AIM: To identify the cut-off value for predicting the ability of elderly patients with dysphagia to swallow pureed diets using a new endoscopy scoring method. METHODS: Endoscopic swallowing evaluation of pureed diets ...AIM: To identify the cut-off value for predicting the ability of elderly patients with dysphagia to swallow pureed diets using a new endoscopy scoring method. METHODS: Endoscopic swallowing evaluation of pureed diets were done in patients ≥ 65 years with dysphagia. The Hyodo-Komagane score for endoscopic swallowing evaluation is expressed as the sum(0-12) of four degrees(0-3) with four parameters:(1) salivary pooling in the vallecula and piriform sinuses;(2) the response of glottal closure reflex induced by touching the epiglottis with the endoscope;(3) the location of the bolus at the time of swallow onset assessed by "white-out" following swallowing of test jelly; and(4) pharyngeal clearance after swallowing of test jelly. We used receiver operating characteristic(ROC) curve analysis to retrospectively analyze the association between the total score and successful oral intake of pureed diets. RESULTS: One hundred and seventy-eight patients were enrolled including 113 men(63%), mean age 83 years(range, 66-98). One hundred and twenty-six patients(71%) were able to eat pureed diets during the observation period(mean ± SD, 19 ± 14 d). In ROC analysis, the cut-off value of the score for eating the pureed diets was 7(sensitivity = 0.98; specificity = 0.91).CONCLUSION: The Hyodo-Komagane endoscopic score is useful to predict the ability to eat pureed diets in elderly patients with dysphagia.展开更多
Ultrafine-grained(UFG)pure titanium was produced by equal channel angular pressing for 4 passes,followed by rotatory swaging at room temperature.The strain-controlled low-cycle fatigue tests of UFG and coarse-grained(...Ultrafine-grained(UFG)pure titanium was produced by equal channel angular pressing for 4 passes,followed by rotatory swaging at room temperature.The strain-controlled low-cycle fatigue tests of UFG and coarse-grained(CG)pure titanium were conducted by Instron electro-hydraulic servo fatigue testing machine in the strain amplitude range of 0.5%—1.1%at room temperature.Transmission electron microscope(TEM)and scanning electron microscope were used to investigate the microstructure and fracture surface of UFG pure titanium after fatigue tests.Results show that UFG pure titanium exhibits a longer low-cycle fatigue life,compared with the CG pure titanium.For example,at a total strain amplitude of 0.5%,UFG and CG pure titanium has fatigue life of 10850 and 4820 cycles,respectively.Significant cyclic softening occurs in UFG pure titanium,except in the case of a total strain amplitude of 0.5%.Hysteresis loop area is increased rapidly with the increase in strain amplitude.The fracture surface shows that the fatigue crack is initiated from the specimen surface.A series of fatigue striations and many microcracks exist in the propagation region.With the increase in strain amplitude,the predominant failure mode is transformed from ductile failure into quasi-cleavage failure.Dislocation slip is the main plastic deformation mechanism of UFG pure titanium during low-cycle fatigue deformation.展开更多
In this paper,we identify conditions on the change of rings to induce functors between the two pure derived(resp.,pure singularity)categories.Then we construct recollements of pure derived categories and pure singular...In this paper,we identify conditions on the change of rings to induce functors between the two pure derived(resp.,pure singularity)categories.Then we construct recollements of pure derived categories and pure singularity categories for a formal triangular matrix ring,respectively.As an application,we study the pure global dimension of a formal triangular matrix ring.展开更多
THE mechanical response and deformation mechanisms of pure nickel under nanoindentation were systematically investigated using molecular dynamics(MD)simulations,with a particular focus on the novel interplay between c...THE mechanical response and deformation mechanisms of pure nickel under nanoindentation were systematically investigated using molecular dynamics(MD)simulations,with a particular focus on the novel interplay between crystallographic orientation,grain boundary(GB)proximity,and pore characteristics(size/location).This study compares single-crystal nickel models along[100],[110],and[111]orientations with equiaxed polycrystalline models containing 0,1,and 2.5 nm pores in surface and subsurface configurations.Our results reveal that crystallographic anisotropy manifests as a 24.4%higher elastic modulus and 22.2%greater hardness in[111]-oriented single crystals compared to[100].Pore-GB synergistic effects are found to dominate the deformation behavior:2.5 nm subsurface pores reduce hardness by 25.2%through stress concentration and dislocation annihilation at GBs,whereas surface pores enable mechanical recovery via accelerated dislocation generation post-collapse.Additionally,size-dependent deformation regimes were identified,with 1 nm pores inducing negligible perturbation due to rapid atomic rearrangement,in contrast with persistent softening in 2.5 nm pores.These findings establish atomic-scale design principles for defect engineering in nickel-based aerospace components,demonstrating how crystallographic orientation,pore configuration,and GB interactions collectively govern nanoindentation behavior.展开更多
The scaling-up of electrochemical CO_(2)reduction requires circumventing the CO_(2)loss as carbonates under alkaline conditions.Zero-gap MEA cell configurations with a proton exchange membrane represent an alternative...The scaling-up of electrochemical CO_(2)reduction requires circumventing the CO_(2)loss as carbonates under alkaline conditions.Zero-gap MEA cell configurations with a proton exchange membrane represent an alternative solution in a pure acidic system,but the catalyst layer in direct contact with the hydrated proton environment usually leads to H_(2)evolution dominating.Herein,we show that polydimethyldiallyl-ammonium-chloride-coated Ag(Ag@PDDA)electrode exhibits outstanding performance with a FE of 86%,a single-pass conversion of 72%,and a stability of 28 h for CO production in pure-acid MEA compared with ammonium poly(N-methyl-piperidine-co-pterphenyl)decorated Ag(Ag/QAPPT)and cetyltrimethylammonium bromide decorated Ag(Ag/CTAB).The in situ ATR-SEIRAS reveal that PDDA creates a positive charge-rich protective outer layer and an N-rich hybrid inner layer,which not only suppresses the migration of H+during the electrolysis process and blocks the direct contact between H2O and Ag catalyst,but also promotes the generation from CO_(2)to*COOH in a pure-acid system.This work highlights the importance of polyelectrolyte engineering in regulating the electrocatalytic interface and accelerates the development of proton exchange membrane CO_(2)electrolysis.展开更多
