Laboratory scale measurements have been made of the ability of certain alkaline salts, commonly used as laundry soap builders, to hold carbon particles in suspension, and thus prevent their deposition on fabric during the washing process. In the absence of soap little difference was noted between any of the builders studied, the suspending power being, on the whole, poorer than that of distilled water. In general, the addition of builders to soap solutions resulted in a decrease in the suspending power of the soap, this effect increasing with increasing builder concentration. The builders fall into three general classifications, viz.: simple electrolytes, silicates, and phosphates. Within each of these groups of builders the suspending power of a built soap solution increases with decreasing pH of the solution. A tentative explanation of the influence of added builders on the suspending power of soap solutions is offered, on the basis of interference with the normal adsorption of soap by the carbon partic...
{"title":"THE SUSPENDING POWER OF DETERGENT SOLUTIONS: II. SOAP-BUILDER SOLUTIONS","authors":"A. Weatherburn, G. Rose, C. H. Bayley","doi":"10.1139/CJR50F-033","DOIUrl":"https://doi.org/10.1139/CJR50F-033","url":null,"abstract":"Laboratory scale measurements have been made of the ability of certain alkaline salts, commonly used as laundry soap builders, to hold carbon particles in suspension, and thus prevent their deposition on fabric during the washing process. In the absence of soap little difference was noted between any of the builders studied, the suspending power being, on the whole, poorer than that of distilled water. In general, the addition of builders to soap solutions resulted in a decrease in the suspending power of the soap, this effect increasing with increasing builder concentration. The builders fall into three general classifications, viz.: simple electrolytes, silicates, and phosphates. Within each of these groups of builders the suspending power of a built soap solution increases with decreasing pH of the solution. A tentative explanation of the influence of added builders on the suspending power of soap solutions is offered, on the basis of interference with the normal adsorption of soap by the carbon partic...","PeriodicalId":9392,"journal":{"name":"Canadian journal of research","volume":"272 1","pages":"363-375"},"PeriodicalIF":0.0,"publicationDate":"1950-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"90082654","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 carbon dioxide production of deer mice at 1° to 18 °C. was not affected by humidity, but increasing the temperature decreased the carbon dioxide production of the mice. Heat transmission of mouse fur was also independent of humidity.
{"title":"THE EFFECT OF HUMIDITY AND TEMPERATURE ON CARBON DIOXIDE PRODUCTION OF DEER MICE AND ON HEAT TRANSMISSION THROUGH THEIR FUR","authors":"J. Hart","doi":"10.1139/CJR50D-018","DOIUrl":"https://doi.org/10.1139/CJR50D-018","url":null,"abstract":"The carbon dioxide production of deer mice at 1° to 18 °C. was not affected by humidity, but increasing the temperature decreased the carbon dioxide production of the mice. Heat transmission of mouse fur was also independent of humidity.","PeriodicalId":9392,"journal":{"name":"Canadian journal of research","volume":"93 1","pages":"280-284"},"PeriodicalIF":0.0,"publicationDate":"1950-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"77666231","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}
Undercooling points are shown to be unreliable as a measure of insect cold-hardiness. Insects held in an undercooled state freeze at irregular intervals, often over long periods of time. Freezing, which is fatal to most insects, is initiated by the formation of an ice-crystal nucleus, and the probability of such formation is dependent upon the extent of undercooling (temperature), cold-hardiness (a complex resulting from previous treatment), and time. For a specified degree of cold-hardiness, the probability of freezing is dependent upon temperature and time. If the temperature is fixed, the probability of freezing can be expressed in units of time. Freezing can take place on a rising temperature gradient as well as on a falling one.Unless an overwintering population is adequately protected by its environment and a high degree of cold-hardiness, losses from freezing will take place by degrees during the entire winter.
