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Coupled effects of pH and kaolinite colloids on antibiotic transport in porous media

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Pedosphere 2023年第5期33卷 788-799页

作者： Shuhua JI Xiaowen LIU Xiu MENG shaohui XU Qing LIN Department of Environmental Science and Engineering Qingdao UniversityQingdao 266071China

Antibiotics can interact with natural colloids and the surrounding media upon entry into soil and groundwater systems,which significantly alters their dynamic behavior and complicates our understanding of antibiotic fate and transport in porous *** this study,co-transport of antibiotics and kaolinite colloids was systematically investigated using combined column experiments and numerical simulation under different pH ***(SDZ)transport was enhanced by kaolinite colloids under neutral and alkaline conditions,which was attributed to the higher mobility of colloids as SDZ carriers,as well as competitive ***,most injected SDZ was transported in a dissolved form owing to the low sorption capacity of SDZ to kaolinite colloids and quartz *** colloid-facilitated transport model provided a good description of total SDZ transport,but underestimated colloidal SDZ transport using parameters from kinetic sorption *** colloids significantly promoted ciprofloxacin(CIP)transport at pH 4.0,but inhibited it at pH 7.0 ***,enhanced CIP transport was due to the decreased number of effective sorption sites on quartz sand and the increased desorption of CIP from kaolinite *** neutral and alkaline conditions,deposited colloids provided additional sorption sites for CIP,which contributed to CIP ***,CIP significantly inhibited the transport of kaolinite colloids owing to the increases in colloidal aggregate size and zeta ***,our results highlighted the different effects of mobile and immobile colloids on antibiotic transport,in addition to the implications of antibiotic speciation and clay colloids when predicting the transport behavior of these compounds.

关键词： aadvection-dispersion equation ciprofloxacin colloid-facilitated transport model numerical simulation sulfadiazine two-site model

Carbon budgets of three temperate forest ecosystems in Dongling Mt.,Beijing,China

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Science China Earth Sciences 2007年第1期50卷 92-101页

作者： FANG JingYun LIU GuoHua ZHU Biao WANG XiaoKe LIU shaohui Department of Ecology College of Environmental Sciences and Key Laboratoryfor Earth Surface Processes of the Ministry of Education Peking University Beijing 100871 China

There is a general agreement that forest ecosystems in the NorthernHemisphere function as significant sinks for atmospheric CO_2; however, their magnitude anddistribution remain large uncertainties. In this paper, we report the carbon (C) stock and itschange of vegetation, forest floor detritus, and mineral soil, annual net biomass increment andlitterfall production, and respiration of vegetation and soils between 1992 to 1994, for threetemperate forest ecosystems, birch (Betula platyphylla) forest, oak (Ouercus liaotungensis) forestand pine (Pinus tabulaeformis) plantation in Mt. Dongling, Beijing, China. We then evaluate the Cbudgets of these forest ecosystems. Our results indicated that total C density (organic C perhectare) of these forests ranged from 250 to 300 t C ha^(-1), of which 35—54 t C ha^(-1) fromvegetation biomass C and 209-244 t C ha^(-1) from soil organic C (1 m depth, including forest floordetritus). Biomass C of all three forests showed a net increase, with 1.33—3.55 t C ha^(-1) a^(-1)during the study period. Litterfall production, vegetation autotrophic respiration, and soilheterotrophic respiration were estimated at 1.63—2.34,2.19—6.93, and 1.81 —3.49 t C ha^(-1)a^(-1), respectively. Ecosystem gross primary production fluctuated between 5.39 and 12.82 t Cha^(-1) a^(-1), about half of which (46%-59%, 3.20-5.89 t C ha^(-1) a^(-1)) was converted to netprimary production. Our results suggested that pine forest fixed C of 4.08 t ha^(-1) a^(-1), whereassecondary forests (birch and oak forest) were nearly in balance in CO_2 exchange between theatmosphere and ecosystems.

关键词： carbon budget carbon density carbon flux mountainous area temperate forest.

Multidisciplinary Modeling and Optimization Method of Remote Sensing Satellite Parameters Based on SysML-CEA

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Computer Modeling in Engineering & Sciences 2023年第5期135卷 1413-1434页

作者： Changyong Chu Chengfang Yin Shuo Shi shaohui Su Chang Chen School of Mechanical Engineering Hangzhou Dianzi UniversityHangzhou310018China State Key Laboratory of Digital Manufacturing Equipment and Technology Huazhong University of Science and TechnologyWuhan430074China

To enhance the efficiency of system modeling and optimization in the conceptual design stage of satellite parameters,a system modeling and optimization method based on System Modeling Language and Co-evolutionary Algorithm is *** first,the objectives of satellite mission and optimization problems are clarified,and a design matrix of discipline structure is constructed to process the coupling relationship of design variables and constraints of the orbit,payload,power and quality *** order to solve the problem of increasing nonlinearity and coupling between these disciplines while using a standard collaborative optimization algorithm,an improved genetic algorithm is proposed and applied to system-level and discipline-level ***,the CO model of satellite parameters is solved through the collaborative simulation of Cameo Systems Modeler(CSM)and *** result obtained shows that the method proposed in this paper for the conceptual design phase of satellite parameters is efficient and *** can shorten the project cycle effectively and additionally provide a reference for the optimal design of other complex projects.

