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Comprehensive study on the spatial distribution of heavy metals and their environmental risks in high-sulfur coal gangue dumps in China

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Journal of Environmental Sciences 2024年第2期136卷 486-497页

作者： Yingbo Dong huan Lu Hai lin School of Energy and Environmental Engineering University of Science and Technology BeijingBeijing 100083China Beijing Key Laboratory on Resource-oriented Treatment of Industrial Pollutants Beijing 100083China

The accumulation of coal gangue(CG)from coal mining is an important source of heavy metals(HMs)in *** spatial distribution and environment risk assessment are extremely important for the management and remediation of *** soil samples were collected from the high-sulfur CG site in northern China and analyzed for six *** results showed that the soil was heavily contaminated by Mn,Cr and Ni based on the Nemerow index,and posed seriously ecological risk depended on the geo-accumulation index,potential ecological risk index and risk assessment *** semi-variogram model and ordinary kriging interpolation accurately portrayed the spatial distribution of ***,Mn,and Cr were distributed by band diffusion,Ni was distributed by core,the distribution of Cu had obvious patchiness and Zn was more *** spatial autocorrelation indicated that all HMs had strong spatial *** BCR sequential extraction was employed to qualify the geochemical fractions of *** data indicated that Fe and Cr were dominated by residual fraction;Cu,Ni and Zn were dominated by reducible and oxidizable fractions;Mn was dominated by reducible and acid-extractable(25.38%-44.67%)*** correlation analysis showed that pH was the main control factor affecting the non-residue fractions of ***,acid production from high sulfur CG reduced soil pH by 2-3,which indirectly promoted the activity of ***,the conceptual model of HMs contamination at the CG site was proposed,which can be useful for the development of ecological remediation strategies.

关键词： High-sulfur coal gangue Soil contamination Heavy metals Spatial distribution Geochemical fractions Risk assessment

Investigation of wake-induced vibration interference between two staggered wave-cone cylinders at subcritical Reynolds number

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Journal of Hydrodynamics 2024年第2期36卷 378-393页

作者： lin Zou Di-wei Liu Jian Liu hong-cheng Zuo Yin-huan Zheng Hao Xia School of Mechanical and Electronic Engineering Wuhan University of TechnologyWuhan430070China Department of Aeronautical and Automotive Engineering Loughborough UniversityLoughboroughUK

The wake induced vibration(WIV)of a one-and two-degree-of-freedom(1DOF,2DOF)downstream wave-cone cylinder(WCC)behind a stationary equal-size upstream wave-cone cylinder in the staggered arrangement is numerically investigated at subcritical Reynolds number of 3900 by using shear stressed transfer(SST)k-ωturbulence *** streamwise pitch ratios(P/Dm)vary from 4 to 6 with a fixed incident angleα=8°.Experimental measurements were also performed for the validation of the present numerical *** is found that the largest vibration amplitude in crossflow direction occurred at P/Dm=4,Ur=8 with small difference of streamwise vibration at P/Dm=4,*** from single wavy-cone cylinder(SWCC),the downstream flexible one of a pair staggered WCCs got larger vibration amplitude during phase switching stage instead of in-phase *** upstream wake will suppress the triple frequency of main frequency in the power spectra density(PSD)functions of Cl but stimulate the double one of *** intriguing vibration mechanism happened in all 2DOF cases where the trajectory of downstream WCC is a significant ellipse rather than a figure of *** transformation of phase switching and the variation of the main frequency of drag coefficient(Cd)can be explained by the vortex-shedding modes of downstream WCC.

关键词： Two wave-cone cylinders staggered arrangement wake induced vibration phase switching vortex shedding

Possible Role of Cellular Polyamine Metabolism in Neuronal Apoptosis

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Current Medical Science 2024年第2期44卷 281-290页

作者： Xin-tong JI Wen-lei YU Meng-jia JIN lin-jie LU hong-ping YIN huan-huan WANG School of Basic Medical Sciences Affiliated Hospital of Hangzhou Normal UniversityHangzhou Normal UniversityHangzhou 311121China School of Medicine Chongqing UniversityChongqing 400030China Department of Stomatology Huzhou Wuxing District People's HospitalHuzhou Wuxing District Maternal and Child Health HospitalHuzhou 313008China School of Pharmacy Zhejiang UniversityHangzhou 310030China Department of Stomatology Haining Hospital of Traditional Chinese MedicineJiaxing 314400China

Recent studies have shown that cellular levels of polyamines(PAs)are significantly altered in neurodegenerative *** from in vivo animal and in vitro cell experiments suggests that the cellular levels of various PAs may play important roles in the central nervous system through the regulation of oxidative stress,mitochondrial metabolism,cellular immunity,and ion channel *** of PA metabolism related enzymes also contributes to neuronal injury and cognitive impairment in many neurodegenerative ***,in the current work,evidence was collected to determine the possible associations between cellular levels of PAs,and related enzymes and the development of several neurodegenerative diseases,which could provide a new idea for the treatment of neurodegenerative diseases in the future.

