No accurate description of the red and infrared portion of the arc spectrum of silicon has been published in the 40 years that have elapsed since Rowland's work which terminated at 5,948 A. In this paper, wave lengths are given for 130 new lines between 6,125 and 11,290 A, many of which are present in the solar spectrum, including the strongest hitherto unidentified Fraunhofer line. More than 50 percent of these lines have been classified as combinations between new terms and terms already established for Si I. The new terms arise from the electron configurations containing the 4p, 4/, and 5/ electrons.
{"title":"ARC spectrum of silicon in the red and infrared","authors":"C. C. Kiess","doi":"10.6028/JRES.011.054","DOIUrl":"https://doi.org/10.6028/JRES.011.054","url":null,"abstract":"No accurate description of the red and infrared portion of the arc spectrum of silicon has been published in the 40 years that have elapsed since Rowland's work which terminated at 5,948 A. In this paper, wave lengths are given for 130 new lines between 6,125 and 11,290 A, many of which are present in the solar spectrum, including the strongest hitherto unidentified Fraunhofer line. More than 50 percent of these lines have been classified as combinations between new terms and terms already established for Si I. The new terms arise from the electron configurations containing the 4p, 4/, and 5/ electrons.","PeriodicalId":56324,"journal":{"name":"Bureau of Standards Journal of Research","volume":"12 1","pages":"775"},"PeriodicalIF":0.0,"publicationDate":"1933-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"71341600","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 quantitative method for the evaluation of the color of manila-rope fiber was developed at the request of the Cordage Institute and the Cordage Committee of the Federal Specifications Board. Spectral reflection and colorimetric measure- ments showed that the variations in color correspond chiefly to variations in luminous reflectance. The reflectance at wave length 500 nut, which is obtainable with relatively simple apparatus, was found to be sufficient for the grading of the fiber for color. The fibers in a cross section of the rope are cut into lengths of 1.5 to 2.5 mm, mixed, extracted with petroleum ether, and spread out to give a smooth surface. The ratio of the reflectance of this surface to that of the usual white standard magnesium oxide surface for light of wave length 500 mjt (when the two surfaces are in effect equally illuminated at an angle of approximately 45° and viewed in a line approximately perpendicular to the surfaces) multiplied by 100 gives the numerical value, "Becker value", for the rope. The Becker value of the commercial ropes tested varied from 29.0 to 51.0. Before removal of the lubricant the values were from 8 to 16 units lower. The value obtained for a single specimen taken from a coil of rope was found to be within two units of the average value for several specimens. The method is prescribed in the latest revision of the Federal specification for manila rope.
{"title":"Evaluation of manila-rope fiber for color","authors":"G. Becker, W. Appel","doi":"10.6028/JRES.011.057","DOIUrl":"https://doi.org/10.6028/JRES.011.057","url":null,"abstract":"A quantitative method for the evaluation of the color of manila-rope fiber was developed at the request of the Cordage Institute and the Cordage Committee of the Federal Specifications Board. Spectral reflection and colorimetric measure- ments showed that the variations in color correspond chiefly to variations in luminous reflectance. The reflectance at wave length 500 nut, which is obtainable with relatively simple apparatus, was found to be sufficient for the grading of the fiber for color. The fibers in a cross section of the rope are cut into lengths of 1.5 to 2.5 mm, mixed, extracted with petroleum ether, and spread out to give a smooth surface. The ratio of the reflectance of this surface to that of the usual white standard magnesium oxide surface for light of wave length 500 mjt (when the two surfaces are in effect equally illuminated at an angle of approximately 45° and viewed in a line approximately perpendicular to the surfaces) multiplied by 100 gives the numerical value, \"Becker value\", for the rope. The Becker value of the commercial ropes tested varied from 29.0 to 51.0. Before removal of the lubricant the values were from 8 to 16 units lower. The value obtained for a single specimen taken from a coil of rope was found to be within two units of the