It is well known that the ability of gel-formation of agar aqueous solution is remarkably decreased by addition of mandarine-juice. The phenomenon has been supposed to be caused by the degradation of molecular chains of agar by acid.
X-ray studies of the phenomenon was carried out by analogy with cellulose. X-ray diffraction pattern of agar gel was changed remarkably by addition of only about 0.5% citric acid (final concentration) in 1.5% agar solution. And some part of Debye-Scherrer's rings in the X-ray diagram being vanished. The results indicate that the network of molecule was decreased by the interruption of intermolecular cohesion resulted from the acid combined with agar molecule in the plane of pyranose ring.

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In part 2 of this series were described the corrosive effects of the various solution that are generally used in cooking on aluminum cooking material at their boiling temperatures.
The present paper deals with the corrosive effects of solutions prepared by simulating those used in cooking on aluminum plate (JIS 1050) and foil (JIS IN 30) at 22 ± 3°C.
The solutions subjected to the test may be grouped into the following four categories depending on extent of corrosive effects observed on the aluminum material.
1) Strongly corrosive; Umezu (a salt containing vinegar made from Japanese apricots) and salt containing solutions of vinegar and organic acids with pH < 3.8, the corrosive region in the potential-pH diagram for aluminum.
2) Pitting; soy sauce with pH 3.8-8.6, the passive region in the potential-pH diagram for aluminum.
3) Loss of metallic luster; solutions of sodium bicarbonate and salt.
4) No visible change; solutions of saccharose, a chemical seasoning, and citric acid.
Introduction of air into some of the test solutions accelerated the effects mentioned above.

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Dissolution rates of some crystalline or granular seasonings, such as sodium glutamate and sodium glutamate-sodium 5'-ribonucleotide (granule or coating type) were estimated by measuring the heat of dissolution with a dewar flask calorimeter. The dissolution of the seasonings followed the first order kinetics except the compound seasoning of salt coated with sodium glutamate and sodium 5'-ribonucleotide. The dissolution rate depended on size of the granule and temperature. The rate constants were 10^-1-10^-2 sec^-1 and the half life of the dissolution was 5-14 sec at the room temperature. The activation energy of the dissolution of sodium glutamate was 11.4 kcal/mol.

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In order to know the effects of polluting gases on the physical properties of the fiber and on the color fastness, the experiments were carried out in the presense of dry SO₂ and dry NO₂ gases without daylight and the following results were obtained :
1) The tensile strength of the acrylic and polyester fibers showed a little change in the presense of SO₂ (1, 000 ppm) and NO₂ (1, 000 ppm) gases after 95 days of exposure, but for silk, nylon and Vinylon the tenacity and the elongation showed remarkable changes.
2) The elongation of the rayon and the acetate increased with the exposing time.
3) The solubility of the exposed wool and silk in 0.5 % aq. NaOH decreased with the exposing time.
4) The colors of the dyed samples were changed especially by the presense of NO₂ gas and a great deal of change were observed for blue colored samples. Their tensile strength also decreased very much along with the change in color.

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This paper aims to clarify the properties of some factors relating to Shari Hand Value of woven fabrics which is one of good feelings for summer wear in Japan.
The results are obtained as follows :
1) The rustring sound of high Shari Hand Value (8-10) have special frequency response, that is, the sound pressure within 1 kHz have about 70-90 dB, among from 1 kHz to about 6 kHz do below about 50 dB and among from about 6 kHz to 10 kHz do 50-60 dB, and it is experimentally clarified that the high sound pressure within 1 kHz results chiefly from the yarn (high twisted one) and the one over 1 kHz results from the fabric's construction.
2) In this experiments of the frictional property of fabric-to-fabric, the mean frictional coefficient μ and the variation of frictional coefficient μcv, could not be recognized to be closely correlated to Shari Hand Value.
3) Fabrics of high Shari Hand Value (6-10) have special constructions, that is, high twisted yarn such as 13-35 turn/cm in warp and 13-27 turn/cm in weft, yarn density such as 35-60 picks/cm and 35-50 ends/cm, and the crimp ratio such as 8-16% in warp and 6-18% in weft are used.

