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Risk factors for de novo hepatitis B during solid cancer treatment 被引量:1
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作者 Rie Sugimoto Masayuki Furukawa +10 位作者 Takeshi Senju Yoshihusa Aratake Yuki Tanaka Hiroki Inada Tatsuya Noguchi Lingaku Lee Masami Miki Yuji Maruyama Risa Hashimoto Terumasa Hisano Mototsugu Shimokawa 《World Journal of Clinical Cases》 SCIE 2020年第24期6264-6273,共10页
BACKGROUND Reactivation of hepatitis B virus(HBV)during anticancer treatment is a critical issue.When treating patients with solid tumors,it is unclear whether specific cancer types or treatments affect HBV reactivati... BACKGROUND Reactivation of hepatitis B virus(HBV)during anticancer treatment is a critical issue.When treating patients with solid tumors,it is unclear whether specific cancer types or treatments affect HBV reactivation in hepatitis B surface antigen(HBsAg)-negative and hepatitis B core antibody(HBcAb)-positive patients,socalled de novo hepatitis B patients.The risk of de novo hepatitis B may vary based on different background factors.AIM To determine the frequency and risk factors for de novo hepatitis B during solid tumor treatment.METHODS This retrospective cohort study comprised 1040 patients without HBsAgs and with HBcAbs and/or hepatitis B surface antibodies(HBsAbs).The patients were treated for solid cancer from 2008 to 2018 at the National Kyushu Cancer Center and underwent HBV DNA measurements.Patient characteristics and disease and treatment information were investigated.HBV DNA measurements were performed using TaqMan polymerase chain reaction(PCR).To identify the risk factors associated with HBV DNA expression,the age,sex,original disease,pathology,treatment method,presence or absence of hepatitis C virus(HCV),and HBsAb and/or HBcAb titers of all subjects were investigated.In patients with HBV DNA,the time of appearance,presence of HBsAgs and HBsAbs at the time of appearance,and course of the subsequent fluctuations in virus levels were also investigated.RESULTS Among the 1040 patients,938 were HBcAb positive,and 102 were HBcAb negative and HBsAb positive.HBV DNA expression was observed before the onset of treatment in nine patients(0.9%)and after treatment in 35 patients(3.7%),all of whom were HBcAb positive.The HBV reactivation group showed significantly higher median HBcAb values[9.00(8.12-9.89)vs 7.22(7.02-7.43),P=0.0001]and significantly lower HBsAb values(14 vs 46,P=0.0342)than the group without reactivation.Notably,the reactivated group showed a significantly higher proportion of cancers in organs related to digestion and absorption(79.0%vs 58.7%,P=0.0051).A high HBcAb titer and cancers in organs involved in digestion and absorption were identified as independent factors for HBV reactivation(multivariate analysis,P=0.0002 and P=0.0095).The group without HBsAbs tended to have a shorter time to reactivation(day 43 vs day 193),and the frequency of reactivation within 6 mo was significantly higher in this group(P=0.0459)than in the other group.CONCLUSION A high HBcAb titer and cancers in organs involved in digestion and absorption are independent factors that contribute to HBV reactivation during solid tumor treatment. 展开更多
关键词 Hepatitis B REACTIVATION solid cancer treatment Digestion and absorption organ Hepatitis B surface antibody Hepatitis B core antibody titer
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Effect of Semi-Solid Isothermal Heat Treatment on Microstructure of ZL104 Aluminum Alloy 被引量:2
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作者 Yang Mingbo Shen Jia 《稀有金属材料与工程》 SCIE EI CAS CSCD 北大核心 2009年第A03期95-99,共5页
The feasibility of fabricating ZL104 aluminum alloy with non-dendritic microstructure by semi-solid isothermal heat treatment process and the effects of holding temperature and time on the semi-solid isothermal heat-t... The feasibility of fabricating ZL104 aluminum alloy with non-dendritic microstructure by semi-solid isothermal heat treatment process and the effects of holding temperature and time on the semi-solid isothermal heat-treated microstructure of the alloy, are investigated. The research results indicate that it is possible to produce ZL104 alloy with non-dendritic microstructure by a suitable semi-solid isothermal heat treatment. After treated at 580 ℃ for 120 min, the ZL104 alloy can obtain a non-dendritic microstructure with an 49% liquid content and an average size range of 115 μm of the unmelted primary solid particles. In addition, an increase in the holding time from 30 to 120 min for a given holding temperature of 580 ℃ or in the holding temperature from 570 to 580 ℃ for a given holding time of 120 min causes the average size and globular tendency of unmelted primary solid particles in the semi-solid ZL104 alloy to decrease and become more obvious, respectively. 展开更多
