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Electron microscopy and local X-ray spectral analysis (utilizing an electron probe) have been used to evaluate structural heterogeneity in ion-exchange membranes. X-ray patterns, reflecting radiation intensity changes along the test sample proportional to the fixed charge density, can be obtained through X-ray microanalysis. Electron microscopic studies of ultra-thin sections of ion-exchange membranes indicated that the structural heterogeneity expressed by alternating zones with various electron densities associated with the presence of pores in the membranes is the basic feature of these membranes.

The influence of pile parameters (height, density, and weight) on echo-loss absorption by carpets is investigated by means of a swept-frequency technique. None of the three factors is found to be significant, and it is presumed that other parameters are more important in determining the acoustic behaviour of a carpet. The size of a test sample and the incident-noise level used in the test are shown not to affect the evaluation of sound-absorbing ability.

In the early 1940’s, Garner, Nissan and Wood (1)1) and Weissenberg (2) made the first attempts to measure normal stress2) in viscoelastic fluids undergoing shear. Fifteen years later, by the late 50’s, a considerable body of data on various fluids and techniques had been generated. Markovitz and his colleagues, recognizing the importance of collecting different measurements on one sample, completed an extensive program on a solution of polyisobutylene. In surveying this work in 1958, Markovitz (3) said ... “The data lead us to the conclusion that two contradictory types of theory are needed to correlate different pairs of experiments. Obviously, there is something wrong. We need more and better experiments to decide among the various possibilities.” The statement could well be made at this Congress, although the 14 years intervening have been filled with activity, devising new methods, collecting data and increasing our understanding.

Recently, much attention has been paid to the pollution of coastal sea water with various hydrocarbons, which often give rise to a serious damage to the coastal fisheries in Japan. The present rezearch aims to elucidate components of hydrocarbon pollutants in relation to the source and mechanism of formation of so-called tar-balls floating on the surface of sea water. In the preliminary experiments, the hydrocarbon compounds in C-class heavy oil, wasted lubricant, and Iranian, Arabian and Minas crude oil samples were analyzed by gas chromatography (GLC). Then, each oil sample was floated in a test tank and allowed to settle on the surface of sea water for about 4 months, The n-paraffine components in each test sample were analyzed periodically. After standing for 400hr, the hydrocarbon components in the C-class heavy oil, wasted lubricant, Iranian and Arabian crude oil became indistinguishable form one another, while the Minas crude oil was distinctive from other oil samples. The n-paraffine components in tar-balls collected around Hachijo and Okinawa Islands were analyzed by GLC, and the source and mechanism of formation of such types of solid or semi-solid pollutants were discussed.

This paper discusses analytical and experimental results of a study on streamer formation, discharge waveforms, and RF noise levels. Measurements disclose typical pulse parameters as follows: rise time = 20 ns, discharge time = 80 ns, and pulsewidth < 600 ns (dependent upon test sample). A mathematical model is developed to represent electric field strength in the vicinity of the streamer with supporting measured values.

The caterpillars ofPieris brassicaeL. are used as test-insects in order to appreciate the efficacy ofBacillus thuringiensis preparations. A biological unity is used as a value of expressing the toxicity of these preparations. It is defined as the ratio between the L D 50 of a standard preparation and that of the test sample. In order to avoid the variation that occurs when the caterpillars have not always the same physiological conditions, a correction is made by using an ideal constant mortality curve of the standard preparation. This curve has been established on caterpillars being in very good physiological conditions.

Chromatographic separation of oestrone, 17β-oestradiol and oestriol on Sephadex G-10 A new assay is described to separate urinary oestrogens chromatographically. A 600 × 12 mm Sephadex G-10 column (Vt = 56.6 cm3) was loaded with samples up to 200 ml. Oestrogens and a few other urinary ingredients were reversibly adsorbed by the gel matrix if the test sample was saturated with Na2SO4 and adjusted to pH 4.6 ± 0.2. Almost all non oestrogenic urinary ingredients were eluted prior to the three sexual steroids which left the column in high purified fractions. As eluant a continuous non linear gradient was used produced by mixing a solution of 16% Na2SO4 with 0.1 N NaOH. An automatic oestrogen determination could be achieved by fluorometry in a flow cell. Additional extractions with organic solvents were unnecessary. 91.3% of the added radioactive oestrogens were discovered in the respective fractions.

