HIGH SENSITIVE HYDROGEN SENSOR BY Pd/OXIDE/InGaP MOS STRUCTURE

2006 ◽  
Vol 20 (28) ◽  
pp. 1781-1787
Author(s):  
KAO-FENG YARN
Keyword(s):  
Room Temperature ◽  
High Sensitivity ◽  
Hydrogen Sensor ◽  
Native Oxide ◽  
Output Current ◽  
High Hydrogen ◽  
Phase Oxidation ◽  
High Oxidation ◽  
Experimental Formation

Experimental formation of LPO (liquid phase oxidation)-grown InGaP native oxide near room temperature (~60° C ) is demonstrated. A high oxidation rate is obtained and checked by SEM and AES. The native oxide is determined to be composed of InPO 4 and Ga 2 O 3, analyzed by the results of XPS measurement. Due to the presence of the excellent quality of InGaP native oxide, high hydrogen ( H 2) sensitivity in output current of a Pd /oxide/ InGaP MOS Schottky diode is observed. Under the applied voltage of -1 V and 50 ppm H 2/air, a high sensitivity of 1090 is obtained. An obvious variation of output current and a short response time due to the exposure to different H 2 concentration are also achieved. For example, the adsorption (τa) and desorption (τb) time constants under 50 ppm H 2/air are 2.3 s and 2.7 s, respectively.

Pd/Oxide/InGaP MOS Schottky Hydrogen Sensor with Native Thin Oxide

2007 ◽  
Vol 121-123 ◽  
pp. 627-630
Author(s):  
Kao Feng Yarn ◽  
Y.L. Lin ◽  
M.C. Chure ◽  
K.K. Wu ◽  
S.C. Chang
Keyword(s):  
Room Temperature ◽  
High Sensitivity ◽  
Hydrogen Sensor ◽  
Native Oxide ◽  
Liquid Phase Deposition ◽  
Output Current ◽  
High Hydrogen ◽  
High Oxidation ◽  
First Time

Liquid phase deposition (LPD) grown InGaP native oxide near room temperature (~60oC) is demonstrated and investigated for the first time. A high oxidation rate (~80nm/hr) is obtained and checked by SEM and AES. The oxide is determined to be composed of InPO4 and Ga2O3 which are analyzed by the results of XPS measurement. Due to the presence of excellent quality of InGaP native oxide, high hydrogen (H2) sensitivity in output current of Pd/oxide/InGaP MOS Schottky diode is observed. Under the applied voltage of -1V and 50ppm H2/air, a high sensitivity of 1090 is obtained. In addition, an obvious variation of output current and a short response time due to the exposure to different H2 concentration are also achieved.

Improving the Performance of Hydrogen Sensors with Novel TiO2 Nanotube Arrays Hybrid Structure

2019 ◽  
Vol 803 ◽  
pp. 120-123
Author(s):  
Xiong Bang Wei ◽  
Guo Dong Lv ◽  
Xiao Hui Yang ◽  
Tao Wu ◽  
Dong Shi ◽  
...  
Keyword(s):  
Room Temperature ◽  
Research Work ◽  
High Sensitivity ◽  
Hydrogen Sensor ◽  
Hybrid Structure ◽  
Nanotube Arrays ◽  
Hybrid Nanostructure ◽  
Hydrogen Sensors ◽  
Novel Structure ◽  
Titanium Wire

In this paper, a kind of novel TiO2 nanotube arrays (TNTs) hybrid structure was presented to improve the performance of hydrogen sensors. In this novel structure, palladium functionalized TNTs hybrid nanostructure supported on titanium wire. TNTs arrays was prepared by anodizing Ti wire using a standard electrochemical procedure. Pd nanomaterials were deposited on TNTs. Optimized experiments showed the hydrogen sensor supported on titanium wire showed a good response time of 8 s and high sensitivity of 94.8% at 1.9 vol% H2 at room temperature (25 °C). The research work revealed potential good hydrogen sensitivity of this kind of hybrid nanostructure.