average value for several specimens. The method is prescribed in the latest revision of the Federal specification for manila rope.","PeriodicalId":56324,"journal":{"name":"Bureau of Standards Journal of Research","volume":"11 1","pages":"811"},"PeriodicalIF":0.0,"publicationDate":"1933-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"71342168","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 sample of ethane of known purity was analyzed by the usual slow-combustion method; that is, over a hot platinum spiral in the presence of excess oxygen. The contraction after burning, the carbon dioxide produced, and the oxygen consumed were measured. The average results obtained from a series of 18 determinations indicated the impossibility of attaining the accuracies usually reported in the literature. The average volumetric equation for the reaction was C 2H 6 -|-3.5116 2 «= 1.9940 COii+ 2.5190 contraction. The weighted average eauation was CoH 6+ 3.513 2 «= 1.994 CO2+ 2.520 contraction. The contraction and oxygen consumed were invariably too high, and the carbon dioxide produced was invariably too low. The ethane was calculated from contraction, carbon dioxide, and oxygen separately and in various combinations, both uncorrected and corrected for deviations from theoretical molecular volumes. The average results from different methods of calculation varied from 99.13 percent to 100.76 percent. The best average value found by use of a single formula was 100.11 percent, and resulted from combining the contraction and carbon dioxide as one factor of an equation of which the other factor was oxygen. Such an equation eliminates part of the uncertainty concerning the proper method of correcting for deviation from theoretical molecular volumes. The averages of two pairs of formulas gave results very close to 100 percent. The ethane was also calculated on the assumption that methane, or propane, (known to be absent) was present. (The usual analysis would have been reported as methane and ethane.) Hydrocarbons other than ethane indicated by various methods of calculation from the average of the observed results varied from 0.3 percent of propane to 9.4 percent of methane. A number of sources of error are discussed. These include small measured losses of ethane and carbon dioxide in the distributor, and a small loss of carbon dioxide by solution in the water produced by the combustion and otherwise present. Such errors must be present in every apparatus of this type, and will effect the analysis of all hydrocarbons to some extent. The observed results may be explained by correcting for these errors, and for the known deviation of carbon dioxide from its theoretical molecular volume with a similar correction for ethane, which is somewhat higher than the best estimated value available.
{"title":"Critical study of the determination of ethane by combustion over platinum in the presence excess oxygen","authors":"M. Shepherd, J. R. Branham","doi":"10.6028/JRES.011.055","DOIUrl":"https://doi.org/10.6028/JRES.011.055","url":null,"abstract":"A sample of ethane of known purity was analyzed by the usual slow-combustion method; that is, over a hot platinum spiral in the presence of excess oxygen. The contraction after burning, the carbon dioxide produced, and the oxygen consumed were measured. The average results obtained from a series of 18 determinations indicated the impossibility of attaining the accuracies usually reported in the literature. The average volumetric equation for the reaction was C 2H 6 -|-3.5116 2 «= 1.9940 COii+ 2.5190 contraction. The weighted average eauation was CoH 6+ 3.513 2 «= 1.994 CO2+ 2.520 contraction. The contraction and oxygen consumed were invariably too high, and the carbon dioxide produced was invariably too low. The ethane was calculated from contraction, carbon dioxide, and oxygen separately and in various combinations, both uncorrected and corrected for deviations from theoretical molecular volumes. The average results from different methods of calculation varied from 99.13 percent to 100.76 percent. The best average value found by use of a single formula was 100.11 percent, and resulted from combining the contraction and carbon dioxide as one factor of an equation of which the other factor was oxygen. Such an equation eliminates part of the uncertainty concerning the proper method of correcting for deviation from theoretical molecular volumes. The averages of two pairs of formulas gave results very close to 100 percent. The ethane was also calculated on the