998 resultados para Beryllium 10


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本文采用固相反应的方法合成了一系列(Ce,Gd,Mn)MgB_5O_(10)磷光体。观察到合成温度、灼烧时间、原料配比对磷光体的形成和发光亮度有重要影响。X射线衍射分析表明,磷光体结构与LaMgB_5O_(10)相同,属单斜晶系、空间群P2_(1/c)。用EPR确定了磷光体中锰离子为二价。测定了(Ce_(0.2)La_(0.2))MgB_5O_(10),(Gd_(0.7)La_(0.3))MgB_5O_(10),(Mn_(0.05)La_(0.95))MgB_5O_(10),(Ce_(0.2)Mn_(0.05)La_(0.75))MgB_5O_(10),(Gd_(0.95)Mn_(0.05))MgB_5O_(10)、(Ce_(0.2)Gd_(0.8))MgB_5O_(10)和(Ce_(0.2)Gd_(0.75)Mn_(0.05))MgB_5O_(15)等磷光体的光谱。根据光谱数据讨论了(Ce_(0.2)Gd_(0.75)Mn_(0.05))MgB_5O_(10)磷光体中能量传递过程为:Ce~(3+)→Mn~(2+),Gd~(3+)→Mn~(2+)以及Ce~(3+)→Gd~(3+)→Mn~(2+),其中Ce~(...

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在Ar气氛中,采用高温固相反应法合成了K_5LnLi_2F_(10)(Ln=La,Ce,Gd,Y)化合物。X射线衍射图表明:除K_5YLi_2F_(10)外,均具有与K_5NdLi_2F_(10)(KNLF)相同的结构。计算了K_5LnLi_2F_(10)(Ln=La,Ce,Gd)的晶胞参数和晶胞体积,它们随着La~(3+),Ce(3+),Gd~(3+)的离子半径减小而有规律地减小。测定了K_5Ce_?Ln_(1-?)Li_2F_(10)化合物的激发光谱和荧光光谱。发现Ce~(3+)的激发波长和发射波长随着La~(3+),Gd~(3+),Y~(3+)离子的改变几乎不变,并对这种现象进行了讨论。

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C16H15Br2O7.5, orthorhombic, P2(1)2(1)2 (no. 18), a = 18.483(2) angstrom, b = 9.413(1) angstrom, c = 10.072(1) angstrom, V = 1752.3 angstrom(3), Z = 4, R-gt(F) = 0.083, wR(ref)(F-2) = 0.202, T= 293 K.

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The title compound, [ CdCl2( C12H8N2)(2)]center dot 0.5H(2)O, crystallizes with two independent complex molecules and one water molecule in the asymmetric unit. The Cd atoms in both independent complexes display a distorted octahedral coordination geometry formed by four N atoms from two phenanthroline ligands and two Cl atoms. In the crystal structure, pi-pi stacking interactions link complexes in two symmetry- independent ladders parallel to the c axis. Intermolecular O-H center dot center dot center dot Cl hydrogen bonds stabilize the crystal packing.

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The structure of the title compound, [Zn(C8H4O4)(C12H8N2)-(H2O)(3)]center dot H2O, displays a distorted octahedral coordination geometry, with two N atoms from the bidentate phenanthroline ligand, three O atoms from three meridional H2O molecules and one O atom from the monodentate phthalate ion.

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采用反相高效液相色谱梯度洗脱,在SinoChrom ODS-BP型色谱柱(4.6mm×200mm,5μm)上,实现了包括5种荧光衍生试剂母体分子(咔唑、1,2-苯并-3,4-二氢咔唑、吖啶酮、2-苯基-1-氢-菲[9,10-d]咪唑、吡唑并[3,4-b]-7-甲基喹啉)在内的10种含氮芳香化合物的基线分离。通过测定每种物质的紫外吸收曲线,得到了它们的最大紫外吸收波长和摩尔吸光系数(ε),并探讨了分子结构、摩尔吸光系数(ε)和灵敏度之间的关系。扫描了它们的荧光激发和发射光谱,得出了它们的最大激发波长和发射波长。

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合成了新的荧光衍生试剂1-[2-(对甲苯磺酸酯)乙基]-2-苯基咪唑[4,5-f]9,10-菲(TsEPIP),并将其作为柱前衍生化试剂,在Eclipse XDB-C:色谱柱上采用梯度洗脱实现了11种长链(C_(20)~C_(30))游离脂肪酸(FFA)衍生物的基线分离。利用柱后在线的串联质谱并以大气压化学电离源(APCI)的正离子模式实现了各组分的质谱定性。对土壤及3种苔醉(东亚毛灰鲜、锦丝鲜、羽平鲜)中FFA组分的定量结果表明,苔鲜植物从土壤中富集了大量的长链游离脂肪酸。荧光检测的激发波长和发射波长分别为260 nm和380 nm。线性回归系数大于0.9996,检测限为26.19~76.67 fmol。所建立的方法具有良好的重现性,对实际样品的测定结果令人满意。

