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1.
通过荧光光谱法研究了5种轴向核苷(胞苷、氮杂胞苷、甲基胞苷、尿苷和甲基尿苷)衍生物修饰硅酞菁与牛血清白蛋白(BSA)的相互作用,结果表明,它们与BSA存在较强的相互作用,结合常数在(4.90~83.18)×105 mol-1·L之间。因此,进一步制备了二[5’-(2’,3’-O-异丙基)-胞苷氧基]硅酞菁(SiPc1)与BSA的非共价复合物(SiPc1-BSA),复合物中两者的摩尔比为1∶1。SiPc1-BSA与SiPc1在可见区的吸收光谱没有明显区别,两者的Q带最大吸收带均位于686nm附近,且吸收强度没有明显区别,这说明SiPc1结合到白蛋白后,其光谱性质没有受到明显改变。光动力抗癌活性测试表明,SiPc1-BSA具有较高的光动力抗癌活性,对人肝癌细胞HepG2的IC50值为3.0×10-7 mol·L-1,且SiPc1-BSA的光动力活性高于SiPc1(PBS药剂形式,IC50值为7.0×10-7 mol·L-1),这主要可归因于SiPc1-BSA具有更高癌细胞摄取率。  相似文献   
2.
以有序介孔SiO2(简称KIT-6)为载体,采用钛酸丁酯水解法将纳米TiO2与KIT-6复合,并通过沉积沉淀法将纳米Ag粒子负载于其上,首次制得Ag-TiO2/KIT-6复合光催化剂,并采用相同的方法制备了一系列相关的催化剂.以光催化降解甲基橙来评价其催化性能,光催化活性顺序为Ag-TiO2/KIT-6>Ag/TiO2>TiO2/KIT-6>TiO2>Ag/KIT-6.利用XRD、N2物理吸附、XPS、UV-Vis DRS和TEM对系列催化剂进行表征,结果表明Ag-TiO2之间形成的异质结和催化剂的大比表面积是Ag-TiO2/KIT-6具有最高光催化活性的重要原因.其中Ag-TiO2之间的异质结结构,有效抑制了光生电子和光生空穴在TiO2表面和体相内部的复合,提高了光催化活性;此外Ag-TiO2/KIT-6的大比表面积大大提高了催化剂的吸附能力,增加了催化剂与污染物的接触,达到快速光催化降解污染物的目的.  相似文献   
3.
The title compound, a novel Ag(Ⅰ) carboxyarylphosphonate [Ag(H2BCP)(4,4'- bipy)]·2H2O (H3BCP = p-H2O3PCH2C6H4COOH, 4,4'-bipy = 4,4'-bipyridine), was synthesized by a hydrothermal reaction and characterized by elemental analysis, IR spectra and single-crystal X-ray diffraction. It belongs to monoclinic system, space group P21/c with a = 5.7038(11), b = 22.397(4), c = 5.602(4) ?, β = 106.26(3)°, V = 1913.4(7) 3, Z = 4, C18H20N2O7PAg, Mr = 515.20, Dc = 1.788 g/cm3, μ = 1.182 mm-1, F(000) = 1040, the final R = 0.0404 and wR = 0.1216 for 4178 observed reflections with I 2σ(Ⅰ). In the structure, the Ag(Ⅰ) cations are bridged by 4,4'-bipy to give rise to 1D chains running along the b axis. These chains are linked further by the interactions of O (from BCP ligands) and Ag atoms to yield 2D layers. Hydrogen bonding interactions and weak π-π stacking interactions between 4,4'-bipy rings assemble such adjacent layers to generate a 3D supramolecular architecture.  相似文献   
4.
