Relevant bibliographies by topics / Formaldehyde sensors

Academic literature on the topic 'Formaldehyde sensors'

Author: Grafiati
Published: 10 December 2022
Last updated: 29 January 2023

Create a spot-on reference in APA, MLA, Chicago, Harvard, and other styles

Select a source type:

Contents

Consult the lists of relevant articles, books, theses, conference reports, and other scholarly sources on the topic 'Formaldehyde sensors.'

Next to every source in the list of references, there is an 'Add to bibliography' button. Press on it, and we will generate automatically the bibliographic reference to the chosen work in the citation style you need: APA, MLA, Harvard, Chicago, Vancouver, etc.

You can also download the full text of the academic publication as pdf and read online its abstract whenever available in the metadata.

Journal articles on the topic "Formaldehyde sensors"

1

Wang, Jing, Xing Ru Chen, Peng Jun Yao, Min Ji, Jin Qing Qi, and Wei Wu. "Detection of Indoor Formaldehyde Concentration Using LaSrFeO3-Doped SnO2 Gas Sensor." Key Engineering Materials 437 (May 2010): 349–53. http://dx.doi.org/10.4028/www.scientific.net/kem.437.349.

Full text
Abstract:
Formaldehyde gas sensors with a structure of ceramic tube were fabricated by using La0.8Sr0.2FeO3-doped nanometer tin oxide. The highest response to formaldehyde appeared when the heating temperature of the La0.8Sr0.2FeO3-doped SnO2 sensor was about 370 °C. The response of the sensors to formaldehyde was measured in a gas concentration in the range of 0 - 5 ppm. The lowest formaldehyde concentration detected by 2 wt % (weight ratio) of La0.8Sr0.2FeO3-doped SnO2 gas sensor was 0.05 ppm. The response and recover times of the sensor to 0.5 ppm formaldehyde were about 120 s and 100 s, respectively. The response of the sensor to some interferent gases was tested.
APA, Harvard, Vancouver, ISO, and other styles
2

Arabi, Mohamed, Majed Alghamdi, Khalid Kabel, Ahmed Labena, Walaa S. Gado, Bhoomi Mavani, Alison J. Scott, Alexander Penlidis, Mustafa Yavuz, and Eihab Abdel-Rahman. "Detection of Volatile Organic Compounds by Using MEMS Sensors." Sensors 22, no. 11 (May 28, 2022): 4102. http://dx.doi.org/10.3390/s22114102.

Full text
Abstract:
We report on the deployment of MEMS static bifurcation (DC) sensors for the detection of volatile organic compounds (VOCs): hydrogen sulfide and formaldehyde. We demonstrate a sensor that can detect as low as a few ppm of hydrogen sulfide. We also demonstrate a sensor array that can selectively detect formaldehyde in the presence of benzene, a closely related interferent. Toward that end, we investigate the sensitivity and selectivity of two detector polymers—polyaniline (PANI) and poly (2,5-dimethyl aniline) (P25DMA)—to both gases. A semiautomatic method is developed to functionalize individual sensors and sensor arrays with the detector polymers. We found that the sensor array can selectively sense 1 ppm of formaldehyde in the presence of benzene.
APA, Harvard, Vancouver, ISO, and other styles
3

He, Ying Fei, Ya Dong Jiang, Hui Ling Tai, and Guang Zhong Xie. "The Investigation of Quartz Crystal Microbalance (QCM) Formaldehyde Sensors Based on PEI-MWCNTs Composites." Advanced Materials Research 1030-1032 (September 2014): 217–22. http://dx.doi.org/10.4028/www.scientific.net/amr.1030-1032.217.

Full text
Abstract:
The detection of formaldehyde is very necessary and important in both industrial and residential environments. In this paper, a novel quartz crystal microbalances (QCM) formaldehyde gas sensor has been successful fabricated based on Polyethylenimine (PEI)-multi-walled carbon nanotubes (MWCNTs) composite films by the spraying process. The morphology of films was analyzed by scanning electron microscope (SEM), and formaldehyde-sensing properties of sensors were investigated. The results showed that the prepared QCM gas sensor exhibited good response and recovery behaviors towards formaldehyde gas in the concentration range of 0-10 ppm at room temperature, which also has the superior repeatability and selectivity. Moreover, the gas-sensing mechanism of sensors was studied.
APA, Harvard, Vancouver, ISO, and other styles
4

He, Ying Fei, Ya Dong Jiang, Hui Ling Tai, and Guang Zhong Xie. "Fabrication and Formaldehyde-Sensing Property of Quartz Crystal Microbalance (QCM) Coated with PVP-MWCNTs Composites." Key Engineering Materials 645-646 (May 2015): 719–23. http://dx.doi.org/10.4028/www.scientific.net/kem.645-646.719.

