Demonstration of environmental chemistry with microscale chemistry and a low-cost four-led based photom

2018 ◽  
Vol 16 (4) ◽  
pp. 510
Author(s):  
Wai Kin Kee ◽  
Wing Hong Chan
Keyword(s):  
Phenolic Compounds ◽  
Environmental Chemistry ◽  
Low Cost ◽  
Light Sources ◽  
Electrochemical Degradation

<span>In this article, a four-LED based photometer, in which four LEDs are used as light sources, are demonstrated to be a useful instrument for the study of pollution problems caused by phenols and of their remediation by electrochemical degradation method and the iron (II) catalyzed homogeneous Fenton’s reaction. The fate of phenols can be monitored by the photometer via the 4-aminoantipyrine method. The results revealed that the latter method was a superior method to treat the phenolic compounds.</span>

scholarly journals A 40 Mb/s VLC System Reusing an Existing Large LED Panel in an Indoor Office Environment

Sensors ◽  
2021 ◽  
Vol 21 (5) ◽  
pp. 1697
Author(s):  
Xicong Li ◽  
Zabih Ghassemlooy ◽  
Stanislav Zvánovec ◽  
Paul Anthony Haigh
Keyword(s):  
Modulation Depth ◽  
Light Emitting Diode ◽  
Low Cost ◽  
Data Communication ◽  
Experimental System ◽  
Digital Signal ◽  
Visible Light Communication ◽  
Cost Driver ◽  
Limiting Factors ◽  
Light Sources

With advances in solid-state lighting, visible light communication (VLC) has emerged as a promising technology to enhance existing light-emitting diode (LED)-based lighting infrastructure by adding data communication capabilities to the illumination functionality. The last decade has witnessed the evolution of the VLC concept through global standardisation and product launches. Deploying VLC systems typically requires replacing existing light sources with new luminaires that are equipped with data communication functionality. To save the investment, it is clearly desirable to make the most of the existing illumination systems. This paper investigates the feasibility of adding data communication functionality to the existing lighting infrastructure. We do this by designing an experimental system in an indoor environment based on an off-the-shelf LED panel typically used in office environments, with the dimensions of 60 × 60 cm2. With minor modifications, the VLC function is implemented, and all of the modules of the LED panel are fully reused. A data rate of 40 Mb/s is supported at a distance of up to 2 m while using the multi-band carrierless amplitude and phase (CAP) modulation. Two main limiting factors for achieving higher data rates are observed. The first factor is the limited bandwidth of the LED string inside the panel. The second is the flicker due to the residual ripple of the bias current that is generated by the panel’s driver. Flicker is introduced by the low-cost driver, which provides bias currents that fluctuate in the low frequency range (less than several kilohertz). This significantly reduces the transmitter’s modulation depth. Concurrently, the driver can also introduce an effect that is similar to baseline wander at the receiver if the flicker is not completely filtered out. We also proposed a solution based on digital signal processing (DSP) to mitigate the flicker issue at the receiver side and its effectiveness has been confirmed.

scholarly journals An Automated Light Trap to Monitor Moths (Lepidoptera) Using Computer Vision-Based Tracking and Deep Learning

Sensors ◽  
2021 ◽  
Vol 21 (2) ◽  
pp. 343
Author(s):  
Kim Bjerge ◽  
Jakob Bonde Nielsen ◽  
Martin Videbæk Sepstrup ◽  
Flemming Helsing-Nielsen ◽  
Toke Thomas Høye
Keyword(s):  
Computer Vision ◽  
Deep Learning ◽  
Vision System ◽  
Low Cost ◽  
Light Trap ◽  
Automatic Monitoring ◽  
Light Sources ◽  
Monitoring Methods ◽  
Computer Vision System ◽  
Substantial Investment

