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Design of Wide-Range High-Precision Cesium Oven Temperature Control System for Time-Keeping Cesium Beam Frequency Standards

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APPLIED SCIENCES-BASEL 2025年第3期15卷 1128-1128页

作者： Liu, Jie Li, Xiaofeng Li, Chao hu, xuwen Li, Qingyue Sun, Fuyu Zhang, Shougang Chinese Acad Sci Natl Time Serv Ctr 3 East Shuyuan Rd Xian 710600 Peoples R China Nanchang Univ Sch Phys & Mat Sci Nanchang 330031 Peoples R China Chinese Acad Sci Key Lab Time Reference & Applicat 3 East Shuyuan Rd Xian 710600 Peoples R China Univ Chinese Acad Sci Beijing 100049 Peoples R China

The temperature fluctuation of a cesium oven has a significant impact on the performance of time-keeping cesium beam frequency standards. We have designed a circuit system for the precise temperature control of the cesium oven used in it. The use of a 24-bit analog-to-digital converter ensures a temperature measurement resolution more than 0.5 mK within the working range. The digital PID algorithm guarantees the accuracy of error signal computation, and a 16-bit digital-to-analog converter improves the resolution of the control current adjustment. Ultimately, we achieved the goal of keeping the temperature fluctuation of the cesium oven to less than 4 mK within a working range of 120 degrees C. The results indicate that the circuit system effectively ensures the performance of the cesium beam frequency standard.

关键词： time-keeping cesium beam frequency standards cesium oven temperature control digital PID

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Combined Separated Oscillatory Fields Technique 37

Combined Separated Oscillatory Fields Technique

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37th European Frequency and Time Forum, EFTF 2024

作者： Sun, Fuyu Li, Chao hu, xuwen Zhang, Shougang National Time Service Center Chinese Academy of Sciences Xi'an China Chinese Academy of Sciences Key Laboratory of Time Reference and Applications Xi'an China

ISBN: (纸本)9798350354270

Ramsey's method of separated oscillatory fields (SOFs) has been originally used in beam magnetic resonance apparatuses, which leads to the establishment of atomic definition of time interval and frequency. Since then, various versions of the SOFs technique have been widely used for precise measurement of different physical quantities. Here, we present an alternative method to generate atomic beam magnetic resonance signals by combining two Ramsey cavities with phase differences of 0 and 1t. It is found that the strength of the resonance signals generated using this combined SOFs technique is approximately twice that of the resonance signals produced by the conventional SOFs techniques. In addition to generating stronger resonance, the combined Ramsey method eliminates the Rabi background superimposed on the Ramsey interference pattern without increasing the Ramsey signal linewidth. Thus, this technique serves a promising tool for high-precision measurements. © 2024 IEEE.

关键词： Velocity measurement

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A Study of the History of Hakka Mountain Song Education Transmission Based on Inheritance Historicity

A Study of the History of Hakka Mountain Song Education Tran...

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作者： xuwen hu Faculty of creative technology and Heritage Universiti Malaysia Kelantan

Among the folk music of China, the Hakka Mountain Folk Songs of Gannan are a unique system with a long history. Understanding the rich humanistic connotation of Hakka and its place in the spiritual life of the people is of far-reaching significance to the study of Hakka culture, Hakka language and the spiritual sentiment of Hakka people in Ganzhou;and to arouse people's awareness of the inheritance and protection of this precious cultural heritage which is on the verge of extinction. The distinctive local characteristics and folk features are fully expressed in the Hakka Mountain Folk Songs, and the local language and customs, local customs, artistic conditions, and political and cultural life are reflected in the Hakka Mountain Folk Songs in a very realistic way. In recent years, the academic community has paid more attention to the musical characteristics of the Hakka Mountain Folk Songs in Gannan, and the research has gained certain achievements. This paper will focus on the historical origin of Hakka Mountain Folk Songs in Gannan, the spiritual characteristics of Hakka people, the language of Hakka Mountain Folk Songs, the study of the musical characteristics of mountain songs and contemporary vocal works that successfully borrow from Hakka Mountain Folk Songs in Gannan. In the last part of the article, he writes some opinions about the inheritance and innovation of Gannan Hakka Mountain Folk Songs, which will help the creators to create more and better local music works and do their part to promote the inheritance of Gannan Hakka Mountain Folk Songs.

