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Artificial intelligence-aided semi-automatic joint trace detection from textured three-dimensional models of rock mass
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作者 Seyedahmad Mehrishal Jineon Kim +1 位作者 Yulong Shao Jae Joon Song 《Journal of Rock Mechanics and Geotechnical Engineering》 2025年第4期1973-1985,共13页
It is of great importance to obtain precise trace data,as traces are frequently the sole visible and measurable parameter in most outcrops.The manual recognition and detection of traces on high-resolution three-dimens... It is of great importance to obtain precise trace data,as traces are frequently the sole visible and measurable parameter in most outcrops.The manual recognition and detection of traces on high-resolution three-dimensional(3D)models are relatively straightforward but time-consuming.One potential solution to enhance this process is to use machine learning algorithms to detect the 3D traces.In this study,a unique pixel-wise texture mapper algorithm generates a dense point cloud representation of an outcrop with the precise resolution of the original textured 3D model.A virtual digital image rendering was then employed to capture virtual images of selected regions.This technique helps to overcome limitations caused by the surface morphology of the rock mass,such as restricted access,lighting conditions,and shading effects.After AI-powered trace detection on two-dimensional(2D)images,a 3D data structuring technique was applied to the selected trace pixels.In the 3D data structuring,the trace data were structured through 2D thinning,3D reprojection,clustering,segmentation,and segment linking.Finally,the linked segments were exported as 3D polylines,with each polyline in the output corresponding to a trace.The efficacy of the proposed method was assessed using a 3D model of a real-world case study,which was used to compare the results of artificial intelligence(AI)-aided and human intelligence trace detection.Rosette diagrams,which visualize the distribution of trace orientations,confirmed the high similarity between the automatically and manually generated trace maps.In conclusion,the proposed semi-automatic method was easy to use,fast,and accurate in detecting the dominant jointing system of the rock mass. 展开更多
关键词 Automatic trace detection Digital joint mapping Rock discontinuities characterization Three-dimensional(3D)trace network
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Quantitative detection of trace nanoplastics (down to 50 nm) via surface-enhanced Raman scattering based on the multiplex-feature coffee ring 被引量:1
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作者 Xinao Lin Fengcai Lei +5 位作者 Xiu Liang Yang Jiao Xiaofei Zhao Zhen Li Chao Zhang Jing Yu 《Opto-Electronic Advances》 2025年第6期27-39,共13页
Quantitative detection of trace small-sized nanoplastics(<100 nm)remains a significant challenge in surface-enhanced Raman scattering(SERS).To tackle this issue,we developed a hydrophobic CuO@Ag nanowire substrate ... Quantitative detection of trace small-sized nanoplastics(<100 nm)remains a significant challenge in surface-enhanced Raman scattering(SERS).To tackle this issue,we developed a hydrophobic CuO@Ag nanowire substrate and introduced a multiplex-feature analysis strategy based on the coffee ring effect.This substrate not only offers high Raman enhancement but also exhibits a high probability of detection(POD),enabling rapid and accurate identification of 50 nm polystyrene nanoplastics over a broad concentration range(1–10−10 wt%).Importantly,experimental results reveal a strong correlation between the coffee ring formation and the concentration of nanoplastic dispersion.By incorporating Raman signal intensity,coffee ring diameter,and POD as combined features,we established a machine learning-based mapping between nanoplastic concentration and coffee ring characteristics,allowing precise predictions of dispersion concentration.The mean squared error of these predictions is remarkably low,ranging from 0.21 to 0.54,representing a 19 fold improvement in accuracy compared to traditional linear regression-based methods.This strategy effectively integrates SERS with wettability modification techniques,ensuring high sensitivity and fingerprinting capabilities,while addressing the limitations of Raman signal intensity in accurately reflecting concentration changes at ultra-low levels,providing a new idea for precise SERS measurements of nanoplastics. 展开更多
关键词 quantitative detection of trace nanoplastics surface-enhanced Raman scattering coffee ring multiplexfeature analysis machine learning
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Research on biochar prepared by trace KOH catalyzed CO_(2) activation vs KOH activation as advanced candidate for carbon capture
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作者 DENG Lihua XIA Wei +4 位作者 YANG Zhikun ZHANG Wenda FENG Dongdong SUN Shaozeng ZHAO Yijun 《燃料化学学报(中英文)》 北大核心 2025年第9期1330-1341,I0001-I0014,共26页
