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Atom-optically synthetic gauge fields for a noninteracting Bose gas

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Light(Science & Applications) 2022年第3期11卷 15-21页

作者： Yuqing Li Jiahui Zhang Yunfei Wang Huiying Du jizhou wu Wenliang Liu Feng Mei Jie Ma Liantuan Xiao Suotang Jia State Key Laboratory of Quantum Optics and Quantum Optics Devices Institute of Laser SpectroscopyShanxi UniversityTaiyuan030006China Collaborative Innovation Center of Extreme Optics Shanxi UniversityTaiyuanShanxi030006China

Synthetic gauge fields in synthetic dimensions are now of great *** concept provides a convenient manner for exploring topological phases of ***,we report on the first experimental realization of an atom-optically synthetic gauge field based on the synthetic momentum-state lattice of a Bose gas of ^(133)Cs atoms,where magnetically controlled Feshbach resonance is used to tune the interacting lattice into noninteracting ***,we engineer a noninteracting one-dimensional lattice into a two-leg ladder with tunable synthetic gauge *** observe the flux-dependent populations of atoms and measure the gauge field-induced chiral currents in the two *** also show that an inhomogeneous gauge field could control the atomic transport in the *** results lay the groundwork for using a clean noninteracting synthetic momentum-state lattice to study the gauge field-induced topological physics.

关键词： gauge interacting synthetic

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全自动挤奶机器人领域在华专利分析

农学学报 2024年第1期14卷 72-82页

作者：赵慧敏丁芳程国明吾际舟聂迎利中国农业科学院农业信息研究所北京100081 中国奶业协会北京100193 山东省东营市畜牧兽医站山东东营257091

深入研究全自动挤奶机器人在中国的专利布局,对中国的技术研发和保护有重要意义。基于德温特(DI)专利数据库,利用文献计量法和主题聚类法,从专利申请年度变化、技术来源国、专利权人、专利法律状态、专家分类、IPC分类、研究热点等方面... 详细信息

深入研究全自动挤奶机器人在中国的专利布局,对中国的技术研发和保护有重要意义。基于德温特(DI)专利数据库,利用文献计量法和主题聚类法,从专利申请年度变化、技术来源国、专利权人、专利法律状态、专家分类、IPC分类、研究热点等方面分析归纳出全自动挤奶机器人技术中国布局的特点。中国在该领域起步慢,2011年进入技术发展期。该技术重点专利权人集中,整体失效专利占比41%,专利维持力度不强。国外机构申请专利占比22.6%,主要来自瑞典、德国、荷兰和美国,专利权人主要包括利拉伐、基伊埃等。国内机构中授权且有效的专利数量较多的是安徽永牧、山东成城物联网等。国外机构在华专利有效专利比例和技术方向多于国内机构,尤其在自动奶杯套杯及脱落的定位及乳头识别装置、自动奶杯套杯或脱杯机械臂及动力装置、自动添加或移除奶牛群的挤奶机器或设备方向。建议中国机构建立专利池等有效合作机制,加强企业和大学、科研机构的合作,加强整体专利布局力度和前沿技术专利布局。

关键词：全自动挤奶机器人全自动挤奶系统专利专利布局技术分析

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巴西农业生产增长因素分析及对中国的启示

农业展望 2024年第6期20卷 52-58页

作者：赵慧敏吾际舟赵瑞雪孔令博聂迎利中国农业科学院农业信息研究所北京100081

巴西用了短短40年转型为农业强国,从粮食净进口国转变为世界领先的出口国之一。巴西农业产量的大幅增长被称为巴西绿色革命,被认为是20世纪下半叶最重要的世界发展之一。本研究通过调查研究总结巴西农业生产的发展要素,发现其主要包括... 详细信息

巴西用了短短40年转型为农业强国,从粮食净进口国转变为世界领先的出口国之一。巴西农业产量的大幅增长被称为巴西绿色革命,被认为是20世纪下半叶最重要的世界发展之一。本研究通过调查研究总结巴西农业生产的发展要素,发现其主要包括加强国际合作、调整国家政策与经济措施、紧抓国内外需求变化、设立科研机构、专注农业生物技术研发,借鉴巴西农业发展的经验和问题,对中国农业农村现代化发展提出以下建议:在做好规划和监管下推行生物技术的使用,在国际合作中促进技术发展并保护知识产权,在耕地面积拓展中做好环境保护。

关键词：巴西农业生产发展要素生物技术启示

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Topological quantum walks:Theory and experiments

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Frontiers of physics 2019年第6期14卷 3-8页

