Metamorphic mechanism has the advantages of variable topology and variable degrees of freedom, which can realize the requirements of multi-conditions and multi-tasks, and has a good application prospect. The configura...Metamorphic mechanism has the advantages of variable topology and variable degrees of freedom, which can realize the requirements of multi-conditions and multi-tasks, and has a good application prospect. The configuration transformation is prominent feature of the metamorphic mechanism. The number of constraints or properties of the kinematic pairs provided by the metamorphic kinematic pairs will change under certain conditions, its dynamic performance is much more complex than that of traditional kinematic pairs with immutable constraints. However, the clearance model about traditional kinematic pairs with immutable constraints established by long-term research is difficult to be directly applied to the metachromatic kinematic pairs. Referring to the experience of the traditional kinematic pairs with immutable constraints, the continuous contact model of Metamorphic Groove pin pair with clearance is established. According to the traditional continuous contact model of the kinematic pairs with immutable constraints, the forces between the elements of kinematic pair of the mechanism with clearance and the ideal mechanism without clearance are regarded as the same, and the inertia force and inertia moment of the components are also calculated according to the acceleration of the ideal mechanism. The clearance is regarded as a massless virtual bar with length r. For the rotating pair part, the massless virtual bar length r is the difference between the radius of the shaft and the hole, and for the sliding pair part, the massless virtual bar length r is half of the difference between the height of the slider and the guide groove. According to the new mechanism without gap after adding the imaginary bar, kinetic energy and potential energy of the system are calculated for the two configurations of mechanism with metamorphic Groove pin pair with clearance. The kinetic energy and potential energy of the system are calculated according to the new mechanism without clearance after adding the massless virtual bar. The kinetic energy, potential energy and generalized force are substituted into the Lagrangian equation to obtain the motion equation of the metamorphic mechanism, which lays the foundation for the dynamic performance study of the mechanism with metamorphic groove pin pair with clearance.展开更多
In this study,two wheat-derived cadmium(Cd)-immobilizing endophytic Pseudomonas paralactis M14 and Priestia megaterium R27 were evaluated for their effects on wheat tissue Cd uptake under hydroponic conditions.Then,th...In this study,two wheat-derived cadmium(Cd)-immobilizing endophytic Pseudomonas paralactis M14 and Priestia megaterium R27 were evaluated for their effects on wheat tissue Cd uptake under hydroponic conditions.Then,the impacts of the biochar(BC),M14+R27(MR),and BC+MR treatments on wheat Cd uptake and the mechanisms involved were investigated at the jointing,heading,and mature stages of wheat plants under field-plot conditions.A hydroponic experiment showed that the MR treatment significantly decreased the above-ground tissue Cd content compared with theM14 or R27 treatment.The BC+MRtreatment reduced the grain Cd content by 51.5%-67.7%and Cd translocation factor at the mature stage of wheat plants and increased the organic matter-bound Cd content by 31%-75%in the rhizosphere soils compared with the BC or MR treatment.Compared with the BC or MR treatment,the relative abundances of the biomarkers associated with Gemmatimonas,Altererythrobacter,Gammaproteobacteria,Xanthomonadaceae,Phenylobacterium,and Nocardioides in the BC+MR-treated rhizosphere microbiome decreased and negatively correlated with the organic matter-bound Cd contents.In the BC+MR-treated root interior microbiome,the relative abundance of the biomarker belonging to Exiguobacterium increased and negatively correlated with the Cd translocation factor,while the relative abundance of the biomarker belonging to Pseudonocardiaceae decreased and positively correlated with the Cd translocation factor.Our findings suggested that the BC+MR treatment reduced Cd availability and Cd transfer through affecting the abundances of these specific biomarkers in the rhizosphere soil and root interior microbiomes,leading to decreased wheat grain Cd uptake in the contaminated soil.展开更多
Fluoropolymers promise all-solid-state lithium metal batteries(ASLMBs)but suffer from two critical challenges.The first is the trade-off between ionic conductivity(σ)and lithium anode reactions,closely related to hig...Fluoropolymers promise all-solid-state lithium metal batteries(ASLMBs)but suffer from two critical challenges.The first is the trade-off between ionic conductivity(σ)and lithium anode reactions,closely related to high-content residual solvents.The second,usually consciously overlooked,is the fluoropolymer's inherent instability against alkaline lithium anodes.Here,we propose indium-based metal-organic frameworks(In-MOFs)as a multifunctional promoter to simultaneously address these two challenges,using poly(vinylidene fluoride-hexafluoropropylene)(PVH)as the typical fluoropolymer.In-MOF plays a trio:(1)adsorbing and converting free residual solvents into bonded states to prevent their side reactions with lithium anodes while retaining their advantages on Li~+transport;(2)forming inorganic-rich solid electrolyte interphase layers to prevent PVH from reacting with lithium anodes and promote uniform lithium deposition without dendrite growth;(3)reducing PVH crystallinity and promoting Li-salt dissociation.Therefore,the resulting PVH/In-MOF(PVH-IM)showcases excellent electrochemical stability against lithium anodes,delivering a 5550 h cycling at 0.2 m A cm^(-2)with a remarkable cumulative lithium deposition capacity of 1110 m Ah cm^(-2).It also exhibits an ultrahighσof 1.23×10^(-3)S cm^(-1)at 25℃.Moreover,all-solid-state LiFePO_4|PVH-IM|Li full cells show outstanding rate capability and cyclability(80.0%capacity retention after 280 cycles at 0.5C),demonstrating high potential for practical ASLMBs.展开更多
The ineluctable introduction of lithium salt to polymer solid-state electrolytes incurs a compromise between strength,ionic conductivity,and thickness.Here,we propose Al_(2)O_(3)-coated polyimide(AO/PI)porous film as ...The ineluctable introduction of lithium salt to polymer solid-state electrolytes incurs a compromise between strength,ionic conductivity,and thickness.Here,we propose Al_(2)O_(3)-coated polyimide(AO/PI)porous film as a high-strength substrate to support fast-ion-conducting polymer-in-salt(PIS)solid-state electrolytes,aiming to suppress lithium dendrite growth and improve full-cell performance.The Al_(2)O_(3)coating layer not only refines the wettability of polyimide porous film to PIS,but also performs as a high modulus protective layer to suppress the growth of lithium dendrites.The resulting PI/AO@PIS exhibits a small thickness of only 35μm with an outstanding tensile strength of 11.3 MPa and Young's modulus of 537.6 MPa.In addition,the PI/AO@PIS delivers a high ionic conductivity of 0.1 m S/cm at 25°C.As a result,the PI/AO@PIS enables symmetric Li cells to achieve exceptional cyclability for over 1000 h at 0.1 m A/cm2without noticeable lithium dendrite formation.Moreover,the PI/AO@PIS-based LiFePO4||Li full cells demonstrate outstanding rate performance(125.7 m Ah/g at 5 C)and impressive cycling stability(96.1%capacity retention at 1 C after 200 cycles).This work highlights the efficacy of enhancing the mechanical properties of polymer matrices and extending cell performance through the incorporation of a dense inorganic interface layer.展开更多
