Phase state diagram of a poly(amic acid)–solvent–nonsolvent system

2018 ◽  
Vol 67 (10) ◽  
pp. 1831-1837 ◽  
Author(s):  
A. A. Shcherbina ◽  
V. K. Gerasimov ◽  
T. P. Semenov ◽  
A. E. Chalykh
Keyword(s):  
2017 ◽  
Vol 19 (9) ◽  
pp. 6532-6545 ◽  
Author(s):  
Nicholas E. Rothfuss ◽  
Markus D. Petters

The amorphous phase state diagram for sucrose aerosol is obtained from a mix of measurements and model calculations.


2020 ◽  
Vol 303 ◽  
pp. 97-103
Author(s):  
V.A. Vlasov ◽  
Anatoliy A. Klopotov ◽  
V.I. Vereshchagin ◽  
O.G. Volokitin ◽  
K.A. Bezukhov ◽  
...  

The paper presents the results of the analysis of the state diagram of compounds in the system А12O3-SiO2. It has been found that the presence and the concentration of oxygen have a very important effect on formation of compounds with a crystalline structure in different syngony based on SIALON. Oxygen contributes to transition of the metastable AlXSi3-XN4compound into stable one. The parameter of structural “friability” of compounds has been used in the analysis of thethermodynamic stability of compounds in the Al-Si-N-O system. It has been foundthat the SiAl4O2N4 compound with the 12H-SIALON structure (Pearson symbol hP32) has the greatest thermodynamic stability among the compounds under study in this system.


1989 ◽  
Vol 57 (4) ◽  
pp. 1184-1190
Author(s):  
I. I. Novikov ◽  
I. P. Vishnev ◽  
A. I. Vishnev
Keyword(s):  

Fibers ◽  
2021 ◽  
Vol 9 (5) ◽  
pp. 28
Author(s):  
Tatiana V. Plisko ◽  
Alexandr V. Bildyukevich ◽  
Liang Zhao ◽  
Weiqing Huang ◽  
Vladimir V. Volkov ◽  
...  

This study deals with the investigation of the phase state of the polymer systems from polysulfone (PSF) with the addition of polyethylene glycol (PEG-400, Mn = 400 g·mol−1) and polyvinylpyrrolidone (PVP K-30, Mn = 40,000 g·mol−1) in N,N-dimethylacetamide (DMA), which feature lower critical solution temperatures (LCSTs). A fragment of the phase state diagram of the system PSF —PEG-400—PVP K-30—DMA was experimentally constructed in the following range of component concentrations: PSF 20–24 wt.%, PEG-400—35–38 wt.% and PVP—0–8 wt.%. It has been established that PVP addition substantially reduces the phase separation temperature down to 50–60 °C. Based on the obtained phase diagrams, a method for preparation of highly permeable hollow fiber membranes from PSF, which involves the processing of the dope solution at a temperature close to the LCST and the temperature of the bore fluid above the LCST, was proposed. Hollow fiber membranes with pure water flux of 1200 L·m−2·h−1 and a sponge-like macrovoid-free structure were obtained via LCST-thermally induced phase separation by free fall spinning technique.


2008 ◽  
Vol 128 (7) ◽  
pp. 1185-1190 ◽  
Author(s):  
Kuniaki Fujimoto ◽  
Hirofumi Sasaki ◽  
Mitsutoshi Yahara
Keyword(s):  

2019 ◽  
Author(s):  
Matthieu Riva ◽  
Yuzhi Chen ◽  
Zhang, Yue ◽  
Ziying Lei ◽  
Nicole Olson ◽  
...  

<div>Acid-driven multiphase chemistry of isoprene epoxydiols (IEPOX), a key isoprene oxidation product, with inorganic sulfate aerosol yields substantial amounts of secondary organic aerosol (SOA) through the formation of organosulfur. The extent and implications of inorganic-to-organic sulfate conversion, however, are unknown. Herein, we reveal that extensive consumption of inorganic sulfate occurs, which increases with the IEPOX-to-inorganic sulfate ratio (IEPOX:Sulf<sub>inorg</sub>), as determined by laboratory and field measurements. We further demonstrate that organosulfur greatly modifies critical aerosol properties, such as acidity, morphology, viscosity, and phase state. These new mechanistic insights reveal that changes in SO<sub>2</sub> emissions, especially in isoprene-dominated environments, will significantly alter biogenic SOA physicochemical properties. Consequently, IEPOX:Sulf<sub>inorg</sub> will play a central role in understanding historical climate and determining future impacts of biogenic SOA on global climate and air quality.</div>


2018 ◽  
Author(s):  
Ibukun Makinde

Gas condensates are liquid mixtures of high-boiling hydrocarbons of various structures, separated from natural gases during their production at gas condensate fields. When transporting gas through pipelines, the following gas quality conditions should be met:i.During transportation, gases should not cause corrosion of pipelines, fittings, instruments, etc.ii.The quality of the gas must ensure its transportation in a single-phase state i.e., liquid hydrocarbons, gas condensates and hydrates should not form in the pipelines.In order for gas condensates to meet the above-mentioned quality conditions during storage or transportation, they must be stabilized. Gas condensate stabilization is the process of “boiling off” light hydrocarbons from the condensate that would otherwise increase the vapor pressure when conditions are fluctuating.


1995 ◽  
Vol 60 (10) ◽  
pp. 1741-1746
Author(s):  
Jan Schauer ◽  
Miroslav Marek

Poly(amic acid) prepared from 3,3',4,4'-benzophenonetetracarboxylic dianhydride and bis(4-aminophenyl) ether was used for preparation of microporous membranes by the phase inversion process. Membranes coagulated in acetic anhydride were brittle but usable for ultrafiltration. Coagulation of the poly(amic acid) in water or lower alcohols and subsequent thermal cyclocondensation led to extremely brittle polyimides, which limits their use for ultrafiltration process.


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