Porous aluminum oxide layers may be obtained by anodic oxidation in sulphuric acid. The base of the pores is separated from the metal by a thin insulating barrier layer. The experiments show that the ultimate thickness of the barrier layer remains constant after a critical value has been reached. The dependence of the final thickness on current density, concentration, and temperature has been investigated. It is suggested that an electronic current is involved in the mechanism which limits the growth of the barrier layer.
{"title":"ON THE CAPACITY OF POROUS ALUMINUM OXIDE LAYERS","authors":"A. Dekker, Helen M. A. Urquhart","doi":"10.1139/CJR50B-065","DOIUrl":"https://doi.org/10.1139/CJR50B-065","url":null,"abstract":"Porous aluminum oxide layers may be obtained by anodic oxidation in sulphuric acid. The base of the pores is separated from the metal by a thin insulating barrier layer. The experiments show that the ultimate thickness of the barrier layer remains constant after a critical value has been reached. The dependence of the final thickness on current density, concentration, and temperature has been investigated. It is suggested that an electronic current is involved in the mechanism which limits the growth of the barrier layer.","PeriodicalId":9392,"journal":{"name":"Canadian journal of research","volume":"97 1","pages":"541-550"},"PeriodicalIF":0.0,"publicationDate":"1950-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"80811155","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
The Arndt–Eistert reaction offers a convenient method for the synthesis of the higher members of the aliphatic carboxylic acid series. Nonadecanoic acid, eicosanoic acid, and heneicosanoic acid have been prepared successively from stearic acid in good yields. An efficient method of purification of the synthetic products is described. The ultraviolet absorption maxima for some diazoketones derived from the higher members of the aliphatic carboxylic acid series are recorded.
{"title":"THE APPLICATION OF THE ARNDT–EISTERT REACTION TO THE SYNTHESIS OF FATTY ACIDS OF HIGH MOLECULAR WEIGHT","authors":"F. A. Vandenheuvel, P. Yates","doi":"10.1139/CJR50B-067","DOIUrl":"https://doi.org/10.1139/CJR50B-067","url":null,"abstract":"The Arndt–Eistert reaction offers a convenient method for the synthesis of the higher members of the aliphatic carboxylic acid series. Nonadecanoic acid, eicosanoic acid, and heneicosanoic acid have been prepared successively from stearic acid in good yields. An efficient method of purification of the synthetic products is described. The ultraviolet absorption maxima for some diazoketones derived from the higher members of the aliphatic carboxylic acid series are recorded.","PeriodicalId":9392,"journal":{"name":"Canadian journal of research","volume":"27 1","pages":"556-560"},"PeriodicalIF":0.0,"publicationDate":"1950-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"82941358","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
The averages and ranges for thiamine in approximately 250 samples of cereals tested, expressed as μgm. per gm., were: barley 4.2 (3.3–5.7), oats 6.7 (3.8–8.6), wheat 4.5 (3.4–5.9); for riboflavin: barley 1.3 (0.9–1.6), oats 1.3 (1.0–1.7), wheat 1.2 (1.0–1.4). There was a marked increase in the thiamine content of oats over that for 1946—amounting to 0.7 μgm. per gm. Barley and wheat showed slight increases. The values for riboflavin in the three cereals grown in 1947 were about the same as those for the 1946 samples. Varietal effects on thiamine content differed somewhat from those observed in 1946. For barley, Garton, OAC21, Sanalta, and Montcalm were about equal and slightly better than Plush. The order of thiamine content of wheat—for those varieties of which more than 10 samples were tested—was Carlton, Regent, Redman, Thatcher, and agreed with the findings for the previous year. Durum wheats showed higher thiamine levels than spring wheats. There was no varietal effect on the thiamine content of oats...
