[en] The present discussion of recent studies concerning cometary composition gives attention to the results obtained by in situ measurements of Comet Halley's dust composition by Vega 1's impact mass spectrometer, which discovered a mineral fraction that appears to be CI chondritic, as well as an organic fraction consisting of highly unsaturated hydrocarbons. The mineral fraction of comets appears to form a core that is embedded in essentially organic material; the spectroscopic invisibility of carbon is due to its presence in the cometary dust. The mass of most dust particles is found to be in the 10 to the -12th to 10 to the -14th g range. A considerable fraction of the dust grains serves as an extended source of gas in the inner coma

[en] In time-of-flight mass spectrometry the mass resolution can be improved by the use of energy focusing electric fields. Calculations on the design of a third order energy focusing instrument have been performed. (orig.)

[en] By heating of well ground mixtures of the binary oxides [A₂O, Li₂O, V₂O₅, A:Li:V = 2.2:1.1:1.0 ( A = Rb, Cs); Ni-tube, 750 ⁰C, 25 d] we obtained Rb₂[LiVO₄] and Cs₂[LiVO₄] colourless, orthorhombic single crystals. We found a new type of 'Lithovanadate'-structure: space group Cmc2₁; a = 587.9(1), b = 1170.1(1), c = 793.3(1) pm, Z = 4 (A = Rb) bzw. a = 610.5(1), b = 1222.6(3), c = 815.5(2) pm, Z = 4 (A = Cs). The structure was determined by four-circle diffractometer data [MoKα-bar-radiation: 997 from 1157 I₀(hkl), R = 7.75%, R_w = 5.54% (A = Rb); 686 from 686 I₀(hkl), R = 6.97%, R_w = 4.20% (A = Cs)] parameters. The Madelung part of Lattice Energy, MAPLE, and Effective Coordination Numbers, ECoN, these via Mean Fictive Ionic Radii, MEFIR, have been calculated. (author)

[en] For calibration of the ion multiplier at the PIA instrument a pulsed ion source is needed. This can be done by electric pulse induced desorption (EPID). There ions are emitted from a coated tungsten wire, when a condensor is discharged through the wire within several nanoseconds. First tests have shown similar ion types as known from other methods by fast dissipation of energy in matter. (orig.)

[en] By heating of well ground mixtures of the binary oxides [K₂O, Li₂O, V₂O₅, K:Li:V = 2.2:1.1:1.0; Ni-tube, 900 ⁰C, 46 d] colourless monoclinic single crystals of K₂[LiVO₄] have been prepared for the first time: space group C2/m; a = 835.7(1) pm, b = 774.5(1) pm, c = 753.3(1) pm, β = 90.23(1)⁰. The structure was determined by four-circle diffractometer data [MoKα, 1018 from 1262 I₀(hkl), R = 8.65%, R_w = 5.67%]. The Madelung Part of Lattice Energy, MAPLE, and Effective Coordination Numbers, ECoN, these via Mean Fictive Ionic Radii, MEFIR, have been calculated. (author)

No abstract available

[en] Onboard the Halley Fly-By spacecrafts Vega 1, Vega 2, and Giotto were the dust impact mass spectrometers PUMA 1, PUMA 2, and PIA respectively. PUMA 1 was the most sensitive instrument among them. From its data the occurrence of masslines greater than 60 Daltons could be shown to be statistically significant. An analysis of these masslines lead to a scenario, which could explain the masslines as fragment ions from larger molecules which characterize the chemical nature of cometary organic matter as: (1) highly unsaturated hydrocarbons; (2) some of them containing oxygen; (3) less containing nitrogen; and (4) a few containing oxygen and nitrogen as heteroatoms. From the properties of the spectrometer, also some physical parameters of the dust particles could be inferred, such as their density and structure

[en] First results obtained with the MPI supported laboratory setup of a long distance time-of-flight mass-spectrometer confirm the applicability of the method to use laser-ionisation for remote analysis of small celestial bodies. After ratification of the treaty on Soviet-German cooperation in science, a grant by the BMFT enables us to participate in the LIMA-D flight instrument. We have now improved the operating system for the instrument and the data collection algorithm. In the laboratory we set up a unit to check the response of a multiplier system to complex input currents as they occur e.g. in the case of a mass spectrum. As laser-ionisation is a highly non-linear process, where ion yields depend on a lot of parameters, an extensive laboratory study, in which we cooperate with colleagues from IKI in Moscow, FMI in Helsinki, and the University of Kaiserslautern, shall give actual ion yields and ion energies for the range of laser and focus conditions used in the PHOBOS flyby configuration. These data shall be available when the flyby takes place in December 1989. (orig.)

[en] The proposal for CoMA, a pulsed time-of-flight SIMS instrument to be flown onboard CRAF to rendezvous with a comet, had been accepted by NASA in October 1986. After several attempts it seems that funding by BMFT for the instrument pre-development phase can be obtained. Apart from that we made first essential progress in producing the primary ion pulses from an indium liquid metal ion source. Those pulses are needed to operate CoMA. (orig.)

[en] This article reports on the palliative and the adjuvant system therapy of breast carcinoma, taking into consideration recent criteria of judgment and prognoses. The position of radiotherapy of metastased breast cancer is especially dealt with. Some case examples are shown. (orig.)