Herein, new prototypes of a dry cell and an H2 generator are designed to produce hydrogen and HHO (oxyhydrogen) gas, and the effect of a magnetic field on both systems is examined. Experiments are conducted in both systems; a 3.5% potassium hydroxide electrolyte is chosen because it is an alkaline type of solution with a high dissociation rate. NdFeB magnets with magnetic fluxes of 1.2 and 1.6 T are added to both systems to reveal the effect of the Lorentz force on gas production. The flow rates of HHO gas in the productions under 1.2 and 1.6 T in the HHO system are 680 and 730 ml min−1, respectively. These values show that the flow velocities were 15.4% (1.2 T) and 23% (1.6 T) greater, respectively than the values recorded without a magnetic field (MF). Additionally, the percentage of hydrogen production increased by 4% for 1.2 T and 11% for 1.6 T compared to the measured value without the MF. In addition, production costs are calculated for both systems in the study: the energy required to obtain the same flow rate as the comparison examples in the literature was lower.

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B ecause of its high mechanical, chemical and tribological properties and its potential on improving tool parts, c-BN material system attracts major research interest. c-BN has a very high hardness value (45 GPa Knoop) and has a potential to exceed that of diamond if it is understood and engineered at the microstructural level. It does not react with ferrous metal and oxygen even at high temperatures besides of its high thermal conductance and electrical resistance. Chemical stability towards ferrous metals and oxygen at high temperatures such as 1300°C, is a field that c-BN surpasses the diamond [1-3]. It was observed that when a fragment of c-BN was twice heated over 2000°C in vacuum, the material was not attacked by any of the usual acids and was only slowly oxidized in air at 2000°C [4]. By means of its great properties, c-BN is being used in production of tool steels with powder metallurgy or coating of them by PVD, coating of die steels in sheet metal forming or direct applications to final product where high wear resistance is needed [5-6]. Furthermore its antibacterial behavior creates opportunities for biomedical applications [7].

Özetçe-Sayısal filtre tasarımlarında yaygın olarak sayısal sinyal işleme teknikleri önemli bir yer tutmaktadır. Bu makalede, sayısal filtre tasarım yöntemlerinden biri olan sonlu darbe tepkili filtre kullanılmıştır. Sonlu darbe tepkili sayısal filtrelerde Fourier Seriler metodu kullanılarak elde edilen katsayıları pencereleme fonksiyonu ile örtüştürülür. Bu çalışmada yeni ve daha verimli bir pencere fonksiyonu Blackman ve üç parametreli Kosinüs Hiperbolik fonksiyonlarının birleştirilmesinden oluşturuldu. Pencere uzunluğu, fonksiyonun değişken parametreleri analiz edilerek en iyileştirilmiş değerler bulundu. Elde edilen değerler alçak geçiren (LPF), yüksek geçiren (HPF) ve bant geçiren (BPF) filtre tiplerine uygulanarak grafikler elde edildi. Diğer önerilen pencere fonksiyonlarına göre yan kazanç eğrilerinde ve tepecik karakteristiği açısından daha verimli sonuçlar elde edildi. Anahtar Kelimeler -sayısal filtreler, pencere fonksiyonları, Blackman pencere fonksiyonu, sonlu darbe tepkili sayısal filtreler (FIR).Abstract-Digital signal processing is widely used and important for digital filter design. In this paper, a new window function is presented. Window function is applied to the coefficients of the FIR Filters obtained by using Fourier Series. In literature, there have proposed some window functions until now, such as cosh window, Kaiser window, Exponential window and etc; a new and efficient wondow function is proposed with combination of Blackman Window and three adjustable parameter Cosh Window. Lots of mathematical models are applied using proposed window function. Especially, filter length and adjustable parameters of proposed window function are analyzed to find the best optimized values of them. These obtained data try to prove on known filter types, such as low pass filter, high pass filter and band pass filter. Proposed window function is succesfull for side lobe region and ripple ratio compared to other proposed window functions in literature. Keywords-digital filters, window functions, Blackman window, finite impulse response (FIR) digital filters.Şekil 2.1 Önerilen pencere fonksiyonunun α 2.2, β 0.5, γ 0.3 değişken parametreleri ile yüksek geçiren filtreler için uygulanması, N=50Şekil 2.2 Önerilen pencere fonksiyonunun α 1.3, β 1.0, γ 0.2 değişken parametreleri ile alçak geçiren filtreler için uygulanması, N=50 Şekil 2.3 Önerilen pencere fonksiyonunun α 2.5, β 0.5, γ 0.3 değişken parametreleri ile bant geçiren filtreler için uygulanması,N=50

In this study, a new electrolysis melt reactor for large-scale and low-temperature production amorphous elemental boron powders (ABP) equipped with a rotating star cathode electrode in a graphite crucible, which decreases the homogenization time of the boron salts is reported. The electrochemical deposition system has designed to produce high-purity ABP up to 25 kg capacity for a different combination of various salts in different percentage ranges in accordance with commercial production. One of the innovations of the system, the star type iron cathode is rotated bidirectionally and positioned up and down when desired, thanks to the movement transmission shaft. After the design of the melted reactor, ABP has produced using certain proportions of KCl, KBF4, and B2O3 salts. As a result, the melting time of KCl, KBF4, and B2O3 mixed salts was 3.7 h, and the production took place at a low temperature of 480 degrees. The highest cathode current density in production was measured as 1.083 A cm−2. The analyses revealed that an amorphous structured high purity (95.6%) elemental boron (B) particles were produced. The morphology and chemical composition of the highest purity B has characterized using XRD, SEM, EDS, and FTIR analysis.