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Mechanical Behavior and Microstructure Evolution during Tensile Deformation of Twinning Induced Plasticity Steel Processed by Warm Forgings

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Journal of Wuhan University of Technology(Materials science) 2024年第2期39卷 417-424页

作者：王文 ZHAO Modi WANG Xingfu 汪聃韩福生 School of Aerospace and Mechanical Engineering Flight college Changzhou Institute of TechnologyChangzhou 213032China Key Laboratory of Materials physics Institute of Solid State PhysicsChinese Academy of SciencesHefei 230031China School of physics and electronic {2. Yan’an UniversityYan’an 716000China

The mechanical behavior and microstructural evolution of an Fe-30Mn-3Al-3Si twinninginduced plasticity(TWIP)steel processed using warm forging was *** is found that steel processed via warm forging improves comprehensive mechanical properties compared to the TWIP steel processed via cold rolling,with a high tensile strength(R_(m))of 793 MPa,a yield strength(R_(P))of 682.MPa,an extremely large R_(P)/R_(m)ratio as high as 0.86 as well as an excellent elongation rate of 46.8%.The microstructure observation demonstrates that steel processed by warm forging consists of large and elongated grains together with fine,equiaxed *** micro-defect configurations were also observed within the steel,including dense dislocation networks and a few coarse deformation *** the plastic deformation proceeds,the densities of dislocations and deformation twins significantly ***,a great number of slip lines could be observed in the elongated *** findings reveal that a much more dramatic interaction between microstructural defect and dislocations glide takes place in the forging sample,wherein the fine and equiaxed grains propagated dislocations more rapidly,together with initial defect configurations,are responsible for enhanced strength ***,larger,elongated grains with more prevalently activated deformation twins result in high plasticity.

关键词： TWIP steel twinning mechanical property deformation mechanism microstructure

Emerging direct current triboelectric nanogenerator for high-entropy mechanical energy harvesting

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science China(Technological sciences) 2024年第5期67卷 1297-1316页

作者： CHEN Jie GUO RuiLong GUO HengYu college of physics and {2. Engineering Chongqing Normal UniversityChongqing 401331China Department of Applied physics Chongqing UniversityChongqing 401331China

In the era of the Internet of Things(IoT),the provision of sustainable power to distributed,mobile,and low-power-consumption electronic devices is a critical *** overcome this challenge,the triboelectric nanogenerator(TENG),a highly efficient high-entropy mechanical energy harvesting device,was developed in *** device enables the direct conversion of irregular and low-frequency mechanical energy into pulsed alternating current(AC)***,the incompatibility of most electronic devices with AC signals necessitates rectifier circuits or generators that deliver direct current(DC)*** recent years,DC-TENGs have undergone extensive development,achieving significant milestones in various application fields while also facing crucial challenges that require *** this review,three categories of DC-TENG devices with distinct operating mechanisms are comprehensively explored:multiphase coupling,mechanical rectification,and air *** typical structures and working mechanisms are thoroughly discussed,and specific output performance limitations,along with corresponding optimization strategies,are ***,the applications of DC-TENGs in various scenarios are ***,the challenges faced by DC-TENGs and potential solutions are analyzed to guide further advancements in this technology.

关键词： TENG direct current working mechanisms output performance limitations optimization strategies

Nonlinear Seebeck and Peltier effects in a Majorana nanowire coupled to leads

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Chinese physics B 2024年第7期33卷 547-552页

作者：迟锋刘佳付振国刘黎明易子川 School of electronic and information Engineering UESTC of ChinaZhongshan InstituteZhongshan 528400China School of science Inner Mongolia University of Science and TechnologyBaotou 014010China Institute of Applied physics and Computational Mathematics Beijing 100088China

We theoretically study nonlinear thermoelectric transport through a topological superconductor nanowire hosting Majorana bound states(MBSs) at its two ends, a system named as Majorana nanowire(MNW). We consider that the MNW is coupled to the left and right normal metallic leads subjected to either bias voltage or temperature gradient. We focus our attention on the sign change of nonlinear Seebeck and Peltier coefficients induced by mechanisms related to the MBSs, by which the possible existence of MBSs might be proved. Our results show that for a fixed temperature difference between the two leads, the sign of the nonlinear Seebeck coefficient(thermopower) can be reversed by changing the overlap amplitude between the MBSs or the system equilibrium temperature, which are similar to the cases in linear response regime. By optimizing the MBS–MBS interaction amplitude and system equilibrium temperature, we find that the temperature difference may also induce sign change of the nonlinear thermopower. For zero temperature difference and finite bias voltage, both the sign and magnitude of nonlinear Peltier coefficient can be adjusted by changing the bias voltage or overlap amplitude between the MBSs. In the presence of both bias voltage and temperature difference, we show that the electrical current at zero Fermi level and the states induced by overlap between the MBSs keep unchanged, regardless of the amplitude of temperature difference. We also find that the direction of the heat current driven by bias voltage may be changed by weak temperature difference.

