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catalytic nucleation of a meta-stable δ phase in phase-seeded undercooled Fe75Ni25 melts

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Progress in Natural Science:Materials International 2012年第3期22卷 258-262页

作者： y.Z. chen, X.H. Shi, F. Liu, G.c. yang, y.H. Zhou State Key Laboratory of Solidification Processing, Northwestern Polytechnical University, Xi’an, Shaanxi 710072, china State Key Laboratory of Solidification Processing Northwestern Polytechnical University Xi’an Shaanxi 710072 China

Undercooled Fe75Ni25 melts were phase-seeded by a high purity iron. It was found that above a critical undercooling, △Tc 135 K, a metastable δ phase (b.c.c) solidifies from the iron-seeded melts instead of a thermodynamically stable γ phase (f.c.c). While undercooling of the melt (△T) is below △Tc, solidification of the γ phase prevails in the iron-seeded melts. For the undercooled melts subjected to spontaneous nucleation, the γ phase always solidifies. After solidification, the as-solidified γ phase transforms completely to martensite; whereas the as-solidified metastable δ phase partially transforms to the γ phase, and then to martensite. The untransformed δ phase retains as a-ferrite particles in the microstructures. Based on the classical nucleation theory, catalytic nucleation of the metastable δ phase in the phase-seeded undercooled Fe75Ni25 melts was analyzed. It was quantitatively demonstrated that when △T>△Tc, the formation of the δ phase can be ascribed to a better catalytic effect of the iron on its nucleation than that on the nucleation of the γ phase.

关键词： Iron-nickel alloy Rapid solidification Microstructure Nucleation Undercooling

GRAIN REFINEMENT IN BULK HyPERcOOLED Ni_(50)cu_(50) ALLOy

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Acta Metallurgica Sinica(English Letters) 2000年第3期13卷 843-848页

作者： G.S. Song Z.Z. Zhang X.B. Dong, G.c. yang and y.H. Zhou(State Key Laboratory of Solidification Processing, Northwestern Polytechnical University, Xi’an 710072,china) Northwestern Polytechnical Univ Xi'an China

Undereooling eoperiments on binary Ni50 cu50 alloy melts were conducted. The hypercooling limit of this alloy, which is about 310K, was evaluated by mcasuring plateau time needed for the interkendritic liquid solidification and extmpolating this function to zero. This limit was exceeded first in the binary alloy undereooled by about *** effect of liquid undercooling on the respective microstructure evolution was studied by optical metallogrnphy. The hypercooled microstructure contains rcsidual fragments within grain boundaries and is quite different from those obtained at undercoolings below 310K. The finding indicated the existence of dendrite break up. The dendrite break up may be induced either by remelting or by stress. By considering hyperrooling conditions and comparing two grain ndnement microstructures observed at small and larpe undereoolings, the forms of dendrite break up and the grain refinement mechanism exceeding the hypereooling limit are further discussed.

关键词： hypercooling grain refinement dendrite break up Ni_(50)cu_(50) alloy

Gene SGL,encoding a kinesin-like protein,is involved in grain length and plant height in rice

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Gene SGL,encoding a kinesin-like protein,is involved in grai...

Decagonal quasicrystal growth in the undercooled A172Ni12co16 alloy

2013全国植物生物学大会

作者： WU T SHEN y y ZHENG M yang c y cHEN y L FENG Z M LIU X LIU S J cHENG Z J LEI c L WANG J L JIANG L WAN J M State Key Laboratory for crop Genetics and Germplasm Enhancement Jiangsu Plant Gene Engineering Research CenterNanjing Agricultural University National Key Facility for crop Gene Resources and Genetic Improvement Institute of Crop ScienceChinese Academy of Agricultural Sciences

Grain shape,a complex agronomic trait,plays an important role in determining yield and quality in *** the present study,a mutant named short grain length(sgl) was identified among explants of tiss

关键词： Oryza sativa short grain length kinesin-like protein GA

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Decagonal quasicrystal growth in the undercooled A172Ni12Co1...

