Evaluation of Arabinofuranosidase and Xylanase Activities of Geobacillus spp. Isolated from Some Hot Springs in Turkey

( Canakci ),( Sabriye ),( Kadriye Inan ),( Murat Kacagan ),( Ali Osman Belduz ) 한국미생물생명공학회 2007 Journal of microbiology and biotechnology Vol.17 No.8

Soil stabilization of clay with lignin, rice husk powder and ash

Canakci, Hanifi,Aziz, Aram,Celik, Fatih Techno-Press 2015 Geomechanics & engineering Vol.8 No.1

This article presents the result of laboratory study conducted on expansive soil specimens treated with lignin, rice husk powder (RHP) and rice husk ash (RHA). The amount of lignin produced from paper industry and RHP were varied from 0 to 20% and RHA from 0 to 10% by weight. The treated specimens were subjected to unconfined compressive strength (UCS),swelling test and Atterberg limit tests. The effect of additives on UCS and atterberg limit test results were reported. It was observed that the additives and curing duration had a significant effect on the strength value of treated specimens. Generally (except the sample treated with 20% RHP for 3-day) with increasing additive and curing duration the UCS value increases. A RHP content of 15% was found to be the optimum with regard to 3-day cure UCS.

Experimental study on axial response of different pile materials in organic soil

Canakci, Hanifi,Hamed, Majid Techno-Press 2017 Geomechanics & engineering Vol.12 No.6

Sixty four tests were performed in a steel tank to investigate the axial responses of piles driven into organic soil prepared at two different densities using a drop hammer. Four different pile materials were used: wood, steel, smooth concrete, and rough concrete, with different length to diameter ratios. The results of the load tests showed that the shaft load capacity of rough concrete piles continuously increased with pile settlement. In contrast, the others pile types reached the ultimate shaft resistance at a settlement equal to about 10% of the pile diameter. The ratios of base to shaft capacities of the piles were found to vary with the length to diameter ratio, surface roughness, and the density of the organic soil. The ultimate unit shaft resistance of the rough concrete pile was always greater than that of other piles irrespective of soil condition and pile length. However, the ultimate base resistance of all piles was approximately close to each other.

Prediction of Effect of Volume Fraction, Compact Pressure and Milling Time on Properties of Al-Al2O3 MMCs Using Neural Networks

A. Canakci,T. Varol,S. Ozsahin 대한금속·재료학회 2013 METALS AND MATERIALS International Vol.19 No.3

An artificial neural network (ANN) model was developed to predict the effect of volume fraction, compact pressure and milling time on green density, sintered density and hardness of Al-Al2O3 metal matrix composites (MMCs). Al-Al2O3 powder mixtures with various reinforcement volume fractions of 5, 10, 15%Al2O3 and milling times (0 h to 7 h) were prepared by mechanical milling process and composite powders were compacted at various pressure (300, 500 and 700 MPa). The three input parameters in the proposed ANN were the volume fraction, compact pressure and duration of the milling process. Green density, sintered density and hardness of the composites were the outputs obtained from the proposed ANN. As a result of this study the ANN was found to be successful for predicting the green density, sintered density and hardness of Al-Al2O3 MMCs. The mean absolute percentage error for the predicted values didn’t exceed 5.53%. This model can be used for predicting Al-Al2O3 MMCs properties produced with different reinforcement volume fractions, compact pressures and milling times.

The Impact of Monetary Policy on Household Debt in China

Mehmet CANAKCI 한국유통과학회 2021 The Journal of Asian Finance, Economics and Busine Vol.8 No.4

There has been a massive increase in household debt in China, especially in the last five of years. Learning from past experiences, the country needs careful forecasting that may help to form new policies or make amendments to the existing ones. This research paper aims to highlight the impact of the monetary policy on household debt in China. The study covers the time period from 1996 to 2020 The study employs a cointegration test, Autoregressive Distributed Lag Bound Test (ARDL) approach, a Augmented Dicky Fuller (ADF) and PP test (PMG) and time series data. The findings suggest on a quantitative analysis using a time-series model in which gdp per capita and interest rate has a positive impact on household debt whereas, cpi doesn’t have significant impact. In a short-term variables relationship, household debt responds more to an increase in income than in the long-term. Also, the impact of interest rate changes on household debt is lower than income in the short run.The research suggests that there should be some restrictions on household debt and consumer financing provided to citizens and for this, appropriate leverage measures should be taken in order for the central bank to sustain robust macroeconomic conditions.

Effect of Weight Percentage and Particle Size of B4C Reinforcement on Physical and Mechanical Properties of Powder Metallurgy Al2024-B4C Composites

T. Varol,A. Canakci 대한금속·재료학회 2013 METALS AND MATERIALS International Vol.19 No.6

In this study, Al2024-B4C composites containing 0, 5, 10 and 20 wt% of B4C particles with two different particle sizes (d50=49 μm and d50=5 μm) as reinforcement material were produced by a mechanical alloying method. Two new particle distribution models based on the size of reinforcement materials was developed. The microstructure of the Al2024-B4C composites was investigated using a scanning electron microscope. The effects of reinforcement particle size and weight percentage (wt%) on the physical and mechanical properties of the Al2024-B4C composites were determined by measuring the density, hardness and tensile strength values. The results showed that more homogenous dispersion of B4C powders was obtained in the Al2024 matrix using the mechanical alloying technique according to the conventional powder metallurgy method. Measurement of the density and hardness properties of the composites showed that density values decreased and hardness values increased with an increase in the weight fraction of reinforcement. Moreover, it was found that the effect of reinforcement size and reinforcement content (wt%) on the homogeneous distribution of B4C particles is as important as the effect of milling time.

