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1.
The nuclear magnetic resonance spectra of the systems isopropanol/n-hexane and isopropanol/n-heptane are recorded to deduce thermodynamic functions. A discussion ofSaroléa-Mathot's methods follows.Für die im Titel genannten Systeme werden aus den NMR-Spektren thermodynamische Funktionen abgeleitet. Eine Diskussion derSaroléa-Mathot-Methode wird präsentiert.
Zur Thermodynamik des Isopropanol/n-Hexan und Isopropanol/n-Heptan Systems, II. NMR-Untersuchungen
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2.
Vapour pressure measurements are carried out at different temperatures; the activity coefficients are calculated and compared with those devived from IR and NMR data (parts I and II).
Zur Thermodynamik des Isopropanol/n-Hexan und Isopropanol/n-Heptan Systems, III. Gas-Flüssig-Gleichgewichte
Zusammenfassung Es wurden Dampfdruckmessungen bei verschiedenen Temperaturen ausgeführt. Die daraus bestimmten Aktivitätskoeffizienten wurden mit den aus IR- und NMR-Daten berechneten (siehe Mitt. I und II) verglichen.
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3.
Heats of mixing (H E)ofn-octane with 1,2,3,4-isomers ofn-octyne,n-heptane withn-1-heptyne andn-nonane withn-1-nonyne at temperatures from 298.15 to 318.15 K were measured with aCalvet-type microcalorimeter. The results are presented in tables and correlated with theRedlich-Kister equation.
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4.
The vapour-liquid equilibrium data obtained from isobarict-x-measurements have been used for calculation of the group UNIFAC parameters and excess free enthalpyG E of binary mixturesn-alkanes with isomericn-alkynes. The UNIFAC model gives satisfactory predictions for the systems studied. The temperature dependence ofG E was estimated on the basis of the heats of mixing measured earlier. The influence of the position of triple bond in the molecules ofn-alkynes on the excess thermodynamic functions is considered.
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5.
Liquid-liquid equilibria of the ternary system 1,2-dichloroethane/n-propanol/water were measured at 20, 30, and 40 °C. In the plot of the system for 20 °C are shown the results of titration (i. e. addition of increasing quantities of water resp. 1,2-dichloroethane to the homogenous mixture of the other components). These results geree well with the plot of extraction results.The binary homogeneous systemsn-propanol/water andn-propanol/1,2-dichloroethane exhibit an non-ideal behaviour. Vapor-liquid equil. of these systems were measures at 133.32 and 666.6 mbar (100 and 500 Torr). The azeotropic points at these pressures are in good agreement with the literature.In addition to this, measurements of the values of surface-tension, viscosity and refractive index were performed.Aqueous solutions ofn-propanol can be determined by the micromethod ofR. Fischer.
Unserem Lehrer, Herrn Universitätsprofessor Dr. et Mr.Robert Fischer zum 75. Geburtstag in Dankbarkeit und Verehrung gewidmet.Die Programme wurden auf der Rechenanlage UNIVAC 494 des Forschungszentrums Graz erstellt.  相似文献   

6.
Summary 1-(Tributylstannyl)hexanol ((±)-8 is phosphorylated to give phosphate (±)-9 which is then transmetallated. The organolithium intermediate (±)-10 isomerizes to -hydroxyphosphonate (±)-12. Similar intermediates are also formed upon direct deprotonation of triethyl, tri-n-propyl, and tri-n-butyl phosphate, which subsequently rearrange to -hydroxyphosphonates (±)-14a–c.
Die Phosphat-Phosphonat- und Phosphonat-Phosphat-Umlagerung und ihre Anwendungen, 5. Mitt. Über die Reaktion vons-Butyllithium/TMEDA mit symmetrischen Trialkylphosphaten
Zusammenfassung 1-(Tributylstanny)hexanol ((±)-8) wird phosphoryliert und liefert Phosphat (±)-9, das transmetalliert wird. Das lithiumorganische Zwischenprodukt (±)-10 isomerisiert zum -Hydroxyphosphonat (±)-12. Ähnliche Intermediate werden auch bei der direkten Deprotonierung von Triethyl-, Tri-n-propyl- und Tri-n-butylphosphat gebildet, die anschließend zu den -Hydroxy-phosphonaten (±)-14a–c umlagern.
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7.
Zusammenfassung Das Kompressionsverhalten folgender binärer Systeme wurde beiT=298 K auf 0,01 M HCl mittels Filmwaage untersucht: Stearinsäure/n-Dekan,n-Docosan,n-Octacosan Myristinsäure/n-Dekan,n-Docosan,n-Octacosan. Die Analyse derF/A-Isothermen der gespreiteten Mischungen ergibt, daß bei sämtlichen 6 Systemen der Filmtyp der Mischungen vom Filmtyp der Fettsäuren bestimmt wird. Die festgestellten Flächenaufweitungen sind erklärbar durch die Anwesenheit der Kohlenwasserstoffe in der Monoschicht und durch Linsen aus reinen Kohlenwasserstoffen, die durch Entmischungsvorgänge gebildet wurden.