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对CIMMYT的99份硬粒小麦-节节麦人工合成种(简称合成种)的HMW-GS组成分析发现,Glu-B1和Glu-D1位点的变异类型比普通小麦丰富,分别有9种和12种亚基类型;筛选出含有比5+10亚基更优质的1.5+10和5+12亚基的合成种分别有8份和1份;含有优质亚基1.5+10的合成种与普通小麦杂交结实正常;对2个合成种与2个普通小麦品种的8个止反交组合F1种子电泳发现,优质亚基1.5+10在F1代能正常表达,双亲所有亚基任F1代都得到表达,表现共显性遗传。本研究为优质亚基1.5+10和5+12转育到普通小麦中奠定了基础。

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Rhubarb is an important Traditional Chinese Medicine. However, the wild resource has been declining. In order to design appropriate conservation methods for the official species across their natural distributions, it is important to characterize their genetic diversity. Here, we describe the development of 10 new microsatellite loci for AC/TG/CCA in Rheum tanguticum. The microsatellites were enriched using the combined biotin capture method. The polymorphism of each locus was further assessed in 12 individuals from four geographically distinct populations of this species. The number of alleles ranged from three to seven and the expected heterozygosity ranged from 0.53 to 0.73. All markers have been checked in the other three species in the genus and two of them together comprise the official medicinal rhubarb resource, with R. tanguticum. These microsatellite markers could. provide a useful tool for genetic and conservation studies of the rhubarb species.

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A simple, sensitive, and mild method for the determination of amino compounds based on a condensation reaction with 1-ethyl-3-(3-dimethylaminopropyl)-carbodiimide hydrochloride (EDC-HCI) as the dehydrant with fluorescence detection has been developed. Amines were derivatized to their acidamides with labeling reagent 2-(2-phenyl-1H-phenanthro-[9,10-d]imidazole-1-yl)-acetic acid (PPIA). Studies on derivatization conditions indicated that the coupling reaction proceeded rapidly and smoothly in the presence of a base catalyst in acetonitrile to give the corresponding sensitively fluorescent derivatives with an excitation maximum at lambda(ex) 260nm and an emission maximum at lambda(em) 380nm. The labeled derivatives exhibited high stability and were enough to be efficiently analyzed by high-performance liquid chromatography. Identification of derivatives was carried out by online post-column mass spectrometry (LC/APCI-MS/MS) and showed an intense protonated molecular ion corresponding m/z [MH](+) under APCI in positive-ion mode. At the same time, the fluorescence properties of derivatives in various solvents or at different temperature were investigated. The method, in conjunction with a gradient elution, offered a baseline resolution of the common amine derivatives on a reversed-phase Eclipse XDB-C-8 column. LC separation for the derivatized amines showed good reproducibility with acetonitrile-water as mobile phase. Detection limits calculated from 0.78 pmol injection, at a signal-to-noise ratio of 3, were 3.1-18.2 fmol. The mean intra- and inter-assay precision for all amine levels were < 3.85% and 2.11%, respectively. Excellent linear responses were observed with coefficients of > 0.9996. The established method for the determination of aliphatic amines from real wastewater and biological samples was satisfactory. (c) 2006 Elsevier B.V. All rights reserved.

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Ordos basin is a large-scale craton overlapping basin, which locates in western North China platform and possesses abundant hydrocarbon resources. Ansai area in 2007 to extend the head of Chang10 of Yangchang Formation has made breakthrough progress in the region, long a high of Gao52 was Chang10 industrial oil flow, for oil exploration Ansai Oil Field opened a new chapter. in 2008, high of Gao52, Wang519, Gao34 producing wells area of building and found the existence of Chang10 great potential for the discovery of Chang10 Reservoir, Ansai Oil Field for a new direction, showing a good exploration development prospects.The study of occurrence and distribution features of hydrocarbon should be made by new theories and evolutions of sedimentology, sequence stratigraphy, reservoir sedimentology and petroleum geology form different angles on the base of regional geology background. Ansai Oil Field is in mid Shanbei Slope, which is a considerable producing zone of Ordos basin. Chang10 of Yangchang Formation is an important oil-bearing series, which sedimentary formation was formed in Indosinian orogeny, Late Triassic, sedimentary background is a momentary uplifting in Ordos basin, and exploration and exploitation of hydrocarbon in this area is very important. To further descripte disciplinarian of accumulation hydrocarbon, carefully study on sedimentary facies, reservoir type and disciplinarian of accumulation hydrocarbon of Chang10 of Yangchang Formation in study area is needed. By collecting date of field profile, outcrop, core and many other geological, through sedimentary and oil geological analysis, sedimentary facies types were identified, distributing of sedimentary facies and extension of sand body were analyzed too. Finally, the main controlling factors of hydrocarbon and the favorable areas were found out by deeply studying sedimentary system and disciplinarian of accumulation oil&gas in Chang10 of Yangchang Formation, Late Triassic in Ansai Oil Field. Chang10 of Yangchang Formation is main study formation, which is divided into three members (Chang101, Chang102 and Chang103), Chang101 is subdivided into three (Chang1011, Chang1012and Chang1013) reservoirs. By defining Layered borderline between every member and detailed describing rock and electro characteristic, member zonation become more reasonable and accurate also sedimentary facies and disciplinarian of accumulation oil&gas in study area are confirmed Through researching sedimentary facies, reservoir sand and hydrocarbon migration, accumulation, distribution, hydrocarbon accumulation models of Chang10 of Yangchang Formation in study area is pointed out, which is lithologic hydrocarbon reservoir and tectonic-lithologic hydrocarbon reservoir. Different play is formed by different processes and factors. Through analysis of reservoir property, trap type and accumulation model, several favorable exploration areas can be found out in Chang 10 reservoirs (Chang1011, Chang1012and Chang1013) of the Ansai Oil Field.

