Minimum temperature difference detected by the thermal radiation of objects

In this paper, two kinds of suspended micro hotplate with novel shapes of multibeam structure and reticular structure are designed. These designs have a reliable mechanical strength, so they can be designed and fabricated on single-layer SiO2 suspended film through a simplified process. Single-layer suspended film helps to reduce power consumption. Based on the new film shapes, different resistance heaters with various widths and thicknesses are designed. Then, the temperature uniformity and power consumption of different micro hotplates are compared to study the effect of these variables and obtain the one with the optimal thermal performance. We report the simulations of temperature uniformity and give the corresponding infrared images in measurement. The experimental temperature differences are larger than those of the simulation. Experimental results show that the lowest power consumption and the minimum temperature difference are 43 mW and 50 °C, respectively, when the highest temperature on the suspended platform (240 × 240 μm2) is 450 °C. Compared to the traditional four-beam micro hotplate, temperature non-uniformity is reduced by about 30–50%.

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Minimum temperature difference perceived—a new approach to assess undersampled thermal imagers

Optical Engineering ◽

10.1117/1.602265 ◽

1999 ◽

Vol 38 (5) ◽

pp. 773 ◽

Cited By ~ 19

Author(s):

Wolfgang Wittenstein

Keyword(s):

Temperature Difference ◽

Minimum Temperature ◽

New Approach ◽

Thermal Imagers

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Observations of Large-Scale Anisotropy in the 3 K Background Radiation

Symposium - International Astronomical Union ◽

10.1017/s007418090000601x ◽

1972 ◽

Vol 44 ◽

pp. 518-519 ◽

Cited By ~ 2

Author(s):

E. K. Conklin

Keyword(s):

Thermal Radiation ◽

Temperature Difference ◽

Large Scale ◽

Background Radiation ◽

Angular Size ◽

Systematic Effects ◽

Right Ascension

Measurements of the background radiation were made at 8000 MHz with a beamwidth of 15 deg. Two antennas were used, arranged such that the equipment recorded the temperature difference between points five hours apart in right ascension and at declination + 32°. Data were taken only at night and at 3800 m altitude, in order to reduce systematic effects as much as possible. Two observing runs six months apart were combined; after subtracting Galactic non-thermal radiation, the remainder shows a significant dipole anisotropy, a possibly significant quadrupole anisotropy, and no detectable variations of smaller angular size: (Table I.)

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Effects of day-night temperature combinations under constant day length on emergence and early growth of sericea lespedeza genotypes

Canadian Journal of Plant Science ◽

10.4141/p05-208 ◽

2007 ◽

Vol 87 (1) ◽

pp. 77-81

Author(s):

K. L. Kalburtji ◽

J. A. Mosjidis ◽

A. P. Mamolos

Keyword(s):

Temperature Difference ◽

Minimum Temperature ◽

Seedling Emergence ◽

Dry Weight ◽

Day Length ◽

Night Temperature ◽

Sericea Lespedeza ◽

Leaf Dry Weight ◽

Maximum Minimum ◽

Number Of Branches

Establishment of sericea lespedeza [Lespedeza cuneata (Dumont de Courset) G. Don.] in southeastern USA is difficult. Seedling emergence may be related to the range of temperatures prevalent during establishment. A growth chamber study was undertaken to measure the effect of temperature on seedling emergence of 56 sericea lespedeza genotypes. Main treatments were: (1) plants grown at three day-night temperature combinations with maximum/minimum temperature difference of 14°C. The temperature combinations were 22/8°C, 27/13°C, and 32/18°C; (2) plants grown at three day-night temperature combinations with maximum/minimum temperature difference of 7°C. This was accomplished by lowering the day temperature and keeping the night temperature the same as above. Emergence was reduced by about 27% with reduction of 7°C in day-night temperature within the range of temperatures used. Plant height, leaf dry weight, stem dry weight and number of branches were very sensitive to temperature combinations. Increases in temperature caused increases in height, leaf dry weight, stem dry weight and number of branches of all genotypes. Further screening of sericea for emergence and growth under low temperature may lead to cultivars with more vigorous seedlings that can be better established early in the season. Key words: Plant growth, temperatures, seedling emergence, Sericea, southern USA

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Numerical Simulation of Temperature Field in the Cyclone

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.614-615.208 ◽

2012 ◽

Vol 614-615 ◽

pp. 208-211

Author(s):

Zhen Wei Zhang ◽

Ying Yu ◽

Jie Leng ◽

Su Juan Zhang

Keyword(s):

Numerical Simulation ◽

Temperature Field ◽

Temperature Distribution ◽

Turbulence Model ◽

Temperature Difference ◽

Minimum Temperature ◽

Maximum Temperature ◽

Inlet Tube ◽

Higher Temperature ◽

Air Compression

The temperature distribution of the cyclone was analyzed in the presented work, which was imitated by using RSM turbulence model of software FLUENT. Temperature difference in different regions is less than one centigrade degree with the maximum temperature in the cone part and the minimum temperature in inlet tube and cylinder part of the cyclone, what’s more, the temperature is relatively higher near the wall. The air compression can lead the higher temperature in the lower part, so the cone part has the maximum temperature. The higher temperature near the wall is caused by the friction between the wall and flow.

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