bluuebunny/crossref_metadata_2025 huggingface dataset:
Stethoscopic Examination of Welded Products
Authors: Dawson J. R.
Published: July 2009

Except for the hydrostatic test of welded pipes or other pressure vessels, a non-destructive test which could be considered satisfactory for commercial use has not been available until recently. A means of testing the welds without damaging the completed structure has long been sought for, and of late favorable attention has been given the stethoscopic test and the X-ray examination. A great number of pressure vessels and the thousands of pipe joints both in power lines and in cross-country transmission lines offer ample evidence of the ability to obtain safe welds through the use of a suitable procedure control. Under the procedure controls which have been employed, the examination has consisted almost entirely of tension and bend tests of material of the same thickness, and welded under the same conditions as those employed in the structure. Each operator who is to work on a given job is required to make test plates which will meet definite specifications. This is analogous to testing by sampling. However, on account of the attitude of various regulatory bodies, and because of the increased confidence which may be given those not familiar with welding, more extensive application of welding may be made when satisfactory non-destructive tests of the welds are employed. Non-destructive examination is useful for welds not made under procedure control. For these reasons the industry is fortunate in having the stethoscope and X-ray methods available. The stethoscope was first used for testing welds by A. B. Kinzel and this application has since been investigated and developed further by Mr. Kinzel and others of the Union Carbide and Carbon Research Laboratories. The same principle is involved as is used by a blacksmith when he strikes a piece of metal to find if it rings true, or when staybolts are tested by tapping them with a hammer. The stethoscope is the type commonly used by physicians (Fig. 1). The coneshaped end piece is preferred, and over this end piece is placed a soft rubber cap. When listening through the stethoscope, the operator presses the end of the cone with the soft rubber covering firmly against the metal containing the weld which is to be tested. This prevents undue damping such as might occur if the hard cone were in immediate contact with the metal, and because of intimate contact between the soft rubber and the metal, outside noises do not interfere. The weld is tapped with a hammer, as shown in Fig. 2, at intervals of about one inch along its entire length. The size of the hammer and the force of the blow will depend on the thickness of the metal being examined. The pipe, pressure vessel or structural steel member being tested will have a natural vibration, and there will be also forced vibration, both of which are set up by the blow. The sound due to the natural vibration should first be determined, and then the important things to be listened for are the first sounds obtained upon striking.
Inspection of Welding Made by the Watertown Arsenal
Authors: Jenks G. F.
Published: July 2009

In the development of its welding practice, the Watertown Arsenal has utilized its X-ray equipment which had been installed for other purposes. This practice has been of great assistance in inspecting welds and particularly in developing the methods and shop technique for the varied work of ordnance construction. It has also been utilized in training welders, and on control of quality of output. The practice has been based on a small shop engaged for the most part on hand work by metallic arc, but equipped for and using other methods of welding. Machine welding by the metallic arc is used to a limited extent and a practice for flash welding is being developed. A considerable portion of the output consists of experimental designs. All divisions of the laboratory have been utilized in developing welding technique, and in interpreting inspection practice. Not-withstanding its limitation, X-ray inspection has become standard practice and is relied upon as the most potent single factor in maintaining high-quality workmanship.
Welding Inspection
Authors: Kraus R.
Published: July 2009

The question, “can the quality of a finished weld be determined from its external appearance,” is frequently asked by those who become interested in the application of welding. An answer in the affirmative can be given. A good and a bad weld have their definite characteristics, easily recognized by average inspectors and supervisors, no elaborate methods or rules being necessary.
Use of Statistics in Writing Specifications
Authors: Goffman Casper , Manuele Joseph
Published: July 2009

By the word “specification” as used in this paper is meant any specification employed for the purpose of defining the desired quality of any product for utilitarian or aesthetic purposes. A specification is necessary because different lots of the same product might possess the same quality characteristic in different degrees, whereas, for best results, it is desired that the particular quality characteristic be maintained at a definite level and within very definite limits. It is the function of the specification to define this level of quality and the limits within which the quality level may be allowed to vary. For this purpose the specification must possess two operating characteristics: 1. Accuracy.—The specification must define the desirable quality level and its permissible variation with sufficient clarity as to allow definite discrimination between good lots and bad lots. 2. Economy.—The specification must permit discrimination between good lots and bad lots without the requirement of 100 per cent inspection, or the examination of all units in a lot. This is particularly important in the case of destructive testing, where the test operation itself would leave us no “good parts.” The fundamental characteristic of a manufactured product which makes the application of statistical measurements essential is the variation inherent in the product. No two pieces produced are exactly alike regardless of the refinement of the process. Although in some cases the differences are smaller than can be detected with the measuring devices on hand, we can be assured that differences do exist.
Endurance—A Criterion of Design
Authors: Bean W. T.
Published: July 2009