{"title":"Time as a Factor in the Freezing of undercooled Insects.","authors":"R. Salt","doi":"10.1139/CJR50D-019","DOIUrl":"https://doi.org/10.1139/CJR50D-019","url":null,"abstract":"Undercooling points are shown to be unreliable as a measure of insect cold-hardiness. Insects held in an undercooled state freeze at irregular intervals, often over long periods of time. Freezing, which is fatal to most insects, is initiated by the formation of an ice-crystal nucleus, and the probability of such formation is dependent upon the extent of undercooling (temperature), cold-hardiness (a complex resulting from previous treatment), and time. For a specified degree of cold-hardiness, the probability of freezing is dependent upon temperature and time. If the temperature is fixed, the probability of freezing can be expressed in units of time. Freezing can take place on a rising temperature gradient as well as on a falling one.Unless an overwintering population is adequately protected by its environment and a high degree of cold-hardiness, losses from freezing will take place by degrees during the entire winter.","PeriodicalId":9392,"journal":{"name":"Canadian journal of research","volume":"23 1","pages":"285-291"},"PeriodicalIF":0.0,"publicationDate":"1950-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"78729355","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}
Intensive surveys of the physiological races of Cladosporium fulvum Cke. have been carried out during the past decade in southwestern Ontario, as a result of which seven such races have been identified. These are separated by differential reactions of the following hosts: Lycopersicon esculentum Mill. varieties Potentate, Stirling Castle, Vetomold, V-121, and V-473; L. pimpinellifolium (Jusl.) Mill., Vineland, No. 160 and No. 11-22-15 strains; L. hirsutum Humb. and Bonpl. and L. hirsutum var. glabratum Muller. Evidence is presented that only two of these races existed when the surveys began and that the other five have arisen, probably through mutation, during the period under study. There is further a strong suggestion that the stimulus responsible for these mutations is somehow related to the colonization of an incompatible host by a race which remains stable pathogenically while in association with a susceptible host. Comparable mutants have not been encountered under experimentally controlled conditio...
黄枝孢霉生理小种的深入调查。在过去的十年里，在安大略省西南部进行了一系列的研究，结果发现了七个这样的种族。它们通过以下寄主的不同反应分离:品种potate, Stirling Castle, Vetomold, V-121和V-473;小檗属植物轧机。Vineland, 160号和11-22-15号菌株;毛毛草。和Bonpl。和l.h hsutum var glabratum Muller。有证据表明，在调查开始时，这些种族中只有两个存在，其他五个可能是在研究期间通过突变而出现的。进一步有一种强烈的暗示，导致这些突变的刺激在某种程度上与一个种族对一个不相容的宿主的定殖有关，这个宿主在与一个易感宿主相关的同时保持了稳定的致病性。在实验控制的条件下还没有遇到类似的突变体。
{"title":"STUDIES IN RACIAL TRENDS AND CONSTANCY IN CLADOSPORIUM FULVUM COOKE","authors":"D. Bailey","doi":"10.1139/CJR50C-032","DOIUrl":"https://doi.org/10.1139/CJR50C-032","url":null,"abstract":"Intensive surveys of the physiological races of Cladosporium fulvum Cke. have been carried out during the past decade in southwestern Ontario, as a result of which seven such races have been identified. These are separated by differential reactions of the following hosts: Lycopersicon esculentum Mill. varieties Potentate, Stirling Castle, Vetomold, V-121, and V-473; L. pimpinellifolium (Jusl.) Mill., Vineland, No. 160 and No. 11-22-15 strains; L. hirsutum Humb. and Bonpl. and L. hirsutum var. glabratum Muller. Evidence is presented that only two of these races existed when the surveys began and that the other five have arisen, probably through mutation, during the period under study. There is further a strong suggestion that the stimulus responsible for these mutations is somehow related to the colonization of an incompatible host by a race which remains stable pathogenically while in association with a susceptible host. Comparable mutants have not been encountered under experimentally controlled conditio...","PeriodicalId":9392,"journal":{"name":"Canadian journal of research","volume":"49 1","pages":"535-565"},"PeriodicalIF":0.0,"publicationDate":"1950-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"85664404","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}
Monthly samples of cleaned weed seed screenings and of screenings oil (commercially solvent extracted) examined over a six-month period indicated that the composition of the screenings varied widely but that of the oil was remarkably constant. The composition of the weed seed was: wild mustard, mostly Brassica arvensts (53–79% av. 68%) mixed weed seeds (13–35%, av. 23%), crop seeds (4–10%, av. 6.6%), and broken and unidentified seeds (1–6% av 3%) The average characteristics of the oil were: iodine value, 124; saponification number, 182; free tatty acid (as oleic), 2%; relative light transmission (cf. mineral oil), 5% at 440 mμ, 18% at 540 mμ, 26% at 660 mμ. Appearance of the oil and response to processing were similar to those of rape and mustard seed oils. Small scale taste panel tests indicated that processed screenings oil was generally not as palatable as corn or cottonseed salad oils, but that screenings shortening was generally as acceptable as the control (commercial vegetable shortenings) the scre...
