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Formation of High-quality Advanced High-k Oxide Layers at Low temperature by Excimer UV Lamp-assisted Photo-CVD and Sol-gel Processing

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Chemical Research in Chinese Universities 2004年第4期20卷 396-402页

作者： YU j. j. Electronic & Electrical Engineering University College London

We have successfully demonstrated that high quality and high dielectric constant layers can be fabricated by low temperature photo-induced or -assisted processing. ta_2O_5 and ZrO_2 have been deposited at tto-CVD technique and HfO_2 by photo-assisted sol-gel processing with the aid of excimer lamps. the UV annealing of as-grown layers was found to significantly improve their electrical properties. Low leakage current densities on the order of 10 -8 A/cm 2 at 1 MV/cm for deposited ultrathin ta_2O_5 films and ca.10 -6 A/cm 2 for the photo-CVD ZrO_2 layers and photo-irradiated sol-gel HfO_2 layers have been readily achieved. the improvement in the leakage properties of these layers is attributed to the UV-generated active oxygen species O( 1D) which strongly oxidize any suboxides to form more stoichiometric oxides on removing certain defects, oxygen vacancies and impurities present in the as-prepared layers. the photo-CVD ta_2O_5 films deposited across 10.16-cm Si wafers exhibit a high thickness uniformity with a variation of less than \{±2.0%\} being obtained for ultrathin ca.10 nm thick films. the lamp technology can in principle be extended to larger area wafers, providing a promising low temperature route to the fabrication of a range of high quality thin films for future ULSI technology.

关键词： Excimer lamp High-kdielectrics thin film Chemical vapour deposition(CVD) Sol-gel processing

Biodegradation of alkylates under less agitated aquifer conditions

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j.urnal of Environmental Sciences 2013年第8期25卷 1529-1538页

作者： j.y j. Cho Makram t. Suidan Albert D. Venosa URS Corporation 7720N 16th st. ste 100 Phoenix AZ 85020 USA Faculty of Engineering and Architecture American University of Beirut Dean's officeP.O.Box 11-0236 Riad El Solh 1107 2020 Beirut Lebanon US Environmental Protection Agency National Risk Management Research LaboratoryCincinnati OH 45268 USA

the biodegradability of three alkylates （2,3-dimethylpentane, 2,4-dimethylpentane and 2,2,4-trimethylpentane） under less agitated aquifer conditions was investigated in this study. All three alkylates biodegraded completely under these conditions regardless of the presence or absence of ethanol or benzene, toluene, ethylbenzene, and xylenes （BtEX） in the feed. In the presence of ethanol, alkylates degradation was not inhibited by ethanol. However, alkylates degraded more slowly in the presence of BtEX suggesting competitive inhibition to microbial utilization of alkylates. In the sterile controls, alkylates concentrations remained unchanged throughout the experiments.

关键词： biodegradation alkylates inhibition BtEX ethanol

Nonlocal-Means Image Denoising technique Using Robust M-Estimator

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j.urnal of Computer Science & technology 2010年第3期25卷 623-631页

作者： Dinesh j. Peter V. K. Govindan Abraham t. Mathew Department of Computer Science National Institute of Technology Calicut Department of Electrical Engineering National Institute of Technology Calicut

Edge preserved smoothing techniques have gained importance for the purpose of image processing applications A good edge preserving filter is given by nonlocal-means filter rather than any other linear model based approaches. this paper explores a different approach of nonlocal-means filter by using robust M-estimator function rather than the exponential function for its weight calculation. Here the filter output at each pixel is the weighted average of pixels with surrounding neighborhoods using the chosen robust M-estimator function. the main direction of this paper is to identify the best robust M-estimator function for nonlocal-means denoising algorithm. In order to speed up the computation, a new patch classification method is followed to eliminate the uncorrelated patches from the weighted averaging process. this patch classification approach compares favorably to existing techniques in respect of quality versus computational time. Validations using standard test images and brain atlas images have been analyzed and the results were compared with the other known methods. It is seen that there is reason to believe that the proposed refined technique has some notable points.

