3,831 results on '"oxygen sensor"'
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2. A novel nonplanar multi-chamber flexible array dissolved oxygen sensor for aquaculture robotic fish
- Author
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Xu, Xianbao, Wang, Bingxiong, Du, Zhuangzhuang, Bai, Zhuangzhuang, Wang, Shuaixing, Wang, Cong, and Li, Daoliang
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- 2025
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3. Confocal dual-excitation PAS oxygen sensor utilizing 760 nm LED and reshaped differential resonator
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Han, Ze, Gong, Yongkang, Pang, Shuo, Sun, Jiachen, and Wang, Fupeng
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- 2025
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4. Influence of the orientation of constructed blood vessels during the 3D printing on the measurement of the pseudo-oxygen saturation of an artificial blood substitute using conventional oxygen sensors: a test series.
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Jung, Svenja, Hoffmann, Martin, Winkler, Dirk, Güresir, Erdem, Kropla, Fabian, Scholz, Sebastian, and Grunert, Ronny
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OXYGEN detectors ,BLOOD substitutes ,NICKEL sulfate ,OXYGEN saturation ,COPPER sulfate - Abstract
Background: The development of phantoms to reduce animal testing or to validate new instruments or operation techniques is of increasing importance. For this reason, a blood circulation phantom was developed to test a newly designed retractor system with an integrated oxygen sensor. This phantom was used to evaluate the impact of the 3D printed blood vessel on the measurement of the oxygen saturation. Methods: A solution of nickel sulfate and copper sulfate was prepared as a substitute for real blood. The absorption spectra of these solutions were recorded and compared with those of blood. Subsequently, the oxygen sensor used was calibrated to the blood substitute. Additionally, blood vessels with a simplified geometry were designed and manufactured using inverted vat polymerization and an elastic material (Formlabs Elastic 50 A). To determine the orientation during the printing process, various vessels were printed. Measurements to assess the effects of disturbance (rotation of the vessels during measurements) on the sensor readouts were prepared. Results: The impact of disturbances was verified through the rotation of the 3D printed vessels. It was demonstrated that a direct measurement on the disturbances led to outliers and higher values. An optimal orientation was determined to be a lateral placement (90° or 270°) of the sensor. Regarding the orientation of the vessels within the printing space, an orientation of 45° yielded the best results, as the individual layers had the least impact on the light emitted and received by the oxygen sensor. Conclusion: The achieved results demonstrate the influence of the orientation of the vessel during 3D printing as well as the influence of the position of the vessel during the measurement using a conventional oxygen sensor. [ABSTRACT FROM AUTHOR]
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- 2024
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5. Influence of the orientation of constructed blood vessels during the 3D printing on the measurement of the pseudo-oxygen saturation of an artificial blood substitute using conventional oxygen sensors: a test series
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Svenja Jung, Martin Hoffmann, Dirk Winkler, Erdem Güresir, Fabian Kropla, Sebastian Scholz, and Ronny Grunert
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3D print ,3D printed vessel ,Additive manufacturing ,Phantom ,Vascular phantom ,Oxygen sensor ,Medical physics. Medical radiology. Nuclear medicine ,R895-920 - Abstract
Abstract Background The development of phantoms to reduce animal testing or to validate new instruments or operation techniques is of increasing importance. For this reason, a blood circulation phantom was developed to test a newly designed retractor system with an integrated oxygen sensor. This phantom was used to evaluate the impact of the 3D printed blood vessel on the measurement of the oxygen saturation. Methods A solution of nickel sulfate and copper sulfate was prepared as a substitute for real blood. The absorption spectra of these solutions were recorded and compared with those of blood. Subsequently, the oxygen sensor used was calibrated to the blood substitute. Additionally, blood vessels with a simplified geometry were designed and manufactured using inverted vat polymerization and an elastic material (Formlabs Elastic 50 A). To determine the orientation during the printing process, various vessels were printed. Measurements to assess the effects of disturbance (rotation of the vessels during measurements) on the sensor readouts were prepared. Results The impact of disturbances was verified through the rotation of the 3D printed vessels. It was demonstrated that a direct measurement on the disturbances led to outliers and higher values. An optimal orientation was determined to be a lateral placement (90° or 270°) of the sensor. Regarding the orientation of the vessels within the printing space, an orientation of 45° yielded the best results, as the individual layers had the least impact on the light emitted and received by the oxygen sensor. Conclusion The achieved results demonstrate the influence of the orientation of the vessel during 3D printing as well as the influence of the position of the vessel during the measurement using a conventional oxygen sensor.
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- 2024
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6. Oxidation of Ni–30Cr Alloy at Low Temperature and Low Oxygen Partial Pressure: Experimental Methods to Improve Kinetics Constants Determination.
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Bosonnet, S., Huang, X., Bataillou, L., Martinelli, L., Fossati, Paul C. M., Latu-Romain, Laurence, Wouters, Yves, Desgranges, C., and Monceau, D.
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OXYGEN consumption , *OXYGEN detectors , *PARTIAL pressure , *OXIDATION kinetics , *MASS spectrometry - Abstract
Ni–30Cr model alloy was used to study chromia-scale formation behaviour. During its formation the mass variation signal is weak and it is important to take specific care to measure oxidation kinetics by thermogravimetric analysis. Symmetrical design allows the determination of very small mass changes in compensating buoyancy effects and limiting measurement drift. The mass variation measurement comprises noise coming from different sources that affects the electronic signal. It must be minimised to improve accuracy. This involves keeping the room-temperature constant, strictly balancing the beam and minimising buoyancy effects. By this way it was possible to acquire kinetics and to measured rate constants, kp, in a range from 3.10–5 to 3.10–10 mg2.cm−4.s−1 equivalent to 10–12 down to 10–17 cm2.s−1. Oxygen partial pressure ( P O 2 ) was monitor and revealed an abnormal consumption of oxygen at the beginning of the thermal exposure. Experiments with an inert material showed parasitic reactions identified by mass spectrometry as combustion of impurities. As oxygen consumption is not only due to oxidation of the sample, corrosion kinetics can't be deduced from it. Hence, to determine whether the oxygen supply from the gas is a limiting parameter, a model, which quantifies oxygen consumption by sample oxidation within the thermobalance, is proposed. [ABSTRACT FROM AUTHOR]
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- 2024
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7. Investigation of the Effect of the Trifluoropropynyl Ligand on Pt(N^C^N)X (X = Cl, C 2 CF 3) Complexes.
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Zimmerman, John H., Cahill, Benjamin J., Thomas, Wilson M., McCarthy, Jackson S., McMillen, Colin D., and Wagenknecht, Paul S.
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LIGANDS (Chemistry) ,OXYGEN detectors ,LIGHT emitting diodes ,SPACE groups ,PHOSPHORESCENCE ,PLATINUM - Abstract
The tuning of the luminescent properties of Pt
II complexes for possible use in organic light-emitting diodes (OLEDs) and sensing applications is commonly achieved by altering the electronic properties of the ligands. Our group recently demonstrated that the trifluoropropynyl ligand is strongly electron-withdrawing and possibly useful for blueshifting emission. Herein, we report the synthesis of two complexes of this trifluoropropynyl ligand, namely PtLC2 CF3 and PtLF C2 CF3 (L = 1,3-di(2-pyridyl)benzene; LF = 4,6-difluoro-1,3-di(2-pyridyl)benzene). The PtLC2 CF3 complex crystallized in the monoclinic space group P21 /n with Z = 4. The PtLF C2 CF3 complex crystalized in the triclinic space group P-1 with Z = 2. Changing the tridentate ligand from L to LF resulted in a change in the packing structure, with the latter showing a metallophilic interaction (Pt-Pt distance = 3.3341(3) Å). The solution photophysics of the trifluoropropynyl complexes is compared with that of the corresponding Cl complexes, PtLCl and PtLF Cl. Replacement of the chloro ligand with the trifluoropropynyl ligand blueshifted the monomer emission by less than 5 nm but blueshifted the excimer emission peaks by 15–20 nm. The complexes of the trifluoropropynyl ligand also favor the excimer emission more than the complexes of the chloro ligand. The excimer emission is quenched by dissolved oxygen significantly more than the corresponding monomer emission. The excimer emission and monomer emission are well separated, and the ratio of monomer to excimer emission is strongly dependent on oxygen concentration. [ABSTRACT FROM AUTHOR]- Published
- 2024
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8. Chromogenic Approach for Oxygen Sensing Using Tapered Coreless Optical Fibre Coated with Methylene Blue
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Rahul Kumar and Neil Wight
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fibre optic sensor (FOC) ,tapered coreless optical fibre ,oxygen sensor ,methylene blue ,Electronic computers. Computer science ,QA75.5-76.95 ,Applied mathematics. Quantitative methods ,T57-57.97 - Abstract
In this paper, a Methylene Blue (MB)-coated tapered coreless (TCL) optical fibre sensor is proposed and experimentally investigated for oxygen sensing in the near-infrared (NIR) wavelength range of 993.5 nm. The effect of TCL diameter and MB sol–gel coating thickness on the sensitivity of the sensor was also investigated. A maximum sensitivity of 0.19 dB/O2% in the oxygen concentration range of 0–37.5% was achieved for a TCL fibre sensor with a 2 µm taper waist diameter and a 0.86 µm MB sol–gel coating thickness, with a response time of 4 min. The sensor provides reproducible results even after 7 days and is shown to be highly selective to oxygen compared to argon and ethanol at the same concentration.
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- 2024
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9. Chromogenic Approach for Oxygen Sensing Using Tapered Coreless Optical Fibre Coated with Methylene Blue.
