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Anisotropic spin transport and photoresponse characteristics detected by tip movement in magnetic single-molecule junction

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Chinese Physics B 2024年第4期33卷 640-648页

作者：陈登辉羊志付新宇秦申奥严岩王传奎李宗良邱帅 shandong key laboratory of Medical Physics and Image Processing&shandong provincial engineering and Technical Center of Light Manipulations School of Physics and ElectronicsShandong Normal UniversityJinan 250358China

Orientation-dependent transport properties induced by anisotropic molecules are enticing in single-molecule ***,using the first-principles method,we theoretically investigate spin transport properties and photoresponse characteristics in trimesic acid magnetic single-molecule junctions with different molecular adsorption orientations and electrode contact *** transport calculations indicate that a single-molecule switch and a significant enhancement of spin transport and photoresponse can be achieved when the molecular adsorption orientation changes from planar geometry to upright *** maximum spin polarization of current and photocurrent in upright molecular junctions exceeds 90%.Moreover,as the Ni tip electrode moves,the tunneling magnetoresistance of upright molecular junctions can be increased to 70%.The analysis of the spin-dependent PDOS elucidates that the spinterfaces between organic molecule and ferromagnetic electrodes are modulated by molecular adsorption orientation,where the molecule in upright molecular junctions yields higher spin *** theoretical work paves the way for designing spintronic devices and optoelectronic devices with anisotropic functionality base on anisotropic molecules.

关键词： molecular spintronics spin polarization tunneling magnetoresistance photocurrent single-molecule junctions

The governance technology for blockchain systems:a survey

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Frontiers of Computer Science 2024年第2期18卷 181-197页

作者： Guocheng ZHU Debiao HE Haoyang AN Min LUO Cong PENG School of Cyber Science and engineering Wuhan UniversityWuhan 430072China shandong provincial key laboratory of Computer Networks Qilu University of Technology(Shandong Academy of Sciences)Jinan 250014China

After the Ethereum DAO attack in 2016,which resulted in significant economic losses,blockchain governance has become a prominent research ***,there is a lack of comprehensive and systematic literature review on blockchain *** deeply understand the process of blockchain governance and provide guidance for the future design of the blockchain governance model,we provide an in-depth review of blockchain *** this paper,first we introduce the consensus algorithms currently used in blockchain and relate them to governance ***,we present the main content of off-chain governance and investigate two well-known off-chain governance ***,we investigate four common on-chain governance voting techniques,then summarize the seven attributes that the on-chain governance voting process should meet,and finally analyze four well-known on-chain governance blockchain projects based on the previous *** hope this survey will provide an in-depth insight into the potential development direction of blockchain governance and device future research agenda.

关键词： blockchain governance off-chain governance on-chain governance voting

Tuning Li/Ni mixing by reactive coating to boost the stability of cobalt-free Ni-rich cathode

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Journal of Energy Chemistry 2024年第10期97卷 20-29页

作者： Fanghui Du Xitong Zhang Yingchao Wang Lei Ding Pengfang Zhang Lingyang Liu Dong Wang Jianzong Man Yuling Chen Yunwu Li shandong provincial key laboratory of Chemical Energy Storage and Novel Cell Technology and School of Chemistry and Chemical Engineering Liaocheng University School of Materials Science and engineering Yancheng Institute of Technology

Cobalt-free cathode materials are attractive for their high capacity and low cost,yet they still encounter issues with structural and surface ***4,in particular,has garnered attention as an effective stabilizer for bulk and ***,the impact of interfacial reactions and elemental interdiffusion between AlPO4and LiNi0.95Mn0.05O2upon sintering on the bulk and surface remains *** this study,we demonstrate that during the heat treatment process,AlPO4decomposes,resulting in Al doping into the bulk of the cathode through elemental ***,PO43-reacts with the surface Li of material to form a Li3PO4coating,inducing lithium deficiency,thereby increasing Li/Ni *** suitable Li/Ni mixing,previously overlooked in AlPO4modification,plays a pivotal role in stabilizing the bulk and surface,exceeding the synergy of Al doping and *** presence of Ni2+ions in the lithium layers contributes to the stabilization of the delithiated structure via a structural pillar ***,suitable Li/Ni mixing can stabilize the lattice oxygen and electrode-electrolyte interface by increasing oxygen removal energy and reducing the overlap between the Ni3+/4+egand O2-2p *** findings offer new perspectives for the design of stable cobalt-free cathode materials.