The internal-combustion engine is one of the most complex fatigue machines ever devised. Fundamentally it is a machine in which high cyclic loads are created. The manufacture of its components to withstand fatigue has been a problem for engine builders for over three-quarters of a century. We of the “Continental” group (Continental Motors, Gray Marine, Wisconsin Motors, and Continental Aviation) welcome the opportunity to participate in any series of discussions on the fatigue problem. Since the engine builder, perhaps more than any other manufacturer, has been plagued with fatigue failures, he has been forced to find a solution. Experimental stress analysis, the current answer, has been developed as a tool to indicate areas of high stress concentration by the use of photoelastic, stresscoat, and strain-gage techniques. The practical manner in which an engine builder may use stresscoat and straingage techniques to analyze a fatigue failure is the subject of this paper, for endurance strength is automatically achieved when the fatigue problem is solved.
Pneumatic Fatigue Machines
Authors: Quinlan F. B.
Published: July 2009

During the war the General Electric Co. was forced to make fatigue tests on gas-turbine buckets, because a correlation between standard test specimens and actual bucket performance was very difficult to obtain. While our experience in this work has been largely with gas-turbine buckets, it would seem that this difficulty applies to a wide variety of parts that are subjected to reversed bending stresses. The buckets have, roughly speaking, a crescent-like cross-section. In precision cast buckets, the metal usually has a finer grain structure at the points of the crescent than in the heavier mid-section. Grain structure has a pronounced effect on the fatigue strength and grain structure is determined by the shape of the cast part; consequently, fatigue tests on actual buckets became a necessity. Under operating conditions, the buckets are subjected to periodic disturbing forces as they pass through regions of alternately high and low gas pressures. In view of this, it was logical to vibrate these buckets with an interrupted air stream.
Automotive Rear Axles and Means of Improving Their Fatigue Resistance
Authors: Horger O. J. , Lipson C. H.
Published: July 2009

Eighty-eight automobile rear axles taken from production stock were subjected to fatigue loading in rotating bending. These axles were made from NE 8650 steel, quenched and tempered to 388 to 444 Brinell. These axles were unmachined in the tapered body portion between the splined end and bearing seat adjacent to the wheel; fatigue failure in service and in these tests developed in this body section. Seven different conditions were investigated as to their influence on axle fatigue strength, which included the effect of straightening, three degrees of shot peening, and recarburization. Unstraightened axles had about 25 per cent higher endurance limit than straightened ones. This decrease in fatigue resistance was accompanied by surface tensile stresses of about 120,000 psi. induced by cold-straightening. Shot peening of straightened axles gives about three times the endurance limit of those not peened. Axles were also recarburized and then accidentally became slightly decarburized in heat treatment. Their fatigue resistance was not improved by this process even though the decarburization was shallow compared with axles not given a carbon-restoration treatment.
Stress Concentration and the Fatigue Strength of Engine Components
Authors: Gadd Charles , Ochiltree N. A. , Zmuda Andrew
Published: July 2009

Estimates either of the relative or of the absolute mechanical strength of machine components must frequently be made by the engineer. Such an estimate will usually involve primarily, a consideration of the geometry of the part, or the manner in which stresses are concentrated as a result of changes in section. The stress analysis must then be placed in terms of fatigue strength through the application of endurance strength data obtained from the literature. A look into the literature, however, leaves one somewhat in doubt as to the validity of any strength estimate whatever, since most fatigue data are from simple beam type specimens which may not take properly into account the numerous pitfalls encountered in attempting to extrapolate to parts of complicated section and in the as-manufactured condition. For this reason the authors have, over the past several years, attempted to compile data for checking the theoretical strength of parts of complicated shape against their actual fatigue strength. In each case, the “theoretical” analysis has been by measurements of maximum local stress at the points of stress concentration, rather than by calculation, using either 1/16 or 1/8-in. extensometers, while the actual fatigue strength has been obtained by testing a sufficient number of factory-made specimens to permit the construction of a complete S-N diagram (1,2).
Equipment for Magnetic Particle Inspection
Authors: de Forest A. V. , Betz C. E.
Published: July 2009

Magnetic particle inspection has now had a full fifteen years of development and has won an important place in many fields as a standard inspection method. Its nondestructive nature, the ease with which it can be applied, and the fact that in general it requires no elaborate and costly installation has made it particularly attractive. The development of the method as it is in use today actually dates from 1929. Before that time the general principle had been described by Major William E. Hoke in a patent issued to him in 1922 following work which he had done in connection with the Hoke gage blocks. In 1929 two radical improvements were made. These consisted of the introduction of circular magnetization, and the use of magnetic particles specifically designed for inspection; and useful applications date from these improvements. First applied for locating quench and grinding cracks and later to finding fatigue cracks at overhaul, the method gradually spread to locating nonmetallic stringers and seams in bar stock and spring wire and to welding, forging and casting defects, in many cases supplementing or supplanting X-ray inspection in heavy sections.
Magnetic Particle Inspection
Authors: Lester H. H.
Published: July 2009

