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基于ISSR和TRAP分子标记的东北地区栽培黑木耳遗传多样性研究
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作者 焦枥禾 张丕奇 +3 位作者 王凤利 张秀丰 岳欣 戴肖东 《种子》 北大核心 2024年第5期112-118,共7页
为探究东北地区黑木耳栽培菌株的遗传多样性及亲缘关系,采用ISSR和TRAP分子标记对50株栽培黑木耳菌株进行遗传多样性分析。利用22条高多态性、高分辨率的ISSR和TRAP分子标记引物,对栽培黑木耳进行了DNA扩增。结果表明,黑木耳ISSR和TRAP... 为探究东北地区黑木耳栽培菌株的遗传多样性及亲缘关系,采用ISSR和TRAP分子标记对50株栽培黑木耳菌株进行遗传多样性分析。利用22条高多态性、高分辨率的ISSR和TRAP分子标记引物,对栽培黑木耳进行了DNA扩增。结果表明,黑木耳ISSR和TRAP标记谱带多态性较高,分别占89.58%和84.71%,遗传相似系数为0.53~1.00;在ISSR标记的聚类图中相似系数大于0.96的菌株占44.0%,TRAP标记的聚类图中相似系数大于0.96的菌株占54.0%;STRUCTURE聚类结果显示,50株菌株可分为四大类;遗传多样性分析结果表明,东北地区黑木耳栽培菌株的遗传多样性主要来源于群体间,黑木耳栽培菌株的遗传多样性欠丰富,生产菌种资源的同质化较为突出。 展开更多
关键词 黑木耳 遗传多样性 分子标记 ISSR TRAP
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Neutrophil extracellular traps mediate neuro-immunothrombosis 被引量:1
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作者 Jianbo Lou Jianning Zhang +1 位作者 Quanjun Deng Xin Chen 《Neural Regeneration Research》 SCIE CAS CSCD 2024年第8期1734-1740,共7页
Neutrophil extracellular traps are primarily composed of DNA and histones and are released by neutrophils to promote inflammation and thrombosis when stimulated by various inflammato ry reactions.Neutrophil extracellu... Neutrophil extracellular traps are primarily composed of DNA and histones and are released by neutrophils to promote inflammation and thrombosis when stimulated by various inflammato ry reactions.Neutrophil extracellular trap formation occurs through lytic and non-lytic pathways that can be further classified by formation mechanisms.Histones,von Willebrand factor,fibrin,and many other factors participate in the interplay between inflammation and thrombosis.Neuroimmunothrombosis summarizes the intricate interplay between inflammation and thrombosis during neural development and the pathogenesis of neurological diseases,providing cutting-edge insights into post-neurotrauma thrombotic events.The blood-brain barrier defends the brain and spinal cord against external assaults,and neutrophil extracellular trap involvement in blood-brain barrier disruption and immunothrombosis contributes substantially to secondary injuries in neurological diseases.Further research is needed to understand how neutrophil extracellular traps promote blood-brain barrier disruption and immunothrombosis,but recent studies have demonstrated that neutrophil extracellular traps play a crucial role in immunothrombosis,and identified modulators of neuro-immunothrombosis.However,these neurological diseases occur in blood vessels,and the mechanisms are unclear by which neutrophil extracellular traps penetrate the blood-brain barrier to participate in immunothrombosis in traumatic brain injury.This review discusses the role of neutrophil extracellular traps in neuro-immunothrombosis and explores potential therapeutic interventions to modulate neutrophil extracellular traps that may reduce immunothrombosis and improve traumatic brain injury outcomes. 展开更多
关键词 inflammation neuro-immunothrombosis neurologic diseases NEUROTRAUMA neutrophil extracellular traps PLATELET THROMBOSIS traumatic brain injury
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New approach to measuring topological phase transitions utilizing Floquet technology
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作者 Xue-Ying Yang Wei Wu Ping-Xing Chen 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第9期282-288,共7页
The Floquet technique provides a novel anomalous topological phase for non-equilibrium phase transitions.Based on the high symmetry of the quantum anomalous Hall model,the findings suggest a one-to-one correspondence ... The Floquet technique provides a novel anomalous topological phase for non-equilibrium phase transitions.Based on the high symmetry of the quantum anomalous Hall model,the findings suggest a one-to-one correspondence between the average spin texture and the Floquet quasi-energy spectrum.A new approach is proposed to directly measure the quasienergy spectrum,replacing previous measurements of the average spin texture.Finally,we proposed a reliable experimental scheme based on ion trap platforms.This scheme markedly reduces the measurement workload,improves the measurement fidelity,and is applicable to multiple platforms such as cold atoms and nuclear magnetic resonance. 展开更多
关键词 TOPOLOGICAL phase TRANSITION FLOQUET technique ION TRAP
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Physical insights into trapping effects on vertical GaN-on-Si trench MOSFETs from TCAD
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作者 NicolòZagni Manuel Fregolent +9 位作者 Andrea Del Fiol Davide Favero Francesco Bergamin Giovanni Verzellesi Carlo De Santi Gaudenzio Meneghesso Enrico Zanoni Christian Huber Matteo Meneghini Paolo Pavan 《Journal of Semiconductors》 EI CAS CSCD 2024年第3期45-52,共8页
