Global demand for farm animals and their meat products i.e.,pork,chicken and other livestock meat,is steadily incresing.With the ongoing life science research and the rapid development of biotechnology,it is a great o...Global demand for farm animals and their meat products i.e.,pork,chicken and other livestock meat,is steadily incresing.With the ongoing life science research and the rapid development of biotechnology,it is a great opportunity to develop advanced molecular breeding markers to efficiently improve animal meat production traits.Hippo is an important study subject because of its crucial role in the regulation of organ size.In recent years,with the increase of research on Hippo signaling pathway,the integrative application of multi-omics technologies such as genomics,transcriptomics,proteomics,and metabolomics can help promote the in-depth involvement of Hippo signaling pathway in skeletal muscle development research.The Hippo signaling pathway plays a key role in many biological events,including cell division,cell migration,cell proliferation,cell differentiation,cell apoptosis,as well as cell adhesion,cell polarity,homeostasis,maintenance of the face of mechanical overload,etc.Its influence on the development of skeletal muscle has important research value for enhancing the efficiency of animal husbandry production.In this study,we traced the origin of the Hippo pathway,comprehensively sorted out all the functional factors found in the pathway,deeply analyzed the molecular mechanism of its function,and classified it from a novel perspective based on its main functional domain and mode of action.Our aim is to systematically explore its regulatory role throughout skeletal muscle development.We specifically focus on the Hippo signaling pathway in embryonic stem cell development,muscle satellite cell fate determination,myogenesis,skeletal muscle meat production and organ size regulation,muscle hypertrophy and atrophy,muscle fiber formation and its transformation between different types,and cardiomyocytes.The roles in proliferation and regeneration are methodically summarized and analyzed comprehensively.The summary and prospect of the Hippo signaling pathway within this article will provide ideas for further improving meat production and muscle deposition and developing new molecular breeding technologies for livestock and poultry,which will be helpful for the development of animal molecular breeding.展开更多
As a sister compound of PbTe, SnTe possesses the environmentally friendly elements. However, the pristine SnTe compounds suffer from the high carrier concentration, the large valence band offset between the L and Σpo...As a sister compound of PbTe, SnTe possesses the environmentally friendly elements. However, the pristine SnTe compounds suffer from the high carrier concentration, the large valence band offset between the L and Σpositions and high thermal conductivity. Using high-pressure and high-temperature technology, we synthesized the pristine SnTe samples at different pressures and systemically investigated their thermoelectric properties.High pressure induces rich microstructures, including the high-density dislocations and lattice distortions, which serve as the strong phonon scattering centers, thereby reducing the lattice thermal conductivity. For the electrical properties, pressure reduces the harmful high carrier concentration, due to the depression of Sn vacancies.Moreover, pressure induces the valence band convergence, reducing the energy separation between the L and Σpositions. The band convergence and suppressed carrier concentration increase the Seebeck coefficient. Thus, the power factors of pressure-sintered compounds do not deteriorate significantly under the condition of decreasing electrical conductivity. Ultimately, for a pristine SnTe compound synthesized at 5 GPa, a higher ZT value of 0.51 is achieved at 750 K, representing a 140% improvement compared to the value of 0.21 obtained using SPS. Therefore, the high-pressure and high-temperature technology is demonstrated as an effectively approach to optimize thermoelectric performance.展开更多
High pressure and high temperature(HPHT)technology,as an extreme physical condition,plays an important role in regulating the properties of materials,having the advantages of enhancing doping efficiency,refining grain...High pressure and high temperature(HPHT)technology,as an extreme physical condition,plays an important role in regulating the properties of materials,having the advantages of enhancing doping efficiency,refining grain size,and manufacturing defects,therefore it is quite necessary to study the effectiveness on tuning thermoelectric properties.Elemental telluride,a potential candidate for thermoelectric materials,has the poor doping efficiency and high resistivity,which become an obstacle for practical applications.Here,we report the realization of a dual optimization of electrical behaviors and thermal conductivity through HPHT method combining with the introduction of black phosphorus.The results show the maximum zT of 0.65 and an average zT of 0.42(300 K–610 K),which are increased by 55%and 68%in the synthesis pressure regulation system,respectively.This study clarifies that the HPHT method has significant advantages in modulating the thermoelectric parameters,providing a reference for seeking high performance thermoelectric materials.展开更多
Objective:To investigate the clinical efficacy of acupuncture combined with emotional intervention in patients with post-stroke depression(PSD).Methods:A total of 100 patients with PSD who met the inclusion criteria w...Objective:To investigate the clinical efficacy of acupuncture combined with emotional intervention in patients with post-stroke depression(PSD).Methods:A total of 100 patients with PSD who met the inclusion criteria were randomly divided into an experimental group(50 cases)and a control group(50 cases)using the random number table method,and the enrollment was in order of admission time.The control group used conventional treatment of oral antidepressant Deanxit tablets(0.5 mg flupenthixol+10 mg melitracen)with the dose appropriately adjusted according to the patient’s medication effect,and modern rehabilitation treatment given selectively according to the patient’s condition.The experimental group had similar treatment as the control group with the addition of traditional Chinese medicine(TCM)acupuncture combined with emotional intervention.The application effects of both groups before and after treatment were verified using the Hamilton Depression Rating Scale(Ham-D),National Institutes of Health Stroke Scale(NIHSS),and Activities of Daily Living(ADL),serotonin levels were measured,and statistical analyses were carried out.Results:The total effective rate of patients in the experimental group was significantly higher than that in the control group,and the Ham-D score,NIHSS score,ADL score,and serotonin level after treatment were significantly higher than those in the control group,and the difference between the two groups was statistically significant(P<0.05).Conclusion:For patients with PSD,adding TCM acupuncture with emotional intervention on top of conventional treatment significantly improve the clinical efficacy and better improve the daily life ability of patients.展开更多
