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Effect of formation Methods on Sintering Process of Ceramic Materials: هديل سلمان سعيد
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The current research is concerned with methods of formation and their effect on the sintering process of ceramic materials. The research is divided into a number of chapters. The first chapter addressed the research structure (the research problem, importance, objective, limits, and it also defined the terms used in the research). The second chapter addressed the theoretical framework, where the theoretical framework has been divided into three sections. The first section dealt with methods of formation of ceramic materials including: Plasticizing method 2- semi-dry pressing method 3- dry pressing method 4- extrusion method 5- casting method.
The researcher found that there is a clear difference between the methods through her formation of tables and as it is clear in the research body. As for the second section, it addressed studying the raw ceramic materials that the researcher has classified into: 1- plastic raw materials 2- non-plastic raw materials. In the third section, the researcher addressed types and divisions of sintering: First: sintering in the solid state and its stages. Second: sintering with the presence of an effective liquid. Third: sintering by pressing and hot compression.
The third chapter consists of the research procedures that addressed 1- preparing the raw material. 2- Examination of the raw material through a- chemical analysis b- metal composition c- thermal microscope examination. 3- Preparing the mixtures where four hypotheses have been put and in every hypothesis, the researcher dealt with what results from mixing the materials (Silica, crock, sodium carbonate, and kaolin under various temperatures and pressure). 4- preparing the laboratory models in which the researcher tackled 1- mixing the materials 2- forming the laboratory models 3- drying process 4-burning process 5- determining the general features for the models. The researcher has conducted some experiments to determine the features of the models after the burning process according to the following: Calculating the longitudinal contraction b- water suction c-virtual space. The fourth chapter addressed and discussed the research results. The researcher reached at the results through conducting the laboratory examinations for the samples within tables (4, 5) affixed in the research. The recommendations and suggestions put forth by the researcher to complete the scientific approach for the research are as follows: 1- not to start the research before finding the oven. 2- Conducting examinations using a thermal microscope before burning 3- burning at a slow timing rate to prevent the occurrence of distortions.

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Publication Date
Tue Sep 01 2009
Journal Name
Journal Of Economics And Administrative Sciences
Determine the optimal decision in the process of production planning usingDynamic programming style
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The operation of production planning is a difficult operation and it's required High effect and large time especially it is dynamic activity which it's basic variables change in continuous with the time, for this reason it needs using one of the operation research manner (Dynamic programming) which has a force in the decision making process in the planning and control on the production and its direct affect on the cost of production operation and control on the inventory.

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Publication Date
Wed Aug 01 2018
Journal Name
Journal Of Economics And Administrative Sciences
Comparison Some Estimation Methods Of GM(1,1) Model With Missing Data and Practical Application
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This paper presents a grey model GM(1,1) of the first rank and a variable one and is the basis of the grey system theory , This research dealt  properties of grey model and a set of methods to estimate parameters of the grey model GM(1,1)  is the least square Method (LS) , weighted least square method (WLS), total least square method (TLS) and gradient descent method  (DS). These methods were compared based on two types of standards: Mean square error (MSE), mean absolute percentage error (MAPE), and after comparison using simulation the best method was applied to real data represented by the rate of consumption of the two types of oils a Heavy fuel (HFO) and diesel fuel (D.O) and has been applied several tests to

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Publication Date
Tue Dec 31 2019
Journal Name
Journal Of Economics And Administrative Sciences
The Effect of Disclosure and Transparency Criteria In Saudi Banks on The Financial Ratios Indicators
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The study aimed to measure the effect of applying the disclosure and transparency standards criteria adopted by the Saudi Arabian Monetary Authority on improving performance indicators in the Saudi banking sector, by measuring the extent of the impact of the bank's financial indicators represented by liquidity, profitability and return on assets in Saudi banks by applying the criteria of disclosure and transparency, which is one of the Main principles in the list of governance, which was approved by the Saudi Arabian Monetary Authority. The analytical approach was followed to achieve the goal of the study, as the financial statements of Saudi banks were analyzed during a period of 8-year to test four hypotheses related to measuri

