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A small library of Fmoc-protected 3-arylated tyrosines was created by radical arylation. The new building blocks were successfully applied in the synthesis of two novel neurotensin receptor ligands. Both isomers showed high affinity for the human NTS2 receptor with K(i) values in the nanomolar range. Interestingly, subtype selectivity strongly depends on the configuration of the peptide in position 11. Isomer (11R)-3 displayed an excellent preference for NTS2 compared to NTS1.  相似文献   
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Summary The intermediate precipitate, resulting by thermal decomposition and stepwise hydrolysis of yttrium-nitrate, was investigated by chemical analysis, TG, IR, and X-ray powderdiagrams and was found to be a definite hydroxynitrate Y(OH)1.5(NO3)1.5·H2O. Thermal decomposition resulted in the oxynitrate YO0.75(NO3)1.5, stable from 140–280°C, which was characterized in an analogous manner.
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34.
We have reconstructed the radiative decays chi(b)(1P)-->Upsilon(1S)gamma and chi(b)(2P)-->Upsilon(1S)gamma in p&pmacr; collisions at sqrt[s] = 1.8 TeV, and measured the fraction of Upsilon(1S) mesons that originate from these decays. For Upsilon(1S) mesons with p(Upsilon)(T)>8.0 GeV/c, the fractions that come from chi(b)(1P) and chi(b)(2P) decays are [27.1+/-6.9(stat)+/-4. 4(syst)]% and [10.5+/-4.4(stat)+/-1.4(syst)]%, respectively. We have derived the fraction of directly produced Upsilon(1S) mesons to be [50.9+/-8.2(stat)+/-9.0(syst)]%.  相似文献   
35.
We report on first measurements with polarized electrons stored in a medium-energy ring and with a polarized internal target. Polarized electrons were injected at 442 MeV (653 MeV), and a partial (full) Siberian snake was employed to preserve the polarization. Longitudinal polarization at the interaction point and polarization lifetime of the stored electrons were determined with laser backscattering. Spin observables were measured for electrodisintegration of polarized 3He, with simultaneous detection of scattered electrons, protons, neutrons, deuterons, and 3He nuclei, over a large phase space.  相似文献   
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We have searched for direct production of scalar top quarks at the Collider Detector at Fermilab in 88 pb(-1) of p&pmacr; collisions at sqrt[s] = 1.8 TeV. We assume the scalar top quark decays into either a bottom quark and a chargino or a bottom quark, a lepton, and a scalar neutrino. The event signature for both decay scenarios is a lepton, missing transverse energy, and at least two b-quark jets. For a chargino mass of 90 GeV/c(2) and scalar neutrino masses of at least 40 GeV/c(2), we find no evidence for scalar top production and present upper limits on the production cross section in both decay scenarios.  相似文献   
38.
We report the first observation of dijet events with a double Pomeron exchange topology produced in &pmacr;p collisions at sqrt[s] = 1800 GeV. The events are characterized by a leading antiproton, two jets in the central pseudorapidity region, and a large rapidity gap on the outgoing proton side. We present results on jet kinematics and production rates, compare them with corresponding results from single diffractive and inclusive dijet production, and test factorization.  相似文献   
39.
Aiginger  H.  Maringer  F. J.  Német  J.  Rank  D.  Unfried  E. 《Acta Physica Hungarica》1986,59(1-2):95-98
Acta Physica Hungarica - At the Bundesversuchs- und Forschungsanstalt Arsenal, Vienna, a new lowlevel laboratory has been established for routine measurements of H3, C14 and other radionuclides in...  相似文献   
40.
Summary The chemical reactions involved were investigated in more detail and methods for treatment of larger quantities were developed. Contrary to former opinions, the hydrolysis of the partially decomposed melt is decisive for the quality of separation. The reaction of the melt with water occurs in two steps, and in both cases distribution coefficientsK of Er up to 4 could be achieved. From 12kg yttrium earth oxide around 8kg were prepared nearly free from Er and the heavierYE.
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