The paper deals with the utilization of electron mirror microscopy for pictorial representation of the distribution of electrical conductivity. Previously described conductivity pictures obtained by this novel kind of electron microscopy have been of the normal two‐dimensional type; this paper reports three‐dimensional display of conductivity distributions. It discusses the concept of ``stereo‐micrographs of conductivity.'' It is shown that a three‐dimensional display of the conductivity distribution of thin films is possible by combining two electron mirror micrographs to a stereo‐pair. The two micrographs are distinguished solely by the amount of current passing through the specimen. As experimental evidence of the feasibility of three‐dimensional ``conductivity pictures'' a stereo‐micrograph of a test sample with artificially prepared areas of different conductivities is shown. Limitations and precautions to be observed are briefly discussed.

Summary In this study, the oiling-off properties of conventionally churned and continuously made butter 2 have been determined. Butter made by the continuous process had a consistently greater tendency to oil-off at 25 or 28° C. than did conventional butter. Seasonal variations throughout a 12-mo. period followed the same trend for both butter types, and were considerably greater within the type than the differences between corresponding samples of the two types. Maximum and minimum oiling-off occurred in June and October-November, respectively. This corresponds with the dates of minimum and maximum hardness of the butters of this region. The gas content did not influence oiling-off of the continuous butter, but gas content may contribute to stickiness. Oiling-off, when expressed quantitatively as weight-percentage of the original test sample, was found to be a function of the height of the test block of butter. Temperature, as well as grade and size of filter paper, also influenced the results.

The importance is emphasized of being able to differentiate between an increase in the power factor of a dielectric due to gaseous ionization and an increase due to other causes. The necessity of being able to detect discharges before they have caused sufficient damage to give rise to a change in power factor is also pointed out.A description is given of various methods of discharge detection which have been investigated, together with some details of the apparatus finally adopted and used.Methods for eliminating from the measurement all discharges external to the test sample are dealt with in some detail, this being an essential feature of apparatus for use onhigh-voltage testing circuits.The last section of the paper describes some of the practical uses of the apparatus.In the Appendices the various circuit arrangements are examined mathematically, and expressions are evolved for each method which provide the means of converting the readings obtained into the actual high-frequency current flowing in the dielectric.

A new zonal centrifuge rotor — the B-XXIII rotor — has been constructed that has tapered edge surfaces allowing a density gradient to be recovered either from the rotor edge or the rotor center. Experiments with a test sample containing bovine serum albumin and ragweed pollen grains showed only a small decrement in resolution when the rotor was unloaded from the edge instead of the center as is usually done. The removal of the outer portions of a gradient and the particles which it contains, and the reinsertion of a fresh gradient allow separation based on rate and on isopycnic banding density to be made sequentially in one rotor.

A description is given of a new instrument for measuring the lustre or gloss of a surface. Useful features of this instrument are: (1) that angles of incidence and reflection of the light can be varied over a wide range, thus allowing of very complete lustre curves being obtained; (2) the test sample need not be cut for measurement; (3) easy portability. Typical lustre curves are shown for a variety of surfaces and some of the results are briefly discussed. It is pointed out that the instrument can also be used as a spectrophotometer.

Two solutions are offered to the problem of distinguishing “historical” from “functional” associations in cross-cultural surveys. The underlying logic of the mathematical model is discussed and three kinds of association distinguished: hyperdiffusional or purely “historical” association, undiffusional or purely “functional” association, and semidiffusional or mixed “historical-functional” association. Two overland diffusion arcs constitute the test sample; the relationship of social stratification to political complexity constitutes the test problem. A sifting test establishes a bimodal distribution of interval lengths between like types and sifts out repetitions with a lesser interval length than the second mode. A cluster test shows that for the test problem, the “hits” cluster more than the “misses”.

