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Exper.m.ntal Study of Endwall and Tip Clearance Flows in a Two- Dimensional Turbine rotor Blade Cascade - Effect of Incidence Angle

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Journal of Thermal Science 2000年第1期9卷 63-76页

作者： m. Govardhan B.H.L. Gowda r.m. wankhade Depar.m.nt of mechanical Engineering Indian Institute of Technology Madras Chennai 600036 India Department of Applied Mechanics Indian Institute of Technology Madras Chennai 600 036 India(Department of Mechanical Engineering Indian Institute of T

Exper.m.ntal investigations were carried out on a two-dimensional cascade fitted with a 120° deflection rotor blades to study the effect of incidence angle on the endwall flow in the presence of tip clearance. A total of five incidence angles, namely: -10°，-10° -5°, 0°, 5° ， 10° were chosen and for each incidence angle, the exper.m.nts were conducted for five tip clearance values at a constant space -chord ratio of 0.79. The results are presented in the form of contours of static pressure coefficient on the endwall and the blade tip surface. In addition, the variation of static pressure coefficient ahead of the blade leading edge and fr.m.the pressure surface to the suction surface at various axial stations, and discharge coefficient gi different axial stations are presented. The results indicate that the adverse pressure gradient upstream of the leading edge is reduced as tip clearance is increased. The contours of static pressure coefficient on the endwall indicate a deep low-pressure trough near the suction surface in comparison to the normal trough for zero clearance. Loading also increases as incidence changes fr.m.the negative to positive values. Due to area contraction caused by the tip separation vortex, the fluid moving towards the tip gap fr.m.the pressure side is accelerated. Downstream of the tip separation vortex, the endwall pressure increases due to flow mixing. The maximum value of discharge coefficient increases and the point at which maximum value occurs shifts towards leading edge when incidence is changed fr.m.-10° to 10°.

关键词： endwall blade tip surface tip clearance incidence angle tip separation vortex discharge coefficient.

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Nuclear radiation shielding effectiveness and corrosion behavior of some steel alloys for nuclear reactor systems

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Defence Technology（防务技术） 2019年第4期15卷 621-628页

作者： m.m. Sadawy r.m. El Shazly mining and Petroleum Engineering Depar.m.nt Al-Azhar University Nasr City Cairo 11371 Egypt Physics Depar.m.nt Faculty of Science Al-Azhar University Nasr City Cairo 11884 Egypt

Different types of nuclear par.m.ters and corrosion behavior were deduced for carbon steel(AISI 1018),austenitic(304 SS),and duplex(2507 SS)stainless steel *** types of neutron energies as well as nine gamma ray energy lines(121.78-1407.92 keV)were used to evaluate the macroscopic neutron cross-sections(∑,cm^-1)and mass attenuation coefficients[σ,cm^2·g^-1)of gamma ray *** corrosion behavior was investigated using different electrochemical *** results showed that the stainless-steel alloys had a good attitude than that of carbon steel alloy for neutron and gamma ray par.m.ters,especially the duplex stainless *** calculated values of mass attenuation coefficient using WinXcom computer progr.m.Version 3.1),exhibited a very good agreement with the exper.m.ntal values of that ***,the results indicated that duplex stainless-steel exhibited corrosion resistance higher than 304 SS and AISI 1018 steel alloys.

关键词： Steel alloys macroscopic cross-section mass attenuation coefficient Passive film Pitting

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EXACT EVALUATIONS OF FINITE TrIGONOmETrIC SUmS BY SAmPLING THEOr.m.

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Acta mathematica Scientia 2011年第2期31卷 408-418页

作者： m.H. Annaby r.m. Asharabi Depar.m.nt of mathematics Faculty of Science Cairo University Depar.m.nt of mathematics Faculty of Education Al-MahweetSana'a University

We use the sampling representations associated with Sturm-Liouville difference operators to derive generalized integral-valued trigonometric sums. This extends the known results where zeros of Chebyshev polynomials of the first kind are involved to the use of the eigenvalues of difference operators, which leads to new identities. In these identities Bernoulli＇s numbers play a role similar to that of Euler＇s in the old ones. Our technique differs fr.m.that of Byrne-Smith （1997） and Berndt-Yeap （2002）.