Brain-derived neurotrophic factor is associated with the insulin signaling pathway and glucose me- tabolism. We hypothesized that expression of brain-derived neurotrophic factor and its receptor may be involved in glu...Brain-derived neurotrophic factor is associated with the insulin signaling pathway and glucose me- tabolism. We hypothesized that expression of brain-derived neurotrophic factor and its receptor may be involved in glucose intolerance following ischemic stress. To verify this hypothesis, this study aimed to observe the changes in brain-derived neurotrophic factor and tyrosine kinase B receptor expression in glucose metabolism-associated regions following cerebral ischemic stress in mice. At day 1 after middle cerebral artery occlusion, the expression levels of brain-derived neurotrophic factor were significantly decreased in the ischemic cortex, hypothalamus, liver, skeletal muscle, and pancreas. The expression levels of tyrosine kinase B receptor were decreased in the hypothalamus and liver, and increased in the skeletal muscle and pancreas, but remained unchanged in the cortex Intrahypothalamic administration of brain-derived neurotrophic factor (40 ng) suppressed the de- crease in insulin receptor and tyrosine-phosphorylated insulin receptor expression in the liver and skeletal muscle, and inhibited the overexpression of gluconeogenesis-associated phosphoenolpy- ruvate carboxykinase and glucose-6-phosphatase in the liver of cerebral ischemic mice. However, serum insulin levels remained unchanged. Our experimental findings indicate that brain-derived neurotrophic factor can promote glucose metabolism, reduce gluconeogenesis, and decrease blood glucose levels after cerebral ischemic stress. The low expression of brain-derived neurotrophic factor following cerebral ischemia may be involved in the development of glucose intolerance.展开更多
This study investigated the important factors that affect the operating parameters of thermally regenerative ammoniabased batteries(TRABs),including the metal electrode type,membrane type,electrode surface area,electr...This study investigated the important factors that affect the operating parameters of thermally regenerative ammoniabased batteries(TRABs),including the metal electrode type,membrane type,electrode surface area,electrode distance,electrolyte concentration,and ammonia concentration.The experimental results showed that the maximum power density of TRABs with a Cu electrode was 40.0 W·m^(2),which was considerably higher than that with Ni(0.34 W·m^(2))and Co(0.14 W·m^(2))electrodes.TRABs with an anion exchange membrane had a 28.6%higher maximum power density than those with a cation exchange membrane.An increased electrode surface resulted in an increased maximum power but a decreased maximum power density.Within a certain range,TRAB performance was enhanced with decreased electrode distance and increased electrolyte concentration.An increased ammonia concentration resulted in enhanced ammonia transfer and improved the TRAB performance.展开更多
This article focuses on the first aspect of the album of deep learning: the deep convolutional method. The traditional matching point extraction algorithm typically uses manually designed feature descriptors and the s...This article focuses on the first aspect of the album of deep learning: the deep convolutional method. The traditional matching point extraction algorithm typically uses manually designed feature descriptors and the shortest distance between them to match as the matching criterion. The matching result can easily fall into a local extreme value, which causes missing of the partial matching point. Targeting this problem, we introduce a two-channel deep convolutional neural network based on spatial scale convolution, which performs matching pattern learning between images to realize satellite image matching based on a deep convolutional neural network. The experimental results show that the method can extract the richer matching points in the case of heterogeneous, multi-temporal and multi-resolution satellite images, compared with the traditional matching method. In addition, the accuracy of the final matching results can be maintained at above 90%.展开更多
In order to investigate the influence of aluminum vapor on the breakdown performance of air,this paper makes a study of the dielectric breakdown characteristics of Al-air mixture in the temperature range of 300-5000 K...In order to investigate the influence of aluminum vapor on the breakdown performance of air,this paper makes a study of the dielectric breakdown characteristics of Al-air mixture in the temperature range of 300-5000 K at atmospheric pressure.A Boltzmann analysis method is used to deal with the electron energy distribution function(EEDF),the reduced ionization coefficients(α/N),the reduced attachment coefficients(η/N)and the critical reduced breakdown strength((E/N)cr)so as to explore the influence of temperature and mixing ratio on the dielectric breakdown properties.In the temperature range of 300-2000 K,the property of the mixture is mainly determined by the mixing proportion of aluminum vapor because the composition of particles remains unchanged.In the temperature range of 2000-2500 K,the decomposition of Al2O_(2)leads to the increase of aluminum oxides and NO,and a rise in the percentage of highenergy electrons as well as the increment ofα/N.Also,the joint action of O_(2)and NO makesη/N increase first and then decrease,and(E/N)crgoes down to a smaller temperature range.An increase in the proportion of aluminum vapor causes(E/N)crto decrease in the low-temperature region and to increase in the high-temperature region,which will reduce the transition between these two temperature regions.展开更多
By using a surface air temperature index (SATI) averaged over the eastern Tibetan Plateau (TP), investigation is conducted on the short-term climate variation associated with the interannual air warming (or cool...By using a surface air temperature index (SATI) averaged over the eastern Tibetan Plateau (TP), investigation is conducted on the short-term climate variation associated with the interannual air warming (or cooling) over the TP in each summer month. Evidence suggests that the SATI is associated with a consistent teleconnection pattern extending from the TP to central-western Asia and southeastern Europe. Associated rainfall changes include, for a warming case, a drought in northern India in May and June, and a stronger mei-yu front in June. The latter is due to an intensified upper-level northeasterly in eastern China and a wetter and warmer condition over the eastern TP. In the East Asian regions, the time-space distributions of the correlation patterns between SATI and rainfall are more complex and exhibit large differences from month to month. Some studies have revealed a close relationship between the anomalous heating over the TP and the rainfall anomaly along the Yangtze River valley appearing in the summer on a seasonal mean time-scale, whereas in the present study, this relationship only appears in June and the signal's significance becomes weaker after the long-term trend in the data was excluded. Close correlations between SATI and the convection activity and SST also occur in the western Pacific in July and August: A zonally-elongated warm tone in the SST in the northwestern Pacific seems to be a passive response of the associated circulation related to a warm SATI. The SATI-associated teleconnection pattern provides a scenario consistently linking the broad summer rainfall anomalies in Europe, central-western Asia, India, and East Asia.展开更多
We present numerical results of a one-dimensional spin–orbit coupled Bose–Einstein condensate expanding in a speckle disorder potential by employing the Gross–Pitaevskii equation.Localization properties of a spin–...We present numerical results of a one-dimensional spin–orbit coupled Bose–Einstein condensate expanding in a speckle disorder potential by employing the Gross–Pitaevskii equation.Localization properties of a spin–orbit coupled Bose–Einstein condensate in zero-momentum phase,magnetic phase and stripe phase are studied.It is found that the localizing behavior in the zero-momentum phase is similar to the normal Bose–Einstein condensate.Moreover,in both magnetic phase and stripe phase,the localization length changes non-monotonically as the fitting interval increases.In magnetic phases,the Bose–Einstein condensate will experience spin relaxation in disorder potential.展开更多
