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1.
Shifts of chromatographic peak maxima and centres of gravity have been investigated for different amounts of propane injected on to a chromatographic column in ideal, non-linear chromatography. Specific retention volumes (V g (273), corrected to the standard temperature, 273.15 K), propane adsorption isotherms, and the first and second derivatives of the isotherms, (da/dp) T and (d2a/dp2) T , were determined for samples of active carbon and for different amounts of propane injected on column. Relationships between specific retention volume and the molar differential work of adsorption, A, were calculated on the basis of the propane isotherms and using the retention times of the peak maxima and the centres of gravity of the peaks. The equations obtained, ln V g (273)=f1(A) and(dW/dA) T, F c = f2(ln V g (273)), have been used to explain the relationships between (i) chromatographic peak profiles and (ii) the distribution function of pore volumes filled with propane and the molar differential work of adsorption at different column temperatures (303–318 K).  相似文献   

2.
X-ray structural analysis has been performed for two complex compounds: Cu(en)2(o-HB)2H2O (I) (a = 16.873(4) Å, b = 8.713(2) Å, c = 14.803(3) Å, β = 91.15(2)°, V = 2175.8(8) Å3, C2/c, Z = 4, R(F) = 0.0263, 1516 reflections with I > 3σ (I)) and [Cu(en)2(OH2)2]2+(o-AB?)2 (II) (a = 7.488(5) Å, b = 22.122(8) Å, c = 7.856(5) Å, β = 118.77(2)°, V = 1140.7(11) Å3, P21/n, Z = 2, R(F) = 0.0432, 1684 reflections with I > 3σ(I)) synthesized under identical conditions (en is ethylenediamine, o-HB is o-hydroxybenzoate, and o-AB is o-aminobenzoate). Although the compounds were assumed to have similar structures and the Cu-Lig bond lengths and the cis and trans angles are acceptable for an octahedral structure, the geometric parameters of o-HB suggest that the copper atom has a plane square environment.  相似文献   

3.
The inclusion compound of zinc lactate terephthalate with R-butan-2-ol, [Zn2(R-BusOH) (bdc)(S-lac)]?(R-BusOH) (BusOH is butan-2-ol, H2bdc is terephthalic acid, S-H2lac is lactic acid), was prepared by soaking crystals of [Zn2(dmf)(bdc)(S-lac)]?DMF in pure R-butan-2-ol. The positions of chiral alcohol molecules in voids of the chiral framework and the host–guest contacts were determined by X-ray diffraction. These data provide an explanation for the origin of chiral discrimination of zinc lactate terephthalate toward the R-isomer of butan-2-ol.  相似文献   

4.
The structure of trans-[RuNO(NH3)4(H2O)](NO3)3 (I) and trans-[RuNO(NH3)4(NO3)](NO3)2 (II) was determined by XRD. Crystallographic data are as follows: space group I41/a; a = b = 18.280(1) Å, c = 15.129(1) Å, R = 0.0244 (I), and space group Cm, a = 11.5620(3) Å, b = 7.9934(2) Å, c = 7.7864(2) Å, β = 127.124(1)°, R = 0.0139 (II). Interatomic distances for complex particles of fac- and mer- [RuNO(NH3)2(NO3)3] (III and IV, respectively) were determined by EXAFS.  相似文献   

5.
The structures of three novel octahedral rhenium cluster compounds [Re6S8(CN)2(py)4]·H2O (1), [Re6S8(CN)2(4-Mepy)4] (2), [Re6S8(CN)2(4-Mepy)4]·4-Mepy (3) (py = pyridine, 4-Mepy = 4-methylpyridine) are determined by X-ray crystallography. Crystal data are: C2/m space group, a = 14.813(1) Å, b = 14.772(1) Å, c = 9.2122(6) Å, β = 119.085(2)°, V = 1761.7(2) Å3, d x = 3.318 g/cm3, R = 0.0585 (1); I41/amd space group, a = 16.0018(3) Å, c = 14.7186(5) Å, V = 3768.81(16) Å3, d x = 3.169 g/cm3, R = 0.0489 (2); P21/c space group, a = 9.0452(4) Å, b = 15.8065(7) Å, c = 15.2951(6) Å, β = 103.700(2)°, V = 2124.57(16) Å3, d x = 2.957 g/cm3, R = 0.0245 (3). Molecular cluster complexes interact via π-π stacking affording 3D frameworks in 1 and 2 and chains in 3.  相似文献   

