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Acta Mechanica Sinica 2019年第6期35卷 1241-1256页

作者： Z.Y.liu t.l.Jiang l.Wang h.l.Dai Department of Mechanics Huazhong University of Science and TechnologyWuhan 430074China hubei Key laboratory for Engineering Structural Analysis and Safety Assessment Wuhan 430074China

Pipe-in-pipe(PIP)structures are widely used in offshore oil and gas pipelines to settle thermal insulation issues.A PIP structure system usually consists of two concentric pipes and one softer layer for thermal insulation *** total response of the system is related to the dynamics of both pipes and the interactions between these two concentric *** the current work,a theoretical model for flow-induced vibrations of a PIP structure system is proposed and analyzed in the presence of an internal axial flow and an external cross *** interactions between the two pipes are modeled by a linear distributed damper,a linear distributed spring and a nonlinear distributed spring along the pipe *** unsteady hydrodynamic forces due to cross flow are modeled by two distributed van der Pol wake *** nonlinear partial differential equations for the two pipes and the wake are further discretized by the aid of Galerkin’s technique,resulting in a set of ordinary differential *** ordinary differential equations are further numeri cally solved by using a fourth-order Runge-Kutta integration *** portraits,bifurcation diagrams,an Argand diagram and oscillation shape diagrams are plotted,showing the existence of a lock-in phenomenon and figure-of-eight *** PIP system subjected to cross flow displays some interesting dynamical behaviors different from that of a single-pipe structure.

关键词： Cantilevered PIP structure theoretical model Flow-induced vibration Cross flow Internal flow

Al-Ca-Fe合金中Al_(10)CaFe_(2)化合物的形成与表征

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transactions of Nonferrous Metals Society of China 2024年第2期34卷 361-377页

作者： N.A.BElOV t.K.AKOPYAN E.A.NAUMOVA V.V.DOROShENKO t.A.SVIRIDOVA N.O.KOROtKOVA National University of Science and technology MISIS 4 Leninsky pr.Moscow 119049Russia Baikov Institute of Metallurgy and Materials Science 49 Leninsky pr.Moscow 119991Russia

采用热力学计算和实验技术研究铝角的Al-Ca-Fe体系相图,包括液相面投影图和凝固反应。结果表明,与铝固溶体(Al)平衡的不是Al_(3)Fe相,而是一种组成符合化学式Al_(10)CaFe_(2)的三元化合物。通过包晶转变l+Al_(3)Fe→(Al)+Al_(10)CaFe_(2... 详细信息

采用热力学计算和实验技术研究铝角的Al-Ca-Fe体系相图,包括液相面投影图和凝固反应。结果表明,与铝固溶体(Al)平衡的不是Al_(3)Fe相,而是一种组成符合化学式Al_(10)CaFe_(2)的三元化合物。通过包晶转变l+Al_(3)Fe→(Al)+Al_(10)CaFe_(2)(638℃,3.3%Ca和0.5%Fe,摩尔分数)发生从二元化合物到三元化合物的转变。与针状Al_(3)Fe相夹杂物不同,三元化合物的初晶和共晶具有致密的形貌。使用第一性原理计算和X射线衍射分析确定三元化合物Al_(10)CaFe_(2)的晶格结构。此外,近共晶合金Al-6%Ca-1%Fe(质量分数)在500~600℃退火后具有细晶组织,过量相的总体积分数约为25%。因此,Al-Ca-Fe体系可用于制造新的铝基复合合金。

关键词： Al-Ca合金金属间化合物相图相变显微组织铝基复合材料

Generation of millijoule-level sub-5 fs violet laser pulses

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high Power laser Science and Engineering 2024年第2期12卷 33-40页

作者： Xinhua Xie Yi hung Yunpei Deng Adrian l.Cavalieri Andrius Baltuška Steven l.Johnson SwissFEl Paul Scherrer InstituteVilligen PSISwitzerland Photonics Institute Technische Universität WienViennaAustria Institute of Applied Physics University of BernBernSwitzerland Institute for Quantum Electronics Physics DepartmentETH ZurichZurichSwitzerland

