National Information and Documentation Centre (NIDOC), Academy of Scientific Research and Technology, ASRT
Egyptian Journal of Chemistry
0449-2285
2357-0245
53
1
2010
03
02
Effect of Sm3+ Ions on the Transport and Sublattice Magnetization of Perovskite System
1
15
EN
10.21608/ejchem.2010.1201
<span style="font-size: xx-small;">PEROVSKITE compounds (La</span><span style="font-size: xx-small;">1-x</span><span style="font-size: xx-small;">Sm</span><span style="font-size: xx-small;">x</span><span style="font-size: xx-small;">)</span><span style="font-size: xx-small;">0.7 </span><span style="font-size: xx-small;">Ca</span><span style="font-size: xx-small;">0.3</span><span style="font-size: xx-small;">MnO</span><span style="font-size: xx-small;">3 </span><span style="font-size: xx-small;">0 ≤ x ≤ 0.14 </span>
…. were prepared using the double sintering ceramic technique. The measurement of the magnetic susceptibility at different temperatures as a function of the magnetic field intensity showed the change of the state from completely ordered to completely disordered state at T
<span style="font-size: xx-small;">C </span><span style="font-size: xx-small;">which shifts to lower value by increasing Sm content. The tolerance factor decreases with increasing Sm concentration. Resistivity measurements indicate the disappearance of the related peaks with increasing Sm content. The large increase in the resistivity below 530K is related to the spin transition of Mn</span><span style="font-size: xx-small;">3+ </span><span style="font-size: xx-small;">ions from high to low state. </span>
Transport phenomena,Magnetic properties,AC resistivity and Perovskite
https://ejchem.journals.ekb.eg/article_1201.html
https://ejchem.journals.ekb.eg/article_1201_62f0a8460a7dbc6e35d33764157072f4.pdf
National Information and Documentation Centre (NIDOC), Academy of Scientific Research and Technology, ASRT
Egyptian Journal of Chemistry
0449-2285
2357-0245
53
1
2010
03
02
Focus on the Synthesis and Reactions of Some New Pyridine Carbonitrile Derivatives as Antimicrobial and Antioxidant Agents
17
35
EN
10.21608/ejchem.2010.1202
<span style="font-size: xx-small;">3-(4-CHLOROPHENYL)-1-(2,4-dichlorophenyl)-propen-1-one (1) was prepared and reacted with active methylene compound, ethyl cyanoacetate in the presence of ammonium acetate to give the corresponding pyridine carbonitrile (2). The behavior of compound 2 towards phosphorous pentasulfide, phosphorous oxychloride and some acyclic-sugars has been investigated and afforded compounds 3, 4 and 5a-d, respectively. The thioxo-pyridine carbonitrile (3) reacted with different halo compounds namely: methyl iodide, ethyl chloroacetate, some acyclic sugars to afford 6, 7 and 8a-c, respectively. Treatment of compound 3 with acrylonitrile afforded compound 9. Reaction of the thiosulfanyl 6 with hydrazine hydrate gave the hydrazino derivative 10 while reaction of 7 with the same reagents gave the acid hydrazide 11. Also, compound 4 reacted with different nucleophiles to afford compounds 10, 12-14. Condensation of compound 10 with ethyl acetoacetate, acetyl acetone, acetic anhydride, p-chlorobenzaldehyde afforded compounds 15-18, respectively. Moreover, compound 10 reacted with carbon disulfide to afford compound 19. Finally, condensation of compound 10 with aldehydo-sugar namely: D-glucose gave the corresponding acyclic nucleoside 20. Furthermore, biological evaluation of some prepared compounds has been assessed and some of them revealed promising antimicrobial and antioxidant activity. </span>
Pyridines,Nicotinonitrile,Pyrazolopyridine,Triazolopyr-idine,Acyclic nucleosides,Antimicrobial activity and Antioxidant agent
https://ejchem.journals.ekb.eg/article_1202.html
https://ejchem.journals.ekb.eg/article_1202_74d9b0544ffba71ca39126249b9a2805.pdf
National Information and Documentation Centre (NIDOC), Academy of Scientific Research and Technology, ASRT
Egyptian Journal of Chemistry
0449-2285
2357-0245
53
1
2010
03
02
Effects of Ferric and Chromic Salts in Physicochemical, Surface and Catalytic Properties of Pure and Doped Fe2O3-Cr2O3 System
37
59
EN
10.21608/ejchem.2010.1203