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Publication Date
Wed Jul 01 2020
Journal Name
Iraqi Geological Journal
THE EFFECT OF SOME MATERIALS ON FUNNEL VISCOSITY READING IN WATER BASE MUD
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Publication Date
Fri Jun 28 2019
Journal Name
Journal Of The College Of Education For Women
Creative Formation in the Poetry of Thafer Bin Qasim Al-Haddad (529 A.H) (Creative Ingenuity as Model): خلود هاشم جوحي الوائلي
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Through research and research in the creative composition in the poetry of Zafer-Alhaddad it turned out to be superior in its systems, especially that he chose a linguistic and verbal texture accompanied by a cultural dictionary full of creativity and beauty helped this culture arrangement reflects the poetically wonderful and beautiful custom led to the harmony of colors and bodies painted by the poet brush the creative artist evaluates the metaphorical and metaphorical relations that would explain the poets idea, most of which were inspired by the wonderful spirit of nature, its beautiful landscapes and bright colors, especially that we do not forget the beautiful colors and the aesthetic touch that created a fascinating musical intera

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Publication Date
Sun Feb 24 2019
Journal Name
Iraqi Journal Of Physics
Study the effect of gamma radiation on the some properties of glass and glass-ceramic immobilize nuclear waste
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Vitrifications process one of the important methods to immobilize nuclear waste.  In this research nuclear waste (Strontium Oxides) with molecular weight (5%) was immobilized by vitrification methods in two types of borosilicate glass (c-type) which are glass and glass-ceramics. To investigate the physical, chemical and mechanical properties of glass and glass-ceramic after immobilize nuclear waste these samples irradiated by gamma ray radiation. Co-60 was used as gamma a irradiation with dose rate 0.38 kGy/hr for different period of time. It’s found that gamma radiation affected the glass and glass-ceramic properties. From phase analysis by the x-ray diffraction for glass-ceramic samples proved that at doses 343kGy change the cry

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Publication Date
Sat May 16 2026
Journal Name
Journal Of Baghdad College Of Dentistry
Effect of different acids surface treatments and thermocycling on shear bond strength of composite resin to feldspathic ceramic
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Background: the aim of this study was to evaluate the effect of different surface acids treatments (37%phospjoric acid, 5%hydrofluoric acid, 1.23 acidulated phosphate fluoride) of feldspathic ceramic VITA 3D MASTER , and the effect of thermocycling on shear bond strength using a ceramic repair kit (ivoclar/vivadent). Material and Methods: sixty Nickel-Chromium metal base plates were prepared(9mm diameter,3mm depth) using lost wax technique, 2mm thick layer of ceramic(VITA 3D MASTER) fused to metal plates, all specimens were embedded in acrylic resin blocks except their examined surfaces and divided into 3 main groups 20 specimens each, Grp A: treatment with 37%phosphoric acid for 2 mins, Grp B: etching with 5% hydrofluoric acid for 2mins,

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Publication Date
Wed Jun 01 2011
Journal Name
Journal Of Economics And Administrative Sciences
Methods of using the periodic chart in the case of the missing values of the stable AR model (2)
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In this study, we investigate the behavior of the estimated spectral density function of stationary time series in the case of missing values, which are generated by the second order Autoregressive (AR (2)) model, when the error term for the AR(2) model has many of continuous distributions. The Classical and Lomb periodograms used to study the behavior of the estimated spectral density function by using  the simulation.

 

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Publication Date
Mon Jan 01 2018
Journal Name
Matec Web Of Conferences
Effect of internal curing on performance of self-compacting concrete by using sustainable materials
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This paper is devoted to investigate the effect of internal curing technique on the properties of self-compacting concrete. In this study, self-compacting concrete is produced by using limestone powder as partial replacement by weight of cement with percentage of (5%), sand is partially replaced by volume with saturated fine lightweight aggregate which is thermostone aggregate as internal curing material in three percentages of (5%, 10%, 15%) for self-compacting concrete, and the use of two external curing conditions which are water and air. The experimental work was divided into three parts: in the first part, the workability tests of fresh self-compacting concrete were conducted. The second part included conducting compressive str

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Publication Date
Thu Jun 15 2017
Journal Name
Journal Of Baghdad College Of Dentistry
The Effect of Different Light Cure Systems on Microhardness of Bulk Fill Composite Materials
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Background: The aim of this study was to evaluate the effect of three types of light curing devices QTH, LED and Flashmax on the surface microhardness of three types of bulkfill composite resins; Filtek Bulkfill posterior composite ( 3M), Tetric Evo Ceram ( Ivoclar Vivadent) and Sonicfill composite ( Kerr) Materials and methods: Total number of 90 samples was prepared, 30 samples for each type of bulkfill composite, were divided into three main groups, group A: Filtek posterior bulkfil (3M), group B: Tetric Evo Ceram (Ivoclar Vivadent) and group C: contain Sonicfill composite (kerr). Which then divided into three subgroups (n= 10) (1) Samples cured by QTH system (2) Samples cured by LED system and (3) samples cured by Flashmax system the

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