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From Phenotypes to Molecules: Revolutionizing Gut Microbiota Identification Methods
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作者 WANG Xuan LV Chang-Long ZHAI Jing-Bo 《中国生物化学与分子生物学报》 CAS CSCD 北大核心 2024年第8期1065-1077,共13页
The gut microbiota is a complex ecosystem composed of many bacteria and their metabolites.It plays an irreplaceable role in human digestion,nutrient absorption,energy supply,fat metabolism,immune regulation,and many o... The gut microbiota is a complex ecosystem composed of many bacteria and their metabolites.It plays an irreplaceable role in human digestion,nutrient absorption,energy supply,fat metabolism,immune regulation,and many other aspects.Exploring the structure and function of the gut microbiota,as well as their key genes and metabolites,will enable the early diagnosis and auxiliary diagnosis of diseases,new treatment methods,better effects of drug treatments,and better guidance in the use of antibiotics.The identification of gut microbiota plays an important role in clinical diagnosis and treatment,as well as in drug research and development.Therefore,it is necessary to conduct a comprehensive review of this rapidly evolving topic.Traditional identification methods cannot comprehensively capture the diversity of gut microbiota.Currently,with the rapid development of molecular biology,the classification and identification methods for gut microbiota have evolved from the initial phenotypic and chemical identification to identification at the molecular level.This review integrates the main methods of gut microbiota identification and evaluates their application.We pay special attention to the research progress on molecular biological methods and focus on the application of high-throughput sequencing technology in the identification of gut microbiota.This revolutionary method for intestinal flora identification heralds a new chapter in our understanding of the microbial world. 展开更多
关键词 gut microbiota 16S rRNA real-time fluorescent qPCR high-throughput sequencing mass spectrum
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Intravoxel incoherent motion and dynamic contrast-enhanced MRI for assessing abnormalities of brucellosis spondylitis without conventional MRI changes
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作者 WANG Haohua ZHAO Pengfei QIAO Pengfei 《中国医学影像技术》 CSCD 北大核心 2024年第8期1226-1230,共5页
Objective To observe the value of intravoxel incoherent motion(IVIM)and dynamic contrast-enhanced MRI(DCE-MRI)for assessing abnormalities of brucellosis spondylitis(BS)without conventional MRI changes.Methods Data of ... Objective To observe the value of intravoxel incoherent motion(IVIM)and dynamic contrast-enhanced MRI(DCE-MRI)for assessing abnormalities of brucellosis spondylitis(BS)without conventional MRI changes.Methods Data of 36 brucellosis patients with definite spinal lesions displayed on conventional MRI(BS 1 group),14 cases without brucellosis infection nor abnormal spinal signals on MRI(control group)and 36 brucellosis patients without definite spinal lesions on conventional MRI(BS 2 group)were retrospectively analyzed.The values of IVIM parameters,including perfusion fraction(f),pure water diffusion coefficient(D)and pseudo-diffusion coefficient(D*),also of DCE-MRI parameters,including time-intensity curve(TIC)type,volume transport constant(K trans),the rate constant(K ep)and volume fraction of extravascular extracellular space per unit tissue volume(V e)were compared among groups.Univariate and multivariate logistic regression were used to screen independent factors for discriminating BS 1 and BS 2.Receiver operating characteristic curves were drawn,and the areas under the curve(AUC)were calculated to evaluate the efficiency of the above parameters for discriminating BS 1 and BS 2.Results Among IVIM parameters,compared with control group,D*values decreased but D values increased in BS 1 group,while D*values increased in BS 2 group(all adjusted P<0.05).Compared with BS 2 group,BS 1 group had higher values of f and D and lower D*(all adjusted P<0.05).In BS 1 group,the TIC types were predominantly typeⅠ(23/36,63.89%),which were wholly or predominantly typeⅢin BS 2 group and control group,and of the former was significantly different with latter 2(both adjusted P<0.05).Compared with control group,K trans increased progressively in both BS 1 and BS 2 groups(both adjusted P<0.05).BS 1 group had lower K ep and higher V e than BS 2 and control groups(all adjusted P<0.05).Among univariate logistic regression models,the model including only f had lower capability for discriminating BS 1 and BS 2(AUC=0.759)than those including D,K trans and V e(AUC=0.951,0.833,0.894,all P<0.05).No significant different was found among multivariate logistic regression model including f and D,model including K trans and V e nor model including all above parameters(all P>0.05).Conclusion Both IVIM and DCE-MRI could be used to evaluate BS abnormality without conventional MRI changes. 展开更多
