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Windows 95 may provide a major stimulus to Intelligent Network (IN) development, to real technological convergence between computing and telecommunication, and to a major reordering of research priorities in the field. The paper examines IN in the context of the evolution of convergence and the larger framework of information superhighway, infrastructure and society developments. It shows how the pace and direction of IN development will be driven by demand associated with organisational and institutional change, not the simple supply of greater capacity or the discovery of ‘killer applications’. This will be associated with a shift in priorities to distributed networking, information-based service development and a diversity of very specific new applications.

My colleagues at this symposium (cf, Eitinger, Frederick, Harnois) have discussed in their papers the immediate and long-term mental health consequences of victimization for the victim. My contribution to this discussion is to focus my attention on the family of the victim and to explicate two major axioms: First, that the family is the key factor in facilitating the emotional recovery of the victim; and second, that family members experience victimization themselves when another family member becomes a victim.

Five years ago in San Diego, USA, a Wheat Industry Utilization Conference took place under the direction of Y. Pomeranz who published the presented papers under the title Wheat is Unique.1 The information gathered in that publication still represents today the present state of knowledge on the structure, composition, processing, end-use properties and products of wheat. This is also true of the topics discussed here, the extraction of starch and gluten from wheat and extrusion cooking, on which the present author contributed two conference papers.2,3 Therefore, as only a few new findings can be reported, this chapter will concentrate on presenting the current state of knowledge on these topics with special reference to the functional characteristics of wheat gluten and starch. In so doing, the process technological possibilities for the extraction of starch and gluten from wheat flours and wheat wholemeal flours as well as the application of wheat starch and wheat flours for the manufacture of extrusion cooking products will be emphasized. Special emphasis is also given to the gluten-forming properties of wheat proteins and the two starch fractions present in the endosperm which differ not only in size but also in physical and chemical properties.

A global query in a mediator system to integrate distributed information is transformed into a set of its sub-queries and each sub-query is the unit of evaluation in a remote server. Therefore, it is possible to speed up the execution of a global query if the previous results of frequently evaluated sub-queries are materialized in a mediator. Since the integration schema of a mediator can be incrementally modified and the evaluation frequency of a global query can also be continuously varied, query usage should be carefully monitored to determine the optimized set of materialized sub-queries. Furthermore, as the number of sub-queries increases, the optimization process itself may take too long, so that the optimized set identified by a long optimization process may become obsolete due to the recent change of query usage. This paper proposes the adaptive selection of materialized sub-queries such that available storage in a mediator can be highly utilized at any time. In order to differentiate the recent usage of a query from the past, the accumulated usage frequency of a query decays as time goes by. As a result, it is possible to change the set of materialized sub-queries adaptively according to the recent variation of query usage.

I suppose my task in writing this paper is not only to outline the nature of action research but to open a discussion on how relevant the ideas of action research may be to the subject matter of the Conference. This I will attempt towards the end. I should however first make it plain that I write as a social scientist influenced particularly by the concept of the open socio-technical system first enunciated by The Tavistock Institute in U.K. At the time of writing my very limited knowledge of integrated production systems leaves me slightly doubtful how well the approaches to management problems of the systems analyst or systems engineer, and the social scientist, fit together.

The electromagnetic energy backscattered from an unknown target can provide information useful for classifying and identifying the target This is commonly accomplished by interpreting the radar echo in either the time or the frequency domain. For example, the natural resonances of a target are manifested in the frequency domain as sharp, discrete events and can be attributed to the unique global features of the target. Similarly, scattering centers are manifested in the time domain as distinct time-pulses and can be related to the local features on the target For target characteristics which are not immediately apparent in either the time or the frequency domain, the joint time-frequency representation of the radar echo can sometimes provide more insight into echo interpretation. The usefulness of the time-frequency representation of signals has long been recognized in the signal processing arenas. In the electromagnetic scattering community, the joint time-frequency analysis was first introduced by Moghaddar and Walton 1.2 to explain the measurement data from an open-ended waveguide cavity. In this paper, we present our work 3–9 in the generation and interpretation of time-frequency representations of wideband backscattered signals from targets, as well as our efforts to improve resolution in the time-frequency plane using wavelets and superresolution techniques. Similar efforts along these lines have also been reported by other researchers recently10–12.

