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A. Breakstone G. Claesson H. B. Crawley G. M. Dallavalle K. Doroba D. Drijard F. Fabbri A. Firestone M. A. Faessler H. G. Fischer S. Y. Fung S. Garpman W. Geist G. Giacomelli R. Gokieli M. Gorbics C. R. Gruhn P. Hanke M. Heiden W. Herr T. J. Ketel E. E. Kluge J. W. Lamsa T. Lohse I. Lund R. Mankel W. T. Meyer G. Mornacchi T. Nakada I. Otterlund M. Panter H. Pugh A. Putzer K. Rauschnabel B. Rensch F. Rimondi M. Schmelling G. P. Siroli R. Sosnowski E. Stenlund M. Szczekowski R. Szwed O. Ullaland R. Walczak D. Wegener M. Wunsch 《Zeitschrift fur Physik C Particles and Fields》1986,30(4):507-512
The relative yields of kaons and protons compared with the yield of pions at highp T and polar angles θ away from 90° (in the range from 10° to 45°) are presented forpp, dd, and αα interactions at a centre-of-mass energy \(\sqrt {s_{NN} } = 31\) GeV per nucleon-nucleon collision. The measured particle ratios depend on the atomic mass numberA of the beam particles and on θ. TheA dependence of the ratios becomes stronger for largerp T and is more pronounced at smaller polar angles. 相似文献
44.
T. Al Adlouni F. Meyer C. Meyer A. Fayt 《International Journal of Infrared and Millimeter Waves》1986,7(3):405-419
The perpendicularv
8 band lying in the 1000–1100 cm–1 region has been studied from infrared and laser Stark, spectra. We were interested in the part of spectrum corresponding to the spectral range of the 9 m CO2 laser lines. Assignments of rovibrational lines with J'<40 and K'<6 have been made. About 100 Stark resonances have been assigned to 12 rovibrational transitions. Effective molecular constants and dipole moment have been determined with high accuracy. A list of close resonances with CO2 laser lines is given and may be used for optical pumping experiments. 相似文献
45.
G. Lhersonneau D. Weiler P. Kohl H. Ohm K. Sistemich R. A. Meyer 《Zeitschrift für Physik A Hadrons and Nuclei》1986,323(1):59-67
An isomeric state at 3,523 keV excitation energy in97Y with a half-life of 144(10) ms has been discovered with the fission-product separator JOSEF. This isomer is depopulated through aγ transition of 162 keV. AnE3 multipolarity for this transition is consistent with the measured conversion coefficients ofα K =0.98(20) andα T =1.00(19). Subsequent electromagnetic transitions populate several new97Y levels which have high spins. For the isomer the three-quasiparticle configuration [πg 9/2?ν(h 11/2,g 7/2)]27/2? is proposed. TheE3 transition with a strength about 2 single-particle units is supposed to be of the typeh 11 2/+1 →d 5 2/?1 . These findings provide evidence for the rapid shape transition atA?100 since they indicate shell-model character of 39 97 Y58 even at high excitation energies while the immediate neighbour 39 98 Y59 contains a rotational band based on a level at 495 keV. 相似文献
46.
In contrast to the classical method where a single molecule is designed to extract metal cations under specific conditions, dynamic covalent chemistry provides an approach based on the implementation of an adaptive dynamic covalent library for inducing the generation of the extractant species. This approach has been applied to the liquid–liquid extraction of copper(ii) nitrate based on a dynamic library of acylhydrazones constituents that self-build and distribute through the interface of a biphasic system. The addition of copper(ii) cations to this library triggers a modification of its composition and the up-regulation of the ligand molecules driven by coordination to the metal cations. Among these, one species has proven to be sufficiently lipophilic to play the role of carrier agent and its formation by component exchange enables the partial extraction of the copper(ii). The study of different pathways to generate the dynamic covalent library demonstrates the complete reversibility and the adaptability of the system. The detailed analytical investigation of the system provides a means to assess the mechanism of the dynamic extraction process.Phase transfer of Cu(ii) cations is achieved by component exchange in a dynamic covalent library of acylhydrazone ligands. B1/B2 component exchange leads to the generation of a lipophilic carrier agent that extracts Cu(ii) into chloroform. 相似文献
47.
The first basic mercurous tetrafluoroborate, Hg2(OH)[BF4], was obtained through a synproportionation reaction of red mercuric oxide, HgO, and elemental mercury in a 35% solution of HBF4 in water as colourless single crystals. The crystal structure (orthorhombic, Pbca, Z = 8, a = 985.0(1), b = 991.0(1), c = 1141.0(2) pm) contains [(HO)1/2—Hg—Hg—(OH)1/2]+ zig‐zag chains that are further connected via weak Hg—OH interchain interactions to layers between which the [BF4]— are located in an up and down fashion. 相似文献
48.
