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DNMKG: A method for constructing domain of nonferrous metals knowledge graph based on multiple corpus
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作者 Hai-liang LI Hai-dong WANG 《Transactions of Nonferrous Metals Society of China》 2025年第8期2790-2802,共13页
To address the underutilization of Chinese research materials in nonferrous metals,a method for constructing a domain of nonferrous metals knowledge graph(DNMKG)was established.Starting from a domain thesaurus,entitie... To address the underutilization of Chinese research materials in nonferrous metals,a method for constructing a domain of nonferrous metals knowledge graph(DNMKG)was established.Starting from a domain thesaurus,entities and relationships were mapped as resource description framework(RDF)triples to form the graph’s framework.Properties and related entities were extracted from open knowledge bases,enriching the graph.A large-scale,multi-source heterogeneous corpus of over 1×10^(9) words was compiled from recent literature to further expand DNMKG.Using the knowledge graph as prior knowledge,natural language processing techniques were applied to the corpus,generating word vectors.A novel entity evaluation algorithm was used to identify and extract real domain entities,which were added to DNMKG.A prototype system was developed to visualize the knowledge graph and support human−computer interaction.Results demonstrate that DNMKG can enhance knowledge discovery and improve research efficiency in the nonferrous metals field. 展开更多
关键词 knowledge graph nonferrous metals THESAURUS word vector model multi-source heterogeneous corpus
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Associations of multiple metals exposure with immunoglobulin levels in pregnant women:Hangzhou Birth Cohort Study
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作者 Jiena Zhou Lanfei Jin +13 位作者 Yexinyi Zhou Kunhong Zhong Kegui Huang Qi Zhang Jun Tang Xue Zhang Lihe Peng Shuai Li Na Lv Dongdong Yu Qinheng Zhu Jing Guo Qiong Luo Guangdi Chen 《Journal of Environmental Sciences》 2025年第5期560-572,共13页
Metal may affect maternal immune function,but few epidemiological studies have reported the associations between multiple-metal exposure and maternal immunoglobulin(Ig)levels.Based on the Hangzhou Birth Cohort Study,1... Metal may affect maternal immune function,but few epidemiological studies have reported the associations between multiple-metal exposure and maternal immunoglobulin(Ig)levels.Based on the Hangzhou Birth Cohort Study,1059 participants were included,and eleven metals in whole blood samples and serum IgA,IgG,IgE and IgM levels were measured.Linear regression,quantile-based g-computation(QGC),and Bayesian kernel machine regression(BKMR)models were used to evaluate the associations.Compared with the first tertile of metal levels,arsenic(As)was negatively associated with IgE(β=-0.25,95%confidence interval(CI)=-0.48 to-0.02).Moreover,significant associations of manganese(Mn)with IgA,IgG and IgM were demonstrated(β=0.10,95%CI=0.04 to 0.18;β=0.07,95%CI=0.03 to 0.12;β=0.10,95%CI=0.03 to 0.18,respectively).Cadmium(Cd)were associated with higher levels of IgM.QGC models showed the positive association of the metalmixtures with IgA and IgG,with Mn playing amajor role.Mn and Cd had positive contributions to IgM,while As had negative contributions to IgE.In the BKMR models,the latent continuous outcomes of IgA and IgG showed a significant increase when all the metals were at their 60th percentile or above compared to those at their 50th percentile.Therefore,exposure to metals was associated with maternal Igs,and mainly showed that Mn was associated with increased levels of IgA,IgG and IgM,and As was associated with low IgE levels. 展开更多
关键词 metals IMMUNOGLOBULIN Pregnant woman Quantile-based g-computation (QGC) Bayesian kernel machine regression (BKMR)
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Relationship of Non-Essential and Essential Metals with Vitamin D in a Chinese Early Adolescent Cohort
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作者 Gengfu Wang Weibo Liu +9 位作者 Min Li Ting Tang Qi Zhong Guangbo Qu Yi Zhou Mengyuan Yuan Yonghan Li Fangbiao Tao Puyu Su Chaoxue Zhang 《Biomedical and Environmental Sciences》 2026年第1期116-122,共7页
Vitamin D deficiency(VDD)represents a significant nutritional concern among children and adolescents.The estimated prevalence of VDD in China is 46.8%in this population^([1]).VDD during childhood and adolescence has b... Vitamin D deficiency(VDD)represents a significant nutritional concern among children and adolescents.The estimated prevalence of VDD in China is 46.8%in this population^([1]).VDD during childhood and adolescence has been associated with the onset of various conditions,including acute respiratory infections,asthma,atopic dermatitis,and food allergies^([2]).Multiple factors,including age,sun exposure,adiposity,and genetics,influence vitamin D levels^([2,3]).Increasing attention has been directed toward understanding the environmental determinants that may influence vitamin D status.Given the potential of metallic pollutants to disrupt endocrine function and their ubiquity in the environment,investigating the effects of metal exposure on human vitamin D status,particularly in vulnerable populations,is imperative. 展开更多
