Aging and Durability

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Catalytic Performance Degradation Characteristics and Characterization of CDPF in Laboratory Hydrothermal Aging and Diesel Vehicle Durability Aging

Catalytic Performance Degradation Characteristics and Characterization of CDPF in Laboratory Hydrothermal Aging and Diesel Vehicle Durability Aging

Table 2 shows the cell constant of the sample calculated by the Debye-Scherrer formula. The crystallinity of Fresh, Aged and Used samples are 76.15%, 76.16% and 79.22% respectively. Compared with Fresh samples, Aged samples had no change, and the cell parameters and cell volume of Aged samples decreased. However, the crystallinity of Used samples increases obviously, the cell parameter alpha increases, while the cell volume decreases and the cell parameter beta decreases. It shows that Used samples has new crystalline phase formation, and the average lattice parameter of the whole sample decreases. The results of XRD analysis of CDPF show that the crystallinity of Used samples is higher than Fresh and Aged samples. On the one hand, the crystallinity of Used samples is increased because the precious metal oxides, metal oxides, residual soot and ash are divided into new crystalline phases in the aging process; On the other hand, the temperature of CDPF in the regeneration process may reach 800~900 ℃, and in the aging process, the frequency of regeneration is relatively frequent, which is easy to cause the carrier grain growth, the crystal shape tends to be complete, increasing the crystallinity of the diesel vehicle durability aging sample, also shows that the CDPF deterioration degree of diesel vehicle durability test is stronger than that of laboratory hydrothermal aging.

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Probabilistic durability evaluation of binary and ternary concrete 
		mixtures considering aging effect

Probabilistic durability evaluation of binary and ternary concrete mixtures considering aging effect

Due to the aim of comparing the durability and probability assessment, there are shown results from both possibilities. The results confirms that the concrete mixture with average reference diffusion coefficient and high aging factor have better long term probabilistic durability compared to mixtures with lower aging factor.

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Evaluating the durability of wood-based panels using internal bond strength results from accelerated aging treatments

Evaluating the durability of wood-based panels using internal bond strength results from accelerated aging treatments

The four groups of commercial wood-based panels used in this study, PB, MDF, OSB, and PW, are widely used for construction purposes in Japan (Table 1). Each panel group included two panel types of differing specifi cations giving eight panels in total. The PB panels were made from recy- cled wood with different binders. The MDF panels differed in thickness, binder type, and end-use application. The OSB panels used were imported products made from different wood species. The plywood panels also differed in thickness. Because the OSB used in this project was obtained from North America and Europe, these panels are not necessarily representative of the OSB typically used in Japan. Although North America has very little MDI-bonded PB or MDF, MDI-bonded PB and MDF were selected because fabrica- tors in Japan show a strong preference for PB and MDF to achieve high durability. The parallel direction on each panel surface was defi ned by the machine direction for PB and MDF, the surface strand alignment for OSB, and the surface veneer grain direction for plywood. In total, 22 original panels (100 cm × 200 cm) were prepared for each panel type. These were cut to sample panels (30 cm × 30 cm), and then we randomly selected 24 panels for accelerated aging tests and the outdoor exposure test. The mechanical proper- ties of the panels before aging treatments were summarized in a previous article. 22

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Evaluation of wood-based panel durability using bending properties after accelerated aging treatments

Evaluation of wood-based panel durability using bending properties after accelerated aging treatments

Abstract The durability of wood-based panels was evalu- ated by comparing the bending properties of panels sub- jected to fi ve accelerated aging treatments with the bending properties of panels that had experienced 5 years of outdoor exposure in Shizuoka City, Japan. In each accelerated aging treatment, methylene diphenyl diisocyanate-bonded panels showed higher bending retention than phenol formalde- hyde (PF)-bonded panels. The bending retentions after six repeated cycles of the JIS-B, APA D-1, and ASTM treat- ments showed a correspondence of nearly one-to-one in the data for the three different treatments. The Shizuoka City 5-year outdoor exposure test data showed that the bending retentions of all panels decreased with time. In particular, the bending retentions of PF resin-bonded particleboard and oriented strandboard made from aspen were less than 30% and 10% of the original values, respectively, after the 5-year exposure period. The deterioration of the bending properties after the 5-year outdoor exposure in Shizuoka City was the same as that for six repetitions of the ASTM treatment.

