bluuebunny/crossref_metadata_2025 huggingface dataset:
AN AIR-BASE STEREOSCOPE
Authors: Field R. H.
Published: April 2011

Three magnifying stereoscopes, intended for orienting stereo pairs of vertical air photographs and then ruling in the directions of the projections of the air bases on the photographs, were designed and constructed in the National Research Laboratories for the Department of Mines and Resources. Some features found useful in previously designed photogrammetric instruments were incorporated.
NOTES ON THE TESTING OF SEXTANTS
Authors: West G. O.
Published: April 2011

In World War II a shortage of manners' sextants resulted in the collection by the Royal Canadian Navy of used sextants from various sources. These were, as far as possible, reconditioned and verified by the National Research Laboratories, Ottawa. For this work, and for calibrating new sextants, some modifications were made to the collimator system regularly employed for the verification of angle-measuring instruments. A brief description is given of the apparatus and of the procedure developed for testing sextants, together with a few remarks on sextant errors.
DRIED WHOLE EGG POWDER: XXI. PASTEURIZATION OF LIQUID EGG AND ITS EFFECT ON QUALITY OF THE POWDER
Authors: Gibbons N. E. , Fulton C. O. , Reid Margaret
Published: April 2011

Heating liquid egg to 60 °C. reduced the viable bacterial count 85 to 95% but had less effect on the coliform organisms. Holding the liquid at 60 °C. for 30 min. reduced the viable count 98 to 99%, and destroyed the coliforms, Salmonella, and Staphylococci. Quality tests indicated no difference between powders prepared from heated and unheated melange either originally or after storage. Tests with a laboratory flash pasteurizer indicated that a considerable reduction in the number of total viable and coliform organisms occurred when liquid egg was heated from 22° to 60 °C., the total time in the pasteurizer being approximately one minute.
THE PREPARATION OF HEXACHLOROETHANE IN THE LIQUID PHASE BY CHLORINATION OF TETRA—AND PENTACHLOROETHANE
Authors: Pearce Jesse A.
Published: April 2011

Preliminary investigations showed a slow rate of production of hexachloroethane from chlorine-saturated liquid tetrachloroethane. The addition of some materials that often accelerate similar reactions was not effective here. However, rapid production was obtained by chlorinating tetrachloroethane in the presence of ultra-violet light. The effective wave-lengths appeared to lie between 3150 Å and 3540 Å, and the temperature coefficient between 75° and 100 °C. was 1.10. The result indicated that production of hexachloroethane from chlorine-saturated liquid tetrachloroethane was feasible. For the same conditions of illumination and temperature hexachloroethane was produced from chlorine-saturated pentachloroethane at a rate two and one-half times as fast as that in chlorine-saturated tetrachloroethane.
A CLINOMETER FOR MEASURING SMALL ANGLES
Authors: Field R. H.
Published: April 2011

The paper describes a clinometer for the accurate measurement of angles of elevation or depression up to 5° from the horizontal. The geometrical design permits a theoretical precision of ± 2″ to be attained in this range on a uniformly divided micrometer head without the application of corrections or the use of cams or associated devices. While the instrument can be read to 1″ and is sensitive to about twice this amount, no special tools or jigs were needed for its construction, beyond the equipment ordinarily available in a small machine shop.
LIQUID AND FROZEN EGG: III. SOME FACTORS AFFECTING THE QUALITY OF STORED FROZEN EGG
Authors: Pearce Jesse A. , Reid Margaret
Published: April 2011

Liquid from eggs of various qualities packaged in Reynold's Metal A-10 and liquid from Grade A eggs in wax paper with and without added ice was frozen at −40° F. and stored at 10°, 0°, and −10° F. for 12 months. Examination of baking properties and changes in pH, fluorescence, and reducing sugar content indicated the desirability of using liquid from Grade A eggs, although liquid from Grade C and cracked eggs may also be satisfactory; and of limiting the storage period for frozen egg, stored at these temperatures, to about six months. It was also desirable to allow the frozen egg to age for a month or two before use; and to use a highly moisture resistant barrier at all storage temperatures, although the wax paper and ice combination may be satisfactory at 0° and −10° F. Reducing sugar content decreased with an increase in the number of bacteria and, in addition, this measurement appeared to be a good indication of the quality of liquid and frozen egg.
THE DIFFUSION LENGTH OF THERMAL NEUTRONS IN HEAVY WATER CONTAINING LITHIUM CARBONATE
Authors: Hereward H. G. , Paneth H. R. , Laurence G. C. , Sargent B. W. , Munn A. M.
Published: April 2011

The density distribution of thermal neutrons was measured with a small boron trifluoride chamber in a cylindrical tank containing 113 litres of heavy water in which lithium carbonate was dissolved. The diffusion length was found to be 22.7 cm. in this solution containing 7.70 × 10−4 atoms of lithium per molecule of heavy water (99.4 atom % D). After corrections were applied for the capture of neutrons in the heavy water and light hydrogen, the capture cross-section of lithium was found to be 59 × 10−24 cm.2 per atom for neutrons of standard velocity 2200 m. per sec. from the measured diffusion length and known transport mean free path.
THE CALCULATION OF LINE STRENGTHS FROM LABORATORY DATA
Authors: Petrie William
Published: April 2011

A. S. King has made extensive intensity estimates of spectral lines in furnace and are spectra, and these data provide useful material for determining line strengths. The estimates have been made for many elements of astrophysical interest, and are reduced to line strengths for FeI, TiI, and TiII.
A NOTE ON PHASE CORRECTION IN ELECTRICAL DELAY NETWORKS
Authors: Ferguson Alex. J.
Published: April 2011