Vertical GaN power MOSFET is a novel technology that offers great potential for power switching applications.Being still in an early development phase,vertical GaN devices are yet to be fully optimized and require car... Vertical GaN power MOSFET is a novel technology that offers great potential for power switching applications.Being still in an early development phase,vertical GaN devices are yet to be fully optimized and require careful studies to foster their development.In this work,we report on the physical insights into device performance improvements obtained during the development of vertical GaN-on-Si trench MOSFETs(TMOS’s)provided by TCAD simulations,enhancing the dependability of the adopted process optimization approaches.Specifically,two different TMOS devices are compared in terms of transfer-curve hysteresis(H)and subthreshold slope(SS),showing a≈75%H reduction along with a≈30%SS decrease.Simulations allow attributing the achieved improvements to a decrease in the border and interface traps,respectively.A sensitivity analysis is also carried out,allowing to quantify the additional trap density reduction required to minimize both figures of merit. 展开更多
关键词 vertical GaN trench MOSFET SiO_(2) interface traps border traps HYSTERESIS BTI
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Emission and capture characteristics of deep hole trap in n-GaN by optical deep level transient spectroscopy
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作者 Jin Sui Jiaxiang Chen +3 位作者 Haolan Qu Yu Zhang Xing Lu Xinbo Zou 《Journal of Semiconductors》 EI CAS CSCD 2024年第3期58-63,共6页
Emission and capture characteristics of a deep hole trap(H1)in n-GaN Schottky barrier diodes(SBDs)have been investigated by optical deep level transient spectroscopy(ODLTS).Activation energy(Eemi)and capture cross-sec... Emission and capture characteristics of a deep hole trap(H1)in n-GaN Schottky barrier diodes(SBDs)have been investigated by optical deep level transient spectroscopy(ODLTS).Activation energy(Eemi)and capture cross-section(σ_(p))of H1 are determined to be 0.75 eV and 4.67×10^(−15)cm^(2),respectively.Distribution of apparent trap concentration in space charge region is demonstrated.Temperature-enhanced emission process is revealed by decrease of emission time constant.Electricfield-boosted trap emission kinetics are analyzed by the Poole−Frenkel emission(PFE)model.In addition,H1 shows point defect capture properties and temperature-enhanced capture kinetics.Taking both hole capture and emission processes into account during laser beam incidence,H1 features a trap concentration of 2.67×10^(15)cm^(−3).The method and obtained results may facilitate understanding of minority carrier trap properties in wide bandgap semiconductor material and can be applied for device reliability assessment. 展开更多
关键词 GaN deep level transient spectroscopy minority carrier trap time constant trap concentration
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Compact magneto-optical traps using planar optics
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作者 Zhi Tan Bo Lu +1 位作者 Chengyin Han Chaohong Lee 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第9期93-108,共16页
Magneto-optical traps (MOTs) composed of magnetic fields and light fields have been widely utilized to cool andconfine microscopic particles. Practical technology applications require miniaturized MOTs. The advancemen... Magneto-optical traps (MOTs) composed of magnetic fields and light fields have been widely utilized to cool andconfine microscopic particles. Practical technology applications require miniaturized MOTs. The advancement of planaroptics has promoted the development of compact MOTs. In this article, we review the development of compact MOTs basedon planar optics. First, we introduce the standardMOTs. We then introduce the gratingMOTs with micron structures, whichhave been used to build cold atomic clocks, cold atomic interferometers, and ultra-cold sources. Further, we introducethe integrated MOTs based on nano-scale metasurfaces. These new compact MOTs greatly reduce volume and powerconsumption, and provide new opportunities for fundamental research and practical applications. 展开更多
关键词 MAGNETO-OPTICAL TRAP (MOT) PLANAR OPTICS GRATING MOT metasurface MOT
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Top Five Stories of the Cellular Landscape and Therapies of Atherosclerosis:Current Knowledge and Future Perspectives
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作者 Qi PAN Cheng CHEN Yue-jin YANG 《Current Medical Science》 SCIE CAS 2024年第1期1-27,共27页
