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Coarse to Fine: The Role of Severe Plastic Deformation in Advancing Titanium-Based me.ical implants - A Comprehensive Review

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Journal of Wuhan University of Technology(Materials Science) 2025年第1期40卷 295-306页

作者： Dragana R Mihajlović Bojan i međo ivana Lj Cvijović-Alagić Veljko R Djokić Faculty of Technology and metallurgy University of BelgradeKarnegijeva 411120 BelgradeSerbia Vinča institute of Nuclear Sci-ences-National institute of the Republic of Serbia University of Belgrade11001BeogradSerbia innovation Centre of the Faculty of Technology and metallurgy Karnegijeva 411120 BelgradeSerbia

This paper describes severe plastic deformation(SPD)procedures,which are utilized to form an ultrafine-grained structure in metallic *** the SPD process,a solid material sample is subjected to very high loads without a significant change in sample *** the present work,the high-pressure torsion(HPT)process,as one of the SPD techniques,which achieves a high degree of deformation and ensures refinement of the microstructure,will be discussed in more *** that grain size control is accepted as a method to obtain materials with desired characteristics,an overview of the properties of ultrafine-grained titanium-based biomaterials to be used in me.icine is ***,particular attention is dedicated to the influences of HPT process parameters,primarily hydrostatic pressure,and number of revolutions during torsion,on the grain size and physical and mechanical characteristics(modulus of elasticity,microhardness,and tensile properties),corrosion resistance,and biocompatibility of the titanium-based biomaterials.A review of the literature indicates that titanium-based materials obtained by the SPD process show improved mechanical and physical properties without losing biocompatibility and corrosion resistance,which suggests that these methods of obtaining implants are something that should be further developed in the future.

关键词： high-pressure torsion process ultrafine-grained titanium-based materials electrochemical anodization physical properties mechanical properties

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Shrinkage of magnetosphere observed by TC-1 satellite during the high-speed solar wind stream

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Science China(Technological Sciences) 2008年第10期51卷 1695-1703页

作者： H. Rme.i. DANDOURAS C. M. CARR Centre d'Etude Spatiale des Rayonnements BP 4346 31028 Toulouse cedex 4 France The Blackett Laboratory Imperial College London SW7 2BZ UK

During the interval 06:14―07:30 UT on August 24, 2005, since the Earth’s magneto- pause was suddenly compressed by the persistent high-speed solar wind stream with the southward component of the interplanetary magnetic field (iMF), the magnetopause moved inward for about 3.1 RE. meanwhile, TC-1 satellite shifted from northern plasma sheet to the northern lobe/mantle region, although it kept inward flying during the interval 06:00―07:30UT. The shift of TC-1 from the plasma sheet to the lobe/mantle is caused by the simultaneous inward displacements of the plasma sheet and near-Earth lobe/mantle region, and their inward movement velocity is larger than the inward motion velocity of TC-1. The joint inward dis-placements of the magnetopause, the lobe/mantle region and the plasma sheet indicate that the whole magnetosphere shrinks inward due to the magnetospheric compression by the high-speed solar wind stream, and the magnetospheric ions are attached to the magnetic field lines (i.e. ‘frozen’ in magnetic field) and move inward in the shrinking process of magnetosphere. The large shrinkage of magne-tosphere indicates that the near-Earth magnetotail compression caused by the strong solar wind dynamic pressure is much larger than its thickening caused by the southward component of the iMF, and the locations of magnetospheric regions with different plasmas vary remarkably with the variation of the solar wind dynamic pressure.

关键词： solar wind dynamic pressure shrinkage of magnetosphere storm sudden commencement substorm

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Superconducting parameter determination for (Co0.5Zn0.5Fe2O4)x/Cu0.5Tl0.5-1223 composite

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Journal of Advanced Ceramics 2016年第3期5卷 210-218页

作者： M.me.BARAKAT N.AL-SAYYED R.AWAD A.i.ABOU-ALY Physics Department Faculty of Science Alexandria University Alexandria Egypt Physics Department Faculty of Science Beirut Arab University Beirut Lebanon