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Increasing of Durability of Cutting Tools

Increasing of Durability of Cutting Tools

In the current mass production of various goods resulting from the globalization of produc- tion, the final costs of the production are highly influenced by the tools used in the production of the steel sheet cut-outs. The tools should not only provide high quality of the cut-out parts (shape and size stability of the components), but also high durability of the active parts of the cutting tools. Low durability of the cutting tools makes manufacturers often interrupt the production pro- cess [1, 9, 14]. However, the re-adjustment of the tools after the re-grinding process requires signif- icant amount of time and well-qualified people.

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Evaluation of the Effect of Oxidative Aging on Asphalt Mixtures for Pavement Performance Prediction.

Evaluation of the Effect of Oxidative Aging on Asphalt Mixtures for Pavement Performance Prediction.

The Arrhenius equation, presented as Equation 1-1 in this report, describes the temperature dependency of the oxidation rate. Herrington et al. (1994) proposed Equation 1-2 through Equation 1-4 for modeling the oxidation kinetics of asphalt binder using viscosity as an AIP. Herrington et al.’s (1994) kinetics model considers both the initial fast reaction period (i.e., the spurt) and the constant rate period. Researchers at Texas A&M University also conducted a series of projects that led to a kinetics model, as expressed in Equation 1-3 through Equation 1-8, using similar principles and the same Arrhenius equation as Herrington et al. (1994) (Lau et al. 1992, Davison et al. 1994, Liu et al. 1996, Domke et al. 2000, Glover et al. 2014). In the Texas A&M University kinetics model, the carbonyl area is used as the AIP. In addition, Glover et al. (2014) presented an interrelationship among kinetics parameters to describe the fast and constant rate reactions. Glover et al. (2005) developed interrelationships between Arrhenius parameters of fast and constant rates, as shown in Equation 6 through Equation 8. This simplification reduced the number of unknowns to only two parameters in addition to the short-term aged binder CA. In addition, Glaser et al. (2013b) used stoichiometry and mathematics to derive the kinetics model given in Equation 1-9 using C+S absorbance peaks as an AIP. Their kinetics model has only one adjustable parameter besides short-term aged binder aging level, which implies that the kinetics model can be calibrated using isothermal aging. They validated their model using 12 asphalt binders from a wide variety of sources. Equation 1-3 and Equation 1-4 are applied along with Glaser et al.’s (2013b) model to describe the temperature dependency of the oxidation reaction. Glaser et al. (2013b) proposed that the kinetics of asphalt binder can be modeled using a single material-dependent parameter that corresponds to the quantity of reactive material within an asphalt, M, and proposed that the Arrhenius parameters, kf and kc, are the same for all

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Investigating the Influence of Precipitation Hardening and Characterization of Aluminium Alloy Composite Material

Investigating the Influence of Precipitation Hardening and Characterization of Aluminium Alloy Composite Material

Aging behaviour (C2) has more hardness than compared to aging behaviors are C1 and C3. From this diagram the most hardness value is 152 BHN. Aging parameter C2 (solutionzing time-3hrs, aging temperature-170°C, aging hours-5 hrs.) is more influence of the hardness than the age behaviour of C1 and C3.Aging parameter (C2) of tensile strength is 9.21%, 5.26% increased compare to aging parameter (C1) and aging parameter (C3).