作者： jizhou wu Wei-Wei Zhang Barry C·Sanders Shanghai Branch National Laboratory for Physical Sciences at MicroscaleUniversity of Science and Technology of ChinaShanghai 201315China CAS Center for Excellence and Synergetic Innovation Center in Quantum Information and Quantum Physics University of Science and Technology of ChinaHefei 230026China Centre for Engineered Quantum Systems School of PhysicsThe University of SydneySydneyNew South Wales 2006Australia Institute for Quantum Science and Technology University of CalgaryCalgaryAB T2N 1N4Canada

Inspired by recent breakthroughs with topological quantum materials,which pave the way to novel,high-efficiency,low-energy magnetoelectric devices[1-3]and fault-tolerant quantum information processing[4],inter alia,topological quantum walks have emerged as an exciting topic in its own right,especially due to the theoretical and experimental simplifications this approach offers[5-14].Motivated by impressive progress in topological quantum walks,we provide a perspective on theoretical studies and experimental investigations of topological quantum walks focusing on current explorations of topological properties arising for single-walker quantum walks.

关键词： quantum topological walk

Wide and fast-frequency tuning for a stabilized diode laser

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Frontiers of physics 2022年第2期17卷 1-5页

作者： Yunfei Wang Yuqing Li jizhou wu Wenliang Liu Peng Li Yongming Fu Jie Ma Liantuan Xiao Suotang Jia State Key Laboratory of Quantum Optics and Quantum Optics Devices Institute of Laser SpectroscopyCollege of Physics and Electronics EngineeringShanxi UniversityTaiyuan 030006China Collaborative Innovation Center of Extreme Optics Shanxi UniversityTaiyuan 030006China College of Physics and Electronic Engineering Shanxi UniversityTaiyuan 030006China

External-cavity diode laser(ECDL)has important applications in many fundamental and applied *** we report a method to fast and widely tune the frequency of a stabilized *** beat frequency between the ECDL and a frequency-locked reference laser is identified by the voltagecontrolled oscillator contained in a phase detector,whose output voltage is subtracted from the flexibly controlled PC signal to generate an error signal for stabilizing the *** output frequency of the stabilized ECDL can be shifted at a short characteristic time of∼150µs within a range of∼620 *** wide and fast-frequency tuning achieved by our method is compared with other previous *** demonstrated the performance of our method by the efficient sub-Doppler cooling of Cs atoms with the temperature as low as 6µK.

关键词： external-cavity diode laser frequency stabilization laser cooling interaction of laser with atoms

Generation of coherent blue light via bichromatic pumping in cesium vapor

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Frontiers of physics 2023年第4期18卷 283-290页

作者： Guiyuan Ge Li Tian Guoqing Zhang Ningxuan Zheng Wenliang Liu Vladimir Sovkov jizhou wu Yuqing Li Yongming Fu Peng Li Jie Ma Liantuan Xiao Suotang Jia State Key Laboratory of Quantum Optics and Quantum Optics Devices Institute of Laser SpectroscopyShanxi UniversityTaiyuan 030006China Collaborative Innovation Center of Extreme Optics Shanxi UniversityTaiyuan 030006China St.Petersburg State University 7/9 Universitetskaya nab.St.Petersburg 199034Russia College of Physics and Electronic Engineering Shanxi UniversityTaiyuan 030006China Hefei National Laboratory Hefei 230088China

Diode-pumped alkali lasers,possessing high efficiency and narrow linewidth,can provide feasible solutions for wavelength ranges difficult to reach by commercial *** this study,we investigate a generation of coherent blue light(CBL)via four-wave mixing(FWM)-based up-conversion processes in cesium(Cs)vapor.A bichromatic pumping scheme with 852-and 917-nm lasers drives the Cs atoms to the 6D5/2 excited level,followed by cascaded decay of 6D5/2→7 P3/2→6 S1/2,producing 456-nm CBL under phase matching *** fluorescence in multiple bands from blue to near-and far-infrared in the FWM process is demonstrated under different experimental *** optimize the experimental parameters,we investigate the dependence of 456-nm CBL on the vapor temperature,frequency,and intensity of the two pump lasers.A maximum power of 2.94 mW is achieved with pump powers of 430 mW(for 852 nm)and 470 mW(for 917 nm).The corresponding conversion efficiency is 1.5%/W,three-fold higher than those in previous *** results can contribute to fundamental research on atom–photon interactions and quantum metrology.

