The relations between null geodesic curves and timelike ruled surfaces in dual Lorentzian space $\mathbb{D}_{1}^{3}$

Yasin \"{U}nl\"{u}t\"{u}rk,S\"{u}ha Y\i lmaz,Cumali Ekici 호남수학회 2019 호남수학학술지 Vol.41 No.1

In this work, we study the conditions between null geodesic curves and timelike ruled surfaces in dual Lorentzian space. For this study, we establish a system of differential equations characterizing timelike ruled surfaces in dual Lorentzian space by using the invariant quantities of null geodesic curves on the given ruled surfaces. We obtain the solutions of these systems for special cases. Regarding to these special solutions, we give some results of the relations between null geodesic curves and timelike ruled surfaces in dual Lorentzian space.

Design of novel electrode for capacitive deionization using electrospun composite titania/zirconia nanofibers doped-activated carbon

Yasin, Ahmed S.,Mohamed, Ibrahim M.A.,Park, Chan Hee,Kim, Cheol Sang Elsevier 2018 Materials letters Vol.213 No.-

<P><B>Abstract</B></P> <P>Well-dispersed TiO<SUB>2</SUB>/ZrO<SUB>2</SUB> nanofibers-doped activated carbon (AC/TiZr) were successfully synthesized as an electrode for the capacitive deionization (CDI) technique via electrospinning that was followed by a hydrothermal treatment. SEM, TEM, XRD, XPS and EDX measurements were employed to characterize the morphology, crystal structure and chemistry composition of the as-synthesized material. The electrochemical performance of the AC/TiZr nanocomposite modified electrode was measured using systematic cyclic voltammetry (CV) experiments. The highest specific capacitance for the AC/TiZr-based electrode is 251.3 Fg/g, which is higher than those of the AC (207.4 Fg/g) and TiO<SUB>2</SUB>/ZrO<SUB>2</SUB> NFs (0.4 Fg/g)-based electrodes, and the interior resistance was also reduced. A desalination performance enhancement was obtained in the case of the AC/TiZr and the electrosorptive is 2.96 mg g<SUP>−1</SUP>. The implementation of the AC/TiZr nanocomposite provided a high potential for improving the efficiency of CDI.</P> <P><B>Highlights</B></P> <P> <UL> <LI> Effective TiO<SUB>2</SUB>/ZrO<SUB>2</SUB> NFs incorporated AC are introduced for CDI. </LI> <LI> Improvement in wettability (16.9°) is due to modifying the carbon-based electrode. </LI> <LI> Low inner resistance and high specific capacitance are observed. </LI> </UL> </P> <P><B>Graphical abstract</B></P> <P>[DISPLAY OMISSION]</P>

A new description of spherical images associated with minimal curves in the complex space $\mathbb{C}^{4}$

Yasin Unluturk,Suha Yilmaz 호남수학회 2022 호남수학학술지 Vol.44 No.1

In this study, we obtain the spherical images of minimal curves in the complex space in $\mathbb{C}^{4}$ which are obtained by translating Cartan frame vector fields to the centre of hypersphere, and present their properties such as becoming isotropic cubic, pseudo helix, and spherical involutes. Also, we examine minimal curves which are characterized by a system of differential equations.

Enhanced desalination performance of capacitive deionization using zirconium oxide nanoparticles-doped graphene oxide as a novel and effective electrode

Yasin, A.S.,Mohamed, H.O.,Mohamed, I.M.A.,Mousa, H.M.,Barakat, N.A.M. Elsevier Science B.V 2016 Separation and purification technology Vol.171 No.-

