scholarly journals A New Inductive Debris Sensor Based on Dual-Excitation Coils and Dual-Sensing Coils for Online Debris Monitoring

Sensors ◽  
2021 ◽  
Vol 21 (22) ◽  
pp. 7556
Author(s):  
Xianwei Wu ◽  
Yinghong Zhang ◽  
Nian Li ◽  
Zhenghua Qian ◽  
Dianzi Liu ◽  
...  

Lubricants are of key importance for mechanical processing, and exist in nearly every mechanical system. When the equipment is in operation, debris particles will be generated in mechanical lubricants. The detection of debris particles can indicate the wear degree of machinery components, and provide prognosis warning for the system before the fault occurs. In this work, a novel type of inductive debris sensor consisting of two excitation coils and two sensing coils is proposed for online debris monitoring. The developed sensor was proven to be of high sensitivity through experimental verification. The testing results show that, using the designed sensor, ferrous metal debris with a size of 115 μm and nonferrous metal debris with a size of 313 μm in a pipe with an inner diameter of 12.7 mm can be effectively detected. Moreover, the proposed inductive debris sensor structure has better sensitivity at higher throughput and its design provides a useful insight into the development of high-quality sensors with superior performances.

Author(s):  
Seiji Isoda ◽  
Kimitsugu Saitoh ◽  
Sakumi Moriguchi ◽  
Takashi Kobayashi

On the observation of structures by high resolution electron microscopy, recording materials with high sensitivity and high quality is awaited, especially for the study of radiation sensitive specimens. Such recording material should be easily combined with the minimum dose system and cryoprotection method. Recently a new recording material, imaging plate, comes to be widely used in X-ray radiography and also in electron microscopy, because of its high sensitivity, high quality and the easiness in handling the images with a computer. The properties of the imaging plate in 100 to 400 kV electron microscopes were already discussed and the effectiveness was revealed.It is demanded to study the applicability of the imaging plate to high voltage electron microscopy. The quality of the imaging plate was investigated using an imaging plate system (JEOL EM-HSR100) equipped in a new Kyoto 1000kV electron microscope. In the system both the imaging plate and films can be introduced together into the camera chamber. Figure 1 shows the effect of accelerating voltage on read-out signal intensities from the imaging plate. The characteristic of commercially available imaging plates is unfortunately optimized for 100 to 200 keV electrons and then for 600 to 1000 keV electrons the signal is reduced. In the electron dose range of 10−13 to 10−10 C/cm2, the signal increases linearly with logarithm of electron dose in all acceralating volatges.


Author(s):  
Corrinne E Grover ◽  
Daojun Yuan ◽  
Mark A Arick ◽  
Emma R Miller ◽  
Guanjing Hu ◽  
...  

Abstract Cotton is an important textile crop whose gains in production over the last century have been challenged by various diseases. Because many modern cultivars are susceptible to several pests and pathogens, breeding efforts have included attempts to introgress wild, naturally resistant germplasm into elite lines. Gossypium stocksii is a wild cotton species native to Africa, which is part of a clade of vastly understudied species. Most of what is known about this species comes from pest resistance surveys and/or breeding efforts, which suggests that G. stocksii could be a valuable reservoir of natural pest resistance. Here we present a high-quality de novo genome sequence for G. stocksii. We compare the G. stocksii genome with resequencing data from a closely related, understudied species (G. somalense) to generate insight into the relatedness of these cotton species. Finally, we discuss the utility of the G. stocksii genome for understanding pest resistance in cotton, particularly resistance to cotton leaf curl virus.


Author(s):  
Ryohei Nakagawa ◽  
Zhi Wang ◽  
Ken Suzuki

Health monitoring devices using a strain sensor, which shows high sensitivity and large deformability, are strongly demanded due to further aging of society with fewer children. Conventional strain sensors, such as metallic strain gauges and semiconductive strain sensors, however, aren’t applicable to health monitoring because of their low sensitivity and deformability. In this study, fundamental design of area-arrayed graphene nano-ribbon (GNR) strain senor was proposed in order to fabricate next-generation strain sensor. The sensor was consisted of two sections, which are stress concentration section and stress detecting section. This structure can take full advantage of GNR’s properties. Moreover, high quality GNR fabrication process, which is one of the important process in the sensor, was developed by applying CVD (Chemical Vapor Deposition) method. Top-down approach was applied to fabricate the GNR. At first, in order to synthesize a high-quality graphene sheet, acetylene-based LPCVD (low pressure chemical vapor deposition) using a closed Cu foil was employed. After that, graphene was transferred silicon substrate and the quality was evaluated. The high quality graphene was transferred on the soft PDMS substrate and metallic electrodes were fabricated by applying MEMS technology. Area-arrayed fine pin structure was fabricated by using hard PDMS as a stress-concentration section. Finally, both sections were integrated to form a highly sensitive and large deformable pressure sensor. The strain sensitivity of the GNR-base sensor was also evaluated.