FERRIC/CHROMIC mixed oxides having the formula 0.85 Fe <span style="font-family: Times New Roman; font-size: xx-small;"><span style="font-family: Times New Roman; font-size: xx-small;">2</span></span><span style="font-family: Times New Roman; font-size: xx-small;"><span style="font-family: Times New Roman; font-size: xx-small;">O</span></span><span style="font-family: Times New Roman; font-size: xx-small;"><span style="font-family: Times New Roman; font-size: xx-small;">3</span></span><span style="font-family: Times New Roman; font-size: xx-small;"><span style="font-family: Times New Roman; font-size: xx-small;">: 0.15 0.15CCr</span></span><span style="font-family: Times New Roman; font-size: xx-small;"><span style="font-family: Times New Roman; font-size: xx-small;">2</span></span><span style="font-family: Times New Roman; font-size: xx-small;"><span style="font-family: Times New Roman; font-size: xx-small;">O</span></span><span style="font-family: Times New Roman; font-size: xx-small;"><span style="font-family: Times New Roman; font-size: xx-small;">3 </span></span><span style="font-family: Times New Roman; font-size: xx-small;"><span style="font-family: Times New Roman; font-size: xx-small;">were obtained by thermal decomposition of the mixed hydroxides prepared from mixed nitrate and sulphate solutions using NH</span></span><span style="font-family: Times New Roman; font-size: xx-small;"><span style="font-family: Times New Roman; font-size: xx-small;">4</span></span><span style="font-family: Times New Roman; font-size: xx-small;"><span style="font-family: Times New Roman; font-size: xx-small;">OH. Pure mixed hydroxides were heated at 500°C .The doped solids were prepared by treating the precipitated hydroxides with different amounts of Li</span></span><span style="font-family: Times New Roman; font-size: xx-small;"><span style="font-family: Times New Roman; font-size: xx-small;">2</span></span><span style="font-family: Times New Roman; font-size: xx-small;"><span style="font-family: Times New Roman; font-size: xx-small;">O and K</span></span><span style="font-family: Times New Roman; font-size: xx-small;"><span style="font-family: Times New Roman; font-size: xx-small;">2</span></span><span style="font-family: Times New Roman; font-size: xx-small;"><span style="font-family: Times New Roman; font-size: xx-small;">O (0.5, 0.75 and 1.5 mol %) followed by calcination at 500°C. The techniques employed were XRD, N</span></span><span style="font-family: Times New Roman; font-size: xx-small;"><span style="font-family: Times New Roman; font-size: xx-small;">2</span></span><span style="font-family: Times New Roman; font-size: xx-small;"><span style="font-family: Times New Roman; font-size: xx-small;">-adsorption and oxidation of CO by O</span></span><span style="font-family: Times New Roman; font-size: xx-small;"><span style="font-family: Times New Roman; font-size: xx-small;">2 </span></span><span style="font-family: Times New Roman; font-size: xx-small;"><span style="font-family: Times New Roman; font-size: xx-small;">at 200-300°C. The results revealed that pure and doped systems consisted of nanocrystalline phases having crystallite size varying between 8-64 nm depending on the nature of ferric and chromic salts used and dopant </span></span><span style="font-family: Times New Roman; font-size: xx-small;" lang="JA"><span style="font-family: Times New Roman; font-size: xx-small;" lang="JA">concentration. Pure mixed solids consisted of a mixture of α and γ</span></span><span style="font-family: Times New Roman; font-size: xx-small;"><span style="font-family: Times New Roman; font-size: xx-small;">-Fe</span></span><span style="font-family: Times New Roman; font-size: xx-small;"><span style="font-family: Times New Roman; font-size: xx-small;">2</span></span><span style="font-family: Times New Roman; font-size: xx-small;"><span style="font-family: Times New Roman; font-size: xx-small;">O</span></span><span style="font-family: Times New Roman; font-size: xx-small;"><span style="font-family: Times New Roman; font-size: xx-small;">3 </span></span><span style="font-family: Times New Roman; font-size: xx-small;"><span style="font-family: Times New Roman; font-size: xx-small;">phase whose crystallite size decreases by increasing the dopant