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As the first step to establish reasonable handling technique of sewing needles, we investigated the correlation between sewing skillfulness and hand movement during sewing. We used a movie camera to examine hand movement during sewing.
The displacement at some definite points of hands were extracted from series of movie pictures. Characteristic patterns were constructed by plotting the trace of left hand against that of right hand.
According to the length and the sweep-out area of a stroke of hand movement, it was found that hand movement during sewing is composed of 4 elemental movements. It may be concluded from the experiment that key point for handling of sewing needles is to move right hand regularly incorporated with left hand maintaining 4 elemental movements.

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In this paper we have investigated through questionnaires the effects of working mothers on the development of their children's perception of sex-role in employment.
The subjects are elementary school children, 295 boys and 258 girls, selected at random from the second, the fourth, and the sixth grade in Hiroshima, Mihara, and Fukuyama city. In the pre-test the subjects were asked to classify the given 50 vocations into 3 groups, that is, the first “for males only”, the second “for females only, ” and the third group, “for both”.
Five vocations were selected from the first group, and the second group respectively in view of standard deviation. In the investigation, “index of vocational-role stereotype” of each subject was made clear about each of 10 vocations by questionaires.
The data gained were analysed on three factors : sex, age, and maternal employment status. The results were as follows :
1. Sex : a) Maternal employment and kind of vocation give more influence on girls than boys. b) Compared with boy's, vocational-role perception of girls is more stereotyped by maternal employment.
2. Age : a) Vocational-role perception is elementary school children becomes more stereotyped as they grow older. b) On the fourth grade, non-maternal employment makes vocational-role perception of children stereotyped more rapidly as compared with maternal employment.

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From the household economical point of view, how do farmers care for their health and utilize medical facilities?
The author investigated the actual use of health insurances, premium and incomes. Data from the local hospital and interviews on the state of their lives were used as references. The samples were from T village in Shimominochi-gun, Nagano Prefecture, from April 1967 to March 1977.
Conclusions are :
1) There is great difference in individual utilizing his health insurance according to his life stage. Marks of utilizing his health insurance increases with his age and reaches the peak at his old age. If medical expenses at each life stage could be estimated, it is expected to be useful for household economical planning.
2) As for households utilizing their health insurance, direct elements that mark high are large families, small income earners and including old-age people in their families. Indirect elements are labor conditions, existence of medical institutions, geographical features and their way of life thinking.

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Recently, the household works have been remarkably rationalized by the development of many utensils, fixtures, appliances and machines. But the work of family meal cleanup is one of household works which many housewives do not like.
In order to make the work comfortable, it is very important to consider better work conditions such as the suitable height, the layout and the arrangement of base cabinet counters in the kitchen and etc. Now, it is significant to discuss the merits and the demerits of each type of sink which forms a part of the base cabinet counter in the kitchen from the viewpoint of housing design and home management.
The purpose of our studies is to measure the human energy expenditure of the meal cleanup work for each type of sink. At first, we have observed the actual methods of the meal cleanup work. Next, we have experimented which type of the sink is the most rational by measuring human energy expenditure and the characteristics of each type of sink (single bowl sink, double bowl sink I, II) have been compared.
The results are as follows :
1) The type of sink which is predominant in Japanese houses at present, is the single bowl sink type (67%), but the double bowl sink type has been gradually increased.
2) There are various types of the meal cleanup methods. Many housewives perform the meal cleanup work in their own way and habit. Consequently, an appropriate method has not yet been established as the way of living in Japan.
3) As the results of our studies, we have tried to make the model of meal cleanup method, that will be the most general and rational method (See Table 10, 11, 12).
4) The convenient type of the sink varies with each subjects, but the Western type of double bowl sink II which consists of 2 deep sinks is the most effective in saving human energy expenditure for dishwashing.

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[in Japanese]

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[in Japanese]

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