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Kumar, Rahul and Wight, Neil
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OXYGEN detectors ,METHYLENE blue ,OPTICAL fibers ,WAVELENGTHS ,SOL-gel processes - Abstract
In this paper, a Methylene Blue (MB)-coated tapered coreless (TCL) optical fibre sensor is proposed and experimentally investigated for oxygen sensing in the near-infrared (NIR) wavelength range of 993.5 nm. The effect of TCL diameter and MB sol–gel coating thickness on the sensitivity of the sensor was also investigated. A maximum sensitivity of 0.19 dB/O
2 % in the oxygen concentration range of 0–37.5% was achieved for a TCL fibre sensor with a 2 µm taper waist diameter and a 0.86 µm MB sol–gel coating thickness, with a response time of 4 min. The sensor provides reproducible results even after 7 days and is shown to be highly selective to oxygen compared to argon and ethanol at the same concentration. [ABSTRACT FROM AUTHOR]- Published
- 2024
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10. Optic Fiber Microsensor Reveals Specific Spatiotemporal Oxygen Uptake Profiles at the Mammalian Ocular Surface
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Sun, Qin, Ma, Li, Ferreira, Fernando, Brown, Chelsea, Reid, Brian, and Zhao, Min
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Analytical Chemistry ,Biochemistry and Cell Biology ,Chemical Sciences ,Biological Sciences ,Eye Disease and Disorders of Vision ,2.1 Biological and endogenous factors ,Rats ,Mice ,Animals ,Cornea ,Fiber Optic Technology ,Optical Fibers ,Oxygen ,Mammals ,cornea ,oxygen uptake ,spatiotemporal profile ,self-referencing probe ,oxygen sensor ,optical fiber sensor ,Biochemistry and cell biology ,Analytical chemistry - Abstract
Oxygen (O2) uptake by cells and tissues is a critical indicator of metabolic demand, changes in microenvironment, and pathophysiology. O2 uptake from the atmosphere accounts for virtually all the O2 consumption in the avascular cornea; however, a detailed spatiotemporal profile of corneal O2 uptake (COU) remains undetermined. Here, we used a non-invasive self-referencing optical fiber O2 sensor-the scanning micro-optrode technique (SMOT)-to report the O2 partial pressure and flux variations at the ocular surface of rodents and non-human primates. In vivo spatial mapping in mice revealed a distinct COU, characterized by a centripetal gradient with a significantly higher O2 influx at the limbus and conjunctiva regions than at the center of the cornea. This regional COU profile was reproduced ex vivo in freshly enucleated eyes. The centripetal gradient was conserved across the following species analyzed: mice, rats, and rhesus monkeys. In vivo temporal mapping in mice showed a significant increase in the O2 flux in the limbus in the evening compared to other times. Altogether, the data unveiled a conserved centripetal COU profile, which may be associated with the limbal epithelial stem cells residing at the intersection of the limbus and conjunctiva. These physiological observations will serve as a useful baseline for comparative studies with contact lens wear, ocular disease, diabetes, etc. Moreover, the sensor may be applied to understand the responses of the cornea and other tissues to various insults, drugs, or changes in the environment.
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- 2023
11. Aligned nanofibers incorporated composite solid electrolyte for high-sensitivity oxygen sensing at medium temperatures.
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Zhang, Mengfei, Yao, Lei, Xing, Yan, Cheng, Jing, Yang, Tianrang, Liu, Jianguo, and Pan, Wei
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SOLID electrolytes ,SUPERIONIC conductors ,CONDUCTIVITY of electrolytes ,NANOFIBERS ,OXYGEN detectors ,INTERNAL combustion engines ,IONIC conductivity - Abstract
• A miniaturized oxygen sensor has been developed with high sensitivity at 300 °C. • The micro-sensor assembled with well-aligned nanofibers embedded in the matrix. • The conduction advantage of nanofibers is first applied in an oxygen sensor. • The conductivity of composite electrolyte is four times higher than that of YSZ. Potentiometric oxygen sensors have been widely used in internal combustion engines, industrial boilers, and metallurgical heat treatment furnaces. However, traditional oxygen sensors based on yttria-stabilized zirconia (YSZ) electrolyte can only be operated at elevated temperatures (> 750 °C) due to their relatively low ionic conductivity. In this study, we present a highly efficient micro-oxygen sensor that can be operated at a temperature as low as 300 °C. This micro-oxygen sensor incorporates a composite solid electrolyte, i.e., well-aligned gadolinium-doped cerium oxide (CGO) nanofibers embedded within a YSZ matrix (YSZ/CGO f). The arrays of CGO nanofibers in the YSZ matrix are parallel to the conduction direction, providing rapid conducting channels for oxygen ions. Benefitting from this design, the composite electrolyte leads to a conductivity of four times higher than that of traditional YSZ solid electrolytes at low temperatures. This enhancement in conductivity is attributed to the presence of a defective interfacial region between CGO f and YSZ, which promotes the mobility of oxygen ions. The strategy of constructing fast ionic conduction in the composite electrolyte by using well-aligned nanofibers may be considered for the design and optimization of other micro/nano-devices including sensors, batteries, and fuel cells. [Display omitted] [ABSTRACT FROM AUTHOR]
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- 2024
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12. Selective Hypoxia-Sensitive Oxomer Formation by FIH Prevents Binding of the NF-κB Inhibitor IκBβ to NF-κB Subunits.
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Volkova, Yulia L., Jucht, Agnieszka E., Oechsler, Nina, Krishnankutty, Roopesh, von Kriegsheim, Alex, Wenger, Roland H., and Scholz, Carsten C.
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OXYGEN detectors , *AMINO acid sequence - Abstract
Pharmacologic inhibitors of cellular hydroxylase oxygen sensors are protective in multiple preclinical in vivo models of inflammation. However, the molecular mechanisms underlying this regulation are only partly understood, preventing clinical translation. We previously proposed a new mechanism for cellular oxygen sensing: oxygen-dependent, (likely) covalent protein oligomer (oxomer) formation. Here, we report that the oxygen sensor factor inhibiting HIF (FIH) forms an oxomer with the NF-κB inhibitor β (IκBβ). The formation of this protein complex required FIH enzymatic activity and was prevented by pharmacologic inhibitors. Oxomer formation was highly hypoxia-sensitive and very stable. No other member of the IκB protein family formed an oxomer with FIH, demonstrating that FIH-IκBβ oxomer formation was highly selective. In contrast to the known FIH-dependent oxomer formation with the deubiquitinase OTUB1, FIH-IκBβ oxomer formation did not occur via an IκBβ asparagine residue, but depended on the amino acid sequence VAERR contained within a loop between IκBβ ankyrin repeat domains 2 and 3. Oxomer formation prevented IκBβ from binding to its primary interaction partners p65 and c-Rel, subunits of NF-κB, the master regulator of the cellular transcriptional response to pro-inflammatory stimuli. We therefore propose that FIH-mediated oxomer formation with IκBβ contributes to the hypoxia-dependent regulation of inflammation. [ABSTRACT FROM AUTHOR]
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- 2024
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13. Reliable and inexpensive dissolved oxygen sensing materials.
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Gießel, Alexander, Ziebart, Nandor, Lenk, Felix, and Walther, Thomas
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PLATINUM electrodes , *SCREEN process printing , *WIRE , *OXYGEN , *OXYGEN detectors , *ELECTRODES , *WATER salinization - Abstract
Bare, non-pretreated platinum wires and screen-printed platinum electrodes were used as both working and counter electrodes in the measurement of dissolved oxygen using a chronoamperometric method. The oxygen reduction current response in the diffusion state was used for a linear determination of air saturation. We evaluated the two different materials in general for their sensing performance such as conditioning time, accuracy, resolution and stability over 13 h of continuous mid-term measurement. A good performance was found for the wire electrodes in terms of accuracy with a current slope of 1.0–1.6 µA (% as)-1 and a resolution of 10–15 nA (Lowest Level of Detection = 0.1% as), but with an unstable current response result over the course of the measurement. The screen-printed electrodes have a resolution of 10–18 nA (Lowest Level of Detection = 0.6–0.8% as) and an accuracy of 620–660 nA (% as)-1 but they showed promising reproducibility and stability. Both materials require several hours of conditioning in the chronoamperometric method before a stable current response is achieved. For biotechnological applications, the platinum screen printed electrodes were evaluated in typical parameter settings (pH 4.0 and 7.4, salinity 0.1 to 10x phosphate buffered saline and temperature 12 to 42 °C) and showed correlations between the response time and stability and the temperature. No correlations were found between salinity, pH and the current response. In this paper, we present inexpensive electrode materials and a simple to implement chronoamperometric method for reliable direct measurement of dissolved oxygen in aqueous media. [ABSTRACT FROM AUTHOR]
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- 2024
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14. Vacuum Packaging Sensor Based on Time-Resolved Phosphorescence Spectroscopy
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Esmaeil Heydari, Fatemeh Yari, and Hossein Zare-Behtash
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Caviar ,photoluminescence lifetime ,oxygen sensor ,platinum porphyrin complex ,vacuum packaging ,Applied optics. Photonics ,TA1501-1820 - Abstract
Abstract Intelligent food packaging with the multisensory analysis is promising as the next generation technology of food packaging. The oxygen content in food packaging is one of the crucial parameters affecting the food quality and shelf life. Caviar is among the most nutritious and costly food sources. Here, a photonic oxygen-sensing system, based on the time-resolved phosphorescence spectroscopy of a platinum complex, is developed for non-contact, non-intrusive, and real-time vacuum packaging quality control, and implemented for caviar packaging. The sensor is embedded in protective polyethylene layers and excited with a short-pulsed light emitting diode (LED) source. Integration of a blue pulsed light source, a fast and amplified silicon photodiode controlled by the Spartan-6 field programmable gate array (FPGA), and a long lifetime platinum complex results in a photonics-based oxygen sensor with a fast response and high sensitivity to the vacuum packaging damage, which is suitable for caviar. It is revealed that applying the polyethylene layers protects the caviar from the platinum complex, leaching while not interfering with the sensor functionality. Characterizing the photonic system based on its sensitivity, repeatability, stability, and long-term operation demonstrates its capability for this application.
