高荧光性含锌类水滑石研究

本研究将适量锌离子(II)取代镁铝水滑石中的镁离子(II), 以及将一定量的8-羟基喹啉(8-hydroxyquinoline)分散于镁铝水滑石层间的亲油性阴离子中, 使与其板层表面上的锌离子配位, 经共沉淀法, 合成、组装得到一类迄今未见报道的具高荧光性的类水滑石(Zn-HTLC)荧光材料. 采用荧光光谱、红外光谱、紫外光谱、X射线衍射和热分析等对其进行了表征. 研究表明, 这种类水滑石在紫外光下可发出强烈的蓝绿色荧光(501 nm), 荧光强度高达4.5×10⁵ a.u., 说明锌离子(II)分散于类水滑石的氢氧化镁板层中, 可有效防止发光结构单元的荧光猝灭, 而且溶于层间阴离子中的配体与板层上的锌离子(II)配位所形成的特殊组装结构, 增强了发光中心的不对称性, 也是其具有高荧光性的可能原因. 热分析结果显示, 这种类水滑石耐热性强, 有望应用于各种功能性荧光材料.     

层状K4Ag2Sn3S9·2H2O的溶剂热合成与表征

用溶剂热法合成了K4Ag2Sn3S9·2H2O,通过单晶X射线衍射、DSC、TG、IR和紫外漫反射光谱等手段对其进行了表征.结果表明,K4Ag2Sn3S9·2H2O属单斜晶系,P21/m空间群,a=0.78071(2)nm,b=2.73508(1)nm,c=1.05008nm,α=90°,β=103.87(6)°,γ=90°,Z=4.其层状结构内具有一维孔道,钾离子分离在层间及层内孔道中.     

Analysis of silicon carbonitride films by laser mass spectrometry

The possibilities of laser mass spectrometry in determining the main composition of silicon carbonitride films (SiC _x N _y ) deposited on a substrate made of germanium and gallium arsenide are considered. The conditions of laser sampling were selected and the instrument was adjusted to identify the major components of films synthesized by the plasma deposition. The instrument was calibrated by neat silicon compounds to obtain quantitative data on the concentrations of carbon, nitrogen, oxygen, and silicon. A calibration method was proposed, and the concentration of hydrogen in the layers of silicon carbonitride was estimated.     

Surface and interface analysis of titanium nitride diffusion barriers

Titanium nitride films were produced on silicon substrate by ion beam assisted deposition in the alternate mode: first, thin titanium layers were deposited by electron beam evaporation and then titanium nitride was formed by nitrogen implantation at room temperature; this cycle was then iterated many times in order to obtain thicker titanium nitride layers. The obtained films were characterized with respect to atomic composition by Rutherford backscattering spectrometry and nuclear reaction analysis techniques, while chemical bonding was investigated by Auger line-shape analysis. We observe that nitrogen implantation, along with the production of titanium nitride, induces silicon migration into the film. Silicon transport is connected to point defects produced by ion implantation as well as by chemical driving forces associated with silicides formation.     

Cs2USi6O15: a tetravalent uranium silicate

A uranium(IV) silicate has been synthesized under high-temperature, high-pressure hydrothermal conditions. The structure consists of unbranched dreier single layers with the composition [Si(2)O(5)] that are connected by UO(6) octahedra to form a 3D framework with 7-ring channels where the Cs(+) cations are located. Each UO(6) octahedron spans four neighboring dreier single chains and, therefore, introduces a high degree of corrugation in the silicate layers. The U 4f X-ray photoelectron spectroscopy spectrum was measured to confirm the valence state of the uranium. A comparison of related metal silicate structures is made. After the synthesis of this compound, all members in the family of uranium silicates and germanates with oxidation states of uranium from 4+ to 6+ have been observed.     

Structural and phase transformations and hardness of ceramics produced by high-temperature zirconium nitriding

Resistive heating of zirconium in a gaseous nitrogen atmosphere yields ceramics based on zirconium nitride with a heterophase structure. X-ray powder diffraction analysis determined the compositions of phases of the synthesized ceramics. The surface of the material consists of zirconium nitride close in composition to ZrN. In the bulk of the materials, in shallower layers, a nitrogen-deficient nitride phase forms, and in deeper layers, a phase of solid solution of nitrogen in zirconium does. The hardness of ceramics based on heterostructures of the type Zr_{solid solution}/ZrN_1–x /ZrN was studied. Changes in the structure and phase composition during high-temperature nitriding of zirconium foil at 1500 and 2400°C were described.     

