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Articles 1 - 30 of 54

Full-Text Articles in Chemistry

Synergistic Effect Of Acylpyrazolone Integrated With Multiwalled Carbon Nanotubes On The Electrochemical Analysis Of Ascorbic Acid, Emi Norzehan Mohamad Mahbob, Mohamad Syahrizal Ahmad, Illyas Md Isa, Norhayati Hashim, Anwar Ul-Hamid, Mohamad Idris Saidin, Suyanta Suyanta, Sofian Ibrahim Mar 2024

Synergistic Effect Of Acylpyrazolone Integrated With Multiwalled Carbon Nanotubes On The Electrochemical Analysis Of Ascorbic Acid, Emi Norzehan Mohamad Mahbob, Mohamad Syahrizal Ahmad, Illyas Md Isa, Norhayati Hashim, Anwar Ul-Hamid, Mohamad Idris Saidin, Suyanta Suyanta, Sofian Ibrahim

Makara Journal of Science

Square wave voltammetry, cyclic voltammetry, chronocoulometry, and electrochemical impedance spectroscopy were employed to assess ascorbic acid’s electrochemical behavior in multiwalled carbon nanotubes (MWCNTs)/carbon paste electrode (CPE) modified by 1-phenyl-3-methyl-4-metafluorobenzoyl-5-pyrazolone (HPMmFBP). The ascorbic acid’s irreversible oxidation peak appeared at approximately 0.5 V. The shifting of the peak potential at the pH range of 6.0–8.4 showed the involvement of protons in the ascorbic acid oxidation. Moreover, the shifting of the peak potential with scan rate in the range of 0.07–0.4 V/s confirmed that the oxidation reaction was irreversible. Under optimized conditions, the oxidative peak current showed linear dependence on the ascorbic acid’s …

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Green Synthesized Silver Nanoparticles-Based Sensing For Monitoring Water Pollution: An Updated Review, Muhamad Allan Serunting, Muhammad Ali Zulfikar, Henry Setiyanto, Dian Ayu Setyorini, Vienna Saraswaty Nov 2023

Green Synthesized Silver Nanoparticles-Based Sensing For Monitoring Water Pollution: An Updated Review, Muhamad Allan Serunting, Muhammad Ali Zulfikar, Henry Setiyanto, Dian Ayu Setyorini, Vienna Saraswaty

Karbala International Journal of Modern Science

Water is a basic human need and has been heavily contaminated. Therefore, it becomes a concern to remove the pollutant and monitor its quality. The removal methods include precipitation, filtration, adsorption, and photodegradation. Meanwhile, the monitoring can be done by measuring and analyzing the contaminant using spectrophotometry and chromatography. Nevertheless, those methods usually need a complicated preparation, and are expensive. Thus, a simple method is necessary to overcome these drawbacks by developing a sensor. In recent years, the sensor performance has been enhanced by using nanomaterials, such as silver nanoparticles (AgNPs). AgNPs can be synthesized using plant extracts through a …

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Synthesis, Characterization, And Photophysical And Fluorescence Sensor Behaviors Of A New Water-Soluble Double-Bridged Naphthalene Diimide Appended Cyclotriphosphazene, Süreyya Oğuz Tümay, Serkan Yeşi̇lot Oct 2023

Synthesis, Characterization, And Photophysical And Fluorescence Sensor Behaviors Of A New Water-Soluble Double-Bridged Naphthalene Diimide Appended Cyclotriphosphazene, Süreyya Oğuz Tümay, Serkan Yeşi̇lot

Turkish Journal of Chemistry

A new water-soluble template of double-bridged naphthalene diimide appended cyclotriphosphazene was prepared, and its photophysical and sensor behaviors were evaluated. The characterization of novel double-bridged naphthalene diimide appended cyclotriphosphazene (6) was carried out by NMR (1 H, 13C, 31P) and mass spectroscopies. The photophysical behaviors of compound 6 were evaluated by UV-Vis absorption and fluorescence spectroscopies in various solvent systems and different concentrations. As an application for usability of the obtained water-soluble template in different applications, the fluorescence sensor property of compound 6 was investigated in the presence of many different competing species (organic acids, saccharides, nitroaromatic compounds, anions, and …