关键词 铝合金 热处理过程 微观结构 物理性能
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Diagnosis and treatment of solid-pseudopapillary tumor of the pancreas 被引量:18
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作者 Hao Zhang, Ting-Bo Liang, Wei-Lin Wang, Yan Shen, Guo-Ping Ren and Shu-Sen Zheng Department of Hepatobiliary Surgery , and Department of Pathology, First Affiliated Hospital, Zhejiang University School of Medicine, Hangzhou 310003, China 《Hepatobiliary & Pancreatic Diseases International》 SCIE CAS 2006年第3期454-458,共5页
BACKGROUND: Solid-pseudopapillary tumor (SPT) of the pancreas is a rare exocrine pancreatic tumor. Despite the increasing recognition of the tumor in recent years, its pathogenesis and apparent therapeutic algorithm r... BACKGROUND: Solid-pseudopapillary tumor (SPT) of the pancreas is a rare exocrine pancreatic tumor. Despite the increasing recognition of the tumor in recent years, its pathogenesis and apparent therapeutic algorithm remain unclear. This study was designed to define the clinical, imaging, and pathologic features and to improve the diagnosis and treatment of this rare disease. METHOD: The clinical, imaging, and pathologic findings of 9 SPT patients managed in our hospital between 2001 and 2005 were retrospectively analyzed, and related literatures were reviewed. RESULTS: In the 9 patients aged from 14 to 68 years, 8 were female and 1 male. The mean age of these patients at diagnosis was 30 years. Initially, 8 patients complained of vague abdominal pain and one patient had pancreatic mass detected incidentally by abdominal CT. The levels of blood and urine amylase and tumor markers were all within the normal range. B-US, CT and MRI demonstrated that tumors were well encapsulated and contained some degree of internal hemorrhage or cystic degeneration. The mean transverse diameter of these tumors was 5.4 cm (range, 2-10.5 cm). The tumors were located at the head (2 patients), body (2), body and tail junction (4), and tail (1) of the pancreas. Surgical procedures included pancreaticoduodenectomy, distal pancreatectomy, distal pancreatectomy with splenectomy, and enucleation. Histological examination showed solidified cystic areas and papillary protrusions. Two malignant tumors demonstrated retroperitoneal metastases and vascular invasion. Follow-up for 2.5 years on average showed that one patient died of tumor recurrence at 10 months and the rest were alive. CONCLUSIONS: SPT exhibits unique clinical and pathologic features and is readily diagnosed by its characteristic imaging and histological appearance. Surgical resection of the primary tumor and metastases is the treatment of choice. 展开更多
关键词 solid-pseudopapillary tumor PANCREAS DIAGNOSIS treatment
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Microstructure evolution of semi-solid Mg-14Al-0.5Mn alloys during isothermal heat treatment 被引量:4
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作者 张亮 曹占义 刘勇兵 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2010年第7期1244-1248,共5页
A new Mg-14Al-0.5Mn alloy that exhibits a wide solidification range and sufficient fluidity for semi-solid forming was designed.And the microstructure evolution of semi-solid Mg-14Al-0.5Mn alloy during isothermal heat... A new Mg-14Al-0.5Mn alloy that exhibits a wide solidification range and sufficient fluidity for semi-solid forming was designed.And the microstructure evolution of semi-solid Mg-14Al-0.5Mn alloy during isothermal heat treatment was investigated. The mechanism of the microstructure evolution and the processing conditions for isothermal heat treatment were also discussed.The results show that the microstructures of cast alloys consist ofα-Mg,β-Mg17Al12 and a small amount of Al-Mn compounds.After holding at 520℃ for 3 min,the phases ofβ-Mg17Al12 and eutectic mixtures in the Mg-14Al-0.5Mn alloy melt and the microstructures ofα-Mg change from developed dendrites to irregular solid particles.With increasing the isothermal time,the amount of liquid increases,and the solid particles grow large and become spherical.When the holding time lasts for 20 min or even longer,the solid and liquid phases achieve a state of dynamic equilibrium. 展开更多