The hardness test is one of the most useful and convenient physical tests which can be made on vulcanized rubber. It is easily made because the equipment can be simple, compact and portable. It is particularly useful in that the test sample may be a production article which can be put into service, undamaged, after the test. Consequently the test appears in the industry in several modifications, and the tester in diverse styles. Several more or less readily portable hardness testers are available commercially. The Shore Instrument and Manufacturing Co. has its line of Durometers, types A, B, C, D, etc.; Schopper, through Testing Machines, Inc., has marketed a tester similar to the Shore type A; the U. S. Gauge Co. has an instrument of the same type using the case of their pressure gage; the Firestone Penetrometer is another well-known tester of the spring-load type, as is the Adams Densimeter. At the present time the Society's Committee D-11 on Rubber Products is studying four portable hardness testers which are based on the specifications of the Standard Method of Test for Hardness of Rubber (D314-39), three of these being spring-operated instruments, the fourth, a dead-load type. In addition to the testers mentioned above, there is the Pusey-Jones Plastometer, which is a dead-weight hardness tester rather than a plastometer.

Summary Allocation of a profile to a predetermined group is normally made by the surveyor in the field but alternatively a computer can be programmed to process data and make the allocation. Differences arising from these procedures may be due to differences in either the information used by computer and surveyor or the rules used to analyse the data. There is a third method, in which the surveyor, using the same data as the computer, provides a link between the other two. Comparison, in general terms, of possible results from these three methods is supported by a study on profiles from the Riverina, N.S.W. Using data for a standard set of variables and allocating into one of three groups, misallocation of 4 per cent of a test sample of forty-six profiles resulted from both the computer method and the surveyor in the laboratory as compared with the surveyor's allocation of the same profiles on morphological properties in the field. This concurrence between the surveyor and the computer method allows the skill of the surveyor to be extended by way of the computer to technicians.

In the cases of whole test sample varieties, the number of cell layers has a close proportional relationship to the length of longitudinal diameter of the endosperm. Such proportional relationship is also observed, though somewhat less clearly than in the case of longitudinal diameter, in the cases of the dorso-ventral (breadth) and lateral (thickness) diameters of the endosperm, respectively. The number of cell layers and the length of longitudinal diameter show a remarkably varietal difference, and they are in inverse proportion to the number of cell layers and the length of breadth and thickness. The whole number of endosperm cells has no proportional relationship in general to the length of longitudinal diameter (or number of cell layers), except for very long endosperm varieties. The whole number of endosperm cells shows a high correlation to the 'size' which is represented by the product of longitudinal, dorso-ventral and lateral diameters, but it does not show any definite correlation to the 'shape' which is represented by the ratio between longitudinal and dorso-ventral diameters. In general, varieties distributed in the low latitude region, especially indica rice varieties which are cultivated preyalently maintly in India, etd. are long and thin in endosperm shape, small in size (volume), and less in number of cells. On the other hand, varieties distributed in high latitude regions, irrespective of North-east Asian or European areas, are shorter and thicker in endosperm shape, medium in size, and medium in the number of cells as well. In Africa and in a part of Europe, most of the varieties show a tendency to remarkably long and thin endosperm shape, very large size and to remarkably large number of cells. In the respective parts in these regions, it is noticed that the varietal differences in endosperm size, shape and number of cells are almost insignificant. However, only in the cases of varieties prevalent in Pacific island areas in South-eastern Asia, it seems to form exceptions, where it shows significantly great varietal differences in size, shape and in number of cells. It can be made clear that Japanese varieties' endosperm belongs to the shortest type in shape and to medium type in size because of their large thickness, thus these are grouped into the medium varieties in the number of cells.

Depending on heating rate, differences as large as 15°C in polymer transition temperatures may be observed in DCS measurements. A heat transfer analysis of the method shows that this rate dependence is a result of a lag in the heat path to the test sample and lag in heat transfer within the sample. Experiments confirmed the analysis. Methods for obtaining the correct values of transition temperatures are given.

