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  • 1
    Electronic Resource
    Electronic Resource
    College Park, Md. : American Institute of Physics (AIP)
    The Journal of Chemical Physics 85 (1986), S. 5212-5220 
    ISSN: 1089-7690
    Source: AIP Digital Archive
    Topics: Physics , Chemistry and Pharmacology
    Notes: Susceptibility measurements of [Fe(OEP) (3-ClPy)] ⋅ ClO4(OEP=octaethylporphyrinate) in an external field of 1 T show that its magnetic moment varies from 3.36 to 4.58 β over a temperature range of 6–300 K. The data were analyzed with the "Maltempo model'' but could be fitted only when an antiferromagnetic exchange interaction between two neighboring iron atoms within the dimer structure was assumed. The analysis shows that the ground state quartet S=3/2 (81%) is mixed with the nearby sextet S=5/2 (19%) through spin-orbit coupling with an unusually small coupling constant, ζ=150 cm−1. The exchange interaction within the dimer is estimated to be in the range of J=−0.4 to −0.6 cm−1. Mössbauer spectra of a polycrystalline sample of this complex were recorded in a range of temperatures (1.54–128 K) and applied magnetic fields (0–6 T). The analysis of Mössbauer spectra was in excellent agreement with that of susceptibility data. The analysis favors J=−0.6 cm−1. The values of chemical shift, δ=0.36 mm/s (with respect to metallic Fe), and temperature independent quadrupole splitting ΔE=3.23 mm/s, are typical of ferric ions in the admixed-intermediate spin state. Mössbauer analysis also provides the hyperfine coupling constant, P/gNβN =36.3 T/unit spin, a very low value compared with 60 T/unit spin for hemoglobin fluoride. The spectra also show that the system relaxes slowly in the presence of an external field above 5 T at 4.2 K. The rate of relaxation increases if the field is decreased or the temperature is increased. Low temperature spectra with intermediate rates of relaxation could be fitted with the set of parameters mentioned above. Only the direct relaxation process seems to be responsible up to 8 K. The anomalously large value of ΔE and low values of ζ and P are discussed in terms of the formation of molecular orbitals and changing radial wave functions of the 3d orbitals in the admixed-spin states.
    Type of Medium: Electronic Resource
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  • 2
    Electronic Resource
    Electronic Resource
    College Park, Md. : American Institute of Physics (AIP)
    The Journal of Chemical Physics 83 (1985), S. 5945-5952 
    ISSN: 1089-7690
    Source: AIP Digital Archive
    Topics: Physics , Chemistry and Pharmacology
    Notes: Mössbauer spectra of polycrystalline [Fe(OEP)(2-MeHIm)]ClO4 ⋅ CHCl3 (OEP=octaethylporphyrinate; 2-meHIm=2-methylimidazole) were recorded over a range of temperatures (1.54 to 195 K) and applied magnetic fields (0–6 T). Magnetic susceptibility was measured at both 0.2 and 1 T in the temperature range 6–300 K. Mössbauer parameters δ=0.40 mm/s and ΔE=1.39 mm/s at 4.2 K, and the high temperature susceptibility Neff=6 at 300 K indicated high spin iron, but no simple spin Hamiltonian would reproduce the rapid decrease of Neff below 50 K. We interpret the data by assuming a zero field splitting D=12 cm−1 and invoking an antiferromagnetic exchange interaction J=−0.8 cm−1 between the five-coordinate iron atoms of closely spaced face-to-face heme pairs in the crystal. Slow spin relaxation at low temperature permits observation of level crossing and confirms the interpretation. It also permits the detection, through low field Mössbauer measurements, of a small rhombic distortion with E=0.024 cm−1. Mössbauer spectra of the same compound but as a dibromomethane solvate, [Fe(OEP)(2-MeHIm)]ClO4 ⋅ CH2Br2, yield generally similar parameter values, but suggest a slightly larger coupling, J=−0.85 cm−1, consistent with the fact that the paired iron atoms are known to be closer in this material.
