“Some foreign scholars have proposed that the new institutional economics can unify the social sciences.”Behind the institution is property,and the dual cognition of property is the obstacle.Property dualism comes f...“Some foreign scholars have proposed that the new institutional economics can unify the social sciences.”Behind the institution is property,and the dual cognition of property is the obstacle.Property dualism comes from the thought dualism in the western rationalism tradition.The transcendence of“property dualism”has experienced the stages of“labor value”and“reasonable value”,and the new era has ushered in the opportunity of the third transcendence.In the first two stages,“abundance”and“scarcity”are the root causes of the contradiction in the transcendence of property dualism.Marx’s basic property view of production relations(property relations)unifies the property views of Locke,Hume,and Commons.The three-dimensional property system model developed on the basis of Marx’s complex property view provides a theoretical tool for the third transcendence of property dualism.We have cracked the western rationalism dualism with Marx’s historical materialism and reconciled the property dualism with three-dimensional property system model.By this,we can continue to explore the potential of“institution unifying social sciences”.展开更多
By using the topological uniform descent,the necessary and sufficient conditions for which property(W_(E))and property(R)hold for bounded linear operators are given.As a consequence of the main result,the stability of...By using the topological uniform descent,the necessary and sufficient conditions for which property(W_(E))and property(R)hold for bounded linear operators are given.As a consequence of the main result,the stability of property(W_(E))and property(R)is studied,and a new judgement for operator functions that satisfy property(W_(E))and property(R)is discussed.展开更多
Friction stir lap welding of AA2195 Al-Li alloy and Ti alloy was conducted to investigate the formation,microstructure,and mechanical properties of the joints.Results show that under different welding parameters,with ...Friction stir lap welding of AA2195 Al-Li alloy and Ti alloy was conducted to investigate the formation,microstructure,and mechanical properties of the joints.Results show that under different welding parameters,with the decrease in welding heat input,the weld surface is smoother.The Ti/Al joint interface is flat without obvious Ti and Al mixed structure,and the hook structure is not formed under optimal parameters.Due to the enhanced breaking effect of the stirring head,the hook structural defects and intermetallic compounds are more likely to form at the Ti/Al interface at high rotational speed of 1000 r/min,thereby deteriorating the mechanical properties of joints.Decreasing the heat input is beneficial to hardness enhancement of the aluminum alloy in the weld nugget zone.Under the optimal parameters of rotation speed of 800 r/min and welding speed of 120 mm/min,the maximum tensile shear strength of joint is 289 N/mm.展开更多
In this paper,the property degradation micromechanism of Al-5.10Cu-0.65 Mg-0.8Mn(wt%)alloy induced by 0.5 wt%Fe minor addition was revealed by atomic-scale scanning transmission electron microscopy and energy-dispersi...In this paper,the property degradation micromechanism of Al-5.10Cu-0.65 Mg-0.8Mn(wt%)alloy induced by 0.5 wt%Fe minor addition was revealed by atomic-scale scanning transmission electron microscopy and energy-dispersive X-ray spectroscopy coupled with first-principles calculations.The results show that the Fe minor addition to the Al-Cu-Mg-Mn alloy leads to a slight reduction of grain size and the formation of coarse Al7Cu2Fe constituent particles.Fe tends to segregate into the T-phase dispersoids,θ'-,and S-phase precipitates by preferentially occupying Cu or Mn sites in these phase structures.The apparent Fe segregation contributes to an increase in stiffness of the T-phase and S-phase but decreased stiffness of theθ'phase.Formation of the coarse Al7Cu2Fe constituent particles and decreased stiffness of main precipitatesθ'containing Fe result in the degraded strength of the Al-Cu-Mg-Mn-Fe alloy.Further study reveals that corrosion resistance degradation of the Al-Cu-Mg-Mn-Fe alloy is associated with the increased width of precipitation free zones and consecutive grain boundary precipitates.The obtained results have significant implications for the usage of recycled Al alloys and the potential design strategies of high-performance alloys containing Fe.展开更多
Wigner-Ville distribution(WVD)is widely used in the field of signal processing due to its excellent time-frequency(TF)concentration.However,WVD is severely limited by the cross-term when working with multicomponent si...Wigner-Ville distribution(WVD)is widely used in the field of signal processing due to its excellent time-frequency(TF)concentration.However,WVD is severely limited by the cross-term when working with multicomponent signals.In this paper,we analyze the property differences between auto-term and cross-term in the one-dimensional sequence and the two-dimensional plane and approximate entropy and Rényi entropy are employed to describe them,respectively.Based on this information,we propose a new method to achieve adaptive cross-term removal by combining seeded region growing.Compared to other methods,the new method can achieve cross-term removal without decreasing the TF concentration of the auto-term.Simulation and experimental data processing results show that the method is adaptive and is not constrained by the type or distribution of signals.And it performs well in low signal-to-noise ratio environments.展开更多
Accurate prediction of molecular properties is crucial for selecting compounds with ideal properties and reducing the costs and risks of trials.Traditional methods based on manually crafted features and graph-based me...Accurate prediction of molecular properties is crucial for selecting compounds with ideal properties and reducing the costs and risks of trials.Traditional methods based on manually crafted features and graph-based methods have shown promising results in molecular property prediction.However,traditional methods rely on expert knowledge and often fail to capture the complex structures and interactions within molecules.Similarly,graph-based methods typically overlook the chemical structure and function hidden in molecular motifs and struggle to effectively integrate global and local molecular information.To address these limitations,we propose a novel fingerprint-enhanced hierarchical graph neural network(FH-GNN)for molecular property prediction that simultaneously learns information from hierarchical molecular graphs and fingerprints.The FH-GNN captures diverse hierarchical chemical information by applying directed message-passing neural networks(D-MPNN)on a hierarchical molecular graph that integrates atomic-level,motif-level,and graph-level information along with their relationships.Addi-tionally,we used an adaptive attention mechanism to balance the importance of hierarchical graphs and fingerprint features,creating a comprehensive molecular embedding that integrated hierarchical mo-lecular structures with domain knowledge.Experiments on eight benchmark datasets from MoleculeNet showed that FH-GNN outperformed the baseline models in both classification and regression tasks for molecular property prediction,validating its capability to comprehensively capture molecular informa-tion.By integrating molecular structure and chemical knowledge,FH-GNN provides a powerful tool for the accurate prediction of molecular properties and aids in the discovery of potential drug candidates.展开更多