关键词 BRUCELLOSIS SPONDYLITIS early diagnosis magnetic resonance imaging
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Integrative analysis of bone-formation associated genes and immune cell infiltration in osteoporosis, and the prediction of active ingredients in targeted traditional Chinese medicine
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作者 WANG Kai DONG Ping GUO Hongzhang 《Digital Chinese Medicine》 CAS CSCD 2024年第2期160-170,共11页
Objective To explore the differential expression and mechanisms of bone formation-related genes in osteoporosis(OP)leveraging bioinformatics and machine learning methodologies;and to predict the active ingredients of ... Objective To explore the differential expression and mechanisms of bone formation-related genes in osteoporosis(OP)leveraging bioinformatics and machine learning methodologies;and to predict the active ingredients of targeted traditional Chinese medicine(TCM)herbs.Methods The Gene Expression Omnibus(GEO)and GeneCards databases were employed to conduct a comprehensive screening of genes and disease-associated loci pertinent to the pathogenesis of OP.The R package was utilized as the analytical tool for the identification of differentially expressed genes.Least absolute shrinkage and selection operator(LASSO)logis-tic regression analysis and support vector machine-recursive feature elimination(SVM-RFE)algorithm were employed in defining the genetic signature specific to OP.Gene Ontology(GO)and Kyoto Encyclopedia of Genes and Genomes(KEGG)pathway enrichment analyses for the selected pivotal genes were conducted.The cell-type identification by estimating rela-tive subsets of RNA transcripts(CIBERSORT)algorithm was leveraged to examine the infiltra-tion patterns of immune cells;with Spearman’s rank correlation analysis utilized to assess the relationship between the expression levels of the genes and the presence of immune cells.Coremine Medical Database was used to screen out potential TCM herbs for the treatment of OP.Comparative Toxicogenomics Database(CTD)was employed for forecasting the TCM ac-tive ingredients targeting the key genes.AutoDock Vina 1.2.2 and GROMACS 2020 softwares were employed to conclude analysis results;facilitating the exploration of binding affinity and conformational dynamics between the TCM active ingredients and their biological targets.Results Ten genes were identified by intersecting the results from the GEO and GeneCards databases.Through the application of LASSO regression and SVM-RFE algorithm;four piv-otal genes were selected:coat protein(CP);kallikrein 3(KLK3);polymeraseγ(POLG);and transient receptor potential vanilloid 4(TRPV4).GO and KEGG pathway enrichment analy-ses revealed that these trait genes were predominantly engaged in the regulation of defense response activation;maintenance of cellular metal ion balance;and the production of chemokine ligand 5.These genes were notably associated with signaling pathways such as ferroptosis;porphyrin metabolism;and base excision repair.Immune infiltration analysis showed that key genes were highly correlated with immune cells.Macrophage M0;M1;M2;and resting dendritic cell were significantly different between groups;and there were signifi-cant differences between different groups(P<0.05).The interaction counts of resveratrol;curcumin;and quercetin with KLK3 were 7;3;and 2;respectively.It shows that the interac-tions of resveratrol;curcumin;and quercetin with KLK3 were substantial.Molecular docking and molecular dynamics simulations further confirmed the robust binding affinity of these bioactive compounds to the target genes.Conclusion Pivotal genes including CP;KLK3;POLG;and TRPV4;exhibited commendable significant prognostic value;and played a crucial role in the diagnostic assessment of OP.Resveratrol;curcumin;and quercetin;natural compounds found in TCM;showed promise in their potential to effectively modulate the bone-forming gene KLK3.This study provides a sci-entific basis for the interpretation of the pathogenesis of OP and the development of clinical drugs. 展开更多
关键词 OSTEOPOROSIS Bone formation Differentially expressed genes Biological information Traditional Chinese medicine(TCM) Active ingredients Molecular mechanism
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Regulating crystal phase of TiO_(2) to enhance catalytic activity of Ni/TiO_(2) for solar-driven dry reforming of methane
