Document 7Ojaaappn6vXEQ5JB9mXQyzgB

December, 1925 INDUSTRIAL AND ENGINEERING CHEMISTRY 1255 lered nake due asily ts in lyees 1 the it is days e, or srity, In our own works, therefore, we have felt it better to use, instead, the total hours worked per accident; and if we say that in a certain department there has been one accident per month for every 21,600 hours worked, or, since the full time man averages 206 working hours per month, that one man 'out of approximately every one hundred gets hurt each month, it is something they can grasp. Similarly, we use the average actual hours lost per accident as a meas ure of accident severity, and it is quite evident the workers will the more readily understand when we say the fellows hurt last year were "knocked out" for 72 hours each or an average of a week and a half, than they will if we tell them their severity rate is 0.27 as compared with 0.29 last year. How Fatal Accidents and Permanent Disability are. . Reckoned If in your plant you had among the accidents one fatality, how would you take it into account in estimating the severity? | Or, if an accident resulted in permanent total ot permanent partial disability, how Would it be included? A careful study of these matters by the International Association of Industrial Accident Boards and Commissions has led them to establish a scale of time losses or disability ratings varying with the degree of disability, death, or permanent disability, representing a time loss of 6000 days. Accordingly; if in figuring your accident severity rate for any given period you had twenty nonfatal accidents with a total loss in time of 100 days and, in addition, one fatal accident, you would have to consider your accidents as 21 with a total loss of 6100 days. Similarly, if an accident resulted in permanent total disability, the amount of the loss would be the same. Sjtill further, if an accident produced permanent partial disability, as the dismemberment of an arm above the elbow, or::the permanent' disability of any one finger, the losses would be 4500ter 300 days, respectively. ional ions. Effect of Yellow and Brown Iron Oxide Pigments rally, ther, upon Rate of Oxidation of Linseed Oil1 tings By F. H. Rhodes and J. D. Cooper, Jr. Co r n s u , Un iv e r s it y , It h a c a , N. Y. IOW diet aery the e of lent e to i ob3 not y of lords HE effect of certain of Ochers tend first to retard and then to accelerate the T the red iron oxide pig ments upon the rate drying of the oil. The initial retardation is caused by the adsorption of the drier from the oil, the final ac of oxidation of linseed oicleleration is due to the formation of iron soaps which has been studied by Rhodes, act as catalysts. The iron oxide in an ocher reacts Burr, and Webster.2 The in less readily with the drying oil than does the ferric vestigation described in the oxide in a red iron oxide pigment. Siennas and umbers present article was under show less effect on the initial rate of oxidation of the taken for the purpose of ob oil than does ocher because the removal of the lead drier taining corresponding data in is compensated by the formation of a small amount of regard to the effects of the manganese drier. Materials The linseed oil used in this work was pure refined linseed oil from North American seed. It showed the follow ing analysis: Specific fravity at 25.5 C. 0.939 Refractive index at 25 C. 1.4788 Add cumber 0.452? Saponification number 195.3 Iodine number 170.5. ochers, siennas, umbers, and metallic browns. The analyses of the pigments used are shown by Table I. Procedure The apparatus used and the procedure followed in deter mining the rate of oxidation of the oil were similar to those described by Rhodes and Van Wirt.s Two parts by weight of .the..pigment.to he...studied.were, mixed..with..three parts ol the vehicle and the mixture was ground to a smooth paint. Ijhe vehicle used in each case consisted of raw linseed oil in which had been dissolved sufficient lead linoleate drier to contain an amount of lead equivalent to 0.2 per cent by weight of the oil. Each paint was allowed to age in a sealed con tainer for at least 2 weeks before being tested. Weighted samples of the paint were then exposed to an atmosphere of pure oxygen at 30 C., and the rate of absorption of oxygen and the rate of evolution of volatile matter were measured. The rate of oxidation of the vehicle alone was determined in a similar manner. In each case at least two parallel determina tions were made with each paint. The individual determina tions gave results which agree with each other within the limits of experimental error. 