Insect monitoring methods are typically very time-consuming and involve substantial investment in species identification following manual trapping in the field. Insect traps are often only serviced weekly, resulting in low temporal resolution of the monitoring data, which hampers the ecological interpretation. This paper presents a portable computer vision system capable of attracting and detecting live insects. More specifically, the paper proposes detection and classification of species by recording images of live individuals attracted to a light trap. An Automated Moth Trap (AMT) with multiple light sources and a camera was designed to attract and monitor live insects during twilight and night hours. A computer vision algorithm referred to as Moth Classification and Counting (MCC), based on deep learning analysis of the captured images, tracked and counted the number of insects and identified moth species. Observations over 48 nights resulted in the capture of more than 250,000 images with an average of 5675 images per night. A customized convolutional neural network was trained on 2000 labeled images of live moths represented by eight different classes, achieving a high validation F1-score of 0.93. The algorithm measured an average classification and tracking F1-score of 0.71 and a tracking detection rate of 0.79. Overall, the proposed computer vision system and algorithm showed promising results as a low-cost solution for non-destructive and automatic monitoring of moths.

LED Light Sources in Organic Synthesis: An Entry to A Novel Approach

2021 ◽  
Vol 18 ◽  
Author(s):  
Aparna Das
Keyword(s):  
Organic Compounds ◽  
Organic Synthesis ◽  
Photochemical Reaction ◽  
Low Cost ◽  
Environmentally Friendly ◽  
Photochemical Reactions ◽  
Light Sources ◽  
Blue Led ◽  
Oxidation Reduction ◽  
Novel Approach

: In recent years, photocatalytic technology has shown great potential as a low-cost, environmentally friendly, and sustainable technology. Compared to other light sources in photochemical reaction, LEDs have advantages in terms of efficiency, power, compatibility, and environmentally-friendly nature. This review highlights the most recent advances in LED-induced photochemical reactions. The effect of white and blue LEDs in reactions such as oxidation, reduction, cycloaddition, isomerization, and sensitization is discussed in detail. No other reviews have been published on the importance of white and blue LED sources in the photocatalysis of organic compounds. Considering all the facts, this review is highly significant and timely.

Air of the Anthropocene

2021 ◽  
Author(s):  
Francis Pope ◽  
Robin Price
Keyword(s):  
Air Pollution ◽  
Los Angeles ◽  
Low Cost ◽  
Measurement Techniques ◽  
Transformational Change ◽  
Ambient Air ◽  
Expert Advice ◽  
Light Sources ◽  
Anthropogenic Contamination ◽  
Science Collaboration