Intercalation of magnesium into a graphite-like layered material of composition BC2N

Magnesium was intercalated into a graphite-like layered material with an approximate composition of BC(2)N. The obtained material was a second-stage compound with a d-spacing of 0.367 nm for the intercalated layers. This is the first example of magnesium intercalation into a graphite-network-based material.     

[（Mo2O6）（pyrazine）]的水热合成、晶体结构和热性能研究

用吡嗪-2,3-二羧酸、CoCl2·6H2O、MoO3和去离子水在413K下通过水热反应法得到了标题化合物[（Mo2O6）（pz）],该化合物晶体属于正交晶系,空间群为Pbca,晶胞参数为α=0．75778（15）nm,b=0．74057（15）nm,c=1．4112（3）nm,Z=4．单晶衍射数据表明标题化合物由二齿桥联配体吡嗪将二维网状[Mo2O6]。连接成具有三维网络结构的无机一有机杂化化合物,其中每个Mo原子以变型八面体构型和5个氧原子以及1个氮原子配位．标题化合物在300℃之前热性能稳定．     

Extraction of Iridium(IV) from Hydrochloric Acid Solution with Bis(piperidinoethylthioethyl)-1-phenyl-1-ethanone

A bidentate organic compound containing nitrogen and sulfur donor atoms was tested as a reagent for extraction of iridium(IV) from aqueous solutions. The composition of the extractable Ir(IV) complex was determined by ¹H NMR, UV, and IR spectroscopy and elemental analysis.     

Characterization of sugar juice heat exchanger tube deposit

Fouling of heat exchanger surfaces during sugar manufacture reduces productivity and increases energy demand. This study characterizes a deposit (including its internal structure) formed in a sugar factory's evaporator unit using a variety of X‐ray diffraction and scanning electron microscopy techniques (including X‐ray powder diffraction, X‐ray fluorescence, elemental mapping with energy dispersive spectroscopy and backscattered electron imaging). Calcium sulfate dihydrate, calcium oxalate mono‐ and dihydrate, hydroxyapatite, amorphous silica and organic matter are present in the deposit. The composition of the deposit (which contains three layers) varies along the height of the tube. There are noticeable differences in the composition and porosity among the layers in the deposit. A porous structure consisting of a mixture of amorphous silica, calcium oxalate dihydrate and organic matter is attached to the surface of the deposit in contact with sugar juice, while a denser morphology of amorphous silica and hydroxyapatite is attached to the tube wall. Elemental mapping identifies an association between Si, Al, Mg, Fe and O, suggesting the presence of a silicate compound as a minor component in the deposit. An attempt is made to rationalize the formation of the observed phases. Copyright © 2010 John Wiley & Sons, Ltd.     

Characterization of titanium nitride films and sputter target material by 14 MeV neutron activation analysis

Titanium nitride films /3.0 and 3.8 microns/ deposited by the magnetron sputtering technique on silicon substrates and the commercially procured compound sputter target material are characterized for their bulk compositions by non-destructive 14 MeV neutron activation analysis /NAA/. The practical sensitivity and precision obtained under the present experimental conditions are 0.7 mg and 5% in the case of titanium and 0.1 mg and 8% in the case of nitrogen, respectively. The bulk composition of the films seems to conform to stoichiometric nitride, TiN, while the presence of oxygen could not be precluded in the compound target material.     

New synthetic approach to yttrium hydroxoacetates, structural characterization, and use as a precursor for coated conductors

A novel synthetic approach is given for the preparation of a metal-organic lanthanide sol-gel precursor solution and its application for the production of coated conductors. Besides all other problems concerning the technical process itself, the key to a successful deposition of oxide layers is the choice of the precursor solution and the understanding of the mechanism of deposition. Moreover, the isolation and characterization of the species involved in the reaction is very important. Regarding the complex process occurring during the formation of the surface layer, it is obvious that the best choice should have a compound already containing the final composition of the layer. Two compounds of composition [Y(OAc)3(H2O)2]2 and [Y(OAc)3]2(H2O) were isolated from their precursor solution and characterized by X-ray structural analysis. A short outlook will give an insight into the possible bonding mechanisms of the surface layer. These experiments were made with the mixed metal-oxide system yttrium-stabilized zirconium oxide, which is widely used as a substrate for superconducting oxides. A study of the structure of hydrated yttrium acetates, by single-crystal X-ray diffraction, infrared spectra, and elemental analysis demonstrates that there are two separate structures for hydrated yttrium acetates, which play a role as an intermediate in the building of ceramic oxide layers for coated conductors.     

