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Numerical analysis of motional mode coupling of sympathetically cooled two-ion crystals

Chinese Physics B 2021年第7期30卷 234-243页

作者： li-jun du Yan-Song Meng Yu-ling He jun Xie China Academy of Space Technology(Xi'an) Xi'an 710100China National Key Laboratory of Science and Technology on Space Microwave China Academy of Space Technology(Xi'an)Xi'an 710100China China Academy of Space Technology Beijing 100094China

A two-ion pair in a linear Paul trap is extensively used in the research of the simplest quantum-logic system;however,there are few quantitative and comprehensive studies on the motional mode coupling of two-ion systems *** study proposes a method to investigate the motional mode coupling of sympathetically cooled two-ion crystals by quantifying three-dimensional(3 D)secular spectra of trapped ions using molecular dynamics *** 3 D resonance peaks of the^(40)Ca^(+)–^(27)Al^(+)pair obtained by using this method were in good agreement with the 3 D in-and out-of-phase modes predicted by the mode coupling theory for two ions in equilibrium and the frequency matching errors were lower than 2%.The obtained and predicted amplitudes of these modes were also qualitatively *** was observed that the strength of the sympathetic interaction of the^(40)Ca^(+)–^(27)Al^(+)pair was primarily determined by its axial in-phase *** addition,the frequencies and amplitudes of the ion pair's resonance modes(in all dimensions)were sensitive to the relative masses of the ion pair,and a decrease in the mass mismatch enhanced the sympathetic cooling *** sympathetic interactions of the^(40)Ca^(+)–^(27)Al^(+)pair were slightly weaker than those of the^(24)Mg^(+)–^(27)Al^(+)pair,but significantly stronger than those of^(9)Be^(+)–^(27)Al^(+).However,the Doppler cooling limit temperature of^(40)Ca^(+)is comparable to that of^(9)Be^(+)but lower than approximately half of that of^(24)Mg^(+).Furthermore,laser cooling systems for^(40)Ca^(+)are more reliable than those for^(24)Mg^(+)and^(9)Be^(+).Therefore,^(40)Ca^(+)is probably the best laser-cooled ion for sympathetic cooling and quantum-logic operations of^(27)Al^(+)and has particularly more notable comprehensive advantages in the development of high reliability,compact,and transportable^(27)Al^(+)optical *** methodology may be extended to multi-ion systems,and it will greatly aid efforts to control the dy

关键词： sympathetic cooling coupled oscillations secular motion radio-frequency ion traps

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Investigation of the Ce-Mn conversion coating on 6063 aluminium alloy

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Chinese Science Bulletin 2010年第29期55卷 3345-3349页

作者： ZHANG junjun li WenFang du jun HAN Dong ZHENG XiaoPing School of Materials Science and Engineering South China University of Technology Guangzhou 510640 China

In this paper,the sustainable Ce-Mn chemical conversion coating was fabricated on 6063 aluminium alloy by means of Ce(NO3)3 and KMnO4 as the inhibitors and NaF as the *** morphologies,composition and valence state of the coating were analyzed by scanning electron microscopy(SEM),energy dispersive spectrometry(EDS) and X-ray photoelectron spectroscopy(XPS),*** results indicated that the Ce-Mn conversion coating was *** anticorrosion of the coating was evaluated in 3.5 wt.% NaCl aqueous solution at room temperature by using polarization curve and electrochemical impedance spectroscopy(EIS).It indicated that the treated surface presented better anticorrosion behavior in chloride media than on the original material *** corrosion resistance of Ce-Mn conversion coating was about equal to the trivalent chromium conversion coating.

