991 resultados para 11-98


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The excitation functions of elastic scattering proton which were measured with inverse kinematics of elastic resonance scattering reactions in GANIL and MSU have been fitted by the multi-energy level R-matrix theory. The final result shows that the new energy levels order for nucleus N-11 should be 1/2(+), 1/2(-), 5/2(+), 3/2(+), 3/2(-), 5/2(+), 7/2(-), which is consistent with the experimental results of Be-11 (the mirror nucleus of N-11) and the theoretical calculation of N-11 with GCM theory.

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We experimentally investigate the shell effect on the stabilization processes following the multi-electron transfer in slow collisions of Arq+-Ar (q = 6-9, It) The relative cross-section ratios of multi-electron transfer and of the subsequent stabilization with respect to single-electron capture are measured meanwhile compared with the theoretical results predicted by the classical over-barrier model. Our result indicates that the multi-electron transfer is dominant when the projectile charge is large and the subsequent stabilization shows a dramatic variation if the projectile L-shell configuration becomes open. It shows that the subsequent stabilization processes of multiply excited scattering ions have a strong dependence on the projectile shell. (C) 2010 Elsevier BV All rights reserved.

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本硕士沦文籍助兰州重离子加速器国家实验室分离扇聚焦回旋加速器(SFC)提供的重离子束通过全融合蒸发反应产生远离口稳定线的缺中子核素,并用本课题组发展和建立的氦喷嘴快速带传输系统以及多重符合测量装置分离、测量核素来研究其衰变性质。在实验准备期间,曾采用~(252)Cf源进行了氦喷嘴(I-I eje咧央速带传输系统效率的测定。给出了PbI_2,PbCl_2,NaCl三种无机欲添加剂的传输效率,以及传输效率随目标核质量变化的初步结果。而后完成了以下两项物理实验:~(113)Sm的(EC+β~+)衰变纲图和133Pr的同核异能态的研究:用SFC引出的~(40)Ca~(12+)束流轰击96%Ru的浓缩同位素靶,采用氦喷嘴带传输系统和x-γ与γ-γ符合测量方法,首次建议了~(133)Sm的简单的(EC+β~+)衰变纲图并测得了其β衰变半衰期。~(133)Sm是目前发表过(EC+β~+)衰变纲图的最轻的钐(Sm的缺中子核。由于Ru靶中含有~(98-102)Ru的成分,同时产生了~(133)Pr,并首次测定了~(133)Pr 11/2~-同核异能态的寿命为(l.1±0.2)s。为Pr奇A核11/2~-同核异能态的数据作了重要的补充,汇编成Pr奇A核的11/2一同核异能态和与之相关的3/2~+,5/2~+和7/2~+能级的系统性数据。用单粒子模型理论拟合从中提取了~(131,133,135,137)Pr的11/2~-同核异能态的约化跃迁概率的实验值,并与Weisskopf近似估计进行了比较。2.~(93)Pd的β缓发质子衰变:通过~(58)Ni(~(40)Ca,3n2p)反应合成β缓发质了先驱核~(93)Pd,采用氦喷嘴带传输系统加p-γ符合观测到了它的β缓发质子衰李,测得其半衰期为1.3±0.2s。采用统计模型计算拟合了实验测得的口缓发质子能谱和布居到质子发射体子核不同终态的分支比,首次由实验数据出发初步指认了93Pd的基态自旋-宇称为9/2~±。同时与采用Woods-Saxon Strutinsky方法计算~(93)Pd的核位能面得到的结果进行了比较。计算结果支持对~(93)Pd基态自旋一宇称为9/2~+的实验指认。

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The hydroconversion of n-paraffins is a key reaction in hydrodewaxing of lubricating base oil. In this paper, we investigate the performance of Pt/SAPO-11 catalysts for isomerization of n-paraffins by the model compound of n-dodecane. Under this experimental condition, yields of feed isomers as well as cracking products are a function of the total n-dodecane conversion. Primary products are methylundecane while multi-brancheds and cracking products are formed in successive reactions. The result shows that the addition of Sn increases the selectivity for isomerization reaction. The most ideal experimental data for hydroconversion of n-dodecane is that the selectivity of isomerized products gets 90% when conversion of n-dodecane is 90% for the Sn-promoted Pt/SAPO-11 catalyst.

