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The article discusses several space program and problems regarding the origin of the moon. A professor suggested that the recent data from the Lunar Orbiter photo satellites and the Surveyor landers show that the moon has been colder and less plastic throughout its history than the Earth. The chemical composition of the Moon which was secured by surveyors V, VI, and VII constituted important data with regard to its surface. Various suggestions about the origin of the moon are also emphasized in the article.

The temperature dependence of the threshold current in electron-beam-pumped (EBP) lasers using p-type GaAs (2 1.0 cm) at 27 kV is theoretically determined, taking into account the inhomogeneous distribution and the temperature dependence of the lifetime of the excess carriers. The computed dependence is found to be in excellent agreement with the experimental observation. A comparison is then made of the result with results obtained under different assumptions to confirm positively that, in the study of the performance of these lasers, the above two features cannot be ignored.
The purpose of the present communication is to determine the influence of the inhomogeneous distribution of the minority carriers on the temperature dependence of the threshold current in EBP lasers using p-type GaAs (2 10 cm) at 27 kV, taking due consideration of the variation of the recombination lifetime with temperature. [ABSTRACT FROM AUTHOR]

Discusses the mechanisms of temperature regulation of newborn babies. Invention of an incubator which not only provided for one-way flow of warm air, additional humidity and temperature monitoring of the environment but also allowed the infant complete freedom of movement; Mechanisms of homeothermogenesis; Significance of skin receptors particularly on the face and upper respiratory tract; Complications of hypothermia; Methods for reducing heat loss.

The effect of the glass transition temperature and the number of anionic groups of Dralon, Courtelle and Euroacril on the dyeing rate constants, Arrhenius activation energy and time-temperature cycle of isoreactive dyeing systems was studied. The dyeing rate constants depend more on the glass transition temperature than on the number of anionic groups, although these also have some effect. The Arrhenius law is followed in the glass transition range for the acrylic fibers; however, the experimental activation energy is not a suitable parameter for assessing the dyeing rate as it depends on the opening of the fiber. The isoreactivity equation was used to obtain time-temperature conditions leading to linear exhaustion during the dyeing process. Optimal conditions for a level dyeing of fibers may be determined through temperature control. [ABSTRACT FROM AUTHOR]

It has been shown that the average climatic chart, being based upon a topographic approximation to the true ground surface, is no more accurate than that approximation and cannot be adequately interpreted without it. Methods have been suggested for formalizing the approximative processes so as to reveal the most significant characteristics of the actual climatic distributions. These methods may be applied with benefit wherever a climatic element is affected by topography, even in areas of low relief. Applying this procedure to the description of the mean temperature of the Guinea highlands of West Africa, maps have been constructed which show the distribution of mean temperature in a fashion which gives it more meaning for he geographer. [ABSTRACT FROM AUTHOR]

Explains the difference of the physical principles between air temperatures over land and over sea. Implications of the principles for the distribution of air temperature in the coastal zones on land; Profiles of means of observed temperature drawn inland from the coast at three places in the U.S.; Function of horizontal distance from the coast.

A method is described for the reproduction of fine surface detail by spray casting with Wood's metal. Certain thermal properties of the alloy are presented as they bear on the practicability of the metal as a casting medium. The method is described as it was applied to the study and comparison of striations and surface irregularities on the fractured surface of glass fragments coming from a headlight lens of an automobile. [ABSTRACT FROM AUTHOR]

The article discusses the effect of temperature and light intensity on the rate of apparent assimilation of Fucus serratus, using material that had been kept under standardized conditions during the pre-experimental period. Each of the specimens gathered were kept for 5 days in diffuse daylight, darkened for 12 hours on the night previous to experimentation, and subjected to the same degree of illumination prior to the experimental period. Winkler's method was used to determine the amount of dissolved oxygen given out by the plant over a known period of time.

A letter to the editor is presented in response to the article "The Nature of Water Absorbed by the Protein Keratin."

In any false-twist-crimping process, a heat treatment followed by a cooling treatment is given to the threadline in the twist zone in order to 'set' the inserted twist. The majority of commercial machines use metal contact heaters to heat the threadline, and cooling is achieved by exposure to ambient air. The data in this paper provide a basis for a simple method of calculating the temperature-time history of the threadline in the twist zone from the known yam and process parameters. Nylon 6.6 yarns were used for the major part of the work, but data are also presented for Terylene, Ulstron, Lycra, and glass-fibre yarns. The measurements cover wide ranges of the process parameters, i.e., linear density, twist, tension, surface temperature, and yarn velocity. [ABSTRACT FROM AUTHOR]

Permanent setting of wool fabrics can be achieved by setting in steam autoclaves at temperatures above 100°C. An account is given in this paper of experiments performed on a laboratory scale and on full-scale equipment in which fabrics were set in rolls. One of the main problems in this kind of process is to ensure an even setting throughout the roll. Temperature and moisture regain are rate-determining factors in steam-setting, so a study was made of the temperature and moisture-regain changes in the different parts of the roll during heating up and subsequent steaming. The degree of set also depends on the steaming time and acidity of the cloth, but these factors are more easily controlled. The investigation shows that the steam-setting of wool-containing fabrics imparts a very high degree of permanent set and that reproducible and even setting may be achieved, provided that all treatment variables are kept under close control. Of all the parameters studied, the moisture regain seems to be the most important. [ABSTRACT FROM AUTHOR]

A letter to the editor is presented discussing the "Comparative Thermal Properties of Chlorofibres."