The technology for green and macro-conversion of solid waste biomass to prepare high-quality activated carbon demands urgent development.This study proposes a technique for synthesizing carbon adsorbents using trace K... The technology for green and macro-conversion of solid waste biomass to prepare high-quality activated carbon demands urgent development.This study proposes a technique for synthesizing carbon adsorbents using trace KOH-catalyzed CO_(2) activation.Comprehensive investigations were conducted on three aspects:physicochemical structure evolution of biochar,mechanistic understanding of trace KOH-facilitated CO_(2) activation processes,and application characteristics for CO_(2) adsorption.Results demonstrate that biochar activated by trace KOH(<10%)and CO_(2) achieves comparable specific surface area(1244.09 m^(2)/g)to that obtained with 100%KOH activation(1425.10 m^(2)/g).The pore structure characteristics(specific surface area and pore volume)are governed by CO and CH4 generated through K-salt catalyzed reactions between CO_(2) and biochar.The optimal CO_(2) adsorption capacities of KBC adsorbent reached 4.70 mmol/g(0℃)and 7.25 mmol/g(25℃),representing the maximum values among comparable carbon adsorbents.The 5%KBC-CO_(2) sample exhibited CO_(2) adsorption capacities of 3.19 and 5.01 mmol/g under respective conditions,attaining current average performance levels.Notably,CO_(2)/N_(2) selectivity(85∶15,volume ratio)reached 64.71 at 0.02 bar with robust cycling stability.Molecular dynamics simulations revealed that oxygen-containing functional groups accelerate CO_(2) adsorption kinetics and enhance micropore storage capacity.This technical route offers simplicity,environmental compatibility,and scalability,providing critical references for large-scale preparation of high-quality carbon materials. 展开更多
关键词 BIOCHAR trace KOH catalyzed activation CO_(2)activation carbon capture
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Trace Element Concentrations in the Sera of Pregnant Women in Kisangani, Democratic Republic of Congo
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作者 Likilo Osundja Jérémie Komanda Likwekwe Emmanuel +3 位作者 Tshodi Bulanda Arsène Juakali Sihalikyolo Jean-Jeannot Buhendwa Mirindi Victor Katenga Bosunga Gédéon 《Journal of Biosciences and Medicines》 2025年第2期218-229,共12页
Introduction: During pregnancy, the increased demand for all the nutrients required for the development of the foetus means that the maternal stock of trace elements and minerals may become unbalanced if dietary intak... Introduction: During pregnancy, the increased demand for all the nutrients required for the development of the foetus means that the maternal stock of trace elements and minerals may become unbalanced if dietary intake fails to compensate. The aim of this research is to determine the status of trace elements (calcium, copper, magnesium, selenium and zinc) in pregnant women in the city of Kisangani. Methods: We carried out an analytical cross-sectional study of non-pregnant and pregnant women living in Kisangani, from 05 October 2023 to 05 January 2024. Concentrations of trace elements in sera were analysed using an inductively coupled plasma mass spectrophotometer (ICP-MS Agilent 7700X). Statistical analysis of the data was performed using R software version 4.3.0. Results: The mean age was 26.3 ± 6.7 years;the mean copper and magnesium levels in the serum of pregnant women were 12.58 ± 1.13 micromol/l and 1.03 ± 1.03 mmol/l respectively. The medians for calcium and zinc were 1.49 mmol/l and 8.42 micromol/l. The selenium mode was 0.41 micromol/l. Variations in trace element levels in sera of pregnant women were 0.94 - 2.22 mmol/l for calcium;0.31 - 0.78 micromol/l for selenium;and 7.29 - 12.72 micromol/l for zinc;11.04 - 14.99 micromol/l for copper, and 0.082 - 1.05 mmol/l for magnesium. Conclusion: Serum trace element concentrations in pregnant women were lower than those observed in non-pregnant women. Trace element reserves in pregnant women depended on their nutrient status prior to pregnancy, hence, there was an urgent need for trace element balance prior to pregnancy. 展开更多
关键词 trace Element Zinc Copper SELENIUM CALCIUM Magnesium Pregnant Woman SERUM Kisangani
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Determination of Organic Matter and Trace Metals Elements (As, Sb, Cd, Hg, Ni, Pb, Cr, Zn) in the Soils of the Banks of Watercourses in Brazzaville City (Republic of Congo)
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作者 Mbianda Nfong-Ya Orline Lesley Nzila Jean de Dieu +5 位作者 Louzayadio Mvouezolo Raison Félicien Bonazaba Milandou Longin Justin Clair Nguelet-Moukaha Isidore Wando Georgy Patience Ouamba Jean Maurille Aina Martin Pépin 《Open Journal of Soil Science》 2025年第2期156-172,共17页
This work focused on determining the physico-chemical characteristics (pH, carbon and nitrogen) and trace metal elements (TMEs) content (As, Sb, Cd, Hg, Ni, Pb, Cr, Zn) of soils in the Brazzaville city. Soil samples w... This work focused on determining the physico-chemical characteristics (pH, carbon and nitrogen) and trace metal elements (TMEs) content (As, Sb, Cd, Hg, Ni, Pb, Cr, Zn) of soils in the Brazzaville city. Soil samples were taken from a depth of 0 to 20 cm using a hand auger on both banks of five tributaries of the Congo River (Djoué, Mfilou, Mfoa, Tsiémé, Djiri) that flow through the city of Brazzaville. 