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Nano Research 2024年第8期17卷 6870-6878页

作者： Dongming Chen Weixin zhao Zihao Xu Zheng zhao Juanyu Yang Yongke Hou Yongqi Zhang Zongyu feng Meisheng Cui Xiaowei Huang National Engineering Research Center for Rare Earth Grirem Advanced Materials Co.Ltd.Beijing 100088China Grirem Hi-Tech Co. Ltd.Sanhe 065201China General Research Institute for Nonferrous Metals Beijing 100088China

With the continuous tightening of automotive emission regulations and the increasing promotion of energy-efficient hybrid vehicles,new challenges have arisen for the low-temperature performance of three-way catalysts(TWCs).To guide the design of next-generation TWCs,it is essential to further develop our understanding of the relationships between microstructure and catalytic ***,Rh/CeO_(2)–ZrO_(2) catalysts were synthesized with different Rh metal dispersion by using a combination of the wet impregnation method and reduction *** catalysts included Rh single-atom catalysts,cluster catalysts,and nanoparticle *** results showed that the Rh nanoparticle catalyst,with an average size of 1.9 nm,exhibited superior three-way catalytic performance compared to the other *** on the catalytic activity in a series of simple reaction atmospheres such as CO+O_(2),NO+CO,and hydrocarbons(HCs)+O_(2) and operando infrared spectroscopy,we found that metallic Rh sites on Rh nanoparticles are the key factor responsible for the low-temperature catalytic performance.

关键词： Rh/CeO_(2)-ZrO_(2) catalyst Rh metal size effect Rh nanoparticles three-way catalytic performance

Longitudinal changes in body weight of breastfeeding mothers in the first year after delivery and its relationship with human milk composition:a combined longitudinal and cross-sectional cohort study

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Food Science and Human Wellness 2024年第1期13卷 254-264页

作者： Huijuan Ruan Yajie Zhang Qingya Tang Xuan zhao Xuelin zhao Yi Xiang Wei Geng Yi feng Wei Cai Department of Clinical Nutrition Xinhua Hospital Affiliated to Shanghai Jiao Tong University School of MedicineShanghai 200092China Shanghai Key Laboratory of Pediatric Gastroenterology and Nutrition Shanghai Institute of Pediatric ResearchShanghai 200092China Department of Pediatric Surgery Xinhua Hospital Affiliated to Shanghai Jiao Tong University School of MedicineShanghai 200092China

Objective:Postpartum weight retention(PPWR)is a common problem among women after *** main objectives of this study are to understand the changes in body weight of breastfeeding mothers during long-term follow-up and preliminarily explore the relationship between maternal body weight and human milk composition,including macronutrients,leptin,and ***:The study included a longitudinal cohort(122 mothers),and a cross-sectional cohort(37 mothers).The human milk,maternal weight,and dietary surveys were collected in the longitudinal cohort at different follow-up time points(1-14 days postpartum,2-4 months postpartum,5-7 months postpartum,and 12-17 months postpartum).The maternal body weight was analyzed using the responses in the survey questionnaires.A milk analyzer based on the mid-infrared spectroscopy(MIRS)was used to determine milk composition,and nutrition analysis software evaluated dietary *** the cross-sectional cohort,participating mothers were asked to provide blood and human milk samples and pertinent information related to maternal body *** body composition was measured by bioelectrical impedance analysis(BIA),while ELISA analyzed leptin and adiponectin in milk and ***:At 5-7 months postpartum,the PPWR of breastfeeding mothers was(2.46±3.59)*** 12-17 months postpartum,the PPWR was(0.98±4.06)*** was found to be negatively correlated with milk fat content within 14 days postpartum and positively correlated at 2-4 months *** addition,the maternal weight and body muscle mass were positively correlated with leptin and adiponectin in *** leptin was positively correlated with the mother’s body weight,body mass index(BMI),FAT percentage,and body fat mass,while plasma adiponectin did not correlate with any *** results also indicate that the PPWR did not correlate with leptin and adiponectin in plasma or ***:Breastfeeding mothers may retain considerable weight gai

关键词： Human milk Milk composition Body weight Body mass index(BMI) Weight gain Postpartum weight retention

Probabilistic modeling of multifunction radars with autoregressive kernel mixture network

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Defence Technology（防务技术） 2024年第5期35卷 275-288页

作者： Hancong feng Kaili.Jiang Zhixing Zhou Yuxin zhao Kailun Tian Haixin Yan Bin Tang School of Information and Communication Engineering University of Electronic Science and Technology of ChinaChengdu 611731China

The task of modeling and analyzing intercepted multifunction radars(MFRs)pulse trains is vital for cognitive electronic *** methodologies predominantly rely on prior information or heavily constrained models,posing challenges for non-cooperative *** paper introduces a novel approach to model MFRs using a Bayesian network,where the conditional probability density function is approximated by an autoregressive kernel mixture network(ARKMN).Utilizing the estimated probability density function,a dynamic programming algorithm is proposed for denoising and detecting change points in the intercepted MFRs pulse *** results affirm the proposed method's efficacy in modeling MFRs,outperforming the state-of-the-art in pulse train denoising and change point detection.

