Czasopisma Uniwersytetu Przyrodniczy w Lublinie
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WEAR AND ADHESION PROPERTIES OF MULTILAYER Ti/TiN, (/TiC)/ TiCN/ TaN THIN FILMS DEPOSITED ON Ti13Nb13Zr ALLOY BY CLOSED FIELD UNBALANCED MAGNETRON SPUTTERING
No full textTi13Nb13Zr alloy stands out as an alternative to Ti6Al4V alloy for orthopaedic joint implant applications due to its low modulus of elasticity, high mechanical properties, high corrosion resistance, high biocompatibility and low modulus of elasticity, as well as con-taining no cytotoxic elements. In this study, Ti13Nb13Zr alloy was coated with TiN/TiC/TiCN/TaN multilayer thin films by pulsed -dc CFBUMS method to increase wear resistance and improve surface properties. Characterization of the deposited films were con-ducted by XRD, SEM, AFM, pin-on-disk, progressive scratch experiments. As a result, it is observed that all the coatings enhanced the tribological properties of the Ti13Nb13Zr alloy surface. The 20-layer TiN/TiC/TiCN/TaN multilayer coatings gave the best results for wear resistance and adhesion properties. Enhancing the interlayer number resulted in increased wear and adhesion resistance. In addition, it was determined that using TiC instead of TiN in the interlayers gave higher results regarding adhesion, wear, and mechan-ical properties.Scientific Research Project Committee of Idot;nonu University [FKP 2020-2092]; Ottoman Group Implant COThis scientific research has financially supported from Scientific Research Project Committee of & Idot;nonu University (No: FKP 2020-2092) and Ottoman Group Implant CO. The authors are gratefully for these supports
The effects of HAp coating layer on mechanical and optical properties at bonding interface of high-performance polymers
No full textPurpose: The effect of hydroxyapatite (HAp) coating layer on mechanical and optical properties at bonding interface of high-performance polymers (HPPs) used in computer-aided design (CAD)/computer-aided manufacture (CAM) technology was investigated in this in vitro study. Materials and methods: Two hundred-twenty specimens were divided into two material groups (n = 110): polyetheretherketone (PEEK, KERA (R) starPEEK) and polyetherketoneketone (PEKK, Pekkton (R) ivory). For mechanical testing, each group was divided into five surface pretreatment subgroups and a control group (n = 10): HAp coating (1%,3%, 5%, and 10% concentrations) and sandblasting with 110-mu m Al2O3 particles. For optical testing, each group was divided into five subgroups (n = 10): HAp coating (1%, 3%, 5%, and 10% concentrations) and control. The effects of the HAp coating on the optical changes and shear bond strength (SBS) of the specimens were investigated. Data was statistically analyzed by one-way ANOVA and Tukey's post-hoc test. Failure modes and surface properties of the specimens were examined by scanning electron microscopy (SEM) and coupled electron dispersive spectroscopy (EDS). Results: Average translucency and color change values increased with increasing HAp coating concentration in HPPs. As a result of the data, statistically significant differences were observed in terms of the effect of the HAp coating on SBS of HPPs (p < 0.05). Failure modes were examined, and mixed failure mode was observed. Conclusion: HAp coating can contribute to the improvement of both the optical properties and bond strength of the HPPs to resin composite. Clinical significance: Adhesion and color problems of high performance polymers are still under discussion. In order to solve these problems, generally focused on surface modifications of these polymers, but the effect of the HAp coating has not been investigated.Inonu University Research Project Council; [THD-2022-2897]Funding This study was funded by Inonu University Research Project Council (grant number THD-2022-2897)
Undogmatic Perspective as an Antidote to the Imperial Hubris in J. M. Coetzee's Waiting for the Barbarians
No full text[Abstract Not Available
Evaluation of the effect of various legume flour supplement on bread quality
