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Tailoring precipitation/properties and related mechanisms for a high-strength aluminum alloy plate via low-temperature retrogression and re-aging processes

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Journal of Materials Science & Technology 2022年第25期120卷 15-35页

作者： l.g.hou H.Yu Y.W.Wang l.You Z.B.He C.M.Wu D.g.Eskin l.Katgerman l.Z.Zhuang J.S.Zhang State Key laboratory for Advanced Metals&Materials University of Science&Technology BeijingBeijing 100083China BCAST Brunel University LondonKingston LaneUxbidge Middlesex UB83PHUnited Kingdom Institute of mineral resources Chinese Academy of Geological SciencesBeijing 100037China Nanjing Advanced Transportation Equipment New Technology Research Institute Nanjing 211800China Tomsk State University Tomsk634050Russian Federation Katgerman Aluminium Technology van Beuningenlaan 102334CC LeidenNetherlands Department of Materials Science and Engineering Delft University of TechnologyMekelweg 22628CD Delftthe Netherlands

The retrogression and re-aging(RRA)processes,aimed mainly at tailoring intergranular precipitates,could significantly improve the corrosion resistance(i.e.,stress corrosion cracking resistance)without considerably decreasing the strength,which signifies that an efficient control of the size,distribution and evolution of intergranular and intragranular precipitates becomes critical for the integrated properties of the(mid-)thick high-strength Al alloy *** to RRA process with retrogression at200℃ (T77),this study investigated the impact of a modified RRA process(MT77)with lower retrogression temperatures(155-175℃ )and first-stage under-aging on the properties of a high-strength AA7050 Al alloy,in combination with detailed precipitate *** study showed that the strength/microhardness of the RRA-treated alloys decreased with raising retrogression temperature and/or prolonging retrogression time,along with the increased electrical *** rapid responsiveness of microstructure/property typical of retrogression at 200℃ was obviously postponed or decreased by using MT77 process with longer retrogression time that was more suitable for treating the(mid-)thick *** the other hand,higher retrogression temperature facilitated more intragranularηprecipitates,coarse intergranular precipitates and wide precipitate free zones,which prominently increased the electrical conductivity alongside a considerable strength loss as compared to the MT77-treated *** the preferred MT77 process,the high strength approaching T6 level as well as good corrosion resistance was ***,though a relatively homogeneous through-thickness strength was obtained,some small discrepancies of properties between the central and surface areas of an 86-mm thick 7050 Al alloy plate were observed,possibly related to the quenching *** precipitate evolution and mechanistic connection to the properties were discussed and reviewed for high-strengt

关键词： Aluminum alloy Heat treatment Precipitation Strength grain boundary

Viscosity and structure relationship with equimolar substitution of CaO with MgO in the CaO–MgO–Al_(2)O_(3)–SiO_(2)slag melts

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International Journal of Minerals,Metallurgy and Materials 2025年第1期32卷 70-79页

作者： Yong hou Shuo Zhang Jie Dang Jia guo Hanghang Zhou Xuewei lü College of Materials Science and Engineering Chongqing UniversityChongqing 400044China Chongqing Key laboratory of Vanadium-Titanium Metallurgy and New Materials Chongqing UniversityChongqing 400044China

Currently,the Al_(2)O_(3)content in the high-alumina slag systems within blast furnaces is generally limited to 16wt%–18.5wt%,making it challenging to overcome this *** most studies that concentrated on managing the MgO/Al_(2)O_(3)ratio or basicity,this paper explored the effect of equimolar substitution of MgO for CaO on the viscosity and structure of a high-alumina CaO-MgO-Al_(2)O_(3)-SiO_(2)slag system,providing theoretical guidance and data to facilitate the application of high-alumina *** results revealed that the viscosity first decreased and then increased with higher MgO substitution,reaching a minimum at 15mol%MgO *** transform infrared spectroscopy(FTIR)results found that the depths of the troughs representing[SiO_(4)]tetrahedra,[AlO_(4)]tetrahedra,and Si-O-Al bending became progressively deeper with increased MgO *** of the Raman spectra showed that the average number of bridging oxygens per Si atom and the X_(Q^(3))/X_(Q^(2))(X_(Q^(i))is the molar fraction of Q^(i) unit,and i is the number of bridging oxygens in a[SiO_(4)]tetrahedral unit)ratio increased from 2.30 and 1.02 to 2.52 and 2.14,respectively,indicating a progressive polymerization of the silicate structure.X-ray photoelectron spectroscopy(XPS)results highlighted that non-bridging oxygen content decreased from 77.97mol% to 63.41mol% with increasing MgO concentration,whereas bridging oxygen and free oxygen contents *** analysis demonstrated a gradual increase in the polymerization degree of the tetrahedral structure with the increase in MgO ***,bond strength is another important factor affecting the slag *** occurrence of a viscosity minimum can be attributed to the complex evolution of bond strengths of non-bridging oxygens generated during depolymerization of the[SiO_(4)]and[AlO_(4)]tetrahedral structures by CaO and MgO.

