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The mechanism for producing slow, target associated particles in high energy heavy ion collisions is investigated. It is shown that the same mechanism which was proposed for hadron induced interactions is likely to appear also for heavy-ion reactions. The results indicate however a much weaker correlation between impact parameter and yield of slow particles.  相似文献   
94.
Condensation of bis(2-furanthiocarboxyhydradatometal(II), M(fth)2; [M (II) = Mn, Fe, Co, Ni, Cu and Zn] with pyridine-2- and -4-carboxaldehydes gave complexes of the formula M(pfth)2 [pfth? = pyridine-2-carboxaldehyde-2-furanthiocarboxyhydrazonato], Ni(Ifth)2, Zn(Ifth)2, Cu(Ifth) and Co(Ifth)3, (Ifth? = pyridine-4-carboxaldehyde-2-furanthiocarboxyhydrazonato). The magnetic and electronic spectral studies coupled with photoacoustic or Mössbauer spectra suggested octahedral geometry for the M(II) complexes with low-spin states for Co(Ifth)3 and Fe(pfth)2. IR and 1H NMR spectral studies of diamagnetic complexes suggested bonding through “azomethine” nitrogen and “thiolo” sulphur. IR spectra also showed the involvement of pyridine ring nitrogen in coordination in all the complexes except Cu(Itfh), Co(Ifth)3, and Zn(Ifth)2. Some of the compounds possessed antimicrobial activity.  相似文献   
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We have studied the mean free path of He fragments from projectile beams of Ar, Fe and Kr of energy 1 ? E ?2A GeV at different distances (L ? 2.5 cm) from their production point and found that they are the same, independent of their (i) energy, (ii) target size, (iii) target excitation, (iv) He multiplicities and (v) production angles.  相似文献   
98.
The technique of four-wave mixing spectroscopy has been utilized to study the magnetic field dependence of the valley-orbit splitting, 4△(B), of As donors in Ge at 1.8°K for ⊥ [111]. The upper ground level, ls(T2), splits into two levels, one of “high” and the other of “low” diamagnetism. For donor concentration ND ? 5 × 1015 cm-3 we have measured the diamagnetism and g-factor for the high diamagnetism level (g ? 1.07) as a function of (< 7 T). Transitions originating from both spin-up and spin-down levels are observed, indicating that the spins are heated during the 100 n-sec laser pulse. Excellent agreement between measured and theoretical values of 4▽(B) is found (employing no adjustable parameters) if magnetic field compression of the wavefunction is taken into account.  相似文献   
99.
The combined use of 1H NMR spectroscopy with theoretical calculations of chemical shifts (GIAO) and coupling constants (B3LYP/6-311 ++G**) of a 5-hydroxy-5-trifluoromethyl-Delta2-isoxazoline has enabled solving the problem of the assignments of the diastereotopic protons in this compound. This result has been extended to 5-hydroxy-5-trifluoromethyl-Delta2-pyrazolines and the corresponding 5-trichloromethyl derivatives.  相似文献   
100.
Metal(II) complexes of N-(thiophene-2-carboxamido)salicylaldimine (H2TCS) of types M(H2TCS)2Cl2 [M = Ni, Cu and Zn], M(HTCS)Cl [M = Co, Ni and Cu], M(HTCS)2 [M = Mn, Fe, Co, Ni, Cu and Zn], M(TCS)·xH2O [M = Mn, Co and Ni, x = 2; M = Cu, x = 0], Ni(TCS)py2 and Cu(TCS)py have been prepared. Elemental analyses, molar conductance, magnetic moment, electronic, IR and ESR spectral studies have been used to characterize these complexes. The different modes of chelation of the ligand and the stereochemistry of the complexes are discussed.  相似文献   
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