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Selection of a proper binder–aggregate combination is an important step to ensure optimum resistance to moisture-induced damage in asphalt mixes. In recent years, such selection has become more crucial as asphalt industries are using various additives and modifiers in asphalt mixes that can substantially change bonding strength of a binder–aggregate system. Also, environmental factors such as oxidative aging can affect the chemical compositions of the binder and influence moisture-induced damage resistance of a mix. In order to understand the mechanisms of moisture-induced damage, it is important to determine the chemical and thermodynamic properties of constituent materials of a mix and identify their contributions to the bond strength. The present study was undertaken to explore the effects of aggregate types, additives, and aging on the moisture susceptibility of asphalt mixes using chemical and thermodynamic approaches. For this purpose, a PG 64-22 and a PG 76-28 binder were blended with a warm mix asphalt (WMA) additive, an antistripping agent (ASA), a reclaimed asphalt pavement (RAP) binder and polyphosphoric acid (PPA). The surface free energy (SFE) components of these binder blends under unaged, short-term aged, and long-term aged conditions were determined using the dynamic Wilhelmy plate (DWP) method for measuring dynamic contact angle. Chemical analyses of the binder blends were carried out using x-ray fluorescence (XRF) analysis and Fourier transform infrared (FTIR) spectroscopy. Properties of five commonly available local aggregates were determined using XRF and universal sorption device (USD) testing. The SFE components of the binders and aggregates were used to quantify bonding characteristics of binder–aggregate systems under dry and wet conditions. Aggregate properties significantly influenced the moisture-induced damage potential of a mix. In addition, an increase in carbonyl and sulfoxide functional groups resulted in increased moisture susceptibility with aging. Therefore, the presence of amine functional groups in both WMA and ASA is expected to provide resistance to moisture-induced damage and conversely the presence of PPA may reduce resistance to moisture-induced damage of a binder–aggregate system. [ABSTRACT FROM AUTHOR]

Cotton fiber consumption is higher than any other natural fiber due to its superior mechanical and physical properties. In the conventional reactive dyeing process, the dye undergoes hydrolysis due to hydrogen bonding and weak Van der Waals forces, yielding poor washing color fastness. Additionally, the post-dyeing wash-off process consumes significant amounts of water, energy, and time in order to remove the unreacted and hydrolyzed dye. Therefore, reactive dyes are predominantly utilized to color cotton fabrics as the covalent bond formed between dye and fiber results in excellent washing fastness for a wide range of colors, and improved ease of use. To support more efficient, economical, and sustainable reactive dyeing, polymers can be used as effective dye transfer inhibitors (DTIs) in the reactive wash-off process. In this study, poly(vinylpyrrolidone) (PVP) homopolymer and poly(vinylpyrrolidone)-co-poly(vinylimidazole) (PVP-co-PVI) were synthesized at different molecular weights. These polymers were then employed as DTIs to evaluate their performance during the wash-off process for dyed cotton fabrics treated with three reactive dyes (Reactive Red 195, Reactive Blue 221, and Reactive Yellow 145). It is noteworthy to mention that the alternative wash-off procedure involved only three stages, in contrast to the series of washing steps necessary in the conventional method. Evaluation of the DTIs was focused on parameters such as color strength, washing fastness, chemical oxygen demand (COD), as well as energy, water, and time consumption. The findings revealed that while the polymer DTIs generated minor differences in dyed fabric colors in comparison to conventional dyeing, they significantly improved washing fastness. The polymer DTIs studied display excellent potential to provide a much more sustainable dyeing process by saving 90% energy, 40% water, and 50% time versus conventional wash-off processing. The wastewater COD values from the polymer-assisted reactive dye wash-off process were higher for all reactive dyes tested than those from conventional processing. While the higher COD values are attributed to the lower water volumes, this finding highlights the need for further studies. In summary, PVP polymers successfully served as DTIs in the reactive dyeing washing-off process, providing massive water-energy-time efficiency improvements and, subsequently, a more sustainable process for cotton fabric dyeing. [ABSTRACT FROM AUTHOR]