A Room Temperature Hydrogen Sensor With High Sensitivity and Selectivity Using Nanocrystalline Semiconductor Particles

2005 ◽  
Author(s):  
Peng Zhang ◽  
Satyajit Shukla ◽  
Larry Ludwig ◽  
Hyoung J. Cho ◽  
Sudipta Seal
Keyword(s):  
Room Temperature ◽  
High Sensitivity ◽  
Hydrogen Sensor ◽  
Interdigitated Electrodes ◽  
Semiconductor Particles ◽  
Sensitivity And Selectivity ◽  
Good Repeatability ◽  
Nanocrystalline Semiconductor

Micro hydrogen sensor with interdigitated electrodes and indium doped nanopolycrystalline SnO2 particles was fabricated and tested. Giant sensitivity as high as 105 with good repeatability and recovery was observed. The sensor showed an excellant selectivity of hydrogen (H2) sensing over helium (He).

scholarly journals A room-temperature ultrasonic hydrogen sensor based on a sensitive layer of reduced graphene oxide

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Xue-Yu Zhang ◽  
Ren-Hao Ma ◽  
Ling-Sheng Li ◽  
Li Fan ◽  
Yue-Tao Yang ◽  
...  
Keyword(s):  
Graphene Oxide ◽  
Frequency Shift ◽  
Reduced Graphene Oxide ◽  
Room Temperature ◽  
High Sensitivity ◽  
Hydrogen Sensor ◽  
Ultrasonic Sensor ◽  
Sensitive Layer ◽  
Reduced Graphene ◽  
Mass Load

AbstractIt is challenging to increase the sensitivity of a hydrogen sensor operating at room temperature due to weak sorption and tiny mass of hydrogen. In this work, an ultrasonic sensor is presented for detecting hydrogen, which is composed of a 128° YX-LiNbO3 substrate and a reduced graphene oxide (RGO) sensitive layer with a platinum catalyzer. By optimizing the depositing parameters of RGO and platinum, a considerably high sensitivity is achieved at room temperature. A frequency shift of 308.9 kHz is obtained in 100 ppm hydrogen mixed with argon, and a frequency shift of 24.4 kHz is obtained in 1000 ppm hydrogen mixed in synthetic air. It is demonstrated that in addition to strong sorption of the sensitive layer, the coaction of mass load and conductivity variation is key to high sensitivity of the sensor. By establishing the original conductivity of the sensitive layer within the “conductivity window” for enhancing electrical response, we improve the sensitivity of the ultrasonic sensor, which is available for detecting hydrogen with an extremely low concentration of 5 ppm.

THE STUDY ON TA VAT WINE PRODUCTION FROM SUGAR PALM (ARENGA PINNATA) SAP

2014 ◽  
Vol 83 (5) ◽  
Author(s):  
Nguyễn Thị Hồng Thu ◽  
Đặng Minh Nhật ◽  
Nguyễn Hoàng Dung
Keyword(s):  
Room Temperature ◽  
Fermentation Process ◽  
Inoculum Size ◽  
Wine Fermentation ◽  
Wine Production ◽  
Factors Affecting ◽  
Natural Fermentation ◽  
Tropical Asia ◽  
Best Parameters

Sugar palm (Arenga pinnata) is a feather palm native to tropical Asia. In Vietnam, it is named Búng Báng or Đoác and grown only on the highlands in the central or northern part of Vietnam. It is utilized for many purposes, especially for Ta Vat wine production - a characteristic and unique product of Co Tu ethnic minority. However, because of the natural fermentation used in the production, the product quality is inconsistent. The purpose of this study was to examine a new procedure of using palm sap for making Ta Vat wine. Some characteristics of the sap, which was collected at Nam Giang district, Quang Nam province are determined, proving the potential of the sap for making wine product. The quality of sap changes quickly at room temperature. At low temperature (4 - 60C), the changes in sap quality are apparently slower. Examining some factors affecting its quality during the wine fermentation process, we determined the best parameters for the fermentation process as follows: inoculum size of 3% with cell density of about 1x108 cells/ml, the addition of the extract from the bark of Ceylon ironwood (Mesua ferrea L.) 4%. Keywords: Arenga pinnata, sap, Ceylon ironwood bark, Mesua ferrea L., wine fermentation.