Full text
Abstract:
In this paper, the quartz crystal microbalance (QCM) sensors coated with polyvinyl pyrrolidone (PVP)-multiwalled carbon nanotubes (MCWNTs) nanocomposite thin films were developed by the spray process, which were used for the detection of low concentration formaldehyde at room temperature. The surface morphology and structure of films was analyzed by scanning electron microscope (SEM), UV-Vis absorption spectrometry, respectively, and the formaldehyde-sensing properties of sensors were investigated. The results showed that the prepared QCM gas sensor exhibited the linear characteristic, fast response, good reproducibility to low concentration formaldehyde within 6 ppm, and the poisoning of films was observed when the formaldehyde concentration exceeded 6ppm. Moreover, the sensitivity of the sensor could achieve up to 1Hz/ppm and had the good stability of response values.
APA, Harvard, Vancouver, ISO, and other styles
5

Park, Jae Jung, Yongsoo Kim, Chanmin Lee, Jun-Won Kook, Donghyun Kim, Jung-Hyun Kim, Ki-Seob Hwang, and Jun-Young Lee. "Colorimetric Visualization Using Polymeric Core–Shell Nanoparticles: Enhanced Sensitivity for Formaldehyde Gas Sensors." Polymers 12, no. 5 (April 25, 2020): 998. http://dx.doi.org/10.3390/polym12050998.

Full text
Abstract:
Although equipment-based gas sensor systems (e.g., high-performance liquid chromatography) have been widely applied for formaldehyde gas detection, pre-treatment and expensive instrumentation are required. To overcome these disadvantages, we developed a colorimetric sensor based on polymer-based core–shell nanoparticles (PCSNPs), which are inexpensive, stable, and exhibit enhanced selectivity. Spherical and uniform poly(styrene-co-maleic anhydride) (PSMA)/polyethyleneimine (PEI) core–shell nanoparticles were prepared and then impregnated with Methyl Red (MR), Bromocresol Purple (BCP), or 4-nitrophenol (4-NP) to construct colorimetric sensors for formaldehyde gas. The intrinsic properties of these dyes were maintained when introduced into the PCSNPs. In the presence of formaldehyde, the MR, BCP, and 4-NP colorimetric sensors changed to yellow, red, and gray, respectively. The colorimetric response was maximized at a PEI/PSMA ratio of four, likely owing to the high content of amine groups. Effective formaldehyde gas detection was achieved at a relative humidity of 30% using the MR colorimetric sensor, which exhibited a large color change (92%) in 1 min. Advantageously, this stable sensor allowed sensitive and rapid naked-eye detection of low formaldehyde concentrations (0.5 ppm). Hence, this approach is promising for real-time formaldehyde gas visualization and can also be adapted to other colorimetric gas sensor systems to improve sensitivity and simplicity.
APA, Harvard, Vancouver, ISO, and other styles
6

Chobsilp, Thanattha, Thotsaphon Threrujirapapong, Visittapong Yordsri, Alongkot Treetong, Saowaluk Inpaeng, Karaked Tedsree, Paola Ayala, Thomas Pichler, Lei Shi, and Worawut Muangrat. "Highly Sensitive and Selective Formaldehyde Gas Sensors Based on Polyvinylpyrrolidone/Nitrogen-Doped Double-Walled Carbon Nanotubes." Sensors 22, no. 23 (November 30, 2022): 9329. http://dx.doi.org/10.3390/s22239329.

Full text
Abstract:
A highly sensitive and selective formaldehyde sensor was successfully fabricated using hybrid materials of nitrogen-doped double-walled carbon nanotubes (N-DWCNTs) and polyvinylpyrrolidone (PVP). Double-walled carbon nanotubes (DWCNTs) and N-DWCNTs were produced by high-vacuum chemical vapor deposition using ethanol and benzylamine, respectively. Purified DWCNTs and N-DWCNTs were dropped separately onto the sensing substrate. PVP was then dropped onto pre-dropped DWCNT and N-DWCNTs (hereafter referred to as PVP/DWCNTs and PVP/N-DWCNTs, respectively). As-fabricated sensors were used to find 1,2-dichloroethane, dichloromethane, formaldehyde and toluene vapors in parts per million (ppm) at room temperature for detection measurement. The sensor response of N-DWCNTs, PVP/DWCNTs and PVP/N-DWCNTs sensors show a high response to formaldehyde but a low response to 1,2-dichloroethane, dichloromethane and toluene. Remarkably, PVP/N-DWCNTs sensors respond sensitively and selectively towards formaldehyde vapor, which is 15 times higher than when using DWCNTs sensors. This improvement could be attributed to the synergistic effect of the polymer swelling and nitrogen-sites in the N-DWCNTs. The limit of detection (LOD) of PVP/N-DWCNTs was 15 ppm, which is 34-fold higher than when using DWCNTs with a LOD of 506 ppm. This study demonstrated the high sensitivity and selectivity for formaldehyde-sensing applications of high-performance PVP/N-DWCNTs hybrid materials.
APA, Harvard, Vancouver, ISO, and other styles
7

Flueckiger, Jonas, Frank Ko, and Karen Cheung. "Microfabricated Formaldehyde Gas Sensors." Sensors 9, no. 11 (November 18, 2009): 9196–215. http://dx.doi.org/10.3390/s91109196.