6.
Recurrent equations A(x + k) = aA(x) + b were shown to be applicable to the approximation not only of virtually arbitrary properties of organic compounds (A) in homologous series (A = n C, k = 1 or 2) but also of the dependences of chromatographic retention parameters on the number of carbon atoms in homologue molecules (A = t R). The same equations described the temperature dependences of retention times of arbitrary compounds under isothermal separation conditions in gas chromatography (x = T, k = ΔT = const) and the dependences of retention times on the concentration of an organic solvent as an eluent component (x = C, k = ΔC = const) under isocratic separation conditions in high performance liquid chromatography.  相似文献   

7.
In the present work, the dependence of photovoltaic parameters of laboratory-scale dye sensitized solar cells (DSSCs) on photoanode active area (A) and also the effect of using current collector on this dependency were investigated. Current collectors were applied, in the form of silver strips, on the edges of electrodes. Electrochemical impedance spectroscopy (EIS) and current-voltage (I-V) curve measurement were employed as characterizing methods. The role of current collector was to decrease the resistance against current collection from the surface of electrodes and thus to decrease series resistance of DSSCs. It was observed that all photovoltaic parameters, i.e., short circuit current density (J sc), open circuit voltage (V oc), fill factor (FF), and power conversion efficiency (η), decrease with increasing A. Applying current collector had no influence on photovoltaic parameters of smallest DSSC, but it improved the performance of larger DSSCs. Also, applying current collector caused the photovoltaic parameters of DSSCs to be less dependent on A. It was shown that A dependence of photovoltaic parameters was due to the effect of A on area-specific series resistance (r s) of DSSC. Also, the effect of current collector on A dependency of photovoltaic parameters was due to its effect on A dependency of r s.  相似文献   

8.
A complex [Zn(C8H7O3)2(H2O)2] (C8H8O3 is vanillin) has been synthesized and characterized by IR, elemental analysis, and X-ray diffraction single-crystal analysis. The crystals are monoclinic, space group C2/c, a = 22.236(8) Å, b = 10.594(2) Å, c = 7.8190(16) Å, α = 89.90(3)°, β = 106.87(4)°, γ = 89.99(3)°, V = 1762.6(8) Å3, Z = 4, F(000) = 832, S = 1.079, ρ c = 1.521g cm?3, R = 0.0221, R w = 0.0604, μ = 1.433 mm?1. The Zn2+ ion is six-coordinated with a distorted octahedron geometry. The complex forms a three-dimensional network through intermolecular hydrogen bonds. The thermal decomposition kinetics of the complex for the second stage was studied under non-isothermal conditions by the TG and DTG methods. The kinetic equation can be expressed as dα/dt = Ae?E/RT 2(1 ? α)[1 ? ln(1 ? α)]1/2. The kinetic parameters (E, A), activation entropy ΔS , and activation free-energy ΔG were also gained.  相似文献   

9.
Macrocyclic and supermolecular complexes [Cu2(NiL)2Cl4] (I) and [Cd2(CuL)2Cl4] (II) (H2L = 2,3-dioxo-5,6,14,15-dibenzo-1,4,8,12-tetraazacyclo-pentadeca-7,13-diene) have been synthesized and structurally determined by X-ray diffraction and IR spectrum. Complex I crystallizes in the monoclinic system with P21/n group, a = 10.9019(15), b = 14.3589(19), c = 12.4748(17) 0A, β = 108.645(2)°, Z = 4. Complex II crystallizes in the monoclinic system with P21/n group, a = 10.9784(16), b = 14.580(2), c = 12.8904(18) Å, β = 109.339(2)°, Z = 4.  相似文献   

