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Accuracy details in realistic cFD modeling of an industrial centrifugal pump in direct and reverse modes

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journal of Thermal Science 2010年第6期19卷 491-499页

作者： j.c. Páscoa F. j. Silva j.S. Pinheiro D.j. Martins Department of Electromechanical Engineering Center for Aerospace Sciences and Technology University of Beira Interior EFAFLU Bombas e Ventiladores S.A. R. S. Brás 269 Apartado 23 4494-909 Póvoa do Varzim Portugal

Numerical computation of the flowfield inside a pump is herein used as a numerical laboratory, subj.c. to the limitations of modeling assumptions and to experimental verification. A numerical computation of the flow inside a real industrial centrifugal pump is performed that includes a very sophisticated geometry. conversely to other computations, in this test case no simplification of the geometry was introduced. Numerical computations are obtained using Spalart-Allmaras turbulence model. A detailed analysis of the turbulent flowstructure is performed for the design point and two off design conditions. Additional computations were performed in order to compare the numerical and experimental pump characteristics; these were obtained under normalized testing conditions. Further computations are presented for the pump working in reverse turbine mode (PAT). Detailed analyses of the flow allow a comparison of the internal flow losses when the pump is operating in direct and reverse mode. This is also useful to help in the selection of an adequate pump geometry that can work in both modes with best efficiency.

关键词： centrifugal pump impeller turbulence modeling Spalart-Allmaras PAT

Synthesis of coral-like structures of Pr-Yb co-doped YIG: Structural,optical, magnetic and antimicrobial properties

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journal of Rare Earths 2024年第3期42卷 543-554,I0004页

作者： A.Fernandez Francisca P.Araujo Y.Guerra S.castro-Lopes j.Matilla-Arias Idglan S.de Lima Edson c.Silva-Filho josy A.Osajima F.Guerrero R.Pena-Garcia Federal University of Piau Graduate Program in Materials Science and EngineeringTeresinaPIBrazil Federal Rural University of Pernambuco Academic Unit of Cabo de Santo AgostinhoCabo de Santo AgostinhoPEBrazil Federal University of Piaui Department of PhysicTeresinaPBrazil Federal University of Pernambuco Graduate Program in Materials ScienceRecifePEBrazil University of Granma Departmentof Basic Sciences and Applied InformaticsFaculty of Technical SciencesBayamoCuba Federal University of Amazonas Department of PhysicManausAMBrazil Federal University of Pernambuco Department of PhysicRecifePEBrazil

coral-like structures of the Y_(3-x)Pr_(x)Fe_(5-y)Yb_(y)O_(12),(0.00 ≤ x ≤ 0.04, 0.00 ≤ y ≤ 0.02) compound were synthesized using the sol-gel method. Structural investigation certified the YIG cubic crystal structure formation, without any secondary phase. It is shown that, the relatively large ionic radius of the dopant cations results in an expansion of the lattice parameter, variations in the Iona-O-Iondangle, Iona-O,Iond-O and Ionc-O bond distances and decrease in the average crystallite size. Fourier transform infrared(FTIR) and Raman measurements are essential to testify the single-phase formation of YIG crystal structure and are observed changes in the stretching and vibrational modes, respectively. The morphological study, energy dispersive spectroscopy(EDS) spectra and textural properties show corallike structures, peaks associated with Pr^(3+) and Yb^(3+) atoms and the effect of dopants on surface area,diameter, and pore volume, respectively. The optical analysis from diffuse reflectance spectra witnessed an increase in the optical gap band, a decrease in Urbach energy and blue shift in the charge transfer,correlated with the expansion of the unit cell due to the dopant's insertion in the YIG structure. A typical ferrimagnetic behavior is exhibited by the Y_(3-x)Pr_(x)Fe_(5-y)Yb_(y)O_(12)compound. The saturation magnetization(M_(s)), cubic anisotropy constant(K_(1)) and coercive field(H_(c)) increase with the Pr^(3+)cations content, as consequence of their magnetic nature and distribution around of Fe^(3+)ions due to the coexistence with the Yb^(3+). Finally, for the first time, antibacterial tests by mean of the direct contact method were performed for YIG co-doped with Pr^(3+)and Yb^(3+)and it is shown that, relatively high dosages of Pr^(3+) cations favored the activity against S. aureus, therefore, a new biological property for YIG doped with rare earths is presented.

