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Protective mechanism of Coprinus comatus polysaccharide on acute alcoholic liver injury in mice,the metabolomics and gut microbiota investigation 被引量:3
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作者 Jinyan Yu Jianguang sun +4 位作者 min sun Weidong Li Dongmei Qi Yongqing Zhang Chunchao Han 《Food Science and Human Wellness》 SCIE CSCD 2024年第1期401-413,共13页
Coprinus comatus polysaccharide(CCP)has significant hepatoprotective effect.To explore hepatoprotective mechanism of CCP,the study analyzed preventive effect of CCP on acute alcoholic liver injury in mice by histopath... Coprinus comatus polysaccharide(CCP)has significant hepatoprotective effect.To explore hepatoprotective mechanism of CCP,the study analyzed preventive effect of CCP on acute alcoholic liver injury in mice by histopathological examination and biochemical analysis.Simultaneously,hepatoprotective mechanism was also analyzed in conjunction with metabolomics and proliferation of gut microbiota.The results showed that CCP significantly decreased alanine aminotransferase(ALT),aspartate aminotransferase(AST)and triglyceride(TG)levels in serum of alcoholic liver disease(ALD)mice.Histopathological examination showed that CCP can significantly improve liver damage.Metabolomics results showed that there were significant differences in the level of metabolites in liver tissue of control group,ALD group and CCP group,including taurine,xanthosine,fumaric acid and arachidonic acid,among others.Metabolites pathways analysis showed that hepatoprotective effect of CCP was related to energy metabolism,biosynthesis of unsaturated fatty acids,amino acids metabolism and lipid metabolism.Additionally,CCP inhibited an increase in the number of Clostridium perfringens,Enterobacteriaceae and Enterococcus,and a decrease in the number of Lactobacillus and Bifidobacterium in the gut of ALD mice.All these findings suggested that CCP treatment reversed the phenotype of ethanol-induced liver injury and the associated metabolites pathways. 展开更多
关键词 Coprinus comatus POLYSACCHARIDE Alcoholic liver disease Metabolomics Gut microbiota
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Mechanistic investigation on Ag-Cu_(2)O in electrocatalytic CO_(2) to CH_(4) by in situ/operando spectroscopic and theoretical analysis 被引量:1
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作者 min sun Luxiao Zhang +10 位作者 Fuli Tian Jiaxin Li Yanqiu Lei Heng Zhang Lifeng Han Zhihua Guo Yonghui Gao Fenrong Liu Yan Wang Luhui Wang Shanghong Zeng 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2024年第1期521-531,I0012,共12页
Silver-copper electrocatalysts have demonstrated effectively catalytic performance in electroreduction CO_(2) toward CH_(4),yet a revealing insight into the reaction pathway and mechanism has remained elusive.Herein,w... Silver-copper electrocatalysts have demonstrated effectively catalytic performance in electroreduction CO_(2) toward CH_(4),yet a revealing insight into the reaction pathway and mechanism has remained elusive.Herein,we construct chemically bonded Ag-Cu_(2)O boundaries,in which the complete reduction of Cu_(2)O to Cu has been strongly impeded owing to the presence of surface Ag shell.The interfacial confinement effect helps to maintain Cu^(+)sites at the Ag-Cu_(2)O boundaries.Using in situ/operando spectroscopy and theoretical simulations,it is revealed that CO_(2) is enriched at the Ag-Cu_(2)O boundaries due to the enhanced physisorption and chemisorption to CO_(2),activating CO_(2) to form the stable intermediate^(*)CO.The boundaries between Ag shell and the Cu_(2)O mediate local^(*)CO coverage and promote^(*)CHO intermediate formation,consequently facilitating CO_(2)-to-CH_(4) conversion.This work not only reveals the structure-activity relationships but also offers insights into the reaction mechanism on Ag-Cu catalysts for efficient electrocatalytic CO_(2) reduction. 展开更多
关键词 Ag shell Interfacial confinement effect Cu~+ Local*CO coverage CO_(2)reduction
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Reconstructing historical forest fire risk in the non-satellite era using the improved forest fire danger index and long short-term memory deep learning-a case study in Sichuan Province,southwestern China
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作者 Yuwen Peng Huiyi Su +1 位作者 min sun mingshi Li 《Forest Ecosystems》 SCIE CSCD 2024年第1期87-99,共13页
Historical forest fire risk databases are vital for evaluating the effectiveness of past forest management approaches,enhancing forest fire warnings and emergency response capabilities,and accurately budgeting potenti... Historical forest fire risk databases are vital for evaluating the effectiveness of past forest management approaches,enhancing forest fire warnings and emergency response capabilities,and accurately budgeting potential carbon emissions resulting from fires.However,due to the unavailability of spatial information technology,such databases are extremely difficult to build reliably and completely in the non-satellite era.This study presented an improved forest fire risk reconstruction framework that integrates a deep learning-based time series prediction model and spatial interpolation to address the challenge in Sichuan Province,southwestern China.First,the forest fire danger index(FFDI)was improved by supplementing slope and aspect information.We compared the performances of three time series models,namely,the autoregressive integrated moving