Polymers
Mostrando 1-12 de 2047 artigos, teses e dissertações.
-
1. A review on the ceramic additive manufacturing technologies and availability of equipment and materials
Abstract Ceramic additive manufacturing allows the fabrication of small series of complex parts without the high costs of molds usually associated with traditional ceramic processing. Although research into ceramic 3D printing by all technologies started back in the 90s, its industrial application is still quite restricted when compared to polymers and metal
Cerâmica. Publicado em: 2022
-
2. Preparation of Silicon Oxycarbide (SiCO) Ceramics from Different Polymer Architectures and Assessment on the Performance as Electrodic Materials for Voltammetric Sensing of Antioxidant Phenolic Compounds
Silicon oxycarbide (SiCO) ceramics obtained from polymer pyrolysis and with varied carbon contents were prepared and evaluated as new electrodic materials for sensing of tert butylhydroquinone (TBHQ) and butylated hydroxyanisole (BHA) antioxidants. Three polymers were synthesized varying molecular architecture and aromatic carbon groups, followed by pyrolysi
Journal of the Brazilian Chemical Society. Publicado em: 2022
-
3. Easily applicable protocol to formulate inks for extrusion-based 3D printing
Abstract 3D printing is a disruptive technology that is a key driver of the new industrial revolution. Among the various 3D printing methods, direct-ink-writing (DIW) takes a viscous ink material, extrudes it through a nozzle, and deposits it layer-by-layer to create 3D objects. DIW is a versatile method that can print ceramics, polymers, metals, living cell
Cerâmica. Publicado em: 2022
-
4. FEATURES AND STRATEGIES FOR SCAFFOLD DESIGN AND PRODUCTION FOR TISSUE ENGINEERING
Failure or loss of human tissues and organs due to illness or injury requires the partial or even total transplantation. Although transplantation is a successful intervention, donor availability and immune rejections represent still the main drawbacks. In addition, the fast and proper recovery of the patient is nowadays more than necessary to prevent infecti
Química Nova. Publicado em: 2022
-
5. Chemometric Evaluation of Poly(3-hexylthiophene) Electrochemical Aging Path as a Function of Electrochemical Synthesis Variables
Conductive polymers are versatile materials that can be applied in many different technology fields, especially green energy. They have several advantages, such as easy synthesis, low density, and cost. However, its electric conduction property is also related to material aging with great loss of their characteristics, limiting their applicability. The in-de
Journal of the Brazilian Chemical Society. Publicado em: 2022
-
6. What is new in non-chromatographic flavonoid purification?
Flavonoids are metabolites occurring in all plant tissues and present different biological activities. They occur in a mixture of similar polarity with laborious separation and purification processes, usually furnishing low yields. Semi-preparative chromatographic methods are universally employed procedures for their isolation. This paper discusses the state
Química Nova. Publicado em: 2022
-
7. Characterization and mechanical properties of one-part geopolymer based on a pure metakaolin
Abstract Geopolymers are amorphous silicate polymers that have been extensively studied due to their applications, scientific and technical relevance, and their potential as cement in substitution to Portland. Much of the focus has been in the use of precursors and aggregates that are rarely pure and homogeneous with the use of tailings being very common. Th
REM - International Engineering Journal. Publicado em: 2022
-
8. Polyacrylamides in reverse cationic iron ore flotation: bench scale study
Abstract A bench scale study was carried out to investigate the influence of polyacrylamides as co-depressant in a blend with starch depressant on the reverse cationic iron ore flotation. The results indicated that the use of polyacrylamides as dual function polymer should be an alternative to improve the flotation process. These polymers act as a depressant
REM, Int. Eng. J.. Publicado em: 2021-09
-
9. Polyacrylamides as co-depressant in hematite and quartz microflotation
Abstract In the present study, microflotation experiments were performed on pure minerals systems involving hematite and quartz in the presence of etherdiamine as collector. The influence of polyacrylamides as co-depressant was investigated in a blend with starch depressant. The results obtained demonstrated that all the polyacrylamides used were efficient i
REM, Int. Eng. J.. Publicado em: 2021-09
-
10. PREPARATION OF HYBRID POLYMERS AND USE AS CONTROLLED RELEASE DELIVERY VEHICLE FOR VOLATILE REPELLENT TO CONTROL Aedes aegypti
The Zika virus is a flavivirus spread by the Aedes aegypti mosquito, which also transmits dengue and chikungunya. Current forms of control include elimination of mosquito breeding sites, use of insecticides, repellents and other means. The present study developed new adsorbent materials based on silica and biomaterials capable of releasing an Aedes aegypti m
Quím. Nova. Publicado em: 2021-04
-
11. IMIDAZOL E CATÁLISE: UM PAR PERFEITO
The imidazole (IMZ) ring presents several chemical properties that turns it into a versatile acid-basic/nucleophilic catalyst. The discovery of the biological properties of histidine (amino acid with IMZ ring) instigates the study of this class of compounds. It is found in nature in several enzymes such as chymotrypsin and RNAses due to these properties. Thi
Quím. Nova. Publicado em: 2021-03
-
12. Method for Cleaning Back-Produced Water from Polymer Flooding Operations to Determine Polymer Molar Mass Using Size-Exclusion Chromatography
One of the methods used by the oil industry to increase production is to inject water, containing polymer, into the reservoir. The viscosity of the aqueous solution is primarily responsible for the efficiency of this method, and is achieved using polymers with high molar mass. However, polymer degradation can occur during pumping and fluid displacement in th
J. Braz. Chem. Soc.. Publicado em: 2020-12