fault tetrahedron,dislocation bypassing and dislocation cutting to dislocation nucleation in turn with decreasing the graphene sheet size.The hardness of Cu/graphene composite,with the graphene sheet not completely covering the metal matrix,can even be higher than that of the fully covered composite.The extra strengthening mechanisms of dislocation bypassing mechanism and the stacking fault tetrahedra pinning dislocation mechanism contribute to the increase in hardness.
基金supported by the Scientific Research Project funded by the Qingdao Postdoctoral Science Foundation(No.QDBSH20230102075)the China Postdoctoral Science Foundation(No.2023M733337)the National Natural Science Foundation of China(No.U2141251).
文摘All maritime industries are plagued by marine biofouling pollution,which causes large economic and environmental costs.Therefore,there is an urgent need for ecofriendly alternatives that can effectively reduce the negative consequences of biofouling pollution.This study aimed to produce novel capsaicin-inspired amide derivatives(CIADs)with multifunctional antifouling features by introducing amide compounds to aromatic compounds via a Friedel-Crafts alkylation reaction.The structure of the CIADs was characterized using FTIR,1H NMR,13C NMR,and HRMS,and the comprehensive antifouling capacity was determined by thermal stability,anti-ultraviolet,antibacterial,anti-algal,and marine field experiments.CIADs showed good thermal stability and did not show obvious weight loss before 226°C.2,4-dihydroxy-3,5-diphenylimidemet-hylbenzophenone(DDB)had an excellent ultraviolet absorption effect,which was even better than that of 2-hydroxy-4-(octyloxy)benzophenone.The antibacterial and anti-algal rates of N-(2,4-dimethyl-3-chloro-5-benzamide-methyl-6-hydroxybenzyl)benzamide(NDCBHB)were more than 99.5%and 64.0%,respectively,and the surface of antifouling coating with NDCBHB(NDCBHB-AC)was covered with only a small amount of sludge and biofilm,its antifouling effect was better than that of chlorothalonil.The above work provides a reference for preparing green and multifunctional antifouling agents.
基金supported by the Research Projects of Department of Education of Guangdong Province-024CJPT002Special Project of Guangdong Provincial Department of Education in Key Areas (No. 6021210075K)Shenzhen Polytechnic University Research Fund. (No. 6024310006K)
文摘Eco-friendly quantum-dot light-emitting diodes(QLEDs),which employ colloidal quantum dots(QDs)such as InP,and ZnSe,stand out due to their low toxicity,color purity,and high efficiency.Currently,significant advancements have been made in the performance of cadmium-free QLEDs.However,several challenges persist in the industrialization of ecofriendly QLED displays.For instance,(1)the poor performance,characterized by low photoluminescence quantum yield(PLQY),unstable ligand,and charge imbalance,cannot be effectively addressed with a solitary strategy;(2)the degradation mechanism,involving emission quenching,morphological inhomogeneity,and field-enhanced electron delocalization remains unclear;(3)the lack of techniques for color patterning,such as optical lithography and transfer printing.Herein,we undertake a specific review of all technological breakthroughs that endeavor to tackle the above challenges associated with cadmium-free QLED displays.We begin by reviewing the evolution,architecture,and operational characteristics of eco-friendly QLEDs,highlighting the photoelectric properties of QDs,carrier transport layer stability,and device lifetime.Subsequently,we focus our attention not only on the latest insights into device degradation mechanisms,particularly,but also on the remarkable technological progress in color patterning techniques.To conclude,we provide a synthesis of the promising prospects,current challenges,potential solutions,and emerging research trends for QLED displays.
文摘Constructed Wetlands (CWs) are currently one of the most promising techniques for wastewater treatment, having demonstrated their effectiveness. However, the choice of substrate particle size is critical to the smooth operation of the process, as hydrodynamic constraints require a coarse particle size, whereas wastewater treatment recommends a fine particle size. This study investigates the suitability of laterite and shale as substrates of different sizes (1 - 3, 3 - 5 and 5 - 8 mm) in CWs for domestic wastewater treatment. The study was carried out in an experimental pilot plant consisting of 12 parallelepiped beds (C × C = 0.4 × 0.4 m2;H = 0.6 m) filled from bottom to top with 0.1 m of gravel and 0.4 m of shale or laterite of different grain sizes with two replications. During the six months of operation, plant biomass and stem diameter of Pennisetum purpureum used as vegetation in the CWs were determined. Raw and treated water were also sampled and analyzed for pollutants, including chemical oxygen demand (COD), biochemical oxygen demand (BOD5), total Kjedahl nitrogen (TKN), total phosphorus (TP), and total suspended solids (TSS), using International Organization for Standardization (ISO) analytical methods. P. purpureum developed much better in the CW beds lined with shale;plant biomass ranged from 13.8 to 14.7 kg/m2 and from 11.2 to 12.5 kg/m2 in the beds lined with shale and laterite, respectively, as did stump diameter, which ranged from 15.5 to 16.1 cm and from 11.10 to 12.7 cm, respectively. However, the highest values for biomass and stump diameter for each material were obtained in the beds lined with 1 - 3 mm geomaterials. Pollutant removal efficiencies were highest in the CWs lined with laterite and shale of 1 - 3 mm grain size (76.9% - 83% COD, 78% - 84.7% BOD5, 55.5% - 72.2% TKN, 58.4% - 72.4% TP, 78.1% - 80.2% TSS), with the highest values recorded in the shale-lined beds. However, the 3 - 5 mm grain size of both materials provided quality filtrates (140 - 174 mg/L COD, 78.5 - 94.8 mg/L BOD5, 4.6 - 5.7 mg/L TP) in line with local wastewater discharge levels. This size of geomaterials appears to be suitable for optimization purposes, although further work with these materials, such as increasing the depth of the wetland, is required to improve the level of NTK and TSS discharge.
