Obsolescence Management & the Impact on Reliability

2012 ◽  
Vol 2012 (1) ◽  
pp. 000591-000597
Author(s):  
Cheryl Tulkoff ◽  
Greg Caswell

Component obsolescence management is a strategic practice that also mitigates the risk of counterfeit parts. Left unchecked, obsolescence issues increase support, development and production costs. So, planning ahead is critical. For companies that do proactively manage component availability and obsolescence, the effect of long-term storage on manufacturability and reliability is the area of major concern. Many issues can arise depending on the component technology and storage environment. Reliability concerns to consider include solderability, stress driven diffusive voiding, moisture, Kirkendall voiding, intermetallics/oxidation and tin whiskering. When component obsolescence isn't planned for, the secondary market is often the supply chain of last recourse. While it is possible to get high quality, genuine parts, it is also possible to get nonconforming, reworked, or counterfeit components. And, it is increasingly difficult to differentiate genuine parts from their counterfeit equivalents. Historically, the secondary market provided a mechanism for finding parts in short supply or at reduced cost. Today, high-reliability system manufacturers are less willing to risk contamination of their supply chain with potentially substandard parts in order to save a few dollars on the cost of a part. This paper will cover obsolescence management strategies, relevant industry standards, use of managed supply programs (MSP) and contract pooled options, plus long term storage recommendations and practices.

Metabolites ◽  
2018 ◽  
Vol 8 (4) ◽  
pp. 93 ◽  
Author(s):  
Cora McHugh ◽  
Thomas Flott ◽  
Casey Schooff ◽  
Zyad Smiley ◽  
Michael Puskarich ◽  
...  

Background: Though blood is an excellent biofluid for metabolomics, proteins and lipids present in blood can interfere with 1d-1H NMR spectra and disrupt quantification of metabolites. Here, we present effective macromolecule removal strategies for serum and whole blood (WB) samples. Methods: A variety of macromolecule removal strategies were compared in both WB and serum, along with tests of ultrafiltration alone and in combination with precipitation methods. Results: In healthy human serum, methanol:chloroform:water extraction with ultrafiltration was compared to methanol precipitation with and without ultrafiltration. Methods were tested in healthy pooled human serum, and in serum from patients with sepsis. Effects of long-term storage at −80 °C were tested to explore the impact of macromolecule removal strategy on serum from different conditions. In WB a variety of extraction strategies were tested in two types of WB (from pigs and baboons) to examine the impact of macromolecule removal strategies on different samples. Conclusions: In healthy human serum methanol precipitation of serum with ultrafiltration was superior, but was similar in recovery and variance to methanol:chloroform:water extraction with ultrafiltration in pooled serum from patients with sepsis. In WB, high quality, quantifiable spectra were obtained with the use of a methanol: chloroform precipitation.


2020 ◽  
Vol 100 (10) ◽  
pp. 1345-1355 ◽  
Author(s):  
Stefaniya Boneva ◽  
Anja Schlecht ◽  
Daniel Böhringer ◽  
Hans Mittelviefhaus ◽  
Thomas Reinhard ◽  
...  

Abstract This study aims to compare the potential of standard RNA-sequencing (RNA-Seq) and 3′ massive analysis of c-DNA ends (MACE) RNA-sequencing for the analysis of fresh tissue and describes transcriptome profiling of formalin-fixed paraffin-embedded (FFPE) archival human samples by MACE. To compare MACE to standard RNA-Seq on fresh tissue, four healthy conjunctiva from four subjects were collected during vitreoretinal surgery, halved and immediately transferred to RNA lysis buffer without prior fixation and then processed for either standard RNA-Seq or MACE RNA-Seq analysis. To assess the impact of FFPE preparation on MACE, a third part was fixed in formalin and processed for paraffin embedding, and its transcriptional profile was compared with the unfixed specimens analyzed by MACE. To investigate the impact of FFPE storage time on MACE results, 24 FFPE-treated conjunctival samples from 24 patients were analyzed as well. Nineteen thousand six hundred fifty-nine transcribed genes were detected by both MACE and standard RNA-Seq on fresh tissue, while 3251 and 2213 transcripts were identified explicitly by MACE or RNA-Seq, respectively. Standard RNA-Seq tended to yield longer detected transcripts more often than MACE technology despite normalization, indicating that the MACE technology is less susceptible to a length bias. FFPE processing revealed negligible effects on MACE sequencing results. Several quality-control measurements showed that long-term storage in paraffin did not decrease the diversity of MACE libraries. We noted a nonlinear relation between storage time and the number of raw reads with an accelerated decrease within the first 1000 days in paraffin, while the numbers remained relatively stable in older samples. Interestingly, the number of transcribed genes detected was independent on FFPE storage time. RNA of sufficient quality and quantity can be extracted from FFPE samples to obtain comprehensive transcriptome profiling using MACE technology. We thus present MACE as a novel opportunity for utilizing FFPE samples stored in histological archives.


