•The epoxy asphalt have the potential to recycle a mixture with 100% RAP content.•The rutting resistance of recycled mixture was excellent.•The cracking resistance of recycled mixture is close to the ...virgin epoxy mixture.•The moisture susceptibility is as excellent as the virgin epoxy mixture.•The fatigue resistance of recycled mixture is inferior to the virgin epoxy mixture.
With the rising cost of pavement materials and increasingly stringent environmental protection and sustainability policies, asphalt recycling technology with high reclaimed asphalt pavement (RAP) content is becoming more essential. This study was designed to explore the feasibility of using epoxy asphalt for the recycling of mixture containing 100% RAP. The performance of the epoxy asphalt recycled mixture and the virgin epoxy asphalt mixture was evaluated and compared. The wheel tracking test and trabecular bending test were carried out to evaluate the high and low-temperature performance. The trabecular fatigue test was adopted to measure fatigue resistance. The indirect tensile test and the semi-circular bending test were carried out to evaluate the moisture susceptibility of the epoxy asphalt recycled mixture. The rutting resistance of epoxy asphalt recycled mixture was found much better than the virgin epoxy asphalt mixture. The low temperature cracking resistance and moisture susceptibility of epoxy asphalt recycled mixture was close to the virgin epoxy asphalt mixture. The influence of epoxy resin components on cracking resistance was more obvious than that of aged asphalt binder. However, the fatigue performance of epoxy asphalt recycled mixture was inferior to the virgin epoxy asphalt mixture. Based on the performance comparison, the epoxy asphalt have the potential to recycle a mixture with 100% RAP content.
I Am Hip-Hop Rausch, Andrew J
2011, 2011-04-01
eBook
Author Andrew J. Rausch interviewed 24 individuals whose creative expressions are intimately associated with the world of hip-hop music and culture. Those interviewed include emcees, DJs, producers, ...graffiti artists, poets, and journalists. Topics of these conversations cover the careers of each of these people and their contributions/affiliations with hip-hop, as well as their views on different trends within the music.
Accurate characterisation of reclaimed asphalt pavement (RAP) binder is an important prerequisite to successfully use RAP in new pavements. The conventional characterisation method is performed on ...the extracted and recovered RAP binders using harmful chemical solvents. A previous study proposed an enhanced mortar testing method that eliminates the use of chemical solvent by establishing a relationship between binder and mortar properties. As a follow-up, the objective of this study was to examine whether the enhanced mortar method is applicable at both high and low temperatures. The enhanced mortar method was evaluated using six RAP sources with distinct binder characteristics by comparing high and low temperature true grades measured from recovered RAP binders. Satisfactory results substantiate that the mortar methods can be used as an alternative to the solvent method, which lays a solid foundation for pursuing environmental and economic benefits associated with proper RAP usage.
In the 1990s, Los Angeles was home to numerous radical social and environmental eruptions. In the face of several major earthquakes and floods, riots and economic insecurity, police brutality and ...mass incarceration, some young black Angelenos turned to holy hip hop—a movement merging Christianity and hip hop culture—to “save” themselves and the city. Converting street corners to open-air churches and gangsta rap beats into anthems of praise, holy hip hoppers used gospel rap to navigate complicated social and spiritual realities and to transform the Southland’s fractured terrains into musical Zions. Armed with beats, rhymes, and bibles, they journeyed through black Lutheran congregations, prison ministries, African churches, reggae dancehalls, hip hop clubs, Nation of Islam meetings, and Black Lives Matter marches. Zanfagna’s fascinating ethnography provides a contemporary and unique view of black LA, offering a much-needed perspective on how music and religion intertwine in people’s everyday experiences.
•A systematic method for the comprehensive utilization of RAP is proposed, the separated aggregate can be reused for road construction.•Porous structure and C-O groups are formed after the ...oxygen-enriched waste asphalt carbonization.•The waste asphalt derived carbon exhibits a specific capacity of 645.1 mAh/g at 0.1 A/g current density, while the capacity remains 96.8% after 800 cycles at 0.2 A/g.•The effects of C-O structure formed after oxygen incorporation were investigated by DFT calculation.
The current recycling efficiency of recycled asphalt pavement (RAP) remains low, leading to significant non-renewable resource wastage. Herein, we proposed a method for utilizing RAP based on the aging characteristics of waste asphalt, which separates RAP into two parts: waste asphalt and aggregate. The separated aggregate can be reused for road construction, and the separated asphalt is converted into the negative electrode material of lithium-ion battery after oxygen enrichment treatment and carbonization. In the process of carbonization, the waste asphalt formed a three-dimensional porous carbon structure and C-O configuration suitable for lithium storage under the effect of oxygen elements. This carbon material exhibits a specific capacity of ∼ 645 mAh g–1 at 0.1 A g–1 current density, while the capacity remains ∼ 97 % after 800 cycles at 0.2 A g–1. The DFT calculation results demonstrate the enhanced adsorption of Li-ion near the C-O configuration, which further proves the beneficial effect of oxygen incorporation. By efficiently separating aggregate from waste asphalt, this study explores favorable conditions for waste asphalt utilization, enhances RAP reuse efficiency, and provides dual benefits in terms of energy conservation and environmental protection.