关键词： aluminosilicate viscosity structure spectroscopy

Non-coding RNAs in hepatitis C-induced hepatocellular carcinoma:Dysregulation and implications for early detection,diagnosis and therapy

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World Journal of gastroenterology 2013年第44期19卷 7836-7845页

作者： Weihong hou Herbert l Bonkovsky the liver Digestive and Metabolic Disorders Laboratory and the Liver-Biliary-Pancreatic Center Cannon Research Center Carolinas Medical CenterCharlotte NC 28203 United States

Hepatitis C virus(HCV)infection is one of main causes of hepatocellular carcinoma(HCC)and the prevalence of HCV-associated HCC is on the rise *** is particularly important and helpful to identify potential markers for screening and early diagnosis of HCC among high-risk individuals with chronic hepatitis C,and to identify target molecules for the prevention and treatment of *** noncoding RNAs,mainly microRNAs(miRNAs),and long non-coding RNAs(lncRNAs)with size greater than 200nucleotides,are likely to play important roles in a variety of biological processes,including development and progression of *** the most part their underlying mechanisms of action remain largely *** recent years,with the advance of high-resolution of microarray and application of next generation sequencing techniques,a significant number of non-coding RNAs(ncRNAs)associated with HCC,particularly caused by HCV infection,have been found to be differentially expressed and to be involved in pathogenesis of HCVassociated *** this review,we focus on recent studies of ncRNAs,especially miRNAs and lncRNAs related to HCV-induced *** summarize those ncRNAs aberrantly expressed in HCV-associated HCC and highlight the potential uses of ncRNAs in early detection,diagnosis and therapy of HCV-associated *** also discuss the limitations of recent studies,and suggest future directions for research in the ***,lncRNAs and their target genes may represent new candidate molecules for the prevention,diagnosis and treatment of HCC in patients with HCV *** of the potential uses of miRNAs and lncRNAs as diagnostic tools or therapies are still in their infancy.

关键词： MicroRNA long non-coding RNAs Non-coding RNAs Hepatitis C virus Hepatocellular carcinoma

Neutral responses of plant community Ca concentration to nitrogen enrichment in a semiarid grassland

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Journal of Plant Ecology 2022年第2期15卷 286-293页

作者： Shuang-li hou Xiao-Tao lü Jun-Jie Yang Erguna Forest-Steppe Ecotone Research Station CAS Key Laboratory of Forest Ecology and ManagementInstitute of Applied EcologyChinese Academy of SciencesShenyang 110016China State Key laboratory of Vegetation and Environmental Change Institute of BotanyChinese Academy of SciencesBeijing 100093China

Calcium(Ca)is an essential nutrient for plant growth and Ca concentrations in forage have important implications for ruminant diet and *** remains an open question whether forage Ca concentration would be decreased by increasing nitrogen(N)*** manipulated the increasing rates of N addition(2008–2015)in a semiarid grassland,northern *** Ca concentrations for all species were examined in each plot under N *** Ca concentrations at functional group and community levels were calculated based on the concentration of each species presented and their relative biomass in each *** found that community-level Ca concentration remained stable across a gradient of wide-ranged N addition rates,although Ca concentration at both species and functional group levels showed negative responses to N *** that forbs had higher Ca concentration than grasses,the increasing relative biomass of forbs canceled out the negative responses of species-level and functional group-level Ca *** results further showed that community Ca pool showed a positive but saturating response to N addition,with a threshold at the rate of 10 g N m^(−2)yr^(−1).Our findings highlight the role of changes in plant relative biomass in controlling the responses of forage Ca concentration and stock to N enrichment.

