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活图形 编码设绘在船舶手工制图中的应用
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作者 阳大平 《水运科技情报》 1992年第4期10-13,共4页
关键词 活图形 编码设绘 船舶 制图
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EGA/VGA支持的实时能谱图形真正活显问题的彻底解决 被引量:2
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作者 谭亚军 《核电子学与探测技术》 CAS CSCD 北大核心 1992年第6期329-333,共5页
文章提出了EGA/VGA条件下实时能谱图形真正活显问题的解决方法,指出虚拟显示屏及多层缓冲区的概念,以及谱数据光栅化,直接读写视频图形缓冲区是解决问题的关键,并且给出由C语言和宏汇编语言实现的局部示例。
关键词 EGA/VGA 实时能谱图形真正显问题 虚拟显示屏 显示
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Hot deformation behavior of TC11/Ti-22Al-25Nb dual-alloy in isothermal compression 被引量:7
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作者 秦春 姚泽坤 +2 位作者 宁永权 石志峰 郭鸿镇 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2015年第7期2195-2205,共11页
The high-temperature flow behavior of TCll/Ti-22Al-25 Nb electron beam(EB) weldments was investigated by the isothermal compression tests at the temperature of 900-1060℃ and the strain rate of 0.001-10 s-(-1).Bas... The high-temperature flow behavior of TCll/Ti-22Al-25 Nb electron beam(EB) weldments was investigated by the isothermal compression tests at the temperature of 900-1060℃ and the strain rate of 0.001-10 s-(-1).Based on the experimental data,the constitutive equation that describes the flow stress as a function of strain rate and deformation temperature is obtained.The apparent activation energy of deformation is calculated,which decreases with increasing the strain and the value is 334 kJ/mol at strain of 0.90.The efficiency of power dissipation η changes obviously with the variation of deformation conditions.Under the strain rates of 0.01,0.1 and 1 s-(-1),the value of η increases with increasing the true strain for different deformation temperatures.While the value of η decreases with increasing the strain under the strain rates of 0.001 and 10 s-(-1).The optimum processing condition is(t(opi)=1060℃,ε(opi)=0.1 s-(-1)) with the peak efficiency of 0.51.Under this deformation,dynamic recrystallization(DRX) is observed obviously in the microstructure of welding zone.Under the condition of 1060℃ and 0.001 s-(-1),the deformation mechanism is dominated by dynamic recovery(DRV) and the value of η decreases sharply(η=0.02).The flow instability is predicted to occur since the instability parameter ξ(ε)becomes negative.The hot working process can be carried out safely in the domain with the strain rate of 0.001-0.6 s-(-1) and the temperature of 900-1060℃. 展开更多
关键词 dual-alloy hot deformation processing map apparent activation energy MICROSTRUCTURE
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Effects of Co_3O_4 nanocatalyst morphology on CO oxidation:Synthesis process map and catalytic activity 被引量:6
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作者 曾良鹏 李孔斋 +2 位作者 黄樊 祝星 李宏程 《Chinese Journal of Catalysis》 SCIE EI CAS CSCD 北大核心 2016年第6期908-922,共15页
This study focuses on drawing a hydrothermal synthesis process map for Co3O4 nanoparticles with various morphologies and investigating the effects of Co3O4 nanocatalyst morphology on CO oxidation.A series of cobalt-hy... This study focuses on drawing a hydrothermal synthesis process map for Co3O4 nanoparticles with various morphologies and investigating the effects of Co3O4 nanocatalyst morphology on CO oxidation.A series of cobalt-hydroxide-carbonate nanoparticles with various morphologies(i.e.,nanorods,nanosheets,and nanocubes) were successfully synthesized,and Co3O4 nanoparticles were obtained by thermal decomposition of the cobalt-hydroxide-carbonate precursors.The results suggest that the cobalt source is a key factor for controlling the morphology of cobalt-hydroxide-carbonate at relatively low hydrothermal temperatures(≤ 140℃).Nanorods can be synthesized in CoCl2 solution,while Co(NO3)2 solution promotes the formation of nanosheets.Further increasing the synthesis temperature(higher than 140 ℃) results in the formation of nanocubes in either Co(NO3)2 or CoCl2 solution.The reaction time only affects the size of the obtained nanoparticles.The presence of CTAB could improve the uniformity and dispersion of particles.Co3O4 nanosheets showed much higher catalytic activity for CO oxidation than nanorods and nanocubes because it has more abundant Co^(3+) on the surface,much higher reducibility,and better oxygen desorption capacity. 展开更多
关键词 Cobalt oxide nanocatalyst Synthesis process map Morphology effect Catalytic activity Carbon monoxide oxidation
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Determination of dynamic recrystallization parameter domains of Ni80A superalloy by enhanced processing maps 被引量:9
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作者 Guo-zheng QUAN Qiao LIU +2 位作者 Jiang ZHAO Wei XIONG Rui-ju SHI 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2019年第7期1449-1464,共16页
The determination of intrinsic deformation parameters inducing grain refinement mechanism of dynamic recrystallization (DRX) contributes to the relative forming process design. For Ni80A superalloy, the processing map... The determination of intrinsic deformation parameters inducing grain refinement mechanism of dynamic recrystallization (DRX) contributes to the relative forming process design. For Ni80A superalloy, the processing maps were constructed by the derivation of the stress-strain data coming from a series of isothermal compression tests at temperatures of 1273^-1473 K and strain rates of 0.01-10 s^-1. According to the processing maps and microstructural validation, the deformation parameter windows with DRX mechanism were separated in an innovative deformation mechanism map. In addition, the deformation activation energy representing deformation energy barrier was introduced to further optimize such windows. Finally, the enhanced processing maps were constructed and the parameter domains corresponding to DRX mechanism and lower deformation barrier were determined as follows: at ε=0.3, domains: 1296-1350 K, 0.056-0.32 s^-1 and 1350-1375 K, 0.035-0.11 s^-1;at ε=0.5, domains: 1290-1348 K, 0.2-0.5 s^-1 and 1305-1370 K, 0.035-0.2 s^-1;at ε=0.7, domains: 1290-1355 K, 0.042-0.26 s^-1;at ε=0.9, domains: 1298-1348 K, 0.037-0.224 s^-1. 展开更多
