Comparative determination of free and combined sulphites in foods by the modified rankine method and flame photometric detection gas chromatography. V.

Summary Application of the modified Rankine (MR), GLC and present official Monier-Williams methods to the determination of sulphites in a variety of foods was attempted. Generally, sulphite contents determined by these three methods were in good agreement although the values obtained by the modified Monier-Wiliams method were slightly higher than by the other two. A marked interfering effect of other sulphur compounds was observed in the case of determinations by the Monier-Williams method. On the other hand, the determined sulphite values by the MR and GLC methods were independent of the coexisting sulphur compounds. The ratios of free or combined sulphites to total sulphites were compared among the two methods, and in most foods tested the rations of combined to total sulphites were not less than 65%. We conclude that both the MR and GLC methods are valid for the separate determination of free and combined sulphites in most foods, and these two methods will be preferred for routine analysis because of their simplicity and speed.

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Vergleichende Bestimmungen der freien und gebundenen Sulphite in Lebensmitteln mittels der modifizierten Rankinemethode und der Gaschromatographie mit Flammenphotometer-Detektor. V.

Zusammenfassung Es wurde eine vergleichende Sulfitbestimmung in verschiedenen Lebensmitteln mit Hilfe der modifizierten Rankinemethode (MR), der Gaschromatographie und der Monier-Williams-Methode durchgeführt. Die Ergebnisse stimmen gut überein, wobei die Monier-Williams-Methode geringfügig höhere Werte erbrachte. Diese Methode wird durch schwefelhaltige Lebensmittelinhaltsstoffe empfindlich gestört.Des weiteren wurde in verschiedenen Lebensmitteln die Relation von freiem zu gebundenem Sulfit ermittelt. Dabei stellte sich heraus, daß in den meisten Lebensmitteln 65% des Sulfits in gebundener Form vorliegen. Sowohl MR-Methode als auch Gaschromatographie erlauben eine getrennte Bestimmung von freiem und gebundenem Sulfit. Da beide Methoden einfach und schnell durchzuführen sind, eignen sie sich für die Routinebestimmung.

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Studies on the Analyses of Sulphites in Foods (V).     

Isolation and properties of sulphur trioxide-sulpholane complex

The one to one complex of sulphur trioxide (SO₃) and sulpholane was isolated as white needles, and the melting point, distillability, thermal stability, Raman and n.m.r. spectra were measured. It has been shown in the sulphonation of naphthalene by SO₃ in 1,2-dichloroethane that sulpholane retards the reaction far less than dioxane and rather increases selectivity for α-sulphonation.     

Hepatic protein synthesis rate of liver specimens as a predictor of viability in rat cold ischemia liver transplantation model

BACKGROUND/AIMS: We have previously reported that the hepatic protein synthesis rate, calculated as the uptake rate of L-[4.5 3H] leucine by the protein fraction during a 10-min incubation of a 16-G needle biopsy specimen of liver tissue, represents a high level of liver function and is therefore useful for evaluating liver function. We investigated the hepatic protein synthesis rate level in a pre-transplant liver to learn if it might predict the outcome in a rat orthotopic liver transplantation model. METHODS: Grafts were stored, liver specimens were obtained using a 21-G Chiba type II skinny needle, and the hepatic protein synthesis rate was calculated. Subsequently, liver transplantation was performed, and the hepatic protein synthesis rate level of revascularized liver, tissue blood flow rate, serum alanine aminotransferase, lactate dehydrogenase, hyaluronic acid, ketone body rate, and 2-week survival were examined. RESULTS: The hepatic protein synthesis rate of pretransplant liver was correlated with parameters of post-transplant liver function: hepatic protein synthesis rate of the revascularized liver (r=0.92, p<0.0001), tissue blood flow rate (r=0.77, p<0.004), serum alanine aminotransferase (r=-0.69, p<0.003), lactate dehydrogenase (r=-0.54, p<0.03), hyaluronic acid (r=-0.86, p<0.0002), and ketone body rate (r=0.57, p<0.02). Pretransplant hepatic protein synthesis rate in survivors was 263.6+/-54.2 nmol/mg protein/10 min, while that in nonsurvivors was significantly lower at 162.0+/-39.0 (p<0.0001). When evaluation was made using a logistic regression model, the accuracy predicted using the value of hepatic protein synthesis rate was 95% (19/20). CONCLUSIONS: These results suggest that measuring the hepatic protein synthesis rate of the grafts with a 21-G Chiba type II skinny needle may be a predictive criterion in the assessment of graft viability.     