关键词： 6063铝合金高锰酸钾转化膜扫描电子显微镜耐腐蚀性能行政电化学阻抗谱氯化钠水溶液

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Helicobacter pylori eradication therapy for functional dyspepsia: Systematic review and meta-analysis

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World Journal of Gastroenterology 2016年第12期22卷 3486-3495页

作者： li-jun du Bin-Rui Chen John J Kim Sarah Kim Jin-Hua Shen Ning Dai Department of Gastroenterology Sir Run Run Shaw Hospital Zhejiang University Hangzhou 310020 Zhejiang Province China Division of Gastroenterology Loma Linda University Loma Linda CA 92354 United States

AIM: To evaluate whether Helicobacter pylori (H. pylori) eradication therapy benefits patients with functional dyspepsia (FD).METHODS: Randomized controlled trials (RCTs) investigating the efficacy and safety of H. pylori eradication therapy for patients with functional dyspepsia published in English (up to May 2015) were identified by searching PubMed, EMBASE, and The Cochrane library. Pooled estimates were measured using the fixed or random effect model. Overall effect was expressed as a pooled risk ratio (RR) or a standard mean difference (SMD). All data were analyzed with Review Manager 5.3 and Stata ***: This systematic review included 25 RCTs with a total of 5555 patients with FD. Twenty-three of these studies were used to evaluate the benefits of H. pylori eradication therapy for symptom improvement; the pooled RR was 1.23 (95%CI: 1.12-1.36, P during long-term follow-up at ≥ 1 year (RR = 1.24; 95%CI: 1.12-1.37, P during short-term follow-up at lity of life with an SMD of -0.01 (95%CI: -0.11 to 0.08, P = 0.80). Six studies demonstrated that H. pylori eradication therapy reduced the development of peptic ulcer disease compared to no eradication therapy (RR = 0.35; 95%CI: 0.18-0.68, P = 0.002). Eight studies showed that H. pylori eradication therapy increased the likelihood of treatment-related side effects compared to no eradication therapy (RR = 2.02; 95%CI: 1.12-3.65, P = 0.02). Ten studies demonstrated that patients who received H. pylori eradication therapy were more likely to obtain histologic resolution of chronic gastritis compared to those who did not receive eradication therapy (RR = 7.13; 95%CI: 3.68-13.81, P < 0.00001).CONCLUSION: The decision to eradicate H. pylori in patients with functional

关键词： Functional dyspepsia Helicobacter pylori eradication Symptom improvement Quality of life Peptic ulceration Meta-analysis

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Targets capture by distributed active swarms via bio-inspired reinforcement learning

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Science China(Physics,Mechanics & Astronomy) 2025年第1期Mechanics & Astronomy) .卷 210-221页

作者： Kun Xu Yue li jun Sun Shuyuan du Xinpeng Di Yuguang Yang Bo li Institute of Biomechanics and Medical Engineering Applied Mechanics Laboratory Department of Engineering MechanicsTsinghua University Institute of Nuclear and New Energy Technology Tsinghua University Shanghai Aerospace Control Technology Institute Shanghai Key Laboratory of Aerospace Intelligent Control Technology College of Automation Engineering Nanjing University of Aeronautics and Astronautics

Natural swarms arranged from cells to herds are usually decentralized but display intriguing collective intelligence in coordinating individuals across large scales to efficiently achieve their common goals. Learning from nature may provide new strategies for controlling collective dynamics of synthetic swarms to accomplish specific functions. Here, we present a bioinspired computational framework that steers distributed active swarms to collectively capture and merge targets via reinforcement learning. We exploit collective milling structures of natural herds to cage the targets, and adopt a switching control policy inspired by sperms' chiral dynamics to optimize the trajectories of individuals, through which the active swarms can selforganize to enclose single or multiple distant targets in a dynamical, adaptive and scalable manner. There exists a critical swarm size, beyond which the excessive competition between agents would generate large mechanical forces, leading to capture instability but enabling the transition from short-distance to long-distance merging capture of multiple targets. This work provides physical insights into distributed active swarms and could offer a multilevel, decentralized strategy toward controlling swarm robotics in wide applications such as bio-medical devices, machine immunity, and target clearance.

