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Anisotropic Diffusion Evolution of Vacancies Created by Oxygen Etching on a Si Surface

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Chinese Physics Letters 2011年第7期28卷 239-241页

作者： WANG Shu-Hua cai qun State Key Laboratory of Surface Physics and Department of Physics Fudan UniversityShanghai 200433 College of Sciences Shanghai Institute of TechnologyShanghai 200233

We report the diffusion behavior of dimer vacancies on a Si(100)-(2×1)surface by using ultrahigh−vacuum scanning tunneling *** dimer vacancies are created by oxygen etching of Si atoms at elevated *** annealing the sample at 600–750°C,the dimer vacancies uniformly distribute on the terrace nucleate to form larger elongated voids of one atomic layer *** long axis of these voids is parallel to the Si dimer *** annealing,the surface morphology evolves in a way dominantly caused by the anisotropic diffusion of the dimer vacancies.A difference of diffusion barriers of 0.17±0.09 eV is obtained between the[110]and[110]directions.

关键词： diffusion annealing Oxygen

Simultaneous Formation of AlB 2 -Type and ThSi 2 -Type Nanoislands of Er Silicide by Using a Prepatterned Si(001) Substrate

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Chinese Physics Letters 2013年第9期30卷 124-127页

作者： LIU Bei-Bei cai qun State Key Laboratory of Surface Physics and Department of Physics Fudan UniversityShanghai 200433

We report the simultaneous growth of hexagonal AlB 2-phase and tetragonal ThSi 2-phase nanoislands of erbium silicide on the same silicon *** a new technique,the patterned Si(001)surface with pits in a reverse-pyramid shape and{111}sidewalls is taken as the substrate *** distribution of nanoislands reveals that the upward diffusion over surface steps plays an influential role on the location of ***{111}facets on the pit sidewalls actually provide growth symmetry for the hexagonal *** work paves the way for exploring the intrinsic electrical transport properties of metal-semiconductor nanocontacts.

关键词： walls hexagonal template

Effect of Multiple Depositions and Annealing Treatments on the Erbium Silicide Nanoislands Self-Assembled on Si(001)Substrates

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Chinese Physics Letters 2012年第3期29卷 176-179页

作者： DING Tao SONG Jun-Qiang cai qun Institute of Precision Optical Engineering Department of PhysicsTongji UniversityShanghai 200092 State Key Laboratory of Surface Physics and Department of Physics Fudan UniversityShanghai 200433 CAS Key Laboratory of Materials for Energy Conversion Shanghai Institute of CeramicsChinese Academy of SciencesShanghai 200050

Erbium silicide nanoislands on Si(001)surface are fabricated by novel multiple depositions and annealing treatments *** morphological investigations determine that the islands could grow with stable square shapes rather than the shape transformation exhibited in the traditional single time evaporation *** distributions analyses further elucidate the effect of multiple depositions and annealing treatments on the nanoisland *** is suggested that strain relaxation and static coMescence play important roles in the cyclic ***,after 15 times of the cycles,the larger islands are found to undergo the Ostwald ripening,which make the shape of nanoislands *** gives us the direction to adjust the growth parameters to control the island ***,the crystalline structure of the Er silicide nanoislands is efficiently characterized by grazing incidence synchrotron x-ray diffraction.

关键词： Erbium island annealing

Usefulness of tumor traction with a snare and endoclips in gastric submucosal tumor resection:a propensity-score-matching analysis

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Gastroenterology Report 2021年第2期9卷 125-132,I0001,I0002页

作者： Qiang Zhang Jian-qun cai Zhen Wang Guangdong Provincial Key Laboratory of Gastroenterology Department of GastroenterologyNanfang HospitalSouthern Medical UniversityGuangzhouGuangdongP.R.China

Background:Endoscopic resection,including endoscopic submucosal dissection(ESD)and endoscopic full-thickness resection(EFR),was used to resect small gastric submucosal tumors(SMTs).Our team explored a method of tumor traction using a snare combined with endoclips to assist in the resection of *** study aims to explore the safety and effectiveness of the ***:This research performed a propensity-score-matching(PSM)analysis to compare ESD/EFR assisted by a snare combined with endoclips(ESD/EFR with snare traction)with conventional ESD/EFR for the resection of gastric *** were made between the two groups,including operative time,en bloc resection rate,perioperative complications,and operation-related ***:A total of 253 patients with gastric SMTs resected between January 2012 and March 2019 were included in this *** yielded 51 matched *** significant differences were identified between the two groups in perioperative complications or the costs of disposable endoscopic surgical ***,the ESD/EFR-with-snare-traction group had a shorter median operative time(39 vs 60 min,P=0.005)and lower rate of en bloc resection(88.2%vs 100%,P¼0.027).Conclusions:ESD/EFR with snare traction demonstrated a higher efficiency and en bloc resection rate for gastric SMTs,with no increases in perioperative complications and the costs of endoscopic surgical ***,the method seems an appropriate choice for the resection of gastric SMTs.

关键词： endoscopic submucosal dissection endoscopic full-thickness resection gastric submucosal tumor snare endoclip

Protective mechanisms of micro RNA-27a against oxygen-glucose deprivation-induced injuries in hippocampal neurons

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Neural Regeneration Research 2016年第8期11卷 1285-1292页

作者： qun cai Ting Wang Wen-jie Yang Xing Fen Department of Neonatology Children's Hospital of Soochow University Suzhou Jiangsu Province China Department of Emergency Affiliated Hospital of Nantong University Nantong Jiangsu Province China Medical College of Nantong University Nantong Jiangsu Province China

Hypoxic injuries during fetal distress have been shown to cause reduced expression of micro RNA-27a（mi R-27a）,which regulates sensitivity of cortical neurons to *** hypothesized that miR-27 a overexpression attenuates hypoxia- and ischemia-induced neuronal apoptosis by regulating FOXO1,an important transcription factor for regulating the oxidative stress ***-27 a mimic was transfected into hippocampal neurons to overexpress miR-27 *** showed increased hippocampal neuronal viability and decreased caspase-3 *** luciferase reporter gene system demonstrated that mi R-27 a directly binded to FOXO1 3′UTR in hippocampal neurons and inhibited FOXO1 expression,suggesting that FOXO1 was the target gene for mi R-27 *** findings confirm that mi R-27 a protects hippocampal neurons against oxygen-glucose deprivation-induced *** mechanism might be mediated by modulation of FOXO1 and apoptosis-related gene caspase-3 expression.

