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81.
Some new heterocyclic compounds containing isoxazole, pyrazole and oxadiazole ring systems were prepared from various chalcones. The synthesized compounds have been characterized by elemental analysis and spectral methods. These compounds were screened for their antimicrobial activities.  相似文献   
82.

Lattice dynamics and electron-phonon coupling are calculated for non-magnetic hcp iron at 100 GPa by a first-principles linear response full-potential LMTO method. Superconducting transition temperature is estimated to be less than 0.5 K. For ferromagnetic bcc iron lattice dynamical calculations are performed for 9.8 GPa as well as for ambient pressure. The results of calculation reproduce well the pressure dependence of phonon dispersion curves observed by neutron scattering measurements.  相似文献   
83.
In the two-electron reduction of diphenylsulfoxide to diphenylsulfide, which is considered a model reaction of sulfite reduction catalyzed by sulfite reductase, methylviologen-pendent iron(III) porphyrin exhibits much higher catalytic activity than usual iron(III) and manganese(III) tetraphenylporphyrins, while cobalt(II) tetraphenylporphyrin exhibits much less catalytic activity than the others. Discussion about the active species and the reason of the acceleration by methylviologen-pendent is presented.  相似文献   
84.
When ohmic heating power is applied during the microwave discharge at the electron cyclotron resonance, the plasma current and density build-up become fast and the loop voltage required to start the tokamak discharge decreases. The micro-wave burst observed in the initial stage is reduced and the burst of hard X-rays, occurring at the quasi-steady stage of discharge in the case of no microwave injection, disappears, suggesting that the production of run-away electrons is suppressed strongly.  相似文献   
85.
86.
Let nq(k, d) denote the smallest value of n for which there exists an [n, k, d; q]-code. It is known (cf. (J. Combin. Inform. Syst. Sci.18, 1993, 161–191)) that (1) n3(6, 195) {294, 295}, n3(6, 194) {293, 294}, n3(6, 193) {292, 293}, n3(6, 192) {290, 291}, n3(6, 191) {289, 290}, n3(6, 165) {250, 251} and (2) there is a one-to-one correspondence between the set of all nonequivalent [294, 6, 195; 3]-codes meeting the Griesmer bound and the set of all {v2 + 2v3 + v4, v1 + 2v2 + v3; 5, 3}-minihypers, where vi = (3i − 1)/(3 − 1) for any integer i ≥ 0. The purpose of this paper is to show that (1) n3(6, 195) = 294, n3(6, 194) = 293, n3(6, 193) = 292, n3(6, 192) = 290, n3(6, 191) = 289, n3(6, 165) = 250 and (2) a [294, 6, 195; 3]-code is unique up to equivalence using a characterization of the corresponding {v2 + 2v3 + v4, v1 + 2v2 + v3; 5, 3}-minihypers.  相似文献   
87.
88.
Summary The thin-layer chromatographic behaviour of the noble metals on ECTEOLA-cellulose has been examined in HCl and aqueous chloride solutions of Li, Na, Mg, Ca, Sr and Al. The Rf-values decrease in the order Ir(III) Rh(III) > Ru(III) > Pd(II) > Pt(IV) > Ir(IV) > Au(III) in all of the media of higher chloride concentrations (3M to 5M), in which there are sufficiently large differences in Rf-values of adjacent metals to resolve them clearly. Especially, the HCl solutions with or without H2O2 are very suitable for multi-component separations of the noble metals.
DC-Trennung von Edelmetallen auf ECTEOLA-Cellulose in salzsauren und wäßrigen Chloridlösungen
Zusammenfassung Das Verhalten von Edelmetallen wurde in salzsauren Lösungen sowie in Lösungen der Chloride von Li, Na, Mg, Ca, Sr und Al geprüft. Die Rf-Werte nehmen in allen Medien mit höherer Chlorid-konzentration (3M bis 5M) in folgender Reihenfolge ab: Ir(III) Rh(III) > Ru(III) > Pd(II) > Pt(IV) > Ir(IV) > Au(III). Die Unterschiede in den Rf-Werten sind groß genug, um eine deutliche Trennung zu gewährleisten. Salzsaure Lösungen mit oder ohne H2O2-Zusatz sind besonders gut für die Trennung von Vielkomponenten-Gemischen geeignet.
  相似文献   
89.
Methyleneimine was detected in the gas phase by a moderately high resolution infrared spectrometer as one of the intermediate species produced by a pyrolysis of amines. Observed vibrational frequencies of some isotopic derivatives have been combined with the ab initio values to reach a most reliable force constants set. Some other spectroscopic parameters, involving geometrical parameters and dipole moment derivatives, have also been calculated ab initio and compared with the observation. Its half-life in our experimental apparatus was about 10 min, which is much longer than the previously reported values, 0.1 or 10 sec.  相似文献   
90.
This paper describes a software package for a personal computer which deals with storage records of radioactive wastes; the software keeps the records of purchase and use of radioisotopes and makes the inventory records of radioactive wastes. The records for the cargo booking of the wastes for the Japanese Radioisotope Association can be prepared by this software package.  相似文献   
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