关键词： calcium stock community composition ecological processes global changes nitrogen deposition temperate steppe

Hydrological Variations and the Ancient Silk Road in the Northern Tarim Basin between Han and Sui Dynasties

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Acta geologica Sinica(English Edition) 2020年第3期94卷 646-657页

作者： lü Fenglin ZHANg Hua hou Juzhi CAO Xianyong lIU Chenglin Institute of Mineral Resources Chinese Academy of Geological SciencesBeijing 100037China Key laboratory of Alpine Ecology Institute of Tibetan Plateau ResearchChinese Academy of SciencesBeijing 100101China CAS Center for Excellence in Tibetan Plateau Earth Sciences Chinese Academy of SciencesBeijing 100101China

The fluctuation pattern of China’s civilization can be ascribed to climate change and historical geopolitical variations. The ancient Silk Road served as the most prosperous route connecting East Asia and Europe during Han Dynasty(206 BC–220 AD) and Sui-Tang Dynasties(581–907 AD), but was deserted in Wei, Jin, Northern and Southern dynasties(220–580 AD), of which the Tarim Basin was a key area. However, our understanding about the decline of the route during this period remains limited. Here, we present an ~7-year resolution record based on optically stimulated luminescence(OSl) age-depth model(ca. 120 BC–750 AD) from luntai(lT) profile, about 5 km from the modern Tarim River, which fed the ancient oases, to assess the potential causes on the documented decline of the ancient Silk Road between late Han and Sui dynasties. In this study, five episodes of hydrological change were identified by combining grain size, magnetic susceptibility, geochemistry and TOC/TN contents. Our reconstruction reveals that cold and wet climate dominated at 120 BC–50 AD and 550–750 AD, respectively, indicated by strong hydrodynamic conditions. Relatively warm and humid climate occurred at 120–550 AD, between Eastern Han and Sui-Tang dynasties, indicating a better and more suitable local environment. A comparison between the studied region and other areas of China demonstrates that the paleoclimatic variations in eastern and western China exhibit rough discrepancies, and the hydrological conditions in arid region is inconsistent with the decline of ancient Silk Road in the northern Tarim Basin. We suggest that political and societal factors are the key issues that caused the interruption of Silk Road during Wei, Jin, Northern and Southern dynasties, such as the co-occurrence of societal crises, turmoil and division in eastern China, rather than the deteriorating climatic condition in the northern Tarim basin.

关键词： hydrological changes paleochannel paleoclimate climate change Silk Road

Nitrogen addition reduced carbon mineralization of aggregates in forest soils but enhanced in paddy soils in South China

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Ecological Processes 2021年第1期10卷 597-607页

作者： Ruirui Cao longchi Chen Xincun hou Xiaotao lü Haimei li College of landscape Architecture and Forestry Qingdao Agricultural UniversityQingdao 266109China. Huitong Experimental Station of Forest Ecology CAS Key Laboratory of Forest Ecology and ManagementInstitute of Applied EcologyChinese Academy of SciencesShenyang 110016China. Hunan Key laboratory for Structure and Ecosystem Service of Subtropical Forest Huitong National Research Station of Forest EcosystemHuitong 418307China. Research and Development Center for grasses and Environment Beijing Academy of Agriculture and Forestry SciencesBeijing 100097China.

Background:Despite the crucial role of nitrogen(N)availability in carbon(C)cycling in terrestrial ecosystems,soil organic C(SOC)mineralization in different sizes of soil aggregates under various land use types and their responses to N addition is not well *** investigate the responses of soil C mineralization in different sized aggregates and land use types to N addition,an incubation experiment was conducted with three aggregate-size classes(2000,250,and 53μm)and two land use types(a Chinese fir plantation and a paddy land).Results:Cumulative C mineralization of theghest and that of microaggregates was the lowest in both forest and paddy soils,indicating that soil aggregates enhanced soil C stability and reduced the loss of soil *** C mineralization in all sizes of aggregates treated with N addition decreased in forest soils,but that in microaggregates and thels treated with 100μgNg−***,the effect sizes of N addition on C mineralization of forest soils were below zero,but those of paddy soils were above *** data indicated that N addition decreased SOC mineralization of forest soils but increased that of paddy ***:Soil aggregates play an important role in soil C sequestration,and decrease soil C loss through the increase of soil C stability,regardless of land use types.N addition has different effects on soil C mineralization in different land use *** results highlight the importance of soil aggregates and land use types in the effects of N deposition on the global terrestrial ecosystem C cycle.