Composite solid electrolytes(CSEs)are promising for solid-state Li metal batteries but suffer from inferior room-temperature ionic conductivity due to sluggish ion transport and high cost due to expensive active ceram...Composite solid electrolytes(CSEs)are promising for solid-state Li metal batteries but suffer from inferior room-temperature ionic conductivity due to sluggish ion transport and high cost due to expensive active ceramic fillers.Here,a host–vip inversion engineering strategy is proposed to develop superionic CSEs using cost-effective SiO_(2) nanoparticles as passive ceramic hosts and poly(vinylidene fluoride-hexafluoropropylene)(PVH)microspheres as polymer vips,forming an unprecedented“polymer vip-in-ceramic host”(i.e.,PVH-in-SiO_(2))architecture differing from the traditional“ceramic vip-in-polymer host”.The PVH-in-SiO_(2) exhibits excellent Li-salt dissociation,achieving high-concentration free Li+.Owing to the low diffusion energy barriers and high diffusion coefficient,the free Li+is thermodynamically and kinetically favorable to migrate to and transport at the SiO_(2)/PVH interfaces.Consequently,the PVH-in-SiO_(2) delivers an exceptional ionic conductivity of 1.32.10−3 S cm−1 at 25℃(vs.typically 10−5–10−4 S cm−1 using high-cost active ceramics),achieved under an ultralow residual solvent content of 2.9 wt%(vs.8–15 wt%in other CSEs).Additionally,PVH-in-SiO_(2) is electrochemically stable with Li anode and various cathodes.Therefore,the PVH-in-SiO_(2) demonstrates excellent high-rate cyclability in LiFePO4|Li full cells(92.9%capacity-retention at 3C after 300 cycles under 25℃)and outstanding stability with high-mass-loading LiFePO4(9.2 mg cm−1)and high-voltage NCM622(147.1 mAh g−1).Furthermore,we verify the versatility of the host–vip inversion engineering strategy by fabricating Na-ion and K-ion-based PVH-in-SiO_(2) CSEs with similarly excellent promotions in ionic conductivity.Our strategy offers a simple,low-cost approach to fabricating superionic CSEs for large-scale application of solid-state Li metal batteries and beyond.展开更多
Halide solid-state electrolytes(HSSEs)with excellent ionic conductivity and high voltage stability are promising for all-solid-state Li-ion batteries(ASSLBs).However,they suffer from poor processability,mechanical dur...Halide solid-state electrolytes(HSSEs)with excellent ionic conductivity and high voltage stability are promising for all-solid-state Li-ion batteries(ASSLBs).However,they suffer from poor processability,mechanical durability and humidity stability,hindering their large-scale applications.Here,we introduce a dry-processing fibrillation strategy using hydrophobic polytetrafluoroethylene(PTFE)binder to encapsulate Li_(3)InCl_(6)(LIC)particles(the most representative HSSE).By manipulating the fibrillating process,only 0.5 wt%PTFE is sufficient to prepare free-standing LIC-PTFE(LIC-P)HSSEs.Additionally,LIC-P demonstrates excellent mechanical durability and humidity resistance.They can maintain their shapes after being exposed to humid atmosphere for 30 min,meanwhile still exhibit high ionic conductivity of>0.2m S/cm at 25℃.Consequently,the LIC-P-based ASSLBs deliver a high specific capacity of 126.6 m Ah/g at0.1 C and long cyclability of 200 cycles at 0.2 C.More importantly,the ASSLBs using moisture-exposed LIC-P can still operate properly by exhibiting a high capacity-retention of 87.7%after 100 cycles under0.2 C.Furthermore,for the first time,we unravel the LIC interfacial morphology evolution upon cycling because the good mechanical durability enables a facile separation of LIC-P from ASSLBs after testing.展开更多
The discrete fracture system of a rock mass plays a crucial role in controlling the stability of rock slopes.To fully account for the geometric shape and distribution characteristics of jointed rock masses,terrestrial...The discrete fracture system of a rock mass plays a crucial role in controlling the stability of rock slopes.To fully account for the geometric shape and distribution characteristics of jointed rock masses,terrestrial laser scanning(TLS)was employed to acquire high-resolution point-cloud data,and a developed automatic discontinuity-identification technology was coupled to automatically interpret and characterize geometric information such as orientation,trace length,spacing,and set number of the discontinuities.The discrete element method(DEM)was applied to study the influence of the geometric morphology and distribution characteristics of discontinuities on slope stability by generating a discrete fracture network(DFN)with the same statistical characteristics as the actual discontinuities.Based on slope data from the Yebatan Hydropower Station,a simulation was conducted to verify the applicability of the automatic discontinuity identification technology and the discrete fracture network-discrete element method(DFN-DEM).Various geological parameters,including trace length,persistence,and density,were examined to investigate the morphological evolution and response characteristics of rock slope excavation under different joint combination conditions through simulation.The simulation results indicate that joint parameters affect slope stability,with density having the most significant impact.The impact of joint parameters on stability is relatively small within a reasonable range but becomes significant beyond a certain threshold,further validating that the accuracy of field geological surveys is critical for simulation.This study provides a scientific basis for the construction of complex rock slope models,engineering assessments,and disaster prevention and mitigation,which is of great value in both theory and engineering applications.展开更多
The river plume front between the diluted ocean water and salty ocean water in the Changjiang(Yangtze)River Delta(CRD)is well studied.Comparatively,less is known about the estuarine front in the CRD,which is formed be...The river plume front between the diluted ocean water and salty ocean water in the Changjiang(Yangtze)River Delta(CRD)is well studied.Comparatively,less is known about the estuarine front in the CRD,which is formed between the riverine freshwater and the diluted ocean water and has the highest magnitude of salinity gradient(SG)in the CRD.Estuarine fronts are of great significance to the riverine material transport in the estuary.Many biogeochemical processes are enhanced in estuarine fronts,which have brought about environmental problems.In this study,the seasonal variations of the estuarine fronts in the CRD were studied in wet(July)and dry(January)seasons in 2017,based on model simulations with high spatiotemporal resolutions using the Finite-Volume Community Ocean Model(FVCOM).The estuarine front included several sharp fronts with a SG>4(/500 m),and was bottom-trapped on the submerged delta front.Seasonal changes mainly occurred off the Jiangsu coast,where a significant estuarine front was formed in July.The estuarine fronts generated around the submerged delta topography were accompanied by the offshore extension of older estuarine fronts,which were diluted and evolved into plume fronts over a tidal cycle.The simulated estuarine fronts had a salinity range of 6 to 22 in the dry season and 6 to 14 in wet season 2017.The estuarine fronts hindered the residual current by altering its flow direction to the southeast.展开更多
