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Adhesives to empower a manipulator inspired by the chameleon tongue

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Chinese Chemical Letters 2020年第3期31卷 821-825页

作者： Chen Wang Liju Xu yan qiao Dong Qiu Beijing National Laboratory for Molecular Sciences(BNLMS) State Key Laboratory of Polymer Physics and ChemistryCAS Research/Education Center for Excellence in Molecular SciencesInstitute of ChemistryChinese Academy of SciencesBeijing 100190China University of Chinese Academy of Sciences Beijing 100190China

Existing grasping technologies have persistent challenges with unstructured objects and environments,highlighting an increasing demand for methods that conform to various application *** by the chameleon tongue,a soft-contact grasping manipulator empowered by a class of adhesive gels has been *** adhesives enable the manipulator to rapidly and strongly adhere to diverse substrates with varied surfaces,shapes and sizes,also to release objects under mild *** robustness of such adhesive gels was highlighted with the remarkable recyclability,broad temperature tolerance and long-term ***,a general approach was developed to reconcile the contradiction of simultaneously enhancing their interfacial adhesion and cohesion strength that exists in conventional *** anticipate that this work will offer a strategy of developing adhesive materials and pave the way towards new applications of soft materials in the emerging fields of soft robotic devices and smart manufacturing.

关键词： Polymer Adhesive gels Switchable adhesion Bio-inspired Manipulator

Efficacy of comprehensive remote ischemic conditioning in elderly patients with acute ST-segment elevation myocardial infarction underwent primary percutaneous coronary intervention

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Journal of Geriatric Cardiology 2022年第6期19卷 435-444页

作者： yan-Ling WANG Qi yanG Cheng-yan HU yan-yan CHU Zheng SUN huan ZHAO Zhi LIU Department of Cardiology Xuanwu HospitalCapital Medical UniversityBeijingChina Department of Radiology Chaoyang HospitalCapital Medical UniversityBeijingChina Department of Radiology Xuanwu HospitalCapital Medical UniversityBeijingChina

BACKGROUND Remote ischemic conditioning(RIC)is used to protect against myocardial ***,there is no adequate evidence for comprehensive RIC in elderly patients with ST-segment elevation myocardial infarction(STEMI).This study aimed to test whether comprehensive RIC,started pre-primary percutaneous coronary intervention(PPCI)and repeated daily on 1-30 days post-PPCI,can improve myocardial salvage index(SI),left ventricular ejection fraction(LVEF),Kansas City Cardiomyopathy Questionnaire Clinical Summary Score(KCCQ-CSS)and 6-min walk test distance(6MWD)in elderly patients with acute STEMI during 12 months *** 328 consenting elderly patients were randomized to receive standard PPCI plus comprehensive RIC(the treatment group)or standard PPCI(the control group).SI at 5-7 days after PPCI,LVEF,left ventricular end-diastolic volume index(LVEDVI),left ventricular end-systolic volume index(LVESVI),KCCQ-CSS,6MWD and adverse events rates were measured and *** SI was significantly higher in the treatment group[interquartile range(IQR):0.38-0.66,P=0.037].There were no significant differences in major adverse events at 12 *** the differences of LVEDVI,LVESVI and LVEF between the treatment group and the control group did not reach statistical significance at 6 months and 12 months,LVEF tended to be higher,LVEDVI tended to be lower in the treatment *** KCCQ-CSS was significantly higher in the treatment group at 1 month(IQR:46.5-87,P=0.001)and 12 months(IQR:55-93,P=0.008).There was significant difference in 6MWD between the treatment group and the control group(IQR:258-360 ***:250-345,P=0.002)at 1 month and(IQR:360-445 ***:345-432,P=0.035)at 12 months.A modest correlation was found between SI and LVEF(r=0.452,P<0.01),KCCQ-CSS(r=0.440,P<0.01)and 6MWD(r=0.384,P<0.01)respectively at 12 *** The comprehensive RIC can improve SI,KCCQ-CSS and *** may be an adjunctive therapy to PPCI in elderly patients with STEMI

关键词： patients infarction coronary

Effect of the head cavity on pressure oscillation suppression characteristics in large solid rocket motors

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Science China(Technological Sciences) 2015年第7期58卷 1250-1262页

作者： ZHANG qiao WANG NingFei LI JunWei SU WanXing ZHANG yan China Academy of Space Technology School of Aerospace Engineering Beijing Institute of Technology Research and Development Center China Academy of Launch Vehicle Technology Qian Xue-sen Laboratory of Space Technology

In order to discover the effect of head cavity on resonance damping characteristics in solid rocket motors, large-eddy simulations with wall-adapting-local-eddy-viscosity subgrid scale turbulent model are implemented to study the oscillation flow field induced by vortex shedding based on the VKI （yon Karman Institute） experimental motor. Firstly, mesh sensitivity analysis and grid-independent analysis are carried out for the computer code validation. Then, the numerical method is further validated by comparing the calculated results and experimental data. Thirdly, the effects of head-end cavity on the pressure oscillation am-plitudes are studied in this paper. The results indicate that cavity volume, location and configuration have a cooperative ef- fect on the oscillation amplitude. It is proved that Rayleigh criterion can be used as a guiding principle for the design of reso- nance damping cavity. The change of the head-end cavity breaks the balance between the mass flux and acoustic energy. Therefore, the pressure oscillation characteristics change accordingly. It is concluded that a large mass flux added at the pres- sure antinode could attribute to significant amplitude. Meanwhile, the damping effect of the cavity is stronger when the dis- tance between cavity and pressure antinode becomes shorter. Finally, this method is applied to the modification of an engi- neering solid rocket motor. The static test of solid rocket motor reflects that the oscillations can be effectively suppressed by a head-end cavity.