concentrations. K</span></span><span style="font-family: Times New Roman; font-size: xx-small;"><span style="font-family: Times New Roman; font-size: xx-small;">2</span></span><span style="font-family: Times New Roman; font-size: xx-small;"><span style="font-family: Times New Roman; font-size: xx-small;">O-doping of the investigated systems resulted in the formation of K</span></span><span style="font-family: Times New Roman; font-size: xx-small;"><span style="font-family: Times New Roman; font-size: xx-small;">2</span></span><span style="font-family: Times New Roman; font-size: xx-small;"><span style="font-family: Times New Roman; font-size: xx-small;">FeO</span></span><span style="font-family: Times New Roman; font-size: xx-small;"><span style="font-family: Times New Roman; font-size: xx-small;">4 </span></span><span style="font-family: Times New Roman; font-size: xx-small;"><span style="font-family: Times New Roman; font-size: xx-small;">together with ferric oxide phases. Li</span></span><span style="font-family: Times New Roman; font-size: xx-small;"><span style="font-family: Times New Roman; font-size: xx-small;">2</span></span><span style="font-family: Times New Roman; font-size: xx-small;"><span style="font-family: Times New Roman; font-size: xx-small;">O-doping (0.5 and 0.75 mol %) led to the formation of LiFe</span></span><span style="font-family: Times New Roman; font-size: xx-small;"><span style="font-family: Times New Roman; font-size: xx-small;">5</span></span><span style="font-family: Times New Roman; font-size: xx-small;"><span style="font-family: Times New Roman; font-size: xx-small;">O</span></span><span style="font-family: Times New Roman; font-size: xx-small;"><span style="font-family: Times New Roman; font-size: xx-small;">8 </span></span><span style="font-family: Times New Roman; font-size: xx-small;" lang="JA"><span style="font-family: Times New Roman; font-size: xx-small;" lang="JA">together with γ</span></span><span style="font-family: Times New Roman; font-size: xx-small;"><span style="font-family: Times New Roman; font-size: xx-small;">-Fe</span></span><span style="font-family: Times New Roman; font-size: xx-small;"><span style="font-family: Times New Roman; font-size: xx-small;">2</span></span><span style="font-family: Times New Roman; font-size: xx-small;"><span style="font-family: Times New Roman; font-size: xx-small;">O</span></span><span style="font-family: Times New Roman; font-size: xx-small;"><span style="font-family: Times New Roman; font-size: xx-small;">3 </span></span><span style="font-family: Times New Roman; font-size: xx-small;"><span style="font-family: Times New Roman; font-size: xx-small;">phase. However, the heavily Li</span></span><span style="font-family: Times New Roman; font-size: xx-small;"><span style="font-family: Times New Roman; font-size: xx-small;">2</span></span><span style="font-family: Times New Roman; font-size: xx-small;"><span style="font-family: Times New Roman; font-size: xx-small;">O-doped samples consisted entirely of LiFe</span></span><span style="font-family: Times New Roman; font-size: xx-small;"><span style="font-family: Times New Roman; font-size: xx-small;">5</span></span><span style="font-family: Times New Roman; font-size: xx-small;"><span style="font-family: Times New Roman; font-size: xx-small;">O</span></span><span style="font-family: Times New Roman; font-size: xx-small;"><span style="font-family: Times New Roman; font-size: xx-small;">8</span></span><span style="font-family: Times New Roman; font-size: xx-small;"><span style="font-family: Times New Roman; font-size: xx-small;">. The S</span></span><span style="font-family: Times New Roman; font-size: xx-small;"><span style="font-family: Times New Roman; font-size: xx-small;">BET </span></span><span style="font-family: Times New Roman; font-size: xx-small;"><span style="font-family: Times New Roman; font-size: xx-small;">of pure system prepared from ferric and chromic sulphates measured higher S</span></span><span style="font-family: Times New Roman; font-size: xx-small;"><span style="font-family: Times New Roman; font-size: xx-small;">BET </span></span><span style="font-family: Times New Roman; font-size: xx-small;"><span style="font-family: