عرف العرب ، منذ القدم ، الأحجار الكريمة وعنوا بإقتناء أنواعا عديدة منها ، حيث كانت من أهم واردات سكان بلاد وادي الرافدين من السومريين والبابليين ثم الآشوريين ، كما عرفها المصريون القدماء وغيرهم من الشعوب القديمة ، فوجدت في قبورهم ومدافنهم وخزائن كنوزهم، مثل الياقوت الأحمر واللازورد واللؤلؤ . بالإضافة إلى ذلك فقد كان معدني الذهب والفضة من المعادن الوفيرة في هذه البلاد ، ولها الأولوية في صناعة الحلي.

     In the present work, a kinetic study was performed to the extraction of phosphate from Iraqi Akashat phosphate ore using organic acid. Leaching was studied using lactic acid for the separation of calcareous materials (mainly calcite). Reaction conditions were 2% by weight acid concentration and 5ml/gm of acid volume to ore weight ratio. Reaction time was taken in the range 2 to 30 minutes (step 2 minutes) to determine the reaction rate constant k based on the change in calcite concentration. To determine value of activation energy when reaction temperature is varied from 25 to 65 , another investigation was accomplished. Through the kinetic data, it was found that selective leaching was controlled by

The purpose of this interview study was to explore teachers’ perceptions of Response to Intervention (RtI) implementation in their school. Particularly, the study explored teachers’ knowledge of RtI, teachers’ perceptions of RtI their intervention/instruction in school, and teachers’ suggestions of RtI implementation in their school. The study design was a qualitative interview in nature and data were collected from face-to-face interviews with four teachers in one school. The findings revealed that RtI means to identify students’ problems; the positive teachers’ perceptions of their implementation included: (a) students who demonstrate progress through RtI are those who receive private education services, (b) progress monito

In this paper we present a method to analyze five types with fifteen wavelet families for eighteen different EMG signals. A comparison study is also given to show performance of various families after modifying the results with back propagation Neural Network. This is actually will help the researchers with the first step of EMG analysis. Huge sets of results (more than 100 sets) are proposed and then classified to be discussed and reach the final.

Statistical studies are reported in this article for an active galactic nuclei sample of different type of active galaxies Seyferts 1, Seyferts 2, and Quasars. These sources have been selected from a Catalogue for bright X-ray galaxies. The name of this index is ROSAT Bright Source Catalogue (RBSC) and the NRAO VLA Sky Survey (NVSS). In this research, multi-wavelength observational bands Radio at 1.4 GHz, Optical at 4400 A⁰, and X-ray at energy 0.1-2.4 KeV have been adopted in this study. The behavior of flux density ratios has been studied ,  with respect to the absolute magnitude . Furthermore, the Seyfert1 and Seyfert 2 objects are combined in one group and the QSOs are collectest in another group. Also, it has been fo

أظهرت نتائج تقدير التركيب الكيميائي لمعزول بروتين بقول العدس المنبت التي تم الحصول عليها من الأسواق المحلية في محافظة بغداد وذلك باستخدام الاستخلاص القلوي عند الرقم الهيدروجيني 9.5 PH ثم الترسيب عند نقطة التعادل الكهربائي 4.5 PH،كانت نسبة البروتين، الرطوبة، الرماد، الألياف، الدهن والكربوهيدرات (71.58، 6.44، 2.58، 1.09، 0.25، 8.66) % على التوالي، وبينت نتائج تقدير المعادن في المعزول البروتيني لكل من الكالسيوم والفسفور والحد

This research has been written as a fullfillment of the researchers
desire of joining the qurannic convoy servos each one from his own place and
this own field of specialization . she has found that the holly quraan is a
parctical field for theories and rules of old and modren phonetic studies also
she has becom a ware of the fact that the quraanic Important –making has
various aspects that neither can be a ware of nor can be vanished by the
courses of ages for science can flourish and reach tops to the extent they
don’t accept any new addition theories can be studied and given laws at last
except the quannice important – making which is new and discovered at
deferent times and places in spite of the shor

This study investigates the surgical and thermal effects on oral soft tissues produced by CO2 laser emitting at 10.6 micrometers with three different fluences 490.79, 1226.99 and 1840.4 J/cm2. These effects are specifically; incision depth, incision width and the tissue damage width and depth. The results showed that increasing the fluence and /or the number of beam passes increase the average depths of ablation. Moreover, increasing the fluence and the number of beam passes increase the adjacent tissue damage in width and depth. Surgeons using CO2 laser should avoid multiple pulses of the laser beam over the same area, to avoid unintentional tissue damage.