Four alginate (irreversible hydrocolloid) impression materials certified as meeting A.D.A. specification 18 for hydrocolloid impression materials were tested for compatibility with five dental stones (20 tests). Five samples of each alginate-stone combination were made and evaluated (100 casts). The method of determining compatibility was a modification of the one given in A.D.A. specification 18 for dental hydrocolloid impression material. The principal changes from the test for compatibility with gypsum given in specification 18 are as follows: 1. The 0.025 mm. wide line produced by the stainless steel test block was used instead of the 0.075 mm. wide line for the evaluation. 2. Each test sample was scored 1, 2, 3, or 4 according to the quality of reproduction of the 0.025 mm. wide line. 3. Evaluation and scoring were accomplished under magnification (x10) using reproducible low-angle illumination. 4. Alginate impression materials and stones used in the study were mixed with a mechanical spatulator under reduced atmospheric pressure. The test casts were scored by four dentists on three successive days. An analysis of variance procedure was applied to the sums of the three replicates for each dentist. Di-Keen appeared to be more compatible with the impression materials tested than were the other stones; whereas, Jeltrate generally appeared to be more compatible with the dental stones tested than any of the other impression materials. The Di-Keen-Jeltrate combination appeared to be the most compatible combination, but it was not statistically better than the Di-Keen-D-P and Vel-Mix-Jeltrate combinations.

Some aspects of the protection of polymers against light degradation are discussed. (1) It is shown that the actually measured efficiency of light stabilizers depends very markedly on the brands of polymers used, on the preparation of the test sample, and on supplementary additives. (2) Two mechanistic conceptions are discussed on how u.v.-absorbers of the o -hydroxyphenyl type can dissipate their excitation energy. (3) As experiments show, the efficiency of u.v.-absorbers in thin samples and/or at low concentration cannot be explained by their filtering effect alone. (4) An empirical model is developed for the classification of the spectroscopic properties of u.v.-absorbers. (5) It is shown that the efficiency of esters of 4-hydroxy-3,5-di-tert-butylbenzoic acid as light stabilizers is not related to rate or yield of the photo-Fries-rearrangement of these compounds.

The purpose of this study was the development and validation of an instrument, the Behavior Preference Inventory (BPI), to measure the need values of special education administrators, utilizing Rotter's social learning theory. The five need categories of recognition-status, protection dependency, dominance, independence, and love and affection, were examined in an experimental test sample with which a validating instrument was used involving the administrator's subordinates. A normative sample involving membership of CASE contributed additional descriptive data. It is advocated that the BPI is useful as a screening device in related research on the relationship of need value to expectancy and situational determinants in decision making. It is also proposed that the instrument serve as a vehicle for the sensitization of administrators to their personality investment in decision making.

With respect to the printability of paper, several problems of color were investigated.Summary was as follows.(1) Max., min., and average qualities of each grade of printing Papers in Japan.(2) Inter relation of each other properties of paper testing figures of the middle class printing Paper.(3) Spectral reflect curve of the typical papers and pulps.(4) Effect of dyes on the paper color.(5) Effect of the kinds of color inks and paper qualities on the printing coloring effect.(6) Relation between paper testing values and theprinting coloring effect.Coloring effect was measured by means of comparing the spectral reHect curve of test sample with that of standard sheet printed under the standard condition.Calculation of the relation between A and B was done as follows.pA→B=SA (B) -a-1/b-1SC (B) /ST (B) -a (r-1) /b (r-1) SM (B)

A simple and reliable radiometric method for the determination of glucose-6-phosphatase (G-6-P-ase) activity in liver tissue is proposed. In principle, the method is based on the fact that, as a result of the action of the enzyme on C14-glucose 6-phosphate (C14-G-6-P), C14-glucose is formed. The undecomposed remainder of C14-G-6-P precipitates in the form of the barium compound. By comparing the activity of the supernatant of the test sample with the activity of the amount of C14-glucose equimolecular to that of C14-G-6-P prior to reaction, the quantity of C14-G-6-P broken down by the enzyme and, consequently, the activity of G-6-P-ase may be calculated.