ASSECSSING MOCA TEST IN SUBACUTE STROKE PATIENTS AND COMPARE MOCA VERSUS MMSE

2016 ◽  
pp. 120-127
Author(s):  
Dinh Toan Nguyen
Keyword(s):  
Human Life ◽  
Statistical Significance ◽  
High Sensitivity ◽  
Stroke Patients ◽  
Cross Sectional ◽  
Female Age ◽  
Subacute Stroke ◽  
Duration Of Illness ◽  
Dsm Iv

Background: Dementia after stroke, particularly subacute period is often overlooked. Today the quality of human life is increasingly high, finding scales that have high value for detection of dementia in patients with stroke is increasingly interested. MoCA test is high sensitivity with mild dementia and identify more abnormalities of awareness caused by vascular, but MoCA have not been studied much in Vietnam. Objective: Assessing MoCA test in subacute stroke patients and compare MoCA versus MMSE in these patients. Subjects: 90 patients with subacute stroke period, these people are being treated at Department of cardiovascular internal medicine at Hue Central Hospital, from 7/2014 - 7/2015. Methods: cross-sectional description and analysis. Results: The mean age is 65.57 ± 13.38, accounting for 54.4% male and 45.6% female. Age, duration of illness has weak correlation with MoCA. The risk factors: hypertension, stroke ischemic transient, alcoholism, smoking, heart disease, diabetes, dyslipidemia related no statistical significance with MoCA. The proportion of dementia in subacute stroke according MoCA is 82.2%. The concordance between MoCA and MMSE was good (kappa = 0.684). Using DSM-IV criteria as the gold standard we found MoCA more valuable in the dementia diagnosis than MMSE (AUC 0.864 versus 0.774, p <0.05). Conclusion: The rate of dementia in stroke subacute period according MoCA is quite high. MoCA is valuable than MMSE in detecting dementia in patients with stroke subacute period, this scale is short, easy to implement so should put into using widely in clinical practice. Key words: MoCA test, subacute stroke, dementia

UV-assisted High-sensitivity Room-temperature Pd-gated HEMT NO2Gas Sensor

2021 ◽  
Author(s):  
Chong Xing ◽  
Dongcheng Xie ◽  
Haochen Zhang ◽  
Kang Song ◽  
Lei Yang ◽  
...  
Keyword(s):  
Room Temperature ◽  
High Sensitivity

scholarly journals In vitro characteristics and in vivo platelet quality of whole blood treated with riboflavin and UVA / UVB light and stored for 24 hours at room temperature

Transfusion ◽  
2021 ◽  
Vol 61 (S1) ◽  
Author(s):  
Turid Helen Felli Lunde ◽  
Lindsay Hartson ◽  
Shawn Lawrence Bailey ◽  
Tor Audun Hervig
Keyword(s):  
Whole Blood ◽  
Room Temperature

Proteinase and phospholipase activities and development at different temperatures of yeasts isolated from bovine milk

2011 ◽  
Vol 78 (4) ◽  
pp. 385-390 ◽  
Author(s):  
Priscilla A Melville ◽  
Nilson R Benites ◽  
Monica Ruz-Peres ◽  
Eugenio Yokoya
Keyword(s):  
Dairy Products ◽  
Room Temperature ◽  
Bovine Milk ◽  
Raw Milk ◽  
Pathogenic Potential ◽  
Proteinase Production ◽  
Different Temperatures ◽  
Quality Of Milk ◽  
Means Of Transmission

