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1998[X]
61Author    Naohiro Yoshida, Noriko Onoda-Yamamuro, Shin'. Ichi Ishimaru, Keizo Horiuchi, Ryuichi IkedaRequires cookie*
 Title    Temperature Dependence of 2 H Quadrupole Coupling Constants in 2 H 2 0 and Ionic Motions in Crystalline IM( 2 H 2 0) 6 ] ISnCl 6 ] (M: Mg, Ca), Studied by 2 H NMR and Neutron Powder Diffraction  
 Abstract    The temperature dependence of 2 H NMR spectra was measured at 130-430 K on [M(D 2 0) 6 ] [SnCl 6 ] (M : Mg, Ca) (rhombohedral, space group: R3), and neutron powder diffraction on the Mg salt was performed at room temperature. Based on the accurate orientation of D 2 0 molecules in an octahedral cation, spectra with a large asymmetry parameter rj, observed around 200 K, were explained by a model of 180° flip of water molecules. Another motional narrowing observed above room temperature was assigned to a cationic overall reorientation about the C 3 -axis. 
  Reference    Z. Naturforsch. 53a, 473—479 (1998); received October 31 1997 
  Published    1998 
  Keywords    2 H NMR, Neutron Diffraction, Molecular Motion, Quadrupole Coupling Constant, Spectrum Lineshape 
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 TEI-XML for    default:Reihe_A/53/ZNA-1998-53a-0473.pdf 
 Identifier    ZNA-1998-53a-0473 
 Volume    53 
62Author    Maria Zdanowska-FnjczekRequires cookie*
 Title    NQR Relaxation Studies on Halogenomethyl Groups in Halogenoacetates  
 Abstract    The effect of temperature on the chlorine NQR spin-lattice relaxation times in CSH(C1H 2 -CCOO) 2 , KH(CL 3 CCOO) 2 and N(CH 3) 4 H(C1F 2 CC00) 2 has been studied in the temperature rang'e 77 K to room temperature. The results were discussed on the basis of NQR relaxation theory. 
  Reference    Z. Naturforsch. 53a, 480—483 (1998); received March 4 1998 
  Published    1998 
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 TEI-XML for    default:Reihe_A/53/ZNA-1998-53a-0480.pdf 
 Identifier    ZNA-1998-53a-0480 
 Volume    53 
63Author    Maria Zdanowska-Fnjczek, Malgorzata Grottel, Ryszard JakubasRequires cookie*
 Title    C1 NQR and l H NMR Studies of Molecular Motions in Guanidinium Salt of Chloroacetic Acid  
 Abstract    Multinuclear NQR and NMR techniques have been applied in order to study the molecular dynamics in [C(NH 2) 3 ](ClH 2 CCOO). The 35 C1 NQR frequency was measured over a wide range of temperature. The experimental results were described by using the theories of Bayer and Brown which take into account the torsional oscillations of the CClH 2 -group of the anion. A study of the proton NMR second moment as well as relaxation times T, and T Xp performed in a wide temperature range revealed an onset of the guanidinium cation reorientation around its two-fold symmetry axis. Activation parameters for this motion were determined. 
  Reference    Z. Naturforsch. 53a, 484—487 (1998); received March 24 1998 
  Published    1998 
  Keywords    NMR, NQR, Molecular Motion 
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 TEI-XML for    default:Reihe_A/53/ZNA-1998-53a-0484.pdf 
 Identifier    ZNA-1998-53a-0484 
 Volume    53 
64Author    Detlef BrinkmannRequires cookie*
 Title    Spin Gap, Electronic Crossover, and Charge Density Waves in Y-Ba-Cu-O Superconductors  
 Abstract    This paper discusses recent NQR/NMR studies performed on Y-Ba-Cu-0 superconductors at the Uni-versity of Zürich. The work is concerned with normal state properties which are still controversial, for instance the spin-gap effect, i.e. the opening of a pseudo gap in the electron spin excitation spectrum at a temperature 7*, which lies above T c . We will report on the detection of "anomalies" which are dis-played in the temperature dependence of several NMR and NQR quantities measured in the normal state of YBa 2 Cu 4 0 8 . These anomalies are interpreted as an electronic crossover which involves a charge re-distribution in the Cu0 2 planes and an enhancement of the charge fluctuations. As a possible mecha-nism of the crossover, a charge density wave instability is proposed. 
