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International Journal of Minerals,Metallurgy and Materials 2024年第2期31卷 301-314页

作者： Zhanghao wan Shiliang yang Desong Kong Dongbo Li Jianhang Hu Hua wang State Key Laboratory of Complex Nonferrous Metal Resources Clean Utilization Kunming University of Science and TechnologyKunming 650093China Southwest Copper Branch Yunnan Copper Co.Ltd.Kunming 650102China

The variation characteristics of bubble morphology and the thermal-physical properties of bubble boundary in the top-blown smelting furnace were explored by means of the computational fluid dynamics *** essential aspects of the fluid phase(e.g.,splashing volume,dead zone of copper slag,and gas penetration depth)were explored together with the effect of sinusoidal pulsating gas intake on the momentum-transfer performance between *** results illustrated that two relatively larger vortices and two smaller vortices appear in the bubble waist and below the lance,*** expansion of larger ones as well as the shrinking of smaller ones combine to cause the contraction of the bubble *** to the results of the case with a fixed gas injection velocity(V_(g)=58 m/s),the splashing volume and dead zone volume of the slag under the V_(g)=58+10sin(2πt)condition are reduced by 24.9%and 23.5%,respectively,where t represents the instant *** penetration depth and slag motion velocity of the latter are 1.03 and 1.31 times high-er than those of the former,respectively.

关键词： top-blown smelting furnace pulsed flow volume of fluid penetration depth splashing volume

Dynamics of Land Use/Land Cover Considering Ecosystem Services for a Dense-Population Watershed Based on a Hybrid Dual-Subject Agent and Cellular Automaton Modeling Approach

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Engineering 2024年第6期37卷 182-195页

作者： Yutong Li Yanpeng Cai Qiang Fu Xiaodong Zhang Hang wan Zhifeng yang Guangdong Provincial Key Laboratory of Water Quality Improvement and Ecological Restoration for Watersheds Institute of Environmental and Ecological EngineeringGuangdong University of TechnologyGuangzhou 510006China School of Water Conservancy and Civil Engineering Northeast Agricultural UniversityHarbin 150030China School of Environmental Science and Engineering Shandong UniversityQingdao 266000China

Land use/land cover represents the interactive and comprehensive influences between human activities and natural conditions,leading to potential conflicts among natural and human-related issues as well as among *** study introduced economic standards for farmers.A hybrid approach(CA-ABM)of cellular automaton(CA)and an agent-based model(ABM)was developed to effectively deal with social and land-use synergic issues to examine human–environment interactions and projections of land-use conversions for a humid basin in south *** attributes and socioeconomic data were used to analyze land use/land cover and its drivers of *** major modules of the CA-ABM are initialization,migration,assets,land suitability,and land-use change *** estimates of the factors influencing the urban land-use conversion probability were captured using parameters based on a spatial logistic regression(SLR)***,multicriteria evaluation(MCE)and Markov models were introduced to obtain empirical estimates of the factors affecting the probability of ecological land *** agent-based CA-SLR-MCE-Markov(ABCSMM)land-use conversion model was proposed to explore the impacts of policies on land-use *** model can reproduce observed land-use patterns and provide links for forest transition and urban expansion to land-use decisions and ecosystem *** results demonstrated land-use simulations under multi-policy scenarios,revealing the usefulness of the model for normative research on land-use management.

关键词： Land use/land cover Human-environment interactions Agent-based model Cellular automaton

Metal–ligand interfaces for well-defined gold nanoclusters

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Science China Chemistry 2024年第3期67卷 806-823页

作者： Dan yang Yating Wu Zhaotong Yuan Chunmei Zhou Yihu Dai Xiaoyue wan Yan Zhu Yanhui yang Institute of Advanced Synthesis School of Chemistry and Molecular EngineeringNanjing Tech UniversityNanjing 211816China School of Chemistry and Chemical Engineering Nanjing UniversityNanjing 210093China College of Material and Chemical Engineering Minjiang UniversityFuzhou 350108China

Ligand engineering for well-defined gold nanoclusters(Au NCs) is getting more extensive attention. Organizing the Au-ligand interfaces on gold NCs can achieve the structural and functional control. This review focuses on the Au-ligand interfaces including gold-phosphorus(Au-P), gold-sulfur(Au-S), gold-selenium(Au-Se), gold-carbon(Au-C), and gold-nitrogen(Au-N), derived from the bonding between Au atoms and the different ligands(e.g., organic phosphine, thiolate, selenolate, alkynyl,n-heterocyclic carbene and nitrogenous ligands). The formation mechanism of Au-ligand interfaces is well discussed. In addition, the effects of Au-ligand interfaces on the stability, optical property, and catalysis are also presented. We hope the advances in this research area can boost the development of Au NC sciences.

