Production of High-Concentration Graphene Dispersions in Low-Boiling-Point Organic Solvents by Liquid-Phase Noncovalent Exfoliation of Graphite with a Hyperbranched Polyethylene and Formation of Graphene/Ethylene Copolymer Composites

2013 ◽  
Vol 117 (20) ◽  
pp. 10730-10742 ◽  
Author(s):  
Lixin Xu ◽  
John-Wesley McGraw ◽  
Fan Gao ◽  
Mark Grundy ◽  
Zhibin Ye ◽  
...  
Keyword(s):  
Liquid Phase ◽  
Organic Solvents ◽  
Boiling Point ◽  
High Concentration ◽  
Ethylene Copolymer ◽  
Copolymer Composites

Competitive adsorption of organic solvents using modified and unmodified calcium bentonite clay mineral

2019 ◽  
Author(s):  
Chem Int
Keyword(s):  
Adsorption Isotherm ◽  
Adsorption Capacity ◽  
Organic Solvents ◽  
Competitive Adsorption ◽  
Correlation Factor ◽  
Isotherm Model ◽  
Isotherm Models ◽  
High Concentration ◽  
Dual Purpose ◽  
Calcium Bentonite

Dodecyltrimethylammonium bromide (DTAB)–modified and unmodified calcium bentonite were both used for the competitive adsorption of aromatics (xylene, ethylbenzene and toluene) and petroleum products (gasoline, dual purpose kerosene and diesel) from their aqueous solution. Infrared spectroscopy (IR) and expansion tests (adsorption capacity and Foster swelling) measurement were performed in order to evaluate the performance of the adsorbents. The Foster swelling index and adsorption capacity of the DTAB modified calcium bentonite in the organic solvents follow the trend: xylene > ethylbenzene > toluene > gasoline > dual purpose kerosene (DPK) > diesel > water. However, the adsorption capacity of the adsorbent in diesel outweighed the adsorption capacity in DPK at high concentration of DTAB indicating that diesel has higher affinity for high DTAB concentration than DPK. The percentage removal of the solvent is directly proportional to the concentration of DTAB used in modifying the bentonite as well as the contact time between the adsorbent and the solvent, hence modified calcium bentonite adsorbed a higher percentage of organic solvents than the unmodified calcium bentonite. The adsorption characteristics of both adsorbents improved remarkably after proper agitation of the organic solvents, the unmodified calcium bentonite however adsorbed more water than the modified bentonite. Data obtained from adsorption isotherm models confirms that Freundlich adsorption isotherm model was favored more than Langmuir adsorption isotherm model with the correlation factor (R2) of the former tending more towards unity. The adsorption of ethylbenzene using DTAB modified and unmodified calcium bentonites follow a pseudo second order kinetics mechanism, suggesting that the rate determining step of adsorption involves both the adsorbent and the organic solvent.

Diffusion In Insect Wing Muscle, The Most Active Tissue Known

1964 ◽  
Vol 41 (2) ◽  
pp. 229-256 ◽  
Author(s):  
TORKEL WEIS-FOGH
Keyword(s):  
Liquid Phase ◽  
Safety Factor ◽  
Metabolic Rates ◽  
High Concentration ◽  
Tracheal System ◽  
Insect Wing ◽  
Main Site ◽  
Normal Diffusion ◽  
Large Fibre ◽  
Very High

1. The tracheal system of insect wing muscle is so dense that between 10-1 and 10-3 of any cut area is occupied by air tubes. In most cases, air tube diffusion of O2 and CO2 through the muscle is therefore several thousand times quicker than diffusion in the liquid phase. 2. In large insects the primary tracheal supply must be strongly ventilated while diffusion is sufficient in the remaining part of the air tubes, even at the highest metabolic rates encountered in any insect. 3. The tracheoles represent the main site of exchange between the gaseous and the liquid phase while the tracheae are of little significance in this respect. The fibres cannot exceed about 20 µ in diameter unless the tracheoles indent the surface and become ‘internal’. 4. Muscular pumping of air and blood due to shortening is of little importance for the exchange of gases but of major importance for the supply with fuel for combustion. However, the large fibre diameters and the tidal nature of the pumping necessitates a very high concentration of fuel in the haemolymph. The high concentration of trehalose in insect blood is considered to be an essential adaptation to flapping flight. 5. The transport by diffusion of O2 and CO2 was followed in detail in a number of concrete examples in the gaseous as well as in the liquid phase. Within a safety factor of 2-3, the rate of transport was always found to be adequate. There is no reason to suggest other mechanisms than a simple, normal diffusion.

