1、MIL-L-48765 (AR) Amendment 2 Superseding Amendment 1 25 September 78 MILITARY SPECIFICATION LITHIUM HEXAFLUORORSENATE This Amendment forms a part of Military Specification MIL-L-48765 (AR) dated 19 June 1975. Page 1 Delete II (PA) II wherever it appears and .substitute “ (AR) Delete the Preamble and
2、 substitute the following: “This specification approved for use by the US Army Armament Research and Development Command and is available for use by all Departments and Agencies of the Department of Defense“. Page. 2 Para. 3.1.2. X-ray diffraction. Delete Table I in its entirety and substitute the f
3、ollowing: “Table I Peak, d-value (decreasing order of intensity) 3.30 - 3.70. 4.40 - 4.65 2.90 - 3.10 . 1.65 - 1.76 Para. 3.1.3 2nfra-red spectroscopy. Add the following“ “This requirement may be used as an alternate to x-ray diffraction requirement given in 3.1.2.“ Page 3 Para 3.1.4 Impurities - De
4、lete the last sentence in paragraph. FSC: 6810 fi c i3 t- - B c Provided by IHSNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-MIL-L-48765 (2) 68 = 7779906 OL2L202 b W MIL-L-48765 (AR) Amendment 2 Delete Table III in its entirety and substitute the following Table
5、III: Table III Immrities Total Halogens Water Maximum Allowable Test Concen tr at i.on, PPM Paragraph 50 150 4.4.3.6 4.4.3.10 Para. 3.1.5 Properties; Delete Hydrolysis/Dehvdration and Particle Size Requirement in their entirety and change “Potential“ to “Potentiometric Value“. Page 5 Para. 4.4.2 Tes
6、ting. At the end of the sentence add the following: “At a Reiative Humidity not to exceed 4% at ambient conditions:. Para. 4.4.2.1 Sampling. The following changes shall be made: Ist sentence. D elete “1 pound“ and substitute “100 grams“. 2nd sentence. At the end of the sentence add the following: “o
7、r the samples from each batch that is combined into a shipping lot shall be subjected to the tests listed below in accordance with MIL-STD-105. Level II.“ Table - Delete Table in its entirety and substitute the following Table V. “Table V Inspection/Requirement Form & Color (see 3.1.1) X-ray Diffrac
8、tion (see 3.l.2) or Infra-red Spectroscopy (see 3.1.3) Total Halogens (see 3.1.4) Water (see 3.l.4) pH (see 3.1.S) Solubility in MF (see 3.1.5) Potentiometric Value (see 3.1.5) (Al terna te Met hod ) Page 2 of 7 Defect C1.assj.f icat ion Major Major Major Major Major Major Major Major“ Provided by I
9、HSNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-HIL-L-4765 (2) b = 7773706 01123202 MIL-L-48765 (AR) Amendment 2 Page 6 Para 4.4.3.1 Form. Delete the first sentence and Substitute the following sentence: “Spread the sample on a flat surface and examine the materi
10、al microscopically (at a 25X magnification) for the presence of contamination and form. Paragraphs 4.4.3.4, 4.4.3.5, 4.4.3.7, 4.4.3.8, 4.4.3.9, 4.4.3.13 and 4.4.3.14 - Delete these paragraphs in their entirety. Page 7 Para. 4.4.3.11 m. Make the following changes to this paragraph: Ist Sentence: Prep
11、are a 1 Molar .g iven in ASTM-E70“ delete in its entirety and substitute: “Prepare a 1 Molar solution of the LiAsfg by dissolving 195.86g of the sample in a liter of boiled distilled water (pH 6-7) and determine the pH of the resultant solution in accordance with the method given in ASTM-E70. The pH
12、 measurement should be taken immediately following preparation of the solution, with reading taken between 1 and 3 minutes following preparation. 3rd Sentence: Delete “distilled water“ and substitute: “boiled distilled water (PH 6-7) .II 4th Sentence: At end-of sentence add “the pH measurement shall
13、 be taken immediately following preparation of the solution,with readings taken between 1 and 3 minutes following preparation. 5th Sentence: “The pH measurement.for a least 10 minutes period“ delete this sentence in its entirety. Page 8 Para 4.4.3.14 Particle Size. Delete this paragraph iq its entir
14、ety . Para 4.4.3.15 Potentiometric Value. Substitute the following met hod : “4.4.3.6 Haloqens: Delete in its entirety and substitute the i following: Page 3 of 7 Provided by IHSNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-MIL-L-48765 (AR) Amendment 2 “4.4.3.6 T
15、otal Halogens. Determine the halogens present in the compound using a spectrophotometric described in the literature or reference textbook (see 6.4) . “4.4.3.15 Potentiometric Value The potentiometric value (EMF) shall be checked on a 2 molar solution of the sample in methyl formate (see 4.4.3.11).