Gallagher LA Serron SA Wen X Hornstein BJ Dattelbaum DM Schoonover JR Meyer TJ 《Inorganic chemistry》2005,44(6):2089-2097
Photocurrent measurements have been made on nanocrystalline TiO2 surfaces derivatized by adsorption of a catalyst precursor, [Ru(tpy)(bpy(PO3H2)2)(OH2)]2+, or chromophore, [Ru(bpy)2 (bpy(PO3H2)2)]2+ (tpy is 2,2':6',2' '-terpyridine, bpy is 2,2'-bipyridine, and bpy(PO3H2)2 is 2,2'-bipyridyl-4,4'-diphosphonic acid), and on surfaces containing both complexes. This is an extension of earlier work on an adsorbed assembly containing both catalyst and chromophore. The experiments were carried out with the I3-/I- or quinone/hydroquinone (Q/H2Q) relays in propylene carbonate, propylene carbonate-water mixtures, and acetonitrile-water mixtures. Electrochemical measurements show that oxidation of surface-bound Ru(III)-OH2(3+) to Ru(IV)=O(2+) is catalyzed by the bpy complex. Addition of aqueous 0.1 M HClO4 greatly decreases photocurrent efficiencies for adsorbed [Ru(tpy)(bpy(PO3H2)2)(OH2)]2+ with the I3-/I- relay, but efficiencies are enhanced for the Q/H2Q relay in both propylene carbonate-HClO4 and acetonitrile-HClO4 mixtures. The dependence of the incident photon-to-current efficiency (IPCE) on added H2Q in 95% propylene carbonate and 5% 0.1 M HClO4 is complex and can be interpreted as changing from rate-limiting diffusion to the film at low H2Q to rate-limiting diffusion within the film at high H2Q. There is no evidence for photoelectrochemical cooperativity on mixed surfaces containing both complexes with the IPCE response reflecting the relative surface compositions of the two complexes. These results provide insight into the possible design of photoelectrochemical synthesis cells for the oxidation of organic substrates. 相似文献
49.
Rolf Meyer Zu Kcker Gerlinde Frenzen Bernhard Neumüller Kurt Dehnicke Jrg Magull 《无机化学与普通化学杂志》1994,620(3):431-437
Syntheses and Crystal Structures of the Phosphaneimine Complexes MCl2(Me3SiNPMe3)2 with M = Zn and Co, and CoCl2(HNPMe3)2 The molecular complexes MCl2(Me3SiNPMe3)2 (M = Zn, Co) have been prepared by the reaction of the dichlorides of zinc and cobalt with Me3SiNPMe3 in CH3CN and CH2Cl2, respectively, whereas the complex CoCl2(HNPMe3)2 has been prepared by the reaction of CoCl2 with NaF in boiling acetonitrile in the presence of Me3SiNPMe3. All complexes were characterized by IR spectroscopy and by crystal structure determinations. The complexes MCl2(Me3SiNPMe3)2 crystallize isotypically. ZnCl2(Me3SiNPMe3)2: Space group P212121, Z = 4, 2677 observed unique reflections, R = 0.024. Lattice dimensions at ?70°C: a = 1243.6; b = 1319.0; c = 1464.7 pm. CoCl2(Me3SiNPMe3)2: Space group P212121, Z = 4, 3963 observed unique reflections, R = 0,071. Lattice dimensions at ?80°C: a = 1236.3; b = 1317.4; c = 1457.6 pm. CoCl2(HNPMe3)2 · CH2Cl2: Space group Pbca, Z = 8, 1354 observed unique reflections, R = 0.055. Lattice dimensions at ?80°C: a = 1247.3; b = 998.4; c = 2882.4 pm. All complexes have monomeric molecular structures, in which the metal atoms are coordinated in a distorted tetrahedral fashion by the two chlorine atoms and by the nitrogen atoms of the phosphaneimine molecules. 相似文献
50.
LiTiCl3 is obtained as one example within an ample solid solution, Li24–2nTinCl24 (?4?n?10), by synpropotionation of TiCl3 and Ti in the presence of LiCl (2:1:3 molar ratio) in sealed tantalum tubes at 750°C. It crystallizes with the inverse spinel-type structure according to (Li0.67)[4](Li0.67Ti1.33)[4]Cl4 with, at 25°C, a = 1048.62(4) pm, space group Fd3m. Thermal expansion is linear with α = 4.85 × 10?5K?1 up to about 300°C and thereafter, when the migration of Li+ from tetrahedral to octahedral interstices becomes increasingly important, it exhibits a relative decrease resulting, finally, in the phase transition to a NaCl-type structure that is observed for the first time at about 575°C. 相似文献