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791.
792.
《Fluid Phase Equilibria》2005,238(1):65-71
Consistent vapor–liquid equilibrium (VLE) data at 101.3 kPa have been determined for the ternary system isobutyl alcohol (IBA) + isobutyl acetate (IBAc) + butyl propionate (BUP) and two constituent binary systems: IBA + BUP and IBAc + BUP. The IBA + BUP system show lightly positive deviation from Raoult's law and IBAc + BUP system exhibits no deviation from ideal behaviour. The activity coefficients of the solutions were correlated with its composition by the Wilson, NRTL, UNIQUAC models. The ternary system is very well predicted from binary interaction parameters. BUP eliminates the IBA–IBAc binary azeotrope. The change of phase equilibria behaviour is significant therefore this solvent seems to be an effective agent for that azeotrope mixture separation. In fact, the mean relative volatility on a solvent free basis is 1.8.The binary VLE data measured in the present study passed the thermodynamic consistency test of Fredenslund et al. [A. Fredenslund, J. Gmehling, P. Rasmussen, Vapor–Liquid Equilibria Using UNIFAC, A Group Contribution Method, Elsevier, Amsterdam, 1977], and were correlated by the Wilson, NRTL and UNIQUAC models to relate activity coefficients with mole fractions. The VLE data obtained for the ternary system passed both the Wisniak L–W [J. Wisniak, Ind. Eng. Chem. Res. 32 (1993) 1531–1533] and McDermott–Ellis [C. McDermott, S.R. Ellis, Chem. Eng. Sci. 20 (1965) 293–296] consistency test. The parameters obtained from binary data were utilized directly to predict the phase behaviour of the ternary system. The results showed an excellent agreement with experimental values. 相似文献
793.
Two novel supramolecular complexes [Ni(cyclen)(H2O)2](tpa)(1) and [Cu(cyclen)H2O](tpa)⋅3H2O (2) were synthesized and their structures were characterized with elemental analysis, IR spectrum, TGA and X-ray diffractometer, indicating that the complexes 1 and 2 consist of one-dimensional chain and two-dimensional net-work structures formed by intermolecular hydrogen-bonding interaction, respectively. TGA curves show the similar steps of weightloss for 1 and 2. 相似文献
794.
795.
Based on the monodisperse poly(glycidyl methacrylate-co-ethylenedimethacrylate) beads (PGMA/EDMA) with macropore as a medium, a new hydrophilic medium cation exchange (MCX) stationary phase for HPLC was synthesized by a new chemically modified method. The stationary phase was evaluated with the property of ion exchange, separability, reproducibility, hydrophilicity, effect of salt concentration, salt types, column loading and pH on the separation and retention of proteins in detail. It was found that it follows ion exchange chromatographic (IEC) retention mechanism. The measured bioactivity recovery for lysozyme was (96 ± 5)%. The dynamic protein loading capacity of the synthesized MCX packings was 21.8 mg/g. Five proteins were almost completely separated within 6.0 min at a flow rate of 4 mL/min using the synthesized MCX resin. The MCX resin was also used for the rapid separation and purification of lysozyme from egg white with only one step. The purity and specific bioactivity of the purified lysozyme was found more than 95% and 70345 U/mg, respectively. 相似文献
796.
D. P. Krut’ko M. V. Borzov Long Yu Liao Wan Li Nie A. V. Churakov J. A. K. Howard D. A. Lemenovskii 《Russian Chemical Bulletin》2006,55(9):1574-1580
The new side-chain functionalized cyclopentadienyl ligand LiC5H4CPh2CH2R (R is 1-methylimidazol-2-yl) as lithium salt 2, the trimethylsilyl derivative Me3SiC5H4CPh2CH2R (3), and the ligand in the CH form (4) were prepared starting from 6,6-diphenylfulvene and 1,2-dimethylimidazole lithiated at the 2-Me group (1) and then characterized. The half-sandwich complexes (η5:η 1-C5H4CPh2CH2R)TiCl3 (5) and (η5:η 1-C5H4CPh2CH2R)ZrCl3 (6) were synthesized. The molecular structure of complex 5 was established by X-ray diffraction. Complexes 5 and 6 exhibit dynamic behavior in solution associated with degenerate interconversion of the pseudo-six-membered metallacycle.