关键词： quantum dot nonlinear Seebeck coefficient Peltier coefficient Majorana bound states sign change

Solution-processed rare-earth thulium oxide with high permittivity for low-voltage transistor and inverters applications

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Journal of Rare Earths 2024年第8期42卷 1604-1609,I0007页

作者： Daiming Liu Fei Wang Yongtao Zhang Ya'nan Ding Shandong Engineering Laboratory for Preparation and Application of High-performance Carbon-Materials College of Electromechanical EngineeringQingdao University of Science&TechnologyQingdao266061China college of electronic and {2. Engineering Shandong University of Science and TechnologyQingdao266590China

The use of high-permittivity(high-k) thin films as gate dielectrics is essential in the development of lowpower electronics,In this work,rare-earth thulium oxide(Tm_(2.O_(3)) thin films were prepared by a facile solution process and annealed at various temperatures from 400 to 700℃.The evolution of the physical and dielectric properties of Tm_(2.O_(3) thin film with annealing temperature was *** is demonstrated that the Tm_(2.O_(3) thin film annealed at 600℃ exhibits the optimal performance,including a low leakage current of 3×10^(-10) A/cm^(2.,a large areal capacitance of 2.0 nF/cm^(2. at 100 Hz,and a high permittivity value of *** Tm_(2.O_(3) thin film as a gate insulator was integrated into the thin film transistor(TFT) employing In_(2.O_(3)-based semiconducting *** In_(2.O_(3) TFT with 600℃-annealed Tm_(2.O_(3) dielectric exhibits the superior perfo rmance,with a high I_(on)/I_(off) of 1.65×10^(7),a small subthre shold swing(SS) value of 0.2.V/dec,a V_(TH) of+1.8 V,and a mobility of 1.68 cm^(2./(V·s).Furthermore,an inverter constructed by connecting the TFT with a resistor exhibits full-swing *** work provides a facile and appealing method for preparing the high-k Tm_(2.O_(3) thin films as alternative gate dielectrics with the potential for use in low-power electronics and logic circuit applications.

关键词： Rare earths Tm_(2.O_(3) Dielectric Transistor Inverter

Dependence of Rydberg-atom-based sensor performance on different Rydberg atom populations in one atomic-vapor cell

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Chinese physics B 2024年第2期33卷 365-370页

作者：武博姚佳伟吴逢川安强付云起 college of electronic {2. and Technology National University of Defense TechnologyChangsha 410073China

The atomic-vapor cell is a vital component for Rydberg atomic microwave sensors,and impacts on overall capability of Rydberg ***,the conventional analysis approach on effect of vapor-cell length contains two implicit assumptions,that is,the same atomic population density and buffer gas pressure,which make it unable to accurately capture actual response about effect of Rydberg-atom-based sensor performance on different Rydberg atom ***,utilizing a stepped cesium atomic-vapor cell with five different dimensions at the same atomic population density and buffer gas pressure,the height and full width at half maximum of electromagnetically induced transparency(EIT)signal,and the sensitivity of the atomic superheterodyne sensor are comprehensively investigated under conditions of the same Rabi frequencies(saturated laser power).It is identified that EIT signal height is proportional to the cell length,full width at half maximum and sensitivity grow with the increment of cell length to a certain *** the coherent integration signal theory and atomic linear expansion coefficient method,theoretical analysis of the EIT height and sensitivity are further *** results could shed new light on understanding and design of ultrahigh-sensitivity Rydberg atomic microwave sensors and find promising applications in quantum measurement,communication,and imaging.

关键词： Rydberg atom population Rydberg-atom-based receiver stepped atomic-vapor cell

Image encryption algorithm based on multiple chaotic systems and improved Joseph block scrambling

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Chinese physics B 2024年第10期33卷 248-257页

作者： Dingkang Mou Yumin Dong college of Computer and information {2. Chongqing Normal UniversityChongqing 400047China

With the rapid development of digital information technology,images are increasingly used in various *** ensure the security of image data,prevent unauthorized tampering and leakage,maintain personal privacy,and protect intellectual property rights,this study proposes an innovative color image encryption ***,the Mersenne Twister algorithm is utilized to generate high-quality pseudo-random numbers,establishing a robust basis for subsequent ***,two distinct chaotic systems,the autonomous non-Hamiltonian chaotic system and the tentlogistic-cosine chaotic mapping,are employed to produce chaotic random *** chaotic sequences are used to control the encoding and decoding process of the DNA,effectively scrambling the image ***,the complexity of the encryption process is enhanced through improved Joseph block *** experimental verification,research,and analysis,the average value of the information entropy test data reaches as high as ***,the average value of the number of pixels change rate(NPCR)test data is 99.6101%,which closely approaches the ideal value of 99.6094%.This algorithm not only guarantees image quality but also substantially raises the difficulty of decryption.

