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Numerical simulation of tomographic-SAR imaging and object reconstruction using compressive sensing with L_(1/2)-norm regularization

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Chinese Science Bulletin 2014年第33期59卷 4600-4607页

作者： Xiao Wang feng xu Ya-Qiu Jin Key Laboratory for Information Science of Electromagnetic Waves (MoE) Fudan University

By making use of multiple acquisitions of synthetic aperture radar(SAR) observations over the same area, tomographic-SAR(tomo-SAR) technology can achieve three-dimensional(3-D) imaging of the objects of interest. The compressive sensing(CS) approach has been applied to deal with the sparseness of the elevation *** to its sparsity and convexity, the L1-norm regularization, as an approximated L0-norm with an exact solution,has been employed in CS to reconstruct the reflectivity profile of the objects. In this paper, based on our studies on polarimetric scattering and SAR imaging simulations, we produce numerical multi-pass tomo-SAR observations of the terrain object. Then, we present the CS with novel L1/2-norm regularization to realize 3-D reconstruction. As a non-convex optimization problem, the L1/2-norm regularization is solved by an iterative algorithm. This numerical simulation of tomo-SAR imaging and 3-D reconstruction of the object modeling can be of great help for parameterized analysis of tomo-SAR imagery. As an example, a tomo-SAR image and 3-D reconstruction of the Beijing National Stadium model are presented.

关键词： SAR成像 L1范数数值模拟压缩断层正规化 SAR图像三维重建

Online Learning over a Decentralized Network Through ADMM

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Journal of the Operations Research Society of China 2015年第4期3卷 537-562页

作者： Hao-feng xu Qing Ling Alejandro Ribeiro Department of Automation University of Science and Technology of ChinaHefei 230026China Department of Electrical and Systems Engineering University of PennsylvaniaPhiladelphiaUSA

In this paper,we focus on the decentralized online learning problem where online data streams are separately collected and collaboratively processed by a network of decentralized *** to centralized batch learning,such a framework is faithful to the decentralized and online natures of the data *** propose an online decentralized alternating direction method of multipliers that efficiently solves the online learning problem over a decentralized *** prove its O(√T)regret bound when the instantaneous local cost functions are convex,and its O(log T)regret bound when the instantaneous local cost functions are strongly convex,where T is the number of *** regret bounds are in the same orders as those of centralized online *** experiments on decentralized online least squares and classification problems demonstrate effectiveness of the proposed algorithm.

关键词： Multi-agent network Decentralized optimization Online learning

Effectiveness and safety of continuous wound infiltrationfor postoperative pain management after open gastrectomy

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World Journal of Gastroenterology 2016年第5期22卷 1902-1910页

作者： Xing Zheng xu feng Xiu-Jun Cai Department of Anesthesiology Sir Run Run Shaw HospitalZhejiang UniversitySchool of MedicineHangzhou 310016Zhejiang ProvinceChina Department of General Surgery Sir Run Run Shaw HospitalZhejiang UniversitySchool of MedicineHangzhou 310016Zhejiang ProvinceChina