The compression behaviour of the following systems was studied by use of a film balance atT=298 K on 0,01 M HCl substrate: stearic acid/n-decane,n-docosane,n-octacosane, myristic acid/n-decane,n-docosane,n-octacosane. From the analysis of theF/A-Isotherms of spread mixtures follows, that in all of the six systems the fatty acid determins the film type of mixtures. Area expansion of the fatty acid monolayers are thought to be due to the presence of the hydrocarbons within the monolayers and to the hydrocarbon lenses formed by demixing processes.
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8.
邓少君  郑欧  刘金彦  赵剑曦 《化学学报》2007,65(13):1212-1216
以FT-IR方法研究了水/C12-EOx-C12•2Br/正己醇/正庚烷形成的W/O微乳中水的状态. 结果表明, 其中的水存在4种状态, 分别为阳离子头基结合水、反离子结合水、类似本体的水以及束缚在微乳栅栏层中的水. 由解卷积技术分解FT-IR谱图, 进而获得每个表面活性剂分子对应于这4种状态水分子的数目nN+, nBr-, nbnf. 随着水含量(W0)增加, nb急剧增大, nN+少许上升, 而nfnBr-维持不变, 这说明微乳水核逐渐长大, 且在所考察W0范围内, 表面活性剂头基解离度保持不变.  相似文献   

9.
Infrared andRaman vibrational spectra ofn-Si4Cl10,n-Si5Cl12,neo-Si5Cl12 and [(SiCl3)3Si]2 have been measured and assigned. A local symmetry force field has been developed to simulate vibrational spectra of all (noncyclic) perchlorosilanes Si n Cl2n+2 known today (n=2, 3, 4, 5, 8). The observed spectra are reproduced satisfactorily
Die Vibrationsspektren linearer und verzweigter PerchlorsilaneSi n Cl 2n+2 und deren Simulierung mittels eines lokalen Symmetrie-Kraftfeldes
Zusammenfassung Infrarot- undRaman-Spektren vonn-Si4Cl10,n-Si5Cl12,neo-Si5Cl12 und [(SiCl3)3Si]2 wurden aufgenommen und zugeordnet. Ein lokales Symmetrie-Kraftfeld zur Simulation der Spektren aller bisher bekannten (nicht cyclischen) Perchlorsilane Si n Cl2n+2 (n=2, 3, 4, 5, 8) wird angegeben. Die beobachteten Spektren werden zufriedenstellend reproduziert
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10.
Poly(vinyl alcohol) (PVA) was blended with soluble polyelectrolyte complex (PEC) made from poly(diallyldimethylammonium chloride) (PDDA) and sodium carboxymethyl cellulose (CMCNa). Crystallinity, thermal transition, and thermal stability of the PVA/PEC blends were characterized by using wide angle X-ray diffraction (WAXD), differential scanning calorimetry (DSC), and thermal gravity analysis (TGA), respectively. Surface morphology, cross-section and phase structure of the blend membranes were examined by field emission scanning electron microscopy (FESEM) and atomic force microscopy (AFM). Surface hydrophilicity and swelling behavior of the blend membranes were examined by water contact angle (CA) and swelling tests. Blend membranes were subjected to isopropanol dehydration, and effects of blend composition, feed composition and feed temperature on pervaporation performance are discussed in terms of phase structures of blend membranes. A performance of J = 1.35 kg/m2 h, α = 1002, was obtained for blend membrane containing 50 wt% PEC in dehydrating 10 wt% water–isopropanol at 70 °C.  相似文献   

11.
Reaction of (RNPF3)2 compounds (R=CH3, C2H5,n-C3H7,n-C4H9,i-C4H9) withN-trimethylsilyl-methylamine leads to nucleophilic substitution of one or two fluorine atoms by the methylamino group, depending on the molar amounts of the reactants. In the case ofR=CH3, two by-products are formed: in the first step a compound with coordination numbers IV, V and VI for the three phosphorus atoms in C5H17F7N5P3 and in the second step a monospiroflourodiaza-5, 5-diphosphetidine.
9. Mitteilung:Utvary, K., Kubjacek, M., Varmuza, K. Z. anorg. allg. Chem.458, 281 (1979).  相似文献   

12.