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Review of Accerlated Thermal Aging Models of Conditioning Assessment of Power Transformer Insulation

Review of Accerlated Thermal Aging Models of Conditioning Assessment of Power Transformer Insulation

ABSTRACT: Oil immersed power transformer being very important and highly expensive is main backbone and hub of power transmission & distribution system. Its failure not solely causes its own harm but directly affect the protection, stability and reliability of the power grid system. A power transformer needs to be tested periodically for its protection and safe operation. These test include routine test, temperature rise test, dielectric type tests, short circuit withstand test, sound level test, insulation monitoring tests, impulse test, field service test etc. Transformer reliability is totally dependent on these test results. A vital decision regarding transformer diagnostic and condition monitoring is made on basis of these test results. But, it's well known proven fact that all of the desired tests mustn't be performed on a power transformer in commission because a number of these tests are harmful in nature. Because of test results of these experiments are essential in diagnostic and observance procedure for transformers in actual operating conditions. Therefore, so as to perform these tests, scaled-down or prorated models of actual power transformers are utilized in experimental studies. This paper presents the various models, experimental setups and numerous methodologies are used till date to work out the aging issue of transformer insulation system.

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The effect of Yb3+ on corrosion of lead oxychloride tellurite glasses

The effect of Yb3+ on corrosion of lead oxychloride tellurite glasses

One of the important factors in material selection is their chemical durability. This characteristic will determine the quality of the material. Corrosion can be defined as the chemical or electrochemical reaction between a material and its environment that produces deterioration of the material and its properties.

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Experiencing aging or demystifying myths? – impact of different “geriatrics and gerontology” teaching strategies in first year medical students

Experiencing aging or demystifying myths? – impact of different “geriatrics and gerontology” teaching strategies in first year medical students

These findings can be explained by the fact that in “Experiencing Aging”, students experience the functional limitation associated with aging [27–29], and thus are able to put themselves in the shoes of the elderly, thereby increasing their empathy. However, owing to the simulation of the limitations and disabilities (visual diffi- culty, disabilities, among others), it is likely that this worsened students’ attitudes toward the elderly, deeming them incapable of managing their lives due to the nu- merous limitations demonstrated in the activity. These results are similar to the findings of a previous investiga- tion [30], but conflict with other studies that found posi- tive or neutral results after using this same strategy [8, 31]. In our view, because this activity was introduced at the beginning of the course (students were not yet famil- iar with the subject and held many stereotypes regarding the elderly), it may have strengthened the myths of aging leading to the decline in attitude. Perhaps if imple- mented among students with greater knowledge in the area of geriatrics and gerontology, results may have been different, as suggested by some studies in doctors and students with more years of “experiencing aging” [32].

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Laboratory Aging of Modern Mixtures to Simulate Field Aging.

Laboratory Aging of Modern Mixtures to Simulate Field Aging.

Factors such as weather patterns vary throughout the seasons and years and have a profound effect on the aging of asphalt pavement. Temperature shifts result in contraction and expansion of the pavement, as well as creating rutting and cracking damage. Moisture can damage a pavement without proper drainage and will cause erosion. As the temperature increases, the rate of oxidation also increases. Temperature can affect the rate of oxidation, the type of binder species that are oxidized, and the nature of the oxidized species that are formed. If the temperature is too high, the asphalt binder could age in a way that results in a fundamentally different binder than aged binder at a lower temperature (Kim et al. 2018). All of these factors contribute to the aging of asphalt pavement. Souza and Castro conducted a study on how these factors affect pavement aging and performance and created a computational finite element model to predict the mechanical response of pavement for temperature shifts and repeated traffic

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Responding to the Needs of Aging Pupulation

Responding to the Needs of Aging Pupulation

Aging of Population In Iran: In Islamic Republic of Iran, the median age of population has increased during last decades. Official statistics show this figure has raised in the interval of 1976-996 from 16.8 to 19.4 years, and it will increase to 32 years until 2020 (Delavar et al, 2003). Similar increas- es have occurred in life expectancy at birth of Iranian people, too. The people expected to live nearly 40 years in 1950s, now would expect to live around 70 years (Amani, 1999). The Iranian elderly female / male ratio is 46/54. This ratio is at con- trast with the fact that women live longer than men. Perhaps, inade- quate health care of pregnant

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Lactobacillus acidophilus DDS 1 modulates the gut microbiota and improves metabolic profiles in aging mice