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作者 HE Zhanjun GONG Kun +3 位作者 DAI Yuanyuan NIU Qiang LIN Tiejun ZHONG Liangshu 《燃料化学学报(中英文)》 EI CAS CSCD 北大核心 2024年第9期1203-1213,共11页
Ni/TiO_(2) catalyst is widely employed for photo-driven DRM reaction while the influence of crystal structure of TiO_(2) remains unclear.In this work,the rutile/anatase ratio in supports was successfully controlled by... Ni/TiO_(2) catalyst is widely employed for photo-driven DRM reaction while the influence of crystal structure of TiO_(2) remains unclear.In this work,the rutile/anatase ratio in supports was successfully controlled by varying the calcination temperature of anatase-TiO_(2).Structural characterizations revealed that a distinct TiO_(x) coating on the Ni nanoparticles(NPs)was evident for Ni/TiO_(2)-700 catalyst due to strong metal-support interaction.It is observed that the TiOx overlayer gradually disappeared as the ratio of rutile/anatase increased,thereby enhancing the exposure of Ni active sites.The exposed Ni sites enhanced visible light absorption and boosted the dissociation capability of CH4,which led to the much elevated catalytic activity for Ni/TiO_(2)-950 in which rutile dominated.Therefore,the catalytic activity of solar-driven DRM reaction was significantly influenced by the rutile/anatase ratio.Ni/TiO_(2)-950,characterized by a predominant rutile phase,exhibited the highest DRM reactivity,with remarkable H_(2) and CO production rates reaching as high as 87.4 and 220.2 mmol/(g·h),respectively.These rates were approximately 257 and 130 times higher,respectively,compared to those obtained on Ni/TiO_(2)-700 with anatase.This study suggests that the optimization of crystal structure of TiO_(2) support can effectively enhance the performance of photothermal DRM reaction. 展开更多
关键词 dry reforming of methane photothermal catalysis crystal phase TiO_(2) metal-support interaction
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Enhanced visible-light photocatalytic oxidation capability of carbon-doped TiO_2 via coupling with fly ash 被引量:13
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作者 Ning An Yuwei Ma +3 位作者 Juming Liu Huiyan Ma Jucai Yang Qiancheng Zhang 《Chinese Journal of Catalysis》 SCIE EI CAS CSCD 北大核心 2018年第12期1890-1900,共11页
A carbon‐doped TiO2/fly ash support(C‐TiO2/FAS)composite photocatalyst was successfully synthesized through sol impregnation and subsequent carbonization.The carbon dopants were derived from the organic species gene... A carbon‐doped TiO2/fly ash support(C‐TiO2/FAS)composite photocatalyst was successfully synthesized through sol impregnation and subsequent carbonization.The carbon dopants were derived from the organic species generated during the synthesis of the C‐TiO2/FAS composite.A series of analytical techniques,such as scanning electron microscopy(SEM),attenuated total reflection‐Fourier transform infrared(ATR‐FTIR)spectroscopy,X‐ray photoelectron spectroscopy(XPS),and ultraviolet‐visible diffuse reflectance spectroscopy(UV‐Vis DRS),were used to characterize the properties of the prepared samples.The results indicated that C‐TiO2 was successfully coated on the FAS surface.Coupling between C‐TiO2 and FAS resulted in the formation of Si–O–C and Al–O–Ti bonds at their interface.The formation of Si–O–C and Al–O–Ti bonds gave rise to a positive shift of the valence band edge of C‐TiO2 and enhanced its oxidation capability of photogenerated holes as well as photodegradation efficiency of methyl orange.Moreover,the C‐TiO2/FAS photocatalyst exhibited favorable reusability and separability.This work may provide a new route for tuning the electronic band structure of TiO2. 展开更多
关键词 Fly ash TiO2 Carbon doping Visible‐light photocatalysis Photocatalytic oxidation
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Effects of spinning rate on structures and electrochemical hydrogen storage performances of RE-Mg-Ni-Mn-based AB_2-type alloys 被引量:6
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作者 Yang-huan ZHANG Wei ZHANG +3 位作者 Xi-ping SONG Pei-long ZHANG Yong-guo ZHU Yan QI 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2016年第12期3219-3231,共13页