The standard method of correcting the phase characteristic of low-pass networks by introducing mutual inductance between the coils is extended. By means of mutual inductance between the coils and a capacity across them, it is possible to eliminate the third and fifth order terms in the variation of the phase shift with frequency. The relation required between the circuit constants for this result is given, and is found to be very simple.
THE RATIO OF THE CAPTURE CROSS-SECTIONS OF LITHIUM AND BORON FOR THERMAL NEUTRONS
Authors: Fenning F. W. , Seligman H. , Graham G. A. R.
Published: April 2011

A small boron trifluoride chamber is used to obtain the spatial distribution and density integrals of thermal neutrons produced by a source in aqueous solutions of compounds of lithium and boron. The effects of the finite size of the boron chamber are minimized by adjusting the concentrations of the solutions so that the mean life of thermal neutrons is the same in both. The scattering mean free paths are also almost identical. The final result is[Formula: see text]Taking σB = 705 × 10−24 cm.2 per atom, σLi = (66.8 ± 1.0) × 10−24 cm.2 per atom.
THE FOUNDATIONS AND PHILOSOPHICAL IMPLICATIONS OF WAVE MECHANICS
Authors: Shu Seyuan
Published: April 2011

This paper attempts to show:(a) The nature of the basic assumptions made either explicitly or implicitly by L. de Broglie in arriving at the fundamental formula, [Formula: see text], of wave mechanics, and that at least some of these assumptions are open to criticism.(b) That it is a little too hasty to regard as demonstrated the non-localization of photons or electrons in motion and the lack of determinism with respect to them.(c) That the presuppositions which lead to the 'relations of incertitude' involve highly arbitrary elements and these 'relations' are read into or arbitrarily imposed upon the physical world rather than really found to be in it.(d) That it is an unwarranted claim that the new mechanics can contribute to the solution of the age-long philosophical problem of free will.(e) That it is possible to render the foundations of wave mechanics logically independent of the theory of relativity.
SPATIAL DISTRIBUTION OF NEUTRONS IN HYDROGENOUS MEDIA CONTAINING BISMUTH, LEAD, AND IRON
Authors: Munn A. M. , Pontecorvo B.
Published: April 2011

The spatial distributions of thermal neutrons (as measured by dysprosium detectors) and of resonance neutrons (indium detectors protected by cadmium) have been investigated in several media, consisting of water and heavy elements in a heterogeneous arrangement, with two different neutron sources (Ra-α-Be and Ra-γ-Be). The experimental results are summarized in tables where the values of the mean square distances from the source of neutrons are given, for the various media, detectors, and sources used. It was found that among all the media investigated, a mixture of water and iron is the most efficient shield for neutron generating machines such as piles and cyclotrons.
THE EFFECT OF WIND ON THE THERMAL RESISTANCE OF CLOTHING WITH SPECIAL REFERENCE TO THE PROTECTION GIVEN BY COVERALL FABRICS OF VARIOUS PERMEABILITIES
Authors: Larose P.
Published: April 2011

The thermal resistance of a pile fabric uncovered and covered with thin fabrics of various permeabilities was measured under different conditions of wind velocities and wind direction. Wind velocities up to 30 m.p.h. were used and tests were carried out with winds striking the surface of the material at 0°, 30°, 45°, and 90°. The permeabilities of the covers varied between 0 and 193 cu. ft. per sq. ft. per min., under a pressure difference of [Formula: see text] in. of water across the fabric. The effects of varying the conditions of the thermal resistance of the boundary air layer are discussed and corrections applied to the results for the resistance of this air layer. The results show that for low wind velocities, the permeability, within wide limits, is relatively of little importance, but with higher wind velocities it is advantageous to employ a covering fabric of as low a permeability as possible.
THE GAMMA-RAY MEASUREMENT OF RADIUM ORE CONCENTRATES
Authors: Hushley W. J. , Dixon W. R.
Published: April 2011

A method is described for measuring the radium content of substances in which the radium concentration is of the order of micrograms per gram of material. The gamma-ray activities of the unknown material and of a standard radium capsule are compared by means of Geiger-Müller counters. Corrections for self-absorption and distance are given for rectangular and cylindrical sources. The effect of radiation scattered by the source into the detector is discussed. Synthetic bulk sources made up with known quantities of radium were used for the experimental work.
A THEOREM ON NEUTRON MULTIPLICATION
Authors: Placzek G. , Volkoff G.
Published: April 2011

The asymptotic behaviour of the neutron distribution due to a point source in an infinite homogeneous medium in which a convergent chain reaction (multiplication constant k<1) takes place is investigated without special assumptions about the properties of the medium and the mechanism of neutron diffusion. It is shown under very general assumptions that at large distances r from the point source the neutron distribution always has the form[Formula: see text]General expressions for the constants μ and A of this asymptotic form of the distribution are given for any k<1 in terms of the Fourier transform of the spatial distribution of primary fission neutrons. These expressions reduce to particularly simple form for (1 − k) << 1. The exact expression for the neutron distribution throughout the medium is given in integral form. Four special frequently occurring cases are discussed as illustrations of the general result.
EXCITATION CONDITIONS IN THE UPPER ATMOSPHERE AS DETERMINED FROM A STUDY OF ATOMIC EMISSION LINES IN THE AURORAL SPECTRUM
Authors: Petrie William
Published: April 2011