Lactobacillus acidophilus DDS 1 modulates the gut microbiota and improves metabolic profiles in aging mice

To the best of our knowledge, this is the first detailed study that demonstrates an integrated pattern recognition approach to understand the changes in the aging gut by exploring the metabolic network with and without probiotic supplementation. The key metabolic pathways identified by MetPA and MSEA play an important role in probiotic-induced gut microbiota-associated metabolic changes. Understanding the complex nature of specific gut microbiome and metabolome of the mouse, our study corroborates previous findings of gut microbiota shifts in aging could result in significant alterations in metabolic phenotype of the host with relevance to human health [2,5,47,54]. Any specific change to metabolic phenotype may lead to various GI and metabolic disorders [17,53,54]. The current model of probiotic-induced gut microbial and metabolic profiling is largely explained by a multi-omics approach using fecal 16S rRNA sequencing analysis and metabolomics [70]. Our results suggest that the aging-associated shifts in gut microbiota can be modulated by the dietary intervention of L. acidophilus DDS-1. In particular, this intervention enriched a number of beneficial bacteria, such as Akkermansia, Allobaculum, and Lactobacillus spp. in the gut, and directly contributed to the improvement of the host metabolic phenotype [8]. Translation of these outcomes to clinical accessibility warrants furthers larger mouse cohorts with extreme older mice before clinical studies. Indeed, DDS-1 intervention intended to selectively promote bacteria could become a vital dietary strategy to counteract aging-associated dysbiosis.

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Durability of Indium Tin Oxide Silver Indium Tin Oxide Films against Moisture Investigated Through The Wettability of The Top Oxide Layer

Durability of Indium Tin Oxide Silver Indium Tin Oxide Films against Moisture Investigated Through The Wettability of The Top Oxide Layer

As shown in the Fig. 3, only Ag and Ag(Ti) films deposited on the ITO substrates were also subjected to the test of durability against moisture for 144 hours. After the testing, there were several cavities formed on the surface of the Ag film. It could be due to the moisture-induced migration of Ag atoms as proposed by E. Ando and et al. 4) On the contrary, the Ag(Ti) film could maintain completive and continuous surface after the testing. It evidences that the doping Ti can effectively restrain the moisture-induced migration of Ag atoms and inhibit the agglomeration of the silver layer. That could lead the improvement of durability of ITO-Ag(Ti)-ITO films.

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Studying of Heat Treatment Influence on Corrosion Behavior of AA6061-T6 by Taguchi Method

Studying of Heat Treatment Influence on Corrosion Behavior of AA6061-T6 by Taguchi Method

The data given in Table 7 shows that contribution of NaCl concentration (97.4%) is more than the sum of the contributions of all the other three parameters (2.6%). Also, the contribution of aging temperature is more than aging time. It is evident from Tables 6 and 7 that ANOVA analysis not only specifies how important a parameter is to the corrosion resistance of coatings by numbers but also shows their relative effect. By ranking their relative contributions, the sequence of the four parameters affecting the corrosion resistance is NaCl concentration, aging temperature, aging time and quenching environment. It is also worthwhile mentioning that, in the ANOVA analysis, if the percentage error (P e ) contribution to the total variance is

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Testing the Mutation Accumulation Theory of Aging Using Bioinformatic Tools

Testing the Mutation Accumulation Theory of Aging Using Bioinformatic Tools

The turn of the twentieth century saw prominent biologists addressing the is- sue of aging. Ilya Ilyich Mechnikov, a prominent Russian biologist and a Nobel laureate for the discovery of phagocytes (macrophages) in 1908, was one of the first biologists to address the issue of aging and he is the one to coin the terms Geriatrics and Gerontology from the Greek word Geras for old age. Since then, many theories for aging were put forward. Some backed by more evidence than others. The free radical theory and DNA damage theory are two of the older ones. In the free radical theory, accumulative damage that underlies senescence is brought on by free radicals with time, hence, calorie restriction and the in- crease in consumption of anti-oxidant for an individual can be said to increase longevity [1]. The DNA damage theory suggests breaks in the DNA and other mechanical damage to the DNA and what they ensue on the cellular machinery to be the main culprit of aging. Much evidence was put forward for other theo- ries to take shape; programmed longevity theory suggests aging to be a similar phenomenon to development where the expression of genes alters with time changing with it the phenotypic traits of the individual; the endocrine theory suggests hormonal changes to be a contributing factor to aging [2].

