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A plastic indentation model for sandwich beams with metallic foam cores

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Acta Mechanica Sinica 2011年第6期27卷 963-966页

作者： Zhong-You Xie Ji-lin Yu Zhi-Jun Zheng CAS Key Laboratory of Mechanical Behavior and Design of Materials University of Science and Technology of China 230026 Hefei China Department of Civil and Architectural Engineering Tongling University 244000 Tongling China

Light weight high performance sandwich composite structures have been used extensively in various load bearing *** have shown that the indentation significantly reduces the load bearing capacity of sandwiched *** this paper,the indentation behavior of foam core sandwich beams without considering the globally axial and flexural deformation was analyzed using the principle of virtual velocities.A concisely theoretical solution of loading capacity and denting profile was *** denting load was found to be proportional to the square root of the denting depth.A finite element model was established to verify the prediction of the *** load-indentation curves and the profiles of the dented zone predicted by theoretical model and numerical simulation are in good agreement.

关键词： Indentation Sandwich beam Metallic foam

Detection and suppression of narrow band RFI for synthetic aperture radar imaging

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Chinese Journal of Aeronautics 2015年第4期28卷 1189-1198页

作者： Yang lin Zheng Huifang Feng Jin Li Ning Chen Jiaqi College of Electronic Science and Engineering National University of Defense Technology Department of Space Microwave Remote Sensing System Institute of Electronics Chinese Academy of Sciences College of Computer and Information Engineering Hohai University

Radio frequency interference（RFI） is becoming more and more frequently, which makes it an important issue in SAR *** presented in synthetic aperture radar either on purpose or inadvertent will distort the useful SAR echoes, thus degrade the SAR image *** resolve this issue, a long time study was carried out to study the characteristic of the RFI through the RFIaffected spaceborne and airborne SAR *** on the narrow band nature of RFI, this paper proposes a new process which contains both RFI detection and RFI suppression.A useful subband spectral kurtosis detector is first used to detect RFI, and then its results are used for RFI *** proposed process has two advantages： one is the economization on the compute time for unnecessary interference suppression when no RFI existed; the other is improving the performance of the suppression method with knowing the exact position where RFI ***, the previous RFI suppression method––subband spectral cancelation（SSC） is supplemented and *** subband division step is also elaborated detail in this *** experiment results show that the subband spectral kurtosis detector exhibits good performance in recognizing both weak and narrow-band *** addition, the validity of the SSC method with subband spectral kurtosis detector is also validated on the real SAR echoes.

关键词： Kurtosis detector Radio frequency interference Subband spectralcancelation Synthetic aperture radar

Failure analysis of a kind of low power connector

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2007年第3期8卷 384-392页

作者： ZHOU Yi-lin ZENG Ning XU Liang-jun JORGENS Stefan Research Lab of Electric Contacts Beijing University of Posts ＆ Telecommunications Beijing 100876 China Lumberg Connect GmbH ＆ Co. KG Schalksmiihle 58579 Germany

A kind of low power connector used e.g. in household appliances was partly burned in routine experiment. The heat sources were four paralleled contacts constructed by springs (Sn/CuSn-alloy) in socket and a plug sheet (Ni/Steel) while mating. The contact interfaces were detected by scanning electronic microscope (SEM) and X-ray energy dispersive spectros- copy (XEDS), obvious wear tracks and various contaminants, including element Si, Al, Na, K, S, Cl, O, etc., were found. The contamination degrees on the four paralleled contacts were different, so that the ratio of average contact resistance on the four contacts was about 5:8:3:1. The maximum contact resistance on contacts of the plug sheet reached 28 ?. The main failure rea- sons were fretting and contamination between the contact interfaces. Fretting simulation showed that connection resistance of connectors was raised up, even to ohms level. When the current increased to 5 A, the socket housing was heated and decom- posed. By the thermal analysis, it was estimated that the connector would be burned under the lower current if the current was not evenly distributed on the four paralleled contacts caused by uneven contamination. Improvement methods for connector failure are also discussed.

关键词： Connector Thermal failure Fretting Contamination

Interstitial chemotherapy with ricin-loaded thermosensitive hydrogel in pancreatic cancer xenograft

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Hepatobiliary & Pancreatic Diseases International 2009年第4期8卷 418-423页

作者： Chen, Zhi-Kui lin, Li-Wu Weng, Xiu-Hua Xue, En-Sheng lin, Yong-Hua Fujian Med Univ Union Hosp Dept Ultrasound Fuzhou 350001 Peoples R China Fujian Med Univ Affiliated Hosp 1 Dept Pharm Fuzhou 350001 Peoples R China Fuzhou Gen Hosp Dept Gen Surg Fuzhou 350025 Peoples R China