No full textBu çalışmada, insan sağlığı üzerine olumlu etkileri kanıtlanmış çeşitli baklagil (fasulye, börülce, yeşil mercimek, kırmızı mercimek) unlarının kimyasal ve fiziksel özellikleri ile bu unların ekmek hamuruna ilavesinin hamurun reolojik ve tekstürel özelliklerine etkisi belirlenmiş ve elde edilen ekmeklerin kalite parametreleri üzerindeki etkileri değerlendirilmiştir. Söz konusu baklagil unlarının ve ekmeklerinin fonksiyonel özellikleri belirlenerek, hangi ekmeğin geleneksel ekmeğe daha yakın olduğu ve aynı zamanda fonksiyonel olarak ne kadar katkı sağladığı ile ilgili analizler gerçekleştirilmiştir. Çalışmada baklagil unlarının protein, kül ve toplam besinsel lif değerleri, tahıllardan (kontrol olarak kullanılan buğday) yüksek bulunmuştur. Baklagil unları içerisinde protein içeriği en yüksek yeşil mercimek unu, toplam besinsel lif ve kül içeriği en yüksek fasulye unu olarak tespit edilmiştir. Çalışmada baklagil unu katkısı ile hazırlanan hamurlarda, suyu absorbe etme kapasitesinin, baklagil katkısı arttıkça doğru orantılı olarak artması, baklagil unlarının yapısındaki protein ve lif miktarının artışına bağlı olduğunu düşündürmektedir. Ekmek üretiminde, fasulye, börülce ve yeşil mercimek unları sırasıyla %5, %10 ve %15 oranlarında buğday unuyla karıştırılmıştır. Baklagil un ilavesiyle hazırlanan ekmeklerin protein ve lif içeriklerinde anlamlı bir artış gözlemlenmiştir. Buğday ununa baklagil ilave ederek hazırlanan ekmeklerde, artan katkı oranlarına bağlı olarak son ürünün çeşitli besinsel özellikler bakımından zenginleştiği (protein, yağ, mineral madde, besinsel lif) belirlenmiştir. Baklagil un oranının artması ile birlikte lif oranındaki artış, ekmeklerdeki sertlik, çiğnenebilirlik, esneklik, yapışkanlık, koheziflik özelliklerinin artışına neden olmuştur. Duyusal olarak %5 oranında fasulye unu katkılı ekmek, en yüksek beğeniyi almıştır. Ekmeklerde kullanılabilecek optimum baklagil unu düzeyleri belirlenmiştir. Buğday ununa baklagil unlarının dahil edilmesi, ekmeklerin protein ve besin değerini önemli ölçüde olumlu etkilemiştir.In this study, the chemical and physical properties of various leguminous (bean, cowpea, green lentil, red lentil) flours with proven positive effects on human health and the impact of adding these flours to bread dough on the rheological and textural properties of the dough were determined. In addition, the effects of bread obtained from these flours on quality parameters were evaluated. In the study, the protein, ash, and total nutritional fiber values of legume flours were higher than those of cereals (wheat was used as a control). Among the legume flours, green lentil flour with the highest protein content and bean flour with the highest total dietary fiber and ash content were determined. A significant increase was observed in the protein and fiber contents of bread prepared with the addition of leguminous flour. In bread prepared by adding legumes to wheat flour, it was determined that the end product was enriched in terms of various nutritional properties (proteis, fat, mineral substance, dietary fiber) depending on the increasing additive rates. The increase in the fiber ratio with the increase in the legume flour ratio caused an increase in the hardness, chewiness, flexibility, stickiness, and cohesiveness properties of the bread in terms of sensory, 5% bean flour added bread received the highest appreciation. In terms of sensory, 5% bean flour added bread received the highest appreciation. The study aims to determine the optimum levels of leguminous flour used in bread and raise awareness of legume flour usability in food production applications
Dağıtım Sistemlerinde En Uygun Sayaç Yönetimi için Ekonomik İdari Kayıp Seviyesinin Belirlenmesi
No full textYasal abone sayaç hataları ve kaçak kullanımlardan oluşan idari kayıplar kurumlar için doğrudan gelir kaybı olarak ifade edilmektedir. İdareler sayaçlardan kaynaklanan kayıpların azaltılması için 10 yaşını doldurmuş sayaçları değiştirmektedir. Ancak idari kayıplarla mücadelede idare için en uygun yöntemler tespit edilmelidir. Bu nedenle her bir yöntem için maliyet ve fayda analizleri detaylıca yapılmalı, ardından strateji belirlenmelidir. Bu çalışmada en uygun sayaç yönetimi için idari kayıpların ekonomik olarak azaltılabileceği en uygun seviyenin belirlenmesi amaçlanmıştır. Bunun için öncelikle sayaç yönetim bileşenleri için fayda maliyet analiz standardı tanımlanmıştır. En uygun kayıp seviyesinin analizi için optimizasyon algoritması esas alınarak bir metodoloji geliştirilmiştir. Geliştirilen metodoloji 3 pilot bölgede uygulanmıştır. Seçilen bu bölgelerde sayaçların değiştirilmesi veya kalibre edilmesi ile elde edilecek muhtemel faydalar ve maliyetler detaylıca analiz edilmiştir. Böylece su kayıplarıyla mücadelede sayaç yönetimi ile elde edebilecek faydalı debiler tespit edilmiştir
