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Dynamics and genetic regulation of macronutrient concentrations during grain development in maize 被引量:1
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作者 Pengcheng Li Shuangyi Yin +7 位作者 Yunyun Wang Tianze Zhu Xinjie Zhu Minggang Ji Wenye Rui Houmiao Wang Chenwu Xu Zefeng Yang 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2024年第3期781-794,共14页
Nitrogen(N), phosphorus(P), and potassium(K) are essential macronutrients that are crucial not only for maize growth and development, but also for crop yield and quality. The genetic basis of macronutrient dynamics an... Nitrogen(N), phosphorus(P), and potassium(K) are essential macronutrients that are crucial not only for maize growth and development, but also for crop yield and quality. The genetic basis of macronutrient dynamics and accumulation during grain filling in maize remains largely unknown. In this study, we evaluated grain N, P, and K concentrations in 206 recombinant inbred lines generated from a cross of DH1M and T877 at six time points after pollination. We then calculated conditional phenotypic values at different time intervals to explore the dynamic characteristics of the N, P, and K concentrations. Abundant phenotypic variations were observed in the concentrations and net changes of these nutrients. Unconditional quantitative trait locus(QTL) mapping revealed 41 non-redundant QTLs, including 17, 16, and 14 for the N, P, and K concentrations, respectively. Conditional QTL mapping uncovered 39 non-redundant QTLs related to net changes in the N, P, and K concentrations. By combining QTL, gene expression, co-expression analysis, and comparative genomic data, we identified 44, 36, and 44 candidate genes for the N, P, and K concentrations, respectively, including GRMZM2G371058 encoding a Doftype zinc finger DNA-binding family protein, which was associated with the N concentration, and GRMZM2G113967encoding a CBL-interacting protein kinase, which was related to the K concentration. The results deepen our understanding of the genetic factors controlling N, P, and K accumulation during maize grain development and provide valuable genes for the genetic improvement of nutrient concentrations in maize. 展开更多
关键词 MAIZE nutrient concentration unconditional QTL mapping conditional QTL mapping dynamic trait
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Rheological properties and concentration evolution of thickened tailings under the coupling effect of compression and shear 被引量:1
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作者 Aixiang Wu Zhenqi Wang +3 位作者 Zhuen Ruan Raimund Bürger Shaoyong Wang Yi Mo 《International Journal of Minerals,Metallurgy and Materials》 SCIE EI CAS CSCD 2024年第5期862-876,共15页
Cemented paste backfill(CPB)is a key technology for green mining in metal mines,in which tailings thickening comprises the primary link of CPB technology.However,difficult flocculation and substandard concentrations o... Cemented paste backfill(CPB)is a key technology for green mining in metal mines,in which tailings thickening comprises the primary link of CPB technology.However,difficult flocculation and substandard concentrations of thickened tailings often occur.The rheological properties and concentration evolution in the thickened tailings remain unclear.Moreover,traditional indoor thickening experiments have yet to quantitatively characterize their rheological properties.An experiment of flocculation condition optimization based on the Box-Behnken design(BBD)was performed in the study,and the two response values were investigated:concentration and the mean weighted chord length(MWCL)of flocs.Thus,optimal flocculation conditions were obtained.In addition,the rheological properties and concentration evolution of different flocculant dosages and ultrafine tailing contents under shear,compression,and compression-shear coupling experimental conditions were tested and compared.The results show that the shear yield stress under compression and compression-shear coupling increases with the growth of compressive yield stress,while the shear yield stress increases slightly under shear.The order of shear yield stress from low to high under different thickening conditions is shear,compression,and compression-shear coupling.Under compression and compression-shear coupling,the concentration first rapidly increases with the growth of compressive yield stress and then slowly increases,while concentration increases slightly under shear.The order of concentration from low to high under different thickening conditions is shear,compression,and compression-shear coupling.Finally,the evolution mechanism of the flocs and drainage channels during the thickening of the thickened tailings under different experimental conditions was revealed. 展开更多
关键词 thickened tailings compression-shear coupling compressive yield stress shear yield stress concentration
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Application of Low Tube Voltage, Low-concentration Contrast Agent Using a 320-row CT in Coronary CT Angiography: Evaluation of Image Quality, Radiation Dose and Iodine Intake 被引量:11
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作者 Yue-ying PAN Shu-chang ZHOU +4 位作者 Yu-jin WANG Qian LI Ting-ting ZHU Chun-xia LIU Han-xiong GUAN 《Current Medical Science》 SCIE CAS 2020年第1期178-183,共6页
