937 resultados para 35Cl MRI
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利用能量为164-180MeV的35Cl束流,通过重离子核反应149Sm(35Cl,5n) 研究了179Au的高自旋态能级结构。实验进行了γ射线的激发函数、X-γ和γ-γ-t符合测量。基于实验测量结果,首次建立了179Au的1/2[660](πi13/2)转动带。结合已有的实验数据,着重讨论了奇-A Au核中1/2[660](πi13/2) 转动带的形变和带头激发能随中子数的变化。用能量为140MeV的29Si束流轰击159Tb金属靶,布居了183Au核的高自旋态。实验中要求至少有3个高纯锗和2个BGO探测器同时点火,在此符合条件下,记录高纯锗探测器探测到的γ射线的能量和相对时间、BGO探测到的γ射线的总能量和多重性。通过对实验数据的分析,扩展并更新了183Au的能级纲图。首次建立了183Au的πi13/2转动带的能量非优先带。分析并讨论了缺中子奇-A Au中πh9/2转动带的能量非优先带和πf7/2转动带间的相互作用
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本论文介绍了原子核高自旋态研究的一般概况及有关核模型,描述了在束γ谱实验的原理与技术、数据分析与处理方法,然后着重分析和讨论了双奇核190Tl和146Tb高自旋能级结构的特性。 利用能量为175和167MeV的35Cl束流,通过反应160Gd(35Cl,5n)研究了双奇形变核190Tl的高自旋能级结构。实验进行了γ射线的激发函数和各向异度、X-γ和γ-γ-t符合测量,建立了由πh9/2νi13/2扁椭球转动带和一个具有单粒子激发特征的级联组成的190Tl能级纲图。确定地指定了190Tl的转动带自旋值,首次发现了190Tl πh9/2νi13/2扁椭球转动带的低自旋旋称反转。基于双奇核Tl能级结构的相似性,重新指定了双奇核192-200Tl πh9/2νi13/2扁椭球转动带能级自旋值,澄清了二十多年来国际上一直没有解决的自旋值指定问题且在这些扁椭形变核中均出现了低自旋旋称反转。考虑了p-n剩余相互作用的2-准粒子—转子模型定性地解释πh9/2νi13/2扁椭球转动带出现的低自旋旋称反转现象。 利用118Sn(32S ,1p3n)反应研究了双奇球形核146Tb的高自旋态,建立了激发能达8.39 MeV的能级纲图,其中包括新发现的41条γ射线和新建立的27个能级,并指定了新发现能级的自旋值和部分能级的组态。146Tb81的低位激发态是二准粒子态,高位的激发态是四准粒子态,或二准粒子与偶偶核芯低位激发态的耦合,更高位的能级则是六准粒子态,甚至八准粒子态。利用经验壳模型对部分全顺排组态的激发能进行了理论计算
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本论文首先介绍了在束谱学实验技术研究原子核高自旋态的基础理论知识,然后描述了实验数据的处理方法。在此基础上,详细分析并讨论了188Tl核高自旋态能级结构的性质。利用能量为170 MeV 的35Cl束流,通过157Gd(35Cl,4n)熔合蒸发反应研了188Tl的高自旋态能级结构。基于实验结果,建立了188Tl基于质子h9/2
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本论文分为两部分,分别沿自旋和同位旋自由度开展研究工作。第一部分介绍原子核高自旋态研究的相关背景知识、基础理论等,描述在束γ谱学研究的实验技术和方法,分析和讨论形变核179Pt转动带能级结构的特性,并采用相关理论对其进行分析。通过融合蒸发反应149sm(35cl,P4n)布居奇A核179Pt的高自旋激发态。指认179Pt的组态为1/2-[521],5/2-[512〕和7/2+〔633〕的三条转动带。在hco=0.27 Mev附近,观测到1/2-〔521]带内顺排角动量突然增大,建议该现象是由一对113/2中子发生顺排造成的。另外观察到在7/2+〔633]带中出现较大的旋称劈裂。建议由于三轴形变加强了波函数中来自几=1/2轨道的组分,从而导致较大的旋称劈裂的出现。论文第二部分介绍重丰中子核衰变性质研究以及新核素合成、鉴别工作的相关背景知识、理论基础及实验技术。并对相关的研究工作分别进行阐述。通过快中子反应合成并鉴别了新核素19705和新的同核异能素186rnTa,利用γ(x)谱学方法首次建立了19705的部分衰变纲图。测得它们的半衰期分别为2.8士0.6 min和1.50.1 min,并与理论计算结果进行了比较;进行了原子核基态β延发裂变(pDF)的实验研究,经测量首次发现了230Ac的两个pDF事件,测得23OAc的pDF几率为(1.19±0.40)
Resumo:
利用能量为164-180MeV的35Cl束流,通过重离子核反应149Sm(35Cl,5n) 研究了179Au的高自旋态能级结构。实验进行了γ射线的激发函数、X-γ和γ-γ-t符合测量。基于实验测量结果,首次建立了179Au的1/2[660](πi13/2)转动带。结合已有的实验数据,着重讨论了奇-A Au核中1/2[660](πi13/2) 转动带的形变和带头激发能随中子数的变化。用能量为140MeV的29Si束流轰击159Tb金属靶,布居了183Au核的高自旋态。实验中要求至少有3个高纯锗和2个BGO探测器同时点火,在此符合条件下,记录高纯锗探测器探测到的γ射线的能量和相对时间、BGO探测到的γ射线的总能量和多重性。通过对实验数据的分析,扩展并更新了183Au的能级纲图。首次建立了183Au的πi13/2转动带的能量非优先带。分析并讨论了缺中子奇-A Au中πh9/2转动带的能量非优先带和πf7/2转动带间的相互作用
