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Adaptive asymptotic fault-tolerant tracking of uncertain nonlinear systems with unknown control directions

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Journal of Control and Decision 2022年第3期9卷 301-310页

作者： jin-zi Yang Yuan-Xin Li Shaocheng Tong Department of Science Liaoning University of TechnologyJinzhouLiaoningPeople’s Republic of China

In the article,the issues of asymptotic adaptive tracking control for the uncertain nonlinear systems in the presence of actuator faults and unknown control directions are *** using the properties of the Nussbaum function and backstepping technique,the problems resulting from the unknown signs of the nonlinear control functions are circumvented ***,a new adaptive asymptotic tracking control method is presented with the fault-tolerant control framework,which is capable of realising zero-tracking *** stability of the controlled system is ensured through fractional Lyapunov stability ***,the validity of the raised scheme is verified by a simulation example.

关键词： Uncertain nonlinear system fault-tolerant control(FTC) adaptive asymptotic tracking control unknown control directions

Theoretical analysis and experimental study of an air inflated membrane structure

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2010年第1期11卷 25-33页

作者： jing-hai GONG Xiu-ying YANG zi-zhao ZHANG jin-cheng ZHAO Department of Civil Engineering Shanghai Jiao Tong University Sharighai 200240 China

In this paper,an experimental study of an air inflated membrane was carried out based on the China National Stadium (the Bird's Nest). After the 2008 Olympic Games,it was apparent that the future use of the Bird's Nest would be enhanced if rainfall could be prevented from entering the stadium. The installation of an air inflated membrane across the opening of the steel structure was proposed as a solution to this problem. To verify the scheme,a theoretical analysis and experimental study of an air inflated membrane was carried out. Experimental and computational models were developed,form-finding was carried out using both experimental and theoretical methods,and the results from the two approaches,including the deflection of the air inflated membrane and deformation of the support structure,were analyzed and compared. The force-transfer path and deformation of the air inflated membrane under loads was studied. Conclusions and suggestions are presented.

关键词： China National Stadium Air inflated membrane Form-finding

Rh nanoparticles stabilized by PEG-substituted triphenyl-phosphine:A highly active and recyclable catalyst for aqueous biphasic hydrogenation of benzene

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Chinese Chemical Letters 2010年第9期21卷 1067-1070页

作者： Ya Dong Lu Yan Hua Wang zi Lin jin State Key Laboratory of Fine Chemicals Dalian University of Technology Dalian 116012 China

Rh nanoparticles stabilized by PEG-substituted triphenyl-phosphine（PETPP,P[C6H4-p-（OCH2CH2）nOH]3） combining double stabilization effects demonstrated high activity and good recyclability in aqueous biphasic hydrogenation of *** value of turnover frequency（TOF） was 3333 h^-***,the rhodium nanoparticle catalyst could be easily recycled for five times without loss in activity.

关键词： Hydrogenation Nanoparticles Rhodium PETPP Aqueous biphasic catalysis

A ligand-free Heck reaction catalyzed by the in situ-generated palladium nanoparticles in PEG-400

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Chinese Chemical Letters 2010年第12期21卷 1411-1414页

作者： Wei Han Ning Liu Chun Liu zi Lin jin State Key Laboratory of Fine Chemicals School of Chemical Engineering Dalian University of Technology Dalian 116012 China

A ligand-free Heck reaction catalyzed by in situ-generated palladium nanoparticles in PEG-400 has been *** catalytic system is a simple and active protocol for the Heck reaction of aryl halides under mild *** experiments demonstrated that the Heck reaction catalyzed by the palladium nanoparticles in situ-generated under the Heck reaction conditions was carried out much quicker than that by the in ex situ-generated ones.

关键词： rn situ nanocatalysis Palladium nanoparticles Heck reaction Polyethylene glycol

New insights in diagnosis and treatment of gastroenteropancreatic neuroendocrine neoplasms

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World Journal of Gastroenterology 2022年第17期28卷 1751-1767页

作者： Feng Yin zi-Hao Wu jin-Ping Lai Department of Pathology and Anatomical Sciences University of MissouriColumbiaMO 65212United States Department of Surgery University of MissouriColumbiaMO 65212United States Department of Pathology Kaiser Permanente Sacramento Medical CenterSacramentoCA 95825United States

