2024-03-29T18:15:40Z
https://ijcce.ac.ir/?_action=export&rf=summon&issue=2033
Iranian Journal of Chemistry and Chemical Engineering
Iran. J. Chem. Chem. Eng.
1021-9986
1021-9986
1987
6
1
Constructing a Body-Fixed Reference Frame for a Polyatomic Molecule
Reza
Islampour
B.T.
Sutcliffe
An attempt is made to show in a straightforward way how a body-fixed frame may be constructed in classical and hence in quantum mechanics for a polyatomic molecule with the aid of which the vibration-rotation behavior of the molecule may be described.
Body-fixed reference frame
Polyatomic molecule
1987
06
01
3
25
https://ijcce.ac.ir/article_12269_136b3098b1d7c31bc31a986c71b8a7c8.pdf
Iranian Journal of Chemistry and Chemical Engineering
Iran. J. Chem. Chem. Eng.
1021-9986
1021-9986
1987
6
1
Epicuticular Wax Alkanes of Scutellaria Lateriflora L. Leaves
Shahram
Yaghmai
Mohammad
Hassanzadeh Khayat
The dried aerial parts of scutellaria lateriflora L. (family Labiatae), have been used for many years as a domestic remedy for epilepsy, hysteria, and nervous tension states. Although several phytochemical investigations have been made regarding the constituents present in this species (i. e. flavonoids, iridoids), none has been recorded concerning the cuticular wax. Using thin-layer chromatography (TLC), column chromatography, gas-liquid chromatography (GLC), and GLC-mass spectrometry, laterifloral collected from Mazandaran province in northern Iran have been analysed. The wax yield was 1.2%. The alkanes fall in the range of C23 to C37 the odd carbon number n-alkanes being predominant. The concentration of branched alkane is low (1.2%). Three homologous series of branched alkanes were identified as 3,9-dimethyl alkanes, 2-methyl alkanes and 3-methyl alkanes.
Epicuticular wax alkanes
Scutellaria lateriflora L
Leaves
1987
06
01
26
30
https://ijcce.ac.ir/article_12270_06a972cc7a2a983ada87b32b4845b539.pdf
Iranian Journal of Chemistry and Chemical Engineering
Iran. J. Chem. Chem. Eng.
1021-9986
1021-9986
1987
6
1
Kinetics and Mechanism of the Substitution of Ligand (Urea) of [Ti(ur)6]3+ by H2O and SCN¯ in Ethanol Solution
A.
Kamkar
J.P.
Day
The kinetics of substitution of [Ti(ur)6]3+ by H2O and SCN¯ ion in ethanol solution have been measured spectrophotometrically by stopped-flow method. Water is a good nucleophile toward Ti(III) substrates. Even the solvent ethanol appears to be a poor ligand when compared to water. Substitution, in general follows two parallel pathways: "direct" (second order) reaction and solvolysis followed by rapid substitution (first order). Both mechanisms are important for H2O substitution, but for SCN¯ reaction is much more rapid and proceeds entirely by the "direct" route, probably because of the greater nucleophilic strength of SCN¯ V.S. H2O.
Kinetics
substitution
Ligand (Urea)
Ethanol Solution
1987
06
01
31
37
https://ijcce.ac.ir/article_12271_e97b4991f6834000312f23de43cf1970.pdf
Iranian Journal of Chemistry and Chemical Engineering
Iran. J. Chem. Chem. Eng.
1021-9986
1021-9986
1987
6
1
A New Model for Designing Gas Distribution Networks
A new model for the design of the city gas distribution network has been presented. On the basis of mass flow rates and pressure balances a nonlinear system of equation is obtained. A method for solving the latter is outlined which gives accurate results. Also, this method, when compared to the other accessible ones, takes less computer time. Finally in this method the actual length of network and pipe diameter can be considered. This is in contrast to the other methods in which certain quantities called "equivalent length" for different pipe size should be used.
design
model
Gas distribution networks
1987
06
01
38
43
https://ijcce.ac.ir/article_12272_6da7117bd2b3e09abe42b2baccee624d.pdf
Iranian Journal of Chemistry and Chemical Engineering
Iran. J. Chem. Chem. Eng.
1021-9986
1021-9986
1987
6
1
The Effect of Osmotic Dehydration on Reverse Osmosis Membrane Performance
Mohammad Nabi
Sarbolouki
Hossein
Samimi
Akin type (asymmetric) reverse osmosis membranes undergo an irreversible osmotic dehydration upon coming into contact (skin side) with salt solutions. The extent of consequent changes (in appearance; decrease in linear dimension, water flux and salt rejection) are dependent on the salt concentration. These observations are correlated with the expected morphological changes taking place during dehydration (drying). It is thus speculated that such phenomena may inadvertently happen during the start-up phase of new RO units treating high salinity waters. To avert such event, it is recommended the start-up phase to be programmed in such a way that feed concentration is gradually elevated to its ultimate level.
Osmotic dehydration
Reverse osmosis membrane
Performance
1987
06
01
44
46
https://ijcce.ac.ir/article_12277_f6ae3aab41143f02cb561e2ef2fa3c92.pdf