La was partially substituted by Ce with the aim of improving the electrochemical hydrogen storage performances ofLa1–xCexMgNi3.5Mn0.5 (x=0, 0.1, 0.2, 0.3, 0.4) alloys, and melt spinning technology was adopted to fabr... La was partially substituted by Ce with the aim of improving the electrochemical hydrogen storage performances ofLa1–xCexMgNi3.5Mn0.5 (x=0, 0.1, 0.2, 0.3, 0.4) alloys, and melt spinning technology was adopted to fabricate the alloys. Theidentification of XRD and SEM reveals that the experimental alloys consist of a major phase LaMgNi4 and a secondary phase LaNi5.The growth of spinning rate results in that the lattice constants and cell volume increase and the grains are markedly refined. Theelectrochemical measurement shows that the as-cast and spun alloys can obtain the maximum discharge capacities just at the firstcycle without any activation needed. With the increase of spinning rate, the discharge capacities of the alloys first increase and thendecline, whereas their cycle stabilities always grow. Moreover, the electrochemical kinetic performances of the alloys first increaseand then decrease with spinning rate growing. 展开更多
关键词 Ni.MH battery hydrogen storage melt spinning discharge capacity KINETICS
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Electrochemical hydrogen storage performance of as-cast and as-spun RE-Mg-Ni-Co-Al-based alloys applied to Ni/MH battery 被引量:5
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作者 Yang-huan ZHANG Ya-qin LI +3 位作者 Hong-wei SHANG Zhong-hui HOU Yan QI Dong-liang ZHAO 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2018年第4期711-721,共11页
The La-Mg-Ni-Co-Al-based AB2-type La0.8-xCe0.2YxMgNi3.4Co0.4Al0.1(x=0,0.05,0.1,0.15,0.2)alloys were prepared via melt spinning.The analyses of the X-ray diffraction(XRD)and scanning electron microscopy(SEM)proved that... The La-Mg-Ni-Co-Al-based AB2-type La0.8-xCe0.2YxMgNi3.4Co0.4Al0.1(x=0,0.05,0.1,0.15,0.2)alloys were prepared via melt spinning.The analyses of the X-ray diffraction(XRD)and scanning electron microscopy(SEM)proved that the experimental alloys contain the main phase LaMgNi4 and the second phase LaNi5.Increasing Y content and spinning rate lead to grain refinement and obvious change of the phase abundance without changing phase composition.Y substitution for La and melt spinning make the life-span of the alloys improved remarkably,which is attributed to the improvement of anti-oxidation,anti-pulverization and anti-corrosion abilities.In addition,the discharge capacity visibly decreases with increasing the Y content,while it firstly increases and then decreases with increasing spinning rate.The electrochemical kinetics increases to the optimum performance and then reduces with increasing spinning rate.Moreover,all the alloys achieve to the highest discharge capacities just at the initial cycle without activation. 展开更多
关键词 Y La substitution spinning rate life-span discharge capacity electrochemical kinetics
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Hydrogen storage behavior of nanocrystalline and amorphous La-Mg-Ni-based LaMg_(12)-type alloys synthesized by mechanical milling 被引量:5
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作者 Yang-huan ZHANG Long-wen LI +3 位作者 Dian-chen FENG Peng-fei GONG Hong-wei SHANG Shi-hai GUO 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2017年第3期551-561,共11页
Nanocrystalline and amorphous LaMg11Ni+x%Ni(x=100,200,mass fraction)alloys were synthesized by mechanicalmilling.The electrochemical hydrogen storage properties of the as-milled alloys were tested by an automatic galv... Nanocrystalline and amorphous LaMg11Ni+x%Ni(x=100,200,mass fraction)alloys were synthesized by mechanicalmilling.The electrochemical hydrogen storage properties of the as-milled alloys were tested by an automatic galvanostatic system.The gaseous hydrogen absorption and desorption properties were investigated by Sievert’s apparatus and differential scanningcalorimeter(DSC)connected with a H2detector.The results indicated that increasing Ni content significantly improves the gaseousand electrochemical hydrogen storage performances of the as-milled alloys.The gaseous hydrogen absorption capacities andabsorption rates of the as-milled alloys have the maximum values with the variation of the milling time.But the hydrogen desorptionkinetics of the alloys always increases with the extending of milling time.In addition,the electrochemical discharge capacity andhigh rate discharge(HRD)ability of the as-milled alloys both increase first and then decrease with milling time prolonging. 展开更多
关键词 Ni-MH battery hydrogen storage alloy mechanical milling discharge capacity KINETICS
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Effects of La substitution on microstructure and hydrogen storage properties of Ti−Fe−Mn-based alloy prepared through melt spinning 被引量:6
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作者 Ze-ming YUAN Zhen QI +3 位作者 Ting-ting ZHAI Hong-zhang WANG Hai-yan WANG Yang-huan ZHANG 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2021年第10期3087-3095,共9页