关键词： Au nanoclusters well-defined structures metal–ligand interfaces formation mechanism structure–property correlation

珠江河网密刺苦草种群衰退的表观性状特征指示

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水生态学杂志 2024年第4期45卷 155-164页

作者：李毅杨婉玲王超赖子尼李海燕刘乾甫高原麦永湛曾艳艺中国水产科学研究院珠江水产研究所广东广州510380 农业农村部珠江流域渔业生态环境监测中心广东广州510380 广东省水产动物免疫技术重点实验室广东广州510380 农业农村部外来入侵水生生物防控重点实验室广东广州510380 天津农学院水产学院天津300392

探讨珠江河网密刺苦草现存种群衰退特征及其主要影响因素,可为珠江河网水草床种群复建,珠江河网水生态功能和渔业资源持续利用和发展提供基础依据。于2017-2019年对珠江河网水草床及其中外海(S3)、小塘(S5)和榄核(S8)的密刺苦草开展调查... 详细信息

探讨珠江河网密刺苦草现存种群衰退特征及其主要影响因素,可为珠江河网水草床种群复建,珠江河网水生态功能和渔业资源持续利用和发展提供基础依据。于2017-2019年对珠江河网水草床及其中外海(S3)、小塘(S5)和榄核(S8)的密刺苦草开展调查,利用冗余分析(RDA)和主成分分析(PCA)等。多元统计方法分析密刺苦草的株高、株重、叶片指标等参数与环境因子关系,并结合2019年该区域密刺苦草种群急剧衰退情况探讨其衰退前的表观性状特征指示意义。结果显示,珠江河网密刺苦草衰退前一年度种群表观性状时空分布特征差异明显,S3和S8站位密刺苦草株高、株重等在2月、8月至12月期间呈现先增加后下降的趋势,而S5站位密刺苦草上述指标持续增加;12月,不同站位密刺苦草种群出现生长特征分化,S5站位密刺苦草进入花果期,而S3和S8站位密刺苦草则开始衰退。RDA结果显示,密刺苦草株高主要受水深、沉积物中粒径组分及沉积物总磷含量等影响,株重主要受沉积物总磷含量影响,不同站位群丛受到不同环境因子的影响制约。PCA结果显示,密刺苦草的9种表观性状可表征其克隆生长力、有性繁殖力和多年生长力,并决定其种群维持策略:一种以S5站位为代表,种群越冬期保持持续生长力,并进行有性繁殖资源分配,能适应环境变化,种群在次年得以维持和延续;另一种以S3和S8为代表,种群在越冬期生长力减弱,无有性繁殖资源分配,未能有效应对不利环境条件,最终导致两站位种群在次年急剧退化甚至消失。

关键词：密刺苦草表观性状有性繁殖种群恢复珠江河网

维普期刊数据库博看期刊

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杭州国家版本馆恒温恒湿空调系统调适

浙江建筑 2024年第2期41卷 55-59页

作者：金涛李志刚万阳张浩余红英浙江省建筑设计研究院有限公司浙江杭州310006 浙江省建工集团有限责任公司浙江杭州310013

恒温恒湿空调作为一种工艺性专用空调系统,对受控的室内环境温度和湿度有严格要求,而且维护系统运行需要相当高的能耗。在此以杭州国家版本馆项目为例,介绍了恒温恒湿空调系统的调适过程,分析水系统静态水力平衡、水系统最不利压差调整... 详细信息

恒温恒湿空调作为一种工艺性专用空调系统,对受控的室内环境温度和湿度有严格要求,而且维护系统运行需要相当高的能耗。在此以杭州国家版本馆项目为例,介绍了恒温恒湿空调系统的调适过程,分析水系统静态水力平衡、水系统最不利压差调整、风系统合理组织气流、水泵和风机变频调节、系统异常情况处理、气温反常变化应对等技术,并给出了有效的解决方案,为系统稳定节能运行提供良好保证。

