检索结果-南通市图书馆

Chemical and mechanical properties of stainless, environment-friendly, and nonflammable Mg alloys (SEN alloys): A review

引用

Journal of Magnesium and Alloys 2024年第3期12卷 841-872页

作者： Jong Un Lee Hyun Ji Kim Sang-Cheol Jin ye Jin Kim Young Min Kim Bong Sun You Jun Ho Bae sung Hyuk Park Advanced Metals Division Korea Institute of Materials ScienceChangwon 51508Republic of Korea Department of Materials Science and Metallurgical Engineering Kyungpook National UniversityDaegu 41566Republic of Korea Missile Research Institute Agency for Defense DevelopmentDaejeon 34060Republic of Korea

This review article provides overall understanding of stainless,environment-friendly,and nonflammable Mg alloys(SEN alloys)recently developed at the Korea Institute of Materials *** alloys are produced by adding small amounts of Ca and Y(eachyer of SEN alloys comprising MgO,CaO,and Y_(2)O_(3) impedes the outward dispersion of Mg vapor and the inward penetration of O_(2) during oxidation,thereby enhancing the oxidation and ignition resistances.(2)The presence of Ca-and Y-based second-phase particles in SEN alloys can enhance their corrosion resistance because Ca-containing particles prevent the spread of corrosion,and the replacement of Al-containing particles with less noble ones containing Y(e.g.,Al–Mn–Y or Al–Y particles)retards corrosion.(3)The addition of minor amounts of Ca and Y renders excellent mechanical properties due to improved strengthening *** enhanced properties are attributed to more pronounced dynamic recrystallization and grain refining behaviors caused by the second-phase particles during extrusion.(4)Despite the presence of various types of second-phase particles,the fatigue properties of SEN9 alloys are similar to those of commercial AZ91 alloys.(5)Simultaneous introduction of Ca and Y suppresses the formation of Mg17Al12 discontinuous precipitates during aging,leading to the enhanced elongation of aged SEN alloys.(6)Adding mischmetal into the SEN9 alloy leads to a six-fold enhancement in ***,the studies conducted on SEN alloys demonstrate their excellent ignition and corrosion resistances and mechanical properties,which broaden the industrial applications of Mg alloys by addressing their inherent weaknesses.

关键词： SEN magnesium alloy Corrosion resistance Ignition resistance Mechanical properties Extrudability.

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Gastric inverted hyperplastic polyp: A rare cause of iron deficiency anemia

引用

World Journal of Gastroenterology 2016年第15期22卷 4066-4070页

作者： Jin Tak Yun Seung Woo Lee Dong Pil Kim Seung Hwa Choi Seok-Hwan Kim Jun Kyu Park Sun Hee Jang Yun Jung Park ye gyu sung Hae Jung Sul Division of Gastroenterology Department of Internal Medicine College of Medicine Daejeon St. Mary’s Hospital The Catholic University of Korea Department of Pathology College of Medicine Daejeon St. Mary’s Hospital The Catholic University of Korea

Gastric inverted hyperplastic polyp(IHP) is a rare gastric polyp characterized by the downward growth of hyperplastic mucosal components into the submucosal layer. Macroscopically, a gastric IHP resembles a subepithelial tumor(SET); as a result, accurately diagnosing gastric IHP is difficult. This issue has clinical significance because gastric IHP can be misdiagnosed as SET or as malignant neoplasm In addition, adenocarcinoma can accompany benign gastric IHP. Although in most cases, gastric IHPs are asymptomatic and are found incidentally, these polyps may cause anemia secondary to chronic bleeding. Here, we report one case involving gastric IHP accompanied by chronic iron deficiency anemia that was successfully managed using endoscopic submucosal dissection.

关键词： Stomach Hyperplasia Polyp Anemia

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Acceleration of aging behavior and improvement of mechanical properties of extruded AZ80 alloy through(10–12) twinning

引用

Journal of Magnesium and Alloys 2023年第2期11卷 671-683页

作者： Hyun Ji Kim ye Jin Kim sung Hyuk Park School of Materials Science and Engineering Kyungpook National UniversityDaegu 41566Republic of Korea