关键词 半固态成型 铸造合金 组织演变 等温处理 热处理过程 微观结构 固体颗粒
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Effect of isothermal heat treatment on semi-solid microstructure of AZ91D magnesium alloy containing rare earth Gd 被引量:10
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作者 Yong Hu Li Rao Xu-wu Ni 《China Foundry》 SCIE CAS 2015年第1期20-25,共6页
The AZ91 D magnesium alloy containing rare earth Gd was prepared in this study, and the effect of semi-solid isothermal heat treatment on the microstructure of the alloy was investigated to obtain an optimum semi-soli... The AZ91 D magnesium alloy containing rare earth Gd was prepared in this study, and the effect of semi-solid isothermal heat treatment on the microstructure of the alloy was investigated to obtain an optimum semi-solid structure. Results show that Gd can refine the microstructure of AZ91 D magnesium alloy, and the optimum semi-solid AZ91 D microstructure can be achieved by adding 1.5wt.% Gd. After treated at 585 °C for 30 min, the well distributed rose-shaped and near-spherical semi-solid microstructures of AZ91D+1.5wt.%Gd alloy can be obtained. The liquid phase of the semi-solid alloy consists of three components, namely, the molten pool, the "entrapped liquid" pool and the liner liquid film which separates two neighbor particles. The solid phase is composed of two phases, the primary α-Mg particles and the α-Mg phase formed in the second stage of solidification. With the increase of holding time, melting which causes the decrease of the primary α-Mg particle size is the dominant mechanism in the initial stage while coalescence and Ostwald ripening tend to be the principles later. 展开更多
关键词 isothermal heat treatment semi-solid processing AZ91D GADOLINIUM
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Microstructural evolution of equal channel angular pressed AZ91D magnesium alloy during semi-solid isothermal heat treatment 被引量:2
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作者 Chen Tijun Lu Guoxiang Hao Yuan 《China Foundry》 SCIE CAS 2008年第4期234-239,共6页
The microstructural evolution of AZ91D magnesium alloy processed by equal channel angular pressing during isothermal heat treatment at 570℃was investigated.The results indicated that the equal channel angular pressin... The microstructural evolution of AZ91D magnesium alloy processed by equal channel angular pressing during isothermal heat treatment at 570℃was investigated.The results indicated that the equal channel angular pressing followed by semi-solid isothermal heat treatment was an effective method to prepare semi-solid nondendritic slurry of AZ91D magnesium alloy.During this process,its microstructure change underwent four stages,the initial coarsening stage,the structure separation stage,the spheroidization stage and the final coarsening stage.The microstructural spheroidization effect was the best after being heated for 15 min for the alloy pressed for four passes,and the grain size was the smallest.With the further increase of heating time,the grain size and shape factor increased.When the heating time was kept constant,the grain size and shape factor decreased with the increase of pressing passes. 展开更多
关键词 镁合金 建筑材料 金属材料 凝固
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Effects of high-pressure heat treatment on the solid-state phase transformation and microstructures of Cu_(61.13)Zn_(33.94)Al_(4.93) alloys 被引量:7
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作者 王海燕 刘建华 +1 位作者 彭桂荣 王文魁 《Chinese Physics B》 SCIE EI CAS CSCD 2010年第9期469-474,共6页
The phase transformation activation energy of the Cu61.13Zn33.94A14.93 alloys, which were treated at 4 GPa and 700 ℃ for 15 minutes, was calculated by means of differential scanning calorimetry curves obtained at var... The phase transformation activation energy of the Cu61.13Zn33.94A14.93 alloys, which were treated at 4 GPa and 700 ℃ for 15 minutes, was calculated by means of differential scanning calorimetry curves obtained at various heating and cooling rates. Then, the effects of high-pressure heat treatments on the solid-state phase transformation and the microstructures of Cu61.13Zn33.94A14.93 alloys were investigated. The results show that high-pressure heat treatments can refine the grains and can change the preferred orientation from (111) to (200) of α phase. Compared with the as-cast alloy, the sample with high-pressure heat treatment has finer grains, lower β'→β and/β→β' transformation temperature and activation energy. Furthermore, we found that high cooling rate favours the formation of fine needle-like α phase in the range of 5-20℃/min. 展开更多