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- 2023
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15. Vacuum Packaging Sensor Based on Time-Resolved Phosphorescence Spectroscopy.
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Heydari, Esmaeil, Yari, Fatemeh, and Zare-Behtash, Hossein
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PHOSPHORESCENCE spectroscopy ,VACUUM packaging ,TIME-resolved spectroscopy ,FIELD programmable gate arrays ,LIGHT emitting diodes ,OXYGEN detectors - Abstract
Intelligent food packaging with the multisensory analysis is promising as the next generation technology of food packaging. The oxygen content in food packaging is one of the crucial parameters affecting the food quality and shelf life. Caviar is among the most nutritious and costly food sources. Here, a photonic oxygen-sensing system, based on the time-resolved phosphorescence spectroscopy of a platinum complex, is developed for non-contact, non-intrusive, and real-time vacuum packaging quality control, and implemented for caviar packaging. The sensor is embedded in protective polyethylene layers and excited with a short-pulsed light emitting diode (LED) source. Integration of a blue pulsed light source, a fast and amplified silicon photodiode controlled by the Spartan-6 field programmable gate array (FPGA), and a long lifetime platinum complex results in a photonics-based oxygen sensor with a fast response and high sensitivity to the vacuum packaging damage, which is suitable for caviar. It is revealed that applying the polyethylene layers protects the caviar from the platinum complex, leaching while not interfering with the sensor functionality. Characterizing the photonic system based on its sensitivity, repeatability, stability, and long-term operation demonstrates its capability for this application. [ABSTRACT FROM AUTHOR]
- Published
- 2024
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16. Oligohexamethylene Guanidine Derivative as a Means to Prevent Biological Fouling of a Polymer-Based Composite Optical Oxygen Sensor.
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Lisowski, Maxim D., Korobova, Elizaveta V., Naumova, Alina O., Sedishev, Igor P., Markova, Alina A., Nguyen, Minh Tuan, Kuzmin, Vladimir A., Nichugovskiy, Artemiy I., Arlyapov, Vyacheslav A., Yashtulov, Nikolay A., and Melnikov, Pavel V.
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OXYGEN detectors , *OPTICAL sensors , *CONTACT angle , *FOULING , *MYCOBACTERIUM smegmatis , *GUANIDINE derivatives , *GUANIDINES - Abstract
The use of biocidal agents is a common practice for protection against biofouling in biomass-rich environments. In this paper, oligohexamethyleneguanidine (OHMG) polymer, known for its biocidal properties, was further modified with para-aminosalicylic acid (PAS) to enhance its properties against microorganisms coated with a lipid membrane. The structure of the product was confirmed by 1H NMR, 13C NMR, and FTIR spectroscopy. The values of the minimum inhibitory concentration (MIC) against Mycobacterium smegmatis ATCC 607 and Pseudomonas chlororaphis 449 were found to be 1.40 and 1.05 μg/mL, respectively. The synthesized substance was used as an additive to the polymer matrix of the composite optical oxygen sensor material. A series of samples with different contents of OHMG-PAS was prepared using a co-dissolution method implying the fabrication of a coating from a solution containing both polymers. It turned out that the mutual influence of the components significantly affects the distribution of the indicator in the matrix, surface morphology, and contact angle. The optimal polymer content turned out to be wt.3%, at which point the water contact angle reaches almost 122°, and the fouling rate decreases by almost five times, which is confirmed by both the respiratory MTT assay and confocal microscopy with staining. This opens up prospects for creating stable and biofouling-resistant sensor elements for use in air tanks or seawater. [ABSTRACT FROM AUTHOR]
- Published
- 2023
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17. Low Temperature Performance of LBE Oxygen Sensors with Different Reference Electrodes
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Qi, Mu-Ran, Tang, Yun-Peng, Zhu, Hui-Ping, Li, Xiao-Bo, Liang, Rui-Xian, Zhao, Yun-Gan, Wang, Yi-Feng, Niu, Feng-Lei, and Liu, Chengmin, editor
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- 2023
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18. Electrochemical Monitoring of Oxygen Potential on Fe-Cr Alloy Surface During High Temperature Oxidation in Dry and Humid Conditions
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Ani, M. H., Purwanto, H., Musa, M., Illias, S., Kaderi, A., Salim, N., Rahim, M. H. A., Sutjipto, A. G. E., Cavas-Martínez, Francisco, Editorial Board Member, Chaari, Fakher, Series Editor, di Mare, Francesca, Editorial Board Member, Gherardini, Francesco, Series Editor, Haddar, Mohamed, Editorial Board Member, Ivanov, Vitalii, Series Editor, Kwon, Young W., Editorial Board Member, Trojanowska, Justyna, Editorial Board Member, Jalar, Azman, editor, Embong, Zaidi, editor, Othman, Norinsan Kamil, editor, Yaakob, Najmiddin, editor, and Bakar, Maria Abu, editor
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- 2023
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19. Regulating anaerobic metabolism and promoting myocardial ischemia-hypoxia injury by diesel particulate matter and its key component benzo[a]pyrene via targeting oxygen sensors
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Hao YIN, Ze ZHANG, Liu WU, Yingzhu WANG, Yuxin ZHENG, and Xiaoting JIN
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diesel particulate matter ,benzo[a]pyrene ,ischemia-hypoxia injury ,hypoxia-inducible factor-1 alpha ,oxygen sensor ,anaerobic metabolism ,Medicine (General) ,R5-920 ,Toxicology. Poisons ,RA1190-1270 - Abstract
BackgroundThe exposure to diesel particulate matter (DPM) and its polycyclic aromatic hydrocarbons (PAH) is closely related to the morbidity and mortality of ischemic heart disease (IHD). However, it is unclear what key components and targets of DPM exposure involve in myocardial ischemia-hypoxia injury and associated mechanisms.ObjectiveTo identify key PAH components of DPM that act on myocardial hypoxic injury, andclarify the role of oxygen sensors-regulated anaerobic metabolism in DPM and key components-induced hypoxic injury and the targets of the key PAH components.MethodsHuman cardiomyocyte cell line AC16 cells were exposed to 0, 1, 5, and 10 μg·mL−1 DPM in a high glucose DMEM medium with 10% fetal bovine serum (FBS) (HGM) or low FBS (0.5%) in high glucose DMEM medium (LFM), for 12 h under 2% O2, and expression of hypoxia-inducible factor-1α (HIF-1α), Bax, and Cleaved-caspase3 was determined by Western blotting. Under normal condition, the cell viability was detected after PAH exposure for 12 h. Under the condition of ischemia-hypoxia model, cells were exposed to 0, 0.005, 0.5, and 5 µg·mL−1 PAH for 12 h, and the protein expression of HIF-1α, Bax, and Cleaved-caspase3 was determined. After exposure to DPM or PAH for 12 h, the contents of pyruvate and lactate in cells were detected. Pretreatment with glycolysis inhibitor GSK2837808A was used to explore the role of glycolysis in DPM and benzo[a]pyrene (BaP)-induced hypoxia injury. A molecular docking technique was used to analyze the binding affinity between PAH and oxygen sensors (prolyl hydroxylase domain-containing protein 2, PHD2, and factor-inhibiting hypoxia-inducible factor 1, FIH1), and the protein levels of PHD2, FIH1, and hydroxyl-HIF-1-alpha (OH-HIF-1α) after the DPM or BaP treatment were further determined.ResultsUnder hypoxia, DPM exposure in the LFM induced the expression of HIF-1α, Bax, and Cleaved-caspase3 (P0.05), other PAH decreased cell viability when the concentration was above 1 μg·mL−1 (P
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- 2023
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20. Investigation of the Effect of the Trifluoropropynyl Ligand on Pt(N^C^N)X (X = Cl, C2CF3) Complexes
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John H. Zimmerman, Benjamin J. Cahill, Wilson M. Thomas, Jackson S. McCarthy, Colin D. McMillen, and Paul S. Wagenknecht
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phosphorescence ,OLED ,platinum(II) ,excimer ,oxygen sensor ,Crystallography ,QD901-999 - Abstract
The tuning of the luminescent properties of PtII complexes for possible use in organic light-emitting diodes (OLEDs) and sensing applications is commonly achieved by altering the electronic properties of the ligands. Our group recently demonstrated that the trifluoropropynyl ligand is strongly electron-withdrawing and possibly useful for blueshifting emission. Herein, we report the synthesis of two complexes of this trifluoropropynyl ligand, namely PtLC2CF3 and PtLFC2CF3 (L = 1,3-di(2-pyridyl)benzene; LF = 4,6-difluoro-1,3-di(2-pyridyl)benzene). The PtLC2CF3 complex crystallized in the monoclinic space group P21/n with Z = 4. The PtLFC2CF3 complex crystalized in the triclinic space group P-1 with Z = 2. Changing the tridentate ligand from L to LF resulted in a change in the packing structure, with the latter showing a metallophilic interaction (Pt-Pt distance = 3.3341(3) Å). The solution photophysics of the trifluoropropynyl complexes is compared with that of the corresponding Cl complexes, PtLCl and PtLFCl. Replacement of the chloro ligand with the trifluoropropynyl ligand blueshifted the monomer emission by less than 5 nm but blueshifted the excimer emission peaks by 15–20 nm. The complexes of the trifluoropropynyl ligand also favor the excimer emission more than the complexes of the chloro ligand. The excimer emission is quenched by dissolved oxygen significantly more than the corresponding monomer emission. The excimer emission and monomer emission are well separated, and the ratio of monomer to excimer emission is strongly dependent on oxygen concentration.
