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Petrogenesis and Tectonic Implications of the Late Silurian–Early Devonian Bimodal Intrusive Rocks in the Central Beishan Orogenic Belt,NW China:Constraints by Petrology,Geochemistry and Hf Isotope

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Journal of Earth Science 2023年第2期34卷 431-443页

作者： Jian Tian Hou-Tian Xin Xue-Jian Teng Min Li Qun-An Liao Yong Zhang bang-fang ren Tianjin Center China Geological SurveyTianjin 300170China Shenyang Center China Geological SurveyShenyang 110086China School of Earth Sciences China University of GeosciencesWuhan 430074China

A large number of Late Silurian–Early Devonian intrusive rocks are distributed in the central Beishan orogenic belt(BOB).Tectonic setting of these intrusive rocks is of great significance to the study of the subduction and accretion of the Paleo-Asian *** studies show that most of the intrusive rocks in this region are S-type or A-type *** this study,we firstly reported the Late Silurian–Early Devoniandia bases,granodiorites on the southside of the Baiyunshan ophiolitic mélanges belt,as a part of Hongliuhe-Xichangjing ophiolitic mélanges belt(HXOMB).Zircon LA-ICP-MS U-Pb dating yields emplacement ages between 418 and 397 Ma,REE distribution patterns exhibit enriched LREE and flat HREE in the diabases,the discriminant diagrams show that the diabases have geochemical characteristics of intraplate *** granodiorites in this paper present more like S-and A-type granitoids reported,showing the geochemical characteristics of syn/post-collision ***,the bimodal magmatic rocks are developed during Late Silurian–Early Devonian on both sides of the HXOMB,which are related to the tectonic background of the post orogeny *** diabases are tholeiitic with relative strong depletedεHf(t)(+8.1 to+13.0),which are mainly from relative depleted *** granodiorites are calc-alkaline with relative slightly depletedεHf(t)(+0.7 to+5.6)and the lower Mg#and MgO contents(34.6–36.9,0.50 wt.%–1.19 wt.%respectively),reflecting the source characteristics of ***,the remelting of juvenile crust may be the main way of continental crust accretion during Late Silurian–Early Devonian in the central BOB.

关键词： Beishan orogenic belt ophiolitic mélanges belt Late Silurian–Early Devonian bimodal intrusive rocks extension geochemistry

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Petrology,Zircon Chronology and Geochemistry of the Late Silurian Ophiolitic Mélanges and the Baiyunshan Forearc Complex in the Central Beishan Orogenic Belt,NE China

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Journal of Earth Science 2023年第2期34卷 444-455页

作者： Hou-Tian Xin Jian Tian Xue-Jian Teng Li-Xin Sun Guo-Zhen Zhang Yong Zhang bang-fang ren Shenyang Center China Geological SurveyShenyang 110086China Tianjin Center China Geological SurveyTianjin 300170China

The WNW-ESE-trending Baiyunshan ophiolitic mélange is exposed in the central Beishan orogenic belt(BOB),between the Hongliuhe-Niujuanzi and Xichangjing ophiolitic mélanges in the west and east,*** we present new petrological,geochemical,and zircon U-Pb age data for the Baiyunshan ophiolitic mélange and metamorphosed lithic sandstones of“the Baiyunshan Formation”.The Baiyunshan ophiolitic mélange is characterized by a block-in-matrix structure,and the blocks of ultramafic-mafic rocks are mainly pyroxenites,dunites,gabbros,and minor *** U-Pb dating yielded an emplacement age of 424.2±3.7 Ma for the *** ultramaficmafic rocks have geochemical features of supra-subduction zone-type ophiolites,including low Ti contents(TiO2=0.01 wt.%–0.35 wt.%),negative Nb-Ta anomalies,and U-shaped rare earth element patterns with positive Eu anomalies(δEu=0.99–3.25).“The Baiyunshan Formation”is exposed to the north of the ophiolitic mélange,and comprises mainly meta-cherts in its lower part and metasandstones and marbles in its upper *** of basalt are locally dispersed in the sand-slate *** ages of detrital zircons in the metamorphosed lithic sandstones range from 521 to 464 Ma,with an age peak of 500 Ma,which is similar to those of the Gongpoquan arc in the *** central Beishan orogenic belt experienced continuous subduction of the Hongliuhe-Xichangjing oceanic lithosphere in the Late Silurian,which produced the Baiyunshan forearc complex and supra-subduction zone-type ophiolite.