关键词： four wave mixing conversion coherent blue beam bichromatic pumping

Spin current in a spinor Bose–Einstein condensate induced by a gradient magnetic field

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Chinese Physics B 2022年第11期31卷 207-210页

作者：田丽郑宁宣蹇君刘文良武寄洲李玉清付永明李鹏 Vladimir Sovkov 马杰肖连团贾锁堂 State Key Laboratory of Quantum Optics and Quantum Optics Devices Institute of Laser SpectroscopyShanxi UniversityTaiyuan 030006China Collaborative Innovation Center of Extreme Optics Shanxi UniversityTaiyuan 030006China School of Science Key Laboratory of High Performance Scientific ComputationXihua UniversityChengdu 610039China St.Petersburg State University 7/9 Univrsieskaya nab.St.Petersburg 199034Russia

We develop a research of spin currents in a^(23)Na spinor Bose–Einstein condensate(BEC)by applying a magnetic field *** spin current is successfully induced by the spin-dependent force arising from the magnetic field *** dynamics of the spin components under the magnetic force is *** study is promising to be extended to produce a longer spin-coherence and to enhance the sensitivity of the spin-mixing interferometry in a spinor BEC.

关键词： spinor Bose-Einstein condensate spin current

Adsorption of Cd(Ⅱ) from acidic aqueous solutions by tourmaline as a novel material

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Chinese Science Bulletin 2012年第24期57卷 3218-3225页

作者： WANG CuiPing WANG BaoLin LIU JingTing YU Li SUN HongWen wu jizhou Key Laboratory of Pollution Processes and Environmental Criteria of the Ministry of Education College of Environmental Science andEngineeringNankai UniversityTianjin 300071China

Batch experiments were conducted to investigate the behavior and mechanisms for the adsorption of Cd(Ⅱ) from aqueous solutions by tourmaline under acidic conditions. The results indicated that the adsorption of Cd(Ⅱ) significantly depend on the adsorption time, temperature, and the initial concentration of the metal ion. Furthermore, tourmaline had a very good adsorption capacity for Cd(Ⅱ) in acidic, neutral and alkaline aqueous solutions. This good adsorption capacity is attributed to the observation that tourmaline can automatically adjust the pH values of acidic (except pH 2.0 and 3.0), neutral or alkaline aqueous solutions to 6.4. Specifically, the removal capacity for Cd(Ⅱ) was higher at strongly acidic pH values (in contrast to industrial wastewater pH values) compared to that obtained for other types of adsorbents. Furthermore, the results obtained in this study showed good fits to the Langmuir and Freundlich adsorption isotherms. However, the Langmuir model fit better than the Freundlich model. The maximum uptake of Cd(Ⅱ) by tourmaline was 31.77, 33.11 and 40.16 mg/g at pH 4.0 at 15, 25 and 35°C, respectively. Therefore, tourmaline is an effective adsorbent for the removal of Cd(Ⅱ) from acidic aqueous solutions. In addition, the kinetics for the Cd(Ⅱ) adsorption by tourmaline closely followed the pseudo-second-order model. The thermodynamic parameters indicated that adsorption was feasible, spontaneous, and endothermic. Furthermore, the pH variation after adsorption, ζ-potential, metal ions desorbed and released, and FT-IR analysis indicated that the physisorption and chemisorption mechanisms of tourmaline for heavy metals. These mechanisms included water that was automatically polarized by tourmaline, the ion exchange process, and electropolar adsorption. Among the mechanisms, the automatic polarization of water caused by tourmaline is a unique adsorption mechanism for tourmaline.

关键词：酸性水溶液吸附时间镉(Ⅱ) 电气石 Langmuir模型 Freundlich模型碱性水溶液 Cd(Ⅱ)

滨海环境下水泥基材料有机硅防护涂层的研究进展

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建筑材料学报 2024年第4期27卷 332-342页

作者：李萌萌吴聪金祖权侯东帅陈际洲青岛理工大学土木工程学院山东青岛266525 青岛理工大学海洋环境混凝土技术教育部工程研究中心山东青岛266520 青岛市政集团山东青岛266071

有机硅涂料通过对侵蚀介质的传输抑制作用以及诱导结晶作用,赋予了水泥基体优越的表面防护效果,显著提升了混凝土结构的耐久性能与安全可靠性.本文归纳了有机硅涂料的分子结构特征及其对胶凝材料的作用机理,全面阐述了有机硅涂料对水泥... 详细信息

有机硅涂料通过对侵蚀介质的传输抑制作用以及诱导结晶作用,赋予了水泥基体优越的表面防护效果,显著提升了混凝土结构的耐久性能与安全可靠性.本文归纳了有机硅涂料的分子结构特征及其对胶凝材料的作用机理,全面阐述了有机硅涂料对水泥基材料耐久性能的提升效果,探讨和展望了有机硅涂料在工程应用中存在的主要问题以及未来发展趋势,旨在为水泥基材料耐久性防护的深入研究与应用提供重要的理论指导与工程参考.

关键词：有机硅涂料水泥基材料表面防护结晶作用抗侵蚀