لقد حضر في هذا البحث عدد من المعقدات الجديدة لبعض ايونات العناصر الانتقالية وهي كل من Fe(II) , Fe(III) , Co(II) , Ni(II) , Cu(II) و Zn(II) مع الكاشف العضوي -4 ( -2 بريديل آزو ) ريزورسينول المعروف ب (PAR) . حيث تم التحضير بعد تثبيت الظروف المثلى من دالة حامضية وتركيز مولاري بوساطة أطياف الاشعة فوق البنفسجية – المرئية لمحاليل مزج الايونات الفلزية مع محاليل الكاشف العضوي اعلاه ولمدى واسع من الدالة الحامضية والتركيز المولارية الخاضعة لقانون لامبرت – بير وقد تباينت ظروف التحضير بتابين الايونات الفلزية المدروسة . إذ تم تحضير ثلاثة معقدات لكل من آيوني النيكل (II) ومعقدين لآيون الكوبلت (II) ومعقدين لكل من الحديد (II) و (III) والخارصين (II) بأختلاف ظروف التحضير . كما تم التعرف على تراكيب هذه المعقدات عن طريق ايجاد النسبة المولية للفلز : الليكاند من خلال الدراسات الطيفية لمحاليل معقدات الفلزات المذكورة آنفا وذلك بأستخدام طريقة النسب المولية وقد تراوحت هذه النسب ما بين 1:1 أو 2:1 . وبعد تنقية المركبات الصلبة الناتجة درست بوساطة أطياف الاشعة فوق البنفسجية – المرئية حيث أظهرت أطياف محاليلها في الميثانول ازاحة حمراء لوحظت في منطقة الطيف المرئي لجميع المعقدات . كما درست بوساطة اطياف الاشعة تحت الحمراء إذ سجلت تغييرات واضحة لاطياف المعقدات نسبة الى طيف الليكاند الحر . ولوحظ ظهور حزم جديدة لم تكن موجودة في طيف الليكاند تدل على الاتباط الثنائي او الثلاثي السن لليكاند بالآيون الفلزي . إذ أنه من المتوقع ان تكون مواقع الارتباط لليكاند من خلال اوكسجين مجموعة الهيدروكسيل اورثو لحلقة الريزورسينول ( بعد ان تفقد بروتونها) ونيتروجين مجموعة الآزو القريبة من حلقة الريزوسينول ونيتروجين حلقة البريدين إذ تتكون حلقتان خماسيتان مستقرتان مما تعطيان استقرارا عاليا لهذه المعقدات . كما تم اجراء التحاليل الدقيقة لعناصر (N , H , C) لهذه المعقدات وتم تعيين النسب المئوية للأيونات الفلزية باستخدام مطيافية الامتصاص الذري اللهبي كما تم تعيين نسبة عنصر الكبريت وآيون الكلوريد بأستخدام طرق تحليلية مختلفة . وقد أظهرت نتائج هذه التحاليل جميعاً تقاربا للنسب المئوية المستحصلة مع النسب النظرية المحسوبة للصيغ التركيبية المقترحة لهذه المعقدات. أما دراسة التوصيلة الكهربائية لمحاليل المعقدات المحضرة في مذيبي الميثانول وثنائي ميثل فورم امايد فقد أظهرت ان المعقدات لا تمتلك صفات آيونية . كذلك فقد شملت الدراسة أيضا اجراء التحاليل الحرارية TGو DTG لليكاند الـ PAR وللمعقدات المحضرة جميعاً . وقد أثبتت هذه التحاليل وجود جزيئة ماء تبلور واحدة في جميع المعقدات ومن النسب المئوية للفقدان في الوزن التي سجلتها المنحنيات الحرارية ومقارنتها مع النسب المحسوبة نظريا فقد تم التوصل الى ان الخط العام للتحلل الحراري تضمن تكون جذور حرة للريزورسينول والبريدين مع تحرر غاز النيتروجين أثناء عملية التحلل . اما المواد الصلبة المتبقية من نواتج فهي أما العناصر او اكاسيد العناصر لكل معقد . واخيرا فقد دعمت النتائج أعلاه باجراء تحاليل طيف الكتلة الذي أثبت بما لايقبل الشك الصيغ الجزيئية المقترحة المحضرة . وتعتبر الدراستان الاخيرتان ( التحلل الحرارية وأطياف الكتلة ) الاولى من نوعها التي تجرى على ليكاند الـ PAR ومعقداتها الفلزية .