移动智能设备的使用对北京市居民多任务购物行为和商业微区位的影响

作者： y.c. Liu~*, X.F. Guo, J.H. yang, G.c. yang, y.H. Zhou State Key Lab of Solidification Processing, Northwestern Polytechnical University, Xi’an 710072. People’s Republic of china

High undercooling of the single-phase decagonal quasicrystal alloy AlNico was achieved by cyclically superheating the melt in a containerless electromagnetic levitation apparatus. The maximum undercooling of it was up to 368 K. XRD, TEM, SEM and optical microscopy techniques were adopted to investigate the microstructure and identify the phase composition, respectively. A distinct roughening transition was detected in the undercooled samples with the undercooling increasing. The decagonal quasicrystal phase in samples with small undercoolings showed a facet morphology and grew in a lateral growth mode below the roughening transition undercooling point, △T = 64 K. Then the decagonal phase took on an equiaxed structure and indicated a continuous growth pattern. The roughening transition was caused by a sudden change of the growth direction from the two-fold axis normal to plane (00002) to the ten-fold axis in the undercooled melt. Toner’s surface dynamics models of growing three-dimensional quasicrystal and BcT growth model in the undercooled melt (proposed by Boettinger, coriel and Trivedi) were adopted to explain the roughening transition phenomenon. 2000 Elsevier Science B.V. All fights reserved.

关键词： Decagonal quasicrystal Lateral growth continuous growth Melt undercooling

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中国科学：地球科学 2018年第3期48卷 353-365页

作者：陈丹杨永春李恩龙史坤博兰州大学资源环境学院兰州大学西部环境教育部重点实验室兰州730000 Department of Geography Ghent UniversityGhent 9000Belgium

信息时代,受信息通信技术(IcTs)浪潮的冲击,消费者购物行为和商业微区位格局可能会被影响.本文基于北京市西单商圈的实地调研,利用单因素方差分析、相关性分析和选择型共栖关联度,探讨移动智能设备的使用对北京市居民多任务购物行为和... 详细信息

信息时代,受信息通信技术(IcTs)浪潮的冲击,消费者购物行为和商业微区位格局可能会被影响.本文基于北京市西单商圈的实地调研,利用单因素方差分析、相关性分析和选择型共栖关联度,探讨移动智能设备的使用对北京市居民多任务购物行为和商业微区位的影响.结果显示:(1)消费者在购物过程中使用移动智能设备进行购物的频率整体偏高,购物出行过程中随时间的推移,使用频率呈现由高向低变化的趋势,功能逐渐由支付变为挑选和查找.(2)移动智能设备的使用频次和消费者意向购物件数总体具有正相关关系,使用移动智能设备更频繁的消费群体的意向购买件数整体上显著多于使用频次较低的消费群体,说明移动智能设备的使用的确能够促进消费者多任务购物行为的产生.(3)从选择型共栖关联度来看,生活必需品间的关联度在所有商品关联度中最高,特别是互补型商品的关联极其显著.(4)对比基于消费者购物选择的商业关联性和西单商圈5个典型购物场所商户结构,发现消费者需求和商户结构间总体呈现出较好的呼应关系,但不同的商业综合体表现出不同的商业关联性,建立时间较晚的商业综合体其商业关联性相对较高,而建立时间较早的商业综合体其商业关联性整体较低.以上结果说明IcTs不仅可以较好地辅助消费者进行购物,增加消费者购物多任务化(multi-tasking)趋势,而且会对商业微区位产生潜在影响,未来可能会引导消费者需求与商户供给间关联性较差的商业综合体进行微区位重构,向商品类型的多元化发展.

关键词：信息通信技术多任务购物微区位商业关联性西单商圈北京市

NKX6-1是胰腺及十二指肠神经内分泌肿瘤新的免疫组化标志物

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临床与实验病理学杂志 2015年第8期31卷 899-899页

作者： Tseng I c yeh M M yang c y 胡舜余英豪南京军区福州总医院病理科福州350025

Tseng I c, yeh MM, yangcy, etal. NKX6-1 isanovelim- munohistochemical marker for pancreatic and duodenal neuroen- docrine tumors. Am J Surg Pathol, 2015,39（6）：850 -7.胃肠道神经内分泌肿瘤分为高分化神经内分泌肿瘤（WDNETs）及低分化神经内分泌癌（PDNEcs），前者通常进行手术切除和（或）分子靶向治疗，而PDNEcs通常采用化疗。NKX6-1是一种同源框转录因子，参与胰岛内分泌功能的发生和调节。

关键词：神经内分泌肿瘤免疫组化标志物十二指肠胰腺 marker 神经内分泌癌分子靶向治疗内分泌功能

湖北鄂城“发红”田施磷效果和缺磷原因的研究

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土壤学报 1965年第1期 18-23页

作者：杨补勤王庆云梁琼玉李安华中农学院

据目前了解,发育在湖北省第四纪红色粘土和褐色粘土沉积物上的水稻土,有相当面积的“发红”田,但各地名称不一。如在京山一带称为瘦遨疳田,江陵一带称为红斑瘘,宜都一带称为火坑田,襄阳一带称为地火田,鄂城一带称为澿水田等。从全省肥... 详细信息

