40 resultados para RB-85


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利用102MeV的28Si束流,通过60Ni(28Si,2pn)熔合蒸发反应布居了85Zr核的高自旋态,测量了γ-γ符合及DCO比值,建立了一个有43条能级,75条γ跃迁的能级纲图,新增加了36条γ跃迁,25条能级.将能级自旋推高到(49/2+),首次观察到了转晕带的第二回弯.并确认了一条建立在17/2-负宇称带上的磁转动带.

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<正>质量数80区的过渡性核表现了集体性和单粒子性的能级结构。对质子数Z为37~40、中子数N=45的原子核,如81Kr,87Mo核,在中低自旋时显示了单粒子特性,而在高自旋态时表现出较多的集体性。 近些年来,在过渡区在束γ谱学,如83Rb、83Y等核研究中,观察到了一串建立在较高K态的增强的△I=1的M1跃迁。它被认为是一种新的激发模式,叫做磁转动带。我们对85Zr的研究目的,一是将其能级推到更高自旋,另一个是寻找该核的磁转动带。

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In this letter, a simple and versatile approach to micropatterning a metal film, which is evaporated on a Si substrate coated with polymer, is demonstrated by the use of a prepatterned epoxy mold. The polymer interlayer between the metal and the Si substrate is found important for the high quality pattern. When the metal-polymer-Si sandwich structure is heated with the temperature below T-m but above T-g of the polymer, the plastic deformation of the polymer film occurs under sufficiently high pressure applied. It causes the metal to crack locally or weaken along the pattern edges. Further heating while applying a lower pressure results in the formation of an intimate junction between the epoxy stamp and the metal film. Under these conditions the epoxy cures further, ensuring adhesion between the stamp and the film. The lift-off process works because the adhesion between the epoxy and the metal film is stronger than that between the metal film and the polymer. A polymer field effect transistor is fabricated in order to demonstrate potential applications of this micropatterning approach.

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本文系统地研究了化合物ASm_2I_5(A=K,Rb,Cs,T1)固体粉末的荧光光谱和反射光谱.讨论了Sm~(2+)在立方晶体场中的分裂能随着碱金属离子半径的增大而减小和f-d激发能随着A-I(A=Rb,T1)键的共价性增加而明显降低的现象.并从晶场效应和化学键性质两个方面解释了ASm_2I_5(A=K,Rb,Cs)和ASm_2I_5(A=Rb,T1)中的Sm~(2+)荧光光谱分别发生蓝移和红移的现象.

