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Phase Synchronization of Coupled Rossler Oscillators： Amplitude Effect

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Communications in Theoretical Physics 2007年第2期47卷 265-269页

作者： LI Xiao-Wen ZHENG zhi-gang Department of Physics and the Beijing-Hong-kong-Singapore Joint Center for Nonlinear and Complex Systems （Beijing） Beijing Normal University Beijing 100875 China

Phase synchronization of two linearly coupled Rossler oscillators with parameter misfits is explored. It is found that depending on parameter mismatches, the synchronization of phases exhibits different manners. The synchronization regime can be divided into three regimes. For small mismatches, the amplitude-insensitive regime gives the phase-dominant synchronization; When the parameter misfit increases, the amplitudes and phases of oscillators are correlated） and the amplitudes will dominate the synchronous dynamics for very large mismatches. The lag time among phases exhibits a power law when phase synchronization is achieved.

关键词： phase synchronization amplitude eiiect

Selective oxidation of methane and carbon deposition over Fe_2O_3/Ce_(1-x)Zr_xO_2 oxides

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Rare Metals 2014年第2期33卷 230-238页

作者： Xiu-Li Sang kong-Zhai Li Hua Wang Yong-gang Wei Quality Development Institute Kunming University of Science and Technology Engineering Research Center of Metallurgical Energy Conservation and Emission Reduction Ministry of EducationKunming University of Science and Technology

A series of Fe2O3/Al2O3, Fe2O3/CeO2, Ce0.7Zr0.3O2, and Fe2O3/Ce1-xZrxO2（x = 0.1–0.4） oxides was prepared and their physicochemical features were investigated by X-ray diffraction（XRD）, transmission electron microscope（TEM）, and H2-temperature-programmed reduction（H2-TPR） techniques. The gas–solid reactions between these oxides and methane for syngas generation as well as the catalytic performance for selective oxidation of carbon deposition in O2-enriched atmosphere were investigated in detail. The results show that the samples with the presence of Fe2O3show much higher activity for methane oxidation compared with the Ce0.7Zr0.3O2solid solution,while the CeO2-contained samples represent higher CO selectively in methane oxidation than the Fe2O3/Al2O3sample. This suggests that the iron species should be the active sites for methane activation, and the cerium oxides provide the oxygen source for the selective oxidation of the activated methane to syngas during the reaction between methane and Fe2O3/Ce0.7Zr0.3O2. For the oxidation process of the carbon deposition, the CeO2-containing samples show much higher CO selectivity than the Fe2O3/Al2O3sample, which indicates that the cerium species should play a very important role in catalyzing the carbon selective oxidation to CO. The presence of the Ce–Zr–O solid solution could induce the growth direction of the carbonfilament, resulting in a loose contact between the carbon filament and the catalyst. This results in abundant exposed active sites for catalyzing carbon oxidation, strongly improving the oxidation rate of the carbon deposition over this sample. In addition, the Fe2O3/Ce0.7Zr0.3O2also represents much higher selectivity（ca. 97 %） for the conversion of carbon to CO than the Fe2O3/CeO2sample, which can be attributed to the higher concentration of reduced cerium sites on this sample. The increase of the Zr content in the Fe2O3/Ce1-xZrxO2samples could improve the reactivity of the materials for methane oxidation, but

关键词： Methane Carbon deposition Gas–solid reaction Selective oxidation of carbon Fe2O3/Ce1-xZrxO2 catalysts

Real-time drogue recognition and 3D locating for UAV autonomous aerial refueling based on monocular machine vision

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Chinese Journal of Aeronautics 2015年第6期28卷 1667-1675页

作者： Wang Xufeng kong Xingwei zhi Jianhui Chen Yong Dong Xinmin School of Aeronautics and Astronautics Engineering Air Force Engineering University State Key Laboratory of Intelligent Technology and Systems Tsinghua University

Drogue recognition and 3D locating is a key problem during the docking phase of the autonomous aerial refueling （AAR）. To solve this problem, a novel and effective method based on monocular vision is presented in this paper. Firstly, by employing computer vision with red-ring-shape feature, a drogue detection and recognition algorithm is proposed to guarantee safety and ensure the robustness to the drogue diversity and the changes in environmental condi- tions, without using a set of infrared light emitting diodes （LEDs） on the parachute part of the dro- gue. Secondly, considering camera lens distortion, a monocular vision measurement algorithm for drogue 3D locating is designed to ensure the accuracy and real-time performance of the system, with the drogue attitude provided. Finally, experiments are conducted to demonstrate the effective- ness of the proposed method. Experimental results show the performances of the entire system in contrast with other methods, which validates that the proposed method can recognize and locate the drogue three dimensionally, rapidly and precisely.