关键词： Beishan orogenic belt the Hongliuhe-Xichangjing Ocean the ultramafic-mafic rocks Late Silurian SSZ-type ophiolite Subduction and accretion geochemistry

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Capturability-based Fuzzy Footstep Planner for a Biped Robot with Centroidal Compliance

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Journal of Bionic Engineering 2024年第1期21卷 84-100页

作者： Zihan Xu Qin fang Yong ren Chengju Liu Robot and Artificial Intelligence Lab(RAIL) College of Electronic and Information EngineeringTongji UniversityShanghai 201804China Applied Technology College Soochow UniversitySuzhou 215000China

Compliance motion and footstep adjustment are active balance control strategies from learning human subconscious *** force estimation without direct end-actuator force measurement and the optimal footsteps based on complex analytical calculation are still challenging tasks for elementary and kid-size position-controlled *** this paper,an online compliant controller with Gravity Projection Observer(GPO),which can express the external force condition of perturbations by the estimated Projection of Gravity(PoG)with estimation covariance,is proposed for the realization of disturbance absorption,with which the robustness of the humanoid contact with environments can be *** fuzzy footstep planner based on capturability analysis is proposed,and the Model Predictive Control(MPC)is applied to generate the desired *** fuzzification rules are well-designed and give the corresponding control output responding to complex and changeable external *** validate the presented methods,a series of experiments on a real humanoid robot are *** results verify the effectiveness of the proposed balance control framework.

关键词： Biped walking Centroidal compliance Gravity projection observer Fuzzy footstep planner

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An axisymmetric characteristic model for enhancing prediction of centrifugal compressor characteristics

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Chinese Journal of Aeronautics 2024年第4期37卷 203-215页

作者： Peng ren Xiangjun fang Zeyu JIAO Ying HAN School of Energy and Power Engineering Beihang UniversityBeijing 100191China Guangdong Key Laboratory of Modern Control Technology Institute of Intelligent ManufacturingGuangdong Academy of SciencesGuangzhou 510070China

Rapid and accurate determination of compressor characteristic maps is essential for the initial design of centrifugal compressors in aircraft power systems. The accuracy of existing methodologies, which rely on combinations of loss models, varies significantly depending on the compressor's geometry and operational range. This variance necessitates substantial experimental or Computational Fluid Dynamics(CFD) data for coefficient calibration. To address this challenge, this study presents an axisymmetric characteristic model for compressor performance assessment. This model incorporates the factors of blade angle, meridional passage area, and the radial deflection angle of meridional streamlines of the compressor. These factors are derived from fundamental aerodynamic equations encompassing mass, momentum, and energy conservation of the compressor. In contrast to conventional one-dimensional approaches, the proposed method reduces the number of loss coefficients and more effectively accounts for the impact of geometric alterations on centrifugal compressor properties. Furthermore, the model reduces dependence on experimental and CFD data. Efficacy of the model is validated using experimental data from four distinct types of centrifugal compressors. Correlation analysis reveals that the model's coefficients can be expressed as functions of the ratio of the Reynolds number to the impeller tip speed. This ratio serves as a characteristic parameter for the design and optimization of centrifugal compressors. Consequently, the proposed method offers an efficient and accurate means for the quick computation of centrifugal compressor characteristics. This is of great significance for improving the efficiency of centrifugal compressors and reducing energy consumption.