Vegard's identifications of a number of lines appearing in the auroral spectrum are discussed. The conclusion is reached that a good many of these lines may be attributed to the oxygen atom in several stages of ionization. It is shown how measured line intensities and theoretical line strengths are combined to give the excitation temperature of the auroral region. Preliminary results indicate that this temperature is in the range 3000° to 6000° K. The meaning of this result is discussed briefly.
THE USE OF DIAPHRAGMS IN THE ELECTRON MICROSCOPE
Authors: Ellis S. G.
Published: April 2011

A method is described for deducing electron trajectories from optical measurements made on the electron microscope. A device for centring and changing apertures while the microscope is in operation is described. The choice of the size and position for diaphragms is discussed, together with other factors involved in their use.
THE SYNTHESIS AND THE CHARACTERIZATION OF MONOMETHYL- AND DIMETHYLINDOLES
Authors: Marion Léo , Oldfield Catharine Woolsey
Published: April 2011

All the seven monomethylindoles and 18 of the 21 possible dimethylindoles have been synthesized by unambiguous methods. Eleven were prepared by the Fischer ring closure applied to the appropriate phenylhydrazone, five of which through the appropriate phenylhydrazone of ethyl pyruvate. The rest were prepared by the Tyson ring closure. The picrates of each indole and the styphnates of all but three were prepared and their properties recorded. The three unrecorded styphnates (those of 1,6-, 5,6-, and 5,7-dimethylindole) could not be isolated without decomposition although they seemed to exist in solution.
THE SYNTHESIS OF DI- AND TRITHIOLS
Authors: Simpson S. D.
Published: April 2011

In the course of a study of antidotes to lewisite the following thiols have been prepared from the corresponding di- and trihalides by the action of sodium hydrosulphide or ammonium hydrosulphide in ethanol under pressure: 1,2-dimercaptoethane, 1,2-dimercaptopropane, 1,3-dimercaptopropane, 1,2,3-trimercaptopropane, 1,2-dimercapto-n-butane, 2,2′-dimercaptoethyl ether, 3,3′-dimercaptopropyl ether, 2,2′-dimercaptoisopropyl ether, and 1,3-dimercapto-2-propanol.1,2-Dimercaptopropane has been prepared by a new method, namely, by the interaction of ammonium hydrosulphide and allyl bromide. This method involves the addition of hydrogen sulphide to an unsaturated compound by the action of ammonium hydrosulphide in ethanol under pressure.The toxicity of the above thiols and their antidotal activity to lewisite have been compared with those of 2,3-dimercaptopropanol (BAL, British anti-lewisite) and the results of these studies will be published later.
CATALYTIC AROMATIZATION OF TURNER VALLEY CRUDES
Authors: Graham W. , Hutcheon A. T. , Spinks J. W. T.
Published: April 2011

The maximum yield of toluene resulting from catalytic aromatization of a selected cut from Turner Valley crude oil has been determined. Using a catalyst containing 14% chromium trioxide on aluminium trioxide and a temperature of 515 °C., a total yield of toluene equal to 3.15% by weight of the original crude may be obtained. This is 137% greater than the quantity of toluene originally present in the crude (1.33%). A possible recovery of approximately 250,000 lb. of toluene per day is indicated for the whole Turner Valley field (1942).
THE FLOW PROPERTIES OF SOME ANHYDROUS SODIUM SOAPS
Authors: Southam F. W. , Puddington I. E.
Published: April 2011

The flow properties of anhydrous sodium stearate have been followed in some detail over the temperature range 45° to 140 °C., using an extrusion plastometer. Comparative results have been obtained at a single temperature with the sodium soaps of some of the lower fatty acids. The results indicate large changes in the properties of sodium stearate at 68° and 105 °C. An abrupt change is also observed when the number of carbon atoms in the soap is reduced below eight.
A NOTE ON THE USE OF MULTI-TIP ELECTRODES IN POLAROGRAPHIC WORK
Authors: McGilvery J. , Hawkings R. C. , Thode H. G.
Published: April 2011

In the past, a dropping mercury electrode for polarographic work has consisted of a single capillary dipping in a solution. We have used two or more capillaries in parallel to increase cathode surface and thereby increase the diffusion current and the sensitivity of the instrument. The results indicate that each tip gives a diffusion current proportional to its calibration constant and that multi-tip electrodes give diffusion currents proportional to the sum of the capillary constants. Further, galvanometer oscillations are reduced considerably by the use of multi-tip electrodes. The use of multi-tip electrodes, therefore, makes it possible to extend the limits of detection and provides a means for reducing objectionable galvanometer oscillations.
A METHOD OF ANALYSIS FOR THE SYSTEM: BENZENE – ETHYL ALCOHOL – CARBON TETRACHLORIDE
Authors: Campbell A. N. , Miller S. I.
Published: April 2011

The densities and refractive indices (Nc) of binary and ternary mixtures of benzene, ethyl alcohol, and carbon tetrachloride have been determined at 25 °C. From these data, a method for the analysis of ternary liquid mixtures of these components has been developed. The limit of accuracy in the analysis of ternary mixtures of the pure components is 0.3%. The method can be applied to the analysis of commercial materials with an accuracy of 2.0%.
THE PREPARATION, PURIFICATION, PHYSICAL PROPERTIES AND HYDROLYSIS OF CYANOGEN CHLORIDE
Authors: Douglas D. E. , Winkler C. A.
Published: April 2011

Cyanogen chloride, prepared by the method of Jennings and Scott, has been fractionally recrystallized to a constant freezing point of −6.90 °C. Vapour pressure values for material purified in this way are in good agreement with the data of Klemenc and Wagner. The activation energy for the hydrolysis of cyanogen chloride at pH 4 to 6 between 0° and 50 °C. is approximately 21 kcal. per mole.
STUDIES ON THE FORMATION OF HEXAMINE
Authors: Boyd Mary L. , Winkler C. A.
Published: April 2011