关键词 vitamin d deficiency vdd represents Chinese early adolescent cohort essential metals vitamin d non essential metals food allergies multiple acute respiratory infectionsasthmaatopic dermatitisand vitamin D deficiency
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Illusion of inactivity:Revisiting progressive multiple sclerosis treatment paradigms
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作者 Tal Ganz Tamir Ben-Hur 《Neural Regeneration Research》 2026年第3期1134-1135,共2页
Active inflammation in“inactive”progressive multiple sclerosis:Traditionally,the distinction between relapsing-remitting multiple sclerosis and progressive multiple sclerosis(PMS)has been framed as an inflammatory v... Active inflammation in“inactive”progressive multiple sclerosis:Traditionally,the distinction between relapsing-remitting multiple sclerosis and progressive multiple sclerosis(PMS)has been framed as an inflammatory versus degenerative dichotomy.This was based on a broad misconception regarding essentially all neurodegenerative conditions,depicting the degenerative process as passive and immune-independent occurring as a late byproduct of active inflammation in the central nervous system(CNS),which is(solely)systemically driven. 展开更多
关键词 inflammatory versus degenerative dichotomythis treatment paradigms illusion inactivity multiple sclerosis traditionallythe central nervous system cns which progressive multiple sclerosis active inflammation progressive multiple sclerosis pms
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Nanoparticle assisted phytoremediation:An eco-friendly approach for removal of heavy metals from the environment
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作者 Sakshi Sharma Ritika Dadhwal Ritesh Banerjee 《Journal of Environmental Sciences》 2026年第1期705-720,共16页
The surge in environmental pollution in recent years driven by numerous pollutants has necessitated the search for efficient removal methods.Phytoremediation is an eco-friendly technique that provides multiple benefit... The surge in environmental pollution in recent years driven by numerous pollutants has necessitated the search for efficient removal methods.Phytoremediation is an eco-friendly technique that provides multiple benefits over conventional methods of removing contaminants.Despite the numerous benefits of this technique,it has certain limitations that can be addressed by incorporating nanoparticles to improve its effectiveness.This review paper aims to explore the impact of heavy metal pollution on plants and human health.It highlights the role and mechanism of nanoparticles in enhancing phytoremediation,their application in the detection of heavy metals,and the strategies for the safe disposal of phytoremediation biomass.Biosynthesized nanoparticles are eco-friendly and non-toxic,with applications in biomedical and environmental fields.Nanoparticles can be used in the form of nano biosensors like smartphone-operated wireless sensors made from Cinnamomum camphora,enabling efficient detection of heavy metal ions.According to the studies,nanoparticles remove 80%–97%of heavy metals by various methods like reduction,precipitation,adsorption,etc.The phytoremediation biomass disposal can be done by heat treatment,phytomining,and microbial treatment with some modifications to further enhance their results.Phytoremediation is an environmentally friendly technique but requires further research and integration with biomass energy production to overcome scalability challenges and ensure safe biomass disposal. 展开更多
关键词 PHYTOREMEDIATION Heavy metals Nanoparticles Environmental contamination Postharvest biomass management
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Predicting lymph node metastasis in colorectal cancer using caselevel multiple instance learning
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作者 Ling-Feng Zou Xuan-Bing Wang +4 位作者 Jing-Wen Li Xin Ouyang Yi-Ying Luo Yan Luo Cheng-Long Wang 《World Journal of Gastroenterology》 2026年第1期110-125,共16页
