Palladium(II) complexes with Pd2S2 rings. Synthesis and theoretical characterization of [Pd2(dppe)2(μ-S)2] and X-ray characterization of [Pd3(dppe)3(μ3-S)2]Cl2

The use of the dppe ligand and the fine tuning of the experimental conditions has allowed isolation of [Pd₂(dppe)₂)(μ-S)₂], whose structural characterization has been achieved by ab initio MP2 calculations, and of [Pd₃(dppe)₃(μ₃-S)₂]Cl₂, the X-ray structure of which is also reported.     

Structure of a catalytically active octanuclear cobalt complex [Co(II)4Co(III)4(μ4-O)4(μ-O2CPh)12(PhCOOH)4]

The structure of a catalytically active octanuclear mixed-valence cobalt complex [Co(II)₄Co(III)₄(μ₄-O)₄(μ-O₂CPh)₁₂(PhCOOH)₄] (Ph = phenyl, C₆H₅) has been determined using an X-ray diffraction analysis. The presence of 16 ligands containing phenyl rings in each complex gives rise to strong steric stresses and leads to a disordering of terminal groups. The compound crystallizes in the monoclinic crystal system, space group of symmetry P2₁/n, with the unit cell parameters a = 18.076(5) ?, b = 26.371(3) ?, c = 22.791(5) ? β = 92.48(1)°, V = 10853(4) ?³, Z = 4, and ρ = 1.516 g/cm³. The final values of the discrepancy factors are R1 = 0.0441 for 4005 symmetrically nonequivalent reflections with I ≥ 2σ(I), wR2 = 0.1131, and GooF = 0.943.     

A Ladder-like Coordination Polymer [Sr(H2O)4(CuL)2]·(CuL)·2.25H2O Constructed From Metallo-Ligand Na[CuL] and Sr(NO3)2: Crystal Structure and ESR Study

Ligand L (H₃L = Glycylglycine, N-[1-(2-hydroxy,5-bromophenyl)propylidene]) has been prepared which contain flexible dipeptide group and substituted phenol group. The ligand react with Cu(NO₃)₂ to give the metallo-ligand [CuL]⁻, in which L acting as quadridentate ONNO chelate, coordinate to Cu(II) ion. The metallo-ligand [CuL]⁻ is rigid and has multifunctional groups. Reaction of metallo-ligand with Sr(NO₃)₂ leads to the formation of the title complexes [Sr(H₂O)₄(CuL)₂]· (CuL)·2.25H₂O (1). This heteronuclear compound has been characterized by elemental analyses, spectroscopic analyses, and single crystal diffraction. Structural analyses reveal that the complex was crystallized in triclinic space group P-1 and has intricate 2D net-structure, which contain an infinite 1D [Sr(H₂O)₄(CuL)₂]⁺ ladder-like structure. In addition ESR (electron spin resonance) property and thermogravimetric analysis of 1 are discussed in detail.     

[Ni（IMI）6]（NO3）2的制备与晶体结构

咪唑(IMI)与硝酸镍反应,得到硝酸六咪唑合镍配合物,并培养出单晶。元素分析、红外光谱、X射线单晶衍射等分析表明,该晶体属于单斜晶系,空间群为P21/n,晶胞参数a=1.235 0(3)nm,b=1.235 0(3)nm,c=1.480 0(3)nm,β=90.579(2)°,V=1.955 0(7)nm3,Dc=1.491 g/cm3,Z=4,F(000)=900,R1=0.034 4,wR2=0.095 5。该化合物的分子式为[Ni(IMI)6](NO3)2,是由6个咪唑分子直接与二价镍离子配位,硝酸根离子结合形成的配合物。     

离子液体[BMIM]3[CB3GA]萃取溶菌酶的影响因素分析

以离子液体[BMIM]3[CB3GA]作为萃取剂在不同操作条件下进行溶菌酶萃取实验。结果表明,[BMIM]3[CB3GA]离子液体的浓度为4 mmol/L、萃取时间为30 min及溶液呈酸性时,对溶菌酶的萃取效果最佳,可达90%以上;多次回收离子液体进行重复萃取时,[BMIM]3[CB3GA]对溶菌酶的萃取率无明显下降,也可维持在90%以上。     

Crystal Structure and Magnetic Properties of a Novel Helical Coordination Polymer [Cu2(pda)2(phen)2(H2O)2]·6H2O