The effect of low voltage and low concentration contrast agent on image quality of coronary CT angiography,radiation dose and iodine intake was evaluated.A total of 121 patients with body mass index(BMI)<26 kg/m2 a... The effect of low voltage and low concentration contrast agent on image quality of coronary CT angiography,radiation dose and iodine intake was evaluated.A total of 121 patients with body mass index(BMI)<26 kg/m2 and heart rate(HR)<70 beats/min were randomly divided into four groups:group A(n=31,80 kVp,270 mgl/mL);group B(n=33,100 kVp,270 mgl/mL);group C(h=30,100 kVp,320 mgl/mL);group D(w=27,100 kVp,400 mgl/mL).The automatic current modulation system and the iterative algorithm for reconstruction were adopted in each group.The CT values and SD values of the aortic root(AR),subcutaneous fat,left coronary artery opening(LCA),and right coronary artery opening(RCA)were measured in all groups,the signalto-noise ratio(SNR)and contrast noise ratio(CNR)were calculated,and effective radiation dose and iodine intake were recorded.The subjective assessment for image quality was performed by two physicians using a 4-point scale.The results were compared using the one-way ANOVA and rank sum tests.The image quality of the four groups met the clinical diagnostic requirements.The CT values of AR in groups A,B,C,and D were 537.6±71.4,447.2±81.9,445.2±64.9 and 518.5±94.9 Hu,respectively,with no significant difference between group A and group D,or between group B and group C,while CT values in groups B and C were significantly lower than those in groups A and D(P<0.05).In groups A,B,C,and D,the LCA SNR values were 22.7±9.1,23.3±9.1,23.3±7.7 and 26.6±8.9,and the RCA CNR values were 26.9±9.&28.5±11.4,27.7土&8 and 32」±10.6,respectively.The AR visual scores in groups A,B,C and D were 3.8±0.2,3.9±0.3,3.9±0.3 and 4.0±0.3,respectively.There were no significant differences in SNR,CNR and visual score among the four groups(P>0.05).The radiation doses in groups A,B,C and D were 2.6±1.4,3.6±1.&4.9±3.5 and 4.9±2.8 mSv,respectively.The radiation dose in group A was significantly less than that in the rest three groups(P<0.05).The iodine intakes in groups A,B,C and D were 14.9±1.5,15.0±1.5,17.7±2.0 and 18.1±2.5 g,respectively.There was no significant difference in the intake of iodine between groups C and D,or between groups A and B,while iodine intake in groups A and B were significantly reduced as compared with that in groups C and D(P<0.05).It was concluded that for patients with low BMI and controlled HR,compared to 100 kVp tube voltage combined with multiple concentration contrast agents,80 kVp combined with 270 mgl/mL contrast agent is enough to ensure the quality of the images,and can reduce the radiation dose significantly,while reducing the amount of iodine intake notably,thus reducing the incidence of adverse reaction. 展开更多
关键词 tube voltage contrast agent coronary CT angiography radiation dose iodine intake
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Analysis of influencing factors on the method for determining boron concentration and dose through dual prompt gamma detection 被引量:5
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作者 Feng Tian Chang-Ran Geng +4 位作者 Xiao-Bin Tang Di-Yun Shu Huang-Feng Ye Silva Bortolussi Chun-Hui Gong 《Nuclear Science and Techniques》 SCIE EI CAS CSCD 2021年第4期10-19,共10页
A method based on the cross-sectional relationship between^(10)B(n,α)^(7)Li and^(1)H(n,γ)^(2)H was proposed to detect and reconstruct the three-dimensional boron concentration/dose distribution in vivo during boron ... A method based on the cross-sectional relationship between^(10)B(n,α)^(7)Li and^(1)H(n,γ)^(2)H was proposed to detect and reconstruct the three-dimensional boron concentration/dose distribution in vivo during boron neutron capture therapy(BNCT).Factors such as the neutron energy,fluence rate,and degree of non-uniform distribution of the boron concentration in a voxel may affect the results of this method.A theoretical analysis of the accuracy of the method using a Monte Carlo simulation shows that the determining error is generally less than 1%under different tumor locations and neutron source configurations.When the voxel size is larger than 0.4 cm,the determining error might be higher for a non-uniformly distributed boron concentration in the voxel because of the changes in the neutron energy and fluence rate.In conclusion,the proposed method enables an accurate threedimensional boron determination in vivo during BNCT. 展开更多
关键词 BNCT Boron concentration Prompt gamma Capture cross section
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Different concentrations of hyaluronic acid eye drops for dry eye syndrome: a systematic review and Meta-analysis
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作者 Xiao-Wei Ouyang Sheng Fang +5 位作者 Yun-Min Yi Shi-Peng Zou Qi-Yu Hu Zi-Xuan Huang Qing-Xia Li Jin-Yan Luo 《International Journal of Ophthalmology(English edition)》 SCIE CAS 2024年第6期1110-1119,共10页
AIM:To compare high or low concentration of hyaluronic acid eye drops(HY)for dry eye syndromes(DES).METHODS:Randomized controlled trials(RCTs)comparing various concentrations of HY were searched in PubMed,Embase,Web o... AIM:To compare high or low concentration of hyaluronic acid eye drops(HY)for dry eye syndromes(DES).METHODS:Randomized controlled trials(RCTs)comparing various concentrations of HY were searched in PubMed,Embase,Web of Science,Cochrane,SinoMed,CNKI,Wanfang Database,CQVIP,and Chinese journals databases between inception and July 2023.Pooled standardized mean differences(SMD)or weighted mean difference(WMD)with 95%confidence intervals(CI)from RCTs evaluating Schirmer’s I test(SIT),corneal fluorescein staining score(CFS),tear breakup time(TBUT),DES score(DESS),and Ocular Surface Disease Index(OSDI)were calculated.Sensitivity analysis,Egger’s test and Meta-regression analysis were performed for all indicators.RESULTS:We conducted a Meta-analysis of 10 RCTs that met the inclusion criteria,involving 1796 cases.High-concentrations group significantly improved the outcome of CFS according to random effects modelling(SMD,-3.37;95%CI,-5.25 to-1.48;P=0.0005).The rest of the results were not statistically significant,including indicators such as SIT,TBUT,DESS and OSDI.CONCLUSION:For dry eyes with positive corneal staining,a high concentration of HY is recommended,whereas in other cases,a high concentration of HY does not offer a more pronounced advantage over a low concentration of HY in the treatment of dry eyes. 展开更多
关键词 dry eye hyaluronic acid concentration META-ANALYSIS
