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1.
Selected extraction systems of TcO 4 –(H,Na)A–H2O/R(TcO4,A)–CHCl3, C6H5NO2 type, where A=Cl, NO 3 , ClO 4 , R=(C6H5)4As+, were studied. The solvent extraction of sub- and super-stoichiometric ratio of TcR was performed. The solubility of (C6H5)4AsTcO4 in water, chloroform and nitrobenzene were determined too. The results of the extractions are presented in the form of TcO 4 distribution dependencies on the phase composition and the extraction constants of individual TcO 4 , Cl, NO 3 , ClO 4 anions and TcO 4 -Cl, TcO 4 –NO 3 , TcO 4 –ClO 4 ion pairs.  相似文献   

2.
The linear isopiestic relation has been used, together with the fundamental Butler equations, to establish a new simple predictive equation for the surface tensions of the mixed ionic solutions. This newly proposed equation can provide the surface tensions of multicomponent solutions using only the data of the corresponding binary subsystems of equal water activity. No binary interaction parameters are required. The predictive capability of the equation has been tested by comparing with the experimental data of the surface tensions for the systems HCl–LiCl–H2O, HCl–NaClO4–H2O, HCl–CaCl2–H2O, HCl–SrCl2–H2O, HCl–BaCl2–H2O, LiCl–NaCl–H2O, LiCl–KCl–H2O, NaCl–KCl–H2O, KNO3–NH4NO3–H2O, and LiCl–NaCl–KCl–H2O at 298.15 K; KNO3–NH4Cl–H2O, KBr–Sr(NO3)2–H2O, NaNO3–Sr(NO3)2–H2O, NaNO3 –(NH4)2SO4–H2O, KNO3–Sr(NO3)2– H2O, NH4Cl–Sr(NO3)2–H2O, NH4Cl– (NH4)2SO4–H2O, KBr–KCl–H2O, KBr–KCl–NH4Cl–H2O, KBr–KNO3– Sr(NO3)2–H2O, KBr–NH4Cl–Sr(NO3)2–H2O, KNO3–NH4Cl–Sr(NO3)2–H2O, and NH4Cl–(NH4)2SO4–NaNO3–H2O at 291.15 K; and KBr–NaBr–H2O at temperatures from 283.15 to 308.15 K. The agreement is generally quite good.  相似文献   

3.
Summary Deuteration technique was applied to study the micro structures of copolymer series VDC/VC by infrared spectroscopy and high resolution NMR. The CH2 bending modes of chlorine atom containing polymers assigned as follows; –CCl2CH2CCl2– 1405 cm–1 (cryst.) and 1410 cm–1 (amorph.), –CHClCH2CCl2– 1422 cm–1, –CHClCH2CHCl– 1428 cm–1 (cryst.) and 1432 cm–1 (amorph.) –CHClCH2CH2CHCl– 1445 cm–1 and –CCl2CH2CH2CCl2– 1448 cm–1. This infrared interpretation shows that only the head to tail addition occurs in the copolymerisation. Nine peaks of the methylene protons were observed clearly in the NMR spectra of the copolymers. The study of the deuterated copolymers revealed that the effects of the chemical groups until the third at both sides from the marked methylene and the stereo configuration of long VC part should be considered to assign the NMR spectra. The CCl2 group made the chemical shift of the methylene proton to appear at lower magnetic field and the CHCl group gave the opposite behavior.
Zusammenfassung Mit deuterierten Monomeren wurde die Mikrostruktur der Copolymerenserie Vinyliden-Chlorid/Vinyl-Chlorid im Infraroten und mit hochauflösender Kernresonanz untersucht. Für die Biegeschwingung der Chloratome enthaltenden Polymeren der Methylengruppe ergeben sich folgende Werte: –CCl2CH2CCl2– 1405 cm–1 (krist.) und 1410 cm–1 (amorph.), –CHClCH2CCl2– 1422 cm–1, –CHClCH2CHCl– 1428 cm–1 (krist.) und 1432 cm–1 (amorph.), –CHClCH2CH2CHCl– 1445 cm–1 und –CCl2CH2CH2CCl2– 1448 cm–1.Diese Interpretation des Infraroten zeigt, daß nur die Kopf-Schwanz-Addition bei der Copolymerisation stattfindet. Neun Maxima des Methylenprotons wurden deutlich in den NMR-Spektren der Copolymeren beobachtet. Die Untersuchungen an den deuterierten Copolymeren zeigen, daß die Effekte der chemischen Gruppen bis zur dritten nach beiden Seiten vom markierten Methylen und die Stereokonfiguration von langen Vinyl-Chlorid-Anteilen betrachtet werden müssen, um die NMR-Spektren zu beschreiben. Die CCl2-Gruppe läßt die chemische Verschiebung des Methylen-protons bei geringeren magnetischen Feldern und die CHCl-Gruppe bei höheren erscheinen.


