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THERMAL STABILITY OF NON-EQUILIBRIUS MICROSTRUCTURE IN MICROALLOYEd STEEL dURING REHEATING

Acta Metallurgica Sinica(English Letters) 2007年第5期20卷 313-326页

作者： H.B. Wu H.T. Jiang S.W. Yang d. Tang X.L. He National Engineering Research Center for Advanced Rolling Technology University of Science and Technology Beijing Beijing 100083 China dept. of Materials Physics University of Science and Technology Beijing Beijing 100083 China

Cooled in water after isothermal relaxation of deformed austenite for different times, an Nb-bearing microalloyed steel always exhibits synthetic microstructures, in which bainitic ferrite ,dominates. dislocation configurations and distributions of strain induced precipitates inside bainitic ferrite of samples relaxed for different times were distinct. When compared with the austenite model steel, which maintained fcc structure even at room temperature, the strain induced precipitates were not found in the sample without relaxation whereas these were distributed outside dislocations in sample relaxed for 1000s. Most of the strain induced precipitates distribute along dislocations and pin dislocations in sample relaxed for appropriate time. After bainitic transformation, the dislocations formed in deformed austenite remain to be pinned by the precipitates. When these samples were reheated to and held at 650 or 700℃, the non-equilibrloas microstructures tended to evolve into equilibrioas ones. The sample relaxed for 60s displayed the highest thermo-stability, whereas microstructure evolution was the quickest in the sample relaxed for 1000s even though it was the softest prior to reheating. dislocations inside laths got rid of pinning of precipitates, and their polygonization became the precursor to the evolution of microstructures during reheated and held, followed by gradual disappearance of lath boundaries caused by dislocation climbing. Finally, recrystallization occurred and polygonal ferrite appeared. By hardness measurement, it was found that softening is not a single process occurring during reheated, in which hardness fluctuates with time. There were two peaks in the hardness-time curve of each sample having undergone relaxation, while single peak occured in the curve of the sample not being relaxed. These results indicated that the thermo-stability of microstructures was determined by their history of formation to a considerable degree.

关键词： bainite reheating strain induced precipitate pinning microstructures evolution

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AdVANCEd QUALITY CONCEPTS ANd COMPOSITE RELIABILITY THROUGH STATISTICALPROCESS CONTROL

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Acta Metallurgica Sinica(English Letters) 1997年第3期10卷 263-269页

作者： d. Evans (CCLRC, Rutherford Appleton Laboratory, Chilton, Oxon. OX14 2HQ U.K.) Rutherford Appleton Lab Oxon United Kingdom

The physical properties of thermosetting resins and resin based composites may be influenced by changes in any one of the mang formulating or process related variables involved in their manufacture. When resins and composite materials are required to perform in aggressive environments, reliable and predicable performance is essential and therefore these materials must be prepared and tested in accorkance with a strictquality plan. This paper outlines the elements of statistical process control (S.P.C.)as it may be applied to non-metallic materials and discusses the concept of Capability Index (Cp).

关键词： physical property composite process control cryogenic application

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device-based neuromodulation for cardiovascular diseases and patient’s age

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Journal of Geriatric Cardiology 2022年第11期19卷 876-893页

作者： Evgeny N Mikhaylov Nigar Z Gasimova Natalia N Belyaeva Heber Ivan Condori Leandro Aleksandr d Vakhrushev Evgeny V Shlyakhto Almazov National Medical Research Centre Saint-PetersburgRussia

The autonomic nervous system plays an important role in the pathogenesis of cardiovascular *** aging,autonomic activity changes,and this impacts the physiological reactions to internal and external *** sympathetic and parasympathetic responses seem to decline,reflecting functional and structural changes in nervous *** some investigators suggested that both the sympathetic and parasympathetic activities were suppressed,others found that only the parasympathetic activity was suppressed while the sympathetic activity *** addition,cardiac innervation progressively diminishes with ***,one may suggest that neuromodulation interventions may have different effects,and older age groups can express an attenuated *** article aims to discuss the effect of device-based neuromodulation in different cardiovascular diseases,depending on the patient’s ***,we cover renal denervation,pulmonary artery denervation,baroreceptor activation therapy,vagus nerve stimulation,spinal cord stimulation,ganglionated plexi ablation for the management of arterial and pulmonary hypertension,heart failure,angina and *** results of many clinical studies appeared to be *** view of the low rate of positive findings in clinical studies incorporating neuromodulation approaches,we suggest the underestimation of advanced age as a potential contributing factor to poorer *** of outcomes between different age groups in clinical trials may shed more light on the true effects of neuromodulation when neutral/ambiguous results are obtained.

