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BG-Trap法与双层叠帐法对登革热媒介白纹伊蚊监测效果的比较
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作者 田野 褚宏亮 +4 位作者 吴治明 张守刚 曹淦 葛小伍 黄立业 《寄生虫与医学昆虫学报》 CAS 2024年第1期28-32,共5页
目的比较BG-trap法与双层叠帐法对登革热媒介白纹伊蚊的监测效果,进一步探讨BG-trap法用于登革热媒介伊蚊监测的可能性,为制定更有效的登革热防控策略提供参考依据。方法实验选取江苏省3个设区市的6个户外监测点,于8—9月的3天时间中,... 目的比较BG-trap法与双层叠帐法对登革热媒介白纹伊蚊的监测效果,进一步探讨BG-trap法用于登革热媒介伊蚊监测的可能性,为制定更有效的登革热防控策略提供参考依据。方法实验选取江苏省3个设区市的6个户外监测点,于8—9月的3天时间中,分别于每日16:00-16:30、17:00-17:30、18:00-18:30三个时段同步开展BG-Trap法和双层叠帐法监测。结果BG-Trap法和双层叠帐法均能够有效地捕获白纹伊蚊的雌蚊,双层叠账法捕获的白纹伊蚊占比高于BG-Trap法(χ^(2)=16.034,P<0.01),两种方法捕获的白纹伊蚊雌蚊构成比之间差异无统计学意义(χ^(2)=0.162,P=0.687)。BG-Trap法捕获的白纹伊蚊平均密度指数为7.85±5.23只/(台·h),低于双层叠帐法的27.04±13.86只/(顶·h),差异有统计学意义(t=6.73,P<0.001)。结论BG-Trap法对登革热媒介白纹伊蚊监测效果不及双层叠帐法,其能否应用于登革热媒介伊蚊监测有待于进一步研究。 展开更多
关键词 BG-trap 双层叠帐法 白纹伊蚊 监测
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BG-Trap法在伊蚊成蚊监测中的应用研究
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作者 段丽琼 黄谊 +2 位作者 姚松银 龙浩宇 戴携 《中华卫生杀虫药械》 CAS 2024年第2期139-141,共3页
目的采用BG-Trap法进行伊蚊监测,探讨该方法应用于登革热蚊媒常规监测和应急监测的可行性。方法在伊蚊监测场所用BG-Trap法分时段进行监测,用非参数统计分析的Chi-Square过程和t检验对监测结果进行统计和分析。结果应用BG-Trap法对伊蚊... 目的采用BG-Trap法进行伊蚊监测,探讨该方法应用于登革热蚊媒常规监测和应急监测的可行性。方法在伊蚊监测场所用BG-Trap法分时段进行监测,用非参数统计分析的Chi-Square过程和t检验对监测结果进行统计和分析。结果应用BG-Trap法对伊蚊进行监测,15:00—17:00监测效果明显高于9:00—11:00(雌:χ^(2)=18963,df=1,P<0001;雄:χ^(2)=18667,df=1,P<0001;总体:χ^(2)=37500,df=1,P<0001);从12:00开始,按每小时一段统计诱蚊效果,以15:00—19:00时段对伊蚊引诱效果最好,平均捕蚊量为(618±21)只/h,平均小时诱蚊量与12:00—15:00有极显著的差异(雌:t=275,df=146,P<0001;雄:t=678,df=156,P<0001;总体:t=1016,df=304,P<0001)。结论可将BG-Trap法引入伊蚊的常规监测和应急监测。 展开更多
关键词 BG-trap 白纹伊蚊 常规监测 应急监测
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基于UPLC-Q-TRAP-MS分析养心安神药对酸枣仁-五味子配伍煎煮前后10个指标成分含量变化
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作者 吴溪 许杨 +3 位作者 吴德玲 赵想 汪孰敏 高家荣 《中华中医药学刊》 CAS 北大核心 2024年第5期190-195,共6页
目的分析养心安神药对酸枣仁-五味子配伍煎煮前后主要指标成分差异变化,并建立含量测定方法。方法采用Welch Ultimate XB-C_(18)色谱柱(2.1 mm×50 mm,5μm),以0.1%甲酸水溶液(A)-乙腈(B)为流动相,流速0.4 mL/min柱温40℃,梯度洗脱... 目的分析养心安神药对酸枣仁-五味子配伍煎煮前后主要指标成分差异变化,并建立含量测定方法。方法采用Welch Ultimate XB-C_(18)色谱柱(2.1 mm×50 mm,5μm),以0.1%甲酸水溶液(A)-乙腈(B)为流动相,流速0.4 mL/min柱温40℃,梯度洗脱;质谱采用电喷雾离子源(ESI),多反应监测离子扫描模式(MRM)。分别对该药对单煎液、单煎合并液与合煎液中主要指标成分酸枣仁皂苷A、斯皮诺素、五味子醇甲、五味子酯甲、五味子甲素、五味子乙素、芦丁、槲皮素、山柰酚、山柰酚-3-O-云香糖苷进行含量测定,并分析药对配伍前后主要指标成分的含量变化差异。结果以上10种成分在一定浓度范围内均呈现良好的线性关系;精密度、重复性和稳定性RSD均良好;平均加样回收率在95.0%~102.1%,RSD为0.03%~3.7%。本次实验结果与前期试验认为酸枣仁与五味子在合煎后,主要指标成分降低保持一致性。结论多指标成分同时测定为该药对配伍质量全面控制提供新的方法并为其药效物质基础的深入研究提供依据。 展开更多
关键词 酸枣仁-五味子药对 UPLC-Q-trap-MS 含量测定
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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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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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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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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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Long-Lifetime Optical Trapping of a ^(40)Ca^(+) Ion
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作者 Zheng Chen Miao Wang +6 位作者 Baolin Zhang Huaqing Zhang Zixiao Ma Ruming Hu Yao Huang Kelin Gao Hua Guan 《Chinese Physics Letters》 SCIE EI CAS CSCD 2024年第11期45-52,共8页