1 Received June 16, 1925. * Th is Jo u r n a l , 16, 960 (1924). 15, 1135 (1923). Table I--Analyses of Pigments Com Pig me n t bined Free SiOa -Fe*0t AlaOj CaO MnO CO* H*0 HtO White ocher 61.86 4.72 24.50 -- 9.00 8,72 0.05 French ocher 5377 18.86 17.95 0.10 : 9.54 0:23 Domestic ocher 46772 22.79 18.79 -- 0,02 `10168 0.47 Raw sienna 43.98 34.22 12.30 0.69 0.60 0.44 6.68 1.01 Burnt Italian sienna 19.40 69.90 -8.65 -------- 0.50- 0;08- - OiOO 1,54 Burnt American umber 20.14 54.14 9.41 1.27 4.72 0.34 8.21 1787 Burnt Turkey umber 17.58 62.04 12.36 ~~ 10.63 0.03 6.76 0762 Metallic brown 14.15 75.50 6.10 -- 0.03 1.83 0766 Metallic brown 30.23 51.33 7.89 1.32 0.30 7.81 1.10 Results The results are shown graphically by the accompanying curves, in which the amounts of oxygen absorbed and the amounts of volatile matter evolved (each expressed in terms of percentage by weight of the oil in the paint) are plotted against the lengths of time of exposure. For each pigment there is plotted only one curve, depicting the average results of two or more cheek determinations. On each diagram the graphs for the rate of absorption of oxygen and-the rate of evolution of volatile matter for the vehicle alone are -shown for purposes of comparison. . ;' Oc h er s (Figure 1)--Each of the ochers tested shows:a marked effect in retarding the initial rate of oxidation of 4256 INDUSTRIAL AND ENGINEERING-CHEMISTRY Vol. 17, No. 12 tbe oil'.i' This'iAi'tliafbref&rdation is probably caused by the Jadsorptiou of some Of the'lead drier by the pigment. The Very fiaely' divided' Frehfch ocher shows a much more: pro nounced' effect'in 'delaying the oxidation than does the some.what'Coarser domestib'dcher. In order to determine whether ob not these pigments do actually adsorb the drier from the vehicle,- paints made from French ocher and from domestic Ocher were centrifuged to separate the pigment, and the authorities explain the difference of color between the ochers and the reds by assuming that the ochers contain yellow ferric hydroxide whereas in the red pigments the iron is present aB red ferric oxide. If this were true the red pigments would be less reactive than the ochers and would show less effect upon the rate of drying of the oil. The writers are inclined to ascribe the difference between the two types of pigments to the fact that the ferric oxide is strongly adsorbed in (or on) December s E The cen gave a dis failure of i Pr< clear supernatant vehicle was analyzed for lead. A sample of the vehicle alone was also;centrifuged to remove any sus pended matter,and the clarified oil was analyzed for lead. The results were as follows: PlOUgNT None French ocher Domestic ocher Concentration of lead in centrifuged liquid Per cent 0.094 Trace 0.019 These experiments prove that the pigments do actually remove lead drier by adsorption, and that the adsorption is more pronounced in the. case of the French ocher. It does hot follow, of course, that in a paint made with French ocher the lead drier is absolutely inert, since it is possible that lead linoleate adsorbed on the pigment particles may still catalyze the oxidation of the oil to some extent. It is reasonable to assume, however, that the adsorbed drier will be somewhat less effective than drier actually in solution in the oil. . Both the French ocher and the domestic ocher tend to increase the final rate of oxidation of the oil, so that the paints made from these pigments ultimately absorb more oxygen than does the vehicle without pigment. This effect of the ochers in increasing Hie final rate of oxidation is pre sumably due to the interaction of the iron oxide with the acidic substances produced during the drying of the oil, with the resulting formation of iron driers which act as catalysts in promoting the oxidation of linseed oil.. The white ocher, which is really a clay-containing very little iron oxide, does the particles of clay and therefore combines less readily with the acidic oxidation products of the oil. Sie n n a s (Figure 2)--In its effect upon the oxidation of linseed oil raw sienna behaves somewhat like domestic ocher. Burnt sienna, however, shows very little effect in decreasing the initial rate of oxidation of the oil. Experiments made to determine the extent to which lead drier is removed from linseed oil by adsorption on sienna pigments gave the following results: Pig me n t s None Raw sienna Burnt sienna Concentration of lead in centrifuged liquid Per cent 0.094 Trace 0.0049 The burnt sienna does not