{"title":"CANADIAN ERUCIC ACID OILS: V. PHYSICAL, CHEMICAL, AND EDIBLE PROPERTIES OF OIL FROM WEED SEED SCREENINGS","authors":"X. H. Grace, H. Lips, A. Zuckerman","doi":"10.1139/CJR50F-036","DOIUrl":"https://doi.org/10.1139/CJR50F-036","url":null,"abstract":"Monthly samples of cleaned weed seed screenings and of screenings oil (commercially solvent extracted) examined over a six-month period indicated that the composition of the screenings varied widely but that of the oil was remarkably constant. The composition of the weed seed was: wild mustard, mostly Brassica arvensts (53–79% av. 68%) mixed weed seeds (13–35%, av. 23%), crop seeds (4–10%, av. 6.6%), and broken and unidentified seeds (1–6% av 3%) The average characteristics of the oil were: iodine value, 124; saponification number, 182; free tatty acid (as oleic), 2%; relative light transmission (cf. mineral oil), 5% at 440 mμ, 18% at 540 mμ, 26% at 660 mμ. Appearance of the oil and response to processing were similar to those of rape and mustard seed oils. Small scale taste panel tests indicated that processed screenings oil was generally not as palatable as corn or cottonseed salad oils, but that screenings shortening was generally as acceptable as the control (commercial vegetable shortenings) the scre...","PeriodicalId":9392,"journal":{"name":"Canadian journal of research","volume":"19 1","pages":"401-411"},"PeriodicalIF":0.0,"publicationDate":"1950-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"82258874","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 moose, Alces americana, in British Columbia reaches its greatest populations in the young second growth forest areas. Numbers decrease as the forest approaches its climax stage. The decline in population is known to be mainly the result of malnutrition.The present study of three stages in forest succession growing under virtually identical conditions of soil and climate has concerned itself with quantity of available palatable browse; carotene and ascorbic acid content of available palatable and unpalatable trees and shrubs; and with determination of values for moisture, protein, carbohydrate, ether extractives, and total mineral content. Most of the analyses are confined to the winter dormant period.It is determined that the forest changes studied involve a reduction in quantity of palatable browse to about one-third; that there is an increase of carotene values and possibly of total mineral content in the vegetation on more advanced forest areas, but that in ascorbic acid content, ether extractives,...