average(ARIMA),Prophet and long short-term memory(LSTM)in predicting the modified forest fire danger index(MFFDI).The bestperforming model was used to retrace the MFFDI of individual stations from 1941 to 1970.Following this,the Anusplin spatial interpolation method was used to map the distributions of the MFFDI at five-year intervals,which were then subjected to weighted overlay with the distance-to-river layer to generate forest fire risk maps for reconstructing the forest fire danger database.The results revealed LSTM as the most accurate in fitting and predicting the historical MFFDI,with a fitting determination coefficient(R^2)of 0.709,mean square error(MSE)of0.047,and validation R^2 and MSE of 0.508 and 0.11,respectively.Independent validation of the predicted forest fire risk maps indicated that 5 out of 7 historical forest fire events were located in forest fire-prone areas,which is higher than the results determined from the original FFDI(2 out of 7).This proves the effectiveness of the improved MFFDI and indicates a high level of reliability of the historical forest fire risk reconstruction method proposed in this study. 展开更多
关键词 Forest fire risk reconstruction MFFDI Time series models LSTM ARIMA PROPHET Anusplin
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Nonlinear interaction of head-on solitary waves in integrable and nonintegrable systems
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作者 张树甜 刘世鲲 +3 位作者 矫滕菲 孙敏 胡凤兰 黄德财 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第5期480-487,共8页
This study numerically investigates the nonlinear interaction of head-on solitary waves in a granular chain(a nonintegrable system)and compares the simulation results with the theoretical results in fluid(an integrabl... This study numerically investigates the nonlinear interaction of head-on solitary waves in a granular chain(a nonintegrable system)and compares the simulation results with the theoretical results in fluid(an integrable system).Three stages(the pre-in-phase traveling stage,the central-collision stage,and the post-in-phase traveling stage)are identified to describe the nonlinear interaction processes in the granular chain.The nonlinear scattering effect occurs in the central-collision stage,which decreases the amplitude of the incident solitary waves.Compared with the leading-time phase in the incident and separation collision processes,the lagging-time phase in the separation collision process is smaller.This asymmetrical nonlinear collision results in an occurrence of leading phase shifts of time and space in the post-in-phase traveling stage.We next find that the solitary wave amplitude does not influence the immediate space-phase shift in the granular chain.The space-phase shift of the post-in-phase traveling stage is only determined by the measurement position rather than the wave amplitude.The results are reversed in the fluid.An increase in solitary wave amplitude leads to decreased attachment,detachment,and residence times for granular chains and fluid.For the immediate time-phase shift,leading and lagging phenomena appear in the granular chain and the fluid,respectively.These results offer new knowledge for designing mechanical metamaterials and energy-mitigating systems. 展开更多
关键词 integrable system nonintegrable system granular chain solitary wave
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V0405 Dra:A New Deep and Low Mass Ratio Contact Binary with Extremely Fast Decrease in the Orbital Period
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作者 Chao-Yue Li Lin-Qiao Jiang +5 位作者 Jie Zheng Yi-Man Liu Xiao-Yu Long min sun Han-Lu Zhang Xiao-Man Tian 《Research in Astronomy and Astrophysics》 SCIE CAS CSCD 2024年第6期287-293,共7页
V0405 Dra is a W UMa-type binary star.Based on the TESS data,we have conducted an orbital period study and performed a light curve analysis for the system.The orbital period study reveals that the O-C curve for V0405 ... V0405 Dra is a W UMa-type binary star.Based on the TESS data,we have conducted an orbital period study and performed a light curve analysis for the system.The orbital period study reveals that the O-C curve for V0405 Dra exhibits secular decrease at an extremely high rate of d P/dt=-2.71×10^(-6)day year^(-1),along with periodic variations characterized by an amplitude of A_(3)=0.0032 day and a period of P_(3)=1.413 years.The orbital periodic change is possibly due to the light-travel time effect resulting from an additional third body in the system,for which we estimate a minimum mass of M_(3)=0.77M_(⊙).By employing the 2013 version of the Wilson-Devinney(W-D)method to synthesize a light curve,we derived photometric solutions indicating that V0405 Dra is a new deep(f=68.7%)and low-mass ratio(q=0.175)contact binary.The fast decrease in its orbital period is likely caused by mass transfer from the more massive primary star to the less massive secondary star,or due to angular momentum loss.With further mass transfer and loss of angular momentum,the binary will gradually evolve into a tighter contact configuration,eventually leading to a merger into a single star,following the evolutionary paths suggested for such deep and low mass ratio contact binaries. 展开更多
关键词 (stars:)binaries(including multiple):close (stars:)binaries:eclipsing stars:individual(V0405 Dra)
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Simultaneous determination of captopril and hydrochlorothiazide by time-resolved chemiluminescence with artificial neural network calibration 被引量:5
