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1.
Abstract The title compound, labeled with 13C in the ethyl groups was synthesized from K13CN and low-molecular-weight components. The synthetic relay compound was 31(32)[13C]-xanthobilirubinic acid methyl ester in a synthetic route that leads to a label in the ethyl β-substituent of a dipyrrinone
model for bilirubin. This labeled dipyrrinone was oxidatively coupled to the dimethyl ester of mesobiliverdin-XIIIα, thereby
providing a route to a 13C-labeled mesobiliverdin and mesobilirubin, with one carbon of each ethyl being 98% 13C-enriched.
Graphical Abstract
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2.
As part of a mass spectrometric investigation of the binding properties of sulfonamide anion receptors, an atmospheric pressure
chemical ionization mass spectrometric (APCI-MS) method involving direct infusion followed by thermal desorption was employed
for identification of anionic supramolecular complexes in dichloromethane (CH2Cl2). Specifically, the dansylamide derivative of tris(2-aminoethyl)amine (tren) (1), the chiral 1,3-benzenesulfonamide derivatives of (1R,2S)-(+)-cis-1-amino-2-indanol (2), and (R)-(+)-bornylamine, (3), were shown to bind halide and nitrate ions in the presence of (n−Bu)4N+X− (X− = Cl−, NO3−, Br−, I−). Solutions of receptors and anions in CH2Cl2 were combined to form the anionic supramolecular complexes, which were subsequently introduced into the mass spectrometer
via direct infusion followed by thermal desorption. The anionic supramolecular complexes [M+X]−, (M=1–3, X−=Cl−, NO3−, Br−, I−) were observed in negative mode APCI-MS along with the deprotonated receptors [M−H]−. Full ionization energy of the APCI corona pin (4.5 kV) was necessary for obtaining mass spectra with the best signal-to-noise
ratios. 相似文献
3.
Makoto Takezaki Hiroyuki Aoki Michiko Kodama Toshihiro Tominaga 《Journal of Thermal Analysis and Calorimetry》2010,101(3):1149-1153
The solubility of hexadecyltrimethylammonium tetrachloroaurate (CTA·AuCl4) in water was measured at different temperatures of 288.2, 293.2, 298.2, 303.2, and 308.2 K. The enthalpy change associated
with the formation of the CTA·AuCl4 precipitate was estimated on the basis of the van’t Hoff equation and was found to be −42.5 ± 2.8 kJ mol−1 at 298.2 K. The calorimetric enthalpy change for the CTA·AuCl4 precipitate formation was directly determined by isothermal titration calorimetry performed at 298.2 K and was found to agree
well with that estimated from the van’t Hoff equation. 相似文献
4.
\( {\text{CN}} (B^{2}\Sigma ^{ + } \to X^{2}\Sigma ^{ + } ) \) violet system was investigated using optical emission spectroscopy in a non-equilibrium microwave atmospheric-pressure plasma jet in argon expanding in air. From the analysis of the emission spectra of the discharge in the range of 380 and 400 nm, the violet system of CN was found to be overlapped with the \( {\text{N}}_{2}^{ + } \left( {B^{2}\Sigma _{u}^{ + } , v = 1 \to X^{2}\Sigma _{g}^{ + } , v = 1} \right) \) and \( {\text{N}}_{2} \left( {C^{3}\Pi _{u} \to B^{3}\Pi _{g} } \right) \) bands, sequence \( \Delta \upsilon = - \;3 \). A numerical disentangle technique, developed in this work, permitted to obtain a well resolved violet system from the different systems observed, namely the nitrogen First Negative and the Second Positive systems. The \( {\text{CN}} (B^{2}\Sigma ^{ + } \to X^{2}\Sigma ^{ + } ) \) band head intensity was determined and analysed as function of discharge powers between 30 and 150 W and fluxes between 2.5 and 10.0 slm. With aid of this numerical approach it was also possible to obtain the rotational temperature, from (1600 ± 100) to (2300 ± 100) K and vibrational temperature between (9000 ± 800) and (14,000 ± 800) K along the plasma jet. The kinetics of \( {\text{CN}} (B^{2}\Sigma ^{ + } ) \) state was analysed as well. 相似文献
5.