Effects of Amines on Chemical and Physical Behaviors of Viscous Precursor Sols to Indium Gallium Zinc Oxide

2013 ◽  
Vol 1547 ◽  
pp. 123-128 ◽  
Author(s):  
Nobuko Fukuda ◽  
Shintaro Ogura ◽  
Ken-ichi Nomura ◽  
Hirobumi Ushijima
Keyword(s):  
Zinc Oxide ◽  
Shear Rate ◽  
Metal Oxides ◽  
Boiling Point ◽  
Indium Gallium Zinc Oxide ◽  
High Concentration ◽  
Lower Shear ◽  
Metal Nitrates ◽  
Lower Shear Rate ◽  
Indium Gallium

ABSTRACTWe synthesized viscous precursors to indium gallium zinc oxide (IGZO) using three kinds of alcoholamines, ethanolamine (EA), diethanolamine (DEA), and triethanolamine (TEA), by a simple process. The viscous precursors are obtained just by vigorous stirring of alcoholamine and urea in an aqueous solution containing the metal nitrates during heating at 150-160 °C. The precursor containing EA (EA-precursor) is a pale-orange suspension containing aggregates of the metal hydroxides and shows pseudoplastic flow. The precursors containing DEA (DEA-precursor) and TEA (TEA-precursor) are transparent pale-yellow and dark-orange sols, respectively. They give Newtonian flow in the lower shear rate and pseudoplastic flow in the higher shear rate. Higher concentration of metal salts leads to higher viscosity of the precursors. According to thermogravimetry-differential thermal analysis (TG-DTA) for the EA- and DEA-precursors, evaporation of alcoholamine occurs at around each boiling point and subsequently formation of metal oxides occur at around 300 °C. In the case of the TEA-precursor, formation of metal oxides occurs before pyrolysis of TEA attributed to the higher boiling point of TEA. The thin IGZO film, which is prepared by spin-coating of the diluted DEA-precursor and subsequent sintering at 450 °C for 30 min, shows 0.02 cm2 ·V-1s-1 of the mobility and 10-5 of the on/off ratio. The highly viscous DEA-precursor containing high concentration of metal ions allows patterning in an area of 100 cm2 onto a surface of a silicon wafer with screen printing.

A thermodynamic study of the dimerization of cyclopentadiene

1968 ◽  
Vol 21 (7) ◽  
pp. 1789 ◽  
Author(s):  
AG Turnbull ◽  
HS Hull
Keyword(s):  
Liquid Phase ◽  
Rate Constant ◽  
Vapour Pressure ◽  
Boiling Point ◽  
Strain Energy ◽  
Order Rate Constant ◽  
Adiabatic Calorimeter ◽  
Thermodynamic Study ◽  
Heats Of Formation ◽  
Kcal Mole

The heat of dimerization of cyclopentadiene to endo-dicyciopentadiene in the liquid phase at 25� was measured in an adiabatic calorimeter to be -9.22 � 0.3 kcal/mole monomer. The rate of dimerization in the liquid phase at 25� was followed with a dilatometer and the initial second-order rate constant found to be 4.99 x 10-5. mole-l min-l. The vapour pressure of endo-dicyclopentadiene, measured by a boiling point method in the range 77.5-149.6�, gave the relation (p in torr): RInp ? 11342/T -2.6505In T + 54.7855 The standard heats of formation of solid, 31.1 � 0.5 kcal/mole, and gaseous, 42.2 � 0. 6 kcal/mole, endo-dicyclopentadiene were derived, and the strain energy and dimerization equilibria discussed.

Effect of organic solvents and ionic liquids on resolution of 2-epoxyhexane by whole cells ofRhodotorula glutinisin a two-liquid phase system

2013 ◽  
Vol 89 (4) ◽  
pp. 522-527 ◽  
Author(s):  
Michiaki Matsumoto ◽  
Takashi Sugimoto ◽  
Yudai Ishiguro ◽  
Hiroyuki Yamaguchi ◽  
Kazuo Kondo
Keyword(s):  
Ionic Liquids ◽  
Liquid Phase ◽  
Organic Solvents ◽  
Phase System ◽  
Whole Cells

Liquid-Phase Exfoliation of Few-Layer Graphene and Effect of Sonication Time on Concentration of Produced Few Layer Graphene

2017 ◽  
Vol 14 ◽  
pp. 17-24 ◽  
Author(s):  
Syed Sajid Ali Shah ◽  
Habib Nasir
Keyword(s):  
Liquid Phase ◽  
Cost Effective ◽  
Production Method ◽  
Commercial Production ◽  
Sonication Time ◽  
High Concentration ◽  
Layer Graphene ◽  
Uv Visible ◽  
Liquid Phase Exfoliation ◽  
Few Layer Graphene

Although graphene has been produced by various methods at lab scale, however, its cost effective mass production method is still a challenge. Graphene has been produced by liquid phase exfoliation, which is the most probable method for commercial production of graphene for various industrial applications.This paper reports high concentration production of few-layer graphene in DMSO (dimethyl sulfoxide) as solvent through liquid phase exfoliation assisted with sonication. The temperature was kept below 30oC. SEM, AFM, and XRD were used to characterize the produced graphene. SEM results confirm the production of few-layer graphene. EDX analysis shows that the graphene surface is free from oxides and impurities. AFM results also confirm the production of few-layer graphene. The UV-visible spectrophotometer was used to determine the concentration of the produced graphene, and the investigations demonstrate that the graphene production was increased by increasing the sonication time. There exist a linear relationship between the amount of produced graphene and sonication time for supplying energy during sonication.

Solid–Liquid Phase Equilibrium and Solubility of Dibenzo[b,d]furan and 9H-Fluoren-9-one in Organic Solvents

2012 ◽  
Vol 57 (4) ◽  
pp. 1279-1287 ◽  
Author(s):  
Yufeng Wei ◽  
Leping Dang ◽  
Xiangyang Zhang ◽  
Weimin Cui ◽  
Hongyuan Wei
Keyword(s):  
Phase Equilibrium ◽  
Liquid Phase ◽  
Organic Solvents ◽  
Solid Liquid
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