The Lower Cambrian Longwangmiao Formation shoal dolostone reservoir in Sichuan Basin is currently an exploration and research highlight in China. Reservoir rocks mainly consist of crystalline dolomite with residual gr...The Lower Cambrian Longwangmiao Formation shoal dolostone reservoir in Sichuan Basin is currently an exploration and research highlight in China. Reservoir rocks mainly consist of crystalline dolomite with residual grain texture, and dolarenite of which the arene is mainly composed of muddy to micritic dolomite with some crystalline grain directionally aligned. The trace element indicates that the dolomites of Longwangmiao Formation may be related to the high salinity of sea water. The oxygen isotope values of crystalline dolomite and dolarenite are both similar to that of the Early Cambrian marine dolomites, and the carbon isotope values of every kind of dolomites are completely overlapped with that of the seawater in Early Cambrian, indicating the dolomitization fluid is originated from the Early Cambrian sea water. The restricted marine biological communities and a small amount of gypsum pseudonodule seen in muddy to micritic dolomite indicate that the sea water in Early Cambrian was restricted and evaporated. However, the general lack of massive evaporite mineral and gypsum karst breccia indicates that the salinity of sea water during dolomitization was lower than the value of gypsum＇s precipitation. The Longwangmiao Formation consists of several high-frequency sedimentary cycles, indicating frequent sea level changes. This study indicates that massive dolomitization may also occur in underwater palaeohigh in carbonate platform through the reflux of penesaline sea water driven by a combination of high-and low-frequency sea-level changes. This kind of dolomitization can explain the generation of massive dolomites in the absence of evaporite precipitation, and further indicates that replacement dolomites can be produced by sea water with a wide range of salinity（normal, penesaline to hypersaline）.展开更多
The emergence of polymerized small molecule acceptors(PSMAs)has significantly improved the performance of all-polymer solar cells(all-PSCs).However,the pace of device engineering lacks behind that of materials develop...The emergence of polymerized small molecule acceptors(PSMAs)has significantly improved the performance of all-polymer solar cells(all-PSCs).However,the pace of device engineering lacks behind that of materials development,so that a majority of the PSMAs have not fulfilled their potentials.Furthermore,most high-performance all-PSCs rely on the use of chloroform as the processing solvent.For instance,the recent highperformance PSMA,named PJ1-γ,with high LUMO,and HOMO levels,could only achieve a PCE of 16.1%with a high-energy-level donor(JD40)using chloroform.Herein,we present a methodology combining sequential processing(SqP)with the addition of 0.5%wt PC_(71)BM as a solid additive(SA)to achieve an impressive efficiency of 18.0%for all-PSCs processed from toluene,an aromatic hydrocarbon solvent.Compared to the conventional blend-casting(BC)method whose best efficiency(16.7%)could only be achieved using chloroform,the SqP method significantly boosted the device efficiency using toluene as the processing solvent.In addition,the donor we employ is the classic PM6 that has deeper energy levels than JD40,which provides low energy loss for the device.We compare the results with another PSMA(PYF-T-o)with the same method.Finally,an improved photostability of the SqP devices with the incorporation of SA is demonstrated.展开更多
Realizing high-rate capability and high-efficiency utilization of polyanionic cathode materials is of great importance for practical sodium-ion batteries(SIBs) since they usually suffer from extremely low electronic c...Realizing high-rate capability and high-efficiency utilization of polyanionic cathode materials is of great importance for practical sodium-ion batteries(SIBs) since they usually suffer from extremely low electronic conductivity and limited ionic diffusion kinetics. Herein, taking Na_(3.5)V_(1.5)Mn_(0.5)(PO_(4))_(3)(NVMP) as an example, a reinforced concrete-like hierarchical and porous hybrid(NVMP@C@3DPG) built from 3D graphene(“rebar”) frameworks and in situ generated carbon coated NVMP(“concrete”) has been developed by a facile polymer assisted self-assembly and subsequent solid-state method. Such hybrids deliver superior rate capability(73.9 m Ah/g up to 20 C) and excellent cycling stability in a wide temperature range with a high specific capacity of 88.4 m Ah/g after 5000 cycles at 15 C at room temperature, and a high capacity retention of 97.1% after 500 cycles at 1 C(-20 ℃), and maintaining a high reversible capacity of 110.3 m Ah/g in full cell. This work offers a facile and efficient strategy to develop advanced polyanionic cathodes with high-efficiency utilization and 3D electron/ion transport systems.展开更多
All-solid-state lithium batteries(ASSLBs)based on sulfide electrolytes promise next-generation energy storage with high energy density and safety.However,the sulfide electrolytes suffer from phase instability and slug...All-solid-state lithium batteries(ASSLBs)based on sulfide electrolytes promise next-generation energy storage with high energy density and safety.However,the sulfide electrolytes suffer from phase instability and sluggish interfacial charge transport when pairing with layered oxide cathodes at high voltages.Herein,a simple and efficient strategy is proposed using two-dimensional Ti_(3)C_(2)T_(x)MXene as starting material to in-situ construct a 15 nm Li_(2)TiO_(3) layer on a typical oxide cathode,LiCoO_(2).The in-situ transformation of Ti_(3)C_(2)T_(x)into Li_(2)TiO_(3) layer occurs at a low temperature of 500℃,avoiding the phase deterioration of LiCoO_(2).The thin Li_(2)TiO_(3) layer is Li^(+)conducting and electrochemically stable,thereby preventing the interfacial decomposition of sulfide electrolytes induced by LiCoO_(2) at high voltages and facilitating Li+transport at the interface.Moreover,Li_(2)TiO_(3) can stabilize the layer structure of LiCoO_(2) at high voltages.Consequently,the sulfide-based ASSLB using LiCoO_(2)@Li_(2)TiO_(3) cathode can operate stably at a high voltage of up to 4.5 V(vs.Li+/Li),delivering an outstanding initial specific discharge capacity of 138.8 m Ah/g with a high capacity retention of 86.2% after 100 cycles at 0.2 C.The in-situ transformation strategy may also apply to other MXenes,offering a general approach for constructing other advanced lithiated coatings for oxide cathodes.展开更多
Fishes are the largest group of vertebrates,representing more than half of all vertebrate species on Earth.Important aquaculture species,such as Atlantic salmon,cod,and large yellow croaker,contribute to over 16%of th...Fishes are the largest group of vertebrates,representing more than half of all vertebrate species on Earth.Important aquaculture species,such as Atlantic salmon,cod,and large yellow croaker,contribute to over 16%of the global seafood supply for human consumption(Food and Agriculture Organization of the United Nations,2020).Zebrafish(Danio rerio),medaka(Oryzias latipes),threespined stickleback(Gasterosteus aculeatus),and other fish species are important model organisms in life science research.展开更多