关键词 Cu61.13Zn33.94A14.93 alloy high-pressure heat treatment solid-state phase transformation MICROSTRUCTURES
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Effect of holding time on microstructure of Mg-9Al-1Si alloy during semisolid isothermal heat treatment 被引量:1
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作者 马国睿 李新林 李庆芬 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2010年第B07期430-434,共5页
The effects of isothermal holding time on the semisolid microstructure of Mg-9Al-1Si(mass fraction,%)alloy were investigated.The research results indicate that the Mg-9Al-1Si alloy with non-dendritic microstructure ca... The effects of isothermal holding time on the semisolid microstructure of Mg-9Al-1Si(mass fraction,%)alloy were investigated.The research results indicate that the Mg-9Al-1Si alloy with non-dendritic microstructure can be produced by the semi-solid isothermal heat treatment.With holding time varying from 5 to 30 min,the volume fraction of liquid is gradually enlarged from 29.3%to 38.6%,the morphology ofα-Mg grains changes from initial dendritic shape to spherical types and their average sizes increases from 41.1 to 56.1μm.In addition,during the isothermal heat treatment,the eutectic Mg2Si phase changes from the initial Chinese script shape to granule and/or polygon shape in Mg-9Al-1Si alloy.The modification of Mg2Si phase is possibly attributed to a shift of the eutectic composition of the liquid in semi-solid slurries,towards lower silicon contents with increasing Al content due to a redistribution of Al during isothermal heat treatment. 展开更多
关键词 半固态浆料 等温处理 热处理过程 保温时间 合金 非枝晶组织 MG2SI 形状变化
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Influence of semi-solid isothermal treatment on eutectic carbide in Cr12MoV steel 被引量:1
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作者 Li Qingchun Yang Bo +2 位作者 Li Chong Wang Chao Chang Guowei 《China Foundry》 SCIE CAS 2014年第6期498-502,共5页
In-situ observation of eutectic solidification of Cr12MoV steel was conducted using high temperature confocal laser-scanning microscopy. The semi-solid isothermal treatment temperature of the steel was determined by t... In-situ observation of eutectic solidification of Cr12MoV steel was conducted using high temperature confocal laser-scanning microscopy. The semi-solid isothermal treatment temperature of the steel was determined by thermodynamic calculation using Thermo-cal software. At the same time, the infl uences of isothermal treatment temperature and time on eutectic carbides in the steel were also studied. The results show that when the liquid metal cools at the rate of 47 °C·min-1, the eutectic reaction occurs rapidly at 1,214.7 °C in one second with the reticular liquid around austenite dendrites, transforming into a network of eutectic structure. After being held at 1,300 °C for 30 min, the carbide network is broken due to the impingement of refi ned primary austenite dendrites and secondary dendrites arms, and the thickness of eutectic structure is reduced. 展开更多
关键词 semi-solid state isothermal treatment eutectic carbide
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Microstructural evolution of Mg9AlZnY alloy with vibration in lost foam casting during semi-solid isothermal heat treatment 被引量:4
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作者 赵忠 樊自田 +1 位作者 蒋文明 董选普 《中国有色金属学会会刊:英文版》 CSCD 2010年第S3期768-773,共6页