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Advanced Tetra Amino (Ata-100) Cobalt(Ii) Phthalocyanine-Based Metallo-Covalent Organic Polymer For Sensitively Detecting Volatile Organic Compounds, Günseli̇ Güney, Gülay Altindemi̇r Kaplan, Ci̇hat Taşaltin, İlke Gürol Oct 2023

Advanced Tetra Amino (Ata-100) Cobalt(Ii) Phthalocyanine-Based Metallo-Covalent Organic Polymer For Sensitively Detecting Volatile Organic Compounds, Günseli̇ Güney, Gülay Altindemi̇r Kaplan, Ci̇hat Taşaltin, İlke Gürol

Turkish Journal of Chemistry

The synthesis and characterization of a novel covalent organic polymer cobalt (II) phthalocyanine (ATA-100) including tetra amino group is described for the first time. This covalent organic polymer (COP) is characterized by FTIR, TGA, RAMAN, PXRD, and SEM-EDS. The developed sensor is tested for acetone, ethyl butyrate, n-hexane, chloroform, and n-butyraldehyde in a range of 80-10,900 ppm. ATA-100 showed the highest sensitivity for ethyl butyrate. The results have confirmed the possibility of utilizing ATA-100 COP-based surface acoustic wave (SAW) sensors for a wide variety of applications, including indoor air quality and environmental monitoring of volatile organic compounds (VOCs).

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A Work Towards A Single-Bridge Hydrazine Sensor, Brenden Jay Schmeltz Oct 2023

A Work Towards A Single-Bridge Hydrazine Sensor, Brenden Jay Schmeltz

Theses and Dissertations

Hydrazine can currently be detected by irreversible methods, Carbazolopyridinophane (2,18-Dithia[3][1,8]carbazolo[3][2,6]pyridinophane) CP was synthesized by Brown et al. to detect hydrazine in real-time while also being reversible. The threshold for detection was 100 ppb, regulatory use requires 10 ppb as this is when permanent damage to humans can be caused. A more sensitive sensor will allow for safer workplaces for many people. A single, 3-atom bridge sensor will further examine the photophysical capabilities of carbazole-pyridine as an emitter/quencher pair. 1-Carbazole-1-methylpyridyl-2methyl sulfide SBCP will allow freedom of rotation as well as the bending of the bridge. These benefits will introduce conformers which …

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Green Synthesis Of Nanoparticles And Their Utilization In Electrochemical Detection Of Catechol- Or Phenol-Based Substances, Daniel Laurence Myers Iii Jan 2023

Green Synthesis Of Nanoparticles And Their Utilization In Electrochemical Detection Of Catechol- Or Phenol-Based Substances, Daniel Laurence Myers Iii

Browse all Theses and Dissertations

PART A: GREEN SYNTHESIS OF COPPER NANOPARTICLES AND THEIR UTILIZATION IN THE DETECTION OF NEUROTRANSMITTERS Neurotransmitters, such as dopamine and epinephrine, are chemicals frequently found in the brain and are responsible for a number of human moods, needs, and emotions.1, 2 Detection of such neurotransmitters allows for a better judgement of a person’s physical and mental state, a utility that is vital in determining the presence of disease and mental illnesses.2 Electrochemical detectors used for such detections are often modified by materials such as metal nanoparticles.3 However, synthesizing nanoparticles can involve or produce chemicals, ammonium hydroxide among them, that are …

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Development Of The Implementation Of Iot Monitoring System Based On Node-Red Technology, Anvar Kabulov, Inomjon Yarashov, Salamat Mirzataev Jun 2022

Development Of The Implementation Of Iot Monitoring System Based On Node-Red Technology, Anvar Kabulov, Inomjon Yarashov, Salamat Mirzataev

