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CES Transactions on Electrical Machines and Systems 2024年第2期8卷 127-142页

作者： bo Pang Qi si Pan Jiang Kai Liao Xiaojuan Zhu Jianwei Yang Zhengyou He the College of Electrical Engineering Southwest Jiaotong UniversityChengdu 610031China IEEE

High-frequency oscillation(HFO)of gridconnected wind power generation systems(WPGS)is one of the most critical issues in recent years that threaten the safe access of WPGS to the *** the WPGS can damp HFO is becoming more and more vital for the development of wind *** HFO phenomenon of wind turbines under different scenarios usually has different ***,engineers need to acquire the working mechanisms of the different HFO damping technologies and select the appropriate one to ensure the effective implementation of oscillation damping in practical *** paper introduces the general assumptions of WPGS when analyzing HFO,systematically summarizes the reasons for the occurrence of HFO in different scenarios,deeply analyses the key points and difficulties of HFO damping under different scenarios,and then compares the technical performances of various types of HFO suppression methods to provide adequate references for engineers in the application of ***,this paper discusses possible future research difficulties in the problem of HFO,as well as the possible future trends in the demand for HFO damping.

关键词： Damping method High-frequency oscillation Stability Wind power generation

BL03HB: a Laue microdiffraction beamline for both protein crystallography and materials science at SSRF

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Nuclear Science and Techniques 2024年第7期35卷 68-78页

作者： Zhi-Jun Wang si-Sheng Wang Zheng-Huang Su Li Yu Yu-Zhu Wang bo Sun Wen Wen Xing-Yu Gao Shanghai Advanced Research Institute Chinese Academy of SciencesShanghai201210China University of Chinese Academy of Science Beijing100049China

A Laue microdiffraction beamline(BL03HB) was constructed at the Shanghai Synchrotron Radiation Facility(SSRF).This beamline features two consecutive focusing points in two different sectors within its end station, the first dedicated to protein crystallography and the other tailored to materials science applications. Based on a superbend dipole magnet with a magnetic field of 2.29 T, a two-stage focusing design was implemented with two sets of Kirkpatrick-Baez mirrors to achieve a micro white beam as small as 4.2 μ m ×4.3 μ m at the first sector and 0.9 μ m ×1.3 μ m at the second sector in the standard beamline operation mode at SSRF. The X-ray microbeam in the two sectors can be easily switched between monochromatic and white beams by moving a four-bounce monochromator in or out of the light path, respectively. In the protein crystallography sector, white-beam Laue microdiffraction was demonstrated to successfully determine the structure of protein crystals from only a few images of diffraction data collected by a Pilatus 2 M area detector. In the materials science sector,the white-beam Laue diffraction was collected in a reflection geometry using another Pilatus 2 M area detector, which could map the microstructural distribution on the sample surface by scanning the samples. In general, the BL03HB beamline promotes the application of Laue microdiffraction in both protein crystallography and materials science. This paper presents a comprehensive overview of the BL03HB beamline, end station, and the first commission results.

关键词： Crystallography White-beam Laue microdiffraction Beamline Synchrotron

A Post-Quantum Cross-Domain Authentication Scheme Based on Multi-Chain Architecture

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Computers, Materials & Continua 2024年第2期78卷 2813-2827页

作者： Yi-bo Cao Xiu-bo Chen Yun-Feng He Lu-Xi Liu Yin-Mei Che Xiao Wang Ke Xiao Gang Xu si-Yi Chen Information Security Center State Key Laboratory ofNetworking and Switching TechnologyBeijing University of Posts and TelecommunicationsBeijing100876China Information Center of China North Industries Group Corporation Beijing100089China School of Information Science and Technology North China University of TechnologyBeijing100144China

Due to the rapid advancements in network technology,blockchain is being employed for distributed data *** the Internet of Things(IoT)scenario,different participants manage multiple blockchains located in different trust domains,which has resulted in the extensive development of cross-domain authentication ***,the emergence of many attackers equipped with quantum computers has the potential to launch quantum computing attacks against cross-domain authentication schemes based on traditional cryptography,posing a significant security *** response to the aforementioned challenges,our paper demonstrates a post-quantum cross-domain identity authentication scheme to negotiate the session key used in the cross-chain asset exchange ***,our paper designs the hiding and recovery process of user identity index based on lattice cryptography and introduces the identity-based signature from lattice to construct a post-quantum cross-domain authentication ***,our paper utilizes the hashed time-locked contract to achieves the cross-chain asset exchange of blockchain nodes in different trust ***,the security analysis reduces the security of the identity index and signature to Learning With Errors(LWE)and Short Integer Solution(siS)assumption,respectively,indicating that our scheme has post-quantum *** but not least,through comparison analysis,we display that our scheme is efficient compared with the cross-domain authentication scheme based on traditional cryptography.