Due to its eco-friendly and low energy technique for removing salt ions from saline water, capacitive deionization (CDI) is highly recommended as a desalination process. Based on its good features, large surface area and good electric conductivity, graphene oxide is a promising electrode in the CDI technology if the specific capacitance could be enhanced. In this study, to improve the electrochemical performances, novel ZrO<SUB>2</SUB> nanoparticles-incorporated graphene oxide nanosheets with different concentrations were successfully synthesized by hydrothermal treatment, their electrosorption characteristics in CDI unit were examined. The morphology, structure and electrochemical performance of the fabricated materials were investigated by scanning electron microscopy, transmission electron microscopy (TEM), X-ray diffraction (XRD), cyclic voltammetry and electrochemical impedance spectroscopy. The capacitive and electrosorption performances in NaCl solution were studied. Moreover, the role of ZrO<SUB>2</SUB> loading was investigated. The introduced ZrO<SUB>2</SUB>-doped graphene oxide showed a distinct improvement in the electrosorption capacity and revealed higher specific capacitance compared to the pristine graphene oxide. The obtained results indicated that the synthesized ZrO<SUB>2</SUB>-doped graphene oxide nanocomposite having 10wt.% ZrO<SUB>2</SUB> displayed a significant increase in the specific capacitance as the corresponding value (452.06F/g) was nine folds more than that of the pristine GO at 10mV/s. Moreover, the same electrode exhibits great cycling stability, excellent salt removal efficiency (93.03%), and distinct electrosorptive capacity (4.55mg/g). Overall, the proposed GO/ZrO<SUB>2</SUB> nanoparticle composite electrode is appropriate for utilizing as optimum electrodes for the CDI technique.

Chemical, Antioxidant and Sensory Profiling of Vitamin K-rich Dietary Sources

Yasin, Muhammad,Butt, Masood Sadiq,Yasmin, Adeela,Bashir, Shahid The Korean Society for Applied Biological Chemistr 2014 Applied Biological Chemistry (Appl Biol Chem) Vol.57 No.2

In present research, vitamin K-rich dietary food products were prepared from spinach & soybean and evaluated for nutritional factors, phylloquinone and menaquinone-7 (MK-7) contents and sensory attributes. For the purpose, two spinach-based products (fresh cooked spinach (FCS), reconstituted spinach (RS), and fermented soybean (natto A; NA and Natto B; NB) were formulated. Nutritional composition indicated that natto were rich in protein and fat compared to spinach-based products. They also contained appreciable amount of mineral i.e. potassium, magnesium, calcium zinc, sodium cupper, and iron. High performance liquid chromatography revealed that FCS contained $368.81{\pm}13.96{\mu}g/100g$ of phylloquinone followed by $270.07{\pm}9.45{\mu}g/100g$ in RS, whereas minimum value $26.90{\pm}0.94{\mu}g/100g$ was observed in NA. However, maximum MK-7 concentration was recorded in NA at $803.82{\pm}21.14{\mu}g/100g$ trailed by NB $681.35{\pm}16.85{\mu}g/100g$. On the contrary, MK-7 was not detected in the spinach-based products. Antioxidant indices of products indicated that spinach-based products contained higher amount of the total phenolic content, DPPH free radical-scavenging activity, ferric reducing antioxidant power (FRAP), and antioxidant activity compared to natto. Sensory response of the products showed that spinach-based products attained higher scores than those of natto A and B. Conclusively, FCS and NA contained sufficient amount of phylloquinone and MK-7 along with antioxidant activity and has higher potential to modulate the coagulation and bone related abnormalities.

The Determination of Elementary School Students` Successes in Choosing an Operation and the Strategies They Used While Solving Real-World Problems

Yasin Soylu 韓國數學敎育學會 2007 수학교육연구 Vol.11 No.4

A new replaceable fuse for moment resisting frames: Replaceable bolted reduced beam section connections

Yasin O. Özkılıç 국제구조공학회 2020 Steel and Composite Structures, An International J Vol.35 No.3

This paper describes a new type of replaceable fuse for moment resisting frames. Column-tree connections with beam splice connections are frequently preferred in the moment resisting frames since they eliminate field welding and provide good quality. In the column-tree connections, a part of the beam is welded to the column in the shop and the rest of the beam is bolted with the splice connection in the field. In this study, a replaceable reduced beam section (R-RBS) connection is proposed in order to eliminate welding process and facilitate assembly at the site. In the proposed R-RBS connection, one end is connected by a beam splice connection to the beam and the other end is connected by a bolted end-plate connection to the column. More importantly is that the proposed R-RBS connection allows the replacement of the damaged R-RBS easily right after an earthquake. Pursuant to this goal, experimental and numerical studies have been undertaken to investigate the performance of the R-RBS connection. An experimental study on the RBS connection was used to substantiate the numerical model using ABAQUS, a commercially available finite element software. Additionally, five different finite element models were developed to conduct a parametric study. The results of the analysis were compared in terms of the moment and energy absorption capacities, PEEQ, rupture and tri-axiality indexes. The design process as well as the optimum dimensions of the R-RBS connections are presented. It was also demonstrated that the proposed R-RBS connection satisfies AISC criteria based on the nonlinear finite element analysis results.