关键词 nickel-based superalloy deformation activation energy processing map dynamic recrystallization
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Xenopus Tbx6 mediates posterior patterning via activation of Wnt and FGF signalling
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作者 Xin Lou Panfeng Fang +4 位作者 Shuangwei Li Rui-Ying Hu Klaus-Michael Kuemer Herbert Steinbeisser Xiaoyan Ding 《Cell Research》 SCIE CAS CSCD 2006年第9期771-779,共9页
In vertebrates, the patterning of anterior-posterior (AP) axis is a fundamental process during embryogenesis. Wnt and FGF signalling pathways play important roles in regulating the patterning of embryo AP axis. Mous... In vertebrates, the patterning of anterior-posterior (AP) axis is a fundamental process during embryogenesis. Wnt and FGF signalling pathways play important roles in regulating the patterning of embryo AP axis. Mouse Tbx6 encodes a transcription factor that has been demonstrated to be involved in the specification of the posterior tissue in mouse embryonic body. Here, we prove that morpholino-induced knockdown of XTbx6 impairs posterior development, indicating the requirement of XTbx6 in this process. Meanwhile, gain of XTbx6 function is sufficient to induce ectopic posterior structures in Xenopus embryos. Furthermore, XTbx6 activates the expression of Xwnt8 and FGF8, which are two mediators of posterior development, suggesting a mechanism by which XTbx6 modulates posterior patterning via Wnt and FGF signalling pathway activation. 展开更多
关键词 posterior patterning XTbx6 WNT FGF
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Lexis in Dionysius the Areopagite
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作者 Jose Maria Nieva 《Journal of Literature and Art Studies》 2014年第2期129-136,共8页
In his Commentary on Plato's Phaedo, Damascius establishes a close relation between destination (lexis), divine Justice, and life dignity (kat'aian) of every soul. Among several meanings of destination, the most... In his Commentary on Plato's Phaedo, Damascius establishes a close relation between destination (lexis), divine Justice, and life dignity (kat'aian) of every soul. Among several meanings of destination, the most relevant one is related to the condition of the soul after death. Consequently, the purpose of this paper is to consider how this neoplatonic term is conceived in Dionysius Areopagite. For that purpose, the author will analyze such term widely used in the chapter 7 of Ecclesiastic Hierarchy in which Dionysius deals with the funerary rite and in which the notes of the dionysian eschatology are found. In other words, Dionysius' use of this term combines a spiritual and a metaphysic perspective. The former is part of the representation of the dionysian universe in which even the angels receive the name of lexeis and are distinguished by their never ending movement around the Thearchia; the latter is present among humans as a call to imitate such angelic condition. Such imitation is not possible without the effort needed to behave in agreement with an honorable lifestyle (kat'axian, neoplatonic expression also used by Dionysius) that opens the door to a condition or rank granted to man after death. 展开更多
关键词 NEOPLATONISM DESTINATION dionysian eschatology
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The Het R-binding site that activates expression of pat A in vegetative cells is required for normal heterocyst patterning in Anabaena sp. PCC 7120 被引量:1
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作者 侯圣伟 周芳 +2 位作者 彭珊 高宏 徐旭东 《Science Bulletin》 SCIE EI CAS CSCD 2015年第2期192-201,I0001,共11页
Upon nitrogen step-down, Anabaena sp. PCC 7120 produces semi-regularly spaced heterocysts along filaments. HetR, the master regulator of heterocyst differenti- ation, has been shown to up-regulate hetP and hetZ in dif... Upon nitrogen step-down, Anabaena sp. PCC 7120 produces semi-regularly spaced heterocysts along filaments. HetR, the master regulator of heterocyst differenti- ation, has been shown to up-regulate hetP and hetZ in differentiating heterocysts via specific recognition sites. HetR is also predicted to bind to the promoter of patA, a gene required for heterocyst formation at intercalary positions. Here, we show that HetR binds to the predicted site 5′ from patA. Moreover, (1) deletion of the HetR-binding site greatly diminished the expression ofpatA in vegetative cells as shown with gfp, and (2) complementation of a patA mutant by a replicating plasmid that bears patA is largely prevented by removal of that binding site. In contrast, HetR- binding sites suppressed the expression of alr0202 (a homolog of hetZ) specifically in heterocysts and of alr3234 (a homolog of hetP) in whole filaments. Our results indicate that HetR can regulate gene expression in different modes. 展开更多
关键词 ANABAENA HETEROCYST HetR-binding site PATA
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