16、4.4.3.15.1 Equipment a) Platinum electrode - Beckman Model 39273 bright inlaid b) Saturated Calomel Electrode (SCE) and associated salt platinum electrode. .or equivalent. bridge prepared in accordance with following procedures or equivalent. i) Preparation of Saturated Calomel Electrode (SCE) Equip
17、ment a) 50 ml erlenmeyer flask b) Double distilled mercury e) Potassium chloride (KC1) certified ACS grade d) Calomel (Hg2C12) - certified ACS grade e) Mortar and pestle f) 250 ml bottle Procedure Step 1: Thoroughly clean a 50 ml erlenmeyer Step 2: Place sufficient mercury (double dis- Step 3: Prepa
18、re 200 ml of a saturated solution Step 4: To the above solution add about 2 grams flask with chromic acid cleaning solu- tion, rinse with water and dry, tilled) to form a layer 1 cm deep in the bottom of the flask. of KC1. of calomel (HgC12) and shake vig- erously so as to obtain a saturated solutio
19、n. It is best to prepare this solution a day in advance. Page 4 of 7 Provided by IHSNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-MIL-L-48765 (2) 68 7977906 CIL21204 1 Step 5: Step 6: Step 7: Step 8: Step 9: MIL-L-49765 (AR) Amendment 2 . Place a few drops of mer
20、ucury in a mortar and add approximately 7 grams of calomel, moisten with a few drops of the above calomel-saturated KC1 solution and grind together until the mixture has a decided black or grayish black appearance. Wash the mixture several times by de- cantation with the clear supernatant liquid fro
21、m the calomel saturated KC1 solution. After the last decantation, transfer a sufficient amount of the mixture to form a 0.5 cm layer on top of the mercury. Add the remaining portion of the cal- omel-saturated KC1 solution to the cell until it is about two-thirds full. Seal a 3-4 inch piece of platin
22、um wire into a soft glass tube taking care that the seal does not leak. This is then inserted in a rubber stopper and adjusted so that the platinum wire is completely submerged below the surface of the mercury. 2) Preparation of Salt Bridge Equipment :2 a) Agar - laboratory grade b) Potassium chlori
23、de (KC1) - certified ACS c) 6-8 mm glass tubing d) 200 ml beaker grade. Procedur e Step 1: Heat 3 grams of agar in 100 ml of Step 2: Add 30 grams of KC1 and stir until water on a steam bath with stirring until the solution is clear. dis solved Page 5 of 7 t - - . Provided by IHSNot for ResaleNo repr
24、oduction or networking permitted without license from IHS-,-,-MIL-L-48765 (2) 68 7777906 OL2L205 3 . . . . MIL-L-48765 (AR) i Step 3: Suck the above solution into a 6-8 mm i glass tube which has been bent to the i l Amendment 2 desired configuration. ting, the glass is cut back with a file to expose
25、 it. of the salt bridge in a IN KC1 solution. . Step 4: If shrinkage of the gel occurs on set- Step 5: When not in use, store the exposed end I c) Two volt - One amp regulated ower supply d) High impedance voltmeter (1015 ohms or greater) equipped with recorder e) Graphite rod electrode 4.4.3.15.2 P
26、rocedure Step 1: Step 2: Step 3: Step 4: Step 5: Step 6: Clean the platinum electrode in concen- trated nitric acid and rinse well with distilled or deionized water. Immerse the electrode in a 1N solution of nitric acid and connect to the posi- tive terminal of a constant potential power supply. Con
27、nect the negative terminal to a graphite rod also immersed ! in the acid solution. Set the voltage at 2.0 volts and activate the power supply for 1.0 minutes. Oxygen should be evolved freely at the electrode surface. Turn off the power supply and reverse the polarity of the electrodes. Reactivate fo
28、r a period of 20 - 90 minutes at a voltage of 2.0 volts. Hydrogen must be evolved at the surface of the electrode throughout the entire cathodization pro- cess. If hydrogen evolution should cease, repeat the entire treatment pro- cess and if the problem is not corrected, the electrode shall be consi
29、dered unsat- isfactory and replaced. Remove the electrode from the acid solu- tion, rinse well with distilled or deionized water and then turn off the power supply. Dry the electrode in a stream of cool air. Page 6 of 7 Provided by IHSNot for ResaleNo reproduction or networking permitted without lic
30、ense from IHS-,-,-Step 7: Step 8: Step 9: Step 10: Step 11: MIL-L-48765 (AR) Amendment 2 Rinse the tip of the calomel electrod.es salt bridge with distilled or deionized water and dry in a stream of cool air. Connect the electrodes to a high impe- dance voltmeter ohms or greater) equipped with a rec
31、order. Immerse the electrodes in a small beaker containing the test solution and activate the voltmeter and recorder. This mea- surement may be done under normal atmos- pheric conditions but the solution must be kept in a sealed container until the time of the measurement. Take the reading 400 secon
32、ds after the immersion of the electrodes. A certain amount of drift can be expected but the reading should be rekatively stable after 400 seconds. If excessive drift is still occuring after this period ( 0.3 mv/ sec), the measurement shall be considered void. Repeat the above procedure until five va
33、lues have been obtained and then average these values. A fresh sample shall be used for each measurement. “The margins of this amendment are marked with an asterisk to indicate where changes (additions, modifications, corrections, deletions) from the previous amendment were made. This was done as a
34、convenience.only and the Government assumes no liability whatsoever for any inaccuracies in these notations. Bidders and contractors are cautioned to evaluate the require- ments of this document based on the entire content irrespective of the marginal notations and relationship to the last previous amendment. I Custodian: Army-AR Preparing Activity Project No. 6810 AB02 Army-AR Page 7 of 7 *V.C. GOVERNMENT PR INTI NG OFFICE: 1980-603-1 21/1007 Provided by IHSNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-