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Achievable hole concentration at room temperature as a function of Mg concentration for MOCVD-grown p-GaN after sufficient annealing
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作者 Siyi Huang Masao Ikeda +4 位作者 Feng Zhang Minglong Zhang Jianjun Zhu Shuming Zhang Jianping Liu 《Journal of Semiconductors》 EI CAS CSCD 2024年第8期67-73,共7页
Relationship between the hole concentration at room temperature and the Mg doping concentration in p-GaN grown by MOCVD after sufficient annealing was studied in this paper.Different annealing conditions were applied ... Relationship between the hole concentration at room temperature and the Mg doping concentration in p-GaN grown by MOCVD after sufficient annealing was studied in this paper.Different annealing conditions were applied to obtain sufficient activation for p-GaN samples with different Mg doping ranges.Hole concentration,resistivity and mobility were characterized by room-temperature Hall measurements.The Mg doping concentration and the residual impurities such as H,C,O and Si were measured by secondary ion mass spectroscopy,confirming negligible compensations by the impurities.The hole concentration,resistivity and mobility data are presented as a function of Mg concentration,and are compared with literature data.The appropriate curve relating the Mg doping concentration to the hole concentration is derived using a charge neutrality equation and the ionized-acceptor-density[N-(A)^(-)](cm^(−3))dependent ionization energy of Mg acceptor was determined asE_(A)^(Mg)=184−2.66×10^(−5)×[N_(A)^(-)]1/3 meV. 展开更多
关键词 P-GAN hole concentration electrical properties ANNEALING ionization energy
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Study on the spatial and temporal evolutionary characteristics of ozone concentration and the impact of human activities in China in 2019
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作者 Yongchun Wang Wang Zhang +4 位作者 Yu’an Liu Yazhu Wang Yuting Fu Zhaohui Feng Lingqing Wang 《Acta Geochimica》 EI CAS CSCD 2024年第5期985-995,共11页
Ozone(O_(3))pollution has a profound impact on human health,vegetation development,and the ecological environment,making it a critical focus of global academic research.In recent years,O_(3)pollution in China has been... Ozone(O_(3))pollution has a profound impact on human health,vegetation development,and the ecological environment,making it a critical focus of global academic research.In recent years,O_(3)pollution in China has been on a steady rise,with ozone emerging as the sole conventional pollutant to consistently increase in concentration without any decline.This study conducted a quantitative analysis of O_(3)concentrations across 367 Chinese cities in 2019,examining spatial autocorrelation and local clustering of O_(3)levels,and investigated the diverse relationships between human activity factors and O_(3)concentration.The seasonal fluctuation of O_(3)exhibited the“M-type”pattern,with peak concentrations in winter and the lowest levels in summer.The center of O_(3)pollution migrated southeastward,with the area of highest concentration progressively shifting south along the eastern coast.Moreover,O_(3)concentration showed a strong positive correlation with population density,road freight volume,and industrial emissions,suggesting that human activities,vehicle emissions,and industrial operations are significant contributors to O_(3)production.The results provide comprehensive information on the characteristics,causes,and occurrence mechanism of O_(3)in Chinese cities that can be utilized by global government departments to formulate strategies to prevent and control O_(3)pollution. 展开更多
关键词 Ozone concentration Urban agglomerations Human activities Spatial heterogeneity
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Effects of Different Concentrations of Sulfate Ions on Carbonate Crude Oil Desorption:Experimental Analysis and Molecular Simulation
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作者 Nannan Liu Hengchen Qi +1 位作者 Hui Xu Yanfeng He 《Fluid Dynamics & Materials Processing》 EI 2024年第8期1731-1741,共11页
Low salinity water containing sulfate ions can significantly alter the surface wettability of carbonate rocks.Nevertheless,the impact of sulfate concentration on the desorption of oil film on the surface of carbonate ... Low salinity water containing sulfate ions can significantly alter the surface wettability of carbonate rocks.Nevertheless,the impact of sulfate concentration on the desorption of oil film on the surface of carbonate rock is still unknown.This study examines the variations in the wettability of the surface of carbonate rocks in solutions containing varying amounts of sodium sulfate and pure water.The problem is addressed in the framework of molecular dynamics simulation(Material Studio software)and experiments.The experiment’s findings demonstrate that sodium sulfate can increase the rate at which oil moisture is turned into water moisture.The final contact angle is smaller than that of pure water.The results of the simulations show that many water molecules travel down the water channel under the influence of several powerful forces,including the electrostatic force,the van der Waals force and hydrogen bond,crowding out the oil molecules on the calcite’s surface and causing the oil film to separate.The relative concentration curve of water and oil molecules indicates that the separation rate of the oil film on the surface of calcite increases with the number of sulfate ions. 展开更多
关键词 Carbonate rocks WETTABILITY sulfate ions concentration molecular simulation DESORPTION
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Study on concentration distribution and detonation characteristics for non-axisymmetric fuel dispersal
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作者 Linghui Zeng Zhongqi Wang +1 位作者 Xing Chen Jianping Li 《Defence Technology(防务技术)》 SCIE EI CAS CSCD 2024年第1期484-495,共12页