In this paper,an efficient technique for removing strip noise from remote sensing images is proposed in order to better retain image details.Firstly,the remote sensing image with strip noise is decomposed by wavelet t...In this paper,an efficient technique for removing strip noise from remote sensing images is proposed in order to better retain image details.Firstly,the remote sensing image with strip noise is decomposed by wavelet technology;Secondly,two variational models are constructed,stripe preserve variation model and a destriping variation model.In order to efficiently separate the detail information in the low level high-frequency component,the stripe preserve variation model eliminates the detail information from the low level high-frequency component(including strip noise)while maintaining the strip noise(including strip noise).In order to successfully save the details in the high level high-frequency component,the destriping variation model eliminates the strip noise in the high level high-frequency component(including the strip noise).Finally,wavelet reconstruction is used to get the denoised image.It is clear from a comparison with previous approaches that the suggested method not only successfully removes strip noise but also preserves image details.展开更多
Using Embedded-atom-method (EAM) potential, we have performed in detail molecular dynamics studies on a Fe adatom adsorption and diffusion dynamics on three low miller index surfaces, Fe (110), Fe (001), and Fe (111)....Using Embedded-atom-method (EAM) potential, we have performed in detail molecular dynamics studies on a Fe adatom adsorption and diffusion dynamics on three low miller index surfaces, Fe (110), Fe (001), and Fe (111). Our results present that adatom adsorption energies and diffusion barriers on these surfaces have similar monotonic trend: adsorption energies, Ea(110) Ea(001) Ea(111), diffusion barriers, Ed(110) Ed(001) Ed(111). On the Fe (110) surface, adatom simple jump is the main diffusion mechanism with relatively low energy barrier;nevertheless, adatoms exchange with surface atoms play a dominant role in surface diffusion on the Fe (001).展开更多
With the continuous economic growth,human resources service industry also plays an important role in the economic development.In order to explore the development of human resources service industry in Xinxiang,based o...With the continuous economic growth,human resources service industry also plays an important role in the economic development.In order to explore the development of human resources service industry in Xinxiang,based on a survey of more than 50 enterprises and organizations in Xinxiang,Xinxiang’s human resources service industry has a bright future,however,there are still some problems in the aspects of enterprise scale,personnel skills and agglomeration management.Therefore,different countermeasures are put forward for different roles to solve the development obstacles and promote the development of industry agglomeration,building a new type of human resources to serve the ecological industry chain.展开更多
Additive manufacturing technology,by manipulating and emulating inherent multiscale,multi-material,and multifunctional structures found in nature,has created new opportunities for constructing heterogeneous structures...Additive manufacturing technology,by manipulating and emulating inherent multiscale,multi-material,and multifunctional structures found in nature,has created new opportunities for constructing heterogeneous structures associated with special properties and achieving ultra-high mechanical performance and reliability in ceramic composite materials.In this study,we have developed an innovative fabrication method designated as coaxial 3D printing for the synchronous construction of two constituents into ceramic composites with a tooth enamel biomimetic microstructure.Herein,the stiff silicate and flexible epoxy served as a strengthening bridge and toughening layer,respectively.The method differed from the traditional approach of randomly dispersing reinforcing components within a ceramic matrix.It allowed for the direct creation of an internally effective three-dimensional reinforcement network structure in ceramic composites.This process facilitated synergistic deformation and simultaneous enhancement of multiple materials and hierarchical structures.Owing to the uniform distribution of internal stress and effective block of microcrack propagation,the biomimetically structured silicate/epoxy ceramic composite has demonstrated much significant enhancement in mechanical properties,includingcompressive strength(48.8±3.12MPa),flexuralstrength(10.39±1.23MPa),andflexuraltoughness(218.7±54.6kJ/m^(3)),which was 0.5,2.1,and 47.5 times as high as those of the intrinsic brittle silicate ceramics,respectively.In-situ characterization and multiscale finite element simulation of microstructural evolution during three-point bending deformation further validated multiple-step features of the fracture process(silicate bridge fracture,interface detachment,epoxy extraction,and rupture),which benefited from interpenetrating structural features achieved by coaxial printing to accomplish with the complex propagating routines of the crack deflection in silicate ceramic composites.This coaxial 3D printing method paves the way for tailored toughening-strengthening designs for other brittle engineering ceramic materials.展开更多
The tribological properties of self-lubricating composites are influenced by many variables and complex mechanisms.Data-driven methods,including machine learning(ML)algorithms,can yield a better comprehensive understa...The tribological properties of self-lubricating composites are influenced by many variables and complex mechanisms.Data-driven methods,including machine learning(ML)algorithms,can yield a better comprehensive understanding of complex problems under the influence of multiple parameters,typically for how tribological performances and material properties correlate.Correlation of friction coefficients and wear rates of copper/aluminum-graphite(Cu/Al-graphite)self-lubricating composites with their inherent material properties(composition,lubricant content,particle size,processing process,and interfacial bonding strength)and the variables related to the testing method(normal load,sliding speed,and sliding distance)were analyzed using traditional approaches,followed by modeling and prediction of tribological properties through five different ML algorithms,namely support vector machine(SVM),K-Nearest neighbor(KNN),random forest(RF),eXtreme gradient boosting(XGBoost),and least-squares boosting(LSBoost),based on the tribology experimental data.Results demonstrated that ML models could satisfactorily predict friction coefficient and wear rate from the material properties and testing method variables data.Herein,the LSBoost model based on the integrated learning algorithm presented the best prediction performance for friction coefficients and wear rates,with R^(2) of 0.9219 and 0.9243,respectively.Feature importance analysis also revealed that the content of graphite and the hardness of the matrix have the greatest influence on the friction coefficients,and the normal load,the content of graphite,and the hardness of the matrix influence the wear rates the most.展开更多