Atherosclerosis(AS)is characterized by impairment and apoptosis of endothelial cells,continuous systemic and focal inflammation and dysfunction of vascular smooth muscle cells,which is documented as the traditional ce... Atherosclerosis(AS)is characterized by impairment and apoptosis of endothelial cells,continuous systemic and focal inflammation and dysfunction of vascular smooth muscle cells,which is documented as the traditional cellular paradigm.However,the mechanisms appear much more complicated than we thought since a bulk of studies on efferocytosis,transdifferentiation and novel cell death forms such as ferroptosis,pyroptosis,and extracellular trap were reported.Discovery of novel pathological cellular landscapes provides a large number of therapeutic targets.On the other side,the unsatisfactory therapeutic effects of current treatment with lipid-lowering drugs as the cornerstone also restricts the efforts to reduce global AS burden.Stem cell-or nanoparticle-based strategies spurred a lot of attention due to the attractive therapeutic effects and minimized adverse effects.Given the complexity of pathological changes of AS,attempts to develop an almighty medicine based on single mechanisms could be theoretically challenging.In this review,the top stories in the cellular landscapes during the initiation and progression of AS and the therapies were summarized in an integrated perspective to facilitate efforts to develop a multi-targets strategy and fill the gap between mechanism research and clinical translation.The future challenges and improvements were also discussed. 展开更多
关键词 ATHEROSCLEROSIS TRANSDIFFERENTIATION extracellular traps EFFEROCYTOSIS stem cell nanoparticles
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Pressure-Induced Distinct Self-Trapped Exciton Emission in Sb^(3+)-Doped Cs_(2)NaInCl_(6)Double Perovskite
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作者 冯友佳 陈亚平 +10 位作者 王乐瑶 王家祥 常断华 袁亦方 武敏 付瑞净 张丽丽 王庆林 王凯 郭海中 王玲瑞 《Chinese Physics Letters》 SCIE EI CAS CSCD 2024年第6期18-43,共26页
The Cs_(2)NaInCl_(6) double perovskite is one of the most promising lead-free perovskites due to its exceptional stability and straightforward synthesis.However,it faces challenges related to inefficient photoluminesc... The Cs_(2)NaInCl_(6) double perovskite is one of the most promising lead-free perovskites due to its exceptional stability and straightforward synthesis.However,it faces challenges related to inefficient photoluminescence.Doping and high pressure are employed to tailor the optical properties of Cs_(2)NaInCl_(6).Herein,Sb^(3+)doped Cs_(2)NaInCl_(6)(Sb^(3+):Cs_(2)NaInCl_(6)) was synthesized and it exhibits blue emission with a photoluminescence quantum yield of up to 37.3%.Further,by employing pressure tuning,a blue stable emission under a very wide range from 2.7 GPa to 9.8 GPa is realized in Sb^(3+):Cs_(2)NaInCl_(6).Subsequently,the emission intensity of Sb^(3+):Cs_(2)NaInCl_(6) experiences a significant increase(3.3 times)at 19.0 GPa.It is revealed that the pressure-induced distinct emissions can be attributed to the carrier self-trapping and detrapping between Cs_(2)NaInCl_(6) and Sb^(3+).Notably,the lattice compression in the cubic phase inevitably modifies the band gap of Sb^(3+):Cs_(2)NaInCl_(6).Our findings provide valuable insights into effects of the high pressure in further boosting unique emission characteristics but also offer promising opportunities for development of doped double perovskites with enhanced optical functionalities. 展开更多
关键词 synthesis PEROVSKITE TRAPPING
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Theoretical investigations of population trapping phenomena in atomic four-color,three-step photoionization scheme
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作者 卢肖勇 孙亚鹏 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第3期333-340,共8页
The four-color three-step selective photoionization process of atom is very important in laser isotope separation technology.The population trapping phenomena and their influences are studied theoretically in monochro... The four-color three-step selective photoionization process of atom is very important in laser isotope separation technology.The population trapping phenomena and their influences are studied theoretically in monochromatic and non-monochromatic laser fields based on the density matrix theory in this work.Time evolutions of the photoionization properties of the four-color,three-step process are given.The population trapping effects occur intensely in monochromatic excitation,while it gradually turns weak as the laser bandwidth increases.The effects of bandwidth,Rabi frequency,time delay,and frequency detuning on the population trapping effect are investigated in monochromatic and non-monochromatic laser fields.The effects of laser process parameters and atomic parameters on the effective selective photoionization are also discussed.The ionization probability and selectivity factors,as evaluation indexes,are difficult to improve synchronously by adjusting systematic parameters.Besides,the existence of metastable state may play a negative role when its population is low enough. 展开更多
关键词 population trapping metastable state selective photoionization laser bandwidth
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In situ calibrated angle between the quantization axis and the propagating direction of the light field for trapping neutral atoms
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作者 郭瑞军 何晓东 +7 位作者 盛诚 王坤鹏 许鹏 刘敏 王谨 孙晓红 曾勇 詹明生 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第2期318-323,共6页