Redetermination of CaMn2O4

The title compound, calcium dimanganese tetraoxide, CaMn₂O₄, was synthesized hydro­thermally and is made up of edge‐sharing Mn³⁺ distorted octahedral layers and eight‐coordinate Ca²⁺ centered polyhedral layers.     

Investigations on the synthesis, structures, and properties of new copper(I) 2,3-dimethylpyrazine coordination compounds

Five new coordination compounds were prepared, structurally characterized, and investigated for their thermal properties. In the structure of the ligand-rich 4:9 compound, tetra(mu2-chloro)bis(mu2-2,3-dimethylpyrazine-N,N')tetrakis(2,3-dimethylpyrazine-N)tetracopper(I) tris(2,3-dimethylpyrazine)solvate (I), discrete complexes are formed by build up of two [(CuCl-(2,3-dimethylpyrazine)2]2 dimers, which are connected by two 2,3-dimethylpyrazine ligands via mu-N,N' coordination. In the 1:1 compound poly[mu2-chloro-mu2-2,3-dimethylpyrazine-N,N'-copper(I)] (II), (CuCl)2 dimers are found, which are connected by the 2,3-dimethylpyrazine ligands into layers. For this composition, a second polymorphic modification was found (III), which exhibits a different topology of the coordination network and a different packing of the layers. In the most stable 3:2 compound catena[tri(mu2-chloro)bis(mu2-2,3-dimethylpyrazine-N,N')tricopper(I)] (IV), six-membered rings of (CuCl)3 are found, which are connected by the 2,3-dimethylpyrazine ligands into chains. In the ligand-deficient 2:1 compound, poly[di(mu3-chloro)(mu2-2,3-dimethylpyrazine-N,N')dicopper(I)] (V), CuCl double chains are found, which are connected by the 2,3-dimethylpyrazine ligands into layers. On heating, compound I transforms quantitatively into the 3:2 compound IV without the formation of II or III as intermediates. Compound IV is also obtained by heating either the 1:1 compound II or III. On further heating, the 3:2 compound IV loses additional ligands, forming the ligand-deficient 2:1 compound V, which then decomposes into CuCl. The stability, thermal reactivity, and the transition behavior of all compounds were investigated using different thermoanalytical methods. These results are compared with those previously reported for the structurally similar CuCl(2-ethylpyrazine) coordination compounds. The formation and the stability of the different compounds in solution were also investigated.     

Automation in organic analysis II. Simultaneous microdetermination of oxygen and nitrogen

A simple, rapid, and accurate method of simultaneous determination of oxygen and nitrogen in organic compounds, containing (in addition to C, H, and O) Cl, Br, and I, is described. The principle of the method consists in the pyrolytic decomposition of the analyzed compound in a current of hydrogen at 1000–1100 °C and the conducting of the hydropyrolytic product through layers of nickel and platinized carbon (50% Pt) heated at 1050 °C. On this filling the nitrogen-containing products are transformed to elementary nitrogen, the oxygen-containing products are transformed to carbon monoxide, the halogens to hydrohalogenides, and methane is decomposed. After removing hydrohalogenides by soda asbestos, carbon monoxide and nitrogen are separated on a chromatographic column filled with Porapak Q, and determined with a catharometer. The whole analysis, including the weighing of the sample, requires 25 min. Sulfur interferes with the determination.     

溶胶凝胶复合材料的研究及对生物酶的固定

研究了一种新型的氧化铝/聚乙二醇（Al2O3/PEG）溶胶凝胶复合材料,利用红外光谱、探针电镜对材料的性能进行了表征。试验结果表明：复合膜中含有大量的羟基和氢键,且两种组分形成互穿网络,该材料刚柔相济的特点使其适合于做生物传感器的固定化材料。PEG是极性高聚物,在溶胶凝胶的体系中,可以起到加速反应及防止膜开裂的作用。Al2O3/PEG复合材料对酶具有较好的生物相容性和较高的稳定性,将生物酶固定其中制备成的生物传感器具有良好的反应活性,同时,还证明了这种生物传感器具有稳定性和灵敏度高的特点。     

NaGaS2: An Elusive Layered Compound with Dynamic Water Absorption and Wide-Ranging Ion-Exchange Properties