The property IR was introduced by Friis and Rordam in 1996.They proved that any pair of almost commuting self-adjoint elements is norm close to a pair of exactly commuting self-adjoint elements in any C^(*)-algebras w...The property IR was introduced by Friis and Rordam in 1996.They proved that any pair of almost commuting self-adjoint elements is norm close to a pair of exactly commuting self-adjoint elements in any C^(*)-algebras with the property IR.In this paper,we will prove some permanence results for IR-algebras,approximate IR-algebras and local IR-algebras.Finally,we will also show that any pair of almost commuting self-adjoint elements is norm close to a pair of exactly commuting self-adjoint elements in any local IR-algebra.展开更多
Under the condition of solvothermal synthesis,the viologen ligand 1,1′-bis(3-carboxyphenyl)-(4,4′-bipyri-dine)dichloride(H_(2)bcbpy·2Cl)and KI are coordinated with the metal cadmium ions.A case of thermochromic...Under the condition of solvothermal synthesis,the viologen ligand 1,1′-bis(3-carboxyphenyl)-(4,4′-bipyri-dine)dichloride(H_(2)bcbpy·2Cl)and KI are coordinated with the metal cadmium ions.A case of thermochromic coor-dination polymer[Cd(bcbpy)I_(2)]·2H_(2)O(1)was constructed.Complex 1 displays a 1D chain structure and exhibits thermochromic behavior.Under different temperature stimulation,the complex(ground)slowly changed from green to yellow-green,and with the increase of temperature,the color of complex 1 gradually deepened,and finally became orange-yellow.Therefore,complex 1 was prepared as a thermochromic film.In addition,we also performed electrochemical tests on complex 1,which showed that the complex is a semiconductor material.CCDC:2391802.展开更多
With the rapid development of globalization and information technology,intellectual property has been one of the key drivers of economic growth,and the construction of intellectual property system has become an import...With the rapid development of globalization and information technology,intellectual property has been one of the key drivers of economic growth,and the construction of intellectual property system has become an important criterion for measuring the quality of business environment.This article is intended to explore the current status of intellectual property system construction in China,the challenges,and its relationship with the business environment,to propose the corresponding countermeasures and suggestions.The study finds that the legal system of intellectual property in China is gradually improving,and judicial and administrative protection are continuously strengthened.However,the challenges still remain such as frequent infringements,rights hard to protect and insufficient international cooperation.These issues not only affect the legitimate rights and interests of innovation entities,but also for the market fairness and the level of the business environment.Therefore,this article proposes that strengthening the perfection of the intellectual property legal system,enhancing intellectual property services and support capabilities,strengthening international cooperation and exchanges,and accelerating the cultivation of composite talents.It aims to provide theoretical references for the construction of intellectual property system and the optimization of the business environment,promote the high-quality development of economy and enhance the global competitiveness of the country.展开更多
This paper delves into the theoretical mechanisms of the electronic structure and optical properties of aluminum-based semiconductors(AlX,X=N,P,As,Sb)and indium-based semiconductors(InX,X=N,P,As,Sb)as potential materi...This paper delves into the theoretical mechanisms of the electronic structure and optical properties of aluminum-based semiconductors(AlX,X=N,P,As,Sb)and indium-based semiconductors(InX,X=N,P,As,Sb)as potential materials for optical devices.Band structure calculations reveal that,except for InSb,all other compounds are direct bandgap semiconductors,with AlN exhibiting a bandgap of 3.245 eV.The valence band maximum of these eight compounds primarily stems from the p-orbitals of Al/In and X.In contrast,the conduction band minimum is influenced by all orbitals,with a predominant contribution from the p-orbitals.The static dielectric constant increased with the expansion of the unit cell volume.Compared to AlX and InX with larger X atoms,AlN and InN showed broader absorption spectra in the near-ultraviolet region and higher photoelectric conductance.Regarding mechanical properties,AlN and InN displayed greater shear and bulk modulus than the other compounds.Moreover,among these eight crystal types,a higher modulus was associated with a lower light loss function value,indicating that AlN and InN have superior transmission efficiency and a wider spectral range in optoelectronic material applications.展开更多
A new cobalt(Ⅱ)-radical complex:[Co(im4-py)_(2)(PNB)_(2)](im4-py=2-(4'-pyridyl)-4,4,5,5-tetramethylimidazole-1-oxyl,HPNB=p-nitrobenzoic acid)has been synthesized and characterized by X-ray diffraction analysis,el...A new cobalt(Ⅱ)-radical complex:[Co(im4-py)_(2)(PNB)_(2)](im4-py=2-(4'-pyridyl)-4,4,5,5-tetramethylimidazole-1-oxyl,HPNB=p-nitrobenzoic acid)has been synthesized and characterized by X-ray diffraction analysis,elemental analysis,IR,and magnetic properties.X-ray diffraction analysis shows that the complex exists as mononuclear molecules and Co(Ⅱ)ion is four-coordinated with two radicals and two PNB-ligands.The magnetic susceptibility study indicates the complex exhibits weak ferromagnetic interactions between cobalt(Ⅱ)and im4-py radical.The magnetic property is explained by the magnetic and structure exchange mechanism.CCDC:976028.展开更多
This paper explores the recovery of block sparse signals in frame-based settings using the l_(2)/l_(q)-synthesis technique(0<q≤1).We propose a new null space property,referred to as block D-NSP_(q),which is based ...This paper explores the recovery of block sparse signals in frame-based settings using the l_(2)/l_(q)-synthesis technique(0<q≤1).We propose a new null space property,referred to as block D-NSP_(q),which is based on the dictionary D.We establish that matrices adhering to the block D-NSP_(q)condition are both necessary and sufficient for the exact recovery of block sparse signals via l_(2)/l_(q)-synthesis.Additionally,this condition is essential for the stable recovery of signals that are block-compressible with respect to D.This D-NSP_(q)property is identified as the first complete condition for successful signal recovery using l_(2)/l_(q)-synthesis.Furthermore,we assess the theoretical efficacy of the l2/lq-synthesis method under conditions of measurement noise.展开更多