The addition of magnetic Co0.5Zn0.5Fe2O4 nanoparticles to the superconducting Cu0.5Tl0.5-1223 phase has been used to investigate the electrical resistivity behavior of the composite above the superconducting transition temperature Tc. This was studied according to the opening of spin gap and fluctuation conductivity. The results indicated that the pseudogap temperature (T*) and superconducting fluctuation temperature (Tscf) change by increasing the addition of Co0.5Zn0.5Fe2O4 nanoparticles. it was found that T* is related to hole carrier concentration P and it also depends on the antiferromagnetic fluctuation affected by magnetic nanoparticles. The excess-conductivity analysis showed four different fluctuation regions started from high temperature up to Tc, and they were denoted by short wave (sw), two-dimensional (2D), three-dimensional (3D), and critical (cr) fluctuations. The crossover temperature between 3D and 2D (T3D-2D) in the mean field region was decreased by increasing the addition of Co0.5Zn0.5Fe2O4 nanoparticles, in accordance with the decrease in Tscf with x. The coherence length at 0 K along c-axis ξc(0), effective layer thickness of the 2D system d, and inter-layer coupling strength J were estimated as a function of Co0.5Zn0.5Fe2O4 nanoparticle addition. Moreover, the thermodynamics, lower and upper critical magnetic fields, as well as critical current density have been calculated from the Ginzburg number NG. it was found that the low concentration of Co0.5Zn0.5Fe2O4 nanoparticles up to x = 0.08 wt% improves the superconducting parameters of Cu0.5Tl0.5-1223 phase. On the contrary, these parameters were deteriorated f

关键词： Co0.5Zn0.5Fe2O4 nanoparticles Cu0.5Tl0.5-1223 phase pseudogap temperature fluctuation conductivity

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Cenozoic ultrahigh-temperature metamorphism in pelitic granulites from the Mogok metamorphic belt, Myanmar

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Science China Earth Sciences 2021年第11期64卷 1873-1892页

作者： Si CHEN Yi CHEN Yibing Li Bin SU Qinghua ZHANG me me AUNG Kyaing SEiN State Key Laboratory of Lithospheric Evolution and Institutions of Earth ScienceInstitute of Geology and GeophysicsChinese Academy of SciencesBeijing 100029China Chinese Academy of Sciences Center for Excellence in Tibetan Plateau Earth Sciences Beijing 100101China University of Chinese Academy of Sciences Beijing 100049China Geology Department Myitkyina UniversityKachin StateMyitkyina 01012Myanmar Myanmar Geosciences Society Hlaing University CampusYangon 11062Myanmar

Ultrahigh-temperature(UHT)metamorphism is critical for understanding the most extreme thermal evolution of continental ***,UHT metamorphism predominantly occurred in the Precambrian and is rarely observed in the modern ***,we report the discovery of~25 Ma UHT granulites from the Mogok metamorphic belt(MMB)in Myanmar via a combined study of petrology and *** studied pelitic granulites well preserve a peak mineral assemblage of garnet+sillimanite+plagioclase(antiperthite)+K-feldspar+quartz+Ti-rich biotite+rutile+***(P)-temperature(T)pseudosections and conventional geothermobarometry data only constrain the P-T conditions of the peak stage toigh Zr contents in the matrix rutile(3005–4308 ppm)and high Ti contents(up to 9.2 wt% TiO_(2))in the biotite demonstrate that the Mogok granulites may have experienced UHT *** Zr-in-rutile thermometer and X_(Grs) isopleth in the pseudosections yield peak P-T conditions of~12 kbar and>900°*** situ SiMS and LAiCP-MS U-Pb dating and trace element analyses show that both metamorphic zircon cores and rims have flat heavy rare earth element(HREE)patterns with negative Eu *** metamorphic zircon rims show the lowest HREE contents and yield ^(206)Pb/^(238)U ages of 24.9±0.5 and 25.4±0.6 Ma,respectively,representing the timing of UHT *** results indicate that the central MMB underwent~25 Ma UHT metamorphism,which is possibly induced by continental rifting along the thinned orogenic *** data,as well as reported Cenozoic UHT events,further suggest that UHT metamorphism can be produced in the modern plate tectonic regime by lithospheric extension.

关键词： Mogok metamorphic belt Ultrahigh-temperature metamorphism Pelitic granulites Zr-in-rutile thermometry Zircon chronology

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Magnetoresistivity studies for BiPb-2223 phase added by BaSnO3 nanoparticles

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Journal of Advanced Ceramics 2017年第2期6卷 100-109页

作者： Mai me.BARAKAT Khulud HABANJAR Department of Physics Faculty of Science Alexandria University Alexandria Egypt Department of Physics Faculty of Science Beirut Arab University Beirut Lebanon