Vascular disease is the leading cause of death in populations suffering from advanced stages of chronic kidney disease (CKD). Cardiovascular calcification increases the risk of cardiac morbidity and mortality in sixty to eighty percent of dialysis patients with end-stage-renal-disease (ESRD). This paper will focus on developing a drug delivery system to de-mineralize calcified regions of the artery wall that cause arteriosclerosis in ESRD patients and provide preventative therapy to dialysis patients with early stages of CKD. We are proposing a targeted drug therapy to reverse vascular calcification in patients with ESRD. A pH responsive polymersome will be developed for intravenous administration to carry, and release Fetuin-A to sites of calcification by binding to matrix (Gla) proteins (MGPs) when blood pH drops below 7.4. Fetuin-A, an inhibitor of extra-skeletal calcification, is made to solubilize calcium-phosphate minerals. MGPs inhibit soft-tissue mineralization and are up-regulated when pH falls below 7.4. Recruited to sites of calcification MGPs accumulate in the calcified lesions. Surface receptors on the polymersome will bind to MGPs present in calcified regions causing the targeted release of the drug Fetuin-A. Our drug delivery system aims to improve the life expectancy of dialysis patients, especially non-transplant candidates and those on a transplant waiting list. Re-establishing physiological levels of Fetuin-A with targeted drug-delivery should reverse the pathological calcification in ESRD patients. In addition to providing a therapy for arteriosclerosis we aim to actively reduce the risk of cardiac morbidity and mortality associated with vascular calcification in dialysis patients with early stages of CKD. Keywords: vascular calcification, arteriosclerosis, end-stage-renal-disease, Fetuin-A, matrix Gla proteins, chronic kidney disease, polymersome, INTRODUCTION Cardiovascular disease (CVD) is the leading cause of mortality for patients at all stages of chronic kidney disease (CKD) [1]. Patients with CKD are more likely to die of [...]

The formation of dendrites is the bottleneck to harvest the high theoretical capacities of metal anodes. In this study, we investigated the impact of the solid‐electrolyte interface (SEI) layer on the electroplating of zinc metals in organic and aqueous electrolytes by using electrochemical techniques coupled with SEM, FTIR, and XPS. First, the electrochemical response of Zn plating in organic or aqueous electrolytes was compared with the ones for Li and Na metal plating by using analogous perchlorate salt dissolved in the same organic solvent. Under similar charge conditions, the cycle life of the metal electrodes was longer in the order of Zn (aqueous)>Li>Zn (organic)>Na. In organic electrolytes, the cycle life of the PAO‐Zinc is almost three‐fold longer than the as‐received zinc electrodes. The methodology established here can be used to study the impact of electrolyte salt and additives on the formation of dendrites on metal electrodes. [ABSTRACT FROM AUTHOR]

ABSTRACT Self-assembly and mechanical properties of triblock copolymers in a mid-block selective solvent are of interest in many applications. Herein, we report physical assembly of an ABA triblock copolymer, [PMMA-P nBA-PMMA] in two different mid-block selective solvents, n-butanol and 2-ethyl-1-hexanol. Gel formation resulting from end-block associations and the corresponding changes in mechanical properties have been investigated over a temperature range of −80 °C to 60 °C, from near the solvent melting points to above the gelation temperature. Shear-rheometry, thermal analysis, and small-angle neutron scattering data reveal formation and transition of structure in these systems from a liquid state to a gel state to a percolated cluster network with decrease in temperature. The aggregated PMMA end-blocks display a glass transition temperature. Our results provide new understanding into the structural changes of a self-assembled triblock copolymer gel over a large length scale and wide temperature range. © 2017 Wiley Periodicals, Inc. J. Polym. Sci., Part B: Polym. Phys. 2017, 55, 877-887 [ABSTRACT FROM AUTHOR]