The felsic volcanogenic tuffs named"green-bean rocks"(GBRs),characterized by a green or yellowish green color,are widely distributed in the western Yangtze platform and have a high lithium content(286-957 pp...The felsic volcanogenic tuffs named"green-bean rocks"(GBRs),characterized by a green or yellowish green color,are widely distributed in the western Yangtze platform and have a high lithium content(286-957 ppm).This paper studies the ages,origin and tectonic setting of the GBRs in the Sichuan basin on the western margin of the Yangtze platform through the whole-rock geochemistry and zircon trace elements by using U-Pb dating and Hf-O isotopes.The GBR samples from the Quxian and Beibei sections yielded zircon U-Pb ages of 245.5±1.8 Ma and 244.8±2.2 Ma.These samples can be used as the isochronous stratigraphic marker of the Early-Middle Triassic boundary(EMTB)for regional correlation.The whole-rock and zircon geochemistry,and zircon Hf-O isotopes exhibited S-type geochemical affinities with high positiveδ^(18)0 values(9.28‰-11.98‰),low negativeε_(Hf)(t)values(-13.87 to-6.79),and T_(DM)^(2)ages of 2150-1703 Ma,indicating that the lithium-rich GBRs were generated by the remelting of the pre-existing ancient Paleoproterozoic layer without mantle source contamination in the arcrelated/orogenic tectonic setting.The results of this study demonstrate that the lithium-rich GBRs in the western Yangtze platform were derived from arc volcanic eruptions along the Sanjiang orogen,triggered by the closure of the eastern Paleo-Tethys Ocean and the syn-collision between the continental Indochina and Yangtze blocks at ca.247 Ma.This was marked by a major shift from I-type magmas with intermediateε_(Hf)(t)values to S-type magmas with low negativeε_(Hf)(t)values.Collectively,our results provide new insights into the origin of the GBRs and decodes the closure of the eastern Paleo-Tethys.展开更多
Thermally regenerative batteries(TRBs) are promising for harvesting low-grade waste heat into electrical power. However, the ammonia crossover from anode to cathode causes self-discharge and then leads to the decay of...Thermally regenerative batteries(TRBs) are promising for harvesting low-grade waste heat into electrical power. However, the ammonia crossover from anode to cathode causes self-discharge and then leads to the decay of capacity. To alleviate the ammonia crossover and improve electricity generation, a stable graphene oxide(GO) modified anion exchange membrane(AEM) was proposed. Compared with the original AEM, the GO modified AEM with a 39.5% lower ammonia permeability induces a 24.3% higher maximal power output and 20.2% higher energy density in TRBs. Together with the visualization result,it was demonstrated the ammonia crossover was effectively alleviated by GO modifying the AEM not at a cost of the reduced battery performance, indicating the promising application in future TRBs.展开更多
Objective:To investigate the differences in small intestinal toxicity and taxonomic composition,diversity,and functional pathways of gut microbiome and metabolome after different radiotherapies in mouse colorectal can...Objective:To investigate the differences in small intestinal toxicity and taxonomic composition,diversity,and functional pathways of gut microbiome and metabolome after different radiotherapies in mouse colorectal cancer(CRC)model.Methods:Azoxymethane/dextran sodium sulfate(AOM/DSS)-induced mouse CRC model was treated with single pulse FLASH-RT(dose rate 100 Gy/s)or CONV-RT(dose rate 2 Gy/min)at whole abdomen.At 12 d after radiotherapy,sections of small intestinal tract tissue were dissected for hematoxylin and eosin(HE)staining and the fresh feces were collected for 16S ribosomal RNA(rRNA)microbiome sequencing and liquid chromatography and mass spectrometry(LC-MS)metabolomics sequencing to assess changes in the gut microbiota and metabolites.Microbial high-throughput 16S rRNA data was analyzed with QIIME2 and LEfSe softwares.ProteoWizard,XCMS and Ropls softwares were used for LC-MS analysis.Results:HE staining showed that FLASH-RT maintained small intestinal integrity and reduced the radiotherapyinduced injury.Sequencing analysis of gut fecal microbiome showed that phylum Bacteroidetes and genera Prevotella and Lactobacillus of microbial community were increased after FLASH-RT.Metabolomics sequencing analysis revealed that the metabolites after FLASH-RT were enriched in amino acid metabolism,while cholesterol metabolism was top enriched after CONV-RT.Conclusions:FLASH-RT significantly mitigates the small intestine tissue damage compared with CONV-RT.FLASHRT and CONV-RT have different impact on gut microbiota and its metabolites.Our results provide a theoretical basis for the early evaluation,prediction and individualized treatment of the irradiation effect after novel FLASHRT on tumors through the evaluation of intestinal microbiota and metabolites.展开更多
Mn-based Prussian blue analogues(Mn-PBAs),featuring a three-dimensional(3D)metal-organic framework and multiple redox couples,have gained wide interests in Zn-ion batteries(ZIBs).However,owing to the Jahn-Teller disto...Mn-based Prussian blue analogues(Mn-PBAs),featuring a three-dimensional(3D)metal-organic framework and multiple redox couples,have gained wide interests in Zn-ion batteries(ZIBs).However,owing to the Jahn-Teller distortion and disproportionation reaction of Mn^(3+),these materials suffer from poor electrochemical performances and inferior structural stability.Herein,we prepare a typical high-entropy Prussian blue analogue(HE-PBA)with increased configuration entropy through integrating five transition metal elements of Mn,Co,Ni,Fe and Cu into the nitrogen-coordinated-M-lattice sites.Consequently,the HE-PBA presents enhanced uptake of Zn^(2+)with 80 mAh·g^(−1)compared to those medium-entropy PBAs,low-entropy PBAs and conventional PBAs,which can be assigned to“cocktail”effect of multiple transition metal active redox couples.Furthermore,a phase transition process from monoclinic phase to rhombohedral phase occurs in HE-PBA cathode,resulting in a stable structure of MN6(M=Mn,Co,Fe,Ni,Cu)and ZnN4 co-linked to FeC6 through the cyanide ligands.Additionally,the advantages of entropy-driven stability are also confirmed by the calculated reduction energy and the density of states between HE-PBA and KMn[Fe(CN)6](KMnHCF).This work not only presents a high-performance HE-PBA cathode in ZIBs,but also introduces a novel concept of high entropy benefiting for designing advanced materials.展开更多
High-entropy carbides are a nascent group of ceramics that are promising for high-temperature applications due to the combination of good stability,high hardness(H),high strength,and superior creep resistance that the...High-entropy carbides are a nascent group of ceramics that are promising for high-temperature applications due to the combination of good stability,high hardness(H),high strength,and superior creep resistance that they display.Due to high melting points and low lattice diffusion coefficients,however,the high-entropy carbides are usually difficult to consolidate to a nearly full density.To cope with this challenge,herein,binary carbides including TiC,V_(8)C_(7),NbC,Mo_(2)C,and WC with different carbon stoichiometry were used to prepare dense high-entropy(TiVNbMoW)C_(4.375),and the influence of carbon vacancy on formation ability and mechanical properties of carbon-deficient high-entropy(TiVNbMoW)C_(4.375) were investigated.Intriguingly,although the starting binary carbides have different crystal structures and carbon stoichiometry,the as-prepared high-entropy material showed a rock-salt structure with a relatively high density(98.1%)and good mechanical properties with hardness of 19.4±0.4 GPa and fracture toughness(KIC)of 4.02 MPa·m^(1/2).More importantly,the high-entropy(TiVNbMoW)C_(4.375) exhibited low coefficient of friction(COF)at room temperature(RT)and 800℃.Wear rate(W)gradually increased with the temperature rising,which were attributed to the formation of low-hardness oxidation films at high temperatures to aggravate wear.At 800℃,lubricating films formed from sufficient oxidation products of V_(2)O_(5) and MoO_(3) effectively improved tribological behavior of the high-entropy(TiVNbMoW)C_(4.375).Wear mechanisms were mainly abrasive wear resulting from grain pullout and brittle fracture as well as oxidation wear generated from high-temperature reactions.These results are useful as valuable guidance and reference to the synthesis of high-entropy ceramics(HECs)for sliding parts under high-temperature serving conditions.展开更多
基金supported by the National Natural Science Foundation of China(31830090)the High-level Talent Project of Shihezi University,China(2022ZK022)the Agricultural Science and Technology Innovation Program,Chinese Academy of Agricultural Sciences(CAAS-ZDRW202006).