An experimental study: Diabetic nephropathy and oxidative damage relationship
No full textAim: The increase of oxidatif stress caused by hyperglycemia in diabetes contributes to diabetic complications such as nephropathy. Experimental Diabetes Mellitus (DM) was induced with streptozotocin. Thioctic acid (TA), which has antioxidant properties, is a vital cofactor of mitochondrial respiration enzymes. This study investigated whether TA administration could reduce oxidative stress to treat diabetic nephropathy. Materials and Methods: 40 male Wistar albino rats were divided to groups: Control, DM, TA and DM+TA. TA and DM+TA group was administered 100 mg/kg/day TA daily, and blood glucose was assessed for six weeks. The superoxide dismutase, glutathione peroxidase and catalase activities, glutathione levels, malondialdehyde (MDA), protein carbonyl (PC), total antioxidant (TAS), total oxidant status (TOS) and OSI also were evaluated. Results: MDA and PC were increased, and antioxidant capacity was decreased in the diabetic groups compared to Control (p <0.05). In the DM+TA group, MDA, PC and TOS were decreased and TAS was increased compared to the DM group (p <0.05). Conclusion: TA exhibited a curative effect on diabetic nephropathy by increasing an tioxidant activity and reducing oxidative damage
Performing of stability analysis and control processes of complex order systems
No full textKlasik türev ve integralleri kompleks sayı derecelerine genelleştiren kompleks dereceli matematik, kesirli analizin bir genellemesi olarak ele alınabilir. Kompleks dereceli sistemler üzerine yapılan çalışmalar oldukça sınırlıdır ve beraberinde birçok açık problem içermektedir. Çünkü bu sistemlerin fiziksel anlamı, zaman cevaplarında karşılaşılan sanal bileşen ve bu bileşenin ölçülememesi nedeniyle tam olarak anlaşılamamaktadır. Bu sorunun üstesinden gelmek için eşlenik dereceli türev ve integral operatörleri kullanılmaktadır. Kompleks dereceli operatörler ancak eşlenik dereceli operatörüyle eşleştirildiğinde, reel değerli yanıtların ortaya çıktığı görülmüştür. Bu tez kapsamında, kompleks eşlenik dereceli sistemlerin kararlılık analizleri ve kontrol işlemlerinin gerçekleştirilmesi hedeflenmiştir. Kompleks ve kompleks eşlenik dereceli sistemlerin birim darbe ve birim basamak cevapları elde edilmiş ve karakteristik özellikleri incelenmiştir. Kompleks eşlenik dereceli sistemlerin kararlılık analizleri için grafiksel bir yöntem olan genelleştirilen değiştirilmiş Mikhailov (GD Mikhailov) kararlılık metodu bu sistemlere uyarlanmıştır. GD Mikhailov kararlılık metodu kullanılarak elde edilen sonuçlar, kutup analizi tabanlı farklı yöntemler ile kıyaslanarak doğrulanmıştır. D-ayrıştırma yöntemi ile kompleks eşlenik dereceli sistemlerin PI, PID ve kesir dereceli PI kontrolör ile kararlılaştırılması gerçekleştirilmiştir. Parametre belirsizliğine sahip kompleks eşlenik dereceli sistemlerin dayanıklı kararlılığı incelenmiştir ve bu tür sistemler için Kharitonov teoreminin ve kenar teoreminin kullanılamayacağı gösterilmiştir. Kompleks eşlenik dereceli sistem ailesinin dayanıklı kararlılık analizi değer kümelerinin görselleştirilmesi ile desteklenen sıfırın dışlanma prensibi kullanılarak ve ayrıca GD Mikhailov kararlılık kriteri tabanlı bir yöntem kullanılarak gerçekleştirilmiştir. Son olarak, parametre belirsizliğine sahip kompleks eşlenik dereceli sistemler için dayanıklı kontrolör tasarımı yapılmıştır. Anahtar Kelimeler: Kompleks dereceli sistemler, kompleks eşlenik dereceli sistemler, kesir dereceli sistemler, Mikhailov kararlılık kriteri, kararlılaştırma, parametre belirsizliği, değer kümesi, sıfırın dışlanma prensibi, dayanıklı kontrolComplex order mathematics, which generalizes