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Journal of Rare Earths 2024年第1期42卷 116-120,I0004页

作者： Ruipeng qian Yuxuan Ma Fugang Chen hui Sun Yong zhao Yunlong Chen School of Materials Science and Engineering Jiangsu University of Science and TechnologyZhenjiang212003China School of Energy and Power Engineering Jiangsu University of Science and TechnologyZhenjiang212003China

Grain boundary diffusion process(GBDP)has been developed as an effective approach to increase the coercivity of sintered Nd-Fe-B magnets by regulating the compositions and phase distributions near grain *** work aims to explore how to select the optimum annealing temperature after *** this work GBDP was performed on a sintered Nd-Fe-B magnet using Dy_(70)Cu_(30) *** GBDP the low eutectic temperature of the grain boundary phases decreases from the initial 492 to 451℃.The magnetic property dependent on different annealing temperatures near the low eutectic temperature was *** magnetic properties,especially the squareness factor of demagnetization curve show a strong dependence on the annealing *** GBDP the optimal magnetic properties can be obtained after annealing just above the low eutectic temperature of the grain boundary *** mechanism is discussed based on the microstructure analysis.

关键词： Nd-Fe-B magnet Grain boundary diffusion Annealing Dy_(70)Cu_(30)alloy Rare earths

Investigation on cavitating turbulent flow for the twisted NACA66 hydrofoil using a PANS model with helicity modification

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Journal of Hydrodynamics 2024年第2期36卷 219-231页

作者： Chen Geng zhao-hui qian Ke-xin Zheng Wei-xiang Ye Xian-wu Luo State Key Laboratory of Hydroscience cand Engineering Deparment of Energy and Power EngineeringTsinghua UniversityBeijing 100084China Institute of Nuclear and New Energy Technology Tsinghua UniversityBeijing 100084China

In the present paper,the unsteady cavitating turbulent flow over the twisted NACA66 hydrofoil is investigated based on an modified shear stress transfer k-ωpartially averaged Navier-Stokes(MSST PANS)model,i.e.,new MSST PANS(NMSST PANS)model,where the production term of kinetic energy in the turbulence model is modified with *** with the experimental data,cavitation evolution and its characteristic frequency are satisfactorily predicted by the proposed NMSST PANS *** is revealed that the interaction among the main flow,the reentrant jets,and sheet cavitation causes the formation of the primary shedding cavity near the mid-span and the secondary shedding cavity at each side of the twisted hydrofoil,and further induces the remarkable pressure gradient around shedding *** with the development of the primary and the secondary shedding cavities,the great pressure gradient associated with large cavity volume variation promotes the vortical flow generation and the spatial deformation of vortex structure during cavitation evolution,and results in the primary and the secondary U-type ***,dynamic mode decomposition(DMD)analysis is utilized to confirm the interaction among the main flow,the main reentrant jet and two side reentrant jets,and *** results indicate that the proposed NMSST PANS model is suitable to simulate the complicated cavitating turbulent flow for various engineering applications.

关键词： Cavitating turbulent flow partially averaged Navier-Stokes(PANS)model hydrofoil numerical simulation

Molecular composition of naphthenic acids in a Chinese heavy crude oil and their impacts on oil viscosity

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Petroleum Science 2023年第2期20卷 1225-1230页

作者： qian-hui zhao Shuai M Jian-Xun Wu Wei-Feng Chang Sheng-Fei Zhang Xin-Ge Sun Bing Zhou Zeng-Min Lun Keng H.Chung Quan Shi State Key Laboratory of Shale Oil and Gas Enrichment Mechanisms and Effective Development Sinopec Petroleum Exploration and Production Research InstituteBeijing 100083China State Key Laboratory of Heavy Oil Processing Petroleum Molecular Engineering Center(PMEC)China University of PetroleumBeijing 102249China Research Institute of Petroleum Exploration and Development CNPCBeijing 100083China Xinjiang Oilfield Company CNPCKaramayXinjiang 834000China Well Resources Inc. EdmontonCanada

Most heavy crude oils underwent biodegradation and generated a significant amount of naphthenic acids. Naphthenic acids are polar compounds with the carboxylic group and are considered as a major factor affecting the oil viscosity. However, the relationship between the molecular composition of naphthenic acids and oil viscosity is not well understood. This study examined a “clean” heavy oil with low contents of heteroatoms but had a high content of naphthenic acids. Naphthenic acids were fractionated by distillation and caustic extraction. The molecular composition was characterized by high-resolution Orbitrap mass spectrometry. It was found that the 2- and 3-ring naphthenic monoacids with 15–35 carbon atoms are dominant components of the acid fractions;the caustic extraction is capable of isolating naphthenic acids with less than 35 carbons, which is equivalent to the upper limit of the distillable components, but not those in the residue fraction;the total acid number of the heavy distillates is higher than that of the residue fraction;the viscosity of the distillation fraction increases exponentially with an increased boiling point of the distillates. Blending experiments indicates that there is a strong correlation between the oil viscosity and acids content, although the acid content is only a few percent of the total oil.

