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1.
《Fluid Phase Equilibria》1999,165(2):157-168
A simple method is developed to estimate mixture critical temperatures (Tc), pressures (Pc), and densities (ρc) as a function of overall composition (X) from near critical region experimental coexistence data. This three-step method is applied to four mixtures, CO2–C3H8, CO2nC4H10, C2H6–C3H8, and C3H8nC4H10. Isothermal liquid–vapor coexistence data, which includes temperature, vapor pressure, coexisting densities (ρ and ρv), and coexisting compositions for the more volatile component (x1v and x1) are used. In the first step, the difference of the saturated liquid and vapor densities (ρρv) is fitted to an empirical function in ((PcP)/Pc) to obtain Pc. Then P/Pc and ((ρ+ρv)/2ρc) are simultaneously fitted to functions of a polynomial in (X1−(x1v+x1)/2) yielding estimates of ρc and X1. Finally, the discrete estimated critical data points are fitted with an equation to provide a continuous representation of the critical lines. The method is successfully tested for the mixtures, CO2–C3H8 and CO2nC4H10, for which there is a reasonable amount of isothermal data. The procedure is then applied to the mixtures, C2H6–C3H8 and C3H8nC4H10, for which there are sparse data. For all four mixtures, the critical temperature line, Tc vs. X1, matches literature values within ±0.5%. The critical pressure line, Pc vs. X1, and critical density line, ρc vs. X1, match literature values, in general, within ±2%.  相似文献   

2.
The title compound (C4N2H12)2Zr(C2O4)4·H2O 1 was synthesized by the reaction of ZrOCl2·8H2O, H2C2O4·2H2O and piperazinium in aqueous solution. Single-crystal X-ray analysis has revealed that compound 1 (C16H26N4O17Zr, Mr = 637.63) crystallizes in the monoclinic system, space group P21/c with a = 9.0425(3), b = 13.3844(3), c = 19.1191(5)A, β = 98.365(1)o, V = 2289.34(11) A3, Z = 4, Dc = 1.850 g/cm3, F(000) = 1304, μ = 0.577 mm-1, the final R = 0.0240 and wR = 0.0628 for 4386 observed reflections with I > 2σ(I). X-ray crystal-structure analysis suggests that compound 1 consists of [Zr(C2O4)4]4- anion and two protonated piperazinium cations. The anions are linked through hydrogen bonds of piperazinium. FT-IR and Raman spectra clearly show the existence of oxalate groups in the crystal lattice.  相似文献   

3.
《Solid State Sciences》2001,3(5):623-632
Zr(PO4)2·N2C2H10 or MIL-43 and Ti2(PO4)2(HPO4)2·N2C2H10 or MIL-44 were prepared hydrothermally (20 or 4 days, 473 or 453 K, respectively, autogenous pressure) in the presence of ethylenediamine. Their structures have been determined by single-crystal X-ray diffraction. MIL-43 crystallises in the monoclinic space group P21 (No. 4) with a=11.0722(1), b=10.6631(1), c=16.4642(2) Å, β=95.991(1)° and V=1933.21(3) Å3 (final agreement factors R1(F)=0.0466, wR2(F2)=0.1096). Due to the very poor quality of the crystal, only an approached structure of MIL-44 is given; it crystallises in the triclinic space group P1 (No. 1) with a=5.0845(4), b=6.3097(5), c=12.6111(9) Å, α=77.454(1), β=78.926(2), γ=89.986(1)° and V=387.21(5) Å3. Both solids are two-dimensional and are the ion-exchanged equivalents of the layered solids αZrP and γTiP. Inorganic sheets of MIL-43 are built up from pseudo-hexagonal arrays of ZrO6 octahedra surrounded by PO4 tetrahedra pointing their terminal oxygen alternatively up and down at the interlayer space. Layers of MIL-44 are made of double (TiOP) chains built from TiO6 octahedra and PO4 tetrahedra on which HPO4 groups are grafted pointing towards the interlayer space. In both cases, diprotonated organic templates, located between the layers, interact with terminal phosphate groups and ensure via hydrogen bonds the stability of the structures.  相似文献   

4.
The mechanism and kinetics of energy transfer from Xe(6s[3/2]1) resonance state (E=8.44 eV) to selected hydrocarbon molecules have been investigated by XeCl(B–X) (λmax=308 nm) fluorescence intensity measurements at stationary conditions in Xe–CCl4–M systems. Steady-state analysis of the fluorescence intensity dependence on the xenon and M pressure at constant CCl4 concentration shows that these process occur in the two- and three-body reactions: Xe(6s[3/2]10)+M→products, Xe(6s[3/2]10+M+Xe→products. The two- and three-body rate constants for these reactions have been found (see Table 1Table 1. Experimental parameters of Eq. (8)found by least square method in Xe–CCl4–C2H2 and Xe–CCl4–C2H4 systems for chosen xenon pressures in the range 25–150 Torr. Linear correlation coefficients (R) are also shown  相似文献   