With 5 figures in 13 details and 4 tables  相似文献   

4.
Enthalpies of some of the phases in the Y–Ba–Cu–O system were determined by solution calorimetry using a Calvet microcalorimeter. The standard enthalpies of formation for the phases were found to be YBa2Cu3O6.60, –2627.9; YBa2Cu3O6.77, –2641.8; YBa2Cu3O6.90, –2652.0; YBa2Cu3O6.99, –2659.3; Y2Cu2O5, –2198.6; Y2BaCuO5, –2656.4; BaCuO2.33, –788.6; and BaCuO2.42, –796.2 kJ-mol–1.  相似文献   

5.
Organoantimony peroxides (Ar2SbO)4(O2)2 (Ar = Ph, p-Tol) were synthesized by oxidation of triarylantimony with hydrogen peroxide in the presence of nitrosophenol or 4-chlorophenol in an ether solution. X-ray diffraction analysis of peroxides obtained revealed that four antimony atoms have octahedral coordination and are connected via bridging oxygen atoms and two peroxide groups. The C–Sb, Sb–Obr, Sb–OO, and O–O distances are equal to 2.106–2.127, 1.958–1.974, 2.202–2.246, 1.471, 1.470 Å (Ar = Ph) and 2.086–2.139, 1.932–1.983, 2.215–2.289, 1.445–1.466 Å (Ar = p-Tol).  相似文献   

6.
Apparent molar volumes and heat capacities of aqueous GaCl3 have been measured at 25°C in binary GaCl3 solutions up to 3 mol-kg–1, and in ternary GaCl3-HCl solutions, containing 0.1345 mol-kg–1 HCl to suppress hydrolysis, up to a concentration of 1 mol-kg–1 GaCl3. Using the Pitzer interaction model for the excess properties, and using ridge regression for the derivation of physically meaningful regression parameters, the measurements yield the following results for the standard molar properties and Pitzer parameters at 25°C: V0(GaCl3)=12.85 cm3-mol–1; 0 v (GaCl3)=1.10×10–4 kg-mol–1–J–1–cm–3; v 1 (GaCl3)=2.12×10–3 kg–mol–1–J–1–cm3; Cv(GaCl3)=1.34×10–5 kg2–J–1–cm3; Vo(GaOHCl2)=13.84 cm3–mol–1; C o p (GaCl3)=–480.8 J–K–1–mol–1; J 0 (GaCl3)=–8.02×10–6 kg–mol–1–K–2; J 1 (GaCl3)=0.73×10–4 kg–mol–1–K–2; CJ(GaCl3)=–2.52×10–6 kg2-mol–2-K–2; C p 0 (GaOHCl2)=20.4 J-K–1-mol–1. The latter parameter has only mathematical significance, its physical meaning is unclear. Comparison of the present experimental results for the standard molar properties of Ga3+ with semi-empirical correlations casts doubt upon the general validity of these correlation methods for trivalent cations.  相似文献   

7.
Oxygen was determined in three kinds of ZrF4-based fluoride glass [ZrF4–BaF2–GdF3–AlF3 (ZBGA), ZrF4–BaF2–LaF3–YF3–AlF3–LiF–NaF (ZBLYALN) and ZrF4–BaF2–LaF3–YF3–AlF3–LiF (ZBLYAL)] used for fabricating optical fiberby18O(p, n)18F reaction without significant nuclear interference. The main long life96Nb nuclide was produced by the96Zr(p,n) reaction in a non-destructive analysis of ZBGA-fluoride glass and reduced by using a coincidence system with Ge(Li) and NaI(T1) detectors. Substoichiometric separation of18F was also used to determine oxygen in fluoride glass, especially in glass containing yttrium as a component element because the89Zr produced by the89Y(p,n) reaction is a positron emitter, the same as18F. It was confirmed that the oxygen concentration in fluoride glass was 13–2460 ppm related to the loss by scattering.  相似文献   