&lt;p&gt;Anthropogenic contamination of the atmosphere is causing both climate change and air pollution, which respectively represent the greatest long term and short term environmental risks to human and planetary health. The contamination is largely invisible and hence difficult to contextualise for non-expert audiences. This can lead to the problem being ignored; or where it is acknowledged, leading to feelings of helplessness and a lack of agency.&lt;/p&gt;&lt;p&gt;This project uses digital light painting to visualise and explore responses to particulate matter (PM) air pollution, in a variety of global locations, as a method for both public engagement and campaign work. This photographic technique combines long exposure with light sources digitally controlled by sensors, it builds upon the prior work of electronic pioneer Steve Mann (e.g. Mann et al. 2019) and more recent work visualising wifi strength (Arnall et al. 2013).&lt;/p&gt;&lt;p&gt;The five year art-science collaboration between Price and Pope has been highly successful. The Air of the Anthropocene project resulted in multiple gallery shows (including Los Angeles, Belfast and Birmingham). The media publicized it heavily, including Source Magazine, New Scientist and the Guardian. The physical art works were acquired by the Arts Council of Northern Ireland&amp;#8217;s public collection.&lt;/p&gt;&lt;p&gt;In this presentation, we will highlight the scientific and aesthetic underpinnings of the use of low cost air pollution sensors for data visualisation through light painting. Locations for visualizations were guided by expert advice from environmental scientists in global locations, including those in Europe, Africa, Asia and South America. In this sense the science informed the art. Also, since the code from the project ended being used by scientists, the art informed the science (e.g. Crilley et al. 2018).&lt;/p&gt;&lt;p&gt;We will highlight the efficacy of this image making approach as an engagement and advocacy tool, through case studies of its use in field campaigns in Ethiopia (2020) and Kampala (2018), investigating both indoor and outdoor air pollution.&amp;#160; Future possibilities of the approach to air pollution visualization will be discussed. This will include expanding the approach through open sourcing the project and its adaptation beyond lens based techniques into augmented reality camera phone use.&lt;/p&gt;&lt;p&gt;The projected next phase of the collaboration will work towards empowering interested citizens of the world to make their own creative, aesthetic representations of their environment and use these images as citizen activists to affect transformational change in their own localities. Through adopting open source methodologies it is hoped that sustainability beyond the timescale and budget of the initial project with lasting legacy will be achieved.&lt;/p&gt;&lt;p&gt;&amp;#160;&lt;/p&gt;&lt;p&gt;Arnall et al, 2013. Immaterials: light painting WiFi. Significance, 10(4). https://doi.org/10.1111/j.1740-9713.2013.00683.x&amp;#160;&lt;/p&gt;&lt;p&gt;Crilley et al, 2018. Evaluation of a low-cost optical particle counter (Alphasense OPC-N2) for ambient air monitoring. Atmospheric Measurement Techniques. https://doi.org/10.5194/amt-11-709-2018&amp;#160;&lt;/p&gt;&lt;p&gt;Mann et al 2019, June. Making Sensors Tangible with Long-exposure Photography. In The 5th ACM Workshop on Wearable Systems and Applications. https://doi.org/10.1145/3325424.3329668&lt;/p&gt;

First application of different Chlorella sp. microalgal strains for the treatment of vegetation waters derived from unconventional oil extractions enriched with citrus byproducts

2021 ◽  
Author(s):  
Carolina Chiellini ◽  
Monica Macaluso ◽  
Adriana Ciurli ◽  
Lorenzo Guglielminetti ◽  
Isabella Taglieri ◽  
...  
Keyword(s):  
Phenolic Compounds ◽  
Olive Oil ◽  
Low Cost ◽  
Environmental Pollutants ◽  
Extraction Process ◽  
Total Phenolic ◽  
Mediterranean Countries ◽  
Extraction Processes ◽  
The Mediterranean ◽  
Vegetation Water

The Mediterranean diet has among its cornerstones the use of olive oil for its nutraceutical and organoleptic properties. Despite the numerous merits, olive-oil mill wastewater (OMWW), which is generated by the olive-oil extraction process, is one of the most serious environmental pollutants in the Mediterranean countries. The polluting potential of OMWW is due to its high content of tannins, polyphenols, polyalcohols, pectins and lipids. In this experiment, we tested the ability of five microalgae of the Chlorella group (SEC_LI_ChL_1, CL-Sc, CL-Ch, FB and Idr) in lowering the percentage of total phenolic compounds in vegetation water. In order to close the recovery cycle of a fortified citrus olive oils previously developed, we tested the vegetation wa-ter obtained with three different extraction processes (conventional, lemon and orange peels) at three concentrations each (10%, 25% and 50%). Results showed that strains Idr, FB and CL-Sc from the Lake Massaciuccoli can tolerate vegetation water from conventional and lemon peels extraction up to 25%; these strains can also reduce the phenolic compounds within the tests. The results demonstrate that the application of microalgae for OMWW treatment represent an inter-esting opportunity, and an eco-friendly low-cost solution to be developed within the companies as a full-scale approach.