The nearly equiaxed grains of Mg9AlZnY alloy were obtained by vibrating solidification in lost foam casting(LFC) and the microstructure of Mg9AlZnY alloy was analyzed.On this basis,the morphology and size of α-Mg gra... The nearly equiaxed grains of Mg9AlZnY alloy were obtained by vibrating solidification in lost foam casting(LFC) and the microstructure of Mg9AlZnY alloy was analyzed.On this basis,the morphology and size of α-Mg grains fabricated by semi-solid isothermal heat treatment(SSIT) at 530 ℃ and 570 ℃ holding different time were studied.The results show that the main constituent phases of Mg9AlZnY alloy are α-Mg,β-Mg17Al12 and Al2Y,and the Y can greatly refine α-Mg grains.The distribution of α-Mg grains equivalent diameters between 20 and 100 μm is up to 87%,and the average roundness of α-Mg grains reaches 1.37 in the specimen obtained at 570 ℃ and holding time 60 min.According to the analysis of solidification kinetics and thermodynamic,binary eutectic with low melting point melts firstly on SSIT process.As the liquid fraction increases with the solute diffusibility,both of the shape and size of α-Mg grains change ceaselessly.When the liquid fraction reaches equilibrium,the α-Mg grains are gradually spheroidized under the interfacial tension,and then the α-Mg grains begin to combine and grow.Evolution of α-Mg dendritic grains on SSIT process is obviously different from that of equiaxed grains. 展开更多
关键词 LOST foam casting(LFC) SEMI-solid ISOTHERMAL heat treatment(SSIT) MICROSTRUCTURAL evolution magnesium ALLOY
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Effects of Sm addition on microstructural evolution of Mg-6Zn-0.4Zr alloy during semi-solid isothermal heat treatment 被引量:6
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作者 Yu Zhang Xiao-feng Huang +2 位作者 Ying Ma Ti-jun Chen Yuan Hao 《China Foundry》 SCIE 2017年第2期85-92,共8页
The application of segmental semi-solid thixoforming of magnesium alloys is confined due to the dimensional distinction existing in solid particles of the alloy billet from edge to center zones. In the present study, ... The application of segmental semi-solid thixoforming of magnesium alloys is confined due to the dimensional distinction existing in solid particles of the alloy billet from edge to center zones. In the present study, the effects of Sm addition on the microstructural evolution of Mg-6Zn-0.4Zr and Mg-6Zn-4Sm-0.4Zr alloys by semi-solid isothermal heat treatment were investigated, to obtain optimum semi-solid microstructures for the subsequently thixoforming. The results indicate that the grains of the Sm-bearing alloy are evidently refined and gradually evolve from dendritic to globular and elliptic particles. In addition, the distinctly dimensional effect of the Mg-6Zn-0.4Zr alloy is eliminated with 4% Sm addition; the particle sizes in all zones from center to the edge of the billet are almost identical. With the increment of isothermal heat treatment temperature, the dendritic microstructures completely disappear, and meanwhile, the irregular and globular particles gradually form. The size, morphology and the distribution of solid particles mainly depend on the formation and permeation of the liquid phase in the process of isothermal heat treatment. As the isothermal temperature increases from 570 °C to 610 °C, the average size and shape factor of solid particles of both the alloys with and without Sm addition gradually decrease while the liquid fraction gradually increases. 展开更多
关键词 Mg-Zn-Zr 镁合金 维的效果 SM 半固体等温的热处理 非树枝状的微观结构 TG146.22 A
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Effects of trace Cr on as-cast microstructure and microstructural evolution of semi-solid isothermal heat treatment ZC61 magnesium alloy 被引量:4
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作者 Xiao-feng Huang Ya-jie Ma +2 位作者 Qiao-qiao Zhang Lang-lang Wei Jian-qiao Yang 《China Foundry》 SCIE 2019年第1期53-62,共10页
The content and kind of trace elements in magnesium alloys have important effects on their ascast and semi-solid microstructures. In this research work, effects of trace Cr on as-cast and semi-solid microstructures of... The content and kind of trace elements in magnesium alloys have important effects on their ascast and semi-solid microstructures. In this research work, effects of trace Cr on as-cast and semi-solid microstructures of ZC61 magnesium alloy were investigated by metal mold casting and semi-solid isothermal heat treatment. The results show that the addition of Cr can refine the α-Mg phase without generating a new phase, noticeably change the eutectic phase, and decrease the average size of solid particles at the same isothermal heat treatment conditions. Non-dendritic microstructures of all alloys are constituted of α_1-Mg phases, α_2-Mg phases and eutectic phases after water quenching. With isothermal temperature increased or holding time prolonged, the eutectic