关键词： swarm intelligence robotics multi-tasks artificial intelligence bionics

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Quantitative evaluation of space charge effects of laser-cooled three-dimensional ion system on a secular motion period scale

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Chinese Physics B 2018年第4期27卷 292-298页

作者： li-jun du Hong-Fang Song Shao-Long Chen Yao Huang Xin Tong Hua Guan Ke-lin Gao China Academy of Space Technology (Xi'an) Xi'an 710100 China State Key Laboratory of Magnetic Resonance and Atomic and Molecular Physics Wuhan Institute of Physics and Mathematics Chinese Academy of Sciences Wuhan 430071 China Key Laboratory of Atomic Frequency Standards Wuhan Institute of Physics and Mathematics Chinese Academy of Sciences Wuhan 430071 China Center for Cold Atom Physics Chinese Academy of Sciences Wuhan 430071 China University of Chinese Academy of Sciences Beijing 100049 China

In this paper,we introduce a method of quantitatively evaluating and controlling the space charge effect of a lasercooled three-dimensional（3 D） ion system in a linear Paul *** relationship among cooling efficiency,ion quantity,and trapping strength is analyzed quantitatively,and the dynamic space distribution and temporal evolution of the 3 D ion system on a secular motion period time scale in the cooling process are *** ion number influences the eigen-micromotion feature of the ion *** trapping parameter q is ～ 0.3,relatively ideal cooling efficiency and equilibrium temperature can be *** decrease of axial electrostatic potential is helpful in reducing the micromotion heating effect and the degradation in the total *** a single secular motion period under different cooling conditions,ions transform from the cloud state（each ion disperses throughout the envelope of the ion system） to the liquid state（each ion is concentrated at a specific location in the ion system） and then to the crystal state（each ion is subjected to a fixed motion track）.These results are conducive to long-term storage and precise control,motion effect suppression,high-efficiency cooling,and increasing the precision of spectroscopy for a 3 D ion system.

关键词： space charge effects cooling dynamics ion trajectory ion energy

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FEASIBIliTY OF DIAGNOSING AND STAGING liVER FIBROSIS WITH DIFFUSION WEIGHTED IMAGING

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Chinese Medical Sciences Journal 2008年第3期23卷 183-186页

作者： Nai-yi Zhu Ke-min Chen Wei-min Chai Wei-xia li lian-jun du Department of Radiology Ruijin Hospital School of Medicine Shanghai Jiaotong University Shanghai 200025

Objective To assess the clinical feasibility of diagnosing and staging liver fibrosis by apparent diffusion coefficient (ADC). Methods Totally, 43 patients (mean age 29.3 years) with chronic hepatitis by liver biopsy and 7 healthy controls (mean age 39.9 years) underwent liver diffusion weighted imaging (DWI) with four b values: 0, 200, 500, and 1000 s/mm2 respectively. The liver fibrosis was staged according to Ishak fibrosis stage. The ADC value of liver fibrosis patients and healthy controls was compared. The correlation of ADC value and liver fibrosis staging was analyzed. Result The histological staging showed 8 stage 1 patients, 10 stage 2 patients, 6 stage 3 patients, 9 stage 4 patients, 8 stage 5 patients and 2 stage 6 patients. The mean ADC value of liver fibrosis patients was significantly lower than that of healthy controls except for stage 1 group (P liver fibrosis staging and ADC value (r = -0.697 with b=500 s/mm2, P liver fibrosis (Ishak stage F3 and higher) showed that area under curve = 0.913, 0.825, and 0.794 with b = 500, 1000, and 200 s/mm2, respectively (95% confidence interval: 83.6%-99.0%, 70.7%-94.3%, 66.5%- 92.4%; P liver fibrosis were the highest. Conclusion DWI is proved to be a useful clinical tool in the quantitative evaluation of liver fibrosis and in the prediction of the process of liver fibrosis with the recommendable b value (500 s/mm2).

关键词： diffusion weighted imaging apparent diffusion coefficient liver fibrosis

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Investigation on the electrochemical behaviours of Mg_(2-x)Cr_xNi negative electrode

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Rare Metals 2003年第2期22卷 144-149页

作者： XUE Jianshe, WANG lijun, LUO Yuanhui, li Guoxun, du jun, HU Guangyong, and WANG ChaoqunGeneral Research Institute for Non-ferrous Metals, Beijing 100088, China (Received 2002-09-01) Generald Research Institute for Non-ferrous Metals 北京 100088

A series of Mg_(2-x)Cr_xNi alloy powder has been produced by combination ofsolid-state diffusion with mechanical grinding (MG). X-ray diffraction patterns show that the alloypowders have an amorphous structure and great increase in the specific surface. Electrochemicaldetection results indicate that the partial substitution of Mg by Cr in Mg_2Ni alloy improves thecycle life of this alloy greatly, which gets up to 100 cycles at 200 mA/g mass discharge current,keeping its mass discharge capacity over 200 mA.h/g. In the meanwhile, partial replacement of Mg byCr also increases the mass discharge capacity compared with Mg_2Ni alloy. With the increasing ofmass discharge current and content of Cr in Mg_(2-x)Cr_xNi, the cycle life of the alloys areincreased and the decay of mass discharge capacity slows down.