关键词： polyamine apoptosis mitochondria neurodegenerative disease

Selective N-Methylation of N-Methylaniline with CO_(2) and H_(2) over Cu/In_(2)O_(3) Catalyst

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Chinese Journal of Chemistry 2024年第3期42卷 276-282页

作者： huan Zheng Bo Qian lin He State Key Laboratory for Oxo Synthesis and Selective Oxidation Lanzhou Institute of Chemical PhysicsChinese Academy of SciencesLanzhouGansu730000 China University of Chinese Academy of Sciences Beijing100049 China

N-Methylation of amines with CO_(2) and H2 is a potential approach for CO_(2) utilization because N-methylated amines can be used as solvents and organic intermediates. In_(2)O_(3)-supported Cu (Cu/In_(2)O_(3)) acts as an effective heterogeneous catalyst for N-methylation reaction of N-methylaniline (MA) with CO_(2) and H_(2),showing higher N,N-dimethylaniline (DMA) selectivity than other supported Cu catalysts. On one hand,the dispersion of Cu can be improved by the defective In_(2)O_(3) support. On the other hand,In_(2)O_(3) support is active in the dissociative adsorption of CO_(2) through C—O bond breaking. In addition,the H_(2) dissociation ability of In_(2)O_(3) can also be enhanced by Cu. The combination of Cu and In_(2)O_(3) is effective in the activation of CO_(2),the adsorption of intermediate N-methylformanilide (MFA),the hydrogenation of MFA to DMA and the prohibition of C—N bond cleavage side reactions,thereby enhancing the reaction rate of MA conversion and the selectivity to DMA.

关键词： N-Methylation CO_(2) Cu/In_(2)O_(3) Supported catalysts Heterogeneous catalysis

Microstructure and Mechanical Behavior of Mg-Based Bimetal Plates with High Formability Sleeve by Co-extrusion

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Acta Metallurgica Sinica(English Letters) 2024年第3期37卷 499-512页

作者： Yue-Hui Dang Sheng-lin Liu Xiao-Lei Ai Xiao-Wei Feng Bo Feng Zhuo Tian Ying-Fei lin huan-Tao Chen Kai-hong Zheng School of Materials Science and Engineering Chang’an UniversityShaanxi 710064China Guangdong Key Laboratory of Metal Toughening Technology and Application Institute of New MaterialsGuangdong Academy of SciencesGuangzhou 510650China

In this study,microstructure and mechanical behavior of two types of Mg-based bimetal plates with a high formability sleeve were systematically studied,with a great emphasis on the effect of the interface characteristic and the sleeve fraction on the plasticity of composite *** rule of mixtures(ROM)for elongation was also *** results show that when there is no or thin diffusion layer with thickness of about 3μm,Mg-based bimetal plates have a good plasticity with elongation of about 19-24%,and the ROM predicted elongations are very close to the experimental *** contrast,with a diffusion layer about 95-155μm thick,Mg-based bimetal plates exhibit a poor plasticity with elongation of about 11-17%,and the experimental elongations largely deviate from the ROM *** plasticity of Mg-based bimetal plates increases with increasing sleeve *** study provides new insights on the plastic deformation of Mg-based bimetal composites with a high formability sleeve.

关键词： Mg-based composites Co-extrusion Microstructure Mechanical behavior Plastic deformation

Suppression Impact of Group-Velocity Dispersion on the Cell of Pulse Cleaning

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Chinese Physics Letters 2011年第4期28卷 97-100页

作者： LI Jing DENG Ying WANG Jian-Jun LI Ming-Zhong XU Dang-Peng lin hong-huan ZHU Na WANG Rui JING Feng Research Center of Laser Fusion China Academy of Engineering PhysicsPO Box 919-988Mianyang 621900

In order to improve the signal-to-noise ratio of an all-fiber front-end system for high-energy pete-watt(PW)laser devices,we propose a method to restrain the noise by optical Kerr *** terms of analytical calculation,it is found that the signal-to-noise ratio can be increased by three orders of magnitude with the cell of pulse cleaning for the pulses,with the full width at half maximum TFWHM larger than ***,numerical calculation indicates that the group-velocity dispersion(GVD)may have a marked effect on the pulses with TFWHM smaller than 100 ps but larger than 5ps,with the help of self-phase modulation(SPM).This would debase the performance of the cell of pulse ***,we study the methods of restraining the distortion for the pulses with different peak powers to improve the performance of an all-fiber front-end system for high-energy PW laser devices,These results are of benefit to the experiments and the improvement of signal-to-noise ratio for high-energy PW laser devices.