Times New Roman; font-size: xx-small;">values as compared to those prepared from mixed nitrates, whereas K</span></span><span style="font-family: Times New Roman; font-size: xx-small;"><span style="font-family: Times New Roman; font-size: xx-small;">2</span></span><span style="font-family: Times New Roman; font-size: xx-small;"><span style="font-family: Times New Roman; font-size: xx-small;">O-doping decreased the S</span></span><span style="font-family: Times New Roman; font-size: xx-small;"><span style="font-family: Times New Roman; font-size: xx-small;">BET</span></span><span style="font-family: Times New Roman; font-size: xx-small;"><span style="font-family: Times New Roman; font-size: xx-small;">. On the other hand, Li</span></span><span style="font-family: Times New Roman; font-size: xx-small;"><span style="font-family: Times New Roman; font-size: xx-small;">2</span></span><span style="font-family: Times New Roman; font-size: xx-small;"><span style="font-family: Times New Roman; font-size: xx-small;">O-doping exerted a measurable increase in the S</span></span><span style="font-family: Times New Roman; font-size: xx-small;"><span style="font-family: Times New Roman; font-size: xx-small;">BET</span></span><span style="font-family: Times New Roman; font-size: xx-small;"><span style="font-family: Times New Roman; font-size: xx-small;">. The increase was however, more pronounced in case of the system prepared by using mixed sulphate solutions. The catalytic activity was higher in case of the catalysts prepared by using mixed nitrates as compared to the catalysts prepared by using mixed sulphate solutions. The doping process led to a progressive significant increase in the catalytic activity. The increase was, however, much more pronounced in case of the catalysts prepared from the mixed sulphates. The maximum increase in the k</span></span><span style="font-family: Times New Roman; font-size: xx-small;"><span style="font-family: Times New Roman; font-size: xx-small;">200°C </span></span><span style="font-family: Times New Roman; font-size: xx-small;"><span style="font-family: Times New Roman; font-size: xx-small;">value due to doping with 1.5 mol % K</span></span><span style="font-family: Times New Roman; font-size: xx-small;"><span style="font-family: Times New Roman; font-size: xx-small;">2</span></span><span style="font-family: Times New Roman; font-size: xx-small;"><span style="font-family: Times New Roman; font-size: xx-small;">O attained 30.8% and 285% for the solids prepared from mixed nitrates and mixed sulphates, respectively. These values measured 27% and 241% in case of the catalysts prepared by using mixed nitrate and mixed sulphate solutions, respectively. The doping process did not affect the mechanism of the catalyzed reaction but increased the concentrations of active sites involved in catalytic reaction without changing their energetic nature.</span></span>
nanocrystalline,Fe2O3-Cr2O3,Doping and Catalytic behavior
https://ejchem.journals.ekb.eg/article_1203.html
https://ejchem.journals.ekb.eg/article_1203_2086ad4b8734edc7b851430687ff8c95.pdf
National Information and Documentation Centre (NIDOC), Academy of Scientific Research and Technology, ASRT
Egyptian Journal of Chemistry
0449-2285
2357-0245
53
1
2010
03
02
Comparative Study on Synthesis and Characterization of Ceria Based Composite Oxides Containing Manganese Nano-Particles
61
76
EN
10.21608/ejchem.2010.1204
<span style="font-size: xx-small;">Mn/Ce nano-composite oxides containing different amounts of manganese (5, 9, 17, 23, 29, 34 wt% as MnO</span><span style="font-size: xx-small;">2</span><span style="font-size: xx-small;">) were prepared by impregnation method at various calcination temperatures. Effect of both thermal treatment and loading on the structural, surface and microstructure properties of the as prepared nano-composites was determined. The combined effect of manganese oxide and ceria, at different concentrations, strongly influences the previous properties of the nano-composite oxides, by dispersing the MnO</span><span style="font-size: xx-small;">2 </span><span style="font-size: xx-small;">phase and promoting the efficiency of the Ce</span><span style="font-size: xx-small;">4+</span><span style="font-size: xx-small;">- Ce</span><span style="font-size: xx-small;">3+ </span><span style="font-size: xx-small;">and Mn</span><span style="font-size: xx-small;">4+ </span><span style="font-size: xx-small;">- Mn</span><span style="font-size: xx-small;">3+ </span><span style="font-size: xx-small;">redox couples. </span>