文摘Global demand for farm animals and their meat products i.e.,pork,chicken and other livestock meat,is steadily incresing.With the ongoing life science research and the rapid development of biotechnology,it is a great opportunity to develop advanced molecular breeding markers to efficiently improve animal meat production traits.Hippo is an important study subject because of its crucial role in the regulation of organ size.In recent years,with the increase of research on Hippo signaling pathway,the integrative application of multi-omics technologies such as genomics,transcriptomics,proteomics,and metabolomics can help promote the in-depth involvement of Hippo signaling pathway in skeletal muscle development research.The Hippo signaling pathway plays a key role in many biological events,including cell division,cell migration,cell proliferation,cell differentiation,cell apoptosis,as well as cell adhesion,cell polarity,homeostasis,maintenance of the face of mechanical overload,etc.Its influence on the development of skeletal muscle has important research value for enhancing the efficiency of animal husbandry production.In this study,we traced the origin of the Hippo pathway,comprehensively sorted out all the functional factors found in the pathway,deeply analyzed the molecular mechanism of its function,and classified it from a novel perspective based on its main functional domain and mode of action.Our aim is to systematically explore its regulatory role throughout skeletal muscle development.We specifically focus on the Hippo signaling pathway in embryonic stem cell development,muscle satellite cell fate determination,myogenesis,skeletal muscle meat production and organ size regulation,muscle hypertrophy and atrophy,muscle fiber formation and its transformation between different types,and cardiomyocytes.The roles in proliferation and regeneration are methodically summarized and analyzed comprehensively.The summary and prospect of the Hippo signaling pathway within this article will provide ideas for further improving meat production and muscle deposition and developing new molecular breeding technologies for livestock and poultry,which will be helpful for the development of animal molecular breeding.
基金supported by the National Natural Science Foundation of China (Grant Nos. 12374012, 11974208, 52172212, and 52002217)Shandong Provincial Natural Science Foundation (Grant Nos. ZR2023JQ001, ZR2020YQ05, and 2019KJJ020)financial support from the Program of Distinguished Expert of Taishan Scholar (Grant No. tstp20221124)。
文摘As a sister compound of PbTe, SnTe possesses the environmentally friendly elements. However, the pristine SnTe compounds suffer from the high carrier concentration, the large valence band offset between the L and Σpositions and high thermal conductivity. Using high-pressure and high-temperature technology, we synthesized the pristine SnTe samples at different pressures and systemically investigated their thermoelectric properties.High pressure induces rich microstructures, including the high-density dislocations and lattice distortions, which serve as the strong phonon scattering centers, thereby reducing the lattice thermal conductivity. For the electrical properties, pressure reduces the harmful high carrier concentration, due to the depression of Sn vacancies.Moreover, pressure induces the valence band convergence, reducing the energy separation between the L and Σpositions. The band convergence and suppressed carrier concentration increase the Seebeck coefficient. Thus, the power factors of pressure-sintered compounds do not deteriorate significantly under the condition of decreasing electrical conductivity. Ultimately, for a pristine SnTe compound synthesized at 5 GPa, a higher ZT value of 0.51 is achieved at 750 K, representing a 140% improvement compared to the value of 0.21 obtained using SPS. Therefore, the high-pressure and high-temperature technology is demonstrated as an effectively approach to optimize thermoelectric performance.
基金Project supported by the National Natural Science Foundation of China(Grant Nos.11804185,11974208,52172212,52102335,and 52002217)the Natural Science Foundation of Shandong Province,China(Grant Nos.ZR2020YQ05,ZR2019MA054,2019KJJ020,ZR2021YQ03,and 2022KJA043)。
文摘High pressure and high temperature(HPHT)technology,as an extreme physical condition,plays an important role in regulating the properties of materials,having the advantages of enhancing doping efficiency,refining grain size,and manufacturing defects,therefore it is quite necessary to study the effectiveness on tuning thermoelectric properties.Elemental telluride,a potential candidate for thermoelectric materials,has the poor doping efficiency and high resistivity,which become an obstacle for practical applications.Here,we report the realization of a dual optimization of electrical behaviors and thermal conductivity through HPHT method combining with the introduction of black phosphorus.The results show the maximum zT of 0.65 and an average zT of 0.42(300 K–610 K),which are increased by 55%and 68%in the synthesis pressure regulation system,respectively.This study clarifies that the HPHT method has significant advantages in modulating the thermoelectric parameters,providing a reference for seeking high performance thermoelectric materials.
基金The Shandong Traditional Chinese Medicine Science and Technology Development Program 2020Q132。
文摘Objective:To investigate the clinical efficacy of acupuncture combined with emotional intervention in patients with post-stroke depression(PSD).Methods:A total of 100 patients with PSD who met the inclusion criteria were randomly divided into an experimental group(50 cases)and a control group(50 cases)using the random number table method,and the enrollment was in order of admission time.The control group used conventional treatment of oral antidepressant Deanxit tablets(0.5 mg flupenthixol+10 mg melitracen)with the dose appropriately adjusted according to the patient’s medication effect,and modern rehabilitation treatment given selectively according to the patient’s condition.The experimental group had similar treatment as the control group with the addition of traditional Chinese medicine(TCM)acupuncture combined with emotional intervention.The application effects of both groups before and after treatment were verified using the Hamilton Depression Rating Scale(Ham-D),National Institutes of Health Stroke Scale(NIHSS),and Activities of Daily Living(ADL),serotonin levels were measured,and statistical analyses were carried out.Results:The total effective rate of patients in the experimental group was significantly higher than that in the control group,and the Ham-D score,NIHSS score,ADL score,and serotonin level after treatment were significantly higher than those in the control group,and the difference between the two groups was statistically significant(P<0.05).Conclusion:For patients with PSD,adding TCM acupuncture with emotional intervention on top of conventional treatment significantly improve the clinical efficacy and better improve the daily life ability of patients.
基金supported by the Talent Foundation of the Affiliated Hospital of Guangxi Medical College in China,No.08026Youth Researcher Foundation of Guangxi Medical College in China,No.08012Scientific Research Foundation from Science and Technology Bureau of Shanghai City,No.074119048
文摘Brain-derived neurotrophic factor is associated with the insulin signaling pathway and glucose me- tabolism. We hypothesized that expression of brain-derived neurotrophic factor and its receptor may be involved in glucose intolerance following ischemic stress. To verify this hypothesis, this study aimed to observe the changes in brain-derived neurotrophic factor and tyrosine kinase B receptor expression in glucose metabolism-associated regions following cerebral ischemic stress in mice. At day 1 after middle cerebral artery occlusion, the expression levels of brain-derived neurotrophic factor were significantly decreased in the ischemic cortex, hypothalamus, liver, skeletal muscle, and pancreas. The expression levels of tyrosine kinase B receptor were decreased in the hypothalamus and liver, and increased in the skeletal muscle and pancreas, but remained unchanged in the cortex Intrahypothalamic administration of brain-derived neurotrophic factor (40 ng) suppressed the de- crease in insulin receptor and tyrosine-phosphorylated insulin receptor expression in the liver and skeletal muscle, and inhibited the overexpression of gluconeogenesis-associated phosphoenolpy- ruvate carboxykinase and glucose-6-phosphatase in the liver of cerebral ischemic mice. However, serum insulin levels remained unchanged. Our experimental findings indicate that brain-derived neurotrophic factor can promote glucose metabolism, reduce gluconeogenesis, and decrease blood glucose levels after cerebral ischemic stress. The low expression of brain-derived neurotrophic factor following cerebral ischemia may be involved in the development of glucose intolerance.