{"title":"The effect of forest succession upon the quantity and upon the nutritive values of woody plants used as food by moose.","authors":"I. M. Cowan, W. Hoar, J. Hatter","doi":"10.1139/CJR50D-016","DOIUrl":"https://doi.org/10.1139/CJR50D-016","url":null,"abstract":"The moose, Alces americana, in British Columbia reaches its greatest populations in the young second growth forest areas. Numbers decrease as the forest approaches its climax stage. The decline in population is known to be mainly the result of malnutrition.The present study of three stages in forest succession growing under virtually identical conditions of soil and climate has concerned itself with quantity of available palatable browse; carotene and ascorbic acid content of available palatable and unpalatable trees and shrubs; and with determination of values for moisture, protein, carbohydrate, ether extractives, and total mineral content. Most of the analyses are confined to the winter dormant period.It is determined that the forest changes studied involve a reduction in quantity of palatable browse to about one-third; that there is an increase of carotene values and possibly of total mineral content in the vegetation on more advanced forest areas, but that in ascorbic acid content, ether extractives,...","PeriodicalId":9392,"journal":{"name":"Canadian journal of research","volume":"1 1","pages":"249-271"},"PeriodicalIF":0.0,"publicationDate":"1950-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"89323445","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}
Fragmented spinach chloroplasts were stored for one year in 0.5 M sucrose at −40 °C. with almost negligible losses of photochemical activity. Thawed chloroplasts and freshly isolated chloroplasts showed similar rates of deterioration at 10 °C. Washed chloroplasts did not show as high retention of activity during low temperature storage as crude chloroplast suspensions. High retentions of activity were observed with chloroplasts from different plant species, as well as with different oxidants. The activities of subsamples that were frozen and thawed in a standard way agreed within 5%. Deterioration during lyophilization of chloroplasts occurred chiefly during the early stages of drying, and was lessened by sucrose. The stability of lyophilized chloroplasts in storage varied directly with the degree of desiccation and inversely with the storage temperature; little deterioration occurred in thoroughly dried chloroplasts during lengthy storage at or below 5 °C.
{"title":"STORAGE OF ISOLATED CHLOROPLASTS WITHOUT LOSS OF PHOTOCHEMICAL ACTIVITY","authors":"P. Gorham, K. A. Clendenning","doi":"10.1139/CJR50C-030","DOIUrl":"https://doi.org/10.1139/CJR50C-030","url":null,"abstract":"Fragmented spinach chloroplasts were stored for one year in 0.5 M sucrose at −40 °C. with almost negligible losses of photochemical activity. Thawed chloroplasts and freshly isolated chloroplasts showed similar rates of deterioration at 10 °C. Washed chloroplasts did not show as high retention of activity during low temperature storage as crude chloroplast suspensions. High retentions of activity were observed with chloroplasts from different plant species, as well as with different oxidants. The activities of subsamples that were frozen and thawed in a standard way agreed within 5%. Deterioration during lyophilization of chloroplasts occurred chiefly during the early stages of drying, and was lessened by sucrose. The stability of lyophilized chloroplasts in storage varied directly with the degree of desiccation and inversely with the storage temperature; little deterioration occurred in thoroughly dried chloroplasts during lengthy storage at or below 5 °C.","PeriodicalId":9392,"journal":{"name":"Canadian journal of research","volume":"14 1","pages":"513-524"},"PeriodicalIF":0.0,"publicationDate":"1950-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"75308344","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":"Note on the Stereoisomers of 2,3-Butanediol Produced by Yeast","authors":"A. Neish","doi":"10.1139/CJR50B-079","DOIUrl":"https://doi.org/10.1139/CJR50B-079","url":null,"abstract":"","PeriodicalId":9392,"journal":{"name":"Canadian journal of research","volume":"68 1","pages":"660-661"},"PeriodicalIF":0.0,"publicationDate":"1950-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"88062018","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}
New polyesters with basic units containing 6, 7, 8, 9, 10, 13, and 14 chain atoms have been prepared from levo-2,3-butanediol and ethyl oxalate, ethyl malonate, dimethyl terephthalate, maleic anhydride, succinic, glutaric, adipic, azelaic, and sebacic acids, and from meso-2,3-butanediol and o-phthalic anhydride. Esterification of 2,3-butanediol with a dibasic acid, or its anhydride, is accompanied by a side reaction, in which butanone-2 and the cyclic methyl ethyl ketal are formed. The purified polyesters, with the exception of the poly-malonate, appear to be composed of regularly recurring acid and diol segments over the molecular weight ranges investigated. Without exception they are amorphous resins or balsams. Polyesters formed from saturated aliphatic dibasic acids become progressively softer as the number of methylene groups in the acid segment increases. The polymeric oxalate, on distillation in vacuo, is converted to a macrocrystalline cyclic monomer.