The thermal treatment and loading influenced the interaction between manganese and CeO
<span style="font-size: xx-small;">2 </span><span style="font-size: xx-small;">evidently. The incorporation of Mn ions into CeO</span><span style="font-size: xx-small;">2 </span><span style="font-size: xx-small;">crystal lattice resulted in weaker interaction between manganese and ceria on composite surface. Manganese loading at 400</span><span style="font-size: xx-small;">o</span><span style="font-size: xx-small;">C led to a slight increase in the ceria crystallite size which decreased by increasing the calcination temperature from 400 to 600</span><span style="font-size: xx-small;">o</span><span style="font-size: xx-small;">C. The sintering activation energy of ceria was evaluated to be 12kJ/mol for the MnO</span><span style="font-size: xx-small;">2</span><span style="font-size: xx-small;">/CeO</span><span style="font-size: xx-small;">2 </span><span style="font-size: xx-small;">nano-composite. </span>
XRD,TEM,SBET and MnO2/CeO2 nano-composite
https://ejchem.journals.ekb.eg/article_1204.html
https://ejchem.journals.ekb.eg/article_1204_c5bae39d27114f0296abad59c4cc4d9e.pdf
National Information and Documentation Centre (NIDOC), Academy of Scientific Research and Technology, ASRT
Egyptian Journal of Chemistry
0449-2285
2357-0245
53
1
2010
03
02
Removal of Lead from Aqueous Solutions by Xerogel Film Supported on Activated Carbon and Silica
77
84
EN
Marwa
A
Sherief
0000-0003-1159-0563
National Research Centre
gohamora@yahoo.com
adly
A
Hanna
0000-0001-9589-9597
National Research Centre
a_hanna2006@yahoo.com
Eglal.
R.
Souaya
National Research Centre
marwa-nrc@hotmail.co.uk
Alaa
S
Abdelmoaty
National Research Centre
samir71270@yahoo.com
10.21608/ejchem.2010.1205
CARBON xerogel (X), a kind of novel carbon material with low-density and continuous nano-porous structure that can be controlled and tailored on nanometer scale, has been prepared through the sol <span style="font-family: Times New Roman; font-size: xx-small;"><span style="font-family: Times New Roman; font-size: xx-small;">–</span></span><span style="font-family: Times New Roman; font-size: xx-small;"><span style="font-family: Times New Roman; font-size: xx-small;">gel polycondensation of resorcinol (R) with formaldehyde (F) followed by drying at ambient pressure and carbonization in inert atmosphere. </span></span><span style="color: #231f20; font-family: Times New Roman; font-size: xx-small;"><span style="color: #231f20; font-family: Times New Roman; font-size: xx-small;"><span style="color: #231f20; font-family: Times New Roman; font-size: xx-small;">Batch adsorption experiments were performed to find out the effective lead removal at different metal ion concentrations</span></span></span><span style="font-family: Times New Roman; font-size: xx-small;"><span style="font-family: Times New Roman; font-size: xx-small;">. </span></span><span style="color: #231f20; font-family: Times New Roman; font-size: xx-small;"><span style="color: #231f20; font-family: Times New Roman; font-size: xx-small;"><span style="color: #231f20; font-family: Times New Roman; font-size: xx-small;">Removal of lead from aqueous solutions by adsorption onto </span></span></span><span style="font-family: Times New Roman; font-size: xx-small;"><span style="font-family: Times New Roman; font-size: xx-small;">xerogel film supported on activated carbon and silica has been performed</span></span><span style="color: #231f20; font-family: Times New Roman; font-size: xx-small;"><span style="color: #231f20; font-family: Times New Roman; font-size: xx-small;"><span style="color: #231f20; font-family: Times New Roman; font-size: xx-small;">. </span></span></span><span style="font-family: Times New Roman; font-size: xx-small;"><span style="font-family: Times New Roman; font-size: xx-small;">The removal of Pb ions from aqueous solutions was studied by batch method. The effects of initial metal concentrations, initial pH, contact time and the quantity of adsorbents were investigated. It was found that carbon xerogel supported on activated carbon exhibited the best adsorption potential for removal of lead ions from solutions.</span></span>
