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Bu çalışma da demir çelik üretiminde pota metalurjisinde (II. Metalurji) oluşan cürufun, kolemanit kullanılarak ıslahı için endüstriyel çalışma anlatılmış ve sonuçları paylaşılmıştır. Endüstriyel çalışmalar 1.300.000 ton/yıl düşük ve orta karbonlu çelik üretim kapasitesine sahip Diler Demir Çelik İşletmesinin Gebze Dilovası tesislerinde endüstriyel boyutta gerçekleştirilmiştir. Özgün olarak soğuma esnasında [gama-dikalsiyum silikat γ-Ca2(SiO4)] formunda oluşan pota cürufuna, farklı oranlarda kolemanit ilave edilerek soğuma esnasında [beta-dikalsiyum silikat β -Ca2(SiO4)] yapısına dönüşümü sağlanarak dünyada yıllık yaklaşık 30 milyon ton atığa ulaşan, taşıma, stoklama problemi olan pota cürufunun soğuma esnasında yoğunluğu artırılarak, taşınabilir, yan ürün olarak değerlendirilebilen çevre problemleri ortadan kaldırılmış ürünler haline dönüştürülmüştür. Elde edilen cürufların kimyasal analizleri ve yoğunluk ölçümleri yapılmış, XRD, SEM/EDS incelemelerine bakılmıştır. Kompakt yapının oluştuğu % B2O3/Curuf (kg/kg) oranının 1 olduğu çalışmada, elde edilen cürufların yığma yoğunluğu 1,36 dan 2,64 ton/m3 artırılmış yine aynı çalışmada çelik bünyesinde maksimum 9 ppm B endüstriyel olarak ispat edilmiştir.

This study aims to synthesize very pure form of LaB6 nanocrystals at low temperatures. The synthetic route employed involved low temperature magnesiothermic reduction process of La2O3 with a mixture of Mg, I2 and B2O3 at 90 °C. The powder mixtures were mechanically induced under Ar atmosphere for 3 h and then heat treated. The pure form of nano LaB6 powder produced by this technique is by far the most versatile route for the synthesis of nano-LaB6. From the XRD evidences of the synthesized powders, a correct reaction path for the reduction process has been elucidated. The average particle size of nano powder synthesized was estimated from SEM as well as XRD as 78 ± 12 nm and 61.3 ± 2.0 nm respectively, and the values were found to be in good agreement. The particle size determined by XRD was upon applying the Rietveld refinement method and using isotropic Lorentzian Scherrer particle broadening parameter (LX) of refined peak profiles. From the average size of the particulates and from the specific surface area of LaB6 (1.3 m2/g) as determined by BET method, the number of unit crystals that might have constituted a nano-particulate of size 61.3 ± 2.0 nm was estimated as 105 numbers from the crystallographic information of LaB6.

Production of KBH4, in the presence of KCl, B2O3 and MgH2 by means of a mechanical reaction and a dehydrogenation kinetic, constitute the main parts of this study. Operating time and reactant ratio are considered as two parameters for the mechanical reaction to obtain the maximum yield. The production process was carried out in a ball milling reactor, and the product residue was purified with ethylene diamine (EDA) and subsequently characterized by Fourier Transform Infrared Spectroscopy (FT-IR) and x-ray Diffraction (XRD) analyses. Optimum time for mechano-chemical treatment and reactant ratio (MgH2/KCl) were obtained as 1000 min and 1.0, respectively. Synthesized and commercial KBH4 were compared by hydrolysis tests in the presence of Co1−xNix/Al2O3 heterogeneous catalyst. Hydrogen generation rates, activation energy and order of the KBH4 decomposition reaction were obtained as 1578 \({\hbox{mL}}_{{{\rm{H}}_{2} }} \;\min^{ - 1} \;{\hbox{g}}_{\rm{catalyst}}^{ - 1}\), 39.2 kJ mol−1 and zero order, respectively.