Microstructure, Electrical Conductivity and Hardness of Multilayer Graphene/ Copper Nanocomposites Synthesized by Flake Powder Metallurgy

T. Varol,A. Canakci 대한금속·재료학회 2015 METALS AND MATERIALS International Vol.21 No.4

In this study, the influence of multilayer graphene content on the green and sintered properties of the multilayer graphene/Copper nanocomposites was investigated. Flake powder metallurgy, as a new production method, was employed to prepare the multilayer graphene reinforced copper matrix nanocomposites. Results showed that the increase in agglomeration content inhibited particle-particle contact during the sintering process and therefore sintered density decreased with increasing the multilayer graphene content. The green density of 8.46 g/cm3 was found for the monolithic Cu sample, which was 16.4% higher than that of the 5 wt% MLG/ Copper nanocomposites. The high conductivity value (78.5 IACs) was obtained with 0.5 wt% the multilayer graphene reinforced nanocomposites. The electrical conductivity of sintered 5 wt% the multilayer graphene/Copper nanocomposites was 61.48 IACs. When the amount of the multilayer graphene particles as higher than 3 wt%, the decreasing rate in hardness significantly increased. The decreasing rate in the hardness of the multilayer graphene/Copper nanocomposites can be attributed to decrease in density and the non-homogeneous distribution of multilayer graphene particulates in Cu matrix.

Applicability of biocementation for organic soil and its effect on permeability

Sidik, Waleed S.,Canakci, Hanifi,Kilic, Ibrahim H.,Celik, Fatih Techno-Press 2014 Geomechanics & engineering Vol.7 No.6

In past few years, the use of bacterial calcium carbonate precipitation (biocementation) has become popular as a ground improvement technique for sandy soil. However, this technique was not applied to organic soil. This study focused on bacterial calcium carbonate precipitation and its effect on permeability in organic soil. A special injection system was prepared for inducing bacterial solution to the samples. The bacterial solution supplied to the samples by gravity for 4 days in specific molds designed for this work. Calcite precipitation was observed by monitoring pH value and measuring amount of calcium carbonate. Change in the permeability was measured before and after biocementation. The test results showed that the pH values indicates that the treatment medium is appropriate for calcite precipitation, and amount of precipitated calcium carbonate in organic soil increased about 20% from untreated one. It was also found that the biocementation can be considered as an effective method for reducing permeability of organic soil. The results were supported by Scanning electron microscopy (SEM) analysis and energy-dispersive x-ray (EDX) analysis.

Determination and Characterization of Thermostable Esterolytic Activity from a Novel Thermophiic Bacterium Anoxybacilus gonensis A4

( Ozlem Faiz ),( Ahmet Colak ),( Nagihan Saglam ),( Sabriye Canakci ),( Ali Osman Belduz ) 생화학분자생물학회 2007 BMB Reports Vol.40 No.4

Use of rpoB Sequences and rep-PCR for Phylogenetic Study of Anoxybacillus Species

Kadriye Inan,Osman Belduz,Yusuf Bektas,Sabriye Canakci 한국미생물학회 2011 The journal of microbiology Vol.49 No.5

This study was conducted to investigate the applicability of rpoB, which encodes the β subunit of RNA polymerase, to be used as an alternative to 16S rRNA gene sequence similarity analysis in the thermophilic genus Anoxybacillus. Partial rpoB sequences were generated for the 14 type strains of Anoxybacillus species and 6 other strains of four Anoxybacillus species. The sequences and the phylogenetic tree of rpoB were compared with those obtained from 16S rRNA gene analysis. The rpoB gene was found to provide a better resolution for Anoxybacillus species, with lower interspecies sequence similarities. The rpoB sequence similarity analysis permitted a more accurate discrimination of the species within the Anoxybacillus genus than the more commonly used 16S rRNA gene. Furthermore, rapid and reproducible repetitive extragenic palindromic fingerprinting techniques (REP-, ERIC-, and BOX-PCR) were employed for the specimens of genus Anoxybacillus. Through comparison of the three methods, it was found that the BOX-PCR method generated more informative results than REP-PCR for the studied strains; BOX-PCR profiles were more distinct for the different strains, including a higher number of bands. Rapid and reproducible repetitive extragenic palindromic fingerprinting techniques (rep-PCR) constitute a suitable molecular approach for the validation and maintenance of taxonomy within the Anoxybacillus genus. The results of this study show that rpoB and rep-PCR provide rapid and reliable methods for molecular typing of Anoxybacillus species.