Background:Calcific aortic valve stenosis(CAVS)is one of the most challenging heart diseases in clinical with rapidly increasing prevalence.However,study of the mecha-nism and treatment of CAVS is hampered by the lack...Background:Calcific aortic valve stenosis(CAVS)is one of the most challenging heart diseases in clinical with rapidly increasing prevalence.However,study of the mecha-nism and treatment of CAVS is hampered by the lack of suitable,robust and efficient models that develop hemodynamically significant stenosis and typical calcium deposi-tion.Here,we aim to establish a mouse model to mimic the development and features of CAVS.Methods:The model was established via aortic valve wire injury(AVWI)combined with vitamin D subcutaneous injected in wild type C57/BL6 mice.Serial transthoracic echocardiography was applied to evaluate aortic jet peak velocity and mean gradi-ent.Histopathological specimens were collected and examined in respect of valve thickening,calcium deposition,collagen accumulation,osteogenic differentiation and inflammation.Results:Serial transthoracic echocardiography revealed that aortic jet peak velocity and mean gradient increased from 7 days post model establishment in a time depend-ent manner and tended to be stable at 28 days.Compared with the sham group,sim-ple AVWI or the vitamin D group,the hybrid model group showed typical pathological features of CAVS,including hemodynamic alterations,increased aortic valve thicken-ing,calcium deposition,collagen accumulation at 28 days.In addition,osteogenic dif-ferentiation,fibrosis and inflammation,which play critical roles in the development of CAVS,were observed in the hybrid model.Conclusions:We established a novel mouse model of CAVS that could be induced efficiently,robustly and economically,and without genetic intervention.It provides a fast track to explore the underlying mechanisms of CAVS and to identify more effec-tive pharmacological targets.展开更多
A liquid-microjet(LJ)linear time-of-flight(TOF)mass spectrometer,coupled with a femtosecond laser ionization source,has been designed for direct measurements of mass spectra of liquid aqueous solutions.Two main featur...A liquid-microjet(LJ)linear time-of-flight(TOF)mass spectrometer,coupled with a femtosecond laser ionization source,has been designed for direct measurements of mass spectra of liquid aqueous solutions.Two main features of our designed spectrometer involve the coupling of a liquid microjet nozzle to a conventional ion optics and the application of femtosecond pulses for mass spectral ionization.The detailed design,construction,and simulation of this new spectrometer are presented.More importantly,we combined the experimental tests with the simulated electric fields and ion trajectories to investigate the performance of the designed spectrometer,especially the kind of disturbances of the nozzle electric field on the conventional ion optics.In our current design,the optimal E/R(E:extractor,R:repeller)electrode voltage ratio was found to be∼0.71 when the voltages on the R,E and G(ground)electrodes were set to be 1500,1060 and 0 V,respectively,whilst the voltage on the N nozzle electrode was required to be around 1250 V.The capability of the designed spectrometer has been demonstrated by recording the simulated mass spectra of the water,benzene and cytidine with their mass/charge ratios of 18,76 and 243,respectively.This work shall be helpful for the development of new all-liquid-phase mass spectral technology to be employed in the diagnosis of diseases by the mass analysis of human body fluids.展开更多
Ionic polymer-metal composites(IPMCs)constitute a new type of artificial muscle material that is commonly used in bionic soft robots and medical devices because of its small driving voltage and considerable deformatio...Ionic polymer-metal composites(IPMCs)constitute a new type of artificial muscle material that is commonly used in bionic soft robots and medical devices because of its small driving voltage and considerable deformation.However,IPMCs are limited by performance issues such as low output force and small operating time away from water.Silicon dioxide sulfonated graphene(SiO_(2)-SGO)particles are often used to improve the performance of polymer membranes because of their hydrophilicity and high chemical stability.Reported here is the addition of SiO_(2)-SGO particles prepared by in situ hydrolysis to perfluorosulfonic acid in order to improve the IPMC properties.Also,a predictive model was constructed based on a backpropagation neural network,with the SiO_(2)-SGO doping amount and the IPMC excitation voltage in the input layer and the driving displacement in the output layer.The results show that the IPMC prepared with 1.0 wt.%doping content performed the best,with a maximum output displacement of 47.7 mm.The correlation coefficient(R2)was 0.9842 and the mean square error was 0.00037073,which show that the predictive model has high predictive accuracy and is suitable for predicting the performance of the SiO_(2)-SGO-modified IPMC.展开更多
文摘Metamorphic mechanism has the advantages of variable topology and variable degrees of freedom, which can realize the requirements of multi-conditions and multi-tasks, and has a good application prospect. The configuration transformation is prominent feature of the metamorphic mechanism. The number of constraints or properties of the kinematic pairs provided by the metamorphic kinematic pairs will change under certain conditions, its dynamic performance is much more complex than that of traditional kinematic pairs with immutable constraints. However, the clearance model about traditional kinematic pairs with immutable constraints established by long-term research is difficult to be directly applied to the metachromatic kinematic pairs. Referring to the experience of the traditional kinematic pairs with immutable constraints, the continuous contact model of Metamorphic Groove pin pair with clearance is established. According to the traditional continuous contact model of the kinematic pairs with immutable constraints, the forces between the elements of kinematic pair of the mechanism with clearance and the ideal mechanism without clearance are regarded as the same, and the inertia force and inertia moment of the components are also calculated according to the acceleration of the ideal mechanism. The clearance is regarded as a massless virtual bar with length r. For the rotating pair part, the massless virtual bar length r is the difference between the radius of the shaft and the hole, and for the sliding pair part, the massless virtual bar length r is half of the difference between the height of the slider and the guide groove. According to the new mechanism without gap after adding the imaginary bar, kinetic energy and potential energy of the system are calculated for the two configurations of mechanism with metamorphic Groove pin pair with clearance. The kinetic energy and potential energy of the system are calculated according to the new mechanism without clearance after adding the massless virtual bar. The kinetic energy, potential energy and generalized force are substituted into the Lagrangian equation to obtain the motion equation of the metamorphic mechanism, which lays the foundation for the dynamic performance study of the mechanism with metamorphic groove pin pair with clearance.