基金financially supported by CAMM(Center of Advanced Mining and Metallurgy/Green Flotation),as a center of excellence at the Luleå University of Technology.
文摘The global reliance on phosphate rock for agriculture and other industries,coupled with chemical regulations in developed countries,has driven the search for green alternatives in apatite flotation.This review investigates eco-friendly collectors’effectiveness in promoting sustainable mineral processing,guiding future alternatives to traditional reagents.The manuscript discussed the surface properties of apatite and its interaction with eco-friendly collectors,assessing existing fundamental studies.This study sought to:(1)define,organize,and classify“eco-friendly”collectors;(2)evaluate their effect in IEP and contact angle;(3)provide a better understanding of the adsorption behavior of the different fatty acid chains into apatite surface;(4)assess their ability to reversely and directly float apatite;(5)address gaps to achieve selectivity and process optimization.Outcomes demonstrated that fatty acids are largely applied,but other renewable sources of these reagents have been promisingly evaluated.In addition,other natural reagents have been tested,and new green synthetics have demonstrated synergistic effects when combined with fatty acids,yielding significant improvements in grade and recovery.However,collector effectiveness varies with ore characteristics,like particle size and surface properties,which remain underexplored.Future research should design tailored collectors that align with mineralogical differences to enhance selectivity.
文摘Nowadays,the development of effective bioplastics aims to combine traditional plastics’functionality with environmentally friendly properties.The most effective and durable modern bioplastics are made from the edible part of crops.This forces bioplastics to competewith food production because the crops that produce bioplastics can also be used for human nutrition.That is why the article’s main focus is on creating bioplastics using renewable,non-food raw materials(cellulose,lignin,etc.).Eco-friendly composites based on a renewable bioplastic blend of polybutylene adipate-co-terephthalate,corn starch,and poly(lactic acid)with reed and hemp waste as a filler.The physic-chemical features of the structure and surface,as well as the technological characteristics of reed and hemp waste as the organic fillers for renewable bioplastic blend of polybutylene adipate-co-terephthalate,corn starch,and poly(lactic acid),were studied.Theeffect of the fractional composition analysis,morphology,and nature of reed and hempwaste on the quality of the design of eco-friendly biodegradable composites and their ability to disperse in the matrix of renewable bioplastic blend of polybutylene adipate-co-terephthalate,corn starch and poly(lactic acid)was carried out.The influence of different content and morphology of reed and hemp waste on the composite characteristics was investigated.It is shown that the most optimal direction for obtaining strong eco-friendly biodegradable composites based on a renewable bioplastic blend of polybutylene adipate-co-terephthalate,corn starch,and poly(lactic acid)is associated with the use of waste reed stalks,with its optimal content at the level of 50 wt.%.
基金supported by the National Natural Science Foundation of China(Nos.51902036,52071295,52002352)Natural Science Foundation of Chongqing Science&Technology Commission(Nos.cstc2019jcyj-msxm1407 and CSTB2022NSCQ-MSX0828)+2 种基金the Venture&Innovation Support Program for Chongqing Overseas Returnees(No.CX2021046)the Science and Technology Research Program of Chongqing Municipal Education Commission(No.KJZDK202300802)Research Project of Innovative Talent Training Engineering Program of Chongqing Primary and Secondary School(No.CY230801).
文摘Even the sulfur cathode in lithium-sulfur(Li-S)battery has the advantages of high theoretical energy density,wide source of raw materials,no pollution to the environment,and so on.It still suffers the sore points of easy electrode collapse due to large volume expansion during charge and discharge and low active materials utilization caused by the severe shuttle effect of lithium polysulfides(LiPSs).Therefore,in this work,ramie gum(RG)was extracted from ramie fiber degumming liquid and used as the functional binder to address the above problems and improve the Li-S battery’s performance for the first time.Surprisingly,the sulfur cathode using RG binder illustrates a high initial capacity of 1152.2 mAh/g,and a reversible capacity of 644.6 mAh/g after 500 cycles at 0.5 C,far better than the sulfur cathode using polyvinylidene fluoride(PVDF)and sodium carboxymethyl cellulose(CMC)binder.More importantly,even if the active materials loading increased to as high as 4.30 mg/cm^(2),the area capacity is still around 3.1 mAh/cm^(2)after 200 cycles.Such excellent performances could be attributed to the abundant oxygen-and nitrogen-containing functional groups of RG that can effectively inhibit the shuttle effect of LiPSs,as well as the excellent viscosity and mechanical properties that can maintain electrode integrity during long-term charging/discharging.This work verifies the feasibility of RG as an eco-friendly and high-performance Li-S battery binder and provides a new idea for the utilization of agricultural biomass resources.