关键词： solid rocket motor combustion instability large eddy simulation rayleigh criterion suppression method

Joint DOA and polarization estimation for unequal power sources based on reconstructed noise subspace

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Journal of Systems Engineering and Electronics 2016年第3期27卷 501-513页

作者： Yong Han Qingyuan Fang Fenggang yan Ming Jin Xiaolin qiao School of Electronics and Information Engineering Harbin Institute of Technology School of Information Science and Technology Shijiazhuang Tiedao University

In most literature about joint direction of arrival（DOA） and polarization estimation, the case that sources possess different power levels is seldom discussed. However, this case exists widely in practical applications, especially in passive radar systems. In this paper, we propose a joint DOA and polarization estimation method for unequal power sources based on the reconstructed noise subspace. The invariance property of noise subspace（IPNS） to power of sources has been proved an effective method to estimate DOA of unequal power sources. We develop the IPNS method for joint DOA and polarization estimation based on a dual polarized array. Moreover, we propose an improved IPNS method based on the reconstructed noise subspace, which has higher resolution probability than the IPNS method. It is theoretically proved that the IPNS to power of sources is still valid when the eigenvalues of the noise subspace are changed artificially. Simulation results show that the resolution probability of the proposed method is enhanced compared with the methods based on the IPNS and the polarimetric multiple signal classification（MUSIC） method. Meanwhile, the proposed method has approximately the same estimation accuracy as the IPNS method for the weak source.

关键词： invariance property of noise subspace(IPNS) joint DOA and polarization estimation multiple signal classification(MUSIC) reconstruction of noise subspace unequal power sources

Judd-Ofelt Analysis on Trifluoroacetate Europium Complexes for Liquid Laser Media

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Chemical Research in Chinese Universities 2013年第1期29卷 166-170页

作者： SHE Jiang-bo LI Dong-dong GAO Fei qiao Ze-bang LIU huan-huan WEI Wei PENG Bo State Key Laboratory of Transient Optics and Photonics Xi 'an Institute of Optics and Precision Mechanics Chinese Academy of Science Xi 'an 710119 P. R. China School of Electronic Engineering Xi' an University of Posts and Telecommunications Xi 'an 710121 P. R. China Institute of Advanced Materials Nanjing University of Posts and Telecommunications Nanjing 210003 P. R. China

Four europium trifiuoroacetate complexes, Eu（CF3COO）3＂bpy（bpy=2,2＇-bipyridine）（l）, Eu（CF3COO）3＂ phen（phen=l,10-phenanthroline）（2）, Eu（CF3COO）3.2bp（bp=benzophenone）（3） and Eu（CF3COO）3-2tppo（tppo=triphenyl- phosphine oxide）（4） were synthesized and characterized by elemental analysis, Fourier transform infrared（FTIR） spectroscopy, photoluminescence（PL） spectroscopy and thermogravimetric analysis（TGA）. The PL spectra of the complexes at room temperature show the strong typical Eu3＋ ion red emission, due to the efficient energy ＂antenna absorption＂ of ligands and transitions of Eu3＋ ion between 5Do----7Fj（j-0-4）. The long lifetime and high quantum yield reflect that the multiphonon relaxations by coupling to O--H and C--H vibrations were reduced. According to the photoluminescent spectra, the Judd-Ofelt parameters f22 and 04 of the complexes were calculated and the radiative properties were also presented. The 5D0 radiative lifetime, quantum yield and the stimulated emission cross-section of the complexes are excellent, which prove that they have promising optical properties for liquid laser. The thermal analyses indicate that they are quite stable to heat.

关键词： Europium complex Luminescent property Judd-Ofelt theory

Unfavorable environmental conditions for tropical cyclone genesis over the western North Pacific during the Last Interglacial based on PMIP4 simulations

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Atmospheric and Oceanic Science Letters 2023年第5期16卷 68-74页

作者： Dubin huan Qing yan Ting Wei Nansen-Zhu International Research Centre Institute of Atmospheric PhysicsChinese Academy of SciencesBeijingChina Key Laboratory of Meteorological Disaste//Collaborative Innovation Center on Forecast and Evaluation of Meteorological Disasters Nanjing Unversity of Information Science and TechnologyNanjing China State Key Laboratory of Severe Weather Chinese Academy of Meteorological SciencesBeijing China Undversty of Chinse Acadenry of Scdences Beljing Chuna

