Development of low temperature curing, 120°C, durable, corrosion protection powder coatings for temperature sensitive substrates

Blends of chloroprene rubber (CR) and bromobutyl rubber (BIIR) are used in making the undersea sensors watertight by a process of encapsulation. The encapsulation process is conventionally done at high temperature approximately 150°C and above using high-temperature vulcanization (HTV). However, the new class of acoustic sensors like polyvinilidenefluride (PVDF) and thin film PZT are highly temperature sensitive and fragile in nature and hence they require low-temperature vulcanization (LTV) process to avoid damages and protect their full functionalities. However, conventional cure systems are not adoptable in LTV process and hence there is a need for the search of alternate cure systems. Not much work has been reported in this area. This article reports a nonconventional cure system vulcanizable with LTV and the associated reaction kinetics for a commonly used CR–BIIR blend for encapsulation of undersea sensors. Formulations have been attempted with cure systems based on red lead (Pb3O4) and zinc oxide (ZnO) for CR–BIIR blend in 80:20 weight ratio, instead of zinc oxide, magnesium oxide, and ethylene thiourea system, which are conventionally used in HTV. The cure parameters at low temperature between 70°C and 120°C and the activation energy for cure reactions ( E a) were estimated using MDR 2000 rheometer. Essential prerequisites like water resistance, electrical resistivity, and physicomechanical properties for sensor application are qualitatively analyzed for the blend cured at 90°C. The results reveal that the proposed nonconventional cure systems are able to bring down the cure temperature of CR–BIIR blend to 90°C from 150°C enabling the suitability of the materials for undersea sensor encapsulation.

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Low Temperature Synthesis of Lithium-Doped Nanocrystalline Diamond Films with Enhanced Field Electron Emission Properties

Nanomaterials ◽

10.3390/nano8090653 ◽

2018 ◽

Vol 8 (9) ◽

pp. 653 ◽

Cited By ~ 2

Author(s):

Kamatchi Sankaran ◽

Kalpataru Panda ◽

Ping-Yen Hsieh ◽

Paulius Pobedinskas ◽

Jeong Park ◽

...

Keyword(s):

Low Temperature ◽

Electron Emission ◽

High Current Density ◽

Field Enhancement ◽

Life Time ◽

Field Electron Emission ◽

Nanocrystalline Diamond ◽

Large Field ◽

Temperature Sensitive ◽

Field Electron

Low temperature (350 °C) grown conductive nanocrystalline diamond (NCD) films were realized by lithium diffusion from Cr-coated lithium niobate substrates (Cr/LNO). The NCD/Cr/LNO films showed a low resistivity of 0.01 Ω·cm and excellent field electron emission characteristics, viz. a low turn-on field of 2.3 V/µm, a high-current density of 11.0 mA/cm2 (at 4.9 V/m), a large field enhancement factor of 1670, and a life-time stability of 445 min (at 3.0 mA/cm2). The low temperature deposition process combined with the excellent electrical characteristics offers a new prospective for applications based on temperature sensitive materials.

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Regional Temperature-Sensitive Diseases and Attributable Fractions in China

International Journal of Environmental Research and Public Health ◽

10.3390/ijerph17010184 ◽

2019 ◽

Vol 17 (1) ◽

pp. 184

Author(s):

Xuemei Su ◽

Yibin Cheng ◽

Yu Wang ◽

Yue Liu ◽

Na Li ◽

...

Keyword(s):