assumption that methane, or propane, (known to be absent) was present. (The usual analysis would have been reported as methane and ethane.) Hydrocarbons other than ethane indicated by various methods of calculation from the average of the observed results varied from 0.3 percent of propane to 9.4 percent of methane. A number of sources of error are discussed. These include small measured losses of ethane and carbon dioxide in the distributor, and a small loss of carbon dioxide by solution in the water produced by the combustion and otherwise present. Such errors must be present in every apparatus of this type, and will effect the analysis of all hydrocarbons to some extent. The observed results may be explained by correcting for these errors, and for the known deviation of carbon dioxide from its theoretical molecular volume with a similar correction for ethane, which is somewhat higher than the best estimated value available.","PeriodicalId":56324,"journal":{"name":"Bureau of Standards Journal of Research","volume":"11 1","pages":"783"},"PeriodicalIF":0.0,"publicationDate":"1933-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"71341612","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":"Effect of heat treatment on the expansivity of a pyrex glass","authors":"J. B. Saunders, A. Q. Tool","doi":"10.6028/JRES.011.056","DOIUrl":"https://doi.org/10.6028/JRES.011.056","url":null,"abstract":"","PeriodicalId":56324,"journal":{"name":"Bureau of Standards Journal of Research","volume":"71 Pt B 1","pages":"799"},"PeriodicalIF":0.0,"publicationDate":"1933-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"71341652","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":"The isolation of mesitylene, pseudocumene, and hemimellitene from an Oklahoma petroleum","authors":"B. Mair, S. Schicktanz","doi":"10.6028/JRES.011.044","DOIUrl":"https://doi.org/10.6028/JRES.011.044","url":null,"abstract":"","PeriodicalId":56324,"journal":{"name":"Bureau of Standards Journal of Research","volume":"11 1","pages":"665"},"PeriodicalIF":0.0,"publicationDate":"1933-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"71341915","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":"Infrared absorption spectra of some plant pigments","authors":"R. Stair, W. Coblentz","doi":"10.6028/JRES.011.047","DOIUrl":"https://doi.org/10.6028/JRES.011.047","url":null,"abstract":"","PeriodicalId":56324,"journal":{"name":"Bureau of Standards Journal of Research","volume":"11 1","pages":"703"},"PeriodicalIF":0.0,"publicationDate":"1933-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"71341536","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":"The attraction between coils in the Rayleigh current balance","authors":"C. Snow","doi":"10.6028/JRES.011.045","DOIUrl":"https://doi.org/10.6028/JRES.011.045","url":null,"abstract":"","PeriodicalId":56324,"journal":{"name":"Bureau of Standards Journal of Research","volume":"11 1","pages":"681"},"PeriodicalIF":0.0,"publicationDate":"1933-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"71341929","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":"Formula for specific volumes of saturated vapors","authors":"C. H. Meyers","doi":"10.6028/JRES.011.046","DOIUrl":"https://doi.org/10.6028/JRES.011.046","url":null,"abstract":"","PeriodicalId":56324,"journal":{"name":"Bureau of Standards Journal of Research","volume":"11 1","pages":"691"},"PeriodicalIF":0.0,"publicationDate":"1933-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"71341528","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":"Phase equilibria in the systems TiO2, TiO2-SiO2 and TiO2-Al2O3","authors":"E. N. Bunting","doi":"10.6028/JRES.011.049","DOIUrl":"https://doi.org/10.6028/JRES.011.049","url":null,"abstract":"","PeriodicalId":56324,"journal":{"name":"Bureau of Standards Journal of Research","volume":"11 1","pages":"719"},"PeriodicalIF":0.0,"publicationDate":"1933-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"71341555","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":"Preparation of calcium lactobionate and lactobionic delta-lactone","authors":"H. Isbell","doi":"10.6028/JRES.011.048","DOIUrl":"https://doi.org/10.6028/JRES.011.048","url":null,"abstract":"","PeriodicalId":56324,"journal":{"name":"Bureau of Standards Journal of Research","volume":"11 1","pages":"713"},"PeriodicalIF":0.0,"publicationDate":"1933-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"71341547","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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