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Bu çalışma Batı Karadeniz Bölgesi’nde yer alan Sakarya ili fındık bahçelerinde Fındık kurdu Curculio nucum L. (Colepotera: Curculionidae) ve Fındık yeşil kokarcası Palomena prasina L. (Hemiptera: Pentatomidae)’nın zarar oranlarını belirlemek amacıyla 2017-2018 yıllarında yürütülmüştür. Çalışmanın ilk yılı, Fındık kurdu’nun zararı nedeniyle oluşan delikli meyve %0.8-1.8 ve boş iç %8.2-11.5, ikinci yıl ise delikli meyve %0.0-0.2 ve boş iç %7.4-10 olarak bulunmuştur. İlk yıl, Fındık yeşil kokarcası zararı olan şekilsiz iç oluşumu %0.7-1.4 ve lekeli iç %0.5-1.1, ikinci yıl şekilsiz iç oluşumu %1.2-1.9 ve lekeli iç %0.7-1.3 olarak belirlenmiştir. Bu iki türün ortak zararı olan sarı karamuk ve kara karamuk yıllara göre sırasıyla %1.8-3.2 ve %13.5-21.9 olarak belirlenmiştir.

There may be condensation on the fin surfaces of the air conditioning systems due to the temperature of the fin surfaces being below the dew point temperature of the water vapor in the surrounding air. Heat and mass transfer occur from the saturated air layer to the liquid water film and the latent heat of condensation is transferred to the fin. This study presents a quasilinearization solution for vertical rectangular fins when condensation occurs, assuming that the average convective heat and mass transfer coefficients are constant along the height of the fin. Rectangular fins with and without condensation on the surface have been compared and optimum fin dimensions have been given. The optimum fin length, the fin effectiveness and the average fin temperature in the case of condensation were found to be smaller than in the case of no condensation.

The article is devoted to calculations of load on rollers of a curvilinear continuous casting machine during bending of the ingot in the levelling section. The calculation takes into account the elastic and plastic characteristics of metal and the flexibility of the roller apparatus. Determination of load on rollers together with meeting other requirements such as reducing the cooling water consumption, minimizing the energy consumption enables optimizing the technology of slab cooling in the secondary cooling zone (SCZ) and obtaining metal of the required quality.

In this study, a comprehensive exergy analysis was applied to a solar power system (SPS) located in the city of Van, Turkey. Van was always known as a sun city throughout history with the name of TUSBA. It has an average of 300 sunny days a year, an altitude of 1727 m, and an average daily temperature of 9.85°C. Considering how the need for sustainable and renewable energy sources - and knowledge over them - constantly increases, this SPS was built to reveal the true solar potential of the campus area of Yuzuncu Yil University of the city of Van, hopefully as a precursor for further large-scale SPS constructions in the region. A daily analysis considering energy production and global radiation was applied to the system in 2013 for 365 days. It was found that the yearly exergy efficiency of the system was 10% and total electrical energy production was 31,038.95 kWh, averaging 1763.5 kWh/kWp yearly.

Abstract In this study, photoelectrochemical performance of reduced graphene oxide (RGO)-CdxZn1-xS composites, which were synthesized through a novel two-steps thermal sulfurization process by using elemental sulfur, was reported. This is the first time that the two-step thermal sulfurization process with elemental sulfur for the preparation of photoanode based on RGO-CdxZn1-xS. The electrodes exhibited high photostability and photocurrent response in the presence of visible light. The presence of RGO in CdxZn1-xS as electron collector and transporter increased the photocurrents approximately 40%. Among the RGO-CdxZn1-xS composites, RGO-CdS photoanode yielded an extremely high photocurrent density of 6.5 mAcm−2 with the rate of hydrogen production rate of 551.1 μ m o l h − 1 c m − 2 . This value of photocurrent density is almost 89% of its theoretical value. This is the maximum attained photocurrent density with superior stability in comparison with related literature.

The temperature dependence of the electrical conductivity of the molten eutectic GdCl3(0.515)–KCl(0.485) containing up to 3.3 mol % gadolinium oxide is studied. The temperature dependences of the conductivity of the molten GdCl3–KCl–Gd2O3 system are approximated by second-order polynomials. The formation of gadolinium oxychlorides is confirmed by spectral studies of the solidified melt.

Two approaches to synthesis of unsymmetrical disulfides based on different types of thiol activation, namely, an electrochemical method in the presence of a redox mediator and a microwave irradiation, were discussed. The mediated electrosynthesis procedures were carried out by the oxidative coupling of thiols or by the thiol-disulfide exchange in the presence of redox pairs—substituted o-aminophenol/o-iminobenzoquinone. It has been established that the formation of unsymmetrical disulfides under electrochemical conditions occurs as a result of both the oxidative coupling of sulfur-centered radicals, and a redox-mediator promoted thiol-disulfide exchange, which led to a high yield of heterodimeric products (89%–99%). The microwave-assisted synthesis made it possible to obtain the target products with yields of 13%–86% depending on different irradiation parameters such as power, temperature, and irradiation duration. However, this method requires a rigorous selection of conditions for each reaction and is therefore inferior to the electrochemical approach.

Beyond the anticipated experience associated with tourism destinations, the United Nations World Tourism Organization (UNWTO) has further tasked (especially the destination countries) on the importance of tourism to achieving the 2030 Sustainable Development Goals (SDGs). From this dimension, this study employed the ecological footprint of the 10 most visited countries (France, Spain, United States, China, Italy, Mexico, United Kingdom, Turkey, Germany, and Thailand) over the period 1995-2016. Specifically, the study employed an econometric approach and found that increase in tourism arrivals and globalization is detrimental to the attainment of sustainable environmental quality in a long term. Precisely, a 1% increase in international arrivals and globalization is responsible for a 0.18 and 0.89% increase in ecological footprint in the long-run. These impacts of tourism activities and globalization are detrimental to the environmental quality of the destination countries. Meanwhile, the real income per capita and biocapacity in the destination countries improve the environmental quality of the panel of destination countries in the long-run. In addition, the study found significant evidence of Granger causality from tourism and real income to ecological footprint without feedback, the globalization-ecological footprint Granger causality nexus is with feedback. Moreover, potentially effective policies for government and other stakeholders especially toward attaining Global goals were proffered in the study.