关键词： origin A Study of the History of Hakka Mountain Song Education Transmission Based on Inheritance Historicity

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A Compact Optically Pumped Cesium Beam Clock with a Differential Detection Scheme 37

A Compact Optically Pumped Cesium Beam Clock with a Differen...

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37th European Frequency and Time Forum, EFTF 2024

作者： Li, Chao Sun, Fuyu hu, xuwen Liu, Jie Li, Xiaofeng Zhang, Shougang National Time Service Center Chinese Academy of Sciences Xi'an China Chinese Academy of Sciences Key Laboratory of Time Reference and Applications Xi'an China

ISBN: (纸本)9798350354270

Compact optically pumped cesium beam clocks have become a focus in cesium clock research due to their high atomic utilization and excellent short-term frequency stability. However, stray light noise, one of the main noise sources, limits the stability improvement. In this paper, we present a compact optically pumped cesium clock that uses differential detection to reduce the impact of stray light on clock performance. It incorporates an additional fluorescence collector to capture stray light during detection and subtract it from the clock transition signal, effectively reducing stray light level. Consequently, this scheme significantly enhances the signal-to-noise ratio, improving the short-term frequency stability of the compact optically pumped cesium clock. © 2024 IEEE.

关键词： Frequency stability

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An Improved Design of Atomic-Beam Fluorescence Collector 37

An Improved Design of Atomic-Beam Fluorescence Collector

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37th European Frequency and Time Forum, EFTF 2024

作者： hu, xuwen Sun, Fuyu Li, Chao Liu, Jie Li, Xiaofeng Zhang, Shougang National Time Service Center Chinese Academy of Sciences Xi'an China Chinese Academy of Sciences Key Laboratory of Time Reference and Applications Xi'an China

ISBN: (纸本)9798350354270

Efficient fluorescence detection is crucial in the field of precision spectral analysis. This paper presents an improved design of an atomic-beam fluorescence collector that utilizes the convergence characteristics of ellipsoidal surfaces and the reflection characteristics of spherical surfaces. It calculates the parameter relationship for achieving full-angle fluorescence collection. The study fine-tunes the structural parameters and simulates the fluorescence collection efficiency and losses under different conditions when emitting from a non-ideal point light source. The improved fluorescence collector captures photons with nearly 4n solid angle coverage, allowing photons to be reflected at most twice before reaching the photo detector, thereby increasing collection efficiency. This improved collector can be used in various fields for detecting weak fluorescence signals. © 2024 IEEE.

关键词： Fluorescence microscopy

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A Curved Four-Conductor Assembly with Larger Uniform Region

A Curved Four-Conductor Assembly with Larger Uniform Region

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2023 Joint Conference of the European Frequency and Time Forum and IEEE International Frequency Control Symposium, EFTF/IFCS 2023

作者： Li, Chao hu, xuwen Sun, Fuyu Liu, Jie Li, Xiaofeng Zhang, Shougang National Time Service Center Chinese Academy of Sciences Xi'an China University of Chinese Academy of Sciences Beijing China

ISBN: (纸本)9798350311426

Most atomic physics setups require a uniform static magnetic field to define a quantization axis. The straight four-conductor assembly has been proven to be a useful structure for producing such a uniform static magnetic field. Here, we present an improved four-conductor assembly, where each conductor consists of one straight section and two curved sections. This hybrid structure arrangement offers more degrees of freedom than the conventional straight four-conductor assembly, enabling a larger uniform field region and better field spatial uniformity. The modified magnetic field generation structure can be used in many fields of atomic precision spectroscopy. © 2023 IEEE.