The study of non-axisymmetric fuel dispersal and detonation can provide reference for the prevention of industrial cloud explosion accidents and the design of fuel air explosive(FAE).The concentration and detonation f... The study of non-axisymmetric fuel dispersal and detonation can provide reference for the prevention of industrial cloud explosion accidents and the design of fuel air explosive(FAE).The concentration and detonation fields of 85 kg cylindrical and fan-shaped fuel are investigated by experiments and numerical simulations.A dynamic model of the whole process for fuel dispersal and detonation is built.The concentration distribution of fuel is used as the initial condition to calculate the detonation stage,thus solving the initial value problem of detonation field.The phase and component changes of fuel cloud at different locations are compared.The fuel cloud is divided into directions of 0°,90°,135°and 180°.The results show that the maximum cloud radius is 20.94 m in 135°and the minimum is 12.04 m in 0°.The diameter of the detonation fireball is 53.6 m,and the peak temperature is 3455 K.The highest peak overpressure is 3.44 MPa in 0°and the lowest is 2.97 MPa in 135°.The proportion of liquid phase in 0°is22.90%,and the fuel loss is 11.8% and 9% higher than that in 135°and cylindrical charge,respectively.The stable propagation distance of blast wave in 135°is 42.50% longer than 0°and 28.37% longer than cylindrical charge. 展开更多
关键词 Fuel dispersal concentration distribution Detonation characteristic Fuel loss Numerical simulation
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Effects of Serum Concentration, Synchronization Time and Confluence on the Cell-Cycle Synchronization Efficiency of Goat Fibroblasts
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作者 Van Khanh Nguyen Huong Thu Thi Vu +4 位作者 Au Thi Hoang Yen Kim Thi Pham Giang Thi Thanh Nhan Hung Phu Lai Lan Doan Pham 《Open Journal of Animal Sciences》 2024年第3期194-203,共10页
This study aims to evaluate the effect of serum concentration, synchronization time, and confluence degree on the synchronisation efficiency of goat fibroblast cycle. The results indicated that there was no difference... This study aims to evaluate the effect of serum concentration, synchronization time, and confluence degree on the synchronisation efficiency of goat fibroblast cycle. The results indicated that there was no difference in the percentage of nucleated fibroblasts in the G0/G1 stage between serum concentrations of 0.3% and 0.4% (83.89% and 82.69%, respectively, P > 0.05) as well as between serum concentrations of 0.2% and 0.5% (76.95% and 75.46%, respectively, P > 0.05). The percentage of nucleated fibroblasts in the G0/G1 stage was highest at the concentration of 0.3% and lowest in the control group (83.89% vs. 62.67%, P 0.05). The beneficial effect of high confluence was confirmed by the large percentage of nucleated fibroblasts at the G0/G1 stage. The 60% confluency was significantly lower than the 80% and 100% confluency (73.44%, 86.63%, and 87.17%, respectively, P < 0.05). The results indicate that the goat fibroblast cycle synchronization is the most effective at the serum concentration of 0.3%, 72 hours of synchronization and 100% confluency. 展开更多
关键词 Goat Fibroblast Cycle Synchronisation Serum concentration Synchronization Time CONFLUENCE
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Effects of different concentrations of nicotinamide on hematopoietic stem cells cultured in vitro
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作者 Yan Ren Yan-Ni Cui Hong-Wei Wang 《World Journal of Stem Cells》 SCIE 2024年第2期163-175,共13页
BACKGROUND In vitro expansion to increase numbers of hematopoietic stem cells(HSCs)in cord blood could improve clinical efficacy of this vital resource.Nicotinamide(NAM)can promote HSC expansion ex vivo,but its effect... BACKGROUND In vitro expansion to increase numbers of hematopoietic stem cells(HSCs)in cord blood could improve clinical efficacy of this vital resource.Nicotinamide(NAM)can promote HSC expansion ex vivo,but its effect on hematopoietic stem and progenitor cells(HSPCs,CD34^(+)CD38)and functional subtypes of HSCs-shortterm repopulating HSCs(ST-HSCs,CD34^(+)CD38CD45RACD49f^(+))and long-term repopulating HSCs(LT-HSCs,CD34^(+)CD38CD45RACD49f^(+)CD90^(+))is not yet known.As a sirtuin 1(SIRT1)inhibitor,NAM participates in regulating cell adhesion,polarity,migration,proliferation,and differentiation.However,SIRT1 exhibits dual effects by promoting or inhibiting differentiation in different tissues or cells.We propose that the concentration of NAM may influence proliferation,differentiation,and SIRT1 signaling of HSCs.AIM To evaluate the effects and underlying mechanisms of action of different concentrations of NAM on HSC proliferation and differentiation.METHODS CD34^(+)cells were purified from umbilical cord blood using MacsCD34 beads,and cultured for 10-12 d in a serum-free medium supplemented with cytokines,with different concentrations of NAM added according to experimental requirements.Flow cytometry was used to detect phenotype,cell cycle distribution,and apoptosis of the cultured cells.Real-time polymerase chain reaction was used to detect the transcription levels of target genes encoding stemness-related factors,che mokines,components of hypoxia pathways,and antioxidant enzymes.Dichloro-dihydro-fluorescein diacetate probes were used to evaluate intracellular production of reactive oxygen species(ROS).Determination of the effect of different culture conditions on the balance of cytokine by cytometric bead array.RESULTS Compared with the control group,the proportion and expansion folds of HSPCs(CD34^(+)CD38)incubated with 5 mmol/L or 10 mmol/L NAM were significantly increased(all P<0.05).The ST-HSCs ratio and fold expansion of the 5 mmol/L NAM group were significantly higher than those of the control and 10 mmol/L NAM groups(all P<0.001),whereas the LT-HSCs ratio and fold expansion of the 10 mmol/L NAM group were significantly higher than those of the other two groups(all P<0.05).When the NAM concentration was>10 mmol/L,cell viability significantly decreased.In addition,compared with the 5 mmol/L NAM group,the proportion of apoptotic cells in the 10 mmol/L NAM group increased and the proportion of cells in S and G2 phase decreased.Compared with the 5 mmol/L NAM group,the HSCs incubated with 10 mmol/L NAM exhibited significantly inhibited SIRT1 expression,increased intracellular ROS content,and downregulated expression of genes encoding antioxidant enzymes(superoxide dismutase 1,peroxiredoxin 1).CONCLUSION Low concentrations(5 mmol/L)of NAM can better regulate the balance between proliferation and differentiation,thereby promoting expansion of HSCs.These findings allow adjustment of NAM concentrations according to expansion needs. 展开更多
