Synthesis and characterization of Sr(10−x)Cdx(PO4)6Y2 (Y = OH and F): A comparison of apatites containing two divalent cations

Cadmium substituted strontium hydroxy- and fluoro-apatites, Sr_(10−x)Cd_x(PO₄)₆Y₂ (Y = OH and F), have been prepared as single phases in the 0 ≤ x ≤ 4 interval for the former and 0 ≤ x ≤ 6 for the latter compound, respectively. The refinements of the X-ray full powder patterns allowed the structure determination of nine samples, and showed a preference of cadmium atoms for the M(1) site in fluoroapatite samples. IR investigation gave information about the nature of the metal oxygen interactions. The obtained results are used for a comparative discussion about the factors which drive the mutual substitution of Ca, Sr, Cd and Pb in apatites. The important role of electronegativity and polarisability, as well as of ionic radii, is evidenced.     

Nickel-boron nanolayer evolution on boron carbide particle surfaces during thermal treatment

This study is focused on reduction of Ni₂O₃ and B₂O₃ in the Ni-B nanolayer on B₄C particle surfaces and understanding of the nanolayer composition and morphology changes. Initially, the nanolayer contains Ni₂O₃, B₂O₃, and amorphous boron. After 400 °C thermal treatment in a H₂-Ar atmosphere, Ni₂O₃ is reduced to nickel; the nanolayer morphology is maintained and the coated particles demonstrate magnetism. As the thermal treatment temperature is increased to 550 °C, B₂O₃ is reduced to boron, which reacts with nickel and forms Ni₂B. Simultaneously, the nanolayer evolves into nanoparticles. Thermal treatment temperature increase to 700-900 °C only causes Ni₂B particle growth but does not fundamentally change the composition or phase.     

A new 3D supramolecular compound containing 1D chains and 1D water chains

The first crystal structure involving the discrete unsubstituted 1,2,4-triazolate anion is reported. In the title compound, [Na₂(H₂O)₈]_n(trz)_2n [trz = 1,2,4-triazolate] (1), each sodium(I) ion is coordinated by six water molecules with a slight distorted octahedron geometry. Each Na(I) are bridged by two μ₂-aqua ligands and arranged in an alternating fashion to construct a 1D zigzag {[Na₂(H₂O)₈]²⁺}_n chain. The 3D supermolecular framework is formed with 1D {[Na₂(H₂O)₈]²⁺}_n chain as the assembly units, by 1D water chain and 1,2,4-triazolate anion as the hydrogen bonding spacers.     

Synthesis, crystal structure and electrochemical properties of a novel tetranuclear silver(I) cluster based on 1,1′-bis[(2-hydroxybenzylidene)thiocarbonohydrazono-1-ethyl] ferrocene (FcL)

A novel tetranuclear silver(I) heterocyclic cluster, which is of nano-hole structure, based on 1,1′-bis[(2-hydroxybenzylidene)thiocarbonohydrazono-1-ethyl] ferrocene (FcL) has been prepared and structurally characterized by single-crystal X-ray diffractions. In addition, its electrochemical properties are also discussed. The results confirm that the receptor FcL is responsive to Ag⁺.     

Synthesis, characterization, crystal structure and theoretical calculations of an organotin(IV) complex with dithizone

The reaction of dimethyl tin dichloride with 1,5-diphenylthiocarbazone affords the complex [Sn(CH₃)₂(C₁₂H₁₁N₄S)Cl]. Its X-ray structure reveals a five-coordinated Sn atom in distorted trigonal bipyramidal geometry. The complex has been additionally characterized by IR and UV–Vis spectroscopy. Geometry optimization calculations support the experimental data.     

Two novel macrocyclic polyselenaferrocenophanes: Synthesis, crystal structures and electrochemical study

Two novel macrocyclic polyselenaferrocenophanes, 1,5,9-triselena[9]ferrocenophane (1) and 1,5,9,21,25,29-hexaselena[9.9]ferrocenophane (2), have been prepared by the reaction of 1,1’-bis(3-bromopropylseleno)ferrocene and Na₂Se. The new compounds have been characterized by a range of spectroscopic and analytical techniques, including ¹H, ¹³C NMR spectrometry and X-ray crystallography.     

A 3D Gd–Ag coordination polymer constructed from pyridine-3,5-dicarboxylic acid: Synthesis, crystal structure and magnetic properties

A novel heterometallic coordination polymer, [AgGd(PDC)₂]·2H₂O (1) (H₂PDC = pyridine-3,5-dicarboxylic acid), have been synthesized under hydrothermal conditions, and characterized by elemental analysis, IR, thermogravimetric analysis and single-crystal X-ray diffraction. Complex 1 features an unusual three-dimensional network structure in which infinite gadolinium-carboxylate chains are linked by [Ag(PDC)₂]³⁻ metalloligands to form a mixed-metal coordination network. Moreover, the luminescent properties and magnetic properties of 1 have also been investigated.     

Rupture Pathway of Phosphatidylcholine Liposomes on Silicon Dioxide

We have investigated the pathway by which unilamellar POPC liposomes upon adsorption undergo rupture and form a supported lipid bilayer (SLB) on a SiO₂ surface. Biotinylated lipids were selectively incorporated in the outer monolayer of POPC liposomes to create liposomes with asymmetric lipid compositions in the outer and inner leaflets. The specific binding of neutravidin and anti-biotin to SLBs formed by liposome fusion, prior to and after equilibrated flip-flop between the upper and lower monolayers in the SLB, were then investigated. It was concluded that the lipids in the outer monolayer of the vesicle predominantly end up on the SLB side facing the SiO₂ substrate, as demonstrated by having maximum 30–40% of lipids in the liposome outer monolayer orienting towards the bulk after forming the SLB.     

水辅助注塑聚丙烯制品的晶体结构研究

通过偏光显微镜(PLM)观察了水辅助注塑(WAIM)聚丙烯(PP)制品靠近注水喷嘴和远离注水喷嘴两个位置的晶体结构,发现WAIM制品沿壁厚方向都可以分为表层、中芯层和水道层,并且发现两个位置水道层和中芯层的晶体结构比较相似,表层晶体结构出现了较大的差异;靠近注水喷嘴位置表层晶体结构出现明显的取向现象,而在远离注水喷嘴位置没有出现。在晶体结构分析的基础上,初步探讨了水辅助注塑制品晶体结构的形成机理。结果表明:水的穿透对于熔体内部剪切的增加和取向结晶的形成有明显的促进作用。     

Evaluation of glass-forming ability of binary metallic glasses with liquidus temperature, crystallographic data from binary phase diagrams and molecular dynamics simulations

The glass-forming ability (GFA) of binary metallic glasses was analyzed with data for the liquidus temperature (T_l) acquired as a function of composition from binary phase diagrams, assisted by crystallographic data combined with amorphous-forming composition range (AFCR) and molecular dynamics (MD) simulations. A necessary condition for the formation of bulk metallic glasses (BMGs) was determined as ΔT_l ≥ 300 K where ΔT_l was defined as a decrease in T_l due to eutectic reaction. The crystalline compounds with structure types of bcc or its derivative type, such as CsCl (B2), CrB (B_f), Al₂Cu (C16) and MoSi₂ (C11_b), tended to be found in AFCR frequently. The total pair-distribution and interference functions revealed a high forming tendency of a noncrystalline Cu₁₀Zr₇ structure created by MD. Simultaneous achievements of the Cu₁₀Zr₇ structure for crystallographic features resulting from the bcc family structure and geometrical features in phase diagram for T_l affect the formation of Cu_61.8Zr_38.2 BMG.