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Microwave absorption properties were systematically studied for double-layer carbon black/epoxy resin (cB) and ni 0.6 Zn 0.4 fe 2 o 4 /epoxy resin (F) nanocomposites in the frequency range of 8 to 18 GHz. The ni 0.6 Zn 0.4 fe 2 o 4 nanoparticles were synthesized via high energy ball milling with subsequent sintering while carbon black was commercially purchased. The materials were later incorporated into epoxy resin to fabricate double-layer composite structures with total thicknesses of 2 and 3 mm. The CB1/F1, in which carbon black as matching and ferrite as absorbing layer with each thickness of 1 mm, showed the highest microwave absorption of more than 99.9%, with minimum reflection loss of −33.8 dB but with an absorption bandwidth of only 2.7 GHz. Double layer absorbers with F1/CB1(ferrite as matching and carbon black as absorbing layer with each thickness of 1 mm) structure showed the best microwave absorption performance in which more than 99% microwave energy were absorbed, with promising minimum reflection loss of −24.0 dB, along with a wider bandwidth of 4.8 GHz and yet with a reduced thickness of only 2 mm.In order to address issues induced by high proliferation of electromagnetic interferences in both civil and military applications, efficient microwave absorbers are becoming highly desirable and necessary. For that reason, such material is required to effectively reduce the reflection of electromagnetic (EM) signals over a broad absorption bandwidth. In order to improve the performance of microwave absorption properties, microwave absorbers are designed to meet the specific requirements of simultaneously having strong absorption, wide frequency band, lightweight and small thickness. Improvements can certainly be made to the designs by physical assembling of different types of absorbents 1-5 , chemical decorated absorbents 6,7 as well as by designing multi-layer structures [8][9][10][11] .Microwave absorbers are produced using different kinds of materials including one dimensional (1D) materials such as carbon nanotubes 12-15 , two dimensional (2D) materials such as graphene 16,17 and bulk three dimensional (3D) materials such as ferrites 9,18-21 . The difference in the dimensional structure of the materials would largely affect the microwave absorption performances since different kinds of structures contribute to different www.nature.com/scientificreports www.nature.com/scientificreports/ the F1/CB1 sample showed the best all round performance, in which more than 99% microwave energy was absorbed, with a reflection loss of −24.0 dB and a widest bandwidth of 4.8 GHz at −10 dB, yet it is the thinnest among the three designs, having a total thickness of only 2 mm.

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Water buffalo are an ancient component of Turkey's domestic livestock resources. Commonly referred to as the Anatolian buffalo the animal is part of the Mediterranean group which includes Syrian, Egyptian and Southeast European animals. Once quite numerous, there have been drastic reductions in their numbers since the 1970s due to intensification of dairy activities, agricultural mechanization and changing consumer preferences. The main areas of distribution are in northwest Turkey in the Marmara and Black Sea Regions. Buffalo are kept in small herds by livestock and mixed crop-livestock farmers. Milk is the main product, meat is largely a by-product of the dairy function and provision of the once-important draught power is now a minor output. Buffalo milk is used to prepare a variety of speciality products but output of both milk and meat is very low in comparison to cattle. Conditions of welfare and health status are not optimal. Internal parasites are a constraint on productivity. Some buffalo are being used for conservation grazing in the Black Sea area to maintain optimal conditions for bird life in a nature reserve. Long neglected by government there are recent activities to establish conservation herds, set up in vitro banks and undertake molecular characterization. More effort is needed by government to promote buffalo production and to engage the general public in conservation of their national heritage.

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High demand of semiconductor gas sensor works at low operating temperature to as low as 100 °C has led to the fabrication of gas sensor based on TiO2 nanoparticles. A sensing film of gas sensor was prepared by mixing the sensing material, TiO2 (P25) and glass powder, and B2O3 with organic binder. The sensing film was annealed at temperature of 500 °C in 30 min. The morphological and structural properties of the sensing film were characterized by field emission scanning electron microscopy (FESEM), energy-dispersive X-ray spectroscopy (EDX) and X-ray diffraction (XRD). The gas sensor was exposed to hydrogen with concentration of 100–1000 ppm and was tested at different operating temperatures which are 100 °C, 200 °C, and 300 °C to find the optimum operating temperature for producing the highest sensitivity. The gas sensor exhibited p-type conductivity based on decreased current when exposed to hydrogen. The gas sensor showed capability in sensing low concentration of hydrogen to as low as 100 ppm at 100 °C.

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