Suitability of Flash Media for the Long-Term Storage of Information

Author(s):  
Joe Iraci

Abstract Flash storage media such as memory cards and USB flash drives are now commonly used to transfer and store information. However, little is known about the long-term stability of this type of media and this is a concern for archives and other institutions as they begin to receive content stored on these devices. In this study, the stabilities of a variety of different flash media were examined. The evaluation was performed by using accelerated ageing at 85 °C and 85 % relative humidity (RH) and 125 °C for ageing intervals up to 2000 hours. Measurements were also performed on samples previously subjected to accelerated ageing and then naturally aged for five years to verify the results from the accelerated ageing experiments. Overall, the stability of flash media was very good. For many of the samples, no read errors were encountered after accelerated or natural ageing. However, for several of the high capacity flash card samples and USB flash drives, significant decreases in read speed were noted. This can be problematic because it will eventually lead to read errors. It was established that for the USB samples this instability was likely attributed to the use of the less stable TLC (triple-level cell) memory chip.

2021 ◽  
pp. 875512252098521
Author(s):  
Peter R. Chai ◽  
Georgia Goodman ◽  
Majo J. Bustamante ◽  
Yassir Mohamed ◽  
Jose Castillo-Mancilla ◽  
...  

Background: Digital pill systems comprise an ingestible sensor integrated into a gelatin capsule that overencapsulates medication allowing real-time measures of medication ingestion. These systems may improve the manner in which medication adherence can be assessed and supported. Objective: In this investigation, we tested the durability of the ingestible sensor as part of a clinical trial to measure the feasibility and acceptability of the system to measure adherence to once daily tenofovir disoproxil fumarate/emtricitabine (NCT03842436). Methods: Digital pills not dispensed during the study were stored in a pharmacy. Seventeen sensors were selected from digital pills stored for at least 12 months and activated in a simulated gastric environment. A radiofrequency spectrum analyzer and the reader device used in the clinical trial to capture ingestion events were used to measure activation of emitters. A passing evaluation was defined as an energized emitter within 30 minutes of immersion, ability to broadcast a signal for 10 minutes, and successful acquisition by the reader. Results: All ingestible sensors passed the stability test. Mean activation time in simulated gastric fluid was 3.33 minutes (SD = 1.47); emitters remained active for a mean of 47.72 minutes (SD = 1.78). These parameters matched guidelines defined in the ID-Cap system requirements for use in patients. Conclusions: Ingestible sensor components of the ID-Cap system were therefore stable after long-term storage.


Author(s):  
Joe Iraci

Abstract The most recent generation of optical disc media available is the Blu-ray format. Blu-rays offer significantly more storage capacity than compact discs (CDs) and digital versatile discs (DVDs) and thus are an attractive option for the storage of large image or audio and video files. However, uncertainty exists on the stability and longevity of Blu-ray discs and the literature does not contain much information on these topics. In this study, the stabilities of Blu-ray formats such as read-only movie discs as well as many different brands of recordable and erasable media were evaluated. Testing involved the exposure of samples to conditions of 80 °C and 85 % relative humidity for intervals up to 84 days. Overall, the stability of the Blu-ray formats was poor with many discs significantly degraded after only 21 days of accelerated ageing. In addition to large increases in error rates, many discs showed easily identifiable visible degradation in several different forms. In a comparison with other optical disc formats examined previously, Blu-ray stability ranked very low. Other data from the study indicated that recording Blu-ray media with low initial error rates is challenging for some brands at this time, which is a factor that ultimately affects longevity.


2017 ◽  
Vol 2017 ◽  
pp. 1-7 ◽  
Author(s):  
Pavlina Holcapkova ◽  
Zuzana Kolarova Raskova ◽  
Martina Hrabalikova ◽  
Alexandra Salakova ◽  
Jan Drbohlav ◽  
...  

This work describes novel alternative for extraction of bacteriocin nisin from a whey fermentation media and its stabilization by using polyethylene glycol as matrix with high practical applicability. This product was compared with commercially available nisin product stabilized by sodium chloride and nisin extracted and stabilized by using ammonium sulfate and polysorbate 80. The stability of samples was tested by means of long-term storage at −18, 4, 25, and 55°C up to 165 days. The nisin content in the samples was determined by high-performance liquid chromatography and electrophoresis. In addition, effect of whey fortification with lactose on nisin production and antibacterial activity studied against Staphylococcus aureus was tested. Results show that stabilization by polyethylene glycol provides enhanced nisin activity at 55°C after 14 days and long-term stability at 25°C with keeping antibacterial activity.