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本论文介绍了原子核高自旋态研究的一般概况及有关核模型,描述了在束γ谱实验的原理与技术、数据分析与处理方法,然后着重分析和讨论了双奇核190Tl和146Tb高自旋能级结构的特性。 利用能量为175和167MeV的35Cl束流,通过反应160Gd(35Cl,5n)研究了双奇形变核190Tl的高自旋能级结构。实验进行了γ射线的激发函数和各向异度、X-γ和γ-γ-t符合测量,建立了由πh9/2νi13/2扁椭球转动带和一个具有单粒子激发特征的级联组成的190Tl能级纲图。确定地指定了190Tl的转动带自旋值,首次发现了190Tl πh9/2νi13/2扁椭球转动带的低自旋旋称反转。基于双奇核Tl能级结构的相似性,重新指定了双奇核192-200Tl πh9/2νi13/2扁椭球转动带能级自旋值,澄清了二十多年来国际上一直没有解决的自旋值指定问题且在这些扁椭形变核中均出现了低自旋旋称反转。考虑了p-n剩余相互作用的2-准粒子—转子模型定性地解释πh9/2νi13/2扁椭球转动带出现的低自旋旋称反转现象。 利用118Sn(32S ,1p3n)反应研究了双奇球形核146Tb的高自旋态,建立了激发能达8.39 MeV的能级纲图,其中包括新发现的41条γ射线和新建立的27个能级,并指定了新发现能级的自旋值和部分能级的组态。146Tb81的低位激发态是二准粒子态,高位的激发态是四准粒子态,或二准粒子与偶偶核芯低位激发态的耦合,更高位的能级则是六准粒子态,甚至八准粒子态。利用经验壳模型对部分全顺排组态的激发能进行了理论计算
Resumo:
本论文首先介绍了在束谱学实验技术研究原子核高自旋态的基础理论知识,然后描述了实验数据的处理方法。在此基础上,详细分析并讨论了188Tl核高自旋态能级结构的性质。利用能量为170 MeV 的35Cl束流,通过157Gd(35Cl,4n)熔合蒸发反应研了188Tl的高自旋态能级结构。基于实验结果,建立了188Tl基于质子h9/2
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A green one-step approach has been developed for the synthesis of amino-functionalized magnetite nanoparticles. The synthesis was accomplished by simply mixing FeCl2 with arginine under ambient conditions. It was found that the Fe2+/arginine molar ratio, reaction duration and temperature greatly influence the size, morphology and composition of magnetic nanoparticles. The arginine-stabilized magnetic nanoparticles were characterized by transmission electron microscopy, x-ray diffraction, x-ray photoelectron spectroscopy, thermogravimetric analysis, and Fourier transform infrared spectroscopy techniques.
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Water solubility and surface functionalization of magnetic nanoparticles are crucial for bioapplication.[1]In this study,we presented a facile coprecipitation approach to synthesize lysine stabilized Fe3O4 nanoparticles.Lysine functionalized magnetite nanoparticles show an excellent colloidal stability of >20h.The as-synthesized magnetite nanoparticles have abundant amine groups on their surface which provide convenient sites for covalent linking of biological macromolecules.We believe that these amine-functionalized magnetic nanoparticles can be potentially used in fields such as magnetic bio-separation,immunoassay,MRI,and targeted drug delivery.
