Transport numbers of H+ and O2- in the electrochemical system (H2 + H2O),Me/BaCe0.9Nd0.1O3-α/Me,(H2 + H2O)

In the temperature range 873–1123 K, transport numbers of oxygen ions and protons are determined in the system (H₂ + H₂O), Me/BaCe_0.9Nd_0.1O_3-α/Me,(H₂ + H₂O), where Me = Ag, Au, Pt, Ni, by the emf and current methods. The determined transport numbers are independent of the determination method, the electrode material, the current direction (anodic and cathodic polarization of the electrode), polarizability of electrodes, and the partial water (hydrogen) pressure in the gas phase. This unambiguously suggests that the transport numbers refer to the solid electrolyte, and not the electrochemical system as a whole. It also follows that partial currents of the hydrogen ionization and the oxygen ion discharge are determined by the transport numbers of protons and oxygen ions in the electrolyte. At a constant temperature, their ratio is affected by neither the electrode potential nor the gas phase composition, i.e., both electrode reactions have a common limiting step (or steps). Deceased.     

Fe2O3/CNT催化湿法H2O2氧化苯酚

通过化学沉积法和热处理得到多壁碳纳米管负载Fe2O3催化剂 Fe2O3/CNT, Fe2O3的负载质量分数约为15.1%,XRD表征显示,负载的Fe2O3存在α和γ这2种晶型。考察了Fe2O3/CNT催化湿式H2O2氧化去除废水中苯酚催化性能,通过苯酚的去除率及反应过程中催化剂活性组分的溶出总量,研究了催化剂制备过程中添加聚乙烯醇对催化剂性能的影响。在苯酚和H2O2初始浓度分别为350和1 500 mg/L、催化剂投加量为1.0 g/L、温度80 ℃条件下,经过240 min的反应,苯酚去除率达100％,COD去除率为86.1％。     

NaBrO3/NaHSO4 · H2O as a Versatile Reagent System for the Oxidation of Benzylic Alcohols and Aldehydes

The oxidation of benzylic alcohols and aldehydes by NaBrO₃ is efficiently promoted in the presence of NaHSO₄ · H₂O. All reactions were performed under mild and completely heterogeneous conditions in good to high yields.     

Chemoselective Reduction and Transesterification of α-Keto Propargylic Esters Mediated by NaBH4 and CeCl3 · 7H2O

An efficient one-pot synthesis of α -hydroxy propargylic esters by chemoselective reduction followed by transesterification using NaBH₄ in combination with CeCl₃ · 7H₂O is described.

CO/H2O/O2直接法制过氧化氢的环境友好纳米Cu/Al2O3催化剂

采用液相化学还原法制备了系列用于一氧化碳、水及氧气直接法制过氧化氢的环境友好纳米Cu/Al2O3催化剂,并用TEM,XRD和N2O化学滴定等手段对催化剂中纳米金属铜的结构及性质进行了表征.研究结果表明,Cu/Al2O3催化剂在CO/H2O/O2直接法制H2O2反应中呈现出显著的纳米尺寸效应当金属铜纳米晶粒平均尺寸为15 nm时,有高达0.236 mmol·(g-cat)-1·h-1的H2O2生成速率.     

Thermodynamic properties of two zinc borates: 3ZnO·3B2O3·3.5H2O and 6ZnO·5B2O3·3H2O

Two pure zinc borates with microporous structure 3ZnO·3B₂O₃·3.5H₂O and 6ZnO·5B₂O₃·3H₂O have been synthesized and characterized by XRD, FT-IR, TG techniques and chemical analysis. The molar enthalpies of solution of 3ZnO·3B₂O₃·3.5H₂O(s) and 6ZnO·5B₂O₃·3H₂O(s) in 1 mol · dm⁻³ HCl(aq) were measured by microcalorimeter at T = 298.15 K, respectively. The molar enthalpies of solution of ZnO(s) in the mixture solvent of 2.00 cm³ of 1 mol · dm⁻³ HCl(aq) in which 5.30 mg of H₃BO₃ were added were also measured. With the incorporation of the previously determined enthalpy of solution of H₃BO₃(s) in 1 mol · dm⁻³ HCl(aq), together with the use of the standard molar enthalpies of formation for ZnO(s), H₃BO₃(s), and H₂O(l), the standard molar enthalpies of formation of −(6115.3 ± 5.0) kJ · mol⁻¹ for 3ZnO·3B₂O₃·3.5H₂O and −(9606.6 ± 8.5) kJ · mol⁻¹ for 6ZnO·5B₂O₃·3H₂O at T = 298.15 K were obtained on the basis of the appropriate thermochemical cycles.     