{"title":"The thiamine and riboflavin content of Manitoba grown wheat, oats, and barley of the 1947 crop.","authors":"A. D. Robinson, C. Tobias, B. J. Miles","doi":"10.1139/CJR50F-030","DOIUrl":"https://doi.org/10.1139/CJR50F-030","url":null,"abstract":"The averages and ranges for thiamine in approximately 250 samples of cereals tested, expressed as μgm. per gm., were: barley 4.2 (3.3–5.7), oats 6.7 (3.8–8.6), wheat 4.5 (3.4–5.9); for riboflavin: barley 1.3 (0.9–1.6), oats 1.3 (1.0–1.7), wheat 1.2 (1.0–1.4). There was a marked increase in the thiamine content of oats over that for 1946—amounting to 0.7 μgm. per gm. Barley and wheat showed slight increases. The values for riboflavin in the three cereals grown in 1947 were about the same as those for the 1946 samples. Varietal effects on thiamine content differed somewhat from those observed in 1946. For barley, Garton, OAC21, Sanalta, and Montcalm were about equal and slightly better than Plush. The order of thiamine content of wheat—for those varieties of which more than 10 samples were tested—was Carlton, Regent, Redman, Thatcher, and agreed with the findings for the previous year. Durum wheats showed higher thiamine levels than spring wheats. There was no varietal effect on the thiamine content of oats...","PeriodicalId":9392,"journal":{"name":"Canadian journal of research","volume":"278 1","pages":"341-350"},"PeriodicalIF":0.0,"publicationDate":"1950-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"90785312","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
The calorimetric method of measuring sources is of value when the average energy per disintegration is known, and may be used to check the accuracy of an "absolute" beta counting technique. This paper describes a differential calorimeter designed for this type of measurement, and an experimental determination of the disintegration rate of a P32 source. The calorimetric measurement gave a value of the disintegration rate with a probable error of 0.7% differing by 1.8% from the result obtained from an absolute count of the β-activity. The absolute count was accurate to ±2%. The calorimeter has a sensitivity limit of less than 10 μw., and makes use of thermistors to measure temperature changes of the order of 10−3 °C.
{"title":"A CALORIMETRIC MEASUREMENT OF THE DISINTEGRATION RATE OF A P32 SOURCE","authors":"J. Bayly","doi":"10.1139/CJR50A-042","DOIUrl":"https://doi.org/10.1139/CJR50A-042","url":null,"abstract":"The calorimetric method of measuring sources is of value when the average energy per disintegration is known, and may be used to check the accuracy of an \"absolute\" beta counting technique. This paper describes a differential calorimeter designed for this type of measurement, and an experimental determination of the disintegration rate of a P32 source. The calorimetric measurement gave a value of the disintegration rate with a probable error of 0.7% differing by 1.8% from the result obtained from an absolute count of the β-activity. The absolute count was accurate to ±2%. The calorimeter has a sensitivity limit of less than 10 μw., and makes use of thermistors to measure temperature changes of the order of 10−3 °C.","PeriodicalId":9392,"journal":{"name":"Canadian journal of research","volume":"93 1","pages":"520-529"},"PeriodicalIF":0.0,"publicationDate":"1950-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"84688219","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
The measurement of the energy distribution of fission fragments has been extended to include fragments from fission in Pu239. The same equipment was used as in previous experiments on U235 and U233. The experimental results parallel very closely those obtained in the previous work. The values obtained for the most probable energies for the light and heavy fragments from Pu239 are 94.6 and 65.2 Mev. respectively. The statistical accuracy of the data is, as before, an improvement over earlier work in this field, and a more detailed comparison of the three materials is made possible.
{"title":"ENERGY DISTRIBUTION OF FISSION FRAGMENTS FROM Pu239","authors":"D. C. Brunton, W. Thompson","doi":"10.1139/CJR50A-040","DOIUrl":"https://doi.org/10.1139/CJR50A-040","url":null,"abstract":"The measurement of the energy distribution of fission fragments has been extended to include fragments from fission in Pu239. The same equipment was used as in previous experiments on U235 and U233. The experimental results parallel very closely those obtained in the previous work. The values obtained for the most probable energies for the light and heavy fragments from Pu239 are 94.6 and 65.2 Mev. respectively. The statistical accuracy of the data is, as before, an improvement over earlier work in this field, and a more detailed comparison of the three materials is made possible.","PeriodicalId":9392,"journal":{"name":"Canadian journal of research","volume":"103 1","pages":"498-508"},"PeriodicalIF":0.0,"publicationDate":"1950-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"84910674","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
With a view to testing the adequacy of the perturbation theory as applied to radiationless transitions in light atoms, the probability of such a transition in the Be atom from the 1s22p3s3P state to the continuum 1s22s + ejected p electron has been calculated. The wave functions employed for the discrete states are obtained by the variational method and the wave function for the continuous state by numerical integration of the Schrodinger equation. The transition probability obtained is 5 × 1013 per second, leading to a width of ~ 290 cm.−1 for the level 1s22p3s3P. This is at least 103 times larger than what is indicated by the observed widths of the spectral lines. Thus the present calculation, together with similar earlier calculations for the He atom, shows that the perturbation theory is inadequate for the light atoms.It is also pointed out that there is an inconsistency in the use of the perturbation theory in these calculations and those on the Auger effect in the literature since the use of variati...