Most ternary sulfides belonging to the MGaS₂ structure-type have been known for many years and are well-characterized. Surprisingly, there have been no reports of the NaGaS₂ composition, which contains Na, a monovalent cation slightly larger in size than Li, found in LiGaS₂, a compound known for its non-linear optical properties. Now it is demonstrated for the first time that the unique reversible water absorption in NaGaS₂ has resulted in its absence from previous reports owing to difficulties encountered when characterizing this compound by SC XRD. The layered structure of this compound coupled with uniquely easy migration of water molecules between the layers allows for ion exchange with 3d and 5f metal cations. Some cations, for example, Ni²⁺, facilitate exfoliation of the layers, providing a facile synthetic route to a new class of 2D chalcogenide materials and furthermore demonstrating that NaGaS₂ can readily uptake uranyl species from aqueous solutions.     

Interaction of ester functional groups with aluminum oxide surfaces studied using infrared reflection absorption spectroscopy

The bonding of two types of ester group-containing molecules with a set of different oxide layers on aluminum has been investigated using infrared reflection absorption spectroscopy. The different oxide layers were made by giving typical surface treatments to the aluminum substrate. The purpose of the investigation was to find out what type of ester-oxide bond is formed and whether this is influenced by changes in the composition and chemistry of the oxide. The extent by which these bonded ester molecules resisted disbondment in water or substitution by molecules capable of chemisorption was also investigated. The ester groups were found to show hydrogen bonding with hydroxyls on the oxide surfaces through their carbonyl oxygens. For all oxides, the ester groups showed the same nu(C = O) carbonyl stretching vibration after adsorption, indicating very similar bonding occurs. However, the oxides showed differences in the amount of molecules bonded to the oxide surface, and a clear relation was observed with the hydroxyl concentration present on the oxide surface, which was determined from XPS measurements. The two compounds showed differences in the free to bonded nu(C = O) infrared peak shift, indicating differences in bonding strength with the oxide surface between the two types of molecules. The bonding of the ester groups with the oxide surfaces was found to be not stable in the presence of water and also not in the presence of a compound capable of chemisorption with the aluminum oxide surface.     

Chelating Polymers. II. Amino Acetic Acid Chelating Polymers Derived from Hydroxyarylamino Acetic Acids

The prototype dimeric chelating compounds 3,3′-methylenebis-[N(4-hydroxyphenyl) iminodiacetic acid] and 3,3′-methylenebis-[N(4-methoxyphenyl) iminodiacetic acid] were synthesized and characterized by composition analysis, infrared spectroscopy, and potentiometric titration data. Their chelating characteristics with Cu(II), Ni(II), Co(II), and Zn(l1) ions were established by composition analysis and comparative infrared spectroscopy.

The results suggest chelation and structures of the usual iminodiacetatometal complex type for the Ni(II), Co(II), and Zn(I1) compounds of 3,3′methylenebis-[N-(4-hydroxyphenyl) iminodiacetic acid] and for the Cu(I1, Ni(II), and Co(I1) compounds of 3,3′-methylenebis-[N-(4-methoxyphenyl) iminodiacetic acid]. The composition analysis of each of these compounds indicates 1:2:2 mole ratios of ligand to metal ion to water. Square planar structures are proposed wherein the two iminodiacetatometal chelate moieties are essentially independent of each other.

The composition analysis of the Cu(II) compound of 3,3′-methylenebis-[N-(4-hydroxyphenyl) iminodiacetic acid] indicates a 1:2:1 mole ratio of ligand to metal ion to water. Structures are proposed in which some of the carboxylate groups are bridges between two metal coordination centers.

The composition analysis of the Zn(II) compound of 3,3′-methylenebis-[N-(4-methoxyphenyl) iminodiacetic acid] indicates a 1:1 mole ratio of ligand to metal ion. A structure is proposed in which both nitrogen atoms and two of the four carboxylate groups of the dimeric ligand are coordinated to the same metal ion.

A preliminary investigation was made of oligomeric compounds analogous to the prototype dimeric compounds.     

Complexation of Hg(II) with Iodide and Ammonia in Alkaline Solutions

Reactions of K₂HgI₄ with NaOH and NH₃ are studied. A poorly soluble compound with the composition NHHg₂IOH and colored soluble polymeric complexes containing nitride nitrogen, formed in complex autocatalytic reactions, are characterized.