The development of novel quantum many-body computational algorithms relies on robust benchmarking.However,generating such benchmarks is often hindered by the massive computational resources required for exact diagonal...The development of novel quantum many-body computational algorithms relies on robust benchmarking.However,generating such benchmarks is often hindered by the massive computational resources required for exact diagonalization or quantum Monte Carlo simulations,particularly at finite temperatures.In this work,we propose a new algorithm for obtaining thermal pure quantum states,which allows efficient computation of both mechanical and thermodynamic properties at finite temperatures.We implement this algorithm in our open-source C++template library,Physica.Combining the improved algorithm with state-of-the-art software engineering,our implementation achieves high performance and numerical stability.As an example,we demonstrate that for the 4×4 Hubbard model,our method runs approximately 10~3times faster than HΦ3.5.2.Moreover,the accessible temperature range is extended down toβ=32 across arbitrary doping levels.These advances significantly push forward the frontiers of benchmarking for quantum many-body systems.展开更多
The doubled haploid(DH)technique accelerates homozygosity by inducing chromosome doubling in haploid embryos derived from hybrid plants.This approach offers significant advantages over conventional rice breeding metho...The doubled haploid(DH)technique accelerates homozygosity by inducing chromosome doubling in haploid embryos derived from hybrid plants.This approach offers significant advantages over conventional rice breeding methods by shortening the breeding cycle and enabling rapid development of pure homozygous lines.Anther culture(AC)has been established as an efficient and successful method for producing DH plants via androgenesis in rice.However,despite its success in japonica rice.展开更多
Pure Mg boasting a relatively small corrosion rate is a potential biodegradable metal material for implants.However,its degradation behavior in the complex physiological environment is still a lack of understanding.In...Pure Mg boasting a relatively small corrosion rate is a potential biodegradable metal material for implants.However,its degradation behavior in the complex physiological environment is still a lack of understanding.In this work,we investigated the effect of corrosion product film layers on the degradation behavior of pure Mg in physiological environments.Pure Mg shows a faster corrosion rate in simulated body fluid(SBF)compared to NaCl solution.Hydrogen evolution experiments indicate that the degradation rate of pure Mg in SBF decreases rapidly within the first 12 h but stabilizes afterward.The rapid deposition of low-solubility calcium phosphate on the pure Mg in SBF provides protection to the substrate,resulting in a gradual decrease in the degradation rates.Consequently,the corrosion product film of pure Mg formed in SBF exhibits a layered structure,with the upper layer consisting of dense Ca_(3)(PO_(4))_(2)/Mg_(3)(PO_(4))_(2) and the lower layer consisting of Mg(OH)_(2)/MgO.Electrochemical impedance spectroscopy(EIS)shows that the resistance of the corrosion product film increases over time,indicating gradual strengthening of the corrosion resistance.The 4-week degradation results in the femoral marrow cavity of mice are consistent with the result in SBF in vitro.展开更多
The features of additive manufacturing(AM)have made commercially pure titanium(CP-Ti)an attractive candidate material for biomedical implants.However,achieving high strength and ductility is challenging because of the...The features of additive manufacturing(AM)have made commercially pure titanium(CP-Ti)an attractive candidate material for biomedical implants.However,achieving high strength and ductility is challenging because of the columnar structures and fine martensite formation.This study investigated the effect of carbon nanotubes(CNTs)addition on the microstructure and mechanical properties of grade 1 CP-Ti(Gr-1)during the laser powder bed fusion(L-PBF)process.A minute amount of 0.2%mass fraction(wt%)CNTs addition resulted in a high yield strength of approximately 700 MPa and exceptional ductility of 25.7%.Therein,a portion of the CNTs dissolved in the matrix as solute atoms,contributing to solution strengthening,while others were transformed into Ti C_(x)through an in situ reaction with the Ti matrix.Furthermore,the addition of CNTs resulted in the formation of a larger fraction of equiaxed grains and increased the activity of basal and prismatic slip systems.Hence,Gr-1 with CNTs exhibited significantly increased ductility while maintaining a high strength comparable to that of Gr-1 without CNTs.The insights gained from this study provide a novel approach for designing strong and ductile Ti alloys for AM.展开更多