A single microRNA (miRNA) can regulate expression of multiple proteins, and expression of an individual protein may be controlled by numerous miRNAs. This regulatory pattern strongly suggests that ...synergistic effects of miRNAs play critical roles in regulating biological processes. miR-9 and miR-124, two of the most abundant miRNAs in the mammalian nervous system, have important functions in neuronal development. In this study, we identified the small GTP-binding protein Rap2a as a common target of both miR-9 and miR-124. miR-9 and miR-124 together, but neither miRNA alone, strongly suppressed Rap2a, thereby promoting neuronal differentiation of neural stem cells (NSCs) and dendritic branching of differentiated neurons. Rap2a also diminished the dendritic complexity of mature neurons by decreasing the levels of pAKT and pGSK3β. Our results reveal a novel pathway in which miR-9 and miR-124 synergistically repress expression of Rap2a to sustain homeostatic dendritic complexity during neuronal development and maturation.
The origin story of hip-hop-one that involves Kool Herc DJing a house party on Sedgwick Avenue in the Bronx-has become received wisdom. But Joseph C. Ewoodzie Jr. argues that the full story remains ...to be told. In vibrant prose, he combines never-before-used archival material with searching questions about the symbolic boundaries that have divided our understanding of the music. InBreak Beats in the Bronx, Ewoodzie portrays the creative process that brought about what we now know as hip-hop and shows that the art form was a result of serendipitous events, accidents, calculated successes, and failures that, almost magically, came together. In doing so, he questions the unexamined assumptions about hip-hop's beginnings, including why there are just four traditional elements-DJing, MCing, breaking, and graffiti writing-and not others, why the South Bronx and not any other borough or city is considered the cradle of the form, and which artists besides Kool Herc, Afrika Bambaataa, and Grandmaster Flash founded the genre. Ewoodzie answers these and many other questions about hip-hop's beginnings. Unearthing new evidence, he shows what occurred during the crucial but surprisingly underexamined years between 1975 and 1979 and argues that it was during this period that the internal logic and conventions of the scene were formed.
The environmental risks associated with the storage, reuse, and disposal of unencapsulated reclaimed asphalt pavement (RAP) has been previously examined, but because of a lack of standardized column ...testing protocols and recent interest on emerging constituents with higher toxicity, questions surrounding leaching risks from RAP continue. To address these concerns, RAP from six, discrete stockpiles in Florida was collected and leach tested following the most up-to-date, standard column leaching protocol – United States Environmental Protection Agency (US EPA) Leaching Environmental Assessment Framework (LEAF) Method 1314. Sixteen EPA priority polycyclic aromatic hydrocarbons (PAHs), 23 emerging PAHs, identified through relevance in literature, and heavy metals were investigated. Column testing showed minimal leaching of PAHs; only eight compounds, three priority PAHs and five emerging PAHs, were released at quantifiable concentrations, and where applicable, were below US EPA Regional Screening Levels (RSL). Though emerging PAHs were identified more frequently, in most cases, priority compounds dominated contributions to overall PAH concentration and benzo(a)pyrene (BaP) equivalent toxicity. Except for arsenic, molybdenum, and vanadium in two samples, metals were found below limits of detection (LOD) or below risk thresholds. Arsenic and molybdenum concentrations diminished over time with increased exposure to liquid, but elevated vanadium concentrations persisted in one sample. Further batch testing linked vanadium to the aggregate component of the sample, unlikely to be encountered in typical RAP sources. As demonstrated by generally low constituent mobility observed during testing, the leaching risks associated with the beneficial reuse of RAP are limited, and under typical reuse conditions, factors of dilution and attenuation would likely reduce leached concentrations below relevant risk-based thresholds at a point of compliance. When considering emerging PAHs with higher toxicities, analyses indicated minimal impact to overall leachate toxicity, further suggesting that with proper management, this heavily recycled waste stream is unlikely to pose leaching risk.
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•Analysis of constituent mobility from RAP via representative column leach testing.•Twenty-three emerging PAH, sixteen priority PAH, and trace metals are investigated.•All PAH and most metal concentrations in leachate fall below risk-based thresholds.•PAH concentration and toxicity is predominantly contributed by priority compounds.
The more reclaimed asphalt pavement (RAP) is used in asphalt production, the more properties of the pavement depend on the characteristics of the RAP. Crushing and sieving of RAP into different ...fractions are the most used means of RAP processing that can allow ensuring consistency and the desired properties of the produced mixture. Currently, however, there is no method to compare different RAP processing methods. Here we propose three indexes to evaluate crushing and screening of RAP - Chunk index, Breakdown index, and Filler increase index (CBF indexes). These indexes are derived from the black and white grading curves of RAP and, therefore, can be of practical use for asphalt producers. Through full-scale validation with four different crushers, we found that the indexes allow for a quantitative comparison of different RAP processing methods and can be used to optimise the configuration of a particular crusher. A calculation tool is attached to the paper.
2007 Alan Merriam Prize presented by the Society for Ethnomusicology
2007 PEN/Beyond Margins Book Award Finalist
When we think of African American popular music, our first thought is probably not of ...double-dutch: girls bouncing between two twirling ropes, keeping time to the tick-tat under their toes. But this book argues that the games black girls play —handclapping songs, cheers, and double-dutch jump rope—both reflect and inspire the principles of black popular musicmaking.
The Games Black Girls Play illustrates how black musical styles are incorporated into the earliest games African American girls learn—how, in effect, these games contain the DNA of black music. Drawing on interviews, recordings of handclapping games and cheers, and her own observation and memories of gameplaying, Kyra D. Gaunt argues that black girls' games are connected to long traditions of African and African American musicmaking, and that they teach vital musical and social lessons that are carried into adulthood. In this celebration of playground poetry and childhood choreography, she uncovers the surprisingly rich contributions of girls’ play to black popular culture.
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