Specific-heat values are presented, in the temperature range from -70 to 100°C, for a modified wool at various water contents. The modification was analogous to a dyeing process and involved the uptake of 14% of an additive by the wool. As for untreated wool, an endothermic peak resulting from the fusion of absorbed water was found in the range from -30 to 0° C. The absorbed water exhibits a sub-division into freezable and non-freezable fractions. Heats of fusion of freezable absorbed water are given and compared with corresponding results for untreated wool. The integral heat of fusion at saturation water content is much less for treated than for untreated wool, as is the amount of freezable water. It appears that the treatment causes the exclusion of a considerable quantity of loosely held water. This is in accord with the concept, derived from Flory-Huggins solution theory, that one effect of the additive is to swell the wool fibres and thereby cause a greater resistance to further swelling at a given water content. [ABSTRACT FROM AUTHOR]

Details are given of a new thermal-transmission apparatus which is automatic in operation, which does not depend on the measurement of a heat flux, and which requires no guard plates to eliminate edge heat losses. The apparatus works on the principle that for conductors in series with respect to direction of heat flow, the ratio of the temperature drop across them equals the ratio of their thermal resistances, and the only measurements involved are those of temperature in the equilibrium state. The apparatus is suitable for testing the thermal-transmission properties of textile materials up to at least 1 in. thick. Data are presented for the thermal-transmission properties of timber and of plate glass determined with the new apparatus. [ABSTRACT FROM AUTHOR]

Fiber battings are becoming increasingly important for their uses as insulation. This paper reports the results of an investigation of the influence of thickness, applied pressure, bulk density and fiber type on insulation parameters such as Clo and Warmth Factor. The specific Clo value of 3.4 Clo per inch for battings falls between specific Clo values for fabrics and fabric-foam laminates. Warmth Factor, for a given batting weight, increased with thickness; and for a given thickness level, decreased with weight. Neither fiber type, within the limited range investigated, nor batting density had a significant influence on the intrinsic insulation of the battings. [ABSTRACT FROM AUTHOR]

The U. S. Government, the automotive industry and other large users of textiles have strict requirements for the tensile strength of nylon which will be exposed to sunlight. Usually Fade-Ometer and Florida sunlight exposures are used to determine in advance if the nylon will meet the requirements of its user. These methods, however, take considerable time. This paper reports the results of work that has been done in an attempt to shorten the necessary exposure time by using higher energy sources. Nylons yarns, with various treatments, were exposed to Fade-Ometor, Florida sunlight, ultraviolet, nuclear and laser energy sources. A correlation was attempted between the various types of exposures. [ABSTRACT FROM AUTHOR]

The article discusses a method for simultaneous measurement of Eh, pH and temperature of the skin. In comparing the skin surface pH in normal children with that of children who had seborrhoeic dermatitis, it was found that, in general, the latter had a more alkaline skin surface. At the same time it was noted that while there was much evidence to show that the acid and alkaline reaction of the skin surface of patients with certain skin disorders differed from that of normal persons, there were no data to indicate whether this difference preceded or followed the onset of the skin condition. It was to try to elucidate this problem that these investigations were undertaken.

An experimental study was made in an attempt to define the thermal environment of human teeth during open-mouth respiration. Results show that the environment can be affected considerably by ambient temperatures, ambient humidity, and dryness of the oral cavity. [ABSTRACT FROM AUTHOR]

Trapping of natural populations of Cylindroiulus punctatus, Tachypodoiulus niger and Polydesmus angustus showed that these millipedes are most active during darkness from one hour after sunset till one hour before sunrise. In summer (April-June) they become active in the afternoon in full daylight. It is suggested that this is made possible because millipedes develop a resistance to desiccation during this period. Seasonal variation in numbers trapped is not significantly correlated to either temperature or rainfall, but is associated with the breeding cycle of the millipedes. [ABSTRACT FROM AUTHOR]

There were no or only insignificant differences in temperature between the tulle bags and the open air. The pergamine bags, however, showed extreme temperatures with a strong excess during the daytime and a small but distinct deficit during the night. Concerning the relative humidity, data are available only from points in- and outside bags without leaves. The tulle bag showed only a small but the pergamine bag a considerable difference from the open air. [ABSTRACT FROM AUTHOR]