A novel zinc(H) metal phosphonate compound [Zn(phen)(m-OOCC6H4PO3H)] 1 (phen = phenanthroline) has been synthesized under hydrothermal conditions. Single-crystal X-ray structure analysis reveals that compound 1 belongs to the triclinic system, space group P1 with a = 9.3356(19), b = 10.203(2),c = 10.743(2)A,α = 76.3030(70), β= 69.2317(51), y = 84.3833(74)°,V = 929.4(3) ,A3, Z = 2, C2OH15N2O5PZn, Mr = 459.68, Dc = 1.643 g/cm^3,μ= 1.444, mm^-1, F(000) = 468, the final R = 0.0330 and wR = 0.0848. In the structure, the central ion Zn(H) is five-coordinated, linking three O atoms with one from carboxyl and the other two from phosphonyl group. The remained two coordinate sites were occupied by two N atoms from one phen molecule to form the asymmetric unit. Then every two adjacent asymmetric units are bridged by the O atoms from phosphonate group and carboxyl to give rise to a 1D chain along the b axis. These chains are constructed by weak π-π stacking interactions and C-H…π interactions to generate a 3D supramolecular framework.  相似文献   
5.
本文对所合成的具有 [(PO4 ) 2 Mo5O1 5]簇骼的 3种新颖的有机 磷钼酸盐簇合物(NH3CH2 CH2 NH3) 2 5[(PO4 ) (HPO4 )Mo5O1 5]·7 5H2 O (Ⅰ ) ,(H3NCH2 CH2 NH3) 3·[(PO4 ) 2 Mo5O1 5]·3H2 O (Ⅱ )和(H3NCH2 CH2 NH3) 2 ·[Cu(en) ][(PO4 ) 2 Mo5O1 5]·5H2 O (Ⅲ )用FTIR ,NIR Raman ,紫外 可见漫反射光谱 (UV VisDRS)和荧光光谱等研究手段 ,对其进行光谱研究 ,探讨其结构和性能的关系。在这些化合物中 ,化合物Ⅰ和Ⅱ具有孤立的 [(PO4 ) 2 Mo5O1 5]簇骼基元 ,而化合物Ⅲ的 [(PO4 ) 2 Mo5O1 5]簇骼基元是由 [Cuen]基团桥联成链 ;磷钼酸盐的特征振动频率和这些化合物的结构相关 ;UV VisDRS显示 ,在 2 0 0和 2 6 0nm左右有两个杂多化合物的特征吸收谱带 ;化合物的稳态荧光光谱中 ,观察到以 2 4 0nm激发 ,在大约 4 0 0nm附近出现的由金属氧簇Oμ→Mo跃迁激发所引起的较强的发射峰 ,在化合物 (Ⅲ )中 ,还观察到通过 [Cuen]的荷移跃迁的以 5 70nm激发所产生的 6 0 4nm的发射峰。  相似文献   
6.
在(NH4)3VS4/CuI/Py反应体系中合成了新化合物 [VS4Cu6(Py)8I3]并测定其晶体结构。该化合物(C40H40N8Cu6I3S4V)属正交晶系, 空间群为Fdd2, 晶胞参数为: a = 29.924(6), b = 13.475(3), c = 25.853(5) , V = 10425(4) ?, Dc = 2.006 g/cm3, Mr = 1573.92, Z = 8, (MoK) = 4.546 mm-1, F(000) = 6048。结构由直接法解出, 用全矩阵最小二乘法修正, 最终偏离因子R = 0.023, wR = 0.069。簇合物分子是由6个带端基配体的Cu沿着四面体单元VS4的6条SS边配位而成, 6个Cu排列成了1个八面体, V基本位于八面体的中心, 整个分子具有C2对称性。  相似文献   
7.
合成了(La0.8M0.2)MnO3(M=Ca2+,Sr2+,Ba2+)和(La0.8Sr0.2)(Mn1-xFex)O3(x=0.1、0.2、0.3、0.4、0.5)两类氧化物,经XRD确认为钙铁矿型氧化物,应用FT-IR对其进行研究,对主要的红外特征振动υ(Mn-O)和δ(O-Mn-O)进行分析表征。这类化合物的υ(Mn-O)和δ(O-Mn-O)的FT-IR特征吸收峰十分相似,但在~608cm-1处出现较大差别,以Sr2+、Ca2+和Ba2+部分A位取代La3+的钙铁矿型氧化物和B位Fe取代Mn时,由于离子的溶解能不同,对晶格的有序排列的影响程度不一,导致了Mn-O键的键力场不同,引起了吸收峰向低波数移动。这种结构上的差异,导致对汽车尾气中的有害成份碳氢化合物(HC)和一氧化碳(CO)的催化氧化能力降低。借此可以用于研究结构与催化性能的关系。  相似文献   
8.