In order to study the characteristics of pure fly ash-based geopolymer concrete(PFGC)conveniently,we used a machine learning method that can quantify the perception of characteristics to predict its compressive streng...In order to study the characteristics of pure fly ash-based geopolymer concrete(PFGC)conveniently,we used a machine learning method that can quantify the perception of characteristics to predict its compressive strength.In this study,505 groups of data were collected,and a new database of compressive strength of PFGC was constructed.In order to establish an accurate prediction model of compressive strength,five different types of machine learning networks were used for comparative analysis.The five machine learning models all showed good compressive strength prediction performance on PFGC.Among them,R2,MSE,RMSE and MAE of decision tree model(DT)are 0.99,1.58,1.25,and 0.25,respectively.While R2,MSE,RMSE and MAE of random forest model(RF)are 0.97,5.17,2.27 and 1.38,respectively.The two models have high prediction accuracy and outstanding generalization ability.In order to enhance the interpretability of model decision-making,we used importance ranking to obtain the perception of machine learning model to 13 variables.These 13 variables include chemical composition of fly ash(SiO_(2)/Al_(2)O_(3),Si/Al),the ratio of alkaline liquid to the binder,curing temperature,curing durations inside oven,fly ash dosage,fine aggregate dosage,coarse aggregate dosage,extra water dosage and sodium hydroxide dosage.Curing temperature,specimen ages and curing durations inside oven have the greatest influence on the prediction results,indicating that curing conditions have more prominent influence on the compressive strength of PFGC than ordinary Portland cement concrete.The importance of curing conditions of PFGC even exceeds that of the concrete mix proportion,due to the low reactivity of pure fly ash.展开更多
High-performance pure nickel N6/steel 45#composite plate(N6/45#)was prepared using explosive welding technique.The microstructure of the interface and nearby regions was characterized and analyzed by optical microscop...High-performance pure nickel N6/steel 45#composite plate(N6/45#)was prepared using explosive welding technique.The microstructure of the interface and nearby regions was characterized and analyzed by optical microscope,scanning electron microscope,electron backscatter diffraction,and mechanical property testing,and the microstructural features and mechanical properties of the explosive welding interface were explored.The results show that along the direction of explosive welding,the pure nickel N6/steel 45#composite plate interface gradually evolves from a flat bond to a typical wavy bond.The grains at the crests and troughs exhibit high heterogeneity,and the closer to the interface,the finer the grains.Recrystallization and low-stress deformation bands are formed at the bonding interface.Nanoindentation tests reveal that plastic deformation occurs in the interfacial bonding zone,and the nanohardness values in the crest regions are higher than that in the trough regions.The tensile strength of the N6/45#interface is 599.8 MPa,with an average shear strength of 326.3 MPa.No separation phenomenon is observed between N6 and 45#after the bending test.展开更多
Dear Editor,This letter investigates the fuzzy prescribed-time control(PTC)problem for a class of uncertain pure feedback nonlinear systems.Firstly,a novel prescribed-time stability lemma is introduced,which plays a c...Dear Editor,This letter investigates the fuzzy prescribed-time control(PTC)problem for a class of uncertain pure feedback nonlinear systems.Firstly,a novel prescribed-time stability lemma is introduced,which plays a critical role in stability analysis.Unlike existing PTC algorithms,where the nonlinear functions are typically known or satisfy a linear growth condition,our approach does not require such assumptions.To address these unknown factors,fuzzy logic systems(FLSs)are employed.Based on the new prescribed-time stability lemma,it is proven that the controller and all system states converge to the origin within the prescribed time and remain there.Finally,the effectiveness of the proposed algorithm is validated through a simulation example.展开更多
This study investigates the fracture behavior of clay-rich mudstone under varying temperature and pressure conditions,which is crucial for the safety of geological structures.It focuses on three fracture types:pure mo...This study investigates the fracture behavior of clay-rich mudstone under varying temperature and pressure conditions,which is crucial for the safety of geological structures.It focuses on three fracture types:pure mode I tensile fractures,pure mode II tensile fractures,and shear fractures,examining specimens at room temperature(RT)and after thermal treatments at 250 and 500℃.The findings reveal that increasing temperatures makes the mudstone more brittle,enhancing fracture velocity,toughness,load-bearing capacity,roughness,and the fracture process zone(FPZ)radius.Notably,tensile fractures induced under pure mode II displayed the highest velocities,while shear fractures exhibited the lowest velocities,smoothest surfaces,and greatest resistance to failure.The application of a confining pressure of 4 MPa significantly improved shear fracture toughness by 119.7%,98.5%and 71.9%at RT,250℃and 500℃,respectively,and reduced roughness by 8.2%,22.4%and 30.4%.This research offers a novel,comprehensive view of how temperature and pressure impact fractures in mudstone sensitive to temperature due to its high clay content and water affinity.The findings provide valuable insights applicable to geothermal energy,oil and gas exploration,and underground construction,thereby enhancing the understanding of fracture mechanics in geological contexts.展开更多
The Kanmuryojukyo(“The Meditation on the Buddha of Infinite Life Sutra”)is among the three principle canons of Pure Land Buddhism(Jpn.Jodo Shu and Jodo Shinshu)along with Amitayus Sutra and the Amitabha Sutra.Althou...The Kanmuryojukyo(“The Meditation on the Buddha of Infinite Life Sutra”)is among the three principle canons of Pure Land Buddhism(Jpn.Jodo Shu and Jodo Shinshu)along with Amitayus Sutra and the Amitabha Sutra.Although the original Sanskrit text was never found,it was translated into Chinese by a monk named Kalayasas in the 5th century and became an influential text in Mahayana Buddhism in East Asia with the help of commentaries written by notable Chinese scholars,such as Shandao in the 7th century.The sutra contains the story of Queen Vaidehi who is imprisoned by her murderous son Ajatasattu and visited by Shakyamuni Buddha in response to her prayer to be born in Amitabha’s pure land.Though in prison,the Buddha tells her how to be liberated and reborn in the pure land by meditating sixteen visualizations.展开更多