retard the initial rate of oxidation nearly so much as does domestic ocher, although the sienna adsorbs the lead drier more strongly than does the ocher, and raw sienna has less effect upon the rate of oxidation than has French ocher, although both pigments adsorb the drier almost completely. Apparently, the formation of small amounts of manganese drier from the manganese in the sienna tends largely to counteract the effect of the removal of the lead drier. That such manganese driers are formed is shown by the fact that the centrifuged vehicle from the sienna paints gives a distinct, although faint, test for manganese. Umber s (Figure 3)---Neither burnt Turkey umber nor burnt American umber retards the initial rate of oxidation of the oil; in fact, both paints made with umber dried more rapidly than did the vehicle alone. This agrees with the the oil. The. ochers, however, accelerate the final drying of the Oil to a lesser extent than do some of the iron oxide reds-- a,`for"extanjile,-'bright oiade and:Tuscan red;*- Many observation of Ingalls4 that umber markedly increases the rate of drying of linseed oil. Experiments made to determine the extent to which umber adsorbs the lead drier gave the following results: * Clum. Met. Eng., 22, 690 (1920). he T ara 0U frequentlj the liter gives the followed of the si gAibvdeerrehvailec dealing w together 1 erences. that beet gum, whi mg9 prep hours in i tains froi arabinose The pi l with the s gum, has : when pre Note-- 1 and other s J l Arizona, an i in irregulai weighing 5 When the { . down the l i Rece Divisions < the 70th h August 3 t l This the plant g 1 western pa ' * Sche ' 360, 289 (1 ' and Schuh (1886); J. . Ruff and J ; ind., 46, 2 Z, angew, . * Schulze, i (1897); 31 and Blau, % . Sac* (Lond ' Houers an * Han t "Ch Bioc ' 7 Han ; Tm< C. A / / & December, 1925 INDUSTRIAL AND ENGINEERING CHEMISTRY 1257 Pig me n t s None Burnt American umber Concentration of lead in centrifuged liquid Percent 0.094 Faint trace The centrifuged vehicle from the paint made with umber gave a distinct test for manganese. It is obvioua.that the failure of umber to retard the initial rate of oxidation of the oil is due to the formation of a small amount, of manganese drier by the interaction of the oil and the. pigment. Me t a l l ic Br o w n (Figure 4)--Paints made from metallic brown as a pigment behave very much like paints made from domestic ocher, although both the decrease in the initial rate of oxidation and the increase in the final rate of oxidation are somewhat less pronounced. Preparation of Z-Arabinose from Mesquite Gum1' * * 4 By Ernest Anderson and Lila Sands Un iv e r s it y or Ar iz o n a, Tu c s o n , Ar iz . HE preparation of I- T arabinose from vari ous plant products has Arabinose is readily prepared by the hydrolysis of mesquite gum for 3 hours at 80 C. in six times its weight of 4 per cent sulfuric acid. After removal of the that it can be powdered in a mortar. This gum is collected by the lndians and Mexicans. It is carried by most of the drug stores of Tucson and frequently-been described inacid as barium sulfate the neutral solution is con with a few weeks* notice could be fch the .literature.! .Browne.?: centrated, ^ the- salts precipitated by alcohol, and the supplied in large amounts by the of gives the general - method' ..i alcohol sohi.tiooof the sugars concentrated and allowed followed in the preparation to crystallize. The yield of crystalline sugar varies Martin Drug Co., of Tucson, at 30 cents or less-per pound. Un doubtedly other chemical supply 3r. i of the sugar. Iippmann,5 * from 27 to 36 per cent of the gum used and the melting * hou&s of the Southwest, such as the Qg to >m Abderhalden and Beilstem,7 give reviews of the literature dealing with the preparation, point varies from 140 to 155? C. Thlsproductcan.be recrystallized from water, mixtures of water and al-. cohol, and from glacial acetic acid. Mesquite gum can . Mipe &; Smelter Supply Co.s pf El Paso, coidd seciii-e large amounts of the' gum. Mesquite gum is fully described in an article by Anderson, Qg together with numerous ref be purchased in large amounts in the Southwest. Sands, and Sturgis. Am. J. Pharm erences. Hudson, states acy, 97, 589 (1925). that beet pulp is a better source of arabinose than cherry Dissolve 500 grams of mesquite gum in 3 liters of water ) gum, which is usually recommended by textbooks. Hard contained in a 5-liter flask. (If the mixture of mesquite gum ing9 prepares arabinose by hydrolyzing beet pulp for 1.5 and water is let stand for 10 hours and