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Particuology 2024年第1期84卷 45-52页

作者： le-le Zhang lei Tong Yanwei Ding Wanqun Zhang Hai-Wei Liang Hefei National Research center for Physical Sciences at the microsc.le Department of ChemistryUniversity of Science and Technology of ChinaHefei230026China

Hierarchically porous carbons(HPcs)with multimodal pores have attracted considerable attention due to their unique physical and chemical properties and various application potentials in heterogeneous catalysis,environmental treatment,and energy storage and ***,we report a general and simple zinc salts-assisted method for the synthesis of HPcs with varied porosity and chemical func-tionalities by the direct carbonization of diverse biomass and *** the carbonization,zinc salts are thermally decomposed into nanoparticles that serve as in-situ templates to introduce nanopores in *** prepared HPcs exhibit high specific surface areas(up to 2432 m2 g-1),large pore volumes(up to 4.30 cm^(3)g^(-1)),and broad pore size ***,the zinc salts can be recovered and recycled,supporting the sustainable production of HPcs on large *** prepared HPcs-supported catalysts with atomically dispersed metal sites exhibit promising electrocatalytic performance for the oxygen reduction reaction.

关键词： Hierarchical porous carbon Zinc salts Biomass Wastes Electrocatalysis

contrasting physical mechanisms of yellowfin tuna fluctuations between the western and eastern Indian Ocean

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Journal of Oceanology and Limnology 2024年第3期42卷 960-971页

作者： Peng LIAN le GAO Key Laboratory of Ocean Observation and Forecasting and Key Laboratory of Ocean circulation and Waves Institute of OceanologyChinese Academy of SciencesQingdao 266071China University of chinese Academy of Sciences Beijing 100049China Laboratory for Ocean Dynamics and climate Laoshan LaboratoryQingdao 266061China

As an economically critical pelagic migratory species,yellowfin tuna(Thunnus albacores,YFT)is very sensible to physical and environmental conditions,such as sea surface temperature(SST),ocean heat content(OHc),and the mixed layer depth(mLD).We investigated the impact of SST,OHc,and mLD on fluctuations of YFT catch in the western/eastern Indian Ocean using the long time series of 63-year environmental and YFT *** found that the impact of SST on YFT was heavily overestimated in the past,and mLD plays a more critical role in the YFT catch *** the mLD deepens(>34.8 m),SST was more influential in predicting the catches of YFT than OHc in the western Indian Ocean,and OHc was more critical to YFT than SST in the eastern Indian ***,when the mLD shallows(m),mLD was more vital to predict the catch per unit effort(cPUE)of YFT than SST/OHc in the *** 2000,there was an asynchronous pattern of YFT cPUE induced by higher frequency variations and ocean hiatus of SST/OHc signals in the western and eastern Indian Oceans *** impact of the subsurface hiatus may induce the decrease of YFT in the eastern Indian *** above findings clarified a non-stationary relationship between the environmental factors and catches of YFT and provided new insights into variations in YFT abundance.

关键词： yellowfin tuna Indian Ocean sea surface temperature(SST) ocean heat content(OHc) mixed layer depth(mLD) hiatus

A comprehensive Survey of Recent Transformers in Image,Video and Diffusion models

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computers, materials & continua 2024年第7期80卷 37-60页

作者： Dinh Phu cuong le Dong Wang Viet-Tuan le college of computer Science and Electronic Engineering Hunan UniversityChangsha410082China Faculty of Information Technology Yersin University of Da LatDa Lat66100Vietnam Faculty of Information Technology Ho Chi Minh City Open UniversityHo Chi Minh City722000Vietnam

Transformer models have emerged as dominant networks for various tasks in computer vision compared to convolutional Neural Networks(cNNs).The transformers demonstrate the ability to model long-range dependencies by utilizing a self-attention *** study aims to provide a comprehensive survey of recent transformerbased approaches in image and video applications,as well as diffusion *** begin by discussing existing surveys of vision transformers and comparing them to this ***,we review the main components of a vanilla transformer network,including the self-attention mechanism,feed-forward network,position encoding,*** the main part of this survey,we review recent transformer-based models in three categories:Transformer for downstream tasks,Vision Transformer for Generation,and Vision Transformer for *** also provide a comprehensive overview of recent transformer models for video tasks and diffusion *** compare the performance of various hierarchical transformer networks for multiple tasks on popular benchmark ***,we explore some future research directions to further improve the field.