In this paper, two elements of the multi-input multi-output (MIMO) antenna had been used to study the five (3.1-3.55GHz and 3.7-4.2GHz), (3.4-4.7 GHz), (3.4-3.8GHz) and (3.6-4.2GHz) 5G bands of smartphone applications that is to be introduced to the respective US, Korea, (Europe and China) and Japan markets. With a proposed dimension of 26 × 46 × 0.8 mm3, the medium-structured and small-sized MIMO antenna was not only found to have demonstrated a high degree of isolation and efficiency, it had also exhibited a lower level of envelope correlation coefficient and return loss, which are well-suited for the 5G bands application. From the fabrication of an inexpensive FR4 substrate with a 0.8 mm thickness level, a loss tang
... Show MoreTow simple, rapid and sensitive spectrophotometric methods for the determination of mesalazine in pharmaceutical preparations have been carried out. The proposed methods depend on oxidative coupling reaction of mesalazine with m-aminophenol in the existence of N-bromosuccinamide in alkaline medium (method A) and 2,6-dihydroxybenzoic acid in the existence of sodium metaperiodate in basic medium (method B) to produce colored products , show highest absorptions at 640 (nm) and 515 (nm), alternately. Beer’s law was consistent in concentrations extent of 1.25-30 and 0.5-12.5 (µg.mL-1) with molar absorptivity of 0.36×104 and 0.77×104 L.mol-1.cm<
... Show MoreThe current study deals with the performance of constructed wetland (CW) incorporating a microbial fuel cell (MFC) for wastewater treatment and electricity generation. The whole unit is referred to as CW-MFC. This technique involves two treatments; the first is an aerobic treatment which occurs in the upper layer of the system (cathode section) and the second is anaerobic biological treatment in the lower layer of the system (anode section). Two types of electrode material were tested; stainless steel and graphite. Three configurations for electrodes arrangement CW-MFC were used. In the first unit of CW-MFC, the anode was graphite plate (GPa) and cathode was also graphite plate (GPc), in the second CW-MFC unit, the anode was stainless st
... Show MoreAbstract
Anaerobic digestion process of organic materials is biochemical decomposition process done by two types of digestion bacteria in the absence of oxygen resulting in the biogas production, which is produced as a waste product of digestion. The first type of bacteria is known as acidogenic which converts organic waste to fatty acids. The second type of bacteria is called methane creators or methanogenic which transforms the fatty acids to biogas (CH4 and CO2). The considerable amounts of biodegradable constitutes such as carbohydrates, lipids and proteins present in the microalgae biomass make it a suitable substrate for the anaerobic digestion or even c
... Show More
In this work, a test room was built in Baghdad city, with (2*1.5*1.5) m3 in dimensions, while the solar chimneys (SC) were designed with aspect ratio (ar) bigger than 12. Test room was supplied by many solar collectors; vertical single side of air pass with ar equals 25, and tilted 45o double side of air passes with ar equals 50 for each pass, both collectors consist of flat thermal energy storage box collector (TESB) that covered by transparent clear acrylic sheet, third type of collector is array of evacuated tubular collectors with thermosyphon in 45o instelled in the bottom of TESB of vertical SC. The TESB was
... Show MoreThis study synthesized zeolite 4A, and hierarchical composite structure consisting of zeolite 4A- carbon were successfully prepared. Hydrothermal method was used to grow a layer of zeolite 4A over porous carbon surfaces to enhance mass transfer and increase surface area of zeolite. The products then were used to remove radioactive cesium137Cs from liquid wastewater. Iraqi dates leaves midribs (DM) were used as locally available agricultural waste to prepare low- cost porous carbon, using carbonization method in tubular furnace at 900C for two hours. Hierarchical porous structures including zeolite are prepared by mechanically activating the carbon surface via Ultrasonicating nanoparticles suspension of ground zeolite type 4A.F
... Show MoreThe research aims to reveal the methods of visual intertextuality used in the websites of the oriented satellite channel which is Arabic-speaking when addressing normalization with Israel. It also indicates the sources and types of intertextual images, the methodological and semiotic mechanisms for analyzing the intertextuality of news images used on the website of Alhurra satellite channel for the period from 1/6 - 30/8/2022, which included (94) images. The researcher analyzed (37) images with intertextual dimensions, excluding (57) images, which did not carry connotations connected with the inputs and objectives of the research.
The research reach
... Show MoreThis research was carried out to study the effect of plants on the wetted area for two soil types in Iraq and predict an equation to determine the wetted radius and depth for two different soil types cultivated with different types of plants, the wetting patterns for the soils were predicted at every thirty minute for a total irrigation time equal to 3 hr. Five defferent discharges of emitter and five initial volumetric soil moisture contents were used ranged between field capacity and wilting point were utilized to simulate the wetting patterns. The simulation of the water flow from a single point emitter was completed by utilized HYDRUS-2D/3D software, version 2.05. Two methods were used in developing equations to predict the domains o
... Show MoreAbstract
This work involves the manufacturing of MAX phase materials include V2AlC and Cr2AlC using powder metallurgy as a new class of materials which characterized by regular crystals in lattice. Corrosion behavior of these materials was investigated by Potentiostat to estimate corrosion resistance and compared with the most resistant material represented by SS 316L. The experiments were carried out in 0.01N of NaOH solution at four temperatures in the range of 30–60oC. Polarization resistance values which calculated by Stern-Geary equation indicated that the MAX phase materials more resistant than SS 316L. Also cyclic polarization tests confirme
... Show MoreThis growing interest of the international scientific specialized commissions is due to the role that the audit committee can play, as one of companies’ governance tools, to increase the accuracy and transparency of the financial information disclosed by the companies, through its oversight role on the process of preparing financial reports, its supervision on the internal audit function within the companies, and supporting its independency, as well as coordinating the efforts between the internal control unites and the external auditor represented by the (Board of Supreme Audit) to clear the observations and irregularities in order to reduce the fraud cases.
This research was built on an applied sample of audit committee works
... Show More