Patterned Deposition from Compressed Carbon Dioxide

2002 ◽  
Vol 734 ◽  
Author(s):  
C. K. Luscombe ◽  
W. T. S. Huck ◽  
A. B. Holmes ◽  
T. Lu ◽  
G. A. Leeke ◽  
...  

ABSTRACTCompressed CO2 is employed as the solvent for the deposition of polymers onto patterned surfaces created by a lithographic technique. This deposition technique should have wide applicability in the deposition of organic and polymeric materials for optoelectronic devices. The advantage of controlled deposition confers a further benefit in the control of the patterned surface. In a specific example a perfluorinated polymer was dissolved in liquid carbon dioxide. The polymer solution was deposited by use of a nozzle onto a pre-patterned surface. The resulting polymer film showed a clear image of the original pattern as measured by optical microscopy.

2021 ◽  
Vol 287 ◽  
pp. 106106
Author(s):  
Xianfeng Liu ◽  
Baisheng Nie ◽  
Kunyong Guo ◽  
Chengpeng Zhang ◽  
Zepeng Wang ◽  
...  

Physica ◽  
1973 ◽  
Vol 63 (1) ◽  
pp. 154-162 ◽  
Author(s):  
W. Pecceu ◽  
W. Van Dael

2006 ◽  
Vol 7 (8) ◽  
pp. n/a-n/a ◽  
Author(s):  
John Lupton ◽  
David Butterfield ◽  
Marvin Lilley ◽  
Leigh Evans ◽  
Ko-ichi Nakamura ◽  
...  

2013 ◽  
Vol 634-638 ◽  
pp. 3688-3695 ◽  
Author(s):  
Yang Xiao ◽  
Shu Gang Li ◽  
Jun Deng ◽  
Xu Wang

In China, as popularizing the technology of fully mechanized top-coal mining and increasing the strength and depth of mining, the gutter-up gob can be formed. But the work of fire preventing and extinguishing for its coal spontaneous combustion is more complexity and difficulty. In this paper, based on geology parameters and mining practice for 93up12 fully mechanized top-coal caving face in Nantun coalmine, the form and character of gutter-up gob are analyzed. According to the hidden danger of high temperature for spontaneous combustion in the gob, we adopt the comprehension technologies of fire extinguishing and preventing which include sealing air-leakage, grouting, and injecting compound gel with fly-ash, foam of retarding oxidation, liquid carbon dioxide, and gas of nitrogen. By putting in practice the pre-controlling technology in gutter-up gob and monitoring data of target gases, it obtains a good effect and ensures the safety in production of the fully-mechanized top-coal caving face.


2012 ◽  
Vol 67 (10) ◽  
pp. 961-975 ◽  
Author(s):  
Markus Hölscher ◽  
Christoph Gürtler ◽  
Wilhelm Keim ◽  
Thomas E. Müller ◽  
Martina Peters ◽  
...  

With the growing perception of industrialized societies that fossil raw materials are limited resources, academic chemical research and chemical industry have started to introduce novel catalytic technologies which aim at the development of economically competitive processes relying much more strongly on the use of alternative carbon feedstocks. Great interest is given world-wide to carbon dioxide (CO2) as it is part of the global carbon cycle, nontoxic, easily available in sufficient quantities anywhere in the industrialized world, and can be managed technically with ease, and at low cost. In principle carbon dioxide can be used to generate a large variety of synthetic products ranging from bulk chemicals like methanol and formic acid, through polymeric materials, to fine chemicals like aromatic acids useful in the pharmaceutical industry. Owing to the high thermodynamic stability of CO2, the energy constraints of chemical reactions have to be carefully analyzed to select promising processes. Furthermore, the high kinetic barriers for incorporation of CO2 into C-H or C-C bond forming reactions require that any novel transformation of CO2 must inevitably be associated with a novel catalytic technology. This short review comprises a selection of the most recent academic and industrial research developments mainly with regard to innovations in CO2 chemistry in the field of homogeneous catalysis and processes.


2006 ◽  
Vol 45 (10) ◽  
pp. 3434-3437 ◽  
Author(s):  
Ha Soo Hwang ◽  
Min Young Lee ◽  
Yeon Tae Jeong ◽  
Seong-Soo Hong ◽  
Yeong-Soon Gal ◽  
...  

2017 ◽  
Vol 44 (12) ◽  
pp. 19-22
Author(s):  
A.S. Shabaev ◽  
S.Yu. Khashirova ◽  
A.K. Mikitaev ◽  
I.V. Musov ◽  
A.L. Slonov

The diffusion cell to a Tsvet-800 chromatograph for determining the gas permeability of polymeric materials has been optimised. The oxygen permeability and the carbon dioxide permeability of polymer composites based on polyethylene terephthalate and polybutylene terephthalate have been studied. The optimum compositions, combining high barrier properties and a low acetaldehyde content, have been found.


2014 ◽  
Vol 3 (4) ◽  
pp. 119 ◽  
Author(s):  
Raffaele Romano ◽  
Nadia Manzo ◽  
Immacolata Montefusco ◽  
Annalisa Romano ◽  
Antonello Santini

<p>In this study the use of liquid carbon dioxide, CO<sub>2</sub>, for extraction of oil from olive paste (<em>Peranzana cultivar</em>)<strong> </strong>were examined and extracted oil was compared with oils obtained by centrifugation, pressure and use of chemical solvent.</p> <p>It is well known that the use of CO<sub>2</sub> has many advantages: miscibility with a wide range of molecules, food safety, non-flammability, absence of residues in the extract, possibility of total solvent recovery and no production of olive mill waste water that are highly polluting for the environment and require expansive disposal.</p> <p>Samples were subjected to the following analyses: determination of Free Fatty Acids (FFA), Peroxides Value (PV), Spectrophotometric Indices, Fatty Acids Composition (FA), determination of biophenols content and determination of Volatile Organic Compounds (VOCs). All samples showed FFA, PV and ?K values within the limits established by law for extra-virgin olive oil. The use of CO<sub>2</sub> did not catalyze hydrolysis, oxidation and condensation of double bonds. Centrifuged oils and oils extracted with carbon dioxide presented the lowest PV and FFA values. Extraction with liquid carbon dioxide contributed to an increasing of phenolic content with a value of 270.5 mg/kg, a value twice that of the oils extracted with centrifugation (135.3 mg/kg) or pressure methods (173.2 mg/kg). Oil extracted with liquid carbon dioxide showed the greatest amount of t-2-octenal and t-2-heptenal, giving herbaceous and pungent notes. Moreover the presence of aromatic compounds such as limonene, generally absent in olive oils, was only detected in the sample extracted with liquid carbon dioxide.</p>


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