8.
Summary A rapid method has been developed for the determination of phosphate by means of filter paper impregnated with lead iodide. A sample is added to the impregnated filter paper by means of a capillary, and after irrigation to cause migration of the ions a white spot is obtained as the lead iodide is converted into the phosphate. The weight of the spot is dependent on the pH and the quantity of phosphate present.The determination is possible in the presence of SCN, Cl, Br, NO3 , CO3 , I, IO3 , CH3COO, B4O7 2–, F, Sb2O7 4–, K+, Na+, NH4 +, OH, H+, succinic, citric and tartaric acids. The determination is impossible in the presence of C2O4 2–, SO4 2–, MoO4 2–, NO2 , SO3 2–, S2–, CrO4 2–, or CO3 2–.The method permits the determination of 7–100g of phosphate with an accuracy of 2%.
Zusammenfassung Ein schnelles Verfahren zur Phosphatbestimmung wird besehrieben, bei dem man sich eines mit Bleijodid imprägnierten Filterpapiers bedient. Die Probe wird mit einer Kapillare auf das Papier aufgebracht. Man erleichtert die Ionenbewegung durch geeignete Befeuchtung und erhält einen weißen Fleck infolge Umsetzung des Bleijodids in -phosphat. Das Gewicht des Fleckens hängt vom pH und von der Phosphatmenge ab.Die Bestimmung ist möglich in Gegenwart von SCN, Cl, Br, NO3 , CO3 , J, JO3 , CH3COO, B4O7 2–, F, Sb2O7 4–, K+, Na+, NH4 +, OH, H+, Bernsteinsäure, Zitronensäure und Weinsäure; sie ist nicht möglich bei Gegenwart von C2O4 2–, SO4 2–, MoO4 2–, NO2 , SO3 2–, S2–, CrO4 2– oder CO3 2–. 7 bis 100g Phosphat können mit einer Genauigkeit von 2% bestimmt werden.

Résumé On a développé une méthode rapide pour le dosage des phosphates sur papier-filtre imprégné d'iodure de plomb. On dépose l'échantillon sur le papier-filtre imprégné, à l'aide d'un capillaire, et, après humidification pour provoquer la migration des ions, on obtient une tache blanche quand l'iodure de plomb est converti en phosphate. Le poids de la tache dépend du pH et de la quantité de phosphate présent.Le dosage est possible en présence de SCN, Cl, Br, NO3 , CO3 , I, IO3 , CH3COO, B4O7 2–, F, Sb2O7 4–, K+, Na+, NH4 +, OH, H+, et des acides succinique, citrique et tartrique. Il est impossible en présence de C2O4 2–, SO4 2–, MoO4 2–, NO2 , SO3 2–, S2–, CrO4 2– ou CO3 2–.La méthode permet le dosage de 7 à 100g de phosphate avec une précision de 2%.
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9.
Patterning of TiO2 thin films was successfully obtained on different self-assembled monolayers (SAMs) in aqueous solution by micro-contact printing (μCP) method. The substrates were immersed in an aqueous solution containing titanium sulfate (Ti(SO4)2) and hydrogen peroxide for deposition at 80 °C. The growth rates on various surfaces were as follows: sulfonic (–SO3H) > amino (–NH2) > methyl (–CH3) > hydroxyl (–OH). According to the XPS results, SAMs with the terminal groups of –SO3H and –NH2 were favorable for the deposition. The TiO2 film deposited on the SAM with the terminal group of –CH3 could be easily peeled off. Clearly, TiO2 patterns were obtained on the prepatterned surfaces of –SO3H/–CH3 and –NH2/–CH3 SAMs. The deposition mechanism might be relevant to electrostatic interaction, Stern layer, lone pair electrons and Van der Vaals forces. The TiO2 film was anatase after annealing at 500 °C and comprised particles with an average diameter of ca. 10 nm.  相似文献   

10.
In the reaction of acetaldehyde, formaldehyde and ammononia over HZSM-5 (Si/Al-280), PbZSM-5 and WZSM-5 catalysts at 420°C, 0.5 h–1 weight hourly space velocity, the total yields of pyridine and 3-picoline obtained were 58.2, 42.8 and 78.3 wt.% based on aldehydes, respectively. In the reaction of acetaldehyde and ammonia over typical Pb–SiO2–Al2O3 (20% PbO), W–SiO2–Al2O3 (10% W), Pb–Cr–SiO2–Al2O3 (F) and Pb–Cu–SiO2–Al2O3 (E) catalysts at 420°C, 0.5 h–1 W.H.S.V., the yields of 2- and 4-picolines obtained were 51.1, 66.1, 80.6 and 53.7 wt.%, respectively.IICT Communication No. 3421, — dedicated to Dr. A.V. Rama Rao on his 60th birthday.  相似文献   