Journal overview:Journal of Mathematical Research with Applications(JMRA),formerly Journal of Mathematical Research and Exposition(JMRE)created in 1981,one of the transactions of China Society for Industrial and Appli...Journal overview:Journal of Mathematical Research with Applications(JMRA),formerly Journal of Mathematical Research and Exposition(JMRE)created in 1981,one of the transactions of China Society for Industrial and Applied Mathematics,is a home for original research papers of the highest quality in all areas of mathematics with applications.The target audience comprises:pure and applied mathematicians,graduate students in broad felds of sciences and technology,scientists and engineers interested in mathematics.展开更多
Pure drug nanomedicines(PDNs)encompass active pharmaceutical ingredients(APIs),including macromolecules,biological compounds,and functional components.They overcome research barriers and conversion thresholds associat...Pure drug nanomedicines(PDNs)encompass active pharmaceutical ingredients(APIs),including macromolecules,biological compounds,and functional components.They overcome research barriers and conversion thresholds associated with nanocarriers,offering advantages such as high drug loading capacity,synergistic treatment effects,and environmentally friendly production methods.This review provides a comprehensive overview of the latest advancements in PDNs,focusing on their essential components,design theories,and manufacturing techniques.The physicochemical properties and in vivo behaviors of PDNs are thoroughly analyzed to gain an in-depth understanding of their systematic characteristics.The review introduces currently approved PDN products and further explores the opportunities and challenges in expanding their depth and breadth of application.Drug nanocrystals,drug-drug cocrystals(DDCs),antibody-drug conjugates(ADCs),and nanobodies represent the successful commercialization and widespread utilization of PDNs across various disease domains.Self-assembled pure drug nanoparticles(SAPDNPs),a next-generation product,still require extensive translational research.Challenges persist in transitioning from laboratory-scale production to mass manufacturing and overcoming the conversion threshold from laboratory findings to clinical applications.展开更多
Journal overview:Journal of Mathematical Research with Applications(JMRA),formerly Journal of Mathematical Research and Exposition(JMRE)created in 1981,one of the transactions of China Society for Industrial and Appli...Journal overview:Journal of Mathematical Research with Applications(JMRA),formerly Journal of Mathematical Research and Exposition(JMRE)created in 1981,one of the transactions of China Society for Industrial and Applied Mathematics,is a home for original research papers of the highest quality in all areas of mathematics with applications.The target audience comprises:pure and applied mathematicians,graduate students in broad fields of sciences and technology,scientists and engineers interested in mathematics.展开更多
Seismic anisotropy has been extensively acknowledged as a crucial element that influences the wave propagation characteristic during wavefield simulation,inversion and imaging.Transversely isotropy(TI)and orthorhombic...Seismic anisotropy has been extensively acknowledged as a crucial element that influences the wave propagation characteristic during wavefield simulation,inversion and imaging.Transversely isotropy(TI)and orthorhombic anisotropy(OA)are two typical categories of anisotropic media in exploration geophysics.In comparison of the elastic wave equations in both TI and OA media,pseudo-acoustic wave equations(PWEs)based on the acoustic assumption can markedly reduce computational cost and complexity.However,the presently available PWEs may experience SV-wave contamination and instability when anisotropic parameters cannot satisfy the approximated condition.Exploiting pure-mode wave equations can effectively resolve the above-mentioned issues and generate pure P-wave events without any artifacts.To further improve the computational accuracy and efficiency,we develop two novel pure qP-wave equations(PPEs)and illustrate the corresponding numerical solutions in the timespace domain for 3D tilted TI(TTI)and tilted OA(TOA)media.First,the rational polynomials are adopted to estimate the exact pure qP-wave dispersion relations,which contain complicated pseudo-differential operators with irrational forms.The polynomial coefficients are produced by applying a linear optimization algorithm to minimize the objective function difference between the expansion formula and the exact one.Then,the developed optimized PPEs are efficiently implemented using the finite-difference(FD)method in the time-space domain by introducing a scalar operator,which can help avoid the problem of spectral-based algorithms and other calculation burdens.Structures of the new equations are concise and corresponding implementation processes are straightforward.Phase velocity analyses indicate that our proposed optimized equations can lead to reliable approximation results.3D synthetic examples demonstrate that our proposed FD-based PPEs can produce accurate and stable P-wave responses,and effectively describe the wavefield features in complicated TTI and TOA media.展开更多
Traveling through the vast snow-covered land of Xizang,the sacred plateau,one cannot help but be captivated by the natural grandeur:the azure skies with white clouds,snowy mountains,pure lakes,forests and grasslands w...Traveling through the vast snow-covered land of Xizang,the sacred plateau,one cannot help but be captivated by the natural grandeur:the azure skies with white clouds,snowy mountains,pure lakes,forests and grasslands where herds of sheep and yaks forage and stroll leisurely.展开更多
