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Effect of SiO_(2) Nanoparticles/Silicate on Characteristics of Micro-arc Oxidation Coating Formed on TC4 Alloy

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稀有金属材料与工程 2025年第1期54卷 76-83页

作者： Sun Fengyu Yang Zhao Hu jie Gong Yunbai Wang Ping Luo Qiming zhu Manlan School of New Energy and Materials Southwest Petroleum UniversityChengdu 610500China State Key Laboratory of Low-carbon Smart Coal-fired Power Generation and Ultra-clean Emission Nanjing 210046China

TC4 micro-arc oxidation(MAO)coatings were prepared by adding SiO_(2) nanoparticles or sodium silicate to the sodium meta-aluminate-based *** effect of additives was investigated by XRD,SEM,EDS,electrochemical and wear *** results show that additives can considerably accelerate the formation of MAO *** coatings are mostly composed of rutile and anatase TiO_(2),α-Al_(2)O_(3),γ-Al_(2)O_(3),Al_(2)TiO_(5) and SiO_(2).Sodium silicate and SiO_(2) nanoparticles added to the coating can effectively reduce the size of micropores and increase its thickness,whereas SiO_(2) nanoparticles with superior physical properties can be directly deposited at the discharge channel,significantly increasing the coating's resistance to wear and *** coating with SiO_(2) nanoparticles exhibits the best overall performance,with the lowest corrosion rate and average friction coefficient of 4.095×10^(-5)mm/a and 0.30,respectively.

关键词： micro-arc oxidation TC4 alloy coatings corrosion wea

Toxicity variability in Alexandrium pacificum isolated from East China Sea:impact of temperature and light intensity

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Journal of Oceanology and Limnology 2025年第1期43卷 147-158页

作者： Xuexia zhu Tianchi YIN Min PANG Jun WANG The First Institute of Oceanography Ministry of Natural Resources of the People’s Republic of ChinaQingdao 266061China College of Animal Science and Technology Yangzhou UniversityYangzhou 225009China College of Oceanography Hohai UniversityNanjing 210098China

Suitable temperature and light intensity play important roles in the formation of harmful algae blooms(HABs),which can pose serious threats to aquatic ecosystems and human *** this study,we measured the growth,physiological function,and paralytic shellfish toxins(PSTs)production of Alexandrium pacificum(CCMA-272),a strain isolated from East China Sea,at different temperatures(15,20,and 25℃)and light intensities(30,60,and 90μmol photons/(m^(2)·s)).Results indicate that temperature and light intensity significantly affected the growth,physiology,and toxigenic potentials of *** optimal conditions for the growth of *** were observed at 20℃ under60μmol photons/(m^(2)·s).Regarding the production of PSTs,this strain of *** produced 12 PSTs,including carbamate toxins:saxitoxin(STX),neosaxitoxin(NEO),and gonyautoxin 1–4(GTX1,GTX2,GTX3,GTX4);dicarbamoyl toxins:dicarbamoylsaxitoxin(dcSTX),dicarbamoylgonyautoxin 2,3(dcGTX2,dcGTX3);and N-sulfocarbamoyl toxins:N-sulfocarbamoylgonyautoxin 1,2(C1,C2),and gonyautoxin 5(GTX5).Among all the PSTs,C2 was the most *** temperature(15℃)and high light intensity(90μmol photons/(m^(2)·s))were beneficial for the production of PSTs in *** cultured at 20 and 25℃,*** generated comparable total quantities of PSTs,yet the toxicity levels were lower at 25℃.Intra-cellular PSTs contents were greater than extra-cellular PSTs contents,except those under the condition of 25℃ with 30μmol photons/(m^(2)·s).However,as the increase of temperature,*** released more amounts of analogues with higher toxicity levels(e.g.,STX and dcGTX_(2))into the environment than *** findings emphasize the significant sensitivity of *** to temperature and light intensity,highlighting the importance of evaluating both intra-cellular and extra-cellular PSTs for assessing its toxicity and aiding in the prediction and management of HABs.

关键词： temperature light intensity Alexandrium pacificum paralytic shellfish toxin harmful algal bloom

The potential of Ca isotopes to trace subducted marine carbonates in deep mantle

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Journal of Oceanology and Limnology 2025年第1期43卷 29-40页

作者： Hongli zhu Renqiang LIAO Long DU Zhaofeng ZHANG Key Laboratory of Ocean Observation and Forecasting Center of Deep Sea ResearchInstitute of OceanographyChinese Academy of SciencesQingdao 266071China Laboratory for Marine Geology Qingdao Marine Science and Technology CenterQingdao 266237China College of Earth Science and Engineering Shandong University of Science and TechnologyQingdao 266590China Research Center for Planetary Science College of Earth SciencesChengdu University of TechnologyChengdu 610059China