microstructure(α-Mg+MgZn_2+CuMgZn) at the grain boundaries in as-cast alloy is melted preferentially and then turned into semi-solid non-dendritic microstructure by processes of initial coarsening, microstructure separation, spheroidizing and final coarsening. Especially when the ZC61-0.1 Cr alloy was treated at 585 ℃ for 30 min, the ideal non-dendritic microstructure can be obtained, and the corresponding solid particle size and shape factor were 37.5 μm and 1.33, respectively. The coarsening process of solid α-Mg phase at higher temperature or longer time, which is affected by both combining growth and Ostwald ripening mechanism, is refrained when Cr is added to the ZC61 alloy. 展开更多
关键词 ZC61 magnesium alloy CR content SEMI-solid isothermal heat treatment NON-DENDRITIC microstructure MICROSTRUCTURAL evolution
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Effect of Intermediate Heat Treatment Temperature on Microstructure and Notch Sensitivity of Laser Solid Formed Inconel 718 Superalloy 被引量:4
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作者 刘奋成 黄卫东 《Journal of Wuhan University of Technology(Materials Science)》 SCIE EI CAS 2011年第5期908-913,共6页
Inconel 718 superalloys deposited by laser solid forming (LSF) were heat treated with solution treatment,intermediate heat treatment (IHT) and two-stage aging treatment in sequence (SITA heat treatment).The effe... Inconel 718 superalloys deposited by laser solid forming (LSF) were heat treated with solution treatment,intermediate heat treatment (IHT) and two-stage aging treatment in sequence (SITA heat treatment).The effect of IHT temperature on microstructure,tensile property and notch sensitivity of LSFed Inconel 718 superalloy at 500 ℃ were investigated.As-deposited columnar grains have transformed to equiaxed grains and the grains were refined due to the recrystallization during the SITA heat treatment.It is found that the size and amount of δ phase dispersed at grain boundaries decreased with the increasing of IHT temperature,and δ phase disappeared when the IHT temperature reached 1 020 ℃.The ultimate tensile strength (UTS) and yield strength (YS) of smooth samples increased to a maximum when the IHT temperature reached 980 ℃ and then decreased slightly to a minimum when the IHT temperature was 1 000 ℃,and followed by slight increasing again till the IHT temperature reached 1 020 ℃,resulted from the competition of precipitation strengthening effect of γ″ and γ' phase and the grain boundary weakening effect caused by the gradual disappearance of δ phase with increasing the IHT temperature.The notch sensitivity factor (qe) decreased but still greater than 1 as the IHT temperature increased,which is attributed to the decrease of the size and amount of δ precipitation. 展开更多
关键词 notch sensitivity Inconel 718 laser solid forming intermediate heat treatment SUPERALLOY
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Structural evolution of ZA27 alloy during semi-solid isothermal heat treatment 被引量:4
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作者 陈体军 马颖 +3 位作者 郝远 陆松 许广济 孙军 《中国有色金属学会会刊:英文版》 CSCD 2001年第1期98-102,共5页
The structural evolution of ZA27 alloy modified by element Zr was studied during semi solid isothermal heat treatment, and its transformation mechanism was also discussed. The results indicate that the primary α phas... The structural evolution of ZA27 alloy modified by element Zr was studied during semi solid isothermal heat treatment, and its transformation mechanism was also discussed. The results indicate that the primary α phase changes from equiaxed grains to spherical grains gradually at semi solid temperature of 460 ℃. With increasing isothermal time, the eutectic between boundaries of α phase diffuses toward α phase, and the primary equiaxed grain arms merge and boundaries tend to disappear to form near particle grains. Further, the eutectic left on α boundaries melts to make the near particle grains separate, and form spherical structure at last. [ 展开更多
关键词 ZA27 alloy SEMI-solid state ISOTHERMAL HEAT treatment STRUCTURAL evolution SPHERICAL structure
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Experimental Study on Application of A Charging Flocculation Agent for Treatment of Turbidity and Suspended Solid in Catfish Farming Water in Vinh Long Province
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作者 Phung Chi Sy 《Journal of Environmental Science and Engineering(B)》 2016年第7期348-354,共7页