This paper presents an overview of the reliability program to be conducted for the design and manufacture of the Collider Dipole Magnet (CDM). Reliability requirements, methods of analysis, and accelerated test methods are discussed.

The nucleosome core particle may be regarded as a basic structural unit of chromatin and thus of the chromosome. It is obtained by micrococcal nuclease digestion of chromatin and consists of about equal weights of DNA (146 base pairs) and protein (an octamer of two pairs each of the histones H2A, H2B, H3, and H4). Nucleosome structure has been reviewed by McGhee and Felsenfeld (6). Studies by small-angle neutron scattering using D2O/H2O contrast variation have given the overall dimensions of the nucleosome and have shown that the protein forms an inner core with the DNA located at the outer regions of the molecule (7,12). The x-ray crystal structure of the nucleosome core particle has been solved in projection to a resolution of about 25 A (3). Although this has given a more detailed description of the overall shape of the molecule than has solution scattering, the distinction between protein and DNA is not made. In this paper we show how the principle of contrast variation can be used in low resolution neutron diffraction to achieve this end.

In 1938 Wagner and Traud1 published a paper: “Concerning the Evaluation of Corrosion Reactions by Superposition of Electrochemical Partial Reactions and Concerning the Potential Formation on Mixed Electrodes.” This paper is today considered the classical paper on mixed potential theory, which postulates that, even without the assumption of the existence of local anodes and cathodes, one can explain corrosion reactions by assuming that cathodic and anodic partial reactions occur at the phase boundary metal/electrolyte in constant change with statistical distribution of location and time of the individual reaction. Wagner and Traud showed further that under certain conditions (yielding certain forms of the partial potential-current curves) it is possible to calculate the rate of a given reaction using electrochemical measurements. These principles were then applied to the dissolution rate of zinc amalgam in acid solutions. Good agreement was found between corrosion rates calculated from polarization curves using the technique, which today is called “Tafel slope extrapolation” and from the amount of hydrogen evolved. These experimental results were considered proof for the general postulations of the mixed potential theory.

This paper reports on an action research case study. The project involved nine classroom teachers using the action research process to develop an integrated curriculum algorithm and software classification system. The project also aimed to empower individual teachers with the knowledge, skill and confidence to understand, improve and transform their teaching procedures and practices with respect to the use of computers in primary classrooms. The discussion focuses on the development of the algorithm and the selection of a suite of software for the investigation of integrated curriculum topics. Also discussed is the impact of this type of instructional strategy on student and teacher motivation and performance. Also the lessons learnt in regard to software development, professional development, and the effectiveness of action research as a change agent.

Today, in the book and magazine trades, the cry is for attention. Sales quotas—not beauty—supply the measure of success. From every bookstall, on dust wrappers and magazine covers, pretty girls and desperate men, gangsters and bathing beauties, flaunt their smiles, their arms and legs and torsos. There are, of course, exceptions. Typography and paper, advertising and illustrations have improved; but with the mob in the saddle they count for little. In the nineties it was the mob that did not count. The artist was just then coming into his own, and he demanded—if the search was to be for beauty—the right to lead. Let us agree that the search proved futile. Still it was made. Old chests were rubbed, old manuscripts were studied, old lace was copied. Somewhere, they said—perhaps in the opium dens of Nanking or the tombs of the pharaohs, in the ruins of Troy or the boudoirs of Versailles —somewhere, some day, men will come upon the parent pattern, the perfect design from which all beauty stems. But ... no—the search proved futile. Yet it still goes on. It has lost something of its excitement. It has lost, for one thing, the enthusiastic support of White. It has gained decorum and order. It has become a business.

