Activation of NO2 by Modifying the Porphyrin Unit with Oxygen in a MnN4 Graphene Layer

In this article, the activation of N−O bonds in NO2 molecules has been investigated by Density Functional Theory (DFT) calculations. Considering the graphene-based MnN4 layer, nitrogen atoms in the porphyrin unit were sequentially replaced with oxygen atoms to create different MnNmOn/G (m+n=4 and 1<m≤4) layers. As more oxygen atoms are incorporated in porphyrin units for bare layers, the covalent character of the Mn−O bonds is switched to the transit nature with respect to Mn−N bonds. Moreover, the trend in bond strength decreasing in all oxygen-containing bonds is in line with the formation energy trends of bare layers. The same situation is also valid for the bonds between Mn−N/O. For NO2 adsorption configurations on all MnNmOn/G layers, N−O bonds in NO2 are weakened by populating/depopulating antibonding/bonding orbitals, respectively. Even if the MnN2O2(hex)/G layer has a moderate NO2 adsorption energy among the other layers, this layer provided the most significant activation over N−O bonds based on crystal orbital Hamilton population (COHP), crystal orbital bond index (COBI), and Atoms in Molecules (AIM) Bader Topological Analysis. Our results show that integrated COHP and integrated COBI values show a remarkable correlation with AIM-Bader parameters for the specific bonds which have descriptive capability over NO2 molecule activation

Soil respiration in apple orchards, poplar plantations and adjacent grasslands in Artvin, Turkey

In this study, influence of land-use type on soil respiration was investigated in poplar plantation, apple orchard (apple trees with understory grasses) and adjacent grassland sites in SeyitlerArea,Artvin, Turkey. Soil respiration was measured approximately monthly in three sampling plots in each land use type from January 2005 to November 2005 using the soda-lime technique. Mean daily soil respiration ranged from 0.63-3.59 g C m-2 d-1. Mean soil respiration in apple orchard, poplar plantation and grassland sites were 1.98, 1.45 and 1.12 g C m-2 d-1, respectively. Mean soil respiration wassignificantly greater in apple orchard than in poplar plantations and grasslands. Seasonal changes in soil respiration were related to soil moisture and temperature changes. Mean soil respiration rate correlated strongly with subsurface soil (15-35cm) pH (R = -0,73; p<0.05), sand content (R= 0.96, p<0.001), soil silt content (R= -0.75; p<0.05), soil clay content (R= -0,83; p<0.001) and organic matter content (R= 0,88; p<0.001). No significant correlations were observed between soil respiration and surface (0-15 cm) soil properties and root biomass. Overall, our results indicate that apple orchards with understory grasses have higher soil biological activity compared to poplar and grassland sites

PREDICTIVE MODELING OF CO2 – BRINE CO-INJECTION CONDITIONS IN RE-INJECTION WELLS

Emissions of greenhouse gases such as CO2 emitted at Turkish geothermal power plants are an obstacle to call geothermal energy as green power. However, recent advances in carbon capture and storage technologies have enabled low emissions by re-injecting produced CO2. The phase of injected CO2 is crucial for the success and safety of the operation. Injecting CO2 directly into a reservoir as pure gas or at supercritical state may cause the leakage of CO2 via fractures, or abandoned wells. This problem can be prevented by the dissolution of CO2 into brine prior to, or during its injection into the reservoir. Various projects have been being conducted around the world to reduce geothermal emissions. Among these projects, GECO (Geothermal Emission Control) is an EU funded project through the Horizon 2020 and aims to develop near-zero emission geothermal power plants. Through the GECO project, Zorlu Energy and METU (Turkey) aim to reduce the CO2 emissions for more green geothermal power production while maintaining the sustainability of Kızıldere (Turkey) geothermal field (KGF).The objective of this study is to calculate possible ranges of CO2 molar ratios to ensure all injected CO2 will dissolve in brine and preclude the gas formation in re-injection wells at KGF. In order to compute partial pressures of dissolved CO2 at elevated temperatures for a given CO2 molar ratio, chemical analysis of injection water was defined as a solution in PHREEQC and various amounts of CO2 were irreversibly added into the solution. Temperature range in geochemical modeling was selected from injection temperature at the well head and static temperature at reservoir level of the boreholes. Pressure profiles of the wells were calculated by assuming hydrostatic condition. The model results showed that the dissolved CO2 in the wellbore should not exceed 0.75 mole per kg water during injection. It was concluded that injection flow rates of both water and gas phases should be arranged with this constraint

Contenido en grasa y composición en ácidos grasos de semillas de avellana empaquetadas al vacío durante su almacenamiento