Sc_(2)O_(3),as a host for solid-state laser gain materials,has advantage of high thermal conductivity and easy matching with activating ions,which is promising in high-power laser applications.Currently,Yb-doped Sc_(2...Sc_(2)O_(3),as a host for solid-state laser gain materials,has advantage of high thermal conductivity and easy matching with activating ions,which is promising in high-power laser applications.Currently,Yb-doped Sc_(2)O_(3) ceramics have been fabricated at very high sintering temperatures,but their optical quality and sintering process still need further improvement.In this work,5%Yb:Sc_(2)O_(3)(in mass)nano-powders were obtained by co-precipitation,and then transparent ceramics were fabricated by vacuum pre-sintering and hot isostatic pressing(HIP)post-treatment.The cubic Yb:Sc_(2)O_(3) nano-powders with good dispersity and an average crystallite of 29 nm were obtained.Influence of pre-sintering temperatures(1500-1700℃)on densification process,microstructure changes,and optical transmittance of Yb:Sc_(2)O_(3) ceramics was detected.Experimental data revealed that all samples have a uniform microstructure,while the average grain sizes increase with the increase of the sintering temperatures.Impressively,the optimum in-line transmittance of Yb:Sc_(2)O_(3) ceramics,pre-sintered at 1550℃after HIP post-treatment,reaches 78.1%(theoretical value of 80%)at 1100 nm.Spectroscopic properties of the Yb:Sc_(2)O_(3) ceramics reveal that the minimum population inversion parameterβ2 and the luminescence decay time of 5%Yb:Sc_(2)O_(3) ceramics are 0.041 and 0.49 ms,respectively,which demonstrate that the optical quality of the Yb:Sc_(2)O_(3) has been improved.Meanwhile,their best vacuum sintering temperature can be controlled down to a lower temperature(1550℃).In conclusion,Yb:Sc_(2)O_(3) nano-powders are successfully synthesized by co-precipitation method,and good optical quality transparent ceramics are fabricated by vacuum pre-sintering at 1550℃and HIP post-treatment.展开更多
A combination of hard(SiCP)and soft(fly ash)particulate reinforcements could be a strategy to enhance combination of multiple properties of Magnesium and its alloys which otherwise suffer from low stiffness,low wear r...A combination of hard(SiCP)and soft(fly ash)particulate reinforcements could be a strategy to enhance combination of multiple properties of Magnesium and its alloys which otherwise suffer from low stiffness,low wear resistance,and many other critical properties.However,at present a comprehensive and robust map correlating different properties in particle-reinforced composites is much lacking.In this work,an industrial grade AZ91 magnesium alloy reinforced with hard SiC and soft fly ash particles(with 3 vol.%each),has been prepared using stir casting followed by hot extrusion at 325℃with a ratio of 21.5.Microstructure of the hybrid composite was characterized using optical and scanning electron microscopes.The composite exhibited a reduction in average grain size from 13.6 to 7.1μm,concomitantly an increase in Vickers hardness from 73 to 111 HV.The tension-compression yield asymmetry ratios of the unreinforced alloy and hybrid composite were 1.165 and 0.976,respectively indicating higher yield strength for the composite under compressive load.The composite exhibited 76%improvement in damping capacity under time sweep mode,and 28%improvement at 423 K under temperature sweep mode.The tribological characteristics of the composite under dry sliding conditions at sliding speeds and loads in the range of 0.5 to 1.5 m s^(-1)and 10 to 30 N,respectively showed higher wear resistance than the unreinforced alloy.The composite showed 23%improvement in sliding wear resistance at a load of 20 N and a speed of 1 m s^(-1).Finally,efforts have been made to understand the influence of one property on the other by developing statistical property correlation maps from the properties obtained in this study and from the literature.These maps are expected to help in the design of hybrid Metal Matrix Composites for a variety of targeted applications in different sectors.展开更多
Creep is one of the most typical failure modes for the turbine blades of an aero-engine.The microstructure of the turbine blades after long-term service can be adjusted by rejuvenation heat treatment(RHT)to restore it...Creep is one of the most typical failure modes for the turbine blades of an aero-engine.The microstructure of the turbine blades after long-term service can be adjusted by rejuvenation heat treatment(RHT)to restore its creep properties.In this work,a series of RHT experiments were carried out on a directionally solidified(DS)nickel-based superalloy under different solution temperatures and primary aging temperatures based on the standard heat treatment(SHT)process parameters to investigate the mechanism of temperature influence on DS's microstructure after RHT.It is indicated that a more uniform microstructure can be obtained under higher solution temperatures and lower primary aging temperatures compared to the SHT process.Furthermore,by employing the image processing methods to quantify microstructural parameters,a comprehensive indicator parameter for the RHT effect(marked as Prej)was proposed to characterize the effects of RHT on DS superalloy's microstructure and creep property combined with the entropy weight method.Based on this,a regression model to describe the relationship between RHT process parameters and Prej was constructed by using the response surface methodology(RSM).It is revealed that the optimal solution temperature and primary aging temperature for this DS superalloy are 1283°C and 1095°C,respectively.Then the conclusion was validated through complete creep experiments on the DS superalloy,which showed the creep life after RHT reaches 95.5%of the SHT specimen,and the total life has increased by 20.6%.展开更多
Multifunctional semiconductors play an important role in developing advanced photoelectric technologies.In this work,based on an octahedral replacement strategy in chalcogenides,a new selenide semiconductor NaMn_(3)Ga...Multifunctional semiconductors play an important role in developing advanced photoelectric technologies.In this work,based on an octahedral replacement strategy in chalcogenides,a new selenide semiconductor NaMn_(3)Ga_(3)Se_(8)was rationally designed,and synthesized by the flux method.The compound crystallizes in the noncentrosymmetric(NCS)P_(6)space group,and is composed of unique prismatic[NaSe_(6)],octahedral[MnSe_(6)]and tetrahedral[GaSe_(4)]motifs,inheriting the stable three-dimensional framework built by the octahedral and tetrahedral units in the A^(Ⅰ)Mg_(3)^(Ⅱ)C_(3)^(Ⅲ)Q_(8)^(Ⅵ)family.NaMn_(3)Ga_(3)Se_(8)shows the largest known secondary nonlinear optical(NLO)response of~2.1×AgGaS_(2)(AGS)in the A^(Ⅰ)Mg_(3)^(Ⅱ)C_(3)^(Ⅲ)Q_(8)^(Ⅵ)family,and a high laser-induced damage threshold of~3.0×AGS.Meanwhile,the introduction of Mn2t with unpaired 3d electrons induces a strong red emission band(685–805 nm)under the excitation source of 496 nm,as well as a paramagnetic to antiferromagnetic(AFM)transition at 7.3 K.The results confirm that NaMn_(3)Ga_(3)Se_(8)possesses multifunctional features including significant NLO response,fluorescence emission and AFM properties,and illustrate that replacing octahedral units with approaching size and geometry(like[MgSe_(6)]and[MnSe_(6)])could be a feasible way to develop multifunctional chalcogenides.展开更多
