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Effects of External stresses on the Carbide Precipitation in Bainite Transformation

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Journal of Beijing Institute of Technology 2005年第2期14卷 192-195页

作者：苏铁健 denis s GAUTIER E school of Materials science and Engineering Beijing Institute of Technology Beijing100081 China Laboratory of Metal Materials science and Technology Ecole des Mines de Nancy Nancy Cedex F-54042 France Laboratory

TEM observation of carbide precipitates in bainite has been carried out for steel 40CMD8. specimens transformed at 350 ℃ and 450 ℃ without external stress contain respectively the lower and the upper bainite. No fundamental change in carbide precipitation is observed in specimen transformed at 350 ℃ under stress of 128 MPa. The very fine cementite is found precipitated within the upper bainite plates in specimen transformed at 450 ℃ under stress of 144 MPa, which can be explained as the result of the difficulty of carbon diffusing out of the massive ferrite plate within a much shortened transformation time due to the external stress. For all the specimens examined, Bagaryatskii orientation relationship is found existing between the carbides and ferrite matrix.

关键词： bainite transmission electron microscopy carbide phase transformation

Pitfalls and promises of bile duct alternatives:There is plenty of room in the regenerative surgery

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World Journal of Gastroenterology 2023年第30期29卷 4701-4705页

作者： Ilya D Klabukov denis s Baranovskii Peter V shegay Andrey D Kaprin Department of Regenerative Medicine National Medical Research Radiological Center of the Ministry of Health of the Russian FederationObninsk 249036Russia Center for Innovative Radiological and Regenerative Technologies National Medical Research Radiological Center of the Ministry of Health of the Russian FederationObninsk 249036Russia

Current abdominal surgery has several approaches for biliary ***,the creation of functional and clinically applicable bile duct substitutes still represents an unmet *** the paper by Miyazawa and colleagues,approaches to the creation of bile duct alternatives were summarized,and the reasons for the lack of development in this area were *** history of bile duct surgery since the nineteenth century was also traced,leading to the conclusion that the use of bioabsorbable materials holds promise for the creation of bile duct substitutes in the *** suggest three ideas that may stimulate progress in the field of bile duct substitute ***,a systematic analysis of the causative factors leading to failure or success in the creation of bile duct substitutes may help to develop more effective ***,the regeneration of a bile duct is delicately balanced between epithelialization and subsequent submucosal maturation within limited time frames,which may be more apparent when using quantitative models to estimate ***,the utilization of the organism’s endogenous regeneration abilities may enhance the creation of bile duct *** are convinced that an interdisciplinary approach,including quantitative methods,machine learning,and deep retrospective analysis of the causes that led to success and failure in studies on the creation of bile duct substitutes,holds great ***,more attention should be directed towards the balance of epithelialization and submucosal maturation rates,as well as induced *** ideas deserve further investigation to pave the way for bile duct restoration with physiologically relevant outcomes.

关键词： Bile duct alternative Bile duct substitute Regenerative medicine Regene rative surgery Theoretical surgery Quantitative human physiology

studies of ultrasonic dehydration efficiency

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Journal of Zhejiang University-science A(Applied Physics & Engineering) 2011年第4期12卷 247-254页

作者： Vladimir N. KHMELEV Andrey V. sHALUNOV Roman V. BARsUKOV denis s. ABRAMENKO Andrey N. LEBEDEV Biysk Technological Institute (Branch) Altai state Technical University

The aim of this investigation was to define the effectiveness of non-contact drying using ultrasonic vibrations. Disk radiators were used for carrying out experiments, and a special drying chamber was designed to provide resonant amplification of ultrasonic vibrations (from 130 to 150 dB). Drying of ginseng and other vegetables demonstrated that the application of ultrasonic vibrations reduced power inputs by 20% in comparison with convective drying. It also led to a decrease of 6% in final moisture content, if the duration of drying was constant. The level of intensification of ultrasonic drying was high (up to 50 g for 1 kg of drying material), which helped to lower the temperature of the drying agent and improve the quality of the dried products.