5.
Two Cu(II) hydroxo succinates [Cu3(H2O)2(OH)2(C4H4O4)2]?·?4H2O (1) and [Cu4(H2O)2(OH)4(C4H4O4)2]?·?5H2O (2) and one Cu(II) hydroxo glutarate [Cu5(OH)6(C5H6O4)2]?·?4H2O (3) have been prepared and structurally characterized by single crystal X-ray diffraction methods. They feature 1D and 2D copper oxygen connectivity of elongated {CuO6} octahedra in “4?+?1?+?1” and “4?+?2” coordination geometries. Within 1, linear trimers of three edge-sharing {CuO6} octahedra are connected into copper oxygen chains, which are bridged by the anti conformational succinate anions to generate 2D layers with mono terminally coordinating gauche succinate anions on both sides. The layers are assembled into a 3D framework by interlayer hydrogen bonds with lattice H2O molecules distributed in channels. Different from 1, the principal building units in 2 are linear tetramers of four edge-sharing {CuO6} octahedra. The tetramers are condensed into copper oxygen chains and the succinate anions interlink them into a 3D framework with triangular channels filled by lattice H2O molecules. The {CuO6} octahedra in 3 are edge-shared to form unprecedented 2D inorganic layers with mono terminally coordinating glutarate anions on both sides. Interlayer hydrogen bonding interactions are responsible for supramolecular assembly of the layers into a 3D framework with lattice H2O molecules in the channels. The inorganic layers in 3 can be described as hexagonal close packing of oxygen atoms with the Cu atoms in the octahedral cavities. The title compounds were further characterized by elemental analyses, IR spectra and thermal analyses.  相似文献   

6.
7.
《Chemical physics letters》1985,122(4):361-364
Reaction rate constants of SiH2(X̄1A1) have been directly measured for the first time using the laser photolysis—laser-induced fluorescence method. The preparation of SiH2 radical in the laser photolysis (193 nm) of phenylsilane and the concentration of the radical is demonstrated by a dye laser at 580.1 nm (X̄1A11B1). The reaction rate constants of SiH2(X̄1A1) with H2, CH4, C2H4, SiH4 and Si2H6, are 0.001, 0.01, 0.97, 1.1 and 5.7×10−10 cm3 molecule−1 s−1, respectively. For SiH21B1(0.2,0)), the collision-free lifetime is 0.6 μs and the quenching rate constant for He is 3.8×10−10 cm3 molecule−1 s−1.  相似文献   

8.
Two new Cd(II) coordination polymers, [Cd(C4H6N2)2(C4H2O4)(H2O)2] n (1) (where C4H6N2?=?2-methylimidazole, C4H2O4?=?fumarate), and [Cd(C4H6N2)(H2O)(C4H4O4)] n ?·?nH2O (2), (where C4H4O4?=?succinates), have been prepared and structurally characterized by single crystal X-ray diffraction. Complex 1 crystallizes in the triclinic space group P 1 in a one-dimensional chain structure, in which carboxy is monodentate; a three-dimensional supermolecular network structure was formed through hydrogen bonding. In complex 2, the coordination geometry of the Cd atoms is a pentagonal bipyramid, and a two-dimensional sheet is formed though carboxyl group bridging. In 1 and 2, IR spectra indicate the presence of bridging carboxyl groups, confirmed by structure analyses.  相似文献   

9.
Triphenylguanidinium Ph3GH+ salts with the anions B10H 10 2? , B12H 12 2? , B9C2H 12 2? , [Co(C2B9H11)2]?, and [Ni(C2B9H11)2]? were synthesized and described by DTA, IR spectroscopy, and solid-state luminescence. By IR spectroscopy, it was shown that intermolecular interactions involving the NH groups of the cation are enhanced in the sequence [Co(C2B9H11)2]? ~ [Ni(C2B9H11)2]? < B9C2H 12 2? < B12H 12 2? < B10H 10 2? .  相似文献   