11.
Summary Kinetics of formation of [PdCl4]2– from [Pd(ox)2]2– and [Pd(mal)2]2– has been studies in aqueous acid media in the presence of an excess of chloride ion by stopped-flow spectrophotometry. Both the complexes undergo the transformation in two well separated consecutive steps. In 0.02–0.05 M acid with 0.2 M Cl, Pd(AA)2– dissociates leading to the formation of [Pd(AA)Cl2]2– (where AA =ox2– or mal2–), which in 0.1–0.6 M acid and 1 M Cl forms [PdCl4]2– in a relatively slow step. For both steps kabs=k0+k2[H+][Cl]. Activation parameters corresponding to k0 and k2 have been determined. Results indicate that [Pd(mal)2]2– is much more labile to substitution than [Pd(ox)2]2– and for both the lability is far greater than that of [Pd(bigH)2]2+ and [Pt(ox)2]2– reported earlier.  相似文献   

12.
The semiempirical PM3 method is used to calculate the potential functions of internal rotation of the functional groups –SO2Cl, –NO2, –CH3, –OCH3, and –NH2 of benzenesulfonyl halide molecules (PhSO2Hal, Hal = F, Cl, Br, I) and twelve substituted derivatives of benzenesulfonyl chloride. Molecular conformations have been determined and internal rotation barriers of the functional groups have been calculated. For meta- and para-substituted benzenesulfonyl chlorides, the projection of the S–Hal bond is perpendicular to the plane of the benzene ring. The rotation barriers of the –SO2Hal group of benzenesulfonyl halides increase in the series Hal = F, Cl, Br, I. The rotation barriers of the –SO2Cl group of benzenesulfonyl chloride with meta- and para-substituents slightly increase with the electron-donor properties of the substituent. The rotation barriers of the functional groups of ortho-substituted benzenesulfonyl chlorides are 3 or 4 times as high as those of the meta- and para-isomers. For para-substituted benzenesulfonyl chlorides, the rotation barriers of the functional groups increase in the order –CH3, –NO2, –SO2Cl, –OCH3, –NH2.  相似文献   

13.
Field desorption has been applied to research the thermal stability of the compounds Kn[Co(CN)5X], where X=SO3 2–, CN, NO2 , NO, Cl, Br, I, and H2O. A likely mechanism is proposed for the thermal decomposition. There is a correlation between the tetragonal-distortion parameters and the temperature of onset of destruction for the [Co(CN)5X]n– anion.Translated from Teoreticheskaya i Éksperimental'naya Khimiya, Vol. 21, No. 1, pp. 111–115, January–February, 1985.  相似文献   

14.
Dissociative and nondissociative electron attachment in the electron impact energy range 0–14 eV are reported for SOF2 SOF4, SO2F2, SF4, SO2, and SiF4 compounds which can be formed by electrical discharges in SF6. The electron energy dependences of the mass-identified negative ions were determined in a time-of-flight mass spectrometer. The ions studied include F and SOF 2 –* from SOF2; SOF 3 and F from SOF4; SO2F 2 –* , SO2F, F 2 , and F from SO2F2; SF 4 –* and F from SF4; O, SO, and S from SO2; and SiF 3 and F from SiF4. Thermochemical data have been determined from the threshold energies of some of the fragment negative ions. Lifetimes of the anions SOF 2 –* , SO2F 2 –* , and SF 4 –* are also reported.  相似文献   