Inorganic boron compounds are used inconstruction, agriculture, cosmetics, textile, ceramic, nuclear energy,military industry, electronics and automotive industry. In this study potassiumborate (xK2O.yB2O3.zH2O) which isone of these inorganic borates was produced by using boric acid and potassiumhydroxide in aqueous medium. After specifying theoretical reaction conditionsrequired for chemical reaction, different B2O3/K2Omixing ratios have been tried to obtain several products having differentpurities. Obtained products are characterized by means of chemical analyses,XRD and TG-DTA analyses and they are compared with original samples. Boraxdecahydrate, borax pentahydrate, potassium chloride, carbonate and hydroxide isused in conventional production technique of potassium pentaborate. In thisstudy it is obtained by using KOH and low sulfate boric acid which is acommercial product of Eti Mine Works General Management in laboratoryenvironment., İnorganik bor bileşikleri, inşaat,tarım, kozmetik, tekstil, seramik, cam, nükleer sanayi, askeri uygulamalar,elektronik cihazlar ve otomotiv sektöründe kullanılmaktadır. Bu çalışmadainorganik boratlardan biri olan potasyum boratın (xK2O.yB2O3.zH2O)sulu ortamda borik asit ve potasyum hidroksit kullanılarak üretimigerçekleştirilmiştir. Bu amaçla tepkimenin meydana gelmesi için gerekli teorikkoşullar belirlendikten sonra farklı kütlesel B2O3/K2Ooranları denenerek optimum koşullar elde edilmeye çalışılmıştır. Elde edilenürünlerin kimyasal analizleri yapılarak, XRD’si ve TG-DTA’ları çekilerek yapılarıkarakterize edilerek orijinal ürünlerle karşılaştırılmıştır. Gelenekselyöntemle boraks dekahidrat, boraks pentahidrat, potasyum klorür, karbonat vehidroksitle üretilen potasyum pentaborat bu çalışmada KOH ile Eti Madenİşletmeleri Genel Müdürlüğünün ticari ürünü olan düşük sülfatlı borik asitkullanılarak laboratuvar ortamında üretilmiştir.

This study explains completely feasible route to synthesize NaBH4 by means of mechano-chemical reaction, in which NaCl, B2O3 and MgH2 were utilized. Optimum reaction conditions were investigated by different values of reactant ratio and duration to reach 95% NaBH4 purity. In addition, commercial NaBFLI was hydrolyzed with Col(2) supported on activated carbon (AC). Intermediate steps of the studies were traced by means of FT-IR, XRD, SEM and EDX analyses. Activation energy of the catalyst was searched at distinct reaction temperatures and found as 36 kJ/mol. Optimum working time for ball-milling reactor and reactant ratio (MgH2/NaCl) were obtained as 1000 min and 1.0, respectively. (C) 2013 Elsevier Ltd. All rights reserved.

Konukseven, Erhan ilhan/0000-0002-3597-4222; ALTUN, Adnan/0000-0002-1328-6349; LATIFINAVID, MASOUD/0000-0002-6557-4414 WOS: 000374121500050 In this study, a novel virtual reality-based interactive method combined with the application of a graphical processing unit (GPU) is proposed for the semiautomatic segmentation of 3D magnetic resonance imaging (MRI) of the brain. The key point of our approach is to use haptic force feedback guidance for the selection of seed points in a bounded volume with similar intensity and gradient. For the automatic determination of a bounded volume of segmentation in real time, parallel computation on the GPU is used. Automatic segmentation is applied in this adjustable bounded spherical volume with a variable diameter, which is controlled according to the edge map acquired from the gradient map. The haptic force feedback is used in order to guide the user to remain in a volume, where the intensity and gradient change are under a defined threshold range. After each seed point selection, the segmentation algorithm works inside the bounded volume of the ball with an adjusted diameter. The proposed segmentation method based on force and visual feedback with the advantage of adjustable bounded volume is not only accurate and effective in narrow spaces near the boundaries of different layers, but also fast in large homogeneous spaces since the radius of the ball increases in such regions. Parallel programming on the GPU is used for computing gradient change in selected directions, which is needed for the self-adjustment of the sphere diameter. Gradient values are used for calculating the haptic force on the CPU in real time. In this study, two haptic devices are used, one for getting haptic force feedback and the other for camera guidance during 3D visualization. A comparison between manual segmentation of MRI by an expert surgeon and the proposed segmentation algorithm is done. The proposed segmentation procedure is completed 4 times faster than the manual segmentation with similar accuracy. Scientific and Technological Research Council of Turkey (TUBITAK-BIDEB)Turkiye Bilimsel ve Teknolojik Arastirma Kurumu (TUBITAK) The first author would like to thank the Scientific and Technological Research Council of Turkey (TUBITAK-BIDEB) for financial supports during his PhD studies.