1 INTRODUCTION Transition metal oxide clusters and their deriva- tives offer an unmatched variety of structural motifs and wide ranging applications in several areas, such as analytical chemistry, materials science and cataly- sis, nanotechnology, chemical sensing, environmental decontamination, biochemical and geochemical pro- cesses, and medicine[1~3]. Polyoxovanadates or vana- dium oxide clusters constitute an important subclass of polyoxometalates and have been studied exten- sively.…  相似文献   
9.
[Zn2(PCP)(phen)(H2O)F]n 1 and {[Zn3(MCP)2(phen)2(H2O)]·2.5H2O}n 2(PCP = p-O2C(C6H4)PO33-,MCP = m-O2C(C6H4)PO33- and phen = phenanthroline) were obtained by hydrothermal synthesis and characterized by X-ray single-crystal diffraction.Compound 1 crystallizes in the monoclinic P21/c space group with a = 7.908(2),b = 20.254(3),c = 13.477(2) ,β = 107.76(3)°,V = 2055.7(8) 3,Z = 4,C20H16FN2O6PZn2,Mr = 561.10,Dc = 1.813 g/cm3,μ = 2.463 mm-1,F(000) = 1128,the final R = 0.0340 and wR = 0.0794.Compound 2 crystallizes in the monoclinic P21/n space group with a = 15.629(3),b = 18.141(4),c = 17.723(7) ,β = 121.89(2)°,V = 4267(2) 3,Z = 4,C40H31N4O13.5P2Zn3,Mr = 1041.70,Dc = 1.620 g/cm3,μ = 1.818 mm-1,F(000) = 2108,the final R = 0.0669 and wR = 0.1775.In compound 1,the tetranuclear Zn4 units are linked together by μ4-PCP3- to build 2D(4,4) layers,which are further interconnected through the μ2-bridging fluorion into a 3D framework with 1D phen ligands-filled channels.As for the 3D supramolecular framework of 2,the novel hexanuclear Zn6 units with "chair" conformation are extended by the moieties of μ4-MCP3- ligand to a 2D(4,4) layer on the bc plane,which is viewed as the 2-folded layers in 1.In both compounds,the structures are stabilized by hydrogen bonding interactions and π-π stacking interactions between the phen rings.Additionally,FT-IR spectroscopy and the fluorescent properties are discussed.  相似文献   
10.
The novel coordination polymer [Pr(BYBA)3(H2O)2]·[Pr(BYBA)3(H2O)] (BYBAH=2-benzoylbenzoic acid) was yielded by hydrothermal synthesis,determined by single-crystal X-ray diffraction,and characterized by FT-IR and UV-Vis spectra. The crystal crystallizes in the triclinic system,space group P1 with a=9.112(3),b=14.644(5),c=27.076(11),α=84.223(3),β= 87.816(4),γ=88.902(4)o,V=3592(2)3,C84H60O21Pr2,Mr=1687.14,Z=2,F(000)=1700,Dc= 1.560 g/cm3,μ=1.419 mm-1,the final R=0.0485 and wR=0.1258 for 13035 observed reflections with I > 2σ(I). The compound contains two different building units,[Pr2(BYBA)6(H2O)4] and [Pr2(BYBA)6(H2O)2]. It is noticeable that [Pr2(BYBA)6(H2O)4] is an isolated binuclear building block,in which the Pr3+ ion centers are both located in an eight-coordinated environment. However,in [Pr2(BYBA)6(H2O)2] the Pr3+ ion centers are located in a nine-coordinated environment and connected by BYBA ligands to form 1D chains.  相似文献   
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