We demonstrate the generation,spectral broadening and post-compression of second harmonic pulses using a thin beta barium borate(BBO)crystal on a fused-silica substrate as the nonlinear interaction *** combining second harmonic generation in the BBO crystal with self-phase modulation in the fused-silica substrate,we efficiently generate millijoule-level broadband violet pulses from a single optical *** second harmonic spectrum covers a range from long wave ultraviolet(down to 310 nm)to visible(up to 550 nm)with a bandwidth of 65 ***,we compress the second harmonic beam to a duration of 4.8 fs with a pulse energy of 0.64 mJ(5 fs with a pulse energy of 1.05 mJ)using chirped *** all-solid free-space apparatus is compact,robust and pulse energy scalable,making it highly advantageous for generating intense second harmonic pulses from near-infrared femtosecond lasers in the sub-5 fs regime.

关键词： post-compression second harmonic generation self-phase modulation supercontinuum generation

Microstructure of Nitrided Aluminum Alloys Using an Electron-Beam-Excited-Plasma (EBEP)

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材料热处理学报 2004年第5期25卷 349-353页

作者： l.liu A.Yamamoto t.hishida h.Shoyama t.hara h.tsubakino GraduateSchool UniversityofHyogo2167ShoshaHimeji671-2201Japan FaultyofEngineering ToyotaTechnologicalInstituteNagoya468-8511Japan

Nitriding of surface of aluminum alloys was carried out with using an electron-beam-excited-plasma (EBEP) technique. the EBEP is sustained by electron impact ionization with energetic electron beam. two kinds of substrates, aluminum alloys AA5052 and AA5083, were exposed to the down flow of EBEP source at 843 K for 45min. the specimens were characterized with respect to following properties: crystallographic structure (XRD), morphology (SEM) and the cross sectional microstructures of the nitrided layer was observed using a scanning electron microscopy (SEM). there are some A12O3 particles on the surface of the nitrided AA5052 and AA5083. the A1N layers were formed on the substrates with the thickness of 4.5 fi m for AA5052 and 0.5 /z m for AA5083 . A relatively uniform nitrided surface layer composed of A1N can be observed on the AA5052 substrate. the grains size near the interfaces between the substrate and A1N layer were smaller than that near the surface. On the surface of A1N layer, the concentration of nitrogen was high and in the middle of A1N layer it had a constant concentration like the aluminum and the concentration was decreased with approaching to the interface. On the surface of nitrided AA5083, a uniform A1N layer was not formed as the reason for the high nitriding temperature.

关键词：显微结构铝合金渗氮 EBEP

Evaluation of the Quality of life of Patients Suffering from Chronic Rhinosinusitis in a hospital Setting in Kinshasa

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International Journal of Otolaryngology and head & Neck Surgery 2024年第1期13卷 41-52页

作者： hilaire K. Kalala Patricia K. Kakobo honoré N. Yalombe lievin K. Mvita léon N. Muamba Dieudonné t. Nyembue Otorhinolaryngology Service University of Kinshasa Democratic Republic of Congo Imaging Department University of Kinshasa Democratic Republic of Congo Ophthalmology Service University of Kinshasa Democratic Republic of Congo

Background and objective: Chronic rhinosinusitis (CRS), a common disease worldwide, has a major impact on patients’ quality of life (Qol). In recent years, the measurement of health-related Qol has made it possible to assess the patient’s state of health, the severity of the CRS and the treatment. the aim of this study was to assess the Qol of patients with CRS in a hospital setting in Kinshasa. Methods: this was a cross-sectional analytical study conducted from June 2020 to May 2021 in the ENt service of the Kinshasa University hospital and the Monkole hospital Center. the study involved 113 patients aged at least 18 years, whose QOl was compared with that of a control group consisting of 100 non-patients. QOl was assessed using the Sino-Nasal Outcome test (SNOt-22) Questionnaire. Results: the mean age of the patients was 41.0 years (18 - 74 years) and that of the controls was 39.1 years (19 - 77 years). More than half of the participants were university graduates. the median SNOt-22 score was 44 (14 - 78) in patients and 7 (1 - 40) in controls. Compared with subjects without CRS, patients with CRS had significantly higher scores in all four domains of the SNOt-22. Around 9 out of 10 patients had a severely impaired Qol compared with 2 out of 10 controls. Considering mildly impaired Qol, we found that in the otological and sleep domains, scores were not significantly different between patients and controls. In the case of severely impaired Qol, however, only the otological domain showed a non-significant difference in scores between the two groups. Conclusion: CRS is a real public health problem in our environment and significantly alters the Qol of patients suffering from it, with repercussions on their professional productivity;hence the need for better management.