In this paper,using the property of uniform Fredholm non-positive index of bounded linear operators,we give criteria for operators and their functions to possess property(ω),and several equivalent conditions for the ...In this paper,using the property of uniform Fredholm non-positive index of bounded linear operators,we give criteria for operators and their functions to possess property(ω),and several equivalent conditions for the stability of property(ω),and investigate the relationship between the stability of property(ω)and the(ω)-property of operator functions.展开更多
As a highly promising conductive polymer material,the synthesis method,structure regulation,and performance improvement of polyaniline(PANI)are hot research topics.In this work,the radiation-induced polymerization of ...As a highly promising conductive polymer material,the synthesis method,structure regulation,and performance improvement of polyaniline(PANI)are hot research topics.In this work,the radiation-induced polymerization of aniline in HNO_(3)solution was successfully achieved at room temperature without the use of chemical oxidants.Through the analysis of the radiation chemical reactions of inorganic acids and nitrate salt solutions,the characterization of the intermediate free radicals in the irradiated systems,and the influence of the pH of the solutions on the polymerization activity and product morphologies,the radiation-induced polymerization mechanism of aniline is discussed in detail and proposed.Only at a condition of[HNO_(3)]>[aniline],i.e.,pH<2.5,PANI can be successfully obtained underγ-ray radiation.The polymerization begins with the oxidation of aniline cations to aniline cation radicals by·NO_(3)generated by radiolysis reactions,and undergoes repeated three steps of monomer free radical recombination,deprotonation,and oxidation reaction of·NO_(3),thus forming a PANI macromolecule.In addition to the polymerization reaction,the aniline units are protonated and oxidized because of the strongly acidity and oxidation of the reaction system under γ-ray irradiation,which means that the molecular chain structure of the radiation-synthesized PANI can be regulated by pH,nitrate concentration,and irradiation conditions.Radiation-synthesized PANI has a moderate protonation and oxidation state,which can be used for the preparation of PANI supercapacitors with better electrochemical properties than those prepared by chemical oxidation under the same conditions.This work presents a new radiation-synthesis method and polymerization mechanism of PANI,which not only expands the application of radiation technique in the field of polymer synthesis,but also provides a new idea for the structural regulation and electrochemical property optimization of PANI.展开更多
Federated Graph Neural Networks (FedGNNs) have achieved significant success in representation learning for graph data, enabling collaborative training among multiple parties without sharing their raw graph data and so...Federated Graph Neural Networks (FedGNNs) have achieved significant success in representation learning for graph data, enabling collaborative training among multiple parties without sharing their raw graph data and solving the data isolation problem faced by centralized GNNs in data-sensitive scenarios. Despite the plethora of prior work on inference attacks against centralized GNNs, the vulnerability of FedGNNs to inference attacks has not yet been widely explored. It is still unclear whether the privacy leakage risks of centralized GNNs will also be introduced in FedGNNs. To bridge this gap, we present PIAFGNN, the first property inference attack (PIA) against FedGNNs. Compared with prior works on centralized GNNs, in PIAFGNN, the attacker can only obtain the global embedding gradient distributed by the central server. The attacker converts the task of stealing the target user’s local embeddings into a regression problem, using a regression model to generate the target graph node embeddings. By training shadow models and property classifiers, the attacker can infer the basic property information within the target graph that is of interest. Experiments on three benchmark graph datasets demonstrate that PIAFGNN achieves attack accuracy of over 70% in most cases, even approaching the attack accuracy of inference attacks against centralized GNNs in some instances, which is much higher than the attack accuracy of the random guessing method. Furthermore, we observe that common defense mechanisms cannot mitigate our attack without affecting the model’s performance on mainly classification tasks.展开更多
Zinc(Zn)-based materials show broad application prospects for bone repair due to their biodegradability and good biocompatibility.In particular,Zn metal foam has unique interconnected pore structure that facilitates i...Zinc(Zn)-based materials show broad application prospects for bone repair due to their biodegradability and good biocompatibility.In particular,Zn metal foam has unique interconnected pore structure that facilitates inward growth of new bone tissue,making it ideal candidates for orthopedic implants.However,pure Zn metal foam shows poor mechanical property,high degradation rate,and unsatisfactory osteogenic activity.Herein,Zinc-manganese(Zn-Mn)alloy foams were electrodeposited in Zn and Mn-containing electrolytes to overcome the concerns.The results showed that Mn could be incorporated into the foams in the form of MnZn_(13).Zn-Mn alloy foams showed better mechanical property and osteogenic activity as well as moderate degradation rate when compared with pure Zn metal foam.In addition,these properties could also be regulated by preparation process.The peak stress and osteogenic activity increased with deposition current(0.3‒0.5 A)and electrolyte pH(3‒5),but decreased with electrolyte temperature(20‒40℃),while the degradation rate exhibited opposite tendency,which suggests high deposition current and electrolyte pH and low electrolyte temperature can fabricate Zn-Mn alloy foam with favorable mechanical property,moderate degradation rate,and osteogenic activity.These findings provide a valuable reference for the design and fabrication of novel Zn-based biodegradable materials.展开更多
基金supported by the National Social Science Fund of China:“Research on the Philosophy of Property System of Modernization of China’s National Governance System and Governance Capacity”(Project Number:20BZX025).