90 sampling points were defined, with 3 points 250 m apart on the banks and located, for each river, at three sites: upstream, midstream and downstream. Finally, 15 composite samples representative of the study area were taken. The average pH values of the water varied between 6.5 and 7.5. These pH values show that the soils studied are neutral. Total carbon content varied between 0.7% (Djiri) and 1.6% (Djoué). Total nitrogen content ranged from 0.08% (Djiri) to 0.12% (Djoué). TMEs contents varied from 0.5 to 1.8 mg/kg for Sb, from 0.5 to 2.5 mg/kg for As, from 0.1 to 0.18 mg/kg for Cd, from 4.2 to 11.3 mg/kg for Cr, from 0.07 to 0.27 mg/kg for Hg, from 0.7 to 2.4 mg/kg for Ni, from 0 to 158 mg/kg for Pb and from 16 to 105 mg/kg for Zn. The lowest TMEs levels were observed in the soils of the Djiri river, while the highest levels were observed in the soils of the Djoué and Tsiémé rivers. The ANOVA and Bonferroni test did not show significant differences in the means of the parameters measured (p > 0.05). The TMEs levels were below the accepted standards (NF U44-041), with the exception of Pb, which had high levels downstream of the Djoué. According to the pollution index values calculated using soil TME content, the soils on the banks of the Djoué river are considered polluted, while those on the banks of the Tsiémé river are moderately polluted, those on the banks of the Mfoa and Mfilou rivers are slightly polluted, and the soils on the banks of Djiri river are unpolluted. 展开更多
关键词 Carbon Nitrogen trace Metal Elements Soil BRAZZAVILLE CONGO
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Major-and Trace-Element Chemistry of Clinopyroxene and Amphibole from High-Mg Diorite in Chelyabinsk Massif(Urals):Insights into Petrogenesis and Magma Source Constraints
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作者 Tatiana Osipova Gennadiy Kallistov +1 位作者 Maria Chervyakovskaya Vasiliy Chervyakovskiy 《Journal of Earth Science》 2025年第2期508-523,共16页
Field-and petrographic investigations,together with microanalytical major-and traceelement studies,were carried out on clinopyroxene and amphibole from high-Mg diorite in the subduction-related Chelyabinsk granitic ma... Field-and petrographic investigations,together with microanalytical major-and traceelement studies,were carried out on clinopyroxene and amphibole from high-Mg diorite in the subduction-related Chelyabinsk granitic massif to understand its petrogenesis and source.The clinopyroxene composition(high Mg#,Cr-content,sum of REE and Ti/Eu ratio;depletion in HREE;negative Eu-anomaly)indicates that it formed from a reduced melt derived from a mantle source metasomatized by fluids/melts having crustal affinity.Melt compositions in equilibrium with clinopyroxene and amphibole were calculated using solid/liquid partition coefficients.The high Nb/Y and Zr/Y ratio values of a liquid simulated from clinopyroxene,which appears to have very similar characteristics to sanukitoid melts,indicate a low degree of melting of the mantle source.Melt simulated from amphibole is more evolved and more felsic(dacitic).It displays a geochemical“amphibole fractionation”signature,indicating the peritectic transformation of clinopyroxene to amphibole in the lower crust.Rock textures and major element mineral compositions suggest that further amphibole was precipitated directly from the melt in the middle crust.The results show that the Chelyabinsk highMg diorite was probably formed as a cumulate from sanukitoid-like melt during its ascent and cooling below dacitic liquidus inside the amphibole stability field. 展开更多
关键词 high-Mg diorite CLINOPYROXENE amphibole trace elements cumulus mineral SANUKITOID URALS geochemistry
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Magmatic to Hydrothermal Evolution of Bianjiadayuan Ag-Pb-Zn-Sn Deposit,Northeast China:A Quartz Texture and Trace Elements Study
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作者 Xin Wang Nan Qi +3 位作者 Xinyou Zhu Xi-Heng He Haowei Gu Xiaohua Deng 《Journal of Earth Science》 2025年第4期1493-1504,共12页
Quartz trace elements are extensively employed in studying magmatic evolution,fluid evolution,and metal enrichment.The Bianjiadayuan Ag-Pb-Zn-Sn deposit is a typical magmatichydrothermal system in northeastern China,h... Quartz trace elements are extensively employed in studying magmatic evolution,fluid evolution,and metal enrichment.The Bianjiadayuan Ag-Pb-Zn-Sn deposit is a typical magmatichydrothermal system in northeastern China,however,studies on its complex magmatic-hydrothermal evolution are limited.This study investigates the quartz from the Bianjiadayuan deposit to gain insight into the physicochemical evolution of mineralization using cathodoluminescence(CL)textures and laser ablation-inductively coupled plasma-mass spectrometry(LA-ICP-MS)of quartz.Five types quartz(Q1 to Q5)were identified.From Q1 in quartz porphyry to Q5 in Ag-Pb-Zn veins,the CL intensity and Ti content gradually decreases,and Ge,Ge/Ti,and Al/Ti ratios increase,indicating a temperature decline from magmatic to hydrothermal stages.The Sb content shows an opposite trend to Ti content,correlating positively with Ge content in quartz,suggesting that Sb content could also be temperature-dependent.These trace elements in quartz indicate cooling is critical for Ag mineralization.Furthermore,quartz phenocryst(Q1)from the quartz porphyry shows low Al/Ti(mostly<4)and Ge/Ti ratios(<0.04),suggesting a low degree of magmatic evolution.The Sb content in Q5 from Ag-Pb-Zn-quartz veins(>1 ppm,mostly tens of ppm)is notably higher compared to quartz in other lithologies including Sn-bearing quartz veins(<1 ppm),suggesting that Sb contents can serve as an effective indicator of Ag mineralization. 展开更多