Hydrothermal Synthesis and Structure of A Novel Organic–Inorganic Hybrid Polyoxotungstate: H5[Cu(en)2H2O]{Cu(en)2[P2W19O69(H2O)]} · 2.5H2en · 8H2O

Abstract  A novel polyoxotungstate H₅[Cu(en)₂H₂O]{Cu(en)₂[P₂W₁₉O₆₉(H₂O)]} · 2.5H₂en · 8H₂O (1) has been synthesized under hydrothermal conditions and characterized by IR spectroscopy, elemental analysis, and single crystal X-ray structural analysis. Crystal data for 1: Triclinic, P-1, a = 12.673(6) ?, b = 20.147(10) ?, c = 20.514(11) ?, α = 110.432(7)°, β = 90.171(5)°, γ = 97.502(6)°, V = 4859(4) ?³, Z = 2. Compound 1 exhibits a 1D linear structure, in which the [Cu(en)₂]²⁺ ions act as the linkages of {P ₂ W ₁₉ } lacunary units. Graphical Abstract  A novel polyoxotungstate H₅[Cu(en)₂H₂O]{Cu(en)₂[P₂W₁₉O₆₉(H₂O)]} · 2.5H₂en · 8H₂O has been made under hydrothermal conditions. Compound 1 exhibits a 1D linear structure based on the {P ₂ W ₁₉ } lacunary units linked by the [Cu(en)₂]²⁺ bridging groups.      

Synthesis and Crystal Structure of （H3O）2[Cu3Cl3（H2O）3（NC9H12.5O6）2]

1 INTRODUCTION The polydentate ligand nitrilotripropionic acid, H3ntp[N(CH2CH2COOH)3], has attracted conside- rable research interest in constructing coordination polymers, designing organic-inorganic hybrid mate- rials[1], synthesizing supramolecular compounds[2], etc. due to its high degree of flexibility with three carboxylic acid moieties allowing for a variety of coordination through oxygen atoms[3]. It also pro- vides other versatile properties such as the possibili- ty of inter-…     

Synthesis and thermochemical characteristics of Na2O · Al2O3 · 2.5H2O

A pure phase of monosodium aluminate hydrate Na₂O · Al₂O₃ · 2.5H₂O (MAH) is synthesized and characterized by means of XRD, IR, SEM, TGA, and DSC. The heat capacity of the compound is measured in the temperature range of ?100 to 100°C, and the thermal contributions to enthalpy and entropy are calculated. The standard entropy, enthalpy, and Gibbs energy of formation of MAH at 298 K are estimated.     

Syntheses and structures of p-HOOCC6F4COOH · H2O (H2L · H2O) and luminescent coordination polymers [Tb2(H2O)4(L)3 · 2H2O] n and Tb2(Phen)2(L)3 · 2H2O

Compounds p-HOOCC₆F₄COOH · H₂O (H₂L · H₂O), [Tb₂(H₂O)₄(L)₃ · 2H₂O] _n (I), and Tb₂(Phen)₂(L)₃ · 2H₂O (II) are synthesized. According to the X-ray structure analysis data, the crystal structure of H₂L · H₂O is built of centrosymmetric molecules H₂L and molecules of water of crystallization. The crystal structure of compound I is built of layers of coordination 2D polymer [Tb₂(H₂O)₄(L)₃] _n and molecules of water of crystallization. The ligands are the L^2? anions performing both the tetradentate bridging and pentadentate bridging-chelating functions. The coordination polyhedron TbO₉ is a distorted three-capped trigonal prism. Acid H₂L manifests photoluminescence in the UV region (??_max = 368 nm). Compounds I and II have the green luminescence characteristic of the Tb³⁺ ions, and the band with ??_max = 545 nm (transition ⁵ D ₄?? ⁷ F ₅) is maximum in intensity. The photoluminescence intensity of compound II is higher than that for compound I.     

Glycerin and CeCl3 · 7H2O: A New and Efficient Recyclable Reaction Medium for the Synthesis of Quinoxalines

An efficient and environmentally benign process for the synthesis of quinoxalines has been developed using glycerine–cerium chloride as a reaction medium. This method is applicable to a variety of diketones and 1,2-phenylenediamines to afford the corresponding quinoxaline derivatives in excellent yields. The reaction medium was recovered and reused for further reactions without any problem.     

La2O3对Pd/Al2O3催化蒽醌氢化制H2O2性能的影响

 采用湿浸法制备了用于蒽醌氢化制H2O2的La2O3促进的Pd/Al2O3催化剂,并考察了不同La2O3含量对催化性能的影响. 采用XRD,N2物理吸附,CO2-TPD,H2-O2滴定和电子探针等技术对催化剂进行了表征. 结果表明,加入适量的La2O3能够抑制高温焙烧时Al2O3晶粒的长大,增大催化剂的比表面积,提高金属Pd的分散度,增强载体表面碱性,提高催化剂表面的Pd浓度,减小Pd层厚度,从而提高催化剂的氢化活性. 加入La2O3可使催化剂的Pd负载量由0.281%降至0.188%,而催化剂活性提高了44%.     

Structure of (C3H5NH3)2H2P2O7·H2O

The bis(cyclopropylammonium)dihydrogenodiphosphate monohydrate is a new diphosphate associated with the organic molecule C₃H₅NH₂. We report the chemical preparation and the crystal structure of this organic cation diphosphate. (C₃H₅NH₃)₂H₂P₂O₇.H₂O is orthorhombic (S.G. : P2₁2₁2₁), with Z = 4 and the following unit-cell parameters : a = 4.828(1) Å, b = 11.011(1) Å, c = 25.645(2) Å. The P₂O₇ groups and H₂O water molecules form a succession of bidimensional layers perpendicular to the c axis. The organic cations ensure the three-dimensional cohesion by NH-O hydrogen bonds.     