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作者 Han-Chun Yao min sun +2 位作者 Xiao-Feng Yang Zhen-Zhong Zhang Hua Li 《Journal of Pharmaceutical Analysis》 SCIE CAS 2011年第1期32-38,共7页
The combined use of chemometrics and chemiluminescence(CL)measurements,with the aid of the stopped-flow mixing technique,developed a simple time-resolved CL method for the simultaneous determination of captopril(CP... The combined use of chemometrics and chemiluminescence(CL)measurements,with the aid of the stopped-flow mixing technique,developed a simple time-resolved CL method for the simultaneous determination of captopril(CPL)and hydrochlorothiazide(HCT).The stopped-flow technique in a continuous-flow system was employed in this work in order to emphasize the kinetic differences between the two analytes in cerium(IV)-rhodamine 6G CL system.After the flow was stopped,an initial rise of CL signal was observed for HCT standards,while a direct decay of CL signal was obtained for CPL standards.The mixed CL signal was monitored and recorded on the whole process of continuous-flow/stopped-flow,and the obtained data were processed by the chemometric approach of artificial neural network.The relative prediction error(RPE)of CPL and HCT was 5.9% and 8.7%,respectively.The recoveries of CPL and HCT in tablets were found to fall in the range between 95% and 106%.The proposed method was successfully applied to the simultaneous determination of CPL and HCT in a compound pharmaceutical formulation. 展开更多
关键词 time-resolved chemiluminescence artificial neural network CAPTOPRIL HYDROCHLOROTHIAZIDE
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Continental reconstruction and metallogeny of the Circum-Junggar areas and termination of the southern Central Asian Orogenic Belt 被引量:21
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作者 Wenjiao Xiao min sun M.Santosh 《Geoscience Frontiers》 SCIE CAS CSCD 2015年第2期137-140,共4页
Continental reconstructions in Central Asia are represented by orogenesis along some large orogenic belts in the Altaid collage (Fig. 1 ) or Central Asian Orogenic Belt (CAOB), which separate the East European and... Continental reconstructions in Central Asia are represented by orogenesis along some large orogenic belts in the Altaid collage (Fig. 1 ) or Central Asian Orogenic Belt (CAOB), which separate the East European and Siberian cratons to the north from the Tarim and North China cratons to the south ($eng0r et al,, 1993; Jahn et al., 2004; Windley et al., 2007; Qu et al., 2008; Xiao et al., 2010; Xiao and Santosh, 2014). The Altaid Collage was characterized by complex long tectonic and structural evolution from at least ca. 1.0 Ga to late Paleozoic-early Mesozoic with considerable continental growth (Khain et al., 2002; Jahn et al., 2004; Xiao et al., 2009, 2014; KrOner et al., 2014), followed by Cenozoic intracontinental evolution related to far-field effect of the collision of the In- dian Plate to the Eurasian Accompanying with these complex world-class ore deposits developed 2001; Goldfarb et al., 2003, 2014). Plate (Cunningham, 2005). geodynamic evolutions, many (Qin, 2000; Yakubchuk et al,2001; Goldfarb et al., 2003, 2014). 展开更多
关键词 Continental reconstruction and metallogeny of the Circum-Junggar areas and termination of the southern Central Asian Orogenic Belt
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Nonreciprocity of energy transfer in a nonlinear asymmetric oscillator system with various vibration states 被引量:1
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作者 Jian’en CHEN Jianling LI +3 位作者 minghui YAO Jun LIU Jianhua ZHANG min sun 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI CSCD 2023年第5期727-744,共18页
The nonreciprocity of energy transfer is constructed in a nonlinear asymmetric oscillator system that comprises two nonlinear oscillators with different parameters placed between two identical linear oscillators.The s... The nonreciprocity of energy transfer is constructed in a nonlinear asymmetric oscillator system that comprises two nonlinear oscillators with different parameters placed between two identical linear oscillators.The slow-flow equation of the system is derived by the complexification-averaging method.The semi-analytical solutions to this equation are obtained by the least squares method,which are compared with the numerical solutions obtained by the Runge-Kutta method.The distribution of the average energy in the system is studied under periodic and chaotic vibration states,and the energy transfer along two opposite directions is compared.The effect of the excitation amplitude on the nonreciprocity of the system producing the periodic responses is analyzed,where a three-stage energy transfer phenomenon is observed.In the first stage,the energy transfer along the two opposite directions is approximately equal,whereas in the second stage,the asymmetric energy transfer is observed.The energy transfer is also asymmetric in the third stage,but the direction is reversed compared with the second stage.Moreover,the excitation amplitude for exciting the bifurcation also shows an asymmetric characteristic.Chaotic vibrations are generated around the resonant frequency,irrespective of which linear oscillator is excited.The excitation threshold of these chaotic vibrations is dependent on the linear oscillator that is being excited.In addition,the difference between the energy transfer in the two opposite directions is used to further analyze the nonreciprocity in the system.The results show that the nonreciprocity significantly depends on the excitation frequency and the excitation amplitude. 展开更多