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- 2024
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21. Genetically Encoded Biosensors for the Fluorescence Detection of O 2 and Reactive O 2 Species.
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Marchetti, Marialaura, Ronda, Luca, Cozzi, Monica, Bettati, Stefano, and Bruno, Stefano
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GREEN fluorescent protein , *BIOSENSORS , *FLUORESCENCE resonance energy transfer , *HEMOPROTEINS , *FLUORESCENCE , *HYPOXIA-inducible factor 1 , *FLUORESCENT proteins - Abstract
The intracellular concentrations of oxygen and reactive oxygen species (ROS) in living cells represent critical information for investigating physiological and pathological conditions. Real-time measurement often relies on genetically encoded proteins that are responsive to fluctuations in either oxygen or ROS concentrations. The direct binding or chemical reactions that occur in their presence either directly alter the fluorescence properties of the binding protein or alter the fluorescence properties of fusion partners, mostly consisting of variants of the green fluorescent protein. Oxygen sensing takes advantage of several mechanisms, including (i) the oxygen-dependent hydroxylation of a domain of the hypoxia-inducible factor-1, which, in turn, promotes its cellular degradation along with fluorescent fusion partners; (ii) the naturally oxygen-dependent maturation of the fluorophore of green fluorescent protein variants; and (iii) direct oxygen binding by proteins, including heme proteins, expressed in fusion with fluorescent partners, resulting in changes in fluorescence due to conformational alterations or fluorescence resonance energy transfer. ROS encompass a group of highly reactive chemicals that can interconvert through various chemical reactions within biological systems, posing challenges for their selective detection through genetically encoded sensors. However, their general reactivity, and particularly that of the relatively stable oxygen peroxide, can be exploited for ROS sensing through different mechanisms, including (i) the ROS-induced formation of disulfide bonds in engineered fluorescent proteins or fusion partners of fluorescent proteins, ultimately leading to fluorescence changes; and (ii) conformational changes of naturally occurring ROS-sensing domains, affecting the fluorescence properties of fusion partners. In this review, we will offer an overview of these genetically encoded biosensors. [ABSTRACT FROM AUTHOR]
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- 2023
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22. 基于多掺杂的CeO2和La0.8Sr0.2Fe0.7Ni0.3O3-δ极限电流型氧传感器 的制备及性能研究.
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姜晓峰, 周芬, 郜建全, and 宋希文
- Abstract
Copyright of Journal of the Chinese Society of Rare Earths is the property of Editorial Department of Journal of the Chinese Society of Rare Earths and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)
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- 2023
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23. Lead-free double perovskite halide fluorescent oxygen sensor with high stability.
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Liu, Yuping, Gao, Long, Cheng, Tuo, Zhang, Xin, Li, Yexi, Zhang, Xiaoyu, Zheng, Weitao, Wang, Yinghui, and Zhang, Jiaqi
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OXYGEN detectors , *PEROVSKITE , *DETECTION limit , *LEAD halides , *HALIDES , *THERMAL stability , *THIN films - Abstract
Oxygen sensors, using organic-inorganic and all-inorganic lead halide perovskites, have demonstrated huge advantages in operating temperature, responding time, and reversing oxygen content detection. Nevertheless, the toxicity and instability issues hinder their wide application. In this work, for the first time, we report a sensitive fluorescence oxygen detector based on lead-free double perovskite Cs 2 AgBiBr 6 thin film. The sensor has a remarkable performance in terms of fast response time of ≈56 s, recovery time of ≈91 s, and a relatively low limit of detection (LOD) of 150 ppm. More importantly, the unencapsulated sensor still exhibits an obvious response at low oxygen concentrations after two-week storage in ambient, and the device also exhibits good humidity, light, and thermal stability. Consequently, the lead-free double perovskite (Cs 2 AgBiBr 6) will be promising environmentally friendly material in developing reversible, sensitive, high-efficiency, and stable perovskite oxygen sensors. [ABSTRACT FROM AUTHOR]
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- 2023
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24. High-Performance MEMS Oxygen Sensors Based on Au/TiO 2 Films.
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Jiao, Mingzhi, Zhao, Xiaohu, He, Xinjian, Wang, Gang, Zhang, Wei, Rong, Qian, and Nguyen, DucHoa
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OXYGEN detectors ,TITANIUM dioxide ,THIN films ,MICROELECTROMECHANICAL systems ,NANOFILMS ,SURFACE properties - Abstract
High-performance microelectromechanical system (MEMS) oxygen sensors were realized by successful preparation of Au nanofilms over TiO
2 thin films through successive sputtering on commercial MEMS microhotplates. Oxygen sensing performance of 3 and 6 nm thick Au over TiO2 thin films were compared with that of pure TiO2 thin films. It was shown that 6 nm thick Au over TiO2 thin films have the best sensitivity toward oxygen. The prepared TiO2 thin films were characterized using SEM, EDS, XPS, and a gas testing instrument. The results show that Au decoration has little influence on the surface morphologies of TiO2 thin films. However, Au decoration has a strong influence on the surface properties of the composite films. The favorable performance of 6 nm Au-doped TiO2 thin films is attributed to factors such as catalytical performance, height of Schottky contact, and number of oxygen vacancies. This work makes contributions to low power consumption and high-performance oxygen sensors for Internet of Things applications. [ABSTRACT FROM AUTHOR]- Published
- 2023
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25. Hypoxia Primes Human ISCs for Interleukin-Dependent Rescue of Stem Cell ActivitySummary
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Kristina R. Rivera, R. Jarrett Bliton, Joseph Burclaff, Michael J. Czerwinski, Jintong Liu, Jessica M. Trueblood, Caroline M. Hinesley, Keith A. Breau, Halston E. Deal, Shlok Joshi, Vladimir A. Pozdin, Ming Yao, Amanda L. Ziegler, Anthony T. Blikslager, Michael A. Daniele, and Scott T. Magness
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Inflammatory Hypoxia ,Microphysiological System ,Intestinal Stem Cells ,Stem Cell Priming ,Oxygen Sensor ,Cytokines ,Diseases of the digestive system. Gastroenterology ,RC799-869 - Abstract
Background and Aims: Hypoxia in the intestinal epithelium can be caused by acute ischemic events or chronic inflammation in which immune cell infiltration produces inflammatory hypoxia starving the mucosa of oxygen. The epithelium has the capacity to regenerate after some ischemic and inflammatory conditions suggesting that intestinal stem cells (ISCs) are highly tolerant to acute and chronic hypoxia; however, the impact of hypoxia on human ISC (hISC) function has not been reported. Here we present a new microphysiological system (MPS) to investigate how hypoxia affects hISCs from healthy donors and test the hypothesis that prolonged hypoxia modulates how hISCs respond to inflammation-associated interleukins (ILs). Methods: hISCs were exposed to
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- 2023
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26. Solution-processed ZnO nanoparticles for optically addressed spatial light modulators and other applications
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Chang, Xin and Chu, Daping
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537 ,ZnO nanoparticles ,Optically addressed spatial light modulator (OASLM) ,Oxygen sensor ,Organic electrochemical transistor ,Self-assembly - Abstract
Solution-processable materials are becoming increasingly attractive due to their use in low cost, high throughput and relatively easy fabrications. In addition, the possibility of high-resolution patterning makes solution-based materials particularly suitable for integrated applications. The material that was investigated in this work is zinc oxide nanoparticles (ZnO NPs) dispersion, motivated by the highest resolution on record of optically addressed spatial light modulators (OASLMs) using solution-based ZnO NP as photoactive material. ZnO is a popular type of semiconductor compound from II-VI group and ZnO NPs are the nanocrystalline form of ZnO, which exhibit many unique and superior properties such as direct and wide bandgap, large surface-to-volume ratio, antibacterial and eco-friendly nature. Therefore, the investigation of ZnO NPs in terms of their physical properties, post processing effect, patterning techniques, and applications are of great significance. In this work, thin films made from ZnO NP dispersion in ethanol was characterized in detail including their structural, electrical, dielectric and optical properties. The post-processing effect such as thermal annealing and oxygen plasma treatment was also investigated. Then ZnO NP-based OASLM was researched by simulation and device characterization regarding electrical and optical properties. More importantly, the optimization of ZnO NP-based OASLMs was conducted in terms of diffraction efficiency and response speed, which are two key factors limiting the development of ZnO NP-based OASLMs. The diffraction efficiency was improved by pinpointing the optimum parameters of the driving signal such as waveform, amplitude and frequency. And the response time was reduced by several methods such as thermal annealing, introducing an interfacial layer and replacing the photoconductive ZnO NP layer with ZnO NP-based photodiode structure. The sensing of oxygen partial pressure in air by ZnO NP thin film was also observed and studied. Moreover, device miniaturization was achieved by the mould-guided drying technique, indicating a promising future for integrated applications. This patterning technique was also used for another type of solution-based material: PEDOT:PSS. And PEDOT:PSS-based organic electrochemical transistors (OECTs) with nanoscale channel length and channel width were realized by including a lift-off process, which demonstrated a great high-frequency response.