Full text
APA, Harvard, Vancouver, ISO, and other styles
8

Merenkova, A. A., K. V. Zhuzhukin, A. N. Zyablov, and L. I. Belchinskaya. "Determination of formaldehyde in production solutions using the piezoelectric sensors." Аналитика и контроль 25, no. 2 (2021): 140–45. http://dx.doi.org/10.15826/analitika.2021.25.2.003.

Full text
Abstract:
In the current work, piezoelectric sensors based on a molecular imprinted polymer (MIP) were obtained for determining the formaldehyde in the industrial solutions of a woodworking plant. The synthesis was carried out directly on the surface of the piezoelectric sensor. In the process of the two-stage thermoimidization of the obtained prepolymerization mixture, a molecular imprinted polyimide of formaldehyde was formed. For the analysis of the supra-resin part of the effluent of the Grafskaya kuhnya LLC (Voronezh) woodworking enterprise, which was obtained by the dry distillation of wood, the method of a calibration graph having a linear relationship was used; the coefficient of determination R2 = 0.97. The detection limit of the piezosensor was 0.6 ∙ 10–4 mol / dm3, the range of determined concentrations was 1.0 – 10–4 mol / dm3. The comparison of piezoelectric sensors based on the polymer without imprints and based on the polymer with imprints of formaldehyde showed high selectivity of the latter for the target molecule. The calculated imprinting factor was 28.3, the coefficient of selectivity with respect to phenol was 0.05, which indicated the selectivity of the modified sensor to formaldehyde. The verification of the correctness of the determination of formaldehyde in the model and production solutions was carried out using the "added-found" method. It was found that the MIP-based sensor was sensitive only to formaldehyde, the relative standard deviation did not exceed 2.0%. In order to assess the effect of the object matrix (formaldehyde) on the value of the resonant frequency, the standard addition method was used. It was determined that the matrix did not affect the value of the analytical signal, the relative standard deviation was 2.8%. For the re-analysis, the piezoelectric sensor was exposed to the regeneration in the oven at 50 ⁰С. The proposed method for determining the concentration of the formaldehyde using the MIP-sensor allowed controlling the content of the toxicant in the industrial solutions.
APA, Harvard, Vancouver, ISO, and other styles
9

A. Akbar, S., A. Mardhiah, N. Saidi, and D. Lelifajri. "The effect of graphite composition on polyaniline film performance for formalin gas sensor." Bulletin of the Chemical Society of Ethiopia 34, no. 3 (January 12, 2021): 597–604. http://dx.doi.org/10.4314/bcse.v34i3.14.

Full text
Abstract:
The invention of formalin gas sensors based on polyaniline (PANI) has been developed which arranged by PANI|graphite composite form. The reaction between amine and formaldehyde produced a Schiff base that alters the resistance of PANI film as a function of formaldehyde concentration. The response of the sensor was measured in variations of graphite composition with 3%, 10%, and 25%. The results showed similar patterns in all concentrations of formalin. However, the sensor response at 10% and 25% graphite decreased dramatically. The formalin with concentration 400 ppm shown the response with 3% graphite was 1.62 times greater than 25%. Addition of too much graphite makes the absorption area on the PANI surface becomes less because the graphite covered it. In this case, the sensor performance was still stable and functional, but the measured resistance seems smaller because the sensor conductivity level more dominated by graphite. Therefore, composites of polyaniline and graphite can be used as sensors to detect the presence of formaldehyde gas. KEY WORDS: Formalin, Graphite, Polyaniline, Resistance, Sensors Bull. Chem. Soc. Ethiop. 2020, 34(3), 597-604. DOI: https://dx.doi.org/10.4314/bcse.v34i3.14
APA, Harvard, Vancouver, ISO, and other styles
10

Yuan, Zhenyu, Chang Yang, and Fanli Meng. "Strategies for Improving the Sensing Performance of Semiconductor Gas Sensors for High-Performance Formaldehyde Detection: A Review." Chemosensors 9, no. 7 (July 14, 2021): 179. http://dx.doi.org/10.3390/chemosensors9070179.

Full text
Abstract:
Formaldehyde is a poisonous and harmful gas, which is ubiquitous in our daily life. Long-term exposure to formaldehyde harms human body functions; therefore, it is urgent to fabricate sensors for the real-time monitoring of formaldehyde concentrations. Metal oxide semiconductor (MOS) gas sensors is favored by researchers as a result of their low cost, simple operation and portability. In this paper, the mechanism of formaldehyde detection by gas sensors is introduced, and then the ways of ameliorating the response of gas sensors for formaldehyde detection in recent years are summarized. These methods include the control of the microstructure and morphology of sensing materials, the doping modification of matrix materials, the development of new semiconductor sensing materials, the outfield control strategy and the construction of the filter membrane. These five methods will provide a good prerequisite for the preparation of better performing formaldehyde gas sensors.
APA, Harvard, Vancouver, ISO, and other styles
More sources

Dissertations / Theses on the topic "Formaldehyde sensors"

1

Boddeti, Ravi Kumar. "Laser spectroscopy sensors for measurement of trace gaseous formaldehyde /." Connect to resource online, 2008. http://rave.ohiolink.edu/etdc/view?acc_num=ysu1220624621.