关键词： Probabilistic forecasting Multifunction radar Unsupervised learning Change point detection Outlier detection

Decreasing productivity of pine forests on the southern edge of the Mongolian Plateau as indicated by tree rings

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Journal of Forestry Research 2024年第5期35卷 171-181页

作者： Zhuolan Shen Shijie Wang feng Chen Heli Zhang Xiaoen zhao Youping Chen Mao Hu Yunnan Key Laboratory of International Rivers and Transboundary Eco‑Security Institute of International Rivers and Eco‑SecurityYunnan UniversityKunming 650500People’s Republic of China Southwest United Graduate School Kunming 650500People’s Republic of China Key Laboratory of Tree-Ring Physical and Chemical Research of China Meteorological Administration/Xinjiang Laboratory of Tree-Ring Ecology Institute of Desert MeteorologyChina Meteorological AdministrationÜrümqi 830002People’s Republic of China

Vegetation productivity on the southern edge of the Inner Mongolian Plateau,which plays a vital role in the ecological environment and in the arable and pasto-ral production in this region,can be characterized by the NDVI(normalized difference vegetation index).However,the observed NDVI data span only the last~40 *** growth of Pinus tabulaeformis *** strongly correlated with the NDVI,making it a valuable proxy for extend-ing the length of observed NDVI *** this study,we reconstructed an NDVI series for 1776–2021 for the Daqing Mountains,based on a tree-ring width *** reconstructed data accounted for 55%of the variance in the observed data,and its statistical characteristics and validation indicate that the reconstruction is *** correlation analysis demonstrated the consistency of climate signals in central Inner Mongolia in both the arable and pastoral *** results of superposed epoch analysis revealed a good temporal consistency between drought and flood events and the reconstructed NDVI sequence in this region.

关键词： Drought Semi-arid area Peru current Yinshan Mountains

Effect of Mn content on microstructure and properties of AlCrCuFeMnx high-entropy alloy

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China Foundry 2024年第2期21卷 147-158页

作者： Ning Wang Kai Ma Qiu-da Li Yu-dong Yuan Yan-chun zhao Li feng School of Materials Science and Engineering Lanzhou University of TechnologyLanzhou 730050China State Key Laboratory of Advanced Processing and Reuse of Nonferrous Metals Lanzhou 730050China CNNC Nuclear Power Operation and Management Co. Ltd.Haiyan 314300ZhejiangChina

AlCrCuFeMnx(x=0,0.5,1,1.5,and 2)high-entropy alloys were prepared using the vacuum arc melting *** microstructure and mechanical properties of AlCrCuFeMnxwere analyzed and tested by XRD,SEM,TEM,nanoindentation,and electronic universal *** results indicate that the AlCrCuFeMnxhigh-entropy alloy exhibits a dendritic structure,consisting of dendrites with a BCC structure,interdendrite regions with an FCC structure,and precipitates with an ordered BCC structure that form within the ***(Mn)has a strong affinity for dendritic,interdendritic,and precipitate structures,allowing it to easily enter these *** an increase in Mn content,the size of the precipitated nanoparticles in the dendritic region initially increases and then ***,the area fraction initially decreases and then ***,the alloy’s strength and wear resistance decrease,while its plasticity *** Al Cr Cu Fe Mn1.5alloy boasts excellent mechanical properties,including a hardness of 360 HV and a wear rate of 2.4×10^(-5)mm^(3)·N^(-1)·mm^(-1).It also exhibits impressive yield strength,compressive strength,and deformation rates of 960 MPa,1,700 MPa,and 27.5%,respectively.