the classical derivatives and integrals to degrees of complex numbers, can be considered as a generalization of fractional calculus. Studies on complex order systems are very limited and include many open problems. Because the physical meaning of these systems cannot be fully understood due to the imaginary part encountered in time responses and the inability to measure this part. To overcome this problem, the conjugate order derivative and integral operators are used. It has been observed that the real valued responses occur only when the complex order operators are paired with their conjugated orders. In this thesis, it is aimed to perform the stability analyzes and control processes of the complex conjugate order systems. The unit impulse and unit step responses of the complex order and the complex conjugate order systems are obtained and their characteristic features are investigated. The generalized modified Mikhailov (GD Mikhailov) stability method, which is a graphical method for the stability analysis of complex conjugate order systems, is adapted to these systems. The results obtained using the GD Mikhailov stability method are verified by comparing with different pole analysis based methods. The stabilization of complex conjugate order systems with PI, PID and fractional order PI controller has been performed with D-decomposition method. The robust stability of complex conjugate order systems with parameter uncertainty is investigated and it is shown that the Kharitonov theorem and the edge theorem cannot be used for such systems. The robust stability analysis of the family of complex conjugate order systems is performed using the zero exclusion principle supported by the visualization of the value sets, and also a method based on the GD Mikhailov stability criterion. Finally, the robust controller design is made for the complex conjugate order systems with parameter uncertainty. Keywords: Complex order systems, complex conjugate order systems, fractional order systems, Mikhailov stability criterion, stabilization, parameter uncertainty, value set, zero exclusion principle, robust contro
THE PROTECTIVE EFFECTS OF TETRANDRINE AGAINST TO HISTOLOGICAL, SPERMATOLOGICAL AND OXIDATIVE DAMAGE INDUCED BY AROCLOR 1254 ON THE MALE RATS REPRODUCTIVE SYSTEM
No full textObjectives: Aroclor (AR) 1254; has many adverse effects on male reproduction such as carcinogenic, teratogenic, immune and endocrine disruption problems. Tetrandrine (TET), a bisbenzillisoquinoline alkaloid isolated from the root of Stephania tetrandra S. Moore, has protective effects such as immunomodulatory, anti-cancer, and anti-inflammatory. The objective of this study was to investigate the possible curative effects of TET therapy against testicular damage (histological, spermatological and oxidative damage) induced by AR1254. Materials and Methods: Twenty-eight male rats were randomly divided into four equal-sized groups: a control group; (1 ml of corn oil by gastric oral gavage), AR1254 group; (2 mg/kg) AR1254 administered intraperitoneally), TET group; (TET by gastric oral gavage 30 mg/kg) and AR 1254 + TET group;(Aroclor 1254 and TET administered together at the same doses as the previous groups. Results: The AR1254 treatment caused morphological and spermatological damage on testis tissue; oedema vacuolization and congestion, in interstitial area, reduction in spermatogenic cells, arrested spermatocytes at different stages of spermatogenesis, shedding of spermatogenic serial cells into tubular lumens, a decline in epididymal sperm concentrations, sperm motility and a rise in abnormal sperm ratios. The AR1254 administration induced an increase in the oxidative parameters and a decrease in enzymatic and nonenzymatic antioxidant levels. The TET treatment significantly ameliorated histological, oxidative, and sperm damage caused by AR1254. Conclusion: This study demonstrated the protective effects of TET against AR1254-induced male rat reproductive damage
Khalid b. Velid el-Mahzûmî and historical personality
