scholarly journals SISTEMA DE BAIXO CUSTO PARA EXECUÇÃO E MONITORAMENTO ON-LINE DE REAÇÕES FOTOCATALÍTICAS: APLICAÇÃO EM REDUÇÃO DE NITRO-FENOL

Química Nova ◽  
2021 ◽  
Author(s):  
Byanca Salvati ◽  
Sirlon Blaskievicz ◽  
Patricia Corradini ◽  
Lucia Mascaro
Keyword(s):  
Organic Contaminants ◽  
Online Monitoring ◽  
Low Cost ◽  
Kinetic Curve ◽  
Reduction Reaction ◽  
Cost System ◽  
Research And Teaching ◽  
Chromophore Concentration ◽  
On Line ◽  
Global Concern

LOW-COST SYSTEM FOR ONLINE MONITORING OF PHOTOCALYTICAL REACTIONS: APPLICATION IN NITROPHENOL. There is a global concern with pollutants and organic contaminants and efficient and inexpensive methods are sought for the treatment of these toxic products. Generally, large volume reactors and the use of expensive equipment are required to monitor a photoreaction. The present work proposes the construction of a colorimetric equipment, which allows the online monitoring of photoreactions, using low-cost materials that allow the analysis from small aliquots. To show the applicability of the system, we studied the reduction reaction of 4-nitrophenol (4NP) with NaBH4. The impedimetric sensor enabled to construct the kinetic curve of the decrease in the chromophore band. It was possible to observe that the 4NP reduction reaction depends on: (i) chromophore concentration; (ii) stability of the reducing agent and; (iii) repulsion between the anions. The system developed here opens doors, as it can be used using a photocatalyst in the form of film, and it has also proved to be an inexpensive alternative for both research and teaching laboratories, as it allows the execution of chemical physics practices such as kinetic monitoring of reactions and mathematical adjustment of the curves.

A low-cost system for computerized rodent weight logging with statistical analysis

1989 ◽  
Vol 23 (1) ◽  
pp. 39-42
Author(s):  
L. S. Young ◽  
R. J. East ◽  
T. Fearn
Keyword(s):  
Statistical Analysis ◽  
Data Collection ◽  
Personal Computer ◽  
Low Cost ◽  
Computer Programs ◽  
Current Loop ◽  
Computer Data ◽  
Cost System ◽  
On Line ◽  
Weight Data

A system comprising a suite of 4 computer programs has been developed for on-line rodent weight data collection and statistical analysis using an IBM personal computer. Data can be collected from up to 3 separate trials simultaneously, and can be stored for later statistical analysis. Mettler balances were used for the animal weighing. A Mettler current loop adapter and a multiplexer were used to interface the balances with the computer.

Low-Cost System Handles Patient Phone Calls

2007 ◽  
Vol 40 (11) ◽  
pp. 53
Author(s):  
BRUCE K. DIXON
Keyword(s):  
Low Cost ◽  
Cost System ◽  
Phone Calls

Intelligent, low-cost system for fume control during laser material processing

2005 ◽  
Author(s):  
Ramin Sattari ◽  
Stephan Barcikowski ◽  
Thomas Püster ◽  
Andreas Ostendorf ◽  
Heinz Haferkamp
Keyword(s):  
Material Processing ◽  
Low Cost ◽  
Laser Material Processing ◽  
Laser Material ◽  
Cost System

Graphene Supported Tungsten Carbide as Catalyst for Electrochemical Reduction of CO2

2019 ◽  
Author(s):  
Sahithi Ananthaneni ◽  
Rees Rankin
Keyword(s):  
Tungsten Carbide ◽  
Electrochemical Reduction ◽  
Low Cost ◽  
Co2 Reduction ◽  
Platinum Group Metal ◽  
Reduction Reaction ◽  
Metal Carbides ◽  
Depth Study ◽  
Reduction Of Co2 ◽  
Co2 Reduction Reaction

<div>Electrochemical reduction of CO2 to useful chemical and fuels in an energy efficient way is currently an expensive and inefficient process. Recently, low-cost transition metal-carbides (TMCs) are proven to exhibit similar electronic structure similarities to Platinum-Group-Metal (PGM) catalysts and hence can be good substitutes for some important reduction reactions. In this work, we test graphenesupported WC (Tungsten Carbide) nanocluster as an electrocatalyst for the CO2 reduction reaction. Specifically, we perform DFT studies to understand various possible reaction mechanisms and determine the lowest thermodynamic energy landscape of CO2 reduction to various products such as CO, HCOOH, CH3OH, and CH4. This in-depth study of reaction energetics could lead to improvements and develop more efficient electrocatalysts for CO2 reduction.<br></div>

scholarly journals Defect and Doping Co-Engineered Non-Metal Nanocarbon ORR Electrocatalyst

2021 ◽  
Vol 13 (1) ◽  
Author(s):  
Jian Zhang ◽  
Jingjing Zhang ◽  
Feng He ◽  
Yijun Chen ◽  
Jiawei Zhu ◽  
...  
Keyword(s):  
Rational Design ◽  
Low Cost ◽  
Reduction Reaction ◽  
Defect Engineering ◽  
Heteroatom Doping ◽  
Competitive Activity ◽  
Design And Manufacturing ◽  
Earth Abundant ◽  
Induced Defects ◽  
Carbon Based