关键词： Cross-domain identity authentication lattice-based cryptography blockchain hashed time-locked contract

Strong Antiferromagnetic Exchange-Coupling Observed in Hydride-Bridged Dimeric Dysprosium(Ⅲ)single-Molecule Magnet

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Chinese Journal of Chemistry 2024年第4期42卷 391-396页

作者： Qian-Cheng Luo Ke-Xin Yu peng-bo Jin Ye-Ye Liu Yuan-Qi Zhai Yan-Zhen Zheng Frontier Institute of Science and Technology State Key Laboratory of Electrical Insulation and Power EquipmentXi'an Key Laboratory of Electronic Devices and Materials ChemistrySchool of Chemistry and School of PhysicsXi'an Jiaotong University99 Yanxiang RoadXi'anShaanxi710054 China

One dihydride-bridged dimeric Dy(Ⅲ)guanidinate complex,formulated as[{(Me_(3)si)_(2)NC(NiPr)_(2)}_(2)Dy(μ-H)]_(2)(1Dy),was successfully isolated and the introduction of hydride bridges significantly reduces the intramolecular Dy(Ⅲ)…Dy(Ⅲ)distance to only 3.688(1)Å.To investigate the effect of such a short Dy(Ⅲ)…Dy(Ⅲ)distance on magnetism,we also prepared its dibromide-bridged analogue[{(Me_(3)si)_(2)NC(NiPr)_(2)}_(2)Dy(μ-Br)]_(2)(2Dy),which has a much longer Dy(Ⅲ)…Dy(Ⅲ)distance of 4.605(4)Å.Surprisingly,2Dy demonstrates much larger effective energy barrier for magnetization reversal(U_(eff))and higher blocking temperature(T_(B)).The worse performance of 1Dy is attributed to the concerted effect of strong antiferromagnetic interactions between Dy(Ⅲ)ions(J_(total)=–2.683 cm^(–1))and the unparallel arrangement of magnetic principle axes of the Dy(Ⅲ)ions for 1Dy.

关键词： single-molecule magnets Lanthanides Guanidinate ligand Hydride bridge Magnetic properties Ab initio calculations

Giant reversible barocaloric effects with high thermal cycle stability in epoxybonded(MnCoGe)_(0.96)(CuCoSn)_(0.04) composite

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International Journal of Minerals,Metallurgy and Materials 2024年第11期31卷 2528-2534页

作者： Yafei Kuang Kun Tao bo Yang peng Tong Yan Zhang Zhigang Sun Kewei Zhang Dunhui Wang Jifan Hu Liang Zuo College of Materials Science and Engineering Taiyuan University of Science and TechnologyTaiyuan 030024China Shanxi Key Laboratory of Magnetic and Electric Functional Materials and Applications Taiyuan University of Science and TechnologyTaiyuan 030024China Key Laboratory of Materials Physics Institute of Solid State PhysicsChinese Academy of SciencesHefei 230031China Key Laboratory for Anisotropy and Texture of Materials(Ministry of Education) School of Materials Science and EngineeringNortheastern UniversityShenyang 110819China School of Electronics and Information Hangzhou Dianzi UniversityHangzhou 310018China

Hexagonal MnMX-based(M=Co or Ni,X=si or Ge)alloys exhibit giant reversible barocaloric ***,giant volume expansion would result in the as-cast MnMX ingots fragmenting into powders,and inevitably bring the deterioration of mechanical properties and *** fragmentation can bring degradation of structural transformation entropy change during cyclic application and removal of *** this paper,giant reversible barocaloric effects with high thermal cycle stability can be achieved in the epoxy bonded(MnCoGe)0.96(CuCoSn)0.04 *** reversible isothermal entropy change of 43.0 J·kg^(−1)·K^(−1) and adiabatic temperature change from barocaloric effects(ΔT_(BCE))of 15.6 K can be obtained within a wide temperature span of 30 K at 360 MPa,which is mainly attributed to the integration of the change in the transition temperature driven by pressure of−101 K·GPa^(−1) and suitable thermal hysteresis of 11.1 ***,the variation of reversibleΔ_(TBCE) against the applied hydrostatic pressure reaches up to 43 K·GPa^(−1),which is at the highest level among the other reported giant barocaloric *** importantly,after 60 thermal cycles,the composite does not break and the calorimetric curves coincide well,demonstrating good thermal cycle stability.