10.
Under hydrothermal conditions, two new ribbon-like structures, [Cu(C14H9O4)-analysis revealed that these structures were constructed by mixed ligands. The coordination polymer forms the basic architecture while the weak interactions extend the framework into a secondary structure. The whole structures of them are governed by collaboration of the strong and weak interactions. Compound 1 crystallizes in monoclinic, space group C2/c with a = 17.0485(3), b =1 1.0558(3), c = 22.7623(4) A, β = 102.465(1)°, V = 4189.2(2) A3, Z = 4, Mr = 915.44, Dc = 1.451g/mL, F(000) = 1900 andμ(MoKα) = 0.587 cm-1. The final R and wR are 0.0030 and 0.1022,respectively for 3037 observed reflections with I > 2σ(I). Compound 2 crystallizes in monoclinic,space group P21/c with a = 11.5963(4), b = 11.7004(5), c = 17.1254(5) A,β = 95.620(1)°, V =2312.4(1) A3, Z = 4, Mr = 556.35, Dc = 1.598 g/mL, F(000) = 1132 andμ(MoKα) = 0.912 cm-1The final R and wR are 0.0431 and 0.1050, respectively for 2629 observed reflections with I > 2σ(I).  相似文献   

11.
From hydrothermal treatment of benzene-1,2-diamine, pyrocatechol, and MoO3 in acetic acid solution, a new compound, [Mo22-O)2(C6H4O2)2(H2O)] · (C8H9N2)2 · 2H2O (I), constructed from pyrocatechol chelated dinuclear molybdenum units and 2-methylbenzimidazole has been synthesized. Single-crystal structure analysis reveals that the compound crystallizes in the monoclinic space group P21/c with a = 23.365(2), b = 7.2214(5), c = 19.3021(16) β = 97.929(4), V = 3225.6(5), Z = 4, M = 808.46, ρc = 1.665 g/cm3, μ(MoK α) = 0.84 mm?1, F(000) = 1608, the final R = 0.0622 and wR = 0.1484 for 7385 independent reflections with R int = 0.0393. Interestingly, an in situ condensation between acetic acid and benzene-1,2-diamine has occurred, and the unexpected 2-methyl-1-H-benzo[d] imidazoles serve as counterions and N-H donors to form stable hydrogen-bond network in the crystal. Furthermore, intermolecular hydrogen bonds are found among the cations, anions and crystalline water molecules. The double nuclear molybdenum units are connected by O-H...O hydrogen bonds with the crystalline water molecules to form one-dimensional chains, and the chains are further joined together by N-H...O to form a quasi-two dimensional structure.  相似文献   

12.
<正> INTRODUCTION. Since some derivatives of alkylating ferrocene were found to be effective catalysts for promoting combustion speed of high energy fuels, research works on ferrocene derivatives have been rapidly developed.  相似文献   

13.
The organoantimony peroxide (Ar2SbO)4(O2)2 (Ar = C6H3OMe-2, Br-5) was synthesized by the oxidation of Ar3Sb with hydrogen peroxide in the presence or acetoxime or acetophenone oxime in dioxane. The product crystallizes with various content of the solvent molecules in the crystal unit cell [1.5 (I) and 6 (II), respectively]. An X-ray diffraction analysis of the solvates was performed. Four antimony atoms in the peroxide are in the octahedral coordination, and are linked through bridging oxygen atoms and two peroxide groups. The distances Sb-C, Sb-Obridge, Sb-Operoxide, O-O and Sb...Sb are 2.117–2.122, 1.960–1.972, 2.193–2.235, 1.461, 1.465 and 3.223–3.237 Å in I, and 2.112, 2.119, 1.957, 1,966, 2.204, 2,246, 1,467, and 3.2439 Å in II.  相似文献   

14.
X-ray diffraction study of tetranuclear organobismuth complexes Bi4(O)2(O2CC6H2F3-3,4,5)8 · 26-C6H6 and Bi4(O)2(O2CC6H2F3-3,4,5)8 · 2(C6H4Me2-1,4) revealed four Bi atoms connected through the bridging carboxylate ligands and the O atoms. The coordination sphere of the terminal Bi atoms includes the chelate carboxylate ligand and the 6-arene molecule. The bridging O atoms are tricoordinated, the distances between the terminal Bi atom and the center of benzene molecule (1,4-dimethylbenzene) are 3.024 Å(3.131 Å).Translated from Koordinatsionnaya Khimiya, Vol. 31, No. 1, 2005, pp. 4–11.Original Russian Text Copyright © 2005 by Sharutin, Egorova, Sharutina, Ivanenko, Adonin, Starichenko, Pushilin, Gerasimenko.  相似文献   

15.