关键词： Yttrium iron garnet(YIG) coral-like structures Rare earths Band gap energy Magnetic properties Antimicrobial properties

AUTOMATIc PATENT DOcUMFNT SUMMARIZATION FOR cOLLABORATIVE KNOWLEDGE SYSTEMS AND SERVIcES

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journal of Systems Science and Systems Engineering 2009年第1期18卷 71-94页

作者： Amy j.c. TRAPPEY charles V. TRAPPEY chun-Yi WU Dept. of Industrial Engineering and Management National Taipei University of Technology Taiwan China Dept. of lndustrial Engineering and Engineering Management National Tsing Hua University Taiwan China Dept. of Management Science National Chiao Tung University Taiwan China

Engineering and research teams often develop new products and technologies by referring to inventions described in patent databases. Efficient patent analysis builds R＆D knowledge, reduces new product development time, increases market success, and reduces potential patent infringement. Thus, it is beneficial to automatically and systematically extract information from patent documents in order to improve knowledge sharing and collaboration among R＆D team members. In this research, patents are summarized using a combined ontology based and TF-IDF concept clustering approach. The ontology captures the general knowledge and core meaning of patents in a given domain. Then, the proposed methodology extracts, clusters, and integrates the content of a patent to derive a summary and a cluster tree diagram of key terms. Patents from the International Patent classification （IPc） codes B25c, B25D, B25F （categories for power hand tools） and B24B, c09G and H011 （categories for chemical mechanical polishing） are used as case studies to evaluate the compression ratio, retention ratio, and classification accuracy of the summarization results. The evaluation uses statistics to represent the summary generation and its compression ratio, the ontology based keyword extraction retention ratio, and the summary classification accuracy. The results show that the ontology based approach yields about the same compression ratio as previous non-ontology based research but yields on average an 11% improvement for the retention ratio and a 14% improvement for classification accuracy.

关键词： Semantic knowledge service key phrase extraction document summarization text mining,patent document analysis

光谱探针法确定Eu^(3+):ThO_2的格位对称性及选择激发下样品的光致发光研究

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物理学报 2000年第9期49卷 1859-1866页

作者：尹民 j.c. KRUPA 中国科学技术大学结构研究开放实验室合肥230026 法国国家科学研究中心Orsay核物理研究所

测量和分析了不同温度下Eu3 + :ThO2 的激发光谱、发射光谱和荧光衰减曲线 .Eu3 + :ThO2 晶体是用熔融法生长的 .通过 12K下格位选择激发下的发射光谱测量 ,利用晶场理论 ,确定了Eu3 + 在ThO2 占据Oh 和c3v两种格位 .列表给出了两种格位... 详细信息

测量和分析了不同温度下Eu3 + :ThO2 的激发光谱、发射光谱和荧光衰减曲线 .Eu3 + :ThO2 晶体是用熔融法生长的 .通过 12K下格位选择激发下的发射光谱测量 ,利用晶场理论 ,确定了Eu3 + 在ThO2 占据Oh 和c3v两种格位 .列表给出了两种格位Eu3 + 离子的晶场能级和室温及 12K下的荧光寿命 .讨论了温度对能量传递过程的影响以及低温下激发峰红移的机理 .