关键词： curved section four-conductor modified four-conductor static magnetic field uniformity

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Combined Separated Oscillatory Fields Technique

Combined Separated Oscillatory Fields Technique

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European Frequency and Time Forum (EFTF)

作者： Fuyu Sun Chao Li xuwen hu Shougang Zhang National Time Service Center Chinese Academy of Sciences Xi'an China Key Laboratory of Time Reference and Applications Chinese Academy of Sciences Xi'an China

ISBN: (数字)9798350354270

ISBN: (纸本)9798350354287

关键词： Atomic measurements Time-frequency analysis Magnetic field measurement Atomic beams Magnetic resonance Europe Interference

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Functional differentiation analysis of duplicated mlpha gene in Oujiang color common carp (Cyprinus carpio var. color) on colour formation

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AQUACULTURE RESEARCH 2021年第10期52卷 4565-4573页

作者： hu, xuwen Chen, Honglin Yu, Luwei Chen, Xiaowen Mandal, Biplab Kumar Wang, Jun Wang, Chenghui Shanghai Ocean Univ Natl Demonstrat Ctr Expt Fisheries Sci Educ Key Lab Freshwater Aquat Genet Resources Shanghai Engn Res Ctr AquacultureMinist Agr & Ru Shanghai Peoples R China Zhejiang Acad Agr Sci Inst Hydrobiol Hangzhou Peoples R China

Melanophilin (mlph) encodes a subfamily of Rab effector proteins which is an important gene for the transportation of mature melanosomes. Duplicated mlpha gene (mlpha1 and mlpha2) of Oujiang color common carp (Cyprinus carpio var. color) was firstly identified in the present study, which includes an open reading frame (ORF) length of 1713 bp and 1536 bp, encoding 570 and 511 amino acids respectively. Spatial and temporal expression, in situ hybridization and disruption experiments were conducted to explore the functional differentiation of mlpha (mlpha1 and mlpha2) during the melanin transport process of Oujiang color common carp. Distinct expression pattern of mlpha1 and mlpha2 were identified, and the expression level of mlpha1 in red skin of whole red with black patch (RB-R) and white skin of whole white with black patch (WB-W) was significantly lower than their corresponding black skin of RB and WB (RB-B and WB-B). On the contrary, the expression level of mlpha2 in RB-R and WB-W was significantly higher than their corresponding black skin (RB-B and WB-B). Mlpha2 was highly expressed in the "Whole red" (WR) skin, and mlpha1 was lowly expressed in the WR. Meanwhile, abundant positive ISH hybridization signals of mlpha2 were identified in 5 days post-hatch larvae (5dph) of WR. The high mutation rate of mlpha1 and mlpha2 genes resulted in a significant dilution phenotype, while the low mutation rate led to partial skin to appear discoloration phenomenon of Oujiang color common carp (RB and WB). The findings indicated that mlpha is an indispensable functional gene that may participate in the transportation of pigments and functional differentiation may exist between mlpha1 and mlpha2 after duplication. Mlpha1 may be mainly involved in the transportation of melanin, and mlpha2 may also participate in the transportation of other pigments.

关键词： CRISPR Cas9 functional differentiation melanophilin melanosomes Oujiang color common carp

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An Improved Design of Atomic-Beam Fluorescence Collector

An Improved Design of Atomic-Beam Fluorescence Collector

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European Frequency and Time Forum (EFTF)

作者： xuwen hu Fuyu Sun Chao Li Jie Liu Xiaofeng Li Shougang Zhang National Time Service Center Chinese Academy of Sciences Xi'an China Key Laboratory of Time Reference and Applications Chinese Academy of Sciences Xi'an China

ISBN: (数字)9798350354270

ISBN: (纸本)9798350354287

关键词： Time-frequency analysis Europe Detectors Fluorescence Solids Reflection Structural engineering Spectral analysis Photonics Light sources

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A Compact Optically Pumped Cesium Beam Clock with a Differential Detection Scheme

A Compact Optically Pumped Cesium Beam Clock with a Differen...

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European Frequency and Time Forum (EFTF)

作者： Chao Li Fuyu Sun xuwen hu Jie Liu Xiaofeng Li Shougang Zhang National Time Service Center Chinese Academy of Sciences Xi'an China Key Laboratory of Time Reference and Applications Chinese Academy of Sciences Xi'an China

ISBN: (数字)9798350354270

ISBN: (纸本)9798350354287

关键词： Time-frequency analysis Atom optics Stray light Laser stability Cesium Optical pumping Optical noise Laser beams Optical beams Clocks

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