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121.
P. Chakraborty S.S. Mahato M.K. Bera S.K. Samanta C.K. Maiti 《Microelectronic Engineering》2009,86(3):299-302
Potential of high-k dielectric films for future scaled charge storage non-volatile memory (NVM) device applications is discussed. To overcome the problems of charge loss encountered in conventional flash memories with silicon-nitride (Si3N4) films and polysilicon-oxide-nitride-oxide-silicon (SONOS) and nonuniformity issues in nanocrystal memories (NC), such as Si, Ge and metal, it is shown that the use of high-k dielectrics allows more aggressive scaling of the tunnel dielectric, smaller operating voltage, better endurance, and faster program/erase speeds. Charge-trapping characteristics of high-k AlN films with SiO2 as a blocking oxide in p-Si/SiO2/AlN/SiO2/poly-silicon (SOHOS) memory structures have been investigated in detail. The experimental results of program/erase characteristics obtained as the functions of gate bias voltage and pulse width are presented. 相似文献
122.
Piyas Samanta Chin-Lung Cheng Yao-Jen Lee Mansun Chan 《Microelectronic Engineering》2009,86(7-9):1767-1770
We have investigated electrical stress-induced positive charge buildup in a hafnium aluminate (HfAlO)/silicon dioxide (SiO2) dielectric stack (equivalent oxide thickness = 2.63 nm) in metal–oxide–semiconductor (MOS) capacitor structures with negative bias on the TaN gate. Various mechanisms of positive charge generation in the dielectric have been theoretically studied. Although, anode hole injection (AHI) and valence band hole tunneling are energetically favorable in the stress voltage range studied, the measurement results can be best explained by the dispersive proton transport model. 相似文献
123.
Pinak Pani Biswas Rishi Srivastava Subhabrata Ray Amar Nath Samanta 《Mechatronics》2009,19(4):548-561
The process investigated herein is the quadruple tank system that is stable only within a limited zone of operating parameters. The process model has been developed from fundamentals and tuned with experimental data. A controller design based on feedback linearization has been tested on this process model. Coupling feedback linearization with sliding mode algorithm provides robust control of the process and performs far superior to conventional PI control. A PC based controller interfaced to the experimental quadruple tank experimental set up has been used to implement this algorithm and test its performance. Inserting a ‘boundary layer’ around the sliding surface reduced the ‘chattering’ associated with sliding mode control. The implemented controller provides robust control and excellent set point tracking. 相似文献
124.
A new method is proposed to implement an optical S-R flip-flop by polarization encoded light signal,necessary optical nonlinear material and half-wave plate.In this system the real time speed of operation can be achieved,and at the time of transmission the average power of a byte remains constant.This polarization encoded flip-flop can act as a memory cell. 相似文献
125.
Patra A Hebalkar N Sreedhar B Sarkar M Samanta A Radhakrishnan TP 《Small (Weinheim an der Bergstrasse, Germany)》2006,2(5):650-659
Intermolecular interactions, such as hydrogen bonding, dipolar and van der Waals, occurring in molecular crystals cover a range of magnitudes. As the crystal evolves from a relatively softer state in the nanoscopic size regime to a harder one in the microcrystalline and bulk solid state, the impact of the hierarchy of intermolecular interactions can be expected to emerge in a progressive fashion. The strongest interactions alone would be manifested at small sizes; as the crystal grows, the effect of the weaker ones will be added on, with the bulk crystals exhibiting the cumulative impact of the different interactions. We demonstrate this phenomenon through investigations of the solution, colloid, and solid state of a novel zwitterionic molecule based on the diaminodicyanoquinodimethane framework. A reprecipitation-digestion protocol is developed for the fabrication of nano/microcrystals of varying sizes. Microscopic and spectroscopic characterizations reveal tuning of the size and optical properties of this material. The optical absorption of the colloidal particles evolves with size towards that of the bulk solid, the emission showing a steady enhancement of intensity. Crystallographic investigations coupled with semiempirical computations provide a viable model to describe the range of observations in terms of the gradual accumulation of hierarchical intermolecular interactions. 相似文献
126.
Nano-Micro Letters - The resistive switching memory characteristics of 100 randomly measured devices were observed by reducing device size in a Cr/CrO x /TiO x /TiN structure for the first time.... 相似文献
127.
128.
Samanta Thomas-Valdés Maria das Graças V. Tostes Bárbara P. da Silva Helena M. Pinheiro Sant'Ana 《Critical reviews in food science and nutrition》2017,57(15):3332-3343
Inappropriate food behavior contributes to obesity and leads to vitamin deficiency. This review discusses the nutritional status of water- and fat-soluble vitamins in obese subjects. We verified that most vitamins are deficient in obese individuals, especially the fat-soluble vitamins, folic acid, vitamin B12 and vitamin C. However, some vitamins have been less evaluated in cases of obesity. The adipose tissue is considered a metabolic and endocrine organ, which in excess leads to changes in body homeostasis, as well as vitamin deficiency which can aggravate the pathological state. Therefore, the evaluation of vitamin status is of fundamental importance in obese individuals. 相似文献
129.
J Anguita SW Barthold S Samanta J Ryan E Fikrig 《Canadian Metallurgical Quarterly》1999,179(3):734-737
The role of interleukin (IL)-11, a cytokine with potent anti-inflammatory properties, in murine Lyme disease was investigated. Borrelia burgdorferi-infected mice treated with IL-11 developed less arthritis than did control animals. In contrast, IL-11 blocking antibodies increased Lyme arthritis. Murine Lyme carditis was not affected by either IL-11 or IL-11 antibodies. Administration of IL-11 was associated with increased production of mRNA for IL-12 and inducible nitric oxide synthase but not interferon-gamma or IL-4 in B. burgdorferi-infected mice, suggesting a predominant effect of IL-11 on the innate immune response. These data show that IL-11 selectively reduced joint but not cardiac inflammation caused by B. burgdorferi in mice. 相似文献
130.
Gold and Hairpin DNA Functionalization of Upconversion Nanocrystals for Imaging and In Vivo Drug Delivery
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