Full text
APA, Harvard, Vancouver, ISO, and other styles
2

Boddeti, Ravi K. "Laser Spectroscopy Sensors for Measurement of Trace Gaseous Formaldehyde." Youngstown State University / OhioLINK, 2008. http://rave.ohiolink.edu/etdc/view?acc_num=ysu1220624621.

Full text
APA, Harvard, Vancouver, ISO, and other styles
3

De, Smedt Isabelle. "Long-term global observations of tropospheric formaldehyde retrieved from spaceborne nadir UV sensors." Doctoral thesis, Universite Libre de Bruxelles, 2011. http://hdl.handle.net/2013/ULB-DIPOT:oai:dipot.ulb.ac.be:2013/209919.

Full text
Abstract:
Atmospheric formaldehyde (H2CO) is an intermediate product common to the degradation of many volatile organic compounds and therefore it is a central component of the tropospheric chemistry. While the global formaldehyde background is due to methane oxidation, emissions of non-methane volatile organic compounds (NMVOCs) from biogenic, biomass burning and anthropogenic continental sources result in important and localised enhancements of the H2CO concentration. Recent spaceborne nadir sensors provide an opportunity to quantify the abundance of tropospheric formaldehyde at the global scale, and thereby to improve our knowledge of NMVOC emissions. This is essential for a better understanding of the processes that control the production and the evolution of tropospheric ozone, a key actor in air quality and climate change, but also of the hydroxyl radical OH, the main cleansing agent of our troposphere. For this reason, H2CO satellite observations are increasingly used in combination with tropospheric chemistry transport models to constrain NMVOC emission inventories in so-called top-down inversion approaches. Such inverse modelling applications require well characterised satellite data products consistently retrieved over long time periods.

This work reports on global observations of formaldehyde columns retrieved from the successive solar backscatter nadir sensors GOME, SCIAMACHY and GOME-2, respectively launched in 1995, 2002 and 2006. The retrieval procedure is based on the differential optical absorption spectroscopy technique (DOAS). Formaldehyde concentrations integrated along the mean atmospheric optical path are derived from the recorded spectra in the UV region, and further converted to vertical columns by means of calculated air mass factors. These are obtained from radiative transfer simulations, accounting for cloud coverage, surface properties and best-guess H2CO profiles, the latter being derived from the IMAGES chemistry transport model. A key task of the thesis has consisted in the optimisation of the H2CO retrieval settings from multiple sensors, taking into account the instrumental specificities of each sounder. As a result of these efforts, a homogeneous dataset of formaldehyde columns covering the period from 1996 to 2010 has been created. This comes with a comprehensive error budget that treats errors related to the spectral fit of the columns as well as those associated to the air mass factor evaluation. The time series of the GOME, SCIAMACHY and GOME-2 H2CO observations is shown to be consistent and stable over time. In addition, GOME-2 brings a significant reduction of the noise on spatiotemporally averaged observations, leading to a better identification of the emission sources. Our dataset is used to study the regional formaldehyde distribution, as well as its seasonal and interannual variations, principally related to temperature changes and fire events, but also to anthropogenic activities. Moreover, building on the quality of our 15-year time series, we present the first analysis of long-term changes in the H2CO columns. Positive trends, in the range of 1.5 to 4% yr-1, are found in Asia, more particularly in Eastern China and India, and are related to the known increase of anthropogenic NMVOC emissions in these regions. Finally, our dataset has been extensively used in several studies, in particular by the BIRA-IASB modelling team to constrain NMVOC emission fluxes. The results demonstrate the high potential of satellite data as top-down constraint for biogenic and biomass burning NMVOC emission inventories, especially in Tropical ecosystems, in Southeastern Asia, and in Southeastern US.

Le formaldéhyde (H2CO) joue un rôle central dans la chimie de la troposphère en tant que produit intermédiaire commun à la dégradation chimique de la plupart des composés organiques volatils dans l’atmosphère. L’oxydation du méthane est responsable de plus de la moitié de la concentration moyenne globale du formaldéhyde. Sur les continents en revanche, les hydrocarbures non-méthaniques (NMVOCs) émis par la végétation, les feux de biomasse et les activités humaines, augmentent de façon significative et localisée la concentration de H2CO. Les récents senseurs satellitaires à visée nadir offrent la possibilité de quantifier à l’échelle globale l’abondance du formaldéhyde dans la troposphère et de ce fait, d’améliorer notre connaissance des émissions de NMVOCs. Ceci est essentiel à la compréhension des mécanismes contrôlant la production et l’évolution de l’ozone troposphérique, élément clé pour la qualité de l’air et les changements climatiques, mais aussi du composé hydroxyle OH, le principal agent nettoyant de notre troposphère. C’est pourquoi, une méthode de plus en plus répandue pour améliorer les inventaires d’émissions des NMVOCs consiste en l’utilisation d’observations satellitaires de H2CO en combinaison avec un modèle de chimie et de transport troposphérique, dans une approche appelée modélisation inverse. Ce genre d’application demande des produits satellitaires bien caractérisés et dérivés de façon cohérente sur de longues périodes de temps.

