Electrolytic Interaction of Nylon with Sodium Hydroxide Solutions at Different Temperatures

1953 ◽  
Vol 57 (3) ◽  
pp. 370-375 ◽  
Author(s):  
Frederick T. Wall ◽  
Patricia M. Saxton
Keyword(s):  
Sodium Hydroxide ◽  
Different Temperatures

scholarly journals Kinetics and Mechanism of the Change of the 4-Nitrobenzylthio-System into 4,4′-Diformylazoxybenzene in Alkaline Dioxane-Water Media

1985 ◽  
Vol 40 (11) ◽  
pp. 1128-1132
Author(s):  
Y. Riad ◽  
Adel N. Asaad ◽  
G.-A. S. Gohar ◽  
A. A. Abdallah
Keyword(s):  
Acetic Acid ◽  
Sodium Hydroxide ◽  
Rate Constants ◽  
Main Product ◽  
Reaction Medium ◽  
Aqueous Dioxane ◽  
Proton Abstraction ◽  
First Order ◽  
Water Media ◽  
Different Temperatures

Sodium hydroxide reacts with α -(4-nitrobenzylthio)-acetic acid in aqueous-dioxane media to give 4,4'-diformylazoxybenzene as the main product besides 4,4'-dicarboxyazoxybenzene and a nitrone acid. This reaction was kinetically studied in presence of excess of alkali in different dioxane-water media at different temperatures. It started by a fast reversible a-proton abstraction step followed by two consecutive irreversible first-order steps forming two intermediates (α -hydroxy, 4-nitrosobenzylthio)-acetic acid and 4-nitrosobenzaldehyde. The latter underwent a Cannizzaro's reaction, the products of which changed in the reaction medium into 4,4'-diformylazoxybenzene and 4,4'-dicarboxyazoxybenzene. The rate constants and the thermodynamic parameters of the two consecutive steps were calculated and discussed. A mechanism was put forward for the formation of the nitrone acid.Other six 4-nitrobenzyl, aryl sulphides were qualitatively studied and they gave mainly 4,4'-diformylazoxybenzene beside 4,4'-dicarboxyazoxybenzene or its corresponding azo acid.

Synthesis, Photoluminescence and Bio-Targeting Applications of Blue Graphene Quantum Dots

2016 ◽  
Vol 16 (4) ◽  
pp. 3457-3467 ◽  
Author(s):  
Jigang Wang ◽  
Ji Zhou ◽  
Wenhua Zhou ◽  
Jilong Shi ◽  
Lun Ma ◽  
...  
Keyword(s):  
Quantum Dots ◽  
Graphene Oxide ◽  
Sodium Hydroxide ◽  
Heating Temperature ◽  
Thin Sheet ◽  
Graphene Quantum Dots ◽  
Photoluminescence Intensity ◽  
Cytotoxic Effects ◽  
Different Temperatures ◽  
Blue Photoluminescence

Chemical derived graphene oxide, an atomically thin sheet of graphite with two-dimensional construction, offers interesting physical, electronic, thermal, chemical, and mechanical properties that are currently being explored for advanced physics electronics, membranes, and composites. Herein, we study graphene quantum dots (GQD) with the blue photoluminescence under various parameters. The GQD samples were prepared at different temperatures, and the blue photoluminescence intensity of the solution improved radically as the heating temperatures increased. Concerning PL peak and intensity of the quantum dots, the results demonstrated dependence on time under heating, temperature of heating, and pH adjusted by the addition of sodium hydroxide. After hydrothermal synthesis routes, the functional groups of graphene oxide were altered the morphology showed the stacking configuration, and self-assembled structure of the graphene sheets with obvious wrinkles appeared at the edge structures. In addition, absorption, PL, and PLE spectra of the graphene quantum dots increase with different quantities of sodium hydroxide added. Finally, using GQD to target PNTIA cells was carried out successfully. High uptake efficiency and no cytotoxic effects indicate graphene quantum dots can be suitable for bio-targeting.

Preparing Sodium Methoxide from Sodium Hydroxide by Reaction Coupling with Separation Processes

2014 ◽  
Vol 986-987 ◽  
pp. 101-105 ◽  
Author(s):  
Meng Xiong ◽  
Cheng Xi Wang ◽  
Dan Dan Shao
Keyword(s):  
Sodium Hydroxide ◽  
Sodium Methoxide ◽  
Batch Reactor ◽  
Coupling Reaction ◽  
Sodium Hydroxide Concentration ◽  
Separation Processes ◽  
Reaction Phase ◽  
Different Temperatures ◽  
Reaction Coupling ◽  
Good Agreement

Preparing sodium methoxide by reacting sodium hydroxide with methanol was investigated. The chemical equilibrium constant was small. Removing water out of the reaction phase could drive the reaction to produce more sodium methoxide. The experiments were carried out at different temperatures and 1 atm in semi-batch reactor by liquid evaporating to remove water. The effects of initial sodium hydroxide concentration and liquid evaporating speed were discussed. A mathematical model coupling reaction with separation processes was built and the predicted results by the model were in good agreement with experiment results. The model provides useful information for industrial simulation.

