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The integration of methanogenesis with denitrification and anaerobic ammonium oxidation in an expanded granular sludge bed reactor

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Journal of Environmental sciences 2003年第3期15卷 423-432页

作者： ZHANG Dai-jun 1.2.(1. Department of Environmental {1., Chongqing University, Campus A, Chongqing 400044, china 2. Key Laboratory for the Southwest china Resources Exploitation and Environmental Disaster Control Engineering, Ministry of Education, china.) Department of Environmental science Chongqing University China

The integration of methanogenesis with denitrification and anaerobic ammonium oxidation(ANAMMOX) was studied in an expanded granular sludge bed(EGSB) reactor in this work. Experimental results from the continuous treatment of wastewater with nitrite and ammonium, which lasted for 1.7 days, demonstrated that wastewater with high nitrite and ammonium could be anaerobically treated in an expanded granular sludge bed reactor. More than 91. to 97% of COD were removed at up to about 3.9 g COD/(L·d) of COD volumetric loading rate. More than 97% to 1.0% of nitrite was denitrified at up to about 0.8 g NO -_2.N/(L·d), which is 1. times higher than that in a conventional activated sludge system with nitrification/denitrification(0.05 gN/(L·d)). No dissimilatory reduction of nitrite to ammonium occurred in the process. However, maximum of about 40% ammonium was found to be lost. Batch tests of 1. days with sludge from the reactor showed that 1.0% of nitrite was denitrified completely, and about 3% of ammonium was removed when only ammonium (34.3 mg/L) and nitrite(34.3 mg/L) were added into the sludge suspension medium. Furthermore, about 1.% of ammonium amounts were lost with organic COD addition. It suggested that the methanogenesis in the system could enhance ANAMMOX because of intermediate hydrogen produced during methanogenesis.

关键词： methanogenesis denitrification ANAMMOX EGSB reactor

Numerical simulations of the bi-level and branched structure of intracloud lightning flashes

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science {1. Earth sciences 2006年第6期49卷 661-672页

作者： TAN Yongbo1. TAO Shanchang1. ZHU Baoyou1. MA Ming2.& LU Weitao2.1. school of Earth and Space sciences, University of science and Technology of china, Hefei 2.002., china 2. Chinese Academy of Meteorological sciences, Beijing 1.0081. china 1. school of Earth and Space {1.s University of Science and Technology of China Hefei 230026 China 2. Chinese Academy of Meteorological {1.s Beijing 100081 China

Intracloud (IC) lightning flashes have been simulated in fine resolution (1.0}5 m) by using a bidirectional stochastic lightning parameterization scheme within 2.dimensional domain. The simu-lated results show that the IC flashes have a bilevel channel structure and the altitudes of the hori-zontal channels are at the same heights of potential wells, which are supported by the previous VHF source observations and balloon soundings of electric field profile in the thundercloud. Further con-clusions are: (1. After an IC flash is initiated near the boundary between positve and nagetive charge zone, the negative (or positive) leader tends to propagate into the positive (or negative) charge zone. Both types of positive and negative IC flashes have been reproduced and their polarity depends on the up and down disposition of the positive and negative charge regions. (2. The extension range of leaders is correlative with the cloud charge distribution. The leader is possible to extend through the inverted charge region all over where it is extending, but keeps away from the isolated charge area of the same polarity. (3) The channel structures also depend on the electric potential distributions in the thundercloud. Before propagating into the central area of potential wells, the leader tends to extend along the direction with the maximum of potential gradient. Once extending away from the center of potential wells, the leader tends to extend along the direction with the slowest potential change. (4) The IC flash channels have the fractal feature with fractal dimension 1.45 before leaders pass through the central area of charge regions. The exponent decreases rapidly once leaders extend into the low-density charge regions. (5) The induced charges of opposite polarity are deposited in the leader channels within preexisting positive and negative charge regions during IC flash discharges. This causes a new and complicated charge distribution in the thundercloud, and the potential

关键词： IC, lightning parameterization, branched bilevel structure, fractal feature, propagation tendency.

Discovery of Permian island-arc basalts in the Cenxi area and the tectonic significance──A piece of evidence for the paleo-Tethyan tectonic belt in western Guangdong and eastern Guangxi

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Chinese science Bulletin 1998年第21期43卷 1838-1842页

作者： ZHANG Boyou 1. ZHAO Zhenhua 1. SHI Manquan 1. YANG Shufeng 2.and CHEN Hanlin 2.1. Guangzhou Institute of Geochemistry, Chinese Academy of sciences, Guangzhou 51.640, china 2. Department of Earth sciences, Zhejiang University, hangzhou 31.02., china Guangzhou Institute of Geochemistry Chinese Academy of Sciences Guangzhou China Department of Earth sciences Zhejiang University Hangzhou China

Cenxi Permian basalts are the late Palaeozoic island-arc type basalts first found in South china. REE and trace element characteristics and distribution patterns show that this volcanic formation, which has been isotopically dated at {1.1.MaB.P. by the 39Ar/ 40Ar method, is of an active continental marginal island arc type, and that the tectonic environment at that time was an island-arc marginal sea or minor ocean basin related with the paleo-Tethyan tectonic belt in western Guangdong-eastern Guangxi.