BACKGROUND The accurate prediction of lymph node metastasis(LNM)is crucial for managing locally advanced(T3/T4)colorectal cancer(CRC).However,both traditional histopathology and standard slide-level deep learning ofte... BACKGROUND The accurate prediction of lymph node metastasis(LNM)is crucial for managing locally advanced(T3/T4)colorectal cancer(CRC).However,both traditional histopathology and standard slide-level deep learning often fail to capture the sparse and diagnostically critical features of metastatic potential.AIM To develop and validate a case-level multiple-instance learning(MIL)framework mimicking a pathologist's comprehensive review and improve T3/T4 CRC LNM prediction.METHODS The whole-slide images of 130 patients with T3/T4 CRC were retrospectively collected.A case-level MIL framework utilising the CONCH v1.5 and UNI2-h deep learning models was trained on features from all haematoxylin and eosinstained primary tumour slides for each patient.These pathological features were subsequently integrated with clinical data,and model performance was evaluated using the area under the curve(AUC).RESULTS The case-level framework demonstrated superior LNM prediction over slide-level training,with the CONCH v1.5 model achieving a mean AUC(±SD)of 0.899±0.033 vs 0.814±0.083,respectively.Integrating pathology features with clinical data further enhanced performance,yielding a top model with a mean AUC of 0.904±0.047,in sharp contrast to a clinical-only model(mean AUC 0.584±0.084).Crucially,a pathologist’s review confirmed that the model-identified high-attention regions correspond to known high-risk histopathological features.CONCLUSION A case-level MIL framework provides a superior approach for predicting LNM in advanced CRC.This method shows promise for risk stratification and therapy decisions,requiring further validation. 展开更多
关键词 Colorectal cancer Lymph node metastasis Deep learning multiple instance learning HISTOPATHOLOGY
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Simultaneous immobilization of multiple heavy metal(loid)s in contaminated water and alkaline soil inoculated Fe/Mn oxidizing bacterium 被引量:1
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作者 Yi Wu Shengli Wang +5 位作者 Jun Xu Fei Zang Song Long Yining Wu Yuqing Wang Zhongren Nan 《Journal of Environmental Sciences》 2025年第1期370-381,共12页
Two strains of Fe/Mn oxidizing bacteria tolerant to high concentrations of multiple heavy metal(loid)s and efficient decontamination for them were screened.The surface of the bio-Fe/Mn oxides produced by the oxidation... Two strains of Fe/Mn oxidizing bacteria tolerant to high concentrations of multiple heavy metal(loid)s and efficient decontamination for them were screened.The surface of the bio-Fe/Mn oxides produced by the oxidation of Fe(II)and Mn(II)by Pseudomonas taiwanensis(marked as P4)and Pseudomonas plecoglossicida(marked as G1)contains rich reactive oxygen functional groups,which play critical roles in the removal efficiency and immobilization of heavymetal(loid)s in co-contamination system.The isolated strains P4 and G1 can growwell in the following environments:pH 5-9,NaCl 0-4%,and temperature 20-30℃.The removal efficiencies of Fe,Pb,As,Zn,Cd,Cu,and Mn are effective after inoculation of the strains P4 and G1 in the simulated water system(the initial concentrations of heavy metal(loid)were 1 mg/L),approximately reaching 96%,92%,85%,67%,70%,54%and 15%,respectively.The exchangeable and carbonate bound As,Cd,Pb and Cu are more inclined to convert to the Fe-Mn oxide bound fractions in P4 and G1 treated soil,thereby reducing the phytoavailability and bioaccessible of heavy metal(loid)s.This research provides alternatives method to treat water and soil containing high concentrations of multi-heavy metal(loid)s. 展开更多
关键词 Bio-Fe/Mn oxides PSEUDOMONAS Heavy metal(loid)s Removal and immobilization
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Preparation and Electrochemical Performance of N-doped Carbon Nanospheres Supported Multiple Transition Metal Sulfides Electrocatalyst
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作者 Shuo Yan Zhiqing Ge +4 位作者 Xiangyu Shen Baoying Zhang Shouqun Zhang Mozhen Wang Xuewu Ge 《Chinese Journal of Chemical Physics》 2025年第6期926-938,I0185-I0190,I0240,共20页
The design and preparation of economic and efficient electrolysis water catalysts is an important part in effectively developing and utilizing hydrogen energy.In this work,novel N-doped carbon nanospheres supported mu... The design and preparation of economic and efficient electrolysis water catalysts is an important part in effectively developing and utilizing hydrogen energy.In this work,novel N-doped carbon nanospheres supported multiple transition metal sulfides(NiWCoS/NC)electrocatalysts were prepared by combining the radiation oxidation synthesis and synchronous carbonization-sulfurization.Initially,the precursor material(NiWCoS/OANI,here OANI refers to oligoaniline)containing sulfurand multiple transition metal(Ni,W,and Co)ions loaded on oligoaniline nanospheres was directly one-pot synthesized at room temperature under γ-ray radiation.Subsequently,NiWCoS/NC electrocatalysts were successfully prepared by calcining the NiWCoS/OANI precursor at 800℃.The electrocatalytic performance of NiWCoS/NC for the hydrogen evolution reaction(HER)and oxygen evolution reaction(OER)was characterized by electrochemical analysis methods including linear sweep voltammetry,cyclic voltammetry,chronoamperometry,and electrochemical impedance spectroscopy.The influence of the relative content of the loaded transition metals on the electrocatalytic performance was also investigated.The results indicate that the novel NiWCoS/NC electrocatalyst can significantly reduce the overpotential and Tafel slope for both HER and OER compared to corresponding electrocatalysts with single metal or metal sulfide component.When NiWCoS/NC with a molar ratio of 3:6:10 for W,Co,and S elements was used as electrode material,the overpotentials for HER in 0.5 mol/L H_(2)SO_(4) and OER in 1 mol/L KOH are only 161 mV and 243 mV at a current density of 10 mA/cm^(2),respectively.The Tafel slopes are 74 mV/dec and 88 mV/dec,respectively.The work provides a new direction and method for the design and green facile preparation of high-efficiency overall water splitting catalysts. 展开更多