关键词： Autonomous aerial refueling Drogue 3D locating Drogue attitudemeasurement Drogue detection Drogue recognition Monocular machine vision

Adult duodenal intussusception with horizontal adenoma: A rare case report

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World Journal of Clinical Cases 2020年第15期8卷 3314-3319页

作者： Kun-Peng Wang Hao Jiang Can kong Lie-zhi Wang Guo-Yu Wang Jing-gang Mo Chong Jin Department of General Surgery Taizhou Central Hospital(Taizhou University Hospital)Taizhou 318000Zhejiang ProvinceChina Department of Radiology Taizhou Central Hospital(Taizhou University Hospital)Taizhou 318000Zhejiang ProvinceChina

BACKGROUND Adult duodenal intussusception rarely occurs,and the majority of duodenal adenomas are located in the descending part of the ***,adenomas in the horizontal part of the duodenum presenting as duodenal intussusception in adults are extremely *** SUMMARY A 36-year-old man complained of abdominal pain for 13 *** analysis showed *** resonance cholangiopancreatography and computed tomography revealed a tumor in the horizontal part of the duodenum as the main finding,leading to duodeno-duodenal *** obvious abnormalities were found on endoscopy or upper gastrointestinal *** was diagnosed with duodenal intussusception secondary to duodenal *** showed duodeno-duodenal intussusception and a tumor in the horizontal part of the duodenum near the ascending *** pathology revealed tubular-villous adenoma with low-grade glandular intraepithelial neoplasia(local high-grade intraepithelial neoplasia).He was discharged without *** This case highlights that rational use of computed tomography,magnetic resonance cholangiopancreatography,endoscopy and upper gastrointestinal radiography for preoperative diagnosis and timely surgery is an effective strategy for the treatment of adult duodenal intussusception with duodenal masses.

关键词： Adult duodenal intussusception Duodenal adenoma Horizontal part of the duodenum Intestinal obstruction Case report

Activated pyrolysed bacterial cellulose as electrodes for supercapacitors

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Science China Chemistry 2016年第6期59卷 713-718页

作者： Xiangjun Wang Debin kong Bin Wang Yan Song Linjie zhi Key Laboratory of Carbon Materials Institute of Coal Chemistry Chinese Academy of Sciences Taiyuan 030001 China CAS Key Laboratory of Nanosystem and Hierarchical Fabrication CAS Center for Excellence in Nanoscience National Center for Nanoscience and Technology Beijing 100190 China University of Chinese Academy of Sciences Beijing 100049 China

In this paper, the bacterial celluloses(BCs) were pyrolysed in nitrogen and then activated by KOH to form a porous three- dimension-network electrode material for supercapacitor applications. Activated pyrolysed bacterial cellulose(APBC) samples with enlarged specific surface area and enhanced specific capacitances were obtained. In order to optimize electrochemical properties, APBC samples with different alkali-to-carbon ratios of 1, 2 and 3 were tested in two electrodes symmetrical capacitors. The optimized APBC sample holds the highest specific capacitance of 241.8 F/g, and the energy density of which is 5 times higher than that of PBC even at a current density of 5 A/g. This work presents a successful practice of preparing electrode material from environment-friendly biomass, bacterial cellulose.

关键词： bacterial cellulose pyrolysis activation supercapacitor

The risk factors and threshold level of subchronic inhalation exposure of reclaimed water

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Journal of Environmental Sciences 2024年第3期137卷 639-650页

作者： Jiayang kong Yun Lu Yunru Ren Menghao Chen gang Liu Liangliang Shi State Key Joint Laboratory of Environment Simulation and Pollution Control State Environment Protection Key Laboratory of Microorganism Application and Risk ControlSchool of EnvironmentTsinghua UniversityBeijing 100084China

Inhalation of reclaimed water is known to cause lung infammation,and free endotoxins have been shown to be a major risk factor for acute *** exposure has also been shown to induce infammatory responses with visible tissue ***,subchronic risk factors have yet to be identified,and a threshold for the protection of occupational populations during urban reuse is *** this study,potential risk factors in reclaimed water were examined by subchronic exposure with fractionated reclaimed water,and the health risk threshold was tested with a series of diluted reclaimed ***,following a 12-week exposure,macromolecules and microorganisms were found to be two major risk factors in reclaimed water that could cause pulmonary infammation,including increased proportion of polymorphonuclear leukocytes in bronchoalveolar fuid,formation of inducible bronchus-associated lymphoid tissue,and elevation of Immunoglobulin A ***,infammation persisted after a 4-week recovery *** calculated threshold of reclaimed water exposure for mice was 31.8 Endotoxin Unit(EU)/(kg·day)under when exposed to 50%additional relative humidity from reclaimed water at 25℃ for 2 hr/***,the subchronic threshold estimate for humans under the same exposure conditions was found to be 12.2 EU/(kg·day),corresponding to endotoxin levels of 61.7 EU/mL in reclaimed *** threshold level of endotoxin was lower than that in most non-potable reclaimed *** findings of this study suggest that occupational exposure of reclaimed water can serve as a potential risk to workers.

