Copolymers of (2-hydroxyethyl methacrylate) (HEMA) and methacrylamide monomers conjugated with amino acids were synthesized and crosslinked with ethylene glycol dimethacrylate. The resulting library of copolymers was mineralized in vitro using two distinct methods. In the first mineralization method, the copolymers were polymerized in the presence of a sub-micron hydroxyapatite (HA) suspension....

Block urea/urethane co-polymer films present elastomeric properties with the possible tuning of their surface properties within a wide range and are therefore considered relevant surfaces for possible medical applications. In particular, thin free standing films of urea/urethane elastomers with two soft segments, polypropylene oxide and more hydrophobic polybutadiene, develop multistable states...

Nitrogen fertilization is essential for optimizing crop yields and economic returns in irrigated cropping systems in the Central Great Plains area of the USA. However, N application generally increases the emissions of the potent greenhouse gas, N 2 O, from these systems. Nitrous oxide is produced through nitrifi cation and denitrifi cation processes in the soil. Agriculture contributes approxi...

The coagulation properties of cellulose-NaOH/thiourea/urea/H2O solutions under various coagulation conditions have been investigated, to determine the kinetics of this special coagulation process (known as including diffusion on the contact surfaces of the polymer solution with the precipitant and the chemical reaction between acid and alkali). The observation was made that, at the beginning of...

the nutritional value of cereal straw can be increased using urea treatments as a source of ammonia. the conventional urea treatment process for cereal straw is a laborious and time-consuming task. it is essential to facilitate or eliminate part of the procedure with the use of machinery. this study examines the mechanical urea treatment of wheat straw and compares chemical components and diges...

Water and nitrogen availability plays an important role in the biogeochemical cycles of essential elements, such as carbon (C), nitrogen (N) and phosphorus (P), in agricultural ecosystems. In this study, we investigated the seasonal changes of C, N and P concentrations, accumulation, partitioning, and C:N:P stoichiometric ratios in different plant tissues (root, stem-leaf, and panicle) of late-...

in order to increase grain yield, nitrogen use efficiency (nue) and nitrogen apparent recovery fraction (narf) in wheat (triticum aestivum l.), this experiment was carried out with 5 or 6 treatments and 3 or 4 replications in 14 locations at 22 different sites in iran during the 2004-05 growing season. the experiment was designed as a completely randomized block. the effect of n sources and tim...

objective: pmbn, poly [2-methacryloyloxyethyl phosphoryl choline (mpc)-co-n- buthyl methacrylate (bma)-co-p-nitrophenyl- oxycrabonyl poly (ethylene glycol-methacrylate (meonp)], as a biocompatible ter-polymer is a unique polymer with wide range of application from drug delivery systems to scaffolds and biomedical devices. in this research, monomer of p- nitrophenyl- oxycarbonyl poly (ethylene g...

Optimizing the timing of nitrogen (N) enhanced efficiency fertilizers (EEFs) may maximize winter wheat ( Triticum aestivum L.) grain yield, protein content, and N-use (NUE). From 2013 to 2018, experiments were conducted at two irrigated six rain-fed sites across Canadian Prairies (24 site-years) evaluate responses N source timing/placement effects EEFs. Nitrogen sources included untreated urea,...