Storage life tests

Assuming that a certain explosive bolts conducted accelerated storage life test under three temperature stress as 60°C, 71°C, 80°C, and Arrhenius model was chosen as the accelerated model. Samples and detecting time in the test process was shown in Table 1. 

Table 1. Sample size and time for explosive blot accelerated storage life test.

Zhao Wan, Research on the Step Stress Accelerated Storage Life Test Method of Space Pyrotechnic Devices [J]. 2008(3)i20--23. 

Zhao Wan, Tian-long HAN. Optimum Design Method of the Accelerated Storage Life Test for Pyrotechnics Based on Activation Energy [J]. Chinese journal of energetic materials, 2009(4) 475-477. 

The MUF resin pH was determined using pH meter model pH 340-A/SET l-MTM. The pH meter was calibrated before it was used to determine the pH of the resin. The viscosity was determined using the Cole-Parmer 98936-15 viscometer (R2 spindle, lOOrpm speed). The storage life was a test of shelf life of the MUF resin under the ambient environment. Resin was first stored at ambient room temperature. Viscosity of the resin was checked for every three to four days. The ratio of water that can be added into resin before it turned turbid or precipitated is called resin solubility. The resin solubility was determined by divide the weight of resin and the weight of water added into resin before it turned turbid or precipitated. The curing period of a resin was defined as the time period for the resin to be hardened after application in a 30°C and 1.0% of NH4CI powder (as hardener). 

A prediction of useful life for solid propellant rockets is quite important, from the standpoint of operational readiness and economic considerations. The premature removal and replacement of deployed systems, based on inaccurate storage life estimates, can be costly. A specific missile system and propellant combination could become obsolete while long term storage data are being compiled. Accelerated aging tests are normally used to give qualitative indications of storability, but the deficiencies of these tests are obvious and are discussed later. 

Other routine tests made on commercial systems include storage (shelf life) tests, assessment under conditions of environmental and mechanical stress, etc. The behaviour of cells under conditions of continuous short circuit and after complete discharge must also be characterized. Testing procedures for particular cell systems are outlined in subsequent chapters. 

The so-called storage stability test is a standard test that is used across many different fields—e.g., the pharmaceutical, cosmetic, and food industries. The test is popular because it yields precise information about the long-term shelf life of emulsions. In this test, emulsions are stored under conditions that are applicable to those encountered in the actual production/consumption situation. It should be noted that the presented test protocol is time consuming and requires sampling over an extended period of time. In the... 

This example demonstrates that storage stability tests are extremely useful as they allow emulsion manufacturers to accurately follow even small changes in emulsion properties. Plots of droplet size distribution and concentration as a function of time can be used to determine the kinetics of the instability process and to determine the shelf life of the product by setting upper and lower limits for both mean droplet size and concentration at each port. 

ASTM D 1337 describes a standard test method for measuring storage life of adhesives by... 

D 1337 Test Method for Storage Life of Adhesive by Consistency and Bond Strength... 

Radiation also is an important tool in the medical treatment of cancer. However, what may be one of its most important applications, extending the storage life of foods, has been seriously delayed by public concern, in spite of extensive tests showing that irradiated foods meet all international safety standards. Currently, the United States irradiates spices for the main purpose of bug removal. 

More often we are not interested so much in the exact rate of decomposition as we are in how a particular explosive compares to others in its storage life. For that purpose, much simpler tests are run, such as the thermal stability tests. 

Barbier, J.W., Hanhela, P.J., Huang, R.H. and Paul, D.B. (1990) Effect of temperature on storage life of polysulfide aircraft sealants. Polymer Testing, 9(5), 291-313. 

Table I). With the browning inhibitor formulations tested, the pressure treatment added about 1 week to the storage life of the samples at the higher concentration, and 3 or 4 days at the lower concentration, compared to dipping at atmospheric pressure. 

ASLT (accelerated shelf life testing) must also be run on the sensor and its individual components to define realistic shelf life, storage conditions, and usage conditions. This information is also critical to the overall quality control for the sensor and the instructions for its use. 

Expiration claims could be documented by real-time shelf life testing, however, the timelines for product development would be adversely affected. The developers of the ISO 11607 standard recognized this hindrance and therefore have allowed that accelerated aging tests may be undertaken in addition to real-time aging tests by storage under conditions of increased severity. This provision is beneficial however, no guidance is provided as to what conditions of adverse severity are permissible or technically reliable. It therefore has become crucial that guidance and standards be provided to help manufacturers establish product shelf life and expiration claims. 

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