基金supported by the National Natural Science Foundation of China(No.41977199).
文摘In this study,two wheat-derived cadmium(Cd)-immobilizing endophytic Pseudomonas paralactis M14 and Priestia megaterium R27 were evaluated for their effects on wheat tissue Cd uptake under hydroponic conditions.Then,the impacts of the biochar(BC),M14+R27(MR),and BC+MR treatments on wheat Cd uptake and the mechanisms involved were investigated at the jointing,heading,and mature stages of wheat plants under field-plot conditions.A hydroponic experiment showed that the MR treatment significantly decreased the above-ground tissue Cd content compared with theM14 or R27 treatment.The BC+MRtreatment reduced the grain Cd content by 51.5%-67.7%and Cd translocation factor at the mature stage of wheat plants and increased the organic matter-bound Cd content by 31%-75%in the rhizosphere soils compared with the BC or MR treatment.Compared with the BC or MR treatment,the relative abundances of the biomarkers associated with Gemmatimonas,Altererythrobacter,Gammaproteobacteria,Xanthomonadaceae,Phenylobacterium,and Nocardioides in the BC+MR-treated rhizosphere microbiome decreased and negatively correlated with the organic matter-bound Cd contents.In the BC+MR-treated root interior microbiome,the relative abundance of the biomarker belonging to Exiguobacterium increased and negatively correlated with the Cd translocation factor,while the relative abundance of the biomarker belonging to Pseudonocardiaceae decreased and positively correlated with the Cd translocation factor.Our findings suggested that the BC+MR treatment reduced Cd availability and Cd transfer through affecting the abundances of these specific biomarkers in the rhizosphere soil and root interior microbiomes,leading to decreased wheat grain Cd uptake in the contaminated soil.
基金the financial support from the 261 Project of MIITNatural Science Foundation of Jiangsu Province(No.BK20240179)。
文摘Fluoropolymers promise all-solid-state lithium metal batteries(ASLMBs)but suffer from two critical challenges.The first is the trade-off between ionic conductivity(σ)and lithium anode reactions,closely related to high-content residual solvents.The second,usually consciously overlooked,is the fluoropolymer's inherent instability against alkaline lithium anodes.Here,we propose indium-based metal-organic frameworks(In-MOFs)as a multifunctional promoter to simultaneously address these two challenges,using poly(vinylidene fluoride-hexafluoropropylene)(PVH)as the typical fluoropolymer.In-MOF plays a trio:(1)adsorbing and converting free residual solvents into bonded states to prevent their side reactions with lithium anodes while retaining their advantages on Li~+transport;(2)forming inorganic-rich solid electrolyte interphase layers to prevent PVH from reacting with lithium anodes and promote uniform lithium deposition without dendrite growth;(3)reducing PVH crystallinity and promoting Li-salt dissociation.Therefore,the resulting PVH/In-MOF(PVH-IM)showcases excellent electrochemical stability against lithium anodes,delivering a 5550 h cycling at 0.2 m A cm^(-2)with a remarkable cumulative lithium deposition capacity of 1110 m Ah cm^(-2).It also exhibits an ultrahighσof 1.23×10^(-3)S cm^(-1)at 25℃.Moreover,all-solid-state LiFePO_4|PVH-IM|Li full cells show outstanding rate capability and cyclability(80.0%capacity retention after 280 cycles at 0.5C),demonstrating high potential for practical ASLMBs.
基金the financial support from the 261Project of MIIT and Natural Science Foundation of Jiangsu Province(No.BK20240179)。
文摘The ineluctable introduction of lithium salt to polymer solid-state electrolytes incurs a compromise between strength,ionic conductivity,and thickness.Here,we propose Al_(2)O_(3)-coated polyimide(AO/PI)porous film as a high-strength substrate to support fast-ion-conducting polymer-in-salt(PIS)solid-state electrolytes,aiming to suppress lithium dendrite growth and improve full-cell performance.The Al_(2)O_(3)coating layer not only refines the wettability of polyimide porous film to PIS,but also performs as a high modulus protective layer to suppress the growth of lithium dendrites.The resulting PI/AO@PIS exhibits a small thickness of only 35μm with an outstanding tensile strength of 11.3 MPa and Young's modulus of 537.6 MPa.In addition,the PI/AO@PIS delivers a high ionic conductivity of 0.1 m S/cm at 25°C.As a result,the PI/AO@PIS enables symmetric Li cells to achieve exceptional cyclability for over 1000 h at 0.1 m A/cm2without noticeable lithium dendrite formation.Moreover,the PI/AO@PIS-based LiFePO4||Li full cells demonstrate outstanding rate performance(125.7 m Ah/g at 5 C)and impressive cycling stability(96.1%capacity retention at 1 C after 200 cycles).This work highlights the efficacy of enhancing the mechanical properties of polymer matrices and extending cell performance through the incorporation of a dense inorganic interface layer.
基金financial support from the National Natural Science Foundation of China(Nos.52250010 and 52201242)the 261 Project of MIIT,Natural Science Foundation of Jiangsu Province(No.BK20240179)the Young Elite Scientists Sponsorship Program by CAST(No.2021QNRC001).