The New York to which Stanford White returned late in 1879 was a city of two, three and four stories, red brick and brownstone fronts, with perhaps a dozen passenger elevators in the downtown business and financial districts. The New York telephone directory was a card listing 252 names; there were no telephone numbers; you simply gave the operator the name of the person you wanted; service, costing as much as $20 a month, was slow, inadequate and limited to persons of wealth. Electric lights were unknown. Kerosene and gas supplied what (and it was not much) illumination there was. Matches, made with brimstone, and used to light the vilest cigars, almost choked you with their poisonous fumes. Offices, stores and residences—since there were no furnaces—were kept warm with big round stoves called Base Burners. The streets and avenues were lined with sycamores, poplars and telegraph poles. The trains and carriages were horse-drawn—with an extra horse to help out going over the hills. Men wore paper collars and cuffs and dickies: coats stopped abruptly at the hips: trousers were skin tight.

His tour ended, White was impatient to be back at his desk, applying his eagerly acquired knowledge to some useful purpose. He wanted—as he explained later to Simmons— to “justify his existence.” Even as a small boy, he had busied himself in small ways, trying to justify his existence, running errands for his father, waiting on his mother, carrying wood and coal, or working in the garden. He had no false pride. He did not save himself, as did his brother Dick, waiting for something worth-while to turn up. If his mother required a new shelf in the kitchen or a peg moved in some closet, if there was proofreading to be done for his father or a score to be copied, if Aunt Laura found herself unable to decide on wall paper for the guest room or Aunt Fanny needed a letter of introduction to some higher-up in Boston—one and all they turned to Stanford. And he never failed them. He never failed in after life. He was always ready with a word or a loan or a suggestion. To a young girl about to start for Central Park with her skates, he said: “I will design a skating bag for you.” When he came upon Abbott Thayer picking and choosing among old frames, uncertain which to select for the Academy show, he sat down to design a frame exactly suitable to the purpose.

To work for White was, at first, a fearful experience. A hurried statement of the requirements, a few hieroglyphics sketched rapidly on tracing paper, and they were off— “on an endurance race,” as Philip Sawyer says, “that might last for days or weeks or months and never let up until the work was finished.”

Phytochrome is the photochromic receptor for a variety of photo-morphogenic and developmental responses of higher plants to red light (for a detailed review of the subject, see Song 1983,Song 1988; Lagarias, 1985; Quail et al., 1986; Schaefer and Briggs, 1986; Furuya, 1987). In this paper, results on the study of the role of the chromophore on the phototransformation of 124 kDa oat phytochrome obtained in our laboratory will be reviewed.

The trend to replace aluminum with copper in IC interconnects requires that CMP be used to planarize the copper which has been deposited into RIE-patterned structures. Therefore, in this chapter, we discuss and develop a copper CMP model which predicts wafer-scale removal rate based on mass-transport theory and surface kinetic steps. The model seems to capture the essential features of the planarization of copper, and is very similar to the surface reaction kinetics model developed for low-κ CMP in Chapter 6. The model computes the concentration of the chemical reactant in the slurry using a convective diffusive mass transport equation. Surface kinetic equations are used to model the chemical reaction and mechanical abrasion processes at the wafer surface during CMP. The model approach for the CMP of copper is based upon a recent paper [7.1] and a PhD thesis [7.2]. The approach used here incorporates the fundamentals of pad/abrasive contact into the lubrication and mass transport process. It extends upon the low-κ CMP model developed previously, and may find applicability to dielectrics and other metals with well-known chemical reaction kinetics.

Instruction tailored to the individual student, learning and teaching outside the limits of time and spaceideas that were once considered science fiction are now educational reality, with the prospect of an intelligent Web 3.0 not far distant. Alongside these innovations exists an emerging set of critical-thinking challenges, as Internet users create content and learners (and teachers) take increased responsibility in their work. Learning and Instruction in the Digital Age nimbly balances the technological and pedagogical aspects of these rapid changes, gathering papers from noted researchers on a wealth of topics relating to cognitive approaches to learning and teaching, mental models, online learning, communications, and innovative educational technologies, among them: Cognition and student-centered, Web-based learning, The progression of mental models throughout a course of instruction, Experiencing education with 3D virtual worlds, Expanding educational boundaries through multi-school collaboration, Adapting e-learning to different learning styles, The student blog as reflective diary. With its blend of timely ideas and forward thinking, Learning and Instruction in the Digital Age will enrich the work of researchers in educational psychology, educational technology, and cognitive science.