Marine carbonates,the major carrier of carbon upon the upper crust,can be subducted into the Earth’s interior along with oceanic crust,and then returned to the surface through magmatism,which constitute the deep carbon *** process plays an important role in modulating the CO_(2) concentrations in the atmosphere over geologic time,and thus the forming of the habitable ***,identifying recycled marine carbonates in the mantle is critical to well understand the global deep carbon *** is one of the major constituent cations in marine carbonates and its isotopes may be a potential tracer for recycled marine carbonates in the *** further evaluate the capability and challenges of Ca isotopes as such a geochemical tracer,we reviewed the Ca isotopic compositions in important reservoirs and the behavior of Ca isotopes during high-temperature geological processes that are related to the deep carbon cycle,including plate subduction,mantle metasomatism,mantle partial melting,magma differentiation,*** studies show that carbonate-rich marine sediments have significantly lowerδ^(44/40) Ca than the Earth mantle,and metasomatism by such recycled materials can cause lighter Ca isotopic compositions in deep mantle-derived rocks than those of the depleted mantle and mid ocean ridge ***,the Ca isotopic fractionation during partial melting of mantle peridotites is small(~0.10‰)and the Ca isotopic fractionation during plate subduction and intermediate-mafic magma evolution is *** investigations suggest that Ca isotopes have great advances in tracing such recycled materials in the ***,other processes(such as the influence by partial melts of eclogites)may induce similar effects on mantle-derived rocks as subducted marine carbonates but still remains debated,and thus further investigations are strongly needed in the future.

关键词： Ca isotope marine carbonate mantle metasomatism partial melting fractional crystallization

Sequence-activated chemiluminescence probes:programmable illumination for high-contrast in vivo sensing and imaging

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Science China Chemistry 2025年第1期68卷 26-34页

作者： Yutao Zhang Juan Li Wei-Hong zhu Zhiqian Guo Shanghai Key Laboratory of Functional Materials Chemistry Joint International Research Laboratory of Precision Chemistry and Molecular EngineeringInstitute of Fine ChemicalsSchool of Chemistry and Molecular EngineeringEast China University of Science and TechnologyShanghai 200237China State Key Laboratory of Bioreactor Engineering Shanghai Frontier Science Research Base of Optogenetic Techniques for Cell MetabolismEast China University of Science&TechnologyShanghai 200237China

Sequence-activated chemiluminescence(CL)technique offers a unique approach to detecting specific biomolecules or cellular events with high sensitivity and spatial *** fundamental principle behind sequence-activated CL probes involves tailoring highly-controllable CL signals in response to specific sequences or events of interest,thus enabling high-contrast signals under complex physiological *** sequential activation could be triggered by enzymes,reactive oxygen species(ROS),biothiols or changes in the *** unique sequence-activated CL probes bestow several advantages,including minimal background,deep-tissue penetration,and the ability of non-invasive or minimally invasive *** sequence-activated CL techniques represent a significant advancement in molecular imaging and *** this mini-review,we focus on the latest developments in sequential CL probes,addressing the technical challenges and discussing the future trajectory by harnessing CL signaling and molecular recognition.

关键词： chemiluminescnece sequence-activation in-vivo bioimaging cyclic peroxide

Synergistic BrΦnsted/Lewis acid catalyzed atroposelective synthesis of aryl-β-naphthol

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Chinese Chemical Letters 2025年第1期36卷 293-298页

作者： Jiajun Lu Zhehui Liao Tongxiang Cao Shifa zhu Key Laboratory of Functional Molecular Engineering of Guang-dong Province School of Chemistry and Chemical EngineeringSouth China University of TechnologyGuangzhou 510640China School of Chemistry and Chemical Engineering Zhejiang Sci-Tech UniversityHangzhou 310018China State Key Laboratory of Elemento-Organic Chemistry Nankai UniversityTianjin 300071China

Axially chiral binaphthol have achieved great success in asymmetric *** toα-binaphthol,axially chiral aryl-β-naphthol are far less ***,we report a method of asymmetric catalysis to constructβ-naphthol with up to 99%yield,95.5:4.5 enantiomeric ratio,using alkynyl esters as precursors and chiral phosphonic acid(CPA)/Lewis acid as *** steps involve oxygen transfer and de novo arene formation to set up the chiral ***,this methodology provides a versatile platform for structurally divergent synthesis of atroposelectiveβ-naphthol analogs,which are widely found in bioactive molecules and asymmetric catalysts.

关键词： Synergistic catalysis Atropisomerism Aryl-β-naphthol Enantioselectivity Tandem reaction

Spatio-temporal patterns and climatic drivers of spring phenology in eight forest communities across the north-south transitional zone of China

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Journal of Geographical Sciences 2025年第1期35卷 17-38页

作者： zhu Wenbin LU Yu Institute of Geographic Sciences and Natural Resources Research CASBeijing100101China School of Geographical Science Nanjing University of Information Science&TechnologyNanjing210044China

The Qinba Mountains are climatically and ecologically recognized as the north-south transitional zone of *** of its phenology is critical for comprehending the response of vegetation to climatic *** retrieved the start of spring phenology(SOS)of eight forest communities from the MODIS products and adopted it as an indicator for spring *** analysis,partial correlation analysis,and GeoDetector were employed to reveal the spatio-temporal patterns and climatic drivers of *** results indicated that the SOS presented an advance trend from 2001 to 2020,with a mean rate of−0.473 d yr^(−1).The SOS of most forests correlated negatively with air temperature(TEMP)and positively with precipitation(PRE),suggesting that rising TEMP and increasing PRE in spring would forward and delay SOS,*** dominant factors influencing the sensitivity of SOS to climatic variables were altitude,forest type,and latitude,while the effects of slope and aspect were relatively *** response of SOS to climatic factors varied significantly in space and among forest communities,partly due to the influence of altitude,slope,and aspect.