文摘Composite solid electrolytes(CSEs)are promising for solid-state Li metal batteries but suffer from inferior room-temperature ionic conductivity due to sluggish ion transport and high cost due to expensive active ceramic fillers.Here,a host–vip inversion engineering strategy is proposed to develop superionic CSEs using cost-effective SiO_(2) nanoparticles as passive ceramic hosts and poly(vinylidene fluoride-hexafluoropropylene)(PVH)microspheres as polymer vips,forming an unprecedented“polymer vip-in-ceramic host”(i.e.,PVH-in-SiO_(2))architecture differing from the traditional“ceramic vip-in-polymer host”.The PVH-in-SiO_(2) exhibits excellent Li-salt dissociation,achieving high-concentration free Li+.Owing to the low diffusion energy barriers and high diffusion coefficient,the free Li+is thermodynamically and kinetically favorable to migrate to and transport at the SiO_(2)/PVH interfaces.Consequently,the PVH-in-SiO_(2) delivers an exceptional ionic conductivity of 1.32.10−3 S cm−1 at 25℃(vs.typically 10−5–10−4 S cm−1 using high-cost active ceramics),achieved under an ultralow residual solvent content of 2.9 wt%(vs.8–15 wt%in other CSEs).Additionally,PVH-in-SiO_(2) is electrochemically stable with Li anode and various cathodes.Therefore,the PVH-in-SiO_(2) demonstrates excellent high-rate cyclability in LiFePO4|Li full cells(92.9%capacity-retention at 3C after 300 cycles under 25℃)and outstanding stability with high-mass-loading LiFePO4(9.2 mg cm−1)and high-voltage NCM622(147.1 mAh g−1).Furthermore,we verify the versatility of the host–vip inversion engineering strategy by fabricating Na-ion and K-ion-based PVH-in-SiO_(2) CSEs with similarly excellent promotions in ionic conductivity.Our strategy offers a simple,low-cost approach to fabricating superionic CSEs for large-scale application of solid-state Li metal batteries and beyond.
基金supported by the 261 Project of MIITthe National Natural Science Foundation of China(Nos.52250010,52201242,U23A20574)the Young Elite Scientists Sponsorship Program by CAST(No.2021QNRC001)。
文摘Halide solid-state electrolytes(HSSEs)with excellent ionic conductivity and high voltage stability are promising for all-solid-state Li-ion batteries(ASSLBs).However,they suffer from poor processability,mechanical durability and humidity stability,hindering their large-scale applications.Here,we introduce a dry-processing fibrillation strategy using hydrophobic polytetrafluoroethylene(PTFE)binder to encapsulate Li_(3)InCl_(6)(LIC)particles(the most representative HSSE).By manipulating the fibrillating process,only 0.5 wt%PTFE is sufficient to prepare free-standing LIC-PTFE(LIC-P)HSSEs.Additionally,LIC-P demonstrates excellent mechanical durability and humidity resistance.They can maintain their shapes after being exposed to humid atmosphere for 30 min,meanwhile still exhibit high ionic conductivity of>0.2m S/cm at 25℃.Consequently,the LIC-P-based ASSLBs deliver a high specific capacity of 126.6 m Ah/g at0.1 C and long cyclability of 200 cycles at 0.2 C.More importantly,the ASSLBs using moisture-exposed LIC-P can still operate properly by exhibiting a high capacity-retention of 87.7%after 100 cycles under0.2 C.Furthermore,for the first time,we unravel the LIC interfacial morphology evolution upon cycling because the good mechanical durability enables a facile separation of LIC-P from ASSLBs after testing.
基金We acknowledge the funding support from the National Key R&D Program of China(Grant No.2022YFC3080100)the National Natural Science Foundation of China(Grant No.42102316)the opening fund of State Key Laboratory of Hydraulics and Mountain River Engineering,Sichuan University(Grant No.SKHL2306).
文摘The discrete fracture system of a rock mass plays a crucial role in controlling the stability of rock slopes.To fully account for the geometric shape and distribution characteristics of jointed rock masses,terrestrial laser scanning(TLS)was employed to acquire high-resolution point-cloud data,and a developed automatic discontinuity-identification technology was coupled to automatically interpret and characterize geometric information such as orientation,trace length,spacing,and set number of the discontinuities.The discrete element method(DEM)was applied to study the influence of the geometric morphology and distribution characteristics of discontinuities on slope stability by generating a discrete fracture network(DFN)with the same statistical characteristics as the actual discontinuities.Based on slope data from the Yebatan Hydropower Station,a simulation was conducted to verify the applicability of the automatic discontinuity identification technology and the discrete fracture network-discrete element method(DFN-DEM).Various geological parameters,including trace length,persistence,and density,were examined to investigate the morphological evolution and response characteristics of rock slope excavation under different joint combination conditions through simulation.The simulation results indicate that joint parameters affect slope stability,with density having the most significant impact.The impact of joint parameters on stability is relatively small within a reasonable range but becomes significant beyond a certain threshold,further validating that the accuracy of field geological surveys is critical for simulation.This study provides a scientific basis for the construction of complex rock slope models,engineering assessments,and disaster prevention and mitigation,which is of great value in both theory and engineering applications.
基金Supported by the National Natural Science Foundation of China(No.U2240220)。
文摘The river plume front between the diluted ocean water and salty ocean water in the Changjiang(Yangtze)River Delta(CRD)is well studied.Comparatively,less is known about the estuarine front in the CRD,which is formed between the riverine freshwater and the diluted ocean water and has the highest magnitude of salinity gradient(SG)in the CRD.Estuarine fronts are of great significance to the riverine material transport in the estuary.Many biogeochemical processes are enhanced in estuarine fronts,which have brought about environmental problems.In this study,the seasonal variations of the estuarine fronts in the CRD were studied in wet(July)and dry(January)seasons in 2017,based on model simulations with high spatiotemporal resolutions using the Finite-Volume Community Ocean Model(FVCOM).The estuarine front included several sharp fronts with a SG>4(/500 m),and was bottom-trapped on the submerged delta front.Seasonal changes mainly occurred off the Jiangsu coast,where a significant estuarine front was formed in July.The estuarine fronts generated around the submerged delta topography were accompanied by the offshore extension of older estuarine fronts,which were diluted and evolved into plume fronts over a tidal cycle.The simulated estuarine fronts had a salinity range of 6 to 22 in the dry season and 6 to 14 in wet season 2017.The estuarine fronts hindered the residual current by altering its flow direction to the southeast.
