Chemical vapour deposition (CVD) is a promising method for producing largescale graphene (Gr). Nevertheless, microscopic inhomogeneity of Gr grown on traditional metal substrates such as copper or nickel results in a spatial variation of Gr properties due to long wrinkles formed when the metal substrate shrinks during the cooling part of the production cycle. Recently, molybdenum (Mo) has emerged as an alternative substrate for CVD growth of Gr, mainly due to a better matching of the thermal expansion coefficient of the substrate and Gr. We investigate the quality of multilayer Gr grown on Mo and the relation between Gr morphology and nanoscale mechanical and electrical properties, and spatial homogeneity of these parameters. With atomic force microscopy (AFM) based scratching, Kelvin probe force microscopy, and conductive AFM, we measure friction and wear, surface potential, and local conductivity, respectively. We find that Gr grown on Mo is free of large wrinkles that are common with growth on other metals, although it contains a dense network of small wrinkles. We demonstrate that as a result of this unique and favorable morphology, the Gr studied here has low friction, high wear resistance, and excellent homogeneity * Corresponding author Email address: bvasic@ipb.ac.rs (Borislav Vasić) of electrical surface potential and conductivity. 1

-Diatom samples were collected during July 2010 at 15 localities from different types of substrate (stone surfaces, sand, mud, fi lamentous algae and submerged mosses) from the Dojkinci River. During the research period, 124 taxa were determined within 43 genera. Among numerous common diatoms we recorded three taxa for the fi rst time in Serbia: Brachysira intermedia (Øst.) Lange-Bertalot, Chamaepinnularia mediocris (Krass.) Lange-Bertalot and Navicula tridentula Krass. Also, we observed 21 taxa which are rarely recorded taxa for Serbia. The most interesting was Diatomella balfouriana Grevill. that was previously known only from the River Tisa near Titel. In the studied material, it was identifi ed only in samples collected from the surface of boulders with mosses at the third locality. Their morphology, distribution and ecology are presented in this paper.

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Microphones exploit the motion of suspended membranes to detect sound waves. Since the microphone performance can be improved by reducing the thickness and mass of its sensing membrane, graphene-based microphones...

A temperature sensor based on four thin-film resistors is presented. Four resistors are made in the form of thin metal layer meanders on the surface of a silicon chip. Two resistors are covered with a layer of 2.3 µm thick hard baked photoresist. Two other resistors are exposed to ambient air. The photoresist cover on two of the resistors makes a mismatch in the temperature coefficient of resistance between the covered and exposed resistors, thus enabling functionality of the system as a temperature sensor. The resistors are connected in the Wheatstone bridge configuration in order to enhance the sensitivity of the structure. Resistor meanders are 500 µm  ×  500 µm in lateral dimensions, each consisting of a 10 µm wide metal strip with 10 µm clearance between the strips. The total length of each strip is 12.5 mm. The material used for the meanders is 100 nm thick sputtered gold. The sensor was tested in a temperature chamber in the range from 80 °C to  −50 °C. The matching between the sensor’s output and the readings obtained by the Pt1000 reference sensor was within  ±0.1 °C (static), but the influence of water vapor adsorption at the exposed resistors surface on temperature measurements was visible. The sensor has potential applications in temperature measurements in air.