The Ordnance Department is interested in magnetic particle testing methods in connection with procurement of various items of Ordnance material. It is used both for final acceptance inspection and as a control in weldment manufacture.
Specifications and Procedure
Authors: Spooner A. P.
Published: July 2009

It is not the purpose of this paper to duplicate information now available in recent publications of our Society. There is much useful information, for example, in the two A.S.T.M. Tentative Methods: Methods of Magnetic Particle Testing and Inspection of Commercial Steel Castings (A 272-44 T), and Methods of Magnetic Particle Testing and Inspection of Heavy Steel Forgings (A 275-14 T). A very informative pamphlet “Magnetic Particle Testing of Commercial Forgings” has been published by the Forging Manufacturers' Association. These publications cover such phases of the inspection as application, surface preparation, magnetizing equipment, powders, methods of magnetization, current required for production of suitable magnetic field strength, application of powders, interpretation and reporting of results, demagnetization, etc. Included in these articles are comments on the various conditions which may be developed by the magnetic particle test such as tears and cracks, inclusions, shrinkage, blow holes, chills and chaplets, scabs, sand, cold shuts, and abnormal indications sometimes found in steel castings. Reference is also made to cracks, seams, laps, thermal checks, pipe, bursts, inclusions, segregation, flow lines, and abnormal indications in the use of this testing method on forgings.
Miscellaneous Applications of the Magnetic Particle Test
Authors: Snader E. A.
Published: July 2009

Although this Symposium on Magnetic Particle Testing covers some extremely interesting and important applications of the test, it must by no means be considered that the value of the test is limited to the more or less specialized fields to which the greater part of the discussion has related. It is probably safe to say that nowhere has this test proven of greater value than in the aviation industry, and the unsurpassed performance of our aircraft is to a large extent due to the ability of the magnetic particle test to detect the most minute flaws that exist at the surface of ferrous parts. The importance of keeping weight to an absolute minimum necessitates a control of materials and processes that probably is not encountered in any other field. It is difficult to think of a single ferrous airplane part that is not subject to this test, including everything from bolts and nuts to welded struts and engine mounts. The assurance of complete freedom of surface, or in some cases near-surface, defects in the many highly stressed parts that go into plane and engine manufacture reduces greatly the factor of safety that would otherwise need to be employed in the design of the parts. However, in addition to the aircraft and other specialized fields, there are many other applications of the test, a few of which will be discussed here.
Introduction
Authors: Ashcraft E. B.
Published: July 2009

The plans and arrangements for this symposium were made by a committee composed of G. G. Manov, D. S. McKinney, G. A. Perley, and E. B. Ashcraft. The plan adopted was to attempt to cover four broad topics in the symposium: a history of the field; a discussion of fundamentals and the broad theoretical basis for pH determinations; recent advances in the principal methods and techniques; and applications to particular fields. Within the limitations set by time and the availability of speakers, the following papers represent the execution of this plan. The historical review is presented in a single paper by C. N. Myers. The theoretical discussion of the basis for pH determination is covered principally in the two papers by M. Kilpatrick and by D. S. McKinney, P. Fugassi, and J. C. Warner and partly by that of G. G. Manov. Recent advances in the principal methods and techniques are presented in the papers by M. Dole, F. R. McCrumb, and G. G. Manov. Methods of making pH determinations in a particular field, that of petroleum products, are explained in the paper by L. Lykken. Brief mention of recent applications to various fields is made also by M. Dole.
Historical Review of the Hydrogen Electrode and the Calomel Cell in the Measurement of Hydrogen Ions
Authors: Myers C. N.
Published: July 2009

The determination of hydrogen and hydroxyl ions has gone through the hands of skillful architects of science—men with vision and imagination seeking the truth in the explanation of the hitherto obscure phenomena and behavior of living and chemical processes. About six decades ago there came a vision to a group of chemists like Arrhenius, Nernst, Van't Hoff, and Ostwald who advanced our knowledge and theories of osmotic pressure and electrolytic dissociation. It is from these men the term ion and the electrical nature of matter and reactions received their place in the equilibrium equations of physical-chemical reactions. Before proceeding further, the author wishes to apologize for the inadequacy, on account of limited time and space, of this review of the important historical concepts associated with the development of hydrogen ion determination. Very frequently it is stated that the specific data which are important but purely historical should be left to the historian. Be that as it may, the author's recommendation would be in the form of a suggestion that such a review would save much time and money for future workers in the field of hydrogen ion determination. This review should be carried out and correlated by a carefully selected group of pure and applied scientists. Arrhenius proposed the theory that acids, bases, and salts in the presence of water are broken down into parts which are called ions. Solutions of these substances gave a greater osmotic pressure than would be expected from the concentrations employed. The lowering of the freezing point of water was too great. In dilute molecular solutions of compounds such as H2SO4, BaCl2, etc., the molecular lowering was nearly three times the normal. These facts accord perfectly with the results of the measurements of osmotic pressure, and furnish strong evidence in favor of the theory of electrolytic dissociation—an ion lowering the freezing point to the same extent as a molecule. The theory was tested by determining the values of the coefficient i which had been introduced by Van't Hoff into the general gas equation in order that it might be applied to the osmotic pressure of solutions. The coefficient i was determined by the well-known freezing point method, and, by a comparison of these values, the theory of electrolytic dissociation at once came into prominence.
Recent Advances in the Theory and Use of Glass Electrodes for pH Determinations
Authors: Dole Malcolm
Published: July 2009