Le travail présenté dans ce manuscrit porte sur l’inversion des colonnes de formaldéhyde à partir de spectres de la radiation solaire rétrodiffusée par l’atmosphère terrestre, mesurés par les senseurs GOME, SCIAMACHY et GOME-2, lancés successivement en 1995, 2002 et 2006. La méthode d’inversion est basée sur la spectroscopie d’absorption optique différentielle (DOAS). Les concentrations de formaldéhyde intégrées le long du chemin optique moyen dans l’atmosphère sont dérivées à partir des spectres mesurés, et ensuite transformées en colonnes verticales par le biais de facteurs de conversion appelés facteurs de masse d’air. Ces derniers sont calculés à l’aide d’un modèle de transfert radiatif, en tenant compte de la présence de nuages, des propriétés de la surface terrestre et la distribution verticale supposée du formaldéhyde, fournie par le modèle IMAGES. Un des objectifs principaux de la thèse a été d’optimiser les paramètres d’inversion pour H2CO, et ceci pour les trois senseurs, tout en tenant compte des spécificités de chaque instrument. Ces efforts ont conduit à la création d’un jeu de données homogène, couvrant la période de 1996 à 2010. Les colonnes sont fournies avec un bilan d’erreur complet, incluant les erreurs liées à l’inversion des concentrations dans les spectres, ainsi que celles provenant de l’évaluation des facteurs de masse d’air. La série temporelle des observations de GOME, SCIAMACHY et GOME-2 présente une bonne cohérence et stabilité sur toute la période. Nous montrons aussi que la meilleure couverture terrestre de GOME-2 entraîne une réduction significative du bruit sur les observations moyennées, permettant une meilleure identification des sources d’émission. Notre jeu de données est exploité pour étudier la distribution régionale du formaldéhyde, ainsi que ses variations saisonnières et interannuelles, principalement liées aux variations de température et aux feux de végétation, mais aussi aux activités anthropiques. De plus, en s’appuyant sur la qualité de la série temporelle de 15 ans, nous présentons la première analyse des variations à long terme des concentrations de H2CO. Des tendances positives, de l’ordre de 1.5 à 4% par an, sont observées en Asie, en particulier dans l’est de la Chine et en Inde, liées à l’augmentation des émissions anthropiques d’hydrocarbures dans ces régions. Finalement, nos données ont été largement exploitées par le groupe de modélisation de l’IASB pour faire des études de modélisation inverse des émissions de NMVOCs. Les résultats démontrent le haut potentiel des données satellitaires pour contraindre les inventaires d’émissions dues à la végétation et aux feux de biomasse, particulièrement dans les écosystèmes tropicaux, en Asie du sud-est, et dans le sud-est des Etats-Unis.
Doctorat en Sciences de l'ingénieur
info:eu-repo/semantics/nonPublished

APA, Harvard, Vancouver, ISO, and other styles
4

Alolaywi, Haidar. "Electrochemical MoOx/Carbon Nanocomposite Gas Sensor for Formaldehyde Detection at Room Temperature." University of Toledo / OhioLINK, 2020. http://rave.ohiolink.edu/etdc/view?acc_num=toledo1596821142716346.

Full text
APA, Harvard, Vancouver, ISO, and other styles
5

Ravi, Srivathsan. "Continuous Monitoring and Removal of Formaldehyde Vapor in Ambient Air Using Polymer Catalyst Membranes." University of Cincinnati / OhioLINK, 2013. http://rave.ohiolink.edu/etdc/view?acc_num=ucin1384428049.

Full text
APA, Harvard, Vancouver, ISO, and other styles
6

Cuba, Supanta Gustavo. "Efectos del dopaje y la temperatura sobre las propiedades térmicas de hetero-estructuras de C/BN y su potencial uso como sensor ambiental del formaldehído." Doctoral thesis, Universidad Nacional Mayor de San Marcos, 2019. https://hdl.handle.net/20.500.12672/12312.