{"title":"PROBABILITY OF AUTO-IONIZATION IN LIGHT ATOMS","authors":"Ta-you Wu, Lorraine Ourom","doi":"10.1139/CJR50A-045","DOIUrl":"https://doi.org/10.1139/CJR50A-045","url":null,"abstract":"With a view to testing the adequacy of the perturbation theory as applied to radiationless transitions in light atoms, the probability of such a transition in the Be atom from the 1s22p3s3P state to the continuum 1s22s + ejected p electron has been calculated. The wave functions employed for the discrete states are obtained by the variational method and the wave function for the continuous state by numerical integration of the Schrodinger equation. The transition probability obtained is 5 × 1013 per second, leading to a width of ~ 290 cm.−1 for the level 1s22p3s3P. This is at least 103 times larger than what is indicated by the observed widths of the spectral lines. Thus the present calculation, together with similar earlier calculations for the He atom, shows that the perturbation theory is inadequate for the light atoms.It is also pointed out that there is an inconsistency in the use of the perturbation theory in these calculations and those on the Auger effect in the literature since the use of variati...","PeriodicalId":9392,"journal":{"name":"Canadian journal of research","volume":"38 1","pages":"542-548"},"PeriodicalIF":0.0,"publicationDate":"1950-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"86862863","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
The velocity of sound in pure helium gas has been measured as a function of pressure at −78°, 0°, 50°, 100°, and 200 °C., using an ultrasonic interferometer of the double crystal type. From the sound velocity data second viral coefficients were obtained, and the ratio of specific heats was derived as a function of pressure.
{"title":"THE VELOCITY OF SOUND IN HELIUM AT TEMPERATURES −78 °C. TO 200 °C. AND PRESSURES UP TO 70 ATMOSPHERES","authors":"W. Schneider, G. Thiessen","doi":"10.1139/CJR50A-041","DOIUrl":"https://doi.org/10.1139/CJR50A-041","url":null,"abstract":"The velocity of sound in pure helium gas has been measured as a function of pressure at −78°, 0°, 50°, 100°, and 200 °C., using an ultrasonic interferometer of the double crystal type. From the sound velocity data second viral coefficients were obtained, and the ratio of specific heats was derived as a function of pressure.","PeriodicalId":9392,"journal":{"name":"Canadian journal of research","volume":"37 1","pages":"509-519"},"PeriodicalIF":0.0,"publicationDate":"1950-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"90617617","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Leveling Bulb Control for Null Manometers","authors":"J. Arnell, G. O. Henneberry","doi":"10.1139/CJR50F-032","DOIUrl":"https://doi.org/10.1139/CJR50F-032","url":null,"abstract":"","PeriodicalId":9392,"journal":{"name":"Canadian journal of research","volume":"38 1","pages":"361-362"},"PeriodicalIF":0.0,"publicationDate":"1950-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"72975181","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Using the well known methods of statistical mechanics, partition function ratios for many isotopic sulphur compounds have been calculated. These partition function ratios are used to determine equi...
利用众所周知的统计力学方法，计算了许多同位素硫化合物的配分函数比。这些配分函数比率用于确定相等的。
{"title":"THERMODYNAMIC PROPERTIES OF ISOTOPIC COMPOUNDS OF SULPHUR","authors":"A. Tudge, H. Thode","doi":"10.1139/CJR50B-069","DOIUrl":"https://doi.org/10.1139/CJR50B-069","url":null,"abstract":"Using the well known methods of statistical mechanics, partition function ratios for many isotopic sulphur compounds have been calculated. These partition function ratios are used to determine equi...","PeriodicalId":9392,"journal":{"name":"Canadian journal of research","volume":"20 1","pages":"567-578"},"PeriodicalIF":0.0,"publicationDate":"1950-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"84916545","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
A special specimen holder has been constructed for the evaporation of metals within an RCA–EMU electron microscope. This provides continuous observations on the growth of films of the metal. Micrographs are reproduced which illustrate the formation of films of silver, gold, and tin. The results confirm the usually accepted assumptions regarding the formation of nuclei and the growth of aggregates.
{"title":"CONTINUOUS OBSERVATIONS WITH THE ELECTRON MICROSCOPE ON THE FORMATION OF EVAPORATED FILMS OF SILVER, GOLD, AND TIN","authors":"T. McLauchlan, R. Sennett, G. D. Scott","doi":"10.1139/CJR50A-043","DOIUrl":"https://doi.org/10.1139/CJR50A-043","url":null,"abstract":"A special specimen holder has been constructed for the evaporation of metals within an RCA–EMU electron microscope. This provides continuous observations on the growth of films of the metal. Micrographs are reproduced which illustrate the formation of films of silver, gold, and tin. The results confirm the usually accepted assumptions regarding the formation of nuclei and the growth of aggregates.","PeriodicalId":9392,"journal":{"name":"Canadian journal of research","volume":"35 1","pages":"530-534"},"PeriodicalIF":0.0,"publicationDate":"1950-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"75508922","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
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