关键词： barocaloric effects cycle stability reversible isothermal entropy change reversible adiabatic temperature change MnCoGe alloys

Arbitrary topological charge vortex beams from carbon dots random lasers

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Rare Metals 2024年第8期43卷 3844-3853页

作者： Xiang-Dong Wang Xiao-bo Mi Jiu-Ru He Feng-Ying Ma Jun-Qiao Wang Li Song Yong-Qiang Zhang si-Yu Lu Yong-Sheng Hu School of Physics and Microelectronics Zhengzhou UniversityZhengzhou 450001China State Key Laboratory of Reliability and Intelligence of Electrical Equipment and Tianjin Key Laboratory of Electronic Materials and Devices School of Electronics and Information EngineeringHebei University of TechnologyTianjin 300401China Green Catalysis Center College of ChemistryZhengzhou UniversityZhengzhou450001China

Vortex beams have attracted great attention due to their promising applications in the fields of high-capacity optical communication,optical micromanipulation,and quantum information ***,we demonstrate vortex beams with flexible control of the topological charge and modes in a carbon dots random laser for the first *** beams with different types,including the Laguerre-Gaussian(LG),Bessel-Gaussian(BG),LG-superposition,and polarized vortex beams with topological charges up to 50,have been successfully ***,vortex beams can be well realized in carbon dots random lasers with different emission wavelengths covering from 465 to 612 *** work would not only enrich the types of vortex laser,especially for solution-processable lasers,but also provide a new route to realizing multicolor and wavelength-tunable vortex lasers.

关键词： Carbon dots Random lasers Vortex beam Topological charge Spatial light modulator

Measurement of the high energyγ-rays from heavy ion reactions usingČerenkov detector

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Nuclear Science and Techniques 2024年第2期35卷 123-130页

作者： Da-Wei si Yan Zhou Sheng Xiao Zhi Qin Dong Guo Yu-Hao Qin Yi-Jie Wang bo-Yuan Zhang Bai-Ting Tian Zhi-Gang Xiao Department of Physics Tsinghua UniversityBeijing 100084China

The energetic bremsstrahlung photons up to 100 MeV produced in heavy ion collisions can be used as a sensitive probe for short-range correlation in atomic nuclei. The energy of the γ-rays can be measured by collecting the Čerenkov light in the medium induced by the fast electrons generated in the Compton scattering or electromagnetic shower of the incident γray. Two types of detectors based on pure water and lead glass as sensitive materials were designed for this purpose. The γresponse and optical photon propagation in the detectors were simulated based on electromagnetic and optical processes in Geant4. The inherent energy resolutions of 0.022(4) + 0.51(2)∕E^(1/2)_(γ) for water and 0.0026(3) + 0.446(3)∕E^(1/2)_(γ) for lead glass were obtained. The geometry sizes of the lead glass and water were optimized to 30 cm × 30 cm × 30 cm and 60 cm × 60 cm ×120 cm, respectively, to detect high-energy γ-rays at 160 MeV. The Hough transform method was applied to reconstruct the direction of the incident γ-rays, providing the ability to experimentally distinguish the high-energy γ-rays produced in the reactions on the target from random background cosmic-ray muons.

关键词： Bremsstrahlungγ-rays Čerenkov Geant4 Energy resolution Direction reconstruction Hough transform

Microfluidic preparation of surfactant-free ultrafine DAAF with tunable particle size for insensitive initiator explosives

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DEFENCE TECHNOLOGY 2024年第9期39卷 42-52页

作者： Yang, bo Li, Rui Cao, Wei He, si-min Zhu, Jincan Wu, Qi Ding, Heng Chen, Jin Wang, Weimiao Qiao, Zhiqiang Li, Xiaodong Yang, Guangcheng China Acad Engn Phys Inst Chem Mat Mianyang 621900 Peoples R China Nanjing Univ Sci & Technol Sch Chem Engn Nanjing 210094 Peoples R China Southwest Univ Sci & Technol Mianyang 621010 Peoples R China

High purity and ultrafine DAAF (u-DAAF) is an emerging insensitive charge in initiators. Although there are many ways to obtain u-DAAF, developing a preparation method with stable operation, accurate control, good quality consistency, equipment miniaturization, and minimum manpower is an inevitable requirement to adapt to the current social technology development trend. Here reported is the microfluidic preparation of u-DAAF with tunable particle size by a passive swirling microreactor. Under the guidance of recrystallization growth kinetics and mixing behavior of fluids in the swirling microreactor, the key parameters (liquid flow rate, explosive concentration and crystallization temperature) were screened and optimized through screening experiments. Under the condition that no surfactant is added and only experimental parameters are controlled, the particle size of recrystallized DAAF can be adjusted from 98 nm to 785 nm, and the corresponding specific surface area is 8.45 m(2)g(-1) to 1.33 m(2)g(-1). In addition, the preparation method has good batch stability, high yield (90.8%-92.6%) and high purity (99.0%-99.4%), indicating a high practical application potential. Electric explosion derived flyer initiation tests demonstrate that the u-DAAF shows an initiation sensitivity much lower than that of the raw DAAF, and comparable to that of the refined DAAF by conventional spraying crystallization method. This study provides an efficient method to fabricate u-DAAF with narrow particle size distribution and high reproducibility as well as a theoretical reference for fabrication of other ultrafine explosives. (c) 2024 China Ordnance Society. Publishing services by Elsevier B.V. on behalf of KeAi Communications Co. Ltd. This is an open access article under the CC BY-NC-ND license (http://***/ licenses/by-nc-nd/4.0/).

