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91.
合成了二十员大环双氮杂冠醚:2,3,l6,l7—二苯—l,8,ll,18—四氧—5,14—二氮杂环二十烷及其7个与稀土硝酸盐(RE^3 =La^3 ,Sm^3 ,Eu^3 ,Gd^3 ,Tb^3 ,Dy^3 。Yb^3 )所形成的1:2(M:L)型固体配合物,并经过红外光谱、元素分析、摩尔电导及热分析等方法对配合物进行了表征.结果表明,配位是通过配体中的C—O-C进行的,而Ar—O-C未参与配位,同时含2分子配位水.对Sm(Ⅲ),Eu(Ⅲ),Tb(Ⅲ),Dy(Ⅲ)的配合物进行了荧光光谱测定,所有配合物均有较强的荧光强度,其中Tb(Ⅲ)的配合物荧光强度最高,表明该新双氮杂冠醚配体三重态的能量与Tb(Ⅲ)的振动能级最为匹配.  相似文献   
92.
在pH1.4~2.4的NaAc HCl酸性缓冲介质中,药物雷洛昔芬与依文思蓝作用,形成离子缔合物,在280nm处产生强吸收。在此波长处吸光度A与雷洛昔芬浓度在0~2.3×10-5mol·L-1范围内,遵守比耳定律。建立了测定雷洛昔芬的分光光度法,测得表观摩尔吸光系数ε280达1.84×104L·mol-1·cm-1。该方法操作简便快捷,灵敏度较高,体系稳定。用于合成样中雷洛昔芬的测定,结果满意。  相似文献   
93.
以二(2-苯并咪唑亚甲基)胺(N3)为配体,合成了一种新型Cu(II)双核配合物作为超氧化物歧化酶(SOD)的模型化合物.采用元素分析、UV和IR光谱进行了表征,应用X射线衍射方法测定了晶体结构,并利用G98W程序在HF/LANL2DZ基组水平上对该双核配合物进行了量子化学计算.晶体结构分析表明,Cu(II)双核配合物的化学式量分子(C42H40N12O17Cl4Cu2)是以4,4′-联吡啶为桥的Cu(II)双核配合物单元,Cu(II)与配位原子形成变形八面体构型,轴向配位氧原子来源于高氯酸根.量化计算所得原子轨道贡献和原子净电荷布居分析结果与晶体结构中的配位情况相符.  相似文献   
94.
The aggregation behavior of various acid extractants in the solvent extraction systems of metal ions is re-examined and explained according to knowledge obtained in recent work. The conclusions are as follows. (1) Complexes formed by the extractants and metal ions can form reversed micelles in organic diluents, depending on the microstructures of the complexes. The dimers of the acid extractant cannot percolate to the metal-extractant aggregates, and the acid-salt complexes are always formed in the aggregates. The reversed micelles or the W/O microemulsions formed by different species cannot be associated with each other to form a unified aggregate. (2) In solvent extraction systems, hydration of the extractants and metal ions can be considered as the driving force of forming reversed micelles. (3) Information of the first approach to the insight of the bicontinuous microemulsion of NaDEHP shows that various components in the aqueous phase behave confined and very similar to the typical AOT/n-heptane W/O microemulsions. (4) In the extraction of lanthanide ions by the W/O microemulsion of sodium naphthenate, the saponification is a process of forming reversed micelle or W/O microemulsion, while the extraction step is a process of destroying reversed micelles or W/O microemulsion droplets.  相似文献   
95.