A novel coordination polymer of Cu^II with flexible ligands, namely, [Cu ₂ (pda) ₂ (phen) ₂ (H ₂ O) ₂ ]·6H ₂ O (1) (H₂pda = 1,3-phenylenediacetic acid, phen = 1,10-phenanthroline), was synthesized by hydrothermal reactions and characterized by single-crystal X-ray diffraction, thermogravimetric analyses, elemental analysis and IR spectroscopy. In complex 1, the Cu^II ions are linked by pda ligands to form 1D helical chains. The adjacent chains are related by the π–π stacking interactions and exhibit opposite chirality, which result in extended 2D heterochiral helical-layers. Furthermore, the 2D helical-layers are assembled into 3D supramolecular edifices through heterochiral helical hydrogen bonding. In addition, the thermal stability and magnetic properties of 1 are reported.     

In vitro bioactivity of glass–ceramics of the CaMgSi2O6–CaSiO3–Ca5(PO4)3F–Na2SiO3 system with TiO2 or ZnO additives

Glass–ceramic materials based on diopside [CaMgSi₂O₆]–wollastonite [CaSiO₃]–fluoroapatite [Ca₅(PO₄)₃F]–sodium silicate [Na₂SiO₃] system with TiO₂ or ZnO additives were successfully prepared and examined in vitro, by using a simulated body fluid (SBF) solution, to be suitable for restorative dental and bone implant materials. In vitro bioactivity of the glass–ceramics was examined by using scanning electron microscopy equipped with energy dispersive X-ray detectors (EDAX–SEM) and inductive coupled plasma emission spectroscopy (ICP).     

Hydrothermal Synthesis and Crystal Structures of Cd(II)-Based 1D Coordination Polymer and Mn(II) Coordination Complex with Mixed N- and O-donor Ligands: [Cd2(4-4′-bpy)2(pa)4]n·0.25(H2O) and [Mn(4-4′-bpy)2(pa)(H2O)3]ClO4·2(H2O)

Two new complexes, [Cd₂(4-4′-bpy)₂(pa)₄] _n ·0.25H₂O (1) (pa = phenylacetate), and [Mn(4-4′-bpy)₂(pa)(H₂O)₃]ClO₄·2H₂O, (2), have been obtained from hydrothermal reaction of Cd(NO₃)₂·4H₂O and Mn(ClO₄)₂·6H₂O with a mixture of the ligands, 2-phenylmalonic acid (2-phmalH₂) and 4-4′-bipyridine (4-4′-bpy). The pa is formed in situ by decarboxylation of phenylmalonic acid. These complexes have been characterized by elemental analysis, FT-IR spectroscopy, thermogravimetric analysis and single-crystal X-Ray diffraction. The Cd(II) center is seven-coordinate and linked via pa ligands to form a binuclear complex in the asymmetric unit of 1. A ladder-like 1D chain of binuclear units is formed by Cd(II)–N coordination bond through 4-4′-bpy ligands. Complex 2 consists of a mononuclear manganese center based on a distorted octahedral geometry and exhibits a supramolecular structure containing hydrogen bonds and extensive π···π and C–H···π interactions.     

四元混配配合物[Ln(x-MBA)2(NO3)(Phen)]2的合成及表征

在酸性介质,乙醇/水混合溶剂中合成得到了三个系列的四元混配配合物[Ln(x-MBA)2(NO3)(Phen)]2(Ln=La、Ce、Pr、Nd、Sm、Eu、Gd、Tb、Er;MBA=CH3C6H4COO-).用元素分析、IR、UV、DTA-TG和1HNMR等方法对配合物进行了表征,测量了三个Eu配合物的荧光光谱和三个Gd配合物的ESR谱.     

Crystal structure and enhanced microwave dielectric properties of the Ce2[Zr1−x(Al1/2Ta1/2)x]3(MoO4)9 ceramics at microwave frequency

Dense microwave dielectric ceramics of Ce₂[Zr_1−x(Al_1/2Ta_1/2)_x]₃(MoO₄)₉(CZMAT) (x = 0.02–0.10) were prepared by the conventional solid-state route. The effects of (Al1/2Ta1/2)⁴⁺ on their microstructures, sintering behaviors, and microwave dielectric properties were systematically investigated. On the basis of the X-ray diffraction (XRD) results, all the samples were matched well with Pr₂Zr₃(MoO₄)₉ structures, which belonged to the space group R3¯c. The lattice parameters were obtained using the Rietveld refinement method. The correlations between the chemical bond parameters and microwave dielectric properties were calculated and analyzed by using the Phillips—Van Vechten—Levine (P—V—L) theory. Excellent dielectric properties of Ce₂[Zr_0.94(Al_1/2Ta_1/2)_0.06]₃(MoO₄)₉ with a relative permittivity (ε_r) of 10.46, quality factor (Q × f) of 83,796 GHz, and temperature coefficient of resonant frequency (τ_f) of −11.50 ppm/℃ were achieved at 850 ℃.     