关键词： Reclaimed water Inhalation exposure Risk factor Threshold Infammation Endotoxin

Atomic disorders in layer structured topological insulator SnBi2Te4 nanoplates

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Nano Research 2018年第2期11卷 696-706页

作者： Yi-Chao Zou zhi-gang Chen Enze Zhang Fantai kong Yan Lu Lihua Wang John Drennan Zhongchang Wang Faxian Xiu Kyeongjae Cho Jin Zou Materials Engineering University of Queensland Brisbane Australia Centre for Future Materials University of Southern Queensland Springfield Australia Laboratory of Surface Physics and Department of Physics and Collaborative Innovation Center of Advanced Microstructures Fudan University Shanghai China Department of Materials Science & Engineering the University of Texas at Dallas Richardson USA Beijing Key Lab of Microstructure and Property of Advanced Materials Institute of Microstructure and Properties of Advanced Materials Beijing University of Technology Beijing China Centre for Microscopy and Microanalysis University of Queensland Brisbane Australia WPI Advanced Institute for Materials Research Tohoku University Sendai Japan Quantum Materials Science and Technology Department International Iberian Nanotechnology Laboratory Braga Portugal

Identification of atomic disorders and their subsequent control has proven to be a key issue in predicting, understanding, and enhancing the properties of newly emerging topological insulator materials. Here, we demonstrate direct evidence of the cation antisites in single-crystal SnBi2Te4 nanoplates grown by chemical vapor deposition, through a combination of sub-angstr6m-resolution imaging, quantitative image simulations, and density functional theory calculations. The results of these combined techniques revealed a recognizable amount of cation antisites between Bi and Sn, and energetic calculations revealed that such cation antisites have a low formation energy. The impact of the cation antisites was also investigated by electronic structure calculations together with transport measurement. The topological surface properties of the nanoplates were further probed by angle-dependent magnetotransport, and from the results, we observed a two-dimensional weak antilocalization effect associated with surface carriers. Our approach provides a pathway to identify the antisite defects in ternary chalcogenides and the application potential of SnBi2Te4 nanostructures in next-generation electronic and spintronic devices.

关键词： metal chalcogenide antisite defect nanoplate scanning transmissionelectron microscop3~magnetotransport

Cobalt and manganese stress in the microalga Pavlova viridis (Prymnesiophyceae):Effects on lipid peroxidation and antioxidant enzymes

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Journal of Environmental Sciences 2007年第11期19卷 1330-1335页

作者： LI Mei ZHU Qin HU Chang-wei CHEN Li LIU zhi-li kong zhi-ming National Key Laboratory of Pollution Control and Resource Reuse of China School of the Environment Nanjing University Nanjing 210093 China School of Life Science Nanjing University Nanjing 210093 China

Pollution of marine environment has become an issue of major concern in recent years. Serious environmental pollution by heavy metals results from their increasing utilization in industrial processes and because most heavy metals are transported into the marine environment and accumulated without decomposition. The aim of the present study is to investigate the effects on growth, pigments, lipid peroxidation, and some antioxidant enzyme activities of marine microalga Pavlova viridis, in response to elevated concentrations of cobalt （Co） and manganese （Mn）, especially with regard to the involvement of antioxidative defences against heavy metal-induced oxidative stress. In response to Co^2＋, lipid peroxidation was enhanced compared to the control, as an indication of the oxidative damage caused by metal concentration assayed in the microalgal cells but not Mn^2＋. Exposure of Pavlova viridis to the two metals caused changes in enzyme activities in a different manner, depending on the metal assayed： after Co^2＋ treatments, total superoxide dismutase （SOD） activity was irregular, although it was not significantly affected by Mn^2＋ exposure. Co^2＋ and Mn^2＋ stimulated the activities of catalase （CAT） and glutathione （GSH）, whereas, glutathione peroxidase （GPX） showed a remarkable increase in activity in response to Co^2＋ treatments and decreased gradually with Mn^2＋ concentration, up to 50 μmol/L, and then rose very rapidly, reaching to about 38.98% at 200 μmol/L Mn^2＋. These results suggest that an activation of some antioxidant enzymes was enhanced, to counteract the oxidative stress induced by the two metals at higher concentration.

关键词： antioxidant enzymes cobalt manganese malondialdehyde (MDA) Pavlova viridis

The north-south asymmetry of solar filaments separately at low and high latitudes in solar cycle 23

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Research in Astronomy and Astrophysics 2015年第1期15卷 77-84页

作者： De-Fang kong zhi-Ning Qu Qiao-Ling Guo Yunnan Observatories Chinese Academy of Sciences University of Chinese Academy of Sciences Key Laboratory of Solar Activity National Astronomical Observatories Chinese Academy of Sciences College of Mathematics Physics and Information Engineering Jiaxing University

We present the results of a study on the north-south asymmetry of solar filaments at low（〈50°） and high（〉60°） latitudes using daily filament numbers from January 1998 to November 2008（solar cycle 23）. It is found that the northern hemisphere is dominant at low latitudes for cycle 23. However, a similar asymmetry does not occur for solar filaments at high latitudes. The present study indicates that the hemispheric asymmetry of solar filaments at high latitudes in a cycle appears to have little connection with that at low latitudes. Our results support that the observed magnetic fields at high latitudes include two components： one comes from the emergence of the magnetic fields from the solar interior and the other comes from the drift of the magnetic activity at low latitudes.

关键词： Sun: activity Sun: filaments,prominences methods: data analysis