A new compounds of 2,4-substituted-1,3- thiazole containing amines [I] and [II], Schiff bases [IV] and [V], amides [VI]-[X],esters [XI] - [XIII], thiazolidinones [XIV]-[XVIII] and 1,3-oxazepines [XIX]-[XXV] were Synthesized and characterized by melting points, FTIR spectroscopy, elemental analysis, 1HNMR,13CNMR, dept135and Mass spectroscopy. The liquid crystalline properties of the synthesized compounds were verified by using hot-stage polarizing optical microscopy (POM) and differential scanning calorimeter (DSC). The compound [I] was found to be nematic textures (N). The first series of this study [II]n display only enantiotropic nematic phase when n=1-5 while the compounds with n =6-8 display two mesophasese smectic C(SmC) and nematic phases(N). All compounds of series [IV]n were found to be enantiotropic nematic phase. Compounds[VI]a and[VI]b showed both semctic and nematic phases. Compounds [XI]a, b and [XIII]a, b showed only nematic texture but the compounds [XI]c and [XIII]c did not show any liquid crystalline properties. All compounds of series [XVII]n with n=1,3-7 display only nematic texture but compound with n=8 showed semactic C phase (SmC) in addition of ne
In this study, a mathematical model for the kinetics of solute transport in liquid membrane systems (LMSs) has been formulated. This model merged the mechanisms of consecutive and reversible processes with a “semi-derived” diffusion expression, resulting in equations that describe solute concentrations in the three sections (donor, acceptor and membrane). These equations have been refined into linear forms, which are satisfying in the special conditions for simplification obtaining the important kinetic constants of the process experimentally.
A hydrophilic interaction chromatography has been investigated to separate 2-deoxycytidine chosen for nucleoside. A small molecule with specific features for human serum samples was 2-deoxycytidine tested. 2-deoxycytidine has been applied to self-made stationary hydrophilic phases (ZIC1 and ZIC5). The deoxycytidine (dCD) retention was investigated with varying concentrations of sodium acetate buffer, acetonitrile%, and pH. The results confirmed the hydrophilicity of 2-deoxycytidine. The exchanger retention mechanism was studied taking into account 2-deoxycytidine used for describing the interaction of hydrophilic and cation. For both ZIC1 and ZIC5 exchangers, we described and discussed the influence of chromatographic conditions (co
... Show MoreExperiments were conducted to study axial liquid dispersion coefficient in slurry bubble column of 0.15 m inside diameter and 1.6 m height using perforated plate gas distributor of 54 holes of a size equal to 1 mm diameter and with a 0.24 free area of holes to the cross sectional area of the column. The three phase system consists of air, water and PVC used as the solid phase. The effect of solid loading (0, 30 and 60 kg/m3) and solid diameter (0.7, 1.5 and 3 mm) on the axial liquid dispersion coefficient at different axial location (25, 50 and 75 cm) and superficial gas velocity covered homogeneous-heterogeneous flow regime (1-10 cm/s) were studied in the present work. The results show that the axial liquid dispersion coeffic
... Show MoreSUMMARY. – Absorption, flourescence, quantum yield and lifetime of rhodamine B in chloroform, methanol and dimethyl sulfoxide were measured. A comparison was done of these quantities with those for solid solutions, which are obtained by mixing constant volume proportions of dye at a concentration of 1×10–4M/l with different volume proportions from the concentrated solution of polymer in chloroform and dimethyl sulfoxide. The results showed that the addition of polymer to liquid concentrated solutions (1×10–4M/l) of rhodamine B dye from expecting, which leads to development of active medium for laser dye at high concentration, increase the spectra shift toward high energies, and the luminescence quantum yield but decreasing radiative
... Show MoreThe removal of Anit-Inflammatory drugs, namely; Acetaminophen (ACTP), from wastewater by bulk liquid membrane (BLM) process using Aliquat 336 (QCl) as a carrier was investigated. The effects of several parameters on the extraction efficiency were studied in this research, such as the initial feed phase concentration (10-50) ppm of ACTP, stripping phase (NaCl) concentration (0.3,0.5,0.7 M), temperature (30-50oC), the volume ratio of feed phase to membrane phase (200-400ml/80ml), agitation speed of the feed phase (75-125 rpm), membrane stirring speed (0, 100, 150 rpm), carrier concentration (1, 5, 9 wt%), the pH of feed (2, 4, 6, 8, 10), and solvent type (CCl4 and n-Heptane). The study shows that high ext
... Show MoreRoom temperature ionic liquids show potential as an alternative to conventional organic membrane solvents mainly due to their properties of low vapour pressure, low volatility and they are often stable. In the present work, the technical feasibilities of room temperature ionic liquids as bulk liquid membranes for phenol removal were investigated experimentally. In this research several hydrophobic ionic liquids were synthesized at laboratory. These ionic liquids include (1-butyl-3-methylimidazolium bis (trifluoromethylsulfonyl) imide[Bmim][NTf2], 1-Hexyl-3-methylimidazolium bis (trifluoromethylsulfonyl) imide[Hmim][NTf2], 1-octyl-3-methylimidazolium bis (trifluoromethylsulfonyl)imide[Omim][NTf2],1‐butyl
... Show Moreيهدف البحث الحالي إلى الاستفادة من القهوة المستهلكة , كمادة وسيطة حيث تعد القهوة المستهلكة من المخلفات المضرة للبيئة الاستخراج الكافيين الطبيعي والذي يعد مادة ذات نشاط حيوي واهمية, وتحديد العوامل الفعالة في كفاءة عملية الاستخلاص من حيث تركيز الكافيين. تضمنت المتغيرات الرئيسية المدروسة وقت الاستخلاص 0-150 دقيقة ، ودرجة الحرارة 25-55 درجة مئوية ، وسرعة الخلط 180-450 دورة في الدقيقة ، ودرجة الحموضة العالق
... Show MoreAbsorption, fluorescence, quantum yield and lifetime of rhodamine 6G in chloroform, methanol and dimethyl sulfoxide were measured. From a comparison of these quantities, with those for solid solutions (solid solutions are obtained by mixing constant volume proportions of dye at a concentration of 1*10-4M/l with different volume proportions from the concentrated solution of polymer in chloroform and dimethyl sulfoxide). The results showed that the addition of polymer to liquid concentrated solutions (1*10-4M/l )of rhodamine 6G dye from expecting [which leading to development active medium for laser dye at high concentration] increase the spectra shift toward high energies, and the luminescence quantum yield but decreasing radiative lifetim
... Show MoreFive new ceftazidime derivatives were designed and synthesized in an attempt to improve the acid stability and may increase the spectrum of ceftazidime. The synthesized compounds included; Schiff base of ceftazidime (compound 1), ceftazidime lysine amide Schiff base (compound 2), ceftazidime lysine amide (compound 3), ceftazidime-di-lysine amide Schiff base (compound 4) and ceftazidime-di-lysine amide (compound 5). New ceftazidime derivatives were successfully prepared characterized and identified using spectral and elemental microanalysis (CHNS) analyses and the results comply with the calculated measurements.
Compounds 1 and 2 were subjected to a stability study in phosphate buffer (0.2M, pH 7.4) and in KCl/HCl buffer (0.
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