Crystal structure of salts of the trans-[Rh(NH3)2(NO2)4]− anion with K+, Cs+, Ag+, and (CH3)4N+ cations

Complex rhodium(III) salts with the composition trans-M[Rh(NH₃)₂(NO₂)₄], where M = K⁺, Cs⁺, Ag⁺, and N(CH₃) ₄ ⁺ , are prepared and characterized. The molecular and crystal structures are determined by X-ray crystallography.     

Étude structurale comparée des chromates: M(I)M(III)(CrO4)2; M(I) = Li+, Na+, K+, Rb+, Cs+, NH4+, Ag+ et Tl+; M(III) = Al3+, Fe3+, Cr3+, Tl3+ et Bi3+

Among compounds of formula type M(I)M(III)(CrO₄)₂, the structures of trivalent bismuth compounds are always different from the others, because the surrounding of bismuth is never well-defined. Besides, nearly all these compounds have two-dimensional structures with the exception of Tl(I)Tl(III)(CrO₄)₂ which is three-dimensional. This structural type can exist only when the ionic radius of the monovalent cation has a value near that of O²⁻ ion (1.40 Å), as for Rb⁺, NH₄⁺ and Tl⁺.     

Complexation of 3-hydroxy-2,2′-iminodisuccinic acid (HIDS) with Mg2+, Ca2+, Mn2+, Fe3+, Fe2+, Co2+, Ni2+, Cu2+, and Zn2+ ions in aqueous solution

In a search for environmental-friendly metal chelating ligands for industrial applications, the protonation and complex formation equilibria of 3-hydroxy-2,2′-iminodisuccinic acid with Mg²⁺, Ca²⁺, Mn²⁺, Fe³⁺, Fe²⁺, Co²⁺, Ni²⁺, Cu²⁺, and Zn²⁺ ions in aqueous 0.1 mol L^?1 NaCl solution were studied at 25°C by potentiometric titration. The model for complexation and the stability constants of the different complexes were determined for each metal ion using the computer program SUPERQUAD. In all cases, complex formation was dominated by stable ML ^{n ?4} complexes.     

稀土离子(La3+, Gd3+, Yb3+, Ce3+)对线粒体的氧化损伤

主要考察了稀土离子对线粒体氧化损伤(膜脂质过氧化、膜蛋白氧化、线粒体DNA氧化)的作用。结果表明,稀土离子(La3 ,Gd3 ,Yb3 ,Ce3 )浓度大于2×10-5mol.L-1时,对线粒体膜脂质过氧化、膜蛋白氧化均有明显的促进作用;在对Fe2 诱导的线粒体氧化过程中,La3 ,Gd3 和Yb3 能明显地增强Fe2 的氧化作用,而Ce3 对Fe2 的作用表现出明显的拮抗作用,此外Ce3 对Fe2 诱导的线粒体DNA氧化损伤表现出明显的拮抗作用,显示了Ce3 的特殊性。     

稀土离子(La3+,Ce3+,Tb3+,Y3+)对炎症及血小板聚集的影响

研究稀土离子(La3 ,Ce3 ,Tb3 ,Y3 )对炎症、血小板聚集及蛋白磷酸化的影响.采用二甲苯使小鼠耳部致炎,腹腔注射稀土离子,观察炎症的变化;利用血小板聚集仪观察稀土离子对血小板聚集的影响;用放射标记法测量稀土对血小板蛋白磷酸化程度的影响.结果表明,稀土离子在2.5×10-4mol·L-1·kg-1的注射剂量下,能显著加强炎症反应;1×10-3mol·L-1的轻稀土(La3 ,Ce3 )对由ADP诱导的血小板聚集有明显的抑制作用,而重稀土(Tb3 ,Y3 )有明显的促进作用;浓度在1×10-6～1×10-4mol·L-1时,轻、重稀土均可促进血小板蛋白磷酸化.稀土离子对炎症、血小板聚集及蛋白磷酸化的影响与稀土的种类和剂量有关.     

Study of the state of uranoarsenates MII(AsUO6)2·nH2O(MII = Mn2+, Co2+, Ni2+, Cu2+, Zn2+, Cd2+, Pb2+) in aqueous solutions

State of uranoarsenates M^II(AsUO₆)₂·nH₂O (M^II = Mn, Co, Ni, Cu, Zn, Cd, Pb) in aqueous solutions in a wide range of acidity (pH 0?C14) was studied. Acid-base boundaries of existence of the compounds were estimated, products of conversion were identified, and solubility of M^II(AsUO₆)₂·nH₂O was determined. On the basis of the obtained data the solubility products and Gibbs functions of formation of uranoarsenates, and the solubility curves were calculated, phase diagrams of uranium(VI) and arsenic(V) in solutions and in equilibrium solid phases were constructed with the use of the equilibrium thermodynamics technique.     