10.
Four new low melting salts, “Ionic Liquids” consisting of the [CrIII(NCS)4(Phen)]? complex monoanion and imidazolium based cations A, with A = 1-ethyl-3-methylimidazolium (EMIm), 1-butyl-3-methylimidazolium (BMIm), 1,3-dimethyl-2,4,5-triphenylimidazolium (DML), and 1,2,3,4,5-pentamethyl-imidazolium (PMIm), were investigated. Single-crystal X-ray investigations established the structures of the four compounds. (EMIm)[Cr(NCS)4(Phen)] (I): triclinic, \(P\bar 1\), a = 8.1382(6), b = 10.4760(8), c = 16.003(1) Å, α = 90.330(4)°, β = 94.759(4)°, γ = 107.305(4)°, Z = 2, R 1(F)/wR 2(F 2) = 0.0650/0.1770; (BMIm)[Cr(NCS)4(Phen)] (II): triclinic, \(P\bar 1\), a = 8.5545(4), b = 9.8620(4), c = 16.6762(6) Å, α = 92.503(2)°, β = 97.517(2)°, γ = 91.249(2)°, Z = 2, R 1(F)/wR 2(F 2) = 0.0393/0.0848; (DML)[Cr(NCS)4(Phen)] · C3H6O (III): triclinic, \(P\bar 1\), a = 11.0475(9), b = 13.589(1), c = 14.582(1) Å, α = 83.013(4)°, β = 87.116(4)°, γ = 70.333(5)°, Z = 2, R 1(F)/wR 2(F 2) = 0.0407/0.1023; (PMIm)[Cr(NCS)4(Phen)] · C3H6O (IV): orthorhombic, Pbca, a = 17.379(1), b = 16.514(1), c = 22.304(1) Å, Z = 8, R 1(F)/wR 2(F 2) = 0.0460/0.1107 (in addition III and IV contain co-crystallized acetone molecules). Each compound was characterized by elemental analysis, NMR, IR, und UV-Vis spectroscopy. Magnetic properties were derived from NMR investigations (EVANS method). All four compounds are paramagnetic with effective magnetic moments of spin-only CrIII. Melting points were obtained from DSC measurements. All melting points are higher than required for “Ionic Liquids”, but nevertheless “low” for molten salts.  相似文献   

11.
The products of 4′,5′-dibromobenzo-15-crown-5 (I) cyanation by the Rosenmund-Braun reaction are studied by the 1H NMR and IR spectroscopy methods. X-ray diffraction analysis of two isolated products, i.e., di(4′,5′-dicyanobenzo-15-crown-5) 1.6 hydrate {(CN)2B15C5}2 · 1.6H2O (IIa) and 4′,5′-dicyanobenzo-15-crown-5,4′-cyano-5′-cyano(bromo)benzo-15-crown-5 dihydrate (CN)3.85Br0.15(B15C5)2 · 2H2O (III) is performed. Crystals IIa are monoclinic, a = 15.882(2) Å, b = 11.412(2) Å, c = 18.484(3) Å, β = 100.717(3)°, V = 3291.7(9) Å3, Z = 4, space group P21/c, R = 0.0746 for 4775 reflections with I > 2σ(I). Crystals III are monoclinic, a = 15.956(3) Å, b = 11.425(2) Å, c = 18.865(4) Å, β = 99.32(3)°, V = 3394(1) Å3, Z = 4, space group P21/c, R = 0.0692 for 2070 reflections with I > 2σ(I). Compounds IIa and III have similar structures with two crystallographically independent molecules in each (A and B in IIa; C and D in III). Four of the five O atoms of a macrocycle in molecules A and C form hydrogen bonds with the water molecules. The latter molecules lie above and below the cycle plane at a distance of ~2 Å from this plane. The A and C molecules have identical conformations (TTG TTG TTG TTG TTC) that differ from those of molecules B (TTG TGG STT SSG TTC) and D (TTC TSG STT SSG TTC).  相似文献   

12.
Two complexes [Zn(SALIMP)(CH3CO2)]2 (1) and [Cu(SALIMP)Cl] (2) are obtained by the reactions of zinc(II) and copper(II) salts with a tridentate Schiff base ligand 2-[[(2-pyridinylmethyl) imino]methyl]phenol (HSALIMP). Their structure is determined by single crystal X-ray diffraction. Data for complex 1: C30H28N4O6Zn2, CCDC number: 668213, M r = 671.3, monoclinic, C2/c, with a = 34.670(5) Å, b = 15.266(2) Å, c = 23.464(4) Å, β = 114.045(2)°, V = 11341(3) Å3, Z = 16, F(000) = 5504, GOOF(F 2) = 0.894, the final R = 0.0520 and wR = 0.1272 for 10515 observed reflections with I > 2σ(I); complex 2: C13H12N2OClCu, CCDC number: 668211, M r = 311.24, triclinic, P-1, with a = 7.4050(8) Å, b = 10.2369(11) Å, c = 16.2873(17) Å, α = 87.728(2)°, β = 87.818(2)°, γ = 78.279(2)°, V = 1207.4(2) Å3, Z = 4, F(000) = 632, GOOF(F 2) = 1.077, the final R = 0.0326 and wR = 0.0381 for 4209 observed reflections with I > 2σ(I).  相似文献   