关键词： Trigonometric sums difference equations sampling theorem

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GIS-based analysis of fault patterns in urban areas： A case study of Irkutsk city, russia

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Geoscience Frontiers 2016年第2期7卷 287-294页

作者： r.m. Lobatskaya I.P. Strelchenko Irkutsk research Technological University Irkutsk Russia

The capabilities of GIS in modeling fault patterns are explored for Irkutsk city in East Siberia with implications for ground stability. The neotectonic structure of the area is visualized in three dimension （3D） taking into account fault dips, using the ArcGIS, Globalmapper and Paradigm Geophysical packages. The study area is divided into blocks of different size classes according to the length-based ranks of the bounding faults, which are of five classes distinguished with the equal interval method. The blocks show different deformation patterns, with different densities and strikes of crossing and bounding faults. The data are statistically processed using GIS to estimate the deformation degrees of blocks in arbitrary units per square kilometer using the attributes of rank and crossing/bounding position of faults and the size of blocks. The deformation degrees are then compared with available estimates of ground stability measured as a score of points corresponding to destabilizing factors. Although the comparison generally confirms some linkage between the deformation degree of blocks and their ground stability, the correlation is intricate and ambiguous. In order to enhance the advantages of GIS in building and analyzing 3D models of fault patterns for estimating ground stability and mitigating geological hazards, it is expected in the future to proceed fr.m.the reported initial step of visualization to more advanced analysis.

关键词： GIS 3D modeling Fault pattern Faults Blocks Ground stability

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Heterogeneity of mature oligodendrocytes in the central nervous system

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Neural regeneration research 2025年第5期20卷 1336-1349页

作者： Chao Weng Adam m.r.Groh moein Yaqubi Qiao-Ling Cui Jo Anne Stratton G.r.Wayne moore Jack P.Antel Neuroimmunology Unit Montreal Neurological Institute-HospitalDepartment of Neurology and NeurosurgeryMcGill UniversityMontrealQCCanada Depar.m.nt of Neurology Renmin Hospital of Wuhan UniversityWuhanHubei ProvinceChina

mature oligodendrocytes form myelin sheaths that are crucial for the insulation of axons and efficient signal transmission in the central nervous *** evidence has challenged the classical view of the functionally static mature oligodendrocyte and revealed a gamut of dynamic functions such as the ability to modulate neuronal circuitry and provide metabolic support to *** the recognition of potential heterogeneity in mature oligodendrocyte function,a comprehensive summary of mature oligodendrocyte diversity is *** delve into early 20th-century studies by robertson and río-Hortega that laid the foundation for the modern identification of regional and morphological heterogeneity in mature ***,recent morphologic and functional studies call into question the long-assumed homogeneity of mature oligodendrocyte function through the identification of distinct subtypes with varying myelination ***,modern molecular investigations,employing techniques such as single cell/nucleus rNA sequencing,consistently unveil at least six mature oligodendrocyte subpopulations in the human central nervous system that are highly transcriptomically diverse and vary with central nervous system *** and disease related mature oligodendrocyte variation denotes the impact of pathological conditions such as multiple sclerosis,Alzheimer's disease,and psychiatric ***,caution is warranted when subclassifying mature oligodendrocytes because of the simplification needed to make conclusions about cell identity fr.m.temporally confined *** studies leveraging advanced techniques like spatial transcriptomics and single-cell proteomics pr.m.se a more nuanced understanding of mature oligodendrocyte *** research avenues that precisely evaluate mature oligodendrocyte heterogeneity with care to understand the mitigating influence of species,sex,central nervous system region,age,and disease,

关键词： aging central nervous system diseases electron microscopy heterogeneity immunohistochemistry myelin sheath natural history neuroglia oligodendroglia single-cell gene expression analysis

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Guava extract (Psidium guajava) alters the labelling of blood constituents with technetium-99m

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Journal of Zhejiang University-Science B(Biomedicine & Biotechnology) 2006年第6期7卷 429-435页