关键词： nerve regeneration brain injury miR-27a hypoxic-ischemic hippocampal neurons oxygen-glucose deprivation cell survival apoptosis caspase 3 FOX01 luciferase reporter gene system neuroprotection neural regeneration

Improvement of the Compressive Strength of Carbon Fiber/Epoxy Composites via Microwave Curing

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Journal of Materials Science & Technology 2016年第3期32卷 226-232页

作者： Xuehong Xu Xiaoqun Wang qun cai Xu Wang Ran Wei Shanyi Du School of Materials Science and Engineering Beihang University Shanghai Aircraft Manufacturing Co. Ltd.

Microwave processing was used to cure the carbon fiber/epoxy composites and designed for improving the compressive strength of the materials. By controlling the power of microwave heating, vacuum bagged laminates were fabricated under one atmosphere pressure without arcing. The physical and mechanical properties of composites produced through vacuum bagging using microwave and thermal curing were compared and the multistep （2-step or 3-step） microwave curing process for improved compressive properties was established. The results indicated that microwave cured samples had somewhat differentiated molecular structure and showed slightly higher glass transition temperature. The 2-step process was found to be more conducive to the enhancement of the compressive strength than the 3-step process. A 39% cure cycle time reduction and a 22% compressive strength increment were achieved for the composites manufactured with microwave radiation. The improvement in specific compressive strength was attributed to better interracial bonding between resin matrix and the fibers, which was also demonstrated via scanning electron microscopy analysis.

关键词： Carbon fiber Epoxy Microwave curing Compressive properties

Thermal Stability and Growth Behavior of Erbium Silicide Nanowires Self-Assembled on a Vicinal Si(001) Surface

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Chinese Physics Letters 2011年第6期28卷 218-221页

作者： DING Tao SONG Jun-Qiang LI Juan cai qun State Key Laboratory of Surface Physics and Department of Physics Fudan UniversityShanghai 200433 Institute of Precision Optical Engineering Department of PhysicsTongji UniversityShanghai 200092

Erbium silicide nanowires are self-assembled on vicinal Si(001)substrates after electron beam evaporation and post annealing at 630°C In−situ scanning tunneling microscopy investigations manifest that the nanowires will successively shrink and transform into a nanoisland with annealing ***,a structural transition from hexagonal AlB2 phase to tetragonal ThSi2 phase is revealed with high-resolution transmission electron *** is also found that the nanowires gradually expand to embed into the substrates during the growth process,which has much influence on the shape instability of ***,a multiple deposition-annealing treatment is given as a novel growth method to strengthen the controlled fabrication of nanowires.

关键词： nanowires annealing hexagonal

Spatiotemporal mode-locked multimode fiber laser with dissipative four-wave mixing effect

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Chinese Physics B 2022年第10期31卷 165-170页

作者： Ming-Wei Qiu Chao-qun cai Zu-Xing Zhang Advanced Photonic Technology Laboratory College of Electronic and Optical Engineering&College of MicroelectronicsNanjing University of Posts and TelecommunicationsNanjing 210023China

The high degree of freedom and novel nonlinear phenomena of multimode fiber are attracting attention. In this work,we demonstrate a spatiotemporal mode-locked multimode fiber laser, which relies on microfiber knot resonance(MKR) via dissipative four-wave-mixing(DFMW) to achieve high-repetition-rate pulses. Apart from that, DFMW mode locking with switchable central wavelengths can also be obtained. It was further found that high pulse energy induced nonlinear effect of the dominant mode-locking mechanism transforming from DFMW to nonlinear Kerr beam cleaning effect(NL-KBC). The experimental results are valuable for further comprehending the dynamic characteristics of spatiotemporal mode-locked multimode fiber lasers, facilitating them much more accessible for applications.

关键词： microfiber knot resonance(MKR) dissipative four-wave-mixing(DFMW) nonlinear Kerr beam cleaning effect(NL-KBC) multimode fiber laser

Direct one-pot synthesis of zolimidine pharmaceutical drug and imidazo [1,2-a] pyridine derivatives via I_2/CuO-promoted tandem strategy

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Chinese Chemical Letters 2015年第7期26卷 881-884页

作者： qun cai Mei-cai Liu Bi-Ming Mao Xuan Xie Feng-Cheng Jia Yan-Ping Zhu An-Xin Wu Key Laboratory of Pesticide & Chemical Biology Ministry of Education College of Chemistry Central China Normal University

An efficient one-pot synthetic protocol was developed for the synthesis of imidazo[ 1,2-a]pyridines from easily available starting materials： Aromatic ketones, α/βunsaturated ketones,β-keto esters and 2- aminopyridines. The present reaction proceeded well in MeOH under the media of I2/CuO. By using this method, the marketed drug zolimidine could be prepared easily with 95% yield. All these target products were characterized by NMR, HRMS and IR spectra. Furthermore, the target compound 3fa was determined bv X-ray crystallographic analysis.

关键词： 2-AminopyridinesAromatic ketoneslmidazo[ 1 2-a]pyridines ZolimidineOne-pot