Polymer time constants during low temperature nanoimprint lithography

It is very hard to fabricate nano-strctures on PEDOT:PSS film by conventional Nanoimprint Lithography for its non-thermoplastic property. Here we demonstrated a new nanoimprint process to pattern the PEDOT:PSS film at low temperature and low pressure by adding proper amount of Glycerol into PEDOT:PSS solution and pressing the Si-mold into Glycerol-PEDOT:PSS film under a pressure of 6.2Mpa for 45min at 80°C. We also compared our result to L. Tan and co-workers’. They found that positive replica was left on PEDOT:PSS film after pressing the Si-mold into Glycerol-PEDOT:PSS film under a pressure of 10Kpa for 5min at 80°C, but our work showed negative replica formed. Pressing time maybe is the critical reason to explain the different results. Holding the pressure longer gave the PEDOT:PSS enough time to flow into Si-mold and also gave Glycerol enough time to evaporate so that PEDOT:PSS became strong enough when separated the Si-mold from the PEDOT:PSS film. At last, Roman spectra was measured to confirm adding glycerol to PEDOT:PSS will not influence its molecular structure.

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Growth of Defect-Induced Carbon Nanotubes for Low-Temperature Fruit Monitoring Sensor

Chemosensors ◽

10.3390/chemosensors9060131 ◽

2021 ◽

Vol 9 (6) ◽

pp. 131

Author(s):

Nagih M. Shaalan ◽

Osama Saber ◽

Faheem Ahmed ◽

Abdullah Aljaafari ◽

Shalendra Kumar

Keyword(s):

Carbon Nanotubes ◽

Low Temperature ◽

Recovery Time ◽

Smooth Surface ◽

Operating Temperature ◽

Sensor Response ◽

Time Constants ◽

Gas Concentration ◽

Low Intensity ◽

Response And Recovery

Herein, a carbon nanotubes-based sensor has been grown for the purpose of ethylene detection. The prepared CNTs had a crystalline structure with a smooth surface of 11.0 nm in diameter and 10.0 µm in length. The low-intensity graphite peak (G-band) as compared to the peak of the defect (D-band) characterizes the defects in the CNTs. An MWNTs-gas sensor was fabricated for monitoring the ethylene gas. The highest response was recorded at a low operating temperature of 30 °C. The sensor was also examined at 300 ppb up to 10 ppm and it showed a response of 2% up to 28%. The sensor response and recovery time constants were varied from 60 to 300 s, depending on the gas concentration. The results that were obtained for the synthetic ethylene gas were also compared with the real measurements for banana ripening. The results confirmed that the sensor is appropriate for the monitoring of fruit ripening.

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Dye Transport Across the Retinal Basement Membrane of the Blowfly Calljphora Erythrocephala

Journal of Experimental Biology ◽

10.1242/jeb.141.1.47 ◽

1989 ◽

Vol 141 (1) ◽

pp. 47-59

Author(s):

E. WEYRAUTHER ◽

J. G.H. ROEBROEK ◽

D. G. STAVENGA

Keyword(s):

Low Temperature ◽

Transport Process ◽

Trypan Blue ◽

Lucifer Yellow ◽

Phenol Red ◽

Calliphora Erythrocephala ◽

Time Constants ◽

Dye Transport ◽

Procion Yellow ◽

Active Processes

In the blowfly, Calliphora erythrocephala, transport of dye into or out of the retina, following injection into the eye or thorax, was investigated, mainly by microspectrophotometry and fluorimetry. After injection into the eye, Phenol Red, Trypan Blue, Lucifer Yellow and 9-amino-acridine were transported out of the retina; Procion Yellow and Rhodamine-123 stayed in it. The time constants of this transport process were in the range 45–80 min at 23°C, depending on the dye. When Lucifer Yellow was injected into the thorax, it was transported into the retina. The transport of these dyes across the retina was inhibited by nitrogen, ouabain and low temperature, indicating that active processes are involved.

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