BACKGROUND: Pancreatic cancer is one of the most aggressive malignancies, and has a poor prognosis. Despite efforts made in multiple fields, there has been little success in improving the disease-free survival rate of patients. This study was undertaken to investigate the effectiveness and feasibility of using intra-tumoral injection of ricin-loaded thermosensitive hydrogel for treatment of pancreatic cancer xenografts, attempting to develop a new treatment for human pancreatic cancer. METHODS: BALB/c-(nu/nu) nude mice were inoculated subcutaneously in the right flank with the human pancreatic cancer cells, SW1990. Fourteen days after inoculation, 32 mice, bearing tumors of volume 1.5-2.0 cm(3), were randomly assigned to one of four groups, and given an intra-tumoral injection of: (1) saline; (2) 23% w/w thermosensitive hydrogel alone; (3) ricin, 10 mu g/kg; or (4) 10 mu g/kg ricin loaded in thermosensitive hydrogel. On day 14 after administration, the tumors were excised to calculate the inhibition rate of tumor growth and perform histopathological examination. Tumor cell apoptosis was detected by flow cytometry, and RT-PCR was performed to evaluate the mRNA expression levels of Bc12 and Bax. RESULTS: Intra-tumoral injection of ricin-loaded thermosensitive hydrogel resulted in remarkable control of tumor growth. The tumor became necrotic by day 14 after administration. The histological results clearly confirmed that the tumor cells were lysed. The percentage of apoptotic cells detected by flow cytometry was higher in the ricin hydrogel group than in the other groups. Semi-quantitative RT-PCR revealed that the mRNA expression level of Bc12 was down-regulated whereas Bax was upregulated. CONCLUSIONS: Intra-tumoral injection of ricin-loaded thermosensitive hydrogel may provide an effective approach for interstitial chemotherapy in pancreatic cancer. Inducing apoptosis by downregulating Bcl2 expression and upregulating Bax expression may be a key molecular mechanism.

关键词： pancreatic neoplasm ricin hydrogel therapeutics drug delivery system

An innovative integrated system utilizing solar energy as power for the treatment of decentralized wastewater

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Journal of Environmental Sciences 2013年第2期25卷 274-279页

作者： Changfu Han Junxin Liu Hanwen Liang Xuesong Guo lin Li Research Center for Eco-Environmental Sciences Chinese Academy of Sciences

This article reports an innovative integrated system utilizing solar energy as power for decentralized wastewater treatment, which consists of an oxidation ditch with double channels and a photovoltaic （PV） system without a storage battery. Because the system operates without a storage battery, which can reduce the cost of the PV system, the solar radiation intensity affects the amount of power output from the PV system. To ensure that the power output is sufficient in all different weather conditions, the solar radiation intensity of 78 W/m 2 with 95% confidence interval was defined as a threshold of power output for the PV system according to the monitoring results in this study, and a step power output mode was used to utilize the solar energy as well as possible. The oxidation ditch driven by the PV system without storage battery ran during the day and stopped at night. Therefore, anaerobic, anoxic and aerobic conditions could periodically appear in the oxidation ditch, which was favorable to nitrogen and phosphate removal from the wastewater. The experimental results showed that the system was efficient, achieving average removal efficiencies of 88% COD, 98% NH 4 ＋ -N, 70% TN and 83% TP, under the loading rates of 140 mg COD/（g MLSS·day）, 32 mg NH 4 ＋ -N/（g MLSS·day）, 44 mg TN/（g MLSS·day） and 5 mg TP/（g MLSS·day）.

关键词： solar energy PV system wastewater treatment integrated biological reactor

An effective method for service components selection based on micro-canonical annealing considering dependability assurance

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Frontiers of Computer Science 2019年第2期13卷 264-279页

作者： Shichen ZOU Junyu lin Huiqiang WANG Hongwu LV Guangsheng FENG College of Computer Science and Technology Harbin Engineering University Harbin 150001 China Institute of Information Engineering Chinese Academy of Sciences Beijing 100093 China Department of Electrical and Computer Engineering University of Victoria Victoria V8W 3P6 Canada

Distributed virtualization changes the pattern of building software systems. However, it brings some problems on dependability assurance owing to the complex social relationships and interactions between service components. The best way to solve the problems in a distributed virtualized environment is dependable service components selection. Dependable service components selection can be modeled as finding a dependable service path, which is a multiconstrained optimal path problem. In this paper, a service components selection method that searches for the dependable service path in a distributed virtualized environment is proposed from the perspective of dependability assurance. The concept of Quality of Dependability is introduced to describe and constrain software system dependability during dynamic composition. Then, we model the dependable service components selection as a multiconstrained optimal path problem, and apply the Adaptive Bonus-Penalty Microcanonical Annealing algorithm to find the optimal dependable service path. The experimental results show that the proposed algorithm has high search success rate and quick converges.

