Prediction of paper permanence by accelerated aging II. Comparison of the predictions with natural aging results

Cellulose ◽  
1996 ◽  
Vol 3 (1) ◽  
pp. 269-279 ◽  
Author(s):  
X. Zou ◽  
T. Uesaka ◽  
N. Gurnagul
Keyword(s):  
Accelerated Aging ◽  
Natural Aging

Accelerated Aging of Deacidified and Untreated Book Paper in 1967 Compared with 52 Years of Natural Aging

2020 ◽  
Vol 41 (3) ◽  
pp. 131-152
Author(s):  
Tali H. Horst ◽  
Richard D. Smith ◽  
Antje Potthast ◽  
Martin A. Hubbe
Keyword(s):  
Room Temperature ◽  
Accelerated Aging ◽  
Natural Aging ◽  
Scanning Electron Micrographs ◽  
Surface Ph ◽  
Room Temperature Storage ◽  
Folding Endurance ◽  
Endurance Tests ◽  
Breaking Length ◽  
Temperature Storage

AbstractThree copies of a book that had been optionally deacidified using two different procedures in 1967, and then subjected to accelerated aging, were tested again after 52 years of natural aging. Matched copies of the book Cooking the Greek Way, which had been printed in Czechoslovakia on acidic paper, were evaluated. Nonaqueous treatment of two of the copies with magnesium methoxide dissolved in chlorofluorocarbon solvent had been found in 1967 to have decreased the susceptibility to embrittlement, as evidenced by the results of the accelerated aging, followed by folding endurance tests. Retesting of the same books in 2019, after 52 years of room temperature storage, showed that the deacidification treatments had achieved the following benefits in comparison to the untreated book: (a) higher brightness; (b) higher folding endurance; (c) tensile breaking length higher in the cross-direction of the paper; (d) substantial alkaline reserve content, (e) an alkaline surface pH in the range 7.1–7.4, and (f) higher molecular mass of the cellulose. Remarkably, some of the folding endurance results matched those of unaged samples evaluated in 1967. Scanning electron micrographs showed no differences between the treated and untreated books.

scholarly journals Altered Nuclear Functions in Progeroid Syndromes: a Paradigm for Aging Research

2009 ◽  
Vol 9 ◽  
pp. 1449-1462 ◽  
Author(s):  
Baomin Li ◽  
Sonali Jog ◽  
Jose Candelario ◽  
Sita Reddy ◽  
Lucio Comai
Keyword(s):  
Werner Syndrome ◽  
Accelerated Aging ◽  
Natural Aging ◽  
Aging Research ◽  
Cellular Processes ◽  
Functional Connections ◽  
Age Related ◽  
Progeroid Syndromes ◽  
Progeria Syndrome ◽  
Hutchinson Gilford Progeria Syndrome

Syndromes of accelerated aging could provide an entry point for identifying and dissecting the cellular pathways that are involved in the development of age-related pathologies in the general population. However, their usefulness for aging research has been controversial, as it has been argued that these diseases do not faithfully reflect the process of natural aging. Here we review recent findings on the molecular basis of two progeroid diseases, Werner syndrome (WS) and Hutchinson-Gilford progeria syndrome (HGPS), and highlight functional connections to cellular processes that may contribute to normal aging.

scholarly journals One-Step Reinforcement and Deacidification of Paper Documents: Application of Lewis Base—Chitosan Nanoparticle Coatings and Analytical Characterization

Coatings ◽  
2020 ◽  
Vol 10 (12) ◽  
pp. 1226
Author(s):  
Zhihui Jia ◽  
Chun Yang ◽  
Fangnan Zhao ◽  
Xiaolian Chao ◽  
Yuhu Li ◽  
...  
Keyword(s):  
Photoelectron Spectroscopy ◽  
Chitosan Nanoparticles ◽  
Antibacterial Properties ◽  
Interaction Mechanism ◽  
Accelerated Aging ◽  
Natural Aging ◽  
Lewis Base ◽  
X Ray ◽  
Chitosan Nanoparticle ◽  
One Step

To delay acidification and deterioration during natural aging, deacidification and reinforcement of paper manuscripts have been the most important technologies to prolong the life of objects. Herein, a novel approach for the conservation of paper manuscripts is proposed using chitosan nanoparticles as Lewis base that leads to both deacidification and strengthening of paper in one-step. Chitosan nanoparticles were prepared through physical ball grinding method and characterized via scanning electron microscopy (SEM), X-ray diffraction (XRD), laser particle size analyzer (LPSA), Fourier transform infrared spectroscopy (FTIR), and atomic force microscope (AFM). To evaluate the resistance of chitosan nanoparticle coating, the mechanical properties of paper after artificial aging were evaluated using dry heat and hygrothermal accelerated aging methods. The SEM, EDX, and X-ray Photoelectron Spectroscopy (XPS) were used to analyze the interaction mechanism between chitosan and Shuxuan paper. The results show that the coated paper had superior durability with respect to pH, tensile strength, and folding endurance. There was a presence of protonated amines in the form of ammonium salts due to ionic bindings with free H+ in the acidified paper, and the remaining –NH2 could be used as a base reserve. Finally, the resulting coated papers displayed good antibacterial properties.