作者： ABrEU P.r.C. ALmEIDA m.C. BErNArDO r.m. BErNArDO L.C. BrITO L.C. GArCIA E.A.C. FONSECA A.S. BErNArDO-FILHO m. Depar.m.nt of Biophysics and Biometry Institute of Biology Roberto Alcantara Gomes University of Estate of Rio de Janeiro Rio de Janeiro 20551030 Brazil Depar.m.nt of Physiology Biological Sciences and Health Center Federal University of Sergipe So Cristóvo Sergipe 49100000 Brazil Depar.m.nt of Pharmacology and Psychobiology Institute of Biology Roberto Alcantara Gomes University of Estate of Rio de Janeiro Rio de Janeiro 20551030 Brazil

Psidium guajava (guava) leaf is a phytotherapic used in folk medicine to treat gastrointestinal and respiratory dis-turbances and is used as anti-inflammatory medicine. In nuclear.m.dicine, blood constituents (BC) are labelled with techne-tium-99m (99mTc) and used to image procedures. However, data have demonstrated that synthetic or natural drugs could modify the labelling of BC with 99mTc. The aim of this work was to evaluate the effects of aqueous extract of guava leaves on the labelling of BC with 99mTc. Blood samples of Wistar rats were incubated with different concentrations of guava extract and labelled with 99mTc after the percentage of incorporated radioactivity (%ATI) in BC was determined. The results suggest that aqueous guava extract could present antioxidant action and/or alters the membrane structures involved in ion transport into cells, thus decreasing the radiolabelling of BC with 99mTc. The data showed significant (Pration of ATI in BC fr.m.blood incubated with guava extract.

关键词： Antioxidant Blood constituents Psidium guajava Technetium-99m

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Getting physical with medical education:Exercise based virtual anatomy review classes for.m.dical students

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World Journal of methodology 2025年第1期15卷 20-25页

作者： Nadeesha r Samarasinghe Taniya S Nagpal michele L Barbeau Charys m martin Division of General Surgery Faculty of MedicineUniversity of British ColumbiaVancouver V6T 1Z3BCCanada Faculty of Kinesiology Sport and RecreationUniversity of AlbertaEdmonton T6G 2R3ABCanada Anatomy and Cell Biology University of Western OntarioLondon N6A 3K7ONCanada Depar.m.nt of Anatomy and Cell Biology Schulich School of Medicine and DentistryThe University of Western OntarioLondon N6A 3K7ONCanada

The benefits of regular physical activity are well ***,few studies have examined the effectiveness of integrating physical activity(PA)into curricula within a post-secondary *** investigate the incorporation of PA into medical curriculum,we developed a series of optional exercise-based review sessions designed to reinforce musculoskeletal(mSK)anatomy course *** synchronous sessions were co-taught by a group fitness instructor and an anatomy *** fitness instructor would lead students through both strength and yoga style exercises,while the anatomy instructor asked questions about relevant anatomical structures related to course material previously *** the sessions,participants were asked to evaluate the classes on their self-reported exam preparedness in improving mSK anatomy knowledge,PA levels,and mental *** participants completed surveys;a majority agreed that the classes increased understanding of mSK concepts(90.0%)and activity levels(97.7%).many(70.0%)felt that the classes helped reduce *** majority of respondents(90.0%)agreed that the classes contributed to increased feelings of social ***,medical students saw benefit in PA based interventions to supplement mSK course *** with increasing activity levels and pr.m.ting health behaviours,integrating PA into medical curriculum may improve comprehension of learning material,alleviate stress and foster social connectivity among medical students.

关键词： medical education musculoskeletal Anatomy Exercise Online learning

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Nonlinear forced vibration in a subcritical regime of a porous functionally graded pipe conveying fluid with a retaining clip

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Applied mathematics and mechanics(English Edition) 2025年第1期46卷 101-122页

作者： m.GHOLAmI m.EFTEKHArI Depar.m.nt of mechanical Engineering Shahid Bahonar University of Kerman