    Type of Medium: Electronic Resource
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  • 3
    Electronic Resource
    Electronic Resource
    [S.l.] : American Institute of Physics (AIP)
    Journal of Applied Physics 64 (1988), S. 1781-1784 
    ISSN: 1089-7550
    Source: AIP Digital Archive
    Topics: Physics
    Notes: The values of the effective scattering angle 〈θ〉 of a relativistic electron beam injected through an anode foil are analyzed by different methods in the light of reported values for various beam-plasma heating experiments. Wide variations in calculated 〈θ〉 are noted depending on the method used. It is argued that the 〈θ2〉1/2 expression corrected for Molière screening and the (1/e) equivalent from the Monte Carlo code give nearly the same average scattering angle and one of them should be used to determine 〈θ〉. It is also seen that a small variation in 〈θ〉 alters significantly the plasma temperature estimate.
    Type of Medium: Electronic Resource
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  • 4
    Electronic Resource
    Electronic Resource
    [S.l.] : American Institute of Physics (AIP)
    Journal of Applied Physics 79 (1996), S. 619-624 
    ISSN: 1089-7550
    Source: AIP Digital Archive
    Topics: Physics
    Notes: The fraction of neonlike ions and the average ionic charge state in laser plasmas formed at the surface of the solid targets of germanium, selenium, and krypton have been obtained at several electron temperatures using the steady-state collisional radiative ionization model. Dielectronic recombination has been considered. The effect of consideration of dielectronic recombination of ions of one or more charge states on these parameters has been studied. It is observed that the values of electron temperature corresponding to the maximum abundance of neonlike ions in different cases of dielectronic recombination are significantly different from those obtained without consideration of dielectronic recombination. The optimum electron temperature of the plasma is estimated from the maximization of the x-ray laser gain through temperature-dependent variables of the gain coefficient and is observed to be the electron temperature at which the abundance of neonlike ions is maximum. © 1996 American Institute of Physics.
    Type of Medium: Electronic Resource
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  • 5
    Electronic Resource
    Electronic Resource
    Oxford, UK : Blackwell Publishing Ltd
    Clinical and experimental pharmacology and physiology 12 (1985), S. 0 
    ISSN: 1440-1681
    Source: Blackwell Publishing Journal Backfiles 1879-2005
    Topics: Medicine
    Notes: 1. Anti-ulcer and sedative effects of tranquillosedatives viz. benzodiazepines (diazepam, oxazepam and nitrazepam), barbiturate (phenobarbitone), phenothiazines (chlorpromazine, trifluoperazine and thioridazine) and butyrophenone (haloperidol) were compared in albino rats.2. Ulceration of the glandular stomach was induced by 2 h restraint at 4°C. Sedation was measured using the rotarod test.3. These tranquillosedatives showed dose dependent anti-ulcer and sedative effects. The relative potency and therapeutic index (ratio between rotarod ED50 and anti-ulcer ED50) of each drug were determined. Diazepam showed the highest therapeutic index (1.88).4. Diazepam significantly reduced the volume of gastric secretion, raised its pH and prevented the gastric ulcer formation in pylorus ligated rats but failed to prevent the acute duodenal ulceration induced by intramuscular injection of histamine or carbachol in guinea-pigs and rats, respectively.5. These observations suggest that benzodiazepines (diazepam) are more suitable anti-ulcer agents compared to barbiturate, phenothiazines and butyrophenone. The anti-ulcer effect of diazepam is possibly due to a combination of sedative, anti-anxiety and antisecretory actions.