关键词 multiple transition metal sulfide Radiation oxidation and redox OLIGOANILINE N-doped carbon nanospheres Overall water splitting electrocatalyst
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APOEε4 Allele Modifies the Association of Heavy Metals and their Mixture with Diabetes Mellitus among Chinese Community-Dwelling Older Adults
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作者 Lili Yao Ying Cao +10 位作者 Beibei Yin Qiang Liu Fusheng Lin Xuqiu Cheng Ziwei Tian Linsheng Yang Hongjuan Cao Liang Sun Fangbiao Tao Li Wang Guimei Chen 《Biomedical and Environmental Sciences》 2026年第1期123-128,共6页
In 2021,approximately 537 million people suffered from diabetes mellitus(DM)globally,and this figure will increase to approximately 783 million within the next quarter-century.The increasing burden of DM is a pressing... In 2021,approximately 537 million people suffered from diabetes mellitus(DM)globally,and this figure will increase to approximately 783 million within the next quarter-century.The increasing burden of DM is a pressing global public health issue.Therefore,the early identification of high-risk groups and implementation of effective intervention measures is imperative. 展开更多
关键词 effective intervention measures heavy metals Chinese community dwelling older adults global public health issue diabetes mellitus dm globallyand APOE allele diabetes mellitus early identification
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Multiple host-vip and metal coordination interactions induce supramolecular assembly and structural transition
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作者 Shengyong Liu Hui Li +3 位作者 Wei Zhang Yan Zhang Yan Dong Wei Tian 《Chinese Chemical Letters》 2025年第6期468-472,共5页
Three monomers,namely A2,B2,and GH,were designed and synthesized.By utilizing double host-vip interactions,the monomers A2+B2+GH underwent self-assembly to form a supramolecular linear polymer(SLP)at high concentrat... Three monomers,namely A2,B2,and GH,were designed and synthesized.By utilizing double host-vip interactions,the monomers A2+B2+GH underwent self-assembly to form a supramolecular linear polymer(SLP)at high concentrations.Long fibers could be pulled from the concentrated SLP solution.Upon the addition of PdCl_(2)(PhCN)_(2)into the SLP solution,a structural transformation occurred from SLP to a supramolecular crosslinked polymer(SCP)through metal coordination interaction.This transformation induced fluorescence quenching,test paper strips for ion detection experiment confirmed that the SLP had good detection ability for Pd^(2+).Furthermore,the SCP underwent a transformation into a gel when the concentration exceeded 145 mmol/L.The SCP gel demonstrated sensitivity to different stimuli,such as K^(+)ions and changes in temperature,accompanied by a reversible transition between sol and gel states.Additionally,rheological analyses indicated that the gel possessed favorable self-healing properties. 展开更多
关键词 SELF-ASSEMBLY Supramolecular chemistry Macrocycles Host-vip interaction metal coordination
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Influence factors analysis of removing heavy metals from multiple metal-contaminated soils with different extractants 被引量:6
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作者 夏文斌 李 欣 +5 位作者 高 慧 黄宝荣 张慧智 刘云国 曾光明 樊 霆 《Journal of Central South University》 SCIE EI CAS 2009年第1期108-111,共4页
Some key factors on the heavy metals removal efficiencies were studied when soil washing technology was used in the remediation of soils contaminated by multiple heavy metals. The results show that the dissolubilities... Some key factors on the heavy metals removal efficiencies were studied when soil washing technology was used in the remediation of soils contaminated by multiple heavy metals. The results show that the dissolubilities of Cu and Zn are promoted by humic acids, but Pb and Cd are inhibited by humic acids; heavy metals in the clay are more difficult to be extracted than silt; the strong acidic soils can cause the protonation of EDTA and weaken its extracting ability; EDTA is effective for extracting Pb and Cd, while oxalate (OX) is effective for extracting Cu and Zn; and biosurfactant can be used as additive to improve the removal of some particular heavy metals. 展开更多
关键词 heavy metal soil remediation EXTRACTION RHAMNOLIPID
