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Particuology 2024年第6期89卷 246-257页

作者： Yanghong Wang Ziqiang Meng Zipei Zhang Min xia Li xia Wei Li School of Optical and Electronic Information Huazhong University of Science and TechnologyWuhan 430074China

Dynamic light scattering(DLS)is a nondestructive,well-established technique for the size characterization of proteins,nanoparticles,polymers,and colloidal ***,current DLS techniques are only applied to particle groups of single composition due to the limitation of their inversion *** this study,we propose a particle size distribution inversion algorithm based on the Tikhnonov regularization method that can be applied to the dual-substance particle *** algorithm retrieves the particle size distributions of two substances,respectively,by taking advantage of their refractive index *** simulation results reveal that the algorithm has excellent accuracy and stability when the scattering angle is 30°.Instead of the original identity matrix,the first-order difference matrix and second-order difference matrix are used as the regular matrix when utilizing the Tikhnonov algorithm,which obviously improves the anti-interference,accuracy,and stability of the ***,the inversion of particle size distribution is carried out at a 0.01%–1%noise level,which shows that the algorithm has an available antinoise ***,experimental particle size measurements for a mixture of polystyrene beads and toner particles demonstrate that the proposed algorithm is superior to the traditional Tikhnonov algorithm in applicability and accuracy.

关键词： Dynamic light scattering Dual-substance mixture Particle sized istribution Tikhnonov regularization

Pretreating and normalizing metabolomics data for statistical analysis

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Genes & Diseases 2024年第3期11卷 188-205页

作者： Jun Sun Yinglin xia Division of Gastroenterology and Hepatology Department of MedicineDepartment of Microbiology/ImmunologyUIC Cancer CenterUniversity of Illinois ChicagoJesse Brown VA Medical Center Chicago(537)ChicagoIL 60612USA Division of Gastroenterology and Hepatology Department of MedicineUniversity of Illinois ChicagoChicagoIL 60612USA

Metabolomics as a research field and a set of techniques is to study the entire small molecules in biological *** is emerging as a powerful tool generally for pre-cision ***,integration of microbiome and metabolome has revealed the mechanism and functionality of microbiome in human health and ***,metabo-lomics data are very ***/pretreating and normalizing procedures on metabolomics data are usually required before statistical *** this review article,we comprehensively review various methods that are used to preprocess and pretreat metabolo-mics data,including MS-based data and NMR-based data preprocessing,dealing with zero and/or missing values and detecting outliers,data normalization,data centering and scaling,data *** discuss the advantages and limitations of each *** choice for a suitable preprocessing method is determined by the biological hypothesis,the characteristics of the data set,and the selected statistical data analysis *** then provide the perspective of their applications in the microbiome and metabolome research.

关键词： Data centering and scaling Data normalization Data transformation Missing values MS-Baseddata preprocessing NMRData preprocessing Outliers Preprocessing/pretreatment

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基于云控制的闭环OBE在线教学模式探索

实验室研究与探索 2021年第7期40卷 149-153页

作者：李怡然夏元清北京理工大学自动化学院北京100081

2020年初新冠疫情爆发,各地高校依托在线教育平台进行线上授课,力求达到与课堂授课实质等效的教学效果。线上授课过程中,教师无法解决学生的监管难、学习信息反馈慢、实践实验无法进行的教学困境。针对此问题,提出了基于云控制的闭环在... 详细信息

2020年初新冠疫情爆发,各地高校依托在线教育平台进行线上授课,力求达到与课堂授课实质等效的教学效果。线上授课过程中,教师无法解决学生的监管难、学习信息反馈慢、实践实验无法进行的教学困境。针对此问题,提出了基于云控制的闭环在线教育模式,根据OBE教学理念,在已有的作业、测验等知识理解反馈环节基础上,增加学生端状态监控和评估系统,评估学生学习状态并动态调整教学节奏,建立学生状态实时反馈;增加基于云控制的实验室设备网络系统、监控系统、云端设备管理系统和学生接入管理系统,学生通过云控制系统完成实验,建立学生综合能力反馈。最终达到"学生-教师-实验室"三位一体的云-网-边-端在线教学平台,达成基于OBE理念的闭环在线教学新模式,实现与课堂教学的实质等效。