关键词： SysML remote sensing satellite multidisciplinary design optimization collaborative optimization

Two-Dimensional Metallophthalocyanine Nanomaterials for Electrocatalytic Energy Conversion

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Energy & Environmental Materials 2024年第4期7卷 364-385页

作者： Xinqi Wang shaohui Sun Jiahao Yao Hao Wan Renzhi Ma Wei Ma School of Chemical Engineering and Zhongyuan Critical Metals Laboratory Zhengzhou UniversityZhengzhou 450001China Research Center for Materials Nanoarchitectonics(MANA) National Institute for Materials Science(NIMS)Namiki 1-1TsukubaIbaraki 305-0044Japan

Growing energy demand drives the rapid development of clean and reliable energy *** the past years,the exploration of novel materials with considerable efficiency and durability has drawn attention in the area of electrochemical energy *** metal macrocyclic metallophthalocyanines(MPcs)-based catalysts with a peculiar 2D constitution have emerged with a promising future account of their highly structural tailorability and molecular functionality which greatly extend their functionalities as electrocatalytic materials for energy *** review summarizes the systematic engineering of synthesis of MPcs and their analogs in detail,and mostly pays attention to the frontier research of MPc-based high-performance catalysts toward different electrocatalytic processes concerning hydrogen,oxygen,water,carbon dioxide,and nitrogen,with a particular focus on discussing the interrelationship between the electrocatalytic activity and component/structure,as well as functional applications of ***,we give the gaps that need to be addressed after much thought.

关键词： conjugated nanostructure electrocatalysis 2D metallophthalocyanines

Distribution of Na+and Mechanical Properties of Hardened Body of Alkali-activated Cementitious Materials

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Journal of Wuhan University of Technology(Materials Science) 2023年第4期38卷 849-856页

作者：卞立波 TAO Zhi 王秀芳 WANG shaohui YE Kangjun HU Xingbo School of Civil and Traffic Engineering Beijing University of Civil Engineering and ArchitectureBeijing102616China Beijing Key Laboratory of Functional Materials for Building Structure and Environment Remediation School of ScienceBeijing University of Civil Engineering and ArchitectureBeijing102616China Beijing Shoufa Tianren Ecological Landscape Co. LtdBeijing102699China

To explore the distribution of and the mechanical properties(compressive strength)of the hardened body of alkali slag-fly ash cementitious materials,this study was conducted by using the XRD,FTIR,SEM/EDS,and other test methods in three conditions:airtight drying(AD),airtight immersion(AI),and airtight soaking(AS).The 1D distribution law of free of hardened body under standard curing conditions was *** experimental results show that under standard curing conditions,the 1D distribution of within 0d-3 d shows a∨-shaped distribution,within 3-7 d show a∧-shaped distribution,and within 7-28 d tends to be *** test results of leaching rate show that the free was the most stable under AD conditions and the hardened body bound the most by XRD,FTIR and SEM/*** the compressive strength of the hardened body was the *** compressive strength of 28th reached 95.9 *** definite distribution of provides an important reference for the strength development and durability evaluation of the hardened body of alkaliexcited cementitious materials.

关键词： alkali-activated cementitious materials ion migration leaching rate curing condition compressive strength

Analysis of Non-Orthogonal Multiple Access for 5G

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China Communications 2016年第S2期13卷 52-66页

作者： Yingmin Wang Bin Ren shaohui Sun Shaoli Kang Xinwei Yue School of Information and Communication Engineering Beijing University of Posts & Telecommunications State Key Laboratory of Wireless Mobile Communications China Academy of Telecommunication Technology National Engineering Laboratory of New Generation Mobile Communication Network and Chip Technology China Academy of Telecommunication Technology School of Electronic and Information Engineering Beihang University

The major challenge faced by the fifth generation(5G) mobile network is higher spectral efficiency and massive connectivity,i.e.,the target spectrum efficiency is 3 times over 4G,and the target connection density is one million devices per square *** requirements are difficult to be satisfied with orthogonal multiple access(OMA) ***-orthogonal multiple access(NOMA) has thus been proposed as a promising candidate to address some of the challenges for *** this paper,a comprehensive survey of different candidate NOMA schemes for 5G is presented,where the usage scenarios of5 G and the application requirements for NOMA are firstly discussed.A general framework of NOMA scheme is established and the features of typical NOMA schemes are analyzed and *** focus on the recent progress and challenge of NOMA in standardization of international telecommunication union(ITU),and 3rd generation partnership project(3GPP).In addition,prototype development and future research directions are also provided respectively.