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Multiple transition metals modulated hierarchical networks for high performance of metal-ion batteries 被引量:1
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作者 Jie Liu Chenjie Lou +8 位作者 Jipeng Fu Xuan Sun Jingrong Hou Jiwei Ma Yongjin Chen Xiang Gao Ligang Xu Qi Wei Mingxue Tang 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2022年第7期604-613,I0015,共11页
Searching anodes with excellent electrochemical performance has been in great demand for rechargeable metal ion batteries. In this contribution, Fe/Co co-doped Ni S with N-based carbon(Fe Co-NiS@NC) derived from trime... Searching anodes with excellent electrochemical performance has been in great demand for rechargeable metal ion batteries. In this contribution, Fe/Co co-doped Ni S with N-based carbon(Fe Co-NiS@NC) derived from trimetallic Prussian blue analogue is designed and synthesized. The composition can be easily adjusted and modulated by multi-metals. In addition, the well-designed carbon nanocubes effectively promote electronic conductivity and buffer the volume change upon charge and discharge cycling, resulting in good capacity and long-term cycle life for both lithium-ion batteries and sodium-ion batteries, with capacities of 1018 m Ah g^(-1)(vs. Li/Li^(+)) and 454 m Ah g^(-1)(vs. Na/Na^(+)), respectively, after 100 cycles.Kinetics studies indicate that the electrochemical behaviors are manipulated by both diffusion and pseudocapacitance processes. These strategies would open new opportunities and potention for novel energy storage. 展开更多
关键词 multiple transition metallic synergy Li-ion batteries Solium-ion batteries In-situ XRD Long-term cycling stability High coulumbic efficiency
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Fixation of Multiple Metals in Contaminated Soil by Different Passivators 被引量:3
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作者 WANG Hui XU Chao +5 位作者 OUYANG Dong-sheng WANG Shuai LV Guang-hui LUO Zun-chang LIAO Yu-lin ZHU Han-hua 《Agricultural Science & Technology》 CAS 2018年第6期24-30,共7页
The effects of 4 passivators, zeolite, lime, red mud and peanut shell biochar, on the fixation of Cd, Pb, Cu and Zn in acidic multi-metal contaminated soils were studied by passivator culture experiment in order to sc... The effects of 4 passivators, zeolite, lime, red mud and peanut shell biochar, on the fixation of Cd, Pb, Cu and Zn in acidic multi-metal contaminated soils were studied by passivator culture experiment in order to screen out the passivator with better fixation effects. The results showed that the soil pH values of zeolite, lime, red mud and peanut shell biochar increased significantly by 0.511.02, 0.821.29, 0.720.89 and 0.300.35 respectively. The effects of 4 passivators on the fixation of Cd and Zn in soil are lime>red mud>zeolite>peanut shell biochar. The order of effects on the fixation of Pb is red mud>lime>zeolite>peanut shell biochar. The order of the fixation effects of Cu is red mud>lime>peanut shell carbon>zeolite. The contents of Cd, Pb, Cu and Zn in the extractable state of CaCl2 decreased with the increase in the dosage of 4 passivators. Lime and red mud showed good fixation effects on Cd, Pb, Cu and Zn. The contents of Cd, Pb, Cu and Zn in the extractable state of CaCl2 at the low dosage(2.5 g/kg) of lime and red mud decreased by 41%, 84%, 76% and 83% respectively. Soil pH value was negatively correlated with CaCl2-Cd, Pb, Cu and Zn(P<0.01). Lime and red mud had significant fixation effects on Cd, Pb, Cu and Zn in acidic multi-metal contaminated soils at low application dosages. 展开更多
关键词 Effectiveness of heavy metals Compound pollution PASSIVATOR Chemical fixation
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Comparison of Heavy Metal Accumulation in Four Vegetables Grown in the Soils Contaminated with Multiple Heavy Metals 被引量:1
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作者 XIONG Wen-ming LI Yong-jun +2 位作者 MO Gui-ming ZHOU Jia-cheng XIE Cai-ling 《Agricultural Science & Technology》 CAS 2022年第4期25-32,共8页
In order to compare the differences in the accumulation of plumbum(Pb),cadmium(Cd),chromium(Cr),cuprum(Cu),nickel(Ni)and zinc(Zn)from the multi-contaminated,alkalescent soil in the plants of four-season big-leaf coria... In order to compare the differences in the accumulation of plumbum(Pb),cadmium(Cd),chromium(Cr),cuprum(Cu),nickel(Ni)and zinc(Zn)from the multi-contaminated,alkalescent soil in the plants of four-season big-leaf coriander,butter lettuce,four-season fast-growing pakchoi and four-season parsley to choose low accumulation vegetables,a pot experiment was conducted by using heavy metal salts to simulate high-,moderate-and low-level heavy metals multi-contaminated soils.The results showed that the multi-contaminated soil by high levels of Pb,Cd,Cr,Cu and Zn produced inhibition on biomass of four-season fast-growing pakchoi,failing to collect samples,but had no obvious inhibition on the growth of the three other vegetables.Among the four kinds of vegetables examined,the accumulation ability of four-season parsley to the five heavy metals of Pb,Cd,Cr,Cu and Zn was the strongest,while the accumulation ability of four-season fast-growing pakchoi to Ni was the strongest.In the high-level contaminated soil,the underground part of these four vegetables grown was more likely to accumulate heavy metals than their aboveground part.Both of vegetable varieties and heavy metal types can affect the accumulation of heavy metals in vegetables.Our research also found that four-season big-leaf coriander was high yielding and low accumulation of heavy metals. 展开更多