Karakalpak Scientific Journal

This article describes how to design and implement a process for storing environmental information in a database using the Internet of Things. The problems that need to be solved with the help of this IoT system are the growing demand for forecasts in the world, the demand of the world market for a new sustainable method of implementing the digitization environment through the Internet of Things. The design was implemented using Arduino, Node-Red and sensors, selected when choosing a component based on the required parameters and sent to the database for monitoring and processing. A study of previous work and …

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Electrochemical Voltammetric Behavior Of Sulfur Mustard On The Bare Pt Electrode, Yu-Lin Yang, Jie Sun, Tian Zhou, Ji-Gang Li, Shou-Ping Wei May 2022

Electrochemical Voltammetric Behavior Of Sulfur Mustard On The Bare Pt Electrode, Yu-Lin Yang, Jie Sun, Tian Zhou, Ji-Gang Li, Shou-Ping Wei

Journal of Electrochemistry

The sulfur mustard (bis(2-chloroethyl) sulphide, HD), one of highly toxic chemical weapon agents, can damage the alive tissue cells (such as skin, lung, respiratory mucosa and so on), and cause carcinogenic and mutagenic effects for a long time exposure, which imposes a great threat not only to the human health, but also to the sustainable development of the society. With its convenience, high sensitivity and rapid response, electrochemical technology exhibits considerable potential in the field-deployed detection toward HD, but the related reports are rare. Herein, the electrochemical behavior of HD on the bare Pt electrode was investigated by electrochemical measurements, …

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Characterization Of Bimetallic Silver-Copper Nanoinks With Hydroxyethyl-Cellulose Additives, Daniel Brunick May 2022

Characterization Of Bimetallic Silver-Copper Nanoinks With Hydroxyethyl-Cellulose Additives, Daniel Brunick

Undergraduate Honors Theses

Coinage metal nanoparticles remain an intriguing subject for research due to their industrial versatility. Primary applications of coinage metal nanoparticles include printed electronics, solar panels, and sensors. Inks formulated with the nanoparticles are conductive and thus useful for fabricating sensors. Silver-copper nanoalloy inks are viable for the fabrication of flexible sensing devices for the detection of volatile organic compounds. One of the challenges is the ability to synthesize composition-controllable alloy nanoparticles at room temperature through wet chemical methods and achieve controllable sintering at room temperature. This work addresses the challenges by investigating the room-temperature synthesis of silver-copper alloy nanoparticles and …

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Experimental Physical Chemistry Applications For Material Science: The Neutron Vibrational Spectrum Of Biaxially-Oriented Pet And Hkust-1 As A Qcm-Based Ethylene Sensor, Zachary D. Stroupe May 2022

Experimental Physical Chemistry Applications For Material Science: The Neutron Vibrational Spectrum Of Biaxially-Oriented Pet And Hkust-1 As A Qcm-Based Ethylene Sensor, Zachary D. Stroupe

Doctoral Dissertations

This work is divided into two comprehensive subjects exploiting fundamental properties of physical chemistry to understand applied materials. The two subjects will be: the inelastic neutron scattering of thin polyethylene terephthalate (PET) films and the design and development of a quartz crystal microbalance-based ethylene detector. For the work involving the thin films, the inelastic neutron scattering (INS) was accomplished using the high flux of the VISION vibrational spectrometer at the Spallation Neutron Source yielding the highest quality data currently available. The torsional vibrational modes of biaxially-oriented PET (bPET) will be reported with the help of DFT calculations to aid in …

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Structural, Charge Transport, Gas Sensing, Magnetic, Pseudocapacitive, And Electrocatalytic Properties Of Perovskite Oxides., Surendra Bahadur Karki May 2022

Structural, Charge Transport, Gas Sensing, Magnetic, Pseudocapacitive, And Electrocatalytic Properties Of Perovskite Oxides., Surendra Bahadur Karki