We have experimentally achieved the all-optical trapping of a ^(40)Ca^(+)ion.An optical dipole trap was established using a high-power,far-detuned,tightly focused laser with a wavelength of 532 nm.The single ^(40)Ca^(... We have experimentally achieved the all-optical trapping of a ^(40)Ca^(+)ion.An optical dipole trap was established using a high-power,far-detuned,tightly focused laser with a wavelength of 532 nm.The single ^(40)Ca^(+)ion was trapped without any RF fields and demonstrated a long lifetime of over 3 s.In this experiment,we implemented several measures to improve the optical trapping probability,including focusing the dipole beam waist near the diffraction limit,precisely compensating for stray electric fields,and mitigating electron shelving in metastable states.The optical trapping of a ^(40)Ca^(+)ion eliminates the influence of micromotion induced by RF fields,potentially paving the way for development of all-optical trapping ion optical clocks. 展开更多
关键词 trapPING DIPOLE eliminate
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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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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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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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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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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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Crossroads:Pathogenic role and therapeutic targets of neutrophil extracellular traps in rheumatoid arthritis
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作者 YANG LI JIAN LIU +3 位作者 YUEDI HU CHENGZHI CONG YIMING CHEN QIAO ZHOU 《BIOCELL》 SCIE 2024年第1期9-19,共11页
Rheumatoid arthritis(RA)is a prevalent autoimmune disease whose main features include chronic synovial inflammation,bone destruction,and joint degeneration.Neutrophils are often considered to be the first responders t... Rheumatoid arthritis(RA)is a prevalent autoimmune disease whose main features include chronic synovial inflammation,bone destruction,and joint degeneration.Neutrophils are often considered to be the first responders to inflammation and are a key presence in the inflammatory milieu of RA.Neutrophil extracellular traps(NETs),a meshwork of DNA-histone complexes and proteins released by activated neutrophils,are widely involved in the pathophysiology of autoimmune diseases,especially RA,in addition to playing a key role in the neutrophil innate immune response.NETs have been found to be an important source of citrullinated autoantigen antibodies and inflammatory factor release,which can activate RA synovial fibroblasts(FLS)and cause joint damage.This article reviews the role of NETs in the pathophysiology of RA,demonstrating the application of multiple molecules with various therapies,with a view to informing the discovery and development of novel biomarkers and therapeutic targets for RA. 展开更多
关键词 Rheumatoid arthritis Neutrophil extracellular traps REVIEW
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Hydrophobic CHA-ZIFs with a junctional trap between cha and d6r cages for adsorption of 2,3-butanediol in aqueous solution
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作者 Lifang Ge Meizhen Gao +3 位作者 Xiaosheng Zhang Jiang Wang Qi Shi Jinxiang Dong 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2024年第9期90-100,共11页
