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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.
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
3.
V. F. Chuvaev M. N. Rodnikova N. S. Kucherepa 《Russian Journal of Inorganic Chemistry》2008,53(12):1925-1928
A sample of 4′-(pentyloxy)-4-biphenylcarbonitrile was studied in the temperature range 20–70°C by wide-line 1H NMR. The line shapes, half-widths, and second moments were determined. At 20°C, the spectrum is a broad structureless line, which was split into three components at temperatures above 47°C. This pattern persisted up to 65°C, with the components becoming narrower. Above 68°C, the spectrum rapidly collapses to give a structureless narrow line with a width δH < 0.01 G. Analysis of the spectra and comparison with theoretical calculations made it possible to elucidate the transition of the sample from the crystalline to the nematic and isotropic phases, as well as to determine the temperature range of the stability of the liquid-crystalline phase and the role of rotational mobility of protons of different functional groups and sometimes of these groups as a whole in the mechanisms of phase transitions. 相似文献
4.
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
5.
Justyna Marganiec-Gałązka Ole J. Nähle Karsten Kossert 《Journal of Radioanalytical and Nuclear Chemistry》2017,314(2):599-604
The activity concentration of an 88Y solution was measured by means of a new custom-built 4πβ(LS)-γ coincidence counting system. Efficiency variation was carried out using chemical quenching and neutral density filters. A relative uncertainty of 0.57% was obtained for the activity concentration. Details of the measurements and of the analysis, as well as possibilities to reduce the uncertainty are discussed. Additional validation measurements were carried out by means of the well-established coincidence counting technique using a proportional counter (PC) in the β channel. The results of both coincidence methods were found to be in excellent agreement. 相似文献
6.
I. S. Nizamov L. A. Al’metkina E. N. Nikitin G. R. Sabirzyanova A. R. Burilov M. A. Pudovik 《Russian Journal of Organic Chemistry》2011,47(10):1504-1507
Reactions of 2,4-diaryl-1,3-dithia-2λ5,4λ5-diphosphetane 2,4-disulfides with tetraheptylcalix[4]-resorcinarene and octa-O-(2-hydroxyethyl)tetraoctylcalix[4]resorcinarene gave the corresponding octakis(aryldithiophosphonic acids). 相似文献
7.
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
8.
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
9.
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
10.
Inspired by carbo-benzene and its inorganic analogues, in the current work, the viability of extended systems (called carbomers) formed from aromatic small rings was studied. The aluminum aromatic cluster, Al42?, and its isoelectronic carbon analogue, C42+, were employed as starting point. The insertion of alkynyl units into the Al–Al and C–C bonds results in the extended molecules named carbomers. These molecules were compared with the global minima structures, which were searched employing the genetic algorithm program, GEGA. The electronic delocalization (aromaticity) of the isomers was studied with the induced magnetic field (Bind). The results showed that global minimum of C122+ (formed from C42+) was an unexpected diatropic structure which presented a similar magnetic response to the C42+ cluster. Also, optical properties of C122+ were computed. 相似文献
11.
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
12.
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
13.
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
14.
Fatemeh Hesami Gholam Hossein Rounaghi Massoumeh Mohajeri Somayeh Tarahomi 《Journal of solution chemistry》2011,40(8):1408-1417
The complexation reactions of 4′-nitrobenzo-15-crown-5 (4′NB15C5) with Zn2+, Mn2+, Cr3+ and Sn4+ cations were studied in acetonitrile–ethanol (AN–EtOH) binary solvent mixtures at different temperatures by the electrical
conductometry method. The stability constants of the resulting 1:1 complexes were determined from computer fitting of the
conductance versus mole ratio data. The results show that the selectivity order of 4′NB15C5 for the metal cations in the AN–EtOH
(mol-%AN=76) binary solvent at 298.15 K is: Cr3+>Mn2+≈Zn2+>Sn4+, but the selectivity order changes with the composition of the mixed solvents. A nonlinear relationship was observed between
the stability constants (log 10
K
f) of these complexes and the composition of the AN–EtOH binary solvents. The corresponding thermodynamic parameters (DHco, DSco)(\Delta H_{\mathrm{c}}^{\mathrm{o}}, \Delta S_{\mathrm{c}}^{\mathrm{o}}) were obtained from the temperature dependence of the stability constants using van’t Hoff plots. The results show that the
values and also the sign of these parameters are influenced by the nature and composition of the mixed solvents. 相似文献
15.