关键词： stimulation cardiovascular diseases

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Tilted global solar irradiance in Bahrain:an experimental study

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Clean Energy 2024年第2期8卷 27-34页

作者： N.Vasilikos C.Georgantopoulou H.Alajaimi S.H.Almajed M.Ahmed d.Mathioulakis School of Mechanical Engineering Bahrain PolytechnicIsa TownPO Box 33349Kingdom of Bahrain School of Mechanical Engineering National Technical University of AthensHeroon Polytechniou 7 StZografos 15773AthensGreece

In the present work,tilted global solar irradiance data are presented and analysed,measured for a period of 1 year on the campus of Bahrain Polytechnic,Kingdom of Bahrain,from both a fixed photovoltaic panel and a moving one via a two-axis solar *** fixed panel faces south with an angle of 26°with respect to the horizontal,coinciding with the local geographical *** second panel is moved by two motors,controlled by a global positioning system and suitable software so that the Sun’s rays are perpendicular to the panel surface.A pyranometer is installed on each panel,recording the tilted global solar irradiance,stored by using a data *** analysis of the data obtained shows a 33%solar energy gain on an annual basis for the moving panel(2780 versus 2088 kWh/m^(2) on the fixed panel).More importantly,in June,when the energy demand in Bahrain is elevated due to the increased residential cooling loads,the solar energy received by the moving panel is 54.7%higher compared with that of the fixed *** a percentage basis,the increase in solar energy from the moving panel is profound in the early morning and late evening ***,the reduction in the solar energy received by the fixed panel from May to June does not appear in the moving panel because of the adjustable orientation of the *** the year,the mean daily solar power varies between 0.37 and 0.56 kW/m^(2) for the fixed panel,and 0.45 and 0.70 kW/m^(2) for the moving *** winter,solar energy fluctuations are elevated due to erratic weather conditions that present a peak standard deviation of 28%of the corresponding *** data presented are useful for potential solar investments in Gulf countries.

关键词： tilted solar irradiance renewable energy solar tracking photovoltaic Gulf Cooperation Council Countries

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Liquid flow in scaffold derived from natural source:experimental observations and biological outcome

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Regenerative Biomaterials 2022年第1期9卷 480-489页

作者： Elisabetta Salerno Giulia Orlandi Claudio Ongaro Alessandro d’Adamo Andrea Ruffini Gianluca Carnevale Barbara Zardin Jessika Bertacchini diego Angeli CNR-NANO S3 Research Center on Nanostructures and Biosystems at Surfaces Modena I-41125Italy department of Sciences and Methods for Engineering University of Modena and Reggio EmiliaReggio Emilia 42122Italy department of Surgery MedicineDentistry and Morphological Sciences with Interest in TransplantOncology and Regenerative MedicineUniversity of Modena and Reggio EmiliaModena 41125Italy dIEF-Engineering department“Enzo Ferrari” University of Modena and Reggio EmiliaModena 41125Italy Institute of Science and Technology for Ceramics(ISTEC) National Research Council(CNR)Faenza 48018Italy

This study investigates the biological effects on a 3d scaffold based on hydroxyapatite cultured with MC3T3 osteoblasts in response to flow-induced shear stress(FSS).The scaffold adopted here(B-HA)derives from the biomorphic transformation of natural wood and its peculiar channel geometry mimics the porous structure of the *** the point of view of fluid dynamics,B-HA can be considered a network of micro-channels,intrinsically offering the advantages of a microfluidic *** work,for the first time,offers a description of the fluid dynamic properties of the B-HA scaffold,which are strongly connected to its *** features are necessary to determine the FSS ranges to be applied during in vitro studies to get physiologically relevant *** selected ranges of FSS promoted the elongation of the attached cells along the flow direction and early osteogenic cell *** data confirmed the ability of B-HA to promote the differentiation process along osteogenic ***,such a bioactive and naturally derived scaffold can be considered as a promising tool for bone regeneration applications.