关键词 VEGETABLES Combined contamination Soil Pot experiments Heavy metals accumulation
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Assessment of Dietary Exposure and Health Risk to Multiple Heavy Metals amongst Some Workers in Yaounde, Cameroon
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作者 Angele N. Tchana Nina D. Kamnang +5 位作者 Arielle T. Maliedje Faustin T. Manfo Frederic N. Nj ayou Wilfred A. Abia Edouard A. Nantia Paul F. Moundipa 《Journal of Pharmacy and Pharmacology》 2018年第9期801-816,共16页
This study reports on the dietary exposure of people in Yaounde, Cameroon to heavy metals: lead (Pb), cadmium (Cd), mercury (Hg), copper (Cu) and zinc (Zn). One hundred and fifty table-ready food, water and... This study reports on the dietary exposure of people in Yaounde, Cameroon to heavy metals: lead (Pb), cadmium (Cd), mercury (Hg), copper (Cu) and zinc (Zn). One hundred and fifty table-ready food, water and soft drink samples were collected from households and street restaurants in Yaounde and analyzed for heavy metals contents using atomic absorption spectrophotometer. Lead (93%, range 0.019-1.77 ppm), Cd (70%, range 0.01-4.68 ppm), Hg (81%, range 0.03-10.56 ppm), Cu (90%, range 0.004-40.32 ppm) and Zn (87%, range 0.014-2,447.04 ppm) were detected in studied samples. Maximum level of each metal exceeded its corresponding European Commissions legislative limits. Samples from street restaurants were most tainted with heavy metals. The highest average daily intakes (ADIs) of Pb (0.96 mg/day) and Hg (1.84 mg/day) were through tap water, while Cd (1.15 mg/day), Cu (5.42 mg/day) and Zn (601.6 mg/day) were through rice/peanut sauce mixed food. The ADI for Cd and Hg was each higher than its respective PTDI (provisional tolerable daily intake) as defined by JECFA (Joint FAO/WHO Expert Committee on Food Additives) and EVM (Expert Group on Vitamins and Minerals). The estimated average daily exposure dose of each detected metal significantly (p = 0.001) exceeded its corresponding PTDI. However, the health risk index was 〈 1 for all studied samples and it was found to be safe, indicating there is a relative absence of health risks associated with the ingestion of contaminated foods, water and soft drinks. Notwithstanding, the detected levels and ADI being higher than legislative limits and PTDI respectively speculates need for awareness raising towards reducing exposure levels to heavy metals in Cameroon. 展开更多
关键词 Dietary exposure FOOD water and soft drink contamination heavy metals Cameroon
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Design Guidelines for Composition of Brazing Filler Metals and Evolution Mechanisms of Typical Microstructures 被引量:6
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作者 Long Weimin 《稀有金属材料与工程》 北大核心 2025年第4期837-853,共17页
Brazing filler metals are widely applied,which serve as an industrial adhesive in the joining of dissimilar structures.With the continuous emergence of new structures and materials,the demand for novel brazing filler ... Brazing filler metals are widely applied,which serve as an industrial adhesive in the joining of dissimilar structures.With the continuous emergence of new structures and materials,the demand for novel brazing filler metals is ever-increasing.It is of great significance to investigate the optimized composition design methods and to establish systematic design guidelines for brazing filler metals.This study elucidated the fundamental rules for the composition design of brazing filler metals from a three-dimensional perspective encompassing the basic properties of applied brazing filler metals,formability and processability,and overall cost.The basic properties of brazing filler metals refer to their mechanical properties,physicochemical properties,electromagnetic properties,corrosion resistance,and the wettability and fluidity during brazing.The formability and processability of brazing filler metals include the processes of smelting and casting,extrusion,rolling,drawing and ring-making,as well as the processes of granulation,powder production,and the molding of amorphous and microcrystalline structures.The cost of brazing filler metals corresponds to the sum of materials value and manufacturing cost.Improving the comprehensive properties of brazing filler metals requires a comprehensive and systematic consideration of design indicators.Highlighting the unique characteristics of brazing filler metals should focus on relevant technical indicators.Binary or ternary eutectic structures can effectively enhance the flow spreading ability of brazing filler metals,and solid solution structures contribute to the formability.By employing the proposed design guidelines,typical Ag based,Cu based,Zn based brazing filler metals,and Sn based solders were designed and successfully applied in major scientific and engineering projects. 展开更多