The as-spun Ti_(1−x)La_(x)Fe_(0.8)Mn_(0.2)(x=0,0.01,0.03,0.06,0.09,molar fraction)alloys were prepared by melt spinning.The effects of La substitution for Ti on the microstructure,hydrogen storage kinetics and thermod... The as-spun Ti_(1−x)La_(x)Fe_(0.8)Mn_(0.2)(x=0,0.01,0.03,0.06,0.09,molar fraction)alloys were prepared by melt spinning.The effects of La substitution for Ti on the microstructure,hydrogen storage kinetics and thermodynamics of TiFe-type Ti−Fe−Mn-based alloy were investigated.The as-spun alloys hold the TiFe single phase,which transforms to TiFeH_(0.06),TiFeH,and TiFeH_(2) hydrides after hydrogenation.La substitution promotes the formation of micro-defects(such as dislocations and grain boundaries)in the alloys,thus facilitating hydrogen diffusion.In addition,the hydrogen storage kinetics properties are improved after introducing La element.With the rise of La content,the hydrogen storage capacity decreases firstly and then increases,but the absolute value of hydriding enthalpy change(|ΔH|)increases firstly and then reduces.When x=0.01,the maximum value of|ΔH|is obtained to be(25.23±0.50)kJ/mol for hydriding,and the alloy has the maximum hydrogen absorption capacity of(1.80±0.04)wt.%under the conditions of 323 K and 3 MPa. 展开更多
关键词 La substitution Ti−Fe−Mn-based alloy melt spinning hydrogen storage kinetics thermodynamics
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Microstructure, hydrogen storage thermodynamics and kinetics of La_5Mg_(95-x)Ni_x(x=5, 10, 15) alloys 被引量:4
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作者 Zhen-yang LI Sheng-li LI +2 位作者 Ze-ming YUAN Yang-huan ZHANG Yan QI 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2019年第5期1057-1066,共10页
The microstructure, hydrogen storage thermodynamics and kinetics of La5Mg95-xNix (x=5, 10, 15) ternary alloys with different Ni contents were investigated. The evolutions of the microstructure and phase of experimenta... The microstructure, hydrogen storage thermodynamics and kinetics of La5Mg95-xNix (x=5, 10, 15) ternary alloys with different Ni contents were investigated. The evolutions of the microstructure and phase of experimental alloys were characterized by X-ray diffractometry and scanning electron microscopy. The hydrogen storage kinetics and thermodynamics, and P-C-I curves were tested using a Sievert apparatus. It is found that increasing Ni content remarkably improves hydrogen storage kinetics but reduces the hydrogen storage capacity of alloys. The highest hydrogen absorption/desorption rate is observed in the La5Mg80Ni15 alloy, with the lowest hydrogen desorption activation value being 57.7 kJ/mol. By means of P-C-I curves and the van’t Hoff equation, it is determined that the thermodynamic performance of the alloy is initially improved and then degraded with increasing Ni content. The La5Mg85Ni10 alloy has the best thermodynamics properties with a hydrogenation enthalpy of -72.1 kJ/mol and hydrogenation entropy of -123.2 J/(mol·K). 展开更多
关键词 hydrogen storage Mg-based alloys thermodynamics performance kinetics performance Ni content
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Tribological properties and thermal-stress analysis of C/C-SiC composites during braking 被引量:10
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作者 Guan-yi CHEN Zhuan LI +5 位作者 Peng XIAO Xi OUYANG Wen-jie MA Peng-tao LI Jin-wei LI Yang LI 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2019年第1期123-131,共9页
The tribological properties and thermal-stress behaviors of C/C-SiC composites during braking were investigated aiming to simulate braking tests of high-speed trains. The temperature and structural fields of C/C-SiC c... The tribological properties and thermal-stress behaviors of C/C-SiC composites during braking were investigated aiming to simulate braking tests of high-speed trains. The temperature and structural fields of C/C-SiC composites during braking were fully coupled and simulated with ANSYS software. The results of tribological tests indicated that the C/C-SiC composites showed excellent static friction coefficient (0.68) and dynamic friction coefficient (average value of 0.36). The highest temperature on friction surface was 445℃. The simulated temperature field showed that the highest temperature which appeared on the friction surface during braking was about 463℃. Analysis regarding thermal-stress field showed that the highest thermal-stress on friction surface was 11.5 MPa. The temperature and thermal-stress distributions on friction surface during braking showed the same tendency. 展开更多
关键词 C/C-SiC composites BRAKE tribological behavior temperature field thermal-stress field
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Residual Condition and Risk Assessment of Heavy Metals in Potato of Inner Mongolia 被引量:2