With the development of renewable energy,electrochemical carbon dioxide reduction reaction(CO_(2)RR)has become a potential solution for achieving carbon neutrality.However,until now,due to issues with salt precipitate...With the development of renewable energy,electrochemical carbon dioxide reduction reaction(CO_(2)RR)has become a potential solution for achieving carbon neutrality.However,until now,due to issues with salt precipitate and regeneration of the electrolyte,this technology faces challenges such as difficulty in maintaining long-term stable operation and excessive costs.The pure water CO_(2)electrolyzers are believed to be the ultimate solution to eliminate the salt depreciation and electrolyte issues.This study develops an in-situ method tailored for CO_(2)reduction in pure water.By employing distribution of relaxation times(DRT)analysis and in-situ electrochemical active surface area(ECSA)measurements,we carried out a comprehensive investigation into the mass transport and electrochemical active surface area of gas diffusion electrodes(GDE)under pure water conditions.The maximum 89%CO selectivity and high selectivity(>80%)in the range of 0-300 mA/cm^(2)were achieved using commercial Ag nanoparticles by rational design of catalyst layer.We found that ionomers influence the CO_(2)electrolyzers performance via affecting local pH,GDE-membrane interface,and CO_(2)transport,while catalyst loading mainly influences the active area and CO_(2)transport.This work provides benchmark and insights for future pure water CO_(2)electrolyzers development.展开更多
文摘AIM: To identify the cut-off value for predicting the ability of elderly patients with dysphagia to swallow pureed diets using a new endoscopy scoring method. METHODS: Endoscopic swallowing evaluation of pureed diets were done in patients ≥ 65 years with dysphagia. The Hyodo-Komagane score for endoscopic swallowing evaluation is expressed as the sum(0-12) of four degrees(0-3) with four parameters:(1) salivary pooling in the vallecula and piriform sinuses;(2) the response of glottal closure reflex induced by touching the epiglottis with the endoscope;(3) the location of the bolus at the time of swallow onset assessed by "white-out" following swallowing of test jelly; and(4) pharyngeal clearance after swallowing of test jelly. We used receiver operating characteristic(ROC) curve analysis to retrospectively analyze the association between the total score and successful oral intake of pureed diets. RESULTS: One hundred and seventy-eight patients were enrolled including 113 men(63%), mean age 83 years(range, 66-98). One hundred and twenty-six patients(71%) were able to eat pureed diets during the observation period(mean ± SD, 19 ± 14 d). In ROC analysis, the cut-off value of the score for eating the pureed diets was 7(sensitivity = 0.98; specificity = 0.91).CONCLUSION: The Hyodo-Komagane endoscopic score is useful to predict the ability to eat pureed diets in elderly patients with dysphagia.
基金Natural Science Foundation of Shaanxi Province (2023-JC-YB-312)。
文摘Ultrafine-grained(UFG)pure titanium was produced by equal channel angular pressing for 4 passes,followed by rotatory swaging at room temperature.The strain-controlled low-cycle fatigue tests of UFG and coarse-grained(CG)pure titanium were conducted by Instron electro-hydraulic servo fatigue testing machine in the strain amplitude range of 0.5%—1.1%at room temperature.Transmission electron microscope(TEM)and scanning electron microscope were used to investigate the microstructure and fracture surface of UFG pure titanium after fatigue tests.Results show that UFG pure titanium exhibits a longer low-cycle fatigue life,compared with the CG pure titanium.For example,at a total strain amplitude of 0.5%,UFG and CG pure titanium has fatigue life of 10850 and 4820 cycles,respectively.Significant cyclic softening occurs in UFG pure titanium,except in the case of a total strain amplitude of 0.5%.Hysteresis loop area is increased rapidly with the increase in strain amplitude.The fracture surface shows that the fatigue crack is initiated from the specimen surface.A series of fatigue striations and many microcracks exist in the propagation region.With the increase in strain amplitude,the predominant failure mode is transformed from ductile failure into quasi-cleavage failure.Dislocation slip is the main plastic deformation mechanism of UFG pure titanium during low-cycle fatigue deformation.
基金Supported by Scientific and Technological Innovation Programs of Higher Education Institutions in Shanxi(Grant No.2025L092)the National Natural Science Foundation of China(Grant No.12071120).
文摘In this paper,we identify conditions on the change of rings to induce functors between the two pure derived(resp.,pure singularity)categories.Then we construct recollements of pure derived categories and pure singularity categories for a formal triangular matrix ring,respectively.As an application,we study the pure global dimension of a formal triangular matrix ring.
基金The National Natural Science Foundation of China(Grant No.12462006)Beijing Institute of Structure and Environment Engineering Joint Innovation Fund(No.BQJJ202414).
文摘THE mechanical response and deformation mechanisms of pure nickel under nanoindentation were systematically investigated using molecular dynamics(MD)simulations,with a particular focus on the novel interplay between crystallographic orientation,grain boundary(GB)proximity,and pore characteristics(size/location).This study compares single-crystal nickel models along[100],[110],and[111]orientations with equiaxed polycrystalline models containing 0,1,and 2.5 nm pores in surface and subsurface configurations.Our results reveal that crystallographic anisotropy manifests as a 24.4%higher elastic modulus and 22.2%greater hardness in[111]-oriented single crystals compared to[100].Pore-GB synergistic effects are found to dominate the deformation behavior:2.5 nm subsurface pores reduce hardness by 25.2%through stress concentration and dislocation annihilation at GBs,whereas surface pores enable mechanical recovery via accelerated dislocation generation post-collapse.Additionally,size-dependent deformation regimes were identified,with 1 nm pores inducing negligible perturbation due to rapid atomic rearrangement,in contrast with persistent softening in 2.5 nm pores.These findings establish atomic-scale design principles for defect engineering in nickel-based aerospace components,demonstrating how crystallographic orientation,pore configuration,and GB interactions collectively govern nanoindentation behavior.
基金financial support of the National Natural Science Foundation of China(NSFC)(52394202,52021004,52301232,and 52476056)the Natural Science Foundation of Chongqing Province(2024NSCQ-MSX1109).
