Nanocrystals
Mostrando 1-12 de 104 artigos, teses e dissertações.
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1. Improving Photoluminescence Quantum Yield of CdTe Quantum Dots Using a Binary Solvent (Water + Glycerin) in the One-Pot Approach Synthesis
The present work describes the comparison of the optical and structural properties between CdTe quantum dots (QD) synthesized in water and in the binary solvent (water + glycerin) via one-pot approach synthesis. The optical properties of the nanocrystals obtained with different synthesis parameters were characterized by UV-visible and photoluminescence spect
J. Braz. Chem. Soc.. Publicado em: 2021-04
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2. NANOCRISTAIS DE PEROVSKITAS COLOIDAIS: HISTÓRICO, PROPRIEDADES E APLICAÇÕES
Recently, a new class of materials, the Perovskite Nanocrystals, also known as perovskite quantum dots (PQDs) has emerged. Perovskite nanocrystals are promising in optoelectronics due to their quantum confinement properties, narrow photoluminescence bands with short decay times, optically tunable bandgaps, easy surface passivation and high photoluminescent q
Quím. Nova. Publicado em: 2020-09
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3. Immunophenotyping, plasticity tests and nanotagging of stem cells derived from adipose tissue of wild rodent agouti (Dasyprocta prymnolopha)
RESUMO Há um interesse crescente no estudo das células estaminais mesenquimais, não especializadas, pois ainda existem algumas discussões sobre seu comportamento in vitro. A medicina regenerativa é uma ciência em fase de crescimento que desenvolve tratamentos como terapia celular utilizando células estaminais somáticas. Em vários estudos, o tecido a
Arq. Bras. Med. Vet. Zootec.. Publicado em: 28/10/2019
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4. Effects of Heat Treatment and Yb 3+ Concentration on the Downconversion Emission of Er 3+ /Yb 3+ Co-Doped Transparent Silicate Glass-Ceramics
The SiO2-Al2O3-BaF2-TiO2-CaF2 transparent silicate glass-ceramics containing BaF2 nanocrystals were successfully prepared by heat treatment process through conventional melting method. Effects of heat treatment processes and Yb3+ concentration on the downconversion (DC) emission of the co-doped Er3+/Yb3+ transparent silicate glass-ceramics were investigated.
Mat. Res.. Publicado em: 28/10/2019
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5. (Bio)conjugation Strategies Applied to Fluorescent Semiconductor Quantum Dots
Quantum dots (QDs) are semiconductor nanocrystals, which present unique photophysical properties, enabling their application as new fluorescent platforms for biomedical sciences. Colloidal QDs are end-capped with organic or inorganic compounds, not only to prevent their agglomeration but also to provide reaction sites for the attachment of targeting (bio)mol
J. Braz. Chem. Soc.. Publicado em: 24/10/2019
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6. Modification of the Crystalline Structure of ZnO Nanoparticles Embedded Within a SiO2 Matrix due to Thermal Stress Effects
Self-assembled nanocrystals of ZnO were embedded within a SiO2 matrix by a sequential deposit using reactive R.F. sputtering. The ZnO nanoparticles (NP’s) were obtained by depositing a very thin layer (~20 nm) of Zn on the bottom of the valleys of a first SiO2 rough surface and then covered by another SiO2 layer at 500 ºC. The stress produced, due to the
Mat. Res.. Publicado em: 23/09/2019
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7. THE EFFECT OF CELLULOSE NANOCRYSTALS IN SUGARCANE BAGASSE PARTICLEBOARDS OF PITH AND FIBERS
ABSTRACT The aim of this research was to investigate sugarcane bagasse (SCB) particleboards, using two kinds of particles, from pith and fibers, reinforced with cellulose nanocrystals (NCC). The NCCs were dispersed in the adhesive urea formaldehyde (UF) using a sonificator in two proportions (0 and 1%). The NCCs and UF were applied in the SCB particles using
CERNE. Publicado em: 09/09/2019
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8. Cellulose Nanocrystals and Jute Fiber-reinforced Natural Rubber Composites: Cure Characteristics and Mechanical Properties
A comparative study was conducted for three natural rubber (NR) composites: one containing raw jute fibers, one containing bleached jute fibers, and one containing cellulose nanocrystals (CNCs). The composites were prepared by adding each filler at 5 or 10 phr to the latex before chemical coagulation, and the composites were processed in a two-roll mixing mi
Mat. Res.. Publicado em: 26/08/2019
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9. Semiconductor Nanocrystals-Reduced Graphene Composites for the Electrochemical Detection of Carbendazim
A new nanocomposite based on ZnCdTe semiconductor nanocrystals (NCs) synthesized in situ on reduced graphene oxide (rGO) was obtained. The heterostructure was characterized using UV-Vis emission and absorption spectroscopies, which provided evidences of the growth of the nanocrystals onto the rGO matrix. To evaluate the electrochemical performance, carbon pa
J. Braz. Chem. Soc.. Publicado em: 23/05/2019
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10. Synthesis of Hydrotalcite-Supported CdTe Semiconductor Nanocrystals for Electrochemical Detection of Ciprofloxacin
In this work, CdTe quantum dots (QDs) were controllably grown onto the surface of layered double hydroxide (LDH) aiming to develop a sensitive and selective method for the electrochemical detection of ciprofloxacin (CPX). Emission and absorption spectroscopy results as well as high-resolution transmission electron microscopy (HRTEM) images evidenced the form
J. Braz. Chem. Soc.. Publicado em: 23/05/2019
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11. Study of Cellulose Nanocrystals and Zinc Nitrate Hexahydrate Addition in Chitosan Hydrogels
In this study, chitosan hydrogels were produced with 0, 2, 4 and 6 wt% of cellulose nanocrystals (CNC) using hexahydrate zinc nitrate (Zn(NO3)2.6H2O) as a catalyst for chitosan crosslinking reaction. CNC´s size was estimated by dynamic light scattering (DLS) and surface charge by zeta potential. Hydrogels were characterized by rotational rheometer, swelling
Mat. Res.. Publicado em: 25/04/2019
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12. Physiology and quality of 'Tahiti' acid lime coated with nanocellulose-based nanocomposites
Abstract The aim of this study was to evaluate the physiological response and quality of the ‘Tahiti’ acid lime coated with carboxymethylcellulose (N-CMC), pectin (N-PEC) and starch (N-ST) nanocomposites based on cellulose nanocrystals (NC). Respiratory rate, ethylene production, loss of fresh weight, total chlorophyll and fruit firmness were evaluated
Food Sci. Technol. Publicado em: 29/11/2018