The effects of pre-existing {10–12} extension twins on the precipitation behavior of an extruded AZ80 material during aging and on its mechanical properties after peak aging are investigated. The material containing {10–12} twins-which are formed by compression before aging(twinned material)-has a finer grain size and higher dislocation density than the extruded material. Although the peak hardnesses of the twinned and extruded materials are almost the same, the time to reach the peak hardness is considerably shorter in the former material than in the latter(4 h and 24 h, respectively). In the twinned material, the high dislocation density of the {10–12} twins promotes continuous precipitation, which results in the formation of numerous fine Mg17Al12precipitates within the twins in the early stage of *** formation of these continuous precipitates reduces the driving force for discontinuous precipitation, which consequently suppresses the formation and growth of coarse Mg17Al12precipitates at the grain boundaries. Despite its shorter peak-aging time, the 4 h-peak-aged twinned material shows higher tensile strength and elongation than the 24 h-peak-aged extruded material. These higher mechanical properties of the former material are attributed primarily to the presence of more abundant fine continuous precipitates, which are effective in strengthening the material, and less abundant coarse discontinuous precipitates, which can act as crack initiation sites. These results demonstrate that the introduction of {10–12} twins into wrought Mg–Al-based alloys can accelerate the Mg17Al12precipitation kinetics considerably and improve the strength and ductility of the peak-aged alloys simultaneously.

关键词： AZ80 alloy Twin Aging Precipitation Tensile properties

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

兴于微言——从几首小词谈士人修养

引用

南开学报（哲学社会科学版） 2024年第3期 19-29页

作者：叶嘉莹南开大学中华诗教与古典文化研究所天津300071

词这种文学体式自产生之初,便是配合当时的流行音乐演唱的歌词,既没有言志价值也没有载道理想,却因“双重性别”与“双重语境”的作用而形成了一种特殊的美感特质,能够给读者以丰富的联想。随着词体本身的演进,词的观念也在不断演进,通... 详细信息

词这种文学体式自产生之初,便是配合当时的流行音乐演唱的歌词,既没有言志价值也没有载道理想,却因“双重性别”与“双重语境”的作用而形成了一种特殊的美感特质,能够给读者以丰富的联想。随着词体本身的演进,词的观念也在不断演进,通过苏轼、辛弃疾、张惠言、陈曾寿、吕碧城、沈祖棻等人的几首词,可以读出小词中体现的士人修养。

关键词：词双重性别双重语境士人修养

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Microstructural evolution of pre-twinned Mg alloy with annealing temperature and underlying boundary migration mechanism

引用

Journal of Magnesium and Alloys 2023年第8期11卷 2953-2966页

作者： ye Jin Kim Jong Un Lee Gyo Myeong Lee sung Hyuk Park School of Materials Science and Engineering Kyungpook National UniversityDaegu 41566Republic of Korea

This study investigates the variations in the microstructural characteristics of a pre-twinned Mg alloy with the temperature of the subsequent annealing *** this end,a rolled AZ31 alloy is compressed to 3%plastic strain along the rolling direction(RD)to activate{10-12}twinning and is subsequently annealed at 200,250,300,350,and 400℃.Numerous{10-12}twins are formed throughout the compressed material,leading to the formation of a RD-oriented *** an annealing temperature of 200℃,no microstructural variations occur during *** the annealing temperature increases from 250 to 400℃,the residual strain energy and remaining twin boundaries of the annealed material decrease owing to the promoted static recovery and the increased area fraction of twin-free grown ***,an increase in the annealing temperature results in a gradual microstructural transition from a fully twinned grain structure to a completely twin-free grain *** microstructural evolution during annealing is predominantly governed by the movement of high-angle grain boundaries via a strain-induced boundary migration mechanism,and a few twin boundaries migrate above 350℃because of their lower boundary *** boundary migration behavior and resultant microstructural evolution are discussed in detail based on the variations in boundary mobility and driving force for boundary migration with annealing temperature.

关键词： Rolled Mg alloy {10-12}twin Grain growth Boundary migration Annealing

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Microstructural evolution and grain growth mechanism of pre-twinned magnesium alloy during annealing

引用

Journal of Magnesium and Alloys 2021年第4期9卷 1238-1251页

作者： ye Jin Kim Jong Un Lee Young Min Kim sung Hyuk Par School of Materials Science and Engineering Kyungpook National JJniversityDaegu 41566Republic of Korea Implementation Research Division Korea Institute of Materials ScienceChanson 51508Republic of Korea

