ANAS

About: ANAS is a based out in . It is known for research contribution in the topics: Crystal structure & Liquidus. The organization has 661 authors who have published 580 publications receiving 3868 citations. The organization is also known as: Azienda Nazionale Autonoma delle Strade.

Effective Nonlinear GaSe Crystal. Optical Properties and Applications

Abstract: We present an overview of the current state of the literature and research performed by the authors of the present paper on the experimental and theoretical results on the structural-, optical-, nonlinear optical (NLO)-properties (including two-photon absorption (TPA) and the terahertz (THz) range of spectra) and practical applications of a highly anisotropic Gallium Selenide (GaSe) semiconductor with emphasis on the ɛ-GaSe Physical properties of ɛ-GaSe are important to researchers and designers developing different devices by using this material This crystal possesses an outstanding NLO properties: high optical birefringence Δn ∼ 03 at 700 nm; high transparency range (07−180 μm) with low absorption coefficient (α ≤ 03 cm−1); very high nonlinear susceptibility χ(2) (d 22 ≈ 86 ± 17 pm/V, corresponding to (20 ± 04) × 10−7 esu) that is used for phase matched second harmonic generation (SHG) in a wide transparency range; high power threshold for optical damage; possibility to perform optical frequency conversion under phase-matching conditions in the near- to mid-IR and THz range of spectra, etc The domain structure of crystal in connection with the NLO properties is discussed as studied by confocal Raman microscopy experiments Perspectives for future research of GaSe are considered in the present article, which does not pretend to be one reflecting all existing papers on GaSe crystal and discussed subjects

Identification of Promoter Regions and Regulatory Sites

Abstract: Promoter sequences are the main regulatory elements of gene expression. Their recognition by computer algorithms is fundamental for understanding gene expression patterns, cell specificity and development. This chapter describes the advanced approaches to identify promoters in animal, plant and bacterial sequences. Also, we discuss an approach to identify statistically significant regulatory motifs in genomic sequences.

Size-induced effects in gallium selenide electronic structure: The influence of interlayer interactions

Abstract: The electronic structure of two-dimensional gallium selenide crystals containing a small number of layers was investigated theoretically and experimentally. The electronic band structure of the layered GaSe crystal was investigated by the first-principles density functional theory calculations. The $GW$ approximation was used for the correction of the band-gap values. A dependence of the band-gap value on the number of tetralayers has been demonstrated. For the thin crystal with several tetralayers, the band gap becomes larger compared to the bulk crystal. The thin layers of GaSe have been experimentally produced by the ultrasonication of GaSe particles in water suspensions in the presence of Pluronic F127 surfactant. Their thickness was from one to a few tetralayers, according to the transmission electron microscopy studies. The optical absorption spectra demonstrate the well-resolved bands, shifted toward the blue relative to those of the bulk GaSe. Their origin is caused by the presence of GaSe structures with one to a few tetralayers.

Pay-for-results based marketing

Abstract: A method of acquiring customers via a computer network includes receiving user input relating to a desired product. Then, a preferred product(s) is automatically determined from a plurality of products as a function of the user input. After the user performs an activity with a vendor, a payment is received from the vendor.