periods of the life span. We know, for example, that the auditory ossicles and labyrinth are fully matured at birth, that the eyeballs and brain have almost reached adult size by five years, that the thymus and tonsils are at their greatest development and activity in childhood. The list might be indefinitely extended although along such lines we should but make generalizations without that directness of evaluation to which the method of study lends itself. It has been our good fortune during the past eighteen years to assemble a collection of human skeletons from known individuals for each of which it has been possible to secure the necessary data for a comprehensive study of growth and maturation, and of age changes in the remainder of the life span so far as these are set forth in the bones. This series has now reached the comparatively large total of eighteen hundred individuals including more than two hundred children and young people. In addition the roentgenographic study of a test sample of over one thousand children gives us opportunity to check the observations made both by the X-ray and by dissection or maceration on our skeletons.

At a dilution of 1:200.000, and in the presence of excess sulfuric acid, as little as 0.2 μg nitrate ion forms a yellow color with chroniotropic acid. Interfering colors due to nitrites and oxidizing agents are eliminated by previous treatment of the test sample with sodium sulfite, sulfuric acid, and sulfamic acid.

The complete course of the vulcanization curve is obtained by measuring the values of the dynamic shear modulus during a period while the test sample is held at the vulcanization temperature. The measurements are made about the position of zero distortion. The curves are in good agreement with those obtained by a step-cure method, and scorch data agree well with those obtained with the Mooney apparatus. The method has the following advantages and disadvantages. A. Advantages 1) The course of the vulcanization curve is established on a single sample without curing in stages. 2) Minimum material is required. 3) The test is quickly performed. 4) Good reproducibility is observed. 5) The unit lends itself readily to automatic recording so that one man can easily operate several instruments. B. Disadvantages 1) The apparatus should be operated by trained workers. 2) The cost of the apparatus is rather high.

A convenient technique is presented for determination of triboelectric characteristics of a film sample relative to a group of reference surfaces and to other film samples, with the use of inexpensive, easily assembled equipment. It consists of pressing a number of reference surfaces into contact with a test film, determination of the sign and intensities of the charges generated, by spraying with an indicating powder, and estimation of tribo-electric position of the test sample by the distribution of positive and negative charges generated. With this technique, relative triboelectric characteristics were determined for films of various polymers. The measurements give some insight into the relation between polymer structure and triboelectric characteristics.

Shattered, mealy curd, sediment on the bottom of the vat, and slow acid production were associated with agglutinating strains of Cottage cheese cultures. Agglutinated bacteria formed centers of high acid production and resulted in dense flecks of acid-precipitated casein. These flecks either settled as a sediment or were trapped during coagulation and caused a fragile, mealy curd. The sediment was low in pH and high in protein and bacteria. Acid production in the supernatant skimmilk was retarded through displacement of agglutinated bacteria to the bottom of the vat, indicating that agglutinating antibodies in skimmilk are not inhibitory, per se. Prolonged agitation of skimmilk and starter promoted agglutination and, after agitation ceased, resulted in more sediment and reduced rates of acid production. With agglutinating cultures, the pH of the A-C test sample, receiving less agitation, reduced more quickly than skimmilk in the vat, thereby nullifying the test as a direct indicator of the time to cut the curd. Heating skimmilk (71 C/30min) or removing agglutinins by adsorption on heat-killed cells eliminated the defects. Pasteurization (72 C/16sec) reduced the agglutinating activity of skimmilk by 50–75%. Agglutinating strains differed markedly in the severity of defects produced; two strains settled so extensively that the skimmilk did not coagulate; whereas, defects with some strains were evident only as small amounts of sediment. Auto-agglutination of certain strains also appeared to cause small amounts of sediment. Some commercial cultures contained agglutinating strains and produced sediment. Selection of agglutination-resistant strains for Cottage cheese cultures is recommended.