then shaken.it will hours in a boiling 1 per cent solution of Bulfuric acid and ob form a clear solution. The same result can be attained by tains from 4 to 5 per cent of the beet pulp in the form of heating the mixture in the boiling water bath for an hour >n arabinose. with frequent stirring. The acid should not be added until la The present investigation was undertaken in connection the gum is dissolved.) To this solution add a cool solution with the study of plant gums. The crude material, mesquite of 125 grams of concentrated sulfuric acid in 70 cc. of water, >n gum, has been found to give good yields of the J-arabinose and heat to 80 C. for 3 hours in a large water bath. Pre le when prepared by the following method. cipitate the sulfuric acid by adding to the hot solution, a of hot concentrated solution of 410 grams crystalline barium 16 Note--Mesquite gum is found on the mesquite tree, Prosopis julifioro, hydroxide. (The barium hydroxide should not contain more a! is 1a and other species of mesquite, through a great part of Texas, New Mexico, -Arizona, and northern Mexico. The gumexudes from the stem and branches irregular, roundish, or vermiform pieces of various sizes, usually small, weighing 6 grams or less, but sometimes weighing as much as 25 grams. than traces of carbonate or the solution will foam.) Ad just the solution to neutrality by adding, small amounts of barium hydroxide solution or sulfuric acid solution as re When the gum first appears it is soft and sticky. At this stage it often runs quired. Let the barium sulfate settle, siphon the dear solu >r [down the branch. It gradually dries out and becomes hard and so brittle tion, filter the barium sulfate on a Bilchner funnd, and wash it with hot water. Combine the solutions and concentrate :e 1 Received June 24, 1925. Presented before the joint meeting of the in an evaporating dish on the boiling water bath,-to a volume ie Divisions of Organic Chemistry and Chemistry of Medicinal Products at of approximately 650 cc. When the gum is hydrolyzed at the 70th Meeting of the American Chemical Society, Eos Angeles, Calif., August 3 to 8, 1925. 80 C. the water cannot be distilled off in vacuo because of * This is the first of a series of papers dealing with the chemistry of foaming but must be evaporated in an open dish. Transfer ithe plant gums in general and especially with those that occur in the south western part of the United States. * Scheibler, Ber., 1, 58 (1869); 6, 612 (1873); Allen and Tollens, Ann., $160, 289 (1890); Ullick, Z. Zuckerind. u. Landw., 28, 274 (1894); Marquardt end Schulz, Z. Ver. deui. Zuckerind., 51, 864 (1901); Bauer, Ibid., 56, 751 the solution to a 3-liter flask. The total volume should be 700 cc. To this solution add with shaking" 1.5 liters of '95 per cent ethyl alcohol. Let stand until the solution is no longer turbid. Decant the sugar solution from the gummy (1886); J. prakt. Chem80, 367 (1884); Kiliani, Ber., 19, 3029 (1886); Ruff and Meusser, Ibid., 84, 1364 (1901); Subaschow, Z. Ver. dent. Zucker ind., 46, 270 (1896); Tollens and Browne, Ber., 85, 1464 (1902); Tollens, Z. angew. Chem., 20, 477 (1902); Steiger and Schulze, Ber., 28, 3110 (1890); Schulze, Z. physiol. Chem., 16, 386 (1892); Wroblewski, Ber., SO, 2289 barium salts and extract the latter four times under, the reflux, each time with 500 cc. of boiling methanol (prepared by distilling wood alcohol over quicklime). After the third extraction transfer the salt to an evaporating dish and (1867); 81, 1128 (1898); Yoshimura, Chem. Zentr., 1896, 46; Winterstein ;ond Blau, Z. physiol. Chem., 75, 410 (1911); Power and Salway, J. Chem. >$oc. (London), 108, 191 (1913); Kiliani and Koehler, Ber., 87, 1210 (1904); rHouers and Tollens, Ibid., 86/ 3306 (1903). . 4 .Handbook of Sugar Analysis, 1912, p, 548. grind to a powder. Concentrate the ethyl alcohol' solution of the sugars in vacuo on the boiling water bath to a thin sirup. (If all the water is removed by heating , the gum in vd&Uo for some time the sugar will not crystallize. Seeding with '* "Chemie derZuckerarten/' Vol. I, 3rd ed., 1904, p. 55. * Biochemische Handlexikoq, 1911, Vol. II, pp. 21,279; Vol, VIII,p. 112, 1 Handbuch der Organischen Chemie, Vol. I, 4th ed., 1915, p. `860. * Th is Jo t j u n az,, 10,177 (1918). . . * C. A., 17, 1164 (1923), crystals of arabinose hastens crystallization.) Let this cool. After crystallization has; begun add a small volume of ethyl alcohol, being careful not to precipitate an appreciable amount of gummy material. Set thje solution in ithe refrigerator,Ito