In this study, a robot with different maneuvras is followed with different estimation algorithms. The mobile robot has acted first linear, then maneuver and finally linear again. It's speed is constant through the way. Standard Kalman Filter, Adaptive Kalman Filter, Extended Kalman Filter and Interacting Multiple Model consist of multiple model Kalman Filter combined of linear and non-linear model are used to follow the act of the robot. The results of these estimations are compared with each other. Multiple model Kalman Filter is the best estimation algorithm among them for this motion model.

This study deals to synthesize LiBH4 by means of mechano-chemical reaction, in which LiBO2 and MgH2 were utilized. In order to obtain 90% LiBH4 purity, optimum reaction conditions were analyzed at different values of reactant ratio and duration. In addition, commercial LiBH4 was hydrolyzed with CoI2 supported on activated carbon (AC). In order to follow up the intermediate steps of the studies FT-IR, XRD analyses have been used. Activation energy of the dehyrdogeneration reaction was searched at different reaction temperatures and determined as 33.12 kj/mol. As an optimum operation time for ballmilling were recorded as 1000 min and reactant ratio (MgH2/LiBO2) were found as 1.0. Copyright (C) 2015, Hydrogen Energy Publications, LLC. Published by Elsevier Ltd. All rights reserved.

In this study, it is aimed that to reduce environmental effects of CO2 (as a greenhouse gas), to achieve absorption of CO2 in boron solutions and to yield a mixture product with boron compounds and the NaHCO3 which is raw material input especially in glass industry. lathe laboratory scale experiments using autoclave, with different pressure, solid/liquid ratio, and different reaction times, absorption of CO2 in the boron solutions were examined and the Na-borate compounds containing NaHCO3 were produced. The characterization of the products was determined by XRD inspections and chemical analysis. In the studies, maximum 92.4% NaHCO3 bearing borate compounds was obtained. As a result of the purification of these products it was reached pure NaHCO3 by 99%. Copyright (C) 2015, Hydrogen Energy Publications, LLC. Published by Elsevier Ltd. All rights reserved.

The kinetic parameters of the thermal decomposition of boric acid have been investigated by using TGA data. Suzuki and Coats-Redfern methods have been applied for the kinetic investigation. It was determined that decomposition kinetics of boric acid occurred in two steps and both regions suitably fit a first-order kinetic model. According to Coats-Redfern method, the activation energy and frequency factor were found as 79.85 kJ·mol-1 and 3.82x 104 min-1 for region I and 4.79 kJ·mol-1 and 4.045 x 10-5 min-1 for region II, respectively. The activation energies and frequency factors were found as 4.45 kJ·mol-1 and 4.08 x108 min-1 for the Suzuki method.

Boron oxide has been found to be useful flux for the preparation of dense anorthite ceramics (CaO.Al 2O3.2SiO 2). Inexpensive starting materials of kaolinite, calcium carbonate and silica were used for anorthite ceramic production. Colemanite (2CaO.3B 2O3.5H 2O) was added into the mixtures and the effects of colemanite upon the transformation towards anorthite and on the densification were investigated between 900-1400 °C. Single phase anorthite ceramic formed at lower temperatures in boron containing mixtures. Boron containing powder compacts were sintered above 90% theoretical density at 1350 °C.