2016 ◽  
Vol 688 ◽  
pp. 10-16
Author(s):  
Blažej Seman ◽  
Anton Geffert ◽  
Jarmila Geffertova

Wood is loosely stored to ensure continuous production inside paper mills where it is exposed to the effect of external factors. The impact of storage leads to some changes of mechanical and physical properties of wood, but these changes are not the same in all specimens. In this paper, it has been observed that the long term storage of wood influences the impact strength in bending and the permeability of wood for fluids. During the storage, there was a decrease of impact strength in bending of poplar heartwood by 28.3% and oak by 22.1% and mature beech wood by 37.3%. Also, there was decreased a permeability of wood, poplar sapwood 18.3 % and heartwood of 53.9%; oak sapwood by 20.0% and heartwood by 20.3%; beech sapwood 45.8% and mature wood by 48.2%. By decrease of the observed properties of the stored wood, a deterioration a quality of produced pulp can be expected (a higher Kappa number, amount reject and decrease the mechanical properties of pulp).


2021 ◽  
Vol 14 (1) ◽  
pp. 96-105
Author(s):  
V. V. Suskin ◽  
◽  
I. V. Kapyrin ◽  
F. V. Grigorev ◽  
◽  
...  

The article evaluates the impact of a “buried wall” barrier on the long-term safety during the long-term storage1 or in-situ disposal of nuclear legacy facilities, in particular, industrial reservoirs, as well as during the development of near-surface disposal facilities for radioactive waste (RWDF). For assessment purposes, filtration and mass transfer processes have been numerically modelled in the GeRa code based on a case study of a reference near-surface facility. The study explores in which way the available covering screen affects the dynamics of contaminant spread. It evaluates the sensitivity of the results to the dispersion parameter commonly characterized by a high degree of uncertainty.


Author(s):  
Narendra K. Gupta

Drum type packages are routinely used to transport radioactive material (RAM) in the U.S. Department of Energy (DOE) complex. These packages are designed to meet the federal regulations described in 10 CFR 71. In recent years, there has been a greater need to use these packagings to store the excess fissile material, especially plutonium for long term storage. While the design requirements for safe transportation of these packagings are well defined, the requirements for safe long term storage are not well established. Since the RAM contents in the packagings produce decay heat, it is important that they are stored carefully to prevent overheating of the containment vessel (CV) seals to prevent any leakage and the impact limiter to maintain the package structural integrity. This paper analyzes different storage arrays for a typical 9977 packaging for thermal considerations and makes recommendations for their safe storage under normal operating conditions.


2014 ◽  
Vol 670-671 ◽  
pp. 376-381 ◽  
Author(s):  
Aleksey Adamtsevich ◽  
Aleksey Eremin ◽  
Andrey Pustovgar ◽  
Stanislav Pashkevich ◽  
Sergey Nefedov

This article is a stage of the author’s research into the impact of different factors on the hydration of mineral binders. The problem of cement activity decrease due to adsorption moisture influence during long-term storage in normal conditions (20°C and 50% RH) was examined. The influence of storage period in airtight and non-airtight conditions on the kinetics of heat evolution during hydration as well as on phase composition of Portland cement was characterized using experimental methods.


PLoS ONE ◽  
2022 ◽  
Vol 17 (1) ◽  
pp. e0262275
Author(s):  
Stephan Hilpmann ◽  
Miriam Bader ◽  
Robin Steudtner ◽  
Katharina Müller ◽  
Thorsten Stumpf ◽  
...  

The safe disposal of high-level radioactive waste in a deep geological repository is a huge social and technical challenge. So far, one of the less considered factors needed for a long-term risk assessment, is the impact of microorganisms occurring in the different host rocks. Even under the harsh conditions of salt formations different bacterial and archaeal species were found, e. g. Halobacterium sp. GP5 1–1, which has been isolated from a German rock salt sample. The interactions of this archaeon with uranium(VI), one of the radionuclides of major concern for the long-term storage of high-level radioactive waste, were investigated. Different spectroscopic techniques, as well as microscopy, were used to examine the occurring mechanisms on a molecular level leading to a more profound process understanding. Batch experiments with different uranium(VI) concentrations showed that the interaction is not only a simple, but a more complex combination of different processes. With the help of in situ attenuated total reflection Fourier-transform infrared spectroscopy the association of uranium(VI) onto carboxylate groups was verified. In addition, time-resolved laser-induced luminescence spectroscopy revealed the formation of phosphate and carboxylate species within the cell pellets as a function of the uranium(VI) concentration and incubation time. The association behavior differs from another very closely related halophilic archaeon, especially with regard to uranium(VI) concentrations. This clearly demonstrates the importance of studying the interactions of different, at first sight very similar, microorganisms with uranium(VI). This work provides new insights into the microbe-uranium(VI) interactions at highly saline conditions relevant to the long-term storage of radioactive waste in rock salt.