关键词： Transformer vision transformer self-attention hierarchical transformer diffusion models

comparison of Treatment Efficacy of Different Number of Botulinum Toxin Type A Injection Sites for crow's Feet Lines: A Single-center Retrospective clinical Study in Vietnam

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International Journal of Dermatology and Venereology 2024年第3期7卷 131-136页

作者： Nguyen Quang m. le Thi m. Duong Phuc H. Vu Thai H. le Huu D. Department of Stem cell Research and Application National Hospital of Dermatology and Venereology Hanoi 100000 Viet Nam Department of Healthcare Activity Direction National Hospital of Dermatology and Venereology Hanoi 100000 Viet Nam Department of Dermatology Hanoi Medical University Hanoi 100000 Viet Nam

Objective: Botulinum toxin type A is frequently used to treat crow's feet lines. However, the optimal dose and injection sites are still controversial. The objective of this study was to compare the efficacy of different botulinum toxin type A injection patterns for the treatment of crow's feet. methods: This single-center, retrospective, clinical study was conducted at the National Hospital of Dermatology and Venereology from July 2020 to December 2020. Data on 60 patients with crow's feet were collected and divided into 2 groups (3- or 4-point intramuscular injection) according to the intramuscular injection technique the patients received. The treatment efficacy was assessed based on the changes in the crow's Feet Grading Sc.le score at 1, 4, and 16 weeks after treatment. Repeated measures analysis of variance was used for the assessment of changes in scores over time between the two groups. Results: After treatment, the average crow's Feet Grading Sc.le score was significantly decreased compared with the pretreatment score at all timepoints (1, 4, and 16 weeks) in both states (dynamic: For 3-point intramuscular injection technique, 1 week: 1.90 ± 0.71 vs. 2.97 ± 0.56; 4 weeks: 1.87 ± 0.68 vs. 2.97 ± 0.56; 16 weeks: 2.60 ± 0.67 vs. 2.97 ± 0.56. For 4-point intramuscular injection technique, 1 week: 1.73 ± 0.83 vs. 3.03 ± 0.49; 4 weeks: 1.73 ± 0.74 vs. 3.03 ± 0.49; 16 weeks: 2.57 ± 0.68 vs. 3.03 ± 0.49, all P c: For 3-point intramuscular injection technique, 1 week: 1.20 ± 0.89 vs. 2.20 ± 0.85; 4 weeks: 1.20 ± 0.89 vs. 2.20 ± 0.85; 16 weeks: 1.87 ± 0.97 vs. 2.20 ± 0.85; For 4-point intramuscular injection technique, 1 week: 1.50 ± 0.86 vs. 2.30 ± 0.84; 4 weeks: 1.33 ± 0.84 vs. 2.30 ± 0.84; 16 weeks: 1.87 ± 0.97 vs. 2.30 ± 0.84. All P ctive patient-rated satisfaction scores after treatment were significantly higher in the 4-point injection group than in the 3-point injection group (P = 0.028). The adverse events were pos

关键词： botulinum toxin type A crow's feet lines dose injection site

A discussion of fatigue properties of notched specimens subjected to prestressing treatment machined from FGH4097

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chinese Journal of Aeronautics 2024年第4期37卷 508-523页

作者： Rongxi SHI Dasheng WEI le HAN Shun YANG School of Energy and Power Engineering Beihang UniversityBeijing 100191China Jiangxi Research Institute Beihang UniversityNanchang 330096China Research Institute of Aero-Engine Beihang UniversityBeijing 100191China

Experimental and numerical investigations were performed to reveal the effect of prestress on the fatigue properties of FGH4097 so as to quantitatively evaluate the overspeed benefit of the disc of aeroengine. A corresponding experiment was performed to examine the effect of prestress on the fatigue life of FGH97. A complete model describing the fatigue properties of the prestressed notch specimen was proposed. After the modification of mean stress, stress gradient and prestressing treatment, the model is finally verified by fatigue test of presstressed notch specimens machined from FGH4097 with satisfactory accuracy and good engineering applicability. The new model highlights that for the variable fatigue loads, the introduction of appropriate prestress is expected to benefit to the notch specimens and certainly to the disc of aeroengine regards of their fatigue properties. Both the calculation method of fatigue life parameters and the prestress correction model are proved to have good prediction accuracy.