  Reference    Z. Naturforsch. 53a, 488—491 (1998); received December 30 1997 
  Published    1998 
  Keywords    NQR, NMR, High-Temperature Superconductors, Spin gap Electronic Crossover 
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 TEI-XML for    default:Reihe_A/53/ZNA-1998-53a-0488.pdf 
 Identifier    ZNA-1998-53a-0488 
 Volume    53 
65Author    M. Carbucicchio, G. Palombarini, M. RateoRequires cookie*
 Title    Hyperfine Interactions of 57 Fe Nuclei in the Study of Interdiffusion Phenomena and Phase Formation  
 Abstract    The effects of interdiffusion phenomena and reactions occurring in the early stages of the interaction at 1273 K between iron and chromium monoborides were studied by transmission Mössbauer and X-ray diffraction techniques, and modifications occurring in Fe/Al multilayers during both deposition and subsequent thermal aging at 400 K in vacuum or air were studied by conversion electron Mössbauer and Auger electron depth profiling techniques. In both cases the main objective of the work was to obtain a better understanding of the mechanisms of modification of the materials under examination with a view towards improving the properties of materials and coatings for specific applications. 
  Reference    Z. Naturforsch. 53a, 492—500 (1998); received January 26 1998 
  Published    1998 
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 TEI-XML for    default:Reihe_A/53/ZNA-1998-53a-0492.pdf 
 Identifier    ZNA-1998-53a-0492 
 Volume    53 
66Author    G. J. Hill, J. M. Keartland, M.J R HochRequires cookie*
 Title    Pressure Dependence of the EFG in Semimetallic Arsenic and Antimony  
 Abstract    The pressure variation of the axial EFG at the ion sites in semimetallic arsenic and antimony, at am-bient temperature, has been investigated using pulsed NQR. A weakly nonlinear decrease of the EFG is observed in both systems. The data are analyzed in terms of the lattice contribution to the EFG, which involves a lattice of point monopoles immersed in a uniform, compensating, background charge. The pressure dependence of the EFG obtained from the present measurements is far weaker than the pres-sure dependence of the calculated lattice contribution. Our results support previous suggestions that va-lence effects are important in determining the EFG in these semimetals. 
  Reference    Z. Naturforsch. 53a, 501—503 (1998); received March 24 1998 
  Published    1998 
  Keywords    EFG, NQR, Arsenic, Antimony, Pressure 
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 TEI-XML for    default:Reihe_A/53/ZNA-1998-53a-0501.pdf 
 Identifier    ZNA-1998-53a-0501 
 Volume    53 
67Author    E. A. Kravchenko, V. G. Orlov, SuanHai Fam, YuF. KarginRequires cookie*
 Title    Bi NQR and Magnetic Properties of Bismuth Oxide-Based Compounds  
 Abstract    The NQR line shapes of 209 Bi in the a-Bi 2 0 3 -based mixed oxides Bi 2 0 3 • 2M 2 0 3 (M = Al, Ga). Bi 2 0 3 • 3Ge0 2 , and 2Bi 2 0 3 • 3Ge0 2 are recorded in zero and weak magnetic fields (// ext < 500 Oe) and compared with the results of computer simulation. Splittings and line shape asymmetry, exhibited by the resonances, suggest that internal magnetic fields, similar to those earlier reported for a-Bi 2 0 3 and Bi 3 0 4 Br, may exist in these compounds. In the spectra of single crystal Bi 4 Ge 3 0 12 , the line multiplicity in external magnetic fields is higher than simulated, which might results from domains in the crystal. In external magnetic fields a notable increase in the line intensity was observed, the effect depend-ing on the mutual orientation of the EFG axes and the fields perturbing the nuclear spin system. 