It is important to develop mathematical models to estimate the release of buried radioactive waste to the biosphere and its potential impact on man. A necessary link in simulating this process is a model that accurately represents the subsurface transport. Among the analytical techniques used to predict the transport of nuclides in porous materials is the Green’s function approach (1), i.e., the response characteristics of a geologic pathway to an impulse function input. To date, the analyses all have set the boundary conditions needed to solve the 1-D transport equation as though each pathway were infinite in length. This paper critically examines the effects that the infinite pathway assumption has on Green’s function models of nuclide transport in porous media. It treats the more difficult problem of obtaining suitable Green’s functions for finite pathways whose dimensions may not be much greater than the diffusion length. Such pathways may occur in multipath representations of a waste repository, for example.

This paper presents development details and performance test results of a high performance cryogenic thermal switch (CTSW) for coupling redundant cryocoolers to cryogenic components with minimal off-cooler parasitics. Because gas-gap, hydride-pumped CTSW designs have not reliably met performance goals of an “on” resistance less than 2 K/W and an “off” resistance greater than 1000 K/W, a simpler, more reliable device was sought. The device that was developed is based on the reversible and highly reliable physical process of differential thermal contraction/expansion of stainless steel relative to beryllium. The 250 gram Swales differential coefficient of thermal expansion (CTE) CTSW (or SDCC) has just 3 machined parts: two cylindrical beryllium discs (same diameter, different lengths) and a thin-walled stainless steel tube. In ground testing, the SDCC demonstrated an “off” resistance of 1400 K/W and an “on” resistance of 1.2–2.0 K/W over a cold end temperature range of 25–50 K and a warm end temperature range of 230–300 K. Other issues addressed in the paper include alternative gas-gap (non hydride-pumped) designs, the option of “cross-strapping” and CTSW reliability. Finally, an advanced SDCC design is also briefly described that can reduce CTSW mass to just 50 grams with virtually no (surface area-induced) parasitic heat input into the cryogenic system.

In his recent book on research games, Bowen1 mentions games under development at his own Establishment for the study of information and decision-taking in Army ‘Command and Control’ organizations. This paper is the first published report of this work. It is offered at an early stage because the results obtained so far seem to raise issues of fundamental importance, not only to defence decision-taking, but to operational research in general.

Evidence is accumulating rapidly to support the concept that specific receptors for certain neuropeptides on lymphocytes may provide a means through which neurophysiological signals can influence immunological processes. Human lymphoid cells have been reported to have receptors for beta-endorphin (1), somatostatin (2), substance P (3), and vasoactive intestinal peptide (4), and a variety of investigations suggest that each of these neuropeptides can affect the behaviour of human lymphocytes in vitro. It has also been proposed that neurophysiological factors could have an important impact on the immune system in vivo by regulating the migration of lymphocytes through lymphoid tissue (5,6). This paper concerns experiments that were performed to test the hypothesis that receptors for the neuropeptide vasoactive intestinal peptide (VIP) influence the migration of T cells.

A novel human video object watermarking scheme is proposed in this paper, providing copyright protection of semantic content. The proposed method focuses on the existence of face and body regions within an initial image, however other cases can also be addressed. Initially detection of human video objects is achieved using two adaptive 2-D Gaussian models, one for skin color distribution modelling and the other for body localization modelling. A watermark is then designed using invariant Hu moments of each human video object, and the watermark insertion procedure is driven by an iterative encryption module based on chaotic functions. Performance of the proposed object based secure watermarking system is tested under various signal distortions and known cryptanalytic attacks.

Several papers have appeared on growing ferrite monocrystals and on the ferromagnetic properties of such crystals [1–4].

In the preceding paper** we pointed out that the measured values of crystallization pressure vary greatly. Our tentative theoretical study of growth in a crystal subject to a unilateral pressure has shown that the pressure sufficient to stop growth agrees well with the larger crystallization pressures found by experiment [1].

In the last few years several papers have appeared on the effects of ultrasonics on crystallizing substances [1, 2], These papers dealt with polycrystalline materials formed from melts, and did not touch on monocrystals. We give here some data on the effects of ultrasonics on monocrystals of potash alum.