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- 2020
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27. Interfacial compatibility and thermal cycle stability for glass-sealed oxygen sensors.
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Tao, Mengxuan, Feng, Jiangtao, Li, Ruizhu, Guan, Chengzhi, Wang, Jianqiang, Chi, Bo, and Pu, Jian
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OXYGEN detectors , *THERMOCYCLING , *THERMAL stability , *ALUMINUM oxide , *ZIRCONIUM oxide , *METALLIC glasses , *OXYGEN - Abstract
The oxygen sensors are extensively utilized in vehicles' exhaust systems to monitor gases composition and control air-to-fuel ratio, thus reducing harmful emission and improving fuel economy. In equilibrium potentiometric sensors, the sealing performance is essential to ensure data accuracy. In this work, the 64SiO 2 –18TiO 2 –10Na 2 O–7K 2 O–1Al 2 O 3 (wt%) glass was utilized as seals instead of traditional talcum in zirconium dioxide oxygen sensor. The interfacial compatibility with adjacent components (Fe–16Cr, Al 2 O 3 and 8YSZ) and thermal cycle stability of seals were seriously evaluated in various ways. The equilibrium contact angles were lower 60° at high temperature, exhibiting better wettability and tight bonding at the interface. Besides, the leakage rates between glass and Fe–16Cr alloy were less than 0.01 sccm/cm at 650–800 °C and input gas pressures of 6.9–34.5 kPa. The oxygen sensor coupled with glass exhibited better thermal stability that leakage rate maintained around 0.004 sccm/cm under an input gas pressure of 200 kPa during 100 thermal cycles. Additionally, the oxygen sensor with sealed glass can generate continuous response and recovery, which is better than sealed talcum. Owing to these good performance, the glass is a suitable alternative for oxygen sensor sealing. [ABSTRACT FROM AUTHOR]
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- 2023
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28. Low Temperature Chemoresistive Oxygen Sensors Based on Titanium-Containing Ti 2 CT x and Ti 3 C 2 T x MXenes.
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Simonenko, Elizaveta P., Nagornov, Ilya A., Mokrushin, Artem S., Kashevsky, Sergey V., Gorban, Yulia M., Simonenko, Tatiana L., Simonenko, Nikolay P., and Kuznetsov, Nikolay T.
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OXYGEN detectors , *LOW temperatures , *MATERIALS at low temperatures , *PARTIAL oxidation , *AIR flow - Abstract
The chemoresistive properties of multilayer titanium-containing Ti2CTx and Ti3C2Tx MXenes, synthesized by etching the corresponding MAX phases with NaF solution in hydrochloric acid, and the composites based on them, obtained by partial oxidation directly in a sensor cell in an air flow at 150 °C, were studied. Significant differences were observed for the initial MXenes, both in microstructure and in the composition of surface functional groups, as well as in gas sensitivity. For single Ti2CTx and Ti3C2Tx MXenes, significant responses to oxygen and ammonia were observed. For their partial oxidation at a moderate temperature of 150 °C, a high humidity sensitivity (T, RH = 55%) is observed for Ti2CTx and a high and selective response to oxygen for Ti3C2Tx at 125 °C (RH = 0%). Overall, these titanium-containing MXenes and composites based on them are considered promising as receptor materials for low temperature oxygen sensors. [ABSTRACT FROM AUTHOR]
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- 2023
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29. Oxidation Behavior of Pure Iron under Hydrogen Combustion Environment.
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Fukumoto, Michihisa, Hara, Seiya, and Takahashi, Hiroki
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OXYGEN detectors ,HYDROGEN detectors ,COMBUSTION ,HYDROGEN ,BORDERLANDS ,HYDROGEN as fuel - Abstract
The environmental resistance of pure iron was evaluated by an oxygen and hydrogen sensor installed after an oxidation furnace. The amount of introduced oxygen was precisely controlled by the oxygen pump sensor at the front stage of the oxidation furnace, and the reaction with hydrogen was analyzed. Thus, when oxygen was supplied, a reaction between hydrogen and oxygen occurred; however, when the supplied oxygen was not sufficient, a hydrogen-vapor environment was created, and oxidation was not accelerated. Conversely, when the amount of supplied oxygen was excessive, the environment became an oxygen–steam environment, and oxidation was accelerated. Therefore, this explained how the oxidation caused by oxygen was dominant under the oxygen–water vapor environment, and the oxidation weight gain increased. In addition, the border of the region dominated by oxygen oxidation and steam oxygen was clarified by precisely controlling the amount of oxygen supplied by the oxygen pump sensor. [ABSTRACT FROM AUTHOR]
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- 2023
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30. Application of tris -(4,7-Diphenyl-1,10 phenanthroline)ruthenium(II) Dichloride to Detection of Microorganisms in Pharmaceutical Products †.
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Hałasa, Rafał, Turecka, Katarzyna, Smoktunowicz, Magdalena, Mizerska, Urszula, and Orlewska, Czesława
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DETECTION of microorganisms , *RUTHENIUM , *PHENANTHROLINE , *PLANT extracts , *MICROBIAL cells - Abstract
tris-[(4,7-diphenyl-1,10-phenanthroline)ruthenium(II)] dichloride (Ru(DPP)3Cl2), a fluorescent sensor which is sensitive to the amount of oxygen in the sample, was applied using the fluorescent optical respirometry (FOR) technique. The oxygen in the samples quenches the fluorescence. The fluorescence intensity depends on the metabolic rate of the viable microorganisms. The effect of DMSO and plant extracts on bacteria was determined by FOR. It was shown that the MIC values obtained by FOR were consistent with the results of the MIC determinations using the method of serial dilutions; at the same time, the effects of concentrations lower than the growth-inhibitory concentrations on microbial cells were demonstrated. The FOR method enables the detection of multiplying bacteria in sterile and non-sterile pharmaceutical preparations in real time, which significantly shortens the time required to obtain results and allows the introduction of repair processes in the production. This method also allows for quick, unambiguous detection and the counting of the viable cells of aerobic microorganisms in non-sterile pharmaceuticals. [ABSTRACT FROM AUTHOR]
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- 2023
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31. Development of a Stable Oxygen Sensor Using a 761 nm DFB Laser and Multi-Pass Absorption Spectroscopy for Field Measurements.
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Chang, Jvqiang, He, Qixin, and Li, Mengxin
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OXYGEN detectors , *DISTRIBUTED feedback lasers , *MODULATION spectroscopy , *ATMOSPHERIC oxygen , *OPTICAL sensors , *ABSORPTION , *OXYGEN consumption - Abstract
An optical sensor system based on wavelength modulation spectroscopy (WMS) was developed for atmospheric oxygen (O2) detection. A distributed feedback (DFB) laser with butterfly packaging was used to target the O2 absorption line at 760.89 nm. A compact multi-pass gas cell was employed to increase the effective absorption length to 3.3 m. To ensure the stability and anti-interference capability of the sensor in field measurements, the optical module was fabricated with isolation of ambient light and vibration design. A 1f normalized 2f WMS (WMS-2f/1f) technique was adopted to reduce the effect of laser power drift. In addition, a LabVIEW-based dual-channel lock-in amplifier was developed for harmonic detection, which significantly reduced the sensor volume and cost. The detailed detection principle was described, and a theoretical model was established to verify the effectiveness of the technique. Experiments were carried out to obtain the device's sensing performances. An Allan deviation analysis yielded a minimum detection limit of 0.054% for 1 s integration time that can be further improved to 0.009% at ~60 s. Finally, the reliability and anti-interference capability of the sensor system were verified by the atmospheric O2 monitoring. [ABSTRACT FROM AUTHOR]
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- 2023
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32. The hypoxia-driven crosstalk between tumor and tumor-associated macrophages: mechanisms and clinical treatment strategies
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Ruixue Bai, Yunong Li, Lingyan Jian, Yuehui Yang, Lin Zhao, and Minjie Wei
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Hypoxia-inducible factor ,Oxygen sensor ,Intercellular communication ,Inhibitor ,Neoplasms. Tumors. Oncology. Including cancer and carcinogens ,RC254-282 - Abstract
Abstract Given that hypoxia is a persistent physiological feature of many different solid tumors and a key driver for cancer malignancy, it is thought to be a major target in cancer treatment recently. Tumor-associated macrophages (TAMs) are the most abundant immune cells in the tumor microenvironment (TME), which have a large impact on tumor development and immunotherapy. TAMs massively accumulate within hypoxic tumor regions. TAMs and hypoxia represent a deadly combination because hypoxia has been suggested to induce a pro-tumorigenic macrophage phenotype. Hypoxia not only directly affects macrophage polarization, but it also has an indirect effect by altering the communication between tumor cells and macrophages. For example, hypoxia can influence the expression of chemokines and exosomes, both of which have profound impacts on the recipient cells. Recently, it has been demonstrated that the intricate interaction between cancer cells and TAMs in the hypoxic TME is relevant to poor prognosis and increased tumor malignancy. However, there are no comprehensive literature reviews on the molecular mechanisms underlying the hypoxia-mediated communication between tumor cells and TAMs. Therefore, this review has the aim to collect all recently available data on this topic and provide insights for developing novel therapeutic strategies for reducing the effects of hypoxia.
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- 2022
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33. Islet-on-a-chip device reveals first phase glucose-stimulated respiration is substrate limited by glycolysis independent of Ca2+ activity.