3D IMAGING OF INVERTED DOMAIN STRUCTURES BY CONFOCAL SHG INTERFERENCE MICROSCOPE

ABSTRACT

A novel nonlinear optical interference microscope which enables us to take 3D images of ferroelectric domain structures is developed. This microscope is of a transmission type equipped with the confocal optical system, and exploits, as a probe, second harmonic waves generated in a sample by an incident laser beam. We apply the microscope to the observation of periodically poled domain structure in a LiTaO₃ quasi-phase matching device.     

High-field dielectric properties of polypropylene films in high-temperature region

Nonpolar polymers are used widely as electrical insulation materials, and their operating conditions sometimes become high-electric field and high temperature. Under these conditions, the conduction loss is assumed to affect the dielectric properties and to make the ac dissipation factor (tan δ) increase. Therefore the high-field dielectric properties of polymeric materials in the high-temperature region become very important. This paper describes the high-field dielectric properties of polypropylene films measured at 50 and 400 Hz above room temperature with the new electrodes developed by authors. At low temperature, the high-field tan δ is independent of the frequency of the applied field. However, at high-temperature, the high-field tan δ becomes almost inversely proportional to the frequency, namely, the conductivity is independent of the frequency. The theoretical analysis shows that the high-field dielectric loss is governed by two processes: one is the loss which appears only under ac field; and the other is conduction loss which appears also under dc field. The latter loss becomes prominent under high-electric field at high temperature.     

Structure and reactivity of MoO3-MgO catalysts

Surface of OH groups on reduced MoO₂-MgO catalysts such as $$ - - Mg - - O - - \begin{array}{*{20}c} {||} \\ {Mo} \\ | \\ \end{array} - - OH$$ may act as an active site for hydrogenation of propene. The surface hexa-coordinated Mo⁵⁺ ion (MO _6c ⁵⁺ ) was reduced to a lower number of cation such as Mo⁴⁺ or Mo³⁺ which act as an active site for metathesis of propene.     

Thiobarbituric acid-reactive substances from peroxidized lipids

The thiobarbituric acid (TBA) reaction was performed on linoleic acid 13-monohydroperoxide, autoxidized fatty esters, edible fats and oils, rat liver microsomal lipids, and on human erythrocyte ghost lipids in order to determine which substances from peroxidized lipids are TBA-reactive. The reaction was carried out in 2% acetic acid containing butylated hydroxytoluene using two different reaction modes: a one-step mode which involves heating at 100°C, and a two-step mode which involves first treatment at 5°C and subsequent heating at 100°C. Yields of the red 1∶2 malonaldehyde/TBA adduct, as estimated by absorbance, fluorescence intensity and high-performance liquid chromatography, were much higher than the malonaldehyde content as determined by direct chemical analysis. Yields of red pigment obtained by the two-step mode were slightly higher than those obtained by the one-step mode. Pigment yields were dramatically increased by addition oft-butyl hydroperoxide. Red pigment formation from alkenals and alkadienals was similarly enhanced by the two-step mode or by addition oft-butyl hydroperoxide, whereas pigment formation from malonaldehyde was not. It appears likely that a component of the total red pigment formed from the peroxidized lipids was due to aldehyde species other than malonaldehyde.     

Relationship between familiarity and humanness of robots – quantification of psychological impressions toward humanoid robots

We investigate the relationships between familiarity and humanness of humanoids from psychological perspective of view. Two thousand six hundred and twenty-four people from their 10s to 70s in Japan evaluated familiarity and humanness of different 11 humanoids based on the psychological scales which are developed for evaluation of humanoids. Results showed that robot-like robots which have round shapes are evaluated higher in familiarity and lower in humanness than robot-like robots which have mechanic appearance. Androids which have totally human-like appearances are evaluated higher in humanness and familiarity than robots which are partly human-like, while one android was rated high in humanness but low in familiarity. Relatedly, repulsion which reflects a value toward the existence of humanoids bears a proportionate relationship to humanness. Higher humanness with humanoids related to higher repulsion. In sum, the relationship between familiarity and humanness is curvilinear, while repulsion and humanness shows a linear relationship. We discussed the importance of appearance of robots and interaction with robots to introduce robots toward ordinary people.