关键词： Al doping Cobalt-free Ni-rich cathode Li/Ni mixing Li3PO4 coating Lithium-ion batteries

Impact of Annealing on the Melt Recrystallization of a-PDLA/α-PLLA Double-layered Films

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Chinese Journal of Polymer Science 2024年第2期42卷 230-238,I0009页

作者： Yun-Peng Li Hao-Ran Shen Shao-Juan Wang Hao Zhang Jian Hu Rui Xin Xiao-Li Sun Shou-Ke Yan key laboratory of Rubber-Plastics Ministry of Education/Shandong Provincial Key Laboratory of Rubber-plasticsQingdao University of Science&TechnologyQingdao266042China State key laboratory of Chemical Resource engineering Beijing University of Chemical TechnologyBeijing100029China

Poly(lactic acid)(PLA) as a bio-based polymer with biodegradability and biocompatibility has attracted much attention. To manipulate its properties for different applications, regulation of crystal structure and crystalline morphology becomes an attractive research topic. In this work, the structure evolution of layered samples containing an amorphous poly(D-lactide)(PDLA) layer and a crystalline poly(L-lactide)(PLLA)layer with highly oriented edge-on α lamellar crystals after annealing at 150 ℃ or/and after melt-recrystallization has been studied by AFM, FTIR,and TEM combined with electron diffraction. The results demonstrate that melt recrystallization of the as-prepared sample leads to the formation of abundant randomly oriented PLA stereo-complex(PLA SC) crystals. Annealing at 150 ℃ results in the formation of a small amount of oriented PLA SC crystals at the interface. These PLA SC crystals show great impact on the recrystallization behavior of sample after melting at 190 ℃ and then crystallizing at 90 ℃. First, they impede the mutual diffusion of the overlying PDLA and underlying PLLA, and thus reduce their stereocomplexation ability as manifested by the decreased amount of PLA SC crystals. Second, they act as substrate to initiate the epitaxial crystallization of the overlying PDLA and underlying PLLA, which ensures the production of a highly oriented structure of PDLA and PLLA after melt recrystallization again.

关键词： Poly(L-lactide) Poly(D-lactide) Double layer Stereocomplex

Numerical and experimental study on the falling film flow characteristics with the effect of co-current gas flow in hydrogen liquefaction process

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Petroleum Science 2024年第2期21卷 1369-1384页

作者： Chong-Zheng Sun Yu-Xing Li Hui Han Xiao-Yi Geng Xiao Lu College of Energy Storage Technology Shandong University of Science and TechnologyQingdao 266590ShandongChina College of Pipeline and Civil engineering/shandong provincial key laboratory of Oil&Gas Storage and Transportation Safety China University of PetroleumQingdao 266580ShandongChina

Liquid hydrogen storage and transportation is an effective method for large-scale transportation and utilization of hydrogen energy. Revealing the flow mechanism of cryogenic working fluid is the key to optimize heat exchanger structure and hydrogen liquefaction process(LH2). The methods of cryogenic visualization experiment, theoretical analysis and numerical simulation are conducted to study the falling film flow characteristics with the effect of co-current gas flow in LH2spiral wound heat *** results show that the flow rate of mixed refrigerant has a great influence on liquid film spreading process, falling film flow pattern and heat transfer performance. The liquid film of LH2mixed refrigerant with column flow pattern can not uniformly and completely cover the tube wall surface. As liquid flow rate increases, the falling film flow pattern evolves into sheet-column flow and sheet flow, and liquid film completely covers the surface of tube wall. With the increase of shear effect of gas-phase mixed refrigerant in the same direction, the liquid film gradually becomes unstable, and the flow pattern eventually evolves into a mist flow.

