Çakıroğlu, Kübra; Güldemir, Kübra; Çakır, Özlem

Bu çalışma kapsamında, Bayburt çevresinde yetişen yabani ekşi elma (Malus sylvestris Miller) örneği dört farklıkurutma yöntemi (infrared kurutma, sıcak havada kurutma, oda sıcaklığında kurutma ve dondurarak kurutma) ile kurutulmuşve kurutulan ürünlerin fenolik madde içeriği ve antioksidan aktiviteleri belirlenmiştir. Kurutma yöntemlerine göre toplamfenolik madde içerikleri açısından en düşük değer oda şartlarında kurutulmuş elma örneğinde (34.92 mg GAE/g KM), enyüksek değer ise sıcak havada kurutulmuş örnekte (41.18 mg GAE/g KM) tespit edilmiştir. Yabani ekşi elma örneklerininantioksidan aktivite seviyeleri; FRAP yöntemine göre “dondurarak kurutma > sıcak havada kurutma > infrared kurutma >oda sıcaklığında kurutma” şeklinde, CUPRAC yöntemine göre “sıcak havada kurutma > dondurarak kurutma > infraredkurutma> oda sıcaklığında kurutma” şeklinde, β-karoten yöntemine göre ise dondurarak kurutma>sıcak havada kurutma>odasıcaklığında kurutma>infrared kurutma şeklinde değiştiği belirlenmiştir. CUPRAC metodu ile FRAP metodu arasında yüksekbir korelasyon olduğu saptanmıştır (r=0.939, R2=%88). Elde edilen deneysel verilere göre, antioksidan ve fenolik maddeiçeriği açısından yabani ekşi elma (Malus sylvestris Miller) için en iyi kurutma yönteminin sıcak havada kurutma olduğutespit edilmiştir. Renk değerleri açısından en iyi yöntemin dondurarak kurutma olduğu belirlenmiştir.

AtıfTR Dizin3

İncele

Yilmaz, Bahadir; Oruç, Seref; Mazlum, Mehmet Salih

In many countries of the world, waste management becomes compulsive with activation of laws and agreements about waste control. By this purpose, it becomes necessary and imperative to use waste asphalt materials as raw material for the new asphalt pavement due to economic advantages of using old materials, decreasing of the raw material’s potential, and problems of researching new asphalt raw mines and increasing of the asphalt pavement cost. Within this scope, this work has started to a research of re-used old materials which are completed their economic life on the road in the hot bituminous mixes. In this work, recycling methods that are used in World and Turkey are analyzed at the beginning and the advantages of recycling are utilized. İstanbul region is chosen as the working area and materials are gained by the roads that completed their economic life in İstanbul. By these materials, new coverable mix materials had produced in different ratios such as10%,25% and40%. Marshall Experiment had used to these mixtures, intensity and void analyses are made and the results that obtained from experiments are compared with the pure materials and the core samplers

AtıfTR Dizin7

İncele

Karaali, Rabi

This work presents exergy and energy analysis of a half effect parallel flow, single effect and double effect absorption systems for comparison. For the thermodynamic properties of lithium bromide-water solutions a computer program is developed by the author in FORTRAN codes for th e energy and exergy analysis. It is found that the coefficient performance (COP) and the exergetic coefficient performance (ECOP) of the double effect parallel flow absorption systems are higher than the single effect and the half effect cycles. For the do uble effect cycle COP and ECOP are found as 1.196 and 0.284, and for the single effect cycle COP and ECOP are found as 0.68 and 0.254, respectively. For the half effect cycle COP and ECOP are found as 0.455 and 0.24, respectively. The exergy loss is calculated for each component. Most of the irreversibilities are found in the evaporator and in the absorber. It is concluded that the performance of the absorber and the evaporator is crucial for the three cycles. Improving and better design of the evaporator and the absorber will directly affect positively and improve the performance and the working conditions of the three cycles

İncele