Thermoplastics can be used for various applications, which range from household articles to the aeronautic sector. This book, "Thermoplastic Elastomers", is comprised of nineteen chapters, written by specialized scientists dealing with physical and/or chemical modifications of thermoplastics and thermoplastic starch. Such studies will provide a great benefit to specialists in food, electric, telecommunication devices, and plastic industries. Each chapter provides a comprehensive introduction to a specific topic, with a survey of developments to date....
A scaffold provides a three-dimensional framework to support the tissue or organ-specific cells. The scaffold not only provides mechanical support, but it must also supply critical nutrients and transport metabolites to and from the developing tissue. Important scaffold properties vary depending on the tissue but typically include specific biomechanical properties, porosity, biocompatibility, and appropriate surface characteristics for cell adhesion and differentiation.
Scaffolds can be natural materials or synthetic polymers and are typically biodegradable.
Polyethylene-starch blend polymer has already found to be a potential candidate to replace non-degradable plastic in packaging . However, the degradation of that polymer in natural ambience (soil burial test) needs to be further evaluated. The purpose of this study is to investigate the degradability of PE-starch blend polymer in soil and in liquid medium. The soil is added starch degrading bacteria isolated from natural soil.
Chemical precipitation and complexation are primarily important for the inorganic species.
The formation of coordination complexes is typical behaviour of transition metals, which
provide the cation or central atom. Ligands include common inorganic anions such as Cl
as well as organic molecules such as amino acids. Such
complexation may facilitate the transport of metals.
Biodegradation is a reaction process mediated by microbial activity (a biotic reaction).
An additional benefit of hydrogen peroxide and Fenton's Reagent is the
temporary increase of oxygen levels in and around the treatment area. The
increased oxygen levels at the fringes of the treatment area can enhance naturally
occurring aerobic biodegradation processes that reduce contaminant mass. While
there may be concerns about oxidizing hydrocarbon-degrading bacteria in the
chemical oxidation treatment area, many studies have shown that soil cannot be
readily sterilized by Fenton's Reagent and that microbial populations rapidly
rebound following chemical oxidation treatment.
Remedial strategies for petroleum UST sites that include a combination of
active source zone treatment with enhanced natural attenuation outside the
contaminant plume core may consider chemical oxidation technologies. Many
chemical oxidation techniques also provide residual dissolved oxygen that is used
by aerobic microorganisms to biodegrade contaminants. In addition, these
technologies may also oxidize reduced electron acceptors (e.g., nitrogen to nitrate,
sulfides to sulfate), which are then used by anaerobic microorganisms to
Care should be taken in choosing preservatives. For example, Method 5035 notes
that, “Soil samples that contain carbonate minerals (either from natural sources or
applied as an amendment) may effervesce upon contact with the acidic preservative
solution in the low concentration sample vial.” Therefore, calcareous soils that
effervesce on contact with the preservative solution, which is intended for low-level
samples, should be preserved using an alternative technique.
In this communication, we report the synthesis of chitosan (CS, a biodegradable and biocom- patible natural polymer)  nanoparticles as drug carriers by ionic gelation. The method is based on ionic interactions between positively charged groups NH3 + of CS (in dilute CH3COOH solution) and negatively charged of sodium tripolyphos- phate, TPP).