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261.
A single-electron memory, in which a bit of information is stored by one electron, is demonstrated at room temperature. The memory is a floating gate metal-oxide-semiconductor transistor in silicon with a channel width ( approximately 10 nanometers) smaller than the Debye screening length of a single electron and a nanoscale polysilicon dot ( approximately 7 nanometers by 7 nanometers) as the floating gate embedded between the channel and the control gate. Storing one electron on the floating gate screens the entire channel from the potential on the control gate and leads to (i) a discrete shift in the threshold voltage, (ii) a staircase relation between the charging voltage and the shift, and (iii) a self-limiting charging process. The structure and fabrication of the memory should be compatible with future ultralarge-scale integrated circuits. 相似文献
262.
Wu YC Su JH Chou TT Cheng YP Weng CF Lee CH Fang LS Wang WH Li JJ Lu MC Kuo J Sheu JH Sung PJ 《Marine drugs》2011,9(12):2773-2792
The structures, names, bioactivities, and references of 81 new secondary metabolites obtained from gorgonian corals belonging to the genus Junceella are described in this review. All compounds mentioned in this review were obtained from sea whip gorgonian corals Junceella fragilis and Junceella juncea, collected from the tropical and subtropical Indo-Pacific Ocean. 相似文献
263.
Muhammad Safwan Ahamad Bustamam Hamza Ahmed Pantami Awanis Azizan Khozirah Shaari Chong Chou Min Faridah Abas Norio Nagao Maulidiani Maulidiani Sanjoy Banerjee Fadzil Sulaiman Intan Safinar Ismail 《Marine drugs》2021,19(3)
This study was designed to profile the metabolites of Isochrysis galbana, an indigenous and less explored microalgae species. 1H Nuclear Magnetic Resonance (NMR) spectroscopy and Liquid Chromatography-Mass Spectrometry (LCMS) were used to establish the metabolite profiles of five different extracts of this microalga, which are hexane (Hex), ethyl acetate (EtOAc), absolute ethanol (EtOH), EtOH:water 1:1 (AqE), and 100% water (Aq). Partial least square discriminant analysis (PLS–DA) of the generated profiles revealed that EtOAc and Aq extracts contain a diverse range of metabolites as compared to the other extracts with a total of twenty-one metabolites, comprising carotenoids, polyunsaturated fatty acids, and amino acids, that were putatively identified from the NMR spectra. Meanwhile, thirty-two metabolites were successfully annotated from the LCMS/MS data, ten of which (palmitic acid, oleic acid, α-linolenic acid, arachidic acid, cholesterol, DHA, DPA, fucoxanthin, astaxanthin, and pheophytin) were similar to those present in the NMR profile. Another eleven glycerophospholipids were discovered using MS/MS-based molecular network (MN) platform. The results of this study, besides providing a better understanding of I. galbana’s chemical make-up, will be of importance in exploring this species potential as a feed ingredient in the aquaculture industry. 相似文献
264.