Full text
Abstract:
Se estudia la influencia del dopaje y de la temperatura sobre las propiedades físicas de hetero-estructuras hexagonales principalmente basadas en carbono y nitruro de boro tanto uni- y bi-dimensionales, este estudio se divide en tres partes. Por un lado, se estudia el efecto del dopaje de nitruro de boro en nanotubos de carbono armchair (6, 6) (hetero-nanotubos de nitruro de boro y carbono) sobre las propiedades del transporte cuántico de fonones y electrones, variando patrones de distribución y concentración de dopaje. Por otro lado, se estudia la forma como afecta la temperatura del sustrato sobre las propiedades del transporte térmico clásico en hetero-nanocintas de grafeno/nitruro de boro hexagonal y nitruro de boro hexagonal/grafeno, e influenciados por la asimetría estructural. Análogamente, también se estudia el efecto de la temperatura media y bias en hetero-nanocintas de grafeno/X (X=nitruro de boro hexagonal, carburo de silicio hexagonal, y grafeno hidrogenado), afectados por dos tipos de interfaces (zigzag y armchair). Por último, se estudia las propiedades electrónicas del proceso de adsorción de la molécula del Formaldehído (CH2O) sobre el sustrato de nitruro de boro hexagonal hidrogenado. Para ello, la metodología empleada en estos trabajos consistió en el uso de tres métodos computacionales; las funciones de Green fuera del equilibrio (NEGF) en combinación con el método de la teoría del funcional de la densidad basado en tight-binding (DFTB), dinámica molecular fuera del equilibrio (NEMD), y cálculos de la teoría del funcional de la densidad, respectivamente. Por un lado, los resultados respecto al efecto del dopaje sobre el transporte cuántico muestran que al aumentar la concentración del dopaje en los hetero-nanotubos de nitruro de boro y carbono armchair (6, 6), los coeficiente de transmisión fonónico y electrónico se reducen, este comportamiento ocurre a frecuencias altas y cerca de los bordes de la banda de valencia y conducción, respectivamente. Los patrones de distribución de dopaje helicoidal y horizontal permiten un transporte de fonones adecuados cuantificados en una alta conductancia de fonones a 300K. Todos los hetero-nanotubos de nitruro de boro y carbono armchair (6, 6) poseen un comportamiento semiconductor a diferencia del nanotubo de carbono armchair (6, 6) con un bandgap modulable respecto a la concentración de dopaje de nitruro de boro. Por otra parte, los resultados del efecto de la temperatura del sustrato sobre el transporte térmico clásico en las hetero-nanocintas muestran que existe una influencia que incrementa la rectificación térmica (>30 %) a temperaturas bajas (>300K) para el sustrato de Si(100), esto debido al acople fuerte tipo Van der waals entre el sustrato y la hetero-nanocinta de nitruro de boro hexagonal/grafeno. Además, la asimetría estructural tipo-T genera una rectificación térmica en sistemas puros y hetero-nanocintas de grafeno/nitruro de boro hexagonal y nitruro de boro hexagonal/grafeno, este efecto está relacionado con los cambios en el grado de localización de los modos vibracionales de frecuencias altas . Sin embargo, la resistencia térmica interfacial y la rectificación térmica se reducen con la temperatura media en las XIV hetero-nanocintas de grafeno/X, independientemente de la interface armchair o zigzag, debido a que el flujo térmico en direcciones opuestas llegan a ser similares a altas temperaturas. El efecto de la temperatura bias, en la curva J − α, determina que el fujo térmico tiene una preferencia marcada en la dirección de X al grafeno, observando el fenomeno de la resistencia térmica diferencial negativa en los sistemas de grafeno/nitruro de boro hexagonal y grafeno/grafano. Por último, la trayectoria de mínima energía, la densidad de estados total y la densidad de estados proyectada del proceso de adsorción muestran que la molécula formaldehído, CH2O, se quimisorbe sobre el sustrato de hBN hidrogenado con una energía de adsorción de 1.42eV mediante vacancias de hidrógeno en el átomo de B, donde también la distribución de densidad de espín y la transferencia de carga presentan evidencias de la existencia de una reacción en cadena de moléculas CH2O sobre el sustrato de nitruro de boro hexagonal.
Consejo Nacional de Ciencia y Tecnología (Perú). Fondo Nacional de Desarrollo Científico y Tecnológico (Fondecyt)
Tesis
APA, Harvard, Vancouver, ISO, and other styles
7

Cindemir, Umut. "Thin films for indoor air monitoring : Measurements of Volatile Organic Compounds." Doctoral thesis, Uppsala universitet, Fasta tillståndets fysik, 2016. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-302558.

Full text
Abstract:
Volatile organic compounds (VOCs) in the indoor air have adverse effects on the dwellers residing in a building or a vehicle. One of these effects is called sick building syndrome (SBS). SBS refers to situations in which the users of a building develop acute health effects and discomfort depending on the time they spend inside some buildings without having any specific illness. Furthermore, monitoring volatile organic compounds could lead to early diagnosis of specific illnesses through breath analysis. Among those VOCs formaldehyde, acetaldehyde can be listed. In this thesis, VOC detecting thin film sensors have been investigated. Such sensors have been manufactured using semiconducting metal oxides, ligand activated gold nanoparticles and Graphene/TiO2 mixtures. Advanced gas deposition unit, have been used to produce NiO thin films and Au nanoparticles. DC magnetron sputtering has been used to produce InSnO and VO2 thin film sensors. Graphene/TiO2 sensors have been manufactured using doctor-blading. While presenting the results, first, material characterization details are presented for each sensor, then, gas sensing results are presented. Morphologies, crystalline structures and chemical properties have been analyzed using scanning electron microscopy, X-ray diffraction and X-ray photo electron spectroscopy. Furthermore, more detailed analyses have been performed on NiO samples using extended X-ray absorption fine structure method and N2 adsorption measurements. Gas sensing measurements were focused on monitoring formaldehyde and acetaldehyde. However, responses ethanol and methane were measured in some cases to monitor selectivity. Graphene/TiO2 samples were used to monitor NO2 and NH3. For NiO thin film sensors and Au nano particles, fluctuation enhanced gas sensing is also presented in addition to conductometric measurements.
APA, Harvard, Vancouver, ISO, and other styles
8

Paul, Mitchell Cameron. "Terahertz Molecular Spectroscopy as a Tool for Analytical Probing of Cellular Metabolism." Wright State University / OhioLINK, 2017. http://rave.ohiolink.edu/etdc/view?acc_num=wright1503928902745757.