Lead removal,Xerogel,Activated carbon,Silica and Coating
https://ejchem.journals.ekb.eg/article_1205.html
https://ejchem.journals.ekb.eg/article_1205_d8f327ffee3301b0a38bcda03101ce01.pdf
National Information and Documentation Centre (NIDOC), Academy of Scientific Research and Technology, ASRT
Egyptian Journal of Chemistry
0449-2285
2357-0245
53
1
2010
03
02
Electrical and Structural Properties of Nickel Oxide - Containing Phosphate Glasses
85
99
EN
10.21608/ejchem.2010.1206
PHOSPHATE glasses containing 0.05-7.5g NiO/100 glass were <span style="color: #ffffff; font-family: Times New Roman; font-size: xx-small;" lang="JA"><span style="color: #ffffff; font-family: Times New Roman; font-size: xx-small;" lang="JA"><span style="color: #ffffff; font-family: Times New Roman; font-size: xx-small;" lang="JA">…. </span></span></span><span style="font-family: Times New Roman; font-size: xx-small;"><span style="font-family: Times New Roman; font-size: xx-small;">prepared using sodium di-hydrogen phosphate. The prepared glasse were investigated using IR, a.c. conductivity, dielectric constant (</span></span><span style="font-family: Times New Roman; font-size: xx-small;" lang="JA"><span style="font-family: Times New Roman; font-size: xx-small;" lang="JA">ε</span></span><span style="font-family: Times New Roman; font-size: xx-small;"><span style="font-family: Times New Roman; font-size: xx-small;">`) and the dielectric loss (</span></span><span style="font-family: Times New Roman; font-size: xx-small;" lang="JA"><span style="font-family: Times New Roman; font-size: xx-small;" lang="JA">ε</span></span><span style="font-family: Times New Roman; font-size: xx-small;"><span style="font-family: Times New Roman; font-size: xx-small;">``). IR spectra revealed that the Ni</span></span><span style="font-family: Times New Roman; font-size: xx-small;"><span style="font-family: Times New Roman; font-size: xx-small;">2+ </span></span><span style="font-family: Times New Roman; font-size: xx-small;"><span style="font-family: Times New Roman; font-size: xx-small;">ions are located near P=O. Addition of Na</span></span><span style="font-family: Times New Roman; font-size: xx-small;"><span style="font-family: Times New Roman; font-size: xx-small;">2</span></span><span style="font-family: Times New Roman; font-size: xx-small;"><span style="font-family: Times New Roman; font-size: xx-small;">O causes a breakdown of the ring type with the formation of more non-bridging oxygens and depolymerization of the network. The conductivity of Ni-containing glasses is more than that of Ni-free phosphate glass, and attain maximum value for glass containing 0.25 g NiO per 100g glass The </span></span><span style="font-family: Times New Roman; font-size: xx-small;" lang="JA"><span style="font-family: Times New Roman; font-size: xx-small;" lang="JA">relation between log σ and reciprocal of the temperature suggests that, </span></span><span style="font-family: Times New Roman; font-size: xx-small;"><span style="font-family: Times New Roman; font-size: xx-small;">the mechanism predominating in the high temperature region is ionic in nature, while it is electronic in origin in the low temperature region. Introducing NiO extends electronic conduction through hopping mechanism to the high temperature region particularly at high frequency. The dielectric constant</span></span>′ and the dielectric loss ε <span style="font-family: Times New Roman; font-size: xx-small;"><span style="font-family: Times New Roman; font-size: xx-small;">`` increase with increasing temperature, while a decrease in</span></span>′ with <span style="font-family: Times New Roman; font-size: xx-small;"><span style="font-family: Times New Roman; font-size: xx-small;">increasing frequency was observed.</span></span>
Phosphate glasses,Nickel oxide-containing glasses,electrical conductivity,Dielectric constant and Dielectric loss