The recently developed magic-intensity trapping technique of neutral atoms efficiently mitigates the detrimental effect of light shifts on atomic qubits and substantially enhances the coherence time. This technique re... The recently developed magic-intensity trapping technique of neutral atoms efficiently mitigates the detrimental effect of light shifts on atomic qubits and substantially enhances the coherence time. This technique relies on applying a bias magnetic field precisely parallel to the wave vector of a circularly polarized trapping laser field. However, due to the presence of the vector light shift experienced by the trapped atoms, it is challenging to precisely define a parallel magnetic field, especially at a low bias magnetic field strength, for the magic-intensity trapping of85Rb qubits. In this work, we present a method to calibrate the angle between the bias magnetic field and the trapping laser field with the compensating magnetic fields in the other two directions orthogonal to the bias magnetic field direction. Experimentally, with a constantdepth trap and a fixed bias magnetic field, we measure the respective resonant frequencies of the atomic qubits in a linearly polarized trap and a circularly polarized one via the conventional microwave Rabi spectra with different compensating magnetic fields and obtain the corresponding total magnetic fields via the respective resonant frequencies using the Breit–Rabi formula. With known total magnetic fields, the angle is a function of the other two compensating magnetic fields.Finally, the projection value of the angle on either of the directions orthogonal to the bias magnetic field direction can be reduced to 0(4)° by applying specific compensating magnetic fields. The measurement error is mainly attributed to the fluctuation of atomic temperature. Moreover, it also demonstrates that, even for a small angle, the effect is strong enough to cause large decoherence of Rabi oscillation in a magic-intensity trap. Although the compensation method demonstrated here is explored for the magic-intensity trapping technique, it can be applied to a variety of similar precision measurements with trapped neutral atoms. 展开更多
关键词 quantization axis trapping laser ANGLE compensating magnetic fields
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Review on the design of high-strength and hydrogen-embrittlement-resistant steels
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作者 Zhiyu Du Rongjian Shi +2 位作者 Xingyu Peng Kewei Gao Xiaolu Pang 《International Journal of Minerals,Metallurgy and Materials》 SCIE EI CAS CSCD 2024年第7期1572-1589,共18页
Given the carbon peak and carbon neutrality era,there is an urgent need to develop high-strength steel with remarkable hydrogen embrittlement resistance.This is crucial in enhancing toughness and ensuring the utilizat... Given the carbon peak and carbon neutrality era,there is an urgent need to develop high-strength steel with remarkable hydrogen embrittlement resistance.This is crucial in enhancing toughness and ensuring the utilization of hydrogen in emerging iron and steel materials.Simultaneously,the pursuit of enhanced metallic materials presents a cross-disciplinary scientific and engineering challenge.Developing high-strength,toughened steel with both enhanced strength and hydrogen embrittlement(HE)resistance holds significant theoretical and practical implications.This ensures secure hydrogen utilization and further carbon neutrality objectives within the iron and steel sector.Based on the design principles of high-strength steel HE resistance,this review provides a comprehensive overview of research on designing surface HE resistance and employing nanosized precipitates as intragranular hydrogen traps.It also proposes feasible recommendations and prospects for designing high-strength steel with enhanced HE resistance. 展开更多
关键词 hydrogen embrittlement surface design hydrogen traps nanosized precipitates
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Optical trapping capability of tornado circular Pearcey beams
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作者 刘娜娜 唐晓莹 +1 位作者 刘舜禹 梁毅 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第5期401-407,共7页
We systemically investigate optical trapping capability of a kind of tornado waves on Rayleigh particles.Such tornado waves are named as tornado circular Pearcey beams(TCPBs)and produced by combining two circular Pear... We systemically investigate optical trapping capability of a kind of tornado waves on Rayleigh particles.Such tornado waves are named as tornado circular Pearcey beams(TCPBs)and produced by combining two circular Pearcey beams with different radii.Our theoretical exploration delves into various aspects,including the propagation dynamics,energy flux,orbital angular momentum,trapping force,and torque characteristics of TCPBs.The results reveal that the orbital angular momentum,trapping force,and torque of these beams can be finely tuned through the judicious manipulation of their topological charges(l_(1)and l_(2)).Notably,we observe a precise control mechanism wherein the force diminishes with|l_(1)+l_(2)|and|l_(1)-l_(2)|,while the torque exhibits enhancement by decreasing solely with|l_(1)+l_(2)|or increasing with|l_(1)-l_(2)|.These results not only provide quantitative insights into the optical trapping performance of TCPBs but also serve as a valuable reference for the ongoing development of innovative photonic tools. 展开更多