Low Temperature ◽

Extreme Temperature ◽

Attributable Fraction ◽

Mortality Data ◽

Temperature Sensitive ◽

Subtropical Climate ◽

Climate Zones ◽

Attributable Fractions ◽

Regional Temperature ◽

Study Sites

Few studies have been carried out to systematically screen regional temperature-sensitive diseases. This study was aimed at systematically and comprehensively screening both high- and low-temperature-sensitive diseases by using mortality data from 17 study sites in China located in temperate and subtropical climate zones. The distributed lag nonlinear model (DLNM) was applied to quantify the association between extreme temperature and mortality to screen temperature-sensitive diseases from 18 kinds of diseases of eight disease systems. The attributable fractions (AFs) of sensitive diseases were calculated to assess the mortality burden attributable to high and low temperatures. A total of 1,380,713 records of all-cause deaths were involved. The results indicate that injuries, nervous, circulatory and respiratory diseases are sensitive to heat, with the attributable fraction accounting for 6.5%, 4.2%, 3.9% and 1.85%, respectively. Respiratory and circulatory diseases are sensitive to cold temperature, with the attributable fraction accounting for 13.3% and 11.8%, respectively. Most of the high- and low-temperature-sensitive diseases seem to have higher relative risk in study sites located in subtropical zones than in temperate zones. However, the attributable fractions for mortality of heat-related injuries were higher in temperate zones. The results of this research provide epidemiological evidence of the relative burden of mortality across two climate zones in China.

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The Deposition of Silicon Oxide Films by LPCVD at Temperatures as Low as 100°C from a New Liquid Source

MRS Proceedings ◽

10.1557/proc-282-569 ◽

1992 ◽

Vol 282 ◽

Cited By ~ 1

Author(s):

K. Hochberg ◽

David A. Roberts

Keyword(s):

Low Temperature ◽

Silicon Oxide ◽

Oxide Films ◽

Temperature Sensitive ◽

Oxide Layers ◽

Low Temperature Deposition ◽

Liquid Source ◽

Temperature Deposition ◽

Higher Temperature

ABSTRACTA precursor for the LPCVD of silicon oxide films has been developed that extends the low temperature deposition range to 100°C. The chemical, 1,4 disilabutane (DSB), produces silicon oxide depositions similar to those of the higher temperature silane and diethylsilane (DES) processes. Optimum DSB processes require pressures below 300 mTorr, similar to silane, in contrast to DES pressures above 600 mTorr at 350°C. This results in poorer conformalities than those of DES, but the step coverages are still superior to those from silane oxides. The DSB films are low stress, carbon-free oxide layers that are suitable for temperature-sensitive underlayers and substrates such as photoresist, plastics, GaAs, and HgCdTe.

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Characterization and genetic analysis of a low-temperature-sensitive mutant, sy-2, in Capsicum chinense

Theoretical and Applied Genetics ◽

10.1007/s00122-010-1460-0 ◽

2010 ◽

Vol 122 (3) ◽

pp. 459-470 ◽

Cited By ~ 7

Author(s):

Song-Ji An ◽

Devendra Pandeya ◽

Soung-Woo Park ◽

Jinjie Li ◽

Jin-Kyung Kwon ◽

...

Keyword(s):

Low Temperature ◽

Genetic Analysis ◽

Temperature Sensitive ◽

Capsicum Chinense ◽

Sensitive Mutant ◽

Temperature Sensitive Mutant

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Synthesis, Structural and Gas Sensing Characterization of W-Doped SnO2 Nanostructures

Defect and Diffusion Forum ◽

10.4028/www.scientific.net/ddf.381.15 ◽

2017 ◽

Vol 381 ◽

pp. 15-19 ◽

Cited By ~ 1

Author(s):

Mukesh Chander Bhatnagar ◽

Anima Johari

Keyword(s):

Low Temperature ◽

Gas Sensors ◽

Gas Sensing ◽

Operating Temperature ◽

Environmental Pollutants ◽

Sensor Response ◽

Gas Content ◽

Temperature Sensitive ◽

Oxide Material ◽

Industry Waste

Tin oxide material has been extensively used for gas sensing application. Due to high operating temperature of metal oxide gas sensors, around 600 K and long term instability, research has been carried out to improve the material properties and reducing operating temperature. nanostructure materials have shown higher sensitivity and better stability towards gas environment. Air pollutants from automobiles and industry waste are the primary sources of environmental pollutants and there is need to develop low temperature, sensitive and selective gas sensors to monitor the gas content. In this paper, we have discussed the effect of Tungsten (W) doping in SnO2 nanostructures on the structural and gas sensing properties. The nanostructures have been synthesized by thermal evaporation process. The structural and surface morphology studies confirm the growth of nanowires on silicon substrates. The corresponding EDX spectra also confirm the doping of W into SnO2 nanowires. The gas sensor response of W-doped SnO2 nanowires was investigated upon exposure to various gases. It has been observed that doping of W enhances the NO2 sensitivity of nanowire based sensors at low temperature and the sensor response improves with increase in gas concentration.

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