Rate curves have been determined for the reaction of ammonia and formaldehyde in aqueous solution at 0 °C. and 35 °C., over a range of initial mole ratios (formaldehyde: ammonia) of 0.25 to 2.0. For each set of conditions, three curves have been obtained on the basis of ammonia consumed, formaldehyde consumed, and material precipitated with mercuric chloride respectively.At 0 °C. the three rate curves tend to approximate one another in a large excess of ammonia but are widely separated in excess formaldehyde. The reverse is true at 35 °C. The reaction is characterized by a high initial rate of formation of hexamine, this rapid rate being maintained to a lower yield of hexamine the more dilute the solution. The existence of a stable by-product in excess formaldehyde is indicated by the variation in final yields of hexamine, when these are calculated on the basis of formaldehyde consumed, ammonia consumed, or material precipitated with mercuric chloride.A mechanism for the reaction has been suggested.
THE KINETICS OF CONSECUTIVE SECOND ORDER REACTIONS
Authors: Potter C. , Macdonald W. C.
Published: April 2011

A study of consecutive competitive second order reactions is reported. It is shown that identical equations can be obtained by two different approaches. A static method is described where equations are developed by considering the changes brought about in the system by the addition of small quantities of one of the reactants. Equations are also developed from the point of view of kinetics. These equations express the concentrations of the products as functions of the concentration of one of the reactants and the ratio of the velocity constants.
THE ADSORPTION OF ALIPHATIC ACIDS ON ACTIVATED CHARCOALS
Authors: Lemieux R. U. , Morrison J. L.
Published: April 2011

The adsorptions of acetic, propionic, butyric, and valeric acids from aqueous solutions on a series of coconut charcoals of different degrees of activation were determined. For purposes of interpretation the numbers of millimoles adsorbed per gram of charcoal were compared for pairs of acids. Unimolecular adsorption of the acids is indicated. Surface areas of the charcoal series were estimated. They range from 130 to 625 sq. m. per gm. of charcoal, depending on the adsorbate used and the degree of activation of the charcoal. Some insight into the activation process is given.
PHOTOMETRIC MICRODETERMINATION OF CALCIUM
Authors: DeLuca H. A.
Published: April 2011

A method is described for the photometric determination of amounts of calcium ranging from 0.04 to 0.16 mgm. The calcium is precipitated as the oxalate. The latter is converted to the carbonate by heating at 475° to 500 °C. for one hour. The carbonate is dissolved in 1 ml. of 0.01 N hydrochloric acid. The excess acid is allowed to liberate iodine by reacting with potassium iodate and potassium iodide. The absorption of the iodine solution is measured by use of an Evelyn colorimeter, and the calcium originally present in the sample is determined from calibration data.
QUANTITATIVE ESTIMATION AS ACETIC ACID OF ACETYL, ETHYLIDENE, ETHOXY, AND α-HYDROXYETHYL GROUPS
Authors: Lemieux R. U. , Purves C. B.
Published: April 2011

Kuhn and L'Orsa's method for estimating terminal methyl and similar groups was based on the recovery of the acetic acid formed when such units were oxidized with hot concentrated chromic acid solution. The method has now been reduced to the semimicro scale and refined to the point where good analyses for acetyl, ethylidene, ethoxy, and α-hydroxyethyl groups in a variety of substances are obtained. Acetylated triphenylmethyl cellulose ethers, which do not seem amenable to customary acetyl analyses, give good results by the present procedure.
STUDIES ON THE CLADOSPORIUM BLIGHT OF SWEET PEA
Authors: Good H. M.
Published: April 2011

Following the appearance of the Cladosporium blight of sweet pea in Ontario in 1945, a study of the causal organism and the disease was carried out. As a result of this study the name Cladosporium album Dowson has been retained for the organism in preference to Erostrotheca multiformis Martin and Charles, or Hyalodendron album (Dows.) Diddens. Temperature and humidity studies have indicated that the parasite and the disease develop most rapidly at 25 °C., and that high humidity is necessary for infection and for fruiting on the leaf. Penetration is stomatal, without appressoria, and occurred 10 times as often into leaves with 'open' as into leaves with 'closed' stomata. Evidence that C. album may show a positive hydrotropism was obtained. Frequency of penetration increased with an increasing gradient around the stomata, and this was interpreted as evidence that hydrotropism is a factor in penetration. Host range studies and a comparison of frequency of penetration into an immune and a susceptible species showed frequent penetrations into the immune species but no appreciable development in any but sweet pea.
AEROBIC BACTERIA THAT DECOMPOSE CELLULOSE, ISOLATED FROM QUEBEC SOILS: I. ISOLATION AND DESCRIPTION OF THE SPECIES
Authors: Alarie A. M. , Gray P. H. H.
Published: April 2011

Soil bacteria that hydrolyze starch were isolated by means of an elective culture medium with this polysaccharide as the sole source of carbon; their ability to decompose cellulose was then tested. Thirteen strains of cellulose decomposing bacteria were thus isolated from several Quebec soils. The bacteria have been assigned to three recognized genera under eight new specific names. Their elevation to species rank is based on differentiations comparable to those used in Bergey's Manual. The following new species have been proposed: Vibrio perimastix, Vibrio hyperion, Bacterium infirme, Bacillus vagans, Bacillus Kellermani, Bacillus soli, Bacillus torquens, and Bacillus effluens.
STUDIES ON THE DECOMPOSITION OF CELLULOSE BY MICRO-ORGANISMS
Authors: Perlin A. S. , Michaelis M. , McFarlane W. D.
Published: April 2011