The presence of yeasts in milk may cause physical and chemical changes limiting the durability and compromising the quality of the product. Moreover, milk and dairy products contaminated by yeasts may be a potential means of transmission of these microorganisms to man and animals causing several kinds of infections. This study aimed to determine whether different species of yeasts isolated from bovine raw milk had the ability to develop at 37°C and/or under refrigeration temperature. Proteinase and phospholipase activities resulting from these yeasts were also monitored at different temperatures. Five genera of yeasts (Aureobasidium sp., Candida spp., Geotrichum spp., Trichosporon spp. and Rhodotorula spp.) isolated from bovine raw milk samples were evaluated. All strains showed one or a combination of characteristics: growth at 37°C (99·09% of the strains), psychrotrophic behaviour (50·9%), proteinase production (16·81% of the strains at 37°C and 4·09% under refrigeration) and phospholipase production (36·36% of the isolates at 37°C and 10·9% under refrigeration), and all these factors may compromise the quality of the product. Proteinase production was similar for strains incubated at 37°C (16·81% of the isolates) and room temperature (17·27%) but there was less amount of phospholipase-producing strains at room temperature (15·45% of the isolates were positive) when compared with incubation at 37°C (36·36%). Enzymes production at 37°C by yeasts isolated from milk confirmed their pathogenic potential. The refrigeration temperature was found to be most efficient to inhibit enzymes production and consequently ensure better quality of milk. The viability of yeasts and the activity of their enzymes at different temperatures are worrying because this can compromise the quality of dairy products at all stages of production and/or storage, and represent a risk to the consumer.

scholarly journals AB0050 A NOVEL METHOD FOR ISOLATION OF EXOSOMES FROM SYNOVIAL FLUID

2021 ◽  
Vol 80 (Suppl 1) ◽  
pp. 1057.2-1057
Author(s):  
Y. Liu ◽  
Y. Huang ◽  
Q. Huang ◽  
S. Sun ◽  
Z. Ji ◽  
...  
Keyword(s):  
Synovial Fluid ◽  
Western Blot ◽  
Biological Fluid ◽  
High Sensitivity ◽  
Protein Distribution ◽  
Sds Page ◽  
Close Relationship ◽  
Novel Method ◽  
Low Levels

Background:Exosomes in synovial fluid (SF) has a close relationship with the pathogenesis of rheumatiod arthritis. As a complex biological fluid, SF presents challenges for exosomes isolation using standard methods, such as ExoquickTM kit and ultracentrifugation.Objectives:The study aims to compared the quality of exosomes separated by ExoquickTM kit (TM), ExoquickTM kit+ExoquickTC kit (TM-TC), ultracentrifugation (UC) and TM-TC+UC(TM-TC-UC) from SF.Methods:Exosomes was separated by TM, TM-TC, UC and TM-TC-UC respectively. The size and concentrations of exosomes were detected by high sensitivity flow cytometry for nanoparticle analysis. Total protein and RNA were extracted from exosomes. SDS-PAGE was used to detect the protein distribution of exosomes. Western blot was used to examine the level of albumin and exosomes marker (TSG101 and CD81).Results:There was no statistic difference in the diameters of exosomes separated by the four methods. The concentrations of exosomes in TM, TM-TC, TM-TC-UC and UC were (5.65±0.93), (3.02±1.19), (1.67±0.25) and (4.61±0.73) *109Particles/mL. The protein concentrations of exosomes separated by the four methods were consistent with the concentrations of exosomes. SDS-PAGE showed that the protein distribution of exosomes separated by the four methods were different. Low levels of albumin were detected in TM-TC and TM-TC-UC, while high levels of albumin in TM and UC. Total RNA concentrations from exosomes in TM-TC was higher than other groups.Conclusion:TM-TC can be used to obtain higher quality exosomes from SF for the study of exosome-enriched components.References:[1]Helwa I, et al, A Comparative Study of Serum Exosome Isolation Using Differential Ultracentrifugation and Three Commercial Reagents. PloS one, 2017. 12(1): p. e0170628-e0170628.Figure 1.A: SDS-PAGE showed the protein distribution of exosomes; B: the detection of albumin, TSG101 and CD81 by western blot.Disclosure of Interests:None declared

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