The uses of the outer walls of the right ventricles of guinea pigs and of auricles of rabbits for the assay of digitalis have been reinvestigated. The results obtained are compared with those obtained by slow intravenous infusion in guinea pigs (B.P. 1958) and the pigeon method (U.S.P. XV). The results obtained by the use of isolated auricles indicate that this method is reasonably accurate, cheap and less time-consuming than other methods and has the further advantage that the test sample is compared with the standard on the same tissue.

This paper deals with the strength of rock-like materials under triaxial stress conditions. The most common theories of brittle fracture are reviewed. Some methods of triaxial strength determination are described and the results compared. The strength dependence of lateral pressure, pore pressure and size of the test sample is described. Some standard tests are suggested. A method for determining the shear strength at high normal pressure has been used as a measure of the strength of a number of Swedish rocks and ores.

The Allen and Ridley method for the isolation of parasitic ova from sewage sludge was modified by the addition on an anionic detergent to an increased test sample. This method was equally efficient for counting Ascaris lumbricoides ova in raw sludge and in various mixtures of sludge and compost. The modified method yielded considerably higher counts for all samples studied than the original method.

The amount of 1-tryptophane excreted per day by 9 different normal male subjects was determined by a microbiological method with L. arabinosus as the test organism. From 12-30 mg per day were excreted as contrasted to an average value of 281 mg per day reported by Albanese and Frankston. A negligible amount of indole in the urine could be demonstrated. Satisfactory values and recoveries of 1-tryptophane were obtained at different levels of the test sample.

A variant of the oxygen index flammability test has been developed which, used in conjunction with the candlelike determination, contributes to a truer understanding of the flammability of materials. This test is entitled the Bottom Ignition Oxygen Index (B.I.O. I.) and is run by igniting the bottommost surface of the test sample rather than the upper most surface as in the normal, candlelike determination. It is shown that the high, e.g., 27 or more, candlelike Oxygen Index (O.I.) of certain materials is not an adequate indi cation of flame retardance. These materials can be completely consumed in an alternative flammability test and afford much lower O.I. when tested in the bottom ignition manner. A useful criterion for flame retardance appears to be a candlelike O.I. of at least 27 in addition to a B.I.O.I. of at least 22.

A simple method, which requires virtually no change in the Fibrograph, is described for converting the instrument to automatic operation by the use of a servo system. The accessories required are rugged and are commercially available. Smoother fibrogram curves are obtained by this method, and less time is required because the operator is free to comb the next test sample while a fibrogram curve is being drawn.

The Schaal or Oven Test, originally developed by the biscuit and cracker industry to provide a relative rating for stability of various shortenings, has been generally adopted by shortening manulacturers. Advantages as well as limitations of the test are enumerated. It is possible to estimate the Oven Test by determining peroxide development in the test sample after two to four days in the oven. Oven Tests may also be conducted without having determined them organoleptically by observing the color change at the point of extreme rancidity. Peroxide formation occurring in a fat contained in biscuits or crackers when subjected to the Oven Test has been investigated and a simple and rapid method of extracting the fat, without changing its peroxide characteristics, has been devised.

points of the pathogenic organisms that may render milk dangerous have been determined with precision in many laboratories and that an actual exposure to 60 C. for 20 minutes would suffice to kill such nonspore-bearing organisms as B. diphtheriae, B. tuberculosis and B. typhosus voiced the general conclusion of all who had worked on this subject. Although the practical application of these facts to the pasteurization of large volumes of milk was another problem, exposure to this temperature, for the time given, had been uniformly considered as adequate, and this aspect of the subject was looked on as closed. Recently, however, Twiss2 has reopened the subject and used bacteria of the typhoid-paratyphoid group as test organisms. Her contention is that, in actuality, the temperatures of pasteurization are inadequate; that the method of using small samples of the heated milk for the determination of the death of the bacterium present does not exclude the possibility of the survival of a few organisms. She asserts that if the whole test sample (100 c c) be incubated it will not infrequently be found that a few bacilli have survived exposure to 60 and even to 65 C. for 30 minutes.