AIM: To prospectively evaluate the effectiveness and safety of continuous wound infiltration(CWI) for pain management after open gastrectomy. METHODS: Seventy-five adult patients with American Society of Anesthesiologists(ASA) Physical Status Classification System(ASA) grade 1-3 undergoing open gastrectomy were randomized to three groups. Group 1 patients received CWI with 0.3% ropivacaine(group CWI). Group 2 patients received 0.5 mg/m L morphine intravenously by a patient-controlled analgesia pump(PCIA)(group PCIA). Group 3 patients received epidural analgesia(EA) with 0.12% ropivacaine and 20 μg/m L morphine with an infusion at 6-8 m L/h for 48 h(group EA). A standard general anesthetic technique was used for all three groups. Rescue analgesia(2 mg bolus of morphine, intravenous) was given when the visual analogue scale(VAS) score was ≥ 4. The outcomes measured over 48 h after the operation were VAS scores both at rest and during mobilization, total morphine consumption, relative side effects, and basic vital signs. Further results including time to extubation, recovery of bowel function, surgical wound healing,mean length of hospitalization after surgery, and the patient's satisfaction were also ***: All three groups had similar VAS scores during the first 48 h after surgery. Group CWI and group EA, compared with group PCIA, had lower morphine consumption(P < 0.001), less postoperative nausea and vomiting(1.20 ± 0.41 vs 1.96 ± 0.67, 1.32 ± 0.56 vs 1.96 ± 0.67, respectively, P < 0.001), earlier extubation(16.56 ± 5.24 min vs 19.76 ± 5.75 min, P < 0.05, 15.48 ± 4.59 min vs 19.76 ± 5.75 min, P < 0.01), and earlier recovery of bowel function(2.96 ± 1.17 d vs 3.60 ± 1.04 d, 2.80 ± 1.38 d vs 3.60 ± 1.04 d, respectively, P < 0.05). The mean length of hospitalization after surgery was reduced in groups CWI(8.20 ± 2.58 d vs 10.08 ± 3.15 d, P < 0.05) and EA(7.96 ± 2.30 d vs 10.08 ± 3.15 d, P < 0.01) compared with group PCIA. All three groups had similar patien

关键词： Postoperative pain Gastrectomy Woundinfiltration Epidural analgesia Patient-controlledanalgesia Incision infection Ropivacaine

Radical induced quartet photosensitizers with high ^(1)O_(2) production for in vivo cancer photodynamic therapy

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Science China Chemistry 2021年第3期64卷 488-498页

作者： feng xu Haoying Ge Ning xu Cheng Yang Qichao Yao Saran Long Wen Sun Jiangli Fan Xinsheng xu Xiaojun Peng State Key Laboratory of Fine Chemicals Dalian University of TechnologyDalian 116024China School of Physics and Electronic Information Anhui Normal UniversityWuhu 241000China Anhui Province Key Laboratory of Optoelectric Materials Science and Technology Anhui Normal UniversityWuhu 241000China Ningbo Institute of Dalian University of Technology Ningbo 315016China

Singlet oxygen(^(1)O_(2)) is a strong oxidant which plays important roles in photodynamic therapy(PDT). The exploitation of photosensitizers with high ^(1)O_(2) production is crucial to improve PDT efficiency. In this study, a radical labeled quartet photosensitizer Cy-DENT is reported with high singlet oxygen quantum yield(Φ_(Δ)=32.3%) due to a radical enhanced inter-system crossing(ISC) process. After the introduction of 2,2,6,6-tetramethylpiperidinyloxy(TEMPO) radical, quartet state ^(4)[R,T] of CyDENT could be formed to give an over 20-fold enhancement of singlet oxygen quantum yield compared to Cy-DEN(without TEMPO radical) under irradiation of near infrared(NIR) light. In addition, the ^(1)O_(2 )production is well controlled by varying the electron-donating ability of the terminal substituent group. Cy-DENT possesses good cell permeability and is localized in mitochondria. Under the irradiation of 700 nm light, Cy-DENT can produce high levels of ROS to destroy the mitochondria membrane potential and induce cell apoptosis. Through the encapsulation of PEG-SS-PCL micelle, Cy-DENT can be effectively delivered to tumors and suppresses the tumor growth after PDT treatment.

关键词： singlet oxygen photodynamic therapy quartet photosensitizer TEMPO radical

Polymerization of Methyl Methacrylate with Samarocene Complex Supported on Mesoporous Silica

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Chinese Chemical Letters 2001年第9期12卷 821-822页

作者： xu feng NI Zhi Quan SHEN Hajime YASUDA Institute of Polymer Science Zhejiang UniversityHangzhou 310027 Department of Applied Chemistry Faculty of EngineeringHiroshima UniversityHigashi-Hiroshima 724Japan

Samarocene complex was supported on a series of mesoporous silica with various pore sizes. Polymerization of methyl methacrylate (MMA) by these catalysts provide highly syndiotactic PMMAs with higher molecular weights... 详细信息

