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نوع الوثيقة |
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مقال في مجلة دورية |
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عنوان الوثيقة |
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تأثير استبدال الألمونيوم على التركيب الكيميائي والخصائص المغناطيسية لبودرة المنجنيز والزنك متناهية الصغر والمعدة بطريقة الحرق الذاتي للجيل والسائل Influence of Al-substitution on structural, electrical and magnetic properties of Mn–Zn ferrites nanopowders prepared via the sol–gel auto combustion method |
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الموضوع |
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علوم البيئة |
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لغة الوثيقة |
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الانجليزية |
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المستخلص |
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A series of nano-sized Al-substituted manganese zinc ferrites, Mn0.8Zn0.2Fe2xAlxO4 (x = 0.01.0), with a
cubic spinel crystal structure were prepared through the citrate sol-gel auto-combustion method. Thermogravimetric
measurements revealed that the optimum calcination temperature for complete formation
of ferrites is 300 C. At higher calcination temperatures X-ray diffraction indicated the presence of
Fe2O3 and Mn2O3 secondary phases, attributed to the ferrites decomposition. The average crystallite size,
calculated using the Debye–Scherrer equation, lies in the range 5–38 nm. The gradual decrease in lattice
parameter with increasing Al-content can be attributed to the smaller ionic radii of the Al3+ ion. The TEM
image showed large agglomerates of strongly connected cubic aggregates. FT-IR spectra exhibited two
prominent absorption bands, m1 and m2, characteristic for the spinel structure. VSM measurements indicated
a gradual decrease in the saturation magnetization with increasing Al-content, until it vanished at
x = 0.8, followed by a slight increase. The reduction in coercivity with increasing Al-content can be
ascribed to the effect of magneto-crystalline anisotropy. Based on XRD, FT-IR and VSM studies, an appropriate
cation distribution for the present investigated system was suggested. The temperature dependence
of the AC-conductivity as a function of the applied frequency showed semiconducting behavior
with a transformation in the conduction mechanism from the ferrimagnetic to the paramagnetic state
for ferrites with x 6 0.4. |
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ردمد |
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0277-5387 |
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اسم الدورية |
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PERGAMON-ELSEVIER SCIENCE LTD, THE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, ENGLAND |
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المجلد |
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57 |
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العدد |
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1 |
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سنة النشر |
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1434 هـ
2013 م |
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نوع المقالة |
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مقالة علمية |
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تاريخ الاضافة على الموقع |
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Tuesday, June 4, 2013 |
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الباحثون
| M.A. Gabal | Gabal, M.A. | باحث | | mgabalabdonada@yahoo.com |
| A.M. Abdel-Daiem | Abdel-Daiem, A.M. | باحث | | |
| Y.M. Al Angari | Al Angari, Y.M. | باحث | | |
| I.M. Ismail | Ismail, I.M. | باحث | | |
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الملفات
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35613.pdf
| pdf | Influence of Al-substitution on structural, electrical and magnetic properties
of Mn–Zn ferrites nanopowders prepared via the sol–gel auto-combustion
method |
|