The reaction of trimethylsilylcarbonamides with halogeno-diorganyl-boranes resp. trihalogenoboranes or organodihalogenoboranes gives monomeric resp. dimeric amidoboranes (borylcarbonamides) and derivatives of 4,8-diaza-1,5-dibora-2,6,9-trioxabicyclo[3.3.1]nonadienes. By reaction of the free acylamides with halogenoboranes in most cases the imide halides could be isolated as the only products. By reaction of the hydrochloride of bis(dimethylamino)-hydroxyborane withn-butyl-lithium followed by addition of the imide halides, the corresponding imidoylamines were formed.1H,11B, and19F-nmr spectra, mass spectra and characteristic ir group frequencies are reported.
15. Mitt.:W. Maringgele undA. Meller, Z. anorg. allg. Chem., im Druck.  相似文献   

13.
The reaction of fluorenone ethyleneketal (9), diphenic anhydride as well as of biphenyls such as4 with Cr(CO)6 in refluxing di-n-butylether (BE) gives dimethylbenchrotrenes [xylene-Cr(CO)3,7] which are also formed by refluxing pureBE with Cr(CO)6—although with much lower yields. Similarily, from di-n-pentylether and Cr(CO)6 isobutyl- and 1-methyl-3-propyl-benchrotrene (13 and14) were obtained, whilst from di-n-propyl- and-hexylether, resp., and Cr(CO)6 no benchrotrenes could be isolated.Tentative assumptions on the catalytic action of certain functional groups were confirmed by the reaction ofBE and Cr(CO)6 in the presence of carbonamides, such as acetamide, urea and pyrrolidone, where 1,4-dimethylbenchrotrene (7 c) was formed with appreciable yields.Studies using dideuteratedBE showed that—at least for the reaction of9 with Cr(CO)6 (giving a much lower yield of7 than with undeuteratedBE)—a simple bimolecular mechanism can be excluded.
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14.
[m . 2]Metacyclophanes with an oxo-function in the C2 bridge exhibit an enhanced carbonyl reactivity towards nucleophiles. The equilibrium constants for hydration and hemiacetal formation markedly decrease asm increases and qualitatively correlate with the ring strain present in the parent hydrocarbon. [m . n]Metacyclophanes withm,n 3 are almost free from intraanular steric strain. Accordingly, oxo-functions in the bridges do not exhibit an appreciable enhancement of reactivity.
Hydrat- und Hemiacetalbildung bei Oxo-[m . n]metacyclophanen
Zusammenfassung [m . 2]Metacyclophane mit einer Oxo-Funktion in der C2-Brücke zeigen eine erhöhte Carbonylreaktivität gegenüber Nucleophilen. Die Gleichgewichtskonstanten für die Hydratisierung und Hemiacetalbildung nehmen mit steigendemm ab und korrelieren qualitativ mit der Ringspannung des entsprechenden Kohlenwasserstoffs. Dagegen sind [m . n]Metacyclophane mitm,n 3 weitgehend frei von intraanularen sterischen Spannungen. Oxo-Funktionen in den Brücken besitzen deshalb keine nennenswert erhöhte Carbonylreaktivität.
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15.
The vibrational spectra of C6D5PX 2, (C6D5)2PX (X=H, Cl), (C6D5)3P and of the Cyclophosphanes (PC6H5) n and (PC6D5) n (n=5, 6) are reported. The spectra of the phenylphosphorouscompound D (the structure beeing unknown) are given too. The C6H5/C6D5 isotopic shift data in the lower frequency-region (600–100 cm–1) (facilitating the recognition of vibrational coupling effects) are used for vibrational assignments.
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16.
The statistical thermodynamics of adsorption from multicomponent liquid mixtures on heterogeneous solid surfaces is discussed by assuming the cell adsorption model and ideal adsorbed phase.Two integral representations for the adsorption isotherm are proposed: one based onn-dimensional energy distribution function (i.e., each adsorption site is characterized by adsorption energies of all components), and the other based on distribution of differences of adsorption energies ofn-1 components in relation to adsorption energy of the chosen component (i.e., each adsorption site is characterized byn-1 differences of adsorption energies of the components in relation to adsorption energy of the chosen component).The expressions for differential adsorption heat for adsorption from binary liquid mixtures have been derived from both integral equations.
Statistische Thermodynamik der Adsorption aus flüssigen Mehrkomponentenmischungen auf heterogenen festen Oberflächen
Zusammenfassung Die statistische Thermodynamik der Adsorption von aus mehreren Komponenten bestehenden flüssigen Mischungen auf heterogenen festen Oberflächen wird für das Modell der Zellenadsorption bei ideal adsorbierter Phase diskutiert.Zwei Integraldarstellungen der Adsorptionsisotherme werden vorgeschlagen: eine auf einen-dimensionale Verteilungsfunktion der Energie gestützte (das heißt, jede Adsorptionsstelle wird durch Adsorptionsenergien von allen Komponenten charakterisiert); die andere basiert auf der Verteilung der Unterschiede von Adsorptionsenergien dern-1-Komponenten in bezug auf die Adsorptionsenergie der ausgewählten Komponente (das heißt, jede Adsorptionsstelle wird durchn-1-Unterschiede charakterisiert. Formeln für differentiale Adsorptionswärmen für die Adsorption aus binären flüssigen Mischungen sind von beiden Integral-Gleichungen abgeleitet worden.