关键词： fluid shear stress flow resistance hydroxyapatite 3d scaffold

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Guild composition and habitat use of voles in 2 forest landscapes in south-eastern Norway

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Integrative Zoology 2011年第4期6卷 299-310页

作者： Lucrezia GORINI John d.C.LINNELL Luigi BOITANI Ulrike HAUPTMANN Morten OddEN Per WEGGE Erlend B.NILSEN department of Animal and Human Biology Sapienza University of RomeRomeItaly Faculty of Applied Ecology and Agricultural Sciences Hedmark University CollegeCampus EvenstadKoppangNorway Norwegian Institute for Nature Research TrondheimNorway department of Ecology and Natural Resource Management Norwegian University of Life SciencesÅsNorway

It is widely believed that intensive forestry has influenced small mammal population dynamics,and thereby the entire mammalian community in Fennoscandian boreal *** nature of these impacts on the different species is subject to *** live-trapped voles between 2006 and 2009 in 2 commercially harvested forests in south-eastern *** investigated the variation in vole abundance among habitat types(*** forest and clear-cut)and the hypothesis that graminivorous species such as field voles(Microtus agrestis L.)benefit from clear-cuts at the expense of forest dwellers(*** bank vole,Myodes glareolus Schreb.),using fine-scale descriptors of the ground *** could not find support for the hypothesis that field voles show a preference for clear-cuts,and their overall abundance was low,while bank voles were the dominant species in all habitat types,including clear-cuts in the peak and pre-peak *** found a positive association between bank vole abundance and bilberry(Vaccinium myrtillus L.)availability rather than a specific habitat *** field vole density in clear-cuts might be due to variation in local productivity and ground vegetation as well as to large variation in the species temporal *** latter is particularly associated with the widespread decline of field voles in *** has the potential to negatively affect bank vole population dynamics because of the negative effect on bilberry development.

关键词： bank vole bilberry clear-cut field vole forestry

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Influence of inflow discharge and bed erodibility on outburst flood of landslide dam

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Journal of Mountain Science 2019年第4期16卷 778-792页

作者： ZHOU Ming-jun ZHOU Gordon G.d. CUI Kahlil Fredrick E. SONG dong-ri LU Xue-qiang Key Laboratory of Mountain Hazards and Earth Surface Process/Institute of Mountain Hazards and Environment Chinese Academy of Sciences University of Chinese Academy of Sciences

Accurate prediction of the hydrographs of outburst floods induced by landslide dam overtopping failure is necessary for hazard prevention and mitigation. In this study, flume model tests on the breaching of landslide dams were conducted. Unconsolidated soil materials with wide grain size distributions were used to construct the dam. The effects of different upstream inflow discharges and downstream bed soil erosion on the outburst peak discharge were investigated. Experimental results reveal that the whole hydrodynamic process of landslide dam breaching can be divided into three stages as defined by clear inflection points and peak discharges. The larger the inflow discharge, the shorter the time it takes to reach the peak discharge, and the larger the outburst flood peak discharge. The scale of the outburst floods was found to be amplified by the presence of an erodible bed located downstream of the landslide dam. This amplification decreases with the increase of upstream inflow. In addition, the results show that the existence of an erodible bed increases the density of the outburst flow, increasing its probability of transforming from a sediment flow to a debris flow.

关键词： Landslide dam Inflow discharge Erodible bed Outburst flood

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The effect of environmental contaminants on testicular function

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Asian Journal of Andrology 2011年第4期13卷 585-591页

作者： Premendu Prakash Mathur Shereen Cynthia d＇Cruz department of Biochemistry and Molecular Biology School of Life Sciences Pondicherry University Pondicherry 605 014 India

Male reproductive health has deteriorated considerably in the last few decades. Nutritional, socioeconomic, lifestyle and environmental factors （among others） have been attributed to compromising male reproductive health. In recent years, a large volume of evidence has accumulated that suggests that the trend of decreasing male fertility （in terms of sperm count, quality and other changes in male reproductive health） might be due to exposure to environmental toxicants. These environmental contaminants can mimic natural oestrogens and target testicular spermatogenesis, steroidogenesis, and the function of both Sertoli and Leydig cells. Most environmental toxicants have been shown to induce reactive oxygen species, thereby causing a state of oxidative stress in various compartments of the testes. However, the molecular mechanism（s） of action of the environmental toxicants on the testis have yet to be elucidated. This review discusses the effects of some of the more commonly used environmental contaminants on testicular function through the induction of oxidative stress and apoptosis.