关键词 Hematopoietic stem cells NICOTINAMIDE concentration PROLIFERATION DIFFERENTIATION Sirtuin 1
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A Facile Li_(2)TiO_(3) Surface Modification to Improve the Structure Stability and Electrochemical Performance of Full Concentration Gradient Li-Rich Oxides
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作者 Naifang Hu Yuan Yang +5 位作者 Lin Li Yuhan Zhang Zhiwei Hu Lan Zhang Jun Ma Guanglei Cui 《Energy & Environmental Materials》 SCIE EI CAS CSCD 2024年第3期41-48,共8页
Full concentration gradient lithium-rich layered oxides are catching lots of interest as the next generation cathode for lithium-ion batteries due to their high discharge voltage,reduced voltage decay and enhanced rat... Full concentration gradient lithium-rich layered oxides are catching lots of interest as the next generation cathode for lithium-ion batteries due to their high discharge voltage,reduced voltage decay and enhanced rate performance,whereas the high lithium residues on its surface impairs the structure stability and long-term cycle performance.Herein,a facile multifunctional surface modification method is implemented to eliminate surface lithium residues of full concentration gradient lithium-rich layered oxides by a wet chemistry reaction with tetrabutyl titanate and the post-annealing process.It realizes not only a stable Li_(2)TiO_(3)coating layer with 3D diffusion channels for fast Li^(+)ions transfer,but also dopes partial Ti^(4+)ions into the sub-surface region of full concentration gradient lithium-rich layered oxides to further strengthen its crystal structure.Consequently,the modified full concentration gradient lithium-rich layered oxides exhibit improved structure stability,elevated thermal stability with decomposition temperature from 289.57℃to 321.72℃,and enhanced cycle performance(205.1 mAh g^(-1)after 150 cycles)with slowed voltage drop(1.67 mV per cycle).This work proposes a facile and integrated modification method to enhance the comprehensive performance of full concentration gradient lithium-rich layered oxides,which can facilitate its practical application for developing higher energy density lithium-ion batteries. 展开更多
关键词 full concentration gradient lithium-rich layered oxides structure stability surface modification
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Experimental Study on the Chloride Ion Concentration of Cement Pastes Prepared with Limestone Powder
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作者 ZHANG Kaijian HUANG Zeping +1 位作者 JIA Xuxiu WANG Dehui 《Journal of Wuhan University of Technology(Materials Science)》 SCIE EI CAS CSCD 2024年第6期1474-1483,共10页
To investigate the impact of limestone powder on the chloride ion concentration coefficient of cement pastes,various techniques such as scanning electron microscopy(SEM),X-ray diffraction(XRD),thermogravimetric analys... To investigate the impact of limestone powder on the chloride ion concentration coefficient of cement pastes,various techniques such as scanning electron microscopy(SEM),X-ray diffraction(XRD),thermogravimetric analysis(TGA),and mercury-porosimetry(MIP)were employed in this paper.The findings demonstrate that the creation of Friedel's salt is inversely associated with the addition of limestone powder,that is,Friedel's salt production is lessened by adding more limestone powder,however,the coefficient of chloride ion concentration initially decreased and then increased again,as does the porosity,and most likely the pore size as well.The specific surface area of limestone powder has increased,and the content of Friedel’s salt increased first and then decreased.However,the shifting trend of Friedel's salt and chloride ion concentration coefficient is in direct opposition,and the pore structure was therefore significantly enhanced.The results of this study offer robust theoretical backing for the inclusion of limestone powder in concrete and provide a positive assessment of its potential applications. 展开更多
关键词 limestone powder specific surface area CONTENT friedel's salt chloride ion concentration coefficient
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Global CO_(2) concentration change induced by“trigger-connectors”model,especially since about 24 Ma?A preliminary hypothesis
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作者 LI Leyi CHANG Hong 《地球环境学报》 CSCD 2024年第4期545-565,共21页