Approximately 75 papers on the glass electrode were abstracted by Chemical Abstracts during the war years, 1941 to 1945, the number falling off with time, until papers listed for 1945 reached the low figure of only 9. Undoubtedly 1946 will also show an abnormally small number of papers published on the glass electrode, because scientists, graduate students, and research workers now beginning new investigations will not have data ready for publication in time to be abstracted by the 1946 Chemical Abstracts. The only other electrode system which is much used, the quinhydrone, was not studied as extensively as the glass electrode, as indicated by the fact that only 19 quinhydrone papers were listed during the five years of war (see Fig. 1). Apparently there is considerably more interest in the glass electrode; hence this paper is limited to discussion of it.
Acid-Base Equilibria in Aqueous and Nonaqueous Solutions
Authors: Kilpatrick Martin
Published: July 2009

For uncharged proton acids in basic solvents of not too low dielectric constant the reaction Ax+S⇌SH++Bx−.........(1) takes place, the extent of the reaction depending on the strength of the acid Ax relative to the basic strength of the solvent S. The equilibrium constant for this reaction KAxS=CSH+CS·CB−CAx.........(2) is usually expressed as the more commonly used dissociation constant Kc which includes the concentration of the solvent. KAxS·CS=CSH+CB−CAx=Kc......(3) The constant Kc varies with ion concentration, and in the limited range of concentration where the Debye-Hückel theory applies the following equation may be used to determine the thermodynamic equilibrium constant [Kc]° logKc=log[Kc]o+Aμ.......(4) where A2=0.434ε2(DkT)3∕2·πN1000 The values for A at 25 C. are: for water (dielectric constant D=78.54) 1.020, for methyl alcohol (D=31.5) 4.02, for ethyl alcohol (D=24.2) 5.97, and for butyl alcohol (D=17.4) 9.79. For more concentrated solutions no theoretical equation can be given, but Table I shows that the change in the equilibrium constant is of considerable magnitude.
Functions of Rubber Reserve—Past, Present, and Projected
Authors: Hucks W. R.
Published: July 2009

The growing international tension of the years 1937 to 1940 gave rise to American military concern over the strategic requirements for rubber. In the latter part of this period, shortly before the beginning of hostilities, arrangements were consummated between the United States and Great Britain for the exchange of 500,000 bales of cotton for 90,000 tons of natural rubber. Before this tonnage had reached our shores, the United States Government authorized the Reconstruction Finance Corp. to purchase even larger quantities of rubber. This corporation, in turn, established the Rubber Reserve Co. to handle this task on June 28, 1940. The seriousness of the supply situation for the United States is indicated by the fact that by the end of the year 1939, there were only 125,000 long tons of natural rubber on hand. Rubber Reserve Co. was very active in 1940 to 1941 and contracted for the purchase of 800,000 long tons of natural rubber during this period. The increased civilian use of rubber prevented the total accumulation of this amount for stockpile purposes, so that, as a result, at the end of 1941 the country stockpile amounted to 503,000 long tons, with 100,000 long tons additional afloat. This was less than one year's supply at the best prewar consumption rate, and also considerably less than the 700,000 long tons per year required for military and civilian requirements. In May of 1941 Rubber Reserve entered into contract with the four major rubber companies to construct synthetic rubber capacity to the extent of 40,000 long tons annual rate. During the first half of 1942, plant capacity was increased to the astounding total of 805,000 long tons, consisting of 705,000 tons of GR-S, 60,000 tons of GR-I, and 40,000 tons of GR-M.
Development of Methods of Chemical Analysis of Synthetic Rubber
Authors: Tyler Willard P. , Higuchi T.
Published: July 2009