The adsorption and separation of diols from dilute aqueous solution using hydrophobic materials is very challenging due to the strong diolewater hydrogen-bonding interactions.Herein,we screened hydrophobic zeolitic im... The adsorption and separation of diols from dilute aqueous solution using hydrophobic materials is very challenging due to the strong diolewater hydrogen-bonding interactions.Herein,we screened hydrophobic zeolitic imidazolate frameworks(ZIFs)with chabazite(CHA)topology for separation of 2,3-butanediol(2,3-BDO)and 1,3-propanediol(1,3-PDO),which had junctional and hydrophobic traps matching the two end methyl groups of the 2,3-BDO molecule.Based on CHA-ZIFs with the same smallsized ligand 2-methylimidazole(mIm)and different large-sized ligand benzimidazole derivatives(RbIm),CHA-ZIFs with larger surface areas were obtained by the addition of excess small-sized ligand mIm in the synthesis process.We showed that all of the hydrophobic CHA-ZIFs preferentially adsorbed 2,3-BDO over 1,3-PDO by static batch adsorption and dynamic column adsorption experiments.But ZIF-301 and ZIF-300 with halogen groups exhibited better adsorptive separation performance for 2,3-BDO/1,3-PDO than ZIF-302 with methyl groups.For a typical ZIF-301,its adsorption capacity for 2,3-BDO was 116.4 mg$g1 and selectivity for 2,3-BDO/1,3-PDO was 3.8 in dynamic column adsorption of the binarycomponent system(2,3-BDO/1,3-PDO:50 g·L^(-1)/50 g·L^(-1)).Computational simulations revealed that 2,3-BDO preferentially adsorbed in a trap at the junction between the cha and d6r cages of CHA-ZIFs,meaning the strong hosteguest interactions.Therefore,the hydrophobic CHA-ZIFs with a junctional trap were promising candidate materials for adsorbing 2,3-BDO,which also provided a new perspective for separating diols in dilute aqueous solutions. 展开更多
关键词 Adsorption Separation Aqueous solution Zeolitic imidazolate frameworks Junctional and hydrophobic trap DIOLS
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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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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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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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Optimal preparation of Bose and Fermi atomic gas mixtures of ^(87)Rb and ^(40)K in a crossed optical dipole trap
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作者 丁培波 单标 +5 位作者 赵宇航 杨雅婧 陈良超 孟增明 王鹏军 黄良辉 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第6期356-361,共6页
We report on the optimal production of the Bose and Fermi mixtures with ^(87) Rb and ^(40)K in a crossed optical dipole trap(ODT).We measure the atomic number and lifetime of the mixtures in combination of the spin st... We report on the optimal production of the Bose and Fermi mixtures with ^(87) Rb and ^(40)K in a crossed optical dipole trap(ODT).We measure the atomic number and lifetime of the mixtures in combination of the spin state |F=9/2,m_(F)=9/2> of^(40)K and |1,1>of ^(87) Rb in the ODT,which is larger and longer compared with the combination of the spin state |9/2,9/2> of^(40)K and 12,2) of ^(87)Rb in the ODT.We observe the atomic numbers of ^(87)Rb and ^(40)K shown in each stage of the sympathetic cooling process while gradually reducing the depth of the optical trap.By optimizing the relative loading time of atomic mixtures in the MOT,we obtain the large atomic number of ^(40)K(~6 ×10^(6)) or the mixtures of atoms with an equal number(~1.6 × 10^(6)) at the end of evaporative cooling in the ODT.We experimentally investigate the evaporative cooling in an enlarged volume of the ODT via adding a third laser beam to the crossed ODT and found that more atoms(8 × 10^(6)) and higher degeneracy(T/T_(F)=0.25) of Fermi gases are obtained.The ultracold atomic gas mixtures pave the way to explore phenomena such as few-body collisions and the Bose-Fermi Hubbard model,as well as for creating ground-state molecules of ^(87)Rb^(40)K. 展开更多
关键词 optical dipole trap Bose and Fermi gas mixtures atomic lifetime
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