关键词：闭环在线教学云控制 OBE理念教学模式

Deciphering the linear relationship in the activity of the oxygen reduction reaction on Pt electrodes:A decisive role of adsorbates

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Journal of Energy Chemistry 2024年第7期94卷 70-77页

作者： Haowen Cui Yan-xia Chen Hefei National Research Center for Physical Sciences at Microscale and Department of Chemical Physics University of Science and Technology of ChinaHefei 230026AnhuiChina

Despite substantial efforts in developing high-performance catalysts for the oxygen reduction reaction(ORR),the persistent challenge lies in the high onset overpotential of the ORR,and the effect of the elec-trolyte solution cannot be ***,we have systematically investigated the impact of adsorbate species and concentration,as well as solution pH,on the ORR activity on Pt(111)and Pt(poly)*** results all tend to establish a linear quantitative relationship between the onset potential for ORR and the adsorption equilibrium potential of the *** finding indicates the decisive role of adsorbates in the onset potential for ORR,suggesting that the adsorption potential of adsorbates can serve as an intuitive criterion for ORR *** support for this conclusion is derived from experimental results obtained from the oxygen evolution reaction on Pt(poly)with different adsorbate species and from the hydrogen evolution reaction on Pt(111)with iodine *** further propose both an empirical equation for the onset potential for ORR and the concept of a potential-regulated adsor-bate shielding effect to elucidate the influence of adsorbates on ORR *** study provides new insights into the high onset overpotential of the ORR and offers potential strategies for predicting and enhancingORRactivity inthefuture.

关键词： Oxygen reduction reaction Activity Adsorbate Equilibrium potential Pt(111)

Two-stage Planning Method for Energy Router Considering Its Optimal Operation in Distribution Networks

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CSEE Journal of Power and Energy Systems 2024年第2期10卷 605-616页

作者： Meifu Chen Mingchao xia Qifang Chen School of Electrical Engineering Beijing Jiaotong UniversityBeijing 100044China

An energy router can effectively optimize the network loss and power quality of distribution networks. The optimal configuration of the energy router is relatively complex because issues dynamically influence each other, such as the location of the energy router, optimal number and capacity of its ports, and building new distribution lines for the ports. Presently, there has been very few research studies on the practical problems for the energy router. In this paper, a planning model of an energy router combined with the distribution network is established, which fully exploits the active and reactive power control abilities of the energy router to optimize the operation of the grid. The configuration problem is decoupled into two stages. The upper layer determines the location of the energy router and the parameters of the candidate new distribution lines for the ports. The lower layer calculates the optimal configuration of the energy router by minimizing the total annual cost. Because of the same rated bus voltage in the distribution network, the existing structure of the energy router is changed to be more applicable for the distribution network, and then the power flow model of the energy router is also modified. Due to the nonlinearity of the model, the planning model is converted into a mixed-integer second-order cone model to solve efficiently. In addition, some core factors influencing the optimal scheme of the energy router are also analyzed in this paper. Simulation results show that the optimal scheme of the energy router can significantly improve the economic deployment of the energy router, and optimize the network loss and power quality of the distribution network.

