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用于提高分辨能力的图象采集与处理

光电工程 1984年第6期 59-70页

作者： W.Thomas Cathey b.roy Frieden 毕平真

古典的提高光学分辨率的方法包括:或是适当的成象系统的设计,或是对已经形成的图象进行某种事后处理。本文的结果暗示我们:如果图象采集系统的设计是专门用来提高所采用的图象复原算法的性能的话,则可能得到一改进的图象。我们研究的是... 详细信息

古典的提高光学分辨率的方法包括:或是适当的成象系统的设计,或是对已经形成的图象进行某种事后处理。本文的结果暗示我们:如果图象采集系统的设计是专门用来提高所采用的图象复原算法的性能的话,则可能得到一改进的图象。我们研究的是这样一类问题:其中总的有效空间带宽是固定的,但该带宽沿空间频率轴的位置在某种程

关键词：成象系统成像系统图象采集图象复原点扩散函数点光源照明光源光瞳函数空间滤波器图象采集系统低通滤波器带通滤波器空间频率分辨能力

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蜘蛛丝的基础和应用研究概况

蚕桑通报 2009年第3期40卷 1-5页

作者：杨华军王丹李兴华 b.roy 缪云根浙江大学动物科学学院浙江杭州310029

本文简述了蜘蛛丝的种类、化学组成及基因表达等概况,介绍了蜘蛛丝的性能、基因研究和蜘蛛丝的应用研究及前景,重点介绍了利用哺乳动物、微生物、植物及转基因家蚕生产蜘蛛丝的方法。

关键词：蜘蛛丝转基因家蚕应用

RNA干扰技术和家蚕杆状病毒表达系统在纤维素酶研究中的应用前景

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蚕桑通报 2009年第2期40卷 5-10页

作者：李兴华杨华军 b.roy E.Y.Park 江丽军王丹缪云根浙江大学动物科学学院浙江杭州310029 日本静冈大学农学部应用生化系

植物通过光合作用产生的纤维素是地球上最丰富、最廉价的可再生资源。纤维素酶是糖苷水解酶的一种,能有效地将农作物秸杆等富含纤维素的物质水解为葡萄糖,进而发酵产生生物乙醇,从而解决农业、再生能源以及环境污染等问题。随着生物化... 详细信息

植物通过光合作用产生的纤维素是地球上最丰富、最廉价的可再生资源。纤维素酶是糖苷水解酶的一种,能有效地将农作物秸杆等富含纤维素的物质水解为葡萄糖,进而发酵产生生物乙醇,从而解决农业、再生能源以及环境污染等问题。随着生物化学、分子生物学以及基因工程等多种交叉学科的快速发展,获得适合工业化的高活力的纤维素酶指日可待。RNA干扰是利用双链RNA特异性地降解相应序列的mRNA,从而特异性地阻断相应基因的表达,是后基因组时代的一种强有力的调控目的基因表达的实验工具。家蚕杆状病毒表达系统是一种快速、高效表达外源基因的技术手段,目前该系统的发展和应用已经非常成熟。本文综述了纤维素酶的特性以及近年来国内外对纤维素酶、RNA干扰和家蚕杆状病毒表达系统的研究进展,并对该两种实验技术手段在今后纤维素酶研究中的应用前景作了预测和展望。

关键词：纤维素酶 RNA干扰家蚕杆状病毒表达系统

Treatment of recurrent Clostridium difficile colitis:a narrative review

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Gastroenterology Report 2018年第1期6卷 21-28,I0001页

作者： roy J.Hopkins Robert b.Wilson Department of Upper GI Surgery Liverpool HospitalSydneyNew South WalesAustralia

Clostridium difficile is a gram-positive,spore-forming,obligate anaerobic bacillus that was originally isolated from the stool of a healthy neonate in *** high-income countries,*** is the most common cause of infectious diarrhoea in hospitalized *** incidence of *** infection in the USA has increased markedly since 2000,with hospitalizations for *** infections in non-pregnant adults doubling between 2000 and *** 20%and 35%of patients with *** infection will fail initial antibiotic treatment and,of these,40–60%will have a second *** of *** infection after initial treatment causes substantial morbidity and is a major burden on health care *** this article,current treatments for recurrent *** infection are reviewed and future directions *** include the use of antibiotics,probiotics,donor faecal transplants,anion resins,secondary bile acids or anti-toxin antibodies.