文摘This study evaluates the performance of advanced machine learning(ML)models in predicting the mechanical properties of eco-friendly self-compacting concrete(SCC),with a focus on compressive strength,V-funnel time,Lbox ratio,and slump flow.The motivation for this study stems from the increasing need to optimize concrete mix designs while minimizing environmental impact and reducing the reliance on costly physical testing.Six ML models-backpropagation neural network(BPNN),random forest regression(RFR),K-nearest neighbors(KNN),stacking,bagging,and eXtreme gradient boosting(XGBoost)-were trained and validated using a comprehensive dataset of 239 mix design parameters.The models'predictive accuracies were assessed using the coefficient of determination,mean squared error,root mean squared error,and mean absolute error.XGBoost consistently outperformed other models,achieving the coefficient of determination values of 0.999,0.933,and 0.935 for compressive strength in the training,validation,and testing datasets,respectively.Sensitivity analysis revealed that cement,silica fume,coarse aggregate,and superplasticizer positively influenced compressive strength,while water content had a negative impact.These findings highlight the potential of ML models,particularly XGBoost and RFR,in optimizing SCC mix designs,reducing reliance on physical testing,and enhancing sustainability in construction.The application of these models can lead to more efficient and eco-friendly concrete mix designs,benefiting real-world construction projects by improving quality control and reducing costs.
基金supported by the National Key Research and Development Program of China(Grant Nos.2023YFA1406000 and 2022YFA1403800)the National Natural Science Foundation of China(Grant Nos.12474002,22171283,22203031,12434005,12204515,and 12074175)support of the Young Elite Scientists Sponsorship Program by CAST(Grant No.2022QNRC001)。
文摘Kitaev quantum spin liquids have attracted significant attention in condensed matter physics over the past decade.To understand their emergent quantum phenomena,high-quality single crystals of substantial size are essential.Here,we report the synthesis of single crystals of the Kitaev quantum spin liquid candidate RuBr_(3),achieving millimeter-sized crystals through a self-flux method under high pressure and high temperature conditions.The crystals exhibit well-defined cleavage planes with a lustrous appearance.Transport characterizations exhibit a narrow band-gap semiconducting behavior with 0.13 eV and 0.11 eV band-gap in ab plane and along𝑐axis,respectively.Magnetic measurement shows a transition to antiferromagnetic(AFM)state at approximately 29K both in ab plane and along the c axis.Notably,the N′eel temperature increases to 34K with an applied magnetic field of up to 7T in the ab plane,but without any change along𝑐axis.The large size and high quality of RuBr3 single crystals provide a valuable platform for investigating various interactions,particularly the Kitaev interaction,and for elucidating the intrinsic physical properties of Kitaev quantum spin liquids.
基金supported by a grant from the National Natural Science Foundation of China(No.82202974)。
文摘To the Editor:Thymic carcinoma is a highly aggressive subtype of thymomas,accounting for 1%of thymic malignancies.It predominantly(80%)manifests in the anterosuperior mediastinum[1].Nevertheless,the occurrence of extrathoracic metastases,particularly liver metastases,is uncommon.The clinical manifestation of thymic carcinoma accompanied by liver metastases is characterized by ambiguous and nonspecific symptoms.Consequently,it is challenging to ascertain.
基金supported by National Natural Science Foundation of China under(Grant No.U2142206)the Shanghai Natural Science Foundation(21ZR1477300)+1 种基金Shanghai Science and Technology Commission Project(23DZ1204701)National Natural Science Foundation of China(Grant No.42075056)。
文摘This study investigates the size characteristics and related temporal variations of tropical cyclones(TCs)over the Western North Pacific(WNP)and those affecting East China(EC)using Joint Typhoon Warning Center(JTWC)data during 2001-20.The average size of EC TCs is found to be similar to that over the WNP.Furthermore,the annual maximum lifetime maximum size(LMS)of EC TCs shows a statistically significant increasing trend,implying a more severe impact on the EC region.Composite analyses of intensity and size variation over the entire lifetime of TCs,before and after re-curvature,and before and after rapid intensification(RI),show that there are significant differences between them in some key areas:(1)The intensity begins to rapidly decrease after the TC has reached its highest intensity,but the size remains quasi-constant;(2)When a TC recurves south of 15°N or north of 30°N,the variation trend for both intensity and size are broadly similar before and after curvature,but their variation trends are opposite when the recurvature occurs between 15°-30°N;(3)After RI,the intensity reaches its peak value within 24 h,whereas the size reaches its LMS after30-48 h.A significant correlation is also found between the rate of change in intensity and that of size during the development stage,with a correlation coefficient of 0.67 and 0.73 for TCs in the WNP and EC,respectively.However,no significant correlation exists during the weakening stage.