https://ejchem.journals.ekb.eg/article_1206.html
https://ejchem.journals.ekb.eg/article_1206_ef27f11d56f569699632afd5ee83597b.pdf
National Information and Documentation Centre (NIDOC), Academy of Scientific Research and Technology, ASRT
Egyptian Journal of Chemistry
0449-2285
2357-0245
53
1
2010
03
02
Spectrophotometric and Potentiometric Methods for the Determination of Cefprozil, Dropropizine and Tizanidine Hydrochloride in Pharmaceutical Preparations
101
115
EN
10.21608/ejchem.2010.1207
<span style="font-size: xx-small;">TWO SIMPLE, accurate spectrophotometric and potentiometric m methods were developed for the determination of cefprozil, dropropizine and tizanidine hydrochloride in their pharmaceutical preparations. The spectrophotometric method is based on the selective oxidation of cefprozil or tizanidine with N-bromosuccinimide in an alkaline medium to give an intense yellow product with a maximum absorption at 396 or 384 nm, respectively. The reaction conditions were studied and optimized. The reaction obeyed Beer's law over the concentration range 5-40 and 10-80 g ml</span><span style="font-size: xx-small;">-1 </span><span style="font-size: xx-small;">for cefprozil and tizanidine hydrochloride, respectively. The potentiometric method involves the direct titration of cefprozil and dropropizine with N-bromosuccinimide in sulphuric acid medium and the end point is determined potentiometrically using platinum electrode. Cefprozil and dropropizine can be determined quantitatively in the concentration range of 0.13-1.30 and 0.118-1.180 mg with recovery values of 98.46-100.77 and 99.58-100.85% and relative standard deviations 0.39-0.54 and 0.52-0.87% for cefprozil and dropropizine, respectively. The proposed methods are applied for the determination of these drugs in pure forms and in pharmaceutical preparations. </span>
Cefprozil,Dropropizine,Tizanidine hydrochloride,N-Bromosuccinimide,Spectrophotometry and Potentiometry
https://ejchem.journals.ekb.eg/article_1207.html
https://ejchem.journals.ekb.eg/article_1207_ab12586f661fc6852bcd7184fb0fe301.pdf
National Information and Documentation Centre (NIDOC), Academy of Scientific Research and Technology, ASRT
Egyptian Journal of Chemistry
0449-2285
2357-0245
53
1
2010
03
02
Corrosion Study of Glaze-Ceramics Doped Cement-Kiln-Dust Soaked in Concentrated HCl
117
135
EN
10.21608/ejchem.2010.1208
<span style="font-size: xx-small;">NEW glaze-ceramics formulated from industrial waste have been ....... prepared. The method consists of introducing cement-kiln-dust (CKD) in the industrial glaze-ceramics with various ratios (10-50%) together with the addition of 10gm boric acid. The chemical durability of the prepared composite cement-dust-glaze-ceramics (CDGC) is investigated using high concentrations of (2,5 & 8N) HCl acid solutions. CDGC are vitrified by melting for four hours at 1400</span><span style="font-size: xx-small;">o</span><span style="font-size: xx-small;">C ± 250</span><span style="font-size: xx-small;">o</span><span style="font-size: xx-small;">C depending on the amount of CKD introduced. Specifically, the experimental results indicate that the introduction of CKD in industrial glaze decreases durability. At high HCl concentrations, the durabilities of the prepared glaze-ceramics are observed to decrease with increasing the percentage of (CKD) until certain limit and almost constancy. The corrosion results are explained according to the ion exchange mechanism and formation or dissociation of the modified depleted layer. </span>
Some hollow and jogged areas are observed by SEM which might be interpreted as evidence of local corrosion phenomena. In addition, the pH values of the leachant solutions are measured. The comparison of hardness for the optimum glaze-ceramic and glaze-ceramic derivatives prepared in this study indicates a degradation % in their chemical and physical properties depending on the amount% of CKD introduced. It is observed that the degradation not only depends on the amount of CKD introduced, but also on the strength of the leaching HCl acid solution. Also, the results show that, the prepared glazes have a surface hardness values ranged from 5.5 to 2.5 in the Mohs scale.
