Physical Property Changes in Commercial Natural Rubbers during Long Term Storage

2006 ◽  
Vol 79 (1) ◽  
pp. 72-81 ◽  
Author(s):  
Jintana Yunyongwattanakorn ◽  
Jitladda T. Sakdapipanich
Keyword(s):  
Physical Properties ◽  
Storage Time ◽  
Physical Property ◽  
Gel Content ◽  
Long Term Storage ◽  
Property Changes ◽  
Term Storage ◽  
Clear Relation ◽  
Long Storage

Abstract The physical properties during long term storage of selected commercial Standard Thai Rubbers (STR), i.e. STR XL, STR 5L and STR CV60 as high-graded natural rubber (NR), were investigated. Sections of commercial NR were subjected to examination after storage-hardening. STR 5L showed clearly an increase in Mooney viscosity (VR), Mooney relaxtion (MR30), gel content and initial plasticity (P0), higher than that of STR XL. This result suggests that STR 5L exhibits the highest inconsistency in physical properties. The increasing viscosity and gel content of STR 5L and STR XL samples suggest the occurrence of a crosslink structure during storage. STR CV60, known as a viscosity-stabilized NR sample, also showed an increase in VR, gel content, P0, and high PRI value during long storage. These findings indicate that storage-hardening occurred in the rubber samples even after carefully controlled production procedures. As for the different sections of samples, there was no clear relation with gel content with respect to storage time, indicating that depth or positions of specimens in a certain rubber bale did not affect the storage-hardening phenomenon.

scholarly journals 3′ MACE RNA-sequencing allows for transcriptome profiling in human tissue samples after long-term storage

2020 ◽  
Vol 100 (10) ◽  
pp. 1345-1355 ◽  
Author(s):  
Stefaniya Boneva ◽  
Anja Schlecht ◽  
Daniel Böhringer ◽  
Hans Mittelviefhaus ◽  
Thomas Reinhard ◽  
...  
Keyword(s):  
Rna Sequencing ◽  
Storage Time ◽  
Transcriptome Profiling ◽  
Rna Seq ◽  
Fresh Tissue ◽  
Long Term Storage ◽  
Ffpe Samples ◽  
The Impact ◽  
Term Storage

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.

The Carbonate-Hardening Lime Construction Material Properties Formation during their Long-Term Storage and Use under Normal Conditions

2019 ◽  
Vol 974 ◽  
pp. 187-194 ◽  
Author(s):  
Nikolay V. Lyubomirskiy ◽  
Tamara A. Bakhtina ◽  
Alexander S. Bakhtin ◽  
Sergey I. Fedorkin
Keyword(s):  
Construction Material ◽  
Construction Materials ◽  
Materials Properties ◽  
Long Term Storage ◽  
Efficiency Assessment ◽  
The Stability ◽  
Term Storage ◽  
Long Storage ◽  
Quality Construction

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.

scholarly journals Effects of Long-Term Storage Time and Original Sampling Month on Biobank Plasma Protein Concentrations

EBioMedicine ◽  
2016 ◽  
Vol 12 ◽  
pp. 309-314 ◽  
Author(s):  
Stefan Enroth ◽  
Göran Hallmans ◽  
Kjell Grankvist ◽  
Ulf Gyllensten
Keyword(s):  
Plasma Protein ◽  
Storage Time ◽  
Long Term Storage ◽  
Term Storage

scholarly journals Properties of Fiberboard Overpack Material in the 9975 Shipping Package Following Thermal Aging

2007 ◽  
Author(s):  
W. L. Daugherty
Keyword(s):  
Service Life ◽  
Physical Properties ◽  
Thermal Aging ◽  
Impact Resistance ◽  
Storage Conditions ◽  
Radioactive Material ◽  
Long Term Storage ◽  
Term Storage ◽  
Over Time

Many radioactive material shipping packages incorporate cane fiberboard overpacks for thermal insulation and impact resistance. Mechanical, thermal and physical properties have been measured on cane fiberboard following thermal aging in several temperature/humidity environments. Several of the measured properties change significantly over time in the more severe environments, while other properties are relatively constant. These properties continue to be tracked, with the goal of developing a model for predicting a service life under long-term storage conditions.

scholarly journals Stability of Folate and Vitamin B12in Human Serum after Long-Term Storage: A Follow-Up after 13 Years

2018 ◽  
Vol 2018 ◽  
pp. 1-4 ◽  
Author(s):  
Eugène H. J. M. Jansen ◽  
Piet K. Beekhof
Keyword(s):  
Human Serum ◽  
Storage Time ◽  
Vitamin B ◽  
Serum Samples ◽  
Long Term Storage ◽  
Nutrition Research ◽  
The Stability ◽  
Term Storage

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.