Background,aim,and scope The tectonic uplift of the Cenozoic Tibetan Plateau has produced a chain effect,which is an excellent location for Earth system science research,and its uplift process,mechanism and environmen... Background,aim,and scope The tectonic uplift of the Cenozoic Tibetan Plateau has produced a chain effect,which is an excellent location for Earth system science research,and its uplift process,mechanism and environmental effects are the hot spot and frontier of the current research.The“Tibetan Plateau uplift-weathering-CO_(2) concentration-global climate change”model was put forward by Raymo and Ruddiman to interpret the Late Cenozoic climate change.However,there are still some questions suspended,such as does the weathering of the Tibetan Plateau have the ability to control the global climate?How to explain the modern-like global CO_(2) concentration starting at about 24 Ma?Here,a short space was taken to present a brainstorm about the above questions on account of existing geological pieces of evidence.Materials and methods In this paper,we integrate the formation and evolution of the Yangtze River and Pearl River,the origin and development of the Asian inland aridification-monsoon system,the Cenozoic tectonic uplift process of the Tibetan Plateau,and the westerly winds to discuss and analyze the relationship between the Cenozoic CO_(2) concentration changes and the uplift of the Tibetan Plateau and why the CO_(2) concentration similar to the present was formed at about 24 Ma.Results Similar correspondence of the surface uplift history of Xizang,other global mountains,and the declining CO_(2) concentration could support the theory Tibetan Plateau weathering inf luences CO_(2) concentration.Starting from 24 Ma,the most important character was the uplift and erosion of Xizang and Himalaya,collaborating with Ocean Iron Fertilization(OIF)together as an entity to control the atmospheric CO_(2) concentration because the great Asian rivers,Asian monsoons,and westerlies connected Xizang and surrounded seas together through materials transportation.Discussion Paleogeographic reconstructions from 40 Ma to 20 Ma illustrate that the main topographic change occurred in the Andes,Cordillera orogenic belt,and Xizang.We comprise a comprehensive set of evidence from independent data,which correspond temporally with the tipping point(about 24 Ma)of the atmospheric CO_(2) and we noticed that modern-like Asia monsoon,inland aridity,Asian great rivers,and climate zone formed at about 24 Ma and also there are tectonic activities for the Andes and Rockies.We raised the possibility that the modern-like atmospheric CO_(2) concentration at about 24 Ma was caused by the above geological factors.Here the rivers,monsoon,and westerlies are termed as“connectors”.In addition,these Asian rivers originated from Xizang,the monsoon,and inner Asian aridification are strongly a function of the uplift and growth of Xizang,thus,Xizang here is named as“trigger”.The distinct character of“trigger-connectors”model is that this not only takes the monsoon,westerlies,and the global great rivers into consideration but also expands the range which inf luences atmospheric CO_(2) concentration,from local points to a vast area since about 24 Ma,such as from Tibetan Plateau to Asia,including surrounded seas,after about 24 Ma.However,because the opening of the Late Oligocene-Early Miocene Antarctic periphery straits is highly coincident with the onset of modern-like global atmospheric CO_(2) concentration,we are forced to consider that they also had a significant impact on the reduction of atmospheric CO_(2) concentrations at this time.Conclusions“Trigger-connectors”was put forward to explain the Cenozoic CO_(2) variation,especially modern-like global CO_(2) concentration since about 24 Ma.Recommendations and perspectives Here we use the“trigger-connectors”model to explain the formation of modern-like CO_(2) concentrations starting at about 24 Ma,but there are still some problems.The most important premise for the“trigger-connectors”model is the constructed Cenozoic CO_(2) concentration record is reliable,which is the foundation of our hypothesis.In the future,potential improvements should focus on topographic reconstructions of Xizang and the global mountains.Here we have concentrated on Xizang in the considered timeslices but still,pay less attention to other global orogenic belts.Collaborations with geologist experts in those regions could provide valuable feedback to evaluate their potential role of them in CO_(2) evolution.What is more,considerable progress may be achieved with the addition and consideration of more and new geological data. 展开更多
关键词 Tibetan Plateau CO_(2) concentration WEATHERING trigger-connectors
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Effect of low concentration electrolytes on the formation and corrosion resistance of PEO coatings on AM50 magnesium alloy
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作者 Peng Xie Carsten Blawert +4 位作者 Maria Serdechnova Natalia Konchakova Tatsiana Shulha Ting Wu Mikhail L.Zheludkevich 《Journal of Magnesium and Alloys》 SCIE EI CAS CSCD 2024年第4期1386-1405,共20页
In this paper,the formation process,morphology,and electrochemical performance of PEO coatings on AM50 magnesium alloy prepared in low concentration phosphate,aluminate,and phosphate-aluminate electrolytes were system... In this paper,the formation process,morphology,and electrochemical performance of PEO coatings on AM50 magnesium alloy prepared in low concentration phosphate,aluminate,and phosphate-aluminate electrolytes were systematically studied.The results show that the coatings prepared from the phosphate electrolytes have a higher thickness and better corrosion resistance properties compared to the other electrolytes.The coatings prepared from low concentration phosphate-aluminate mixed electrolytes have slightly thinner thickness,a similar coating structure and an order of magnitude lower value of electrochemical impedance compared with phosphate electrolyte coatings.The Coatings prepared from low concentration aluminate electrolytes have the lowest thickness and the worst corrosion resistance properties which gets close to corrosion behavior of the bare AM50 under the same test conditions.Considering application,coatings prepared from single low concentration phosphate electrolytes and low concentration phosphate-aluminate electrolytes have greater potential than single low concentration aluminate coatings.However,reducing the electrolyte concentrations of coating forming ions too much has negative influence on the coating growth rate. 展开更多
关键词 Plasma electrolytic oxidation Low concentration electrolytes Corrosion resistance AM50 magnesium alloy