The fat contents and fatty acid compositions of three hazelnut cultivars; Tombul, Palaz and Kalinkara were investigated during storage at 21 °C with 60-65 % relative bhumidity. The total fat contents of kernels in vacuum packages increased significantly with storage time. It is believed that the absolute value of fat content does not increase but that the kernel water content and total weight decrease. The palmitic and oleic acid contents of stored hazelnuts increased, while linoleic acid content decreased. No significant differences were found for stearic and linolenic acids during storage.El contenido en grasa y la composición en ácidos grasos de tres cultivares de avellana (Tombul, Palaz y Kalinkara) han sido monitorizados durante su almacenamiento a 21 ºC y una humedad relativa del 60-65 %. Los porcentajes de grasa total de las semillas empaquetadas al vacío aumentaron significativamente con el tiempo de almacenamiento. Ello se cree que es debido no a que el valor absoluto de contenido graso aumente, sino a que disminuye el contenido en agua de la semilla y su peso total. Los porcentajes de ácidos palmítico y oleico aumentan en las avellanas almacenadas, mientras que el porcentaje de linoleico descendíó. No se hallaron diferencias significativas en los porcentajes de los ácidos esteárico y linoleico durante el almacenamiento

AN ARGUMENTATION BASED BLACK BOX ACTIVITY EXAMPLE ABOUT TRANSFORMATION OF ENERGY IN SCIENCE AND TECHNOLOGY EDUCATION

Argumentation draws an ascending line in contemporary teaching-learning methods. Within argumentation applications the black box activity is considered to be efficient method. In this study, the black box experiment activity was applied on the topic Transformation of Energy with grade eight elementary students in Science and Technology course. This study particularly aims at answering the questions: "How is a black box experiment activity designed in science classes?" and "What are the students' views on black box experiment activity?". The argumentation was guided by the researchers during the activity. Semi-structured interviews were carried out at the end of the activity with 26 students in order to determine their views towards the activity, to identify the deficiencies and impediments and to improve it. Descriptive analysis was used to analyze the semi-structured interviews. The results analyses showed that black box activity was considered as a meaningful making, intriguing, challenging, enjoyable and motivating activity. With a well-planned black box activity, thinking, arguing and inquiry skills can possible to easily be acquired and improve

Sjögren sendromlu annenin neonatal lupus sendromlu bebeği

Amaç: Sjögren sendromlu annenin neonatal lupus sendromu gelişen bebeğini olgu olarak sunmayı amaçladık. Olgu sunumu: Neonatal lupus sendromu NLS , Sjögren Sendromu SS ve diğer otoimmün hastalığı olan annelerin bebeklerinde anti-Ro/SSA ve anti-La/SSB antikorlarının geçişine bağlı olarak başta kardiyak tutulum oluşur. Bu yazıda SS’li annenin konjenital kalp bloğu tanısı alan ve kalıcı kalp pili uygulaması ile başarılı bir şekilde tedavi edilen NLS’li bebeği vaka olarak sunulmuştur. Sonuç: Anti-Ro/SSA ve anti-La/SSB antikoru pozitif SS gibi hastalığı olan kadınlarda gebelik boyunca NLS riski mutlaka akılda tutulmalı, fetal bradikardi saptandığında kalp bloğu akla gelmeli, intrauterin ve neonatal dönemde uygun tedavi planlanmalıdı

A Rare Cause of Acute Abdominal Pain in Childhood: Peptic Ulcer Perforation

Four children with a mean age of 12 years were referred to our emergency department with a history of abdominal pain. Examination revealed tenderness in the lower abdomen, in particular the left iliac fossa. The youngest child, who was 3 years old, also presented with shock. Abdominal X-rays revealed free air under both hemidiaphragms. Subsequent surgery was administered as the primary treatment of three patients and a partial resection was performed in the remaining one. The youngest child died and the others were discharged. These cases emphasize that although uncommon, alternate diagnoses must be kept in mind in children presenting with lower abdominal pain

True umbilical cord cyst: a case report

Umbilical cord cysts are important due to their association with fetal chromosomal abnormalities and fetal structural defects and in case of their rapid growth of umbilical cord cysts they are associated with compression of umbilical vessels and fetal distress. In this article we aimed to present a case with two umbilical cord cysts detected by ultrasonography at 31 weeks of gestation and who had delivered a healthy male fetus by cesarean section at 37 weeks of gestation. Histopathological examination of placenta and umbilical cord after birth revealed that cysts were true allantoic cysts. An additional urachal pathology and anomaly was not observed and the newborn was discharged after primary excision. As a result, we think that ultrasound examination of umbilical cord should be an important and routine part of obstetric ultrasonography