No full textHâlid b. Velîd b. Mugīre b. Abdullah b. Amr b. Mahzûm, ilk çocuğuna nispetle Ebû Süleyman künyesini almıştır. Hz. Peygamber'in eşlerinden Hz. Meymûne'nin yakın akrabasıdır. Babası Hâlid'in eğitimine önem vermiş ona kılıç, mızrak kullanmayı ve atabilmeyi öğretmiştir. Hâlid babasının ticaret kervanlarının başında Irak, Suriye, Mısır ve Yemen'e gitmiştir. Miladi 629 yılında Müslüman olan Hâlid b. Velîd, Seyfullah lakabını almıştır. Hz. Peygamber, ona başarılarından dolayı "Allah'ın kılıçlarından bir kılıç" demiş ve onu "ne güzel kul" diyerek övmüştür. Hâlid b. Velîd zaman zaman da eleştirilere maruz kalmış, Hz. Peygamber tarafından uyarılmıştır. Hâlid b. Velîd, Hz. Peygamber vefat ettikten sonra da ona bağlılığını içinde canlı tutmuştur. Bizans ve Sasanilere karşı yürütülen savaşlara katılmış ve zaferler kazanmıştır. Katıldığı yüze yakın savaştan muzaffer olarak ayrılmıştır. Onun fetihleri Cezire bölgesine kadar uzanmıştır. O, harbin hilelerini iyi bilen; yolcular, esirler ve casuslar vasıtasıyla düşman hakkında malumat toplayan; muharebe esnasında durum ve şartlara göre strateji üreten büyük bir komutandı. Sert mizacının yanı sıra tez canlı değildi. Her durumda çok tedbirliydi. Emrindeki askerlere iyi davranır ve onları idare etmesini bilirdi. Hâlid, vücudunda kılıç, mızrak ve ok darbesi değmedik bir yerin kalmadığını belirtmiştir. Ömrünün büyük bir kısmını savaşlarda geçiren Hâlid, savaş meydanında ölemediği için hayıflanmıştır. Anahtar Kelimeler: Hâlid b. Velîd, Mahzûm Kabilesi, Hz. Muhammed (s.a.v.), Ebûbekir, Ömer, Fetih Hareketleri, Savaş StratejileriKHâlid b. al-Walīd b. Mugīre b. Abdullah b. Amr b. Mahzûm took the name of Abu Suleiman compared to his first child. He was a close relative of Meymûne who was one of the wives of the Prophet Muhammad. KHâlid's father gave importance to KHâlid's education and taught him to use swords and spears and to throw. KHâlid went to Iraq, Syria, Egypt and Yemen at the head of his father's trade caravans. KHâlid b. Walīd's title was Saifullah. Prophet Muhammad called him "Sword of God" because of his achievements and praised him by saying "what a beautiful servant." KHâlid b. al-Walīd was also criticized from time to time, Prophet Muhammad was warned by the Prophet. After Muhammad died, KHâlid b. al-Walīd continued to fight, keeping his loyalty to him alive. He participated in the wars against Byzantium and Sassanids and won victories. He was victorious from nearly a hundred wars he participated in. His conquests extended to the Cezire region. He was a great commander who produced a strategy according to the situation and conditions during the war and who gathered information about the enemy through travelers, prisoners, and spies. He knew the tricks of fight well. Besides his fierce temperament, he was not impetuous. In any case, he was very cautious. He treated the soldiers under his command well and knew how to handle them. KHâlid stated that there was no part of his body that had not been touched by a sword, spear or arrow. KHâlid, who spent most of his life in wars, regretted that he could not die on the battlefield. Keywords: KHâlid b. Walid, Mahzûm Tribe, Prophet Muhammad, Ebû bekir, Omer, Conquest Movements, War Strategie
Betonarme Prefabrik Endüstri Yapılarının 6 Şubat 2023 Depremleri Sonrası Hasarlarının İncelenmesi
No full textOn February 6, 2023, two devastating earthquakes occurred in Kahramanmaraş on the same day. In this study, the damages occurred in two reinforced concrete precast industrial structures after the Pazarcık (Mw 7.7) and Elbistan (Mw 7.6) earthquakes were investigated. There are different types of moment-transmitting and non-moment-transmitting connection types for precast structures in the Türkiye Building Earthquake Code (TBDY 2018), non-moment-transferring pinned connections are generally preferred in practice. Although pinned connections provide fast and practical application, they suffer brittle damages during earthquakes. In addition, there is a risk of out-of-plane collapse of the beams in these joints. In the field investigations, serious brittle damages were observed in the joints with pinned connections. When the earthquake damages are examined, it is seen that the joining methods that will provide ductile behaviour should be preferred in reinforced concrete precast structures. © 2023 AESSRA. All rights reserved