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1.
The inclusive cross-section for π0 production near 90° inpp collisions at the CERN Intersecting Storage Rings has been studied for thep T range 3<p T <16GeV/c at four different centre-of-mass energies ( \(\sqrt s = 30.6\) , 44.8, 52.7, and 62.8 GeV). In this experiment the two photons from the π0yy decay were resolved and measured separately forp T values up to 10 GeV/c. Results indicate an agreement with thep T ?8 behaviour for the lower values ofp T and a slower decrease of the cross-section for the higher values ofp T . The high-p T data deviate from the scaling expressionp T ?n F(x T ), which holds for the lowerp T values (p T <8GeV/c).  相似文献   
2.
The reactions of the potent and widely used anti-inflammatory drug diclofenac, HL, with diorganotin(IV) oxides were studied. The dimeric tetraorganodistannoxane complexes [Me(2)LSnOSnLMe(2)](2), [Bu(2)LSnOSnLBu(2)](2), [Ph(2)LSnOSnLPh(2)](2) and the dibutyltin complex [Bu(2)SnL(2)], have been prepared and structurally characterized in the solid state by means of vibrational and 119Sn M?ssbauer spectroscopy. Determination of lattice dynamics by temperature-dependent 119Sn M?ssbauer spectroscopy. From the variable-temperature M?ssbauer effect, the Debye temperature was determined. The complexes have been characterized in solution by NMR (1H and 13C) spectroscopy. Vibrational, M?ssbauer, and NMR data are discussed in terms of the proposed structures.  相似文献   
3.
A search for massive photon pair production at \(\sqrt s = 63 GeV\) has been carried out on the data sample previously employed for the electron pair production study. Positive evidence is reported form γγ>6GeV, with a production cross-section similar to Drell-Yan electron pairs. The ratio γγ/π0π0 was measured to be ~10?3 for ap T of each γ or γ or π0 above 3 GeV/c.  相似文献   
4.
The inclusive η production cross section at the CERN ISR has been measured for pT values of up to 11 GeV/c. We find that the ηπ0 cross-section ratio has an average value of 0.55 ± 0.07 and varies little with pT.  相似文献   
5.
We have measured direct photon production in pp collisions at the CERN intersecting storage rings for c.m. energies 31 < √s < 63 GeV and transverse momenta up to 9GeV/c, using segmented lead/liquid-argon calorimeters. The ratio of direct photon to π0 production is significantly larger than zero, starting at pT ≈ 4 GeV/c and increasing to values of about 0.4 at 9GeV/c. No significant √s dependence is seen.  相似文献   
6.
The cross-section for J/ψ production in proton-proton collisions has been measured as a function of centre-of-mass energy at the CERN Intersecting Storage Rings by observing its decay into electron-positron pairs. This cross-section is found to rise by a factor of about six over the full centre-of-mass energy range from √s=23 to √s=63 GeV. Electrons resulting from this decay were identified by the use of liquid argon calorimeters and lithium foil transition radiators. Measurements of the energies of the electrons were obtained from the liquid argon calorimeters.  相似文献   
7.
The inclusive production of π0 at large values of pT in pp collisions at the ISR has been studied. In this experiment the two photons are resolved and separately measured for pT values of up to 6 GeV/c, giving confidence that the desired signal has been separated from various backgrounds.  相似文献   
8.
9.
Molecular Diversity - Three known organo-antimony(III)–copper(I), mixed-metal small bioactive molecules (SBAMs) of formula [Cu(tpSb)3Cl] (1), [Cu2(tpSb)4Br2] (2) and [Cu2(tpSb)4I2] (3)...  相似文献   
10.