Re-dispersion and film formation of GdVO4 : Ln3+ (Ln3+ = Dy3+, Eu3+, Sm3+, Tm3+) nanoparticles: particle size and luminescence studies

GdVO(4)?:?Ln(3+) (Ln(3+) = Dy(3+), Eu(3+), Sm(3+), Tm(3+)) nanoparticles are prepared by a simple chemical route at 140 °C. The crystallite size can be tuned by varying the pH of the reaction medium. Interestingly, the crystallite size is found to increase significantly when pH increases from 6 to 12. This is related to slower nucleation of the GdVO(4) formation with increase of VO(4)(3-) present in solution. The luminescence study shows an efficient energy transfer from vanadate absorption of GdVO(4) to Ln(3+) and thereby enhanced emissions are obtained. A possible reaction mechanism at different pH values is suggested in this study. As-prepared samples are well dispersed in ethanol, methanol and water, and can be incorporated into polymer films. Luminescence and its decay lifetime studies confirm the decrease in non-radiative transition probability with the increase of heat treatment temperature. Re-dispersed particles will be useful in potential applications of life science and the film will be useful in display devices.     

Complexation of iminodisuccinic acid (IDS) and 3-hydroxy-2,2′-iminodisuccinic acid (HIDS) with Cd2+, Hg2+, and Pb2+ in aqueous solution

In a search for environmentally friendly metal-chelating ligands for industrial applications, the protonation and complex formation equilibria of iminodisuccinic acid (IDS) and 3-hydroxy-2,2′-iminodisuccinic acid (HIDS) with Cd²⁺, Hg²⁺, and Pb²⁺ in aqueous 0.1?mol?L^?1 NaNO₃ solution were studied at 25°C by potentiometric titration. Models for complexation and stability constants of the different complexes were determined for each metal ion using the computer program SUPERQUAD. In all cases, complex formation was dominated by stable ML^2? complexes.     

Na~+,Li~+,Bi~(3+)掺杂CaWO_4∶Eu~(3+)荧光粉的制备及发光特性

采用微波辅助加热法合成了Na~+,Li~+,Bi~(3+)掺杂的CaWO_4∶Eu~(3+)荧光粉.利用X射线衍射仪和扫描电子显微镜对样品的微观结构进行了表征,利用荧光分光光度仪对样品的激发光谱、发射光谱和能级寿命进行了测试和分析.结果表明,掺杂浓度(摩尔分数)均为3.75%的Eu~(3+),Na~+,Li~+,Bi~(3+)掺杂的CaWO_4均保持了基质的四方晶相结构.Na~+,Li~+,Bi~(3+)单掺杂或共掺杂后的样品比CaWO_4∶Eu~(3+)样品颗粒度分别有不同程度的增加.在393 nm光激发下,掺杂Eu~(3+),Na~+及掺杂Eu~(3+),Li~+样品的发光强度比CaWO_4∶Eu~(3+)的发光强度分别提高了1.8倍和1.2倍,共掺杂Eu~(3+),Li~+,Na~+及Eu~(3+),Li~+,Bi~(3+)的样品发光均有所减弱.在254和393 nm光激发下,掺杂Li~+的CaWO_4∶Eu~(3+)样品的荧光寿命最短.同一样品在393 nm光激发下的荧光寿命短于254nm光激发下的荧光寿命.     

Complexing Power of Vitamin D3 Toward Various Metals. Potentiometric Studies of Vitamin D3 Complexes with Al3+, Cd2+, Gd3+, and Pb2+ Ions in Water–Ethanol Solution

This study reports the stability constants of complexes with vitamin D₃ and Al³⁺, Cd²⁺, Gd³⁺ and Pb²⁺ ions in a water–ethanol medium (30/70% v/v at 25.0°C). The logarithms of the overall stability constants are: ₁ = 12.4 ± 0.5, 7.6 ± 0.3, 9.33 ± 0.07, and 9.1 ± 0.5, respectively, whereas the logarithms of ₂ are 24.4 ± 0.5 (Al³⁺), 14.3 ± 0.3 (Cd²⁺), and 15.4 ± 0.5 (Pb²⁺). Gd³⁺ forms only the 1:1 complex. These values are compared to those reported previously and correlations are established between the stability constants and physical properties, such as the ionization energy.     

Synthesis and Spectroscopic Characterization of Organothiophosphoryl Polyoxotungstates α- [C6H11P (S) ]2Xn+W11O39(8-n)- (Xn+ = P5+, Si4+, Ge4+, Ga3+)

Organothiophosphoryl polyoxotungstate derivatives α-C6H11P(S)]2Xn W11O39(8-n)- (X=P, Si, Ge, Ga)were obtained by the reactions of the monovacant α-[Xn W11O39](12-n)- (X=P, Si, Ge, Ga) anions with electrophilic C6H11P(S)Cl2 in acetonitrile. These new organic-inorganic hybrid anions were characterized by elemental analyses, IR, 31P and 183W NMR spectrometries. The six-line 183W NMR spectrum indicates that [C6H11P (S) ]2Xn W11O39(8-n)- (X= P, Si, Ge, Ga) anions possess true Cs symmetry in acetonitrile. According to the spectroscopic observation and the chemical analyses, it is known that each of the hybrid anions consists of an α-[XW11O3)] framework on which two equivalent C6H11P(S) groups are grafted through P-O-W bridges.     