Full text
APA, Harvard, Vancouver, ISO, and other styles
9

Stewart, Katherine Mariann Elizabeth. "Doped Polyaniline for Gas Sensors for the Detection of Formaldehyde." Thesis, 2011. http://hdl.handle.net/10012/5852.

Full text
Abstract:
Formaldehyde is one of the main gases that contribute to poor indoor air quality since it is so widely used in the manufacturing of goods. Over time, formaldehyde leaches out of various materials and reduces the quality of air. Formaldehyde, even at very low concentrations, can cause respiratory problems and a general feeling of unwellness. The World Health Organization (WHO) states that formaldehyde exposure should not exceed 0.08 ppm over a 30 minute period. Therefore, formaldehyde sensors are needed to ensure optimal indoor air quality. Polyaniline (PANI), as well as PANI doped with NiO or NiO and Al2O3, were tested to determine their suitability as sensing materials for formaldehyde. It was found that at higher concentrations of formaldehyde (above 1 ppm), PANI doped with 5% NiO and 15% Al2O3 was the most suitable sensing material with respect to both sensitivity and selectivity. At lower concentrations (below 1 ppm), however, PANI doped with 5% NiO and 15% Al2O3 did not detect formaldehyde. PANI doped with 15% NiO only was a much better option since it was able to detect the highest concentration of formaldehyde at very low concentrations (0.09 ppm) and still have moderate selectivity. A special test system was designed that could test single or multiple gases at various concentrations. Ethanol, acetaldehyde and benzene were chosen as interferents for formaldehyde and nitrogen was used to dilute the gases to achieve lower concentrations. A specialized gas chromatograph (GC) was used to determine the amount of gas or analyte that interacted with the sensing material being tested. Replicate polymer samples of varying dopant concentrations were tested with different gases at different concentrations and statistically analyzed. Both sensitivity and selectivity towards formaldehyde was taken into consideration. Among all tests conducted with single and multiple gases, it was concluded that PANI doped with 5% NiO and 15% Al2O3 was the best sensing material at high concentrations of formaldehyde (above 1 ppm), whereas PANI doped with 15% NiO was the best sensing material at low concentrations (below 1 ppm).
APA, Harvard, Vancouver, ISO, and other styles
10

Hsieh, Ping-Ru, and 謝秉儒. "Fabrication of Micro Formaldehyde Gas Sensor." Thesis, 2006. http://ndltd.ncl.edu.tw/handle/83767525429677899597.

Full text
Abstract:
碩士
大葉大學
機械工程研究所碩士班
94
ABSTRACT A novel micro formaldehyde gas sensor with a sputtered NiO thin film integrated with a micro hotplate was fabricated. A microfabricated formaldehyde gas sensor is developed which uses a silica substrate with Pt micro heaters as the micro hotplate and a thin-film NiO layer as a conductivity-sensitive material. The substrate is deposited with NiO thin film as sensing elements, Pt resistors as heaters, and as interdigitated electrodes for resistance measurement. As voltages were applied to Pt heaters, temperature of micro hotplates increased. Thus, at 300oC, when formaldehyde was present in the atmosphere, it was adsorbed and as a result the electrical conductivity of NiO films was increased. The measured resistance between the interdigitated electrodes was changed. The formaldehyde gas sensor was integrated with a Pt resistor as a micro heater for the enhancement of sensitivity. A high selectivity to acetone, methanol and ethanol was alson shown in the study.
APA, Harvard, Vancouver, ISO, and other styles
More sources

Book chapters on the topic "Formaldehyde sensors"

1

Debliquy, Marc, Arnaud Krumpmann, Driss Lahem, Xiaohui Tang, and Jean-Pierre Raskin. "Chemical Sensors for VOC Detection in Indoor Air: Focus on Formaldehyde." In Nanoscale Materials for Warfare Agent Detection: Nanoscience for Security, 47–70. Dordrecht: Springer Netherlands, 2019. http://dx.doi.org/10.1007/978-94-024-1620-6_4.

Full text
APA, Harvard, Vancouver, ISO, and other styles
2

Gupta, Jyoti, Prachi Singhal, and Sunita Rattan. "Formaldehyde Gas Sensor Based on MoS2/RGO 2D/2D Functional Nanocomposites." In Polymeric Biomaterials and Bioengineering, 159–65. Singapore: Springer Nature Singapore, 2022. http://dx.doi.org/10.1007/978-981-19-1084-5_15.

Full text
APA, Harvard, Vancouver, ISO, and other styles
3

Das, Shreyasi, Poulomi Chakrabarty, Tamal Dey, Sumita Santra, Soumen Das, and Samit K. Ray. "Room Temperature Detection of Formaldehyde with Economical and Ecofriendly Graphene Quantum Dot Ink Treated Paper-Based Sensor." In Lecture Notes in Bioengineering, 265–76. Singapore: Springer Singapore, 2021. http://dx.doi.org/10.1007/978-981-33-6915-3_28.