文摘The scaling-up of electrochemical CO_(2)reduction requires circumventing the CO_(2)loss as carbonates under alkaline conditions.Zero-gap MEA cell configurations with a proton exchange membrane represent an alternative solution in a pure acidic system,but the catalyst layer in direct contact with the hydrated proton environment usually leads to H_(2)evolution dominating.Herein,we show that polydimethyldiallyl-ammonium-chloride-coated Ag(Ag@PDDA)electrode exhibits outstanding performance with a FE of 86%,a single-pass conversion of 72%,and a stability of 28 h for CO production in pure-acid MEA compared with ammonium poly(N-methyl-piperidine-co-pterphenyl)decorated Ag(Ag/QAPPT)and cetyltrimethylammonium bromide decorated Ag(Ag/CTAB).The in situ ATR-SEIRAS reveal that PDDA creates a positive charge-rich protective outer layer and an N-rich hybrid inner layer,which not only suppresses the migration of H+during the electrolysis process and blocks the direct contact between H2O and Ag catalyst,but also promotes the generation from CO_(2)to*COOH in a pure-acid system.This work highlights the importance of polyelectrolyte engineering in regulating the electrocatalytic interface and accelerates the development of proton exchange membrane CO_(2)electrolysis.
基金Fu-Zhou Chen for helpful discussions.The work is partly supported by the National Key Research and Development Program of China(Grant No.2022YFA1402704)the National Natural Science Foundation of China(Grant No.12247101)。
文摘The development of novel quantum many-body computational algorithms relies on robust benchmarking.However,generating such benchmarks is often hindered by the massive computational resources required for exact diagonalization or quantum Monte Carlo simulations,particularly at finite temperatures.In this work,we propose a new algorithm for obtaining thermal pure quantum states,which allows efficient computation of both mechanical and thermodynamic properties at finite temperatures.We implement this algorithm in our open-source C++template library,Physica.Combining the improved algorithm with state-of-the-art software engineering,our implementation achieves high performance and numerical stability.As an example,we demonstrate that for the 4×4 Hubbard model,our method runs approximately 10~3times faster than HΦ3.5.2.Moreover,the accessible temperature range is extended down toβ=32 across arbitrary doping levels.These advances significantly push forward the frontiers of benchmarking for quantum many-body systems.
基金supported by the Science and Technology Innovation Program of Fujian Agriculture and Forestry University,China(Grant No.KFB22045)the General Program of Natural Science Foundation Fujian,China(Grant No.2023J01460).
文摘The doubled haploid(DH)technique accelerates homozygosity by inducing chromosome doubling in haploid embryos derived from hybrid plants.This approach offers significant advantages over conventional rice breeding methods by shortening the breeding cycle and enabling rapid development of pure homozygous lines.Anther culture(AC)has been established as an efficient and successful method for producing DH plants via androgenesis in rice.However,despite its success in japonica rice.
基金supported by the National Natural Science Foundation of China(52127801)Postdoctoral Fellowship Program of CPSF under Grant Number GZC20231545,China Postdoctoral Science Foundation(2024T170557 and 2023M742224)+1 种基金Shanghai Post-doctoral Excellence Program(No.2023440)City University of Hong Kong Donation Grants(DON-RMG No.9229021 and 9220061).
文摘Pure Mg boasting a relatively small corrosion rate is a potential biodegradable metal material for implants.However,its degradation behavior in the complex physiological environment is still a lack of understanding.In this work,we investigated the effect of corrosion product film layers on the degradation behavior of pure Mg in physiological environments.Pure Mg shows a faster corrosion rate in simulated body fluid(SBF)compared to NaCl solution.Hydrogen evolution experiments indicate that the degradation rate of pure Mg in SBF decreases rapidly within the first 12 h but stabilizes afterward.The rapid deposition of low-solubility calcium phosphate on the pure Mg in SBF provides protection to the substrate,resulting in a gradual decrease in the degradation rates.Consequently,the corrosion product film of pure Mg formed in SBF exhibits a layered structure,with the upper layer consisting of dense Ca_(3)(PO_(4))_(2)/Mg_(3)(PO_(4))_(2) and the lower layer consisting of Mg(OH)_(2)/MgO.Electrochemical impedance spectroscopy(EIS)shows that the resistance of the corrosion product film increases over time,indicating gradual strengthening of the corrosion resistance.The 4-week degradation results in the femoral marrow cavity of mice are consistent with the result in SBF in vitro.
基金financially supported by the National Key Research and Development Project of the Ministry of Science and Technology of China(No.2022YFB4601000)the Fundamental Research Funds for the Central Universities(No.2042023kf0103)the Ministry of Trade,Industry and Energy,Korea(No.20013095)。
文摘The features of additive manufacturing(AM)have made commercially pure titanium(CP-Ti)an attractive candidate material for biomedical implants.However,achieving high strength and ductility is challenging because of the columnar structures and fine martensite formation.This study investigated the effect of carbon nanotubes(CNTs)addition on the microstructure and mechanical properties of grade 1 CP-Ti(Gr-1)during the laser powder bed fusion(L-PBF)process.A minute amount of 0.2%mass fraction(wt%)CNTs addition resulted in a high yield strength of approximately 700 MPa and exceptional ductility of 25.7%.Therein,a portion of the CNTs dissolved in the matrix as solute atoms,contributing to solution strengthening,while others were transformed into Ti C_(x)through an in situ reaction with the Ti matrix.Furthermore,the addition of CNTs resulted in the formation of a larger fraction of equiaxed grains and increased the activity of basal and prismatic slip systems.Hence,Gr-1 with CNTs exhibited significantly increased ductility while maintaining a high strength comparable to that of Gr-1 without CNTs.The insights gained from this study provide a novel approach for designing strong and ductile Ti alloys for AM.
