Metal-coated carbon nanotube tips for Magnetic Force Microscopy

We fabricated cantilevers for magnetic force microscopy with carbon nanotube tips coated with magnetic material. Images of a custom hard drive demonstrated 20 nm lateral resolution, with prospects for further improvements.Comment: Accepted to be published in Applied Physics Letter

Using computer-assisted optimum bucking method in producing log

Orman ürünlerinin üretiminde ağaçtan elde edilecek toplam ekonomik değerleri en yüksek miktara çıkarmak için bütün muhtemel boylama kombinasyonları hızla değerlendirilmeli ve bunlar arasından optimum boylama kombinasyonu seçilmelidir. Birçok alternatif çözüm içeren bu tip problemlerin sistematik olarak çözülebilmesi için bilgisayar destekli yöntemlere gereksinim duyulmaktadır. Bu çalışmada, ağ analizi tabanlı NETWORK 2001 yazılımı kullanılarak tek ağaç düzeyinde optimum boylama yöntemi uygulanmıştır. Uygulama, Artvin Orman Bölge Müdürlüğü, Ardanuç Orman İşletme Müdürlüğü, Ovacık Orman İşletme Şefliği sınırlarında yer alan Kafkas Göknarları (Abies nordmanniana) üretim sahasında gerçekleştirilmiştir. Daha sonra, optimum boylama yönteminden elde edilen sonuçlar ile geleneksel boylama yönteminin sonuçları karşılaştırılmıştır. Sonuçlar, optimum boylama yönteminin üretilen ağaçların toplam ekonomik değerlerini %12’ye kadar (ortalama %5,20) arttırabileceğini göstermiştir. Ayrıca, optimum boylama yönteminin uzun ve kalın çaplı tomruklara sahip yüksek hacimli ağaçlarda daha iyi sonuç verdiği bulunmuşturIn order to maximize total economic value of a tree during extraction of forest products, all of the possible bucking combinations should be quickly evaluated and optimum bucking combination should be selected among them. The computer-assisted methods are required to systematically solve such problems with many alternative solutions. In this study, single tree level (stem-level) optimum bucking method was implemented by using network analysis based NETWORK 2001 software. The application was conducted in a harvesting unit of Caucasian Fir (Abies nordmanniana) stand located in Forest Regional Directorate of Artvin, Forest Enterprise Directorate of Ardanuç, Forest Enterprise Chief of Ovacık. Then, the results from optimum bucking method were compared with the results from the traditional bucking method. The results indicted that optimum bucking method increased the total economic values of harvested trees up to 12% (average 5.2%). Besides, it was found that optimum bucking method provided better results for high-volume trees with long and large diameter logs

MEKANİK ORMANCILIK ARAÇLARININ BİRİM MALİYETLERİNİN MİCROSOFT EXCEL TABANLI PROGRAM İLE HESAPLANMASI

Ülkemizde mekanik ormancılık araçlarından daha verimli ve etkin bir biçimde yararlanılabilmesi için bu araçların ekonomik analizleri yapılarak birim maliyetleri belirlenmelidir. Bu çalışmada, mekanik ormancılık araçlarının birim maliyetlerini hesaplayan Microsoft Excel tabanlı bir program (Maliyet Analizi 1.5) geliştirilmiş ve ülkemizde ormancılık çalışmalarında yaygın olarak kullanılan mekanik araçlardan bazılarının verimlilik ve planlanmış kullanma saatlerine göre birim maliyetleri hesaplanmıştır. Ayrıca, birim maliyeti etkileyen temel faktörler ortaya konulmuştur. Sonuçlara göre birim maliyeti en çok etkileyen parametrelerin başında satın alma fiyatı, ekonomik ömür, motor gücü, birim yakıt fiyatı ve verimlilik oranı gelmektedir. Anahtar kelimeler: Mekanik orman araçları, Birim maliyet, Mekanizasyon, Ekonomik analiz

Ultra-High Yield Growth of Vertical Single-Walled Carbon Nanotubes: Hidden Roles of Hydrogen and Oxygen

An oxygen assisted hydrocarbon chemical vapor deposition (CVD) method is developed to afford large-scale highly reproducible ultra high-yield growth of vertical single-walled carbon nanotubes (SWNT). It is revealed that reactive hydrogen (H)-species, inevitable in hydrocarbon-based growth, are damaging to the formation of sp2-like SWNTs. The addition of oxygen scavenges H-species and provides a powerful control over the C/H ratio to favor SWNT growth. The revelation of the roles played by hydrogen and oxygen leads to a unified and universal optimum growth condition for SWNTs. Further, a versatile method is developed to form vertical SWNT films on any substrate, lifting a major substrate-type limitation for aligned SWNTs.Comment: 14 pages of text and 6 figure

Early Geometrical Thinking in the Environment of Patterns, Mosaics and Isometries

This book discusses the learning and teaching of geometry, with a special focus on kindergarten and primary education. It examines important new trends and developments in research and practice, and emphasizes theoretical, empirical and developmental issues. Further, it discusses various topics, including curriculum studies and implementation, spatial abilities and geometric reasoning, as well as the psychological roots of geometrical thinking and teacher preparation in geometry education. It considers these issues from historical, epistemological, cognitive semiotic and educational points of view in the context of students' difficulties and the design of teaching and curricula

Model for replication potential

This report is a deliverable for the REMOURBAN (REgeneration MOdel for accelerating the smart URBAN transformation) project which is a HORIZON 2020 programme project. Deliverable 5.2 was aimed at the development of a model for replication potential

Olopatadine hydrochloride loaded Kollidon ® SR nanoparticles for ocular delivery: Nanosuspension formulation and in vitro–in vivo evaluation

Introduction: Allergic eye diseases includes a spectrum of diseases, with each state being characterized by a complicated immunopathology. In the present study, polymeric Kollidon ® SR nanoparticles loaded with olopatadine hydrochloride (OLO) were formulated as a suspension for ocular drug delivery. The formulations were developed to treat ocular allergic disease and characterized by their improved duration of corneal retention. Methods: OLO-loaded Kollidon ® SR nanoparticles were prepared using the spray-drying method. The active agent was quantified using ultra-high performance liquid chromatography (U-HPLC). The nanoparticles were characterized according to entrapment efficiency, particle size, zeta potential, morphology, solid-state characterizations, and drug release. The in vitro release studies on OLO-loaded nanoparticles were examined in simulated tear fluid (pH 7.4). In vivo studies were conducted on healthy female/male Anatolian Merino sheep to investigate the retention time of the active agent. Results and Discussion: Characterization studies showed that OLO was successfully loaded into the nanoparticle system and that the suspension formulation is suitable for ocular administration. Using DDSolver, the in vitro release of the OLO from nanoparticle formulations followed the Korsmeyer-Peppas model. Conclusions: The proposed spray-drying method can be successfully applied for preparing OLO-loaded nanoparticles without adding crosslinkers. OLO-loaded nanoparticles appear to be a promising extended-release drug delivery system that can be used to treat ocular diseases with a more prolonged drug-residence time on the ocular surface. © 2019 Elsevier B.V