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Measurement of Radon Concentration and Estimation of Cancer Risk in Twenty-Four Model Houses in the Town of Koudougou
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作者 Moumouni Derra Luc Telado Bambara +3 位作者 Karim Kaboré Yalgado Zakaria Sawadogo Ousmane Cissé François Zougmoré 《Open Journal of Applied Sciences》 2024年第1期193-204,共12页
The objective of our study is to evaluate the concentration of radon (<sup>86</sup>Rn) inside houses in the town of Koudougou in order to estimate its impact on the health of the population. Indeed, when u... The objective of our study is to evaluate the concentration of radon (<sup>86</sup>Rn) inside houses in the town of Koudougou in order to estimate its impact on the health of the population. Indeed, when uranium-rich minerals are found near the surface of the ground, radon concentrations can reach tens of becquerels per cubic meter in enclosed spaces. Given the nature of the geological base of Burkina Faso, this situation is quite probable and certain places that are sometimes poorly ventilated (house, school, office, etc.) can have radon levels high enough to constitute a health problem for occupants. Thus, twenty-four (24) sample houses were identified. In each house, the Corentium digital detector was between 0.8 m and 2 m for at least one week in a place where the occupants estimate that they spend more time of time and measure the concentration of radon in the long term and short term. The recorded data allowed us to determine the Absorbed Dose and the Annual Effective Dose of radon gas for each house in order to estimate the Risk of Cancer and the probable Number of Cases of Lung Cancer per million inhabitants. Thus, the results indicate that the long-term radon concentration varies between 6 Bq/m<sup>3</sup> and 285 Bq/m<sup>3</sup> respectively in houses 11 and 4 compared to 1 Bq/m<sup>3</sup> to 208 Bq/m<sup>3</sup> in the short term in the same houses. Also, in the long term, in control houses 1, 3 and 4, the radon level is above the recommended threshold interval. For the short term, these are houses 1, 3, 4 and 17 respectively with 110 Bq/m<sup>3</sup>, 142 Bq/m<sup>3</sup>, 208 Bq/m<sup>3</sup> and 105 Bq/m<sup>3</sup>. As for the long-term and short-term effective doses, only houses 1, 3, 4, 17 and 24 have values between 3 - 10 Sv/year. The estimation of the relative risk of lung cancer gives values relatively close to unity and between 1.006 and 1.142 with an average of 1.035 and that of the Number of Lung Cancer Cases per million inhabitants gives values between 8 and 166 with an average of 42. Thus, we can conclude that with the exception of houses 1, 3, 4 and 17, the radon concentrations are relatively low in the twenty-four control houses in the city of Koudougou. The lifestyle of the populations can well explain this situation when we know that people are in the habit of always leaving doors and windows open, especially when they are not sleeping. We can therefore say that the risk of population exposure to radon gas is relatively low in the town of Koudougou. 展开更多
关键词 RADON Absorbed dose Annual Effective dose Cancer Risk
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A multi-scale second-order autoregressive recursive filter approach for the sea ice concentration analysis
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作者 Lu Yang Xuefeng Zhang 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2024年第3期115-126,共12页
To effectively extract multi-scale information from observation data and improve computational efficiency,a multi-scale second-order autoregressive recursive filter(MSRF)method is designed.The second-order autoregress... To effectively extract multi-scale information from observation data and improve computational efficiency,a multi-scale second-order autoregressive recursive filter(MSRF)method is designed.The second-order autoregressive filter used in this study has been attempted to replace the traditional first-order recursive filter used in spatial multi-scale recursive filter(SMRF)method.The experimental results indicate that the MSRF scheme successfully extracts various scale information resolved by observations.Moreover,compared with the SMRF scheme,the MSRF scheme improves computational accuracy and efficiency to some extent.The MSRF scheme can not only propagate to a longer distance without the attenuation of innovation,but also reduce the mean absolute deviation between the reconstructed sea ice concentration results and observations reduced by about 3.2%compared to the SMRF scheme.On the other hand,compared with traditional first-order recursive filters using in the SMRF scheme that multiple filters are executed,the MSRF scheme only needs to perform two filter processes in one iteration,greatly improving filtering efficiency.In the two-dimensional experiment of sea ice concentration,the calculation time of the MSRF scheme is only 1/7 of that of SMRF scheme.This means that the MSRF scheme can achieve better performance with less computational cost,which is of great significance for further application in real-time ocean or sea ice data assimilation systems in the future. 展开更多
关键词 second-order auto-regressive filter multi-scale recursive filter sea ice concentration three-dimensional variational data assimilation
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Relationship between plasma risperidone concentrations and clinical features in chronic schizophrenic patients in China
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作者 Jing-Wen Xu Xiao-Bo Guan +4 位作者 Xue-Ying Wang Yang Feng Qi Zhang Jun-Juan Zhu Jian-Hua Chen 《World Journal of Psychiatry》 SCIE 2024年第4期523-532,共10页