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Romario Regeenes, Yufeng Wang, Anthony Piro, Aaron Au, Christopher M. Yip, Michael B. Wheeler, and Jonathan V. Rocheleau
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Islet-on-a-chip ,Microfluidics ,Mouse pancreatic islets ,Oxygen consumption rate ,Oxygen sensor ,PKM2 ,Biotechnology ,TP248.13-248.65 - Abstract
Pancreatic islets respond metabolically to glucose by closing KATP channels resulting in Ca2+-influx and insulin secretion. Previous work has revealed the importance of glycolytic flux in triggering insulin secretion. However, it is unclear whether the triggered (‘first phase’) secretion is further amplified by Ca2+-stimulation of mitochondrial NADH production and/or oxidative phosphorylation (OxPhos). Although commercially available tools have been developed to explore islet metabolism, these methods often overlook islet variability and have poor spatiotemporal resolution. To tease apart first phase glucose-stimulated respiration, we designed an islet-on-a-chip microfluidic device to simultaneously measure O2-consumption rate (OCR) and Ca2+-activity of individual islets with high temporal resolution. We used finite element analysis to optimize placement of sensor in optically clear microwells on a thin glass coverslip. The microfluidic channels were subsequently fabricated using O2-impermeable plastic to limit outside-in diffusion and push islets against the microsensor. We validated our device using living mouse islets and well-established modulators of respiration. By inhibiting glycolysis and mitochondrial pyruvate transport, we show that islet OxPhos is limited by NADH-substrate rather than ADP in low and high glucose. We subsequently imaged glucose-stimulated OCR and Ca2+-influx simultaneously to reveal a biphasic respiratory response that is determined by glycolytic flux through pyruvate kinase (PKM2) and independent of Ca2+. These data demonstrate the unique utility of our modular and optically clear O2-sensor to simultaneously measure glucose-stimulated OCR and Ca2+ activity of multiple individual islets.
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- 2023
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34. Indirect Calorimetry in Spontaneously Breathing, Mechanically Ventilated and Extracorporeally Oxygenated Patients: An Engineering Review.
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Priem, Sebastiaan, Jonckheer, Joop, De Waele, Elisabeth, and Stiens, Johan
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VENTILATION , *ARTIFICIAL respiration , *EXTRACORPOREAL membrane oxygenation , *CALORIMETRY , *CARBON dioxide detectors , *RESPIRATION - Abstract
Indirect calorimetry (IC) is considered the gold standard for measuring resting energy expenditure (REE). This review presents an overview of the different techniques to assess REE with special regard to the use of IC in critically ill patients on extracorporeal membrane oxygenation (ECMO), as well as to the sensors used in commercially available indirect calorimeters. The theoretical and technical aspects of IC in spontaneously breathing subjects and critically ill patients on mechanical ventilation and/or ECMO are covered and a critical review and comparison of the different techniques and sensors is provided. This review also aims to accurately present the physical quantities and mathematical concepts regarding IC to reduce errors and promote consistency in further research. By studying IC on ECMO from an engineering point of view rather than a medical point of view, new problem definitions come into play to further advance these techniques. [ABSTRACT FROM AUTHOR]
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- 2023
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35. 两种水稻种子处理悬浮剂对旱直播水稻生长的影响.
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张艺璇, 谭静, 管俊娇, 奎丽梅, 胡茂林, 程 卯, 张 婷, 殷长生, 谷安宇, and 李小林
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RICE seeds , *UPLAND rice , *ARID regions , *RICE drying , *CLOTHIANIDIN , *SEED treatment , *HYBRID rice , *SEEDS - Abstract
In order to explore the effect of rice seed treatment suspension (FS) on the growth of rice in dry land cultivation. In this paper, two seed treatment suspensions, i.e., sedaxane + pylocyanonitrile + metalaxyl 11% FS and clothianidin 18% FS were selected to treat rice seed (guang8you 1973). The effect of FS was assessed by standard germination, Q2 test, agronomic traits and yield. The results showed that: under laboratory conditions, germination vigor, germination percentage and increased metabolism time (IMT) of two FS with the 1 : 50 treatment (1 mL of agent is required to process 50 g of seeds, referred to as the ratio of FS to seed) had no significant effect on these parameter compare with the blank control under laboratory condition. However, the FS with the 1 : 50 treatment showed a shorter relative germination time (RGT), a higher starting metabolism rate (SMR), and the oxygen metabolism rate (OMR) was significantly higher than that of the blank control by 1.33% and 1.38% per hour, respectively. This results indicate that FS can improve seed respiration and seed vigor. The comparison between the two FS indicate that the clothianidin 18% FS had a better effect on seed vigor than the sedaxane + pylocyanonitrile + metalaxyl 11% FS under the field condition. The field performance was better than that of the blank control, among which the seedling rate of seed coatingagent treatment increased by 27.60%-33.20% compared with CK, the number of tillers increased by 71.14-97.82 per hectare, the plant height increased by 4.90-6.80 cm, the thousand-grain weight increased by 7.27%-9.09%, the effective panicle increased by 9.45-13.42 million panicles per hectare, and the actual yield increased by 529.85 kg/hm2 and 580.70 kg/hm2, and there were significant differences between them. The results showed that: coating rice seeds with sedaxane + pylocyanonitrile + metalaxyl 11% FS and clothianidin 18% FS at a seed ratio of 1 : 50 can effectively promote rice seed respiration, improve the performance and yield in dry land cultivation. [ABSTRACT FROM AUTHOR]
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- 2023
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36. The Cys/N-degron pathway in the ubiquitin–proteasome system and autophagy.
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Heo, Ah Jung, Ji, Chang Hoon, and Kwon, Yong Tae
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AUTOPHAGY , *GENETIC code , *N-terminal residues , *POST-translational modification , *PROTEASOMES , *CHEMICAL properties , *REACTIVE oxygen species - Abstract
The N-degron pathway is a degradative system in which the N-terminal residues of proteins modulate the half-lives of proteins and other cellular materials. The majority of amino acids in the genetic code have the potential to induce cis or trans degradation in diverse processes, which requires selective recognition between N-degrons and cognate N-recognins. Of particular interest is the Cys/N-degron branch, in which the N-terminal cysteine (Nt-Cys) induces proteolysis via either the ubiquitin (Ub)–proteasome system (UPS) or the autophagy–lysosome pathway (ALP), depending on physiological conditions. Recent studies provided new insights into the central role of Nt-Cys in sensing the fluctuating levels of oxygen and reactive oxygen species (ROS). Here, we discuss the components, regulations, and functions of the Cys/N-degron pathway. All 20 amino acids can serve as N-degrons, directly or through post-translational modifications, when exposed at the protein N termini, providing a means for degrading all cellular proteins. Nt-Arg is a common element in the N-degrons generated from post-translational modifications of Cys as well as Asn, Gln, Asp, and Glu at the N termini. The resulting N-degrons are differentially recognized by a set of N-recognins for proteolysis via either the UPS or autophagy. The N-degron Cys mediates O 2 -dependent proteolysis through its oxidation and arginylation, which generates two structurally distinct N-degrons, leading to proteolysis by either the UPS or autophagy. Mammals and plants employ this unique chemical property of Nt-Cys to sense and react to acute and chronic hypoxia as well as oxidative stress by adjusting cellular concentrations of proteins carrying the N-degron Cys. [ABSTRACT FROM AUTHOR]
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- 2023
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37. Sensing characteristics of a limiting current oxygen sensor with (8YSZ)0.85(Cr2O3)0.15 dense diffusion barrier.
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Qi, Min, Wang, Xiangnan, Shu, Hui, and Dong, Yihang
- Abstract
(8YSZ)
1−x (Cr2 O3 )x (x = 0, 0.05, 0.10, 0.15) are prepared by the co-precipitation method. Diffraction peaks of the samples belonged to the cubic fluorite structure. Conductivity decreases first and then increases with increasing Cr2 O3 content. An oxygen sensor based on 8YSZ solid electrolyte and (8YSZ)0.85 (Cr2 O3 )0.15 diffusion barrier is prepared by the Pt slurry bonding method. The sensor has a limiting current plateau at 2% oxygen concentrations within 720 ~ 870 °C. The oxygen sensor has a linear relationship between the log IL and 1000/T. At 850 °C, a linear relationship between the limiting current IL and oxygen concentration x(O2 ) is established for the oxygen sensor. The oxygen sensor is provided with a limiting current plateau within the experimental concentration division, and the limiting current plateau is not affected by x(CO2 ) and p(H2 O). I-V curves of the oxygen sensor overlap, and the limiting current plateaus are almost equal under the long-term high-temperature operating conditions of 144 h. [ABSTRACT FROM AUTHOR]- Published
- 2023
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38. Effect of Oxygen on Water Vapor Oxidation of Fe by Oxygen Partial Pressure Control Using Gas Sensor.