  Reference    Z. Naturforsch. 53a, 504—513 (1998); received January 26 1998 
  Published    1998 
  Keywords    209 Bi NQR, Internal Magnetic Field, Line Shape, Applied Magnetic Field, Computer Simulation 
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 TEI-XML for    default:Reihe_A/53/ZNA-1998-53a-0504.pdf 
 Identifier    ZNA-1998-53a-0504 
 Volume    53 
68Author    Yoshio Kume, Tetsuo AsajiRequires cookie*
 Title    Chlorine-35 NQR Study of a Structural Phase Transition in (ND 4 ) 2 PdCV  
 Abstract    Temperature dependences of 35 C1 NQR frequencies and spin-lattice relaxation times were measured at 4.2 to 400 K for natural and deuterated ammonium hexachloropalladate. It was confirmed that only the deuterated salt undergoes a first order phase transition at 30 K. The crystal structure of the low-tem-perature phase is predicted to be the same as that of the deuterated ammonium hexachloroplatinate and hexachloroplumbate. The mechanism of the deuteration-induced phase transition is discussed. 
  Reference    Z. Naturforsch. 53a, 514—517 (1998); received March 24 1998 
  Published    1998 
  Keywords    Isotope Effect, Phase Transition, Chlorine NQR, Spin-lattice Relaxation, Deuterated Ammonium Hexachloropalladate 
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 TEI-XML for    default:Reihe_A/53/ZNA-1998-53a-0514.pdf 
 Identifier    ZNA-1998-53a-0514 
 Volume    53 
69Author    Haruo Niki, Kikuhiro Kano, Mitsuhiro Takase, Kensei Majikina, Katsuma Yagasaki, Takeshi Shinohara, Mamoru Omori, Shoichi Tomiyoshi, Etsuo AkibaRequires cookie*
 Title    Oxygen Content Dependence of 63 Cu(l) NQR and Proton NMR in Hydrogen-Doped Antiferromagnetic YBa 2 Cu 3 0 6+A: H y  
 Abstract    The oxygen content dependence of 63 Cu NQR at the Cu(l) site and proton NMR have been meas-ured in the antiferromagnetic phase of powdered samples of hydrogen-doped YBa 2 Cu 3 0 6+x .H v (0.07 < JC < 0.17 and y » 1) from 4.2 to 90 K. The spectrum of 1 H NMR is a single line and the line width increases below 15 Kdue to magnetic interactions. The enhancements of Tf 1 and 7^ 1 of 63 Cu(l)NQR occur around 35 and 15 K, respectively. These enhancements increase with increasing oxygen concen-tration. The maximum values of Tf 1 and T^ for the sample with x = 0.17 reach 200 sec -1 and more than 7 msec -1 , respectively. The predominant source for the relaxation mechanism of 63 Cu(l) NQR and the line broadening of 'H NMR are found to be the fluctuating magnetic field due to the staggered Cu 2+ moments. 
  Reference    Z. Naturforsch. 53a, 518—523 (1998); received March 24 1998 
  Published    1998 
  Keywords    Antiferromagnetic materials, High-T^ superconductor, Spin-lattice Relaxation Time, Cu NQR, Proton NMR 
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 TEI-XML for    default:Reihe_A/53/ZNA-1998-53a-0518.pdf 
 Identifier    ZNA-1998-53a-0518 
 Volume    53 
70Author    H. Nishihara, T. Kanomata, K. Sato, N. Suzuki, T. HaradaRequires cookie*
 Title    NMR of 51 V in VRuP: Possible Onset of Charge-Density-Waves  
 Abstract    NMR experiments are reported for VRuP which has an orthorhombic TiNiSi structure and shows anomalies in the temperature dependence of the electric conductivity and static susceptibility. A field-swept spectrum of 5 'V perturbed by a quadrupole interaction has been observed, which shows no anomalous temperature dependence. However, the metallic spin-lattice relaxation rate decreases in a stepwise fashion with decreasing temperature at around 200 K, in accordance with the resistivity and the susceptibility data, suggesting a possible CDW formation in this material. 