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
16.
Yu. V. Rakitin V. T. Kalinnikov S. G. Khodasevich V. M. Novotortsev 《Russian Journal of Coordination Chemistry》2007,33(12):891-895
The electronic structures of the complex ions [CuCl4]2? and [CuCl5]3? were analyzed in terms of the extended angular overlap model (AOM) with consideration to sd and pd mixing. The total antibonding orbital energies of these ions show no anomalies in the transition from a tetrahedron to a planar square [CuCl4]2? and from a trigonal bipyramid to a tetragonal pyramid [CuCl5]3?. Presumably, the existence of numerous intermediate forms of these complexes is mainly due to the packing effects rather than the electronic factors. 相似文献
17.
P. B. Fabrichnyi M. V. Korolenko V. E. Tkachenko M. Danot C. Payen 《Russian Journal of Inorganic Chemistry》2007,52(8):1262-1268
The hyperfine structure of the low-temperature Mössbauer spectra of dopant 119Sn4+ ions (0.4 at. %) in a fine crystalline MnO sample, characterized by X-ray diffraction and magnetic measurements, has been studied. The 119Sn spectra show that tin is distributed over positions with an inhomogeneous cationic environment. The appearance of such positions is explained by the local compensation for the excess charge of Sn4+ by manganese vacancies V Mn and segregation of defects resulting in precipitation of MnSnO3 clusters. The non-uniform distribution of Sn4+ and the related dependence of the number of broken magnetic bonds on the local tin concentration are responsible for the fluctuation of the T N values, which is “perceived” by 119Sn in different MnO crystallites. The 119Sn spectra exclude the possibility that tin enters into the composition of superpara-magnetic particles. 相似文献
18.
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
19.
Patrícia Severino Samantha C. Pinho Eliana B. Souto Maria H. A. Santana 《Journal of Thermal Analysis and Calorimetry》2012,108(1):101-108
This study focuses on the physicochemical characterization of lipid materials useful for the production of the so-called solid lipid nanoparticles (SLN) and nanostructured lipid carriers (NLC). The chosen lipids were Dynasan®114 (glyceril trimyristate) and Dynasan®118 (glyceril tristearate) as solid lipids (SL), melting temperature above 80 °C, and Miglyol®812 (caprylic/capric triglyceride) and Miglyol®840 (propylene glycol dicaprylate/dicaprate) as liquid lipids (LL), crystallizing below ?15 °C. Raw lipids (pure or SL:LL mixtures) were analyzed by differential scanning calorimetry (DSC), wide angle X-ray diffraction (WAXD), and Polarized Light Microscopy (PLM), before and after tempering at 80 °C for 1 h. The selected SL:LL combination was 70% (Dynasan®114 and 118) and 30% (Miglyol®812 and 840) for the production of SLN and NLC by high-pressure homogenization (HPH), respectively. Particles with a mean size of 200 nm (polydispersity index <0.329) and zeta potential of ?15 mV were obtained, and their long-term stability was confirmed for 3 months of storage at 7 °C. 相似文献
20.
V. V. Sharutin I. V. Egorova N. N. Klepikov O. K. Sharutina 《Russian Journal of Inorganic Chemistry》2010,55(7):1103-1106
The complex [Ph3P] 4 + [Bi4I16]4? · 2 Me2C=O (I) was synthesized by the reaction of triphenyl(propyl)phosphonium iodide with bismuth iodide in acetone. The crystal structure of complex I was determined by X-ray crystallography. It contains, in addition to solvent molecules, two types of crystallographically independent tetrahedral tetraphenyl(propyl)phosphonium cations and tetranuclear anions [Bi4I16]4? in a chair conformation with the bismuth atoms being in an octahedral coordination. The Bi-I distances in the anion vary within 2.8768(4)–3.2524(4) Å. 相似文献