关键词 悬浮固体 养殖水体 絮凝剂 实验 治疗 鲶鱼 应用 充电
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Research achievements and application in anaerobic treatment of organic solid wastes—A review
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作者 周富春 熊德国 +1 位作者 鲜学福 徐龙君 《Chinese Journal Of Geochemistry》 EI CAS 2006年第2期178-181,共4页
Anaerobic digestion is a good method, which possesses the optimal combination of volume reduction, probability of success and potential for resource and energy recovery. However, relatively little research has been do... Anaerobic digestion is a good method, which possesses the optimal combination of volume reduction, probability of success and potential for resource and energy recovery. However, relatively little research has been done on the anaerobic digestion of organic solid wastes (OSW), especially in China. However, different substrates, start-up conditions, micro-organisms, processing technologies, pre-treatment methods could influence the result of anaerobic digestion. Anaerobic treatment of municipal OSW is less than that of wastewaters because some problems and obstructions need to be solved. Meanwhile, the application of anaerobic digestion of OSW is also discussed in the present paper. 展开更多
关键词 有机固体废物 厌氧性处理 环境污染 环境处理
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Influence of Semi-Solid Isothermal Heat Treatment on Microstructure of Gray Cast Iron
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作者 Naglaa Fathy 《Journal of Minerals and Materials Characterization and Engineering》 2013年第6期326-330,共5页
Materials serve as an enabling technology contributing to solutions in problems of concern to society. In this research, the effect of semi-solid isothermal heat treatment on graphite morphologies and matrix structure... Materials serve as an enabling technology contributing to solutions in problems of concern to society. In this research, the effect of semi-solid isothermal heat treatment on graphite morphologies and matrix structure for gray cast iron were studied. Microstructure observations and measurements of flaky graphite morphology are reported as a function of isothermal heating time range of 5 to 25 minutes after isothermal heating temperature at 1163℃. The effect heating time, on the semisolid microstructures during partial re-melting was investigated. Flack graphite morphology was changed significantly by isothermal heating of gray cast iron at 1163℃ for heating time above 15 min resulting fine graphite morphology in matrix structure. Hardness increases with increasing heating time due to the amount of cementite and fine pearlite matrix for air cooled gray cast iron. The optimum heating treatment condition was achieved at the temperature of 1163℃ for the range of 15 to 20 min. 展开更多
关键词 SEMI-solid Heat treatment ISOTHERMAL GRAY CAST IRON MICROSTRUCTURE
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Abnormal mechanical property evolution induced by heat treatment for a semi-solid forming hypereutectic Al-Fe base alloy
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作者 Run-xia Li Qing Li +3 位作者 Guo-qing Ren Yan-jiao Tong Bao-yi Yu Xiao-guang Yuan 《China Foundry》 SCIE CAS 2015年第3期208-213,共6页
In the present study, Al-5.5Fe-4Cu-2Zn-0.4Mg-0.5Mn al oy samples were prepared by electromagnetic stirring and semi-solid forming processing, and then the effects of T6 and T1 heat treatments on the microstructures an... In the present study, Al-5.5Fe-4Cu-2Zn-0.4Mg-0.5Mn al oy samples were prepared by electromagnetic stirring and semi-solid forming processing, and then the effects of T6 and T1 heat treatments on the microstructures and mechanical properties of the semi-solid forming samples were investigated. The results indicate that after semi-solid forming, the mechanical properties of the sample improved significantly compared to that of the merely electromagnetically stirred sample. The grains of semi-solid forming alloy became almost fine equiaxed; big long strip-shaped Al3 Fe phases became short rod-like morphology and distributed uniformly in the matrix. However, the mechanical properties of the T6-treated semi-solid forming sample decreased significantly instead of increasing and, with solution temperature rising, the tensile strength of the al oy decreased further. The results of EDS show that after high