Phytochemicals as Potential Inhibitors of Advanced Glycation End Products: Health Aspects and Patent Survey

2021 ◽  
Vol 12 ◽  
Author(s):  
Annayara C. F. Fernandes ◽  
Jeane B. Melo ◽  
Vanize M. Genova ◽  
Ádina L. Santana ◽  
Gabriela Macedo
Keyword(s):  
Phenolic Compounds ◽  
Inflammatory Responses ◽  
Low Cost ◽  
Advanced Glycation Endproducts ◽  
Advanced Glycation ◽  
Glycation Endproducts ◽  
Synthetic Drugs ◽  
Peanut Skins

Background: Glycation is a chemical reaction that synthesize advanced glycation endproducts (AGEs). The AGEs irreversibly damage macromolecules present in tissues and organs, leading to the impairment of biological functions. For instance, the accumulation of AGEs induces oxidative stress and consequently inflammatory responses in human body, leading to the on set/worsening of diseases, including obesity, asthma, cognitive impairment, and cancer. There is a current demand on natural and low-cost sources of antiglycant agents. As a result, food phytochemicals presented promising results to inhibit glycation and consequently, the formation of AGEs. Objective: Here, we describe the mechanism of glycation on the worsening of diseases, the methods os detection, and the current findings on the use of phytochemicals (phenolic compounds, phytosterols, carotenoids, terpenes and vitamins) as natural therapeuticals to inhibit health damages via inhibition of AGEs in vitro and in vivo. Methods: This manuscript reviewed publications available in the PubMed and Science Direct databases dated from the last 20 years on the uses of phytochemicals to inhibit the AGEs in vitro and in vivo. Also, recent patents on the use of anti-glycant drugs were reviewed using the Google Advanced Patents database. Results and Discussion: Phenolic compounds have been mostly studied to inhibit AGEs. Food phytochemicals derived from agroindustry wastes, including peanut skins, and the bagasses derived from citrus and grapes are promising antiglycant agents via scavenging of free radicals, metal ions, the suppression of metabolic pathways that induces inflammation, the activation of pathways that promote antioxidant defense, the blocking of AGE connection with the receptor for advanced glycation endproducts (RAGE). Conclusion: Phytochemicals derived from agroindustry are promising anti-glycants, which can be included to replace synthetic drugs for AGE inhibition, and consequently to act as a therapeutical strategy to prevent and treat diseases caused by AGEs, including diabetes, ovarian cancer, osteoporosis, and Alzheimer’s disease.

scholarly journals The Use of Algae and Fungi for Removal of Pharmaceuticals by Bioremediation and Biosorption Processes: A Review

Water ◽  
2019 ◽  
Vol 11 (8) ◽  
pp. 1555 ◽  
Author(s):  
Andreia Silva ◽  
Cristina Delerue-Matos ◽  
Sónia Figueiredo ◽  
Olga Freitas
Keyword(s):  
Aquatic Environment ◽  
Capital Investment ◽  
Environmental Chemistry ◽  
Wastewater Treatment Plants ◽  
Low Cost ◽  
Treatment Processes ◽  
Operation Costs ◽  
Emerging Issues ◽  
By Products ◽  
Easy Operation

The occurrence and fate of pharmaceuticals in the aquatic environment is recognized as one of the emerging issues in environmental chemistry. Conventional wastewater treatment plants (WWTPs) are not designed to remove pharmaceuticals (and their metabolites) from domestic wastewaters. The treatability of pharmaceutical compounds in WWTPs varies considerably depending on the type of compound since their biodegradability can differ significantly. As a consequence, they may reach the aquatic environment, directly or by leaching of the sludge produced by these facilities. Currently, the technologies under research for the removal of pharmaceuticals, namely membrane technologies and advanced oxidation processes, have high operation costs related to energy and chemical consumption. When chemical reactions are involved, other aspects to consider include the formation of harmful reaction by-products and the management of the toxic sludge produced. Research is needed in order to develop economic and sustainable treatment processes, such as bioremediation and biosorption. The use of low-cost materials, such as biological matrices (e.g., algae and fungi), has advantages such as low capital investment, easy operation, low operation costs, and the non-formation of degradation by-products. An extensive review of existing research on this subject is presented.

scholarly journals Spectrophotometric and Smartphone-Assisted Determination of Phenolic Compounds Using Crude Eggplant Extract