Gastroenteropancreatic neuroendocrine neoplasms(GEP-NENs)are rare epithelial neoplasms derived from pluripotent endocrine cells along the gastrointestinal tract and ***-NENs are classified into well-differentiated neuroendocrine tumors and poorly differentiated neuroendocrine *** overlapping morphological features,GEP-NENs vary in molecular biology,epigenetic,clinical behavior,treatment response,and prognosis features and remain an unmet clinical *** this review,we introduce recent updates on the histopathologic classification,including the tumor grading and staging system,molecular genetics,and systemic evaluation of the diagnosis and treatment of GEP-NENs at different anatomic sites,together with some insights into the diagnosis of challenging and unusual *** also discuss the application of novel therapeutic approaches for GEP-NENs,including peptide receptor radionuclide therapy,targeted therapy,and immunotherapy with immune checkpoint *** findings will help improve patient care with precise diagnosis and individualized treatment of patients with GEP-NENs.

关键词： Gastroenteropancreatic neuroendocrine neoplasms Neuroendocrine tumours Neuroendocrine carcinoma World Health Organization classification Diagnosis Treatment

Effect of Sequence Structure on Wetting Behaviors of Fluorinated Methacrylate Polymers Based on Perfluorohexylethyl Methacrylate and Stearyl Acrylate

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Chinese Journal of Polymer Science 2017年第9期35卷 1061-1072页

作者： zi-xu gu jun cheng ming-zu zhang jin-lin he 倪沛红 College of Chemistry Chemical Engineering and Materials Science State and Local Joint Engineering Laboratory for Novel Functional Polymeric Materials Jiangsu Key Laboratory of Advanced Functional Polymer Design and Application Suzhou Key Laboratory of Macromolecular Design and Precision Synthesis Soochow University Suzhou 215123 China

Due to the non-crystalline properties of short chain perfluoroalkyl groups, using short chain perfluoroalkyl to stabilize low surface free energy polymers has been a challenging task. In this study, we prepare a series of random copolymers poly（perfluorohexylethyl methacrylate）-co-poly（stearyl acrylate）（P13FMA-co-PSA） and block copolymers poly（perfluorohexylethyl methacrylate）-b-poly（stearyl acrylate）（P13FMA-b-PSA）, and systematically investigate the effects of the sequence structure and the content of 13FMA of the fluorinated copolymers on surface free energy and surface reorganization. Static/dynamic contact angle goniometry and water/oil repellency analyses demonstrate that the random polymer P13FMA-co-PSA could not achieve low surface free energy and low surface reorganization at the same time. In contrast, for the block copolymer P13FMA-b-PSA, both low surface free energy and low surface reorganization are acquired simultaneously. The results of X-ray photoelectron spectroscopy （XPS）, dynamic contact angle goniometry and differential scanning calorimetry （DSC） reveal the above-mentioned properties. The consecutive 13FMA segments improve the surface fluorine density, while the consecutive SA chains enhance the crystallinity of the SA segments, and further hinder the surface reorganization of the perfluoroalkyl groups. Therefore, P13FMA-b-PSA exhibits a higher utilization efficiency of fluorine atoms and a better structural stability than P13FMA-co-PSA.

关键词： Surface free energy Surface reorganization Perfluorohexylethyl methacrylate (13FMA) Stearyl acrylate (SA) Water/oil repellency

Expression of Cyclooxygenase-2 and Its Relationship with Mismatch Repair and Microsatellite Instability in Hereditary Nonpolyposis Colorectal Cancer

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Chinese Medical Sciences Journal 2010年第4期25卷 206-210页

作者： Peng jin Jian-qiu Sheng Ying-hui Zhang Ai-qin Li zi-tao Wu Shi-rong Li Department of Gastroenterology The Military General Hospital of Beijing Beijing 100700 China