关键词 QUARTZ trace elements Ag mineralization Ag-Pb-Zn-Sn deposit Bianjiadayuan
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Environmental Pollution History at the Oujiang Estuary Since 5800 Years:Evidence from Trace Metal Elements
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作者 WANG Shengyu LIU Jinqing +4 位作者 SONG Hongying FENG Xiaokun YIN Ping DUAN Xiaoyong CAO Ke 《Journal of Ocean University of China》 2025年第5期1289-1300,I0002,共13页
We investigated the concentrations,vertical distribution,and enrichment status of ten trace metal elements(Cr,Hg,Cu,Pb,Zn,Cd,As,Co,V,and Ni)in sediments of core D04 from the muddy area outside the Oujiang River Estuar... We investigated the concentrations,vertical distribution,and enrichment status of ten trace metal elements(Cr,Hg,Cu,Pb,Zn,Cd,As,Co,V,and Ni)in sediments of core D04 from the muddy area outside the Oujiang River Estuary.In addition to V,As,and Hg,the concentrations of Cr,Cu,Zn,Pb,Cd,Ni and Co were constrained by sediment grain size and organic matter.Al-though the concentrations of trace metals fluctuated during the 5.8–2.5 kyr BP period,overall variations remained relatively stable.However,during the 2.5–0 kyr BP period,the concentrations of Cd,Zn,Cu,Pb,Ni,Ni,and Cr showed an increasing trend within the fluctuations,ultimately reaching relatively high levels.The muddy area was lightly contaminated by heavy metals such as As,Hg,and Cu.The concentrations of Hg,As,and Cu have been continuously increasing since 2.5 kyr BP,indicating clear impacts from fre-quent human activities. 展开更多
关键词 trace metals historic variation enrichment trends muddy area Oujiang River Estuary
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Trace analysis of 59 halogenated aromatic disinfection byproducts through the SPE-LC-MS/MS method and their occurrence and transformation during chlorine disinfection
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作者 Shuang Chen Yue Qiao +5 位作者 Youwei Jiang Wei Qiu Shuang Zang Jing Zhang Xianshi Wang Jun Ma 《Journal of Environmental Sciences》 2025年第11期821-832,共12页
Halogenated aromatic disinfection byproducts(DBPs)are gradually receiving attention due to their high detection frequency and usually higher toxicity than regulated DBPs.In this study,we established a solid phase extr... Halogenated aromatic disinfection byproducts(DBPs)are gradually receiving attention due to their high detection frequency and usually higher toxicity than regulated DBPs.In this study,we established a solid phase extraction(SPE)-LC-MS/MS method to simultaneously trace analyze 59 halogenated aromatic DBPs.The limits of detection and limits of quantification of halogenated aromatic DBPs ranged from 0.03 to 135.23 ng/L and from 0.1 to 450.76 ng/L,respectively.The range of recoveries and relative standard deviation(RSD)in river water were between 72.41%to 119.54%and 1.86%to 16.03%,respectively.Therefore,this method can be used to accurately analyze trace levels of halogenated aromatic DBPs in drinking water.The occurrence and transformation of halogenated aromatic DBPs were explored based on this method.In the chlorinated simulated source water and chlorinated river water,20 and 45 halogenated aromatic DBPs were determined,respectively.The active halogen species(HOCl,HOBr,and HOI)first reacted with natural organic matter(NOM)to form halogenated aromatic DBPs.Then,chlorine further reacted with the halogenated aromatic DBPs to convert them into small-molecule halogenated aliphatic DBPs through oxidation,electrophilic substitution,and hydrolysis reaction,etc.In the chlorinated simulated source water,chlorinated river water,and tap water,the toxicity contribution of bromoacetic acids(Br-HAAs)accounted for themajority(>71.16%).Given that halogenated aromatic DBPs are intermediate products of halogenated aliphatic DBPs,controlling the formation of halogenated aromatic DBPs is beneficial in decreasing the formation of halogenated aliphatic DBPs,thereby diminishing the toxicity of drinking water. 展开更多
关键词 Halogenated aromatic disinfection byproducts trace analysis CHLORINE Drinking water Calculated toxicity
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Assessment of trace elements distribution and sources from snowpits in the Lambert Glacier region,coastal East Antarctica
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作者 Yalalt Nyamgerel Soon Do Hur +3 位作者 Tseren-Ochir Soyol-Erdene Cunde Xiao Hyejung Jung Jeonghoon Lee 《Geoscience Frontiers》 2025年第3期425-437,共13页
The measurement of trace elements in Antarctic snow is crucial for understanding historical atmospheric geochemical changes and circulation patterns.However,studies on their spatial distributions remain limited,partic... The measurement of trace elements in Antarctic snow is crucial for understanding historical atmospheric geochemical changes and circulation patterns.However,studies on their spatial distributions remain limited,particularly those evaluating multiple metals across several snowpits,making interpretation challenging.This study investigates the distributions and sources of trace elements-including Cd,Ba,Pb,U,Bi,V,Mn,Fe,Cu,Zn,and As-across four snowpits in the Lambert Glacier Basin,East Antarctica.The trace elements exhibit site-,element-,and season-dependent variations,with higher concentrations observed at inland sites.In contrast,δ^(18)O and ion concentrations decrease with increasing distance from the coast