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Most of the papers presented at this symposium deal with advanced packaging designs and techniques. This paper, however, will attempt to describe some of the best regressive thinking of packaging design, which we choose to term “illogical packaging design.” Illogical design is not a concept; rather, it may be termed a lack of concept. Occasionally, illogical design is accidental rather than premeditated. The illogic of design stems from many sources and takes many forms. It is our aim to bring to your attention some of the bad design habits existing in industry today. By describing them, the job of eliminating these bad design habits and features should be somewhat easier.

It is the purpose of this paper to show the extent of liquid oxygen boil-off in a typical rocket test facility such as the Edwards Rocket Base, and to explain the measures that can be utilized to prevent the boil-off without interfering with the development of the test rocket.

The scope of this paper is restricted to a discussion of nuclear phenomena, a subject in which interest began at the turn of the century, and which has developed with the improvement of the microscope.

Qualitative identification of gas chromatograph. (G.C.) fractions has created problems for the organic chemist. One of these concerns the Limit of detection for any given compound which can be achieved with a method designed to trap a G.C. peak for further analysis. This paper presents the limits of detection found attainable in the qualitative analysis of specific organic compounds. These limits were established by utilizing an activated charcoal capillary to trap the G.C. fraction prior to introduction into a Bendix Time-of-Flight mass spectrometer via the hot filament probe.

In the few years since its discovery, gas chromatography has revolutionized the conduct of research in organic chemistry and biochemistry. Its application to problems in inorganic chemistry has been slower in coming, but it is now clear that gas chromatography has much to offer to the inorganic chemist as well. For a more detailed discussion, bibliography, and historical development of inorganic studies, the reader is referred to the book entitled Gas Chromatography of Metal Chelates. Many more recent papers are listed in Ref. 2 and 3.

The exploitation of the Mossbauer effect in the fields of physics and chemistry [1–4] has been remarkable in the seven years since its discovery [5,6]. The applicability of this tool can be extended to the field of biophysics, although as yet the potential of the Mossbauer effect for biological studies has not been fully realized. Comparatively few papers have been published concerning the investigation of biological molecules and related compounds. In most cases the Mossbauer spectra of these molecules are treated somewhat as a curiosity and very few detailed interpretations of the data are made. In this paper we will try to point out both the usefulness and limitations of the Mossbauer effect for biological studies and, if possible, give appropriate examples of measurements which have been made on biological materials. The authors apologize for drawing rather extensively on their own work in this connection; however, the very limited amount of published work in this field makes this unavoidable. We believe the included reference list is complete with respect to published Mossbauer investigations of a biological nature.

In this paper results obtained by Leif Abrahamsson, Herb Keller and myself are discussed*. Consider a system of ordinary differential equations $$ {\rm{L}}\left( {\rm{y}} \right){\rm{ = \varepsilon }}\left( {{{\rm{d}}^{\rm{2}}}{\rm{y/d}}{{\rm{x}}^{\rm{2}}}} \right){\rm{ + A}}\left( {\rm{x}} \right)\left( {{\rm{dy/dx}}} \right){\rm{ + B}}\left( {\rm{x}} \right){\rm{y = F}} $$ (1.1) in the interval 0 ≤ x ≤ 1 with boundary conditions $$y\left( 0 \right) = \alpha ,{\text{ }}y\left( 1 \right) = \beta .$$ (1.2)

The normal procedure for a quantitative measurement of two phases with an X-ray diffractometer is to scan or count the intensities of two diffraction peaks and then to calculate the ratio of the two phases using an appropriate equation. This paper will describe an improved method of quantitatively measuring two phases in a sample. The diffractometer, which was constructed by Philips Electronics Instruments, consists of two fixed scintillation counters mounted at the Seeman-Bohlin focusing positions for the two desired diffraction lines. Each counter is preceded by a lithium fluoride curved crystal monochromator. The output from each counter feeds to a separate scaler which can be arranged to gate both scalers at a preselected number of counts. At this point a tape printer prints out the counts for both scalers. These counts are then related to the proportions of each phase present by an appropriate equation. Most of the electronics are solid-state designs. This paper will describe the instrumentation and show how it can be used to measure rapidly and precisely the ratio of anatase to rutile in a titanium dioxide system. The savings in time over the conventional method can be as much as 100 to 1.

This paper discusses the structure of the solar envelope and the physical processes which might occur in the envelope. The envelope is the region between ≈2R⊙ and ≈(25–50) R⊙.

Members of the rodent family Sciuridae occur on all continents except Australia. Squirrels are one of the few families of mammals to have such a nearly cosmopolitan distribution. However, patterns of dispersal and evolution within the family have only recently come under study (Moore, 1959, 1961; Black, 1963; Gromov eta L, 1965). Recent paleontolegical data (Black, 1963, 1965b, 1966; Bruijn and Mein, 1968; Mein, 1970; Sulimski, 1964) and chromosome studies of living squirrels (see Nadler, 1969; Voronstov and Lyapunova, 1970), taken together with Moore’s (1959) morphological studies and his classification of living squirrels exclusive of flying squirrels, now provide a basis for a reconstruction of “historical processes and events” within the family. Such is the intent of the present paper. Evolution within the Sciuridae and exchange between the Nearctic and Palearctic will be considered for the most part at the generic level. This is done for two reasons: fossil and living genera are more nearly equivalent taxonomic categories; and, too little is known about mid- and late-Pleistocene species of squirrels in Eurasia to allow for discussion of species dispersal in most groups.