关键词 NONRECIPROCITY strong nonlinearity energy transfer chaotic vibration higher branch of response
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Ultralow Ag-assisted carbon-carbon coupling mechanism on Cu-based catalysts for electrocatalytic CO_(2) reduction 被引量:1
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作者 Lei Xue Qi-Yuan Fan +5 位作者 Yuansong Zhao Yang Liu Heng Zhang min sun Yan Wang Shanghong Zeng 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2023年第7期414-422,I0009,共10页
Electrocatalytic CO_(2) reduction to C2H4supplies an economically viable route for CO_(2) fixation with the integration of intermittent renewable energy.Cu-based catalysts are capable of catalyzing CO_(2) to C_(2)H_(4... Electrocatalytic CO_(2) reduction to C2H4supplies an economically viable route for CO_(2) fixation with the integration of intermittent renewable energy.Cu-based catalysts are capable of catalyzing CO_(2) to C_(2)H_(4),while suffering from the high overpotential and low Faradaic efficiency.In this joint experimentalcomputational work,an Ag-assisted carbon-carbon coupling is exploited on Cu-based catalysts.A systematic characterization analysis suggests that an ultralow quantity of Ag atoms in the Cu catalysts motivates electron transfer from Cu to Ag,regulating the electronic state of highly dispersed Ag.Meanwhile,the Ag incorporation provokes the formation of more oxygen defects on the catalyst surface,improving the adsorption and activation of CO_(2) molecules.Density functional theory studies prove the improvement effect of Ag for CO_(2)to COOH^(*).^(*)CO hydrogenation is energetically more favorable than^(*)CO dimerization pathway,and two^(*)CHO dimerization produces^(*)OCHCHO^(*) key intermediates,which greatly reduces the energy barrier for C_(2)H_(4) formation. 展开更多
关键词 Silver-copper Ethylene Density functional theory Reaction mechanism CO_(2)reduction
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Characterization of gut microbial and metabolite alterations in faeces of Goto Kakizaki rats using metagenomic and untargeted metabolomic approach
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作者 Jin-Dong Zhao min sun +5 位作者 Yan Li Chan-Juan Yu Ruo-Dong Cheng Si-Hai Wang Xue Du Zhao-Hui Fang 《World Journal of Diabetes》 SCIE 2023年第3期255-270,共16页
BACKGROUND In recent years,the incidence of type 2 diabetes(T2DM)has shown a rapid growth trend.Goto Kakizaki(GK)rats are a valuable model for the study of T2DM and share common glucose metabolism features with human ... BACKGROUND In recent years,the incidence of type 2 diabetes(T2DM)has shown a rapid growth trend.Goto Kakizaki(GK)rats are a valuable model for the study of T2DM and share common glucose metabolism features with human T2DM patients.A series of studies have indicated that T2DM is associated with the gut microbiota composition and gut metabolites.We aimed to systematically characterize the faecal gut microbes and metabolites of GK rats and analyse the relationship between glucose and insulin resistance.AIM To evaluate the gut microbial and metabolite alterations in GK rat faeces based on metagenomics and untargeted metabolomics.METHODS Ten GK rats(model group)and Wistar rats(control group)were observed for 10 wk,and various glucose-related indexes,mainly including weight,fasting blood glucose(FBG)and insulin levels,homeostasis model assessment of insulin resistance(HOMA-IR)and homeostasis model assessment ofβcell(HOMA-β)were assessed.The faecal gut microbiota was sequenced by metagenomics,and faecal metabolites were analysed by untargeted metabolomics.Multiple metabolic pathways were evaluated based on the differential metabolites identified,and the correlations between blood glucose and the gut microbiota and metabolites were analysed.RESULTS The model group displayed significant differences in weight,FBG and insulin levels,HOMA-IR and HOMA-βindexes(P<0.05,P<0.01)and a shift in the gut microbiota structure compared with the control group.The results demonstrated significantly decreased abundances of Prevotella sp.CAG:604 and Lactobacillus murinus(P<0.05)and a significantly increased abundance of Allobaculum stercoricanis(P<0.01)in the model group.A correlation analysis indicated that FBG and HOMA-IR were positively correlated with Allobaculum stercoricanis and negatively correlated with Lactobacillus murinus.An orthogonal partial least squares discriminant analysis suggested that the faecal metabolic profiles differed between the model and control groups.Fourteen potential metabolic biomarkers,including glycochenodeoxycholic acid,uric acid,13(S)-hydroxyoctadecadienoic acid(HODE),N-acetylaspartate,β-sitostenone,sphinganine,4-pyridoxic acid,and linoleic acid,were identified.Moreover,FBG and HOMA-IR were found to be positively correlated with glutathione,13(S)-HODE,uric acid,4-pyridoxic acid and allantoic acid and negatively correlated with 3-α,7-α,chenodeoxycholic acid glycine conjugate and 26-trihydroxy-5-β-cholestane(P<0.05,P<0.01).Allobaculum stercoricanis was positively correlated with linoleic acid and sphinganine(P<0.01),and 2-methyl-3-hydroxy-5-formylpyridine-4-carboxylate was negatively associated with Prevotella sp.CAG:604(P<0.01).The metabolic pathways showing the largest differences were arginine biosynthesis;primary bile acid biosynthesis;purine metabolism;linoleic acid metabolism;alanine,aspartate and glutamate metabolism;and nitrogen metabolism.CONCLUSION Metagenomics and untargeted metabolomics indicated that disordered compositions of gut microbes and metabolites may be common defects in GK rats. 展开更多
