301 resultados para ER[alpha]
Resumo:
用蒸发中子反应产生~(157)Tb和~(153)Er,收集活性样品,作x, #gamma# 单谱及符合谱测量,对~(157)Yb和~(153)Er的(EC+#beta#~+)衰变进行了研究,给出了~(157)Yb及~(153)Er的衰变纲图,其中~(157)Yb的衰变纲图包括25条新#gamma#射线,分析~(157)Yb的衰变纲图,~(153)Er的衰变纲图包括15条#gamma#射线,并指定出~(153)Er半衰变期值,该值与文献给出值符合得很好。指定了~(153)Er的衰变纲图中能级状况
Resumo:
利用142Nd(16O,5n)153Er和147Sm(16O,6n)157Yb反应并藉助与氦喷嘴快速带传输装置和x(γ) γt-符合测量技术首次建立了153Er和157Yb的(EC/β+)衰变能级纲图。 对153Er的(EC/β+)衰变纲图的分析,得到结果有, 1) 辨认了256.7KeV和634.2KeV的二条低位能级分别为d3/2和d5/2的单质子态。因此,153H0的基态 的形状为球形。在同位素链Ho(Z=67)上,随着中子数的增加,奇质量数Ho核的基态核形状由球形过渡到变形发生在中子数86和88之间。 2) 位于1700.1KeV能级为三粒子态,具有[(πh11/2 νh9/2)1+ νf7/2] , , 的结构特征。 经对157Yb的(EC/β+)衰变纲图分析,得到结果有, 1) 发现了建立在157Tm基态上的Kπ= 转动带的带头部分。用可变转动惯量的三轴行变粒子转子模型对157Tm的转动能谱的计算结果表明,157Tm的基态Kπ= 转动带所对应的形变是三轴形变,相应的形变参数为ε2=0.23,ε4=0.01,γ=35°。给出了随着中子数的增加,奇质量数Tm(Z=69)核的基态核形状由球形过渡到非球形发生在中子数86和88之间。 2) 辨认了一条位于激发能为3502KeV的同质异能态,其寿命>40ns。
Resumo:
介绍了新一代图像处理系统ERMapper及其应用 ,分析了不同空间尺度下影响水土流失的地形因子。针对ERMapper的图像处理功能 ,对地形因子的提取技术进行了初步探讨 ,并取得了一定成果
Resumo:
本研究采用微电极胞外记录技术和微电泳技术探讨了树(左鼠右句)前额叶神经元的电生理及其alpha-2去甲肾上腺素能受体的性质发现:1.树(左鼠右句)前额叶神经元的自发放电以中频(1-10次/秒)为主。2.树(左鼠右句)前额叶存在多模和单模感觉相关神经元。3.树(左鼠右向)前额叶存在clonidine敏感神经元。4.在树(左鼠右向)前额叶多模神经元中,有较高比例的clonidine敏感神经元。本研究提示:树(左鼠右句)前额叶的clonidine敏感神经元大多为单模和多模神经元。推测这些感觉相关神经元的信息处理功能可能与alpha-2受体有关。此外,本研究表明树(左鼠右句)前额叶神经元电活动具有前额叶的特征。
Resumo:
We synthesized methoxy poly(ethylene glycol)-b-poly(alpha,L-glutamic acid) (mPEGGA) diblock copolymer by ring-opening polymerization of N-carboxy anhydride of gamma-benzyl-L-glutamate (NCA) using amino-terminated methoxy polyethylene glycol (mPEG) as macroinitiator. Polyelectrolyte complexation between mPEGGA as neutral-block-polyanion and chitosan (CS) as polycation has been scrutinized in aqueous solution as well as in the solid state.