关键词： Capacity allocation distribution network energy router optimal operation

Light-based 3D printing of stimulus-responsive hydrogels forminiature devices:recent progress and perspective

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Bio-Design and Manufacturing 2024年第5期7卷 721-746页

作者： Chen Xin Neng xia Li Zhang Department of Mechanical and Automation Engineering The Chinese University of Hong KongHong Kong 999077China Multi-Scale Medical Robotics Center Hong Kong Science ParkShatin NTHong Kong 999077China Chow Yuk Ho Technology Center for Innovative Medicine The Chinese University of Hong KongHong Kong 999077China Department of Surgery The Chinese University of Hong KongHong Kong 999077China CUHK T Stone Robotics Institute The Chinese University of Hong KongHong Kong 999077China

Miniature devices comprising stimulus-responsive hydrogels with high environmental adaptability are now considered competitive candidates in the fields of biomedicine,precise sensors,and tunable *** and advanced fabricationmethods are critical formaximizing the application capabilities ofminiature ***-based three-dimensional(3D)printing technology offers the advantages of a wide range of applicable materials,high processing accuracy,and strong 3D fabrication capability,which is suitable for the development of miniature devices with various *** paper summarizes and highlights the recent advances in light-based 3D-printed miniaturized devices,with a focus on the latest breakthroughs in lightbased fabrication technologies,smart stimulus-responsive hydrogels,and tunable miniature devices for the fields of miniature cargo manipulation,targeted drug and cell delivery,active scaffolds,environmental sensing,and optical ***,the challenges in the transition of tunable miniaturized devices from the laboratory to practical engineering applications are *** opportunities that will promote the development of tunable microdevices are elaborated,contributing to their improved understanding of these miniature devices and further realizing their practical applications in various fields.

关键词： 3D printing Stimulus-responsive hydrogels Miniature devices Shape-morphing

Effects of baffle position in serpentine flow channel on the performance of proton exchange membrane fuel cells

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Chinese Journal of Chemical Engineering 2024年第5期69卷 250-262页

作者： Guodong xia xiaoya Zhang Dandan Ma MOE Key Laboratory of Enhanced Heat Transfer and Energy Conservation Beijing Key Laboratory of Heat Transfer and Energy ConversionBeijing University of TechnologyBeijing 100124China

This study used a three-dimensional numerical model of a proton exchange membrane fuel cell with five types of channels:a smooth channel(Case 1);eight rectangular baffles were arranged in the upstream(Case 2),midstream(Case 3),downstream(Case 4),and the entire cathode flow channel(Case 5)to study the effects of baffle position on mass transport,power density,net power,***,the effects of back pressure and humidity on the voltage were *** showed that compared to smooth channels,the oxygen and water transport facilitation at the diffusion layer-channel interface were added 11.53%-20.60%and 7.81%-9.80%at 1.68 A·cm^(-2)by adding *** closer the baffles were to upstream,the higher the total oxygen flux,but the lower the flux uniformity the worse the water *** oxygen flux of upstream baffles was 8.14%higher than that of downstream baffles,but oxygen flux uniformity decreased by 18.96%at 1.68 A·cm^(-2).The order of water removal and voltage improvement was Case 4>Case 5>Case 3>Case 2>Case *** power of Case 4 was 9.87%higher than that of the smooth *** the Case 4,when the cell worked under low back pressure or high humidity,the voltage increments were *** potential increment for the back pressure of 0 atm was 0.9%higher than that of 2 atm(1 atm=101.325 kPa).The potential increment for the humidity of 100%was 7.89%higher than that of 50%.

关键词： Proton exchange membrane fuel cell Baffle position Mass transfer Net power Uniformity Voltage increment

Evolution of mechanical parameters of Shuangjiangkou granite under different loading cycles and stress paths

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Journal of Rock Mechanics and Geotechnical Engineering 2024年第4期16卷 1113-1126页

作者： Liangjie Gu xia-Ting Feng Rui Kong Chengxiang Yang Yuelin xia Key Laboratory of Ministry of Education on Safe Mining of Deep Metal Mines Northeastern UniversityShenyang110819China State Key Laboratory of Geomechanics and Geotechnical Engineering Institute of Rock and Soil MechanicsChinese Academy of SciencesWuhan430071China