This study examines the nonlinear behaviors of a clamped-clamped porous pipe made of a functionally graded material(FGm) that conveys fluids and is equipped with a retaining clip, focusing on pr.m.ry resonance and subcritical dynamics. The nonlinear governing equations for the FGm pipe are derived by the extended Hamilton's principle, and subsequently discretized through the application of the Galerkin *** direct method of multi-scales is then used to solve the derived equations. A thorough analysis of various par.m.ters, including the clip stiffness, the power-law index, the porosity, and the clip location, is conducted to gain a comprehensive understanding of the system's nonlinear dynamics. Through the analysis of the first natural frequency, the study highlights the influence of the flow velocity and the clip stiffness, while the comparisons with metallic pipes emphasize the role of FGm composition. The examination of the forced response curves reveals saddle-node bifurcations and their dependence on par.m.ters such as the detuning par.m.ter and the power-law index, offering valuable insights into the system's nonlinear resonant behavior. Furthermore, the frequency-response curves illustrate the hardening nonlinearities influenced by factors such as the porosity and the clip stiffness, revealing nuanced effects on the system response and resonance characteristics. This comprehensive analysis enhances the understanding of nonlinear behaviors in FGm porous pipes with a retaining clip, providing key insights for practical engineering applications in system design and optimization.

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Charaeterizability of the Group ~2D_p(3) by its Order Components,Where p≥5 is a Pr.m. Number Not of the Form 2~m+1

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Acta mathematica Sinica,English Series 2008年第7期24卷 1117-1126页

作者： m.r.DArAFSHEH School of mathematics College of ScienceUniversity of TehranTehranIran

The author will prove that the group ^2Dp（3） can be uniquely determined by its order components, where p ≠ 2^m ＋ 1 is a pr.m. number, p ≥ 5. more precisely, if OC（G） denotes the set of order components of G, we will prove OC（G） = OC（^2Dp（3）） if and only if G is isomorphic to ^2Dp（3）. A main consequence of our result is the validity of Thompson＇s conjecture for the groups under consideration.

关键词： pr.m. graph order component linear group

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Preparation, Characterization, Biological Activity and 3D molecular.m.deling of mn（Ⅱ）, Co（Ⅱ）, Ni（Ⅱ）, Cu（Ⅱ）, Pd（Ⅱ） and ru（Ⅲ） Complexes of Some Sulfadrug Schiff Bases

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Chinese Journal of Chemistry 2012年第4期30卷 881-890页

作者： EL-Ghamry,H.A. Sakai,K. masaoka,S. EI-Baradie,K.Y Issa,r.m. Chemistry Depar.m.nt Faculty of ScienceTanta UniversityTantaEgypt Chemistry Depar.m.nt Faculty of ScienceKyushu UniversityFukuokaJapan Institute for.m.lecular Science National Institutes of Natural SciencesJapan

mn（Ⅱ）, Co（Ⅱ）, Ni（Ⅱ）, Cu（Ⅱ）, Pd（Ⅱ） and ru（Ⅲ） complexes of Schiff bases derived fr.m.the condensation of sulfaguanidine with 2,4-dihydroxy benzaldehyde （HL1）, 2-hydroxy-l-naphthaldehyde （HL2） and salicylaldehyde （HL3） have been synthesized. The structures of the prepared metal complexes were proposed based on elemental analysis, molar conductance, thermal analysis （TGA, DSC and DTG）, magnetic susceptibility measur.m.nts and spectroscopic techniques （Ir, UV-Vis, and ESr）. In all complexes, the ligand bonds to the metal ion through the azomethine nitrogen and a-hydroxy oxygen atoms. The structures of Pd（Ⅱ） complex 8 and ru（Ⅲ） complex 9 were found to be polynuclear. Two kinds of stereochemical geometries; distorted tetrahedral and distorted square py- r.m.dal, have been realized for the Cu（Ⅱ） complexes based on the results of UV-Vis, magnetic susceptibility and ESr spectra whereas octahedral geometry was predicted for Co（Ⅱ）, mn（Ⅱ） and ru（Ⅲ） complexes. Ni（Ⅱ） com- plexes were predicted to be square planar and tetrahedral and Pd（Ⅱ） complexes were found to be square planar. The antimicrobial activity of the ligands and their.m.tal complexes was also investigated against the gr.m.positive bac- teria Staphylococcus aures and Bacillus subtilis and gr.m.negative bacteria, Escherichia coli and Pesudomonas aeruginosa, by using the agar dilution method. Chlor.m.henicol was used as standard compound. The obtained data revealed that the metal complexes are more or less, active than the parent ligand and standard. The X-ray crys- tal structure of HL3 has been also reported.

关键词： sulfaguanidine transition metal complexes spectral studies biological activity crystal structure mo- lecular.m.deling

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