关键词： Hydrogen liquefaction Spiral wound heat exchanger Flow pattern transition Falling film flow

14.1 W continuous-wave dual-end diode-pumped Er:Lu_(2)O_(3)laser at 2.85μm

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Chinese Optics Letters 2024年第1期22卷 84-89页

作者：梁洋洋李涛张百涛何京良 Sascha Kalusniak 赵显 Christian Kränkel key laboratory of Laser&Infrared System Ministry of EducationShandong UniversityQingdao 266237China School of Information Science and engineering Shandong Provincial Key Laboratory of Laser Technology and ApplicationShandong UniversityQingdao 266237China Institute of Novel Semiconductors State Key Laboratory of Crystal MaterialsShandong UniversityJinan 250100China Leibniz-Institut für Kristallzüchtung(IKZ) Berlin 12489Germany

We present our efforts towards power scaling of Er:Lu_(2)O_(3)lasers at 2.85μ*** applying a dual-end diode-pumped resonator scheme,we achieve an output power of 14.1 W at an absorbed pump power of 59.7 W with a slope efficiency of 26%.In a single-end pumped resonator scheme,an output power of 10.1 W is reached under 41.9 W of absorbed pump *** the best of our knowledge,this is the first single crystalline mid-infrared rare-earth-based solid-state laser with an output power exceeding 10 W at room temperature.

关键词： high-power continuous-wave laser mid-infrared laser dual-end pump scheme

Coherence entropy during propagation through complex media

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Advanced Photonics 2024年第4期6卷 25-35页

作者： Xingyuan Lu Zhuoyi Wang Qiwen Zhan Yangjian Cai Chengliang Zhao Soochow University School of Physical Science and Technology Jiangsu Key Laboratory of Frontier Material Physics and Devices University of Shanghai for Science and Technology School of Optical-Electrical and Computer Engineering shandong Normal University School of Physics and Electronics Shandong Provincial Engineering and Technical Center of Light ManipulationsShandong Provincial Key Laboratory of Optics and Photonic Device East China Normal University Joint Research Center of Light Manipulation Science and Photonic Integrated Chip of East China Normal University and Shandong Normal University

The deformation, flicker, and drift of a light field owing to complex media such as a turbulent atmosphere have limited its practical applications. Thus, research on invariants in randomly fluctuated light fields has garnered considerable attention in recent years. Coherence is a statistical property of light,while its full and quantitative characterization is challenging. Herein, we successfully realize the orthogonal modal decomposition of partially coherent beams and introduce the application of coherence entropy as a global coherence characteristic of such randomly fluctuated light fields. It is demonstrated that coherence entropy remains consistent during propagation in a unitary system by unraveling complex channels. As representative examples, we study the robustness of coherence entropy for partially coherent beams as they propagate through deformed optical systems and turbulent media. Coherence entropy is anticipated to serve as a key metric for evaluating the propagation of partially coherent beams in complex channels. This study paves the way for a broader application scope of a customized low-coherence light field through nonideal optical systems and complex media.