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以两种夹心型锰杂多配合物K10[Mn4(PW9O34)2]·22H2O和Na16[Mn4(H2O)2(P2W15O56)2]·53H2O作为研究对象,采用元素分析和红外光谱对其结构进行了表征,测试其在水中、牛血清白蛋白及运铁蛋白溶液中的弛豫效率,并进行了大鼠活体成像实验.结果表明,这两种锰杂多配合物的弛豫效率高于或接近于目前临床常用的造影剂Gd-DTPA,对肝脏和肾脏MRI信号具有良好的增强效果,是比较好的潜在磁共振成像造影剂候选化合物.
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Two mono-substituted manganese polyoxometalates, K6MnSiW11O39 (MnSiW11) and K8MnP2W17O61 (MnP2W17), have been evaluated by in vivo and in vitro experiments as the candidates of potential tissue-specific contrast agents for magnetic resonance imaging (MRI). T-1-relaxivities of 12.1 mM(-1) s(-1) for MnSiW11 and 4.7 mM(-1) s(-1) for MnP2W17 (400 MHz, 25 degrees C) were higher than or similar to that of the commercial MRI contrast agent (GdDTPA). Their relaxivities in BSA and hTf solutions were also reported. After administration of MnSiW11 and MnP2W17 to Wistar rats, MR imaging showed longer and remarkable enhancement in rat liver and favorable renal excretion capability. The signal intensity increased by 74.0 +/- 4.9% for the liver during the whole imaging period (90 min) and by 67.2 +/- 5.3% for kidney within 20-70 min after injection at 40 +/- 3 mu mol kg(-1) dose for MnSiW11. MnP2W17 induced 71.5 +/- 15.1%. enhancement for the liver in 10-45 min range and 73.1 +/- 3.2% enhancement for kidney within 5-40 min after injection at 39 +/- 3 mu mol kg(-1) dose. In vitro and in vivo study showed MnSiW11 and MnP2W17 being favorable candidates as the tissue-specific contrast agents for MRI.
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Herein we report the spectroscopic, electrochemical, TEM and DLS characterizations Of C-60 supramolecular inclusion complexes with alpha-, beta- and gamma-cyclodextrins prepared using anionic C-60. The results indicate that the cyclodextrin itself has little effect on the encapsulated C-60 or on the properties of the inclusion complex. Instead, the cyclodextrin has a significant influence on the aggregation behavior of individual complex in aqueous solution, which in turn affects the property of the supramolecular complex of cyclodextrin and C-60 greatly, As the cavity dimension of cyclodextrin becomes smaller as it changes from gamma-CD to beta-CD, and finally to alpha-CD, it is observed that more aggregation occurs for the corresponding inclusion complex in aqueous solution.
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Arabinogalactan-Gd-DTPA was synthesized by the reaction of diethylenetriaminepenta-acetic acid (DTPA) bisanhydride with polysaccharide in dry DMSO and characterized by FTIR, elemental analysis and ICP-AES. Its stability was investigated by competition with Ca2+, EDTA, DTPA. The t(1)-relaxivity is 8.06 mmol(-1) . L . s(-1) in D2O, 8.48 mmol(-1) . L . s(-1) in 0.725 mmol . L-1 BSA, respectively. t(1)-weighted MR imaging of rat kidney and liver showed a remarkable enhancement post injection of Arabinogalactan-Gd-DTPA. The results indicate that the arabinogalactan-Gd-DTPA is a potential contrast agent for MRI.
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合成了阿拉伯半乳聚糖修饰的 DTPA钆配合物 ,用红外光谱、元素分析、 ICP-AES等手段进行了表征 ,用竞争性方法研究了其在水溶液中的稳定性 ,测试了其在水中及 BSA溶液中的弛豫性能 ,并进行了体内成像实验 .结果表明 ,其弛豫效率是目前临床所用造影剂 Gd-DTPA的 1 .5~ 2 .0倍 ,对肝脏和肾脏 MRI信号具有良好的增强效果 ,是比较好的潜在磁共振成像造影剂
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Two rare earth heteropolymetalates K9GdW10O36 and K-11[Gd(PW11O39)(2)] have been synthesized and characterized by IR and elemental analysis. Their stability has been studied by TG - DTA. The TG - DTA analysis show that both complexes are of good thermal stability. Their relaxivity in D2O is 6.89 and 5.27 mmol(-1).s(-1) respectively. Interaction with BSA has also been investigated. The results indicate that the two rare earth heteropolymetalate may be potential contrast agent for MRI.