关键词： mersenne twister algorithm DNA coding confusion pixel XOR operation improved Joseph block scrambling

A Polarization Control Operator for Polarized Electromagnetic Wave Designing

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Chinese Journal of electronics 2024年第5期33卷 1253-1260页

作者： Shuo CUI Yaoyao LI Shijian ZHANG Ling CHEN Cheng CAO Donglin SU School of electronic and information Engineering Beihang University Shenyuan Honors college Beihang University Research Institute for Frontier science Beihang University

To describe and control the polarization state of electromagnetic waves, a polarization control operator of the complex vector form is proposed. Distinct from traditional descriptors, the proposed operator employs an angle parameter to configure the polarization state of the polarized wave. By setting the parameter in the proposed operator,the amplitude of the field components can be modified, resulting in changes in the magnitude and direction of the field vector, and thus realizing control of the polarization state of the electromagnetic wave. The physical meaning,orthogonal decomposition, and discrete property of the proposed operator are demonstrated through mathematical derivation. In the simulation examples, the polarization control operator with fixed and time-varying parameters is applied to the circularly polarized wave. The propagation waveform, the trajectory projection and the waveform cross section in different reception directions of the new electromagnetic waves are observed. The simulation results indicate that complex electromagnetic waves with more flexible polarization states can be obtained with the aid of the polarization operator.

关键词： Polarization Simulation Modulation Electromagnetic compatibility Vectors Trajectory Electromagnetics Electromagnetic wave Polarization control operator Polarization descriptor Polarization state MIMO

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Quantum circuit-based proxy blind signatures:A novel approach and experimental evaluation on the IBM quantum cloud platform

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Chinese physics B 2024年第5期33卷 247-253页

作者：娄小平昝慧茹徐雪娇 college of information {2. and Engineering Hunan Normal UniversityChangsha 410081China

This paper presents a novel approach to proxy blind signatures in the realm of quantum circuits,aiming to enhance security while safeguarding sensitive *** main objective of this research is to introduce a quantum proxy blind signature(QPBS)protocol that utilizes quantum logical gates and quantum measurement *** QPBS protocol is constructed by the initial phase,proximal blinding message phase,remote authorization and signature phase,remote validation,and de-blinding *** innovative design ensures a secure mechanism for signing documents without revealing the content to the proxy signer,providing practical security authentication in a quantum environment under the assumption that the CNOT gates are securely *** existing approaches,our proposed QPBS protocol eliminates the need for quantum entanglement preparation,thus simplifying the implementation *** assess the effectiveness and robustness of the QPBS protocol,we conduct comprehensive simulation studies in both ideal and noisy quantum environments on the IBM quantum cloud *** results demonstrate the superior performance of the QPBS algorithm,highlighting its resilience against repudiation and forgeability,which are key security concerns in the realm of proxy blind ***,we have established authentic security thresholds(82.102.)in the presence of real noise,thereby emphasizing the practicality of our proposed solution.

关键词： proxy blind signature quantum circuits quantum computation IBM quantum cloud platform

Lowering Sodium-Storage Lattice Strains of Layered Oxide Cathodes by Pushing Charge Transfer on Anions

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Energy & Environmental Materials 2024年第4期7卷 99-106页

作者： Na Li Wen Yin Baotian Wang Fangwei Wang Xiaoling Xiao Jinkui Zhao Enyue Zhao Songshan Lake Materials Laboratory Beijing National Laboratory for Condensed Matter physics Institute of Physics Chinese Academy of Sciences Spallation Neutron Source science Center Institute of High Energy physics Chinese Academy of Sciences college of Materials science and Opto-{2. Technology Center of Materials Science and Optoelectronics Engineering University of Chinese Academy of Sciences

Due to a high energy density,layered transition-metal oxides have gained much attention as the promising sodium-ion batteries ***,they readily suffer from multiple phase transitions during the Na extraction process,re... 详细信息

关键词： anionic redox reaction lattice strains layered oxide cathodes phase transitions sodium-ion battery