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The surface of the Earth is continuously undergoing changes as a result of weathering-erosion, plate tectonics and volcanic processes. Continental weathering-erosion with its complex rock-water interactions is the central process of global biochemical cycling of elements, and affects the long-term ocean atmosphere budget of carbon dioxide both through the consumption of carbonic acid during silicate weathering and through changes in the weathering and burial rates of organic carbon. Rates of the weathering-erosion depend on a variety of factors, in particular rock properties and chemical composition, climate (especially rainfall), structure, and elevation. They are quite variable on a regional scale. Thus, environmental changes in a region could be indicated by the history of weathering-erosion in the region. Recent attention has focused on increased silicate weathering of tectonically uplifted areas in the India-Asia collision zone as a possible cause for falling atmospheric CO_2 levels in the Cenozoic era. The wind blown dust deposits in the Loess Plateau is derived from the arid and semiarid regions in northwestern China, in turn, where the deposits have been derived from the Qinghai-Xizang Plateau and the high mountains around. Therefore, geochemistry of the wind blown loess-paleosol and red clay sequences may provide insight both to paleoenvironmental changes on the Loess Plateau, and to the uplift and weathering-erosion histories of the Qinghai-Xizang Plateau. In this paper, uranium-thorium series nuclides and cosmogenic ~(10)Be have been employed as tracers of weathering intensities and histories of the dust sediments in the Loess Plateau. Major elements, such as Na, Al, Fe etc., are also used to estimate degree of chemical alteration of the dust sediments and to rebuild the history of weathering on the Loess Plateau. First of all, using a low-level HPGe γ-ray detector, we measured U and Th series nuclides in 170 loess and paleosol samples from five sites in the Loess Plateau, going back 2.6 Ma. The results show that ~(238)U activities are disequilibrium with its daughter nuclide ~(230)Th in young loess-paleosol sequence, indicating that weathering was happened both in dust deposition site and in dust source regions. Using concentrations of ~(238)U and ~(232)Th in the samples, we estimated the amounts of ~(238)U leached out of from paleosols due to weathering. Further, based on analyses of ~(230)Th in paleosols deposited in the past ca. 140 ka, we determined when the paleosols weathered in the source regions. We conclude that most of the weathering in the dust-source regions may have occurred during the interglacials before dust deposition.

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The foundation of reservoir model and residual oil prediction have been the core of reservoir detailed description for improved oil production and enhanced oil recovery. The traditional way of sandstone correlation based on the geometrical similarity of well-logs which emphasizes "based on the cycle and correlating from larger to smaller" has shown its theoretical limits when explaining the correlating and the scale, geometry, continuity, connectivity of sandstones and the law of the reservoir property. It has been an urgent and difficult subject to find new theory and methods to solve the reservoir correlation and property prediction. It's a new way to correlate strata and found framework of reservoir through the process-response analysis in the base-level cycles. And it is also possible to analyze the reservoir property in reservoir framework. Taking the reservoir of zonation 6-10 in S3~2 of Pucheng Oil Field in Henan Province as an example, we founded the detailed reservoir stratigraphic framework through base-level correlation. In the strata frame, sediment distribution and its development are discussed based on sediment volume partitioning and facies differentiation analysis. Reservoir heterogeneities and its relation to base-level are also discussed. The analysis of primary oil distribution shows the base-level controlled oil distribution in reservoir. In this paper, subjects as following are discussed in detail. Based on the analysis of sedimentary structure and sedimentary energy, the facies model was founded. Founding stratigraphy framework through base level analysis In the studying zone, one long term cycle, 6 middle term cycles and 27 short term cycles was identified and correlated. 3 Predicting the property of reservoir for improving oil development The base level controlled the property of sandbody. The short and very short term cycle controlled the pattern of heterogeneities in sandbody, and the middle and long term cycle controlled the area and inter-layer heterogeneities. On the lower location of the middle and long term base level, the sandbody is well developed, with a wide area and large thickness, while on the high location of base level, there is an opposite reservoir character. 4 The studying of reservoir development response and oil distribution making a solid base for development adjustment Primary oil distribution is controlled by base level location. It tells that the sandbody on the high base level location was poor developed for its difficulty to develop. While on the low location of the base level, the sandbody is well developed for its relative easy to develop and dominant role in the development, but high residual oil for its high original oil content.