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作者 Xinxin ZHANG Wenxi WANG +3 位作者 Xin YIN Fujin ZHANG Haifei LIAN Xuejiao WANG 《Agricultural Science & Technology》 CAS 2017年第1期67-71,共5页
[Objective] This study was conducted to investigate the pollution degrees of heavy metals in potato and estimate the risk to human health. [Method] The pollution distribution of 7 heavy metals total As, Hg, Cd, Pb, Cr... [Objective] This study was conducted to investigate the pollution degrees of heavy metals in potato and estimate the risk to human health. [Method] The pollution distribution of 7 heavy metals total As, Hg, Cd, Pb, Cr, Ni and Cu in potato was analyzed by monitoring heavy metals in potato samples in Inner Mongolia. [Result] Residual heavy metals in potato in producing areas in Inner Mongolia satisfied national limit standards, and comprehensive heavy metal pollution index was smaller than 0.7, belonging to the safe grade. Among the 7 heavy metals, Pb and Cr pollution was relatively heavier, and contributed more to the comprehensive pollution index. The THQ values and the TTHQ value of the 7 heavy metals were all lower than 1, indicating that pollution of heavy metals in potato in Inner Mongolia caused no remarkably risk to human health. Among the 7 heavy metals, Cr content contributed the most to risk to human health, and the risk caused by Cr intake through potato was higher than that caused by other heavy metals. In different sampling regions, there were differences in risk of heavy metals in potato to human health. [Conclusion] This study provides an objective scientific basis for management of quality safety risk of potato. 展开更多
关键词 POTATO Heavy Metals Pollution index
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Atomic layer deposition: Catalytic preparation and modification technique for the next generation 被引量:5
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作者 Hongbo Zhang Christopher L. Marshall 《Chinese Journal of Catalysis》 SCIE EI CAS CSCD 北大核心 2019年第9期1311-1323,共13页
Atomic layer deposition(ALD)attracts great attention nowadays due to its ability for designing and modifying catalytic systems at the molecular level.There are several reported review papers published recently discuss... Atomic layer deposition(ALD)attracts great attention nowadays due to its ability for designing and modifying catalytic systems at the molecular level.There are several reported review papers published recently discussing this technique in catalysis.However,the mechanism on how the deposited materials improve the catalyst stability and tune the reaction selectivity is still unclear.Herein,catalytic systems created via ALD on stepwise preparation and/or modification under self-limiting reaction conditions are summarized.The effects of deposited materials in terms of electronic/geometry modification over the catalytic nanoparticles(NPs)are discussed.These effects explain the mechanism of the catalytic stability improvement and the selectivity modification.The unique properties of ALD for designing new catalytic systems are further investigated for building up photocatalytic reaction nanobowls,tandem catalyst and bi-active-component metallic catalytic systems. 展开更多
关键词 Atomic layer deposition Catalyst modification Catalyst preparation Redox properties Terrace site Step site
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Hydrogen storage performances of as-milled REMg_(11)Ni(RE=Y, Sm) alloys catalyzed by MoS_2 被引量:2
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作者 Yang-huan ZHANG Wei ZHANG +4 位作者 Ze-ming YUAN Wen-gang BU Yan QI Xiao-ping DONG Shi-hai GUO 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2018年第9期1828-1837,共10页
To compare the hydrogen storage performances of as-milled REMg11Ni-5MoS2(mass fraction)(RE=Y,Sm)alloys,which were catalyzed by MoS2,the corresponding alloys were prepared.The hydrogen storage performaces of these allo... To compare the hydrogen storage performances of as-milled REMg11Ni-5MoS2(mass fraction)(RE=Y,Sm)alloys,which were catalyzed by MoS2,the corresponding alloys were prepared.The hydrogen storage performaces of these alloys were measured by various methods,such as XRD,TEM,automatic Sievert apparatus,TG and DSC.The results reveal that both of the as-milled alloys exhibit a nanocrystalline and amorphous structure.The RE=Y alloy shows a larger hydrogen absorption capacity,faster hydriding rate,lower initial hydrogen desorption temperature,superior hydrogen desorption property,and lower hydrogen desorption activation energy,which is thought to be the reason of its better hydrogen storage kinetics,as compared with RE=Sm alloy. 展开更多
关键词 Mg-based alloy ball milling CATALYST rare earth element hydrogen storage performance