关键词： Drying Ultrasound Vibration system Drying chamber Processing (treatment) of agricultural products

Ilizarov bone transport combined with the Masquelet technique for bone defects of various etiologies (preliminary results)

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World Journal of Orthopedics 2022年第3期13卷 278-288页

作者： Dmitry Y Borzunov sergey N Kolchin denis s Mokhovikov Tatiana A Malkova Department of Taumatology and Orthopedics Ural State Medical UniversityEkaterinburg 620109Russia Orthopaedic Department 4 Ilizarov National Medical Research Center for Traumatology and OrthopaedicsKurgan 640014Russia Department of Medical Information and Analysis Ilizarov National Medical Research Center for Traumatology and OrthopaedicsKurgan 640014Russia

BACKGROUND The Ilizarov bone transport(IBT)and the Masquelet induced membrane technique(IMT)have specific merits and shortcomings,but numerous studies have shown their efficacy in the management of extensive long-bone defects of various etiologies,including congenital *** their strong benefits seems a promising strategy to enhance bone regeneration and reduce the risk of refractures in the management of post-traumatic and congenital defects and nonunion that failed to respond to other *** To combine IBT and IMT for the management of severe tibial defects and pseudarthrosis,and present preliminary results of this technological *** seven adults with post-traumatic tibial defects(subgroup A)and nine children(subgroup B)with congenital pseudarthrosis of the tibia(CPT)were treated with the combination of IMT and IBT after the failure of previous *** mean number of previous surgeries was 2.0±0.2 in subgroup A and 3.3±0.7 in subgroup *** 1 included Ilizarov frame placement and spacer introduction into the defect to generate the induced membrane which remained in the interfragmental gap after spacer *** 2 was an osteotomy and bone transport of the fragment through the tunnel in the induced membrane,its compression and docking for consolidation without *** outcomes were retrospectively studied after a mean follow-up of 20.8±2.7 mo in subgroup A and 25.3±2.3 mo in subgroup *** The“true defect”after resection was 13.3±1.7%in subgroup A and 31.0±3.0%in subgroup B relative to the contralateral *** completion of treatment,defects were filled by 75.4±10.6%and 34.6±4.2%,*** duration of external fixation was 397±9.2 and 270.1±16.3 d,including spacer retention time of 42.4±4.5 and 55.8±6.6 d,in subgroups A and B,*** infection was not *** complications were several cases of pin-tract infection and regenerate deformity in both *** regener

关键词： Ilizarov bone transport Induced membrane technique Post-traumatic tibial defect Congenital pseudarthrosis of the tibia Distraction osteogenesis Regeneration

Kriging-boosted CR modeling for prompt infill drilling optimization

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Petroleum 2024年第1期10卷 39-48页

作者： Elizaveta s.Gladchenko Anna E.Gubanova denis M.Orlov Dmitry A.Koroteev skolkovo Institute of science and Technology Russian Federation Digital Petroleum LLC Russian Federation

The capacitance-resistance model(CRM) has been a useful physics-based tool for obtaining production forecasts for decades. However, the model's limitations make it difficult to work with real field cases,where a lot of various events happen. such events often include new well commissioning(NWC). We introduce a workflow that combines CRM concepts and kriging into a single tool to handle these types of events during history matching. Moreover, it can be used for selecting a new well placement during infill drilling. To make the workflow even more versatile, an improved version of CRM was used. It takes into account wells shut-ins and performed workovers by additional adjustment of the model coefficients. By preliminary re-weighing and interpolating these coefficients using kriging, the coefficients for potential wells can be determined. The approach was validated using both synthetic and real datasets, from which the cases of putting new wells into operation were selected. The workflow allows a fast assessment of future well performance with a minimal set of reservoir data. This way, a lot of well placement scenarios can be considered, and the best ones could be chosen for more detailed studies.

关键词： Capacitance-resistance model (CRM) Field development optimization Infill drilling Interwell connectivity Kriging New well commissioning (NWC)

Residence time distribution of wood chips in a semi-industrial multiple hearth furnace using RFID tracers Author links open overlay panel

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Particuology 2024年第8期91卷 268-279页

作者： Elie Lacombe Muriel Marchand Capucine Dupont denis Maréchal Thierry Melkior Univ Grenoble Alpes CEALITENDTCHLaboratoire Réacteurs et ProcédésF-38000GrenobleFrance IHE Delft Department of Water Supply Sanitation and Environmental EngineeringDelftthe Netherlands John Cockerill SeraingBelgium

In continuous biomass torrefaction plants,the products'yields,composition and homogeneity highly depend on the residence time of particles.A characterization of particle residence time distribution(RTD)was therefore carried out in an industrial-scale multiple hearth furnace on poplar wood chips using radio frequency identification *** effects of operating conditions,namely,mass flow rate of biomass,shaft speed of the rabbling system and interdental length on the RTD were *** increase of shaft speed and mass flow rate reduces particles’mean residence *** the length between two successive teeth also increases the bed *** biomass accumulation(also called“bulldozing”)was observed during several *** phenomenon is favored by a high mass flow rate of resources,a small interdental length between the teeth and a low shaft *** measurements were compared to the axial dispersion *** all tests,the Peclet number is ranging between 20 and 62,indicating that the multiple hearth furnace cannot be modelled as an ideal plug flow reactor.