Electronic Theses and Dissertations

Perovskites are functional materials with the general formula ABO3 (A = alkali, alkaline earth or lanthanoid cations and B = transition metal or main group cations). These materials are marked by a variety of crystal structures and interesting properties such as colossal magnetoresistance, ferroelectricity, multiferroicity, superconductivity, pseudocapacitance, gas sensing, charge transport, and electrocatalytic properties. The formula of perovskite can be written as AA’BB’O6, when there is ordering between two cations over A and B-sites. Such compounds are called double perovskite oxides. Some amount of oxygen could be lost from crystal structure without decomposition of the phase. Such …

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Bovine Serum Albumin Detection By Using Molecularly Imprinted Surface Plasmon Resonance Sensors, Ali̇ Araz Jan 2022

Bovine Serum Albumin Detection By Using Molecularly Imprinted Surface Plasmon Resonance Sensors, Ali̇ Araz

Turkish Journal of Chemistry

Molecular imprinted polymers (MIP) have key-lock pattern binding properties specific to the size and shape of target molecules. In this study, we have prepared detection platforms based on a molecularly imprinted surface plasmon resonance (SPR) sensor that can detect bovine serum albumin (BSA) sensitively, selectively, quickly, and in real time. The polymeric film prepared on the SPR sensor surface by molecular imprinting method was obtained by selecting the N-methacryloyl-(L)-glutamic acid molecule as a suitable functional monomer using ultraviolet polymerization. Three different imprinting methods, such as epitope, bulk, and surface imprinting methods, were used to examine the imprinting efficiency. Real-time measurements …

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Polyvinyl Alcohol-Citrate-Stabilized Silver Nanoparticles As An Optical Sensor For Selective Colorimetric Determination Of Sildenafil, Asi̇ye Aslihan Avan Jan 2022

Polyvinyl Alcohol-Citrate-Stabilized Silver Nanoparticles As An Optical Sensor For Selective Colorimetric Determination Of Sildenafil, Asi̇ye Aslihan Avan

Turkish Journal of Chemistry

A facile and sensitive colorimetric detection method for sildenafil citrate (SLDC) has been developed by using polyvinyl alcohol-citrate-stabilized silver nanoparticles (PVA-Cit-AgNPs). The sensitivity and selectivity of colorimetric detection were investigated in detail. The PVA-Cit-AgNPs could be induced to aggregate immediately in the presence of SLDC, especially after the addition of 0.1 M HCl solution. The SLD could be detected by the colorimetric response of AgNPs that could be monitored by a UV-Vis spectrophotometer or even the naked eye. The linear range was found to be 0.6-5.0 μM with the calculated detection limit of 0.1 μM and the naked-eye detection limit …

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Electrochemistry Of Bubbles: Developing New Sensors, Promoting Gas Evolution Reactions, And Extraction Of Rare Earth Elements, Ruchiranga R. Ranaweera Jan 2022

Electrochemistry Of Bubbles: Developing New Sensors, Promoting Gas Evolution Reactions, And Extraction Of Rare Earth Elements, Ruchiranga R. Ranaweera

Wayne State University Dissertations

This dissertation presents new analytical, electrocatalysis, and separation strategies that utilize bubble behaviors in different electrochemical systems. The first part of this dissertation focuses on the method development for PFAS preconcentration and detection. First, we present the bubble-nucleation-based electrochemical method for the selective and sensitive detection of surfactants. Our method utilizes the high surface activity of surfactant analytes to affect the electrochemical bubble nucleation and then transduces the change in nucleation condition to an electrochemical signal for determining the surfactant concentration. Using this method, we demonstrate the quantitation of perfluorinated surfactants in water, a group of emerging environmental contaminants, with …

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Effects Of Localized Oxygen Production By Electrolysis On The First-Generation Glucose Sensor Response, Nandita Halder Dec 2021

Effects Of Localized Oxygen Production By Electrolysis On The First-Generation Glucose Sensor Response, Nandita Halder

