Germanium nanocrystals embedded in silicon dioxide for floating gate memory devices

Metal-oxide-semiconductor (MOS) capacitors with tri-layer structure consisting of rf magnetron sputtered grown germanium (Ge) nanocrystals (NCs) and silicon dioxide (SiO2) layers sandwiched between thermally grown tunnel and sputtered grown cap oxide layers of SiO2 were fabricated on p-Si substrates. Plane view transmission electron micrographs revealed the formation of spherically shaped and uniformly distributed Ge NCs. The optical and electronic characteristics of tri-layer structures were studied through photoluminescence (PL) spectroscopy and capacitance-voltage (C-V) measurements, respectively. Frequency dependent electrical properties of the structures have been studied. The optical emission characteristics support the confinement of the carriers in Ge NCs embedded in oxide matrices. An anticlockwise hysteresis in C-V characteristics suggests electron injection and trapping in Ge NCs. When you are citing the document, use the following link http://essuir.sumdu.edu.ua/handle/123456789/2785

Germanium nanocrystals embedded in silicon dioxide for floating gate memory devices

Metal-oxide-semiconductor (MOS) capacitors with tri-layer structure consisting of rf magnetron sputtered grown germanium (Ge) nanocrystals (NCs) and silicon dioxide (SiO2) layers sandwiched between thermally grown tunnel and sputtered grown cap oxide layers of SiO2 were fabricated on p-Si substrates. Plane view transmission electron micrographs revealed the formation of spherically shaped and uniformly distributed Ge NCs. The optical and electronic characteristics of tri-layer structures were studied through photoluminescence (PL) spectroscopy and capacitance-voltage (C-V) measurements, respectively. Frequency dependent electrical properties of the structures have been studied. The optical emission characteristics support the confinement of the carriers in Ge NCs embedded in oxide matrices. An anticlockwise hysteresis in C-V characteristics suggests electron injection and trapping in Ge NCs. When you are citing the document, use the following link http://essuir.sumdu.edu.ua/handle/123456789/2785

Fluctuation-dissipation relationship in chaotic dynamics

We consider a general N-degree-of-freedom dissipative system which admits of chaotic behaviour. Based on a Fokker-Planck description associated with the dynamics we establish that the drift and the diffusion coefficients can be related through a set of stochastic parameters which characterize the steady state of the dynamical system in a way similar to fluctuation-dissipation relation in non-equilibrium statistical mechanics. The proposed relationship is verified by numerical experiments on a driven double well system.Comment: Revtex, 23 pages, 2 figure

Current status of arsenic contamination in drinkingwater and treatment practice in some rural areas of West Bengal, India

The aim of the present investigation was to draw the current scenario of arsenic (As) contamination in drinking water of community tube well and drinking water treated by tube wells installed with different adsorbent media-based treatment plants in districts Nadia, Hooghly and North 24-Parganas districts, West Bengal, India. As removal efficiencies of different treatment plants varied from 23 to 71%, which is largely governed by adsorption capacity of adsorbent and influencing environmental factors. Though investigated treatment plants removed substantial amount of As from tube well water, high As concentration in treated drinking water was retained after passing through the treatment plants. This high level of As concentration in tube well water and retention of high As concentration in treated drinking water were severe for the consumers which therefore, indicating the improvement of removal efficiency of treatment plant by meticulously considering favorable influencing factors or/and application of other high capacity treatment alternatives to adsorb the excess As retained in drinking water and regular monitoring of As concentration in the treated drinking water are indispensable

Analytical and numerical investigation of escape rate for a noise driven bath

We consider a system-reservoir model where the reservoir is modulated by an external noise. Both the internal noise of the reservoir and the external noise are stationary, Gaussian and are characterized by arbitrary decaying correlation functions. Based on a relation between the dissipation of the system and the response function of the reservoir driven by external noise we numerically examine the model using a full bistable potential to show that one can recover the turn-over features of the usual Kramers' dynamics when the external noise modulates the reservoir rather than the system directly. We derive the generalized Kramers' rate for this nonequilibrium open system. The theoretical results are verified by numerical simulation.Comment: Revtex, 25 pages, 5 figures. To appear in Phys. Rev.

Operator’s Fuzzy Norm and Some Properties

In this paper, a concept of operator’s fuzzy norm is introduced for the first time in general t-norm setting. Ideas of fuzzy continuous operators, fuzzy bounded linear operators are given with some properties of such operators studied in this general setting

Efficient rooting of microshoots of tea : a crucial prerequisite for successful hardening and field establishment of micropropagated plants

The application of tissue culture techniques for rapid and clonal mass propagation and improvement of tea is well known. While several laboratories have successfully developed in vitro propagation protocols, the use of this technology for mass multiplication of tea at commercial level is still limited largely due to difficulty in the quality of rooting of microshoots, and problems associated with subsequent hardening and field establishment. The present study reports a reproducible protocol for 100% rooting of in vitro propagated tea microshoots using a two-step method. This involves culture of microshoots on IBA (indole-3-butyric acid; 175.0 pM) containing Murashige and Skoog (1962; MS) medium for 10 days followed by transfer to 113 strength MS medium without any plant growth regulator. Besides the concentration of IBA, the period of exposure of microshoots to IBA containing medium (prior to transfer to PGR-free medium) also played a significant role in rooting. In addition, the culture temperature was found to be quite important; for maximum rooting response the optimum temperature range was 25-30°C.This item was scanned with a HP 4850 Scanjet at 300 dpi and consists of 7 pages

Seasonal distribution of cadmium among components of sewage treatment ponds: an eco-tech for heavy metal remediation

The study was designed to quantify cadmium accumulation in different components of sewage treatment ponds during different seasons and to assess risk for human consumption perspective. The study estimated cadmium concentration in water, sludge, Eichhornia, plankton and tilapia fish from anaerobic, facultative, maturation-1 and -4 ponds during pre-monsoon, monsoon and post-monsoon periods. It resulted that cadmium accumulated among different components of anaerobic, facultative, maturation-1 and -4 ponds ranging 0-18, 0-10, 0-7 and 0-15.4 ppb, respectively. During monsoon, highest accumulation was observed in tilapia in both facultative and maturation ponds, but during post-monsoon, plankton community showed highest value in all. The highest bio-magnification of cadmium was recorded during monsoon with varying degrees (facultative pond: 4.39, maturation pond-1: 3.03 and maturation pond-4: 7.08). Cadmium concentration in tilapia lied within WHO's safe level and may be recommended for human consumption. The concentration of cadmium was estimated by Flame Atomic Absorption Spectrophotometer. The above findings occurred due to chelation, adsorption and sedimentation, absorption and bio-accumulation, ionization, leaching through sediment and rainfall. Water pH (6.7-8.8), dissolved oxygen (0-17 mg L-1), total solids (251-650 mg L-1), iron (Fe2+) concentration (0.61-4.87 mg L-1) and sedimentation rate (278.9-2,409.6 g day-1 m-3) were conducive for the distribution of cadmium into different ecosystem components of treatment ponds. These ponds reclaimed 28.57-61.11 % of sewage-cadmium and may be promoted as a low-cost eco-tech for sewage treatment