Resumo:
A series of new rare-earth metal bis(alkyl) complexes [L(1-3)Ln(CH2SiMe3)(2)(THF)(n)] (L-1 = MeC4H2SCH2NC6H4(Ph)(2)P=NC6H2Me3-2,4,6: Ln = Sc, n = 1 (1a); Ln = Lu, n = 1 (1b); L-2 = MeC4H2SCH2NC6H4(Ph)(2)P=NC6H3Et2-2,6: Ln = Sc, n = 1 (2a); Ln = Lu, n = 1 (2b); Ln = Y, n = 1 (2c); L-3 = MeC4H2SCH2NC6H4(Ph)(2)P=(NC6H3Pr2)-Pr-i-2,6: Ln = Sc, n = 0 (3a)) and (LSc)-Sc-4(CH2SiMe3)(2()THF) (4a) (L-4 = C6H5CH2NC6H4(Ph)(2)P=NC6H3Et2-2,6) have been prepared by reaction of rare-earth metal tris(alkyl)s with the corresponding HL1-4 ligands via alkane elimination.
Resumo:
A series of (alpha-diimine)nickel(II) complexes [ArN = C(Nap)C = NAr]NiBr2 (Nap = 1,8-naphthdiyl, Ar = 2,6-Me2C6H3, 3a; Ar = 2,4,6-Me3C6H2 3b; Ar = 2,6-Me-2-4-tBuC(6)H(2), 3c; Ar 2,6-Me-2-4-BrC6H2, 3d; Ar = 2,6-Me-2-4-ClC6H2, 3e; Ar 2,6-iPr(2)C(6)H(3), 3f; Ar = 2,4,6-iPr(3)C(6)H(2), 3g; Ar = 2,6-iPr-4-BrC6H2, 3h) have been synthesized, characterized, and investigated as precatalysts for ethylene polymerization in the presence of modified methylaluminoxane (MMAO).
Resumo:
Silica and Merrifield resin were used as carriers for the support of alpha-diimine nickel(II) precatalysts for ethylene polymerization. The alpha-diimine ligands containing allyl were modified by introducing the reactive Si-Cl end-group, allowing their immobilization via a direct reaction of the Si-Cl groups with the silanols on silica surface or the hydroxyls on the ethanolamine-modified Merrifield resin. The resulting supported alpha-diimine ligands were characterized by analytical and spectroscopic techniques (NMR and Fr-IR).
Resumo:
The Mg-8Gd-0.6Zr-xEr (x = 1, 3 and 5 mass%) alloys were prepared by casting technology, and the microstructures, age hardening behaviors and mechanical properties of alloys have been investigated. Microstructures of the alloys are characterized by the presence of rosette-shaped equiaxed grains. The age hardening behaviors and the tensile properties are enhanced by adding Er element. The maximum aged hardness of Mg-8Gd-0.6Zr-5Er alloy is 97, it is nearly 1.24 times higher than that of Er-free alloy.
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A refined version of the edge-to-edge matching model is described here. In the original model, the matching directions were obtained from the planes with all the atomic centers that were exactly in the plane, or the distance from the atomic center to the plane which was less than the atomic radius. The direction-matching pairs were the match of straight rows-straight rows and zigzag rows-zigzag rows. In the refined model, the matching directions were obtained from the planes with all the atomic centers that were exactly in the plane.
Resumo:
Hollow deoxyribonucleic acid (DNA)/poly-L-lysine (PLL) capsules were successfully fabricated through a layer-by-layer (LbL) self-assembly of DNA and PLL on porous CaCO3 microparticles, followed by removal of templates with ethylenediamine tetraacetic acid disodium salt (EDTA). The enzymatic degradation of the capsules in the presence of alpha-chymotrypsin was explored. The higher the enzyme concentration, the higher is the degradation rate of hollow capsules. in addition, glutaric dialdehyde (GA) cross-linking was found to be another way to manipulate degradation rate of hollow capsules.
Resumo:
A series of novel, colorless, and transparent sot-gel derived hybrid materials Ln-DBM-Si covalently grafted with Ln(DBM-OH)(3)center dot 2H(2)O (where DBM-OH = o-hydroxydibenzoylmethane, Ln = Nd, Er, Yb, and Sin) were prepared through the primary beta-diketone ligand DBM-OH. The structures and optical properties of Ln-DBM-Si were studied in detail. The investigation results revealed that the lanthanide complexes were successfully in situ grafted into the corresponding hybrids Ln-DBM-Si. Upon excitation at the maximum absorption of ligands, the resultant materials displayed excellent near-infrared luminescence.