F. Bousmina L. Zayani D. Ben Hassen-Chehimi N. Kbir-Ariguib M. Trabelsi-Ayedi 《Monatshefte für Chemie / Chemical Monthly》2003,134(5):763-768
Summary. The diagram of the ternary system Mg2+/Cl−, SO4
2−–H2O was established at 15°C by means of analytical and conductimetric measurements. Three compounds were found in this diagram,
which are MgSO4·6H2O, MgSO4·7H2O, and MgCl2·6H2O. The solubility field of MgSO4·7H2O is important whereas those of MgSO4·6H2O and MgCl2·6H2O are small. The compositions (mass-%) of the two invariant points determined by the two methods are: MgSO4:MgCl2=2.73:33.80 and MgSO4: MgCl2=3.38:28.91. Both the measured and the calculated isotherm at 15°C have been used for modelling of the diagram Mg2+/Cl−, SO4
2−–H2O between 0 and 35°C. The polythermal invariant point was approximately located between 15 and 10°C.
Corresponding author. E-mail: ariguib@planet.tn
Received October 16, 2002; accepted (revised) December 3, 2002
Published online April 24, 2003
RID="a"
ID="a" Dedicated to Prof. Dr. Heinz Gamsj?ger on the occasion of his 70th birthday 相似文献
6.
Silvia Dulanská Boris Remenec L’ubomír Mátel Igor Antalík 《Journal of Radioanalytical and Nuclear Chemistry》2012,292(1):97-101
Two separation techniques for plutonium determination using AnaLig® Pu02 molecular recognition technology product (MRT) and extraction chromatography TRU® resin were tested. The methods performance was investigated by analysis of National Physical Laboratory (NPL-Alpha-Beta High, ABH 2003, 2005) intercomparison test samples. The results obtained for both procedures were compared in terms of activities and recoveries. Data analysis showed good agreement with the reference values. The AnaLig® Pu02 separation method for 239,240Pu, 238Pu determination was successfully validated with the same performance as the TRU® resin method. 相似文献
7.
M. Kuzmanović V. Bojović J. Savović A. Antić-Jovanović 《Russian Journal of Physical Chemistry A, Focus on Chemistry》2009,83(9):1515-1519
Relative intensities of eight vibronic bands, belonging to the Δυ = −2 sequence of the B
2Σ+ −X
2Σ+ electronic transition of four GaO isotopomers have been measured and interpreted in terms of possible isotope effects on
the parameters governing the band intensity. Obtained results showed very small isotope effect on the Franck-Condon factors
and r-centroids and revealed that the observed intensity ratios of the corresponding isotope bands are controlled mainly by the
isotope abundance of 69Ga and 71Ga in natural gallium.
The article is published in the original. 相似文献
8.
F. Szelecsényi G. F. Steyn Z. Kovács K. Aardaneh C. Vermeulen T. N. van der Walt 《Journal of Radioanalytical and Nuclear Chemistry》2009,282(1):261-263
Experimentally measured cross-sections are presented for the first time for the 192Os(p,α3n)186Re nuclear reaction up to 67 MeV. Highly enriched thin 192Os targets (15 pcs), prepared by electro-deposition onto Cu backings, were irradiated with an external proton beam delivered
by the SSC cyclotron of iThemba LABS. The excitation function curve of the 192Os(p,α3n)186Re reaction shows a maximum cross-section of ~82 mb at about 24 MeV. According to the yield calculations based on the present
results, the available cumulative no-carrier-added 186Re yield is 7.76 MBq/μAh (0.21 mCi/μAh) over the energy region 13.4 → 27.3 MeV. 相似文献
9.
Cyclotron production of <Superscript>211</Superscript>At/<Superscript>211g</Superscript>Po by <Superscript>209</Superscript>Bi(α,2n) reaction 总被引:1,自引:1,他引:0
S. Morzenti M. L. Bonardi F. Groppi C. Zona E. Persico E. Menapace Z. B. Alfassi 《Journal of Radioanalytical and Nuclear Chemistry》2008,276(3):843-847
Astatine-211 (T
1/2 = 7.214 h) is an α-emitter at secular equilibrium by EC with its ultra-short-lived α-emitting daughter, polonium-211g (T
1/2 = 0.516 s), with a high Linear Energy Transfer (LET — 130 eV·nm−1) and a half-life suitable for metabolic radiotherapy; the overall α branching of the 211At/211gPo system is 100%. The direct production of 209Bi(α,2n)211At/211gPo seems the most satisfactory method; Bi targets were irradiated at JRC-Ispra Cyclotron of European Commission, EC, using
α-energy higher than 28.61 MeV in order to produce, via 209Bi(α,3n) reaction, small amounts of the γ-emitter 210At (used as internal spike). 相似文献
10.