The purpose of this paper is to trace the development of chemical testing of synthetic elastomers during recent years and to discuss the present status of these analytical methods. As the synthetic rubber industry expanded rapidly, it became necessary to find chemical as well as physical methods to control the product within specification limits. It was also necessary to provide chemical methods for the identification of synthetic elastomers and for chemical analysis of compounded synthetic stocks. It is only fair to state that even as late as 1942 the available information regarding such chemical methods was negligible. Furthermore, even after this critical initial period, there was disagreement as to what specifications and chemical tests were necessary. It is true that several rubber and petroleum manufacturers had made synthetic elastomers before this time, but no concerted effort to standardize on process or methods of testing was made prior to the inception of the Government synthetic rubber program. The synthetic rubbers—more properly called synthetic elastomers—to be discussed in this paper are, for the most part, the three elastomers known to the industry by Rubber Reserve Co. names of GR-S, GR-M, and GR-I, and the oil-resistant butadiene-acrylonitrile copolymers. GR-S is the large tonnage general purpose elastomer, a copolymer of butadiene and styrene; GR-M is a polymer of 2-chlorbutadiene-1,3 having special uses; GR-I is a nearly saturated copolymer of isobutylene and isoprene, particularly useful for inner tubes. The greater part of this paper will be devoted to GR-S since the cooperative work sponsored by the Rubber Reserve Co. dealt largely with this elastomer with the result that more information is available concerning it than about any of the others.
Developments and Improvements in Methods of Stress-Strain Testing of Rubber
Authors: Schade J. W. , Roth F. L.
Published: July 2009

At the beginning of the Government rubber program in 1942 and 1943, the methods of stress-strain testing given in A.S.T.M. Methods D 15 — 41 and D 412 — 41 were employed. It was generally recognized at that time that the precision of stress-strain testing of rubber vulcanizates left much to be desired. Consequently, as mentioned in the paper by Mr. Hucks, the Committee on Specifications for Government Synthetic Rubbers, in order to improve the precision of existing methods and to develop better methods, established a Subcommittee on Physical Testing. The name of this subcommittee was changed in 1944 to the Subcommittee on Test Methods and its scope was broadened to include chemical methods, also. The major portion of its efforts, however, continued to be devoted to physical testing. This subcommittee comprises representatives of the Office of Rubber Reserve, the National Bureau of Standards, several rubber goods manufacturers, the synthetic rubber plants, and the Bureau of Ships. This paper deals with the accomplishments in the field of stress-strain testing emanating from the laboratories represented by this group.
Development and Standardization of Tests for Evaluating Processibility of Rubber
Authors: Taylor Rolla H. , Fielding J. H. , Mooney M.
Published: July 2009

This paper reviews the important wartime developments in methods of standardization and tests, heretofore unpublished, relating to the evaluation of processing quality. The term processing quality or processibility is used in the rubber industry to describe any one or all of the inherent characteristics of a rubber which may affect its behavior during the manufacturing process. The nonuniformity of various rubbers and the changes in behavior which occur with slight changes in the method of treatment make the determination of this quality one of the major problems in the manufacture of rubber goods. In an effort to measure this quality by laboratory methods, investigators had developed a number of different types of apparatus, usually with the idea of measuring some property which could be expressed as a function of the viscosity or the elastic recovery. In accordance with Scott Blair (1)4 and others, the term viscosity as used in this paper is not limited to Newtonian systems. In 1942 the Technical Committee of the Rubber Reserve Co., primarily composed of technical representatives from the rubber industry, reviewed methods existing at that time and decided that some measure of the viscosity should be used for controlling the processing quality of GR-S and that the Mooney viscometer (then called the Mooney plastometer) should be the standard instrument for this purpose in Government Synthetic Rubber plants. When the production of GR-I began, it was adopted as the standard control instrument for this rubber also. The Williams plastometer had been used as the control instrument for neoprene production and consequently was used for GR-M. Since May 1, 1947, however, the Mooney viscometer has been specified for grading GR-M production.
Testing and Grading of Wild and Plantation Rubbers
Authors: Bekkedahl Norman
Published: July 2009

In a search through the great number of papers in the scientific journals dealing with plantation and wild rubbers, one comes to the conclusion that the rubber technologists concerned with manufacturing operations would much prefer to purchase their natural rubber on the basis of specifications set up by scientific laboratory tests than from the results of the past and present-day methods of evaluation solely by superficial appearance. Ever since the beginning of the rubber industry, the natural-rubber broker has purchased crude rubber from the producer and sold it to the manufacturer on the basis of cleanliness and a few other rule-of-thumb tests or observations. This is a very peculiar situation because practically all of the other ingredients used in the manufacture of rubber products are purchased on the basis of specifications which are dependent on scientific laboratory tests. Also the final rubber products are usually sold on a performance or quality basis rather than on appearance alone. Except for cleanliness, the superficial appearance of a crude rubber has very little in common either with the intrinsic quality of the crude rubber or with the quality of the product made from it. Practically all uses for rubber are for products in the vulcanized state, so why should not the manufacturer be interested in purchasing his crude rubber on the basis of tests made on its vulcanizate? The present method of evaluating rubber on superficial appearance alone is, however, not altogether unwarranted or unsound. It involves an extremely simple and rapid procedure and does not require an expensive laboratory and scientifically-trained personnel. It operates on the assumption that if the crude rubber is clean, uniform in color, bubble-free, “rust”-free, and free from fungus formations, it probably has had extreme care in its preparation and will therefore exhibit its optimum physical and chemical properties. This assumption, however, obviously does not always hold true.
Introduction
Authors: Erck E. H.
Published: July 2009

