THz rotational spectrum of H2F+.

In view of recent tremendous advance in astronomical observations in the submillimeter to THz region brought by the Herschel space craft, laboratory high-resolution spectroscopic investigations in that frequency region into unstable molecules, in particular, light hydride ions, are urgently needed. As a part of such endeavor, rotational transitions of H(2)F(+) were observed in the THz-region by using a tunable far-infrared spectrometer. These newly detected lines together with the submillimeter-wave lines obtained previously and the combination differences derived from infrared vibration-rotation lines were subject to a least-squares analysis that yielded a set of molecular constants with much better accuracy. The measured and predicted THz transition frequencies should prove to be a useful probe into detection of interstellar H(2)F(+).

[Ingestion and excretion of aluminum in foods and pharmaceuticals].

We measured the aluminum contents in foods and pharmaceuticals, and the aluminum concentrations in urine by atomic absorption spectrophotometry with polarized Zeeman background correction to obtain the daily intake and excretion of aluminum. The daily urinary excretions of aluminum in healthy females were obtained after consuming sea algae, hizikia fusiforme, which has a high aluminum contents. Daily aluminum excretion did not increase after taking hizikia fusiforme. On the other hand, high aluminum excretions were observed after taking an analgesic/antipyretic with a high aluminum contents, compared with the usual daily aluminum excretion (p < 0.001), and compared with after taking an analgesic/antipyretic with no aluminum (p < 0.0001). We found that the daily urinary excretion of aluminum was not related to the total consumption of aluminum, but depended on the binding state of aluminum consumed.

Far-Infrared Rotational Spectrum of ArD+

Rotational transition frequencies of ArD+ were measured with an accuracy of a few hundred kilohertz in the 0.95-4.7 THz region, using a tunable far-infrared radiation source. Effective rotational parameters B, D, and H were determined for the ground vibrational state. The observed frequencies were combined with the previous data on all isotopic species of protonated argon ion to improve the mass-independent Dunham parameters Ukl, DeltaArkl, and DeltaHkl. Copyright 1999 Academic Press.

Frequency Measurement of Pure Rotational Transitions of H217O and H218O from 0.5 to 5 THz.

Frequencies of pure rotational transitions of isotopic species of water, H217O, and H218O were measured in the 1-5 THz region with a high-precision far-infrared spectrometer using a tunable radiation source. Measured frequencies of more than 100 spectral lines for each species provide an excellent frequency standard for the far-infrared region. Molecular parameters based on a Watson-type Hamiltonian have been obtained to reproduce the observed frequencies. Copyright 1999 Academic Press.

Tunable Far-Infrared Spectroscopy of 82KrD+, 84KrD+, 86KrD+, and 82KrH+

Pure rotational spectra of isotopic species of protonated krypton 82KrD+, 84KrD+, 86KrD+, and 82KrH+ were observed in the 0.75-3.5 THz region, using a tunable far-infrared radiation source. Rotational parameters B, D, and H of these molecular ions were determined. By analyzing the observed frequencies with the previous data on all the isotopic species, the mass independent Dunham parameters Ukl, DeltaKrkl, and DeltaHkl have been improved. Copyright 1998 Academic Press.

[Aluminum contents in dried and cooked sea vegetables].

Regarding aluminum contents in sea vegetables, dried hijiki (an edible brown algae), dried wakame (seaweed) and dried konbu (kelp) contained 1.08mg/g, 17.7 to 149 micrograms/g, and 4.23 to 24.5 micrograms/g, of aluminum, respectively. With hijiki, especially, having a high aluminum content. Hijiki reconstituted by water immersion contained 450 to 678 micrograms/g, of aluminum. Thus, aluminum in dried hijiki was decreased by 40 to 66% by water immersion. The immersion water of blanched and salted wakame and fruit-bearing leaf wakame contained 4.67 to 6.92 micrograms and 1.00 microgram of aluminum, respectively. The migration ratio of aluminum was 8 approximately 12% for blanched and salted wakame and was 1% for fruit-bearing leaf wakame. The immersion water of Hidaka konbu contained 16.1 to 21.4 micrograms of aluminum, while that of Rishiri konbu contained 4.79 to 7.36 micrograms of aluminum. Thus, 22 to 57% of aluminum migrated into the konbu immersion water. Aluminum scarcely migrated into the supernatant of the immersion water. Compared with the cold water immersion method, a high aluminum migration ratio was achieved in the heat extraction method. It was estimated that the aluminum intake from reconstituted hijiki (dry weight: 5g) was about 2.2 to 3.4mg, which amounted to 50 to 75% of the daily aluminum intake of a typical Japanese diet.

[Contents of aluminum and manganese in tea leaves and tea infusions].

We measured the contents of aluminum and manganese in tea leaves and tea infusions by means of various standardized infusion conditions, and by using flameless atomic absorption spectrophotometry, and investigated the influence of infusion conditions on the elution of aluminum and manganese into the tea infusions. Furthermore, we tried to estimate the daily intake of aluminum and manganese due to drinking tea infusions. The content of aluminum in tea leaves was 1420 micrograms/g in case of wulong tea, 576 micrograms/g in black tea, and 520 micrograms/g in green tea. The content of manganese was 1440 micrograms/g in the case of wulong tea, 670 micrograms/g in green tea, and 535 micrograms/g in black tea. The concentration of aluminum in tea infusions was 1.49-5.58 micrograms/ml in wulong tea, 0.90-4.92 micrograms/ml in green tea, and 0.64-4.35 micrograms/ml in black tea. The concentration of manganese was 1.75-6.67 micrograms/ml in green tea, 0.94-4.04 micrograms/ml in wulong tea, and 0.78-3.24 micrograms/ml in black tea. The ratio of the molar concentration of aluminum to that of manganese was 1-2:1 in tea leaves, and 1-5:1 in tea infusions. In the case of elevated-temperature infusion, increases of the concentrations of aluminum and manganese in tea infusions were recognized. By repeating infusion three times according to the standard method for ingredient analysis of food, 18-29% of the total content of aluminum in tea leaves was eluted, and 12-29% of the total content of manganese was eluted.(ABSTRACT TRUNCATED AT 250 WORDS)

[Effects of sodium chloride, acetic acid and citric acid on the dissolution of aluminum from aluminum cooking utensils].

In order to investigate the effects of sodium chloride and organic acids on aluminum elution from cooking utensils made of aluminum, the quantities of aluminum elution were measured in solutions with various concentrations of sodium chloride, acetic acid and citric acid by flameless atomic adsorption spectrophotometry. The increase of the aluminum elution rate from a pudding cup, an aluminum pan and an alumite pan could be clearly distinguished by the coexistence of acetic acid or citric acid and sodium chloride. The elution was low in the presence of sodium chloride at room temperature, but it was distinctly accelerated by heating. Although alumite treatment had the effect of protection against aluminum elution, such elution obviously increased, as shown by the existence of acid and sodium chloride at high temperatures. Aluminum elution rates from surface-untreated cooking utensils made of aluminum were increased by heating by a factor of several thousand.