Circular of the National Bureau of Standards, Issue 440U.S. Government Printing Office, 1942 |
From inside the book
Results 1-5 of 100
Page 23
... alcohol , brought to a boil , and stirred while adding 0.525 g of iodine as a 20- percent solution in alcohol . Stirring is continued while a jell forms . and until the mass has cooled . The herapathite is rapidly precipitated out of ...
... alcohol , brought to a boil , and stirred while adding 0.525 g of iodine as a 20- percent solution in alcohol . Stirring is continued while a jell forms . and until the mass has cooled . The herapathite is rapidly precipitated out of ...
Page 116
... alcohol or ether from an atomizer . To obtain good definition while making up to volume , the bottom of the meniscus should be made to appear dark by a reflection of the finger or of a section of rubber tubing placed a few millimeters ...
... alcohol or ether from an atomizer . To obtain good definition while making up to volume , the bottom of the meniscus should be made to appear dark by a reflection of the finger or of a section of rubber tubing placed a few millimeters ...
Page 148
... alcohol and 50 ml of absolute ether by first adding the alcohol to the cotton , allowing the mixture to stand in a stoppered flask for 10 minutes , adding the ether , and shaking . Allow the solution to stand overnight , pour about 100 ...
... alcohol and 50 ml of absolute ether by first adding the alcohol to the cotton , allowing the mixture to stand in a stoppered flask for 10 minutes , adding the ether , and shaking . Allow the solution to stand overnight , pour about 100 ...
Page 161
... alcohol to break the foam , if necessary . Make to 500 ml at 20 ° Č , mix , and filter . Delead the filtrate with the minimum of powdered ammonium dihydrogen phosphate , and filter , using a little filter aid if desired . Polarize in a ...
... alcohol to break the foam , if necessary . Make to 500 ml at 20 ° Č , mix , and filter . Delead the filtrate with the minimum of powdered ammonium dihydrogen phosphate , and filter , using a little filter aid if desired . Polarize in a ...
Page 162
... alcohol should be added , since it is optically active . Cover filters during filtration , and discard the first 10 to 15 ml of each filtrate . No more ammonium phosphate than necessary should be used , since 1 g per 100 ml depresses ...
... alcohol should be added , since it is optically active . Cover filters during filtration , and discard the first 10 to 15 ml of each filtrate . No more ammonium phosphate than necessary should be used , since 1 g per 100 ml depresses ...
Contents
1 | |
2 | |
3 | |
17 | |
18 | |
27 | |
33 | |
41 | |
586 | |
587 | |
588 | |
589 | |
590 | |
591 | |
592 | |
593 | |
47 | |
53 | |
57 | |
64 | |
80 | |
90 | |
115 | |
145 | |
152 | |
164 | |
165 | |
192 | |
199 | |
201 | |
208 | |
212 | |
217 | |
223 | |
232 | |
241 | |
259 | |
262 | |
272 | |
279 | |
284 | |
293 | |
295 | |
300 | |
311 | |
312 | |
316 | |
324 | |
326 | |
336 | |
349 | |
368 | |
374 | |
384 | |
390 | |
398 | |
405 | |
406 | |
411 | |
435 | |
445 | |
455 | |
482 | |
483 | |
513 | |
535 | |
541 | |
543 | |
546 | |
551 | |
562 | |
563 | |
564 | |
576 | |
584 | |
594 | |
596 | |
597 | |
599 | |
601 | |
602 | |
603 | |
604 | |
605 | |
606 | |
607 | |
608 | |
609 | |
610 | |
612 | |
613 | |
614 | |
624 | |
625 | |
627 | |
632 | |
642 | |
643 | |
644 | |
647 | |
648 | |
650 | |
652 | |
657 | |
658 | |
662 | |
663 | |
664 | |
666 | |
670 | |
671 | |
672 | |
673 | |
674 | |
676 | |
677 | |
679 | |
680 | |
683 | |
690 | |
691 | |
692 | |
694 | |
696 | |
702 | |
703 | |
704 | |
762 | |
766 | |
767 | |
781 | |
800 | |
810 | |
Other editions - View all
Common terms and phrases
acetate added alpha amount analysis analyzer apparatus aqueous azimuth beaker beam beta boiling Brix Bureau of Standards calcium calculated cell CH₂OH Chem chloride coefficient color components concentration configuration constant containing cooled copper correction crystalline crystals decolorizing carbon determined deut dextrose dilute direction dissolved distilled electrode equation equilibrium evaporated FIGURE filter filtrate flask galactose glass glycosides grams HCOH heating hydrochloric acid hydrogen hydrolysis instrument invert sugar invertase Isbell lactose lamp levulose liquid measurements mercury method methyl alcohol mixture modifications molasses mutarotation nicol nicol prism normal weight obtained optical rotation oscillation oxide percent plane polarized polariscope polarized light potassium precipitate prism procedure pyranose quantity quartz quartz control plates raffinose reaction reducing sugars refracting saccharimeter sample sirup sodium sodium hydroxide solubility specific rotation sucrose sugar solution sulfate sulfuric acid temperature thickness tion titration tube turbidity vacuo volume washed wave length
Popular passages
Page 382 - NOTE. — For the purpose of interpreting these specifications the following definitions apply: The total length is the over-all length of the finished instrument. The diameter is that measured with a ring gage. The length of the bulb is the distance from the bottom of the bulb to the beginning of the enamel backing. The top of the thermometer is the top of the finished instrument.
Page 158 - If the analyst is in doubt as to the completion of the hydrolysis, allow a portion of the solution to remain for several hours and again polarize. If there is no change from the previous reading, the inversion is complete, and the reading and temperature of the solution should be carefully noted.
Page 181 - Titrate at once with the thiosulphate solution until the brown tinge has become weak, then add sufficient starch liquor to produce a marked blue coloration. Continue the titration cautiously until the color due to free iodin has entirely vanished.
Page 768 - ... to test the correctness of saccharimeters ; for those who execute commercial analyses, the repeated control of the instruments is to be accomplished, now as before, by quartz plates. 4. In effecting the polarization of substances containing sugar, half-shade instruments, or triple field, only are to be employed.
Page 177 - By consulting the table it will be seen that the vertical column headed 150 is nearest to Z, 145, and the horizontal column headed 95 : 5 is nearest to the ratio of R to I, 95.1 : 4.9.
Page 782 - ... not imported to be commercially used for the extraction of sugar, or for human consumption...
Page 776 - After bringing the solution exactly to the mark at the proper temperature, and after wiping out the neck of the flask with filter paper, pour all of the wellshaken clarified sugar solution on a rapidly acting filter. Reject the first portions of the filtrate and use the rest, which must be perfectly clear for polarization.
Page 667 - If the number is less than 1, make the characteristic of the logarithm negative, and one unit more than the number of zeros between the decimal point and the first significant figure of the given number.
Page 789 - ... test of the importation and also the quantity and test of each lot from which such average test is obtained.
Page 787 - Receptacles — How sampled. — Sugar in hogsheads and other wooden packages shall be sampled by putting the long trier diagonally through the package from chime to chime, one trierful to constitute a sample, except in small lots, when an equal number of trierfuls shall be taken from each package to furnish the required amount of sugar necessary to make a sufficient sample. In the sampling of baskets, bags, seroons, and mats the short trier shall be used, care being exercised to have each sample...