This Symposium on Synthetic Lubricants was sponsored by Technical Committee B on Lubricating Oils of A.S.T.M. Committee D-2 on Petroleum Products and Lubricants to fill the need for its dissemination of technical data pertaining to these materials. It has been arranged by the Instrument Oil group of Utility Section U-V since this section has been engaged in the study of synthetics. An attempt has been made to include in this symposium a panorama of this subject so that people technically engaged may participate in the discussion in addition to the appeal it may have to general interest participants. The principal speakers include technical representatives of the leading chemical concerns employed in the manufacture of synthetic materials currently used as lubricants. It will be clearly shown that the need has been definitely established for materials having properties superior to petroleum for use in aircraft. Mr. C. C. Singleterry will corroborate this statement and show the rapid development of synthetics upon recognition of the need. The growth and interest in these materials has resulted in intense study and development in anticipation of fulfilling the requirements of heretofore unsolved lubrication problems.
Introduction
Authors: Ashcraft E. B.
Published: July 2009

This Symposium on Spectroscopic Light Sources was organized with the thought in mind that the time has arrived when the field of spectrochemical analysis can best be advanced by a detailed examination of its various subdivisions. The techniques and instruments used in spectrochemical analysis divide themselves more or less naturally into three groups having to do, respectively, with the excitation of the sample, the resolution of the spectrum, and the determination of the relative intensities of the light emitted at various wavelengths. It was thought by the committee that the first of these groups is perhaps the least advanced and that a detailed study in the form of a symposium might be a particularly desirable contribution at this time. It is realized of course that none of these particular problems can be divorced entirely from the over-all problem of correlating the observed intensity ratios with the actual composition of the sample. In this connection the question of sample history and preparation is of prime importance and might well be considered either as a separate topic or as a part of the larger subject of excitation. The first paper of the Symposium attempts to summarize present practice and to correlate it with the more detailed studies to follow. The second paper presents a detailed study of a particular kind of source. In the next paper spectroscopic sources are considered from the viewpoint of the physicist who has specialized in the study of electrical discharges in gases rather than from the viewpoint of the spectroscopist. The last paper gives results of a study by a unique method of various processes occurring in the discharge. Finally, a number of well known practicing spectroscopists have been asked to present discussions. These discussions are not limited to the contents of the principal papers and might be more correctly characterized as short contributions of interest in connection with problems of current practice.
A Study of the Controlled Spectrographic Spark Source
Authors: Enns J. H. , Wolfe R. A.
Published: July 2009

The purpose of this study was to investigate the stability of spectrographic spark sources when controlled by the well known synchronous (Feussner) interrupter, or an auxiliary air-gap interrupter. Kaiser and Wallraff's (1) work on this subject is the most complete literature available. The work of H. Barkhausen (2), D. R. Roschansky (3), and H. T. Simon (4) also has been referred to in studying the behavior of a spark gap in an electric circuit. Wherever feasible, observations have been made upon the instantaneous events in the system by introducing a suitable pickup whose output was recorded with the aid of an oscilloscope. First the source was considered from the standpoint of what goes into the system. That is, the over-all electrical circuit for each of the two spark sources was analyzed part by part. One assumption throughout this work has been that a basic requirement for a stable source (a source giving optimum reproducible spectrographic results) is that it shall have as nearly as possible identical starting conditions for successive sparks. The sparks are the result of a charged condenser discharging through an inductance, resistance, and the several air-gaps in series. Therefore, assuming at this point that the air-gaps return to fairly identical conditions between sparks, it remains essential that the starting voltage on the condenser be the same. Also it will be assumed that events during the transient discharge be maintained consistent from spark to same. The second phase of this work was that of studying the light output from a controlled spark source. Because of the pulsating nature of the generated light signal, instantaneous light-intensity observations are possible with an oscilloscope employing a-c. amplifiers. for the most part, a study of the instantaneous shape of the characteristic light signal (5) was not attempted, but rather, observations were made on the peak values only. The fluctuation of these peak values was considered a measure of the constancy of the source output.
Some Properties of Gas Discharges Used As Spectral Sources
Authors: Mason R. C.
Published: July 2009