The microstructural evolution and underlying grain growth mechanism of a{1012}-twin-containing Mg alloy during annealing are investigated through quasi in situ electron backscatter diffraction measurements of a rolled AZ31 alloy subjected to precompression along the rolling direction(RD).The precompressed material shows a partially twinned structure consisting of a twinned region and a residual matrix region,and this structure changes to an almost twin-free structure consisting of grown grains with serrated grain boundaries in twinand matrix-originated regions after annealing at 250℃ for 1 *** addition,the average grain size almost doubles and the internal strain energy decreases significantly after *** microstructural variations are induced mainly by grain growth through the strain-induced migration of high-angle grain boundaries without the movement of twin *** twinned region of the precompressed material has higher stored strain energy than the residual matrix region because the crystallographic orientation of the former region is favorable for basal slip and because of the occurrence of the dislocation transmutation reaction in the *** reducing the total strain energy accumulated in the precompressed material,the residual matrix region—having lower stored strain energy—preferentially grows while consuming the twinned regions formed in the surrounding grains during *** a result,the area fraction of grains with a matrix texture increases whereas that of grains with a twin texture decreases after *** twin texture intensity increases significantly and this texture becomes more concentrated along the RD because the highly RD oriented twins tend to grow during annealing on account of their fairly low stored strain energy.

关键词： Magnesium Twin Annealing Grain growth Strain energy

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Effect of preparation method of noble metal supported catalyts on formaldehyde oxidation at room temperature: Gas or liquid phase reduction

引用

Journal of Environmental Sciences 2022年第12期34卷 201-216页

作者： Younghee Jang ye Hwan Lee Hanki Eom Sang Moon Lee sung Su Kim Department of Environmental Energy Envineering Graduate School of kyonggi UniversityGyeonggi-do 16227Korea Department of Environmental Energy Engineeing Kyonggi UniversityGyonggi-do 16227Korea

Formaldehyde(HCHO) is toxic to the human body and is one of the main threats to the indoor air quality(IAQ). As such, the removal of HCHO is imperative to improving the IAQ,whereby the most useful method to effectively remove HCHO at room temperature is catalytic oxidation. This review discusses catalysts for HCHO room-temperature oxidation,which are categorized according to their preparation methods, i.e., gas-phase reduction and liquid-phase reduction methods. The HCHO oxidation performances, structural features,and reaction mechanisms of the different catalysts are discussed, and directions for future research on catalytic oxidation are reviewed.

关键词： Formaldehyde Indoor air quality Catalyst Prepared method

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Immunotherapy for pancreatic cancer

引用

World Journal of Clinical Cases 2021年第13期9卷 2969-2982页

作者： Jai Hoon Yoon ye-Ji Jung sung-Hoon Moon Department of Internal Medicine Hanyang University College of MedicineSeoul 04763South Korea Department of Internal Medicine Hallym UniversityAnyang 14068South Korea Department of Internal Medicine University of Hallym College of MedicineHallym University Sacred Heart HospitalAnyang 14068South Korea

Pancreatic cancer, a highly lethal cancer, has the lowest 5-year survival rate forseveral reasons, including its tendency for the late diagnosis, a lack of serologicmarkers for screening, aggressive local invasion, its early metastaticdissemination, and its resistance to chemotherapy/radiotherapy. Pancreaticcancer evades immunologic elimination by a variety of mechanisms, includinginduction of an immunosuppressive microenvironment. Cancer-associatedfibroblasts interact with inhibitory immune cells, such as tumor-associatedmacrophages and regulatory T cells, to form an inflammatory shell-like desmoplasticstroma around tumor cells. Immunotherapy has the potential to mobilizethe immune system to eliminate cancer cells. Nevertheless, althoughimmunotherapy has shown brilliant results across a wide range of malignancies,only anti-programmed cell death 1 antibodies have been approved for use inpatients with pancreatic cancer who test positive for microsatellite instability ormismatch repair deficiency. Some patients treated with immunotherapy whoshow progression based on conventional response criteria may prove to have adurable response later. Continuation of immune-based treatment beyond diseaseprogression can be chosen if the patient is clinically stable. Immunotherapeuticapproaches for pancreatic cancer treatment deserve further exploration, given theplethora of combination trials with other immunotherapeutic agents, targetedtherapy, stroma-modulating agents, chemotherapy, and multi-way combinationtherapies.

