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Frontiers of Environmental Science & Engineering 2017年第2期11卷 165-174页

作者： Qingbin Guo sheng chang School of Engineering University of Guelph Guelph Ontario N 1G 2W1 Canada

Characterization of the molecular properties of soluble microbial products （SMP） is critical for understanding the membrane filtration and fouling mechanisms in anaerobic and aerobic membrane bioreactors （AnMBR ＆ MBR）. In this study, the distributions of the absolute molecular weight and intrinsic viscosity of SMP polysaccharides from an AnMBR were effectively determined by a high pertbrmance size exclusion chromatography （HPSEC） that was coupled with the refractive index （RI）,cliode array UV （DAUV）, right and low angle light scattering （LS）, and viscometer （Vis） detectors. Based on the tetra-detector HPSEC determined absolute molecular weights and intrinsic viscosity, a universal calibration relationship for the SMP polysaccharides was developed and the molecularconformations, average molecular weights~ and hydrodynamic sizes of the SMP polysaccharides were also explored. Two factors which can be derived from the tetra-detector HPSEC analysis were proposed for the characterization of the viscous and osmotic pressure properties of the SMP polysaccharides. In addition, it was also extrapolated how to analyze the resistance characteristics of the concentration polarization layers formed in membrane filtration based on the molecular properties determined by the tetra-detector HPSEC analysis.

关键词： Soluble microbial productExtracellular polymeric substanceMembrane bioreactorMembrane foulingMolecular weightIntrinsic viscosity

Effects of Doped Elements on Electrochemical Performance of Ni(OH)_2 Materials

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Chemical Research in Chinese Universities 2007年第4期23卷 452-455页

作者： LEE chang-sheng School of Chemical Engineering and Technology Tianjin University

High energy ball milling （HEBM） method was applied to synthesize Ni （OH）2 with different doped elements sub-stitution for Ni^2＋. The morphology, structure and electrochemical behavior of prepared powders were studied. The re-suits reveal that all the synthesized Ni（OH）2 particles were in sub-micron sizes and greatly agglomerated. Co-, Mg-,Fe- or Mn-doped Ni （OH） 2 was of β-phase with 0.400-0.500 nm crystal interlayer distance, while A1- and Zn-doped products displayed a-phase with larger crystal interlayer spaces. The electrochemical mechanisms of synthe-sized Ni（OH）2 electrodes were discussed by EIS spectra. The specific capacity of Co-doped Ni （OH）2 is 245 mA·h · g^-1, i. e. , 60 mA· h · g^-1 higher than that of Al-doped electrode, which has the highest discharging plat-form of a mid-voltage of 1.30 V.

关键词： Nickel hydroxide High energy ball milling method Metallic ion adulteration Electrochemical discharging capacity

Phase field simulation of single bubble behavior under an electric field

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Chinese Physics B 2018年第9期27卷 389-395页

作者： chang-sheng Zhu Dan Han sheng Xu School of Computer and Communication Lanzhou University of Technology State Key Laboratory of Gansu Advanced Processing and Recycling of Non-Ferrous Metal Lanzhou University of Technology

Based on the Cahn-Hilliard phase field model, a three-dimensional multiple-field coupling model for simulating the motion characteristics of a rising bubble in a liquid is established in a gas-liquid two-phase flow. The gas-liquid interface motion is simulated by using a phase-field method, and the effect of the electric field intensity on bubble dynamics is studied without electric field, or with vertical electric field or horizontal electric field. Through the coupling effect of electric field and flow field, the deformation of a single rising bubble and the formation of wake vortices under the action of gravity and electric field force are studied in detail. The correctness of the results is verified by mass conservation, and the influences of different electric field directions and different voltages on the movement of bubbles in liquid are considered. The results show that the ratio of the length to axis is proportional to the strength of the electric field when the air bubble is stretched into an ellipsoid along the electric field line under the action of electrostatic gravity and surface tension. In addition, the bubble rising speed is affected by the electric field, the vertical electric field accelerates the bubble rise, and the horizontal direction slows it down.