Objective To investigate cyclooxygenase-2 (COX-2) expression and its relationship with mismatch repair (MMR) protein expression and microsatellite instability (MSI) in hereditary nonpolyposis colorectal cancer (HNPCC). Methods A total of 28 cases of colorectal adenoma and 14 cases of colorectal carcinoma were collected between July 2003 and July 2007 from 33 HNPCC families. Sporadic colorectal adenoma (n=32) and carcinoma patients (n=24) served as controls. With samples of tumor tissues and normal colonic mucosa collected from the patients, the protein expressions of COX-2 and MMR (hMLH1, hMSH2, and hMSH6) were examined with immunohistochemical assay. Frequency of MSI in five standard MSI loci BAT25, BAT26, D2S123, D5S346, and D17S250 were analyzed by means of polymerase chain reaction. Results The rate of COX-2 high-expression was 53.6% (15/28) and 42.9% (6/14) in HNPCC adenoma and carcinoma; 62.5% (20/32) and 91.7% (22/24) in sporadic adenoma and carcinoma, respectively. That rate was lower in HNPCC carcinoma than in sporadic carcinoma (P<0.05). MMR-deletion rate and percentage of high-frequency MSI (MSI-H) in HNPCC carcinoma were higher than those in sporadic colorectal carcinoma [both 71.4% (10/14) vs. 12.5% (3/24), both P<0.01]. Among the 10 MMR-deficient HNPCC carcinoma patients, COX-2 low-expression was observed in 8 cases (80.0%), while COX-2 high-expression was observed in all of the 4 MMR-positive HNPCC carcinoma cases (P<0.05). In comparison to MMR positive HNPCC carcinoma, HNPCC adenoma, and sporadic carcinoma, COX-2 expression was significantly lower in corresponding MMR-deficient cases (all P<0.05). The rates of COX-2 low-expression in HNPCC adenoma, HNPCC carcinoma, and sporadic carcinoma with MSI-H were significantly higher than those in the cases with microsatellite stability (all P<0.05). Conclusion COX-2 is expressed at a low level in HNPCC carcinoma, different from the high COX-2 expression in sporadic carcinoma.

关键词： colorectal cancer hereditary nonpolyposis colorectal cancer cyclooxygenase-2 mismatch repair microsatellite instability

Flow Fields with Vortex in a Small Semi-open Axial Fan

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Journal of Thermal Science 2009年第4期18卷 294-300页

作者： Norimasa. Shiomi Yoichi Kinoue Ying zi jin Toshiaki Setoguchi Kenji Kaneko Department of Mechanical Engineering Saga University 1 Honjo-machi Saga 840-8502 Japan Institute of Mechatronics Zhejiang Sci-Tech University Xiasha Higher Educational Zone Hangzhou 310018 China

In order to clarify the effect of tip clearance （TC） size on fan performance and the flow field at rotor outlet in a small semi-open axial fan, the experimental investigation was carried out. The tip diameter of test fan rotor was 180mm and test TC sizes were lmm （TC=1mm） and 4mm （TC=4mm）. Fan characteristics tests were carried out for two cases of TC size and three-dimensional velocity fields at rotor outlet were measured using a single slant hot-wire probe at four flow-rate conditions. As a result, it was found that the pressure - flow-rate characteristics curves for two cases showed almost the same tendency. However, the ensemble averaged velocity profiles along radial measurement stations of TC-4mm largely changed compared with that of TC=1mm in cases of small flow-rate condition. From the phase-locked averaging results, it was also found that the vortex existed in the rotor outlet flow field of high flow-rate condition for each TC case. Compared with the vortices for TC=1mm and TC=4mm, the vortex for TC=4mm was stronger than that for TC=1mm.

关键词： fan semi-open type vortex tip clearance

Flow Fields with Tip Leakage Vortex in a Small Axial Cooling Fan

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Journal of Thermal Science 2008年第2期17卷 156-162页

作者： Norimasa Shiomi Ying zi jin Kenji Kaneko Yoichi Kinoue T. Setoguchi Department of Mechanical Engineering Saga University 1 Honjo-machi Saga 840-8502 Japan Institute of Mechatromcs Zhejiang Sci-Tech University Hangzhou 310018 China

In order to improve the fan characteristics, especially efficiency and noise level of a small axial cooling fan with a large tip clearance, the internal flow measurements with tip leakage vortex were carried out at fan rotor outlet us- ing an I-type hot-wire probe. The probe was set toward two directions, parallel and normal to the meridional plane of test fan, and the two directional velocity components were measured. From the result of fan test it was found that the test fan didn＇t have the unstable characteristic with a positive gradient on its pressure - flow-rate curve. From the results of velocity measurement it was observed that the tip leakage vortex exited at maximum efficiency flow-rate and large flow-rate conditions. However, at small flow-rate conditions the tip leakage vortex was not observed and it was found that the flow field were enlarged toward radial outwards

关键词： Axial fan cooling fan internal flow and tip leakage vortex