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Fukumoto, Michihisa and Nakajima, Kano
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WATER vapor , *OXIDATION of water , *GAS detectors , *OXYGEN in water , *PARTIAL pressure , *OXYGEN , *OXIDATION - Abstract
An oxygen pump sensor was installed in front of an oxidation furnace to supply and discharge oxygen to the Ar–H2O atmosphere and accurately control the oxygen partial pressure in the atmosphere. Furthermore, the oxidation rate was set after the oxidation furnace. It was measured by an oxygen sensor and a hydrogen sensor. Pure iron was used as the sample. The purpose of this study was to clarify the oxidation behavior of water vapor and oxygen. As a result, it was clarified that the amount of hydrogen generated by the oxidation of water vapor and Fe decreases when oxygen is supplied. In addition, when the oxygen supply amount increased, oxidation by the water vapor did not occur. On the other hand, it was clarified that when oxygen in the atmosphere is discharged, oxidation by oxygen is suppressed and only oxidation by the water vapor occurs. In the cross-sectional microstructure after oxidation, Fe3O4 was formed in the outer layer in the environment where the oxygen was discharged, but by supplying oxygen, the oxide layer became thicker and Fe2O3 was formed in the outer layer. The mass gain increased as the oxygen was supplied. Considering the ratio of oxidation by water vapor and oxidation by oxygen, it was clarified by this method that the mass gain is greater when the oxidation by oxygen is dominant. [ABSTRACT FROM AUTHOR]
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- 2023
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39. Effects of oxygen volume fraction, temperature and diffusion layer thickness on the sensing characteristics of limiting current oxygen sensor.
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Li, Dongliang, Wang, Xiangnan, and Sun, Xiaoming
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OXYGEN detectors , *DIFFUSION barriers , *FICK'S laws of diffusion , *SOLID electrolytes , *PHYSICAL constants - Abstract
Oxygen sensors are prepared by Pt paddle bonding method with dense diffusion barrier of short-circuited yttria-stabilized zirconia (YSZ) solid electrolyte. Different from the previous normal diffusion and Knudsen diffusion mechanisms, the limiting current equation of this type oxygen sensor is derived based on the diffusion of oxygen ions in the dense diffusion barrier. The effects of oxygen volume fraction, temperature and diffusion layer thickness on the limiting current density are investigated. The relationship between the physical quantities in the experiment is consistent with the derived equation. [ABSTRACT FROM AUTHOR]
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- 2024
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40. Influence of solid electrolyte material selection on electromotive force characteristics of oxygen sensor for lead-cooled fast reactor.
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Tu, Xu, Zhu, Huiping, Wu, Weihao, Wang, Xikun, Guo, Zhangpeng, Wang, Tian, Li, Wenxuan, Yang, Lingfeng, Liang, Ruixian, Li, Hui, Hao, Zulong, Niu, Fenglei, and Liu, Fang
- Subjects
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ELECTROMOTIVE force , *CONDUCTIVITY of electrolytes , *YTTRIA stabilized zirconium oxide , *SOLID electrolytes , *OXYGEN detectors - Abstract
Potentiometric oxygen sensors play a crucial role in measuring dissolved oxygen concentration in lead-cooled fast reactors (LFRs). The choice of the solid electrolyte material, including yttria partially stabilized zirconia (YPSZ) and yttria stabilized zirconia (YSZ), exerts a significant influence on the sensors' performance characteristics. In this study, the Potentiometric oxygen sensors with YPSZ and YSZ solid electrolyte were tested within the oxygen-saturated lead-bismuth eutectic (LBE) at the temperature range from 473 K to 773 K. The ionic conductivities of the solid electrolytes were obtained by alternating current impedance. The crystal phase changes of YSZ and YPSZ were compared by variable temperature XRD. Notably, the oxygen ion channels begin to form in solid electrolytes at 523 K, with full activation occurring at 643 K for YSZ and 723 K for YPSZ. The electromotive force (EMF) of YSZ and YPSZ-sensors possess good accuracy and stability between 623 and 773 K. Below 623 K, the EMF of YPSZ-sensor is consistently deviated from the theoretical value. These variations in activation temperatures are attributed to differences in Y3+ content, resulting in distinct operational temperature ranges for electrolytes. [ABSTRACT FROM AUTHOR]
- Published
- 2024
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41. Oxygen transport mechanism and the effect of microstructure on the oxygen response behavior of an oxygen-sensitive composite Ce0.9Gd0.1O2-ẟ – La0.6Sr0.4FeO3-ẟ at high temperature.
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Das, Subhadip and Pratihar, Swadesh Kumar
- Subjects
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FUEL cell electrolytes , *X-ray photoelectron spectroscopy , *OXYGEN detectors , *CERIUM oxides , *GAS detectors - Abstract
Compositions like gadolinium doped cerium oxide Ce 0.9 Gd 0.1 O 2-ẟ and strontium doped lanthanum ferrite La 0.6 Sr 0.4 FeO 3-ẟ, or their composites are well known in the field of fuel cell electrolyte, oxygen transporting membrane and catalytic reactor applications. This work offers insight into composite material's oxygen response characteristics, taking Ce 0.9 Gd 0.1 O 2-ẟ and La 0.6 Sr 0.4 FeO 3-ẟ in 70: 30 wt percent. One pot sol-gel method was employed for the powder synthesis. The powder was characterized by TG-DSC, XRD, Raman spectroscopy, and X-ray photoelectron spectroscopy (XPS). FESEM-EDX and EDX-line profiling techniques were used to check the compositional homogeneity of sintered bodies. Oxygen response tests were conducted from ambient (20 % O 2) to 100 % O 2 concentration, using bulk samples sintered at three different temperatures, i.e., 1000, 1150, and 1250 °C at a fixed soaking time of 4 hours. The sintered specimens' apparent porosity, bulk density, surface morphology, and electrical conductivity were also examined. The sintering temperature significantly impacts response behavior as the porosity and grain size of the sintered body plays a vital role in sensing performance. The mechanism of response towards oxygen is also discussed. Sample 73–100 displayed the best performance among others. We achieved the lowest response and recovery time of 15 – 48 sec and 45 – 80 sec from a 0.60 mm thick bulk material at 950 °C. Harsh environments were intentionally created to check the reliability and reproducibility of the response data. This material could be a good candidate as an oxygen gas sensor at high temperatures owing to its good sensitivity, reliability, reversibility, and stability. [Display omitted] • Studied oxygen response properties of bulk 70 Ce 0.9 Gd 0.1 O 2-∂ - 30 La 0.6 Sr 0.4 FeO 3-∂ nanocomposite. • Oxygen response has been evaluated for the test specimens having varying porosity and grain size. • Lowest response and recovery time of 15 s and 45 s achieved at the test temperature of 950℃. [ABSTRACT FROM AUTHOR]
- Published
- 2024
- Full Text
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42. IMSIS: An instrumented microphysiological system with integrated sensors for monitoring cellular metabolic activities.
- Author
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Cheng, Ming-Hao, Way, Ryan, Fresa, Kyle, Catandi, Giovana D., Carnevale, Elaine, Chicco, Adam J., and Chen, Thomas W.
- Subjects
- *
MICROPHYSIOLOGICAL systems , *GRAPHICAL user interfaces , *OXYGEN detectors , *HYDROGEN detectors , *ELECTROCHEMICAL sensors , *BIOELECTRONICS - Abstract
Well plates are widely used in biological experiments, particularly in pharmaceutical sciences and cell biology. Its popularity stems from its versatility to support a variety of fluorescent markers for high throughput monitoring of cellular activities. However, using fluorescent markers in traditional well plates has its own challenges, namely, they can be potentially toxic to cells, and thus, may perturb their biological functions; and it is difficult to monitor multiple analytes concurrently and in real-time inside each well. This paper presents a fully instrumented microphysiological system with integrated sensors (IMSIS) with a similar well format. Each well in the microphysiological system has a set of sensors for monitoring multiple metabolic analytes in real-time. The IMSIS platform is supported by integrated bioelectronic circuits and a graphical user interface for easy user configuration and monitoring. The system has integrated microfluidics to maintain its microphysiological environment within each well. The IMSIS platform currently incorporates O 2 , H 2 O 2 , and pH sensors inside each well, allowing up to six wells to perform concurrent measurements in real-time. Furthermore, the architecture is scalable to achieve an even higher level of throughput. The miniaturized design ensures portability, suitable for small offices and field applications. The IMSIS platform was successfully used to monitor in real-time the mitochondrial functions of live bovine embryos in O 2 consumption, H 2 O 2 release as an indication of ROS production, and extracellular acidity changes before and after the introduction of external substrates. [ABSTRACT FROM AUTHOR]
- Published
- 2024
- Full Text
- View/download PDF
43. Role of prolyl hydroxylase domain proteins in bone metabolism
- Author
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David Wolf, Aruljothi Muralidharan, and Subburaman Mohan
- Subjects
Bone ,Prolyl hydroxylase domain ,Hypoxia-inducible factor ,Bone regeneration ,Oxygen sensor ,Epigenetic regulation ,Diseases of the musculoskeletal system ,RC925-935 - Abstract
Cellular metabolism requires dissolved oxygen gas. Because evolutionary refinements have constrained mammalian dissolved oxygen levels, intracellular oxygen sensors are vital for optimizing the bioenergetic and biosynthetic use of dissolved oxygen. Prolyl hydroxylase domain (PHD) homologs 1–3 (PHD1/2/3) are molecular oxygen dependent non-heme dioxygenases whose enzymatic activity is regulated by the concentration of dissolved oxygen. PHD oxygen dependency has evolved into an important intracellular oxygen sensor. The most well studied mechanism of PHD oxygen-sensing is its regulation of the hypoxia-inducible factor (HIF) hypoxia signaling pathway. Heterodimeric HIF transcription factor activity is regulated post-translationally by selective PHD proline hydroxylation of its HIF1α subunit, accelerating HIF1α ubiquitination and proteasomal degradation, preventing HIF heterodimer assembly, nuclear accumulation, and activation of its target oxygen homeostasis genes. Phd2 has been shown to be the key isoform responsible for HIF1α subunit regulation in many cell types and accordingly disruption of the Phd2 gene results in embryonic lethality. In bone cells Phd2 is expressed in high abundance and tightly regulated. Conditional disruption of the Phd1, Phd2 and/or Phd3 gene in various bone cell types using different Cre drivers reveals a major role for PHD2 in skeletal growth and development. In this review, we will summarize the state of current knowledge on the role and mechanism of action of PHD2 as oxygen sensor in regulating bone metabolism.