The absorption spectra and other optical parameters of organic dye crystals have been studied for several years in the Crystal Optics Laboratory of the Institute of Crystallography, Academy of Sciences, USSR; the results have in part been published [1]. Many growth forms have been examined, in order to find forms with optical orientations suitable for our purposes. Some of the growth forms we found have not previously been described, while others are interesting cases of forms already known. The data are of interest in morphology and growth form contexts. This paper deals with the growth forms of the thiazine and oxazine dyes we have studied.

The cryostat described in this paper was developed to fill a need for a general purpose laboratory apparatus to provide a fairly large thermostated space in which any constant temperature between room temperature and -320°F could be maintained at ±1°F, even under conditions of substantial heat input to the cryostat. Flexibility of operation, simplicity and reliability of automatic control were the primary considerations in the development of the cryostat.

The successful operation of the present types of infrared detection systems depends primarily on the response and sensitivity of the most vital part of the system, namely, the detector sensing element. Many of these elements, in turn, require cooling to temperatures in the vicinity of 75 to 100°K in order to detect present-day targets traveling at high speeds. One of the major problems in the development of these infrared systems has been to provide adequate cooling in a reliable manner either over short or long periods of time with a minimum of cryogenic hardware. The reliability factor and me logistic field requirements have been only approximately met by the majority of present-day, open-type cooling systems. Moreover, for those systems that require long periods of operation in flight, there is frequently a significant weight advantage in favor of closed-system refrigeration. Thus, there exists a definite need for a closed infrared detector cooling system. The latter is the subject of this paper.

Increased interest in compressed liquid hydrogen, particularly at high pressures, has resulted in a need for a more extensive correlation of the available P-V-T data. This paper presents correlated values of pressure, specific volume, and temperature of normal hydrogen from 14 to 80°K, up to 200 arm pressure and for volumes from 26 to 70 cm3/mole. The correlation is a result of the compilation of data in this range from the available data in engineering and scientific literature» Graphical presentation of P-V-T values on P-T coordinates results in isometrics that are straight lines, except at extreme conditions. Values of compressibility, Z = PV/RT, were calculated from the correlated P-V-T values for presenting in tabular and graphical form.

The problem described in this paper consisted of the development of an integrating gas or mass flowmeter, pressure and temperature compensated to ±5 percent in mass or gas flow and whose readings are transmitted by wiring to an indicator located at a distance. The following general requirements applied to the flowmeter problem: 1) Maximum flow rate of hydrogen gas—approximately 150 cubic feet per hour (355 grams per hour) 2) Entering gas temperature —(+50°C to -65°C) 3) Ambient pressure—2 to 15 psia 4) Meter to be integrating or totalizing 5) Meter not to be affected to any large degree by tilting or by the normal vibration encountered in transportation.

Initial test results on the performance of a pumped subcooled helium cooling system designed for the Fermilab Energy Doubler project were presented earlier [1]. This paper presents additional details of the design, construction, and operations of the 122-m test loop.

The tremendous increase in efficiency of the iron hydroxide catalyst described in the preceding paper (A-3) made it extremely attractive for use in the large CEL-NBS hydrogen liquefier s. The 30% chromic oxide gel used for catalyzing the ortho-para conversion of hydrogen in the liquefier s has proven reasonably satisfactory except that to obtain 95% para liquid at full plant capacity 50 liters or more of the catalyst is required. This amount fills a considerable portion of the liquid reservoir and has large heat capacity which appreciably prolongs the time required to cool the liqurfier on start-up. The liter or so of the new catalyst estimated for accomplishing the same degree of conversion would have a negligible heat capacity.

For reasons of economy or convenience it is sometimes desirable to store liquid hydrogen without loss. Due to inevitable heat leaks to storage dewars, it is necessary to periodically refrigerate the hydrogen load to prevent the build-up of excessive pressures. The purpose of this paper is to indicate the function of liquid hydrogen refrigerators and to describe a new refrigeration system developed by the NBS-AEC Cryogenic Engineering Laboratory.