关键词：光谱探针选择激光光谱氧化钍格位对称性发光

SPEcIAL ISSUE EDITORIAL

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journal of Systems Science and Systems Engineering 2010年第2期19卷 129-130页

作者： Amy j.c. TRAPPEY Fataneh Taghaboni DUTTA Kai-Ying cHEN college of Management National Taipei University of Technology & Department of lndustrial Engineering and Engineering Management National Tsing Hua University Taiwan China Department of Business Administration College of Business University of Illinois at Urbana-Champaign USA Department of Industrial Engineering and Management National Taipei University of Technology Taiwan China

This special issue of joumal of Systems Science and Systems Engineering recognizes the contributions of authors and participants in the 16th ISPE International conference on concurrent Engineering （cE2009）, 2009 ASME International Manufacturing Science and Engineering conference （MSEc） and 2009 IEEE International conference on Systems, Man and cybernetics. Among related papers presented in these conferences, the guest editors have selectively identified and invited the authors to re-write and extend their works to full-length papers for re-submission to the special issue.

关键词： SPEcIAL ISSUE EDITORIAL

Generalized polynomial chaos expansion by reanalysis using static condensation based on substructuring

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Applied Mathematics and Mechanics(English Edition) 2024年第5期45卷 819-836页

作者： D.LEE S.cHANG j.LEE Department of Automotive Engineering Hanyang UniversitySeoul 04763Republic of Korea School of Mechanical Engineering Chungnam National UniversityDaejeon 34134Republic of Korea Department of Mechanical Robotics and Energy EngineeringDongguk UniversitySeoul 04620Republic of Korea

This paper presents a new computational method for forward uncertainty quantification(UQ)analyses on large-scale structural systems in the presence of arbitrary and dependent random *** method consists of a generalized polynomial chaos expansion(GPcE)for statistical moment and reliability analyses associated with the stochastic output and a static reanalysis method to generate the input-output data *** the reanalysis,we employ substructuring for a structure to isolate its local regions that vary due to random *** allows for avoiding repeated computations of invariant substructures while generating the input-output data *** substructuring with static condensation further improves the computational efficiency of the reanalysis without losing ***,the GPcE with the static reanalysis method can achieve significant computational saving,thus mitigating the curse of dimensionality to some degree for UQ under high-dimensional *** numerical results obtained from a simple structure indicate that the proposed method for UQ produces accurate solutions more efficiently than the GPcE using full finite element analyses(FEAs).We also demonstrate the efficiency and scalability of the proposed method by executing UQ for a large-scale wing-box structure under ten-dimensional(all-dependent)random inputs.

关键词： forward uncertainty quantification(UQ) generalized polynomial chaos expansion(GPcE) static reanalysis method static condensation substructuring

Harnessing exosomes for targeted therapy: strategy and application

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Biomaterials Translational 2024年第1期5卷 46-58页

作者： Ren X. Xu R. Xu c. Su j. Organoid Research center Institute of Translational Medicine Shanghai University Shanghai China National center for Translational Medicine (Shanghai) SHU Branch Shanghai University Shanghai China Department of Microbial Pathogenesis Yale University School of Medicine New Haven CT United States Department of Biomedical Engineering City University of Hong Kong Hong Kong Special Administrative Region China Department of Orthopedic Xinhua Hospital Shanghai Jiao Tong University School of Medicine Shanghai China

Exosomes, nanoscopic extracellular vesicles produced by cells, are pivotal in mediating intracellular communication by transporting nucleic acids, proteins, lipids, and other bioactive molecules, thereby influencing physiological and pathological states. Their endogenous origin and inherent diversity confer distinct advantages over synthetic vehicles like liposomes and nanoparticles in diagnostic and therapeutic applications. Despite their potential, the clinical utility of exosomes is hampered by challenges such as limited storage stability, yield, purity, and targeting efficiency. This review focuses on exosomes as targeted therapeutic agents, examining their biogenesis, classification, isolation, and characterisation, while also addressing the current limitations in yield, purity, and targeting. We delve into the literature to propose optimisation strategies that can enhance their therapeutic efficacy and accelerate the translation of exosome-based therapies into clinical practice. © 2024, chinese Medical Multimedia Press co Ltd. All rights reserved.