关键词 design of brazing filler metals design guidelines for composition Ag based brazing filler metals eutectic structures evolution
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Infiltration by monocytes of the central nervous system and its role in multiple sclerosis: reflections on therapeutic strategies 被引量:1
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作者 Guangyong Zhang Qing Yao +9 位作者 Chubing Long Pengcheng Yi Jiali Song Luojia Wu Wei Wan Xiuqin Rao Yue Lin Gen Wei Jun Ying Fuzhou Hua 《Neural Regeneration Research》 SCIE CAS 2025年第3期779-793,共15页
Mononuclear macrophage infiltration in the central nervous system is a prominent feature of neuroinflammation. Recent studies on the pathogenesis and progression of multiple sclerosis have highlighted the multiple rol... Mononuclear macrophage infiltration in the central nervous system is a prominent feature of neuroinflammation. Recent studies on the pathogenesis and progression of multiple sclerosis have highlighted the multiple roles of mononuclear macrophages in the neuroinflammatory process. Monocytes play a significant role in neuroinflammation, and managing neuroinflammation by manipulating peripheral monocytes stands out as an effective strategy for the treatment of multiple sclerosis, leading to improved patient outcomes. This review outlines the steps involved in the entry of myeloid monocytes into the central nervous system that are targets for effective intervention: the activation of bone marrow hematopoiesis, migration of monocytes in the blood, and penetration of the blood–brain barrier by monocytes. Finally, we summarize the different monocyte subpopulations and their effects on the central nervous system based on phenotypic differences. As activated microglia resemble monocyte-derived macrophages, it is important to accurately identify the role of monocyte-derived macrophages in disease. Depending on the roles played by monocyte-derived macrophages at different stages of the disease, several of these processes can be interrupted to limit neuroinflammation and improve patient prognosis. Here, we discuss possible strategies to target monocytes in neurological diseases, focusing on three key aspects of monocyte infiltration into the central nervous system, to provide new ideas for the treatment of neurodegenerative diseases. 展开更多
关键词 blood–brain barrier MACROPHAGES MONOCYTES multiple sclerosis NEUROINFLAMMATION review therapy
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Multiple Antibiotic Resistance and Heavy Metal Resistance Profile of Bacteria Isolated from Giant Freshwater Prawn (Macrobrachium rosenbergii) Hatchery 被引量:7
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作者 S W Lee M Najiah +2 位作者 W Wendy A Zahrol M Nadirah 《Agricultural Sciences in China》 CAS CSCD 2009年第6期740-745,共6页
In this article, antibiogram and heavy metal resistance profile of bacteria isolated from giant freshwater prawn (Macrobrachium rosenbergii) hatchery in Malaysia are described. Although giant freshwater prawn was in... In this article, antibiogram and heavy metal resistance profile of bacteria isolated from giant freshwater prawn (Macrobrachium rosenbergii) hatchery in Malaysia are described. Although giant freshwater prawn was introduced into Malaysia since the 1980s, there was no database information on antibiogram and heavy metal resistance profile of bacteria from giant freshwater prawn (34. rosenbergii) hatchery in Malaysia. Therefore, this study was carried out to determine the effectiveness of antibiotic and heavy metal resistance profile to control bacterial diseases in M. rosenbergii hatchery. The results can provide valuable information for local M. rosenbergii post-larval producer. Antibiotic sensitivity test was carried out by disk-diffusion method against 15 types of antibiotics as follows: oxolinic acid (2 μg), ampicillin (10μg), erythromycin (15μg), furazolidone (15 μg), lincomycin (15μg), amoxicillin (25 μg), colistin sulphate (25 μg), doxycycline (30μg), florfenicol (30 μg), flumequine (30 lag), nalidixic acid (30μg), tetracycline (30μg), oleandomycin (15μg), fosfomycin (50μg), and spiramycin (100 μg), whereas heavy metal resistance profile of the present bacterial isolates was determined by 2-fold agar dilution technique. In this study, 5 types of bacteria were successfully isolated; they were Aeromonas spp. (n = 77), Escherichia coli (n = 73), Edwardsiella spp. (n = 62), Salmonella spp. (n = 75), and Vibrio spp. (n = 43). The result showed that furazolidone was the most effective antibiotic to control the bacteria isolated in this study, approximately 89.7% of the bacterial isolates were sensitive to this antibiotic. Multiple antibiotic resistance (MAR) index indicated that the hatchery water source and M. rosenbergii post-larval and sediment tanks were at high-risk exposure to the tested antibiotic. Furthermore, all the tested heavy metals (Cd2+, Cr6+, Hg2+, and Cu2+) failed to inhibit the growth of the bacterial isolates. Therefore, it indicated that the water source of the hatchery is contaminated with both antibiotic residues and heavy metal. 展开更多