据目前了解,发育在湖北省第四纪红色粘土和褐色粘土沉积物上的水稻土,有相当面积的“发红”田,但各地名称不一。如在京山一带称为瘦遨疳田,江陵一带称为红斑瘘,宜都一带称为火坑田,襄阳一带称为地火田,鄂城一带称为澿水田等。从全省肥料试验网施磷的效果来看,可以肯定水稻发红是由于土壤磷素营养缺乏所引起的。

关键词：过磷酸钙粘土沉积物水稻土磷素营养泥块泡水稻田土壤耕作土壤中稻水稻黄泥田施磷缺磷湖北

Highly conductive and stable iodine doped argyrodite electrolyte for all-solid-state lithium batteries

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Journal of Energy chemistry 2025年第1期100卷 50-58页

作者： Gaozhan Liu Jing Zhang Jing yang Jinghui chen Xingyue Xiao Xiayin yao Ningbo Institute of Materials Technology and Engineering Chinese Academy of Sciences center of Materials Science and Optoelectronics Engineering University of Chinese Academy of Sciences

Lithium argyrodites with high ionic conductivity and low cost are considered as one of the most prospective solid electrolytes for all-solid-state lithium ***,the poor chemical stability and compatibility with lithium metal limit their ***,Li5.4PS4.4cl1.4I0.2solid electrolyte with high ionic conductivity of 11.49 m S cm-1and improved chemical stability is synthesized by iodine *** ultra-thin Li5.4PS4.4cl1.4I0.2membrane with thickness of 10μm can be obtained by wet coating process,exhibiting a high ionic conductivity of 2.09 mS cm-1and low areal resistance of 1.17Ω***,iodine doping could in-situ form LiI at the lithium/electrolyte interface and improve the critical current density of Li5.4PS4.4cl1.6from 0.8 to 1.35 mA *** resultant LicoO2/Li5.4PS4.4cl1.4I0.2/Li battery shows excellent cycling stability at 1 c,with a reversible specific capacity of 110.1 mA h g-1and a retention of 80.5% after 1000 *** addition,the assembled LicoO2/Li5.4PS4.4cl1.4I0.2membrane/Li pouch cell delivers an initial discharge capacity of 110.4 mA h g-1and 80.5% capacity retention after 100 cycles.

关键词： Argyrodite electrolytes Iodine doping Ionic conductivity Stability All-solid-state lithium battery

全球227个国家和地区贸易网络数据集(1985–2015)

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全球变化数据学报（中英文） 2019年第3期3卷 227-233,337-343页

作者：蒋小荣杨永春汪胜兰湖北文理学院资源环境与旅游学院襄阳441053 兰州大学资源环境学院兰州730000

基于联合国贸易和发展大会(United Nations conferenceon Trade and Development,UNcTAD)发布的全球各国双边货物贸易基础数据,通过Ucinet计算各节点中心度、结构熵等指标,研究了1985–2015年(5个截面)全球227个国家和地区贸易网络的空... 详细信息

基于联合国贸易和发展大会(United Nations conferenceon Trade and Development,UNcTAD)发布的全球各国双边货物贸易基础数据,通过Ucinet计算各节点中心度、结构熵等指标,研究了1985–2015年(5个截面)全球227个国家和地区贸易网络的空间格局及演化特征,得到了《227个国家和地区贸易网络数据集(1985–2015)》。数据结果表明,全球贸易网络的社团演化经历了发达国家主导、亚洲崛起的萌芽、亚洲社团的分离和"三足鼎立"四个阶段。该数据集包括结果数据和附表过程数据,其中结果数据包括:(1)1985、1995、2005、2009和2015年5个年度的全球贸易网络邻接矩阵数据;(2)1985年和2015年全球主要国家网络结构熵值;(3)2015年全球贸易网络Top1、Top2联系流数据。过程数据包括UNcTAD数据库下载的双边进口、出口的原始数据。数据集存储为.xlsx格式,数据量为11.4 MB(压缩后8.7 MB)。该数据集的研究成果发表在《地理研究》2018年第37卷第3期。

关键词：全球贸易网络网络矩阵结构熵地理研究