Kastamonu University Journal of Engineering and Sciences最新文献

A Low-Power 30MHz ,6th Order Band-pass Differential Gm-C Filter on Chip Using Floating Current Source 使用浮动电流源的低功耗 30MHz 六阶带通差分 Gm-C 片上滤波器

Kastamonu University Journal of Engineering and Sciences Pub Date : 2023-12-17 DOI: 10.55385/kastamonujes.1395608

Huseyin Demi̇rel, Arsen AHMED

引用次数: 0

Determination of the Changes in Airborne Ba and Mn Concentrations in Düzce City Center in the Last 40 Years with the Help of Cedrus atlantica Annual Rings 借助亚特兰蒂斯雪松年轮确定过去 40 年杜兹塞市中心空气中钡和锰浓度的变化情况

Kastamonu University Journal of Engineering and Sciences Pub Date : 2023-12-13 DOI: 10.55385/kastamonujes.1376637

Sümeyya Uslu, Nurcan Yi̇ği̇t

引用次数: 0

Accumulation and transfer of P and K, macronutrient elements for plants, in Corylus colurna L. stem sections Corylus colurna L. 茎切片中植物所需的大量营养元素 P 和 K 的积累与转移

Kastamonu University Journal of Engineering and Sciences Pub Date : 2023-12-11 DOI: 10.55385/kastamonujes.1374901

Ş. Kulaç, K. Key

引用次数: 0

The feasibility of using annual rings to monitor changes in boron concentrations in air 利用年轮监测空气中硼浓度变化的可行性

Kastamonu University Journal of Engineering and Sciences Pub Date : 2023-12-07 DOI: 10.55385/kastamonujes.1371765

B. Aricak, Ş. Kulaç

{"title":"The feasibility of using annual rings to monitor changes in boron concentrations in air","authors":"B. Aricak, Ş. Kulaç","doi":"10.55385/kastamonujes.1371765","DOIUrl":"https://doi.org/10.55385/kastamonujes.1371765","url":null,"abstract":"Boron is one of the most important elements on the agenda in recent years, both because it is a micronutrient for plants and because it is used in more than 250 fields in industry. Due to its intensive use and the continuous expansion of these areas of use, the concentrations of boron, which is produced more and more, are constantly increasing in receiving environments. However, boron, one of the important heavy metals, can cause significant health problems when inhaled from the air and taken into the human body. Therefore, monitoring the changes in boron concentration in the air is of great importance. In this study, the change of boron concentration in Pinus pinaster, Cupressus arizonica, Picea orientalis, Cedrus atlantica and Pseudotsuga menziesii species growing in Düzce, which is among the 5 most polluted cities in Europe, was examined on the basis of species, organ, direction and period in the last 40 years. The results of the study generally showed that boron concentrations did not change significantly on the basis of direction and year interval. Similarly, boron concentration in wood did not change significantly by species, whereas the change in boron concentration in bark was found to be statistically significant. According to the mean values, the lowest values were obtained in P. menziesii and the highest values were obtained in C. arizonica.","PeriodicalId":473268,"journal":{"name":"Kastamonu University Journal of Engineering and Sciences","volume":"39 18","pages":""},"PeriodicalIF":0.0,"publicationDate":"2023-12-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139011886","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Microstructure and hardness properties of Ni-Si3N4 composite materials produced by powder metallurgy method 粉末冶金法制备的 Ni-Si3N4 复合材料的微观结构和硬度特性

Kastamonu University Journal of Engineering and Sciences Pub Date : 2023-12-04 DOI: 10.55385/kastamonujes.1357436

Hasaneen Houssai̇n, S. Islak, U. Çalıgülü

{"title":"Microstructure and hardness properties of Ni-Si3N4 composite materials produced by powder metallurgy method","authors":"Hasaneen Houssai̇n, S. Islak, U. Çalıgülü","doi":"10.55385/kastamonujes.1357436","DOIUrl":"https://doi.org/10.55385/kastamonujes.1357436","url":null,"abstract":"In this study, the effect of the amount of Si3N4 on the microstructure and hardness properties of nickel (Ni) matrix silicon nitride (Si3N4) reinforced composite materials was investigated. Si3N4 was added to Ni at 5%, 10% and 15% by volume. The samples were produced using cold pressing and pressureless sintering technique. The sintering temperature was 1200 °C and the sintering time was 1 hour. SEM-EDS and XRD analyzes were used for the microstructure and phase formation analysis of the composites. The densities of the composites were measured according to the Archimedean principle. To determine the effect of Si3N4 on hardness properties, the microhardness of the samples was measured as Vicker. It was determined from XRD analysis that Ni, β1 (Ni3Si) and ε-Ni3Si2 phases were formed in the microstructure. As the amount of Si3N4 increased, both the experimental densities and relative densities decreased, and the amount of pores partially increased. Due to the distribution strengthening effect of Si3N4 in the Ni matrix, there was an increase in the hardness values and the highest hardness was determined as 135 HV2 with the addition of 15% Si3N4.","PeriodicalId":473268,"journal":{"name":"Kastamonu University Journal of Engineering and Sciences","volume":"139 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2023-12-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139012401","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0