Upon contact with water, under a variety of conditions, C60 spontaneously forms a stable aggregate with nanoscale dimensions (d = 25-500 nm), termed here "nano-C60". The color, hydrophobicity, and reactivity of individual C60 are substantially altered in this aggregate form. Herein, we provide conclusive lines of evidence demonstrating that in solution these aggregates are crystalline in order ...

abstract this study aimed to investigate the effects of urban wastewater on some soil physical and chemical properties in segzi, east isfahan. six sites were selected considering the planted species (haloxylon persicum and nitraria schoberi) and irrigation types (control or no irrigation, water logged and furrow irrigation methods). the 4 to 12 replications were chosen in each site depending on...

We investigate the colloidal stability of gold nanoparticles (AuNPs) coated with zwitterionic sulfobetaine polymers in aqueous solution. Zwitterionic polymers with different molar masses, synthesized by reversible addition-fragmentation chain transfer (RAFT) polymerization of N,N'-dimethyl(methacrylamido propyl)ammonium propanesulfonate (SPP) exhibit a well known Upper Critical Solution Tempera...

Characteristics of produced concrete become changedthrough changingthe characteristics of materials constituting the concrete. These changes include: The quality of cement, the real ration of water to cement: with neglecting the further water within the aggregates or lack of that, the consideredratio fluctuates and the characteristics of the aggregate which are related to the following dimensio...

Soil particle interactions are strongly influenced by the concentration, valence and ion species and the pH of the bulk solution, which will also affect aggregate stability and particle transport. In this study, we investigated clay aggregate stability in the presence of different alkali ions (Li+, Na+, K+, and Cs+) at concentrations from10-5 to 10-1 mol L-1. Strong specific ion effects on clay...

the location of extracellular enzyme activities in soil aggregates can be influenced by slope position. this study aims to determine the effect of slope position on aggregate distribution of organic c and l-glutaminase activity. the soils were collected from different slope positions (shoulder, backslope, footslope and toeslope) at two pasture ecosystems (fereydoonshahr and chelgerd, central ir...

The effects of excipient crystallinity and water content on the physical stability of salmon calcitonin (sCT) in a spray-dried powder for inhalation have been investigated. sCT was dissolved in water with and without mannitol and then spray dried using a Büchi 190 spray dryer. The spray dried powders were stored for 5 days at 0, 29, 51, 58, 69, and 84% relative humidity at ambient temperature. ...

Although humanity depends on the continued, aggregate functioning of natural ecosystems, few studies have explored the impact of community structure on the stability of aggregate community properties. Here we derive the stability of the aggregate property of community biomass as a function of species' competition coefficients for a two-species model. The model predicts that the stability of com...