文摘“Some foreign scholars have proposed that the new institutional economics can unify the social sciences.”Behind the institution is property,and the dual cognition of property is the obstacle.Property dualism comes from the thought dualism in the western rationalism tradition.The transcendence of“property dualism”has experienced the stages of“labor value”and“reasonable value”,and the new era has ushered in the opportunity of the third transcendence.In the first two stages,“abundance”and“scarcity”are the root causes of the contradiction in the transcendence of property dualism.Marx’s basic property view of production relations(property relations)unifies the property views of Locke,Hume,and Commons.The three-dimensional property system model developed on the basis of Marx’s complex property view provides a theoretical tool for the third transcendence of property dualism.We have cracked the western rationalism dualism with Marx’s historical materialism and reconciled the property dualism with three-dimensional property system model.By this,we can continue to explore the potential of“institution unifying social sciences”.
基金Supported by the 2021 General Special Scientific Research Project of the Education Department of Shaanxi Provincial Government(21JK0637)the Science and Technology Planning Project of Weinan Science and Technology Bureau(2022ZDYFJH-11)the 2021 Talent Project of Weinan Normal University(2021RC16)。
文摘By using the topological uniform descent,the necessary and sufficient conditions for which property(W_(E))and property(R)hold for bounded linear operators are given.As a consequence of the main result,the stability of property(W_(E))and property(R)is studied,and a new judgement for operator functions that satisfy property(W_(E))and property(R)is discussed.
基金National Natural Science Foundation of China(52275349)Key Research and Development Program of Shandong Province(2021ZLGX01)。
文摘Friction stir lap welding of AA2195 Al-Li alloy and Ti alloy was conducted to investigate the formation,microstructure,and mechanical properties of the joints.Results show that under different welding parameters,with the decrease in welding heat input,the weld surface is smoother.The Ti/Al joint interface is flat without obvious Ti and Al mixed structure,and the hook structure is not formed under optimal parameters.Due to the enhanced breaking effect of the stirring head,the hook structural defects and intermetallic compounds are more likely to form at the Ti/Al interface at high rotational speed of 1000 r/min,thereby deteriorating the mechanical properties of joints.Decreasing the heat input is beneficial to hardness enhancement of the aluminum alloy in the weld nugget zone.Under the optimal parameters of rotation speed of 800 r/min and welding speed of 120 mm/min,the maximum tensile shear strength of joint is 289 N/mm.
基金supported by the National Natural Science Foundation of China(Nos.U20A20274 and 52061003)the Natural Science Foundation of Yunnan Province(No.202301AT070209)the Science and Technology Major Project of Yunnan Province(No.202102AG050017).
文摘In this paper,the property degradation micromechanism of Al-5.10Cu-0.65 Mg-0.8Mn(wt%)alloy induced by 0.5 wt%Fe minor addition was revealed by atomic-scale scanning transmission electron microscopy and energy-dispersive X-ray spectroscopy coupled with first-principles calculations.The results show that the Fe minor addition to the Al-Cu-Mg-Mn alloy leads to a slight reduction of grain size and the formation of coarse Al7Cu2Fe constituent particles.Fe tends to segregate into the T-phase dispersoids,θ'-,and S-phase precipitates by preferentially occupying Cu or Mn sites in these phase structures.The apparent Fe segregation contributes to an increase in stiffness of the T-phase and S-phase but decreased stiffness of theθ'phase.Formation of the coarse Al7Cu2Fe constituent particles and decreased stiffness of main precipitatesθ'containing Fe result in the degraded strength of the Al-Cu-Mg-Mn-Fe alloy.Further study reveals that corrosion resistance degradation of the Al-Cu-Mg-Mn-Fe alloy is associated with the increased width of precipitation free zones and consecutive grain boundary precipitates.The obtained results have significant implications for the usage of recycled Al alloys and the potential design strategies of high-performance alloys containing Fe.
基金Supported by the National Natural Science Foundation of China(62201171).
文摘Wigner-Ville distribution(WVD)is widely used in the field of signal processing due to its excellent time-frequency(TF)concentration.However,WVD is severely limited by the cross-term when working with multicomponent signals.In this paper,we analyze the property differences between auto-term and cross-term in the one-dimensional sequence and the two-dimensional plane and approximate entropy and Rényi entropy are employed to describe them,respectively.Based on this information,we propose a new method to achieve adaptive cross-term removal by combining seeded region growing.Compared to other methods,the new method can achieve cross-term removal without decreasing the TF concentration of the auto-term.Simulation and experimental data processing results show that the method is adaptive and is not constrained by the type or distribution of signals.And it performs well in low signal-to-noise ratio environments.
基金supported by Macao Science and Technology Development Fund,Macao SAR,China(Grant No.:0043/2023/AFJ)the National Natural Science Foundation of China(Grant No.:22173038)Macao Polytechnic University,Macao SAR,China(Grant No.:RP/FCA-01/2022).
文摘Accurate prediction of molecular properties is crucial for selecting compounds with ideal properties and reducing the costs and risks of trials.Traditional methods based on manually crafted features and graph-based methods have shown promising results in molecular property prediction.However,traditional methods rely on expert knowledge and often fail to capture the complex structures and interactions within molecules.Similarly,graph-based methods typically overlook the chemical structure and function hidden in molecular motifs and struggle to effectively integrate global and local molecular information.To address these limitations,we propose a novel fingerprint-enhanced hierarchical graph neural network(FH-GNN)for molecular property prediction that simultaneously learns information from hierarchical molecular graphs and fingerprints.The FH-GNN captures diverse hierarchical chemical information by applying directed message-passing neural networks(D-MPNN)on a hierarchical molecular graph that integrates atomic-level,motif-level,and graph-level information along with their relationships.Addi-tionally,we used an adaptive attention mechanism to balance the importance of hierarchical graphs and fingerprint features,creating a comprehensive molecular embedding that integrated hierarchical mo-lecular structures with domain knowledge.Experiments on eight benchmark datasets from MoleculeNet showed that FH-GNN outperformed the baseline models in both classification and regression tasks for molecular property prediction,validating its capability to comprehensively capture molecular informa-tion.By integrating molecular structure and chemical knowledge,FH-GNN provides a powerful tool for the accurate prediction of molecular properties and aids in the discovery of potential drug candidates.