关键词： Centrifugal compressor Positive problem Characteristic prediction Aerodynamic characteristic Axisymmetric model

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Modelling analysis embodies drastic transition among global potential natural vegetations in face of changing climate

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Forest Ecosystems 2024年第2期11卷 184-192页

作者： Zhengchao ren Lei Liu fang Yin Xiaoni Liu School of Earth Science and Resources Chang’an UniversityXi’an710054China Research Center of Ecological Construction and Environmental Conservation in Gansu Province Gansu Agricultural UniversityLanzhou730070China State Key Laboratory of Tibetan Plateau Earth System Environment and Resources(TPESER)Institute of Tibetan Plateau ResearchChinese Academy of SciencesBeijing100101China School of Land Engineering Chang’an UniversityXi’an710054China College of Pratacultural Science Gansu Agricultural UniversityLanzhou730070China

Potential natural vegetation(PNV)is a valuable reference for ecosystem renovation and has garnered increasing attention ***,there is limited knowledge on the spatio-temporal distributions,transitional processes,and underlying mechanisms of global natural vegetation,particularly in the case of ongoing climate *** this study,we visualize the spatio-temporal pattern and inter-transition procedure of global PNV,analyse the shifting distances and directions of global PNV under the influence of climatic disturbance,and explore the mechanisms of global PNV in response to temperature and precipitation *** achieve this,we utilize meteorological data,mainly temperature and precipitation,from six phases:the Last Inter-Glacial(LIG),the Last Glacial Maximum(LGM),the Mid Holocene(MH),the Present Day(PD),2030(20212040)and 2090(2081–2100),and employ a widely-accepted comprehensive and sequential classification sy–stem(CSCS)for global PNV *** find that the spatial patterns of five PNV groups(forest,shrubland,savanna,grassland and tundra)generally align with their respective ecotopes,although their distributions have shifted due to fluctuating temperature and ***,we observe an unexpected transition between tundra and savanna despite their geographical *** shifts in distance and direction of five PNV groups are mainly driven by temperature and precipitation,although there is heterogeneity among these shifts for each ***,the heterogeneity observed among different global PNV groups suggests that they may possess varying capacities to adjust to and withstand the impacts of changing *** spatio-temporal distributions,mutual transitions and shift tendencies of global PNV and its underlying mechanism in face of changing climate,as revealed in this study,can significantly contribute to the development of strategies for mitigating warming and promoting re-vegetation in degraded regions worldwide.

关键词： Potential natural vegetation Global warming Vegetation classification Predicted model CSCS

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Secure state estimation for cyber-physical systems with unknown input sliding mode observer

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Control Theory and Technology 2024年第2期22卷 244-253页

作者： Panpan Zhang Yuwei ren Yixian fang Ang Liu School of Information Science and Engineering Shandong Normal UniversityJinan250358ShandongChina School of Information Engineering Shandong Management UniversityJinan250357ShandongChina

In recent years, cyber attacks have posed great challenges to the development of cyber-physical systems. It is of great significance to study secure state estimation methods to ensure the safe and stable operation of the system. This paper proposes a secure state estimation for multi-input and multi-output continuous-time linear cyber-physical systems with sparse actuator and sensor attacks. First, for sparse sensor attacks, we propose an adaptive switching mechanism to mitigate the impact of sparse sensor attacks by filtering out their attack modes. Second, an unknown input sliding mode observer is designed to not only observe the system states, sensor attack signals, and measurement noise present in the system but also counteract the effects of sparse actuator attacks through an unknown input matrix. Finally, for the design of an unknown input sliding mode state observer, the feasibility of the observing system is demonstrated by means of Lyapunov functions. Additionally, simulation experiments are conducted to show the effectiveness of this method.

关键词： Sparse attacks Cyber-physical systems Unknown input sliding mode Secure state estimation Adaptive switching mechanism

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Electroacupuncture Promotes Angiogenesis in Mice with Cerebral Ischemia by Inhibiting miR-7

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Chinese Journal of Integrative Medicine 2024年第6期30卷 543-550页

作者： YU Qian SHU Shi JU Xin-yao PENG Wei ren Xue-qi SI Shu-han SONG Shi-zhen XIE Xue-yun fang bang-jiang ZHOU Shuang School of Acupuncture-Moxibustion and Tuina Shanghai University of Traditional Chinese MedicineShanghai201203China College of Basic Medicine Shanghai University of Traditional Chinese MedicineShanghai201203China Department of Emergency Longhua HospitalShanghai University of Traditional Chinese MedicineShanghai200032China