In this paper, the properties of the positive column of d-c. arcs and low and high frequency a-c. arcs are presented. Some electrical characteristics are obtainable from external measurements of current, voltage, length, and section. The gas temperature can be determined from the velocity of sound in the arc, the absorption of fast particles, and the intensities of band spectra. The ion density can be estimated from the observables. The question of the existence of thermal equilibrium in the positive column is examined critically, and some of the conditions under which it might occur are found. In some regions of arcs, and at some instants in varying-current arcs, probably no equilibrium exists. Caution must be used in speaking of the temperature of discharges.
Short-Period Phenomena in Light Sources
Authors: Dieke G. H.
Published: July 2009

There are errors and limitations in each step of the technique used in spectrochemical analysis. With a systematic study of the fundamental processes involved in the various steps, an insight is gained into the causes of the errors; thus, a basis is acquired for changing the technique so as to avoid error as much as possible. For instance, in many cases the limitations of the photographic technique are the greatest source of error. By careful plate calibration and rigorous control of the photographic process these photographic errors can be considerably reduced. The properties of the light source then present the greatest source of errors. If the light source is not well regulated, it may be the limiting factor in any case. In the future, when probably the shortcomings of the photographic process more and more can be avoided by using direct photoelectric methods for intensity measurements, the shortcomings of the light sources will be felt increasingly. Attempts to find more suitable light sources have been made and will be continued. Such attempts, to be successful, require a thorough knowledge of the fundamental properties of the light sources. As the fundamental processes occurring in the light source are flu complex, a thorough understanding of the behavior of most sources is still lacking. In order to make much future progress, suitable methods for studying what is going on in the light sources must be devised. In this paper the author attempts to give an account of some such methods.
Introduction
Authors: Mougey H. C.
Published: July 2009

The programs of the meetings sponsored by the Detroit District are usually on subjects related to the automotive industry on account of the interest in this subject in the Detroit area. In the current year, 1947–1948, the Detroit District is honored by the election of one of its members, Mr. T. A. Boyd, as president of American Society for Testing Materials. Mr. Boyd was chairman of A.S.T.M. Committee D-2 on Petroleum Products and Lubricants for many years. In 1947 Committee D-2 held its fall meeting in Detroit. As a result of this combination of circumstances, it seemed particularly appropriate to hold a joint meeting of the Detroit District and Committee D-2 and to have the subject of this meeting, “Petroleum Products as Related to Automotive Equipment.” Automobiles and petroleum products are such a common part of the life of all of us that we are prone to overlook their importance. With approximately 36 million cars, busses, and trucks on the roads at the present time, and counting only 85 horse power for each unit, there is a total of three billion horse power available to take care of our transportation needs, exclusive of railroads and ships. When we realize that it requires two million barrels of gasoline per day to feed these “mechanical horses,” and enormous amounts of lubricants of various kinds to enable them to do the work we demand of them, we begin to have some conception of the very large multiplier attached to even small gains in efficiency and performance. Because of the magnitude of the oil and automotive industries and their importance to the American way of life, it is fitting for the American Society for Testing Materials to do what it can to encourage cooperation between these two industries, and to promote developments that will increase their efficiency so that they may continue to serve the public and to improve upon the fine record they have already established.
The Efficient Production and Utilization of Motor Gasoline
Authors: Holaday W. M.
Published: July 2009

This paper attempts to present a general picture of the past trends and present factors involved in finding, producing and refining petroleum, and in the utilization of motor gasoline. The economic utilization of petroleum for transportation is not solely a problem of producing high octane number fuels and adapting engines to use these fuels, but is one which also involves the economics of the entire petroleum industry. If the automotive and petroleum industries are to perform their duty to society, engines and fuels must be provided which will result in the most economical transportation with the lowest consumption of our natural resources. In reviewing technical publications on this subject, one finds that various trends in fuel quality have been supported from time to time which, when summarized, indicate that fuels will become more volatile, less volatile, higher in antiknock quality, lower in antiknock quality. Most of these predictions were given in good faith and represented the trends existing at the time. An example can be given to indicate the effect of new developments on these trends. When thermal cracking had reached what appeared to be the final stage of development a few years ago, the maximum octane number level was rather low. However, with the advent of catalytic cracking the petroleum industry developed another tool which has made possible the production of a larger percentage of gasoline from a barrel of crude oil at a higher octane number level than could be attained by thermal cracking. Another factor, which has often been overlooked, has a material effect on the quality of the individual products. This factor is the dependency of one product upon another. Petroleum refining today must not be looked upon as a unit that makes gasoline and lubricating oils only, but rather as a highly technical operation that refines and manufactures products as light as methane through gasoline, solvents, fuel oils, lubricating oils, asphalts and petroleum coke, to say nothing of numerous specialty products. In such an operation the national resources of natural gas, crude petroleum, and coal can be processed to furnish these products. In order that the most efficient consumption will result, engineers in the industries that manufacture equipment to consume these products must cooperate and understand the economics of both the refining and the consumption. This paper reviews the present state of the art in the petroleum industry for the production of gasoline and outlines some of the steps that must be considered to obtain its most economical utilization.
A Review of Tractor Requirements as Related to Fuels
Authors: Bowers Raymon
Published: July 2009