基金the National Natural Science Foundation of China(No.51976018)the National Natural Science Foundation for Young Scientists of China(No.51606022)+3 种基金Natural Science Foundation of Chongqing,China(No.cstc2017jcyjAX0203)Scientific Research Foundation for Returned Overseas Chinese Scholars of Chongqing,China(No.cx2017020)the Fundamental Research Funds for the Central Universities(No.106112016CDJXY145504)Research Funds of Key Laboratory of Low-grade Energy Utilization Technologies and Systems(No.LLEUTS-2018005).
文摘This study investigated the important factors that affect the operating parameters of thermally regenerative ammoniabased batteries(TRABs),including the metal electrode type,membrane type,electrode surface area,electrode distance,electrolyte concentration,and ammonia concentration.The experimental results showed that the maximum power density of TRABs with a Cu electrode was 40.0 W·m^(2),which was considerably higher than that with Ni(0.34 W·m^(2))and Co(0.14 W·m^(2))electrodes.TRABs with an anion exchange membrane had a 28.6%higher maximum power density than those with a cation exchange membrane.An increased electrode surface resulted in an increased maximum power but a decreased maximum power density.Within a certain range,TRAB performance was enhanced with decreased electrode distance and increased electrolyte concentration.An increased ammonia concentration resulted in enhanced ammonia transfer and improved the TRAB performance.
基金The National Natural Science Foundation of China (41401534)The Open Fund of State Key Laboratory of Geographic Information Engineering (SKLGIE2013-M-3-1).
文摘This article focuses on the first aspect of the album of deep learning: the deep convolutional method. The traditional matching point extraction algorithm typically uses manually designed feature descriptors and the shortest distance between them to match as the matching criterion. The matching result can easily fall into a local extreme value, which causes missing of the partial matching point. Targeting this problem, we introduce a two-channel deep convolutional neural network based on spatial scale convolution, which performs matching pattern learning between images to realize satellite image matching based on a deep convolutional neural network. The experimental results show that the method can extract the richer matching points in the case of heterogeneous, multi-temporal and multi-resolution satellite images, compared with the traditional matching method. In addition, the accuracy of the final matching results can be maintained at above 90%.
基金supported in part by National Natural Science Foundation of China(Nos.51522706,51877214,and 51607187)in part by the National Basic Research Program of China(973 Program)(No.613262)。
文摘In order to investigate the influence of aluminum vapor on the breakdown performance of air,this paper makes a study of the dielectric breakdown characteristics of Al-air mixture in the temperature range of 300-5000 K at atmospheric pressure.A Boltzmann analysis method is used to deal with the electron energy distribution function(EEDF),the reduced ionization coefficients(α/N),the reduced attachment coefficients(η/N)and the critical reduced breakdown strength((E/N)cr)so as to explore the influence of temperature and mixing ratio on the dielectric breakdown properties.In the temperature range of 300-2000 K,the property of the mixture is mainly determined by the mixing proportion of aluminum vapor because the composition of particles remains unchanged.In the temperature range of 2000-2500 K,the decomposition of Al2O_(2)leads to the increase of aluminum oxides and NO,and a rise in the percentage of highenergy electrons as well as the increment ofα/N.Also,the joint action of O_(2)and NO makesη/N increase first and then decrease,and(E/N)crgoes down to a smaller temperature range.An increase in the proportion of aluminum vapor causes(E/N)crto decrease in the low-temperature region and to increase in the high-temperature region,which will reduce the transition between these two temperature regions.
基金supported by the Key Laboratory of Meteorological Disaster of Ministry of Education (KLME050202 and 050205)the Jiangsu provincial 333 Talent Cultivation Projectthe Jiangsu provincial Qing-Lan Project and the Special Funds for Public Welfare of China [Grant No. GYHY(QX) 2007-6-26]Education Foundation, Hong Kong
文摘By using a surface air temperature index (SATI) averaged over the eastern Tibetan Plateau (TP), investigation is conducted on the short-term climate variation associated with the interannual air warming (or cooling) over the TP in each summer month. Evidence suggests that the SATI is associated with a consistent teleconnection pattern extending from the TP to central-western Asia and southeastern Europe. Associated rainfall changes include, for a warming case, a drought in northern India in May and June, and a stronger mei-yu front in June. The latter is due to an intensified upper-level northeasterly in eastern China and a wetter and warmer condition over the eastern TP. In the East Asian regions, the time-space distributions of the correlation patterns between SATI and rainfall are more complex and exhibit large differences from month to month. Some studies have revealed a close relationship between the anomalous heating over the TP and the rainfall anomaly along the Yangtze River valley appearing in the summer on a seasonal mean time-scale, whereas in the present study, this relationship only appears in June and the signal's significance becomes weaker after the long-term trend in the data was excluded. Close correlations between SATI and the convection activity and SST also occur in the western Pacific in July and August: A zonally-elongated warm tone in the SST in the northwestern Pacific seems to be a passive response of the associated circulation related to a warm SATI. The SATI-associated teleconnection pattern provides a scenario consistently linking the broad summer rainfall anomalies in Europe, central-western Asia, India, and East Asia.
基金the National Natural Science Foundation of China(Grant No.92065113)the National Key R&D Program。
文摘We present numerical results of a one-dimensional spin–orbit coupled Bose–Einstein condensate expanding in a speckle disorder potential by employing the Gross–Pitaevskii equation.Localization properties of a spin–orbit coupled Bose–Einstein condensate in zero-momentum phase,magnetic phase and stripe phase are studied.It is found that the localizing behavior in the zero-momentum phase is similar to the normal Bose–Einstein condensate.Moreover,in both magnetic phase and stripe phase,the localization length changes non-monotonically as the fitting interval increases.In magnetic phases,the Bose–Einstein condensate will experience spin relaxation in disorder potential.