NH2SO3H and H6P2W18O62 · 18H2O-Catalyzed,Three-Component,One-Pot Synthesis of Benzo[c]acridine Derivatives

We report here two simple methods for the synthesis of benzo[c]acridine derivatives from three-component, one-pot condensation of 1-naphthylamine, dimedone, and a variety of substituted aldehydes in the presence of a catalytic amount of NH₂SO₃H or H₆P₂W₁₈O₆₂ · 18H₂O under solvent-free conditions at 120 °C or in refluxing ethanol.     

Two Light-Metal Dihydrogenisocyanurate Hydrates Linked by Diagonal Relationship: Syntheses,Crystal Structures,and Vibrational Spectra of Li[H2N3C3O3]·1.75 H2O and Mg[H2N3C3O3]2·8 H2O

Single-crystalline materials of Li[H₂N₃C₃O₃] · 1.75 H₂O and Mg[H₂N₃C₃O₃]₂ · 8 H₂O were obtained by dissolving stoichiometric amounts of the respective carbonates with cyanuric acid in boiling water followed by gentle evaporation of excess water after cooling to room temperature. Even though both of these compounds crystallize in the triclinic space group P1 according to X-ray structure analyses of their colorless and transparent single crystals, they adopt two new different structure types. Li[H₂N₃C₃O₃] · 1.75 H₂O exhibits the unit-cell parameters a = 884.71(6) pm, b = 905.12(7) pm, c = 964.38(7) pm, α = 67.847(2)°, β = 62.904(2)° and γ = 68.565(2)° (Z = 4), whereas the lattice parameters for Mg[H₂N₃C₃O₃]₂ · 8 H₂O are a = 691.95(5) pm, b = 1055.06(8) pm, c = 1183.87(9) pm, α = 85.652(2)°, β = 83.439(2)° and γ = 79.814(2)° (Z = 2). In both cases, the singly deprotonated isocyanuric acid forms monovalent anions consisting of cyclic [H₂N₃C₃O₃]^– units, which are arranged in ribbons typical for most hitherto known monobasic isocyanurate hydrates. The structures are governed by the oxophilic strength of the respective cation which means that they fulfil their oxophilic coordination requirements either solely with water molecules ([Mg(OH₂)₆]²⁺ for Mg²⁺) or with crystal water and one or two direct coordinative contacts to carbonyl oxygen atoms (O_(cy)) of [H₂N₃C₃O₃]^– anions ([(Li(OH₂)_2–3(O_(cy)1–2]⁺ for Li⁺). In both structures occur dominant hydrogen bonds N–H ··· O within the anionic [H₂N₃C₃O₃]^– ribbons as well as hydrogen bonds O–H ··· O between these ribbons and the hydrated Li⁺ and Mg²⁺ cations.     

Two binuclear complexes containing the enrofloxacinate anion: Cd2(C19H21N3O3F)4(H2O)2 · 4H2O and Pb2(C19H21N3O3F)4 · 4H2O

The syntheses and crystal structures of the closely related but non-isostructural Cd₂(C₁₉H₂₁N₃O₃F)₄(H₂O)₂?·?4H₂O (1) and Pb₂(C₁₉H₂₁N₃O₃F)₄?·?4H₂O (2) are described, where C₁₉H₂₁N₃O₃F^? is enrofloxacinate (enro). Both compounds contain centrosymmetric, binuclear, neutral complexes incorporating a central diamond-shaped M₂O₂ (M?=?Cd, Pb) structural unit. The Cd²⁺ coordination polyhedron in 1 is a CdO₆ trigonal prism, including one coordinated water. The Pb²⁺ coordination polyhedron in 2 can be described as a very distorted square-based PbO₅ pyramid, although two additional short Pb?···?O (<3.1?Å) contacts are also present. In the crystal of the cadmium complex, O–H?···?O hydrogen bonds lead to a layered structure. In the lead compound, O–H?···?O and O–H?···?N interactions lead to chains in the crystal. Crystal data: 1: C₇₆H₉₆Cd₂F₄N₁₂O₁₈, M _r?=?1766.45, triclinic, P 1, a?=?12.185(2)?Å, b?=?12.306(3)?Å, c?=?14.826(3)?Å, α?=?68.15(3)°, β?=?70.28(3)°, γ?=?86.11(3)°, V?=?1938.2(7)?ų, Z?=?1, T?=?298 K, R(F)?=?0.030, wR(F ²)?=?0.079. 2: C₇₆H₈₈F₄N₁₂O₁₆Pb₂, M _r?=?1920.00, triclinic, P 1, a?=?12.0283(4)?Å, b?=?12.7465(4)?Å, c?=?13.0585(4)?Å, α?=?83.751(1)°, β?=?74.635(1)°, γ?=?81.502(1)°, V?=?1904.3(1)?ų, Z?=?1, T?=?298?K, R(F)?=?0.021, wR(F ²)?=?0.049.