关键词： Ultisol land use type Microaggregates Soil organic carbon

A Duplex grain Structure of Dense(K,Na)NbO_(3) Ceramics Constructed by Using Microcrystalline as Seed

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Journal of Wuhan University of Technology(Materials Science) 2022年第3期37卷 385-392页

作者： lIU liangliang JIANg Xinyu lü Rui gUO Zhuangzhuang hou Zhaoping College of Materials Science and Engineering Taiyuan University of TechnologyTaiyuan 030024China

A new raw material was developed for the preparation of dense(K,Na)NbO_(3)(KNN)*** the absence of dopants,two kinds of KNN powder,calcined and microcrystalline powder,were used as matrix and seed to construct a duplex grain *** former was synthesized by the traditional solid phase reaction method and the latter by molten salt *** effects of microcrystalline powder content on sintering behavior,microstructure and electric properties were *** was found that appropriate microcrystalline powder content(x=0.4)promoted the grain growth and the gas diffusion,which resulted in a denser duplex grain structure and obtained a wide sintering temperature *** work gives a basic raw material system for the development of high performance KNN *** addition,it also provides a new way to prepare dense ceramics by the design of a duplex structure.

关键词： niobate piezoelectric ceramics microstructure microcrystalline

STRESS ANAlYSIS OF THE APERTURE IN COMPOUND PIPElINE BY FEM

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Acta Metallurgica Sinica(English letters) 2007年第5期20卷 385-390页

作者： J.g. Yang H.Y. Fang C.l. Fan Z. luo X.Z. hou State Key laboratory of Advanced Welding Production Technology Harbin Institute of Technology Harbin 150001 China School of Material Science and Engineering Tianjin University Tianjin 300072 China Daqing Oil-ghem-Wdding Institute Daqing 163712 China

There is a cyclical aperture at a certain part of the fiberglass reinforced plastic compound pipeline with a stainless steel pipe as a liner, which becomes the weakness of the conduit. The field of stress and strain of the aperture was investigated using the nonliner finite element code Marc. The results of the finite element analysis showed that there were concentrations of stress and strain in the layer of stainless steel at the part of the pipeline where the aperture existed. The method to solve these problems was also discussed.

关键词： compound pipeline stress software Marc

Intelligent Visual Media Processing： When graphics Meets Vision

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Journal of Computer Science & Technology 2017年第1期32卷 110-121页

作者： Ming-Ming Cheng Qi-Bin hou Song-Hai Zhang Paul l. Rosin College of Computer Science and Control Engineering Nankai University Tianjin 300071 China TNlist Tsinghua University Beijing 100084 China School of Computer Science and Informatics Cardiff University Wales CF10 3EU U.K.

The computer graphics and computer vision communities have been working closely together in recent years and a variety of algorithms and applications have been developed to analyze and manipulate the visual media around us. There are three major driving forces behind this phenomenon： 1） the availability of big data from the Internet has created a demand for dealing with the ever-increasing, vast amount of resources; 2） powerful processing tools, such as deep neural networks, provide effective ways for learning how to deal with heterogeneous visual data; 3） new data capture devices, such as the Kilxect, the bridge betweea algorithms for 2D image understanding and 3D model analysis. These driving forces have emerged only recently, and we believe that the computer graphics and computer vision communities are still in the beginning of their honeymoon phase. In this work we survey recent research on how computer vision techniques benefit computer graphics techniques and vice versa, and cover research on analysis, manipulation, synthesis, and interaction. We also discuss existing problems and suggest possible further research directions.

关键词： computer graphics computer vision survey scene understanding image manipulation