AbstractExploring low-cost and earth-abundant oxygen reduction reaction (ORR) electrocatalyst is essential for fuel cells and metal–air batteries. Among them, non-metal nanocarbon with multiple advantages of low cost, abundance, high conductivity, good durability, and competitive activity has attracted intense interest in recent years. The enhanced ORR activities of the nanocarbons are normally thought to originate from heteroatom (e.g., N, B, P, or S) doping or various induced defects. However, in practice, carbon-based materials usually contain both dopants and defects. In this regard, in terms of the co-engineering of heteroatom doping and defect inducing, we present an overview of recent advances in developing non-metal carbon-based electrocatalysts for the ORR. The characteristics, ORR performance, and the related mechanism of these functionalized nanocarbons by heteroatom doping, defect inducing, and in particular their synergistic promotion effect are emphatically analyzed and discussed. Finally, the current issues and perspectives in developing carbon-based electrocatalysts from both of heteroatom doping and defect engineering are proposed. This review will be beneficial for the rational design and manufacturing of highly efficient carbon-based materials for electrocatalysis.

scholarly journals Iron, Nitrogen Co‐Doped Carbon Spheres as Low Cost, Scalable Electrocatalysts for the Oxygen Reduction Reaction

2021 ◽  
pp. 2102974
Author(s):  
Jingyu Feng ◽  
Rongsheng Cai ◽  
Emanuele Magliocca ◽  
Hui Luo ◽  
Luke Higgins ◽  
...  
Keyword(s):  
Oxygen Reduction Reaction ◽  
Oxygen Reduction ◽  
Low Cost ◽  
Reduction Reaction ◽  
Carbon Spheres ◽  
Co Doped

Tailoring the Co4+/Co3+ active sites in single perovskite as a bifunctional catalyst for oxygen electrode reactions "

2021 ◽  
Author(s):  
Song-Jeng Isaac Huang ◽  
Adil Muneeb ◽  
Sabhapathy Palani ◽  
Anjaiah Sheelam ◽  
Bayikadi Khasimsaheb ◽  
...  
Keyword(s):  
Oxygen Evolution Reaction ◽  
Precious Metal ◽  
Active Sites ◽  
Low Cost ◽  
Bifunctional Catalyst ◽  
Oxygen Electrode ◽  
Reduction Reaction ◽  
New Class ◽  
Electrode Reactions ◽  
Energy Conversion Devices

Developing a non-precious metal electrocatalyst for oxygen evolution reaction (OER) and oxygen reduction reaction (ORR) is desirable for low-cost energy conversion devices. Herein, we designed and developed a new class...

scholarly journals Immobilization of Pseudomonas aeruginosa static biomass on eggshell powder for on-line preconcentration and determination of Cr (VI)

2020 ◽  
Vol 18 (1) ◽  
pp. 303-313 ◽  
Author(s):  
Aamir Rasheed ◽  
Tahseen Ghous ◽  
Sumaira Mumtaz ◽  
Muhammad Nadeem Zafar ◽  
Kalsoom Akhter ◽  
...  
Keyword(s):  
Pseudomonas Aeruginosa ◽  
Low Cost ◽  
Colorimetric Detection ◽  
Time Flow ◽  
Highly Sensitive ◽  
Glass Column ◽  
On Line ◽  
Preconcentration Time ◽  
Ultra Trace

AbstractIn the present work, a novel continuous flow system (CFS) is developed for the preconcentration and determination of Cr (VI) using Pseudomonas aeruginosa static biomass immobilized onto an effective and low-cost solid support of powdered eggshells. A mini glass column packed with the immobilized biosorbent is incorporated in a CFS for the preconcentration and determination of Cr (VI) from aqueous solutions. The method is based on preconcentration, washing and elution steps followed by colorimetric detection with 1,5-diphenyl carbazide in sulphuric acid. The effects of several variables such as pH, retention time, flow rate, eluent concentration and loaded volume are studied. Under optimal conditions, the CFS method has a linear range between 10 and 100 μg L-1 and a detection limit of 6.25 μg L-1 for the determination of Cr (VI). The sampling frequency is 10 samples per hour with a preconcentration time of 5 mins. Furthermore, after washing with a 0.1 M buffer (pH 3.0), the activity of the biosorbent is regenerated and remained comparable for more than 200 cycles. Scanning electron microscopy reveals a successful immobilization of biomass on eggshells powder and precipitation of Cr (VI) on the bacterial cell surface. The proposed method proves highly sensitive and could be suitable for the determination of Cr (VI) at an ultra-trace level.

scholarly journals A Low-cost System for High-frequency Solar Imagery and Power Data Acquisition

2021 ◽  
Vol 1826 (1) ◽  
pp. 012082
Author(s):  
G F Bassous ◽  
R F Calili ◽  
C R H Barbosa
Keyword(s):  
Data Acquisition ◽  
High Frequency ◽  
Low Cost ◽  
Cost System
Sign in / Sign up

Export Citation Format

Share Document