关键词： spring phenology climatic drivers altitude forest communities lag effect Qinba Mountains

Dynamic generation of multiplexed vortex beams by a space-time-coding metasurface

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Photonics Research 2025年第1期13卷 225-234页

作者： PENGCHENG TANG LIMING SI QIANQIAN YUAN jie TIAN JIAXUAN DENG TIANYU MA XIUE BAO CHONG HE WEIREN zhu Beijing Key Laboratory of Millimeter Wave and Terahertz Technology School of Integrated Circuits and ElectronicsBeijing Institute of Technology Department of Electronic Engineering Shanghai Jiao Tong University

Dynamic generation of multimode vortex waves carrying orbital angular momentum (OAM) utilizing programmable metasurfaces has attracted considerable attention. Yet, it is still a challenge to achieve multiplexed vortex waves with an arbitrary customized mode combination, stemming fundamentally from the discrete control over phase exhibited by current programmable metasurfaces, which are typically constrained to a limited 1-bit or 2-bit discrete resolution.

关键词： Field programmable gate arrays Indium tin oxide Millimeter waves Phase modulation Space division multiplexing Spiral phase

Defect Engineering with Rational Dopants Modulation for High‑Temperature Energy Harvesting in Lead‑Free Piezoceramics

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Nano-Micro Letters 2025年第3期17卷 87-101页

作者： Kaibiao Xi Jianzhe Guo Mupeng Zheng Mankang zhu Yudong Hou Key Laboratory of Advanced Functional Materials Ministry of EducationCollege of Materials Science and EngineeringBeijing University of TechnologyBeijing 100124People’s Republic of China

High temperature piezoelectric energy harvester(HTPEH)is an important solution to replace chemical battery to achieve independent power supply of HT wireless ***,simultaneously excellent performances,including high figure of merit(FOM),insulation resistivity(ρ)and depolarization temperature(Td)are indispensable but hard to achieve in lead-free piezoceramics,especially operating at 250°C has not been reported ***,well-balanced performances are achieved in BiFeO3–BaTiO3 ceramics via innovative defect engineering with respect to delicate manganese *** to the synergistic effect of enhancing electrostrictive coefficient by polarization configuration optimization,regulating iron ion oxidation state by high valence manganese ion and stabilizing domain orientation by defect dipole,comprehensive excellent electrical performances(Td=340°C,ρ250°C>10^(7)Ωcm and FOM_(250°C)=4905×10^(–15)m^(2)N^(−1))are realized at the solid solubility limit of manganese *** HT-PEHs assembled using the rationally designed piezoceramic can allow for fast charging of commercial electrolytic capacitor at 250°C with high energy conversion efficiency(η=11.43%).These characteristics demonstrate that defect engineering tailored BF-BT can satisfy high-end HT-PEHs requirements,paving a new way in developing selfpowered wireless sensors working in HT environments.

关键词： Lead-free piezoceramic Defect engineering Dopants modulation High-temperature Piezoelectric energy harvester

Effect of pyrite content on chalcopyrite flotation under different regrinding conditions

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International Journal of Minerals,Metallurgy and Materials 2025年第1期32卷 49-57页

作者： Zejun Wang Qing Shi Guofan Zhang Yuxuan zhu Binbin Li School of Minerals Processing and Bioengineering Central South UniversityChangsha 410083China Key Laboratory of Hunan Province for Clean and Efficient Utilization of Strategic Calcium-containing Mineral Resources Central South UniversityChangsha 410083China

This study aimed to investigate the effect of varying pyrite(Py)content on copper(Cu)in the presence of different regrinding conditions,which were altered using different types of grinding media:iron,ceramic balls,and their mixture,followed by flotation in the cleaner *** flotation performance of rough Cu concentrate can be improved by changing the regrinding conditions based on the Py *** electron microscopy,X-ray spectrometry,ethylenediaminetetraacetic acid disodium salt extraction,and X-ray photoelectron spectroscopy studies illustrated that when the Py content was high,the use of iron media in regrinding promoted the generation of hydrophilic Fe OOH on the surface of Py and improved the Cu *** ceramic medium with a low Py content prevented excessive Fe OOH from covering the surface of chalcopyrite(Cpy).Electrochemical studies further showed that the galvanic corrosion current of Cpy-Py increased with the addition of Py and became stronger with the participation of iron media.

关键词： chalcopyrite regrinding media pyrite galvanic corrosion flotation