Accelerated Aging of Vulcanized Rubber. Factors Determining the Relation between Oven and Bomb Aging

1947 ◽  
Vol 20 (3) ◽  
pp. 760-768 ◽  
Author(s):  
R. G. Newton ◽  
J. R. Scott
Keyword(s):  
Accelerated Aging ◽  
Natural Aging ◽  
Relative Importance ◽  
Temperature Coefficients ◽  
Vulcanized Rubber ◽  
Relative Response ◽  
Aging Conditions ◽  
Moderate Range ◽  
Natural Rubber Vulcanizates ◽  
Theoretical Considerations

Abstract A study has been made of the influence of the following factors on the relative rates of tensile deterioration of natural rubber vulcanizates in the Geer oven and oxygen bomb, both at 70° C : period of vulcanization, sulfur ratio, nature of accelerator. Expressing this relation as the oven/bomb ratio, i.e., the ratio between oven and bomb aging periods that give the same deterioration, the following conclusions are drawn. (1) Varying the period of vulcanization of a given mix over a moderate range (2:3) around the optimum does not noticeably alter the oven/bomb ratio, except in unaccelerated mixes, where overvulcanization gave an abnormally low ratio, owing to the rubber perishing very rapidly in the oven. (2) The effect of varying the sulfur ratio within the usual limits for soft rubbers is small, and appears to result from the quicker vulcanization of the mixes richer in sulfur. (3) The nature of the accelerator profoundly affects the ratio, values ranging from 3 to 27 being found among the present mixes ; this effect is believed to be exerted through the influence of the accelerator both on rate of vulcanization and on the oxidizability of the vulcanizate. Theoretical considerations indicate that a rubber which vulcanizes quickly and (or) oxidizes slowly should give a low oven/bomb ratio, whereas one that vulcanizes slowly and(or) oxidizes quickly should give a higher ratio. The experimental data are generally in accord with this, and there is evidence that both rate of vulcanization and oxidizability can have an important effect, but the data do not enable the separate effect of each to be assessed exactly. The bearing of the results on the use of the oven and bomb tests is briefly discussed. It is shown that they demonstrate the fallacy of using a single factor for converting oven to bomb aging periods or vice versa, and that the relative natural aging resistances of widely different vulcanizates cannot be reliably assessed by either test, a limitation arising from the fact that the relative importance of oxidative decay and aftervulcanization varies from one type of mix to another, and that the temperature coefficients of these processes are not necessarily the same. These facts are very important in relation to the choice and application of accelerated aging tests for specification purposes, since these usually have to be applied to rubbers of unknown compositions, which are likely to vary widely in their relative response to different aging conditions.

scholarly journals Quantitative Trait Locus Mapping of Seed Vigor in Soybean under −20 °C Storage and Accelerated Aging Conditions via RAD Sequencing

2021 ◽  
Vol 43 (3) ◽  
pp. 1977-1996
Author(s):  
Rongfan Wang ◽  
Fengqi Wu ◽  
Xianrong Xie ◽  
Cunyi Yang
Keyword(s):  
Quantitative Trait ◽  
Accelerated Aging ◽  
Natural Aging ◽  
Storage Conditions ◽  
Seed Vigor ◽  
C Storage ◽  
Poor Seed ◽  
Aging Conditions ◽  
Trait Locus ◽  
Locus Mapping

Due to its fast deterioration, soybean (Glycine max L.) has an inherently poor seed vigor. Vigor loss occurring during storage is one of the main obstacles to soybean production in the tropics. To analyze the genetic background of seed vigor, soybean seeds of a recombinant inbred line (RIL) population derived from the cross between Zhonghuang24 (ZH24, low vigor cultivar) and Huaxia3hao (HX3, vigorous cultivar) were utilized to identify the quantitative trait loci (QTLs) underlying the seed vigor under −20 °C conservation and accelerated aging conditions. According to the linkage analysis, multiple seed vigor-related QTLs were identified under both −20 °C and accelerated aging storage. Two major QTLs and eight QTL hotspots localized on chromosomes 3, 6, 9, 11, 15, 16, 17, and 19 were detected that were associated with seed vigor across two storage conditions. The indicators of seed vigor did not correlate well between the two aging treatments, and no common QTLs were detected in RIL populations stored in two conditions. These results indicated that deterioration under accelerated aging conditions was not reflective of natural aging at −20 °C. Additionally, we suggest 15 promising candidate genes that could possibly determine the seed vigor in soybeans, which would help explore the mechanisms responsible for maintaining high seed vigor.