基金supported by the National Natural Science Foundation of China (No.41602166)
文摘The Lower Cambrian Longwangmiao Formation shoal dolostone reservoir in Sichuan Basin is currently an exploration and research highlight in China. Reservoir rocks mainly consist of crystalline dolomite with residual grain texture, and dolarenite of which the arene is mainly composed of muddy to micritic dolomite with some crystalline grain directionally aligned. The trace element indicates that the dolomites of Longwangmiao Formation may be related to the high salinity of sea water. The oxygen isotope values of crystalline dolomite and dolarenite are both similar to that of the Early Cambrian marine dolomites, and the carbon isotope values of every kind of dolomites are completely overlapped with that of the seawater in Early Cambrian, indicating the dolomitization fluid is originated from the Early Cambrian sea water. The restricted marine biological communities and a small amount of gypsum pseudonodule seen in muddy to micritic dolomite indicate that the sea water in Early Cambrian was restricted and evaporated. However, the general lack of massive evaporite mineral and gypsum karst breccia indicates that the salinity of sea water during dolomitization was lower than the value of gypsum＇s precipitation. The Longwangmiao Formation consists of several high-frequency sedimentary cycles, indicating frequent sea level changes. This study indicates that massive dolomitization may also occur in underwater palaeohigh in carbonate platform through the reflux of penesaline sea water driven by a combination of high-and low-frequency sea-level changes. This kind of dolomitization can explain the generation of massive dolomites in the absence of evaporite precipitation, and further indicates that replacement dolomites can be produced by sea water with a wide range of salinity（normal, penesaline to hypersaline）.
基金supported by the Guangdong Basic and Applied Basic Research Foundation(2022A1515010875)Guangdong Basic and Applied Basic Research Foundation(2021A1515110017)+10 种基金Natural Science Foundation of Top Talent of SZTU(grant no.20200205)Project of Education Commission of Guangdong Province of China(2021KQNCX080)Research on the electrochemical reaction mechanism of the anode of mediumlow temperature direct ammonia SOFCs(20231063020006)the project of al solid-state high energy density energy storage system(20221063010031)the project of Shenzhen Overseas Talent upon Industrialization of 1kw stack for direct ammonia SOFCs(20221061010002)Guangdong Basic and Applied Basic Research Foundation(No.2019A1515011673)Education Department of Guangdong Province(No.2021KCXTD045)National Natural Science Foundation of China(No.12274303)the support from the Fundamental Research Funds for the Central Universities(2232023A-01)NSFC No.52103202beamline BL16B1 at Shanghai Synchrotron Radiation Facility(SSRF)for the synchrotron experiment
文摘The emergence of polymerized small molecule acceptors(PSMAs)has significantly improved the performance of all-polymer solar cells(all-PSCs).However,the pace of device engineering lacks behind that of materials development,so that a majority of the PSMAs have not fulfilled their potentials.Furthermore,most high-performance all-PSCs rely on the use of chloroform as the processing solvent.For instance,the recent highperformance PSMA,named PJ1-γ,with high LUMO,and HOMO levels,could only achieve a PCE of 16.1%with a high-energy-level donor(JD40)using chloroform.Herein,we present a methodology combining sequential processing(SqP)with the addition of 0.5%wt PC_(71)BM as a solid additive(SA)to achieve an impressive efficiency of 18.0%for all-PSCs processed from toluene,an aromatic hydrocarbon solvent.Compared to the conventional blend-casting(BC)method whose best efficiency(16.7%)could only be achieved using chloroform,the SqP method significantly boosted the device efficiency using toluene as the processing solvent.In addition,the donor we employ is the classic PM6 that has deeper energy levels than JD40,which provides low energy loss for the device.We compare the results with another PSMA(PYF-T-o)with the same method.Finally,an improved photostability of the SqP devices with the incorporation of SA is demonstrated.
基金financially supported by the National Natural Science Foundation of China (No.52072119)Natural Science Foundation of Hunan Province (No.2023JJ50015)+2 种基金the 111 Project (No.D20015)the Australian Research Council (No.DP230100198)the Echidna at the Australian centre for Neutron Scattering under Merit Programs (beamtime: M13623)。
文摘Realizing high-rate capability and high-efficiency utilization of polyanionic cathode materials is of great importance for practical sodium-ion batteries(SIBs) since they usually suffer from extremely low electronic conductivity and limited ionic diffusion kinetics. Herein, taking Na_(3.5)V_(1.5)Mn_(0.5)(PO_(4))_(3)(NVMP) as an example, a reinforced concrete-like hierarchical and porous hybrid(NVMP@C@3DPG) built from 3D graphene(“rebar”) frameworks and in situ generated carbon coated NVMP(“concrete”) has been developed by a facile polymer assisted self-assembly and subsequent solid-state method. Such hybrids deliver superior rate capability(73.9 m Ah/g up to 20 C) and excellent cycling stability in a wide temperature range with a high specific capacity of 88.4 m Ah/g after 5000 cycles at 15 C at room temperature, and a high capacity retention of 97.1% after 500 cycles at 1 C(-20 ℃), and maintaining a high reversible capacity of 110.3 m Ah/g in full cell. This work offers a facile and efficient strategy to develop advanced polyanionic cathodes with high-efficiency utilization and 3D electron/ion transport systems.
