Excellent buffer layer for growing high-quality Y-Ba-Cu-O thin films

Eu2CuO4 (ECO) has been used as a buffer layer for growing of YBa2Cu3O7-ä (YBCO) thin films on SrTiO3(100) and Y-stabilized ZrO2(100) substrates. The epitaxy, crystallinity, and surface of YBCO thin films have been significantly improved by using ECO buffer layer as investigated by x-ray diffraction, rocking curves, scanning electron microscope, surface step profiler, and x-ray small-angle reflection. The best value of the full width at half-maximum of the YBCO(005) peak can be greatly reduced down to less than 0.1°. The scanning-electron-microscope photos indicate a very smooth surface for the YBCO thin films. The average roughness is less than 5 nm over a wide scanning region of 2000 ìm. The results of x-ray small-angle reflection indicate a very clear and flat interface between YBCO and ECO layers. Meanwhile, the resistivity of ECO is about 20 times higher than that of PrBa2Cu3Oy at the boiling point of liquid nitrogen. Our results suggest that ECO should be a good barrier candidate for fabricating high-Tc superconductor junctions.published_or_final_versio

Heterogeneous photodegradation of pentachlorophenol and iron cycling with goethite, hematite and oxalate under UVA illumination

2009-2010 > Academic research: refereed > Publication in refereed journalAccepted ManuscriptPublishe

Improved electrical properties of metal-oxide-semiconductor capacitor with HfTiON gate dielectric by using HfSiON interlayer

Metal-oxide-semiconductor (MOS) capacitor with HfTiONHfSiON stack structure as high- k gate dielectric is fabricated, and its electrical properties are compared with those of a similar device with HfTiON only as gate dielectric. Experimental results show that the device with HfTiONHfSiON gate dielectric exhibits better interface properties, lower gate leakage current, and enhanced high-field reliability. All these improvements should be attributed to the fact that the HfSiON buffer layer effectively blocks the diffusion of Ti atoms to the Si substrate, thus resulting in a Si O2 Si -like HfSiONSi interface. © 2007 American Institute of Physics.published_or_final_versio

Optimization of N content for higk-k LaTiON gate dielectric of Ge MOS capacitor

Thin LaTiON gate dielectric is deposited on Ge (100) substrate by reactive co-sputtering of La 2O 3 and Ti targets under different Ar/N 2 ratios of 24/3, 24/6, 24/12, and 24/18, and their electrical properties are investigated and compared. Results show that the LaTiON gate-dielectric Ge MOS capacitor prepared at an Ar/N 2 ratio of 24/6 exhibits highest relative permittivity, smallest capacitance equivalent thickness, and best electrical characteristics, including low interface-state density, small C-V hysteresis and low gate leakage current. This is attributed to the fact that a suitable N content in LaTiON can effectively suppress the growth of low-k GeO x interfacial layer between LaTiON and Ge substrate.published_or_final_versionThe IEEE International Conference of Electron Devices and Solid-State Circuits (EDSSC) 2009, Xi'an, China, 25-27 December 2009. In Proceedings of EDSSC, 2009, p. 225-22

Molecular cloning and characterization of a novel expressed sequence tag (EST) associated with fecundity in goats

To screen the genes controlling the fecundity traits in goats, a DDRT-PCR technique was applied. We found a new EST which highly expressed in Chinese native prolific goat breed, Haimen goats. There exists a difference of EST expression level between the prolific and non-prolific goat breed, indicating EST might associate to fecundity in goats. A full-length cDNA with 2253 base pairs was obtained by the 3’- and 5’-RACE method based on the EST sequence encoding a protein segment of 201 amino acid residues. Tissue specific distribution and sequence analysis implicated the likely involvement of EST in the regulation of the hormones related to fecundity

A computational cognition model of perception, memory, and judgment

The mechanism of human cognition and its computability provide an important theoretical foundation to intelligent computation of visual media. This paper focuses on the intelligent processing of massive data of visual media and its corresponding processes of perception, memory, and judgment in cognition. In particular, both the human cognitive mechanism and cognitive computability of visual media are investigated in this paper at the following three levels: neurophysiology, cognitive psychology, and computational modeling. A computational cognition model of Perception, Memory, and Judgment (PMJ model for short) is proposed, which consists of three stages and three pathways by integrating the cognitive mechanism and computability aspects in a unified framework. Finally, this paper illustrates the applications of the proposed PMJ model in five visual media research areas. As demonstrated by these applications, the PMJ model sheds some light on the intelligent processing of visual media, and it would be innovative for researchers to apply human cognitive mechanism to computer science.</p

Is It Time to Phase Out the Austin Moore Hemiarthroplasty? A Propensity Score Matched Case Control Comparison versus Cemented Hemiarthroplasty

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Eliminación de DBP en aceite de onagra mediante arcilla activada modificada por chitosán y CTAB

The pollution of phthalic acid esters (PAEs) in edible oils is a serious problem. In the current study, we attempt to remove dibutyl phthalate ester (DBP) from evening primrose oil (EPO) with modified activated clay. The activated clay, commonly used for de-coloration in the oil refining process, was modified by chitosan and hexadecyl trimethyl ammonium bromide (CTAB). The modifications were characterized by SEM, XRD, and FT-IR. We further tested the DBP adsorption capacity of CTAB/chitosan-clay and found that the removal rate was 27.56% which was 3.24 times higher than with pristine activated clay. In addition, the CTAB/chitosan-clay composite treatment had no significant effect on the quality of evening primrose oil. In summary, the CTAB/chitosan-clay composite has a stronger DBP adsorption capacity and can be used as a new adsorbent for removing DBP during the de-coloration process of evening primrose oil.La contaminación por ésteres de ácido ftálico (PAEs) en los aceites comestibles es un problema grave. En el presente estudio, intentamos eliminar el éster de ftalato de dibutilo (DBP) del aceite de onagra (EPO) con arcilla activada modificada. La arcilla activada, comúnmente utilizada en la decoloración en el proceso de refinación de los aceites, fue modificada con chitosán y bromuro de hexadecil trimetil amonio (CTAB). Las modificaciones se caracterizaron mediante SEM, XRD y FT-IR. Además, probamos la capacidad de adsorción de DBP de CTAB / chitosán-arcilla y descubrimos que la tasa de eliminación era del 27,56%, que era 3,24 veces mayor que la arcilla activada pura. Además, el tratamiento compuesto de CTAB/chitosán-arcilla no tuvo un efecto significativo sobre la calidad del aceite de onagra. En resumen, el compuesto CTAB/chitosán-arcilla tiene una capacidad de adsorción de DBP más fuerte y se puede utilizar como un nuevo adsorbente para eliminar DBP durante el proceso de decoloración del aceite de onagra

Enhanced Dielectric Constant for Efficient Electromagnetic Shielding Based on Carbon-Nanotube-Added Styrene Acrylic Emulsion Based Composite

An efficient electromagnetic shielding composite based on multiwalled carbon nanotubes (MWCNTs)-filled styrene acrylic emulsion-based polymer has been prepared in a water-based system. The MWCNTs were demonstrated to have an effect on the dielectric constants, which effectively enhance electromagnetic shielding efficiency (SE) of the composites. A low conductivity threshold of 0.23 wt% can be obtained. An EMI SE of ~28 dB was achieved for 20 wt% MWCNTs. The AC conductivity (σac) of the composites, deduced from imaginary permittivity, was used to estimate the SE of the composites in X band (8.2–12.4 GHz), showing a good agreement with the measured results

Effectiveness of additional follow-up telephone counseling in a smoking cessation clinic in Beijing and predictors of quitting among Chinese male smokers

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