P. Storoniak M. Kabir J. Błażejowski 《Journal of Thermal Analysis and Calorimetry》2008,93(3):727-732
The enthalpies of formation of PbCl4, PbCl5− and PbCl62−, originating from quantum mechanics, have enabled the thermodynamic behaviour of these ions with respect to Cl-detachment
to be assessed. The stability of salts containing PbCl5− and PbCl62− as a function of the dimensions of these anions and complementary cations was studied using an approach combining the Kapustinskii-Yatsimirskii
equation with basic thermochemical relationships.
It was found that hexachloroplumbates of monovalent metal cations will not dissociate into metal chlorides and PbCl4, provided the complementary cations are suitably large in size. Hexachloroplumbates of divalent metal cations have not yet
been synthesised since no known metal cations attain the requisite large size. Such salts will not dissociate if the divalent
metal cations are able to complex suitably large electron-donating ligands. The pentachloroplumbates of both monovalent and
divalent metal cations are unstable, since no known metal cations have appropriately large ionic radii. The approach adopted
appears to be useful for the examination of the thermal behaviour, stability and reactivity of chloroplumbates. 相似文献
11.
Hui-Jun Won Byambatseren Baigalmaa Jei-Kwon Moon Chong-Hun Jung Kune-Woo Lee Jae-Hyuk Hyun 《Journal of Radioanalytical and Nuclear Chemistry》2011,287(2):525-531
Type 304 stainless steel specimens artificially contaminated with CsCl solution were treated with KOH solution and KNO3 solution, respectively. Cs+ ion removal tests by a Q-switched Nd:YAG laser at 1064 nm at a given fluence of 57.3 J/cm2 were performed. The surface morphology and the relative atomic mole ratio of the specimen surface were investigated by SEM
and EPMA. The order of Cs+ ion removal efficiency of laser was no-treatment < KOH < KNO3 during the 42 shots. From the investigation of XPS peaks around 532.7 and 292.9 eV, KNO3 on a surface of specimen was found to be fully decomposed during the laser irradiation. It was suggested that Cs2O particulates formed by the reaction between the reactive oxygen generated from the nitrate ion and Cs+ ion on the metal surface could be easily suspended. For the KOH system, FeOOH was formed during the laser irradiation and
it changed into Fe2O3. It was also suggested that Cs2O particulates were formed by the reaction between the reactive oxygen generated from the decomposition of K2O and Cs+ ion on the metal surface.. 相似文献
12.
N. V. Aksenov H. Bruchertseifer G. Ya. Starodub G. K. Vostokin E. E. Tereshatov G. A. Bozhikov S. V. Shishkin S. N. Dmitriev 《Journal of Radioanalytical and Nuclear Chemistry》2009,279(1):341-343
A rapid method for the preparation of 87Y/87mSr radionuclide generator from a rubidium chloride target irradiated with 35 MeV α-particles is described. A simple two-step
procedure is used to obtain a carrier-free 87mSr isotope with a high enough radiochemical yield and high purity in the final aqueous fraction. 相似文献
13.
A. B. Azlarov Kh. M. Polvonov M. K. Askarova S. Tukhtaev 《Russian Journal of Inorganic Chemistry》2011,56(1):124-127
The solubility in the 2Na+,Mg2+‖2Cl−, 2ClO3−-H2O system was studied at 20 and 100°C and the solubility diagrams were plotted. New compounds were not found to form in the
title quaternary reciprocal system. The sodium chloride field was observed to expand with rising temperature. 相似文献
14.