Graduate Theses and Dissertations

Glucose sensors are very important for detecting blood glucose both in vitro and in vivo. First-generation glucose biosensors were based on the glucose oxidase (GOx) enzyme using molecular oxygen as the electron acceptor and therefore oxygen dependent. Unfortunately for in-vivo work, oxygen in the body is variable and limited. Alternative approaches to overcome the oxygen dependency came with their own limitations. The widely used and commercially available ex-vivo glucose test strip uses a mediator in place of oxygen to free it from oxygen dependency. The mediator-based technology, in most cases cannot be transferred to in vivo applications due to the …

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An Innovative Triboelectric Stent Sensor: Prospective Cardiovascular Health Monitor Device, Ulises Vidaurri Romero Dec 2021

An Innovative Triboelectric Stent Sensor: Prospective Cardiovascular Health Monitor Device, Ulises Vidaurri Romero

Theses and Dissertations

Previous research that has focused on TENGs have lacked the proper application of this energy generator. Currently, heart disease remains the leading cause of death in the United States. With increasing demand for self-sustainable medical devices, this nitinol health monitor sensor device (NHMS) integrates the TENG applications with medical applications. The NHMS features memory shape nitinol electrodes that preserves the device structure while using PDMS and PVDF triboelectric effect to measure heart rate, blood pressure, and breathing patterns. Three constant pressures were measured in this study. At a constant pressure of stage 1, the NHMS produces an average AC of …

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Knn Based Piezo-Triboelectric Lead-Free Hybrid Energy Films, Abu Masa Abdullah, Muhtasim Ul Karim Sadaf, Farzana Tasnim, Horacio Vasquez, Karen Lozano, M. Jasim Uddin Aug 2021

Knn Based Piezo-Triboelectric Lead-Free Hybrid Energy Films, Abu Masa Abdullah, Muhtasim Ul Karim Sadaf, Farzana Tasnim, Horacio Vasquez, Karen Lozano, M. Jasim Uddin

Chemistry Faculty Publications and Presentations

In recent times, the triboelectric and piezoelectric effects have garnered significant attention towards developing advanced material composites for energy harvesting and sensory applications. In this work, potassium sodium niobate (KNN) based energy films (EF) have been developed to utilize mechanical energy while simultaneously taking advantage of triboelectric and piezoelectric mechanisms. The KNN particles were synthesized using a wet ball milling technique and then incorporated into a polyvinylidene difluoride (PVDF) matrix together with addition of multi wall carbon nanotubes (MWCNT). The film was used to develop a piezoelectric nanogenerator (PENG) fitted with copper electrodes. The piezoelectric output of the film was …

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Ready-To-Wear Strain Sensing Gloves For Human Motion Sensing, Sara S. Mechael, Yunyun Wu, Yiting Chen, Tricia Breen Carmichael Jun 2021

Ready-To-Wear Strain Sensing Gloves For Human Motion Sensing, Sara S. Mechael, Yunyun Wu, Yiting Chen, Tricia Breen Carmichael

Chemistry and Biochemistry Publications

Integrating soft sensors with wearable platforms is critical for sensor-based human augmentation, yet the fabrication of wearable sensors integrated into ready-to-wear platforms remains underdeveloped. Disposable gloves are an ideal substrate for wearable sensors that map hand-specific gestures. Here, we use solution-based metallization to prepare resistive sensing arrays directly on off-the-shelf nitrile butadiene rubber (NBR) gloves. The NBR glove acts as the wearable platform while its surface roughness enhances the sensitivity of the overlying sensing array. The NBR sensors have a sheet resistance of 3.1 ± 0.6 Ω/sq and a large linear working range (two linear regions ≤70%). When stretched, the …

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Collisions Or Adsorption: An Electrochemical Random Walk Decides, Junaid U. Ahmed, Julio C. Alvarez Jan 2021

Collisions Or Adsorption: An Electrochemical Random Walk Decides, Junaid U. Ahmed, Julio C. Alvarez

