Acid Base
Mostrando 1-12 de 3341 artigos, teses e dissertações.
-
1. A novel fluorescence sensor for the detection of chloride ion in artificial sweat and environmental water with nitrogen-doped graphene quantum dots
A new fluorescent detection route for chloride ion was designed with Nitrogen-doped graphene quantum dots (N-GQDs), which were prepared by a traditional hydrothermal method with citric acid as carbon source and urea as nitrogen source. The prepared N-GQDs solution was light yellow, and the freeze-dried solid was black. It emitted blue light under ultraviolet
Química Nova. Publicado em: 2022
-
2. Preparation of SAPO-34-Based Catalyst for Conversion of Fructose to 5-Hydroxymethylfurfural
Solid acid-catalyzed dehydration of fructose to produce 5-hydroxymethylfurfural (5-HMF) has been a hotspot in biomass conversion research in recent years. In this study, a novel SAPO-34-based catalyst was prepared by consecutive steps of titanium doping, sulfuric acid impregnation, and sulfonic acid functionalization. Characterization of the catalyst with X-
J. Braz. Chem. Soc.. Publicado em: 2021-08
-
3. Allyl Dibenzoylmethane Derivative: Antimelanoma Activity and Study of Its Molecular Mechanism of Interaction with DNA
In this study, we assessed the cytotoxic effect of 1,3-diphenyl-2-allyl-1,3-propanedione (DPAP) on B16F10 and Tm5 melanoma cells and investigated its interaction with DNA (deoxyribonucleic acid) using optical tweezers. The compound showed to be effective against B16F10 cells with selectivity index (SI) of 7.92 and interaction to the outer surface of the doub
J. Braz. Chem. Soc.. Publicado em: 2021-07
-
4. INCORPORAÇÃO DE RODAMINA B EM MEMBRANA DE POLIAMIDA PELO MÉTODO DA ADSORÇÃO
We have incorporated rhodamine into polyamide membranes by additive manufacture selective laser sintering technology. Incorporation into 0.5 cm2 membranes was conducted at different pH values and constant temperature of 25 oC. The amounts of incorporated dye were determined by a calibration curve, and analyses showed rhodamine incorporation in the order of 1
Quím. Nova. Publicado em: 2021-02
-
5. Using static, kinetic and metal mobility procedures to evaluate possibilities of coal waste land disposal at Moatize Mine, Mozambique
Abstract Coal mine waste rocks produced during mining and beneficiation can affect the environment due to land degradation and acid mine drainage generation. However, proper characterization and treatment of mineral processing wastes creates options for safe disposal, enhancing the environmental performance. The aim of this study was to use static and kineti
REM, Int. Eng. J.. Publicado em: 2020-12
-
6. INFLUÊNCIA DA FORÇA IÔNICA NA ESTIMATIVA DE pKa POR MÉTODO VOLTAMÉTRICO
The voltammetry is an important analytical technique and also useful for pKa determination. It is a usual procedure of this technique to employ inert electrolyte concentration 100 times higher than redox compound concentration further a pH buffer. However, the ionic strength changes with the solution pH. In this work, we study the consequences of this proced
Quím. Nova. Publicado em: 2020-12
-
7. Effects of citrox treatment on the survival of Methicillin-Resistant Staphylococcus aureus (MRSA) in chicken fillets packed under vacuum
Abstract Citrox has natural antibacterial effect against many foodborne pathogens and contaminated bacteria. It mainly contains citric acid, ascorbic acid, and malic acid. We studied the antimicrobial effects of citrox solution (1% and 2%) on the total viable count of methicillin-resistant Staphylococcus aureus (MRSA) on chicken meat fillet. The samples were
Food Sci. Technol. Publicado em: 2020-09
-
8. PROCESSING OF A METAL CONCENTRATE FROM GROUND WASTE PRINTED CIRCUIT BOARDS IN ACIDIC MEDIA USING HYDROGEN PEROXIDE AS OXIDANT
The recovery of precious and base metals of a metal concentrate from ground waste printed circuit boards (PCBs) is described in detail. Samples were treated with NaOHaq. to remove the soldering mask. Experiments were performed in acidic medium (HF, H2SO4, CH3COOH or H3PO4) using H2O2 as oxidant. Base metals were leached in high yields (>99 wt.%) at ~40 ºC a
Quím. Nova. Publicado em: 20/07/2020
-
9. Specific Disulfide Bond Formation Directed by Peptide Nucleic Acids
In this study, we successfully demonstrated a strategy for specific disulfide bond formation by hybridization of two complementary peptide nucleic acid strands. Peptides were linked to the pair of complementary peptide nucleic acids by native chemical ligation, respectively, and base pairing drove the two peptides into close proximity for interchain disulfid
J. Braz. Chem. Soc.. Publicado em: 2020-05
-
10. A Highly Selective Colorimetric Sensor for Cysteine Detection
Introducing a hybrid xanthene as a fluorophore, an ‘ensemble’-based fluorescent sensor (E)-2-(6-(diethylamino)-2-((2-hydroxyphenylimino)methyl)-3-oxo-3H-xanthen-9-yl)benzoic acid (a) was designed and synthesised for detection of cysteine. Cysteine can release CuII ion from the non-fluorescent a-CuII complex. Then hydrolytic cleavage of Schiff base a prod
J. Braz. Chem. Soc.. Publicado em: 2020-02
-
11. Extratos de Lilium sp., Agapanthus sp. e Hydrangea sp.: comportamento como indicadores naturais em diferentes faixas de pH
This experimental activity proposes the use of lily (Lilium sp.), agapanthus (Agapanthus sp.) and hydrangea (Hydrangea sp.) extracts to investigate the colorimetric profile of each extract between pH 1-14. Water, ethanol and ethanol/HCl 1% (w/w) were used as extractive solvents. Among the flowers tested, the extracts of orange lily and burnt yellow lily were
Quím. Nova. Publicado em: 2020-02
-
12. Effects of Flammulinavelutipes Stem Base on Microflora and Volatile Fatty Acids In Caecum of Growing Layers under Heat Stress Condition
ABSTRACT The present study was undertaken to investigate the effects of Flammulinavelutipes stem base (FVS) on growth performance, microbial flora and volatile fatty acids of growing layers under heat stress condition. A total of 72 ISA Brown hens were randomly divided into six treatments: thermoneutral temperature control group (CON), heat stress control gr
Braz. J. Poult. Sci.. Publicado em: 20/12/2019