关键词： Heavy crude oil Viscosity High-resolution mass spectrometer Naphthenic acid

Complex interactions among insect viruses-insect vector-arboviruses

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Insect Science 2024年第3期31卷 683-693页

作者： hui Wang qian Chen Taiyun Wei State Key Laboratory of Ecological Pest Control for Fujian and Taiwan Crops Vector-borne Virus Research CenterFujian Agriculture and ForestryUniversityFuzhouChina

Insects are the host or vector of diverse viruses including those that infect vertebrates,plants,and *** viruses reside inside their insect hosts and are vertically transmitted from parent to *** insect virus-host relationship is intricate,as these viruses can impact various aspects of insect biology,such as development,reproduction,sex ratios,and ***-borne viruses(arboviruses)that cause substantial global health or agricultural problems can also be vertically transmitted to insect vector *** infections with insect viruses and arboviruses are common in *** coinfections involve complex interactions,including synergism,dependence,and *** studies have shed light on the influence of insect viruses on the competence of insect vectors for *** this review,we focus on the biological effects of insect viruses on the transmission of arboviruses by *** also discuss the potential mechanisms by which insect viruses affect the ability of hosts to transmit arboviruses,as well as potential strategies for disease control through manipulation of insect *** of the interactions among insect vectors,insect viruses and arboviruses will provide new opportunities for development of innovative strategies to control arbovirus transmission.

关键词： arbovirus insect biology insect vectors insect virus interaction transmission

Modulating the alloying mode in the doping-induced synthesis of Au-Pd nanowires

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Nano Research 2024年第4期17卷 3334-3343页

作者： hui Jin Xiaoliang Wei Lecheng zhao Jialong Yu Qiao Pan Shumin Li qian Wang zhaotong Yuan Dan Yang Donghui zhao Hongyu Chen Yawen Wang Institute of Advanced Synthesis School of Chemistry and Molecular EngineeringJiangsu National Synergistic Innovation Center for Advanced MaterialsNanjing Tech UniversityNanjing 211816China School of Science Westlake UniversityHangzhou 310064China Institute of Natural Sciences Westlake Institute for Advanced StudyHangzhou 310064China

Heterogeneous doping is one effective strategy for synthesizing metal alloy ***,the heterogeneous doping processes of Pd on the ultrathin Au nanowires were systematically modulated and ***-Pd alloy nanowires with various morphologies and lattice structures can be obtained by adjusting the morphology of the precursor Au nanowires and the kinetics of the heterogeneous doping *** effects of the rate of Pd reduction and the concentration of the ligand oleylamine(OAm)on the Pd deposition and alloying mode were ***,as the Pd deposition rate decreases,the Pd deposition and alloying mode switches from the island-forming Stransky–Krastanov(SK)mode to the epitaxial Frank-van der Merwe(FM)mode,and eventually to an unconventional twisting alloying mode,where the interdiffusion of Pd and Au causes drastic rearrangement of the lattice structure and formation of helical *** kinetics-related variation of alloying mode could also be observed in the Au-Ag nanowires,demonstrating a general design principle for the synthesis of alloy *** addition,the electrocatalytic performance of various Au-Pd nanowires was evaluated,and the alloy nanowire formed via the SK mode was found to be an excellent electrocatalyst for oxygen reduction and ethanol oxidation.

关键词： gold nanowires Au-Pd alloy oleylamine post-synthetic modification

Principal components of nuclear mass models

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Science China(Physics,Mechanics & Astronomy) 2024年第7期67卷 65-71页

作者： Xin-hui Wu Pengwei zhao Department of Physics Fuzhou UniversityFuzhou 350108China State Key Laboratory of Nuclear Physics and Technology School of PhysicsPeking UniversityBeijing 100871China

Principal component analysis(PCA)is employed to extract the principal components(PCs)present in nuclear mass models for the first *** effects from different nuclear mass models are reintegrated and reorganized in the extracted *** PCs are recombined to build new mass models,which achieve better accuracy than the original theoretical mass *** comparison indicates that using the PCA approach,the effects contained in different mass models can be collaborated to improve nuclear mass predictions.

关键词： nuclear mass principal component analysis nuclear models statistical methods

Vasculopathy in dermatomyositis

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Chinese Medical Journal 2024年第2期137卷 247-249页

作者： hui Xu Jie qian Department of Rheumatology Affiliated Hospital of Nantong UniversityNantongJiangsu 226001China

To the Editor:Dermatomyositis(DM)is a rare autoimmune disease characterized by specific cutaneous manifestations and proximal muscle weakness,in which abnormalities of nailfold capillary(NFC)and serum levels of vascular biomarkers are *** changes in vascular lesions play an important role in the occurrence and development of DM and reflect the disease activity and treatment *** to the diversity of clinical manifestations in DM patients,vascular involvement is often under-evaluated,causing the treatment of refractory vascular damage *** review aims to explore the mechanisms,clinical manifestations,and treatment options of vasculopathy in DM to achieve early recognition and improve prognosis.