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Naphthene is generally considered difficult to convert in traditional pyrolysis, but the ring rupture becomes fairly easy with the presence of oxygen in the gas phase oxidative cracking of the model compound, cyclohexane. About 86.8% conversion of cyclohexane, 43.7% yield of light alkenes, 6.6% yield of benzene and 14.3% yield of CO could be obtained at 750 degreesC, at which temperature the pyrolysis of cyclohexane was negligible, while at 850 degreesC, the total yield of alkenes, benzene and CO was as high as 80% (50%, 12% and 18%, respectively) with 98% conversion of cyclohexane. The gas phase oxidative cracking process could be run in an autothermal way (cyclohexane/O-2 mole ratio of 0.69-0.8 in theory), which would minimize energy consumption and capital costs of the whole process. CO prevailed in the produced CO, and the yield Of CO2 was always below 1%, which means about 90% Of CO2 emission by fuel burning in pyrolysis would be saved. The gas phase oxidative cracking process appears to be an environmentally benign and efficient route for light alkene production with naphthene rich feedstocks. (C) 2004 Published by Elsevier B.V.

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介绍一种大米中11种氨基甲酸酯类杀虫剂及其代谢产物的多残留快速测定方法。乙腈提取样品中农药,氨基固相萃取柱净化,甲醇和二氯甲烷(v/v,1/99)洗脱。液相色谱柱后衍生荧光检测器检测。对大米样品进行添加回收率实验,分别添加0.1mg/kg、0.5mg/kg、2mg/kg,回收率在71.9% ̄98.2%之间,变异系数为2.78% ̄10.6%。

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介绍一种大米中11种氨基甲酸酯类杀虫剂及其代谢产物的多残留快速测定方法。乙腈提取样品中农药,氨基固相萃取柱净化,甲醇和二氯甲烷(v/v,1/99)洗脱。液相色谱柱后衍生荧光检测器检测。对大米样品进行添加回收率实验,分别添加0.1、0.52、mg/kg,回收率在71.9%~98.2%,变异系数为2.78%~10.6%。

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本文介绍一种大米中11种氮基甲酸酯类杀虫刺及其代谢产物的多残留快速测定方法。乙腈提取样品中农药,氨基固相萃取柱净化,甲醇和二氯甲烷(v/v,1/99)洗脱。液相色谱柱后衍生荧光检测器检测。对大米样品进行添加回收率实验,分别添加0.1mg/kg、0.5mg/kg、2mg/kg,回收率在71.9~98.2%之间,变异系数为2.78~10.6%。

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MnAPO-11 and MnAPSO-11 were synthesized hydrothermally, and supported Mn-AlPO-11 and Mn-SAPO-11 were also prepared for comparison. Characterization results showed that there were differences in acidity and reducibility caused by the different incorporation methods of manganese. The manganese species in the samples also weakened the metallic properties of the palladium particles when the latter was added into the catalysts. Catalytic testing results for dehydroisomerization of n-butane indicated that incorporation of manganese increased the selectivity toward isomerization products. The highest isobutene selectivity (34.86%) could be obtained over a Pd/MnAPO-11 catalyst. When a combined catalyst system containing Pd/SAPO-11 and MnAPSO-11 was used in a single bed of two layers, the isobutene selectivity could be greatly improved, as compared to the single catalyst alone.

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A new copper-(Schiff-base) complex, derived from (S)-2-amino-1,1-di(3,5-di-t-butylphenyl)propanol, 2-hydroxy-5-nitrobenzaldehyde and copper acetate monohydrate, was used as an efficient catalyst for the cyclopropanation of styrene with diazoacetates, affording ees of up to 98%. (C) 2000 Elsevier Science Ltd. All rights reserved.

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从辽宁省大连海域分离到 1株海洋放线菌 ,编号MB 98,其产生的次生代谢产物对皮肤致病真菌白色念珠菌、石膏样毛癣菌、红色毛癣菌有很好的抑制作用。MB 98在大部分特征培养基上气丝为白色或白略粉 ,基丝为炒米黄或浅芒果棕 ,在所有培养基上均无色素产生 ,电镜观察MB 98孢子丝呈稀疏螺旋型 ,孢子呈椭圆或长圆柱型 ,孢子表面光滑 ,MB 98可以利用大部分碳源。根据分类鉴定研究 ,将MB 98定名为白色链霉菌海洋变种。