关键词： Global system for mobile communications Atmospheric propagation Modal decomposition Matrices Turbulence Physical coherence Deformation Partial coherence Spherical lenses Optical coherence

Study on Catalytic Behavior of Iron-based Catalyst with IITP as Electron Donor in the Polymerization of Butadiene

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Chinese Journal of Polymer Science 2024年第5期42卷 612-619,I0007页

作者： Shi-Liang Xu Ying-Nan Zhao Yao Yu Qi Yang Li-Hua Na Heng Liu Chun-Yu Zhang Xue-Quan Zhang key laboratory of Advanced Rubber Material Ministry of EducationSchool of Polymer Science and EngineeringQingdao University of Science&TechnologyQingdao266042China shandong provincial College laboratory of Rubber Material and engineering School of Polymer Science and EngineeringQingdao University of Science&TechnologyQingdao266042China key Lab of Rubber-Plastics Ministry of Education/Shandong Provincial Key Lab of Rubber-plasticsSchool of Polymer Science and EngineeringQingdao University of Science&TechnologyQingdao266042China

In this study,a novel iron-based catalyst system,Fe(acac)3/(isocyanoimino)triptenylphosphorane(IITP)/AlR3,was employed for the synthesis of syndiotactic 1,2-polybutadiene in *** catalyst system exhibits remarkably high catalytic activity,achieving a polymerization activity of 762 kgpolymer·molcatalyst^(-1)·h^(-1)at 50℃with a[BD]/[Fe]molar ratio of ***,living polymerization characteristic were observed during the investigation of the polymerization kinetics of 1,3-butadiene *** characteristics were well demonstrated by a narrow molecular weight distribution(PDI≈2.0)of the resulting polybutadiene and a linear relationship between-ln(1-c)and polymerization time as well as number average molecular weight and polymer *** resultant polymer showed a 1,2-selectivity of approximately 76%and stereoregularity ranging from 62%to 73%(rrrr).Additionally,through kinetic studies on polymerization reaction,an apparent activation energy Ea value of this catalytic system was calculated to be 84.98 kJ·mol^(-1),which suggests that high polymerization temperature favors efficient polymerization.

关键词： Iron catalyst Syndiotactic 1,2-polybutadiene Elastomers Donor Selectivity

Fabrication of Superhydrophobic–Hydrophilic Patterned Cu@Ag Composite SERS Substrate via Femtosecond Laser

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Nanomanufacturing and Metrology 2024年第1期7卷 1-14页

作者： Yuheng Zhang Zongwei Xu Kun Zhang Ying Song Bing Dong Jianshi Wang Mengzhi Yan Qingqing Sun State key laboratory of Precision Measuring Technology and Instruments Laboratory of Micro/Nano Manufacturing TechnologyTianjin UniversityTianjin 300072China shandong Agricultural Equipment Intelligent engineering laboratory Shandong Provincial Key Laboratory of Horticultural Machinery and EquipmentCollege of Mechanical and Electronic EngineeringShandong Agricultural UniversityTai’an 827101China

Ultralow concentration molecular detection is critical in various fields,e.g.,food safety,environmental monitoring,and dis-ease *** sensitive surface-enhanced Raman scattering(SERS)based on ultra-wettable surfaces has attracted attention due to its unique ability to detect trace ***,the complexity and cost associated with the preparation of traditional SERS substrates restrict their practical ***,an efficient SERS substrate preparation with high sensitivity,a simplified process,and controllable cost is *** this study,a superhydrophobic–hydrophilic patterned Cu@Ag composite SERS substrate was fabricated using femtosecond laser processing technology combined with silver plating and surface modification *** inducing periodic stripe structures through femtosecond laser processing,the developed substrate achieves uniform distribution *** the surface wettability difference,the object to be measured can be confined in the hydrophilic region and the edge of the hydrophilic region,where the analyte is enriched by the coffee ring effect,can be quickly located by surface morphology difference of micro-nanostructures;thus,greatly improving detec-tion *** fabricated SERS substrate can detect Rhodamine 6G(R6G)at an extraordinarily low concentration of 10^(−15)mol/L,corresponding to an enhancement factor of 1.53×10^(8).This substrate has an ultralow detection limit,incurs low processing costs and is simple to prepare;thus,the substrate has significant application potential in the trace analysis field.

关键词： Femtosecond laser Surface-enhanced Raman scattering Coffee ring effect Superhydrophobic–hydrophilic surface