ASTM D4904-99 (2020) pdf free.Standard Practice for Cooling of Analytical Solutions.
1.1 This practice covers a standard procedure for the cooling of analytical solutions such as those prepared in Practices D4901, D4905, or D6405. The tannin analysis results for an analytical solution are to some extent dependent on the conditions of the cooling of that solution.
1.2 The values stated in SI units are to be regarded as standard. No other units of measurement are included in this standard.
1.3 This standard does not purport 10 address all of the safety concerns, if anry, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety, health, cand environmental practices and determine the applicability of regulatory limitations prior to use.
1.4 This international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for the Development of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.
2 ASTM Standards:2 D4901 Practice for Preparation of Solution of Liquid Vegetable Tannin Extracts D4905 Practice for Preparation of Solution of Solid, Pasty and Powdered Vegetable Tannin Extracts D6405 Practice for Extraction of Tannins from Raw and Spent Materials.
3. This practice specifies a procedure to follow in cooling to standard or room temperature the hot analytical solutions prepared from tanning materials for Practices D4901, D4905,or D6405.
4. The solubility of extracts is influenced by temperature.The analytical solutions prepared from tanning extracts are dissolved or diluted in hot water. It is necessary to exercise caution in cooling these solutions, and to do so in such a way as to avoid chilling, under- cooling, or uneven cooling of the solutions.
5. The specimen shall be the 1-L or 2-L solutions prepared under Practices D4901, D4905, or D6405.
6. The prepared solutions shall be protected from drafts,and shall be allowed to stand overnight in an ambient temperature of not less than 23 °C, nor more than 28 °C. After their temperature has been adjusted, the solutions shall be made up to the mark with distilled water at 23°C. Where a constant temperature room is available, the solutions, suitably protected from drafts, may be cooled therein with advantage. In this case,the room shall be so controlled that solutions in flasks, exposed therein, shall remain at 24 °C.ASTM D4904 pdf download.