Graduate Research Posters

Current-time recordings of toluene microdroplets emulsified in water and containing 20 mM Ferrocene (Fc), show multiple electrochemical peaks from oxidation of Fc on disk microelectrodes (5μm-diameter). The average droplet diameter (~0.7 μm) determined from area integration of the peaks was close to Dynamic Light Scattering measurements (~1 μm). Random walk simulations were performed deriving equations to simulate droplet electrolysis using the diffusion and thermal velocity expressions established by Einstein. The simulations show that multiple droplet-electrode collisions, lasting ~0.11 μs each, occur before a droplet wanders away. Updating the Fc-concentration at every collision shows that a droplet only oxidizes ~0.58 % …

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Puerarin-Coated Gold Nanoparticles (Pue-Aunps) Synthesized Via Green Synthetic Route: A New Colorimetric Probe For The Detection Of Ciprofloxacin, Tasneem Zehra, Faiqa Ahsan, Muhammad Ali Versiani, Sana Wahid, Sajid Jahangir, Muhammad Raza Shah Jan 2021

Puerarin-Coated Gold Nanoparticles (Pue-Aunps) Synthesized Via Green Synthetic Route: A New Colorimetric Probe For The Detection Of Ciprofloxacin, Tasneem Zehra, Faiqa Ahsan, Muhammad Ali Versiani, Sana Wahid, Sajid Jahangir, Muhammad Raza Shah

Turkish Journal of Chemistry

Puerarin-coated gold nanoparticles (PUE-AuNPs) synthesized via green synthetic route, a new colorimetric sensor, efficiently detected the ciprofloxacin (CP) in tap water and cow milk samples. The PUE-AuNPs were characterized by UV-visible, FTIR, AFM, and DLS techniques and were found to be spherical with an average size of approximately 19-20 nm. FTIR spectrum confirms that functional groups such as -OH, -C=O, -CO and -C=C were responsible for the reduction of gold (III) chloride trihydrate. These functional groups acted as capping agents to form AuNPs. The PUE-AuNPs sensor was proved to be selective and sensitive for the detection of CP through colorimetric …

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Conversion From Metal Oxide To Mof Thin Films As A Platform Of Chemical Sensing, Meng Chen Nov 2020

Conversion From Metal Oxide To Mof Thin Films As A Platform Of Chemical Sensing, Meng Chen

USF Tampa Graduate Theses and Dissertations

Chemical sensor is working as a widely used device which can be applied to the detection of specific chemicals that are existing in the environment especially in gas phase. The detection of combustible and toxic chemicals can be extremely important in the field of both industrial and civil activities. The chemical sensor is commonly operating by utilizing a chemical or physical interaction between the specific chemical compound and the sensing functional unit, to obtain an electronic signal caused by the property change and realize the chemical detection. Traditional chemical gas sensors such as catalytic gas sensor, thermal conductivity gas sensor, …

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Response Of Photoluminescence Of H-Terminated And Hydrosilylated Porous Si Powders To Rinsing And Temperature, Kurt W. Kolasinski, Joseph D. Swanson, Benjamin Roe, Teresa Lee Aug 2020

Response Of Photoluminescence Of H-Terminated And Hydrosilylated Porous Si Powders To Rinsing And Temperature, Kurt W. Kolasinski, Joseph D. Swanson, Benjamin Roe, Teresa Lee

Chemistry Faculty Publications

The photoluminescence (PL) response of porous Si has potential applications in a number of sensor and bioimaging techniques. However, many questions still remain regarding how to stabilize and enhance the PL signal, as well as how PL responds to environmental factors. Regenerative electroless etching (ReEtching) was used to produce photoluminescent porous Si directly from Si powder. As etched, the material was H-terminated. The intensity and peak wavelength were greatly aected by the rinsing protocol employed. The highest intensity and bluest PL were obtained when dilute HCl(aq) rinsing was followed by pentane wetting and vacuum oven drying. Roughly half of the …

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A Simple And Sensitive Aptamer-Based Electrochmical Sensor For Determination Of Aflatoxin B1, Bing Liu, Yao-Shuai Zhao, Yue Qin, Yi Wang, Yan-Jie Zhu, Shuo Wang Jun 2020