基金National Natural Science Foundation of China(Nos.41671409,41401534)
文摘In this paper,an efficient technique for removing strip noise from remote sensing images is proposed in order to better retain image details.Firstly,the remote sensing image with strip noise is decomposed by wavelet technology;Secondly,two variational models are constructed,stripe preserve variation model and a destriping variation model.In order to efficiently separate the detail information in the low level high-frequency component,the stripe preserve variation model eliminates the detail information from the low level high-frequency component(including strip noise)while maintaining the strip noise(including strip noise).In order to successfully save the details in the high level high-frequency component,the destriping variation model eliminates the strip noise in the high level high-frequency component(including the strip noise).Finally,wavelet reconstruction is used to get the denoised image.It is clear from a comparison with previous approaches that the suggested method not only successfully removes strip noise but also preserves image details.
文摘Using Embedded-atom-method (EAM) potential, we have performed in detail molecular dynamics studies on a Fe adatom adsorption and diffusion dynamics on three low miller index surfaces, Fe (110), Fe (001), and Fe (111). Our results present that adatom adsorption energies and diffusion barriers on these surfaces have similar monotonic trend: adsorption energies, Ea(110) Ea(001) Ea(111), diffusion barriers, Ed(110) Ed(001) Ed(111). On the Fe (110) surface, adatom simple jump is the main diffusion mechanism with relatively low energy barrier;nevertheless, adatoms exchange with surface atoms play a dominant role in surface diffusion on the Fe (001).
文摘With the continuous economic growth,human resources service industry also plays an important role in the economic development.In order to explore the development of human resources service industry in Xinxiang,based on a survey of more than 50 enterprises and organizations in Xinxiang,Xinxiang’s human resources service industry has a bright future,however,there are still some problems in the aspects of enterprise scale,personnel skills and agglomeration management.Therefore,different countermeasures are put forward for different roles to solve the development obstacles and promote the development of industry agglomeration,building a new type of human resources to serve the ecological industry chain.
基金the Strategic Priority Research Program of the Chinese Academy of Sciences(No.XDB 0470303)the Fund of Natural Science Foundation of China(No.52073132)the Fundamental Research Funds for the Central Universities(Nos.zujbky-2022-ey02 and Izujbky-2023-eyt03).
文摘Additive manufacturing technology,by manipulating and emulating inherent multiscale,multi-material,and multifunctional structures found in nature,has created new opportunities for constructing heterogeneous structures associated with special properties and achieving ultra-high mechanical performance and reliability in ceramic composite materials.In this study,we have developed an innovative fabrication method designated as coaxial 3D printing for the synchronous construction of two constituents into ceramic composites with a tooth enamel biomimetic microstructure.Herein,the stiff silicate and flexible epoxy served as a strengthening bridge and toughening layer,respectively.The method differed from the traditional approach of randomly dispersing reinforcing components within a ceramic matrix.It allowed for the direct creation of an internally effective three-dimensional reinforcement network structure in ceramic composites.This process facilitated synergistic deformation and simultaneous enhancement of multiple materials and hierarchical structures.Owing to the uniform distribution of internal stress and effective block of microcrack propagation,the biomimetically structured silicate/epoxy ceramic composite has demonstrated much significant enhancement in mechanical properties,includingcompressive strength(48.8±3.12MPa),flexuralstrength(10.39±1.23MPa),andflexuraltoughness(218.7±54.6kJ/m^(3)),which was 0.5,2.1,and 47.5 times as high as those of the intrinsic brittle silicate ceramics,respectively.In-situ characterization and multiscale finite element simulation of microstructural evolution during three-point bending deformation further validated multiple-step features of the fracture process(silicate bridge fracture,interface detachment,epoxy extraction,and rupture),which benefited from interpenetrating structural features achieved by coaxial printing to accomplish with the complex propagating routines of the crack deflection in silicate ceramic composites.This coaxial 3D printing method paves the way for tailored toughening-strengthening designs for other brittle engineering ceramic materials.
基金the National Key R&D Program of China(Grant No.2022YFB3809000)the Intellectual Property Program of Gansu(Grant No.22ZSCQ043).
文摘The tribological properties of self-lubricating composites are influenced by many variables and complex mechanisms.Data-driven methods,including machine learning(ML)algorithms,can yield a better comprehensive understanding of complex problems under the influence of multiple parameters,typically for how tribological performances and material properties correlate.Correlation of friction coefficients and wear rates of copper/aluminum-graphite(Cu/Al-graphite)self-lubricating composites with their inherent material properties(composition,lubricant content,particle size,processing process,and interfacial bonding strength)and the variables related to the testing method(normal load,sliding speed,and sliding distance)were analyzed using traditional approaches,followed by modeling and prediction of tribological properties through five different ML algorithms,namely support vector machine(SVM),K-Nearest neighbor(KNN),random forest(RF),eXtreme gradient boosting(XGBoost),and least-squares boosting(LSBoost),based on the tribology experimental data.Results demonstrated that ML models could satisfactorily predict friction coefficient and wear rate from the material properties and testing method variables data.Herein,the LSBoost model based on the integrated learning algorithm presented the best prediction performance for friction coefficients and wear rates,with R^(2) of 0.9219 and 0.9243,respectively.Feature importance analysis also revealed that the content of graphite and the hardness of the matrix have the greatest influence on the friction coefficients,and the normal load,the content of graphite,and the hardness of the matrix influence the wear rates the most.
基金the Geological Investigation Work project of China Geological Survey(Grant No.DD20190172)the National Key R&D Plan of China(Grant No.2017YFC0602806).
文摘The felsic volcanogenic tuffs named"green-bean rocks"(GBRs),characterized by a green or yellowish green color,are widely distributed in the western Yangtze platform and have a high lithium content(286-957 ppm).This paper studies the ages,origin and tectonic setting of the GBRs in the Sichuan basin on the western margin of the Yangtze platform through the whole-rock geochemistry and zircon trace elements by using U-Pb dating and Hf-O isotopes.The GBR samples from the Quxian and Beibei sections yielded zircon U-Pb ages of 245.5±1.8 Ma and 244.8±2.2 Ma.These samples can be used as the isochronous stratigraphic marker of the Early-Middle Triassic boundary(EMTB)for regional correlation.The whole-rock and zircon geochemistry,and zircon Hf-O isotopes exhibited S-type geochemical affinities with high positiveδ^(18)0 values(9.28‰-11.98‰),low negativeε_(Hf)(t)values(-13.87 to-6.79),and T_(DM)^(2)ages of 2150-1703 Ma,indicating that the lithium-rich GBRs were generated by the remelting of the pre-existing ancient Paleoproterozoic layer without mantle source contamination in the arcrelated/orogenic tectonic setting.The results of this study demonstrate that the lithium-rich GBRs in the western Yangtze platform were derived from arc volcanic eruptions along the Sanjiang orogen,triggered by the closure of the eastern Paleo-Tethys Ocean and the syn-collision between the continental Indochina and Yangtze blocks at ca.247 Ma.This was marked by a major shift from I-type magmas with intermediateε_(Hf)(t)values to S-type magmas with low negativeε_(Hf)(t)values.Collectively,our results provide new insights into the origin of the GBRs and decodes the closure of the eastern Paleo-Tethys.