关键词： Biomass Multiple hearth furnace Residence time distribution RFID

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外加应力对贝氏体相变组织形貌的影响

材料科学与工艺 2005年第3期13卷 251-253页

作者：苏铁健李树奎张朝晖 AEBY-GAUTIER E denis s BRIEN V 北京理工大学材料科学与工程学院 Ecole des Mines de Nancy Parc de Saurupt Nancy 54042 China

为揭示贝氏体相变机制及外加应力对它的影响,采用透射电镜研究了140MPa的外加拉应力对中碳低合金钢35MV7的450°C等温贝氏体相变组织形貌的影响.研究发现,由于外加应力的存在,贝氏体相变基元及其组成的铁素体条的尺寸变得非常粗大并形... 详细信息

为揭示贝氏体相变机制及外加应力对它的影响,采用透射电镜研究了140MPa的外加拉应力对中碳低合金钢35MV7的450°C等温贝氏体相变组织形貌的影响.研究发现,由于外加应力的存在,贝氏体相变基元及其组成的铁素体条的尺寸变得非常粗大并形成多样的变态.这种尺寸的变化是由于外加应力产生额外的相变驱动力,使相变基元块可以克服更大的弹性应变能而长成更大的体积.

关键词：贝氏体相变外加应力组织形貌中碳低合金钢透射电镜研究相变基元相变驱动力弹性应变能相变机制应力产生拉应力铁素体尺寸

Comparison of ERA5 turbulent fluxes at the air-sea interface with measurements from a wave-following platform

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Atmospheric and Oceanic science Letters 2024年第3期17卷 32-36页

作者： said Benjeddou denis Bourras Christopher Luneau Aix Marseille Universite National Center for Scientific ResearchMediterranean Institute of OceanographyMarseilleFrance Observatory of the sciences of the Universe Pytheas Institute National Center for Scientific ResearchMarseilleFrance

Turbulent fluxes at the air-sea interface were estimated with data collected in 2011-2020 with a low-profile platform named OCARINA during eight experiments in five regions:2011,2015,and 2016 in the Iroise sea;2012 in the tropical Atlantic;2014 in the Chilie-Peru upwelling;2017 and 2018 in the Mediterranean sea,and 2018 and 2020 in *** observations were carried out with moderate winds(2-10 m s^(-1))and average wave heights of 1.5 *** this study,the authors used the fluxes calculated by the bulk method using OCARINA-sampled data as the *** data can validate the fluxes estimated from ERAs reanalysis *** OCARINA and ERA5 data were taken *** do this,the authors established an algorithm to extract the OCARINA data as closely as possible to the reanalysis data in time and *** measurements of the OCARINA platform can conclude on the relevance of the widely used reanalysis data.

关键词： Ocarina ECMWF ERA5 Turbulent fluxes Louis formulation

Correcting distortions of thin-walled machined parts by machine hammer peening

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Chinese Journal of Aeronautics 2024年第6期37卷 439-453页

作者： Aitor MADARIAGA Mikel CUEsTA Gorka ORTIZ-DE-ZARATE Eneko sAENZ-DE-ARGANDONA denis sORIANO Michael B.PRIME Pedro Jose ARRAZOLA Department of Materials University of ManchesterOxford RoadManchester M139PLUnited Kingdom Mechanical and Industrial Production Department Faculty of EngineeringMondragon UnibertsitateaArrasate 20500Spain Los Alamos National Laboratory Los AlamosNew MexicoUSA

Thin-walled aerostructural components frequently get distorted after the machining *** to correct distortions or eventually rejecting parts significantly increases the *** paper proposes a new approach to correct distortions in thin-walled components by strategically applying hammer peening on target surfaces of a machined *** alloy 7475-T7351 was chosen for this *** study was divided in two ***,the residual stresses(Rs)induced by four different pneumatic hammer peening conditions(modifying the stepover distance and initial offset)were characterised in a test coupon,and one of the conditions was selected for the next *** the second stage,a FEM model was used to predict distortions caused by machining in a representative ***,the Rs induced by hammer peening were included in an FEM model to define two hammer peening strategies(varying the coverage area)to analyse the capability to reduce *** workpieces were machined and then treated with the simulated hammer peening strategies for experimental *** in the test coupon showed that pneumatic hammer peening can generate high compressive Rs(-50 to350 MPa)up to 800 lm depth,with their magnitude increasing with a reduced stepover *** of hammer peening over 4% of the surface of the representative workpiece reduced the machininginduced distortions by 37%,and a coverage area of 100% led to and overcorrection by a factor of *** confirms that hammer peening can be strategically applied(in target areas and changing the percentage of coverage)to correct low or severe distortions.

关键词： Aeronautics Machining,Hammer Peening Aluminium alloy Distortions Residual stress