A NEW MODELLING OF TIMELIKE Q-HELICES

( Yasin Ünlütürk ),( Cumali Ekici ),( Doǧan Ünal ) 호남수학회 2023 호남수학학술지 Vol.45 No.2

In this study, we mean that timelike q-helices are curves whose q-frame fields make a constant angle with a non-zero fixed axis. We present the necessary and sufficient conditions for timelike curves via the q-frame to be q-helices in Lorentz-Minkowski 3-space. Then we find some results of the relations between q-helices and Darboux q-helices. Furthermore, we portray Darboux q-helices as special curves whose Darboux vector makes a constant angle with a non-zero fixed axis by choosing the curve as one of the types of q-helices, and also the general case.

Effect of polyfunctional monomers on properties of radiation crosslinked EPDM/waste tire dust blend

Yasin, T.,Khan, S.,Nho, Y.C.,Ahmad, R. Pergamon 2012 Radiation physics and chemistry Vol.81 No.4

In this study, waste tire dust is recycled as filler and blended with ethylene-propylene diene monomer (EPDM) rubber. Three different polyfuntional monomers (PFMs) are incorporated into the standard formulation and irradiated under electron beam at different doses up to maximum of 100kGy. The combined effects of PFMs and absorbed dose on the physical properties of EPDM/WTD blend are measured and compared with sulfur crosslinked formulation. Thermogravimetric analysis showed that radiation developed better crosslinked network with higher thermal stability than sulfur crosslinked structure. The physical properties of radiation crosslinked blend are similar to the sulfur crosslinked blend. The absence of toxic chemicals/additives in radiation crosslinked blends made them an ideal candidate for many applications such as roof sealing sheets, water retention pond, playground mat, sealing profile for windows etc.

C-Reactive Protein/Albumin and Neutrophil/Albumin Ratios as Novel Inflammatory Markers in Patients with Schizophrenia

Yasin Hasan Balcioglu,Simge Seren Kirlioglu 대한신경정신의학회 2020 PSYCHIATRY INVESTIGATION Vol.17 No.9

Objective Peripheral biomarker studies in schizophrenia are insufficient to correspond to whether inflammatory markers are trait- or state-related. The main objective of this study was to compare novel biomarkers C-reactive protein/albumin ratio (CAR), neutrophil/albumin ratio (NAR), and complete blood count-derived inflammatory markers; neutrophil/lymphocyte ratio (NLR), platelet/lymphocyte ratio (PLR), monocyte/lymphocyte ratio (MLR), red-cell distribution width (RDW), and mean platelet volume (MPV) between patients with acutely exacerbated and remitted schizophrenia and healthy controls. Methods Anonymous data of a total of 618 patients with schizophrenia (179 in remission, 439 with acute exacerbation) and 445 psychiatrically and medically healthy subjects admitted to outpatient units were included. One-way ANOVA with Tukey’s HSD post-hoc test, Pearson’s correlation test, receiver operating characteristic analysis, and binomial logistic regression analysis were performed. Results CAR, NAR, NLR, PLR, MLR, RDW, MPV values were found higher in patients with schizophrenia than in healthy subjects. Except for NAR (p=0.007), none of the markers differed between acute exacerbation and remission. As a cut-off value of CAR, 0.388 differentiated patients with schizophrenia from controls (sensitivity 81%, specificity 81%). CAR, NAR, and MPV significantly predicted the diagnosis of schizophrenia. Conclusion CAR and NAR are reliable biomarkers of inflammation and a combination of inflammatory markers including CAR and NAR could be used to reflect the increased inflammatory status in schizophrenia, regardless of relapse or remission.