关键词 Type 2 diabetes mellitus Gut microbial Metabolites Goto-Kakizaki rats METAGENOMICS Untargeted metabolomics
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藜麦基因组学与重要农艺性状位点研究进展 被引量:5
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作者 李玲红 苟彤 +5 位作者 任爱霞 丁鹏程 林文 武祥云 孙敏 高志强 《遗传》 CAS CSCD 北大核心 2022年第11期1009-1027,共19页
藜麦(Chenopodium quinoa Willd.)作为20世纪新兴的健康食物,因其营养成分全面、抗逆性强等特性备受关注,在国际上享有“营养黄金”、“素食之王”、“未来食品”的美誉。近年来随着基因组学和高通量测序技术的快速发展,藜麦高质量的全... 藜麦(Chenopodium quinoa Willd.)作为20世纪新兴的健康食物,因其营养成分全面、抗逆性强等特性备受关注,在国际上享有“营养黄金”、“素食之王”、“未来食品”的美誉。近年来随着基因组学和高通量测序技术的快速发展,藜麦高质量的全基因组序列得以完成并开展了系列关键基因功能研究。本文总结了藜麦基因组学、重要转录因子基因家族分析、遗传图谱构建和重要性状QTL定位和重要农艺和产量性状基因的研究进展。此外,针对目前藜麦育种的现状,本文还提出了藜麦育种存在的5个关键问题,并指出了未来藜麦遗传改良和育种的4个重要方向,旨在为实现未来藜麦的定向遗传改良提供参考。 展开更多
关键词 藜麦 基因组学 遗传育种 性状 基因
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What Happened in the Trans-North China Orogen in the Period 2560-1850 Ma? 被引量:16
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作者 Guochun ZHAO LIU Shuwen +5 位作者 min sun LI Sanzhong Simon WILDE Xiaoping XIA Jian ZHANG Yanhong HE 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2006年第6期790-806,共17页
The Trans-North China Orogen (TNCO) was a Paleoproterozic continent-continent collisional belt along which the Eastern and Western Blocks amalgamated to form a coherent North China Craton (NCC). Recent geological,... The Trans-North China Orogen (TNCO) was a Paleoproterozic continent-continent collisional belt along which the Eastern and Western Blocks amalgamated to form a coherent North China Craton (NCC). Recent geological, structural, geochemical and isotopic data show that the orogen was a continental margin or Japan-type arc along the western margin of the Eastern Block, which was separated from the Western Block by an old ocean, with eastward-directed subduction of the oceanic lithosphere beneath the western margin of the Eastern Block. At 2550-2520 Ma, the deep subduction caused partial melting of the medium-lower crust, producing copious granitoid magma that was intruded into the upper levels of the crust to form granitoid plutons in the low- to medium-grade granite-greeustone terranes. At 2530-2520 Ma, subduction of the oceanic lithosphere caused partial melting of the mantle wedge, which led to underplating of mafic magma in the lower crust and widespread mafic and minor felsic volcanism in the arc, forming part of the greenstone assemblages. Extension driven by widespread mafic to felsic volcanism led to the development of back-arc and/or intra-arc basins in the orogen. At 2520-2475 Ma, the subduction caused further partial melting of the lower crust to form large amounts of tonalitic-trondhjemitic-granodioritic (TTG) magmatism. At this time following further extension of back-arc basins, episodic granitoid magmatism occurred, resulting in the emplacement of 2360 Ma, -2250 Ma 2110-21760 Ma and -2050 Ma granites in the orogen. Contemporary volcano-sedimentary rocks developed in the back-arc or intra-are basins. At 2150-1920 Ma, the orogen underwent several extensional events, possibly due to subduction of an oceanic ridge, leading to emplacement of mafic dykes that were subsequently metamorphosed to amphibolites and medium- to high-pressure mafic granulites. At 1880-1820 Ma, the ocean between the Eastern and Western Blocks was completely consumed by subduction, and the dosing of the ocean led to the continent-arc-continent collision, which caused large-scale thrusting and isoclinal folds and transported some of the rocks into the lower crustal levels or upper mantle to form granulites or eclogites. Peak metamorphism was followed by exhumation/uplift, resulting in widespread development of asymmetric folds and symplectic textures in the rocks. 展开更多
关键词 ARCHEAN PALEOPROTEROZOIC SUBDUCTION collision Tram-North China Orogen North China Craton
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U-Pb Zircon Dating of the Granitic Conglomerates of the Hutuo Group:Affinities to the Wutai Granitoids and Significance to the Tectonic Evolution of the Trans-North China Orogen 被引量:16
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作者 Jian ZHANG Guochun ZHAO +4 位作者 LI Sanzhong min sun LIU Shuwen Xiaoping XIA Yanhong HE 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2006年第6期886-898,共13页
The Wutai Complex associated with the adjacent Fuping and Hengshan Complexes represents the best and dassical cross-section in the middle segment of the Trans-North China Orogen, generally divided into Eastern and Wes... The Wutai Complex associated with the adjacent Fuping and Hengshan Complexes represents the best and dassical cross-section in the middle segment of the Trans-North China Orogen, generally divided into Eastern and Western Blocks. Unconformably overlying the Wutai and Fuping Complexes is the Hutuo Group considered as the youngest lithostratigraphic unit in the region and important both for interpreting Precambrian history as well as the overall evolution of the Trans-North China Orogen. Lack of knowledge about provenance of the sedimentary rocks in this group has hindered understanding of the depositional environments and tectonic significance. LA-ICP-MS was applied to obtain U-Pb zircon ages for the granitic pebbles, the lowest lithostratigraphic rock of the Hutuo Group, which, combined with previous