Physical Properties and Volatile Composition Changes of Cooked Sausages Stuffed in a New Casing Formulation Based in Surfactants and Lactic Acid During Long-Term Storage

2017 ◽  
Vol 82 (3) ◽  
pp. 594-604 ◽  
Author(s):  
Chao-Hui Feng ◽  
Cheng Li ◽  
Juan Francisco García-Martín ◽  
Pradeep Kumar Malakar ◽  
Yue Yan ◽  
...  
Keyword(s):  
Lactic Acid ◽  
Physical Properties ◽  
Volatile Composition ◽  
Long Term Storage ◽  
Composition Changes ◽  
Term Storage

A Simple Model for Predicting Heat Aging of EPDM Rubber

2004 ◽  
Vol 77 (2) ◽  
pp. 242-256 ◽  
Author(s):  
Arnis U. Paeglis
Keyword(s):  
Physical Properties ◽  
Strain Energy ◽  
Physical Property ◽  
Elongation At Break ◽  
Epdm Rubber ◽  
Wide Range ◽  
Rate Relationship ◽  
Property Changes ◽  
Simple Empirical Model

Abstract Heat aging stability is a hallmark of EPDM rubber and a requirement for use in automotive, roofing and other applications. Retention of physical properties after accelerated heat aging is a typical specification for such long-term uses. This paper examines the utility of such tests in predicting results over a range of temperatures, 116 °C, 125 °C, 135 °C and 150 °C, in some cases for as long as 365 days. A simple empirical model was developed to predict the retention of physical properties using fractional strain energy, that is, the ratio of the aged to unaged products of tensile strength and elongation at break. Characteristic rates, an Arrhenius rate relationship and activation energies were determined. This model provides a basis to predict physical property changes over a wide range of temperatures and times, as well as for considerations of equivalent heat aging tests and use in different applications.

scholarly journals Ensuring long storage of raw sugar products using electrophysical installation

2021 ◽  
pp. 56-61
Author(s):  
M. A. Yakiyayeva ◽  
A. N. Zhakatayeva ◽  
A. I. Iztayev ◽  
M. M. Маyемеrоv ◽  
B Zh. Muldabekova
Keyword(s):  
Shelf Life ◽  
Experimental Studies ◽  
Sugar Beets ◽  
Sugar Factory ◽  
Long Term Storage ◽  
Raw Sugar ◽  
Term Storage ◽  
Optimal Regimen ◽  
Long Storage

The article examined the efficiency of using an electrophysical installation to ensure the long-term storage of raw sugar products. Experimental studies of sugar beets of the second degree of infection of the Koksu sugar factory. As a result, it was found that in order to increase the shelf life of sugar products, the most optimal regimen is treatment with ozone with a concentration of 8 g/m3 for 20 minutes and an overpressure of 3 or 5 ati.

Viability and Engraftment of Hematopoietic Progenitor Cells (HPC) After Long Term Cryopreservation: Effect of Diagnosis and % Dimethylsulfoxide (DMSO) Concentration.

Blood ◽  
2009 ◽  
Vol 114 (22) ◽  
pp. 3161-3161
Author(s):  
Muthu Kumaran Veeraputhiran ◽  
John Theus ◽  
Gina Pesek ◽  
Bart Barlogie ◽  
Michele H. Cottler-Fox
Keyword(s):  
Storage Time ◽  
Conflicts Of Interest ◽  
Population Data ◽  
T Test ◽  
Hematopoietic Progenitor ◽  
Long Term Storage ◽  
Significant Difference ◽  
Dmso Concentration ◽  
Term Storage

Abstract Abstract 3161 Poster Board III-98 Introduction There are few reports of HPC viability after more than 9 y of storage. It has been suggested that HPC from myeloma patients (pts) may survive storage less well than those from other diseases. The appropriate concentration of DMSO for long term storage is unclear. Our program has collected and stored HPC since November 1989, changing from 5% DMSO to 10% DMSO in August 2000. We present a retrospective analysis of viability by diagnosis and DMSO concentration in pts who underwent autologous transplant using HPC after long-term storage (up to 17.8 y). Materials and Methods HPC were harvested and preserved using a controlled rate freezer and 5% or 10% DMSO, then stored in liquid nitrogen. Viability was tested by flow cytometry using unwashed samples and looking at propidium iodide or 7-AAD uptake within the CD34+ population. Data from 242 samples were analyzed (224 myeloma pts and 18 other diagnoses): 100 consecutively thawed samples with storage time <1 y (all 10% DMSO), 100 consecutive samples stored from 5-9 y ( 7 samples, 10% and 93 samples, 5% DMSO), and all samples stored and used for transplant after >9y (42 samples, 5% DMSO). No statistically significant difference was seen in viability between <1y and 5-9y, so these groups were combined and compared to >9y. White blood cell (WBC) and platelet engraftment were compared for the 2 groups using an unpaired t test. Results Mean viability for the 0-9y and >9 y groups were 91.62% and 92.79% respectively, with no statistically significant difference in viability between groups (p=0.28). Using a 2-tailed t test, no difference was seen in viability based on diagnosis (p=0.19) or between 5% and 10% DMSO (p= 0.12). No difference was seen in WBC engraftment (p=0.28) or platelet engraftment between groups (p=0.57). Discussion HPC collections remained viable after 17.8 years, the longest time reported for use after storage to date. No difference in viability was seen with 5% or 10% DMSO, or between myeloma and other diseases. Storage time did not affect engraftment. Disclosures No relevant conflicts of interest to declare.

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