Today there are two basic types of tractors in use: the carbureted or Ottocycle type and the diesel. The fuels used in the carbureted type tractor are gasoline, distillate, and kerosine; the fuels used in the diesel are commonly called fuel oil, furnace oil, commercial diesel fuel or just diesel fuel. Most carbureted tractors in this country, at the present time, are operated on gasoline, the balance on distillate. Very little, if any, kerosine is used here. However, foreign operators frequently request kerosine or distillate burning equipment on carbureted engines, and tractors for export are generally so equipped. Most every one is familiar with the extensive use of gasoline in the automobile, truck, bus, airplane, and many other automotive applications; also with the rapidly increasing demand for diesel fuel for diesel powered locomotives, trucks, buses, and industrial equipment of all kinds. When gasoline and diesel fuel are used so extensively in similar applications, why does the tractor industry continue to build distillate burning tractors? There are several factors involved, but the most important one is that of over-all economy. We all know that as long as there is a demand for distillate tractors the industry will produce them. And there will be this demand just as long as the distillate tractor does an equivalent amount of work at a lower over-all cost than either the gasoline or diesel tractor. In the past, distillate tractors were popular because this fuel was plentiful and its cost low. This is not the case today, because with the increased demand for distillate fuels for oil burner and diesel use, there is no surplus and the cost is high. Another factor, and a very important one, is the fact that a good tractor distillate has to be held to a reasonably close specification and consequently there is very little difference in refinery cost between it and gasoline.
The Complexity of Tractor Fuels and Taxation
Authors: Anderson Arthur B.
Published: July 2009

The complexity of tractor fuels and taxation can be appreciated only by considering first the background of state motor fuel tax and petroleum inspection laws against which is reflected the interest of the states in tractor fuels. Since the State of Oregon first adopted a gasoline tax to aid its road building program, this tax has become universal among the forty-eight states and is a major source of state revenues throughout the nation. While a degree of uniformity does exist among the states, it is found largely in such matters as the unit of measurement of the tax rather than in the tax rate, in the regularity and frequency of collection of the tax rather than in the use of uniform reporting forms or procedures, in the general application of the tax to receipts or sales at the supplier and jobber levels rather than in the final retention of or relief from the tax in so far as the ultimate consumer is concerned.
Influência da composição corporal e da idade sobre a densidade óssea em relação aos níveis de atividade física
Authors: Nascimento Thales Boaventura Rachid , Glaner Maria Fátima , Paccini Marina Kanthack
Published: July 2009

OBJETIVO: Verificar em relação ao nível de atividade física (NAF) o quanto cada componente da composição corporal e a idade influenciam na densidade óssea (DO). MÉTODOS: Amostra de 22 homens e 42 mulheres (21 a 51 anos) classificados com NAF recomendado e não recomendado para a saúde. A DO do fêmur foi mensurada por meio da DXA. RESULTADOS: Por meio da análise de regressão linear múltipla stepwise (p < 0,05), a idade explicou negativamente a DO em todos os grupos, exceto nos homens com NAF recomendado. Nas mulheres com NAF não recomendado, a gordura relativa (G%) e a massa gorda (MG) explicaram a DO em todas as regiões de interesse no fêmur, com aumento de até 0,007 g/cm² por quilograma de MG. CONCLUSÃO: A DO na área de Ward sofre maior influência da idade nas mulheres. A MG e a G% exercem influência positiva sobre a DO das mulheres com NAF não recomendado.
Avaliação do Serviço de Referência em Triagem Neonatal para hipotireoidismo congênito e fenilcetonúria no Estado de Mato Grosso, Brasil
Authors: Stranieri Inês , Takano Olga Akiko
Published: July 2009

OBJETIVO: Avaliar o Serviço de Referência em Triagem Neonatal para hipotireoidismo congênito e fenilcetonúria no Estado de Mato Grosso. MÉTODOS: Estudo transversal, utilizando-se dados secundários dos exames realizados no período de janeiro de 2003 a dezembro de 2004. RESULTADOS: Foram feitos 66.337 testes de triagem com uma cobertura populacional inferior a 70%. A prevalência de fenilcetonúria foi de 1:33.068 nascidos vivos, e de hipotireoidismo congênito foi de 1:9.448 nascidos vivos. Apenas 22% das amostras foram coletadas na idade recomendada; a maioria realizou o teste de triagem entre 8 e 30 dias de vida. A mediana da idade na coleta do teste foi de 12 dias. Verificou-se que o serviço teve dificuldades na reconvocação dos casos suspeitos e dificuldades financeiras na obtenção dos insumos laboratoriais. CONCLUSÕES: A idade na coleta e o atraso na fase de confirmação diagnóstica foram os principais motivos para o atraso do início do tratamento dos casos detectados pelo serviço.