Author(s):  
В.О. ГОРОДЕЦКИЙ ◽  
С.О. СЕМЕНИХИН ◽  
Н.М. ДАИШЕВА ◽  
Н.И. КОТЛЯРЕВСКАЯ ◽  
М.М. УСМАНОВ

Величина неучтенных потерь сахара в России составляет 0,06–0,14 млн т в год, что обусловливает необходимость внедрения мероприятий по их снижению. В статье представлены результаты исследований по снижению микробиологической обсемененности диффузионного сока, очищенного сока II сатурации и сиропа, выведенного на длительное хранение. Рассмотрены причины, обусловливающие обсемененность корнеплодов сахарной свеклы патогенными микроорганизмами. Приведена методика постановки лабораторных исследований. Установлено, что на стадии обработки экстрагента применение сернистого ангидрида позволяет снизить обсемененность диффузионного сока МАФАнМ и плесневыми грибами на 41,75 и 40,26% соответственно. На стадии обработки фильтрованного сока II сатурации применение сернистого ангидрида снижает обсемененность сока МАФАнМ на 76,67% и практически полностью обеспечивает угнетение плесневых грибов. На стадии обработки сиропа применение сернистого ангидрида позволяет снизить обсемененность сиропа после длительного хранения МАФАнМ и плесневыми грибами на 68,97 и 58,33% соответственно, тогда как применение бисульфита натрия – только на 31,03 и 33,33% соответственно. На основании результатов исследований сделан обоснованный вывод, что обработка полупродуктов свеклосахарного производства сульфитсодержащими реагентами, а именно сернистым ангидридом, является эффективным технологическим приемом для обеспечения снижения неучтенных потерь сахарозы, возникающих в результате жизнедеятельности микроорганизмов. The value of unaccounted sugar losses in Russia is 0,06–0,14 million tons per year, which makes it necessary to implement measures to reduce them. The article presents the results of studies to reduce the microbiological contamination of diffusion juice, purified juice of the and syrup removed for long-term storage. The reasons for the contamination of sugar beet root crops with pathogenic microorganisms are considered. The method of setting up laboratory tests is given. It was found that at the stage of processing the extractant, the use of sulfurous anhydride reduces the contamination of the diffusion juice with MAFAnM and mold fungi by 41,75 and 40,26%, respectively. At the stage of processing filtered juice of second carbonation, the use of sulfur dioxide reduces the contamination of MAFAnM juice by 76,67% and almost completely suppresses mold fungi. At the syrup processing stage, the use of sulfurous anhydride reduces the contamination of the syrup after long-term storage by MAFAnM and mold fungi by 68,97 and 58,33%, respectively, while the use of sodium bisulfite – only by 31,03 and 33,33%, respectively. Based on the results obtained, a reasonable conclusion is made that the treatment of beet sugar production intermediates with sulfite-containing reagents, namely, sulfur anhydride, is an effective technological technique to ensure the reduction of unaccounted losses of sucrose resulting from the vital activity of microorganisms.


2017 ◽  
Vol 76 (6) ◽  
pp. 1332-1346 ◽  
Author(s):  
Nicholas A. O'Connor ◽  
Aravind Surapaneni ◽  
David Smith ◽  
Daryl Stevens

Reuse of sewage biosolids in Victoria, Australia, typically involves mesophilic anaerobic digestion followed by air-drying and long-term storage to ensure removal of ova of soil-transmitted helminths (STH) such as Ascaris lumbricoides. Long-term storage degrades the biosolids' agronomic quality due to the loss of key plant nutrients and takes up large areas of storage space. The impact of varying biosolids holding times and other processes on STH using Ascaris as the reference STH pathogen was examined in this study using a quantitative risk analysis approach. Risk modelling of the potential human health impacts from the presence of Ascaris ova in biosolids was undertaken for discrete holding periods of 1, 2 and 3 years. Modelling showed that to meet the WHO 1 μDALY·person−1·year−1 disease burdens guideline for limiting exposure category, a biosolids storage period of 1.24 years or 2.1 years would be required, depending on the data source of ova shedding rates per worm (Bangladesh or Nigeria, respectively). The soil exposure and salad/root vegetable consumption models included a number of variables with moderate to high degrees of uncertainty. Monte Carlo simulation was used to assess the effect of uncertainty in model input variables and to assist in highlighting areas for further research.


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