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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.
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
3.
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
4.
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
5.
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
6.
A. V. Ivanov I. A. Lutsenko M. A. Ivanov A. V. Gerasimenko O. N. Antzutkin 《Russian Journal of Coordination Chemistry》2008,34(8):584-593
Platinum(II) O,O′-dicyclohexyl dithiophosphate [Pt{S2P(O-cyclo-C6H11)2}2] (I) and platinum(II) O,O′-diisopropyl dithiophosphate [Pt{S2P(O-iso-C3H7)2}2] (II) complexes were obtained and studied by solidstate 13C, 31P, and 195Pt CP/MAS NMR spectroscopy. The dithiophosphate (Dtph) ligands in molecular structure I were found to be coordinated by platinum in S,S′-bidentate fashion to form the planar chromophore [PtS4] (single-crystal X-ray diffraction data). For complex II, a new α-form (α-II) was obtained and identified by 31P MAS NMR spectroscopy. The 31P chemical shift anisotropy δaniso and the asymmetry parameter η of the 31P chemical shift tensor were calculated from the whole MAS spectra. 相似文献
7.
T. S. Shestakova I. A. Khalymbadzha S. L. Deev O. S. Eltsov V. L. Rusinov Z. O. Shenkarev A. S. Arseniev O. N. Chupakhin 《Russian Chemical Bulletin》2011,60(4):729-732
Selective methods for the incorporation of stable isotopes 15N and 2H into the structure of antiviral medicine “triazavirine” 1 were developed. The synthesized isotopically modified “triazavirine” 1–
2
H
3
,
15
N
3
contained the labeled atoms in both the azole and the azine rings. 13C and 15N NMR spectra of the isotope-containing sample 1–
2
H
3
,
15
N
3
were thoroughly analyzed. 相似文献
8.
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
9.
Ab initio quantum-chemical calculations of the complexes XeF 5 + XF 6 ? (X = P, As, Sb, and Bi) were performed with the use of relativistic pseudopotentials for heavy atoms and full-electron basis sets. The chemical bonds were characterized by the parameters of critical points (electron density, its Laplacian, total electron energy, and its kinetic and potential components). It was demonstrated that the interaction between the XeF 5 + cation and the XF 6 ? anion in XeF 5 + XF 6 ? follows a key-lock scheme involving directed interactions of bridging fluorine atoms Fb → Xe and that the structuring function of the lone electron pair of the Xe atom is to compensate the destabilizing electrostatic interaction between the Xe and X atoms bearing excess positive charges. 相似文献
10.
The structures of a closo-hedral cluster (HAlNH)12 and endohedral complexes 4/2X@(HAlNH)12 (X = N, P, As, C−, Si−) are studied by density functional theory (DFT) at the B3LYP/6-31G(d) level. The geometries, natural bond orbital (NBO), vibrational frequency (ν1), energetic parameters, magnetic shielding constants (σ), and nucleus independent chemical shifts (NICSs) are discussed.
It is found that all guest species are minima at the cage center. Inclusion energies (ΔE
inc) of all species are negative except those of 4N and 4/2P. In all species, the endohedral quartet states (4X) are energetically less favorable than their doublet states (2X). The calculations predict that caged X states only donate <0.50 e to the cage and preserve their unencapsulated ground
states. 相似文献
11.
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
12.
Özlem Karadeniz Günseli Yaprak 《Journal of Radioanalytical and Nuclear Chemistry》2011,288(1):261-270
The present work is devoted to an investigation on the soil to mushroom transfer parameters for 137Cs and 40K radionuclides, as well as for some stable elements and heavy metals. The results of transfer factors for 137Cs and 40K were within the range of 0.06–3.15 and 0.67–5.68, respectively and the most efficiently transferred radionuclide was 40K. The TF values for 137Cs typically conformed to a lognormal distribution, while for 40K showed normal distribution. Statistically significant correlations between 137Cs soil to mushroom transfer factors and agrochemical soil properties have been revealed. Although the concentration ratios
varied within the species, the most efficiently transferred elements seems to have been K, followed by Rb, Zn, Cu, Cd, S,
Cs and Hg. 相似文献
13.
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
14.
Ayagoz Baimukhanova Valery Radchenko Ján Kozempel Atanaska Marinova Victoria Brown Vasily Karandashev Dimitr Karaivanov Paul Schaffer Dmitry Filosofov 《Journal of Radioanalytical and Nuclear Chemistry》2018,316(1):191-199
Utilization of (p, 4n) reaction channel for the production of medical radionuclides became very attractive with commercial availability of medium energy cyclotrons. Significantly higher yields and radionuclidic purity may open new perspectives for several novel and some of the radionuclides previously have not been considered due to production difficulties. In present work, we show the proof-of-principle study on the production of 86Y for Positron Emission Tomography imaging via radionuclide generator 86Zr → 86Y. Production suitability of 86Zr from natural yttrium target and radiochemical separation strategies were tested. In addition, two generator systems were proposed and evaluated. 相似文献
15.