关键词 trapping capability tornado beams autofocusing
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Large-scale particle trapping by acoustic vortices with a continuously variable topological charge
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作者 庄昊霏 张清源 +2 位作者 胡格昊 王青东 杜立彬 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第7期398-406,共9页
Strengthened directivity with higher-order side lobes can be generated by the transducer with a larger radius at a higher frequency. The multi-annular pressure distributions are displayed in the cross-section of the a... Strengthened directivity with higher-order side lobes can be generated by the transducer with a larger radius at a higher frequency. The multi-annular pressure distributions are displayed in the cross-section of the acoustic vortices(AVs)which are formed by side lobes. In the near field, particles can be trapped in the valley region between the two annuli of the pressure peak, and cannot be moved to the vortex center. In this paper, a trapping method based on a sector transducer array is proposed, which is characterized by the continuously variable topological charge(CVTC). This acoustic field can not only enlarge the range of particle trapping but also improve the aggregation degree of the trapped particles. In the experiments, polyethylene particles with a diameter of 0.2 mm are trapped into the multi-annular valleys by the AV with a fixed topological charge. Nevertheless, by applying the CVTC, particles outside the radius of the AV can cross the pressure peak successfully and move to the vortex center. Theoretical studies are also verified by the experimental particles trapping using the AV with the continuous variation of three topological charges, and suggest the potential application of large-scale particle trapping in biomedical engineering. 展开更多
关键词 acoustic vortices sector transducer array trapping particle continuously variable topological charge
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Efficient loading of cesium atoms in a magnetic levitated dimple trap
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作者 张国庆 冯国胜 +2 位作者 李玉清 武寄洲 马杰 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第2期324-328,共5页
We report a detailed study of magnetically levitated loading of ultracold ^(133)Cs atoms in a dimple trap.The atomic sample was produced in a combined red-detuned optical dipole trap and dimple trap formed by two smal... We report a detailed study of magnetically levitated loading of ultracold ^(133)Cs atoms in a dimple trap.The atomic sample was produced in a combined red-detuned optical dipole trap and dimple trap formed by two small waist beams crossing a horizontal plane.The magnetic levitation for the ^(133)Cs atoms forms an effective potential for a large number of atoms in a high spatial density.Dependence of the number of atoms loaded and trapped in the dimple trap on the magnetic field gradient and bias field is in good agreement with the theoretical analysis.This method has been widely used to obtain the Bose–Einstein condensation atoms for many atomic species. 展开更多
关键词 ultracold atom magnetic levitation dimple trap
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Building and characterizing a stylus ion-trap system
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作者 崔太豪 魏雅琪 +8 位作者 李冀 袁泉 戴双晴 李沛东 周飞 张建奇 郑驻军 陈亮 冯芒 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第4期122-127,共6页
Cold trapped ions can be excellent sensors for ultra-precision detection of physical quantities,which strongly depends on the measurement situation at hand.The stylus ion trap,formed by two concentric cylinders over a... Cold trapped ions can be excellent sensors for ultra-precision detection of physical quantities,which strongly depends on the measurement situation at hand.The stylus ion trap,formed by two concentric cylinders over a ground plane,holds the promise of relatively simple structure and larger solid angle for optical access and fluorescence collection in comparison with the conventional ion traps.Here we report our fabrication and characterization of the first stylus ion trap constructed in China,aiming for studying quantum optics and sensing weak electric fields in the future.We have observed the stable confinement of the ion in the trapping potential for more than two hours and measured the heating rate of the trap to be dε/dt=7.10±0.13 meV/s by the Doppler recooling method.Our work starts a way to building practical quantum sensors with high efficiency of optical collection and with ultimate goal for contributing to future quantum information technology. 展开更多