关键词： Turbine blisk Overspeed test Prestress Fatigue life prediction FGH4097

Re-entry rocket basic flow characteristics and thermal environment of different retro-propulsion modes

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chinese Journal of Aeronautics 2024年第7期37卷 190-203页

作者： Yifei SU Peijie SUN Yangwen cUI Guigao le School of mechanical Engineering Nanjing University of Science and TechnologyNanjing 210094China Shanghai Institute of Aerospace System Engineering Shanghai 200000China Southwest Institute of Technology and Engineering Chongqing 400039China

During the supersonic re-entry of multi-nozzle heavy rockets into the atmosphere,the basic flow state becomes increasingly complex due to the coupling effect between the retropropulsion plumes and the freestream.A numerical method using the hybrid Reynolds-Averaged Navier-Stokes and Large Eddy Simulation(RES)method and discrete coordinate method is developed to accurately estimate the thermal *** addition,finite rate chemical kinetics is used to calculate the afterburning *** numerical results agree well with wind tunnel data,which confirms the validity and accuracy of the numerical *** are conducted for the heavy carrier rocket re-entry from 53.1 km to 39.5 km altitude with 180°angle of attack by using three different Supersonic Retro-Propulsion(SRP)*** numerical results reveal that these three SRP flow fields are all Short Penetration models(SPm).As the re-entry altitudes decrease,both the plume-plume interaction and the plume-freestream interaction become *** highest temperatures in the plume shear layers of the three SRP modes increase by 8.36%,7.33%and 6.92%respectively after considering afterburning reactions,and all occur at a reentry altitude of 39.5 *** the rocket re-enters the atmosphere,the maximum heat flux on the rocket base plate of three SRP modes stabilizes at 290,170 and 200 kW/m^(2) respectively,but the maximum heat flux on the side wall increases *** the altitude declines to 39.5 km,the extreme heat flux of the three modes increase by 84.16%,49.45%and 62.97%respectively compared to that at 53.1 km.

关键词： Re-entry rocket multi-nozzle Supersonic retro propulsion Thermal environment Afterburning effect

Process intensification for the synthesis and purification of battery-grade Li_(2)cO_(3)with microfluidics

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Particuology 2024年第7期90卷 106-117页

作者： Haodu Li Jie Zhang Lin Dai le Du Jiqin Zhu The State Key Laboratory of chemical Resource Engineering College of Chemical EngineeringBeijing University of Chemical TechnologyBeijing 100029China

Battery-grade lithium carbonate(Li_(2)cO_(3))with a purity of higher than 99.5 wt%is of great importance as a high value-added lithium ***,influences of different reaction systems and process control on product purity remain ***,a membrane dispersion microreactor was used to enhance the mass transfer of preparation and purification processes in homogeneous and heterogeneous *** systems of Na_(2)cO_(3)–Licl,NH_(4)HcO_(3)–Licl,and NH_(3)·H_(2)O−cO_(2)−Licl,cO_(2)purification based on carbonation and decomposition were *** Li_(2)cO_(3)purity was increased by the improvement of mixing *** carbonation time was reduced by 62.5%and 58.3%for the NH_(3)·H_(2)O−cO_(2)and cO_(2)purification systems,*** the two ammonia-based systems,Li_(2)cO_(3)particles with a purity of 99.7–99.8 wt%were one-step prepared with a size of 3–5μm,which also met the requirement of the battery-grade *** purity was further increased to 99.9 wt%by cO_(2)purification and LiHcO_(3)*** investigation could provide a feasible alternative for the controllable preparation of battery-grade Li_(2)cO_(3)in one or multiple steps.

关键词： microfluidics Battery grade Li_(2)cO_(3) Process intensification High purity

Development of an ultrathin liquid sheet target for laser ion acc.leration at high repetition rates in the kilohertz range

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High Power Laser Science and Engineering 2024年第3期12卷 134-145页

作者： m.Füle A.P.Kovács T.Gilinger m.Karnok P.Gaál S.Figul G.marowsky K.Osvay National Laser-Initiated Transmutation Laboratory University of SzegedSzegedHungary Department of Experimental Physics University of SzegedSzegedHungary ELI ALPS ELI-HU Non-Profit Ltd.SzegedHungary Department of Optics and Quantum Electronics University of SzegedSzegedHungary Advanced microfluidic Systems GmbH GöttingenGermany