- Published
- 2022
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- View/download PDF
44. Effects of fuel injection system and exhaust gas catalytic treatments on PAH emissions from motorcycles.
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Lin, Sheng-Lun, Zhang, Hongjie, Wang, Lin-Chi, Lee, Yen-Yi, and Huang, Chien-Er
- Subjects
WASTE gases ,EXHAUST systems ,FUEL systems ,MOTORCYCLES ,MOTORCYCLING ,POLYCYCLIC aromatic hydrocarbons - Abstract
The motorcycles are unignorable near-ground pollutant emission sources that increase the human exposure in the dense area. However, the information of the polycyclic aromatic hydrocarbons (PAHs) emissions under different scenarios of engine and emission control for motorcycle is limited. This study focused on the PAH emissions from two fuel-injection types of motorcycles, including the premixed fuel-injection (PFi) with carburetor and electronic fuel-injection (EFi). Specifically, the effects of throttle opening (TO), secondary air system (SAS), oxygen sensor (OS), oxidation catalytic converter (OCC), and three-way catalytic converter (TWC) on PAH emissions are investigated. Results show that the PAH emission concentrations increase 227–727%, 351–492%, and 155–408% by the increasing TO ratio, unworking SAS, and OS units in both motorcycles. For the PFi engine, the OCC unit is found to be more effective in PAH control (31–89%) than the SAS system (72–80%), especially under low TO operation. For the EFi engine which dominates the motorcycle market recently, the oxygen sensor for more accurate combustion control shows a better PAH reduction (36–76%) than TWC system (21–66%). The ultra-fine particulate phase PAHs, which is hardly removed by catalyst, needs to be further considered. Moreover, the total PAH emission level of the EFi engine is still about ten times higher than that of the PFi. By the annual emission calculation for three densely populated countries, the recent evolution significantly reduces the annual hydrocarbon (HC), carbon monoxide (CO), and nitrogen oxide (NOx) emissions but have unignorable PAH emissions. These emissions continuously affect the human health in the near-ground urban air and need to be considered in the next generation of motorcycle design. [ABSTRACT FROM AUTHOR]
- Published
- 2023
- Full Text
- View/download PDF
45. Study on the Deterioration Mechanism of Pb on TiO 2 Oxygen Sensor.
- Author
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Duan, Chao, Zhang, Lejun, Wu, Zhaoxi, Wang, Xu, Meng, Meng, and Zhang, Maolin
- Subjects
OXYGEN detectors ,TITANIUM dioxide ,STEADY-state responses ,WASTE gases ,GAS absorption & adsorption ,AUTOMOBILE emissions ,PETROLEUM as fuel ,ACTIVATION energy - Abstract
Previous studies have shown that the pollutants in exhaust gas can cause performance deterioration in air-fuel oxygen sensors. Although the content of Pb in fuel oil is as low as 5 mg/L, the effect of long-term Pb accumulation on TiO
2 oxygen sensors is still unclear. In this paper, the influence mechanism of Pb-containing additives in automobile exhaust gas on the response characteristics of TiO2 oxygen sensors was simulated and studied by depositing Pb-containing pollutants on the surface of a TiO2 sensitive film. It was found that the accumulation of Pb changed the surface gas adsorption state and reduced the activation energy of TiO2 , thus affecting the steady-state response voltage and response speed of the TiO2 -based oxygen sensor. [ABSTRACT FROM AUTHOR]- Published
- 2023
- Full Text
- View/download PDF
46. NIR Luminescent Oxygen-Sensing Nanoparticles for Continuous Glucose and Lactate Monitoring.
- Author
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Soundaram Jeevarathinam, Ananthakrishnan, Saleem, Waqas, Martin, Nya, Hu, Connie, and McShane, Michael J.
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LACTATES ,ETHYLCELLULOSE ,GLUCOSE ,OXYGEN detectors ,GLUCOSE oxidase ,LACTATION ,BIOLOGICAL systems - Abstract
A highly sensitive, biocompatible, and scalable phosphorescent oxygen sensor formulation is designed and evaluated for use in continuous metabolite sensors for biological systems. Ethyl cellulose (EC) and polystyrene (PS) nanoparticles (NPs) stabilized with Pluronic F68 (PF 68), Polydimethylsiloxane-b-polyethyleneglycol methyl ether (PDMS-PEG), sodium dodecylsulfate (SDS), and cetyltimethylammonium bromide (CTAB) were prepared and studied. The resulting NPs with eight different surfactant–polymer matrix combinations were evaluated for physical properties, oxygen sensitivity, effect of changes in dispersion matrix, and cytotoxicity. The EC NPs exhibited a narrower size distribution and 40% higher sensitivity than PS, with Stern–Volmer constants (K
sv ) 0.041–0.052 µM−1 for EC, compared to 0.029–0.034 µM−1 for PS. Notably, ethyl cellulose NPs protected with PF68 were selected as the preferred formulation, as they were not cytotoxic towards 3T3 fibroblasts and exhibited a wide phosphorescence lifetime response of >211.1 µs over 258–0 µM and ~100 µs over 2.58–0 µM oxygen, with a limit of detection (LoD) of oxygen in aqueous phase of 0.0016 µM. The EC-PF68 NPs were then efficiently encapsulated in alginate microparticles along with glucose oxidase (GOx) and catalase (CAT) to form phosphorescent nanoparticles-in-microparticle (NIMs) glucose sensing microdomains. The fabricated glucose sensors showed a sensitivity of 0.40 µs dL mg−1 with a dynamic phosphorescence lifetime range of 46.6–197.1 µs over 0–150 mg dL−1 glucose, with a glucose LoD of 18.3 mg dL−1 and maximum distinguishable concentration of 111.1 mg dL−1 . Similarly, lactate sensors were prepared with NIMs microdomains containing lactate oxidase (LOx) and found to have a detection range of 0–14 mg dL−1 with LoD of 1.8 mg dL−1 and maximum concentration of 13.7 mg dL−1 with lactate sensitivity of 10.7 µs dL mg−1 . Owing to its versatility, the proposed NIMs-based design can be extended to a wide range of metabolites and different oxygen-sensing dyes with different excitation wavelengths based on specific application. [ABSTRACT FROM AUTHOR]- Published
- 2023
- Full Text
- View/download PDF
47. Medical Oxygen Sensor Based on Acoustic Resonance Frequency Tracking Using FPGA.
- Author
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Wang, Jianwei, Chen, Mingyang, Chen, Qianqian, and Wang, Huili
- Abstract
The aim of this study is to develop a noninvasive medical oxygen sensor using the acoustic resonance frequency tracking technique. To make it realize, the optimization of sound-resonance cavity based on an acoustic longitudinal mode is used as the sensing element for this sensor. A new method for resonance frequency tracking is presented by the phase difference comparison and calculation. Based on the relationships among the excitation and response signals of the sound-resonance cavity, the phase difference comparison and calculation algorithm had been used to automatically track the resonance frequency. The resonance frequency tracking is implemented by the field-programmable gate array (FPGA) device. The performance of the sensor is demonstrated by measuring the concentration of oxygen. The test results show that a sensitivity limit of 1000 ppm, a response time of 4 s, and detection capabilities over a broad concentration range from 1000 ppm to 100% have been demonstrated at one atmosphere. Results demonstrate that this work is expected to provide a new technical means for medical oxygen monitoring. [ABSTRACT FROM AUTHOR]
- Published
- 2022
- Full Text
- View/download PDF
48. Scanning Tissue Oxygen Needle Probe
- Author
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Ashkenazi, S., Cho, D., Song, C. W., Crusio, Wim E., Series Editor, Dong, Haidong, Series Editor, Radeke, Heinfried H., Series Editor, Rezaei, Nima, Series Editor, Steinlein, Ortrud, Series Editor, Xiao, Junjie, Series Editor, Nemoto, Edwin M., editor, Harrison, Eileen M., editor, Pias, Sally C., editor, Bragin, Denis E., editor, Harrison, David K., editor, and LaManna, Joseph C., editor
- Published
- 2021
- Full Text
- View/download PDF
49. IoT Healthcare Applications
- Author
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Lingam, Sunitha, Fortino, Giancarlo, Series Editor, Liotta, Antonio, Series Editor, Siarry, Patrick, editor, Jabbar, M.A., editor, Aluvalu, Rajanikanth, editor, Abraham, Ajith, editor, and Madureira, Ana, editor
- Published
- 2021
- Full Text
- View/download PDF
50. Method for Assessing Performance of Catalytic Converter of Spark-Ignition Car Engine in Operating Conditions
- Author
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Ivanov, A. K., Abyzov, O. V., Galyshev, Yu. V., Cavas-Martínez, Francisco, Series Editor, Chaari, Fakher, Series Editor, Gherardini, Francesco, Series Editor, Haddar, Mohamed, Series Editor, Ivanov, Vitalii, Series Editor, Kwon, Young W., Series Editor, Trojanowska, Justyna, Series Editor, di Mare, Francesca, Series Editor, Radionov, Andrey A., editor, and Gasiyarov, Vadim R., editor
- Published
- 2021
- Full Text
- View/download PDF
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