基金supported by Innovative Research Group Project of National Natural Science Foundation of China (No. 52021004)National Natural Science Foundation of China (No. 51976018)+1 种基金Scientific Research Foundation for Returned Overseas Chinese Scholars of Chongqing, China (No. cx2021088)Research Funds of Key Laboratory of Low-grade Energy Utilization Technologies and Systems (No. LLEUTS-2018005)。
文摘Thermally regenerative batteries(TRBs) are promising for harvesting low-grade waste heat into electrical power. However, the ammonia crossover from anode to cathode causes self-discharge and then leads to the decay of capacity. To alleviate the ammonia crossover and improve electricity generation, a stable graphene oxide(GO) modified anion exchange membrane(AEM) was proposed. Compared with the original AEM, the GO modified AEM with a 39.5% lower ammonia permeability induces a 24.3% higher maximal power output and 20.2% higher energy density in TRBs. Together with the visualization result,it was demonstrated the ammonia crossover was effectively alleviated by GO modifying the AEM not at a cost of the reduced battery performance, indicating the promising application in future TRBs.
基金The study was supported by the Project from State Key Laboratory of Radiation Medicine and Protection(GZK1202221)the Nuclear Technology Application Excellent Experts Program of the Second Affiliated Hospital of Soochow University(XKTJ-HRC2021002),China.
文摘Objective:To investigate the differences in small intestinal toxicity and taxonomic composition,diversity,and functional pathways of gut microbiome and metabolome after different radiotherapies in mouse colorectal cancer(CRC)model.Methods:Azoxymethane/dextran sodium sulfate(AOM/DSS)-induced mouse CRC model was treated with single pulse FLASH-RT(dose rate 100 Gy/s)or CONV-RT(dose rate 2 Gy/min)at whole abdomen.At 12 d after radiotherapy,sections of small intestinal tract tissue were dissected for hematoxylin and eosin(HE)staining and the fresh feces were collected for 16S ribosomal RNA(rRNA)microbiome sequencing and liquid chromatography and mass spectrometry(LC-MS)metabolomics sequencing to assess changes in the gut microbiota and metabolites.Microbial high-throughput 16S rRNA data was analyzed with QIIME2 and LEfSe softwares.ProteoWizard,XCMS and Ropls softwares were used for LC-MS analysis.Results:HE staining showed that FLASH-RT maintained small intestinal integrity and reduced the radiotherapyinduced injury.Sequencing analysis of gut fecal microbiome showed that phylum Bacteroidetes and genera Prevotella and Lactobacillus of microbial community were increased after FLASH-RT.Metabolomics sequencing analysis revealed that the metabolites after FLASH-RT were enriched in amino acid metabolism,while cholesterol metabolism was top enriched after CONV-RT.Conclusions:FLASH-RT significantly mitigates the small intestine tissue damage compared with CONV-RT.FLASHRT and CONV-RT have different impact on gut microbiota and its metabolites.Our results provide a theoretical basis for the early evaluation,prediction and individualized treatment of the irradiation effect after novel FLASHRT on tumors through the evaluation of intestinal microbiota and metabolites.
基金Foundation of China(Nos.21908204,52074244,2022TQ0285 and 52206282)and the Center of Advanced Analysis&Computational Science,Zhengzhou University for their characterization。
文摘Mn-based Prussian blue analogues(Mn-PBAs),featuring a three-dimensional(3D)metal-organic framework and multiple redox couples,have gained wide interests in Zn-ion batteries(ZIBs).However,owing to the Jahn-Teller distortion and disproportionation reaction of Mn^(3+),these materials suffer from poor electrochemical performances and inferior structural stability.Herein,we prepare a typical high-entropy Prussian blue analogue(HE-PBA)with increased configuration entropy through integrating five transition metal elements of Mn,Co,Ni,Fe and Cu into the nitrogen-coordinated-M-lattice sites.Consequently,the HE-PBA presents enhanced uptake of Zn^(2+)with 80 mAh·g^(−1)compared to those medium-entropy PBAs,low-entropy PBAs and conventional PBAs,which can be assigned to“cocktail”effect of multiple transition metal active redox couples.Furthermore,a phase transition process from monoclinic phase to rhombohedral phase occurs in HE-PBA cathode,resulting in a stable structure of MN6(M=Mn,Co,Fe,Ni,Cu)and ZnN4 co-linked to FeC6 through the cyanide ligands.Additionally,the advantages of entropy-driven stability are also confirmed by the calculated reduction energy and the density of states between HE-PBA and KMn[Fe(CN)6](KMnHCF).This work not only presents a high-performance HE-PBA cathode in ZIBs,but also introduces a novel concept of high entropy benefiting for designing advanced materials.
基金supported by the National Natural Science Foundation of China (51902317)the Key Research Program of the Chinese Academy of Sciences (XDPB24)+1 种基金the State Key Laboratory of New Ceramic and Fine Processing Tsinghua University (KF201911)the Key Research and Development Project of Gansu Province (20YF8GA001).
文摘High-entropy carbides are a nascent group of ceramics that are promising for high-temperature applications due to the combination of good stability,high hardness(H),high strength,and superior creep resistance that they display.Due to high melting points and low lattice diffusion coefficients,however,the high-entropy carbides are usually difficult to consolidate to a nearly full density.To cope with this challenge,herein,binary carbides including TiC,V_(8)C_(7),NbC,Mo_(2)C,and WC with different carbon stoichiometry were used to prepare dense high-entropy(TiVNbMoW)C_(4.375),and the influence of carbon vacancy on formation ability and mechanical properties of carbon-deficient high-entropy(TiVNbMoW)C_(4.375) were investigated.Intriguingly,although the starting binary carbides have different crystal structures and carbon stoichiometry,the as-prepared high-entropy material showed a rock-salt structure with a relatively high density(98.1%)and good mechanical properties with hardness of 19.4±0.4 GPa and fracture toughness(KIC)of 4.02 MPa·m^(1/2).More importantly,the high-entropy(TiVNbMoW)C_(4.375) exhibited low coefficient of friction(COF)at room temperature(RT)and 800℃.Wear rate(W)gradually increased with the temperature rising,which were attributed to the formation of low-hardness oxidation films at high temperatures to aggravate wear.At 800℃,lubricating films formed from sufficient oxidation products of V_(2)O_(5) and MoO_(3) effectively improved tribological behavior of the high-entropy(TiVNbMoW)C_(4.375).Wear mechanisms were mainly abrasive wear resulting from grain pullout and brittle fracture as well as oxidation wear generated from high-temperature reactions.These results are useful as valuable guidance and reference to the synthesis of high-entropy ceramics(HECs)for sliding parts under high-temperature serving conditions.