A Simple And Sensitive Aptamer-Based Electrochmical Sensor For Determination Of Aflatoxin B1, Bing Liu, Yao-Shuai Zhao, Yue Qin, Yi Wang, Yan-Jie Zhu, Shuo Wang

Journal of Electrochemistry

Aflatoxin B1 has attracted much attention because of its high toxicity and carcinogenicity, which has become a great concern in food safety. Based on the principle of specific binding between Aflatoxin B1 and its aptamer, an aptamer-based electrochemical sensor had been designed and developed for the determination of minor Aflatoxin B1 contained in grain. The mesoporous carbons were first modified on the surface of the working electrode, and then the gold nanoparticles were on-site electrodeposited at a constant potential. Each modified electrode was characteritised by scanning electron microscopy (SEM) and electrochemical impedance spectroscopy (EIS). As a result, the surface area …

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Chitosan Curcumin Film As A Sensor For Detection Of O-Nitrophenol And Fluoride Ion Using Fluoresce Quenching Technique, Soma Chakraborty, Andrea Paola D. Ilagan Mar 2020

Chitosan Curcumin Film As A Sensor For Detection Of O-Nitrophenol And Fluoride Ion Using Fluoresce Quenching Technique, Soma Chakraborty, Andrea Paola D. Ilagan

Chemistry Faculty Publications

Curcumin was immobilized in chitosan films fabricated by solvent casting method. The amount of curcumin immobilization was more when methanol was used as a solvent to dissolve curcumin than the butanol solvent. The maximum amount of curcumin immobilized per gram of chitosan film was 0.023 g. Immobilized curcumin was not released back in water even after prolong contact of the films with water. Fluorescence intensity of the films got quenched when these films were in contact with an aqueous solution of o-nitrophenol (ONP) and sodium fluoride (NaF). The extent of quenching depended on the concentration of these attributes. Fluorescence intensity …

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Design, Construction, And Characterization Of A Combined Mini-Co₂/Voc Sensor And Gas Chromatograph For Field Research, Rishi Basdeo, Michael Hampton Jan 2020

Design, Construction, And Characterization Of A Combined Mini-Co₂/Voc Sensor And Gas Chromatograph For Field Research, Rishi Basdeo, Michael Hampton

Digital Repository: Showcase of Undergraduate Research Excellence

No abstract provided.

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Application Of Synthesized Copper Nanoparticles Using Aqueous Extract Ofziziphus Mauritiana L. Leaves As A Colorimetric Sensor For The Detection Of Ag$^{+}$, Roomia Memon, Ayaz Ali Memon, Syed Tufail Hussain Sherazi, Siraj Uddin, Aamna Balouch, Muhammad Raza Shah, Sarfaraz Ahmed Mahesar, Kauser Rajar, Muhammad Hassan Agheem Jan 2020

Application Of Synthesized Copper Nanoparticles Using Aqueous Extract Ofziziphus Mauritiana L. Leaves As A Colorimetric Sensor For The Detection Of Ag$^{+}$, Roomia Memon, Ayaz Ali Memon, Syed Tufail Hussain Sherazi, Siraj Uddin, Aamna Balouch, Muhammad Raza Shah, Sarfaraz Ahmed Mahesar, Kauser Rajar, Muhammad Hassan Agheem

Turkish Journal of Chemistry

The presented work demonstrates the preparation of copper nanoparticles (CuNPs) via aqueous leaves extract of Ziziphus mauritiana L. (Zm) using hydrazine as a reducing agent. Various parameters such as volume of extract, concentration of hydrazine hydrate, concentration of copper chloride, and pH of the solution were optimized to obtain Ziziphus mauritiana L. leaves extract derived copper nanoparticles (Zm-CuNPs). Brownish red color was initial indication of the formation of Zm-CuNPs while it was confirmed by surface plasmon resonance (SPR) band at wavelength of 584 nm using ultraviolet-visible (UV-vis) spectroscopy. Synthesized Zm-CuNPs were characterized by Fourier transform infrared spectroscopy (FT-IR), scanning electron …