Temperature-independent and enhanced dielectric properties for two-layer structure capacitors with 0.8Pb(Fe2/3W1/3)O3–0.2PbTiO3–MnO and 0.7Pb(Fe2/3W1/3)O3–0.3PbTiO3–MnO ceramics

This study fabricates capacitors with two-layer structure and different compositions, 0.8Pb(Fe_2/3W_1/3)O₃–0.2PbTiO₃–MnO and 0.7Pb(Fe_2/3W_1/3)O₃–0.3PbTiO₃–MnO, by using the conventional solid state oxide reaction method. By using the temperature compensation effect and adjusting the thickness ratio of the two layers with different compositions, the temperature–dielectric peak is enhanced and smoothed. The dielectric loss, space charge polarization and dc conduction are suppressed at the highest temperature region. Furthermore, the Maxwell–Wagner model is used to fit and explain the dielectric behaviors. This study also provides suggestions and discussion related to the effect of the interfacial region based on the experimental data and fitting results.     

Single-phase silicocarnotite synthesis in the subsystem Ca3(PO4)2–Ca2SiO4

In the last years, the addition of silicon to hydroxyapatite and tricalcium-phosphate materials is being widely studied, due to the well-known influence of silicon on bone formation. Silicocarnotite (Ca₅(PO₄)₂SiO₄) presents a structure type carnotite, very close to hydroxyapatite, with a wide range of Ca²⁺, SiO₄⁴⁻ and PO₄³⁻ solid solutions. These characteristics make silicocarnotite attractive as potential biomaterial.     

Cu2(NO3)(OH)3催化过硫酸盐降解苯酚

基于过硫酸盐的高级氧化工艺在高浓度含酚废水处理中引起了越来越多的关注。我们研究了Cu₂（NO₃）（OH）₃和过硫酸盐对于废水中苯酚的降解效果和机理。结果表明,Cu₂（NO₃）（OH）₃-过硫酸盐体系在较广泛的pH条件下（pH值为5.0~10.0）对苯酚的降解效率均较高。溶液中的总有机碳（TOC）分析表明,在pH值为8.0,1 g·L^-1过硫酸盐和1 g·L^-1 Cu₂（NO₃）（OH）₃条件下,该体系可在4 h内将初始浓度为100 mg·L^-1的苯酚完全矿化而没有产生二次污染。猝灭剂实验和电子顺磁共振（EPR）分析进一步证实Cu₂（NO₃）（OH）₃-过硫酸盐体系中的主要氧化物种是O₂^·-、SO₄^·-和¹O₂。     

On the local structure of Cd3+ centers in (BaGeO3)1 ? x ? y (Al2O3) x (0.45CaF2 · 0.55MgF2) y glasses

A correlation between the ¹⁵⁵Gd M?ssbauer spectra of the GdAlO₃ and Gd₃Al₅O₁₂ compounds and Gd³⁺-doped glasses in the (BaGeO₃)_{1 − x − y} (Al₂O₃) _x (0.45CaF₂ · 0.55MgF₂) _y system is revealed. The conclusion is drawn that, in the structure of the glasses under investigation, trivalent gadolinium atoms form structural units characteristic of mixed gadolinium and aluminum oxides. Original Russian Text ? S.A. Nemov, A.V. Marchenko, P.P. Seregin, 2008, published in Fizika i Khimiya Stekla.     

NaFexCry(SO4)2(OH)6的合成及电化学性能研究

随着国内外能源的过度消耗和环境污染，寻求高效、清洁、可持续的能源已成为当前的首要任务。关于易合成的黄钠铁矾在析氧反应(OER)方面的研究较少。因此，通过水热法合成了4种不同铁铬物质的量比的铬掺杂黄钠铁矾[Na Fe_x Cr_y(SO₄)₂(OH)₆]催化材料。利用SEM、XRD、Raman和电化学方法对其结构和性能进行表征。结果表明，Cr³⁺成功地掺入到黄钠铁矾晶格中，随着Cr³⁺掺杂量的增加，黄钠铁矾颗粒尺寸逐渐减小；在1 mol/L KOH的电解液中，n(Fe³⁺)/n(Cr³⁺)为1∶1的样品的OER催化性能最佳；当电流密度为10 m A/cm²时，其过电位为370 m V，塔菲尔斜率为92.99 mV/dec，电化学双层电容(C_dl)为10.94 mF/cm²。     