基金Supported by NSFC(No.11401256)Scientific Research Fund of Zhejiang Provincial Education Department(No.Y202249575)Zhejiang Provincial NSF(No.LQ13A010016).
文摘The property IR was introduced by Friis and Rordam in 1996.They proved that any pair of almost commuting self-adjoint elements is norm close to a pair of exactly commuting self-adjoint elements in any C^(*)-algebras with the property IR.In this paper,we will prove some permanence results for IR-algebras,approximate IR-algebras and local IR-algebras.Finally,we will also show that any pair of almost commuting self-adjoint elements is norm close to a pair of exactly commuting self-adjoint elements in any local IR-algebra.
文摘Under the condition of solvothermal synthesis,the viologen ligand 1,1′-bis(3-carboxyphenyl)-(4,4′-bipyri-dine)dichloride(H_(2)bcbpy·2Cl)and KI are coordinated with the metal cadmium ions.A case of thermochromic coor-dination polymer[Cd(bcbpy)I_(2)]·2H_(2)O(1)was constructed.Complex 1 displays a 1D chain structure and exhibits thermochromic behavior.Under different temperature stimulation,the complex(ground)slowly changed from green to yellow-green,and with the increase of temperature,the color of complex 1 gradually deepened,and finally became orange-yellow.Therefore,complex 1 was prepared as a thermochromic film.In addition,we also performed electrochemical tests on complex 1,which showed that the complex is a semiconductor material.CCDC:2391802.
基金Guizhou Provincial University Humanities and Social Sciences Research Project in 2024"Enhancing the Development of New Productive Forces through University Technological Innovation and Intellectual Property Management"(2024RW256)Guizhou University of Commerce Research Project in 2022"Study on the Ideas and Pathways to Drive Agricultural Powerhouse through Digital Economy"(2022XJZX315)。
文摘With the rapid development of globalization and information technology,intellectual property has been one of the key drivers of economic growth,and the construction of intellectual property system has become an important criterion for measuring the quality of business environment.This article is intended to explore the current status of intellectual property system construction in China,the challenges,and its relationship with the business environment,to propose the corresponding countermeasures and suggestions.The study finds that the legal system of intellectual property in China is gradually improving,and judicial and administrative protection are continuously strengthened.However,the challenges still remain such as frequent infringements,rights hard to protect and insufficient international cooperation.These issues not only affect the legitimate rights and interests of innovation entities,but also for the market fairness and the level of the business environment.Therefore,this article proposes that strengthening the perfection of the intellectual property legal system,enhancing intellectual property services and support capabilities,strengthening international cooperation and exchanges,and accelerating the cultivation of composite talents.It aims to provide theoretical references for the construction of intellectual property system and the optimization of the business environment,promote the high-quality development of economy and enhance the global competitiveness of the country.
文摘This paper delves into the theoretical mechanisms of the electronic structure and optical properties of aluminum-based semiconductors(AlX,X=N,P,As,Sb)and indium-based semiconductors(InX,X=N,P,As,Sb)as potential materials for optical devices.Band structure calculations reveal that,except for InSb,all other compounds are direct bandgap semiconductors,with AlN exhibiting a bandgap of 3.245 eV.The valence band maximum of these eight compounds primarily stems from the p-orbitals of Al/In and X.In contrast,the conduction band minimum is influenced by all orbitals,with a predominant contribution from the p-orbitals.The static dielectric constant increased with the expansion of the unit cell volume.Compared to AlX and InX with larger X atoms,AlN and InN showed broader absorption spectra in the near-ultraviolet region and higher photoelectric conductance.Regarding mechanical properties,AlN and InN displayed greater shear and bulk modulus than the other compounds.Moreover,among these eight crystal types,a higher modulus was associated with a lower light loss function value,indicating that AlN and InN have superior transmission efficiency and a wider spectral range in optoelectronic material applications.
文摘A new cobalt(Ⅱ)-radical complex:[Co(im4-py)_(2)(PNB)_(2)](im4-py=2-(4'-pyridyl)-4,4,5,5-tetramethylimidazole-1-oxyl,HPNB=p-nitrobenzoic acid)has been synthesized and characterized by X-ray diffraction analysis,elemental analysis,IR,and magnetic properties.X-ray diffraction analysis shows that the complex exists as mononuclear molecules and Co(Ⅱ)ion is four-coordinated with two radicals and two PNB-ligands.The magnetic susceptibility study indicates the complex exhibits weak ferromagnetic interactions between cobalt(Ⅱ)and im4-py radical.The magnetic property is explained by the magnetic and structure exchange mechanism.CCDC:976028.
基金Supported by The Featured Innovation Projects of the General University of Guangdong Province(2023KTSCX096)The Special Projects in Key Areas of Guangdong Province(ZDZX1088)Research Team Project of Guangdong University of Education(2024KYCXTD018)。
文摘This paper explores the recovery of block sparse signals in frame-based settings using the l_(2)/l_(q)-synthesis technique(0<q≤1).We propose a new null space property,referred to as block D-NSP_(q),which is based on the dictionary D.We establish that matrices adhering to the block D-NSP_(q)condition are both necessary and sufficient for the exact recovery of block sparse signals via l_(2)/l_(q)-synthesis.Additionally,this condition is essential for the stable recovery of signals that are block-compressible with respect to D.This D-NSP_(q)property is identified as the first complete condition for successful signal recovery using l_(2)/l_(q)-synthesis.Furthermore,we assess the theoretical efficacy of the l2/lq-synthesis method under conditions of measurement noise.