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Using knowledge of geology, geochemistry, coal petrology, mineralogy, by means of a variety of advanced measuring methods such as inductively coupled plasma mass spectrometry (ICP-MS), inductively coupled atomic emission spectrometry (ICP-AES), X-ray powder diffraction (XRD), scanning electron microscopy with energy-dispersive spectrometer(SEM-EDS), sequential chemical extract and density fractions, the characteristics of trace elements and minerals in Jurassic Beipiao coal mine under inland limnetic sedimentary environment and in late Permian Jianxin and Qiaotou coal mines under paralic swamp sedimentary environment were studied. Compared with the average concentration in the world bituminous coals, the Beipiao coal was characterized by relatively high contents of Sc, Ti, Cr, Co, Ni, Zn, Se, Sr, Zr, Y, Ba, REE and Th, and lower contents of V, Rb, Cd, Sn, Pb, Bi and U; while the Jianxin coal was relatively enriched in Li, Sc, Ga, Sr, Y, Nb, Sb, Th and U, with low concentration of Be, Co, Ni, Cu, Ge, Zr, Mo, Cd, Cs, Ba, Pb and Bi; and the Qiaotou coal was enriched in Li, Sc, Sr, Nb, Ta, Zr, REE, Hf, Th and U, with low concentration of Be, V, Co, Ni, Cu, Ge, Mo, Cd, Cs, Ba, Tl, Pb and Bi. The concentrations of Ca, Mg and K in Beipiao coal are higher than those in Jianxin coal and Qiaotou coal, while Fe, S and Ti in Beipiao coal are lower than those in Jianxin coal and Qiaotou coal. The proximate analysis of coal samples was carried out, which indicated that Beipiao coal was medium- to high- ash (5.92-60.68%) with low sulphur coal, and Jianxin coal and Qiaotou coal was medium to high ash (8.85-46.33%) with high sulphur. The reflectivity was measured, which explained that Beipiao coal belonged to high volatile bituminous coal, Jianxin coal was low volatile bituminous coal and Qiaotou coal was low volatile anthracite. Quantitative maceral analyses were studied. The characteristics of rare earth elements (REE) were investigated, which showed that the total contents of REE were higher than that of the world's average content. With the increase of coal's metamorphic grade, the total contents of REE decreased from 98.5 X 10"6 of Beipiao coal to 94.2 X 10"6 of Jianxin coal, and to 75.9 X 10"6 of Qiaotou coal, and 5Eu reduced which indicated that the element Eu depleted. The characteristics of REE was controlled by the metamorphic grade of coal. And REE were mainly absorbed in clay minerals in Beipiao coal samples, while in Jianxin and Qiaotou coal mines, REE were primarily related to clay mineral and pyrite. The variation of trace elements in vertical direction of coal seams was studied, and the results showed that different trace elements differed greatly. The correlation between trace elements and ash were determined. Four major trace elements (aluminium-silicates, sulphide, carbonate and phosphate) accounted for the occurrence and distribution of most elements studied were determined. Coal samples were separated by density fraction, which showed that Cr, Cu, Mo and Pb were closely related to inorganic matters mainly distributed in P >2.6 and dropped remarkably in the density fractions P <2.3 . The occurrences of Co, Cr, Ni, As, Se, Mo, U were studied directly and quantitatively using sequential chemical extract with six steps, which showed that Co. Ni, Mo and U were mainly in the form of mineral, and As, Se chiefly in the form of organic state, while Cr mostly in the form of organic state and mineral. Major mineral phases presented in the Beipiao coal were Kaolinite, illite, quartz, calcite, and small amount of siderite, barite. While major mineral phases in Jianxin and Qiaotou coal were pyrite, kaolinite, and small amount of marcasite, rutile, sphalerite. This is the first time that the chromite in the coal was discovered in China, which indicates that Cr occurrence appeared in the form of chromite. The ratio of Sr/Ba, Sr/Ca and V/Ni in Beipiao coal mine under inland limnetic is smaller than that of in Jianxin and Qiaotou coal mines under paralic swamp. The ratio of K/Na and Th/U of Beipiao coal mine is higher than that of Jianxin and Qiaotou coal mine, which proved that Beipiao coal was not affected by sea water and Jianxin and Qiaotou coal were affected by sea water. Trace elements such as Cr, Ni, Mo in minerals were analyzed by SEM-EDS. The factors controlling the enrichment of trace elements can be divided into syngenetic stage factors and epigenetic stage factors.

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位于四川西北部的马脑壳金矿床为陕甘川金三角区内一重要矿床,许多学者对其进行过大量的研究,对其地质地球化学特征有了较为全面的认识,同时对矿床的成因也做了多方面的探讨。为了确定矿床的成矿时代,从层状矿体中采集了富含流体包裹体的石英矿物。通过测定包裹体的Rb-Sr同位素组成,应用ISOPLOT程序计算获得(210±35)Ma的成矿年龄,该年龄与容矿地层的形成时代相近。流体包裹体的锶同位素初始比值与三叠纪时期海水的锶同位素比值相一致。综合矿体产出特征、矿石组构及区域构造演化历史,认为作为矿床主体的层状矿体是同生沉积的产物,脉状网脉状矿体则是由后期造山运动体制下所产生的成矿热流体沿裂隙构造交代充填所形成。