关键词： Microfluidic preparation Screening crystallization conditions Narrow particle size distribution Low initiation sensitivity Ultrafine DAAF ASsiSTED PRECIPITATION ENERGETIC MATERIALS SOL-GEL siMULATION PLATFORM CL-20 HNS

Efficacy and safety of endoscopic submucosal dissection for early gastric cancer and precancerous lesions in elderly patients

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World Journal of Gastrointestinal Surgery 2024年第2期16卷 511-517页

作者： Wen-si Xu Hui-Yu Zhang Shuang Jin Qi Zhang Hong-Dan Liu Ming-Tao Wang bo Zhang Department of Gastroenterology The Third Affiliated Hospital of Qiqihar Medical UniversityQiqihar 161099Heilongjiang ProvinceChina

BACKGROUND With advancements in the development of endoscopic technologies,the endo-scopic submucosal dissection(ESD)has been one of the gold-standard therapies for early gastric *** To investigate the efficacy and safety ESD in the treatment of early gastric cancer and precancerous lesions in the elderly *** Seventy-eight elderly patients with early gastric cancer and precancerous lesions admitted to the Third Affiliated Hospital of Qiqihar Medical University were se-lected and classified into two groups according to the different surgical therapies they received between January 2021 and June *** them,39 patients treated with ESD were included in an experimental group,and 39 patients treated with endoscopic mucosal resection(EMR)were included in a control *** compared the basic intraoperative conditions,postoperative short-term recovery,long-term recovery effects and functional status of gastric mucosa between the two groups;the basic intraoperative conditions included lesion resection,intra-operative bleeding and operation time;the postoperative short-term recovery assessment indexes were length of hospital stay and incidence of surgical complic-ations;and the long-term recovery assessment indexes were the recurrence rate at 1 year postoperatively and the survival situation at 1 year and 3 years postoper-atively;and we compared the preoperative and predischarge serum pepsinogen I(PG I)and PG II levels and PG I/PG II ratio in the two groups before surgery and *** The curative resection rate and the rate of en bloc resection were higher in the experimental group than in the control *** intraoperative bleeding volume was higher in the experimental group than in the control *** operation time was longer in the experimental group than that in the control group,and the rate for base residual focus was lower in the experimental group than that of the control group,and the differences were all statistically signifi

关键词： Endoscopic submucosal dissection Endoscopic mucosal resection Early gastric cancer Serum pepsinogen Elderly

A peak enhancement of frequency response of waveguide integrated silicon-based germanium avalanche photodetector

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Journal of Semiconductors 2024年第7期45卷 61-68页

作者： Linkai Yi Daoqun Liu Wenzheng Cheng Daimo Li Guoqi Zhou peng Zhang bo Tang Bin Li Wenwu Wang Yan Yang Zhihua Li Institute of Microelectronics Chinese Academy of SciencesBeijing 100029China School of Electronic Electrical and Communication Engineering University of Chinese Academy of SciencesBeijing 100049China

Avalanche photodetectors(APDs) featuring an avalanche multiplication region are vital for reaching high sensitivity and responsivity in optical transceivers. Waveguide-coupled Ge-on-si separate absorption, charge, and multiplication(SACM)APDs are popular due to their straightforward fabrication process, low optical propagation loss, and high detection sensitivity in optical communications. This paper introduces a lateral SACM Ge-on-si APD on a silicon-on-insulator(SOI) wafer, featuring a 10 μm-long, 0.5 μm-wide Ge layer at 1310 nm on a standard 8-inch silicon photonics platform. The dark current measures approximately 38.6 μA at-21 V, indicating a breakdown voltage greater than-21 V for the device. The APDs exhibit a unitgain responsivity of 0.5 A/W at-10 V. At-15 V, their responsivity reaches 2.98 and 2.91 A/W with input powers of-10 and-25 dBm, respectively. The device's 3-dB bandwidth is 15 GHz with an input power of-15 dBm and a gain is 11.68. Experimental results show a peak in impedance at high bias voltages, attributed to inductor and capacitor(LC) circuit resonance, enhancing frequency response. Furthermore, 20 Gbps eye diagrams at-21 V and-9 dBm input power reveal signal to noise ratio(SNRs) of 5.30. This lateral SACM APD, compatible with the stand complementary metal oxide semiconductor(CMOS) process,shows that utilizing the peaking effect at low optical power increases bandwidth.

关键词： photodetectors optical communications responsivity 3-dB bandwidth