基金National Key R&D Program of China(2023YFE3812005)International Partnership Program of Chinese Academy of Sciences(121631KYSB20200039)+1 种基金National Center for Research and Development(WPC2/1/SCAPOL/2021)Chinese Academy of Sciences President’s International Fellowship Initiative(2024VEA0005,2024VEA0014)。
文摘Sc_(2)O_(3),as a host for solid-state laser gain materials,has advantage of high thermal conductivity and easy matching with activating ions,which is promising in high-power laser applications.Currently,Yb-doped Sc_(2)O_(3) ceramics have been fabricated at very high sintering temperatures,but their optical quality and sintering process still need further improvement.In this work,5%Yb:Sc_(2)O_(3)(in mass)nano-powders were obtained by co-precipitation,and then transparent ceramics were fabricated by vacuum pre-sintering and hot isostatic pressing(HIP)post-treatment.The cubic Yb:Sc_(2)O_(3) nano-powders with good dispersity and an average crystallite of 29 nm were obtained.Influence of pre-sintering temperatures(1500-1700℃)on densification process,microstructure changes,and optical transmittance of Yb:Sc_(2)O_(3) ceramics was detected.Experimental data revealed that all samples have a uniform microstructure,while the average grain sizes increase with the increase of the sintering temperatures.Impressively,the optimum in-line transmittance of Yb:Sc_(2)O_(3) ceramics,pre-sintered at 1550℃after HIP post-treatment,reaches 78.1%(theoretical value of 80%)at 1100 nm.Spectroscopic properties of the Yb:Sc_(2)O_(3) ceramics reveal that the minimum population inversion parameterβ2 and the luminescence decay time of 5%Yb:Sc_(2)O_(3) ceramics are 0.041 and 0.49 ms,respectively,which demonstrate that the optical quality of the Yb:Sc_(2)O_(3) has been improved.Meanwhile,their best vacuum sintering temperature can be controlled down to a lower temperature(1550℃).In conclusion,Yb:Sc_(2)O_(3) nano-powders are successfully synthesized by co-precipitation method,and good optical quality transparent ceramics are fabricated by vacuum pre-sintering at 1550℃and HIP post-treatment.
文摘A combination of hard(SiCP)and soft(fly ash)particulate reinforcements could be a strategy to enhance combination of multiple properties of Magnesium and its alloys which otherwise suffer from low stiffness,low wear resistance,and many other critical properties.However,at present a comprehensive and robust map correlating different properties in particle-reinforced composites is much lacking.In this work,an industrial grade AZ91 magnesium alloy reinforced with hard SiC and soft fly ash particles(with 3 vol.%each),has been prepared using stir casting followed by hot extrusion at 325℃with a ratio of 21.5.Microstructure of the hybrid composite was characterized using optical and scanning electron microscopes.The composite exhibited a reduction in average grain size from 13.6 to 7.1μm,concomitantly an increase in Vickers hardness from 73 to 111 HV.The tension-compression yield asymmetry ratios of the unreinforced alloy and hybrid composite were 1.165 and 0.976,respectively indicating higher yield strength for the composite under compressive load.The composite exhibited 76%improvement in damping capacity under time sweep mode,and 28%improvement at 423 K under temperature sweep mode.The tribological characteristics of the composite under dry sliding conditions at sliding speeds and loads in the range of 0.5 to 1.5 m s^(-1)and 10 to 30 N,respectively showed higher wear resistance than the unreinforced alloy.The composite showed 23%improvement in sliding wear resistance at a load of 20 N and a speed of 1 m s^(-1).Finally,efforts have been made to understand the influence of one property on the other by developing statistical property correlation maps from the properties obtained in this study and from the literature.These maps are expected to help in the design of hybrid Metal Matrix Composites for a variety of targeted applications in different sectors.
基金Supported by National Natural Science Foundation of China(Grant No.52275142)Science Center for Gas Turbine Project(Grant Nos.P2022-AIII-003-001,P2022-B-III-005-001)+1 种基金National Science and Technology Major Project(Grant Nos.J2019-IV-0009-0077,Y2022-IV-0002-0019,J2019-IV-0008-0076)National Basic Scientific Research Project(Grant No.JCKY2021601B204)。
文摘Creep is one of the most typical failure modes for the turbine blades of an aero-engine.The microstructure of the turbine blades after long-term service can be adjusted by rejuvenation heat treatment(RHT)to restore its creep properties.In this work,a series of RHT experiments were carried out on a directionally solidified(DS)nickel-based superalloy under different solution temperatures and primary aging temperatures based on the standard heat treatment(SHT)process parameters to investigate the mechanism of temperature influence on DS's microstructure after RHT.It is indicated that a more uniform microstructure can be obtained under higher solution temperatures and lower primary aging temperatures compared to the SHT process.Furthermore,by employing the image processing methods to quantify microstructural parameters,a comprehensive indicator parameter for the RHT effect(marked as Prej)was proposed to characterize the effects of RHT on DS superalloy's microstructure and creep property combined with the entropy weight method.Based on this,a regression model to describe the relationship between RHT process parameters and Prej was constructed by using the response surface methodology(RSM).It is revealed that the optimal solution temperature and primary aging temperature for this DS superalloy are 1283°C and 1095°C,respectively.Then the conclusion was validated through complete creep experiments on the DS superalloy,which showed the creep life after RHT reaches 95.5%of the SHT specimen,and the total life has increased by 20.6%.
基金supported by the Natural Science Foundation of the Xinjiang Uygur Autonomous Region(2024D01E30)the Strategic Priority Research Program of the Chinese Academy of Sciences(XDB0880000)+1 种基金the Open Fund of the Anhui Key Laboratory of Photonic Materials and Devices(AHKL2024KF02)the National Natural Science Foundation of China(22475234,22335007,22193044 and 22361132544).