\( {\text{CN}} (B^{2}\Sigma ^{ + } \to X^{2}\Sigma ^{ + } ) \) 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
16.
Tran Duc Thiep Truong Thi An Phan Viet Cuong Nguyen The Vinh Bui Minh Hue Le Tuan Anh A. G. Belov 《Journal of Radioanalytical and Nuclear Chemistry》2018,317(3):1263-1271
In this work, the isomeric ratio of 152m1Eu(8?)–152m2Eu(0?) produced from the 153Eu(γ, n)152Eu reaction have been measured in the whole giant dipole resonance region by the activation method. In order to improve the accuracy of the experimental results, the necessary corrections were made in the gamma activity measurements and data analysis. The results were discussed and compared with the similar data from literature to examine the excitation energy, the spin difference and the nuclear reaction channel effects and can be used for the interpretation on the structure of the nucleus and the mechanisms of nuclear reactions. The data for bremsstrahlung end-point energies of 19–23 MeV are first-time measurements. 相似文献
17.
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
18.
G. L. Sharipov A. A. Tukhbatullin P. V. Kovyazin L. V. Parfenova P. V. Ivchenko I. E. Nifant’ev 《Russian Chemical Bulletin》2015,64(12):2776-2779
This work describes a comparative study of tribo- and photoluminescence of metallocenes (Cp2HfCl2, Cp2TiCl2, Cp2ZrCl2, (CpMe)2ZrCl2, rac-Me2C(3-But-Cp)2ZrCl2, Ind*2ZrCl2). Occurring under mechanodestruction of polycrystals, triboluminescence of zirconium bis-cyclopentadienyl complexes, Cp2ZrCl2, (CpMe)2ZrCl2, and rac-Me2C(3-But-Cp)2ZrCl2 has been revealed for the first time. The triboluminescence spectrum in air is similar to the photoluminescence spectrum of zirconocene polycrystals. The triboluminescence spectrum does not show *N2 luminescence. Ne and Ar lines are observed in the triboluminescence spectrum in the atmosphere of these gases. An increase in the number of substituents in zirconocene ligands leads to a bathochromic shift of the emission band maximum in triboluminescence spectra of the complexes. Possible mechanisms of zirconocene triboluminescence excitation are discussed. 相似文献
19.
A. N. Charkin O. V. Dudarev A. N. Salyuk N. E. Shakhova V. I. Sergienko I. P. Semiletov 《Doklady Chemistry》2017,476(1):211-214
The first results of activity measurement of short-lived radium isotopes dissolved in water in the Anadyr River–Bering Sea transit system are presented. The trends of the radionuclide behavior after passage through high-gradient river–coastal sea water mixing zone were identified and the exchange rate of the horizontal mixing was determined. The 224Ra/223Ra activity ratio was used to construct the “radium age” model, which served for estimating the residence time of brackish water in the Anadyr River estuary. The factors affecting this value were elucidated. 相似文献
20.
Using three accurate potential energy surfaces of the 3A″, 3A′, and 1A′ states constructed recently, we present a quasi-classical trajectory (QCT) calculation for O + HCl (v = 0, j = 0) → OH + Cl reaction at the collision energies (E
col) of 14.0–20.0 kcal/mol. The three angular distribution functions—P(qr ) P(\theta_{r} ) , P(jr ) P(\varphi_{r} ) , and P(qr ,jr ) P(\theta_{r} ,\varphi_{r} ) , together with the four commonly used polarization-dependent differential cross-sections,
\frac2ps \fracds00 dwt , \frac2ps \fracds20 dwt , \frac2ps \fracds22 + dwt , \textand \frac2ps \fracds21 - dwt {\frac{2\pi }{\sigma }}\,{\frac{{d\sigma_{00} }}{{d\omega_{t} }}},\,{\frac{2\pi }{\sigma }}\,{\frac{{d\sigma_{20} }}{{d\omega_{t} }}},\,{\frac{2\pi }{\sigma }}\,{\frac{{d\sigma_{22 + } }}{{d\omega_{t} }}},\,{\text{and}}\,{\frac{2\pi }{\sigma }}\,{\frac{{d\sigma_{21 - } }}{{d\omega_{t} }}} are exhibited to get an insight into the alignment and the orientation of the product OH radical. There is a similar behavior
of the tendency scattering direction for the two triplet electronic states (3A″ and 3A′)—backward scattering dominates, however, forward scattering prevails for the case of 1A′ state. Also, obvious differences have been found in the stereo-dynamical information, which reveals the influences of the
potential energy surface and the collision energy. The degrees of polarization and the influence of the collision energy on
the stereo-dynamics characters of the title reaction are both demonstrated in the order of 3A′ > 3A″ > 1A′. 相似文献