Sr0.5Zr2(PO4)3陶瓷的力学性能研究

用共沉淀法和低分子有机溶剂分散获得SZP粉体,经干压成型和烧结得到SZP陶瓷.研究了其力学性能与烧结温度烧结时间和添加剂用量的关系.最佳工艺条件为添加MgO6wt%,1300℃或ZnO3wt%,1200℃均烧结1.5小时,SZP陶瓷的抗压强度分别可达244.0MPa和226.2MPa.     

60%(CH3)2Si(OEt)2/40%Si(OEt)4有机-无机 复合醇盐水解聚合过程的研究

研究了有机-无机复合醇盐60%二甲基二乙氧基硅烷(DDS)/40%正硅酸乙酯(TEOS)的水解聚合过程. 通过测定不同水解时间后形成产物的结构及含量变化，分析了这种有机-无机复合材料水解聚合过程中有机与无机组分的相互作用机制及各种产物的形成规律. 指出DDS的添加抑制TEOS的自聚合，使得体系中形成了大量的TEOS和DDS的共聚合分子，有机与无机组分通过化学键合连接起来而成为一种凝胶网络组成体. 同时还检测到许多DDS的自聚合环状分子［（CH     

利用离子液体[BMIM]2[CR]萃取牛血清蛋白的研究

利用离子交换过程将亲和性染料刚果红合成为[BMIM]2[CR],并进行牛血清蛋白萃取实验。研究结果表明,[BMIM]2[CR]离子液体的浓度为10 mmol/L,萃取时间为30 min以及溶液呈酸性时,对牛血清蛋白的萃取效果最佳,可达90%以上。该研究可为[BMIM]2[CR]实际蛋白质萃取应用中提供一定的可行性条件。     

Bi(Zn1/2Ti1/2)O3 modified BiFeO3–BaTiO3 lead-free piezoelectric ceramics with high temperature stability

Lead-free high-temperature ceramics with compositions of 0.71BiFe_1−x(Zn_1/2Ti_1/2)_xO₃–0.29BaTiO₃ (BFZTx–BT, x=0–0.05 mol fraction) were fabricated by a conventional solid state reaction method. The effect of Bi(Zn_1/2Ti_1/2)O₃ (BZT) addition on the microstructure, electrical properties, relaxor behavior, and temperature stability has been studied. XRD patterns revealed that all compositions formed a single perovskite phase of pseudo-cubic crystal structure. The grain size was slightly affected by BZT addition. The diffuse phase transition and strong frequency dispersion of dielectric permittivity are observed for BZT modified ceramics. The addition of BZT into BFZTx–BT was also found to affect the piezoelectric properties and temperature stability of the ceramics with maximum values observed for x=0.5% and 1% BFZTx–BT compositions, respectively. The optimum piezoelectric properties with d₃₃=163 pC/N, together with high-temperature stability with a depolarization temperature T_d∼380 °C, reveal the BFZTx–BT ceramics to be promising high-temperature Pb-free piezoelectric materials.     

Piezoelectric and dielectric properties of (Bi0.5Na0.5)0.94Ba0.06TiO3–Ba(Zr0.04Ti0.96)O3 lead-free piezoelectric ceramics

Lead-free piezoelectric ceramics of (1 − x)(Bi_0.5Na_0.5)_0.94Ba_0.06TiO₃–xBa(Zr_0.04Ti_0.96)O₃ (abbreviated as BNBT–BZT100x, wherein x from 0 to 10 mol%) were fabricated. We have studied effects of amount of BZT content on the electrical properties and microstructures. X-ray diffraction analysis indicates that a solid solution is formed when BZT diffuses into the BNBT lattice, and further the crystal structure of sintered hybrid changes from rhombohedral to tetragonal symmetry along with increasing BZT content. Piezoelectric property measurements reveal that the BNBT–BZT4 ceramics has the highest piezoelectric performance, for example, the piezoelectric constant d₃₃ reaches to 167 pC/N and planar electromechanical coupling factor k_p is up to 0.27. In addition, the effect of Bi₂O₃ on the electrical properties and microstructure of the BNBT–BZT4 ceramics have also been studied, and found that the doping of Bi enhances the piezoelectric properties of ceramics.