Co-precipitation method and conventional solid-state reaction technique were used to synthesize BaSnO3 nanoparticles and (BaSnO3)x/Bi1.6Pb0.4Sr2Ca2Cu3O10+δ (0≤x≤ 1.50w t％) samples,respectively.X-ray powder diffraction (XRD),scanning electron microscopy (SEM),and electrical resistivity data were used to characterize BiPb-2223 phase added by BaSnO3 *** relative volume fraction and superconducting transition temperature Tc of BiPb-2223 phase were enhanced by increasing BaSnO3 addition up to 0.50 wt％.These parameters were decreased with further increase of *** resistive transition broadening under different applied DC magnetic fields (0.29-4.40kG) was analyzed through thermally activated flux creep (TAFC) model and Ambegaokar-Halperin (AH) *** of the derived flux pinning energy U,critical current density Jc (0) estimated from AH parameter C(B),and upper critical magnetic field Bc2 (0),were recorded by adding BaSnO3 nanoparticles up to 0.50 wt％,beyond which these parameters were *** magnetic field dependence of the flux pinning energy and critical current density decreased as a power-law relation,which indicated the single junction sensitivity between the superconducting grains to the applied magnetic ***,the increase in the applied magnetic field did not affect the electronic thermal conductivity Ke above the superconducting transition temperature and suppressed it below Tc.

关键词： BiPb-2223 BaSnO3 nanoparticles flux pinning energy critical current density

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Dependency-aware unequal erasure protection codes

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2006年第z1期7卷 27-33页

作者： BOUABDALLAH Amine LACAN Jérme Laboratory for Analysis and Architecture of Systems Toulouse 31077 France Applied Mathematics and Computer Science DepartmentENSICAToulouse 31056France Telecommunications for Space and AeronauticToulouse 31000France

Classical unequal erasure protection schemes split data to be protected into classes which are encoded independently. The unequal protection scheme presented in this paper is based on an erasure code which encodes all the data together according to the existing dependencies. A simple algorithm generates dynamically the generator matrix of the erasure code according to the packets streams structure, i.e., the dependencies between the packets, and the rate of the code. This proposed erasure code was applied to a packetized MPEG4 stream transmitted over a packet erasure channel and compared with other classical protection schemes in terms of PSNR and MOS. it is shown that the proposed code allows keeping a high video quality-level in a larger packet loss rate range than the other protection schemes.

关键词： Data dependencies integration Unequal erasure protection (UEP) Lossy networks Reliable video transmissions MPEG4 video codec

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A unified electrical model based on experimental data to describe electrical transport in carbon nanotube-based materials

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Nano Research 2020年第6期13卷 1764-1779页

作者： Yoann Dini Jérôme Faure-Vincent Jean Dijon Univ.Grenoble-Alpes CEALITENDTNMF-38000GrenobleFrance Univ.Grenoble-Alpes CEACNRSIRIGSyMMESF-38000GrenobleFrance

Understanding the electrical transport in carbon nanotube(CNT)materials is one key to reach very high electrical *** CNT material resistivity(ρ(T))as function of the temperature are fully apprehended by their reduced activation W(T)=dln(ρ)/dln(T)*** to now,no model accurately fits W(T)curves,thus preventing from precisely describing the CNT material electrical *** present a new electrical transport model that perfectly fits all W(T)curves found in the literature and in our own *** material resistivities are modeled byρ(T)=ρ0(T^−α+M(1+βTγT^2)).Our model has few enough parameters(α,M,β,γ)to relate them to the CNT *** 70 K,we experimentally show that CNT material resistivity follows the Luttinger Liquid theory justifying the T^−αterm in our *** 70 K,the polynomial part becomes dominant and depends on the two different CNT fabrication techniques which lead to two very different yarn *** yarns made from floating catalyst chemical vapor deposition CNTs,the polynomial is explained by the percolation of metallic CNT ***,the polynomial of yarns spun from CNT arrays is explained by the electrical transport in CNT bundles which are the basic building blocks of this type of yarns.

关键词： carbon nanotube carbon-based materials electrical conductivity electrical transport model Luttinger Liquid

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Hepatic steatosis and fibrosis: Non-invasive assessment

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World Journal of Gastroenterology 2016年第45期22卷 9880-9897页

作者： Rustam N Karanjia Mary me Crossey i Jane Cox Haddy KS Fye Ramou Njie Robert D Goldin Simon D Taylor-Robinson Liver Unit Division of Digestive Health Department of Surgery and Cancer Imperial College London St Mary’s Campus London W2 1NY United Kingdom institute of Hepatology London Foundation for Liver Research 111 Coldharbour Lane London SE5 9NT United Kingdom Faculty of Life Sciences and me.icine King’s College London London SE5 9NT United Kingdom MRC Gambia Atlantic Road Fajara The Gambia

Chronic liver disease is a major cause of morbidity and mortality worldwide and usually develops over many years, as a result of chronic inflammation and scarring, resulting in end-stage liver disease and its complications. The progression of disease is characterised by ongoing inflammation and consequent fibrosis, although hepatic steatosis is increasingly being recognised as an important pathological feature of disease, rather than being simply an innocent bystander. However, the current gold standard method of quantifying and staging liver disease, histological analysis by liver biopsy, has several limitations and can have associated morbidity and even mortality. Therefore, there is a clear need for safe and noninvasive assessment modalities to determine hepatic steatosis, inflammation and fibrosis. This review covers key mechanisms and the importance of fibrosis and steatosis in the progression of liver disease. We address non-invasive imaging and blood biomarker assessments that can be used as an alternative to information gained on liver biopsy.