关键词： apoptosis environmental contaminants male reproduction oxidative stress reactive oxygen species testis spermatogenesis

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Influence of surface roughness on the color of dental-resin composites

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Journal of Zhejiang University-Science B(Biomedicine & Biotechnology) 2011年第7期12卷 552-562页

作者： Razvan GHINEA Laura UGARTE-ALVAN Ana YEBRA Oscar E.PECHO Rade d.PARAVINA Maria del Mar PEREZ department of Optics Faculty of ScienceUniversity of Granada department of Stomatology Faculty of OdontologyUniversity of Granada Houston Center for Biomaterials and Biomimetics & department of Restorative dentistry and Biomaterials University of Texas Dental Branch at Houston

This study deals with the influence of surface roughness on the color of resin *** resin composites (microfilled,hybrid,and microhybrid) were each polished with 500-grit,1 200-grit,2 000-grit,and 4 000-grit SiC *** roughness parameter (Ra) was measured using a Plμ confocal microscope,and field-emission scanning electron microscope (Fe-SEM) images were used to investigate filler *** was measured using a spectroradiometer and a d65 standard illuminant (geometry diffuse/0° specular component excluded (SCE) mode).Surface roughness decreased with grit number and was not influenced by filler size or size distribution.A significant influence of Ra on lightness (L*) was *** increased with decreases in roughness,except for specimens that underwent polishing procedure 4 (PP4;500-grit,1 200-grit,2 000-grit,and 4 000-grit SiC papers consecutively).Generally,it was found that surface roughness influenced the color of resin *** composites that underwent PP1 (500-grit SiC paper) exhibited significant differences in chroma (C*),hue (h°),and lightness (L*) compared to composites that underwent PP3 (500-grit,1 200-grit,and 2 000-grit SiC papers consecutively) and *** difference (E*) between the polishing procedures was within acceptability thresholds in dentistry.

关键词： Color measurement dental resin composites Roughness

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Medical diagnosis Using Machine Learning:A Statistical Review

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Computers, Materials & Continua 2021年第4期67卷 107-125页

作者： Kaustubh Arun Bhavsar Jimmy Singla Yasser d.Al-Otaibi Oh-Young Song Yousaf Bin Zikria Ali Kashif Bashir Lovely Professional University Jalandhar144411India department of Information Systems Faculty of Computing and Information Technology in RabighKing Abdulaziz UniversityJeddah21589Saudi Arabia Software department Sejong UniversitySeoul05006Korea department of Information and Communication Engineering Yeungnam UniversityGyeongsan38541Korea department of Computing and Mathematics Manchester Metropolitan UniversityManchesterM156BHUK

decision making in case of medical diagnosis is a complicated process.A large number of overlapping structures and cases,and distractions,tiredness,and limitations with the human visual system can lead to inappropriate *** learning(ML)methods have been employed to assist clinicians in overcoming these limitations and in making informed and correct decisions in disease *** academic papers involving the use of machine learning for disease diagnosis have been increasingly getting ***,to determine the use of ML to improve the diagnosis in varied medical disciplines,a systematic review is conducted in this *** carry out the review,six different databases are *** and exclusion criteria are employed to limit the ***,the eligible articles are classied depending on publication year,authors,type of articles,research objective,inputs and outputs,problem and research gaps,and ndings and *** the selected articles are analyzed to show the impact of ML methods in improving the disease *** ndings of this study show the most used ML methods and the most common diseases that are focused on by *** also shows the increase in use of machine learning for disease diagnosis over the *** results will help in focusing on those areas which are neglected and also to determine various ways in which ML methods could be employed to achieve desirable results.

关键词： decision making disease diagnosis machine learning medical disciplines

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