and elevation,underscoring the influence of marine emissions.Crustal sources primarily contributed to Ba,U,V,Mn,and Fe,while non-crustal sources predominantly contributed to Cd,Bi,Zn,Pb,Cu,and As.Positive matrix factorization(PMF)analysis indicates that trace element concentrations in Pits 2 and 3 are influenced by both crustal and non-crustal sources,while Pit 4 reflects a mixed-source influence.Pit 1(coastal site)also indicates the mixed sources with influence of a highly dynamic marine climate and environment.The PMF results reveal similarities in emission sources and atmospheric transport patterns across the snowpits,facilitating a more comprehensive interpretation of longer ice core records.Overall,this study provides valuable insights into trace element distributions and enhances our understanding of past environmental and climatic conditions. 展开更多
关键词 trace elements Spatial variation ANTARCTICA Lambert Glacier Basin Positive matrix factorization
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The key role of Zn in enhancing precipitation kinetics and refinement of Mg_(17)Al_(12)and Mg_(2)Sn phases through trace Na additions
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作者 Sumi Jo Tae-Hoon Kim +1 位作者 Cheol-Woong Yang Young Min Kim 《Journal of Magnesium and Alloys》 2025年第6期2740-2751,共12页
This study investigates zinc’s(Zn)key role in enhancing the precipitation kinetics and refinement of Mg_(17)Al_(12)and Mg_(2)Sn phases in magnesium alloys through trace sodium(Na)additions.Magnesium alloys with varyi... This study investigates zinc’s(Zn)key role in enhancing the precipitation kinetics and refinement of Mg_(17)Al_(12)and Mg_(2)Sn phases in magnesium alloys through trace sodium(Na)additions.Magnesium alloys with varying compositions of aluminum(Al),tin(Sn),Zn,and Na were prepared and aged at 453 K.Microstructural analyses were conducted using transmission electron microscopy(TEM),scanning transmission electron microscopy(STEM),and atom probe tomography(APT).Trace additions of Na significantly enhanced the precipitation responses of both Mg_(17)Al_(12)and Mg_(2)Sn phases.When Zn was co-added with Na,as in the ATZ641N3 alloy(Mg–6Al–4Sn–1Zn–0.3Na),there was a pronounced refinement in precipitate morphology and acceleration of precipitation kinetics.The ATZ641N3 alloy achieved a peak hardness of 103 Hv at 36 hours,compared to 91 Hv at 72 hours for the ATZ641 alloy without Na.The simultaneous addition of Zn and Na led to the formation of Sn–Na–Zn particles that acted as effective nucleation sites for Mg_(2)Sn,promoting aluminum partitioning and accelerating the precipitation of Mg_(17)Al_(12)through Al-rich regions.Additionally,Zn and Na co-segregated within the Mg_(17)Al_(12)phase,reducing misfit strain caused by Zn substitution and improving precipitate stability and refinement.These findings highlight Zn’s critical role,alongside trace Na additions,in refining and accelerating the precipitation of Mg_(17)Al_(12)and Mg_(2)Sn phases,thereby enhancing the age-hardening response of magnesium alloys. 展开更多
关键词 Magnesium alloys Precipitation hardening trace elements Na and Zn interaction Microstructural refinement
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Trace sulfurization engineering enabling improved initial coulombic efficiency and high reversible sodium-ion storage in bismuth-based anode
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作者 Ruijie Chen Xiaoling Qiu +5 位作者 Keren Luo Zhiqiang Zhong Xiaoran Wang Yuchen Fu Wenlong Cai Hao Wu 《Journal of Energy Chemistry》 2025年第4期79-89,共11页
Bismuth(Bi)anodes have been widely investigated for potential application in sodium-ion batteries(SIBs)due to their ultrahigh theoretical volumetric capacity(3800 mAh cm^(-3))and suitable sodiation potential(0.5-0.7 V... Bismuth(Bi)anodes have been widely investigated for potential application in sodium-ion batteries(SIBs)due to their ultrahigh theoretical volumetric capacity(3800 mAh cm^(-3))and suitable sodiation potential(0.5-0.7 V).Unfortunately,either Bi or Bi-based compounds still face tricky challenges of unsatisfying reversible capacity(<350 mAh g^(-1))and inferior initial Coulombic efficiency(ICE,<70%).Herein,a controllable trace-sulfurization strategy is proposed to address these challenges by developing a yolkshell Bi/Bi_(2)S_(3)heterostructure encapsulated within S-doped carbon shells(TS-Bi/C).This approach strategically incorporates a trace amount of high-capacity Bi_(2)S_(3)phase with metallic Bi,consequently building regional Bi/Bi_(2)S_(3)heterointerfaces for enhancing interfacial charge transfer and sodium storage reversibility.Moreover,a thin and homogeneous solid electrolyte film(~5 nm)was formed on the surface of TS-Bi/C during the initial discharge-charge process.These merits result in an approximate 30%increase in ICE of TS-Bi/C(87.4%)compared to pure Bi/C(57,6%)when employed as anodes in SIBs,together with boosted discharge capacity of 462.3 mAh g^(-1)at 0.1 A g^(-1)and high rate capability of 382.4 mAh g^(-1)at 10 A g^(-1).Importantly,as compared to both Bi/C and Bi_(2)S_(3)/C counterparts,TS-Bi/C can deliver superior volumetric capacity as high as 1553 mAh cm^(-3)owing to its considerable tap density of 3.43 g cm^(-3). 展开更多
关键词 Sodium ion batteries Bi-based anode Bismuth sulfide trace sulfurization HETEROSTRUCTURE S-doped carbon shell SEI film