lithostratigraphic, geochronological, structural and metamorphic data, provides new constraints on the sedimentary provenance and tectonic evolution of the region. The sequence of the Hutuo Group ranges upward from lower basal conglomerates and volcaniclastic rocks (Doucun Subgroup), through clastic sediments, slates, dolomites and marbles (Dongye Subgroup), to sandstones and conglomerates at the top (Guojiazhai Subgroup). Zircons from granitic pebbles preserved in the Doucun Subgroup basal conglomerates give weighted mean ^207pb/^206pb ages between 2517 Ma and 2566 Ma, which are the same as those for the late Archean Wutai Granitoids, indicating that the pebbles were derived from the Wutai granitic intrusions (2566-2515 Ma). Based on the new data and previous studies, combined with an igneous zircon crystallization age of 2087±9 Ma obtained for volcanics in the Hutuo Group, the Hutuo Group was deposited in a subduction-related retro-arc foreland basin environment that developed behind the Wutai arc during the eastward-directed subduction of the Western Block beneath the western margin of the Eastern Block. This basin underwent long-lived sedimentation and finally closed during the -1850 Ma collisional event that resulted in the final amalgamation of the North China Craton. 展开更多
关键词 Trans-North China Orogen PALEOPROTEROZOIC Wutai Complex Hutuo Group CONGLOMERATES
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U-Pb Age and Hf Isotope Study of Detrital Zircons from the Wanzi Supracrustals:Constraints on the Tectonic Setting and Evolution of the Fuping Complex,Trans-North China Orogen 被引量:13
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作者 Xiaoping XIA min sun +5 位作者 Guochun ZHAO WU Fuyuan XU Ping Jian ZHANG Yanhong HE ZHANG Jiheng 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2006年第6期844-863,共20页
Located in the middle segment of the Trans-North China Orogen, the Fuping Complex is considered as a critical area in understanding the evolution history of the North China Craton (NCC). The complex is composed of v... Located in the middle segment of the Trans-North China Orogen, the Fuping Complex is considered as a critical area in understanding the evolution history of the North China Craton (NCC). The complex is composed of various high-grade and multiply deformed rocks, including gray gneiss, basic granulite, amphibolite, fine-grained gneiss and marble, metamorphosed to upper amphibolite or granulite facies. It can be divided into four rock units: the Fuping TTG gneisses, Longquanguan augen gneisses, Wanzi supracrustals, and Nanying granitic gneisses. U-Pb age and Hf isotope compositions of about 200 detrital zircons from the Wanzi supracrustals of the Fuping Complex have been analyzed. The data on metamorphic zircon rims give ages of 1.82-1.84 Ga, corresponding to the final amalgamation event of the NCC, whereas the data for igneous zircon cores yield two age populations at -2.10 and -2.51 Ga, with some inherited ages scattering between 2.5 and 2.9 Ga. These results suggest that the Wanzi supracrustals were derived from the Fuping TTG gneisses (-2.5 Ga) and the Nanying granitic gneisses (2.0-2.1 Ga) and deposited between 2.10 and 1.84 Ga. All zircons with -2.51 Ga age have positive initial εHf values from +1.4 to +10.9, suggesting an important crustal growth event at -2.5 Ga through the addition of juvenile materials from the mantle. The Hf isotope data for the detrital zircons further imply that the 2.8 Ga rocks are important components in the lower crust, which is consistent with a suggestion from Nd isotope data for the Eastern Block. The zircons of 2.10 Ga population have initial εHf values of-4.9 to +6.1, interpreted as mixing of crustal re-melt with minor juvenile material contribution at 2.1 Ga. These results are distinct from that for the Western Block, supporting that the Fuping Complex was emplaced in a tectonic active environment at the western margin of the Eastern Block. 展开更多
关键词 detrital zircons U-Pb age and Hf isotope Fuping Complex North China Craton
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Effects of chromium on the corrosion and electrochemical behaviors of ultra high strength steels 被引量:13
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作者 Jin-yan Zhong min sun +2 位作者 Da-bo Liu Xiao-gang Li Tian-qi Liu 《International Journal of Minerals,Metallurgy and Materials》 SCIE EI CAS CSCD 2010年第3期282-289,共8页
The effects of chromium on the corrosion and the electrochemical behaviors of ultra high strength steels were studied by the salt spray test and electrochemical methods. The results show that ultra high strength steel... The effects of chromium on the corrosion and the electrochemical behaviors of ultra high strength steels were studied by the salt spray test and electrochemical methods. The results show that ultra high strength steels remain martensite structures and have anodic dissolution characteristic with an increase of chromium content. There is no typical passive region on the polarization curves of an ultra high strength stainless steel, AerMet 100 steel, and 300M steel. However, chromium improves the corrosion resistance of the stainless steel remarkably. It has the slowest corrosion rate in the salt spray test, one order of magnitude less than that of AerMet 100 and 300M steels. With the increase of chromium content, the polarization resistance becomes larger, the corrosion potential shifts towards the positive direction with a value of 545 mV, and the corrosion current density decreases in electrochemical measures in 3.5wt% NaCl solutions. Because of the higher content of chromium, the ultra high strength stainless steel has a better corrosion resistance than AerMet 100 and 300M steels. 展开更多