关键词： Chronic Rhinosinusitis Quality of life SNOt-22 ENt Kinshasa

DPY19l3 promotes vasculogenicmimicry by its C-mannosyltransferase activity

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Oncology Research 2024年第4期32卷 607-614页

作者： hASSAN BAYDOUN YUJI KAtO hIROKI KAMO ANNA hÜSCh hAYAtO MIZUtA RYOtA KAWAhARA SIRO SIMIZU Department of Applied Chemistry Faculty of Science and TechnologyKeio UniversityYokohama223-8522Japan Department of Pharmacy and Biochemistry Faculty of ScienceUniversity of TübingenTübingen72074Germany

C-mannosylation is a post-translational modification that occurs intracellularly in the endoplasmic *** humans,biosynthesis of C-mannosylation in proteins containing thrombospondin type 1 repeat is catalyzed by the DPY19 family;nonetheless,biological functions of protein C-mannosylation are not yet fully understood,especially in tumor *** mimicry(VM)is the formation of fluid-conducting channels by highly invasive and genetically deregulated tumor cells,enabling the tumors to form matrix-embedded vasculogenic structures,containing plasma and blood cells to meet the metabolic demands of rapidly growing *** this study,we focused on DPY19l3,a C-mannosyltransferase,and aimed to unravel its role in *** of DPY19l3 inhibited the formation of VM in ht1080 human fibrosarcoma ***-expression of wild-type DPY19l3 recovered VM formation;however,DPY19l3 isoform2,an enzymatic activity-defect mutant,did not restore it,suggesting that the C-mannosyltransferase activity of DPY19l3 is crucial to its ***,the knockdown of DPY19l3 in MDA-MB-231 breast cancer cells hindered its network formation ***,our findings suggest that DPY19l3 is required for VM formation and stipulate the relevance of C-mannosylation in oncogenesis.

关键词： C-mannosylation Vasculogenic mimicry DPY19l3

A nanobody-based blocking enzyme-linked immunosorbent assay for detecting antibodies against pseudorabies virus glycoprotein E

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Journal of Integrative Agriculture 2024年第4期23卷 1354-1368页

作者： huanhuan lü Pinpin Ji Siyu liu Ziwei Zhang lei Wang Yani Sun Baoyuan liu lizhen Wang Qin Zhao Department of Preventive Veterinary Medicine College of Veterinary MedicineNorthwest A&F University/Shaanxi Scientific Observing and Experimental Station of Veterinary Pharmacology and Diagnostic TechnologyMinistry of Agriculture and Rural AffairsYangling 712100China

Pseudorabies(PR)is an acute infectious disease of pigs caused by the PR virus(PRV)and results in great economic losses to the pig industry *** glycoprotein E(gE)-based enzyme-linked immunosorbent assay(ElISA)has been used to distinguish gE-deleted vaccine-immunized pigs from wild-type virus-infected pigs to eradicate PR in some *** has the advantages of small size and easy genetic engineering and has been a promising diagnostic ***,there were few reports about developing nanobody-based ElISA for detecting anti-PRV-gE *** the present study,the recombinant PRV-gE was expressed with a bacterial system and used to immunize the Bactrian ***,two nanobodies against PRV-gE were screened from the immunized camel by phage display ***,two nanobody-hRP fusion proteins were expressed with hEK293t *** PRV-gE-Nb36-hRP fusion protein was selected as the probe for developing the blocking ElISA(bElISA)to detect anti-PRV-gE *** optimizing the conditions of bElISA,the amount of coated antigen was 200 ng per well,and dilutions of the fusion protein and tested pig sera were separately 1:320 and 1:*** cut-off value of bElISA was 24.20%,and the sensitivity and specificity were 96.43 and 92.63%,*** detecting 233 clinical pig sera with the developed bElISA and a commercial kit,the results showed that the coincidence rate of two assays was 93.99%.Additionallly,epitope mapping showed that PRV-gE-Nb36 recognized a conserved conformational epitope in different reference PRV ***,great stability and low-cost nanobody-based bElISA for detecting anti-PRV-gE antibodies were *** bElISA could be used for monitoring and eradicating PR.