关键词： image processing denoising technique nonlocal-means filter robust M-estimators

Differences in Physiological Age Affect Diagnosis of Nitrogen Deficiencies in Cornfields

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Pedosphere 2008年第5期18卷 545-553页

作者： j. ZHANG A. M. BLACKMER t. M. BLACKMER statistical Consulting Center Wright State University 3640 Colonel Glenn Highway Dayton Ohio 45435 （USA）. Department of Agronomy Iowa State University Ames Iowa 50011 （USA） Iowa Soybean Association 4554 114th Street Urbandale Iowa 50322 （USA）

Many studies have shown that chlorophyll meter readings （CMRs） can be used to diagnose deficiencies of nitrogen （N） during the growth of corn （Zea mays L.） in small-plot trials, but there is need to address additional problems encountered when diagnoses are made in fields of the size managed in production agriculture. A noteworthy difference between smallplot trials and production agriculture is the extent to which the effects of N are confounded with the effects of other factors such as tillage, landscape, soil organic matter and moisture content. We illustrate how some of these factors can cause differences in the physiological age of plants and introduce errors in the diagnoses of N deficiencies. We suggest methods （measuring the height to the youngest leaf collar and assigning leaf numbers by using the first leaf with pubescence and the ear leaf as references to identify growth stages） for minimizing these errors. the simplified method of growth stage identification can be used to select appropriate plants and leaves for making diagnoses in fields and to distinguish the effects of N from the effects of other factors that influence plant growth.

关键词： chlorophyll corn (Zea mays L.) nitrogen deficiency physiological age

Sampling Size Required for Determining Soil Carbon and Nitrogen Properties at Early Establishment of Second Rotation Hoop Pine Plantations in Subtropical Australia

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Pedosphere 2007年第6期17卷 706-711页

作者： t. j. BLUMFIELD XU Zhi-Hong N.V. PRASOLOVA Centre for Forestry and Horticultural Research Nathan Campus Griffith University 170 Kessels Road Nathan Queensland 4111 （Australia） Faculty of Science Griffth University Nathan Campus Griffth University 170 Kessels Road Nathan Queensland 4111 （Australia）

Investigations into forest soils face the problem of the high level of spatial variability that is an inherent property of all forest *** order to investigate the effect of changes in residue management practices on soil properties in hoop pine(Araucaria cunninghamii Aiton ex ***.)plantations of subtropical Australia it was important to understand the intensity of sampling effort required to overcome the spatial variability induced by those *** residues were formed into windrows to prevent nitrogen(N)losses through volatilisation and erosion that had previously occurred as a result of pile and burn *** selected second rotation(2R)hoop pine sites where the windrows(10-15 m apart)had been formed 1,2 and 3 years prior to sampling in order to examine the spatial variability in soil carbon(C) and N and in potential mineralisable N(PMN)in the areas beneath and between(inter-)the *** examined the implications of soil variability on the number of samples required to detect differences in means for specific soil properties, at different ages and at specified levels of *** size needed to accurately reflect differences between means was not affected by the position where the samples were taken relative to the windrows but differed according to the parameter to be *** relative soil sampling size required for detecting differences between means of a soil property in the inter-windrow and beneath-windrow positions was highly dependent on the soil property assessed and the acceptable relative sampling *** alternative strategy for soil sampling should be considered,if the estimated sample size exceeds 50 *** possible solution to this problem is collection of composite soil samples allowing a substantial reduction in the number of samples required for chemical analysis without loss in the precision of the mean estimates for a particular soil property.

