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To extend the reuse method and rate of straw biomass, this paper investigated the effect of lignin synthetic phenolic resin (LPF) on the rheological properties of asphalt binder.

Four LPFs with 25%, 50%, 75% and 100% substitution rates were prepared by replacing phenol with lignin in synthetic resins and using it as a modifier to prepare a bio-asphalt binder. Temperature sweep tests were conducted to evaluate aging resistance and temperature sensitivity of the bio-asphalt binder. The rutting resistance of the bio-asphalt binder was evaluated by frequency sweeps and multiple stress creep recovery (MSCR) test. Linear amplitude sweep (LAS) tests were conducted to evaluate the fatigue resistance of the bio-asphalt binder. A master curve was constructed to further analyze the rheological properties of the bio-asphalt binder at different frequencies. The low-temperature cracking resistance of the binder was evaluated by G-R parameters, critical temperatures and ΔTc. Fourier transform infrared spectroscopy (FTIR) was performed to investigate the changes in the functional groups of the binder before and after aging.

The results indicated that adding LPF could improve the high-temperature rutting resistance, fatigue resistance, aging resistance of asphalt and the binders are less affected by temperature. Additionally, LPF slightly prohibited the low-temperature performance of the asphalt binder, which, however, was significantly lower than the base asphalt degradation during aging. Compared with base asphalt binders, the bio-asphalt binder showed no new absorption peaks generated after adding LPF, identifying that the improved asphalt binder performance by LPF was a mainly physical modification.

The main objective of this paper is to further improve the substitution rate (i.e. the mass substitution ratio of lignin to phenol) of lignin and broaden the application of biomass resins, thus realizing resource sustainability.

Influenced by postmodern and poststructuralist perspectives, cultural studies and humanities researchers have critiqued ways that old age plays out in lived realities – including effects of ageism and power loss in both private and public spheres. Generally, older people are perceived negatively and as less powerful than younger people. Age tends to trump most other social identity dimensions in negative ways so that aging is an eventuality that many people the world over dread or fear.

In recent years, age has been treated as a social, political and economic issue that draws from anxiety and fear associated with the advancing life course. Some nations outlaw age discrimination in the workplace, but others do not. So, while improved sanitation, diet and health care means that many people live longer, they still face enduring negative stereotypes about aging processes. Chapter 8 sharpens the focus on social identity marked by age and dimensions that overlap with age – in the larger social milieu and in organizational contexts. Several theoretical ties bind this chapter’s exploration of age and aging, including critical/cultural studies, feminism, critical gerontology, and postmodern and poststructuralist perspectives. To explore research on aging and identity, this chapter is divided into subthemes: sociocultural perspectives on and theorizing about aging, age categories and birth cohorts, aging effects for organizations, aging effects for employees, and age with other social identity intersectionalities.

This study aims to evaluate the effect of thermal aging temperature on the properties of Cu/Cu joints.

A new method that 1 um Zn-particles and Sn-0.3Ag-0.7Cu (SAC0307) with a particle size of 25–38 µm were mixed to fill the joint and successfully achieved the micro-joining of Cu/Cu under ultrasonic-assisted at low-temperature, and then the effect of thermal aging temperature on the properties of Cu/Cu joints was researched.

The composition of the intermetallic compounds (IMCs) on the upper and lower interfaces of Cu/SACZ/Cu joints remained unchanged, which was Cu₅Zn₈ in aging process, and the thickness of the IMCs on the upper and lower interfaces of the Cu/SACZ/Cu joints increased accordingly. Compared with the as-received joints, the thickness of the upper and lower interfaces IMCs of the soldering aged time for 24 h increased by 404.7% and 505.5% at 150ºC, respectively. The IMCs formation tendency and the IMCs growth rate of the lower interface are larger than those of the upper interface because the soldering seam near the IMCs at the upper and lower interfaces of the as-received joints were mostly white SAC0307 balls black Zn-particles, respectively. The growth activation energy of IMCs in the upper and lower interfaces is about 89.21 and 55.11 kJ/mol, respectively. Under the same aging time, with the increase of the aging temperature, the shear strength of Cu/SACZ/Cu joints did not change significantly at first before 150ºC. When the aging temperature reached 150ºC, the shear strength of the joints decreased significantly; the shear strength of the joints was the smallest at 150ºC for 24 h, which was 39.4% lower than that of the as-received joints because the oxidation degree of Zn particles in the joint with the increase of aging temperature and time.

Cu/Cu joints were successfully achieved under ultrasonic-assisted at low-temperature.