关键词： nanobody nanobody-hRP blocking ElISA PRV-gE antibody

the ability of biostimulants and copper-containing fungicide to protect cotton against chilling stress

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Journal of Cotton Research 2024年第3期7卷 223-230页

作者： ERGIN Nurgül KUlAN Engin Gokhan hARMANCI Pinar KAYA Mehmet Demir Faculty of Agriculture and Natural Sciences Department of Field CropsBilecik Seyh Edebali UniversityBilecikTürkiye Faculty of Agriculture Department of Field CropsEskisehir Osmangazi UniversityEskisehirTürkiye

Background Cotton(Gossypium hirsutum l.),adapted to tropical and subtropical regions of the world,is highly sensitive to low temperatures throughout its life *** objective of this study was to evaluate the mitigating effects of different doses of animal-derived(0.25%,0.50%,and 1.00% Isabion■),seaweed-based(0.165%,0.330%,and 0.660% Proton■)biostimulants,as well as a copper(Cu)-containing fungicide application,on cotton cultivar lazer seedlings at the four true leaves(V4)*** plants were exposed to a low temperature of 5℃for 48 h,and the changes in morphological(seedling fresh and dry weight,plant height,and stem diameter)and physiological parameters(leaf temperature,chlorophyll content,relative water content,electrolyte leakage,and relative injury)were *** the results revealed that chilling stress reduced plant growth,while biostimulants helped protect the plants and overcome the adverse effects of *** chilling stress,there was a considerable reduction in seedling fresh weight(SFW),seedling dry weight(SDW),plant height(Ph),stem diameter(SD),leaf temperature(lt),and relative water content(RWC).Cotton seedlings treated with the animal-derived biostimulants showed significantly enhanced SFW,SDW,Ph,SD,lt,chlorophyll content(Chl),electrolyte leakage(El),and relative injury(RI),although there were no positive changes in *** significant differences in the morphological traits were observed among the doses of seaweed *** SDW,Ph,El,and RI,the best results were obtained with the application of a fungicide containing *** these results show the efficiency of the biostimulant and fungicide treatments in mitigating low-temperature stress in cotton *** a copper-containing fungicide to cotton seedlings helped to counteract the negative effects of low-temperature stress and to protect the plants from damage by maintaining electrolyte *** the biostimulant applications,all levels of animal-derive

关键词： Gossypium hirsutum l. Cold stress Electrolyte leakage

MRI征象预测极早期至中期肝细胞肝癌切除术后生存期

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国际医学放射学杂志 2024年第4期 497-498页

作者： h.Y.Jiang Y.Qin h.Wei t.Y.Zheng t.Yang Y.A.Wu 程昊

摘要目的对比增强MRI可以为肝细胞肝癌（hCC）病人提供个体化的预后信息，研究旨在探讨MRI征象对早期无复发生存（≤2年，E-RFS）、晚期无复发生存（>2年，l-RFS）

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Influence of austenization temperature on the erosion behavior of austempered ductile irons

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Journal of University of Science and technology Beijing 2008年第1期15卷 29-33页

作者： l.C. Chang l C. hsui l.h. Chen S.t. lui Department of Mechanical Engineering Technology and Science Institute of Northern Taiwan Taipei 112 China Talpei Department of Materials Science and Engineering Cheng-Kung University Talnan 800 China Taipei

the erosion behavior of austempered ductile irons austenized at different temperatures was studied. the results indicate that the erosion rate well correlates with the mechanical properties. At high impact angles, increasing ductility and mechanical energy density results in decreasing erosion rate, whereas increasing hardness reduces the erosion rate at low impact angles. 2008 University of Science and technology Beijing. All rights reserved.

关键词： austempered ductile iron erosion mechanical properties austenization