1. In the macroscopic resazurin test, an quality inspection of milk could be done by the “one hour test” in which the color change was divided into 7 degrees.2. When 1cc of 1% formalin was added to a test sample, the reduction time was shortened and it took almost 15 min. for a milk sample containing about four million bacteria to reduce resazurin pigment. From this result, this reduction time could be used as a practical standard for the inspection of the quality of milk.3. When oxygen was eliminated from a sample by the Thumberg vacuum tube, the reduction time was shortened remarkably. From the results of redox-potential experiments, it would seem that the re duction of pigment was due to the deterioration of redox-potential caused by oxygen censumption of bacteria.4. Lactose in milk had little reductive ability of resazurin pigment.

An all-glass aeration tube and improved air-distributing apparatus are described for use in the Swift stability test or similar accelerated method of determining stability of fats. A procedure is described in which only one tube is required for each test sample. By this procedure, it is possible to carry out as many stability tests simultaneously on one standard apparatus as on three such units by the usual three-tube method. Observations on the use of adaptations of Wheeler’s method of determining peroxide values are reported. The effects of air, time of reaction, size of sample, and quantities of reagents were investigated.

The resistance of highly conductive materials is measured by an induction method that does not require a direct electrical connection to the test specimen. Instead, the test sample is used as a short‐circuited secondary winding of a transformer. The method is suited to specimens where lead correction errors would introduce difficulty, or where the temperature or field environment requires that the sample be located at some distance from the instruments. Resistances of the test specimen from 10−5 to 10−2 Ω are suitable for this method. It has been applied to determining the resistance of hard superconductors at 4.2° and at frequencies of 100 to 30 000 cps. Various niobium‐zirconium alloys all followed a characteristic resistivity curve with ρ proportional to f0.5 at high frequencies and ρ proportional to f1.7 at f

A Complexonometric method has been developed for determining cerium in organic compounds such as the acetylacetonate, benzoate, or toluate; the method is based on extraction of the cerium by hydrochloric acid and Complexonometric titration in the presence of xylenol orange indicator. The method gives good precision of results; the mean square error is +0.63% abs. or 2.21% rel. with a metal content of about 28% in the test sample. The cerium determination by this method requires not more than 20 to 30 min, in comparison with 10 h by the gravimetric method.

99mTc-DTPA preparations were analyzed using an abbreviated two-column chromatographic system. Separate columns of Sephadex/saline and alumina/acetone were utilized in sequence to separate 99mTc-DTPA from both 99mTcO4- and “hydrolyzed-99mTc.” Control studies showed that small Sephadex columns do remove “hydrolyzed-99mTc” from a test sample, alumina is capable of binding 99mTc-DTPA, and neither column has an affinity for 99mTcO4-. The mini column approach has the potential for use as a routine quality control test method.

Scores on the Airfield Layout test may be strongly affected by random and systematic error, as indicated by fairly low internal consistency, demonstrated effects of certain circumstances of administration, and pronounced effect of the order in which the examinee undertook task requirements. However, basic scoring points appear fairly comprehensive and sound. In the test sample of several hundred, statistically significant correlation should be possible, despite attenuation, with any variables having substantial representation of abilities required in reporting on airfield sites or determining needed length of runway.

An instrument capable of measuring the resistance of a complete mandibular denture to dislodgement in the vertical and the horizontal planes was constructed. Measurements were made on seven patients wearing platinum-cobalt magnetic implant dentures. These measurements were compared to the average retention and stability measurements obtained from thirty conventional denture-wearing patients. The results of the study indicate that: 1. 1. The strength of individually packaged sets of magnets varies considerably from set to set. The platinum-cobalt magnets in the magnet strength test samples had a vertical resistance mean of 84.52 Gm. The platinum-cobalt magnets sampled had a horizontal resistance mean of 33.58 Gm. 2. 2. The retention of the average conventional complete mandibular denture in a test sample of 30 patients was 250 Gm. The stability of the average conventional complete mandibular denture in a test sample of 30 patients was 150 Gm. 3. 3. The addition of magnets to a denture may increase the resistance to dislodgment vertically by a mean of 193 Gm. The addition of magnets to a denture may increase the resistance to dislodgement in a horizontal direction by a mean of 103 Gm.