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English Teachers’ Beliefs About Multilingual Awareness in L3 Learning and Their Teaching Practice in Chinese EFL Context 被引量:1
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作者 Baiyinna WU 《Chinese Journal of Applied Linguistics》 2022年第3期416-432,485,共18页
Teachers’ beliefs toward multilingual awareness in target language learning play a significant role in shaping learners’ attitudes to language awareness, affect learners’ linguistic behavior and teachers’ teaching... Teachers’ beliefs toward multilingual awareness in target language learning play a significant role in shaping learners’ attitudes to language awareness, affect learners’ linguistic behavior and teachers’ teaching practice. Therefore, the present study was aimed to explore English teachers’ beliefs about Inner Mongolian university students’ multilingual awareness in L3 learning and their teaching practice in Chinese EFL context. One hundred English teachers from six universities in Inner Mongolia, China, participated in this investigation. The data was collected through a questionnaire and teacher interviews. The results indicate that English teachers hold positive attitudes to multilingual awareness in general;however, there are belief differences between Mongolian and Han teachers;there exist discrepancies between English teachers’ beliefs about multilingual awareness and their teaching practice, and social-cultural environment, family language policy,teacher identity, learning experience, teaching materials, and, more importantly, teachers’ lack of awareness of fostering learners’ multilingual awareness lead to the discrepancies. The present research highlights the necessity of raising teacher awareness of cultivating multilingual awareness in future teacher development and emphasizes the significance of exploring the potential cognitive advantages of multilingualism in promoting L3 learning and developing English learners’ multilingual competence in the EFL context in China. 展开更多
关键词 teacher belief multilingual awareness multilingual competence metalinguistic awareness cross-linguistic awareness L3 teaching practice
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Optical properties and magnetic properties of antisite-disordered Ni_(1-x)Co_xCr_2O_4 spinels 被引量:1
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作者 Yu GAO Hong CHANG +5 位作者 Qiang WU Hong-yan WANG Yan-bo PANG Fang LIU Hong-jing ZHU Yue-hou YUN 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2017年第4期863-867,共5页
From the UV?Vis absorption spectra,the FT-IR absorption spectra and the Raman spectra,it is deduced that Co ionsprimarily occupy the tetrahedral(A)site,with a minor number of them entering into the octahedral(B)site i... From the UV?Vis absorption spectra,the FT-IR absorption spectra and the Raman spectra,it is deduced that Co ionsprimarily occupy the tetrahedral(A)site,with a minor number of them entering into the octahedral(B)site in the Ni1?xCoxCr2O4compounds.The origin of the position disorder of the Co ions is consistent with the similar ionic radii of the Co ion(0.65?)and theCr ion(0.62?)at B site.The FT-IR peak at about510cm?1shifts towards high frequency side with the increasing cobalt content.Itis resulted from the reduction of the cation?oxygen distance in the octahedron by the replacement of the Ni2+with the Co2+ions.Themagnetic measurement shows that Curie temperatures(TC)are75and90K for the compounds with x=0.2and0.8,respectively. 展开更多
关键词 SPINEL antisite defect electronic transition optical properties magnetic properties
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Mechanism of sodium sulfide on flotation of cyanide-depressed pyrite 被引量:7
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作者 Zhao CAO Peng WANG +2 位作者 Wen-bo ZHANG Xiao-bo ZENG Yong-dan CAO 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2020年第2期484-491,共8页
The mechanism of sodium sulfide(Na2S)on the flotation of cyanide-depressed pyrite using potassium amyl xanthate(PAX)as collector was investigated by flotation test and electrochemical measurements.The flotation result... The mechanism of sodium sulfide(Na2S)on the flotation of cyanide-depressed pyrite using potassium amyl xanthate(PAX)as collector was investigated by flotation test and electrochemical measurements.The flotation results show that both PAX and Na2S can promote the flotation recovery of cyanide-depressed pyrite and their combination can further improve the pyrite flotation recovery.Electrochemical measurements show that PAX and Na2S interacted with cyanide-depressed pyrite through different mechanisms.PAX competed with cyanide and was adsorbed on the pyrite surface in the form of dixanthogen,thus enhancing the hydrophobicity and flotation of cyanide-depressed pyrite.Unlike PAX,Na2S rendered the pyrite surface hydrophobic through the reduction of ferricyanide species and the formation of elemental sulfur S0 and polysulfide Sn2-.The combined application of PAX and Na2S induced superior pyrite flotation recovery because of a synergistic effect between PAX and Na2S. 展开更多
