Synthesis Characterization of Nanostructured ZnCo2O4 with High Sensitivity to CO Gas

Carbon monoxide (CO) is very toxic to health. CO gas can cause intoxication and even death when the concentration is high or there are long exposure times. To detect atmospheres with CO gas concentration detectors are placed. In this work, a novel CO detection device was proposed and applied for CO detection. For its implementation, four stages were developed: Synthesis of nickel antimonite (NiSb2O6) oxide powders, physical characterization of NiSb2O6 powders, Pellet fabrication and sensitivity test in CO atmospheres and electronic circuit implementation where signal adaptation and signal amplification were considered. Experimentally, a chemical sensor was built and characterized, its signal adaptation circuit was implemented and also it was proved using CO concentrations from 1 to 300 ppm with the operating temperatures of 100, 200, and 300 °C. Its optimal operation was at 300 °C. From the experimental results, the CO detection device had excellent functionality because the chemical sensor based on the nickel antimonite oxide had high sensitivity and good electrical response, whereas the DC electronic circuit had good performance.

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Design, Fabrication and Characterization of a Low-Power Gas Sensor with High Sensitivity to CO Gas

Journal of the Korean Physical Society ◽

10.3938/jkps.51.2069 ◽

2007 ◽

Vol 51 (6) ◽

pp. 2069 ◽

Cited By ~ 18

Author(s):

Si-Dong Kim ◽

Bum-Joon Kim ◽

Jin-Ho Yoon ◽

Jung-Sik Kim

Keyword(s):

Low Power ◽

Gas Sensor ◽

High Sensitivity ◽

Fabrication And Characterization ◽

Co Gas

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Ultrastructural identification of three types of sensory setae on copepod antennae

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100141159 ◽

1995 ◽

Vol 53 ◽

pp. 956-957

Author(s):

T. M. Weatherby ◽

P.H. Lenz

Keyword(s):

Phase Locking ◽

Membrane Surface ◽

Reaction Times ◽

High Sensitivity ◽

Structural Features ◽

Calanoid Copepods ◽

Marine Food Webs ◽

Dendritic Membrane ◽

Ultrastructural Characterization

Crustaceans, as well as other arthropods, are covered with sensory setae and hairs, including mechanoand chemosensory sensillae with a ciliary origin. Calanoid copepods are small planktonic crustaceans forming a major link in marine food webs. In conjunction with behavioral and physiological studies of the antennae of calanoids, we undertook the ultrastructural characterization of sensory setae on the antennae of Pleuromamma xiphias.Distal mechanoreceptive setae exhibit exceptional behavioral and physiological performance characteristics: high sensitivity (<10 nm displacements), fast reaction times (<1 msec latency) and phase locking to high frequencies (1-2 kHz). Unusual structural features of the mechanoreceptors are likely to be related to their physiological sensitivity. These features include a large number (up to 3000) of microtubules in each sensory cell dendrite, arising from or anchored to electron dense rods associated with the ciliary basal body microtubule doublets. The microtubules are arranged in a regular array, with bridges between and within rows. These bundles of microtubules extend far into each mechanoreceptive seta and terminate in a staggered fashion along the dendritic membrane, contacting a large membrane surface area and providing a large potential site of mechanotransduction.

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Average fractional polarization of extragalactic sources at Planck frequencies

Astronomy and Astrophysics ◽

10.1051/0004-6361/201732342 ◽

2018 ◽

Vol 618 ◽

pp. A29 ◽

Cited By ~ 6

Author(s):

T. Trombetti ◽

C. Burigana ◽

G. De Zotti ◽

V. Galluzzi ◽

M. Massardi

Keyword(s):