  Reference    Z. Naturforsch. 53a, 524—527 (1998); received January 26 1998 
  Published    1998 
  Keywords    NMR, CDW, VRuP, 51 V, Spin-Lattice Relaxation 
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 TEI-XML for    default:Reihe_A/53/ZNA-1998-53a-0524.pdf 
 Identifier    ZNA-1998-53a-0524 
 Volume    53 
71Author    A. M. Petrosyan, S. S. Terzyan, V. M. Burbelo, R. P. SukiasyanRequires cookie*
 Title    Investigation of Some New Nonlinear Optical Crystals by Means of NQR, IR and X-Ray Diffraction Methods  
 Abstract    Some new analogues of the nonlinear optical crystal L-arginine phosphate monohydrate (LAP) (Arg • HI0 3 , Arg • 2HI0 3 , Lys • HI0 3 , Lys • 2HI0 3 , Lys • 3HI0 3 , Bet • 3HI0 3) were obtained and in-vestigated by means of IR, NQR, X-ray diffraction and SHG methods. The importance of this class of crystals for revealing new nonlinear optical crystals is pointed out. 
  Reference    Z. Naturforsch. 53a, 528—536 (1998); received January 26 1998 
  Published    1998 
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 TEI-XML for    default:Reihe_A/53/ZNA-1998-53a-0528.pdf 
 Identifier    ZNA-1998-53a-0528 
 Volume    53 
72Author    J. Pirnat, Z. Trontelj, H. BorrmannRequires cookie*
 Title    NQR View of Solid Phases of NOC1*'*  
 Abstract    Chlorine NQR studies of solid nitrosyl chloride NOC1 between 110 and 212 K are reported. In the temperature dependence an order-disorder phase transition near 145 K, found by X-ray diffraction, is confirmed. Unusual hysteretic NQR signal behaviour indirectly proves also the low temperature phase transition below 100 K. In the measured temperature region fast relaxing mechanisms are present. The upper limit of the expected 14 N NQR frequency is estimated using the Townes-Dailey approach. 
  Reference    Z. Naturforsch. 53a, 537—541 (1998); received March 24 1998 
  Published    1998 
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 TEI-XML for    default:Reihe_A/53/ZNA-1998-53a-0537.pdf 
 Identifier    ZNA-1998-53a-0537 
 Volume    53 
73Author    YaA. Ossipyan, N. S. Sidorov, V. I. Kulakov, V. L. Matukhin, A. I. Pogoreltsev, V. N. Anashkin, I. A. Safin, L. E. MatukhinaRequires cookie*
 Title    NQR Studies of Halogen Treated 1-2-3 System  
 Abstract    NQR spectra of copper in polycrystalline samples of iodine treated RBa 2 Cu 3 O y (R = Y, Gd) were studied. The results of all the experiments show evidence for the modifications occurring in the oxygen sublattice in treated compounds. 
  Reference    Z. Naturforsch. 53a, 542—545 (1998); received March 24 1998 
  Published    1998 
  Keywords    NQR-spectra, Superconductors, Treatment, Halogens, Diffusion 
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 TEI-XML for    default:Reihe_A/53/ZNA-1998-53a-0542.pdf 
 Identifier    ZNA-1998-53a-0542 
 Volume    53 
74Author    EvgeniiA. RomanenkoRequires cookie*
 Title    Phase Transformation and Structure of N-chlorocarbonylisocyanide Dichloride  
 Abstract    The 35 C1 nuclear quadrupole resonances in N-chlorocarbonylisocyanide dichloride show that it exists in two polymorphic forms. The metastable a phase has six 3 ~ Cl NQR lines and the stable ß phase has three. The latter is obtained irreversibly by annealing the a phase at 179 K. The temperature depen-dences of the 35 C1 NQR frequencies, spin-lattice and spin-spin relaxation times are obtained in both phases. The results of the 35 C1 NQR studies are discussed together with calculated MNDO level data and other physical properties (IR frequencies, dipole moments) of this compound. 