关键词： fiber restrain noise

Analysis of metabolic characteristics of metabolic syndrome in elderly patients with gastric cancer by non-targeted metabolomics

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World Journal of Gastrointestinal Oncology 2024年第6期16卷 2419-2428页

作者： huan Zhang Wen-Bing Shen lin Chen Medical School of Chinese PLA Chinese PLA General HospitalBeijing 100853China Department of Gastrointestinal Surgery Shanghai Sixth People’s HospitalShanghai 250063China Department of General Surgery The First Medical Center of Chinese PLA General HospitalBeijing 100853China

BACKGROUND The relationship between metabolic syndrome(MetS)and gastric cancer(GC),which is a common metabolic disease,has attracted much ***,the specific metabolic characteristics of MetS in elderly patients with GC remain *** To investigate the differentially abundant metabolites and metabolic pathways between preoperative frailty and MetS in elderly patients with GC based on nontargeted metabolomics *** In this study,125 patients with nonfrail nonmeal GC were selected as the control group,and 50 patients with GC in the frail group were selected as the frail ***-five patients with GC combined with MetS alone were included in the MetS group,and 50 patients with GC combined with MetS were included in the MetS *** metabolomics techniques were used to measure plasma metabolite levels by ultrahigh-performance liquid chromatography-mass *** statistical analysis was performed by principal component analysis,orthogonal partial least squares,pattern recognition analysis,cluster analysis,and metabolic pathway *** A total of 125 different metabolites,including amino acids,glycerophospholipids,sphingolipids,fatty acids,sugars,nucleosides and nucleotides,and acidic compounds,were identified via nontargeted metabolomics *** with those in the control group,there were 41,32,and 52 different metabolites in the MetS group,the debilitated group,and the combined group,*** metabolites were significantly increased in the MetS *** the weak group,amino acids and most glycerol phospholipid metabolites decreased significantly,and fatty acids and sphingosine increased *** combined group was characterized by significantly increased levels of nucleotide metabolites and acidic *** alanine,aspartic acid,and glutamate metabolic pathways were obviously enriched in the asthenic group,and the glycerol and phospholipid metabolic pathways were obv

关键词： Nervous breakdown Metabolic syndrome Elderly individuals Gastric cancer Nontargeted metabolomics

Impact of Spectral Filter on Phase Modulation Pulse in Fiber Front End System

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Chinese Physics Letters 2011年第3期28卷 89-92页

作者： LI Jing WANG Jian-Jun XU Dang-Peng lin hong-huan GENG Yuan-Chao LI Ming-Zhong DENG Ying ZHU Na ZHANG Rui JING Feng Research Center of Laser Fusion China Academy of Engineering PhysicsPO Box 919-988Mianyang 621900

The transmission characteristics of phase modulation pulse transmitted through the filter in the power amplifier are investigated theoretically and *** narrow bandpass filter can induce large temporal modula-tion depth for the phase modulation pulse and induce double amplitude modulation(AM)if the frequency shift is lower than half bandwidth of the signal *** should choose a wider bandwidth filter to minimize the impact of the filter on the output pulse and suppress the amplified spontaneous emission(ASE)for the power fiber *** results are of benefit to the design of the fiber front end system.

关键词： amplifier fiber Impact

Mitogenome-based phylogeny of mosquitoes(Diptera:Culicidae)

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Insect Science 2024年第2期31卷 599-612页

作者： De-hong Chen Shu-lin He Wen-Bo Fu Zhen-Tian Yan Yun-Jian Hu huan Yuan Ming-Bin Wang Bin Chen Chongqing Key Laboratory of Vector Insects Institute of Entomology and Molecular BiologyChongqing Normal UniversityChongqingChina

Mosquitoes are of great medical significance as vectors of many deadly *** have been widely used in phylogenetic studies,but mitogenome knowledge within the family Culicidae is limited,and Culicidae phylogeny is far from *** this study,we surveyed the mitogenomes of 149 Culicidae species,including 7 newly sequenced *** analysis of 149 mosquito mitogenomes shows gene composition and order to be identical to that of an ancestral insect,and the AT bias,length variation,and codon usage are all consistent with that of other reported Dipteran *** analyses based on the DNA sequences of the 13 protein-coding genes from the 149 species robustly support the monophyly of the subfamily Anophelinae and the tribes Aedini,Culicini,Mansonini,Sabethini,and *** resolve ambiguous relationships between clades within the subfamily Culicinae,we performed topological tests and show that Aedini is a sister to Culicini and that Uranotaenini is a sister to(Mansonini)+(Toxorhynchitini+Sabethini).In addition,we estimated divergence times using a Bayesian relaxation clock based on the sequence data and 3 fossil calibration *** results show mosquitoes diverged during the Early Jurassic with massive Culicinae radiations during the Cretaceous,coincident with the emergence of angiosperms and the burst of mammals and ***,this study,which uses the largest number of Culicidae mitogenomes sequenced to date,comprehensively reveals the mitogenome characteristics and mitogenome-based phylogeny and divergence times of Culicidae,providing information for further studies on the mitogenome,phylogeny,evolution,and taxonomic revision of Culicidae.

关键词： characterization Culicidae evolution mitogenomes mosquitoes phylogeny