2021 ◽  
Author(s):  
Ahmed Mehaney ◽  
Hussein A. Elsayed ◽  
Ashour M. Ahmed

Abstract Detection of blood-carried volatile organic compounds (VOCs) existing in the exhaled breath of human is an attractive research point for noninvasive diagnosis of diseases. In this research, we introduce a novel application of photonic crystals (PCs) for the detection of isoprene traces in the exhaled breath as a biomarker for liver fibrosis. This idea is introduced for the first time according to the best of our knowledge. The proposed sensor structure is a one-dimensional (1D) PC constructed from a multilayer stack of two dielectric materials covered with an air cavity layer filled with the dry exhaled breath (DEB) and a thin metallic layer of Au is attached on the top surface. Hence, the proposed sensor is configured as, [prism/Au/air cavity/(GaN/SiO2)10]. The transfer matrix method and the Drude model are adopted to calculate the numerical simulations and reflection spectra of the design. The essential key for sensing isoprene levels is the resonant optical Tamm plasmon (TP) states within the photonic bandgap. The obtained numerical results are promising such as high sensitivity (S) of 0.321 nm/ppm or 278720 nm/RIU. This technique can be reducing the risk of infection during the taking of blood samples by syringe. Also, it can prevent the pain of patients. Finally, this work opens the door for the detection of many diseases by analyzing the breaths of patients based on photonic crystals.


2021 ◽  
Vol 30 (16) ◽  
pp. 956-962
Author(s):  
Malcolm Elliott

The assessment of vital signs is critical for safe, high-quality care. Vital signs' data provide valuable insight into the patient's condition, including how they are responding to medical treatment and, importantly, whether the patient is deteriorating. Although abnormal vital signs have been associated with poor clinical outcomes, research has consistently found that vital signs' assessment is often neglected in clinical practice. Factors contributing to this include nurses' knowledge, clinical judgement, culture, tradition and workloads. To emphasise the importance of vital signs' assessment, global elements of vital signs' assessment are proposed. The elements reflect key principles underpinning vital signs' assessment and are informed by evidence-based literature.


1973 ◽  
Vol 56 (6) ◽  
pp. 1496-1502
Author(s):  
Fred P Czech

Abstract The AOAC colorimetric acetylacetone method for formaldehyde in sugar products is optimized by means of the simplex experimental design process. The resultant method is almost 4 times as sensitive as the original AOAC method. It is about 33% more sensitive than the simplex optimized J-acid procedure and 45% more sensitive than the simplex optimized chromotropic acid method and, thus, represents one of the most sensitive methods now available. The average relative standard deviation is about ±2.7%. The limit of detectability is estimated to be 30 ppb. The didactic exposition of the simplex optimization process reported earlier is applied to the AOAC acetyl-acetone method. Further insights into simplex operations are provided and certain advantages of simplex application are pointed out. It is shown that, by sacrificing the high sensitivity of the optimized method the parameters of the new method result in about a 10-fold increase in analytical speed. Further application of kinetic considerations and the advantages of high quality, productivity, and economy in chemical analytical methods by means of the simplex experimental design process are described.


Sensors ◽  
2019 ◽  
Vol 19 (1) ◽  
pp. 188 ◽  
Author(s):  
Debo Wei ◽  
Jianyu Fu ◽  
Ruiwen Liu ◽  
Ying Hou ◽  
Chao Liu ◽  
...  

Micro-Pirani vacuum sensors usually operate at hundreds of microwatts, which limits their application in battery-powered sensor systems. This paper reports a diode-based, low power consumption micro-Pirani vacuum sensor that has high sensitivity. Optimizations to the micro-Pirani vacuum sensor were made regarding two aspects. On the one hand, a greater temperature coefficient was obtained without increasing power consumption by taking advantage of series diodes; on the other hand, the sensor structure and geometries were redesigned to enlarge temperature variation. After that, the sensor was fabricated and tested. Test results indicated that the dynamic vacuum pressure range of the sensor was from 10−1 to 104 Pa when the forward bias current was as low as 10 μA with a power consumption of 50 μW. Average sensitivity was up to 90 μV/Pa and the sensitivity of unit power consumption increased to 1.8 V/W/Pa. In addition, the sensor could also work at a greater forward bias current for better sensor performance.


2013 ◽  
Vol 441 ◽  
pp. 356-359
Author(s):  
Wei Wei ◽  
Hai Ying Jiang ◽  
Qin Jian Sun ◽  
Qiang Huang ◽  
Zhi Wei Wang

A small level measurement system is designed by installing a compact capacitive level sensor in the small container. By analyzing the capacitive sensor structure, a sensor measurement circuit is designed with high sensitivity, measuring stability and good repeatability. Capacitance measurement circuit makes use of multiple harmonic oscillation principle. The microcomputer measures the oscillation frequency of the multivibrator, and calculates the liquid level height based on the monotonic function about the liquid level height and frequency.


2020 ◽  
Vol 818 ◽  
pp. 152855 ◽  
Author(s):  
Ting Wang ◽  
Zhihua Xiong ◽  
Juanli Zhao ◽  
Ning Wu ◽  
Kun Du ◽  
...  

Author(s):  
S. V. Murali ◽  
F. K. Choy ◽  
J. Zhe ◽  
J. Carletta ◽  
X. Xia

This paper describes a capacitance sensing method to detect oil debris contents. Experimental investigations are conducted for both static and dynamic measurements. Static measurements are performed by inserting small metal wires into the oil sample between the two plate electrodes of a capacitor. With a gap of 7mm between the electrodes, it was found that the capacitance measurement can detect metal wires as small as 4 mils (101 μm) in diameter. While measurements of ferrous and the non-ferrous wires show certain measurable differences, a systematic difference between the two sets of measurements cannot be established. The dynamic measurements were conducted by measuring the changes in capacitance between two plate electrodes when a small particle was dropped into the oil between the two electrodes. The passage of a metal particle can be dynamically detected. It is expected that smaller metal debris particles can be detected by reducing the spacing between the two electrode plates in microchannels.


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