Accelerated aging of commercial papers in dry air, compared with natural aging

1973 ◽  
Author(s):  
E J Parks ◽  
R L Hebert ◽  
Catherine Feasenmyer
Keyword(s):  
Accelerated Aging ◽  
Natural Aging ◽  
Dry Air

Influence of Packaging on the Preservation of Consumer Properties of Soft Drinks During Storage

2021 ◽  
pp. 43-46
Author(s):  
Ирина Львовна Ковалева ◽  
Ольга Александровна Соболева ◽  
Елена Михайловна Севостьянова
Keyword(s):  
Shelf Life ◽  
Raw Materials ◽  
Soft Drink ◽  
Accelerated Aging ◽  
Natural Aging ◽  
Soft Drinks ◽  
Significant Deterioration ◽  
Plant Raw Materials ◽  
Organoleptic Characteristics ◽  
Physico Chemical

В настоящей статье рассматривается зависимость устанавливаемого срока годности безалкогольных напитков от вида потребительской упаковки и ее влияние на сохранность потребительских свойств. В качестве объектов исследования были выбраны безалкогольные газированные напитки на растительном сырье двух наименований. Каждый продукт был расфасован в два вида упаковки - в стеклянную бутылку и в ПЭТ. Опытные образцы подвергли ускоренному старению. Все измерения проводили на 10, 20 и 30 сут. эксперимента, что соответствует 4, 8 и 12 мес. естественного старения. Показатели безопасности образцов в течение и после окончания эксперимента соответствовали требуемым нормам. Было отмечено плавное снижение потребительских свойств напитков, упакованных в стеклянные бутылки. При этом через 30 сут эксперимента (12 мес. естественного старения) физико-химические показатели соответствовали контрольным образцам в пределах допускаемых отклонений. Некоторое ухудшение органолептических характеристик наблюдали лишь к концу заявленного производителем срока годности 12 мес. В напитках, расфасованных в ПЭТ-упаковку, наблюдали более резкое снижение потребительских свойств. При этом производитель заявляет срок их годности также 12 мес. Но уже через 20 сут эксперимента (8 мес. естественного старения) содержание СО2 не соответствовало заявленному производителем. Одновременно было отмечено значительное ухудшение органолептических характеристик. Также было выявлено появление постороннего привкуса в этих образцах, обусловленное, в том числе, приростом содержания ацетальдегида в процессе эксперимента. Проведенные исследования показали, что устанавливая срок годности безалкогольного напитка, производители должны учитывать не только тип, группу и способ обработки напитков, но и вид упаковки, который они используют. This article examines the dependence of the established shelf life of soft drinks on the type of consumer packaging and its impact on the preservation of consumer properties. As the objects of research, two names of soft carbonated drinks based on plant raw materials were selected. Each product was packaged in two types of packaging - in a glass bottle and in PET. Samples underwent accelerated aging. All measurements were carried out on days 10, 20 and 30 of the experiment, which corresponds to 4, 8 and 12 months of natural aging. The safety indicators of the samples during the experiment and after its completion corresponded to the required standards. There was a gradual decline in the consumer properties of beverages packaged in glass bottles. At the same time, after 30 days of the experiment (12 months of natural aging), the physico-chemical indicators corresponded to the control samples within the limits of permissible deviations. Some deterioration in organoleptic characteristics was observed only by the end of the stated shelf life of 12 months. Drinks packaged in PET showed a sharper decrease in consumer properties. At the same time, the manufacturer declares their shelf life is also 12 months. But after 20 days of the experiment (8 months of natural aging), the CO2 content did not correspond to the manufacturer's declared one. At the same time, a significant deterioration in organoleptic characteristics was noted. The appearance of off-flavor in these samples was also revealed. This is explained, among other things, by the increase in the content of acetaldehyde during the experiment. Studies have shown that when setting the shelf life of a soft drink, manufacturers must take into account not only the type, group and way of processing the drinks, but also the type of packaging they use.

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