Full text
APA, Harvard, Vancouver, ISO, and other styles
4

Huang, H., C. C. Chen, and C. T. Tzeng. "A performance comparison study of the Sorptive Building Materials with MEMS-based formaldehyde gas sensor from the aspect of reduction efficiency of indoor formaldehyde concentration." In Testing and Measurement: Techniques and Applications, 93–96. CRC Press, 2015. http://dx.doi.org/10.1201/b18470-21.

Full text
APA, Harvard, Vancouver, ISO, and other styles

Conference papers on the topic "Formaldehyde sensors"

1

Acharyya, Snehanjan, Sayan Dey, Sudip Nag, and Prasanta Kumar Guha. "ZnO Cladded MnO2 Based Resistive Sensor Device for Formaldehyde Sensing." In 2018 IEEE Sensors. IEEE, 2018. http://dx.doi.org/10.1109/icsens.2018.8589683.

Full text
APA, Harvard, Vancouver, ISO, and other styles
2

Hassan, Muhammad, and Amine Bermak. "Threshold detection of carcinogenic odor of formaldehyde with wireless electronic nose." In 2014 IEEE Sensors. IEEE, 2014. http://dx.doi.org/10.1109/icsens.2014.6985266.

Full text
APA, Harvard, Vancouver, ISO, and other styles
3

Cindemir, Umut, Lars Osterlund, Gunnar A. Niklasson, Claes-Goran Granqvist, Maciej Trawka, and Janusz Smulko. "Nickel oxide thin film sensor for fluctuation-enhanced gas sensing of formaldehyde." In 2015 IEEE Sensors. IEEE, 2015. http://dx.doi.org/10.1109/icsens.2015.7370408.

Full text
APA, Harvard, Vancouver, ISO, and other styles
4

Lee, Chia-yen, Che-ming Chiang, Po-cheng Chou, Lung-ming Fu, and Che-hsin Lin. "A Novel Microfabricated Formaldehyde Gas Sensor with NiO Thin Film." In 2005 Sensors for Industry Conference. IEEE, 2005. http://dx.doi.org/10.1109/sicon.2005.257859.

Full text
APA, Harvard, Vancouver, ISO, and other styles
5

Dey, Sayan, Sumita Santra, Sabyasachi Sen, Debasree Burman, Samit K. Ray, and Prasanta K. Guha. "Photon assisted ultra-selective Formaldehyde sensing by defect induced NiO nanostructured sensing layer." In 2017 IEEE SENSORS. IEEE, 2017. http://dx.doi.org/10.1109/icsens.2017.8234446.

Full text
APA, Harvard, Vancouver, ISO, and other styles
6

Xu, Keng, and Dawen Zeng. "Hierarchical porous SnO2 topologically transferred from tin oxalate for fast response sensors to trace formaldehyde." In 2013 IEEE Sensors. IEEE, 2013. http://dx.doi.org/10.1109/icsens.2013.6688191.

Full text
APA, Harvard, Vancouver, ISO, and other styles
7

Manna, Bibhas, Snehanjan Acharyya, Indrajit Chakrabarti, and Prasanta Kumar Guha. "Exploring Formaldehyde Sensing Capability of Noble Metal Decorated Reduced Graphene Oxide through First Principle Approach." In 2019 IEEE SENSORS. IEEE, 2019. http://dx.doi.org/10.1109/sensors43011.2019.8956865.

Full text
APA, Harvard, Vancouver, ISO, and other styles
8

Guo, Miao, Ming-En Xu, Min Pan, and Yuquan Chen. "Effect of Thiol on Formaldehyde Sensors Based on CNTs." In 2009 3rd International Conference on Bioinformatics and Biomedical Engineering (iCBBE 2009). IEEE, 2009. http://dx.doi.org/10.1109/icbbe.2009.5162717.

Full text
APA, Harvard, Vancouver, ISO, and other styles
9

Xu, J., and L. Wang. "P2GS.1 - QCM formaldehyde sensing probes: design and sensing mechanism." In 17th International Meeting on Chemical Sensors - IMCS 2018. AMA Service GmbH, Von-Münchhausen-Str. 49, 31515 Wunstorf, Germany, 2018. http://dx.doi.org/10.5162/imcs2018/p2gs.1.

Full text
APA, Harvard, Vancouver, ISO, and other styles
10

Chia-Yen Lee, Yu-Hsiang Wang, Wen-Fu Ho, Rong-Hua Ma, and Po-Cheng Chou. "Formaldehyde Gas Sensor Utilizing Self-heating NiO Thin Film and Pt Electrodes." In 2006 5th IEEE Conference on Sensors. IEEE, 2006. http://dx.doi.org/10.1109/icsens.2007.355507.

Full text
APA, Harvard, Vancouver, ISO, and other styles
You might also be interested in the extended bibliographies on the topic 'Formaldehyde sensors' for particular source types:
Journal articles Dissertations / Theses
We offer discounts on all premium plans for authors whose works are included in thematic literature selections. Contact us to get a unique promo code!

To the bibliography