关键词： biomedical engineering exosomes modification nanotechnology targeted therapy

DAMPING BEHAVIOR OF ULTRAFINE-GRAINED PURE ALUMINUM L2 AND THE DAMPING MEcHANISM

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维普期刊数据库

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Acta Metallurgica Sinica(English Letters) 2006年第3期19卷 223-227页

作者： Z.M. Zhang c.j. Xu j.c. Wang H.Z. Liu School of Materials Science ＆ Engineering Xi＇an University of Technology Xi＇an 710048 Ghina State Key Laboratory of Solidification Processing Northwestern Polytechnical University Xi＇an 710072 Ghina

Ultrafine-grained pure aluminum L2 with a mean grain size of 1.01μm was produced by equal channel angular pressing （EcAP） and annealing at 150℃ for 2h. Damping behavior of the alloy was measured using a dynamic mechanical thermal analyzer. The alloy had an excellent damping capacity Q^-1 with the ambient value being 9.8×10^-3 at 1.0Hz when the strain amplitude was 2.0×10^-5. The damping behavior of the alloy showed a non-linear damping variation tendency, that is, with an increase in temperature and a decrease of frequency, the damping capacity of the alloy increased. The damping capacity increased with the strain amplitude when the strain amplitude was less than 4.6×10^-5. When the strain amplitude was higher than 4.6×10^-5, the damping capacity became a constant and independent of strain amplitude. The high damping capacity was attributed to dislocation unpinning and a drag of dislocation on pinning points.

关键词： EcAP ultrafine grain damping capacity aluminum alloy

Generation of Eco-Friendly and Disease-Resistant channel catfish(Ictalurus punctatus)Harboring the Alligator cathelicidin Gene via cRISPR/cas9 Engineering

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Engineering 2024年第8期39卷 273-286页

作者： jinhai Wang Baofeng Su De Xing Timothy j.Bruce Shangjia Li Logan Bern Mei Shang Andrew johnson Rhoda Mae c.Simora Michael coogan Darshika U.Hettiarachchi Wenwen Wang Tasnuba Hasin j.c.b Al-Armanazi cuiyu Lu Rex A.Dunham School of Fisheries Aquacultureand Aquatic SciencesAuburn UniversityAuburnAL 36849USA

As a precise and versatile tool for genome manipulation,the clustered regularly interspaced short palindromic repeats(cRISPR)/cRISPR-associated protein 9(cas9)platform holds promise for modifying fish traits of *** the aim of reducing transgene introgression and controlling reproduction,upscaled disease resistance and reproductive intervention in catfish species have been studied to lower the potential environmental risks of the introgression of escapees as transgenic *** advantage of the cRISPR/cas9-mediated system,we succeeded in integrating the cathelicidin gene(As-cath)from an alligator(Alligator sinensis)into the target luteinizing hormone(lh)locus of channel catfish(Ictalurus punctatus)using two delivery systems assisted by double-stranded DNA(dsDNA)and single-stranded oligodeoxynucleotides(ssODNs),*** this study,high knock in(KI)efficiency(22.38%,64/286)but low ontarget events was achieved using the ssODN strategy,whereas adopting a dsDNA as the donor template led to an efficient on-target KI(10.80%,23/213).The on-target KI of As-cath was instrumental in establishing the lh knockout(LH^(–)_As-cath^(+))catfish line,which displayed heightened disease resistance and reduced fecundity compared with the wild-type(WT)sibling ***,administration of human chorionic gonadotropin(HcG)and luteinizing hormone-releasing hormone analogue(LHRHa)can restore the reproduction of the transgenic fish ***,we replaced the lh gene with an alligator cathelicidin transgene and then administered hormone therapy to move towards complete reproductive control of diseaseresistant transgenic catfish in an environmentally responsible *** strategy not only effectively improves consumer-valued traits but also guards against unwanted introgression,providing a breakthrough in aquaculture genetics to confine fish reproduction and prevent the establishment of transgenic or domestic genotypes in the natural environment.

关键词： Genome editing ssODN dsDNA Antimicrobial peptide Reproductive confinement Aquaculture