关键词： electro-hydro dynamics numerical simulation phase field method bubble

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医院后勤安全管理体系构建探析

中国医院 2025年第3期29卷 98-100页

作者：翁振锋昌盛徐杨刘玉燕深圳市第二人民医院广东省深圳市518035 中国医学科学院肿瘤医院深圳医院广东省深圳市518116

分析了医院后勤安全管理的特点,提出了构建医院后勤安全管理体系的框架,包括组织框架搭建、制度管理等方面,探讨了医院后勤安全管理体系的构建与实施,为提高医院后勤安全管理水平提供参考。未来,医院应继续深化后勤安全管理体系的构建探... 详细信息

分析了医院后勤安全管理的特点,提出了构建医院后勤安全管理体系的框架,包括组织框架搭建、制度管理等方面,探讨了医院后勤安全管理体系的构建与实施,为提高医院后勤安全管理水平提供参考。未来,医院应继续深化后勤安全管理体系的构建探索,不断完善和优化各项安全管理措施,为医疗服务的持续改进和患者安全提供有力支撑。

关键词：医院后勤安全管理医院管理管理体系

A learning framework based on weighted knowledge transfer for holiday load forecasting

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Journal of Modern Power Systems and Clean Energy 2019年第2期7卷 329-339页

作者： Pan ZENG chang sheng Min JIN College of Computer Science and Electronic Engineering Hunan University

Since the variation pattern of load during holidays is different than that of non-holidays, forecasting holiday load is a challenging task. With a focus on this problem, we propose a learning framework based on weighted knowledge transfer for daily peak load forecasting during ***,we select source cities which can provide extra hidden knowledge to improve the forecast accuracy of the load of the target city. Then, all the instances which are from source cities and the target city will be weighted and trained by the improved weighted transfer learning algorithm which is based on the TrAdaBoost algorithm and can decrease negative transfer. We evaluate our method with the classical support vector machine method and a method based on knowledge transfer on a real data set, which includes eleven cities in Guangdong province of China,to illustrate the performance of the method. To solve the problem of limited historical holiday load data, we transfer the data from nearby cities based on the fact that nearby cities in Guangdong province of China have a similar economic development level and similar load variation pattern. The results of comparative experiments show that the framework proposed by this paper outperforms these methods in terms of mean absolute percent error and mean absolute scaled error.

关键词： Load forecasting Holiday effect Sparse data Weighted knowledge transfer

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串联型惯容系统多自由度结构地震响应分析

计算力学学报 2025年第01期42卷 130-138页

作者：管涛王善库葛新广王昌盛信阳职业技术学院建筑工程学院柳州工学院土木建筑学院黄淮学院建筑工程学院

研究串联型惯容系统多自由度结构随机地震响应的简明封闭解，分析了惯容系统参数及设置位置对结构减震性能的影响。首先，根据串联型惯容系统力学构造图，建立多自由度结构-惯容系统耦合地震动方程。其次，运用二次式分解法推导出建筑... 详细信息

研究串联型惯容系统多自由度结构随机地震响应的简明封闭解，分析了惯容系统参数及设置位置对结构减震性能的影响。首先，根据串联型惯容系统力学构造图，建立多自由度结构-惯容系统耦合地震动方程。其次，运用二次式分解法推导出建筑结构节点相对于地面的绝对位移、层间节点位移及串联型惯容系统阻尼力等系列响应的0～2阶谱矩的简明封闭解。最后，通过算例，验证所提方法的正确性并研究了惯容系统参数及设置位置对结构减震性能的影响。研究表明，串联型惯容系统对结构层间位移和顶层绝对位移的减震性能具有非一致性特点；在层间位移较大的楼层设置惯容系统的布置策略是经济可行的。本文可为惯容系统实际工程应用提供参考。

关键词：串联惯容系统简明封闭解二次式分解法参数分析阻尼器布置策略

Hard magnetization direction and its relation with magnetic permeability of highly grain-oriented electrical steel

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International Journal of Minerals,Metallurgy and Materials 2014年第11期21卷 1077-1082页

作者： Hao Wang chang-sheng Li Tao Zhu State Key Laboratory of Rolling and Automation Northeastern University

The magnetic properties of highly grain-oriented electrical steel vary along different directions. In order to investigate these properties, standard Epstein samples were cut at different angles to the rolling direction. The hard magnetization direction was found at an angle of 60° to the rolling direction. To compare the measured and fitting curves, when the magnetic field intensity is higher than 7000 A/m, it is appropriate to simulate the relation of magnetic permeability and magnetization angle using the conventional elliptical model. When the magnetic field intensity is less than 3000 A/m, parabolic fitting models should be used; but when the magnetic field intensity is between 3000 and 7000 A/m, hybrid models with high accuracy, as proposed in this paper, should be applied. Piecewise relation models of magnetic permeability and magnetization angle are significant for improving the accuracy of electromagnetic engineering calculations of electrical steel, and these new models could be applied in further industrial applications.