关键词 ultra high strength steel corrosion rate CHROMIUM electrochemical behavior
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Geochronology and geochemistry of Late Carboniferous dykes in the Aqishan-Yamansu belt,eastern Tianshan:Evidence for a post-collisional slab breakoff 被引量:8
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作者 Xiaoping Long Bin Wu +3 位作者 min sun Chao Yuan Wenjiao Xiao Rui Zuo 《Geoscience Frontiers》 SCIE CAS CSCD 2020年第1期347-362,共16页
With aim of providing constraints on the Late Paleozoic tectonic evolution of the southern Central Asian Orogenic Belt(CAOB),an integrated study was conducted on the geochronological and geochemical data for dioritic,... With aim of providing constraints on the Late Paleozoic tectonic evolution of the southern Central Asian Orogenic Belt(CAOB),an integrated study was conducted on the geochronological and geochemical data for dioritic,granitic and diabase dykes from the Aqishan-Yamansu belt in the eastern Tianshan,NW China.Zircon U-Pb dating indicates that the dioritic and granitic dykes were both emplaced in the Late Carboniferous(~311 Ma and^315 Ma).The dioritic dykes show adakitic characteristics and have high Na2 O and positiveεHf(t)values(+12 to+17),which suggest an origin from partial melts of a subducted oceanic slab.The granitic dykes have high SiO2 and K2 O contents and are characterized by en riched light rare earth elements(LREE)and slightly flat heavy rare earth elements(HREE),with negative Eu and Nb-Ta-Ti anomalies.These dykes are alkali-calcic and show geochemical features of highly fractionated Itype granites.Their positiveεHf(t)values(+16 to+17)suggest that they were derived from a juvenile accreted oceanic crustal sou rce.The coeval diabase dykes have low SiO2 and K2 O contents but high TiO2,MgO and Mg#(54-59).They are enriched in LREE and show characteristics of enriched mid-ocean ridge basalts(E-MORB).The relatively high Ba/Th,slightly low Th/Ta ratios,and negative Nb-Ta anomalies imply a mantle source metasomatised by slab-derived fluids.Thus,these basic dykes were generated likely by partial melting of the upwelling asthenosphere mantle with a slight influence of slab-derived fluids.Therefore,we suggest that the formation of these Late Carboniferous dykes were triggered by a post-collisional slab breakoff and the Aqishan-Yamansu belt was a continental arc formed by southdipping subduction of the Kangguer oceanic plate. 展开更多
关键词 Central Asian orogenic belt Eastern Tianshan Adakitic Highly fractionated l-Type granite Slab breakoff
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Cerebellar artery infarction with sudden hearing loss and vertigo as initial symptoms: A case report 被引量:7
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作者 Xin-Lin Wang min sun Xiao-Ping Wang 《World Journal of Clinical Cases》 SCIE 2021年第11期2519-2523,共5页
BACKGROUND Sudden hearing loss(SHL)is associated with serious systematic conditions such as neoplasms,vascular events,autoimmune diseases,infections,and iatrogenic injury.Some authors report that SHL can be an early w... BACKGROUND Sudden hearing loss(SHL)is associated with serious systematic conditions such as neoplasms,vascular events,autoimmune diseases,infections,and iatrogenic injury.Some authors report that SHL can be an early warning sign of impending vertebrobasilar ischemic stroke.It is important to distinguish stroke from benign disease.CASE SUMMARY A 48-year-old male patient presented with SHL and vertigo as first symptoms.Diffusion-weighted imaging revealed high signal intensity in the left posterior inferior cerebellar artery territory of the cerebellar hemisphere and high signal intensity in the right pons and bridge cerebellar arm,confirming that the patient had cerebral infarction.Treatment with antiplatelet drugs,steroid antiinflammatory drugs,and neurotrophic nerve therapy promoted blood circulation and removed blood stasis,and the symptoms of the patient were significantly improved.CONCLUSION SHL and vertigo could be the initial symptoms of vertebrobasilar ischemic stroke. 展开更多
关键词 Sudden hearing loss VERTIGO Posterior inferior cerebellar artery Anterior inferior cerebellar artery Cerebral infarction Case report
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间戊二烯-马来酸酐(酰亚胺)序列调控聚合
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作者 刘坤 孙敏 +7 位作者 张凤 谢锋历 尹政 伍小娟 傅建松 佘正银 夏金魁 李安 《高分子材料科学与工程》 EI CAS CSCD 北大核心 2020年第11期25-34,共10页
马来酸酐(酰亚胺)交替共聚物种类繁多,但基于共轭二烯烃的交替共聚物报道极为罕见。文中从碳五馏分中的间戊二烯优化利用为背景,采用选择性溶剂萃取精馏方法获得高纯度(>99%)聚合级间戊二烯异构体,在此基础上利用经典自由基溶液聚合... 马来酸酐(酰亚胺)交替共聚物种类繁多,但基于共轭二烯烃的交替共聚物报道极为罕见。文中从碳五馏分中的间戊二烯优化利用为背景,采用选择性溶剂萃取精馏方法获得高纯度(>99%)聚合级间戊二烯异构体,在此基础上利用经典自由基溶液聚合方法,考察了间戊二烯异构体种类、引发剂类型、溶剂种类、共聚单体配比、温度等因素对间戊二烯-马来酸酐(酰亚胺)聚合动力学和微观结构的影响。实验结果表明,聚合行为符合严格交替共聚模式。进一步核磁分析结果表明此类序列调控聚合物序列种类依赖于共聚单体配比,可形成AB和AAB型序列共聚物。最后利用经典先成键后引发理论解释特殊交替共聚合现象。 展开更多
关键词 碳五馏分 萃取精馏 间戊二烯 自由基聚合 交替共聚物
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Metamorphism of the northern Liaoning Complex:Implications for the tectonic evolution of Neoarchean basement of the Eastern Block,North China Craton 被引量:14
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作者 Kam Kuen Wu Guochun Zhao +3 位作者 min sun Changqing Yin Yanhong He Pui Yuk Tam 《Geoscience Frontiers》 SCIE CAS CSCD 2013年第3期305-320,共16页