Molecules ◽  
2019 ◽  
Vol 24 (23) ◽  
pp. 4407 ◽  
Author(s):  
M.A. Morosanova ◽  
A.S. Bashkatova ◽  
E.I. Morosanova
Keyword(s):  
Phenolic Compounds ◽  
Chlorogenic Acid ◽  
Caffeic Acid ◽  
Polyphenol Oxidase ◽  
Oxidase Activity ◽  
Biological Fluids ◽  
Low Cost ◽  
Analytical Signal ◽  
Polyphenol Oxidase Activity

In order to develop a simple, reliable and low cost enzymatic method for the determination of phenolic compounds we studied polyphenol oxidase activity of crude eggplant (S. melongena) extract using 13 phenolic compounds. Catechol, caffeic and chlorogenic acids, and L-DOPA have been rapidly oxidized with the formation of colored products. Monophenolic compounds have been oxidized at a much slower speed. Ferulic acid, quercetin, rutin, and dihydroquercetin have been found to inhibit polyphenol oxidase activity of crude eggplant extract. The influence of pH, temperature, crude eggplant extract amount, and 3-methyl-2-benzothiazolinone hydrazone (MBTH) concentration on the oxidation of catechol, caffeic acid, chlorogenic acid, and L-DOPA has been investigated spectrophotometrically. Michaelis constants values decrease by a factor of 2 to 3 in the presence of MBTH. Spectrophotometric (cuvette and microplate variants) and smartphone-assisted procedures for phenolic compounds determination have been proposed. Average saturation values (HSV color model) of the images of the microplate wells have been chosen as the analytical signal for smartphone-assisted procedure. LOD values for catechol, caffeic acid, chlorogenic acid, and L-DOPA equaled 5.1, 6.3, 5.8 and 30.0 µM (cuvette procedure), 12.2, 13.2, 13.2 and 80.4 µM (microplate procedure), and 23.5, 26.4, 20.8 and 120.6 µM (smartphone procedure). All the variants have been successfully applied for fast (4-5 min) and simple TPC determination in plant derived products and L-DOPA determination in model biological fluids. The values found with smartphone procedure are in good agreement with both spectrophotometric procedures values and reference values. Using crude eggplant extract- mediated reactions combined with smartphone camera detection has allowed creating low-cost, reliable and environmentally friendly analytical method for the determination of phenolic compounds.

Integration of OLEDs in Textiles

2012 ◽  
Vol 80 ◽  
pp. 14-21 ◽  
Author(s):  
Silvia Janietz ◽  
Björn Gruber ◽  
Sylvia Schattauer ◽  
Kerstin Schulze
Keyword(s):  
Low Cost ◽  
Glass Fibers ◽  
Hole Transport ◽  
Light Sources ◽  
Electronic Textiles ◽  
Large Area ◽  
Solution Processed ◽  
Hole Transport Layers ◽  
First Results ◽  
Planar Substrates

In place of silicon, which is normally used in microelectronics, organic materials offer the opportunity to produce devices on large area, low-cost and plastic planar substrates. These materials are attracting increased attention also in the field of electronic-textiles (e-textiles) because they show an interesting combination of electronic and mechanical properties that can be favourably exploited in smart textiles. A key step for the integration of mass production of e-textiles is to combine electronic production with textile manufactures. In the last years, progress has been achieved in the development of fibers and their processing for application in e-textiles. The application ranged from fabric integrated light sources to low cost solid state lighting for protection and security. Here research results are presented regarding the integration of encapsulated glass OLEDs and additionally OLEDs fabricated on flexible high barrier substrates which were integrated into textiles. On the other hand, the first results concerning the realization of an OLED on cylindrical surfaces based on solution processed technologies which is a first step in the direction of low cost processing will be discussed. A simple, inverted planar construction prepared from solution was realized. This preliminary work was the precondition for the development of a fiber based OLED. In addition, OLEDs that were prepared using glass fibers as substrates and solution processed active and hole-transport layers will be shown.

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