关键词 Macrobrachium rosenbergii HATCHERY antibiotic heavy metal MAR index
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Effect of Multiple Forging on Microstructure and Mechanical Properties of Powder Metallurgy FGH4096 Superalloy 被引量:6
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作者 NING Yongquan YAO Zekun +2 位作者 GUO Hongzhen TAO Yu ZHANG Yiwen 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2009年第6期925-929,共5页
FGH4096 is an important damage-tolerance-type powder metallurgy (PM) superalloy, which is also the optimized turbine material for high performance aero-engine. To turbine disc, bore and rim are used in high temperat... FGH4096 is an important damage-tolerance-type powder metallurgy (PM) superalloy, which is also the optimized turbine material for high performance aero-engine. To turbine disc, bore and rim are used in high temperature-low stress condition and low temperature-high stress condition, and dual-microstructure is introduced. Coarse-grained microstructure is suit for rim region and fine-grained is no doubt most suitable for bore region. But fine-grained ingot can not make by PM technique, so that gradient heat treatment can not be developed to coarsen the grain of rim region. Under the confine of PM technique, several treatment processir, g should be taken place to refine the coarse grains of PM alloy. Multiple forging with large accumulate deformation was carried cat on PM FGH4096 superalloy, and fine grains of 3.5 μm were obtained by this treatment processing. Mechanical properties testing were ake carried out on both fine-grained and other statuses alloys, Microstrucmre evolution was observed by optical microscopy, scanning electron microscopy and transmission electron microscopy. As a result of repeated dynamic recrystallizafion, coarse grains could be completely refined into fine grains. And the increase of strength was mainly attributed to refinement effect and improvement of defects such as previous particle boundaries. Successful development of fine-grained treatment processing will promote the research of dual-microstructure turbine disc. 展开更多
关键词 FGH4096 superalloy multiple forging FINE-GRAINED dynamic recrystallization refine mechanism strengthening mechanism
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Sorption Characteristics for Multiple Adsorption of Heavy Metal Ions Using Activated Carbon from Nigerian Bamboo 被引量:5
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作者 Ademiluyi Falilat Taiwo Nze Jane Chinyere 《Journal of Materials Science and Chemical Engineering》 2016年第4期39-48,共10页
Sorption characteristics of multiple adsorption of six heavy metal ions often found in refinery waste waters using activated carbon from Nigerian bamboo was investigated. The bamboo was cut, washed and dried. It was c... Sorption characteristics of multiple adsorption of six heavy metal ions often found in refinery waste waters using activated carbon from Nigerian bamboo was investigated. The bamboo was cut, washed and dried. It was carbonized between 350℃ - 500℃, and activated at 800℃ using nitric acid. Simultaneous batch adsorption of different heavy metal ions (Cd<sup>2+</sup>, Ni<sup>2+</sup>, Pb<sup>2+</sup>, Cr<sup>3+</sup>, Cu<sup>2+</sup> and Zn<sup>2+</sup>) in same aqueous solution using activated carbon from Nigerian bamboo was carried out. The adsorption process had a better fit for the Freundlich, Temkin isotherm and Dubinin-Radushke-vich (DRK) isotherm models but could not fit well into Langmuir isotherm. Adsorption isotherms showed that there is competition among various metals for adsorption sites on Nigerian bamboo. The DRK model was used to determine the nature of the sorption process and was found to be physical and chemical, with sorption energy of metal ions ranging from (7 - 10 kJ/mol). The adsorption of Cd<sup>2+</sup>, Zn<sup>2+</sup>, Pb<sup>2+</sup> and Ni<sup>2+</sup> ions was chemisorptions and that of Cu<sup>2+</sup> and Cr<sup>3+</sup> ions was cooperative adsorption. Therefore, this study revealed that Nigerian bamboo can serve as a good source of activated carbon with multiple and simultaneous metalions—removing potentials and may serve as a better replacement for commercial activated carbons in applications that warrant their use. 展开更多
关键词 multiple Batch Adsorption Heavy metal Ions Activated Carbon Nigerian Bamboo
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