关键词： 5G non-orthogonal multiple access NOMA SCMA PDMA MUSA MPA SIC

Sparse Autoencoder-based Multi-head Deep Neural Networks for Machinery Fault Diagnostics with Detection of Novelties

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Chinese Journal of Mechanical Engineering 2021年第3期34卷 146-157页

作者： Zhe Yang Dejan Gjorgjevikj Jianyu Long Yanyang Zi shaohui Zhang Chuan Li School of Mechanical Engineering Dongguan University of TechnologyDongguan 523808China School of Mechanical Engineering Xi’an Jiaotong UniversityXi’an 710049China Faculty of Computer Science and Engineering Ss.Cyril and Methodius UniversitySkopjeMacedonia

Supervised fault diagnosis typically assumes that all the types of machinery failures are ***,in practice unknown types of defect,i.e.,novelties,may occur,whose detection is a challenging *** this paper,a novel fault diagnostic method is developed for both diagnostics and detection of *** this end,a sparse autoencoder-based multi-head Deep Neural Network(DNN)is presented to jointly learn a shared encoding representation for both unsupervised reconstruction and supervised classification of the monitoring *** detection of novelties is based on the reconstruction ***,the computational burden is reduced by directly training the multi-head DNN with rectified linear unit activation function,instead of performing the pre-training and fine-tuning phases required for classical *** addressed method is applied to a benchmark bearing case study and to experimental data acquired from a delta 3D *** results show that its performance is satisfactory both in detection of novelties and fault diagnosis,outperforming other state-of-the-art *** research proposes a novel fault diagnostics method which can not only diagnose the known type of defect,but also detect unknown types of defects.

关键词： Deep learning Fault diagnostics Novelty detection Multi-head deep neural network Sparse autoencoder

Implementation of Caterpillar Inspired Rolling Gait and Nonlinear Control Strategy in a Spherical Robot

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Journal of Bionic Engineering 2018年第2期15卷 313-328页

作者： Abhra Roy Chowdhury Gim Song Soh shaohui Foong Kristin L. Wood Temasek Laboratories Engineering Product Development Pillar Singapore University of Technology and Design Singapore 487372 SUTD-MIT International Design Centre Singapore University of Technology and Design Singapore 487372

This paper presents a novel Central Pattern Generator （CPG） based rolling gait generation in a small-sized spherical robot and its nonlinear control mechanism. A rhythmic rolling pattern mimicking Pleurotya caterpillar is produced for the spherical robot locomotion. A synergetically combined feedforward-feedback control strategy is proposed. The feedforward component is generated from centrally connected network of CPGs in conjunction with nonlinear robot dynamics. Two nonlinear feedback control methods namely integral （first order） Sliding Mode Control （SMC） and High （or second） Order Sliding Mode Control （HOSMC） are proposed to regulate robot stability and gait robustness in the presence of matched parameter uncertainties and bounded external disturbances. Design, implementation and experimental evaluation of both roll gait control strategies for the spherical robot are done on smooth （indoor） and irregular （outdoor） ground surfaces, The performance of robot control is quantified by measuring the roll angle stability, phase plane convergence and wheel velocities. Experimental results show that proposed novel strategy is efficient in producing a stable rolling gait and robust control of a spherical robot on two different types of surfaces. It further shows that proposed high HOSMC strategy is more efficient in robust rolling gait control of a spherical robot compared to an integral first-order SMC on two different ground conditions.

关键词： bioinspired spherical robot rolling gait CPG rolling friction integral first-order SMC control HOSMC

Causes Leading to Formation of Shot Cokes and Measures for Its Prevention in Super Viscous Oil Delayed Coking Unit

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China Petroleum Processing & Petrochemical Technology 2007年第1期9卷 19-24页

作者： Chen Chunmao Zhang Feng Yan Guangxu Guo shaohui State Key Laboratory for Heavy Oil Processing China University of Petroleum Beijing 102249 Liaohe Petrochemical Corporation of PetroChina Panjin 124002

Shot cokes are frequently formed in the delayed coking unit treating the super viscous oil at PetroChina＇s Liaohe Petrochemical Company. Considerable work has been carded out to avoid the formation of shot cokes. The test results obtained have shown that the property of super viscous oil has played a key role in the formation of shot cokes. After adjusting and optimizing the process indices the operating regime of the delayed coking unit at a throughput of 118t/h of the super viscous oil is specified as follows： a reaction temperature of 498-502℃, a reaction pressure of 0.17-0.25 MPa, a recycle ratio of 0.5-0.6 and a fractionation tower bottom temperature of 355-365 ℃. In the meantime, the delayed coking process has adopted measures to enhance pre-fractionation of the feedstock to rationally remove light fractions and maintain a steady gas velocity in order to avoid the formation of shot cokes.

关键词： delayed coking unit super viscous oil shot cokes preventive methods