The structure of aqueous sodium hydroxide solutions: A combined solution x-ray diffraction and simulation study

2008 ◽  
Vol 128 (4) ◽  
pp. 044501 ◽  
Author(s):  
Tünde Megyes ◽  
Szabolcs Bálint ◽  
Tamás Grósz ◽  
Tamás Radnai ◽  
Imre Bakó ◽  
...  
Keyword(s):  
Sodium Hydroxide ◽  
Simulation Study ◽  
Aqueous Sodium Hydroxide ◽  
X Ray Diffraction ◽  
Aqueous Sodium ◽  
X Ray ◽  
Combined Solution

Orthoamide und Iminiumsalze, LXXIX [1]. N-[w-(Dimethylamino)alkyl]-N´,N´,N´´,N´´-tetramethylguanidine und davon abgeleitete Guanidiniumsalze: Synthese und Kristallstrukturen/ Orthoamides and Iminium Salts, LXXIX [1]. N-[w-(Dimethylamino)alkyl]-N´,N´,N´´,N´´- tetramethylguanidines and Salts Derived therefrom: Synthesis and Crystal Structures

2012 ◽  
Vol 67 (7) ◽  
pp. 685-698 ◽  
Author(s):  
Ioannis Tiritiris ◽  
Willi Kantlehner
Keyword(s):  
Sodium Hydroxide ◽  
Crystal Structures ◽  
Dimethyl Sulfate ◽  
Aqueous Sodium Hydroxide ◽  
Chloride Ions ◽  
Sodium Tetraphenylborate ◽  
X Ray Diffraction ◽  
Aqueous Sodium ◽  
X Ray ◽  
Iminium Salts

N-(ω-Dimethylammonioalkyl)-N´,N´,N´´,N´´-tetramethylguanidinium-dichlorides 5a, b are obtained from the chloroformamidinium salt 2 and diamines 3a, b. Their crystal structures reveal that the guanidinium ions are associated with the chloride ions via N-H· · ·Cl hydrogen bonds. By deprotonation of 5a, b with one equivalent of sodium hydroxide, the guanidinium chlorides 4a, b are accessible, and a further deprotonation leads to the aminoguanidines 6a, b, which hydrolyze in the presence of excessive aqueous sodium hydroxide to give the aminoalkylureas 7a, b. The salts 9a, b and 10a, b were synthesized from 4a, b and 5a, b, respectively, by anion metathesis by means of sodium tetraphenylborate. 7a reacts with dimethyl sulfate to give the waxy ammonium salt 11a, which was converted to the crystalline tetraphenylborate salt 12a. The crystal structures of all the tetraphenylborates were determined by single-crystal X-ray diffraction analysis.

Selective O-Demethylation of 5,8-Dihydroxy-2,3-Dimethoxy-6-Methylnaphtho-1,4-Quinone: The Crystal Structures of 5,8-Dihydroxy-2,3-Dimethoxy-6-Methylnaphtho-1,4-Quinone and 2,5,8-Triacetoxy-3-Methoxy-6-Methylnaphtho-1,4-Quinone

1987 ◽  
Vol 40 (7) ◽  
pp. 1191 ◽  
Author(s):  
JR Cannon ◽  
Y Matsuki ◽  
VA Patrick ◽  
AH White
Keyword(s):  
Crystal Structure ◽  
Least Squares ◽  
Sodium Hydroxide ◽  
Crystal Structures ◽  
Hydrolysis Product ◽  
Aqueous Sodium Hydroxide ◽  
X Ray Diffraction ◽  
Aqueous Sodium ◽  
X Ray ◽  
Least Squares Techniques

It has been confirmed that treatment of 5,8-dihydroxy-2,3-dimethoxy-6-methylnaphtho-1,4- quinone (1) with dilute aqueous sodium hydroxide leads to selective O- demethylation. The hydrolysis product has been identified as 2,5,8-trihydroxy-3-methoxy-6-methylnaphtho1,4- quinone (3) from the crystal structure of the corresponding triacetate (4). The crystal structures of 5,8-dihydroxy-2,3-dimethoxy-6-methylnaphtho-1,4-quinone (1) and 2,5,8-triacetoxy-3-methoxy-6-methylnaphtho-1,4-quinone (4) were determined by X-ray diffraction; diffractometer data at 295 K were refined by least squares techniques to residuals of 0.074 (583 'observed' reflections) for (1) and 0.049 (2005) for (4). Crystals of (1) are monoclinic, P2l/c, a 3.873(4), b 20.21(1), c 15.OO(2) �, β 96.05(6)�, Z 4. Crystals of (4) are also monoclinic, P2l/c, a 10.532(5), b 14.596(6), c 12.097(6) �, β 109.74(4)�, Z 4.

Sedimentary Clays as Geopolymer Precursor

2018 ◽  
Vol 39 ◽  
pp. 97-111
Author(s):  
F. Mostefa ◽  
Nasr Eddine Bouhamou ◽  
H.A. Mesbah ◽  
Salima Aggoun ◽  
D. Mekhatria
Keyword(s):  
Sodium Hydroxide ◽  
Mineralogical Composition ◽  
Cementitious Materials ◽  
Raw Material ◽  
X Ray Diffraction ◽  
Calcination Time ◽  
Calorimetric Analysis ◽  
X Ray ◽  
Before And After ◽  
Mechanical Performances

This work aims to study the feasibility of making a geopolymer cement based on dredged sediments, from the Fergoug dam (Algeria) and to evaluate their construction potential particularly interesting in the field of special cementitious materials. These sediments due to their mineralogical composition as aluminosilicates; are materials that can be used after heat treatment. Sedimentary clays were characterized before and after calcination by X-ray diffraction, ATG / ATD, spectroscopy (FTIR) and XRF analysis. The calcination was carried out on the raw material sieved at 80 μm for a temperature of 750 ° C, for 3.4 and 5 hours. The reactivity of the calcined products was measured using isothermal calorimetric analysis (DSC) on pastes prepared by mixing an alkaline solution of sodium hydroxide (NaOH) 8 M in an amount allowing to have a Na / Al ratio close to 1 (1: 1). Also, cubic mortar samples were prepared with a ratio L / S: 0.8, sealed and cured for 24 hours at 60 ° C and then at room temperature until the day they were submited to mechanical testing. to check the extent of geopolymerization. The results obtained allowed to optimize the calcination time of 5 hours for a better reactivity of these sediments, and a concentration of 8M of sodium hydroxide and more suitable to have the best mechanical performances.

scholarly journals Triple Helix of Scleroglucan in Dilute Aqueous Sodium Hydroxide

1981 ◽  
Vol 13 (12) ◽  
pp. 1135-1143 ◽  
Author(s):  
Toshio Yanaki ◽  
Takemasa Kojima ◽  
Takashi Norisuye
Keyword(s):  
Sodium Hydroxide ◽  
Triple Helix ◽  
Aqueous Sodium Hydroxide ◽  
Aqueous Sodium
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