关键词：恒温恒湿调适变频节能

Identification and Molecular Characterization of the Alkaloid Biosynthesis Gene Family in Dendrobium catenatum

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Phyton-International Journal of Experimental Botany 2024年第1期93卷 81-96页

作者： Liping yang Xin wan Runyang Zhou Yingdan Yuan College of Horticulture and Landscape Architecture Yangzhou UniversityYangzhouChina Jiangsu Academy of Forestry NanjingChina Jiangsu yangzhou Urban Forest Ecosystem National Observation and Research Station YangzhouChina

As one of the main active components of Dendrobium catenatum, alkaloids have high medicinal value. The physicochemicalproperties, conserved domains and motifs, phylogenetic analysis, and cis-acting elements of the genefamily members in the alkaloid biosynthesis pathway of D. catenatum were analyzed by bioinformatics, and theexpression of the genes in different years and tissues was analyzed by qRT-PCR. There are 16 gene families,including 25 genes, in the D. catenatum alkaloid biosynthesis pathway. The analysis of conserved domains andmotifs showed that the types, quantities, and orders of domains and motifs were similar among members ofthe same family, but there were significant differences among families. Phylogenetic analysis indicated that thegene family members showed some evolutionary conservation. Cis-acting element analysis revealed that therewere a large number of light-responsive elements and MYB (v-myb avian myeloblastosis viral oncogene homolog)-related elements in these genes. qRT-PCR showed that expressions of gene family members involved in alkaloidsynthesis were different in different years and tissues of D. catenatum. This study provides a theoretical basisfor further exploration of the regulatory mechanisms of these genes in the alkaloid biosynthesis of D. catenatum.

关键词： Dendrobium catenatum gene family alkaloid biosynthesis

HCSP-Net:A Novel Model of Age-Related Macular Degeneration Classification Based on Color Fundus Photography

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Computers, Materials & Continua 2024年第4期79卷 391-407页

作者： Cheng wan Jiani Zhao Xiangqian Hong Weihua yang Shaochong Zhang College of Electronic and Information Engineering/College of Integrated Circuits Nanjing University of Aeronautics and AstronauticsNanjing211106China Shenzhen Eye Institute Shenzhen Eye HospitalJinan UniversityShenzhen518040China

Age-related macular degeneration(AMD)ranks third among the most common causes of *** the most conventional and direct method for identifying AMD,color fundus photography has become prominent owing to its consistency,ease of use,and good quality in extensive clinical *** this study,a convolutional neural network(CSPDarknet53)was combined with a transformer to construct a new hybrid model,*** hybrid model was employed to tri-classify color fundus photography into the normal macula(NM),dry macular degeneration(DMD),and wet macular degeneration(WMD)based on clinical classification manifestations,thus identifying and resolving AMD as early as possible with color fundus *** further enhance the performance of this model,grouped convolution was introduced in this study without significantly increasing the number of ***-Net was validated using an independent test *** average precision of HCSPNet in the diagnosis of AMD was 99.2%,the recall rate was 98.2%,the F1-Score was 98.7%,the PPV(positive predictive value)was 99.2%,and the NPV(negative predictive value)was 99.6%.Moreover,a knowledge distillation approach was also adopted to develop a lightweight student network(SCSP-Net).The experimental results revealed a noteworthy enhancement in the accuracy of SCSP-Net,rising from 94%to 97%,while remarkably reducing the parameter count to a quarter of *** attribute positions SCSP-Net as a highly suitable candidate for the deployment of resource-constrained devices,which may provide ophthalmologists with an efficient tool for diagnosing AMD.

关键词： Computer-aided diagnosis deep learning age-related macular degeneration transformer

Scale Consistency Quantification for Subjective Evaluation of Vehicle Dynamics

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Automotive Innovation 2019年第2期2卷 121-126页

作者： wan’an yang Pan Asia Automotive Technical Center Co.Ltd. No.2199 Jufeng RoadPudongShanghaiChina

The subjective evaluation of vehicle dynamics performance is widely applied in different stages of vehicle ***,the rating result has frequently been challenged because it is easily affected by various subjective and objective ***,there is no suitable index for determining evaluator’s consistency when performing a subjective evalua-tion of vehicle *** evaluation is quite unique,with limited samples,multiple indices,and poor repeatability,in addition to being stratified and two *** cross-grouped factor analysis(CFA)method is proposed to identify the scale for a subjective evaluation and to quantify its *** application case study revealed that the proposed method is effective.