关键词： involvement clinical myositis

In situ synthesis of porous Pt-Pd bimetallic structures for sweat glucose biosensing using dynamic hydrogen bubble template method

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Rare Metals 2024年第7期43卷 3408-3414页

作者： Yi-Wen Guo qian-hui Wei Fei Wei Hao Liu Hong-Bin zhao Dong Wang Hai-Ling Tu State Key Laboratory of Advanced Materials for Smart Sensing China GRINM Group Co.Ltd. Department of Advanced Electronic Materials GRIMAT Engineering Institute Co.Ltd. General Research Institute for Nonferrous Metals GRINM (Guangdong) Institute for Advanced Materials and Technology School of Chemical Engineering Northeast Electric Power University

For the practical application of sweat glucose biosensors,it is crucial to develop a method for modifying the working electrode with noble metals that ensures strong *** this study,we synthesized porous Pt-Pd bimetall... 详细信息

关键词： Hydrogen

Probabilistic seismic inversion based on physics-guided deep mixture density network

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Petroleum Science 2024年第3期21卷 1611-1631页

作者： qian-Hao Sun zhao-Yun Zong Xin Li National Key Laboratory of Deep Oil and Gas China University of Petroleum(East China)Qingdao266580ShandongChina Laoshan Laboratory Qingdao266580ShandongChina CNOOC Research Institute Ltd. Beijing100028China

Deterministic inversion based on deep learning has been widely utilized in model parameters *** by logging data,seismic data,wavelet and modeling operator,deterministic inversion based on deep learning can establish nonlinear relationships between seismic data and model ***,seismic data lacks low-frequency and contains noise,which increases the non-uniqueness of the *** conventional inversion method based on deep learning can only establish the deterministic relationship between seismic data and parameters,and cannot quantify the uncertainty of *** order to quickly quantify the uncertainty,a physics-guided deep mixture density network(PG-DMDN)is established by combining the mixture density network(MDN)with the deep neural network(DNN).Compared with Bayesian neural network(BNN)and network dropout,PG-DMDN has lower computing cost and shorter training time.A low-frequency model is introduced in the training process of the network to help the network learn the nonlinear relationship between narrowband seismic data and low-frequency *** addition,the block constraints are added to the PG-DMDN framework to improve the horizontal continuity of the inversion *** illustrate the benefits of proposed method,the PG-DMDN is compared with existing semi-supervised inversion *** synthetic data examples of Marmousi II model are utilized to quantify the influence of forward modeling part,low-frequency model,noise and the pseudo-wells number on inversion results,and prove the feasibility and stability of the proposed *** addition,the robustness and generality of the proposed method are verified by the field seismic data.

关键词： Deep learning Probabilistic inversion Physics-guided Deep mixture density network

Toward a rapid and convenient nanoplastic quantification method in laboratory-scale study based on fluorescence intensity

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Frontiers of Environmental Science & Engineering 2024年第5期18卷 117-126页

作者： Ruiqi Yan Sen Lin qian Ding Lei Zhang Xia Yu Wentao zhao qian Sui State Environmental Protection Key Laboratory of Environmental Risk Assessment and Control on Chemical Process School of Resources and Environmental EngineeringEast China University of Science and TechnologyShanghai200237China State Key Laboratory of Pollution Control and Resource Reuse College of Environmental Science and EngineeringTongji UniversityShanghai200092China Shanghai Institute of Pollution Control and Ecological Security Shanghai200092China

The thorough investigation of nanoplastics(NPs)in aqueous environments requires efficient and expeditious quantitative analytical methods that are sensitive to environmentally relevant NP concentrations and convenient to *** analysis-based quantitative methods have been acknowledged as effective and rapid approaches for quantifying NP concentrations in laboratory-scale ***,we compared three commonly used optical response indicators,namely fluorescence intensity(FI),ultraviolet absorbance,and turbidity,to assess their performance in quantifying ***,orthogonal experiments were conducted to evaluate the influence of various water quality parameters on the preferred indicator-based quantification *** results revealed that FI exhibits the highest correlation coefficient(>0.99)with NP ***,the limit of quantification(LOQ)for various types of NPs is exceptionally low,ranging from 0.0089 to 0.0584 mg/L in ultrapure water,well below environmentally relevant *** variations in water quality parameters such as pH,salinity,suspended solids(SS),and humic acid,a robust relationship between detectable FI and NP concentration was ***,an increased matrix,especially SS in water samples,results in an enhanced LOQ for ***,the quantitative method remains applicable in real water bodies,especially in drinking water,with NP LOQ as low as 0.0157–0.0711 mg/*** exceeds the previously reported detectable concentration for 100 nm NPs at 40µg/mL using surface-enhanced Raman *** study confirms the potential of FI as a reliable indicator for the rapid quantification of NPs in aqueous environments,offering substantial advantages in terms of both convenience and cost-effectiveness.

关键词： Nanoplastic quantification Fluorescence intensity Drinking water Limit of quantification(LOQ) Matrix effects