This paper recognizes the need for fabrics that are less flammable and describes criteria normally employed to evaluate flammability characteristics—ease of ignition, rate of burning, ease of extinguishment, types and amounts of smoke and toxic gas generation, thermal shrinkage, thermal insulation ability, and integrity of material at and during the time of heat and fire exposure. Fire-resisting properties of Nomex, Durette, Fypro, FRL-T-fibers, Kynol and PBI fiber are reviewed, and the performances of some of them exposed in garment form to a burning jet fuel fire are reported. Regular and modified PBI fabrics and the modified aromatic polyamlde fabrics are reported to show great promise for use in protective clothing. Their potential for general apparel and home furnishings is also considered. [ABSTRACT FROM AUTHOR]

The thermal characteristics of 16 concretes have been studied at elevated temperatures with the aid of thermogravimetry, dilatometry, and "thermal property tests." An analysis of the results is given from the point of view of material behavior under fire exposure. [ABSTRACT FROM AUTHOR]

Walls made from 44 different types of concrete masonry units were subjected to fire endurance tests. Tnree semiempirical formulas were used to express the fire endurance of these walls as a function of three geometric variables and two thermal properties which characterize the shape and material of the constituent masonry units. A numerical example is included to show the application of the formulas. [ABSTRACT FROM AUTHOR]

The effect of environmental conditions on the design for temperature and shrinkage stresses of reinforced lightweight concrete structures in the United States is presented. The range of temperature variation, relative humidity, dimensions and shape of members, percentage of longitudinal steel, concrete mix, coefficient of thermal expansion, and shrinkage coefficient of lightweight concrete have been studied. Design conditions for thermal variations and shrinkage in 135 localities throughout the United States are given in the form of a table. A design example is included to illustrate the use of the table. [ABSTRACT FROM AUTHOR]

This report presents a discussion of the materials and practices employed in proportioning, mixing, placing, and curing mass concrete, and of the properties and behavior of the hardened mass concrete. Particular emphasis is placed on the differences between mass concrete and conventional concrete. It is designed to serve as a reference for those engaged in the design and construction of concrete dams and other massive concrete structures. [ABSTRACT FROM AUTHOR]

This guide summarizes the present state of the technology. It presents and interprets the data on lightweight aggregate concretes from many laboratory and field sources. These include the comprehensive studies at the University of Illinois in 1931, the parallel investigations by the U.S. Bureau of Reclamation and the National Bureau of Standards in 1949, numerous recent laboratory studies, accumulated experience resulting from greatly increased and successful use, and performance of structural lightweight aggregate concrete in service. The guide is intended for the architect, engineer, contractor, concrete producer, and student. It includes a definition of lightweight aggregate concrete for structural purposes; it discusses in condensed fashion the production methods and inherent properties of lightweight aggregates for structural concrete. This is followed by current practices on proportioning, mixing, transporting, placing; properties of hardened concrete; and finally, the design of structural concrete, with special reference to the 1963 ACI Building Code. [ABSTRACT FROM AUTHOR]

Thermodynamic methods are presented for calculating, from the water adsorption isotherms, the change in unfrozen water content of a partially frozen soil with temperature at a constant pressure or with pressure at a constant temperature. Then, using pertinent experimental data for Na-Wyoming bentonite, the increase in unfrozen water caused by a confining pressure of 100 atm is obtained as a function of temperature. Such information is shown to be relevant to the mechanical properties of frozen soils under stress. [ABSTRACT FROM AUTHOR]

An extended equation was derived relating the relative partial molar free energy of water in a soil to its freezing point depression and relative partial molar heat content. The equation was used to prepare a table from which each of these three quantities can be ascertained if the other two are known. The table was used with experimental data to obtain a curve of freezing point depression versus water content for Na-Wyoming bentonite. Provided the activity of the liquid water in the clay is a single-valued function of the liquid water content, and that the ice has the properties of pure bulk ice, this curve also represents the relationship between freezing point depression and unfrozen water in the partially frozen clay. An equation for the heat capacity of a partially frozen soil was also derived. This equation was employed to calculate the heat capacities of the clay at different water contents and sub-zero temperatures. A comparison of the calculated unfrozen water contents and heat capacities of the partially frozen Na-Wyoming bentonite with the available experimental data indicated satisfactory agreement, especially as regards the unfrozen water contents. [ABSTRACT FROM AUTHOR]

A letter to the editor is presented in response to the article "Problems of Protection and Comfort in Modem Apparel Fabrics," by doctor K. Greenwood, Mr. W. H. Rees, and Mrs. J. Lordi in the 1971 issue.

A letter to the editor about hygroscopic textiles' specific heat in the April 1970 issue is presented.

The article presents a research report on critical thermal environment. It discusses the thermoneutral range for a homeotherm. Below the lower limit to the thermoneutral range, animal experiences a drop in the body temperature. It is reported that there are two basic processes which maintain "normal" body temperature. One is the metabolic process, which is an exothermic reaction, and the other is physical exchange of heat between the organism and the environment. It is stated that formulas, data and a number of parameters illustrated in the report must be considered in analyzing thermal relationships.