15.
Summary A differential pulse polarographic method has been applied to the determination of trace concentrations of TeO 4 2– , TeO 3 2– , AsO 2 and VO 3 . The dependence of the differential pulse peak on various parameters was studied and optimum conditions for the analytical determination of these oxyanions were found. Limits of detection and quantitation have been calculated for the differential pulse polarographic determination of the investigated oxyanions. The selectivity of this technique for the determination of binary (TeO 4 2– -TeO 3 2– , TeO 4 2– -AsO 2 and TeO 4 2– -VO 3 ) mixtures and a ternary (TeO 4 2– -TeO 3 2– -AsO 2 ) mixture has also been reported.
Spurenbestimmung von TeO 4 2– , TeO 3 2– , AsO 2 und VO 3 durch Differential-Puls-Polarographie und Trennung binÄrer sowie ternÄrer Gemische von ausgewÄhlten Oxyanionen
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16.
Organylchlorosilanes, and also SiCl4, decompose 1,1,3,3-tetra- and hexamethyl-disilazanes with formation of hitherto unknown organylchlorosilazanes of general formulas R4–nSiCln–1NHSiH(CH3)2 and R4–nSiCln–1NHSi(CH3)3 (n=2–4) in yields of 54–98%. The IR and mass spectra of the prepared compounds were studied.Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 5, pp. 1159–1162, May, 1991.  相似文献   

17.
    
Zusammenfassung Eine dünnschichtchromatographische Trennung von NO2 , S2O3 2–, CrO4 2–, N3 , CN, SCN, BO3 3– S2–, AsO3 3–, AsO4 3–, NO3 , SO4 2– und PO4 3– wird beschrieben. Als Adsorbens dient Maisstärke. Die Identifizierung wird mit Hilfe von sechs selektiven Reagentien vorgenommen.
Summary A thin-layer chromatographic separation of NO2 , S2O3 2–, CrO4 2–, N3 , CN, SCN, BO3 3–, S2–, AsO3 3–, AsO4 3–, NO3 , SO4 2–, and PO4 3– ions is described. Maize starch is used as carrier substance. The identification dies anions has been achieved by six selective reagents.
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18.
The influence of anions ClO4 , NO3 , Cl, SO4 2–, and DDS (dodecyl sulfate) on the cyclic voltammetric response of polypyrrole-modified electrodes is studied. The change in the film composition is examined by electron probe microanalysis. It is established that essential changes in the shape of voltammograms take place during cycling if the anions are not sufficiently freely mobile in the polymer film and insertion of cations from the solution is necessary to guarantee electroneutrality of the system. Some differences between the mobility of Cl ions and ClO4 or NO3 ions are in good agreement with the results of semi-empirical quantum chemical calculations showing that the interaction of Cl and Br ions with pyrrole oligomers is stronger than that of NO3 or ClO4 ions. Nevertheless, it is established that the peak current determined from voltammograms increases linearly with the increase of the scan rate with very high correlation coefficient. It means that it is possible to describe the behavior of ClO4 , NO3 and Cl ions in the framework of the model of free ions. The redox behavior of the PPy films doped with anions of low mobility such as SO4 2– and DDS depends essentially on the nature of cations in the test solution. It is found that the mobility of cations increases in the row Li+ < Na+ < K+ < Cs+. The mobility of DDS ions in the PPy in ethanolic solution is significantly higher and their electrochemical properties are quite similar to PPy|Cl or NO3 film in aqueous solution.  相似文献   

19.
The interaction of iron carbonyls Fe n (CO) m (wheren = 1,m = 5;n = 2,m = 9;n = 3,m = 12) with anionic Lewis bases (H, F, Cl, Br , I, CN, SCN, N3 , MeSO3 , MeCO2 , CF3CO2 , S2 , CO3 2–, and SO4 2–) passes through two-stage redox-disproportionation. The first stage is the formation of an iron carbonyl-base complex, [Fe n (CO) m–1C(O)L], and the second is a single-electron reduction of this complex by another molecule of the initial iron carbonyl, giving rise to Fe(l) and Fe(–l) derivatives.Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 1, pp. 248–249, January, 1996.  相似文献   

20.
Summary Salts of the anions [SnX5], [SnX4Cl, [SnX3Cl2], [SnX3], [PbX3], [SbX4], [SbX3Cl], [SbX2Cl2], [BiX4], [AuCl2], [AuX2], [AuXCl], [AuX4], [Au2X6]2– and [PtX4]2–, where X = C6F5S, have been isolated and characterised. The neutral SbX3 and BiX3 species, have also been isolated and shown to be pyramidal monomers (19F.n.m.r., i.r., and Raman spectral evidence). Various physical properties of the complexes prepared, as well as their stereochemistries (where these could be ascertained), are similar to those of the known corresponding halogeno compounds of these elements. These results further demonstrate the pseudo-halide nature of the pentafluorothiophenoxide ion.Author to whom all correspondence should be directed at: Laboratoire de Chimie de Coordination, Uniyersité Louis Pasteur, 67008 Strasbourg, France.  相似文献   

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