Boukraa Yamina 《Russian Journal of Physical Chemistry A, Focus on Chemistry》2016,90(13):2642-2645
A study on the extraction of copper(II), cobalt(II), and nickel(II) from solutions containing ions of both metals with N-salicylideneaniline(SAN) in chloroform has been realized. Distribution of the metal ions in wide range of pH has been studied. Extraction of copper(II) was always favored over that of cobalt(II). Extraction of copper(II) from binary metal solution is selective and it can be quantitatively separated from cobalt(II). The equilibrium constant of the extraction of cobalt and nickel from an aqueous solution containing both metals using SAN were evaluated. The separation factors for cobalt and nickel were expressed as a function of the distribution of nickel and cobalt. From these results, salicylideneaniline is an adequate extractant for extractive separation of such mixtures. 相似文献
15.
16.
E. E. Karslyan D. S. Perekalin P. V. Petrovskii A. O. Borisova A. R. Kudinov 《Russian Chemical Bulletin》2009,58(3):585-588
The cation [CpRu(η6-C10H8)]+ was shown to exchange naphthalene for other arenes under visible-light irradiation to form the complexes [CpRu (η6-arene)]+ (arene = C6H6, 1,4-C6H4Me2, 1,3,5-C6H3Me3, or 1,2,4,5-C 6H2Me4) in 70–95% yields. The reaction rate of exchange decreases in the series arene = 1,4-C6H4Me2 > C6H6 > 1,3,5-C6H3Me3 > 1,2,4,5-C 6H2Me4 >> C6Me6 and increases with the coordinating ability of the solvent in the order CH2Cl2 < THF—CH2Cl2 mixture (1: 1) < acetone. 相似文献
17.
Potential energy curves of NgH+ cations (Ng = Kr, Xe, Rn) were obtained by using four-component relativistic CCSD(T) coupled cluster calculations. Dissociation
energies, equilibrium bond lengths, electronic properties, such as dipole moments and electric field gradients at the nuclei,
and the related spectroscopic parameters of the electronic ground state have been determined. The results obtained for KrH+ and XeH+ are in good agreement with available experimental data, while those for RnH+ have been determined for the first time at this level of theory. 相似文献
18.
V. V. Sharutin V. S. Senchurin O. K. Sharutina 《Russian Journal of Inorganic Chemistry》2012,57(3):398-401
The complex [(HOCH2)3CNH3] 2 + [HgI4]2? (I) was synthesized by reacting (trioxymethyl)methylammonium iodide with mercury dioide (2: 1 mol/mol) in acetone. X-ray crystallography shows that the complex consists of two types of crystallographically independent [(HOCH2)3CNH3]+ cations and tetrahedral anions [HgI4]2? (IHgI, 106.49(2)°–113.99(4)°; Hg-I, 2.7849(8)-2.8105(8) Å. [(HOCH2)3CNH3]+ cations are linked via hydrogen bonds O…H-N and O-H…N (O…N, 2.84–2.92 Å) to form polymer chains, which are cross-linked with one another via anions (I…H, 2.81, 2.82 Å). 相似文献
19.
E. M. Bond S. Glover D. J. Vieira R. S. Rundberg G. Belier V. Meot D. Hynek Y. Jansen J. Becker R. Macri 《Journal of Radioanalytical and Nuclear Chemistry》2008,276(2):549-554
This paper describes the preparation of samples for an experiment to measure the cross-section for 235U(n,n′)235mU in a fast fission spectrum of neutrons provided by a fast pulsed reactor/critical assembly. Samples of 235mU have been prepared for the calibration of the internal conversion electron detector that is used for the 235mU measurement. Two methods are described for the preparation of 235mU. The first method used a U-Pu chemical separation based on anion-exchange chromatography and the second method used an alpha
recoil collection method. Thin, uniform samples of 235mU+235U were prepared for the experiment using electrodeposition. 相似文献
20.
A. S. Kubasov E. Yu. Matveev E. S. Turyshev I. N. Polyakova K. Yu. Zhizhin N. T. Kuznetsov 《Doklady Chemistry》2017,477(1):257-260
The interaction of the [B10H10]2– and [B12H12]2– anions with aliphatic and aromatic nitro compounds (RNO2, where R = Et, n-Pr, i-Pr, tert-Bu, Ph) has been studied under irradiation with visible and UV light. It has been shown that, depending on the reaction conditions, both mono- and disubstituted nitro-closo-decaborates can be selectively obtained in yields up to 50%. 相似文献