The metabolism of an impure culture of an aerobic cellulose decomposing bacterium, Vibrio perimastix, was studied. The products of cellulose decomposition included carbon dioxide, a pigment resembling riboflavin, a bacterial polysaccharide, and traces of acid. Carbon dioxide was found to be essential for the decomposition of cellulose and could not be replaced by calcium carbonate. Increasing the carbon dioxide content of the air above 1.2% retarded growth on a glucose medium.Respiration studies were carried out using cellulose, glucose, and cellobiose as substrates, and the possible role of the latter two as intermediates in cellulose decomposition was investigated. Glucose was produced from cellulose when toluene was added to cultures during active decomposition; evidence is presented that a dialyzable factor produced by the bacteria is essential for glucose formation. Phosphorylation inhibitors prevented growth of the bacteria on cellulose, glucose, and cellobiose, inhibited respiration of active cellulose cultures, and retarded the production of glucose by toluene-treated cultures. Cellulose treated with alkali to increase the proportion of amorphous to crystalline cellulose was more rapidly decomposed than untreated cellulose.
STUDIES ON THE LIFE HISTORY OF TRICHOCEPHALUS VULPIS, THE WHIPWORM OF DOGS
Authors: Miller M. J.
Published: April 2011

Under experimental conditions fully embryonated eggs of Trichocephalus vulpis hatch in the small intestine of dogs within 30 min. after the eggs are fed. The larvae penetrate the intestinal mucosa within 24 hr. after infection and at that time may be found deeply embedded. Between 48 and 96 hr. after infection the larvae become coiled and sluggish, and the majority are found lying at the base of the crypts of Lieberkühn in the upper levels of the small intestine. They do not work their way back to the lumen of the intestine for at least eight days, although there is some evidence that they may return to the lumen by the 10th day after infection and are then carried passively down to the large intestine. There is some minor tissue destruction by the larvae during their mucosal penetration.
THE R.C.A.M.C. ELECTROMYOGRAPH MARK III
Authors: Jasper Herbert H. , Forde William O.
Published: April 2011

The R.C.A.M.C. Electromyograph Mark III is an apparatus developed under the auspices of the National Research Council of Canada during the war for the study of casualties with peripheral nerve injuries. It was used principally to study the electrical activity of muscles as a sensitive test of their nerve supply and general condition with regards to atrophy, etc. It is now being used not only in the diagnosis and to follow the recovery of nerve injuries, but for the study of muscle activity in various neuromuscular diseases, including poliomyelitis.The electromyograph consists of (a) a high gain, low noise level, wide range calibrated, balanced, push–pull pre-amplifier, with built-in calibrator, (b) a cathode ray oscilloscope unit with photographic attachment, and incorporating a nerve and muscle stimulator of variable intensity and duration, and (c) a mobile loud speaker cabinet including the speaker power amplifier, battery, and battery charger.Action potentials from single muscle fibres, or groups of fibres known as the motor unit, are picked up by means of a small finely pointed needle electrode, insulated except at the very tip, thrust through the skin into the muscle. A reference electrode is placed on the skin next to the point of insertion of the needle and a distant grounded electrode is placed on the subject to aid in the elimination of stray electrical interference. Action potentials are then amplified through four stages of condenser coupled amplification. They are then of sufficient magnitude to be clearly observed or photographed on the calibrated screen of the cathode ray oscilloscope, which makes possible accurate measurement of each potential wave, both in voltage and duration. The sound of the muscle action potentials may be simultaneously heard in the loud speaker. With training, diagnosis of muscle conditions may be greatly aided by certain characteristic sounds produced by different kinds of muscle activity.For example, a denervated muscle gives rise, from single muscle fibres, to continuous low voltage random 'spikes' that produce in the loud speaker a 'crackling' sound recognized as fibrillation. At rest the normal muscle is electrically silent. It gives rise during contraction to action potentials that are much higher and of longer duration. They produce in the loud speaker a knocking sound recognized as a motor unit discharge. During recovery from a nerve injury, and in certain degenerative conditions, the motor unit becomes poorly synchronized or disintegrated producing very complex wave forms that produce a distinctive 'chugging' sound.The electrical stimulator, which is synchronized with the trace of the oscilloscope, makes it possible to test the responsiveness of single muscles to different forms of electrical current as well as to record the electrical activity of a given muscle in response to stimulation of its motor nerve at a distance. By the use of the same equipment, the nerve impulse can also be followed in its course down the nerve fibre.
THE ESTIMATION OF TRYPSIN
Authors: White F. D. , Bowman J. M.
Published: April 2011

Details are given of a colorimetric method for the estimation of trypsin that can be utilized for the evaluation of the proteolytic activity of pancreatic secretion. Being an adaptation of a method that has been used successfully in a clinical laboratory for many years, it is suitable for routine clinical use. Like Anson's method it depends upon the colour reaction between the tyrosine–tryptophane radicals of a protein substrate and Folin's phenol reagent, but embodies the following features: the results cannot be influenced by the presence of peptidases in the enzyme solution, since the procedure is based upon the estimation of a casein substrate before and after digestion, and not upon the digestion products; the digestion is carried out at 37 °C.; by reference to a curve the enzyme content can be expressed in terms of trypsin nitrogen. Results obtained with this method showed a reasonable degree of constancy, the average deviation from the mean being ±3.3% and the maximum deviation, ±8.4%.
THE PULMONARY FUNGUS, HAPLOSPORANGIUM PARVUM, AND ITS RELATIONSHIP WITH SOME HUMAN PATHOGENS
Authors: Dowding Eleanor Silver
Published: April 2011