Pb isotopic geochemical study on the crustal structure of Tongbaishan   总被引:4,自引:0,他引:4  
Pb isotopic composition of the Tongbai complex, distributed in the Tongbaishan to the west of the Dabieshan, ranges between the Dabie core complex and the Dabie ultral-high pressure (UHP) metamorphic complex, the latter having more radiogenic Pb isotopic composition than the former. Granites from the Jigongshan pluton, which intruded mainly into the Tongbai complex, are distinct from the Tongbai complex but similar to the Dabie core complex in Pb isotopic composition, showing that the magma of the Jigongshan granites was derived from the partial melting of the Dabie core complex. According to Pb isotopic compositional variation model in the vertical crustal section and magma source from the Jigongshan pluton, it is suggested that the Tongbai complex was an upper rock serial of the Dabie core complex, which is beneath the Dabie UHP metamorphic complex in the crustal structure of the Tongbai-Dabie orogenic belt. The Tongbai complex was not well preserved in the Dabie area due to the high exhumed crustal section. However, the crustal section in the Tongbai area was exhumed less than that in the Dabie area, and the deep crust in the Tongbai area still contains the basement composition similar to the Dabie core complex. Therefore, the crustal basements from the Dabie to Tongbai areas are united. The present distribution of the basement blocks in different locations of the Tongbai-Dabie orogenic belt reflects different exposure of the crustal section.  相似文献   
96.
For simulating multi-scale complex flow fields it should be noted that all the physical quantities we are interested in must be simulated well. With limitation of the computer resources it is preferred to use high order accurate difference schemes. Because of their high accuracy and small stencil of grid points computational fluid dynamics (CFD) workers pay more attention to compact schemes recently. For simulating the complex flow fields the treatment of boundary conditions at the far field boundary points and near far field boundary points is very important. According to authors' experience and published results some aspects of boundary condition treatment for far field boundary are presented, and the emphasis is on treatment of boundary conditions for the upwind compact schemes. The consistent treatment of boundary conditions at the near boundary points is also discussed. At the end of the paper are given some numerical examples. The computed results with presented method are satisfactory.  相似文献   
97.
采用配体取代法合成出C60Ni(PPh3)2,利用元素分析、红外光谱、光电子能谱对产物进行表征,研究了产物的热稳定性和氯化还原性能。  相似文献   
98.
Gao  Shengli  Chen  Sanping  Yang  Xuwu  Shi  Qizhen 《科学通报(英文版)》2003,48(4):319-322
Seven novel solid complexes of the first-row transitional metal with L-α-histidine were synthesized, and their compositions were determined. The constant-volume combustion energies of the complexes were measured by a precision rotation bomb calorimeter. The standard molar enthalpies of combustion and the standard molar enthalpies of formation were calculated. The results indicated that the plots of the standard enthalpies of formation against the atomic number of the metal show a regularity of zigzag.  相似文献   
99.
以三(苯并咪唑-2-亚甲基胺)(NTB)为配体合成了ZnNTB·(NO3)2·DIPY·DMF(DIPY:4,4'-联吡啶)的单核锌配合物,用X-射线衍射法对其晶体结构进行了测定.晶体学参数:C37H36N12O7Zn,Mr=826.16,triclinic,a=0.9856(3)nm,b=1.2655(4)nm,c=1.5965(5)nm,α=81.714(5)o,β=76.601(5)o,γ=81.504(5)o,V=1.9032(10)nm3,Dc=1.442g/cm3,Z=2,F(000)=856,μ=0.712mm-1,空间群为P-1.采用经典的邻苯三酚自氧化法,对配合物进行了活性测试,其pI50值为4.21,说明该配合物具有拟SOD活性.利用G98量子化学程序包,在B3LYP/LanLDZ基组水平上对配合物C37H36N12O7Zn进行量子化学计算,对其分子轨道能量、电荷分布和前线轨道的贡献分析可知,所合成的配合物能与超氧阴离子自由基反应,与活性测试结果相符.  相似文献   
100.
从精神分析观点来看,卡夫卡与俄底浦斯情结之间有着显然的历史联系和必然的因果关系。俄底浦斯情结在卡夫卡身上实现了多层次的演绎和裂变。卡夫卡以他的现代主义创作和个人生活本身,对这种情结予以表现、深化和思考。  相似文献   
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