  Reference    Z. Naturforsch. 53a, 546—548 (1998); received May 4 1998 
  Published    1998 
  Keywords    N-Chlorocarbonylisocyanide Dichloride, Structure, Phase Transformation, 35 C1 NQR Parameters, MNDO calculation 
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 TEI-XML for    default:Reihe_A/53/ZNA-1998-53a-0546.pdf 
 Identifier    ZNA-1998-53a-0546 
 Volume    53 
75Author    K. Sato, S. Takeda, S. Fukuda, T. Minamisono, M. Tanigaki, T. Miyake, Y. Maruyama, K. Matsuta, M. Fukuda, Y. NojiriRequires cookie*
 Title    FT-NMR Detection of 45 Sc, 49 Ti and 93 Nb in Ti0 2 Single Crystal  
 Abstract    In order to determine the electric quadrupole moment of the short-lived Remitter 41 Sc from the quad-rupole coupling constant in Ti0 2 , we measured the field gradient by detecting the Fourier-Transformed-NMR of stable isotope 45 Sc doped in TiO->. Also, in order to study the electronic structure of impurities systematically, EFGs were measured for * 5 Sc, 49 Ti and 93 Nb in a Ti0 2 single crystal. 
  Reference    Z. Naturforsch. 53a, 549—551 (1998); received December 31 1997 
  Published    1998 
  Keywords    Ti0 2, 41 Sc, Quadrupole Moment, Transition Metal Impurity, Electric Field Gradient 
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 TEI-XML for    default:Reihe_A/53/ZNA-1998-53a-0549.pdf 
 Identifier    ZNA-1998-53a-0549 
 Volume    53 
76Author    Y. M. Seo, J. Pelzl, C. DimitropoulusRequires cookie*
 Title    Comparison of 35 Cl NQR Spectra between the Mixed Crystals K 2 Sn l x Re x Cl 6 and the Al 3+ Doped Crystals K 2 SnCl 6 :Al 3+ * +  
 Abstract    35 Cl Nuclear Quadrupole Resonance (NQR) has provided a valuable tool for investigating the local structure in mixed crystals K^Sm-a-RexC^ and Al 3+ doped crystals K 2 SnCl 6 :Al 3+ . The measured NQR line shapes and relaxation times of both kinds of impurity containing crystals in the cubic phase of the host K-, SnCl 6 show markedly different impurity effects; static impurity effects in K 2 Sni_ x Re :c Cl6 and dynamic effects in K 2 SnCl 6 :Al 3+ . The 35 C1 NQR spectra of K 2 SnCl 6 :Al 3+ near the transition temperature (T c) indicate the presence of pretransition of the local structure in the high temperature cubic phase. 
  Reference    Z. Naturforsch. 53a, 552—558 (1998); received March 24 1998 
  Published    1998 
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 TEI-XML for    default:Reihe_A/53/ZNA-1998-53a-0552.pdf 
 Identifier    ZNA-1998-53a-0552 
 Volume    53 
77Author    Hiromitsu Terao, Masao Hashimoto\, Tsutomu Okuda, Alarich WeissRequires cookie*
 Title    Phase Transitions and Crystal Structure of Dimethylammonium Tribromomercurate(II), (CH 3 ) 2 NH 2 HgBr 3 , as Studied by 81 Br NQR and Single Crystal X-ray Diffraction  
 Abstract    The temperature dependence of the 81 Br NQR frequencies of the title compound has revealed the presence of three phases (I, II and III, in the order of decreasing temperature): T cl (II -1) = (318 ± 10) K and T c2 (III -II) = (202 ± 1) K. The transitions were confirmed by thermal analysis (DTA). Both of the II-I and I-II transitions exhibited strong hysteresis (/. e., superheating and supercooling, respectively). The crystal data, determined by single crystal X-ray diffraction, are: monoclinic, space group P2/a, a = 1384.8(3), b = 934.7(4), c = 1452.0(2) pm, ß = 104.10(1)°, Z= 8, R = 0.076. The crystal has two crystallographically independent cations (CH 3) 2 NH 2 + and an infinite chain of anions almost in the c-direction. The anion chain is considered to consist of a HgBr 2 molecule and two different HgBr 4 2 ~ anions which are interconnected via weak intermolecular Hg-Br bonds. The splitting patterns of the 8 'Br NQR spectra indicate that rearrangements of the Hg-Br bonds are slight at the III-II transition but serious at the II-I transition. Some of the 81 Br NQR lines show anomalous temperature coefficients, attributable probably to thermal motions of cations. 