关键词 stylus ion trap electric-field noises Doppler recooling method heating rate
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Doped low-density parity-check codes
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作者 Yong Li Rui Liu +3 位作者 Xianlong Jiao Youqiang Hu Zhen Luo Francis C.M.Lau 《Digital Communications and Networks》 SCIE CSCD 2024年第1期217-226,共10页
In this paper,we propose a doping approach to lower the error floor of Low-Density Parity-Check(LDPC)codes.The doping component is a short block code in which the information bits are selected from the coded bits of t... In this paper,we propose a doping approach to lower the error floor of Low-Density Parity-Check(LDPC)codes.The doping component is a short block code in which the information bits are selected from the coded bits of the dominant trapping sets of the LDPC code.Accordingly,an algorithm for selecting the information bits of the short code is proposed,and a specific two-stage decoding algorithm is presented.Simulation results demonstrate that the proposed doped LDPC code achieves up to 2.0 dB gain compared with the original LDPC code at a frame error rate of 10^(-6)Furthermore,the proposed design can lower the error floor of original LDPC Codes. 展开更多
关键词 LDPC codes Doped LDPC codes Tanner graph Quadratic residue codes Trapping sets
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A Novel Three-stage Tectonic Model for Mississippi Valleytype Zn-Pb Deposits in Orogenic Fold-and-Thrust Belts
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作者 SONG Yucai 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2024年第4期843-849,共7页
Mississippi Valley-type(MVT) Zn-Pb deposits predominantly form within both orogenic forelands and fold-andthrust belts, yet the mineralization process within the latter tectonic setting remains inadequately understood... Mississippi Valley-type(MVT) Zn-Pb deposits predominantly form within both orogenic forelands and fold-andthrust belts, yet the mineralization process within the latter tectonic setting remains inadequately understood. This study, through a comprehensive review of MVT deposits across global fold-and-thrust belts, introduces a novel model elucidating the mineralization process in the context of tectonic belt evolution. It is demonstrated that during the stage Ⅰ, regional compression is introduced by early stages of plate convergence, causing the folding and thrusting and creating structural or lithological traps such as evaporite diapirs and unconformity-related carbonate dissolution-collapse structures. Thereafter, in stage Ⅱ, hydrocarbons begin to migrate and accumulate within these traps, where reduced sulfur is generated through thermochemical or bacterial sulfate reduction concurrent with or preceding Zn-Pb mineralization. In the subsequent stage Ⅲ, as plate convergence persists, the regional stress transitions from compression to transpression or extension. Under these conditions, steeply-dipping extensional faults are generated, facilitating the ascent of metalliferous brines into early-formed structural or lithological traps. Precipitation of Zn and Pb sulfides occurs through the mixing of Zn-Pb-transporting fluids with pre-existing reduced sulfur or by interaction with hydrocarbons. 展开更多
关键词 Mississippi Valley-type Zn-Pb deposits fold-and-thrust belts tectonic model structural or lithological traps extensional faults
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Atomic transport dynamics in crossed optical dipole trap
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作者 彭鹏 张正熙 +5 位作者 樊耀塬 殷国玲 毛德凯 陈徐宗 熊炜 周小计 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第7期293-301,共9页
We study the dynamical evolution of cold atoms in crossed optical dipole trap theoretically and experimentally. The atomic transport process is accompanied by two competitive kinds of physical mechanics, atomic loadin... We study the dynamical evolution of cold atoms in crossed optical dipole trap theoretically and experimentally. The atomic transport process is accompanied by two competitive kinds of physical mechanics, atomic loading and atomic loss.The loading process normally is negligible in the evaporative cooling experiment on the ground, while it is significant in preparation of ultra-cold atoms in the space station. Normally, the atomic loading process is much weaker than the atomic loss process, and the atomic number in the central region of the trap decreases monotonically, as reported in previous research. However, when the atomic loading process is comparable to the atomic loss process, the atomic number in the central region of the trap will initially increase to a maximum value and then slowly decrease, and we have observed the phenomenon first. The increase of atomic number in the central region of the trap shows the presence of the loading process, and this will be significant especially under microgravity conditions. We build a theoretical model to analyze the competitive relationship, which coincides with the experimental results well. Furthermore, we have also given the predicted evolutionary behaviors under different conditions. This research provides a solid foundation for further understanding of the atomic transport process in traps. The analysis of loading process is of significant importance for preparation of ultra-cold atoms in a crossed optical dipole trap under microgravity conditions. 展开更多