关键词： spilite-keratophyre pillow lava Permian continental margin paleo-Tethyan evolution.

Characteristics of fMRI BOLD signal and its neurophysiological mechanism

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Progress in Natural science:Materials International 2007年第6期17卷 630-638页

作者： Zhao Xiaohu1.2. Wu Yigen3 and Guo Shengli3(1. College of Life {1.s, Zhejiang University, hangzhou 31.058, {2. 2. Imaging Department of Tongji Hospital of Tongji University, Shanghai 2.0065, {2. 3. College of Mathematics and Physics, Nanjing University of Information {1. and Technology, Nanjing 2.0044, {2.) College of Life sciences Zhejiang University Hangzhou 310058 China Imaging Department Tongji Hospital Tongji University Shanghai 200065 China College of Mathematics and Physics Nanjing University of Information Science and Technology Nanjing 210044 China

The functional magnetic resonance imaging (fMRI) based on blood oxygen level dependent (BOLD) contrast has emerged as one of the most potent noninvasive tools for mapping brain function and has been widely used to explore physiological, pathological changes and mental activity in the brain. Exploring the nature and property of BOLD signal has recently attracted more attentions. Despite that great progress has been made in investigation of the characteristics and neurophysiological basis, the exact nature of BOLD signal remains unclear. In this paper we discuss the characteristics of BOLD signals, the nonlinear BOLD response to external stimuli and the relation between BOLD signals and neural electrophysiological recordings. Furthermore, we develop our new opinions regarding nonlinear BOLD response and make some perspectives on future study.

关键词： functional magnetic resonance imaging blood oxygen level dependent nonlinear response neural electrophysiological activity.

Optimization and design of a novel prescaler and its application to GPS receivers

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science {1.(Information sciences) 2011年第9期54卷 1938-1944页

作者： YU YunFeng 1.YE TianChun 1.& MA ChengYan 1.2.1.Institute of Microelectronics,Chinese Academy of {1.s,Beijing 1.002.,china 2.{2. Zhongke Microelectronics Ltd.,{2. 31.053,china 1. Institute of Microelectronics Chinese Academy of Sciences Beijing 100029 China2. Hangzhou Zhongke Microelectronics Ltd. Hangzhou 310053 China

In this work,a novel prescaler based upon new current mode logic (CML) flip-flop architecture applied to global positioning system (GPS) receivers is *** to traditional static current mode logic (CML) flip-flop,it introduces a clock-controlling transistor to reduce the time constant at sensing *** a result,the speed has been maximized and the working range has been *** phase noise of local oscillator (LO) signals coming from the prescaler can be lowered by 6 dB,and the interference of voltage controlled oscillator (VCO) to radio-frequency (RF) front-end apartments (low noise amplifier,mixer,etc.) will be diminished so that the sensitivity of GPS receivers is *** prescaler's maximum input frequency rises up to 6.9 GHz,30% higher than that of traditional architecture,and its power is only 2.1. mW when the supply voltage is 1.8 *** prescaler was manufactured in 0.1.-μm CMOS process,and it has been successfully applied to GPS receivers.

关键词： current mode logic (CML) prescaler quadrature local oscillator global positioning system radio-frequency front-end

Weight hierarchies of linear codes satisfying the Near-Chain condition

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Progress in Natural science:Materials International 2005年第9期15卷 784-792页

作者： LIU Zihui1.* and CHEN Wende2.1. {1. of Mathematical sciences, Peking University, Beijing 1.0871. {2. 2. Laboratory of Systems and Control and Key State Laboratory of Information Security, Institute of Systems science, Academy of Mathematics and Systems science, Chinese Academy of sciences, Beijing 1.0080, {2.) school of Mathematical {1.s Peking University Beijing 100871 China. Laboratory of Systems and Control and Key State Laboratory of Information Security Institute of Systems Science Academy of Mathematics and Systems Science Chinese Academy of Sciences Beijing 100080 China

The weight hierarchies of a linear [n,k;q] code C satisfying the Near-Chain condition are studied, almost all the weight hierarchies of such code are determined.

关键词： weight hierarchy Near-Chain condition difference sequence linear code.