BACKGROUND Prior studies have noted great variability in the plasma levels of risperidone(RIS).Plasma concentrations of RIS and its active moiety are highly variable and depend on absorption,metabolism,and other predi... BACKGROUND Prior studies have noted great variability in the plasma levels of risperidone(RIS).Plasma concentrations of RIS and its active moiety are highly variable and depend on absorption,metabolism,and other predictors of metabolic dysregulation;however,these factors are poorly understood and the association between metabolic change and change in psychopathology is uncertain.AIM To ascertain the characteristics of chronic schizophrenic patients treated with RIS,and to assess their relationship with plasma RIS levels.METHODS This was a descriptive cross-sectional study of 50 patients with a diagnosis of schizophrenic psychosis treated with RIS in a psychiatric service.The plasma concentrations of RIS and its metabolite 9-hydroxyrisperidone were determined by high performance liquid chromatography.The patients’demographic and clinical characteristics,and psychopathologies were assessed,and the associations between clinical variables and plasma levels of RIS were explored.RESULTS Male patients received higher doses of RIS than female ones,but plasma concentrations of RIS and risperidone+9-hydroxyrisperidone(active moiety)were higher in female patients.Age and the mean scores of the general psychopathology subscale of the Positive and Negative Syndrome Scale(PANSS)were significantly positively correlated with plasma concentrations of risperidone+9-hydroxyrisperidone adjusted for weight and dose in all 50 subjects.In male subjects,we found a statistically significant positive correlation between the concentrations of risperidone+9-hydroxyrisperidone in plasma/(dose×kg)and age,mean PANSS negative subscale scores,mean PANSS general psychopathology subscale scores,and mean PANSS total scores.CONCLUSION Long-term use of RIS should be closely monitored in older patients and females to minimize the risk of high concentrations which could induce side effects. 展开更多
关键词 ANTIPSYCHOTICS RISPERIDONE 9-HYDROXYRISPERIDONE Plasma drug concentration monitoring Chronic schizophrenia
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Efficient concentration of trace analyte with ordered hotspot construction for a robust and sensitive SERS platform
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作者 Youdi Hu Yanlei Hu +4 位作者 Zhenyu Wang Jiale Yong Wei Xiong Dong Wu Shixiang Xu 《International Journal of Extreme Manufacturing》 SCIE EI CAS CSCD 2024年第3期532-542,共11页
Surface-enhanced Raman scattering(SERS)platform,which enables trace analyte detection,has important application prospects.By structuring/modifying the surface of the SERSsubstrate,analyte in highly diluted solutions c... Surface-enhanced Raman scattering(SERS)platform,which enables trace analyte detection,has important application prospects.By structuring/modifying the surface of the SERSsubstrate,analyte in highly diluted solutions can be concentrated into localized active areas for highly sensitive detection.However,subject to the difficulty of the fabrication process,itremains challenging to balance hot-spot construction and the concentration capacity of analyte simultaneously.Therefore,preparing SERS substrates with densely ordered hot spots andefficient concentration capacity is of great significance for highly sensitive detection.Herein,we propose an Ag and fluoroalkyl-modified hierarchical armour substrate(Ag/F-HA),which has a double-layer stacking design to combine analyte concentration with hotspot construction.The microarmour structure is fabricated by femtosecond-laser processing to serve as asuperhydrophobic and low-adhesive surface to concentrate analyte,while the anodic aluminium oxide(AAO)template creates a nanopillar array serving as dense and ordered hot spots.Under the synergistic action of hot spots and analyte concentration,Ag/F-HA achieves a detectionlimit down to 10^(-7)M doxorubicin(DOX)molecules with a RSD of 7.69%.Additionally,Ag/F-HA exhibits excellent robustness to resist external disturbances such as liquid splash or abrasion.Based on our strategy,SERS substrates with directional analyte concentrations are further explored by patterning microcone arrays with defects.This work opens a way to the realistic implementation of SERS in diverse scenarios. 展开更多
关键词 surface-enhanced Raman scattering anodic aluminium oxide femtosecond laser processing concentration of trace analytes mechanical robustness
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Determination Uranium Concentrations and Effective Dose of Drinking Water for Nineveh Governorate—Iraq, Using Kinetic Phosphorescence Analyzer (KPA)
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作者 Shafik Shakier Shafik Bushra Ali Ahmed Mazin Mohammed 《Journal of Environmental Protection》 2014年第3期200-206,共7页
In this work, the concentrations of natural Uranium and the annual effective dose (ET in Sv·y-1) in drinking water for Nineveh Governorate in northern Iraq were determined using a pulsed-laser Kinetic Phosphoresc... In this work, the concentrations of natural Uranium and the annual effective dose (ET in Sv·y-1) in drinking water for Nineveh Governorate in northern Iraq were determined using a pulsed-laser Kinetic Phosphorescence Analyzer (KPA). Furthermore, the relationship between pH for water samples and the concentration of Uranium was studied. The drinking water samples are taken approximately from all regions of Nineveh as;15 samples of tap water are taken from refinery stations, 13 samples of water samples are taken from wells that are used for drinking, and 18 samples of drinking water are withdrawn from wells in Adayyah region (this region is located near nuclear wastes site). Thus, the total studied samples are 46. The results of Uranium concentration for all samples ranged from 2.61 ± 0.08 to 9.14 ± 0.012 μg·L-1 with an overall average value about 5.87 ± 0.046 μg·L-1, and the total annual effective dose ranged from 2.3 to 8.04 μSv·y-1. The results also showed that the pH number increases with increasing Uranium concentration and have, in general, high values in well water. 展开更多
关键词 URANIUM KPA DRINKING Water INTAKE Annual Effective dose Nineveh
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