关键词： Mesoporous silica supported catalyst samarocene complex

Influencing factors for catalytic oxidation of mine gas to methanol in liquid phase

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Chinese Journal Of Geochemistry 2014年第2期33卷 183-186页

作者： ZHU Lihua xu feng BI Yewu SHEN Bin Heilongjiang University of Science and Technology

The influencing factors for liquid phase catalytic oxidation of mine gas to methanol(in form of CH3COOCH3) are studied using the self-established experimental apparatus. The results show that CH3COOCH3(target product) is obtained by using CH3COOH as reaction solvent, and the yield of target product increases with the increasing of reaction temperature, gas pressure and reaction time. In the mine gas-Pd(OAc)2-CH3COOH system, the yield of CH3COOCH3 increases with the increasing of addition of Pd(OAc)2 which is redox catalyst for mine gas conversion. The yield of CH3COOCH3 will be greatly improved by composite additional oxidant which is obtained by equimolar mix of p-benzoquinone with NO2.

关键词：液相催化氧化矿井瓦斯影响因素甲醇还原催化剂实验装置反应溶剂反应温度

Preparation of amphiphilic graft copolymer with polyisoprene backbone by combination of anionic polymerization and "click" reaction

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Chinese Chemical Letters 2012年第3期23卷 347-350页

作者： Fei Shao xu feng Ni Zhi Quan Shen MOE Key Laboratory of Macromolecular Synthesis and Functionalization Department of Polymer Science and EngineeringZhejiang UniversityHangzhou 310027China

A novel graft copolymer consisting of polyisoprene backbone and hydrophilic side chain with carbamic acid ester functional group was prepared via thiol-ene＂click＂reaction and alcohol-isocyanate *** was synthesized by anionic polymerization using n-butyl lithium as initiator,and the pendant hydroxyl groups were introduced by the thiol-ene reaction of mercaptoethanol with the double bond of 1,2-addition units of PI backbone in the presence of radical initiator azobisisobutyronitrile. Isocyanate end group capped poly（ethylene glycol）（mPEG-NCO） was grafted onto the PI backbone through alcoholisocyanate reaction between the pendant hydroxyl groups and isocyanate group of *** structure of the graft copolymer were characterized and confirmed by means of size-exclusion chromatography,~1H NMR and FTIR spectroscopy.

关键词： Graft-copolymer Thiol-ene addition Isocyanate Click reaction

Preparation and Reactions of Perfluoroalkanesulfenyl Chlorides

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Chinese Journal of Chemistry 2017年第4期35卷 442-446页

作者： Ze-feng xu Min Jiang Jin-Tao Liu Key Laboratory of Organofluorine Chemistry Shanghai Institute of Organic Chemistry Chinese Academy of Sciences Shanghai 200032 China Department of Chemistry Zhejiang Sci-Tech University Xiasha West Higher Education District Hangzhou Zhejiang 310018 China

Several perfluoroalkanesulfenyl chlorides were prepared from the corresponding perfluoroalkanesulfenic acids in high yields, and their reactions with thiol, amine, arene and alkene were studied. A series of perfluoroal- kyl-containing disulfides, sulfonamides, aryl sulfides and a-chlorosulfides were synthesized under mild conditions.

关键词： perfluoroalkanesulfenyl chloride perfluoroalkanesulfenyl acid substitution disulfide addition

Evodiagenine and dievodiamine,two new indole alkaloids from Evodia rutaecarpa

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Chinese Chemical Letters 2010年第5期21卷 596-599页

作者： Qi Zhi Wang Jing Yu Liang xu feng Institute of Botany Jiangsu Province and Chinese Academy of SciencesNanjing 210014China Department of Natural Medicinal Chemistry China Pharmaceutical UniversityNanjing 210009China

Two new indole alkaloids,evodiagenine 1 and dievodiamine 2 were isolated from the fruits of Evodia rutaecarpa(Juss.) Benth. The structure of compounds 1 and 2 were elucidated by comprehensive spectroscopic analysis an... 详细信息

关键词： Evodia rutaecarpa(Juss.) Benth Evodiagenine Dievodiamine