关键词： Hepatic steatosis Fibrosis Non-invasive assessment Blood biomarker Ultrasound

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impact loads generated by tandem cavitation bubble on solid wall

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Journal of Hydrodynamics 2022年第3期34卷 467-482页

作者： Nyo me Thet Naing Jaehyun Park Seung-Ho Hyun Rho-Taek Jung School of Naval Architecture and Ocean Engineering University of UlsanUlsanKorea School of Electrical Engineering University of UlsanUlsanKorea Foundation for industry Cooperation University of UlsanUlsanKorea

Experiments on two cavitation bubbles,which are generated at the same.instant,with three different sizes near solid wall are conducted and their impulses on the boundary are registered by polyvinylidene fluoride(PVDF)*** to being near the boundary,bubble interactions and deformed features are in contrast with those in infinite fluid *** this paper,five morphologies of bubble deformation during growth and collapse phases are observed by high-speed *** profiles are strongly influenced by inter-bubble distance(η),stand-off distance from boundary(γ),and bubble size *** of photographs coupled with sensor measurements enabled qualitative investigation of two bubble interactions on the *** sensor data acquisition,it is confirmed that lower bigger bubble with upper smaller bubble configuration produces highest impulses on the boundary compared with other vertical arrangements of the tandem cavitation bubble employed in this study.

关键词： Two bubbles spark-generated bubble impulse polyvinylidene fluoride(PVDF)

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Surveys on magnetospheric plasmas based on the Double Star Project (DSP) exploration

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Science China(Technological Sciences) 2008年第10期51卷 1639-1647页

作者： C. P. ESCOUBET C. M. CARR H. Rme A. FAZAKERLEY H. LAAKSO i. DANDOURAS M. DUNLOP ESA/ESTEC SCI-SH Keplerlaan 1 2200 AG Noordwijk The Netherlands imperial College of Science Technology and Medicine London SW7 2BZ United Kingdom CESR BP4346 31028 Toulouse Cedex 4 France Mullard Space Science Laboratory Univ. College London Dorking Surrey RH5 6NT United Kingdom imperial College of Science Technology and Medicine London SW7 2BZ United Kingdom Rutherford Appleton Laboratory Didcot Oxon OX11 0QX United Kingdom

The equatorial and polar satellites of the Double Star Project (DSP) were launched successfully on December 29, 2003 and July 25, 2004, respectively, and both of them are operating smoothly. The DSP provides a good opportunity for investigat-ing the structure of the magnetosphere. Based on the DSP data collected during 2004, we have surveyed the distribution of the magnetic fields and plasmas in the magnetosphere. it is found that: (1) Near the Earth’s equatorial plane within geo-centric distances of less than 7 RE, the Earth’s magnetic field is dipolar. in the vi-cinity of the magnetopause, the magnetic field is enhanced by a factor of about 1.5, and on the nightside, the magnetic field can vary significantly from the Earth’s di-pole field, likely caused by the presence of the near-Earth tail current sheet. (2) in the day-side magnetosheath, the electron and ion densities are usually both in the range of 10―30 cm?3; the ion and electron temperatures are usually about 200 and 50 eV, respectively. The flow pattern is usually smooth, with a low velocity in the subsolar region and with significantly higher velocities in the dawn and dusk flanks. (3) in the region between the magnetopause and plasmasphere the density is low, approximately 0.5―5 cm?3, and the temperature is high, about 1―10 keV for ions and 0.1―5 keV for electrons. The ion temperature has an apparent anisotropy, with the ratio of the perpendicular and parallel temperatures being about 1.0―1.3 for the night- and dusk-side magnetosphere and about 1.3―2.0 for the day- and dawn-side magnetosphere. There is an evident sunward convection of about 50 km/s in the magnetosphere. On the dawn side, the flow becomes somewhat turbulent, and in the vicinity of the night-noon me.idian plane, the convection is rather slow. (4) The high-energy electrons with energies higher than 2 meV are mainly located in the regions with 3 ize of the high-energy electrons area varies with time, it may expand and shrink

关键词： Earth’s magnetosphere space exploration geomagnetic field space plasmas

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