Total Synthesis of 3 (R)-Panaxynol

Panaxynol1,asacommonconstituentofmanyplantparts',wasfirstdescribedbyTakahashietal.2in1964asaconstituentofPanaxyginseng.C.A.MeyershowedinhisBioassayshowedthatpanaxynolhadselectiveinvitrocytotoxicityagainstL-1210',MKI,B-16,andL-929cancercelllinescomparedtonormalcellcultures4.TheabsoluteconfigurationhadbeenestablishedbyLarsenetal.5tobe3R.Hereinwereportthefirsttotalstereoselectivesynthesisofpanaxynol(l).C'-CIafragmentofpanaxynol1wasobtainedaccordingtothefollowingsequencefReagentsandconditio…     

一缺位杂多阴离子XW11O(12-n)-39(X=P5+,Si4+,B3+,Ga3+)含硫有机膦衍生物的合成及结构表征

杂多化合物的衍生物由于具有潜在的多功能催化性能,长期以来一直受到人们的关注[1～3].将有机或有机金属基团引入杂多化合物中以修饰杂多阴离子的部分外部骨架结构,对研究杂多化合物的性质和应用及新型催化剂的开发具有重要意义[4,5].在杂多化合物表面引入适当的有机基团还可改善其溶解性能及其它物理性质,从而拓宽其应用范围.研究结果表明,这类化合物还具有很好的抗病毒和抗肿瘤活性[6,7].Klemperer等[8]合成的[(η5-C5H5)TiPW11O39]4-将多酸与金属有机化合物有机地融为一体,从而开辟了多酸金属有机化学的新领域.此后,相继合成了许多多酸型金属有机化合物[9],然而缺位杂多阴离子的有机膦衍生物的研究却鲜见报道[10].     

多孔磁体甲酸盐[M3(HCOO)6](M=Mn2+,Fe2+,Co2+,Ni2+,Fe2+/Zn2+)的研究

综述了近年来我们在多孔磁体甲酸盐系列[M3(HCOO)6](M=Mn2 ,Fe2 ,Co2 ,Ni2 ,Fe2 /Zn2 )获得的研究结果.这些多孔磁体可以在常温下用温和的溶液化学方法制备获得,它们的结构是以MM4四面体为节点的金刚石多孔骨架,呈现了很好的热稳定性、多孔性、广谱的客体包合性能和稳定性.由于客体的包合对多孔磁性骨架的结构参数产生影响以及客体和骨架之间的弱氢键相互作用,这些多孔磁体表现了丰富的和客体调控的磁性质.混合金属的多孔磁体[FexZn3-x(HCOO)6]表现了随着Zn2 的含量增加而发生的由三维磁有序到自旋玻璃、再到超顺磁体、最后到顺磁体的渐次转变.     

钙钛矿结构荧光材料MZrO3:Eu3+,A (M=Ca2+, Ba2+; A=Li+, Na+, K+)的制备及其发光性质

Calcium and barium zirconate powders based upon CaZrO₃:Eu³⁺,A and BaZrO₃:Eu³⁺,A (A=Li⁺, Na⁺, K⁺) were prepared by combustion synthesis method and heating to ~1000℃ to improve crystallinity.The structure and morphology of materials were examined by X-ray diffraction (XRD) and scanningelectron microscopy (SEM). XRD results showed that CaZrO₃:Eu³⁺,A and BaZrO₃:Eu³⁺,A (A=Li⁺, Na⁺, K⁺) perovskites possessed orthorhombic and cubic structures, respectively. The morphologies of all powderswere very similar consisting of small, coagulated, cubical particles with narrow size distributions andsmooth and regular surfaces. The characteristic luminescences of Eu³⁺ ions in CaZrO₃:Eu³⁺,A (A=Li⁺, Na⁺, K⁺) lattices were present with strong emissions at 614 and 625 nm for ⁵D₀→⁷F₂ transitions with other weakeremissions observed at 575, 592, 655, and 701 nm corresponding to ⁵D₀→⁷F_n transitions (where n=0, 1, 3, 4 respectively). In BaZrO₃:Eu³⁺ both the ⁵D₀→⁷F₁ and ⁵D₀→⁷F₂ transitions at 595 and 613 nm were strong.Photoluminescence intensities of CaZrO₃:Eu³⁺ samples were higher than those of BaZrO₃:Eu³⁺ lattices. Thisremarkable increase of photoluminescence intensity (corresponding to ⁵D₀→⁷F_n transitions) was observedin CaZrO₃:Eu³⁺ and BaZrO₃:Eu³⁺ if co-doped with Li⁺ ions. An additional broad band composed of manypeaks between 440 to 575 nm was observed in BaZrO₃:Eu³⁺,,A samples. The intensity of this band wasgreatest in Li⁺ co-doped samples and lowest for K⁺ doped samples.