This paper presents a numerical study of theoretical amplitude spectra of surface Rayleigh and Love waves. These spectra are of obvious interest in any problem connected with surface-wave dynamics: determination of source magnitude or energy, focal depth, and source mechanism and investigation of the resonance properties of layers or of the earth’s structure.

Development of large-scale helium production operations in the United States over the period from World War I to the present is an interesting chapter in the history of the chemical industry. Of particular interest is the method of production whereby helium is extracted from certain helium-bearing natural gases by processing at very low temperatures and relatively high pressures. Most of the helium has been produced by a method developed and used by the Federal Bureau of Mines. Other methods have been proposed1, 2, 3, 4 but are not known to have been used extensively or for large-scale production. The Bureau of Mines process has been described only in a general way in the past 5, 6, 7, 8, 9. It is the purpose of this paper to give additional information, including some details of the process cycles and equipment used.

The present paper is concerned with the conservation laws in general relativity as expressed in terms of the Landau-Lifshitz complex and their role in the development of the successive post-Newtonian approximations to the equations of general relativity of a perfect fluid. In § I, the known conservation laws of Newtonian hydrodynamics are formulated in a language that the relativistic laws appear as natural generalizations. In § II, the same laws are considered in the framework of general relativity. In particular the conserved energy is identified as the difference between the (0,0)-component of the Landau-Lifshitz complex and the conserved rest-mass energy (\(={{c}^{2}}p{{u}^{0}}\sqrt{-g}\)). In § III, the development of the first and the second post-Newtonian approximations to the equations of relativistic hydrodynamics are described and illustrated. And finally in § IV, the manner in which one can obtain the equations of the 2 1/2 — post-Newtonian approximation is described. In this approximation all terms inclusive of O(c−5) beyond the Newtonian are retained; it is in this approximation that terms representing the reaction of the fluid to the emission of gravitational radiation by the system first make their appearance. It is shown how the derived radiation-reaction terms of O(c−5) contribute to the dissipation of energy and angular momentum in agreement with the predictions of the linearized theory of gravitational radiation.

A number of papers in this symposium “have focused upon the relative theoretical merits of the “population distance” and “population structure” approaches to local human variation. The blood polymorphic, anthropometric, and migrational information collected from 18 south-central Bougainville villages are, at this date, the only data set analyzed by both sorts of techniques (FRIEDLAENDER et al. 1971, FRIEDLAENDER 1971), and the different applications illustrate in a practical way the different aims, as well as the different merits and problems, of the two approaches. Here I would like to review the different sorts of conclusions the techniques have provided, and then present some new analyses from the population structure vantage point.

This paper describes the effect of velocity and temperature on the friction coefficient of both filled and unfilled rubber vulcanizates sliding on smooth ice. It has been shown that the mechanism of the friction of rubber on ice is the same as that on other smooth surfaces under similar low sliding speed conditions and that the maximum friction coefficients are similar. The Williams Landel and Ferry equation is used to superpose curves of the velocity dependence of the friction coefficient at different temperatures to produce a master curve and therefore to demonstrate the viscoelastic nature of the frictional mechanism. The frictional behaviour depends on the condition of the ice track and a tentative explanation for this observation is suggested. The frictional properties of vulcanizates containing various amounts of a reinforcing carbon black filler have been studied. The effect of the carbon black filler on the friction coefficient correlates with changes in the low temperature dynamic properties of the vulcanizate obtained using a torsion pendulum. The effect of contact pressure on the friction coefficient has been investigated using both filled and unfilled vulcanizates at low sliding velocities. The results are in accord with a theory which has been used successfully to describe the behaviour on other smooth surfaces. The combined effect of a high contact pressure of the order of 30 psi (2 kg cm-2) with sliding speeds up to 40 mph has also received attention and the results are discussed in terms of frictional melting of the ice at the interface.

Linearized subfringe interferometric holography, described in Chapter 4, has been used for detection and recording in an acoustical holography system which is presently under development at McDonnell Douglas Corporation. This paper describes the laboratory system used to test the feasibility of the concept and to work out some of the problems associated with this technique. Acoustical hologram movies have been recorded at 16 frames per second, with each frame being recorded in 6 microseconds from a 100microsecond burst of sournd. Each movie frame is the recording of a complete acoustical hologram of 30-cm aperture at a sound frequency of 1 MHz. With a sound wavelength of 1.5 mm we have resolved about 2.5 mm and imaged objects less than 1 mm. The threedimensional image volume is about a 30-cm cube. There is no acoustic lens in the system and thus the resolution is limited by the 30-cm aperture of the acoustic hologram. We have resolved about 1.5 times the Rayleigh limit.

Lately there has been an increasing interest in ME-techniques involving the detection of resonance scattered conversion electrons. This is mainly due to the inherent possibilities of surface studies. As pointed out, for example, in a number of articles by Spijkerman et al.(1), the detection of conversion electrons in the iron-57 case will limit the surface examined to the outermost hundreds of Angstroms, if metallic iron is used as the absorber. Several papers involving the use of this technique in metallurgical connections have been published recently (2). They are all based on a “depth integral” approach, i.e. all electrons that are scattered are detected regardless of what depth they originate from.