基金Funded by the Natural Science Foundation of China(No.52109168)。
文摘In order to study the characteristics of pure fly ash-based geopolymer concrete(PFGC)conveniently,we used a machine learning method that can quantify the perception of characteristics to predict its compressive strength.In this study,505 groups of data were collected,and a new database of compressive strength of PFGC was constructed.In order to establish an accurate prediction model of compressive strength,five different types of machine learning networks were used for comparative analysis.The five machine learning models all showed good compressive strength prediction performance on PFGC.Among them,R2,MSE,RMSE and MAE of decision tree model(DT)are 0.99,1.58,1.25,and 0.25,respectively.While R2,MSE,RMSE and MAE of random forest model(RF)are 0.97,5.17,2.27 and 1.38,respectively.The two models have high prediction accuracy and outstanding generalization ability.In order to enhance the interpretability of model decision-making,we used importance ranking to obtain the perception of machine learning model to 13 variables.These 13 variables include chemical composition of fly ash(SiO_(2)/Al_(2)O_(3),Si/Al),the ratio of alkaline liquid to the binder,curing temperature,curing durations inside oven,fly ash dosage,fine aggregate dosage,coarse aggregate dosage,extra water dosage and sodium hydroxide dosage.Curing temperature,specimen ages and curing durations inside oven have the greatest influence on the prediction results,indicating that curing conditions have more prominent influence on the compressive strength of PFGC than ordinary Portland cement concrete.The importance of curing conditions of PFGC even exceeds that of the concrete mix proportion,due to the low reactivity of pure fly ash.
基金Natural Science Foundation of Shanxi Province(202203021221149)Key Research and Development Program of Shanxi Province(202302010101006,202202150401016)+1 种基金Scientific Research Start-up Fund for the Introduction of Talents in Shanxi Institute of Electronic Science and Technology(2023RKJ021)Key R&D Program of Linfen City(2334)。
文摘High-performance pure nickel N6/steel 45#composite plate(N6/45#)was prepared using explosive welding technique.The microstructure of the interface and nearby regions was characterized and analyzed by optical microscope,scanning electron microscope,electron backscatter diffraction,and mechanical property testing,and the microstructural features and mechanical properties of the explosive welding interface were explored.The results show that along the direction of explosive welding,the pure nickel N6/steel 45#composite plate interface gradually evolves from a flat bond to a typical wavy bond.The grains at the crests and troughs exhibit high heterogeneity,and the closer to the interface,the finer the grains.Recrystallization and low-stress deformation bands are formed at the bonding interface.Nanoindentation tests reveal that plastic deformation occurs in the interfacial bonding zone,and the nanohardness values in the crest regions are higher than that in the trough regions.The tensile strength of the N6/45#interface is 599.8 MPa,with an average shear strength of 326.3 MPa.No separation phenomenon is observed between N6 and 45#after the bending test.
基金supported by the National Natural Science Foundation of China(U20A20187,U22A2050)the Science Fund of Hebei Province(F2024203134,F2023203100)+3 种基金the Science and Technology Development Grant of Hebei Province(20311803D)Hebei Innovation Capability Improvement Plan project(22567619H)Basic Research Project of Shijiazhuang(241791007A)the China Scholarship Council(CSC 202308130190).
文摘Dear Editor,This letter investigates the fuzzy prescribed-time control(PTC)problem for a class of uncertain pure feedback nonlinear systems.Firstly,a novel prescribed-time stability lemma is introduced,which plays a critical role in stability analysis.Unlike existing PTC algorithms,where the nonlinear functions are typically known or satisfy a linear growth condition,our approach does not require such assumptions.To address these unknown factors,fuzzy logic systems(FLSs)are employed.Based on the new prescribed-time stability lemma,it is proven that the controller and all system states converge to the origin within the prescribed time and remain there.Finally,the effectiveness of the proposed algorithm is validated through a simulation example.
基金Projects(19300604,19300751)supported by the ORSP at Abu Dhabi University,UAE。
文摘This study investigates the fracture behavior of clay-rich mudstone under varying temperature and pressure conditions,which is crucial for the safety of geological structures.It focuses on three fracture types:pure mode I tensile fractures,pure mode II tensile fractures,and shear fractures,examining specimens at room temperature(RT)and after thermal treatments at 250 and 500℃.The findings reveal that increasing temperatures makes the mudstone more brittle,enhancing fracture velocity,toughness,load-bearing capacity,roughness,and the fracture process zone(FPZ)radius.Notably,tensile fractures induced under pure mode II displayed the highest velocities,while shear fractures exhibited the lowest velocities,smoothest surfaces,and greatest resistance to failure.The application of a confining pressure of 4 MPa significantly improved shear fracture toughness by 119.7%,98.5%and 71.9%at RT,250℃and 500℃,respectively,and reduced roughness by 8.2%,22.4%and 30.4%.This research offers a novel,comprehensive view of how temperature and pressure impact fractures in mudstone sensitive to temperature due to its high clay content and water affinity.The findings provide valuable insights applicable to geothermal energy,oil and gas exploration,and underground construction,thereby enhancing the understanding of fracture mechanics in geological contexts.
文摘The Kanmuryojukyo(“The Meditation on the Buddha of Infinite Life Sutra”)is among the three principle canons of Pure Land Buddhism(Jpn.Jodo Shu and Jodo Shinshu)along with Amitayus Sutra and the Amitabha Sutra.Although the original Sanskrit text was never found,it was translated into Chinese by a monk named Kalayasas in the 5th century and became an influential text in Mahayana Buddhism in East Asia with the help of commentaries written by notable Chinese scholars,such as Shandao in the 7th century.The sutra contains the story of Queen Vaidehi who is imprisoned by her murderous son Ajatasattu and visited by Shakyamuni Buddha in response to her prayer to be born in Amitabha’s pure land.Though in prison,the Buddha tells her how to be liberated and reborn in the pure land by meditating sixteen visualizations.