Aging workers are a diverse group yet research on aging infrequently examines the joint effects of age and gender upon various life domains and decisions. In order to fully understand the experience of a person, you must examine her/his roles and identities as they intersect. Intersectionality extends to the work setting, and the notion of intersectionality is presented as a paradigm that can yield significant insights into the joint consideration of age and gender in the workplace. These relationships have the potential to shape identities, which may in turn influence work perceptions and outcomes. As a result there are important considerations, consequences, solutions, and future research topics, as well as Human Resource practices that are discussed in this chapter.

This paper aims to investigate the transformations during aging at 200°C for different periods on microstructure and mechanical properties of high-temperature Zn-4Al-3Mg solders.

The solder was melted in a resistance furnace, and different cooling rates were obtained by changing the cooling medium. Subsequently, all the specimens were aged at 200°C for 20 h and 50 h. A scanning electron microscope equipped with an energy dispersive X-ray detector and X-ray diffraction were used for the observation of microstructures and the determination of phase composition. Tensile tests and Rockwell hardness tests were also performed.

After aging, Zn atoms precipitated from the supersaturated α-Al and the (α-Al + η-Zn)_eutectoid phase with the original fine lamellar structure coarsened and spheroidized to minimize the system energy. Among these solders, the furnace-cooled alloys exhibited the highest thermal stability, largely retaining their original morphology after aging, whereas the collapse and spheroidization of the η-Zn phase and the coarsening of the η-Zn dendrites took place in the air-cooled and water-cooled samples, respectively. Furthermore, a decrease in tensile strength during aging was attributed to the thermal softening effect. The variation of macro-hardness was mainly associated with the microstructural alterations in terms of quantity, morphology and distribution of soft η-Zn phase and hard intermetallic compounds induced by the aging treatment.

The structural stability of eutectic Zn-4Al-3Mg solders solidified at different cooling rates and the effect of aging on mechanical properties were investigated.

The purpose of this paper is to re‐examine the effect of population ageing on private saving, taking into account the fact that ageing is brought about by not only rising old‐aged dependency but also expanding longevity.

The study uses panel data of 22 OECD countries from 1961 to 2010. Linear and non‐linear panel regression methods are used. The study takes into account the time series characteristic of the data, such as the deterministic trend present in old‐age dependency ratio.

Longevity consistently has a significant positive impact on savings, while old‐aged dependency rate has no discernible impact once country‐specific time trends in the data are accounted for. The general finding within the literature where old‐age dependency exerts a negative impact on savings is sensitive to the manner in which the data is handled and/or the sample selected.

First, the authors jointly consider rising old‐aged dependency and expanding longevity on savings, thus avoiding potential omitted variable bias in previous studies. Second, they explore non‐linearity in the savings‐ageing relationship which was ignored previously. Third, they identify whether saving rate and demographic measures are sharing common stochastic trends or driven by individual deterministic trends to avoid spurious regression results.

The purpose of this paper is to analyze the extent of aging in the agricultural labor force and its effect on farm production in a province of China.

The analysis uses panel data for the years 2004 through 2008 from a representative sample of farm households in Liaoning province. Descriptive statistics reveal the age structure of the agricultural labor force and correlations between labor force age and production characteristics. A translog stochastic frontier production function and technical inefficiency model is employed to analyze the effect of aging of the labor force on the technical efficiency of crop production.

The paper finds an accelerating trend towards aging of the agricultural labor force in the data. Results from the stochastic frontier production function and efficiency analysis reveal that household‐level technical efficiency increases until maximum efficiency is reached when the average age of the household labor force is 45, after which efficiency declines.

Aging of China's rural labor force may affect efficiency and productivity in crop production. Agricultural policies may need to pay more attention to the aging of the agricultural labor force. Some measures should be taken to address the pattern of migration, and policies to improve the social and economic environment in rural areas for younger workers should be developed. Also, extension programs could help older farmers to maintain efficient farming methods.

This is one of very few analyses of the effects of aging on production efficiency for a developing country, as well as for China. The analysis uses a unique panel dataset that covers 24 counties, 1,890 rural households, and more than 6,000 individuals, with each household tracked for five years. Most of the literature estimating technical efficiency carries out the analysis at the individual level; in China and other developing countries, farming is carried out at the household level. We have adapted the methodology to apply to situations where the unit of analysis is the household.

Human life course is shaped by a set of consecutive roles, such as being a worker, a spouse and a parent in a standard biography. However, being instantly disengaged from any of these roles may cause devastating effects on people’s lives. This discontinuity not only influences the very dynamics of the meaning of working, but also causes aging labor force to be excluded from the market economy. Experienced workers are drained from the pool of labor force just because they are old. This study aims at focusing on the effects of compulsory retirement both upon individual and upon structure, through the lenses of Political Economy of Aging (PEA) and Human Resources Management (HRM). The PEA perspective proposes a tripartite relationship among state (politics), market (economy) and individual (society), while HRM perspective provides an insight of an effective use of workforce from different generations, including older generation.