关键词 cold atom crossed optical dipole trap transport process
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Magnetic field regression using artificial neural networks for cold atom experiments
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作者 陈子霆 黃建陶 +6 位作者 Bojeong Seo 黄明琛 Mithilesh K.Parit 何逸飞 甄浩廷 Jensen Li Gyu-Boong Jo 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第2期46-51,共6页
Accurately measuring magnetic fields is essential for magnetic-field sensitive experiments in areas like atomic,molecular,and optical physics,condensed matter experiments,and other areas.However,since many experiments... Accurately measuring magnetic fields is essential for magnetic-field sensitive experiments in areas like atomic,molecular,and optical physics,condensed matter experiments,and other areas.However,since many experiments are often conducted in an isolated environment that is inaccessible to experimentalists,it can be challenging to accurately determine the magnetic field at the target location.Here,we propose an efficient method for detecting magnetic fields with the assistance of an artificial neural network(NN).Instead of measuring the magnetic field directly at the desired location,we detect fields at several surrounding positions,and a trained NN can accurately predict the magnetic field at the target location.After training,we achieve a below 0.3%relative prediction error of magnetic field magnitude at the center of the vacuum chamber,and successfully apply this method to our erbium quantum gas apparatus for accurate calibration of magnetic field and long-term monitoring of environmental stray magnetic field.The demonstrated approach significantly simplifies the process of determining magnetic fields in isolated environments and can be applied to various research fields across a wide range of magnetic field magnitudes. 展开更多
关键词 ultracold gases trapped gases measurement methods and instrumentation
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Significance of including lid thickness and particle shape factor in numerical modeling for prediction of particle trap efficiency of invert trap
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作者 Salman Beg Deo Raj Kaushal 《Water Science and Engineering》 EI CAS CSCD 2024年第2期166-176,共11页
Sediment accumulation on the bed of open sewers and drains reduces hydraulic efficiency and can cause localized flooding.Slotted invert traps installed underneath the bed of open sewers and drains can eliminate sedime... Sediment accumulation on the bed of open sewers and drains reduces hydraulic efficiency and can cause localized flooding.Slotted invert traps installed underneath the bed of open sewers and drains can eliminate sediment build-up by catching sediment load.Previous three-dimensional(3D)computational studies have examined the particle trapping performance of invert traps of different shapes and depths under varied sediment and flow conditions,considering particles as spheres.For two-dimensional and 3D numerical modeling,researchers assumed the lid geometry to be a thin line and a plane,respectively.In this 3D numerical study,the particle trapping efficiency of a slotted irregular hexagonal invert trap fitted at the flume bottom was examined by incorporating the particle shape factor of non-spherical sewage solid particles and the thicknesses of upstream and downstream lids over the trap in the discrete phase model of the ANSYS Fluent 2020 R1 software.The volume of fluid(VOF)and the realizable k-turbulence models were used to predict the velocity field.The two-dimensional particle image velocimetry(PIV)was used to measure the velocity field inside the invert trap.The results showed that the thicknesses of upstream and downstream lids affected the velocity field and turbulent kinetic energy at all flow depths.The joint impact of the particle shape factor and lid thickness on the trap efficiency was significant.When both the lid thickness and particle shape factor were considered in the numerical modeling,trap efficiencies were underestimated,with relative errors of-8.66%to-0.65%in comparison to the experimental values of Mohsin and Kaushal(2017).They were also lower than the values predicted by Mohsin and Kaushal(2017),which showed an overall overestimation with errors of-2.3%to 17.4%. 展开更多
关键词 Invert trap Lid thickness Particle image velocimetry Particle shape factor Turbulent kinetic energy Scanning electron microscope
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