13.
Two Mn(II) coordination polymers, {[Mn3 (Pfca)6(Phen)2] · 2DMF} n (I) and [Mn(Pfca)2(Phen)(H2O)] n (II) (HPfca = 4-fluorocinnamic acid, Phen = 1,10-phenanthroline), were synthesized and characterized by elemental analysis, IR spectroscopy, thermogravimetric analysis, and singlecrystal X-ray diffraction (CIF files CCDC nos. 967513 (I), 1542972 (II)). Complex I crystallizes in the triclinic crystal system, space group Pī with a = 11.0821(11), b = 12.2632(12), c = 15.0288(15) Å, α = 87.3760(10)°, β = 88.4610(10)°, γ = 81.2220(10)°, V = 2016.0(3) Å3, ρc = 1.369 g/cm3, M r = 1662.25, Z = 1, F(000) = 853, μ = 0.543 mm–1, the final R = 0.0592 and wR = 0.1681 for 15498 observed reflections with I > 2σ(I). Complex II is of monoclinic system, space group P21/c with a = 18.0539(19), b = 8.5806(9), c = 18.758(2) Å, β = 116.5700(10)°, V = 2599.0(5) Å3, ρc = 1.491 g/cm3, M r = 583.44, Z = 4, F(000) = 1196, μ = 0.567 mm–1, the final R = 0.0337 and wR = 0.0853 for 18139 observed reflections with I > 2σ(I). Complex I features linear Mn(II)-trinuclear units, which form 1D chain structure through F···F weak interactions, and complex II is 1D polymeric Mn(II)-chains. Antiferromagnetic coupling interactions exist within Mn(II)- carboxylate trinuclear in I (J =–0.40 cm–1) and Mn(II)-carboxylate chain in II (J =–0.45 cm–1).  相似文献   

14.
Gold oxide films obtained on the surface of polycrystalline gold foil upon oxidation by oxygen activated by a high-frequency discharge have been studied by X-ray photoelectron spectroscopy. High-frequency O2 activation affords oxide films more than 3–5 nm thick. As follows from Au4f spectra, the surface gold atoms are oxidized to the oxidation state +3. The O1s spectra have a composite shape and are decomposed into four components that characterize nonequivalent states of oxygen in the resulting oxide films. It is assumed that the two major oxygen states (E b(O1s) = 529.0 and 530.0 eV) correspond to the oxygen atoms in two-and three-dimensional gold oxide Au2O3, respectively. The oxygen states characterized by the higher binding energies (E b(O1s) = 531.8 and 535.2 eV) likely correspond to molecular oxygen in peroxide and superoxide groups, respectively.  相似文献   

15.
The reaction of Ag2O and 2-amino-6-methylpyridine (AMP) with nicotinic acid (HNA) and isonicotinic acid (HINA), respectively, afforded two silver(I) complexes, [Ag2(NA)2(AMP)2] n (I) and [Ag2(INA)2(AMP)2] n (II). Both complexes were characterized by elemental analyses and X-ray single-crystal diffraction. Complex I is a pyridine-3-carboxylate bridged polynuclear silver(I) complex, in which the Ag atom is in a tetrahedral geometry, while complex II is a pyridine-4-carboxylate bridged polynuclear silver(I) complex, in which the Ag atom is in a distorted T-shaped geometry. The crystal of I is monoclinic: space group P21/c, a = 8.079(2), b = 17.150(3), c = 8.912(2) Å, β = 98.106(2)°, V = 1222.5(5) Å3, Z = 4. The crystal of II is monoclinic: space group P21/c, a = 7.225(1), b = 12.049(1), c = 15.053(2) Å, β = 102.050(1)°, V = 1281.6(3) Å3, Z = 4.  相似文献   