关键词： Pancreatic adenocarcinoma Pancreatic cancer Immunotherapy Immune checkpoint inhibitor

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Extrusion limit diagram of AZ91–0.9Ca–0.6Y–0.5MM alloy and effects of extrusion parameters on its microstructure and mechanical properties

引用

Journal of Magnesium and Alloys 2022年第12期10卷 3447-3458页

作者： Dong HeeLee ye Jin Kim Sang-Hoon Kim Byoung Gi Moon sung Hyuk Park School of Materials Science and Engineering Kyungpook National UniversityDaegu 41566Republic of Korea Agency for Defense Development Daejeon 34186Republic of Korea Advanced Metals Division Korea Institute of Materials ScienceChangwon 51508Republic of Korea

An AZ91–0.9Ca–0.6Y–0.5MM(AZXWMM91100) alloy, which has higher corrosion resistance, ignition resistance, and extrudability than a commercial AZ91 alloy, has been developed recently. In this study, the AZXWMM91100 alloy is extruded at various temperatures(300–400 ℃) and ram speeds(1–14.5 mm/s), and the cracking behaviors, microstructure, and tensile properties of the extruded materials are systematically analyzed. On the basis of the pressure limit and surface and internal cracking limit, the extrusion limit diagram providing a safe extrusion processing zone is established. All of the materials extruded at temperatures and speeds within the safe extrusion processing zone have high surface quality and moderate tensile ductility with an elongation higher than 10%. Moreover, they have a fully recrystallized grain structure and contain undissolved particle stringers arranged parallel to the extrusion direction. The grain size of the extruded material does not show any relationship with the Zener–Hollomon parameter(Z). However, the yield strength(YS) of the extruded material is inversely proportional to the logarithm of the Z value, and their relationship is expressed as YS =-31.2·log(Z) + 536. These findings may broaden the understanding of the AZXWMM91100 alloy with excellent chemical and physical properties and provide valuable information for the development of high-performance extruded Mg products using this alloy.

关键词： Magnesium Extrudability Extrusion limit diagram Microstructure Tensile properties

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Microstructural characteristics and low-cycle fatigue properties of AZ91 and AZ91-Ca-Y alloys extruded at different temperatures

引用

Journal of Magnesium and Alloys 2023年第3期11卷 892-902页

作者： ye Jin Kim Young Min Kim Jun Ho Bae Soo-Hyun Joo sung Hyuk Park School of Materials Science and Engineering Kyungpook National UniversityDaegu 41566Republic of Korea Advanced Metals Division Korea Institute of Materials ScienceChangwon 51508Republic of Korea Department of Materials Science and Engineering Dankook UniversityCheonan 31116Republic of Korea

The commercial AZ91 alloy and nonflammable SEN9(AZ91-0.3Ca-0.2Y,wt%)alloy are extruded at 300°C and 400°*** microstructure,tensile and compressive properties,and low-cycle fatigue(LCF)properties are investigated,with particular focus on the influence of the extrusion *** the AZ91 and SEN9 materials extruded at 300°C(300-materials),numerous fine Mg_(17)Al_(12)particles are inhomogeneously distributed owing to localized dynamic precipitation during extrusion,unlike those extruded at 400°C(400-materials).These fine particles suppress the coarsening of recrystallized grains,decreasing the average grain size of *** the four extruded materials have considerably different microstructures,the difference in their tensile yield strengths is insignificant because strong grain-boundary hardening and precipitation hardening effects in 300-materials are offset almost completely by a strong texture hardening effect in ***,owing to their finer grains and weaker texture,300-materials have higher compressive yield strengths *** the LCF tests,{10-12}twinning is activated at lower stresses in 400-materials than in *** the fatigue damage accumulated per cycle is smaller in 400-materials,they have longer fatigue lives than those of 300-materials.A fatigue life prediction model for the investigated materials is established on the basis of the relationship between the total strain energy density(ΔW_(t))and the number of cycles to fatigue failure(N_(f)),and it is expressed through a simple equation(ΔW_(t)=10·N_(f)-0.59).This model enables fatigue life prediction of both the investigated alloys regardless of the extrusion temperature and strain amplitude.

关键词： AZ91-Ca-Y Extrusion temperature Microstructure Low-cycle fatigue Fatigue life prediction model

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

欢迎您,

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

请选择保存的检索档案：

请选择收藏分类：

通借通还

欢迎您,

建议与咨询 留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

请选择保存的检索档案： 新增检索档案 确定 取消

请选择收藏分类： 新增自定义分类 确定 取消

通借通还

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

请选择保存的检索档案：

请选择收藏分类：