关键词： high-entropy alloys microstructure mechanical properties wear resistance strengthening mechanisms

A multifunctional shear apparatus for rocks subjected to true triaxial stress and high temperature in real-time

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Journal of Rock Mechanics and Geotechnical Engineering 2024年第9期16卷 3524-3543页

作者： Jun zhao Xia-Ting feng Jia-Rong Wang Liang Hu Yue Guo Key Laboratory of Ministry of Education on Safe Mining of Deep Metal Mines Northeastern UniversityShenyang110819China Key Laboratory of Liaoning Province on Deep Engineering and Intelligent Technology Northeastern UniversityShenyang110819China

Deep engineering disasters,such as rockbursts and collapses,are more related to the shear slip of rock joints.A novel multifunctional device was developed to study the shear failure mechanism in *** this device,the complete shearedeformation process and long-term shear creep tests could be performed on rocks under constant normal stiffness(CNS)or constant normal loading(CNL)conditions in real-time at high temperature and true-triaxial *** the research and development process,five key technologies were successfully broken through:(1)the ability to perform true-triaxial compressioneshear loading tests on rock samples with high stiffness;(2)a shear box with ultra-low friction throughout the entire stress space of the rock sample during loading;(3)a control system capable of maintaining high stress for a long time and responding rapidly to the brittle fracture of a rock sample as well;(4)a refined ability to measure the volumetric deformation of rock samples subjected to true triaxial shearing;and(5)a heating system capable of maintaining uniform heating of the rock sample over a long *** developing these technologies,loading under high true triaxial stress conditions was *** apparatus has a maximum normal stiffness of 1000 GPa/m and a maximum operating temperature of 300*** differences in the surface temperature of the sample are constant to within5*** types of true triaxial shear tests were conducted on homogeneous sandstone to verify that the apparatus has good performance and *** results show that temperature,lateral stress,normal stress and time influence the shear deformation,failure mode and strength of the *** novel apparatus can be reliably used to conduct true-triaxial shear tests on rocks subjected to high temperatures and stress.

关键词： True-triaxial shear apparatus Rocks Complete shear stressedeformation process Creep Real-time high-temperature

Pd/N-doped carbon dots@dendritic mesoporous silica nanospheres:A highly efficient catalyst for the hydrogenation of 4-nitrophenol

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Nano Research 2024年第9期17卷 7967-7974页

作者： Weiruo Liu Yanbin Zhu Jiwei Wang Haisong feng Yunpu Zhai Wei Li Dongyuan zhao College of Chemistry Zhengzhou University100 Kexue AvenueZhengzhou 450001China Department of Chemistry Laboratory of Advanced MaterialsShanghai Key Laboratory of Molecular Catalysis and Innovative Materialsand State Key Laboratory of Molecular Engineering of PolymersFudan UniversityShanghai 200433China State Key Laboratory of Chemical Resource Engineering Beijing Advanced Innovation Center for Soft Matter Science and EngineeringBeijing University of Chemical TechnologyBeijing 100029China

Highly dispersed Pd/N-doped carbon dots(Pd/NCDs)were successfully immobilized in the mesoporous channels of amino-functionalized dendritic mesoporous silica nanospheres(NMS).The synthesized Pd/NCDs@NMS catalyst exhibits outstanding performance in the catalytic reduction of 4-nitrophenol(4-NP),achieving a turnover frequency of 1461.8 mol·molPd^(-1)·h^(-1),with the conversion rate remaining above 80%after 11 *** and density functional theory calculations reveal that the NCDs significantly affect the electronic structure of Pd nanoparticles,leading to changes in the energy barriers for the adsorption of 4-NP at the Pd sites and the conversion of 4-NP reaction intermediates,which is a key factor contributing to the catalytic *** study offers a new strategy for synthesizing carbon-dot-modified metal-based catalysts.

关键词： palladium nanoparticles nitrogen-doped carbon dots dendritic mesoporous silica catalytic hydrogenation 4-nitrophenol reduction

Effect of Phase Separation Size on the Properties of Self-healing Elastomer

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Chinese Journal of Polymer Science 2024年第6期42卷 798-804页

作者： Jun Xu Lei Zhu Xian-Qi feng Cong Sui Wen-Peng zhao Shou-Ke Yan School of Chemical Engineering Qingdao University of Science&TechnologyQingdao266042China College of Engineering Yanching institute of TechnologyLangfang065210China Key Laboratory of Rubber-plastics Qingdao University of Science&TechnologyQingdao266042China State Key Laboratory of Chemical Resource Engineering Beijing University of Chemical TechnologyBeijing100029China

Regulation of phase structure has been recognized as one of the most effective ways to fabricate self-healing polymers with high mechanical *** mechanical properties of the resultant polymers are certainly affected by the size of separated phase ***,the study on this aspect is absence,because it can hardly exclude the influence of variation in monomer proportion required for tuning the separated phase ***,we report the first study on tuning the phase size through reversible addition-fragmentation chain transfer(RAFT)polymerization without changing the proportion of *** expected,the size of separated phase has been successfully mediated from 15 nm to 9 nm by tuning the molecular weight of the chain transfer *** is found that the mechanical strength and the self-healing efficiency of the resultant polymers increase simultaneously with the decrease of phase *** study on the formation kinetics of hydrogen bonds reveals that the decrease of phase size can facilitate the re-bonding rate of hydrogen bonds,even if the migration of polymer chains is restricted.