文摘Multifunctional semiconductors play an important role in developing advanced photoelectric technologies.In this work,based on an octahedral replacement strategy in chalcogenides,a new selenide semiconductor NaMn_(3)Ga_(3)Se_(8)was rationally designed,and synthesized by the flux method.The compound crystallizes in the noncentrosymmetric(NCS)P_(6)space group,and is composed of unique prismatic[NaSe_(6)],octahedral[MnSe_(6)]and tetrahedral[GaSe_(4)]motifs,inheriting the stable three-dimensional framework built by the octahedral and tetrahedral units in the A^(Ⅰ)Mg_(3)^(Ⅱ)C_(3)^(Ⅲ)Q_(8)^(Ⅵ)family.NaMn_(3)Ga_(3)Se_(8)shows the largest known secondary nonlinear optical(NLO)response of~2.1×AgGaS_(2)(AGS)in the A^(Ⅰ)Mg_(3)^(Ⅱ)C_(3)^(Ⅲ)Q_(8)^(Ⅵ)family,and a high laser-induced damage threshold of~3.0×AGS.Meanwhile,the introduction of Mn2t with unpaired 3d electrons induces a strong red emission band(685–805 nm)under the excitation source of 496 nm,as well as a paramagnetic to antiferromagnetic(AFM)transition at 7.3 K.The results confirm that NaMn_(3)Ga_(3)Se_(8)possesses multifunctional features including significant NLO response,fluorescence emission and AFM properties,and illustrate that replacing octahedral units with approaching size and geometry(like[MgSe_(6)]and[MnSe_(6)])could be a feasible way to develop multifunctional chalcogenides.
基金supported by the National Natural Science Foundation of China(No.11501419)the Nature Science Basic Research Plan in Shaanxi Province of China(No.2021JM-519)。
文摘In this paper,using the property of uniform Fredholm non-positive index of bounded linear operators,we give criteria for operators and their functions to possess property(ω),and several equivalent conditions for the stability of property(ω),and investigate the relationship between the stability of property(ω)and the(ω)-property of operator functions.
基金financially supported by the National Natural Science Foundation of China(Nos.51973205 and 51773189)the Fundamental Research Funds for the Central Universities(Nos.WK9110000066,WK345000005 and WK345000006).
文摘As a highly promising conductive polymer material,the synthesis method,structure regulation,and performance improvement of polyaniline(PANI)are hot research topics.In this work,the radiation-induced polymerization of aniline in HNO_(3)solution was successfully achieved at room temperature without the use of chemical oxidants.Through the analysis of the radiation chemical reactions of inorganic acids and nitrate salt solutions,the characterization of the intermediate free radicals in the irradiated systems,and the influence of the pH of the solutions on the polymerization activity and product morphologies,the radiation-induced polymerization mechanism of aniline is discussed in detail and proposed.Only at a condition of[HNO_(3)]>[aniline],i.e.,pH<2.5,PANI can be successfully obtained underγ-ray radiation.The polymerization begins with the oxidation of aniline cations to aniline cation radicals by·NO_(3)generated by radiolysis reactions,and undergoes repeated three steps of monomer free radical recombination,deprotonation,and oxidation reaction of·NO_(3),thus forming a PANI macromolecule.In addition to the polymerization reaction,the aniline units are protonated and oxidized because of the strongly acidity and oxidation of the reaction system under γ-ray irradiation,which means that the molecular chain structure of the radiation-synthesized PANI can be regulated by pH,nitrate concentration,and irradiation conditions.Radiation-synthesized PANI has a moderate protonation and oxidation state,which can be used for the preparation of PANI supercapacitors with better electrochemical properties than those prepared by chemical oxidation under the same conditions.This work presents a new radiation-synthesis method and polymerization mechanism of PANI,which not only expands the application of radiation technique in the field of polymer synthesis,but also provides a new idea for the structural regulation and electrochemical property optimization of PANI.
基金supported by the National Natural Science Foundation of China(Nos.62176122 and 62061146002).
文摘Federated Graph Neural Networks (FedGNNs) have achieved significant success in representation learning for graph data, enabling collaborative training among multiple parties without sharing their raw graph data and solving the data isolation problem faced by centralized GNNs in data-sensitive scenarios. Despite the plethora of prior work on inference attacks against centralized GNNs, the vulnerability of FedGNNs to inference attacks has not yet been widely explored. It is still unclear whether the privacy leakage risks of centralized GNNs will also be introduced in FedGNNs. To bridge this gap, we present PIAFGNN, the first property inference attack (PIA) against FedGNNs. Compared with prior works on centralized GNNs, in PIAFGNN, the attacker can only obtain the global embedding gradient distributed by the central server. The attacker converts the task of stealing the target user’s local embeddings into a regression problem, using a regression model to generate the target graph node embeddings. By training shadow models and property classifiers, the attacker can infer the basic property information within the target graph that is of interest. Experiments on three benchmark graph datasets demonstrate that PIAFGNN achieves attack accuracy of over 70% in most cases, even approaching the attack accuracy of inference attacks against centralized GNNs in some instances, which is much higher than the attack accuracy of the random guessing method. Furthermore, we observe that common defense mechanisms cannot mitigate our attack without affecting the model’s performance on mainly classification tasks.
基金supported by the Key Research and Development Program of Shanxi Province(202102130501007)the Natural Science Foundation of Shanxi Province(202403021212109,202203021211173)the Scientific and Technological Innovation Programs of Higher Education Institutions in Shanxi(2024L039).
文摘Zinc(Zn)-based materials show broad application prospects for bone repair due to their biodegradability and good biocompatibility.In particular,Zn metal foam has unique interconnected pore structure that facilitates inward growth of new bone tissue,making it ideal candidates for orthopedic implants.However,pure Zn metal foam shows poor mechanical property,high degradation rate,and unsatisfactory osteogenic activity.Herein,Zinc-manganese(Zn-Mn)alloy foams were electrodeposited in Zn and Mn-containing electrolytes to overcome the concerns.The results showed that Mn could be incorporated into the foams in the form of MnZn_(13).Zn-Mn alloy foams showed better mechanical property and osteogenic activity as well as moderate degradation rate when compared with pure Zn metal foam.In addition,these properties could also be regulated by preparation process.The peak stress and osteogenic activity increased with deposition current(0.3‒0.5 A)and electrolyte pH(3‒5),but decreased with electrolyte temperature(20‒40℃),while the degradation rate exhibited opposite tendency,which suggests high deposition current and electrolyte pH and low electrolyte temperature can fabricate Zn-Mn alloy foam with favorable mechanical property,moderate degradation rate,and osteogenic activity.These findings provide a valuable reference for the design and fabrication of novel Zn-based biodegradable materials.