关键词： Clostridium difficile recurrent infection faecal microbiota transplant anion-binding resins monoclonal antibodies secondary bile acid

Hydrodynamic dispersion of reactive solute in a Hagen–Poiseuille flow of a layered liquid

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Chinese Journal of Chemical Engineering 2017年第7期25卷 862-873页

作者： Sudip Debnath Apu Kumar Saha b.S.Mazumder Ashis Kumar roy Department of Mathematics National Institute of TechnologyAgartala 799046India Fluvial Mechanics Laboratory Physics and Applied Mathematics UnitIndian Statistical InstituteKolkata 700108India Fluid Mechanics and Hydraulic Laboratory(FMHL) Department of Aernspace Engineering and Applied MechanicsIndian Institute of Engineering Science and Technology(IIEST)ShibpurHowrah 711103India

An analysis of the solute dispersion in the liquid flowing through a pipe by means of Aris–barton's ‘method of moments', under the joint effect of some finite yield stress and irreversible absorption into the wall is presented in this paper. The liquid is considered as a three-layer liquid where the center region is Casson liquid surrounded by Newtonian liquid layer. A significant change from previous modelling exercises in the study of hydrodynamic dispersion, different molecular diffusivity has been considered for the different region yet to be constant. For all time period, finite difference implicit scheme has been adopted to solve the integral moment equation arising from the unsteady convective diffusion equation. The purpose of the study is to find the dependency of solute transport coefficients on absorption parameter, yield stress, viscosity ratio, peripheral layer variation and in addition with various diffusivity coefficients in different liquid layers. This kind of study may be useful for understanding the dispersion process in the blood flow analysis.

关键词： Casson liquid Yield stress Axial-dispersion coefficient Irreversible reaction Diffusivity

Structural,optical,electrical,and dielectric relaxation properties of rare earth containing sodium bismuth titanate Na_(0.5)bi_(0.5)TiO_(3) perovskite:Effect of ionic radius

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Journal of Rare Earths 2024年第2期42卷 383-391,I0006页

作者： Rajdip roy Abhigyan Dutta Department of Physics The University of BurdwanBurdwan713104India

The main focus of this work is to study the effect of the ionic radius of different rare earth dopant cations RE^(3+)(RE=La,Sm,Dy,and Ho) on structural and various physical properties of sodium bismuth titanate(Na_(0.5)b_(0.5)TiO_(3),NbT) based perovskite *** X-ray diffraction data indicate the successful formation of the rhombohedral phase(space group R3c) of NbT nano perovskite incorporated with various rare earth ions in *** lattice parameters were found to increase linearly with the ionic radius of the dopant *** ionic radii and atomic mass of rare earth dopants appear to be essential factors in the grain growth of the prepared *** grain growth results in better crystallinity of the sample by reducing the microstrain with the increase of dopant ionic *** emission scanning electron microscopy and energy-dispersive X-ray spectra confirm the prepared compositions' phase purity and *** UV-Vis spectra reveal that La-doped NbT composition exhibits the lowest optical band gap,which unfolds the application of NbT-based perovskite as photoactive *** ac conductivity and complex impedance spectra unveil that the composition with the largest ionic radius,i.e.,La-doped NbT compound,exhibits the highest dc and bulk conductivity with the lowest activation *** frequency-dependent dielectric data follows Havriliak-Negami(HN) formalism and non-Debye type relaxation *** also indicate that La-doped NbT composition exhibits the highest dielectric strength ***,this study first elaborates that the increasing ionic radius of the rare earth dopant cation in the bi-site of NbT perovskite improves its microstructural,optical,and electrical properties.