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Development Of Analytical Methods For Toxic Inhaled Hazards (Tih) And Their Metabolites, Obed Adu Gyamfi Jan 2020

Development Of Analytical Methods For Toxic Inhaled Hazards (Tih) And Their Metabolites, Obed Adu Gyamfi

Electronic Theses and Dissertations

Toxic inhalation hazards (TIHs), such as methyl isocyanate (MIC) and hydrogen cyanide (HCN), are noxious gases and vapors that are harmful, and often deadly, to humans. However, because of their low cost and high reactivity, they are extensively used for industrial productions, creating risk of exposure for both industrial workers (e.g., occupational exposure) and civilians (e.g., accidental release during transport). The illicit use of TIHs, including as terrorist agents, is also concerning. Considering the rapid toxicity of TIHs and the danger they pose to both human and animal lives, there is a critical need to develop of analytical methods for …

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Colorimetric Cadmium Ion Detection In Aqueous Solutions By Newly Synthesized Schiff Bases, Zi̇ya Aydin, Mustafa Keleş Jan 2020

Colorimetric Cadmium Ion Detection In Aqueous Solutions By Newly Synthesized Schiff Bases, Zi̇ya Aydin, Mustafa Keleş

Turkish Journal of Chemistry

Two newly synthesized Schiff bases DMCA and DMBA were used for selective detection of Cd$^{2+}$ over a wide range of other metal ions in acetonitrile (ACN)/ Tris-HCl buffer (10 mM, pH 7.32, v/v 2:1). The sensors can detect Cd$^{2+}$ ions by colour changes from colourless to orange for DMBA and yellow to reddish for DMCA. Response of the probes towards metal ions was investigated by using UV-vis spectroscopy. The complex stoichiometry between the sensors, DMBA and DMCA, and Cd$^{2+}$ was found to be 2:1 and the binding constants were calculated to be 2.65 x 10$^{12}$ M$^{-2\, }$and 4.95 x 10$^{12}$ …

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Turn-On Near-Infrared Fluorescent Sensors For Selective Monitoring Of Kinase Activity, Gerard Thomas Ducharme Oct 2019

Turn-On Near-Infrared Fluorescent Sensors For Selective Monitoring Of Kinase Activity, Gerard Thomas Ducharme

LSU Doctoral Dissertations

Reliable and selective detection of specific biopolymers is critical in a broad range of biomedical and technological areas, including availability of simple and efficient point-of-care-compatible systems for the detection of prognostic, pharmacodynamic and predictive biomarkers. Monitoring epidermal growth factor receptor (EGFR) tyrosine kinase is of major significance due to its link to many epithelial cancers. This task is complicated by the high rate of mutation occurring in patients treated with kinase inhibitors. This dissertation describes a conceptually novel design and synthesis of turn-on near-infrared fluorescent sensors for selective and sensitive detection of EGFR. The fluorescent signal generation mechanism is based …

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Organic-Inorganic Hybrid Materials For Piezoelectric/Triboelectric Nanogenerator, Aminur Rashid Chowdhury Aug 2019

Organic-Inorganic Hybrid Materials For Piezoelectric/Triboelectric Nanogenerator, Aminur Rashid Chowdhury

Theses and Dissertations

Nanogenerator has been a major focus among researchers of recent time due to its versatile use in everyday life. Though the discovery of the piezoelectricity and the triboelectricity dates back to 19th century, the use of these phenomena has not been in practical use till 2006. In this study we demonstrate the practical application of piezoelectric and triboelectric nanogenerator comprised of different copolymer and piezoelectric ceramic. The largely known piezoelectric polymer Polyvinylidene fluoride (PVDF) has also been utilized. The enhancement of piezoelectric properties of PVDF has been achieved by utilizing surface activation of accommodating ceramic. The Li doped ZnO has …

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