For titanium complex 5 in a solvating solvent, a dynamic process due to intramolecular dissociation—coordination of the imidazole fragment was observed.
Published in Russian in Izvestiya Akademii Nauk. Seriya Khimicheskaya, No. 9, pp. 1518–1524, September, 2006. 相似文献
797.
Hydrothermal synthesis and X-ray characterized 3D supramolecular networks were constructed by [Co(HnicO)2·(H2O)2] (HnicOH=2-hydroxynicofinic acid) (1) as building block via abundant dimeric homomeric (N--H…O) and unusually cyclic tetrameric heteromeric (O-H…O) hydrogen-bonds. It is noted that there exist unusually linear metal-water chains comprised of tetrameric units linked by vertexes sharing cobalt centers through hydrogen-bonding. TG-DTG curves illustrated that thermal decomposition was completed by two steps, one is the loss of two terminal water molecules in the range of 156--234℃, and the other is the pyrolysis of HnicO ligand in the range of 234--730 ℃. The standard molar enthalpy of formation of the complex was determined to be (-1845.43± 2.77) kJ·mol^-1 by a rotary-bomb combustion calorimeter. 相似文献
798.
Introduction The chemistry of the sandwich-type heteropoly-oxometalates encapsulating clusters of early transition metals is current of considerable interest with respect to the application of complexes in material science, medi-cine, catalysis and fundamental perspectives.1-4 The great advantage of these complexes is the possibility of varying either the type of the metallic cluster or the het-eroatom. The proximity of the transition metals pos-sessing unpaired electrons facilitates their cou… 相似文献
799.
Two new nitronyl nitroxides with amido units L1 and L2 were synthesized and characterized. Reactions of L1 and L2 with M(hfac)2 [hfac=hexafluoroacetylacetonate, M=Co(II), Ni(II), Mn(II)] afforded five hetero-spin complexes LiCo(hfac)2, LlNi(hfac)2, L2Co(hfac)2, L2Ni(hfac)2 and L2Mn(hfac)2. The crystal structures and magnetic characterizations of L1, L2 and their metal complexes LM(hfac)2 were described and discussed. Crystal structural analysis shows that both the carbonyl oxygen and the nitroxide oxygen are coordinated to the metal ions. Strong antiferromagetic coupling between the nitronyl nitroxides and metal ions were observed for all the five LM(hfac)2 complexes. 相似文献
800.
水杨醛-1H-苯并三唑-1-乙酰腙与镧(Ⅲ)配合物的制备、表征及热化学 总被引:6,自引:0,他引:6
在甲醇中,利用水杨醛-1H-苯并三唑-1-乙酰腙(C15H13N5O2,简称SBTH)与高氯酸镧反应,制得一新配合物,经元素分析、化学分析并结合热分析确定了其组成为La(C15H12N5O2)( C15H11N5O2)•2.5H2O.利用电导测定、红外光谱、1H NMR和TG-DTG等手段推测了配合物的结构.用微热量计测定了配合物在不同浓度(b)时的溶解焓,用计算机拟合求得该配合物的标准摩尔溶解焓(ΔsolHmΘ=-135.62 kJ•mol-1)及溶解焓(ΔsolH)的经验公式(ΔsolH=-135.62-11633b+3761.5b1/2),并由此分别推导出配合物的相对表观摩尔焓(Li)、相对偏摩尔焓(Li)以及配合物稀释焓(ΔdilH1,2)的经验公式:Li=-11633b+3761.5b1/2;Li=-23266b+5642.2b1/2和ΔdilH1,2=-11633(b21/2-b11/2)+3761.5(b2-b1).还研究了配合物的热分解过程,利用Kissinger公式计算了配合物主要分解阶段的表观活化能(Ea=470.24 kJ•mol-1). 相似文献