文摘Journal overview:Journal of Mathematical Research with Applications(JMRA),formerly Journal of Mathematical Research and Exposition(JMRE)created in 1981,one of the transactions of China Society for Industrial and Applied Mathematics,is a home for original research papers of the highest quality in all areas of mathematics with applications.The target audience comprises:pure and applied mathematicians,graduate students in broad felds of sciences and technology,scientists and engineers interested in mathematics.
基金supported by the National Natural Science Foundation of China(Nos.82073782 and 82241002)。
文摘Pure drug nanomedicines(PDNs)encompass active pharmaceutical ingredients(APIs),including macromolecules,biological compounds,and functional components.They overcome research barriers and conversion thresholds associated with nanocarriers,offering advantages such as high drug loading capacity,synergistic treatment effects,and environmentally friendly production methods.This review provides a comprehensive overview of the latest advancements in PDNs,focusing on their essential components,design theories,and manufacturing techniques.The physicochemical properties and in vivo behaviors of PDNs are thoroughly analyzed to gain an in-depth understanding of their systematic characteristics.The review introduces currently approved PDN products and further explores the opportunities and challenges in expanding their depth and breadth of application.Drug nanocrystals,drug-drug cocrystals(DDCs),antibody-drug conjugates(ADCs),and nanobodies represent the successful commercialization and widespread utilization of PDNs across various disease domains.Self-assembled pure drug nanoparticles(SAPDNPs),a next-generation product,still require extensive translational research.Challenges persist in transitioning from laboratory-scale production to mass manufacturing and overcoming the conversion threshold from laboratory findings to clinical applications.
文摘Journal overview:Journal of Mathematical Research with Applications(JMRA),formerly Journal of Mathematical Research and Exposition(JMRE)created in 1981,one of the transactions of China Society for Industrial and Applied Mathematics,is a home for original research papers of the highest quality in all areas of mathematics with applications.The target audience comprises:pure and applied mathematicians,graduate students in broad fields of sciences and technology,scientists and engineers interested in mathematics.
基金supported by the National Key R&D Program of China(2021YFA0716902)National Natural Science Foundation of China(NSFC)under contract number 42374149 and 42004119National Science and Technology Major Project(2024ZD1002907)。
文摘Seismic anisotropy has been extensively acknowledged as a crucial element that influences the wave propagation characteristic during wavefield simulation,inversion and imaging.Transversely isotropy(TI)and orthorhombic anisotropy(OA)are two typical categories of anisotropic media in exploration geophysics.In comparison of the elastic wave equations in both TI and OA media,pseudo-acoustic wave equations(PWEs)based on the acoustic assumption can markedly reduce computational cost and complexity.However,the presently available PWEs may experience SV-wave contamination and instability when anisotropic parameters cannot satisfy the approximated condition.Exploiting pure-mode wave equations can effectively resolve the above-mentioned issues and generate pure P-wave events without any artifacts.To further improve the computational accuracy and efficiency,we develop two novel pure qP-wave equations(PPEs)and illustrate the corresponding numerical solutions in the timespace domain for 3D tilted TI(TTI)and tilted OA(TOA)media.First,the rational polynomials are adopted to estimate the exact pure qP-wave dispersion relations,which contain complicated pseudo-differential operators with irrational forms.The polynomial coefficients are produced by applying a linear optimization algorithm to minimize the objective function difference between the expansion formula and the exact one.Then,the developed optimized PPEs are efficiently implemented using the finite-difference(FD)method in the time-space domain by introducing a scalar operator,which can help avoid the problem of spectral-based algorithms and other calculation burdens.Structures of the new equations are concise and corresponding implementation processes are straightforward.Phase velocity analyses indicate that our proposed optimized equations can lead to reliable approximation results.3D synthetic examples demonstrate that our proposed FD-based PPEs can produce accurate and stable P-wave responses,and effectively describe the wavefield features in complicated TTI and TOA media.
文摘Traveling through the vast snow-covered land of Xizang,the sacred plateau,one cannot help but be captivated by the natural grandeur:the azure skies with white clouds,snowy mountains,pure lakes,forests and grasslands where herds of sheep and yaks forage and stroll leisurely.
基金supported by the National Natural Science Foundation of China(No.52394204)by the Shanghai Municipal Science and Technology Major Project。
文摘With the development of renewable energy,electrochemical carbon dioxide reduction reaction(CO_(2)RR)has become a potential solution for achieving carbon neutrality.However,until now,due to issues with salt precipitate and regeneration of the electrolyte,this technology faces challenges such as difficulty in maintaining long-term stable operation and excessive costs.The pure water CO_(2)electrolyzers are believed to be the ultimate solution to eliminate the salt depreciation and electrolyte issues.This study develops an in-situ method tailored for CO_(2)reduction in pure water.By employing distribution of relaxation times(DRT)analysis and in-situ electrochemical active surface area(ECSA)measurements,we carried out a comprehensive investigation into the mass transport and electrochemical active surface area of gas diffusion electrodes(GDE)under pure water conditions.The maximum 89%CO selectivity and high selectivity(>80%)in the range of 0-300 mA/cm^(2)were achieved using commercial Ag nanoparticles by rational design of catalyst layer.We found that ionomers influence the CO_(2)electrolyzers performance via affecting local pH,GDE-membrane interface,and CO_(2)transport,while catalyst loading mainly influences the active area and CO_(2)transport.This work provides benchmark and insights for future pure water CO_(2)electrolyzers development.