16.
Oxepin and azepin are heterocyclic compounds with a seven-membered ring, which are present in the main skeleton of many anti-depressive drugs. Planar configuration instability due to the pseudo Jahn-Teller effect (PJTE) in oxepin, azepin and six their halogen substituted derivatives were investigated as an original PJTE study. Optimization and the following frequency calculations in these two series illuminated that all of these eight compounds were unstable in high-symmetry planar (with C 2v symmetry) configuration and their structures were puckered to lower C s symmetry stable geometry. Moreover, the vibronic coupling interaction between 1 A 1 ground and the first 1 B 1 excited states via (1 A 1 + 1 A 1 + 1 B 1) ? b 1 and (1 A 1 + 1 B 1 + 1 A 1 ) ? b 1 PJTE problems were the reasons for the symmetry breaking phenomenon and non-planarity of the seven-member ring in those series. Finally, numerical fitting of the adiabatic potential energy surface (APES) cross-sections along the b 1 puckering coordination was employed to estimate the vibronic coupling constants of PJTE problems for all the considered compounds.  相似文献   

17.
New hexanuclear complexes of lanthanum and neodymium iodides, [La6(H2O)23(OH)10]I8 · 8H2O (I) and [Nd6(H2O)23(OH)10]I8 · 8H2O (II), are synthesized and studied by X-ray diffraction analysis. The isostructural crystals of complexes I and II are orthorhombic: a = 13.197(4) Å, b = 15.152(3) Å, c = 15.302(4) Å and a = 13.060(4) Å, b = 14.967(5) Å, c = 15.098(4) Å, respectively; Z = 2, space group Pnnm. The lanthanum (neodymium) atoms coordinate the aqua and hydroxo ligands and enter the composition of the Ln6 -containing complex cations. The coordination polyhedron (ignoring the central oxygen atom) of each atom of the complexing agent is somewhat distorted square antiprism with the aqua and hydroxo ligands being in the vertices. Four bridging ligands link this atom of the complexing agent with the four adjacent atoms.  相似文献   

18.
Temperature dependences of the heat capacity of cobalt manganites NdM2 I CoMnO5 (MI = Li, Na, and K) are studied by means of dynamic calorimetry in the range of 298.15?673 K. It is found that λ-shaped effects are observed on the C p ° ~ f (T) curve of cobalt manganites, due probably to second order phase transitions. Based on the experimental data, equations for the temperature dependences of the heat capacity of cobalt manganite are derived with allowance for the temperatures of phase transitions. The values of thermodynamic functions Н°(T)–Н°(298.15), S°(T), and Фхх(T) are calculated.  相似文献   

19.
A sample of magnesio-ferri-hornblendite, a potential new mineral of the amphibole supergroup, was studied by X-ray diffraction and IR spectroscopy. The crystal chemical formula is (Z = 2): AK0.04M(4) (Ca1.92Na0.08) C[M(1)(Mg1.78Fe0.224+) M(2)(Mg1.62Fe0.263+Al0.12) M(3)(Mg0.64Fe0.322+Mn0.04)] [T(Si7.44Al0.56)O22] W(OH)2. The monoclinic unit cell parameters are a = 9.855(1) Å, b = 18.084(1) Å, c = 5.289(1) Å, β = 104.853(2)°; V = 911.1(2) Å3; space group C2/m; Z = 2. The crystal structure was refined to R = 2.82% in the anisotropic approximation for atomic displacement parameters using 1166 reflections with I > 2σ(I). The magnesio-ferri-hornblendite structure is generally similar to the structures of other monoclinic calcium amphiboles, and its key distinctive features are the predominance of Мg among C2+ cations and Fe3+ among C3+ cations.  相似文献   

20.
The phenolic azide bridged dinuclear nickel(II) complex, [Ni2(L1)2(N3)(H2O)(μ1,1-N3)] · EtOH (I), and the thiocyanate bridged dinuclear copper(II) complex, [Cu2(L2)21,1-NCS)2] (II), where L1 and L2 are the deprotonated forms of 2-mothoxy-6-[(2-piperidin-1-ylethylimino)methyl]phenol and 2,4-dichloro-6-[(2-methylaminoethylimino)methyl]phenol, respectively, were synthesized and characterized by elemental analysis, IR spectra, and single-crystal X-ray diffraction. The crystal of I is orthorhombic: space group Pbca, a = 12.172(1), b = 20.953(1), c = 29.779(2) Å, V = 7594.8(9) Å3, Z = 8. The crystal of II is monoclinic: space group P21/n, a = 8.7615(11), b = 19.672(2), c = 16.568(2) Å, β = 99.449(2)°, V = 2816.9(6) Å3, Z = 4. The Ni atoms in I are in octahedral coordinations, and the Cu atoms in II are in square-pyramidal coordinations.  相似文献   

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