A colliding microjet liquid sheet target system was developed and tested for pairs of round nozzles of 10,11 and 18μm in *** sheet's position stability was found to be better than a few *** interaction with 50 mJ laser pulses,the 18μm jet has a resonance amplitude of 16μm at a repetition rate of 33 Hz,while towards 100 Hz it converges to 10μm for all nozzles.A white-light interferometric system was developed to measure the liquid sheet thickness in the target chamber both in air and in vacuum,with a measurement range of 182 nm±1μm and an accuracy of±3%.The overall shape and 3D shape of the sheet follow the Hasson±Peck model in *** vacuum versus air,the sheet gradually loses 10%of its thickness,so the thinnest sheet achieved was below 200 nm at a vacuum level of 10±4mbar,and remained stable for several hours of operation.

关键词： diagnostics laser ion acc.leration nanometric liquid sheet targets vacuum test

consumer transparency in the production chain for plant varieties produced using new genomic techniques

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aBIOTEcH 2024年第2期5卷 239-246页

作者： J.m.Lukasiewicz c.c.m.van de Wiel L.A.P.Lotz m.J.m.Smulders Wageningen University&Research P.O.Box 386NL-6700 AJ WageningenThe Netherlands

Plants edited with new genomic techniques(NGTs)currently fall under the Genetically modified Organisms Directive(2001/18/Ec)in the European *** the proposal of the European commission,NGT plants are partially exempted from the regulations of this *** proposal makes a distinction between two categories of NGT plants:NGT-1 and ***-1 category plants are considered equal to plants obtained through conventional breeding *** plants will not be labelled for the consumer,although they will be labelled as ***-2 category plants may be labelled with additional information as a positive *** of seeds of varieties made with gene editing,but not the products,would mean that most steps in the production chain are transparent,but not the last step towards ***“right to know”and increasing knowledge of gene-edited food is a common theme in food labelling towards ***,we describe current labelling regimes and registers and how these may be applied to provide transparency on gene-edited products to ***,we also look into consumer studies,which indicate a greater acceptance of gene-edited food among consumers,especially when additional benefits such as sustainability are mentioned.

关键词： Labelling New genomic techniques consumer transparency Plant products

mineralogical properties and co-sintering characteristics of fluxed iron ore with magnetite concentrates

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Journal of Iron and Steel Research International 2024年第2期31卷 318-328页

作者： le-le Niu Zheng-jian Liu Jian-liang Zhang Yao-zu Wang Zhen-xing Yang Si-da Li chang-dong Shan Ben Feng School of metallurgical and Ecological Engineering University of Science and Technology BeijingBeijing100083China Institute of Artificial Intelligence University of Science and Technology BeijingBeijing100083China Xinxing casting Pipe Xinjiang co. Bayingol841300XinjiangChina

To investigate the feasibility of co-sintering of fluxed iron ore with magnetite concentrates, the mineralogical properties of a novel fluxed iron ore were studied using particle size analysis, microscopic morphology characterization, and X-ray diffraction Rietveld analysis. Following that, the experiments for granulation performance and basic sintering characteristics were designed under seven different fluxed iron ore ratios, and the integrated ranking of different fluxed iron ore ratios was determined using gray relation analysis. Finally, the results of the industrial trails were combined with the feasibility analysis. Test and experimental results show that the fraction of the fluxed iron ore particles larger than 0.5 mm can account for more than 48%, and the particles have two morphologies: spherical-rough and flaky-smooth. ca elements are found in the form of calcite (cacO3) and dolomite (camg(cO3)2). The average particle size of granules and powder removal rate can be improved from 2.50 to 3.16 mm and 39.60% to 24.20%, respectively, with the increase in the fluxed iron ore ratio. Furthermore, the fluxed iron ore can improve assimilability and liquid fluidity of magnetite concentrates. In terms of overall granulation performance and sintering characteristics, the fluxed iron ore ratios are graded from best to worst as follows: 12%, 15%, 9%, 18%, 21%, 6% and 3%. The industrial trails show that when the fluxed iron ore ratio is increased, the beneficial effect of the superior sintering characteristics of the fluxed iron ore itself is ideally balanced with the negative effect of the lower amount of additional caO at 12% ratio, and thus, it is feasible to bring the fluxed iron ore into production at a level of roughly 12%.

关键词： Fluxed iron ore magnetite concentrate Granulation performance Sintering characteristics Gray relation analysis