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CO加富与不同光强对高羊茅幼苗生长的影响

草业科学 2024年

作者：朱智远贾辰雁丁孝伟沈娇张萌张浩男韩烈保 1.北京林业大学草坪研究所 2.内蒙古蒙草生态环境(集团)股份有限公司北京林业大学草坪研究所内蒙古蒙草生态环境(集团)股份有限公司

为探究CO2.度与光照强度对高羊茅（Festuca arundinacea）幼苗生长发育造成的影响，本研究用“交战2.”作为试验对象，以植物工厂中常见光气配比(CO2.度400 μmol·mol-1.光强300 μmol·m-2.s-1.为对照，设置不同CO2.度(大气浓度... 详细信息

为探究CO2.度与光照强度对高羊茅（Festuca arundinacea）幼苗生长发育造成的影响，本研究用“交战2.”作为试验对象，以植物工厂中常见光气配比(CO2.度400 μmol·mol-1.光强300 μmol·m-2.s-1.为对照，设置不同CO2.度(大气浓度400 μmol·mol-1.加富浓度1.00 μmol·mol-1.及不同光照强度(低光强1.0 μmol·m-2.s-1.中光强300 μmol·m-2.s-1.高光强450 μmol·m-2.s-1.，研究了CO2.富与光照强度互作对高羊茅幼苗的生长、生理特性与草坪外观质量的影响。试验表明，CO2.富会降低高羊茅的NDVI和色泽，导致草坪外观质量降低，但CO2.富与中等光照强度处理显著提升了高羊茅的生长速率与部分抗氧化酶活性（P2.s-1.CO2.度1.00 μmol·mol-1.较佳的光气配比，可以为植物工厂培育高羊茅提供理论参数。

关键词： CO 光照强度草坪外观质量理化性状根系性状

Two-dimensional thermoelasticity solution for functionally graded thick beams

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science {1.(Physics,Mechanics & Astronomy) 2006年第4期49卷 451-460页

作者： Lü Chaofeng1. CHEN Weiqiu1.& ZHONG Zheng2.1. Department of Civil Engineering, Zhejiang University, {1. 31.02., china 2. Key Laboratory of Solid Mechanics of Ministry of Education, {2. of Aerospace Engineering and Ap- plied Mechanics, Tongji University, Shanghai 2.0092. china Department of Civil Engineering Zhejiang University Hangzhou 310027 China Key Laboratory of Solid Mechanics of Ministry of Education School of Aerospace Engineering Applied Mechanics Tongji University Shanghai 200092 China

Two-dimensional thermoelasticity analysis of functionally graded thick beams is presented using the state space method coupled with the technique of differential quadrature. Material properties vary continuously and smoothly through the beam thickness, leading to variable coefficients in the state equation derived from the elasticity equations. Approximate laminate model is employed to translate the state equation into the one with constant coefficients in each layer. To avoid numerical instability, joint coupling matrices are introduced according to the continuity conditions at interfaces in the approximate model. The differential quadrature procedure is applied to discretizing the beam in the axial direction to make easy the treatment of arbitrary end conditions. A simply-supported beam with exponentially varying material properties is considered to validate the present method. Numerical examples are performed to investigate the influences of relative parameters.

关键词： state equation differential quadrature approximate laminate model joint coupling matrices thermal stresses.

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基于群体共识的动态大群体应急决策方法

系统科学与数学 2024年

作者：梁霞郭洁刘培德刘政敏 1.山东财经大学管理科学与工程学院 2.南京航空航天大学经济与管理学院南京航空航天大学经济与管理学院山东财经大学管理科学与工程学院

为提高应急决策的及时性,决策结果的可靠性和客观性,本文提出一种基于群体共识的动态大群体应急决策方法.首先,利用专家间的意见相似网络构建了考虑子群体内部凝聚力的聚类模型,并进一步探讨了考虑专家评价信息犹豫度的专家权重确定方法... 详细信息

为提高应急决策的及时性,决策结果的可靠性和客观性,本文提出一种基于群体共识的动态大群体应急决策方法.首先,利用专家间的意见相似网络构建了考虑子群体内部凝聚力的聚类模型,并进一步探讨了考虑专家评价信息犹豫度的专家权重确定方法.其次,利用专家间意见相似度和犹豫度建立了个性反馈调整机制用于指导未达成共识的专家调整评价.在上述工作的基础上,构建了考虑专家犹豫行为的动态大群体应急决策方法.最后,通过Z市特大暴雨案例分析验证了本文所提方法的可行性.同时,通过对比分析和仿真分析验证了本文所提方法可以有效的提高决策效率,降低决策的时间成本.

关键词：应急决策大群体群体共识聚类