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Durability of glass and ceramic fibres within the lung

Durability of glass and ceramic fibres within the lung

compositions in Gamble's fluid and for certain compositions in distilled water. The more recent work of Scholze and Conradt (1987) ignores the use of exposure fluids other than Gamble's fluid altogether, to produce a "durability ranking" of a range of inorganic fibrous materials during Gamble's fluid exposure. No attempt was made to explain the differences in durability of the test samples or why only Gamble's fluid was used. Furthermore, localised corrosion associated with the intimate packing of the fibres in this system may be possible.

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Implementation of an active aging model in Mexico for prevention and control of chronic diseases in the elderly

Implementation of an active aging model in Mexico for prevention and control of chronic diseases in the elderly

The fundamental objective of GHC is to prevent and detect the diseases of greatest prevalence in the elderly, such as high blood pressure, diabetes mellitus, depres- sion, osteoarthrosis, cognitive deterioration, and oste- oporosis, as well as establishing actions of healthy aging for the maintenance, prolongation, and recuperation of physical, mental, and social functionality (Figure 4). The active aging program also seeks to improve the self-per- ception of psychosocial well-being, considering the eld- erly adult's physical condition and sociocultural environment. Thus, control programs should be imple- mented for the healthy and the ill older adult, with pre- established evaluation, surveillance, and primary health care actions. These actions should be performed by previ- ously trained older adults who are coordinated by GPs, who are in turn supported and supervised by the PGHCU. Gerontological Orientation for Families (GOF)

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A systematic review of aging and its causes

A systematic review of aging and its causes

Aging is the accumulation of detriment which may lead to decline in normal function on cellular, tissue or organ level that ultimately causes age-related diseases and death over time (Gkogkolou and Böhm, 2012). Many diseases involved in aging, including diabetes, atherosclerosis, osteoporosis and rheumatoid arthritis, are caused by pathophysiology of free radical formation, dysfunction of innate and adaptive immunity and DNA repair process (Dunn and Koo, 2013). Genetics, endogenous (intrinsic) and environmental (extrinsic) factors play major role in complex process of aging (Vierkötter and Krutmann, 2012; Viña et al., 2007). The complex natural process of skin aging is impacted by intrinsic (genetics, metabolic pathways and hormones) and extrinsic (chronic UV radiation exposure, pollution, cigarette smoke, chemicals, toxins) factors (Bernhard et al., 2007; Ganceviciene et al., 2012). The largest organ of human body is skin that acts as a boundary between environment and organism. Skin is exposed to internal and external aging processes that leads to changes in physiological functions and appearance of skin.

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Durability and Strength Aspects of Cement Concrete  Using GGBFS and METAKOLIN

Durability and Strength Aspects of Cement Concrete Using GGBFS and METAKOLIN

type of the earth mineral kaolinite which when not arranged appropriately may make ecological risks the encompassing territory. These two materials are utilized in the solid business, are powerful in expanding the compressive quality, elasticity and improved sturdiness. Mineral admixtures, for instance, fly powder, rice husk soot, metakaolin, silica seethe, etc are even more commonly used in the improvement of concrete mixes. They upgrades the holding of concrte nd makes it financially savvy. These materials increase the whole deal execution through reduced permeability achieving improved durability. Extension of such materials has shown the redesigns in the quality and solidness properties. Ground granulated impact heater slag (GGBFS) which is an outcome in the generation of iron in steel industry and ordinary waste Metakaolin which is a DE hydroxylated kind of the earth mineral kaolinite which when not masterminded fittingly may make natural dangers the including an area. These two materials are used in the strong business, are ground-breaking in extending the compressive quality, flexibility and improved solidness.

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