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17.
A number of polynuclear mixed carboxylates of nickel(II) with the general composition [Ni(OOCCH3)2–n (OOCR) n ] x (whereR=C13H27, C15H31, C17H35 and C21H43 andn=1 or 2) have been synthesized by the transacylation reactions of anhydrous nickel acetate with higher carboxylic acids in refluxing toluene. On recrystallization from benzene-alcohol mixtures, mono-alcoholate complexes, Ni(OOCCH3)2–n (OOCR) n ·ROH (whereR=CH3 and C2H5) have been isolated. All these derivatives have been characterized by the molecular weight determinations, infra-red and electronic reflectance spectra and magnetic susceptibility measurements.
Synthese und Eigenschaften einiger gemischter Carboxylat-Komplexe von Nickel(II)
Zusammenfassung Komplexe des Typs [Ni(OOCCH3)2–n (OOCR) n ] x (mitR=C13H27, C15H31, C17H35 und C21H43,n=1 oder 2) wurden aus wasserfreiem Nickelacetat mit höheren Carbonsäuren in siedendem Toluol erhalten. Bei der Kristallisation aus Benzol-Alkohol-Mischungen wurden Monoalkoholate Ni(OOCCH3)2–n (OOCR) n ·ROH (mitR=CH3 und C2H5) isoliert. Die Charakterisierung der Komplexe erfolgte mittels Molekulargewichtsbestimmung, Infrarot- und Elektronenspektren und der Messung der magnetischen Susceptibilität.
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18.
Polyelectrolyte complexes (PECs) of sodium carboxymethyl cellulose (CMCNa) and poly(diallyldimethylammonium chloride) (PDDA) were prepared in dilute hydrochloric acid (HCl) aqueous solution and obtained in its solid form. Element analysis and FT-IR showed that the composition of PECs could effectively be tuned by the concentration of HCl in parent polyelectrolyte solution. The PECs were then dissolved in 0.1 mol/L aqueous NaOH and subsequently cast onto polysulfone ultra-filtration membrane. This composite membrane, which has a unique homogeneous PECs separation layer, was subjected to pervaporation test for the first time and gave a performance of J = 3.0 kg/m2 h, α = 960 for 10 wt% water–isopropanol feed at 75 °C. Meanwhile, performance of the PECs membrane displays good stability and unique dependence on feed temperature. These findings, together with its ultra-high performance, are primarily explained by the structure characteristic of PECs.  相似文献   

19.
Ion/molecule reactions of four coordinateSchiff base complexes under negative ion chemical ionization conditions have been studied. The complex metal ions consisted of cobalt(II), nickel(II) and copper(II).Schiff base ligands with different donor strengths were employed. The gas mixtures used contained 90% methane and 10% of the gases O2, NO or CO. The spectra showed intense molecular negative ions, formed by secondary electron capture processes. Secondary ions were formed via ion/molecule reactions between the parent molecular negative ion and added gas molecules to giveMLX ,X=O2, NO, CO;L=Schiff base ligand,M=Co(II) or Ni(II). Consistent with former investigations, secondary ion formation was not found for the copper compounds. Influence of the central metal ion as well as the ligand donor strength on the ion/molecule reactions are discussed. From the results obtained a mechanism of the secondary ion formation is suggested.
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20.
The title complexes are used as intramolecular cyclization agents to yield under mild conditions and average to good yields 2-azetidinones from variously substituted 3-aminopropanoic acids. The reaction is found to proceed in all examined cases stereospecifically, with one exception. No marked difference with respect to yields and stereospecificity is noted among the four condensation systems.
2-Azetidinone aus 3-Aminopropansäuren und Ph3 P/CCl 4(CBr 4) oder Ph3 P/Br 2(I 2) als Kondensationsmittel
Zusammenfassung Die im Titel angegebenen Systeme wurden als Cyclisationsreagentien eingesetzt, um aus substituierten 3-Aminopropansäuren 2-Azetidinone unter milden Bedingungen und mit durchschnittlichen bis guten Ausbeuten darzustellen. Mit einer Ausnahme läuft die Reaktion stereospezifisch. Bei den vier untersuchten Systemen wurde kein beträchtlicher Unterschied in bezug auf Ausbeute und Stereospezifität festgestellt.
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