CKD waste,New glaze-ceramics,Corrosion and Hardness
https://ejchem.journals.ekb.eg/article_1208.html
https://ejchem.journals.ekb.eg/article_1208_0b5766c24569822a287e0ed12b307e12.pdf
National Information and Documentation Centre (NIDOC), Academy of Scientific Research and Technology, ASRT
Egyptian Journal of Chemistry
0449-2285
2357-0245
53
1
2010
03
02
Synthesis, Spectroscopic Characterization, Thermal Investigation and Antimicrobial Activity of S, O and N-Donor Heterocyclic Schiff Base Ligands and their Co(II), Cd(II), Hg(II), Fe(III) and UO2(II) Metal Complexes
137
162
EN
10.21608/ejchem.2010.1209
<span style="font-size: small;">THE POLYDENTATE ligands 2,5-N,N-bis (dimethyl-1- ……phenyl-4-pyrazoline-5-one) furanidine; 2,5-N,N-bis (pyridine) furanidine and 2,5-N,N-bis (2-thiophenol) furanidine (L</span><span style="font-size: xx-small;">1 </span><span style="font-size: small;">– L</span><span style="font-size: xx-small;">3</span><span style="font-size: small;">), have been prepared and identified. The chemical behavior of these ligands towards some metal cations such as Co(II) Cd(II), Hg(II), Fe(III) and UO</span><span style="font-size: xx-small;">2</span><span style="font-size: small;">(II) was studied. The isolated complexes are characterized using analytical data, IR, </span><span style="font-size: xx-small;">1</span><span style="font-size: small;">H-NMR, UV-visible, mass spectroscopy, magnetic susceptibility, thermal analysis and molar conductance measurements. Bonding of the ligands with the metal ions is deduced from IR spectra and the presence of the mononuclear complexes are inferred from the mass spectral study. An octahedral structure is proposed for the prepared metal complexes and some ligand field parameters (D</span><span style="font-size: xx-small;">q</span><span style="font-size: small;">, B, and β) in addition to LFSE were calculated from electronic spectral data. All synthesized compounds were screened for their antimicrobial activity against gram positive and gram negative bacteria and fungi. The biological evalution study showed high to moderate bacterial activity compared with the ligands, their metal complexes and known antibiotics data. </span>
Heterocyclic ligands,Metal complexes,Thermal studies and Antimicrobial activity
https://ejchem.journals.ekb.eg/article_1209.html
https://ejchem.journals.ekb.eg/article_1209_f05990ef3a45748258c1002976334acd.pdf
National Information and Documentation Centre (NIDOC), Academy of Scientific Research and Technology, ASRT
Egyptian Journal of Chemistry
0449-2285
2357-0245
53
1
2010
03
02
Density and Speed of Sound of Sodium Nitroprusside with Aqueous Alcohols
163
176
EN
10.21608/ejchem.2010.1210
<span style="font-size: xx-small;">STUDIES on apparent molar volumes for the solutions of sodium sodi nitroprusside in aqueous solutions of methanol, ethanol and propanol in the temperature range 298.15 to 313K at 5K intervals have been determined from the density measurements of the solutions. Speed of sound of solutions of sodium nitroprusside in aqueous solutions of alcohols has also been experimentally determined at 303.15K.Molar isentropic compressibilities and apparent molar isentropic compressibilities have been calculated from the speed of sound data. These results have been used to calculate the following partial molar quantities : </span>
, , V0 E 0s K
Various acoustic parameters and solvation number have been evaluated for sodium nitroprusside in different aqueous solutions of alcohols. The results are discussed in the light of solute- solvent and solute –solute interactions.
water,Alcohols,Sodium nitroprusside,Apparent molar volume,density,Solvation number,ultrasonic velocity,Molar isentropic compressibilities and Apparent molar isentropic compressibilities
https://ejchem.journals.ekb.eg/article_1210.html
https://ejchem.journals.ekb.eg/article_1210_d741902aab3379edf139994b73fb1459.pdf