In a survey of the wild rodents of Alberta it was found that 14 animals contained within their lungs fungous cells so large as to be visible to the naked eye. From the lungs of eight of these infected animals, Haplosporangium parvum was obtained in culture. The position of the fungus among the Phycomycetes is confirmed by a study of the reproductive structures, which may be interpreted as sporangia containing one or, rarely, several spores. H. parvum grows and sporulates upon soil. The sporangia are adhesive and transferred by contact. At 37 °C. they enlarge as much as 10 times their original diameter to form thick-walled chlamydospores that will germinate at room temperature. The parasite within the lung has a diameter as much as 50 times that of the sporangium from which it must have originated. Infected lungs usually show little reaction. Only one lung was frankly granulomatous. Some human systemic Phycomycetes, like H. parvum, are filamentous in their saprophytic phase and unicellular in their parasitic phase. Three of them, Blastomyces dermatiditis, B. brasiliensis, and Histoplasma capsulatum, are closely related to H. parvum. In their saprophytic phase they all reproduce by adhesive conidia that may be interpreted as sporangia with single endospores, while in their parasitic phase no sporangia have been observed. Coccidioides immitis is less closely related to H. parvum. When growing saprophytically it reproduces by air-borne oidia; when growing parasitically, by endospores.
THE NON-AVAILABILITY OF LYSINE FROM THE CORRESPONDING HYDANTOIN IN THE RAT
Authors: Page Edouard , Gaudry Roger , Gingras R.
Published: April 2011

The hydantoin of lysine was fed to rats on a lysine-free diet and was shown to have no growth promoting effect. This hydantoin, therefore does not appear to give rise to the corresponding α-amino acid in contrast with results obtained elsewhere with diphenylhydantoin in man and dog.
DRIED MILK POWDER: VII. THE EFFECT OF SEASON OF PRODUCTION ON KEEPING QUALITY
Authors: Pearce Jesse A. , Bryce W. A.
Published: April 2011

Milk powders of 1% butterfat content, produced in the fall of the year, had higher initial palatability scores than similar powders prepared in the spring.. The skim milk powders from fall milk decreased in quality throughout a storage period of 16 wk. at temperatures of 80°, 100°, or 120° F. Similar powders from spring milk stored at 80° F. increased in quality throughout the storage period while those stored at 100° and 120° F. first increased and then decreased in quality. Powders of 26 or 28% butterfat, produced in the spring or in the fall, had equal initial palatability scores and when stored deteriorated equally. Fail milk powder containing 30% butterfat was better initially than the comparable spring sample, but, when stored, quality changes in both types were about equal. At each storage temperature all whole milk powders deteriorated at about the same rate.
FLAVOUR REVERSION IN HYDROGENATED LINSEED OIL: III. THE RELATION OF ISO-LINOLEIC ACID TO FLAVOUR DETERIORATION
Authors: Lemon H. W.
Published: April 2011

Further evidence that iso-linoleic acid is related to the unpleasant odour development when partially hydrogenated linseed oil is heated is as follows:(a) Partially hydrogenated perilla oil, containing considerable iso-linoleic acid, developed the same odour when heated, as did partially hydrogenated linseed oil.(b) A concentrate of iso-linoleic acid developed a similar odour when it was heated. Distillation of the acid, or removal of unsaponifiable substances, had no effect on the odour development.(c) When fatty acid fractions obtained by crystallization of the acids from hydrogenated linseed oil were re-esterified with glycerol, and subjected to the heat test, most odour development occurred in the fraction containing most iso-linoleic acid.Increasing the selectivity of hydrogenation did not greatly affect the formation or hydrogenation of iso-linoleic acid. However, products of high temperature (200° to 250 °C.) hydrogenations were softer for equivalent iodine numbers, and had lower melting points than those from low temperature hydrogenations.Hydrogenation of partly polymerized linseed oil yielded a product that when heated did not develop the characteristic odour of hydrogenated linseed oil.
CHARACTERISTICS OF CANADIAN LARD
Authors: Lips H. J. , Grant G. A.
Published: April 2011

Mean values for measured properties of 33 samples of lard obtained from 26 packing plants across Canada were: iodine number, 58.7; saponification number, 193.9; melting point, 43.5 °C.; smoke point, 382° F.; colour, 8.8Y, 1.6R; unsaponifiable matter, 0.43%; fatty acid composition: saturated, 45.6%, oleic, 44.7%, linoleic, 8.7%, linolenic, 0.6%, arachidonic, 0.4%; storage life at 26.7 °C., 9.2 weeks; Swift stability, 3.5 hr.; iodimetric peroxide, 1.6 ml. of 0.002 N thiosulphate per gm.; ferrometric peroxide, 9.7 m.e. per kgm.; Kreis test, 9.9; Stamm test, 2.3; alpha-dicarbonyl test, 3.4; free fatty acid, 0.4%; fluorescence, 79.2. The distribution of values is shown by histograms.Simple correlation coefficients computed between measured properties showed the following to be associated: melting point with iodine number; free fatty acid content with melting point, smoke point, and red colour; storage life at 26.7 °C. with log of Swift stability and initial ferrometric peroxide, Kreis, and alpha-dicarbonyl values.
THE FRICTION OF HEATED SLEIGH RUNNERS ON ICE
Authors: Pfalzner P. M.
Published: April 2011