Alkali Pretreatment and Acid Hydrolysis of Coconut Pulp and Empty Fruit Bunch to Produce Glucose

2015 ◽  
Vol 74 (7) ◽  
Author(s):  
Noorhalieza Ali ◽  
Che Afifi Che Aziz ◽  
Onn Hassan
Keyword(s):  
Acid Hydrolysis ◽  
Sodium Hydroxide ◽  
Low Cost ◽  
Value Added ◽  
Empty Fruit Bunch ◽  
Alkali Pretreatment ◽  
Infra Red ◽  
Different Temperatures ◽  
Hydrolysis Of ◽  
Value Added Products

Lignocellulose waste has great potential to be converted into value added products sustainably as it is readily available at low cost. The aim of this study is to examine the amount of glucose produced from coconut pulp and coconut empty fruit bunch using acid hydrolysis. Sodium hydroxide pretreatment is carried out at 70oC using different concentrations of sodium hydroxide which are 5%, 10%, 15% and 20% v/v for a duration time of 2 hours. Optimum pretreatment is evaluated using Fourier Transform Infra-Red (FTIR) analysis. It is observed that optimum pretreatment is at 20% v/v sodium hydroxide. The optimum samples are then hydrolysed using concentrations of 5%, 10%, 15% and 20% v/v of sulphuric acid at different temperatures of 30, 50, 70 and 90oC for 2 hours. Glucose concentration is analysed using an ultraviolet (UV) Spectrophotometer. The highest glucose concentrations obtained are 0.895 g/L and 0.550g/L for coconut pulp and coconut empty fruit bunch, respectively at 20% v/v acid concentration and a temperature of 90oC. 

Adosorption of Basic Fuchsin onto Xanthoceras Sorbifolia Bunge Crust Activated Carbon Developed by Sodium Hydroxide

2010 ◽  
Vol 156-157 ◽  
pp. 272-278 ◽  
Author(s):  
Yi Nan Hao ◽  
Xi Ming Wang
Keyword(s):  
Activated Carbon ◽  
Sodium Hydroxide ◽  
Adsorption Isotherms ◽  
Equilibrium Concentration ◽  
Langmuir Equation ◽  
Basic Fuchsin ◽  
Freundlich Isotherms ◽  
Different Temperatures ◽  
Endothermic Process ◽  
Pseudo Second Order

Xanthoceras Sorbifolia Bunge crust was used as source material to make carbon by chemically impregnated by sodium hydroxide、carbonized at 220°C and activated under the protection of the nitrogen. Experiments were carried out as function of contact time, pH (4-10) and temperature (293,303 and 313K). Adsorption isotherms were modeled with the Langmuir and Freundlich isotherms. Adsorption isotherms of Basic Fuchsin on Xanthoceras Sorbifolia Bunge crust activated carbon are consistent with Langmuir equation. The Langmuir monolayer saturation capacities of BF adsorbed onto activated carbon were 286.545, 303.617 and 323.816 mg/g at 293,303, and 313 K, respectively.and adsorption kinetics were found to conform to the pseudo-second-order kinetics with good correlation.Using the equilibrium concentration contents obtained at different temperatures, various thermodynamic parameters,such as △G,△H and △S, have been calculated. The thermodynamics parameters of system indicated spontaneous and endothermic process.

Comparison of Acrylamide and Agar Gels by Freeze-Etching

1977 ◽  
Vol 35 ◽  
pp. 606-607
Author(s):  
Russell L. Steere ◽  
Eric F. Erbe
Keyword(s):  
Electron Microscope ◽  
Sodium Hydroxide ◽  
Sodium Hypochlorite ◽  
Chromic Acid ◽  
Distilled Water ◽  
Thin Sheets ◽  
Acid Cleaning ◽  
Agar Gels ◽  
Freeze Etching ◽  
Water Cut

Thin sheets of acrylamide and agar gels of different concentrations were prepared and washed in distilled water, cut into pieces of appropriate size to fit into complementary freeze-etch specimen holders (1) and rapidly frozen. Freeze-etching was accomplished in a modified Denton DFE-2 freeze-etch unit on a DV-503 vacuum evaporator.* All samples were etched for 10 min. at -98°C then re-cooled to -150°C for deposition of Pt-C shadow- and C replica-films. Acrylamide gels were dissolved in Chlorox (5.251 sodium hypochlorite) containing 101 sodium hydroxide, whereas agar gels dissolved rapidly in the commonly used chromic acid cleaning solutions. Replicas were picked up on grids with thin Foimvar support films and stereo electron micrographs were obtained with a JEM-100 B electron microscope equipped with a 60° goniometer stage.Characteristic differences between gels of different concentrations (Figs. 1 and 2) were sufficiently pronounced to convince us that the structures observed are real and not the result of freezing artifacts.

Observations oh Nucleation and Growth of Voids in Nickel

1970 ◽  
Vol 28 ◽  
pp. 414-415
Author(s):  
J. L. Brimhall ◽  
H. E. Kissinger ◽  
B. Mastel
Keyword(s):  
High Purity ◽  
Growth Stage ◽  
Elevated Temperatures ◽  
Early Growth ◽  
Nucleation And Growth ◽  
Pure Nickel ◽  
Different Temperatures ◽  
Total Fluence ◽  
Neutron Exposure ◽  
Growth Of Voids

Some information on the size and density of voids that develop in several high purity metals and alloys during irradiation with neutrons at elevated temperatures has been reported as a function of irradiation parameters. An area of particular interest is the nucleation and early growth stage of voids. It is the purpose of this paper to describe the microstructure in high purity nickel after irradiation to a very low but constant neutron exposure at three different temperatures.Annealed specimens of 99-997% pure nickel in the form of foils 75μ thick were irradiated in a capsule to a total fluence of 2.2 × 1019 n/cm2 (E > 1.0 MeV). The capsule consisted of three temperature zones maintained by heaters and monitored by thermocouples at 350, 400, and 450°C, respectively. The temperature was automatically dropped to 60°C while the reactor was down.

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