Anvar A. Zakhidov

Bio: Anvar A. Zakhidov is an academic researcher from University of Texas at Dallas. The author has contributed to research in topics: Perovskite (structure) & Carbon nanotube. The author has an hindex of 63, co-authored 417 publications receiving 27644 citations. Previous affiliations of Anvar A. Zakhidov include University of Texas System & Business International Corporation.

Theory of the nonlinear all-optical logical gates based on PBG structures

Abstract: In our work, we show that photonic bandgap (PBG) systems containing nonlinear insertions are of interest for possible applications as the all-optical adders and logical gates Two principal schemes of an all-optical adder based on the combined 1D-3D PBG materials containing optically nonlinear layers are discussed Due to the electromagnetic spectra nonlinear dependence on the light signal intensity, the reflection properties of the system change significantly for chosen operation frequencies The photonic structure behavior with changing intensity is investigated for a few systems consisting of a periodically layered structure covered with an optically nonlinear material and a 3D opal PBG structure The latter plays the role of a motherboard controlling and directing the signals after the logical transformation Theoretical estimations of the adder cell parameters are made for Si/SiO/sub 2/ and GaAs/AlAs photonic crystals covered with layers made from nonlinear doped glasses The ideology of angular signal processing is developed It is shown that the angular-frequency diagram contains extremely sensitive areas inside the total reflection range, where the weak nonlinearity leads to dramatic change in light reflection and transmission Both solitary local modes and pure band modes are considered For 256-digit capacity the adder body has to consist of 32768 cells connecting by optical channels in the both schemes In summary, we discuss some general problems of "all-optical" signal processing, mechanisms of nonlinear signal transformation and the optical negative differential resistance areas existence, heating, energy losses and energy redistribution channels and geometry factors

Effects of nanostructure geometry on polymer chain alignment and device performance in nanoimprinted polymer solar cell

Abstract: Among the various organic photovoltaic devices, the conjugated polymer/fullerene approach has drawn the most research interest. The performance of these types of solar cells is greatly determined by the nanoscale morphology of the two components (donor/acceptor) and the molecular orientation/crystallinity in the photoactive layer. This article demonstrates our recent studies on the nanostructure geometry effects on the nanoimprint induced poly(3 hexylthiophene-2,5-diyl) (P3HT) chain alignment and photovoltaic performance. Out-of-plane and in-plane grazing incident X-ray diffractions are employed to characterize the chain orientations in P3HT nanogratings with different widths and heights . It is found that nanoimprint procedure changes the initial edge-on alignment in non-imprinted P3HT thin film to a vertical orientation which favors the hole transport, with an organization height H ≥ 170 nm and width in the range of 60 nm≤ W width w = 60 nm, height h = 170 nm), allowing for the most efficient charge separation, transport and light absorption. We believe this work will contribute to the optimal geometry design of nanoimprinted polymer solar cells.

Smart electroconductive textile by catalytic deposition of carbon nanotubes onto glass cloth

Abstract: Cobalt oxide nanoparticles were deposited on the surface of glass cloth by solution-combustion synthesis and used as a catalyst for the growth of carbon nanotubes via the CVD process. The structure and morphology of thus prepared smart glass cloth were characterized by XRD, TEM, and SEM. Thus prepared carbon nanotubes 23–26 nm in diameter exhibited good current–voltage characteristics. The heating efficiency of the flexible heating element at low temperature was tested on a soldier model. The smart glass cloth showed good electroconductive and effective Joule heating from external current source. The conductive glass cloth can be recommended for use in various functional applications.

Electric Field Effect in Atomically Thin Carbon Films

Abstract: We describe monocrystalline graphitic films, which are a few atoms thick but are nonetheless stable under ambient conditions, metallic, and of remarkably high quality. The films are found to be a two-dimensional semimetal with a tiny overlap between valence and conductance bands, and they exhibit a strong ambipolar electric field effect such that electrons and holes in concentrations up to 10 13 per square centimeter and with room-temperature mobilities of ∼10,000 square centimeters per volt-second can be induced by applying gate voltage.

疟原虫var基因转换速率变化导致抗原变异[英]／Paul H, Robert P, Christodoulou Z, et al//Proc Natl Acad Sci U S A

Abstract: 抗原变异可使得多种致病微生物易于逃避宿主免疫应答。表达在感染红细胞表面的恶性疟原虫红细胞表面蛋白1（PfPMP1）与感染红细胞、内皮细胞、树突状细胞以及胎盘的单个或多个受体作用，在黏附及免疫逃避中起关键的作用。每个单倍体基因组var基因家族编码约60种成员，通过启动转录不同的var基因变异体为抗原变异提供了分子基础。

Carbon Nanotubes--the Route Toward Applications

Abstract: Many potential applications have been proposed for carbon nanotubes, including conductive and high-strength composites; energy storage and energy conversion devices; sensors; field emission displays and radiation sources; hydrogen storage media; and nanometer-sized semiconductor devices, probes, and interconnects. Some of these applications are now realized in products. Others are demonstrated in early to advanced devices, and one, hydrogen storage, is clouded by controversy. Nanotube cost, polydispersity in nanotube type, and limitations in processing and assembly methods are important barriers for some applications of single-walled nanotubes.