关键词： service components selection dependability assurance distributed virtualization microcanonical annealing

Molecular engineering of ultra-sensitive fluorescent probe with large Stokes shift for imaging of basal HOCl in tumor cells and tissues

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Chinese Chemical Letters 2020年第11期31卷 2980-2984页

作者： Peng Lu Xingxing Zhang Tianbing Ren lin Yuan State Key Laboratory of Chemo/Biosensing and Chemometrics College of Chemistry and Chemical EngineeringHunan UniversityChangsha 410082China

Fluorescent probes have been widely employed in biological imaging and ***,it is always a challenge to design probes with high *** this work,based on rhodamine skeleton,we developed a general strategy to construct sensitivity-enhanced fluorescent probe with the help of theoretical calculation for the first *** a proof of concept,we synthesized a series of HOCl *** results showed that with the C-9 of pyronin moiety of rhodamine stabilized by an electron donor group,probe DQF-S exhibited an importantly enhanced sensitivity(LOD:0.2 nmol/L)towards HOCl together with fast response time(650 nm)and large Stokes *** studies indicated that DQF-S can not only effectively detect basal HOCl in various types of cells,but also be successfully applied to image tumor tissue in *** results demonstrate the potential of our design as a useful strategy to develop excellent fluorescent probes for bioimaging.

关键词： Fluorescent probes High sensitivity Hypochlorous acid(HOCl) Large Stokes shift Fluorescence imaging

Effect of rare earth and alloying elements on the thermal conductivity of austenitic medium manganese steel

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International Journal of Minerals,Metallurgy and Materials 2017年第6期24卷 670-674页

作者： Shao-chun Chen Hong-xiang Ye Xin-qiang lin School of Mechanical Engineering and Automation Fuzhou University Fuzhou 350116 China

The influence of different contents of Cr, Mo, and rare earth element(RE) additives on the thermal conductivity of austenitic medium manganese steel was studied and discussed. The results show that the addition of Cr in medium manganese steel can improved the ordering of C–Mn atomic clusters, so as to improve the steel's thermal conductivity. However, Cr will lead to precipitation of a great deal of carbides in medium manganese steel when its content is greater than 4wt%. These carbides would aggregate around the grain boundary, and as a result, the thermal conductivity is decreased. By the addition of Mo whose content is about 2wt%, spherical carbides will be formed, thus improving the thermal conductivity of the medium manganese steel. The interaction between rare earth elements and alloying elements will raise both the thermal conductivity and the wear-resisting property of medium manganese steel.

关键词： medium manganese steel alloying elements rare earth thermal conductivity

Prevalence and risk factors for Barrett’s esophagus in Taiwan

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World Journal of Gastroenterology 2019年第25期25卷 3231-3241页

作者： Yan-Hua Chen Hsien-Chung Yu Kung-Hung lin Huey-Shyan lin Ping-I Hsu Division of Gastroenterology and Hepatology Department of Internal MedicineKaohsiung Veterans General HospitalKaohsiung 81362Taiwan Health Evaluation Center Kaohsiung Veterans General HospitalKaohsiung 81362Taiwan Department of Nursing Meiho UniversityNeipu TownshipPingtung County 91202Taiwan Institute of Health Care Management Department of Business ManagementNational Sun Yat-Sen UniversityKaohsiung 80424Taiwan Department of Health-Business Administration Fooyin UniversityKaohsiung 83102Taiwan National Yang Ming University Taipei 12221Taiwan

BACKGROUND Barrett’s esophagus(BE)is a pre-malignant condition associated with the development of esophageal *** prevalence of BE in the general populations of Asian countries ranges from 0.06%to 1%.However,with lifestyle changes in Asian countries and adoption of western customs,the prevalence of BE might have *** To determine the current prevalence of BE in Taiwan,and to investigate risk factors predicting the presence of *** This retrospective study was conducted at the Health Evaluation Center of Kaohsiung Veterans General Hospital in *** January 2015 and December 2015,3385 subjects undergoing routine esophagogastroduodenoscopy examinations as part of a health check-up at the Health Evaluation Center were *** characteristics and endoscopic findings were carefully *** with endoscopic findings consistent with BE awaiting histological evaluation were judged as endoscopically suspected esophageal metaplasia(ESEM).BE was defined based on extension of the columnar epithelium≥1 cm above the gastroesophageal junction and was confirmed based on the presence of specialized intestinal metaplasia(IM)in the metaplastic esophageal *** factors of subjects with BE and subjects without BE were compared,and the risk factors predicting BE were *** A total of 3385 subjects(mean age,51.29±11.42 years;57.1%male)were included in the study,and 89 among them were confirmed to have IM and presence of goblet cells via biopsy *** majority of these individuals were classified as short segment BE(n=85).The overall prevalence of BE was 2.6%.Multivariate analysis disclosed that old age[odds ratio(OR)=1.033;95%confidence interval(CI):1.012-1.055;P=0.002],male gender(OR=2.106;95%CI:1.145-3.872;P=0.017),ingestion of tea(OR=1.695;95%CI:1.043-2.754;P=0.033),and presence of hiatal hernia(OR=3.037;95%CI:1.765-5.225;P<0.001)were significant risk factors predicting *** independent risk facto

关键词： Barrett’s esophagus Prevalence Risk factors Intestinal metaplasia Taiwan