temperature solid-solution treatment, the Cu element in the semi-solid forming alloy sample is mainly concentrated at the boundaries of the Al3 Fe phases instead of being dissolved in the matrix. At the same time, the grains of the semi-solid forming sample grew slightly after solid-solution treatment. Therefore, the growth of the grains and the accumulation of Cu element at Al3 Fe phase boundaries during solution treatment of the semi-solid forming alloy were the main reasons for the mechanical properties decreasing after T6 treatment. The mechanical properties of the alloy were improved after T1 heat treatment due to aging strengthening phase being precipitated in the matrix. 展开更多
关键词 Al-Fe base alloys semi-solid forming heat treatment MICROSTRUCTURES
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Influence of FeO and sulfur on solid state reaction between MnO-SiO_2-FeO oxides and an Fe-Mn-Si solid alloy during heat treatment at 1473 K
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作者 Cheng-song Liu Shu-feng Yang +3 位作者 Kyung-ho Kim Jing-she Li Hiroyuki Shibata Shin-ya Kitamura 《International Journal of Minerals,Metallurgy and Materials》 SCIE EI CAS CSCD 2015年第8期811-819,共9页
To clarify the influence of Fe O and sulfur on solid state reaction between an Fe-Mn-Si alloy and Mn O-Si O2-Fe O oxides under the restricted oxygen diffusion flux, two diffusion couples with different sulfur contents... To clarify the influence of Fe O and sulfur on solid state reaction between an Fe-Mn-Si alloy and Mn O-Si O2-Fe O oxides under the restricted oxygen diffusion flux, two diffusion couples with different sulfur contents in the oxides were produced and investigated after heat treatment at 1473 K. The experimental results were also compared with previous work in which the oxides contained higher Fe O. It was found that although the Fe O content in the oxides decreased from 3wt% to 1wt% which was lower than the content corresponding to the equilibrium with molten steel at 1873 K, excess oxygen still diffused from the oxides to solid steel during heat treatment at 1473 K and formed oxide particles. In addition, increasing the sulfur content in the oxides was observed to suppress the diffusion of oxygen between the alloy and the oxides. 展开更多
关键词 REFINING solid state reactions heat treatment incl
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Microstructural Evolution of Cast Hyper-Eutectic Al-18% Si Alloy during Cyclic Semi-Solid Heat Treatment
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作者 Mohamed Ramadan 《Journal of Minerals and Materials Characterization and Engineering》 2015年第5期390-398,共9页
The cyclic semi-solid heat treatment represents a promising technique for improving microstructure and mechanical properties of a wide range of metallic alloys. In the current research the influence of cyclic semi-sol... The cyclic semi-solid heat treatment represents a promising technique for improving microstructure and mechanical properties of a wide range of metallic alloys. In the current research the influence of cyclic semi-solid heat treatment on microstructure of Al-18% Si alloy containing 0.8% Fe has been studied. All specimens were heated in an electrically heated resistance furnace with heating rate of 10°C·min-1 to 585°C. For a complete one cycle heat treatment (5 min heating time), samples after 5 min holding at 585°C were cooled to a temperature of 550°C in still air cooling and the samples were taken out immediately for water quenching. It was found that heat treatment cycles should be limited to 3 cycles or less in order to maintain fine grain size and globular structure without agglomeration and coalescence. Cyclic semi-solid heat treatment changes morphology of iron-rich intermetallics phases to be plate-like and fine plate iron-rich intermetallics phases, in stead of needle-like iron-rich intermetallics phases that are observed in as-cast samples. Cyclic heating shows a relatively higher hardness for all heating cycles compared with as-cast one due to its finer and globular structure. Cyclic semi-solid heat treatment technique results in lower coarsening rate constant compared with isothermal heat treatment one due to coarsening discontinuous effect. 展开更多
关键词 Microstructural CYCLIC SEMI-solid Heat treatment Al-18% SI Microstructure Hyper-Eutectic CAST
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