An attempt was made to reduce the sliding friction of sleigh runners on ice at 20° F., 0° F., and −10° F. by applying heat to the runners. The efficiency of this method was found to be less than 20%. Some doubt is thrown on the simple theory that the low friction on ice is due to a lubricating film of water.
AN APPARATUS FOR THE BUTT-WELDING OF FINE WIRES
Authors: Armstrong L. D. , Dauphinee T. M.
Published: April 2011

A butt-welding apparatus employing a condenser discharge is described. This apparatus was developed for welding thermocouples of small dimensions but is suitable for most types of fine wires. The welding characteristics and possible applications are given in detail.
A LABORATORY SHAKER
Authors: White W. Harold
Published: April 2011

A laboratory shaker is described that employs an eccentricless drive. The machine has sufficient flexibility in design to permit variable temperature and speed control. It has a capacity of two dozen 500-ml. flasks.
A LARGE CYLINDER AND TAPER COMPARATOR FOR GAUGE MEASUREMENT
Authors: Field R. H.
Published: April 2011

The measurement of the diameters of cylinders and cones is an important feature in gauge manufacture and inspection. High accuracy is essential in this work, as the objects measured may be employed as limit gauges for use in the inspection of other precision gauges to which direct means of measurement cannot be applied. A comparator for accommodating cylinders or cones with maximum diameters of 12 in. and lengths up to 48 in. was designed and constructed during Great War II at the National Research Laboratories, Ottawa, and used throughout the war. In preparing the design special consideration was given to ease of construction and no ultra precision grinding or difficult fits were involved.
THE OXIDATION, IGNITION, AND DETONATION OF FUEL VAPORS AND GASES: I. A REACTION CHAMBER ADAPTED TO DETERMINE THE EFFECT OF ANTIKNOCKS ON THE RAPID OXIDATION OF FUEL VAPOR AT HIGH TEMPERATURES
Authors: King R. O.
Published: April 2011

Slow combustion experiments by conventional laboratory methods show that metallic dopes such as the iron and nickel carbonyls and tetraethyl lead act as antioxidants in respect of the liquid paraffins present in engine fuel, the effect being especially marked at high temperatures. Such an effect failed to account for the results of certain engine experiments which could be interpreted only on the assumption that the metallic dopes promoted oxidation of the 'end gas' which is known to be the seat of knock.The inconsistencies mentioned justified an investigation of conventional laboratory methods of measuring rate of oxidation. This led to the design of a small scale flow method reaction chamber in which a typical paraffin, such as pentane, containing iron carbonyl in small concentration and mixed with air in combining proportions could be oxidized to final products, without explosion, in a time of exposure of one second or less at temperatures rising to 700 °C. Oxidation of the doped pentane was to the final products, carbon dioxide and steam, at all temperatures of reaction, rate of formation of carbon monoxide being barely measurable. On the other hand, the oxidation of pentane alone was accompanied by a profuse liberation of aldehyde, reaching a maximum rate at about 400 °C. and giving a negative temperature coefficient of reaction over the range 400° to 500 °C. Oxidation of the pentane alone occurred at a much lower rate, over the high temperature range, than when it contained iron carbonyl in the usual small proportion ([Formula: see text] of 1%).The new reaction chamber was used less successfully in demonstrating the effect of tetraethyl lead to promote the oxidation of pentane owing to difficulties arising from the properties of lead. A measurable promoting effect was, nevertheless, obtained at all temperatures of reaction.The text has been restricted to an account of the development of a novel type of reaction chamber and to oxidations of pentane necessary for the purpose. The chamber is of more general application.
A NOTE ON AN OMNI-DIRECTIONAL ARRAY OF STACKED V-ANTENNAS
Authors: Pepper T. P.
Published: April 2011

An omni-directional antenna array, which might find use in the frequency-modulation broadcast field, is described.
THE THERMAL CONDUCTIVITY OF NAPALM–GASOLINE GELS
Authors: Langstroth G. O. , Zeiler F.
Published: April 2011

A slightly modified form of the rapid and simple method suggested by Hutchinson for the measurement of the thermal conductivity of liquids has been found to suffer from convection effects with samples of low viscosity, except with conductivity tubes of very small diameter. For more viscous liquids such as glycerol it was found to be adequate under all conditions studied. The method has been applied in the determination of the conductivity of Napalm–gasoline gels. For temperatures T between − 50° and 50 °C., and Napalm concentrations C between 0 and 10%, the conductivity k in cal. sec.−1 cm.−1 per degree C. is described to better than 1% by the relation, k × 105 = 29.7 − 0.068 T + 0.11 C. The temperature coefficient of resistance of the unaged tungsten filaments used in the tubes differed considerably from the value given by the International Critical Tables for aged tungsten filaments. For temperatures T0 between − 50° and 50 °C., the coefficient α0 per degree C. is given to better than 1% by the relation, [Formula: see text].
A SIMPLIFIED BROADSIDE DIPOLE ARRAY
Authors: Bell J. H.
Published: April 2011

A broadside dipole array, or 'billboard', with a greatly simplified feed and matching system, is described. Radiation patterns compare favorably with those of the conventional billboard.
STUDIES IN HIGH FREQUENCY DISCHARGES
Authors: Lodge J. I. , Stewart R. W.
Published: April 2011

A qualitative theory of the nature of high frequency discharges, with special reference to those developed by the use of external sleeve electrodes, is advanced on the assumption that the discharge is largely determined by its d-c. wall and space charges, and that the chief function of the high frequency field is to maintain the electron temperature. This theory leads to the conclusion that there must be a high negative wall charge under the electrodes, and a high radial field tending to drive positive ions to the walls. Thus each electrode has many of the characteristics of a cathode in a d-c. discharge. This conclusion is verified by the appearance of the high frequency discharge and by a careful examination of deposits resulting from the removal, by positive ion bombardment of the tube wall, of thin metallic films and of materials of which the discharge tube itself is composed.
THEORETICAL STUDY OF RAM-JET PROPULSION
Authors: Szczeniowski Boleslaw
Published: April 2011