关键词： electrochemistry hydrogen storage alloy Ni-MH battery mechanicalgrinding Mg_2Ni

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Fructo-oligosaccharide intensifies visceral hypersensitivity and intestinal inflammation in a stress-induced irritable bowel syndrome mouse model

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World Journal of Gastroenterology 2017年第47期23卷 8321-8333页

作者： Bin-Rui Chen li-jun du Hui-Qin He John J Kim Yan Zhao Ya-Wen Zhang liang Luo Ning Dai Department of Gastroenterology Sir Run Run Shaw Hospital School of Medicine Zhejiang University Division of Gastroenterology Loma Linda University Medical Center

AIM To determine whether fructo-oligosaccharide(FOS) affects visceral sensitivity, inflammation, and production of intestinal short-chain fatty acids(SCFA) in an irritable bowel syndrome(IBS) mouse *** Mice were randomly assigned to daily oral gavage of saline solution with or without FOS(8 g/kg body weight) for 14 d. Mice were further assigned to receive either daily one-hour water avoidance stress(WAS) or sham-WAS for the first 10 d. After 2 wk, visceral sensitivity was measured by abdominal withdrawal reflex in response to colorectal distension and mucosal inflammation was evaluated. Gas chromatography, real-time reverse transcription PCR, and immunohistochemistry assays were used to quantify cecal concentrations of SCFA, intestinal cytokine expression, and number of intestinal mast cells per high-power field(HPF), *** Mice subjected to WAS exhibited visceral hypersensitivity and low-grade inflammation. Among mice subjected to WAS, FOS increased visceral hypersensitivity and led to higher cecal concentrations of acetic acid(2.49 ± 0.63 mmol/L vs 1.49 ± 0.72 mmol/L, P line administration. FOS also increased ileal interleukin(IL)-23 mR NA(4.71 ± 4.16 vs 1.00 ± 0.99, P line administration in mice subjected to WAS. No difference in visceral sensitivity, intestinal inflammation, or cecal SCFA levels was detected with or without FOS administration in mice subjected to *** FOS administration intensifies visceral hypersensitivity and gut infla

关键词： Fructo-oligosaccharide Stress Irritable bowel syndrome Visceral hypersensitivity Intestinal inflammation Short chain fatty acids FODMAP

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Targeting cholesterol trafficking to mitigate axonal degeneration in hereditary spastic paraplegia

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Neural Regeneration Research 2025年第5期20卷 1397-1398页

作者： Zhenyu Chen Xue-jun li Department of Biomedical Sciences University of Illinois College of Medicine RockfordRockfordILUSA Department of Bioengineering University of Illinois at ChicagoChicagoILUSA

Axonal degeneration underlies many debilitating diseases including hereditary spastic paraplegia(HSP),a genetically and clinically diverse group of disorders characterized by spasticity and weakness of the lower *** is one significant cause of chronic neurodisability due to the lack of effective treatments and a wide range of onset ages from early childhood to 70 years.

关键词： degeneration diseases hereditary

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Weighted Composition Operators between Bergman-Type Spaces

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Journal of Mathematical Research and Exposition 2009年第5期29卷 848-856页

作者： liU Jing Cheng ZHANG Xue jun li du Xiang College of Mathematics and Computer Science Hunan Normal University Hunan 410081 China

Let g1,g2 be normal functions. For all 0 〈 p,q 〈 ∞, the necessary and sufficient conditions for weighted composition operators Tψ,φ ： A^Pg1 → A^Pg2 to be bounded or compact between Bergman type spaces on the un... 详细信息

关键词： weighted composition operator Boundedness compactness Bergman type spaces.

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