Five new antimony(III) complexes with the heterocyclic thiones 2-mercapto-benzimidazole (MBZIM), 5-ethoxy-2-mercapto-benzimidazole (EtMBZIM), and 2-mercapto-thiazolidine (MTZD) of formulas {[SbCl(2)(MBZIM)4]+.Cl-.2H(2)O. (CH(3)OH)} (1), {[SbCl(2)(MBZIM)4]+.Cl-.3H(2)O.(CH3CN)} (2), [SbCl(3)(MBZIM)2] (3), [SbCl(3)(EtMBZIM)(2)] (4), and [SbCl(3)(MTZD)2] (5) have been synthesized and characterized by elemental analysis, FT-IR, far-FT-IR, differential thermal analysis-thermogravimetry, X-ray diffraction, and conductivity measurements. Complex {[SbCl2(tHPMT)(2)]+Cl-}, (tHPMT = 2-mercapto-3,4,5,6-tetrahydro-pyrimidine), already known, was also prepared, and its X-ray crystal structure was solved. It is shown that the complex is better described as {[SbCl3(tHPMT)(2)]} (6). Crystal structures of all other complexes (1-5) have also been determined by X-ray diffraction at ambient conditions. The crystal structure of the hydrated ligand, EtMBZIM.H2O is also reported. Compound [C(28)H(24)Cl(2)N(8)S(4)Sb.2H(2)O.Cl.(CH(3)OH)] (1) crystallizes in space group P2(1), with a = 7.7398(8) A, b = 16.724(3) A, c = 13.717(2) A, beta = 98.632(11) degrees, and Z = 2. Complex [C(28)H(24)Cl(2)N(8)S(4)S(b).Cl.3H(2)O.(CH(3)CN)] (2) corresponds to space group P2(1), with a = 7.8216(8) A, b = 16.7426(17) A, c = 13.9375(16) A, beta = 99.218(10) degrees , and Z = 2. In both 1 and 2 complexes, four sulfur atoms from thione ligands and two chloride ions form an octahedral (Oh) cationic [SbS(4)Cl(2)]+ complex ion, where chlorides lie at axial positions. A third chloride counteranion neutralizes it. Complexes 1 and 2 are the first examples of antimony(III) compounds with positively charged Oh geometries. Compound [C(14)H(12)Cl(3)N(4)S(2)S(b)] (3) crystallizes in space group P, with a = 7.3034(5) A, b = 11.2277(7) A, c = 12.0172(8) A, alpha = 76.772(5) degrees, beta = 77.101(6) degrees, gamma = 87.450(5) degrees, and Z = 2. Complex [C(18)H(20)Cl(3)N(4)O(2)S(2)S(b)] (4) crystallizes in space group P1, with a = 8.6682(6) A, b = 10.6005(7) A, c = 13.0177(9) A, alpha = 84.181(6) degrees, beta = 79.358(6) degrees, gamma = 84.882(6) degrees, and Z = 2, while complex [C(6)H(10)Cl(3)N(2)S(4)S(b)] (5) in space group P2(1)/c shows a = 8.3659(10) A, b = 14.8323(19) A, c = 12.0218(13) A, beta = 99.660(12) degrees, and Z = 4 and complex [C(8)H(16)Cl(3)N(4)S(2)S(b)] (6) in space group P1 shows a = 7.4975(6) A, b = 10.3220(7) A, c = 12.1094(11) A, alpha = 71.411(7) degrees, beta = 84.244(7) degrees, gamma = 73.588(6) degrees, and Z = 2. Crystals of complexes 3-6 grown from acetonitrile solutions adopt a square-pyramidal (SP) geometry, with two sulfur atoms from thione ligands and three chloride anions around Sb(III). The equatorial plane is formed by two sulfur and two chloride atoms in complexes 3-5, in a cis-S, cis-Cl arrangement in 3 and 5 and a trans-S, trans-Cl arrangement in 4. Finally, in the case of 6, the equatorial plane is formed by three chloride ions and one sulfur from the thione ligand while the second sulfur atom takes an axial position leading to a unique SP conformation. The complexes showed a moderate cytostatic activity against tumor cell lines.  相似文献   
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