  Reference    Z. Naturforsch. 53a, 559—567 (1998); received January 26 1998 
  Published    1998 
  Keywords    (CH 3 ) 2 NH 2 HgBr 3, X-Ray Analysis, NQR, Phase Transition, Crystal Structure 
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 TEI-XML for    default:Reihe_A/53/ZNA-1998-53a-0559.pdf 
 Identifier    ZNA-1998-53a-0559 
 Volume    53 
78Author    T. H. Yeom, S. H. Choh, K. S. Hong, H. Y. Yeom, Y. H. Park, Y. M. YuRequires cookie*
 Title    Nuclear Quadrupole Interactions of 27 A1 in Alexandrite Single Crystal  
 Abstract    In an alexandrite single crystal four sets of NMR spectra for 27 A1 (7=5/2) were observed in the crystallographic ab, be, and ca planes. The AI (I) center has four magnetically inequivalent Al sites, whereas the AI (II) center has two. The nuclear quadrupole coupling constant and asymmetry parameter of A1(I) and AI (II) in an alexandrite crystal were determined. Within the experimental accuracy, our parameters turned out to have the same values as those of a chrysoberyl crystal. 
  Reference    Z. Naturforsch. 53a, 568—572 (1998); received October 31 1997 
  Published    1998 
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 TEI-XML for    default:Reihe_A/53/ZNA-1998-53a-0568.pdf 
 Identifier    ZNA-1998-53a-0568 
 Volume    53 
79Author    L. A. Zemnukhova, R. L. DavidovichRequires cookie*
 Title    Sb and 209 Bi Nuclear Quadrupole Resonance Study of Complex Compounds of Antimony(III) and Bismuth(III) in the Temperature Range 77-400 K  
 Abstract    A large number of solid fluoride and heteroligand acidocomplex compounds of antimony(III) and bismuth(III) with single and mixed cations has been prepared from aqueous solutions. Their crystal structures and 121,123 Sb and 209 Bi NQR spectra have been investigated in a wide temperature range. 
  Reference    Z. Naturforsch. 53a, 573—584 (1998); received May 4 1998 
  Published    1998 
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 TEI-XML for    default:Reihe_A/53/ZNA-1998-53a-0573.pdf 
 Identifier    ZNA-1998-53a-0573 
 Volume    53 
80Author    T. A. Babushkina, I. V. SeryukovaRequires cookie*
 Title      
 Abstract    NQR spectroscopy was used to study the intercalating influence on the iodine electric field gradient of lead(ll) and cadmium(ll) iodides. We used pyridine, piperidine, aniline and quinoline, as guest sub-stances. In the intercalates the NQR frequencies and their dependence on temperature in different crys-talline phases were studied. The peculiarities of chemical bonds and crystal structures were discussed. 
  Reference    Z. Naturforsch. 53a, 585—589 (1998); received May 4 1998 
  Published    1998 
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 TEI-XML for    default:Reihe_A/53/ZNA-1998-53a-0585.pdf 
 Identifier    ZNA-1998-53a-0585 
 Volume    53 
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