THERMODYNAMIC EXCESS FUNCTIONS IN THE SYSTEMS ACETIC ACID – WATER AND ACETIC ACID – CHLOROFORM

1965 ◽  
Vol 43 (8) ◽  
pp. 2448-2450 ◽  
Author(s):  
J. M. T. M. Gieskes

not available

1987 ◽  
Vol 42 (4) ◽  
pp. 341-351
Author(s):  
Karl Hensen ◽  
Jens Gaede

By analyzing the cooling curves and the resulting melting point diagrams of the chloromethylsilane- pyridazine and pyrazine systems the existence of the incongruently melting addition compounds CH3SiCl3 • Pyridazine, (CH3)2SiCl2 • (Pyridazine)2, (CH3)3SiCl • (Pyridazine)2, CH3SiCl3 • (Pyrazine)2, (CH3)2SiCl2 • (Pyrazine)2 , (CH3)3SiCl • (Pyrazine)2 was proved. By electro-optical measurements of the turbidity point it was proved that the system (CH3)3SiCl- Pyridazine exhibits a miscibility gap which intersects the liquidus curve of the amine. Based on certain approximations it was possible to fit thermodynamic functions to the experimental results to obtain the excess data of mixing of the corresponding systems. These data allow for a more profound understanding of the Lewis-acid base behaviour of the silanes and amines.Chloromethylsilanes, Pyridazine, Pyrazine, Phase Diagrams, Addition Compounds, Thermodynamic Excess Functions


2007 ◽  
Vol 111 (31) ◽  
pp. 9270-9280 ◽  
Author(s):  
Toshiyuki Takamuku ◽  
Yasuhiro Kyoshoin ◽  
Hiroshi Noguchi ◽  
Shoji Kusano ◽  
Toshio Yamaguchi

2011 ◽  
Vol 51 (5) ◽  
pp. 819-825 ◽  
Author(s):  
Housheng Hong ◽  
Longxiang Chen ◽  
Qingwen Zhang ◽  
Zheran Zhang

1974 ◽  
Vol 52 (11) ◽  
pp. 1013-1017 ◽  
Author(s):  
William H. Cruickshank ◽  
Barry L. Malchy ◽  
Harvey Kaplan

Thiolysis of an O-dinitrophenyl-tyrosyl peptide results in an increased solubility in the stationary phase of a n-butanol – acetic acid – water – pyridine (15:3:12:10) (BAWP) paper chromatographic system. It is shown that this property can be used to form the basis of a diagonal paper chromatographic purification of tyrosyl peptides from enzymatic digests of proteins. The amino groups of the protein are first reacted with citraconic anhydride and then the citraconyl protein is reacted with 1-fluoro-2,4-dinitrobenzene. The dinitrophenyl-citraconyl protein is subjected to enzymatic digestion, applied to a strip of Whatman 3 MM paper, thiolyzed with 5% 2-mercaptoethanol in acetone, and subjected to chromatography using BAWP as solvent. A guide strip is removed, thiolyzed with 5% 2-mercaptoethanol in 25% pyridine, and resubjected to chromatography in BAWP at right angles to the original direction of chromatography. The tyrosyl peptides are displaced off the diagonal towards the origin. The off-diagonal peptides are isolated from the original chromatogram by thiolysis and chromatography using the diagonal chromatogram to locate the positions of the dinitrophenyl-tyrosyl peptides.


Author(s):  
Olga V. Yatsenkova ◽  
Andrei M. Skripnikov ◽  
Boris N. Kuznetsov

The work describes a one-stage method of cellulose obtaining from fir wood based on peroxide delignification of wood under mild conditions (100 °C, atmospheric pressure) in the presence of acetic acid, water and catalyst of 2% wt. H2SO4. The possibility of obtaining cellulose with a residual lignin content <1% wt. at a low concentration of hydrogen peroxide (3% wt.) in the reaction medium was established. The optimal concentrations of reagents (Н2О2 – 3% wt., CH3COOH – 38.9% wt.) and the duration of the process (4 h) were determined by experimental and calculation methods. This conditions provide a high yield of cellulose product (≥45% wt.) with a low content of residual lignin (<1% wt.). The composition and structure of fir cellulose was studied by chemical analysis and by FTIR and SEM methods. The cellulosic product which was obtained in optimal process conditions is high-quality cellulose


2007 ◽  
Vol 23 (5) ◽  
pp. 323-328 ◽  
Author(s):  
P. Dakshinamurty ◽  
V. Subrahmanyam ◽  
M. Narsimha Rao

Sign in / Sign up

Export Citation Format

Share Document