Graphene revealed a number of unique properties beneficial for electronics. However, graphene does not have an energy band-gap, which presents a serious hurdle for its applications in digital logic gates. The efforts to induce a band-gap in graphene via quantum confinement or surface functionalization have not resulted in a breakthrough. Here we show that the negative differential resistance ex...

Materials exhibiting negative differential resistance have important applications in technologies involving microwave generation, which range from motion sensing to radio astronomy. Despite their usefulness, there has been few physical mechanisms giving rise to materials with such properties, i.e. GaAs employed in the Gunn diode. In this work, we show that negative differential resistance also ...

This communication reports an asymmetric charge transport with a large rectification ratio and finely featured NDR (negative differential resistance) by d-orbitals of a neutral ruthenium(ii) complex with a C(2) axis of symmetry.

background and objectives: non-fementer gram-negative bacilli (nfgb) are ubiquitous pathogen that has emerged as a major cause of health care associated infections. the aim of this study was to determine the prevalence and antimicrobial susceptibility of   nfgb in an iranian hospital. materials and methods: fromjuly 2005 to november 2006 a total of 257 strains of nfgb including 109 (42.41%) str...

conclusions our results showed the rate of effects of different risk factors on imipenem resistance. regarding the studied risk factors, appropriate programs must be set in place to control and prevent imipenem resistance in gram-negative bacteria. results of the 374 isolated, 134 were imipenem resistant, and 240 were sensitive to imipenem. the resistance rate was more common in males and in pa...

b a ckground: cockroaches are among the medically important pests found within the human habitations that cause serious public health problems. they may harbor a number of pathogenic bacteria on the external surface with anti- biotic resistance. hence, they are regarded as major microbial vectors. this study investigates the prevalence and antibiotic resistance of gram-negative pathogenic bacte...

The traditional implementation of resonant tunneling diodes (RTD) as a high-frequency power source always requires the utilization of negative-differential resistance (NDR). However, there are inherent problems associated with effectively utilizing the two-terminal NDR gain to achieve significant levels of output power. This paper will present a new design methodology where resonant tunneling s...