In an earlier communication1 a description was given of the gas refrigerating machine, developed in the Philips Laboratories at Eindhoven, Holland. This new type of refrigerator was introduced as an air liquefier, but it was mentioned that it is also suitable for the production of cold in general, particularly between -80°C and -200°C. Among other applications, the separation of air into its components was cited as one of the most promising fields. The present paper deals with this subject and describes a small plant producing liquid nitrogen, utilizing the gas refrigerating machine.

A transfer line is a pipeline used to convey very cold fluids from one place to another. The transfer line described in this paper was specially designed for use with liquid hydrogen but could easily be used to transfer other cold fluids such as liquid nitrogen, air or helium. It is installed in the NBS-AEC Cryogenic Engineering Laboratory’s liquid hydrogen plant to transfer liquid hydrogen from the liquefiers to the storage and transport dewars. Special emphasis is placed on features which contribute to lower heat leak, simplicity and reliability. The primary design consideration is to reduce heat transfer from the warm ambient atmosphere to the liquid. In our application, high vacuum is used as the insulation in the annulus between the two concentric tubes with the cold fluid flowing through the center tube.

This paper describes an airborne cryogenic system for pneumatic power generation which has been developed and constructed by Sundstrand-Turbo. This system maintains a gas storage bottle at 3000 psi upon demand by pumping stored liquid nitrogen from a vacuum jacketed container. The pump is a small high pressure multi-piston type driven by a turbine utilizing the 3000 psi stored gas supply. Figure 1 shows a picture of this system which will be described more fully. The system shown has a storage capacity of 20 liters, 36 pounds of liquid, and will deliver approximately 6 pounds per minute of nitrogen gas.

Geysering for years has been recognized as a problem in long liquid oxygen supply lines. Euptured supply ducting has been reported due to the destructive nature of the pressure surges encountered. With design decisions to place the liquid oxygen tank forward of the fuel tank in the missiles, long supply lines (approximately 25 feet) became necessary to supply liquid oxygen to the propellant pumps. To reduce weight, thin stainless steel ducting is utilized and it becomes imperative to have an exact knowledge of the geysering phenomena for this configuration and of the pressures which could be expected in the supply ducting. The author presents a discussion of the series of tests made on simulated missile plumbing at the San Diego Division of Convair during 1955 and 1956. The various methods of geysering suppression investigated are also presented in this paper. The test hardware was designed to simulate, as near as possible, the internal volumes, masses and heat transfer areas of the actual missile equipment in the liquid oxygen supply system.

This paper presents the design modifications incorporated into the original Norelco liquefier for converting it into a compact efficient recondenser of flash gases from liquefied storage systems. Industrial applications and economics for the recovery of flash gases are also included.

The object of this paper is to present and briefly discuss the experimental data obtained for the transfer of heat to boiling hydrogen from a relatively large flat surface under a variety of conditions. These conditions include the angle of orientation of the surface, surface condition, and hydrogen pressure. The effect of vertical height of the heating surface was also noted. A limited amount of experimental data can be found in the literature on heat transfer to boiling hydrogen, but the results are not in close agreement. In almost every case a very small heater was used and the effects of a number of variables were not investigated [1–3], Although the experimental data bracketed data obtained by theoretical correlations, it was not possible to determine which experimental data were more accurate.

The concept of magnetic energy storage is well known, but the engineering task of developing economical superconductive storage units is a relatively new endeavor. Much of this effort depends on the large-scale production of high-current conductors, large refrigeration systems, etc. However, it is also vital to determine magnet configurations that use these materials in the most efficient ways. This paper discusses the relations which connect energy and magnetic field to a variety of cost-related parameters.

This paper describes some of the work done at the Boeing Airplane Company on crew compartment environmental control. Primarily, the discussion will be about a test run to determine the feasibility of a cryogenic — supplied “wash-through” cabin conditioning system. This system was designed to provide a “shirtsleeve environment” in the crew compartment.

It is the purpose of this paper to describe the non-conventional design features of the Norelco gas liquefier which is based upon the principle of the Stirling cycle and the demonstrations of J. W. L. Kohler1 at the last conference. The Stirling cycle consists of two isothermal steps for compression and expansion and two isochors for cooling and reheating. A schematic and diagrammatic representation of the process in four phases is shown in Figure 1, illustrating the piston and displacer position at the beginning of each phase.