Surrounding rocks at different locations are generally subjected to different stress paths during the process of deep hard rock *** this study,to reveal the mechanical parameters of deep surrounding rock under different stress paths,a new cyclic loading and unloading test method for controlled true triaxial loading and unloading and principal stress direction interchange was proposed,and the evolution of mechanical parameters of Shuangjiangkou granite under different stress paths was studied,including the deformation modulus,elastic deformation increment ratios,fracture degree,cohesion and internal friction ***,stress path coefficient was defined to characterize different stress paths,and the functional relationships among the stress path coefficient,rock fracture degree difference coefficient,cohesion and internal friction angle were *** results show that during the true triaxial cyclic loading and unloading process,the deformation modulus and cohesion gradually decrease,while the internal friction angle gradually increases with increasing equivalent crack *** stress path coefficient is exponentially related to the rock fracture degree difference *** the stress path coefficient increases,the degrees of cohesion weakening and internal friction angle strengthening decrease *** cyclic loading and unloading under true triaxial principal stress direction interchange,the direction of crack development changes,and the deformation modulus increases,while the cohesion and internal friction angle decrease slightly,indicating that the principal stress direction interchange has a strengthening effect on the surrounding ***,the influences of the principal stress interchange direction on the stabilities of deep engineering excavation projects are discussed.

关键词： Triaxial cyclic loading and unloading test Stress path Deformation modulus and elastic deformation increment ratios Fracture degree Cohesion and internal friction angle

Seedless Synthesis of Gold Nanorods with 5–10 nm in Diameters:a Comprehensive Study

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Chemical Research in Chinese Universities 2024年第2期40卷 311-319页

作者： LI Yalan xia Yunsheng Anhui Province Key Laboratory of Biomedical Materials and Chemical Measurement Key Laboratory of Functional Molecular SolidsMinistry of EducationCollege of Chemistry and Materials ScienceAnhui Normal UniversityWuhu241000P.R.China

Small gold nanorods(AuNRs),namely AuNRs with less than 10 nm in diameter,possess a high absorption-to-scattering ratio,a large surface area-to-volume ratio,as well as high cellular uptake *** this study,we systematically investigate seedless synthesis of AuNRs with diameters ranging from 5 nm to 10 *** has been found that several experimental conditions,including the chain length of the used cationic surfactants,and the concentrations of ascorbic acid,NaBH4,and AgNO_(3)can profoundly affect the obtained *** optimal conditions,the production yields of the obtained several AuNRs with different diameters can exceed 90%and even reach almost 100%.The conversion of gold precursors to AuNRs was estimated to be 70%–77%as measured by absorption spectroscopy and inductively coupled plasma mass spectrometry.

关键词： Small gold nanorod Diameter Production yield Conversion rate

母亲孕期农药暴露对子代心脏发育影响的研究现状

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中华围产医学杂志 2018年第12期21卷 840-845页

作者：夏缘青赵克娜李生慧上海交通大学公共卫生学院 200025

本文以杀虫剂、除草剂和杀菌剂等3类农药暴露为重点,综述分析了孕期农药暴露对子代心脏发育的影响及相关机制。研究者检索了截至2018年10月的相关文献共43篇,就农药暴露对子代心脏发育影响的流行病学和基础机制等2方面展开讨论。母亲孕... 详细信息

本文以杀虫剂、除草剂和杀菌剂等3类农药暴露为重点,综述分析了孕期农药暴露对子代心脏发育的影响及相关机制。研究者检索了截至2018年10月的相关文献共43篇,就农药暴露对子代心脏发育影响的流行病学和基础机制等2方面展开讨论。母亲孕期农药暴露可能增大胎儿心血管畸形的发生风险,且不同种类农药暴露与子代不同先天性心脏病亚型有关。其中,证据较为充分的是杀虫剂暴露与房间隔缺损、肺动脉瓣狭窄和室间隔缺损相关,除草剂暴露与大动脉转位和室间隔缺损相关,以及杀菌剂暴露与左心发育不全和主动脉狭窄相关。

关键词：母亲暴露农药环境污染心脏缺损先天性胎儿