Reaction of a freshly prepared Ni(OH)2?2 x (CO3) x ·yH2O with maleic acid in H2O at room temperature afforded [Ni(H2O)6][Ni(H2O)2(C4H2O4)]·4H2O, which consists of [Ni(H2O)6]2+ cations, [Ni(H2O)2(C4H2O4)]2? anions and lattice H2O molecules. Ni atoms in cations are octahedrally coordinated and Ni atoms in anions are each octahedrally coordinated by bidentate chelating maleato ligands and two water molecules at trans positions. Cations and anions are interlinked by hydrogen bonds to form 1D chains, which are hexagonally arranged and connected by the lattice water molecules. When heated in a flowing argon stream, the compound decomposes, with complete dehydration being followed by dissociation of nickel maleate into NiO and maleic anhydride.  相似文献   

16.
Two new benzene clathrates of the form Cd(4,4-bipyridyl)M(CN)4 · 2C6H6, (M=Cd or Hg) have been prepared in powder form. Their spectral data were compared with those of the corresponding host complexes and found to be consistent with the host structure found in Td-type clathrates.  相似文献   

17.
The title compound (C6N3H18)2Ti4O4(C2O4)7(4H2O 1 (C13H22N3O18Ti2, Mr = 604.14) was synthesized by the reaction of Ti(SO4)2, H2C2O4(2H2O and N-(2-ammonioethyl)- piperazinium (AEPP) in aqueous solution. The single-crystal X-ray analysis has revealed that 1 crystallizes in the triclinic system, space group Pī with a = 9.1437(6), b = 11.4991(10), c = 11.6975(8)A, α = 96.2915(18), β = 107.998(3), γ = 104.276(4)°, V = 1110.35(14)A3, Z = 2, Dc = 1.807 g/cm3, F(000) = 618, μ = 0.815 mm-1, the final R = 0.0463 and wR = 0.1264 for 3718 observed reflections with I > 2σ(I). X-ray crystal-structure analysis suggests that compound 1 consists of [Ti4O4(C2O4)7]6- anion and two protonated N-(2-ammonioethyl)piperazinium cations. The anions are linked into an infinite chain through Ti4O4(C2O4)8 by sharing the oxalates as bridging ligands.  相似文献   

18.
The binuclear complexes [Cu2L2(H2O)4] · 5H2O (1) and [Ni2L2(H2O)4] · 2H2O (2) (where L = C11H11NO5S, H 2 L = 2-[(3-formyl-5-methyl-2-hydroxy-benzylidene)-amino]ethanesulfonic acid) have been synthesized and characterized by IR, elemental analysis and X-ray diffraction. The crystals belong to the monoclinic system, space group P21/c. Complex 1: a = 16.8902(12), b = 11.2829(6), c = 17.4249(11) Å; β = 106.709(4)°; S = 1.131; V = 3180.5(3) Å3; Z = 4; D Calcd = 1.729 g cm?3; F(000) = 1712; μ = 1.554 mm?1; R 1 = 0.0519, wR 2 = 0.1349; complex 2: a = 11.399(2), b = 19.985(3), c = 7.3694(10) Å; β = 108.664(7)°; S = 1.157; V = 1590.6(4) Å3; Z = 2; D Calcd = 1.604 g cm?3; F(000) = 800; μ = 1.388 mm?1; R 1 = 0.1859, wR 2 = 0.4346. The geometry around each metal(II) center can be described as slightly distorted octahedral. Water-sulfonic clusters and (H2O)4 water clusters can be observed for 1 from the crystal packing diagram, while cavity and offset face-to-face π–π stacking can be observed for 2. The complexes have been tested for the antibacterial activities which show antibacterial activities of 1 for β-hemolytic streptococcus, Staphylococcus aureus and Escherichia coli, and the antibacterial activity of 2 only for β-hemolytic streptococcus.  相似文献   

19.
20.
A complex of Lutetium perchloric acid coordinated with l-glutaminic acid (C5H9NO4) and imidazole (C3H4N2), Lu(C5H9NO4)(C3H4N2)6(ClO4)3·5HClO4·10H2O was synthesized and characterized. Thermodynamic properties of the complex were studied with an adiabatic calorimeter (AC) from 80 to 390 K and differential scanning calorimetry (DSC) from 100 to 300 K. Two thermal abnormalities were discovered at 220.34 and 248.47 K, which were deduced to be phase transitions. One was interpreted as a freezing-in phenomenon of the reorientational motion of ClO4 ? ions and the other was attributed to the orientational order/disorder process of ClO4 ? ions. The low-temperature molar heat capacities were measured by AC and the thermodynamic functions [H T  ? H 298.15] and [S T  ? S 298.15] were derived in the temperature range from 80 to 390 K with temperature interval of 5 K. Thermal decomposition behavior of the complex was studied by thermogravimetric analysis and DSC.  相似文献   

P(Xe) (Torr)C2H4C2H2
Empty Cellab×1016 cm3/molec.Rab×1016 cm3/molec.R
250.923.260.981.002.780.95
400.863.290.971.002.910.98
500.873.330.970.993.050.98
600.853.330.971.022.990.98
750.863.390.971.032.950.98
900.923.300.971.032.850.98
1000.923.210.981.02.770.98
1100.883.190.961.022.710.99
1250.863.120.95
1400.922.900.95
1500.952.770.94
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