关键词： electrical steel magnetization direction magnetic permeability mathematical models

Multi-bubble motion behavior of electric field based on phase field model

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Chinese Physics B 2019年第3期28卷 238-245页

作者： chang-sheng Zhu Dan Han Li Feng sheng Xu School of Computer and Communication Lanzhou University of TechnologyLanzhou 730050China State Key Laboratory of Gansu Advanced Processing and Recycling of Non-Ferrous Metal Lanzhou 730050China

By coupling the phase field model with the continuity equation of incompressible fluid, Navier–Stokes equation,electric field equation, and other governing equations, a multi-field coupling model for multi-bubble coalescence in a viscous fluids is established. The phase field method is used to capture the two-phase interface. The motion and coalescence of a pair of coaxial bubbles under an external uniform electric field and the effects of different electric field strengths on the interaction and coalescence of rising bubbles are studied. The results show that the uniform electric field accelerates the collision and coalescence process of double bubbles in the fluid, and increases the rising velocity of the coalesced *** electric field with an intensity of E = 2 kV/mm is reduced about 2 times compared with that without electric field in coalescence time. When the electric field strength is strong(E ≥ 1 kV/mm), the coalesced bubble will rupture before it rises to the top of the calculation area, and the time of the bubble rupturing also decreases with the increase of the electric field strength. The phase field method is compared with the simulation results of Lattice Boltzmann Method(LBM), and the shape of bubble obtained by the two methods is in good agreement, which verifies the correctness of the calculation model.

关键词： electro-hydro dynamics multi-bubble phase field

Geometric Origin of Staggered Fermion：Direct Product K—Cycle

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Communications in Theoretical Physics 2003年第5期39卷 519-520页

作者： DAIJian XIONGChuang-sheng SONGXing-chang InstituteofTheoreticalPhysics SchoolofPhysicsPekingUniversityBeijing100871China

Staggered formalism of lattice fermion can be cast into a form of direct product K-cycle in noncommutative geometry. We prove the correspondence between this staggered K-cycle and a canonically defined K-cycle for fin... 详细信息

关键词： staggered fermion K-cycle direct product finitely generated Abelian group

Continuous biohydrogen production from diluted molasses in an anaerobic contact reactor

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Frontiers of Environmental Science & Engineering 2011年第1期5卷 140-148页

作者： sheng chang Jianzheng LI Feng LIU State Key Laboratory of Urban Water Resource and Environment School of Municipal and Environmental EngineeringHarbin Institute of TechnologyHarbin 150090China

An anaerobic contact reactor (ACR) systemcomprising a continuous flow stirred tank reactor (CSTR)with settler to decouple the hydraulic retention time(HRT) from solids retention time (SRT) was developedfor fermentative hydrogen production from dilutedmolasses by mixed microbial cultures. The ACR wasoperated at various volumetric loading rates (VLRs) of20-44 kgCOD·m^(-3)·d^(-1) with constant HRT of 6 h undermesophilic conditions of 35°C. The SRTwas maintained atabout 46-50 h in the system. At the initial VLR of20 kgCOD·m^(-3)·d^(-1), the hydrogen production rate droppedfrom 22.6 to 1.58 L·d^(-1) as the hydrogen was consumed bythe hydrogentrophic methanogen. After increasing theVLR to 28 kgCOD·m^(-3)·d^(-1) and discharging the sludge for6 consecutive times, the hydrogentrophic methanogenswere eliminated, and the hydrogen content reached 36.4%.As the VLR was increased to 44 kgCOD·m^(-3)·d^(-1), thehydrogen production rate and hydrogen yield increased to42.1 L·d^(-1) and 1.40 mol H2·molglucose-consumed^(-1),respectively. The results showed that a stable ethanoltypefermentation that favored hydrogen production inthe reactor was thus established with the sludgeloading rate (SLR) of 2.0-2.5 kgCOD·kgMLVSS-1·d^(-1).It was found that the ethanol increased more than otherliquid fermentation products, and the ethanol/acetic acid(mol/mol) ratio increased from 1.27 to 2.45 when the VLRincreased from 28 to 44 kgCOD·m^(-3)·d^(-1), whereas thehydrogen composition decreased from 40.4% to 36.4%.The results suggested that the anaerobic contact reactorwas a promising bioprocess for fermentative hydrogenproduction.

关键词： fermentative hydrogen production anaerobic contact reactor(ACR) sludge loading rate(SLR) butyric acid-type fermentation ethanol-type fermentation