BİR ÇİMENTO FABRİKASINDA DÖNER FIRIN PROSESİNİN ENERJİ ANALİZİ

Çimento fabrikaları, enerji sarfiyatı bakımından yüksek değerlere sahip sektörlerin başında yer almaktadır. Döner fırın ise, çimento fabrikalarında enerji tüketimi açısından önemli bir yere sahiptir. Dolayısıyla, tasarruf yöntemlerinin araştırılması ve uygulanabilirliği üzerine çalışmalar gün geçtikçe artmaktadır. Bu çalışmada klinker üretimi başına yaklaşık 75kW/ton enerji sarfiyatı olan bir fabrikanın döner fırın ünitesinin termodinamik analizi yapılmıştır. Bu maksatla işletme verileri göz önünde bulundurularak döner fırın ünitesine ait kütle ve enerji denklikleri oluşturulmuştur. Analizler sonucu ünitenin enerji verimi %58.6 olarak hesaplanmıştır. Yapılan analizler kayıpların fırın yüzeyinden, bacadan ve sızıntı havalardan kaynaklandığını göstermiştir. Bu sonuçlara bağlı olarak klinker üretiminde enerji verimliliğinin arttırılabilmesi için tavsiyelerde bulunulmuştur

BİR TERMİK SANTRALİN ENERJİ ANALİZİ

Bu çalışmada incelenen güç santrali, Muğla ilinin Yatağan ilçesinde faaliyet göstermektedir. Bu termik santral 3 adet 210 MW gücünde üniteye sahiptir. Yatağan Termik Enerji Üretim A.Ş' ye ait kazan, buhar türbini ve diğer ekipmanlara, nominal işletme verileri alınarak sistemin her bir bileşeni ve tüm sistem için termodinamik kanunları yardımıyla kütle ve enerji denklikleri kurularak sistemin enerji analizi yapılmıştır. Elde edilen sonuçlara göre sisteme ait enerji verimi % 35,2 olarak bulunmuştur. Sistemde bulunan ABT (Alçak Basınç Türbini), OBT (Orta Basınç Türbini), YBT (Yüksek Basınç Türbini) için sıcaklık değişimin güç üretimine ve enerji verimliliğine etkisi incelenmiştir. Ayrıca, ısıl kapasitesi daha yüksek kömür kullanıldığı taktirde güç üretiminin ve buna bağlı olarak enerji verimliliğininde fabrika için fayda sağlayacağı belirtilmiştir. Anahtar Kelimeler: Enerji, Termik Santral, Kazan, Türbin, Yatağan

Comparison of standard versus population-specific handgrip strength cut-off points in the detection of probable sarcopenia after launch of EWGSOP2

Objective: We aimed to compare European Working Group on Sarcopenia in Older People (EWGSOP2)-suggested and population-specific handgrip strength (HGS) thresholds to detect probable sarcopenia and their associations with physical-performance measures and frailty

Endothelial Progenitor Cell Levels and Extent of Post-prandial Lipemic Response

BACKGROUND AND OBJECTIVE: Due to the frequency of meal ingestion, individuals spend the majority of the day, ~18 h, in a status of post-prandial (PP) stress. Remnant-like lipoprotein particles (RLPs) are predominant in PP phase playing an important role in the development of atherosclerosis. Endothelial progenitor cells (EPCs) have been suggested to play a role in vessel wall homeostasis and in reducing atherosclerosis. However, there is no information about peripheral blood EPCs number following PP stress. We investigated the association between circulating EPCs levels and extent of PP lipemia in healthy subjects following a high-fat meal. MATERIALS AND METHODS: A total of 84 healthy subjects (42 men, 42 women) aged 17–55 years were included in the study. PP lipemic response of subjects was determined by Oral Fat-Loading Test (OFLT). All the subjects were classified on the basis of their plasma TG levels after PP lipemic stressors in categories 1 (low), 2 (moderate), and 3 (high). Circulating EPCs numbers were measured by the flow cytometry method. RESULTS: There was a significant difference in terms of lipid parameters between men and women: high-density lipoprotein cholesterol (HDL-C) was significantly lower in men than in women (p < 0.001). Total cholesterol (TC) (p = 0.004), low-density lipoprotein cholesterol (LDL-C) (p < 0.001), triglyceride (TG) (p < 0.001), and TG-AUC (p < 0.001) were significantly higher in men than in women. There was no significant difference between the genders in terms of CD34(+)KDR(+) and CD34(+)KDR(+)CD133(+)cell number and MMP-9 levels. Vascular endothelial growth factor (VEGF) levels were significantly higher in men than women (p = 0.004). TC, LDL-C, and TG were significantly higher in the 3rd category than 1st and 2nd categories (p < 0.001) in women. Age, body mass index (BMI), fat rate, TG, TC, and LDL-C were significantly higher in the 3rd category than 1st category (p < 0.001, p = 0.002, p = 0.002, p = 0.01, p = 0.007, p = 0.004; respectively), in men. Circulating numbers of EPCs in men were significantly higher in the PP hyperlipidemia group than in the low TG levels category, independently from age (p < 0.05). Circulating EPC levels showed a positive correlation with OFLT response in men (r = 0.414, p < 0.05). Also, OFLT response showed a strong positive correlation with fasting TG levels (r = 0.930, p < 0.001). EPC levels in categories of women were not different. CONCLUSION: Increased EPCs levels in subjects with different PP hyperlipidemia may be associated with a response to endothelial injury, related to increased atherogenic remnant particles at the PP phase

The effect of nimesulide on oxidative damage inflicted by ischemia–reperfusion on the rat renal tissue

Kurt, Nezahat/0000-0002-1685-5332WOS: 000350554300025PubMed: 25418059The objective of our study is to research biochemically and histopathologically the effect of nimesulide on oxidative damage inflicted by ischemia-reperfusion (I/R) on the rat renal tissue. Twenty-four albino Wistar type of male rats were used for the experiment. the animals were divided into groups as: renal ischemia-reperfusion control (RIR), nimesulide + renal ischemia-reperfusion of 50 mg/kg (NRIR-50), nimesulide + renal ischemia-reperfusion of 100 mg/kg (NRIR100), and sham groups (SG). in NRIR-50 and NRIR-100 groups were given nimesulide, and RIR and SG groups were given distilled water, an hour after anesthesia. Groups, except for the SG group, 1-h-ischemia and then 6-h-reperfusion were performed. in the renal tissue of the RIR group in which the malondialdehyde (MDA), myeloperoxidase (MPO), and 8-hydroxyguanine (8-OHGua) levels were measured, the COX-1 and COX-2 activities were recorded. Nimesulide at 100 mg/kg doses reduced the oxidant parameters more significantly than 50 mg/kg doses; on the other hand, it raised the antioxidant parameters. It has been shown that 100 mg/kg doses of nimesulide prevented the renal I/R damage more significantly than a dose of 50 mg/kg, which shows that nimesulide, in clinics, could be used in the prevention of I/R damage