In ram-jet propulsion, artificial compression before combustion does not exist. Therefore, the only factors which may influence the increase in momentum, i.e., the thrust, are:(1) The degree of initial dynamic compression by a diffuser;(2) The shape of the combustion chamber;(3) The variations of the rate of heat release along the tube;(4) Air excess coefficient;(5) Kind of fuel;(6) Velocity of flight;(7) Aerodynamic and heat losses.This paper deals almost exclusively with the first four factors, i.e., with the theoretical case of an ideal gas and a perfect flow, with no heat or aerodynamic losses involved. The possible appearance of shock waves is disregarded. Neither are boundary layer phenomena discussed in this paper. The external fairing and the relation between the internal and external shape, as well as the influence of this relation on the actually obtainable thrust and efficiency, are also considered to be beyond the scope of the paper. General conclusions are drawn as to the optimum shape of the ideal engine from the standpoint of efficiency. It is found that air should be submitted initially to as high a dynamic compression as possible, i.e., using all kinetic energy available, after which a combustion chamber of constant cross section is used—and finally a nozzle. Another conclusion is that it is impossible to obtain a positive thrust with a combustion chamber of constant cross section, if no dynamic compression, by a diffuser, is initially applied. Special attention is drawn in the paper to the representation and interpretation of the ideal ram-jet cycle on the entropy diagram, this giving a clear picture of the relations between the energy released and the efficiency and thrust obtainable. The fact that in the flow through a tube of constant cross section with heat release (e.g., by combustion), the pressure may decrease even if ideal gas and perfect flow (with no losses involved) are concerned, is emphasized throughout the paper, as it seems that generally this fact is rather overlooked.
GAMMA RAYS FROM THE DISINTEGRATION OF BORON BY SLOW NEUTRONS
Authors: Rose B.
Published: April 2011

The slow neutron disintegration of B10 yields two groups of α-particles, corresponding to the production of Li7 in either the ground state or an excited state. The γ-radiation accompanying the de-excitation of the excited nucleus was studied. Boron in the form of boron trifluoride in a proportional counter was irradiated with slow neutrons from a Ra–α–Be source. Coincidences were counted between α-particle pulses in the proportional counter and γ-ray pulses in an adjacent Geiger–Müller counter. The ratio of the α–γ coincidence rate to, the α-rate gave the product of the efficiency of the Geiger–Müller counter and the number of quanta emitted per boron disintegration. The absorption coefficient of the γ-radiation in lead was measured, and, by comparison with the absorption coefficients for the γ-radiation from Cu64 and Au198, the energy was found to be 0.48 ± 0.015 Mev. The quantum efficiency of the Geiger–Müller counter for radiation of this energy was determined by calibration with standard sources of Co60 and thorium active deposit. Hence the number of quanta per boron disintegration was found to be 0.90 ± 0.08, in satisfactory agreement with the value to be expected from the relative abundance of the α-particle groups from this reaction.
ATTEMPT TO DETECT AN (n,2n) REACTION IN DEUTERIUM
Authors: Elliott L. G. , Hincks E. P. , May A. N.
Published: April 2011

A detailed account is given of experiments carried out to detect an (n,2n) reaction in deuterium. A Po-α-Be neutron source was surrounded by a hollow aluminum sphere 30 cm. in diameter, which could be filled with heavy water. The sphere was surrounded by an effectively infinite medium of paraffin oil. The neutron density distribution outside the sphere was measured with a small boron trifluoride chamber (6 mm. diameter × 20 mm. long). The total integrated densities of neutrons were determined both with the sphere empty and filled with heavy water. After correcting for absorption of thermal neutrons by the heavy water, the aluminum sphere, and the source, and of fast neutrons by the oxygen of the heavy water, it is shown that the fraction of neutrons giving an (n,2n) effect is 0.1 ± 2.7%. This indicates that the effect is less than both that predicted by Höcker's theory (~ 10%) and that reported from an earlier experiment by Halban and coworkers (18%). However it is in good agreement with measurements made by Fenning and Knowles (1.4 ± 5%).
THE DENSITY OF ADSORBATES
Authors: McIntosh R. L. , Maass O. , Tuck N. G. M.
Published: April 2011

The apparent density of the adsorbate and the adsorption isotherm have been measured in the systems carbon tetrachloride – charcoal and diethyl ether – charcoal. In both, the apparent density of the adsorbate is lower than the normal liquid density. These abnormally low values cannot be explained on the basis of the coexistence of 'vapor' and 'liquid' adsorbed phases. The results are consistent with the concept of the adsorbatc's blocking-off a portion of the internal voids of the charcoal. The Langmuir equation represents the isotherm only when the quantity adsorbed exceeds two-thirds of the saturation value. The Harkins–Jura equation is valid at low relative pressures in the carbon tetrachloride – charcoal system, but not in the diethyl ether – charcoal system. Neon is adsorbed appreciably on charcoal at 25 °C. and therefore cannot be employed to examine the effect that the gas being used for the measurements has on the apparent density of the adsorbate. Until more accurate data are available for the adsorption of helium on charcoal, both in the absence and presence of other adsorbates, the density of charcoal and the density of the adsorbate measured by helium displacement remain suspect. In view of the uncertainties, the utility of apparent density values of adsorbates in checking the concepts of the various theories of physical adsorption is limited.