关键词： Subjective evaluation Consistency Quantification Cross-grouped factor analysis

Numerical investigation of the coupled aero-hydrodynamic performances of a semi-submersible floating offshore wind turbine with inclined columns

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Journal of Hydrodynamics 2024年第2期36卷 316-330页

作者： Ying-jie Xue Xiao-long yang Wei-wen Zhao De-cheng wan Computational Marine Hydrodynamics Lab(CMHL) School of Naval ArchitectureOcean and Civil EngineeringShanghai Jiao Tong UniversityShanghai200240China Offshore Oil Engineering Co.Ltd. Tianjin300461China

Numerical investigations of floating platforms with different outer column inclined angles under two operating conditions of regular wave and irregular wave are presented in this paper.A coupled aero-hydrodynamic computational fluid dynamics in-house solver FOWT-UALM-SJTU is applied for the ***,the validation for wave and wind generation are conducted to determine mesh distribution *** on these,the hydrodynamic motion response,aerodynamic performance and wake flow are analyzed to explore the impact of inclined *** spectral analysis on the motion response under wave action,discuss the aerodynamic attack angle and inflow wind velocity along the blade spanwise direction in detail,reveal different trends in wake development and *** results show that for the regular wave condition with the increase of inclined angles,the equilibrium position of surge motion is constantly rising,while pitch is *** maximum root mean square(rms)value occurs at angle=30°,compared with the original OC4 FOWT,the rms in power and thrust increase 0.35%,0.71%.And there are two low regions of attack angle and high regions of axial inflow velocity,corresponding to aerodynamic *** spectral analysis indicates that the natural frequency of pitch motion will increase with inclined ***,from the middle to far region of wake flow,the velocity recovery of FOWT with inclined angle will become faster,which is beneficial for downstream turbines to enhance more wind energy.

关键词： Floating offshore wind turbine numerical simulation aero-hydrodynamic coupled analysis floating platform with inclinedcolumns wake flow recovery

Numerical Study on the Aerodynamic and Fluid−Structure Interaction of An NREL-5MW Wind Turbine

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China Ocean Engineering 2024年第3期38卷 363-378页

作者： ZHAO Mi YU wan-li wanG Pi-guang QU yang DU Xiu-li Key Laboratory of Urban Security and Disaster Engineering of Ministry of Education Beijing University of TechnologyBeijing 100124China State Key Laboratory of Bridge Engineering Safety and Resilience Beijing University of TechnologyBeijing 100124China

A 5-MW wind turbine has been modeled and analyzed for fluid-structure interaction and aerodynamic *** this study, a full-scale model of a 5-MW wind turbine is first developed based on a computational fluid dynamics(CFD) approach, in which the unsteady, noncompressible Reynolds Averaged Navier-Stokes(RANS) method is used. The main focus of the study is to analyze the tower shadow effect on the aerodynamic performance of the wind turbine under different inlet flow conditions. Subsequently, the finite element model is established by considering fluid/structure interactions to study the structural stress, displacement, strain distributions and flow field information of the structure under the uniform wind speed. Finally, the fluid-structure interaction model is established by considering turbulent wind and the tower shadow effect. The variation rules of the dynamic response of the one-way and two-way fluid-structure interaction(FSI) models under different wind speeds are analyzed, and the numerical calculation results are compared with those of the centralized mass model. The results show that the tower shadow effect and structural deformation are the main factors affecting the aerodynamic load fluctuation of the wind turbine, which in turn affects the aerodynamic performance and structural stability of the blades. The structural dynamic response of the coupled model shows significant similarity, while the structural displacement response of the former exhibits less fluctuation compared with the conventional centralized mass model. The one-way fluid-structure interaction(FSI)model shows a higher frequency of stress-strain and displacement oscillations on the blade compared with the two-way FSI model.

关键词： computational fluid dynamics methods(CFD) tower shadow effect aerodynamic performance fluidstructure interaction space flow field