The previous paper discusses the need for cryogenic coils and briefly discusses the various metals which are considered for electrical conductors. This paper will briefly describe some of the engineering problems of building such coils.

This paper is concerned with the design of simple resistance thermometer bridges for the control of temperature over very wide ranges.

The cryogenic pumping problems which are the concern of this paper are encountered in the fueling systems for relatively large missiles that use a cryogenic liquid oxidizer, particularly liquid oxygen. The problems arise from the necessity of accomplishing rapid transfer of large quantities of liquid oxygen with pumping systems which (1) must be relatively light in weight in order to minimize the initial cool-down time period, (2) must be very reliable, and (3) must place minimum requirements on the storage vessel from which the liquid oxygen is pumped.

This paper describes some of the design, construction, and test work which was undertaken to develop a helium-to-hydrogen heat exchanger. Hydrogen is a potentially important fuel for certain propulsive and secondary power applications where low molecular weight and high heat of combustion are important. In many possible airborne system applications, hydrogen is stored at cryogenic temperatures and heated in a heat exchanger before being burned to produce energy. If the heat source is one or several items of equipment which require cooling, use of an intermediate heat transfer loop is indicated. A logical intermediate heat transfer fluid is helium, because of the absence of freezing or condensation at liquid-hydrogen temperatures. This is the background for the present work. The problem statement numbers were evolved from an airbreathing engine design study, but the technology is applicable to the presently more interesting nonairbreathing secondary power devices as well.

It has been known for some time that certain Ascomycetes and Fungi Imperfecti are capable of attacking cellulose and nonlignified materials. For instance: 1. A great many can attack cellulose plant fibers such as cotton, causing serious destruction of fabrics. 2. Others may grow through wood, living on stored food materials, such as starches and sugars in the ray cells, and thereby stain and discolor the wood. 3. Others not only utilize the food material within the ray cells but also the pectin and hemicelluloses of the walls. When the cells are dissolved, porosity is increased, and the wood becomes more absorptive of water and preservatives. It is of interest to note here that certain bacteria also are capable of dissolving the ray cells in logs stored in ponds for the purpose of preventing stains and decay (Ellwood and Ecklund, 1959). Increased absorptiveness may cause considerable drying and paint-maintenance problems. Increased porosity in wood can, on the other hand, be of value to the wood preserver. In experiments directed toward improving the penetration of preservatives, chemicals, such as sodium fluoride, have been sprayed on logs to stimulate the growth of molds, particularly Tricho-derma (Lindgren, 1952). 4. A few bark-inhabiting Ascomycetes are known to decay small branches and twigs. Their attack on the lignified walls of tracheids, vessels,and fibers, however, has been regarded as unimportant.

This paper discusses the effect of air condensation upon the thermal conductivity of conventional insulation. The difference between the published values of thermal conductivity and those experimentally determined on simulated liquid-hydrogen rocket propellant tanks are presented.

Various aspects of the mechanisms of action, insofar as they are known, of sulfur, dithiocarbamates, and related fungicides have been reviewed by McCallan (1957), Horsfall (1945), and Martin (1959). The present paper reports some comparative biochemical effects of these materials on metabolism of organic acids by way of the citric acid cycle. The purpose of the study was to determine whether all of these fungicides affect the same or different biochemical processes and to relate the observed effects to the structure and chemical properties of the compounds and the enzymes.

Several methods are available to increase the efficiency and lower the cost of hydrogen liquefaction. Recent investigations aimed at more efficient hydrogen liquefaction have concentrated on the application of expansion engines, particularly turbo expanders, more efficient purification, and development of and effective use of ortho-para catalysts to improve liquefaction cycle efficiency. The purpose of this paper is to show the relative effects of these liquefaction parameters, with special emphasis on the effect of ortho-para converter applications. This will be done by discussing the results of theoretical calculations for two simple cycles which indicate the effects of cycle modifications, expansion engine efficiency, and ortho-para catalyst location. For this study, purification was not treated as a cycle parameter.