关键词： Self-healing polymers Phase separation Reversible addition-fragmentation chain transfer

Interfacial Electronic Modulation of Dual-Monodispersed Pt–Ni_(3)S_(2) as Efficacious Bi-Functional Electrocatalysts for Concurrent H_(2) Evolution and Methanol Selective Oxidation

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Nano-Micro Letters 2024年第4期16卷 415-431页

作者： Qianqian zhao Bin zhao Xin Long Renfei feng Mohsen Shakouri Alisa Paterson Qunfeng Xiao Yu Zhang Xian‑Zhu Fu Jing‑Li luo Shenzhen Key Laboratory of Energy Electrocatalytic Materials Shenzhen Key Laboratory of Polymer Science and TechnologyGuangdong Research Center for Interfacial Engineering of Functional MaterialsCollege of Materials Science and EngineeringShenzhen UniversityShenzhen 518060People’s Republic of China Canadian Light Source Inc. SaskatoonSK S7N 0X4Canada Instrumental Analysis Center of Shenzhen University(Lihu Campus) Shenzhen UniversityShenzhen 518055People’s Republic of China

Constructing the efficacious and applicable bifunctional electrocatalysts and establishing out the mechanisms of organic electro-oxidation by replacing anodic oxygen evolution reaction(OER) are critical to the development of electrochemicallydriven technologies for efficient hydrogen production and avoid CO_(2) emission. Herein, the hetero-nanocrystals between monodispersed Pt(~ 2 nm) and Ni_(3)S_(2)(~ 9.6 nm) are constructed as active electrocatalysts through interfacial electronic modulation, which exhibit superior bi-functional activities for methanol selective oxidation and H_(2) generation. The experimental and theoretical studies reveal that the asymmetrical charge distribution at Pt–Ni_(3)S_(2) could be modulated by the electronic interaction at the interface of dual-monodispersed heterojunctions, which thus promote the adsorption/desorption of the chemical intermediates at the interface. As a result, the selective conversion from CH_(3)OH to formate is accomplished at very low potentials(1.45 V) to attain 100 m A cm^(-2) with high electronic utilization rate(~ 98%) and without CO_(2) emission. Meanwhile, the Pt–Ni_(3)S_(2) can simultaneously exhibit a broad potential window with outstanding stability and large current densities for hydrogen evolution reaction(HER) at the cathode. Further, the excellent bi-functional performance is also indicated in the coupled methanol oxidation reaction(MOR)//HER reactor by only requiring a cell voltage of 1.60 V to achieve a current density of 50 m A cm^(-2) with good reusability.

关键词： Dual-monodispersed heterostructure Electronic interactive modulation Reaction mechanism Methanol oxidation reaction Hydrogen generation

An improved deep dilated convolutional neural network for seismic facies interpretation

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Petroleum Science 2024年第3期21卷 1569-1583页

作者： Na-Xia Yang Guo-Fa Li Ting-Hui Li Dong-feng zhao Wei-Wei Gu State Key Laboratory of Petroleum Resources and Engineering CNPC Key Lab of Geophysical ExplorationChina University of Petroleum(Beijing)Beijing 102249China Dagang Branch Research InstituteBGPTianjin300280China

With the successful application and breakthrough of deep learning technology in image segmentation,there has been continuous development in the field of seismic facies interpretation using convolutional neural *** intelligent and automated methods significantly reduce manual labor,particularly in the laborious task of manually labeling seismic ***,the extensive demand for training data imposes limitations on their wider *** overcome this challenge,we adopt the UNet architecture as the foundational network structure for seismic facies classification,which has demonstrated effective segmentation results even with small-sample training ***,we integrate spatial pyramid pooling and dilated convolution modules into the network architecture to enhance the perception of spatial information across a broader *** seismic facies classification test on the public data from the F3 block verifies the superior performance of our proposed improved network structure in delineating seismic facies *** analysis against the traditional UNet model reveals that our method achieves more accurate predictive classification results,as evidenced by various evaluation metrics for image ***,the classification accuracy reaches an impressive 96%.Furthermore,the results of seismic facies classification in the seismic slice dimension provide further confirmation of the superior performance of our proposed method,which accurately defines the range of different seismic *** approach holds significant potential for analyzing geological patterns and extracting valuable depositional information.

关键词： Seismic facies interpretation Dilated convolution Spatial pyramid pooling Internal feature maps Compound loss function