{"title":"PRODUCTION AND PROPERTIES OF 2,3-BUTANEDIOL XXXVI. LINEAR POLYESTERS OF 2,3-BUTANEDIOL","authors":"R. Watson, N. Grace, J. Barnwell","doi":"10.1139/CJR50B-078","DOIUrl":"https://doi.org/10.1139/CJR50B-078","url":null,"abstract":"New polyesters with basic units containing 6, 7, 8, 9, 10, 13, and 14 chain atoms have been prepared from levo-2,3-butanediol and ethyl oxalate, ethyl malonate, dimethyl terephthalate, maleic anhydride, succinic, glutaric, adipic, azelaic, and sebacic acids, and from meso-2,3-butanediol and o-phthalic anhydride. Esterification of 2,3-butanediol with a dibasic acid, or its anhydride, is accompanied by a side reaction, in which butanone-2 and the cyclic methyl ethyl ketal are formed. The purified polyesters, with the exception of the poly-malonate, appear to be composed of regularly recurring acid and diol segments over the molecular weight ranges investigated. Without exception they are amorphous resins or balsams. Polyesters formed from saturated aliphatic dibasic acids become progressively softer as the number of methylene groups in the acid segment increases. The polymeric oxalate, on distillation in vacuo, is converted to a macrocrystalline cyclic monomer.","PeriodicalId":9392,"journal":{"name":"Canadian journal of research","volume":"25 1","pages":"652-659"},"PeriodicalIF":0.0,"publicationDate":"1950-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"81621638","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 fibrous holocellulose was isolated from white birch using hot acidified sodium chlorite solutions. Pulps of varying hemicellulose content were prepared by alkaline treatment, and their beating and sheetmaking properties compared with the original holocellulose. Tensile strength increased with hemicellulose content, whereas tearing resistance and fold endurance decreased. Bursting strength reached a maximum at about 15% alkali-extractable hemicellulose content. Pulps obtained in yields of 46–53%, i.e., containing 10–20% hemicellulose, possessed the best over-all strength.A bleached sulphite pulp prepared from the same chips in a yield of 43.6% contained 20.7% alkali-extractable hemicellulose. The over-all yield of α-cellulose was about 6% lower, based on the wood, than in the case of the holocellulose, thus indicating greater fiber damage during the sulphite process. Hand sheets made from the sulphite pulp were inferior to sheets made from a chlorite pulp of the same hemicellulose content in bursting and...
{"title":"THE EFFECT OF HEMICELLULOSES ON THE PAPERMAKING PROPERTIES OF WHITE BIRCH","authors":"D. A. Sitch, H. B. Marshall","doi":"10.1139/CJR50F-034","DOIUrl":"https://doi.org/10.1139/CJR50F-034","url":null,"abstract":"A fibrous holocellulose was isolated from white birch using hot acidified sodium chlorite solutions. Pulps of varying hemicellulose content were prepared by alkaline treatment, and their beating and sheetmaking properties compared with the original holocellulose. Tensile strength increased with hemicellulose content, whereas tearing resistance and fold endurance decreased. Bursting strength reached a maximum at about 15% alkali-extractable hemicellulose content. Pulps obtained in yields of 46–53%, i.e., containing 10–20% hemicellulose, possessed the best over-all strength.A bleached sulphite pulp prepared from the same chips in a yield of 43.6% contained 20.7% alkali-extractable hemicellulose. The over-all yield of α-cellulose was about 6% lower, based on the wood, than in the case of the holocellulose, thus indicating greater fiber damage during the sulphite process. Hand sheets made from the sulphite pulp were inferior to sheets made from a chlorite pulp of the same hemicellulose content in bursting and...","PeriodicalId":9392,"journal":{"name":"Canadian journal of research","volume":"29 1","pages":"376-389"},"PeriodicalIF":0.0,"publicationDate":"1950-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"79251499","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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