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Effects of combined preconception and prenatal myo-inositol, probiotics, and trace element supplementation on the outcomes of depressed mothers
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作者 Shu-Fang Qi Hong-Xia Sun Jie Zhao 《World Journal of Psychiatry》 2025年第7期91-102,共12页
BACKGROUND Perinatal depression affects 10%-20%of pregnant women and subsequently influences maternal health and fetal development.Concerns over the safety of antidepressants during pregnancy have prompted the explora... BACKGROUND Perinatal depression affects 10%-20%of pregnant women and subsequently influences maternal health and fetal development.Concerns over the safety of antidepressants during pregnancy have prompted the exploration of nutritional interventions as adjunct therapies.This study evaluated the impact of combining preconception and prenatal supplementation with myo-inositol,probiotics,and trace elements on mood,quality of life,and fetal development in depressed mothers.This retrospective cohort study included 314 pregnant women who were diag-nosed with mild to moderate depression,as determined by a Zung self-rating depression scale score of less than 69.The participants were divided into an intervention group(n=161)receiving myo-inositol,probiotics,and trace elements and a control group(n=153)without supplementation.Supplementation comm-enced 3 months before conception and continued through pregnancy.Psychiatric symptoms and quality of life were evaluated using the positive and negative affect schedule-now,state-trait anxiety inventory,Patient Health Ques-tionnaire-8,and World Health Organization Quality of life Assessment:Brief Version scales preconception and postpartum.Fetal development metrics were assessed via ultrasound,and neonatal outcomes were recorded.RESULTS The intervention group presented significant reductions in gestational diabetes mellitus(13.04%vs 23.53%,P=0.016)and gestational hypertension(3.73%vs 9.15%,P=0.049).Higher levels of inositol,iron,zinc,and probiotics were observed near term in the intervention group.Postpartum mood assessments indicated lower anxiety and depression scores for the intervention group,with significant improvements in the positive and negative affect schedule-now(P=0.002),trait anxiety(P=0.002),and Patient Health Questionnaire-8(P=0.018)scores.The World Health Organization Quality of life Assessment:Brief Version scores improved in the psychological(P=0.041)and environmental(P=0.009)domains postpartum.Fetal biparietal diameter and femoral length were greater in the intervention group alongside better neonatal body length and reduced neonatal unit admissions(2.48%vs 7.84%,P=0.031).CONCLUSION Combined supplementation with myo-inositol,probiotics,and trace elements from preconception through pregnancy may reduce pregnancy-related complications,enhance mood and quality of life,and improve fetal growth metrics. 展开更多
关键词 nutritional interventions retrospective cohort study perinatal depression trace elements PRECONCEPTION PRENATAL preconception prenatal supplementation adjunct therapiesthis
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A trace formula for the vector Sturm-Liouville operator with a constant delay
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作者 LI Dan YANG Chuan-fu 《Applied Mathematics(A Journal of Chinese Universities)》 2025年第1期213-222,共10页
In this work,the vector differential operator with a delay variable is studied and the regularized trace formula of the operator is obtained.
关键词 vector differential operator constant delay trace
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Miocene Pb-Zn Mineralization in the Eastern Gangdese Metallogenic Belt:Evidence from in situ Rb-Sr Dating of Mica and Trace Element Geochemistry of Sphalerite
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作者 ZHAO Xiaoyan YANG Zhusen +2 位作者 LIU Chang DONG Yanrui SHI Haiyan 《Acta Geologica Sinica(English Edition)》 2025年第3期806-821,共16页
Four Pb-Zn deposits,namely Bangpu(BP),Digei(DG),Nabuding(NB)and Cuoga(CG),are located within a 20 km distance of each other in the Gangdese porphyry copper belt(GPCB).The age and nature of the Pb-Zn mineralization,esp... Four Pb-Zn deposits,namely Bangpu(BP),Digei(DG),Nabuding(NB)and Cuoga(CG),are located within a 20 km distance of each other in the Gangdese porphyry copper belt(GPCB).The age and nature of the Pb-Zn mineralization,especially its relationship to magmatism,remain uncertain.In order to address this issue,mica from the four deposits was selected for in situ Rb-Sr dating,with sphalerite additionally being selected for in situ trace element analysis.Detailed geological research has revealed that the BP and NB deposits are primarily skarn-type Pb-Zn mineralization,while DG and CG are associated with magmatic hydrothermal breccia and are characterized by banded-type mineralization.The Rb-Sr isochron ages of syn-mineralization muscovite at the BP and CG deposits are 11±6 Ma and 19.7±0.7 Ma respectively.Fe,Cd,In,Mn and Sn occur as lattice substitutions in sphalerite from the four deposits.Cu exists as microinclusions in BP,but occurs isomorphically in the DG,NB and CG deposits.The formation temperatures of the four deposits,as calculated from sphalerite geothermometry,range from approximately 200℃to 300℃,indicating that they belong to medium temperature deposits.BP and NB are classified as skarn Pb-Zn deposits,while DG and CG are categorized as hydrothermal filled Pb-Zn deposits.These results suggest that,in addition to porphyry Cu mineralization,the GPCB also contains significant Miocene Pb-Zn mineralization. 展开更多