关键词： Rare earth doped NbT Microstructural analysis Optical band gap AC Conductivity Dielectric relaxation Rare earths

Effect of promoters on dynamics of gas-solid fluidized bed——Statistical and ANN approaches

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China Particuology 2007年第6期5卷 401-407页

作者： Y.K. Mohanty K.C. biswal G.K. roy b.P. Mohanty Department of Chemical Engineering GIET Gunupur 765 022 Rayagada Orissa India Department of Chemical Engineering NIT Rourkela 769008 Orissa India

In this study, a bubbling fluidized bed column, 99 mm in inside diameter and 960 mm in height, was used to investigate the effect of rod and disc promoters on fluctuation and expansion ratios. Factorial design （statistical approach） and artificial neural network （ANN） models were developed to predict the fluctuation and expansion ratios in this gas-solid fluidized bed with varying gas flow rates, bed heights, particle sizes and densities. The fluctuation and expansion predicted using these statistical and ANN models, for beds with and without promoters, were found to agree well with corresponding experiments. The statistical model was found to be superior to the ANN model due to its ability to take into account both individual and interactive effects. The rod promoters were found to be more effective in reducing bed fluctuation, and in increasing bed expansion at high gas mass velocities.

关键词： Gas-solid fluidized bed Fluctuation ratio Expansion ratio Promoter Factorial design Artificial neural network

Kinetics of thermal decomposition of hydrated minerals associated with hematite ore in a fluidized bed reactor

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International Journal of Minerals,Metallurgy and Materials 2017年第3期24卷 229-239页

作者： P.C. beuria S.K. biswal b.K. Mishra G.G. roy Institute of Minerals and Materials Technology Council of Scientific & Industrial Research Bhubaneswar-751013 India Indian Institute of Technology Kharagpur-721302 India

The kinetics of removal of loss on ignition(LOI) by thermal decomposition of hydrated minerals present in natural iron ores(i.e.,kaolinite,gibbsite,and goethite) was investigated in a laboratory-scale vertical fluidized bed reactor(FbR) using isothermal methods of kinetic *** in the FbR in batch processes were carried out at different temperatures(300 to 1200°C) and residence time(1 to 30 min) for four different iron ore samples with various LOIs(2.34wt% to 9.83wt%).The operating velocity was maintained in the range from 1.2 to 1.4 times the minimum fluidization velocity(Umf).We observed that,below a certain critical temperature,the FbR did not effectively reduce the LOI to a desired level even with increased residence *** results of this study indicate that the LOI level could be reduced by 90% within 1 min of residence time at 1100°*** kinetics for low-LOI samples(by a lower activation energy(diffusion-controlled physical moisture removal),followed by a higher activation energy(chemically controlled removal of LOI).In the case of high-LOI samples,three different kinetics mechanisms prevail at different temperature *** temperature up to 450°C,diffusion kinetics prevails(removal of physical moisture);at temperature from 450 to 650°C,chemical kinetics dominates during removal of matrix *** temperatures greater than 650°C,nucleation and growth begins to influence the rate of removal of LOI.

关键词： thermal decomposition fluidized beds kinetic analysis hydrated iron ore activation energy

Study on kinetics of thermal decomposition of low LOI goethetic hematite iron ore

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International Journal of Mining Science and Technology 2017年第6期27卷 1031-1036页

作者： beuria P.C. biswal S.K. Mishra b.K. roy G.G. Mineral Processing Department CSIR–Institute of Minerals and Materials TechnologyBhubaneswar 751013India Indian Institute of Technology Kharagpur 721302India

In the present study, the kinetics of thermal decomposition of hydrated minerals associated in natural hematite iron ores has been investigated in a fixed bed system using isothermal methods of kinetic analysis. Hydrated minerals in these hematite iron ores are kaolinite, gibbsite and goethite, which contribute to the loss on ignition(LOI) during thermal decomposition. Experiments in fixed bed have been carried out at variable bed depth(16, 32, 48 and 64 mm),temperature(400-1200 ℃) and residence time(30,45, 60 and 75 min) for iron ore samples. It is observed that beyond a certain critical bed depth(16 mm), 100% removal of LOI is not found possible even at higher temperature and higher residence time. Most of the solid-state reactions of isothermal kinetic analysis have been used to analyze the reaction mechanism. The raw data are modified to yield fraction reacted "α" versus time and used for developing various forms of "α" functions.f(α) is the inverse of first derivative of g(α) with respect to α. The study demonstrates that decomposition of hydrated mineral in hematite follows the chemical *** estimated activation energy values in all the experimental situations are found to high, of the order of 60 kJ/mol, reinstating that the reactions are indeed controlled by moving phase boundary and random nucleation.

关键词： Loss on ignition Goethite Kaolinite Gibbsite Roasting Pellet feed Kinetic analysis