关键词 PYRITE CHALCOCITE FLOTATION CYANIDE DEPRESSION sodium sulfide
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Two new species in the genus Eumerus Meigen(Diptera:Syrphidae)from Inner Mongolia,China 被引量:1
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作者 Mixia SONG Aiping LIU +2 位作者 Keke HUO Li SHI Lin GAN 《Entomotaxonomia》 CSCD 2020年第4期275-281,共7页
This paper describes two new species in the genus Eumerus Meigen,1822(Diptera:Syrphidae)from Alashan Right Banner of China.Eumerus alxaensis Huo&Liu sp.nov.is similar to E.tuberculatus Rondani,but differs from the... This paper describes two new species in the genus Eumerus Meigen,1822(Diptera:Syrphidae)from Alashan Right Banner of China.Eumerus alxaensis Huo&Liu sp.nov.is similar to E.tuberculatus Rondani,but differs from the latter by mesonotum without whitish pollinose middle stripes,tergite 4 with distinctly L-shaped whitish pollinose bands,eyes with long and dense hairs in male but shorter in female,hypandrium ventrally with a semicircular sheet protruding on the middle of lateral margins.Eumerus seximaculatum Huo&Liu sp.nov.is allied to E.strigatus(Fallén),but differs from the latter by eyes bare,vertex covered with pale yellow hairs,whitish pollinose bands on broader tergites,sternite 4 of male with deeply concave posterior margin and male terminalia distinctly different. 展开更多
关键词 Eristalinae Eumerini hover flies taxonomy
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Analysis of Solar Ultraviolet Radiation in Xilinhot 被引量:1
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作者 Ruojing WANG Jiguang SHI 《Agricultural Science & Technology》 CAS 2017年第10期1963-1966,1970,共5页
To further reveal the variation laws of ultraviolet radiation to provide better service for production and people's life, based on observation data of solar ultraviolet radiation obtained by Xilinhot National Climate... To further reveal the variation laws of ultraviolet radiation to provide better service for production and people's life, based on observation data of solar ultraviolet radiation obtained by Xilinhot National Climate Observatory in 2007-2012, the variation laws of solar ultraviolet radiation and its relationship with meteorological factors in different cloud conditions in Xilinhote were analyzed by using the mathematical and statistical methods and SPSS 11.5 software. The results showed that the solar ultraviolet radiation had obvious daily, seasonal and annual variations; the solar ultraviolet radiation was weak in the morning and evening but strong at noon; the maximum appeared from June to August, while the minimum appeared in November and December. It had significant correlation with total solar radiation, photosynthetically active radiation, air temperature, air humidity and ground temperature (0-5 cm). At present, the maximum intensity of ultraviolet radiation (UV-B) was 0.20-1.91 W/m2 from January to March and 0.13-1.43 W/m2 from October to De- cember respectively, which were lower than the safety standard for people and animals (2 W/mZ). However, the maximum might appear from April to September, ranging from 2.02 to 3.39 W/m2, which was easy to bring a threat and harm to people and animals. 展开更多
关键词 Solar ultraviolet radiation Cloud conditions LAWS CORRELATION
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Three new species of the genus Platypalpus(Diptera:Empididae)from Sichuan,China 被引量:1
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作者 Meilin LI Shang GAO +1 位作者 Chen LIN Ding YANG 《Entomotaxonomia》 CSCD 2021年第3期189-195,共7页
Platypalpus Macquart is one of the largest genera in the family Empididae with over 550 known species distributed worldwide.Eight species were known to occur in Sichuan.Here three new species belonging to the Platypal... Platypalpus Macquart is one of the largest genera in the family Empididae with over 550 known species distributed worldwide.Eight species were known to occur in Sichuan.Here three new species belonging to the Platypalpus longicornis species group are described from Sichuan:Platypalpus breviarista sp.nov.,Platypalpus minor sp.nov.,and Platypalpus yadinganus sp.nov.A key to the species of Platypalpus from Sichuan is presented. 展开更多
关键词 dance fly taxonomy key
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