关键词 in situ Rb-Sr dating trace elements SPHALERITE Pb-Zn deposit Gangdese porphyry copper belt
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Multiple-stage W mineralization in the Guanfang W deposit,southeastern Yunnan Province,China:Insights from scheelite in-situ trace elemental and Sr isotopic analyses
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作者 Bin Sun Yi Liu +4 位作者 Zhigang Kong Xuelong Liu Xiaojun Jiang Chao Li Wenchang Li 《Acta Geochimica》 2025年第1期112-127,共16页
The Guanfang large-scale W deposit is located in the W polymetallic ore concentration area of Bozhushan in southeastern Yunnan,China.Despite extensive research,the fluid evolution process of the deposit remains ambigu... The Guanfang large-scale W deposit is located in the W polymetallic ore concentration area of Bozhushan in southeastern Yunnan,China.Despite extensive research,the fluid evolution process of the deposit remains ambiguous,leading to controversy regarding its genesis.This study conducted a detailed field geological survey,with systematic sampling of the KT6 orebody,to delineate mineralization stages.Fine mineralogy work,including the use of CL images of scheelite,in-situ LA-ICP-MS trace elements,and Sr isotopes,was carried out on diff erent generations of scheelite formed in various stages.The findings identified the evolution of fluids in the mineralization process,shedding light on the genesis of the deposit.The study revealed four mineralization stages at the Guanfang W deposit:prograde skarn stage,retrograde skarn stage,quartz-sulfide stage,and carbonate-fluorite stage.Diff erent generations of scheelite(Sch I,Sch II,Sch III)were observed in the first three stages,displaying distinct chondrite-normalized REE patterns.The REE of Sch I mainly substituted into the Ca site by REE^(3+)+□_(Ca),and there may be a similar substitution of Nb for REE,whereas it is not the main substitution method.The REE of Sch II mainly enter the scheelite lattice in the form of REE 3++Na+,and there may be a substitution of Nb for REE isomorphism.In the early stage,The REE of Sch III was mainly replaced by Nb for REE isomorphism,while in the later stage,the replacement mode of REE^(3+)+□_(Ca)coexisted with it.The Mo content in scheelite,along with the corresponding Eu anomalies in both scheelite and garnet,collectively imply that the ore-forming fluids during various mineralization stages were predominantly oxidizing,with only slight reducibility observed in Sch II.The in-situ Sr isotope ratios of scheelite concentrates ranged from 0.7093 to 0.7153,resembling those of the Bozhushan granite,indicating a relationship between W mineralization and granite.In addition,the Y/Ho ratios of scheelite from various mineralization stages exhibit a narrow range(19-31),with a pronounced correlation between the contents of Y and Ho and a similar trend in their variation.This consistency suggests that the Guanfang deposit has undergone a uniform or comparable evolutionary process,implying a stable ore-forming fluid across diff erent mineralization stages. 展开更多
关键词 Guanfang W deposit trace elements of scheelite In-situ Sr isotopes Southeast Yunnan
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Investigation into enhancing the sensitivity method for monitoring trace erosion product concentration in the ceramic channel of a Hall thruster
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作者 Wei XI Ximing ZHU +2 位作者 Bowen ZHENG Zhongxi NING Daren YU 《Plasma Science and Technology》 2025年第4期95-104,共10页
An optical emission spectroscopy(OES)method with a non-invasive measurement capability,without inducing disturbance to the discharge,represents an effective method for material monitoring.However,when the OES method i... An optical emission spectroscopy(OES)method with a non-invasive measurement capability,without inducing disturbance to the discharge,represents an effective method for material monitoring.However,when the OES method is employed to monitor the trace erosion product within the ceramic channel of a Hall thruster,it becomes challenging to distinguish between signal and noise.In this study,we propose a model filtering method based on the signal characteristics of the Hall thruster plume spectrometer.This method integrates the slit imaging and spectral resolution features of the spectrometer.Employing this method,we extract the spectral signals of the erosion product and working gas from the Hall thruster under different operating conditions.The results indicate that our new method performs comparably to the traditional method without model filtering when extracting atom signals from strong xenon working gas.However,for trace amounts of the erosion product,our approach significantly enhances the signal-to-noise ratio(SNR),enabling the identification of extremely weak spectral signals even under low mass flow rate and low-voltage conditions.We obtain boron atom concentration of 3.91×10^(-3) kg/m^(3) at a mass flow rate of 4×10^(-7) kg/s and voltage of 200 V while monitoring a wider range of thruster operating conditions.The new method proposed in this study is suitable for monitoring other low-concentration elements,making it valuable for materials processing,environmental monitoring and space propulsion applications. 展开更多