关键词： hoop pine nitrogen potential mineralisable nitrogen residue management soil spatial variability

Synthesis and dissociation of soliton molecules in parallel optical-soliton reactors

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Light(Science & Applications) 2021年第7期10卷 1289-1303页

作者： Wenbin He Meng Pang Dung-Han Yeh j.apeng Huang Philip.st.j.Russell Max Planck Institute for the Science of Light staudtstrasse 2 91058 ErlangenGermany Department of Physics Friedrich-Alexander-UniversitätStaudtstrasse 291058 ErlangenGermany state Key Laboratory of High Field Laser Physics Shanghai Institute of Optics and Fine MechanicsChinese Academy of SciencesShanghai 201800China

Mode-locked lasers have been widely used to explore interactions between optical solitons,including bound-soliton states that may be regarded as“photonic molecules”.Conventional mode-locked lasers normally,however,host at most only a few solitons,which means that stochastic behaviours involving large numbers of solitons cannot easily be studied under controlled experimental *** we report the use of an optoacoustically mode-locked fibre laser to create hundreds of temporal traps or“reactors”in parallel,within each of which multiple solitons can be isolated and controlled both globally and individually using all-optical *** achieve on-demand synthesis and dissociation of soliton molecules within these reactors,in this way unfolding a novel panorama of diverse dynamics in which the statistics of multi-soliton interactions can be *** results are of crucial importance in understanding dynamical soliton interactions and may motivate potential applications for all-optical control of ultrafast light fields in optical resonators.

关键词： optical soliton solitons

Point-based tool representations for modeling complex tool shapes and runout for the simulation of process forces and chatter vibrations

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Advances in Manufacturing 2018年第3期6卷 301-307页

作者： P. Wiederkehr t. Siebrecht j. Baumann D. Biermann Institute of Machining technology TU Dortmund University Dortmund Germany Virtual Machining Department of Computer Science TU Dortmund University Dortmund Germany

Geometric physically-based simulation systemscan be used for analyzing and optimizing complex millingprocesses, for example in the automotive or aerospaceindustry, where the surface quality and process efficiencyare limited due to chatter vibrations. Process simulationsusing tool models based on the constructive solid geometry（CSG） technique allow the analysis of process forces, tooldeflections, and surface location errors resulting from five-axis machining operations. However, modeling complextool shapes and effects like runout is difficult using CSGmodels due to the increasing complexity of the shapedescriptions. therefore, a point-based method for modelingthe rotating tool considering its deflections is presented inthis paper. With this method, tools with complex shapesand runout can be simulated in an efficient and flexibleway. the new modeling approach is applied to exemplarymilling processes and the simulation results are validatedbased on machining experiments.

关键词： Modeling tool geometry Milling

Preparation of open-tubular columns in electrochromatography with sol-gel technology

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Chinese Science Bulletin 1998年第9期43卷 790-791页

作者： t. Hevesi j. Krup?ík j. R. Chrétien Beij.ng Inst technol Dept Chem Engn Beijing 100081 Peoples R China

Corrections to the scaling of the second-order structure function in isotropic turbulence

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Acta Mechanica Sinica 2010年第2期26卷 151-157页

作者： Le Fang Wouter j. t. Bos Xiaozhou Zhou Liang Shao j.an-Pierre Bertoglio Laboratoire de Mecanique des Fluides et d'Acoustique Universit6 de Lyon Ecole centrale de Lyon 69134 Ecully France Department of Mechanical Engineering Center for Biomedical Engineering Research University of Delaware 126 Spencer Laboratory Newark DE 19716 USA

the approach of Obukhov assuming a constant skewness was used to obtain analytical corrections to the scaling of the second order structure function, starting from Kolmogorov＇s 4/5 law. these corrections can be used in model applications in which explicit expressions, rather than numerical solutions are needed. the comparison with an interpolation formula proposed by Batchelor, showed that the latter gives surprisingly precise results. the modification of the same method to obtain analytical corrections to the scaling law, taking into account the possible corrections induced by intermittency, is also proposed.

关键词： Scaling law · structure function ·Isotropic turbulence