As one of the areas where typical late Archean crust is exposed in the Eastern Block of the North China Craton, the northern Laioning Complex consists principally of tonalitic-trondhjemitic-granodioritic (TTG) gneis... As one of the areas where typical late Archean crust is exposed in the Eastern Block of the North China Craton, the northern Laioning Complex consists principally of tonalitic-trondhjemitic-granodioritic (TTG) gneisses, massive granitoids and supracrustal rocks. The supracrustal rocks, named the Qingyuan Group, consist of interbedded amphibolite, hornblende granulite, biotite granulite and BIF. Petrological evidence indicates that the amphibolites experienced the early prograde (M1), peak (M2) and post-peak (M3) metamorphism. The early prograde assemblage (M1) is preserved as mineral inclusions, represented by actinotite + hornblende - plagioclase + epidote + quartz 4- sphene, within garnet porphyroblasts. The peak assemblage (M2) is indicated by garnet + clinopyroxene + hornblende + plagioclase + quartz + ilmenite, which occur as major mineral phases in the rock. The post-peak assemblage (M3) is characterized by the garnet 4- quartz symplectite. The P-T pseudosections in the NCFMASHTO system constructed by using THERMOCALC define the P-T conditions of M1, M2 and M3 at 490-550 C+(4.5 kbar, 780 810 C/7.65- 8.40 kbar and 630-670 +C]8.15-9.40 kbar, respectively. As a result, an anticlockwise P-T path involving isobaric cooling is inferred for the metamorphic evolution of the amphibolites. Such a P-T path suggests that the late Archean metamorphism of the northern Liaoning Complex was related to the intrusion and underplating of mantle-derived magmas. The underplating of voluminous mantle-derived magmas leading to metamorphism with an anticlockwise P-T path involving isobaric cooling may have occurred in continental magmatic arc regions, above hot spots driven by mantle plumes, or in continental rift envi- ronments. A mantle plume model is favored because this model can reasonably interpret many other geological features of late Archean basement rocks from the northern Liaoning Complex in the Eastern Block of the North China Craton as well as their anticlockwise P-T paths involving isobaric cooling. 展开更多
关键词 Amphibolites Northern Liaoning complex North China Craton Late Archean Metamorphic evolution
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Effect of berberine on hyperglycaemia and gut microbiota composition in type 2 diabetic Goto-Kakizaki rats 被引量:2
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作者 Jin-Dong Zhao Yan Li +10 位作者 min sun Chan-Juan Yu Jia-Yun Li Si-Hai Wang Di Yang Cheng-Lin Guo Xue Du Wen-Jin Zhang Ruo-Dong Cheng Xiao-Chuan Diao Zhao-Hui Fang 《World Journal of Gastroenterology》 SCIE CAS 2021年第8期708-724,共17页
BACKGROUND A recent investigation showed that the prevalence of type 2 diabetes mellitus(T2DM)is 12.8%among individuals of Han ethnicity.Gut microbiota has been reported to play a central role in T2DM.Goto-Kakizaki(GK... BACKGROUND A recent investigation showed that the prevalence of type 2 diabetes mellitus(T2DM)is 12.8%among individuals of Han ethnicity.Gut microbiota has been reported to play a central role in T2DM.Goto-Kakizaki(GK)rats show differences in gut microbiota compared to non-diabetic rats.Previous studies have indicated that berberine could be successfully used to manage T2DM.We sought to understand its hypoglycaemic effect and role in the regulation of the gut microbiota.AIM To determine whether berberine can regulate glucose metabolism in GK rats via the gut microbiota.METHODS GK rats were acclimatized for 1 wk.The GK rats were randomly divided into three groups and administered saline(Mo),metformin(Me),or berberine(Be).The observation time was 8 wk,and weight,fasting blood glucose(FBG),insulin,and glucagon-like peptide-1(GLP-1)were measured.Pancreatic tissue was observed for pathological changes.Additionally,we sequenced the 16S rRNA V3-V4 region of the gut microbiota and analysed the structure.RESULTS Compared with the Mo group,the Me and Be groups displayed significant differences in FBG(P<0.01)and GLP-1(P<0.05).A significant decrease in weight and homeostatic model assessment-insulin resistance was noted in the Be group compared with those in the Me group(P<0.01).The pancreatic islets of the Me-and Be-treated rats showed improvement in number,shape,and necrosis compared with those of Mo-treated rats.A total of 580 operational taxonomic units were obtained in the three groups.Compared to the Mo group,the Me and Be groups showed a shift in the structure of the gut microbiota.Correlation analysis indicated that FBG was strongly positively correlated with Clostridia_UCG-014(P<0.01)and negatively correlated with Allobaculum(P<0.01).Body weight showed a positive correlation with Desulfovibrionaceae(P<0.01)and a negative correlation with Akkermansia(P<0.01).Importantly,our results demonstrated that Me and Be could significantly decrease Bacteroidetes(P<0.01)and the Bacteroidetes/Firmicutes ratio(P<0.01).Furthermore,Muribaculaceae(P<0.01;P<0.05)was significantly decreased in the Me and Be groups,and Allobaculum(P<0.01)was significantly increased.CONCLUSION Berberine has a substantial effect in improving metabolic parameters and modulating the gut microbiota composition in T2DM rats. 展开更多
关键词 Type 2 diabetes mellitus Amelioration of hyperglycaemia Modulation of gut microbiota BERBERINE METFORMIN Goto-Kakizaki rats
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