基金the financial support from the National Natural Science Foundation of China(Nos.52201242,52250010)Natural Science Foundation of Jiangsu Province(Nos.BK20200386,BK20200186)+1 种基金Young Elite Scientists Sponsorship Program by CAST(No.2021QNRC001)the Fundamental Research Funds for the Central Universities(No.2242022R40018)。
文摘All-solid-state lithium batteries(ASSLBs)based on sulfide electrolytes promise next-generation energy storage with high energy density and safety.However,the sulfide electrolytes suffer from phase instability and sluggish interfacial charge transport when pairing with layered oxide cathodes at high voltages.Herein,a simple and efficient strategy is proposed using two-dimensional Ti_(3)C_(2)T_(x)MXene as starting material to in-situ construct a 15 nm Li_(2)TiO_(3) layer on a typical oxide cathode,LiCoO_(2).The in-situ transformation of Ti_(3)C_(2)T_(x)into Li_(2)TiO_(3) layer occurs at a low temperature of 500℃,avoiding the phase deterioration of LiCoO_(2).The thin Li_(2)TiO_(3) layer is Li^(+)conducting and electrochemically stable,thereby preventing the interfacial decomposition of sulfide electrolytes induced by LiCoO_(2) at high voltages and facilitating Li+transport at the interface.Moreover,Li_(2)TiO_(3) can stabilize the layer structure of LiCoO_(2) at high voltages.Consequently,the sulfide-based ASSLB using LiCoO_(2)@Li_(2)TiO_(3) cathode can operate stably at a high voltage of up to 4.5 V(vs.Li+/Li),delivering an outstanding initial specific discharge capacity of 138.8 m Ah/g with a high capacity retention of 86.2% after 100 cycles at 0.2 C.The in-situ transformation strategy may also apply to other MXenes,offering a general approach for constructing other advanced lithiated coatings for oxide cathodes.
基金supported by the National Key R&D Program of China(2021YFD1200804 and 2018YFD0901201)the Strategic Priority Research Program of the Chinese Academy of Sciences(Precision Seed Design and Breeding)(XDA24010206)。
文摘Fishes are the largest group of vertebrates,representing more than half of all vertebrate species on Earth.Important aquaculture species,such as Atlantic salmon,cod,and large yellow croaker,contribute to over 16%of the global seafood supply for human consumption(Food and Agriculture Organization of the United Nations,2020).Zebrafish(Danio rerio),medaka(Oryzias latipes),threespined stickleback(Gasterosteus aculeatus),and other fish species are important model organisms in life science research.
基金National Natural Science Foundation of China,Grant/Award Number:81770252,82030014,82271606 and U22A20267Binjiang Institute of Zhejiang University,Grant/Award Number:ZY202205SMKY001Key Program of Major Science and Technology Projects in Zhejiang Province,Grant/Award Number:2021C03097 and 2022C03063。
文摘Background:Calcific aortic valve stenosis(CAVS)is one of the most challenging heart diseases in clinical with rapidly increasing prevalence.However,study of the mecha-nism and treatment of CAVS is hampered by the lack of suitable,robust and efficient models that develop hemodynamically significant stenosis and typical calcium deposi-tion.Here,we aim to establish a mouse model to mimic the development and features of CAVS.Methods:The model was established via aortic valve wire injury(AVWI)combined with vitamin D subcutaneous injected in wild type C57/BL6 mice.Serial transthoracic echocardiography was applied to evaluate aortic jet peak velocity and mean gradi-ent.Histopathological specimens were collected and examined in respect of valve thickening,calcium deposition,collagen accumulation,osteogenic differentiation and inflammation.Results:Serial transthoracic echocardiography revealed that aortic jet peak velocity and mean gradient increased from 7 days post model establishment in a time depend-ent manner and tended to be stable at 28 days.Compared with the sham group,sim-ple AVWI or the vitamin D group,the hybrid model group showed typical pathological features of CAVS,including hemodynamic alterations,increased aortic valve thicken-ing,calcium deposition,collagen accumulation at 28 days.In addition,osteogenic dif-ferentiation,fibrosis and inflammation,which play critical roles in the development of CAVS,were observed in the hybrid model.Conclusions:We established a novel mouse model of CAVS that could be induced efficiently,robustly and economically,and without genetic intervention.It provides a fast track to explore the underlying mechanisms of CAVS and to identify more effec-tive pharmacological targets.
基金supported by the Knowledge Innovation Program of Wuhan-Basic Research(Nos.2023020201010084,2022010801010134)the National Key Research and Development Program of China(No.2019YFA0307700)the National Natural Science Foundation of China(Nos.12274418,22273116,12074389,11974381,22363011).
文摘A liquid-microjet(LJ)linear time-of-flight(TOF)mass spectrometer,coupled with a femtosecond laser ionization source,has been designed for direct measurements of mass spectra of liquid aqueous solutions.Two main features of our designed spectrometer involve the coupling of a liquid microjet nozzle to a conventional ion optics and the application of femtosecond pulses for mass spectral ionization.The detailed design,construction,and simulation of this new spectrometer are presented.More importantly,we combined the experimental tests with the simulated electric fields and ion trajectories to investigate the performance of the designed spectrometer,especially the kind of disturbances of the nozzle electric field on the conventional ion optics.In our current design,the optimal E/R(E:extractor,R:repeller)electrode voltage ratio was found to be∼0.71 when the voltages on the R,E and G(ground)electrodes were set to be 1500,1060 and 0 V,respectively,whilst the voltage on the N nozzle electrode was required to be around 1250 V.The capability of the designed spectrometer has been demonstrated by recording the simulated mass spectra of the water,benzene and cytidine with their mass/charge ratios of 18,76 and 243,respectively.This work shall be helpful for the development of new all-liquid-phase mass spectral technology to be employed in the diagnosis of diseases by the mass analysis of human body fluids.
基金funded by the Digital workshop dynamic Reconstruction modeling Technology(Grant No.2020YFB1710701)the National Natural Science Foundation of China(Grant No.52172099)the Provincial Joint Fund of Shaanxi(Grant No.2021JLM-28).
文摘Ionic polymer-metal composites(IPMCs)constitute a new type of artificial muscle material that is commonly used in bionic soft robots and medical devices because of its small driving voltage and considerable deformation.However,IPMCs are limited by performance issues such as low output force and small operating time away from water.Silicon dioxide sulfonated graphene(SiO_(2)-SGO)particles are often used to improve the performance of polymer membranes because of their hydrophilicity and high chemical stability.Reported here is the addition of SiO_(2)-SGO particles prepared by in situ hydrolysis to perfluorosulfonic acid in order to improve the IPMC properties.Also,a predictive model was constructed based on a backpropagation neural network,with the SiO_(2)-SGO doping amount and the IPMC excitation voltage in the input layer and the driving displacement in the output layer.The results show that the IPMC prepared with 1.0 wt.%doping content performed the best,with a maximum output displacement of 47.7 mm.The correlation coefficient(R2)was 0.9842 and the mean square error was 0.00037073,which show that the predictive model has high predictive accuracy and is suitable for predicting the performance of the SiO_(2)-SGO-modified IPMC.
