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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

Orientational growth behavior and mechanism of delta(δ)phase precipitation in cold-rolled Inconel 718 alloy during heat treatment

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Journal of Iron and Steel Research International 2024年第1期31卷 264-274页

作者： neng-yong Ye Guang-liang Zhang Tian-yue Huang Ming Cheng Shi-hong Zhang Lei Wang School of Materials Science&Engineering Taizhou UniversityTaizhou318000ZhejiangChina Institute of Metal Research Chinese Academy of SciencesShenyang110016LiaoningChina

Due to the important role ofδphase's quantity and morphology in the mechanical and fatigue properties of Inconel 718 alloy and its components,it is necessary to renew insights into the effect of cold deformation on theδphase precipitation,especially on the morphology ***,the nucleation and growth behavior ofδphase in cold-rolled Inconel 718 alloy during aging were *** results show that the precipitation rate and volume fraction ofδphase increase with increasing the cold rolling reduction from 10%to 50%.The volume fraction ofδphase reaches equilibrium after 5 h,remaining at 5.98%,6.52%,and 6.79%under different rolling reductions(10%,30%,and 50%),*** nucleation ofδphase mainly occurs on different sites(grain boundaries,new twin boundaries and old twin boundaries)under 10%rolling reduction,whileδphase mainly nucleates on the new grain boundaries of static recrystallization due to 50%rolling *** the growth ofδphase undergoes a process of alternate orientation growth from spherical(nucleation)→short rod(longitudinal orientation growth)→short rod(radial orientation growth)→dynamic *** 10%rolling reduction,δphase tends to grow into the matrix,while under 50%rolling reduction,the orientation grows faster and is easily affected by the grain boundary curvature.

关键词： Inconel 718 alloy Cold rolling δphase Orientation growth Morphology evolution

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

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

A novel encoding mechanism for particle physics

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Nuclear Science and Techniques 2024年第8期35卷 153-166页

作者： Zhi‑Guang Tan Sheng‑Jie Wang You‑neng Guo Hua Zheng Aldo Bonasera School of Electronic Information and Electrical Engineering Changsha UniversityChangsha 410003China School of Physics and Information Technology Shaanxi Normal UniversityXi’an 710119China Key Laboratory of Quark and Lepton Physics(MOE) Central China Normal UniversityWuhan 430079China Cyclotron Institute Texas A&M UniversityCollege StationTX 77843USA Laboratori Nazionali del Sud INFN95123 CataniaItaly

This study proposes a novel particle encoding mechanism that seamlessly incorporates the quantum properties of particles,with a specific emphasis on constituent *** primary objective of this mechanism is to facilitate the digital registration and identification of a wide range of particle *** design ensures easy integration with different event generators and digital simulations commonly used in high-energy ***,this innovative framework can be easily expanded to encode complex multi-quark states comprising up to nine valence quarks and accommodating an angular momentum of up to 99/*** versatility and scalability make it a valuable tool.

关键词： Multi-quark state Encoding mechanism Constituent quark Particle physics

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

On Stability Discrimination of Limit Cycles for Piecewise Smooth Systems

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Acta Mathematica Sinica,English Series 2024年第7期40卷 1785-1803页

作者： Mao An HAN xia Yu ZHOU School of Mathematical Sciences Zhejiang Normal UniversityJinhua321004P.R.China

This paper is concerned with the problem of stability discrimination of limit cycles for piecewise smooth *** first establish the Poincaré map near a periodic orbit,and deduce the first order derivative of the map for general piecewise smooth systems on the ***,we obtain a sufficient condition for determining the stability of limit cycles for these systems.

关键词： Piecewise smooth system limit cycle stability

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