研究过去暖期西北太平洋热带气旋的变化有助于理解未来气候变暖情景下热带气旋的可能变化.本研究基于PMIP4多模式输出结果,分析了末次间冰期西北太平洋热带气旋大尺度生成因子的变化及相关机制.结果表明,末次间冰期西北太平洋风暴季潜... 详细信息

研究过去暖期西北太平洋热带气旋的变化有助于理解未来气候变暖情景下热带气旋的可能变化.本研究基于PMIP4多模式输出结果,分析了末次间冰期西北太平洋热带气旋大尺度生成因子的变化及相关机制.结果表明,末次间冰期西北太平洋风暴季潜在强度降低,湿熵亏损升高,绝对涡度减弱,中部垂直风切变增强,西南部减弱.进一步,基于生成潜势指数,指出末次间冰期西北太平洋生成潜势降低,这表明环境条件不利于热带气旋生成。

关键词：热带气旋末次间冰期 PMIP4

Contributions of optimized tensor interactions on the binding energies of nuclei

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Nuclear Science and Techniques 2020年第2期31卷 11-19页

作者： Di Wu Chun-Lin Bai H.Sagawa Zeng-Qiang Song huan-qiao Zhang College of Physics Sichuan UniversityChengdu 610065China RIKEN Nishina Center Wako 351-0198Japan Center for Mathematics and Physics University of AizuAizu-WakamatsuFukushima 965-8560Japan China Institute of Atomic Energy Beijing 102413China

The tensor parts of Skyrme interactions are constrained from the collective charge-exchange spin-dipole and Gamow-Teller excitation energies in 90Zr and 208Pb,together with the isotopic dependence of energy splitting between proton h11=2 and g7=2 single-particle orbits along the Z=50 *** the optimized tensor interactions,the binding energies of spherical or weakly deformed nuclei with A=54-228 are studied *** present results show that the global effect of tensor interaction is attractive and systematically increases the binding energies of all these nuclei and makes the nuclei more *** root mean squared deviation of the calculated binding energies from the experimental values is significantly improved by the optimized tensor interactions,and the contribution of the tensor interaction to the binding energy is estimated.

关键词： Tensor force Binding energy Gamow-Teller transition Spin-dipole transition Single-particle energy differences

Direct Quantitative Determination of Rare Earth Elements in REE-rich Mineral Powders by LA-ICP-MS

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Chemical Research in Chinese Universities 2017年第3期33卷 360-364页

作者： KE Yuqiu GUO Wei JIN Lanlan qiao Lei yanG huan HU Shenghong State Key Laboratory of Biogeology and Environmental Geology School of Earth Sciences China University of Geoscienees Wuhan 430074 P. R. China

For direct quantitative determination of rare earth elements（REE） in REE-rich minerals, a most acceptable reference material NIST 610 might be an alternative external calibration standard due to the lack of matrix-matched reference materials. Here, we aimed to develop an analytical method for direct quantitative determination of REE concentrations in REE-rich minerals via laser ablation-inductively coupled plasma-mass spectrometry（LA-ICP-MS）. The results show that the REE concentrations measured via LA-ICP-MS using NIST 610 as an extemal standard are in good agreement with reference values with relative percentage difference（Dr） mainly less than 15%. Overall, these results demonstrate that our proposed analytical method is robust and accurate for direct quantitative determination of REE concentrations in REE-rich minerals.

关键词： Laser ablation-inductively coupled plasma-mass spectxometry(LA-ICP-MS) Rare earth element(REE) REE-rich mineral NIST 610

The present and future of whole-exome sequencing in studying andtreating human reproductive disorders

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Journal of Genetics and Genomics 2018年第10期45卷 517-525页

作者： Wei Guo Xiaohui Zhu Liying yan Jie qiao Center for Reproductive Medicine Department of Obstetrics and Gynecology Peking University Third Hospital Beijing 100191 China Key Laboratory of Assisted Reproduction Ministry of Education Beijing 100191 China Beijing Key Laboratory of Reproductive Endocrinology and Assisted Reproduction Beijing 100191 China Beijing Advanced Innovation Center for Cenomics (ICG) Peking University Beijing 100871 China Peking-Tsinghua Center for Life Sciences Peking University Beijing 100871 china

The causes of recurrent spontaneous abortion (RSA) and fetal malformations are multifactorial and unclear in most cases. Environmental, maternal, and genetic factors have been shown to contribute to these defects. Whole-exome sequencing (WES) is widely used to detect genetic variations associated with human diseases and has recently been successfully applied to unveil genetic causes of unexplained recurrent spontaneous abortion (URSA) and fetal malformations. Here, we review the current discovery and diagnosis strategies to identify the underlying pathogenic mutations of URSA and fetal malformations using WES technology and propose to further develop WES, both to advance our understanding of these diseases and to eventually lead to targeted therapies for reproductive disorders.

关键词： Whole exome sequencing (WES) Unexplained recurrent spontaneous abortion (URSA) Fetal malformations Human reproduction