关键词 model filtering method optical emission spectroscopy Hall thruster advanced actinometry method trace erosion product concentration(Some figures may appear in colour only in the online journal)
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Multi-compartmental migration and ecological-health risks of trace metals in Dexing mining concentration areas:A holistic quantitative assessment
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作者 Xiao-tao Zhang Jun-jie Hu +3 位作者 Bin Shen Man-dan Huang Shan-hong Lan Zhi-hang Xin 《China Geology》 2025年第3期500-513,I0005-I0025,共35页
To address the critical gap in linking multi-compartmental transfer with risks of trace metals(Cd,Pb,As,Cr,Ni)in mining environments.This study systematically investigated the trans-media migration of Cd,Pb,As,Cr,and ... To address the critical gap in linking multi-compartmental transfer with risks of trace metals(Cd,Pb,As,Cr,Ni)in mining environments.This study systematically investigated the trans-media migration of Cd,Pb,As,Cr,and Ni in China’s Dexing copper mining district through paired sampling of water-amphibians,soil-earthworms,and air-lichens.Advanced methodologies were employed,including ICP-MS quantification for heavy metals,geochemical indices(Igeo,BCF,BAF)to assess bioavailability,NMDS for source apportionment,and HPLC to detect DNA methylation alterations.Aquatic systems exhibited severe Cd/Pb enrichment(16.25-24.42μg/L;11-15×WHO limits),while agricultural soils showed extreme Cd contamination(1.5 mg/kg;15×background).Biota displayed metal-specific accumulation:frogs achieved BCFs>1,000 for Pb/Cd,earthworms showed pH-modulated BAFs>2.5 for Cd/As,and lichens recorded 100-1,000×atmospheric Cr enrichment.NMDS resolved three contamination pathways:mining-derived Cd/Pb/As(MDS1=2.56),atmospheric Cr(PC2=1.84),and geogenic Ni.Cd dominated ecological risks(Eri=554.25;RI 300),while atmospheric Cr drove carcinogenic risks(TCR=4.11×10^(-5))exceeding safety thresholds.The source-media-biota-risk framework pioneers the integration of geochemical transport with epigenetic toxicity biomarkers,demonstrating that sub-lethal Cd/Pb exposure induces genome-wide DNA hypomethylation(2.4%-6.6%reduction;ρ=−0.71 to−0.91).This paradigm shift prioritizes bioavailability-informed regulations over concentration-based metrics,offering actionable strategies for sustainable development goals-aligned mining pollution control. 展开更多
关键词 Copper mining operations trace metal(loid)s contamination Cross-media transfer Water-amphibians Soil-earthworms Air-lichens DNA methylation biomarkers Biogeochemical processes Risk assessment Sustainable Development Goals(SDG3) Dexing mining area Environmental geological survey engineering
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基于改进Trace Lasso范数和PALM算法的子空间聚类方法
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作者 药嘉怡 张文娟 +1 位作者 黄姝娟 袁薛程 《内蒙古师范大学学报(自然科学版)》 2025年第1期92-100,共9页
子空间聚类是一类广泛应用的聚类方法,其中最关键的技术是表示矩阵的获取,为使表示矩阵更好地满足块对角结构,提出一种基于改进迹Lasso范数和PALM算法的子空间聚类方法。首先,将原始数据减去噪声所得干净数据作为数据自表示的字典,能够... 子空间聚类是一类广泛应用的聚类方法,其中最关键的技术是表示矩阵的获取,为使表示矩阵更好地满足块对角结构,提出一种基于改进迹Lasso范数和PALM算法的子空间聚类方法。首先,将原始数据减去噪声所得干净数据作为数据自表示的字典,能够促使表示矩阵更接近块对角结构;其次,提出一种改进的迹Lasso范数,利用非凸FCP范数约束矩阵的奇异值向量,能更好促使矩阵满足低秩性;最后,由于提出模型的非凸非光滑性及约束条件的非线性,利用近端交替线性极小化算法求解模型,具有收敛性保证。在CFP人脸数据集和动物面部图像数据集上进行聚类的数值实验表明,提出的子空间聚类方法相比于普遍应用的K‐means聚类、谱聚类及稀疏子空间聚类有更好的聚类性能。 展开更多
关键词 子空间聚类 迹Lasso范数 非凸FCP范数 近端交替线性最小化
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Research on the Responsibility Traceability Mechanism Based on AI and the Application Boundary of Algorithmic Ethics in Medical Decision Making
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作者 Baochen Huang Zhikai Huang 《Proceedings of Business and Economic Studies》 2025年第4期280-298,共19页
With the rapid advancement of medical artificial intelligence(AI)technology,particularly the widespread adoption of AI diagnostic systems,ethical challenges in medical decision-making have garnered increasing attentio... With the rapid advancement of medical artificial intelligence(AI)technology,particularly the widespread adoption of AI diagnostic systems,ethical challenges in medical decision-making have garnered increasing attention.This paper analyzes the limitations of algorithmic ethics in medical decision-making and explores accountability mechanisms,aiming to provide theoretical support for ethically informed medical practices.The study highlights how the opacity of AI algorithms complicates the definition of decision-making responsibility,undermines doctor-patient trust,and affects informed consent.By thoroughly investigating issues such as the algorithmic“black box”problem and data privacy protection,we develop accountability assessment models to address ethical concerns related to medical resource allocation.Furthermore,this research examines the effective implementation of AI diagnostic systems through case studies of both successful and unsuccessful applications,extracting lessons on accountability mechanisms and response strategies.Finally,we emphasize that establishing a transparent accountability framework is crucial for enhancing the ethical standards of medical AI systems and protecting patients’rights and interests. 展开更多
关键词 Algorithmic ethics Medical decision-making Liability tracing Medical AI Patient rights protection
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