2008 ◽  
Vol 1 (1) ◽  
pp. 67-78 ◽  
Author(s):  
M. Hafner ◽  
M. Sulyok ◽  
R. Schuhmacher ◽  
C. Crews ◽  
R. Krska

In this paper the stability and degree of epimerisation of six major ergot alkaloids at three different temperature levels (-20 °C, +4 °C and +20 °C) over periods of 18 hours and six weeks is reported for the first time. The behaviour of ergometrine, ergocornine, ergocristine, α-ergocryptine, ergosine and ergotamine was thoroughly studied in seven solvents which are employed for the preparation of calibrants and extraction mixtures, respectively. Moreover, the stability of the ergot alkaloids was tested in different cereal extracts (rye, wheat, barley, oats) for 1, 2 and 6 days. Of the toxins tested, the ergopeptide-type toxins ergosine, ergotamine, ergocornine, α-ergocryptine and ergocristine showed similar behaviour patterns. The simple lysergic acid derivative ergometrine was more stable and showed hardly any epimerisation to ergometrinine, with the sum of both epimers remaining constant in all seven solvents. The ergopeptides tested show variable epimerisation tendencies, and were also less stable during six weeks at 20 °C. Ergosine showed the highest degree of epimerisation (43% after 6 weeks at 20 °C). In general, the order of epimerisation promotion was methanol/dichloromethane > acetonitrile/buffer > extraction mix > stabilising solution > acetonitrile >> chloroform. Long-term storage at room temperature can only be carried out in chloroform, which showed no epimerisation for all toxins even at 20 °C and also kept the sum of R and S forms constant, which indicates no formation of aci-epimers or other degradation products. Long-term storage of ergot alkaloids in acetonitrile, the most convenient solvent with respect to HPLC analysis, should be carried out at temperatures of -20 °C or below. The constant epimer ratio of all ergot alkaloids in the extraction mixture acetonitrile/ammonium carbonate buffer (200 mg/l; 92:8, v/v) during an HPLC run (18 hours) demonstrates the stability of the toxins in this extraction mixture.


2019 ◽  
Vol 974 ◽  
pp. 187-194 ◽  
Author(s):  
Nikolay V. Lyubomirskiy ◽  
Tamara A. Bakhtina ◽  
Alexander S. Bakhtin ◽  
Sergey I. Fedorkin

This paper presents the lime binding forced carbonate-hardening materials properties formation study and determins the stability of these properties during long-term storage and use under normal conditions. The tests showed these materials stability properties over time, confirming the strength and density growth of the test samples after long storage due to the calcium hydroxide recrystallization completion into calcium carbonate processes. Also, the results of the samples carbonate hardening study under natural conditions during 18 months are presented. An efficiency assessment of forced carbonate hardening as one of the methods of recycling technogenic CO2 in order to reduce its emissions in the atmosphere, and, in the result, to obtain high-quality construction materials has been made.


2017 ◽  
Vol 35 (1) ◽  
pp. 11-31 ◽  
Author(s):  
David Stuart Holmes Rosenthal

Purpose Increasingly, the content that libraries collect is no longer on paper, a long-lived, medium whose technology changes very slowly and with which they have centuries of experience. Instead, it is stored on relatively short-lived digital media whose technology appears to change rapidly and with which they have little history. The paper aims to discuss this issue. Design/methodology/approach The storage media industry is highly competitive and is currently evolving rapidly as flash, a solid state medium, displaces spinning disk from many applications. Long-term archival storage is a small part of the total storage market. It typically re-uses media and systems intended for more general bulk storage. Findings What are the medium-term prospects for change in this market? Originality/value Much of this material has appeared in blog posts and talks aimed at storage experts, such as the recent DARPA workshop on future of storage. It is presented here for a librarian audience with the necessary additional exposition and background.


2020 ◽  
Vol 20 (11) ◽  
pp. 6855-6861
Author(s):  
Wooram Kim ◽  
Mijeong Park ◽  
Jong-Ki Jeon ◽  
Youngmin Jo

Dinitramide anion [−N(NO2)2] salt composed of resonance structure is a plausible oxidizing agents, as efficient propellant. Among them, guanidinium dinitramide (GDN) is an organic compound improving the stability against moisture, as well long term storage. An additional advantage composed guanidinium ion is the reaction efficient via the decomposed by-product during pyrognostics, maximum yield of 99%. The types of GDN (GDN-I, II, III, IV, V) were synthesized using several starting material such as guanidine acetate, chloride, carbonate, nitrate and sulfate under hydrodeprivation. In this work, the intermediates formed in these processes were closely identified and their thermal properties, and chemical structure were examined. The absorption peaks by Fourier transform infrared (FT-IR) were found guanidinium infrared frequencies (3452, 3402, 3354, 3278, 1642 cm−1) and dinitramide infrared frequencies (3208, 1570, 1492, 1416, 1337, 1179, 1000 cm−1). The activation energy of GDN samples were obtained Ea = 53.26 Kcal/mole (GDN-I), 50.94 Kcal/mole (GDN-II), 52.34 Kcal/mole (GDN-III), 62.19 Kcal/mole (GDN-IV), 55.32 Kcal/mole (GDN-V) from exothermic at over 153°C.


2018 ◽  
Vol 2018 ◽  
pp. 1-4 ◽  
Author(s):  
Eugène H. J. M. Jansen ◽  
Piet K. Beekhof

In epidemiological and nutrition research, it is very important to evaluate the stability of biomarkers as function of both storage time and temperature. In this study, the stability of folate and vitamin B12in human serum samples has been tested after long-term storage at −80°C up to 13 years. Serum samples of 16 individuals were used in this study. The concentration of folate and vitamin B12has been determined att=0and at 1, 8, and 13 years after storage at −80°C. The folate concentrations in serum samples remained stable at −80°C. The concentration of vitamin B12was decreasing during the time of the study to about 50%. The correlation of the folate and also of the vitamin B12concentrations in the stored samples compared with the starting values was still good. Therefore, although the concentration of vitamin B12decreased upon storage, reliable comparative analyses can still be performed.


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