High Sensitivity ◽

Point Sources ◽

Distribution Analysis ◽

Microwave Background ◽

Residual Noise ◽

Upper Limits ◽

Dusty Galaxies ◽

Using Data ◽

Polarization Fraction

Recent detailed simulations have shown that an insufficiently accurate characterization of the contamination of unresolved polarized extragalactic sources can seriously bias measurements of the primordial cosmic microwave background (CMB) power spectrum if the tensor-to-scalar ratio r ∼ 0.001, as predicted by models currently of special interest (e.g., Starobinsky’s R2 and Higgs inflation). This has motivated a reanalysis of the median polarization fraction of extragalactic sources (radio-loud AGNs and dusty galaxies) using data from the Planck polarization maps. Our approach, exploiting the intensity distribution analysis, mitigates or overcomes the most delicate aspects of earlier analyses based on stacking techniques. By means of simulations, we have shown that the residual noise bias on the median polarization fraction, Πmedian, of extragalactic sources is generally ≲0.1%. For radio sources, we have found Πmedian ≃ 2.83%, with no significant dependence on either frequency or flux density, in good agreement with the earlier estimate and with high-sensitivity measurements in the frequency range 5–40 GHz. No polarization signal is detected in the case of dusty galaxies, implying 90% confidence upper limits of Πdusty ≲ 2.2% at 353 GHz and of ≲3.9% at 217 GHz. The contamination of CMB polarization maps by unresolved point sources is discussed.

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Complex Permittivity Characterization of Liquid Samples Based on a Split Ring Resonator (SRR)

Sensors ◽

10.3390/s21103385 ◽

2021 ◽

Vol 21 (10) ◽

pp. 3385

Author(s):

Jialu Ma ◽

Jingchao Tang ◽

Kaicheng Wang ◽

Lianghao Guo ◽

Yubin Gong ◽

...

Keyword(s):

Resonant Frequency ◽

Complex Permittivity ◽

Ring Resonator ◽

High Sensitivity ◽

Split Ring Resonator ◽

Debye Model ◽

Split Ring ◽

Liquid Samples ◽

Microwave Sensor

A complex permittivity characterization method for liquid samples has been proposed. The measurement is carried out based on a self-designed microwave sensor with a split ring resonator (SRR), the unload resonant frequency of which is 5.05 GHz. The liquid samples in capillary are placed in the resonant zone of the fabricated senor for high sensitivity measurement. The frequency shift of 58.7 MHz is achieved when the capillary is filled with ethanol, corresponding a sensitivity of 97.46 MHz/μL. The complex permittivity of methanol, ethanol, isopropanol (IPA) and deionized water at the resonant frequency are measured and calibrated by the first order Debye model. Then, the complex permittivity of different concentrations of aqueous solutions of these materials are measured by using the calibrated sensor system. The results show that the proposed sensor has high sensitivity and accuracy in measuring the complex permittivity of liquid samples with volumes as small as 0.13 μL. It provides a useful reference for the complex permittivity characterization of small amount of liquid chemical samples. In addition, the characterization of an important biological sample (inositol) is carried out by using the proposed sensor.

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Characterization of Piezoelectric Nanofiber Composites Acoustic Emission Sensor for Structure Health Monitoring

Volume 5: 6th International Conference on Micro- and Nanosystems; 17th Design for Manufacturing and the Life Cycle Conference ◽

10.1115/detc2012-71538 ◽

2012 ◽

Cited By ~ 1

Author(s):

Xi Chen ◽

Yong Shi

Keyword(s):

Acoustic Emission ◽

Lead Zirconate Titanate ◽

High Sensitivity ◽

Lead Zirconate ◽

Steel Bar ◽

Promising Application ◽

Soft Polymer ◽

Active Fiber Composites ◽

The Mathematical Model

A nanoscale active fiber composites (NAFCs) based acoustic emission (AE) sensor with high sensitivity is developed. The lead zirconate titanate (PZT) nanofibers, with the diameter of approximately 80 nm, were electrospun on a silicon substrate. Nanofibers were parallel aligned on the substrate under a controlled electric field. The interdigitated electrodes were deposited on the PZT nanofibers and packaged by spinning a thin soft polymer layer on the top of the sensor. The hysteresis loop shows a typical ferroelectric property of as-spun PZT nanofibers. The mathematical model of the voltage generation when the elastic waves were reaching the sensor was studied. The sensor was tested by mounting on a steel surface and the measured output voltage under the periodic impact of a grounded steel bar was over 35 mV. The small size of the developed PZT NAFCs AE sensor shows a promising application in monitoring the structures by integration into composites.

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