A 576-round firing test was conducted to determine the cause of the high dud rate of Cartridge, 40mm, HE: M406 (Lot MA-10-63) with Fuze, M551 (Lot MHR-20-3). Twenty-four dud projectiles were recovered and disassembled. Inspection of the fuzes revealed eight unarmed, seven partially armed, two with defective firing pins, and seven with indentations in their detonators. The overall dud rate of the 576 rounds was 4.34%. There is no significant dif ference between the dud rate of the test sample and the acceptance criteria.

An assay-plate assembly has been described to be used in tissue culture for screening solid materials for toxicity, as well as for testing the cytotoxicities of various liquids such as antibiotics, anticancer agents and miscellaneous chemicals. This apparatus, in which the test sample is completely immobilized and is in direct contact with the cell monolayer, can be used for testing objects of any shape or density.

This report presents the results of two series of tests on the electrical simulation of nuclear transients which were performed In the High Voltage Laboratory of the Westinghouse Electric Corporation East Pittsburgh Works. The first test series determined that temperature measurements were not required in transient testing of graphite samples with a pulse of 0.016 second duration. The second series disclosed deficiencies in the experimental equipment. A new design of test sample holder is proposed and a tentative schedule for additional tests Is offered.

The purpose of this project is to determine the thermal properties of explosives, and to continue the development and evaluation of thermal tests. Two preliminary experiments were conducted to determine (1) how the time-to-explosion (TE) using Lee Plugs (short stainless steel and aluminum) would compare with the TE obtained using the lead plugs; and (2) how the Lee Plugs would perform with du Pont`s EL-511 and Tacot at 314{degrees}C and 362{degrees}C., respectively. The Pantex-built chromatograph is operating as a two-column instrument, and the findings of an extensive check out of the instrument are reported. The chemical reactivity test sample holders were shown to evolve approximately 30{mu}l of N{sub 2} + O{sub 2} and 3 {mu}l of CO{sub 2} when heated for 22 hours. A number of thermal tests were made on two lots of LX-04-1 (39A and 38B) to determine if any differences could be detected that would explain why Lot 38B tensile strength is much better than 39A when both were made from the same lot of Viton A. Some differences were detected, but they have not been related to the tensile strength of the material. The time-to-explosion for various Adiprenes with HMX are reported, and they indicate that there could be some reactivity between the Adiprene and HMX. Pantex and LASL DTA thermograms and pyrolograms for PETN and Extex are reported for comparison to determine how the sensitivity of Pantex instruments compare with LASL, and if these instruments could be used to qualify PETN and Extex in accordance with LASL Specification 13Y-104481.

The report documents results of an 18-month study program to develop improved methods for case bond structural analysis. The study was limited to unflawed bond systems in solid propellant rocket motors. In Task I of the program, parametric stress solutions were obtained for cylindrical motor configurations with flapped and right-angle bond terminations. In Task II of the program, improved test sample configurations were developed for the measurement of case bond tensile and shear strength. Based on results obtained from this program, techniques for the assessment of case bond integrity have been placed on a level equivalent to existing techniques for the assessment of grain integrity at the centerport.

A new device that can be used as a light modulator as well as an optical directional coupler is proposed. It consists of p+,n,n+,n and n+‐type semiconductor layers. Two n‐type layers operate as coupled optical waveguides. The exchange of light power between two coupled waveguides can be controlled by a reverse voltage applied on the p+‐n junction. When the voltage was changed from 0 to 10 V in a GaAs test sample of length 1 mm, the output light power from each guide changed by approximately 15% of the total output light power from the two guides at a wavelength of 1.15 μm.