    Type of Medium: Electronic Resource
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  • 6
    Electronic Resource
    Electronic Resource
    Oxford, UK : Blackwell Publishing Ltd
    Clinical and experimental pharmacology and physiology 15 (1988), S. 0 
    ISSN: 1440-1681
    Source: Blackwell Publishing Journal Backfiles 1879-2005
    Topics: Medicine
    Notes: 1. The role of putative neurotransmitters was investigated in morphine-induced Straub reaction (SR) in albino mice.2. Apomorphine (15 mg/kg) was also effective in inducing SR. However, in a smaller dose (0.2 mg/kg) it blocked SR induced by morphine.3. Morphine-induced SR was potentiated by tranylcypromine, reserpine (acute effect), imipramine and l-dopa and blocked by reserpine (chronic effect), α-methyldopa, pimozide, chlorpromazine, haloperidol and metoclopramide. Prazosin and clonidine partially blocked morphine SR in high doses.4. Propranolol, yohimbine, cyproheptadine and atropine were ineffective in blocking morphine SR.5. The results indicate that morphine SR is mediated through release of DA in the CNS which excites central D2 receptors. Activation of central α1-adrenoceptors might also play a minor role.
    Type of Medium: Electronic Resource
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  • 7
    Electronic Resource
    Electronic Resource
    [S.l.] : American Institute of Physics (AIP)
    Journal of Applied Physics 77 (1995), S. 2287-2290 
    ISSN: 1089-7550
    Source: AIP Digital Archive
    Topics: Physics
    Notes: X-ray laser gain in laser-produced plasmas for collisionally pumped 3p-3s transitions in neon (Ne)-like krypton ions has been estimated. The dependence of the gain on the temperature-dependent average ionic charge state Z¯(Te) and the fraction δ(Te) of Ne-like ions evaluated by using the plasma ionization model has been studied. It is observed that the temperature dependence of these parameters has a profound effect on the gain estimate, showing the importance of including the ionization model precisely for accurate modeling of x-ray laser gain. © 1995 American Institute of Physics.
    Type of Medium: Electronic Resource
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  • 8
    Electronic Resource
    Electronic Resource
    [S.l.] : American Institute of Physics (AIP)
    Physics of Plasmas 5 (1998), S. 1215-1217 
    ISSN: 1089-7674
    Source: AIP Digital Archive
    Topics: Physics
    Type of Medium: Electronic Resource
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  • 9
    Electronic Resource
    Electronic Resource
    [S.l.] : American Institute of Physics (AIP)
    Physics of Plasmas 5 (1998), S. 2252-2256 
    ISSN: 1089-7674
    Source: AIP Digital Archive
    Topics: Physics
    Notes: Accounting for both the long- and short-wavelength density gratings by considering the polarizations of all four electromagnetic waves parallel to each other and a finite tilt angle between the signal and pump waves, the steady-state phase conjugation in the low reflectivity regime by nearly degenerate four-wave mixing in a homogeneous plasma is investigated. The response of the density gratings caused by the beating of the signal and pump waves is considered from the theory of stimulated Brillouin scattering in a two-component plasma. The expression for the power reflectivity of the conjugate wave for the arbitrary difference frequency between the signal and pump waves and that for resonant four-wave mixing are obtained. Numerical results have been discussed in light of the experiment reported in the literature. It is noted that the measured values of the difference frequency corresponding to either density grating resonance, and the corresponding maximum reflectivity of the conjugate wave, provide a diagnostic tool for the electron temperature and the electron–ion temperature ratio, respectively. © 1998 American Institute of Physics.
    Type of Medium: Electronic Resource
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  • 10
    Electronic Resource
    Electronic Resource
    [S.l.] : American Institute of Physics (AIP)
    Physics of Plasmas 4 (1997), S. 2653-2657 
    ISSN: 1089-7674
    Source: AIP Digital Archive
    Topics: Physics
    Notes: Convective stimulated Brillouin scattering (SBS) in the directly backward direction of the obliquely incident laser light in an expanding and inhomogeneous laser plasma is studied. Accounting for the thermal motion of both electrons and ions of the plasma in the dispersion relation of the ion-acoustic wave, the expression of the convective SBS gain coefficient is derived in the weak coupling limit. The behavior of the gain with the angle of incidence of the laser irradiation in a laser-produced CH plasma is investigated by considering various plasma and laser conditions in light of the reported laser-plasma experiment with the 0.35 μm laser irradiating the CH target. The results are observed to be significantly different from those for normal incidence. © 1997 American Institute of Physics.
    Type of Medium: Electronic Resource
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