The absorption properties of charge transfer organic semiconductor TTF-TCNQ (tetrathiafulvalene-tetracyanoquhodimete ) filmsdeposited on KBr singlecrystal, quartz and glass substrates in far infrared have been investigated. An absorption edge at ?10 ??m was observed. Photoconductivity, photoconduction efficiency and gain and photocarrier's lifetime have been measured. The results show an el...

  ABSTRACT   Background: The X-ray machines used for radiodiagnosis should meet certain quality assurance (QA) programmes . These are necessary to have good quality radiographs at reasonably low exposure to patients.   Materials and Methods: Dose reduction methods in abdomen X-ray examination were carried out in 10 hospitals in Tehran. This paper presents the work, which was implemented on 200 ...

Different biological methods are gaining recognition for the production of silver nanoparticles (Ag-NPs) due to their multiple applications. The use of plants in the synthesis of nanoparticles emerges as a cost effective and eco-friendly approach. In the present study, the synthesis of silver nanoparticles by using Ziziphora tenuior L of water extraction was carried out. For this purpose the wa...

Since the discovery of photoperiodism by Garner and Allard (2), scientists have been concerned with controlling the length of day to which experimental plants or animals are exposed. If plants or animals are grown in rooms with artificial illumination it is possible to control day length precisely by operating lamps on an ordinary time clock. The experiment becomes more complicated, however, if...

This paper demonstrates that, in the mediation of light, the suprachiasmatic nucleus (SCN) functionally associates with the anterior periventricular and parvocellular paraventricular neuron systems in rats. Intact rats (group 1) and rats undergoing a hemicomplete cutting of the SCN (group 2) were housed in a dark room (2-3 weeks) and killed after an exposure to light for 10, 30 or 60 min. Other...

The internet's ability to leap borders, thwart censorship and preserve anonymity is making it a crucial tool in recruiting jihadists. Discontented western Muslim youth, even in Australia, are ripe for the message of hate of the cyber imams. I T'S A FORMIDABLE blockade: 5000 armed police and troops, 5km of security fencing, closed-circuit TV surveillance and backup muscle including army helicopt...

We studied the rate of spontaneous emission from colloidal CdSe and CdTe nanocrystals at room temperature. The decay rate, obtained from luminescence decay curves, increases with the emission frequency in a supralinear way. This dependence is explained by the thermal occupation of dark exciton states at room temperature, giving rise to a strong attenuation of the rate of emission. The supraline...

This work presents a dual-junction, single-photon avalanche diode (SPAD) with electrical μ-lens designed and simulated in 90 nm standard complementary metal oxide semiconductor (CMOS) technology. The evaluated structure can collect the photons impinging beneath the pixel guard ring, as well as the pixel active area. The fill factor of the SPAD increases from 12.5% to 42% in comparison with simi...