Objective To observe the angiogenesis effect of electroacupuncture(EA)at Shuigou acupoint(GV 26)in the treatment of cerebral ischemia,and explore the value of miRNA-7(miR-7)in *** First,48 mice were randomly divided into sham operation,middle cerebral artery occlusion(MCAO)model,and EA treatment *** 9 mice were divided into carrier control group,miR-7 knockout group and miR-7 overexpression group(n=3 each group).Finally,20 mice were divided into model and carrier control group,model and miR-7 knockout group,EA treatment and carrier control group and EA treatment and miR-7 overexpression group,with 3–6 mice in each *** MCAO model was established in the MCAO and EA *** deficit score and 2,3,5-triphenyltetrazolium chloride(TTC)staining were used to evaluate the severity of cerebral ***-eosin staining was used to describe basic pathological *** was used to quantify cerebral microvessel ***-time PCR and Western blot were used to detect the expression of miR-7 and its downstream target genes Krüppel-like factor 4/vascular endothelial growth factor(KLF4/VEGF)and angiopoietin-2(ANG-2)in the ischemic cerebral *** After EA,neurological deficit scores and infarction volumes decreased,and the density of cerebral microvessels *** the MCAO group,miR-7 expression was higher than that in the sham group(P<0.01).After EA at GV 26,miR-7 expression decreased(P<0.01)and the expression of downstream target genes KLF4/VEGF and ANG-2 increased as compared with the MCAO group(P<0.01).After EA combined with overexpression of miR-7,the expression of downstream target genes KLF4/VEGF and ANG-2 decreased compared to the control EA group(P<0.01).After miR-7 knockdown,the expression of KLF4/VEGF and ANG-2 increased(P<0.05 or P<0.01).Conclusions EA could promote angiogenesis in MCAO mice likely by inhibiting the expression of miR-7 and relieving inhibition of downstream target genes KLF4/VEG

关键词： electroacupuncture cerebral ischemia miRNA-7 angiogenesis Shuigou(GV 26) acupuncture points

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Observing eddy dye patches induced by shear instabilities in the surf zone on a plane beach

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Acta Oceanologica Sinica 2024年第3期43卷 15-29页

作者： Chunping ren Nannan Fu Chong Yu Yuchuan Bai Kezhao fang State Key Laboratory of Hydraulic Engineering Simulation and Safety Tianjin UniversityTianjin 300072China College of Water Resource Science and Engineering Taiyuan University of TechnologyTaiyuan 030024China State Key Laboratory of Coastal and Offshore Engineering Dalian University of TechnologyDalian 116024China

The effects of surf zone eddy generated by alongshore currents on the deformation and transport of dye are still poorly understood,and related tracer release experiments are ***,a tracer release laboratory experiment was conducted under monochromatic,unidirectional incident waves with a large incident angle(30°)on a plane beach with a 1:100 slope in a large wave basin.A charge-coupled device suspended above the basin recorded the dye patch *** evolution of eddy dye patch was observed and the transport and diffusion were analyzed based on the collected ***,a linear instability numerical model was adopted to calculate the perturbation velocity field at the initial *** observation and image processing results show that surf zone eddy patches occurred and were separated from the original dye *** numerical analysis results demonstrate that the structure of the perturbation velocity field is consistent with the experimental observations,and that the ejection of eddy patches shoreward or offshore may be ascribed to the double vortex.

关键词： surf zone tracer release experiment evolution of eddy patch shear instability of alongshore currents

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Influence of Mixture Gas Conditions on the Laminar Combustion Characteristics of Natural Gas

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Journal of Thermal Science 2024年第3期33卷 1231-1241页

作者： LOU Diming ZHU Kan ZHANG Yunhua ren Yedi TAN Piqiang fang Liang FAN Lanlan School of Automotive Studies Tongji UniversityShanghai201804China Ji’nan Power Co.Ltd Sinotruk GroupJi’nan250200China

Natural gas is a promising alternative fuel for the internal combustion engine,and natural gas engine has become an efficient and feasible measure to deal with the energy shortage and climate *** the laminar flame characteristics are the foundation of the turbulent flame,the laminar flame characteristics of natural gas have a significant impact on the combustion status and efficiency of the engine.A visual constant volume bomb was used to study the influence of the gas components,different excess air coefficient(λ),and initial conditions on the laminar combustion characteristics of natural *** experimental results showed that when the initial pressure and temperature were 0.1 MPa and 300 K respectively,compared to propane,ethane had a remarkable influence on the equivalent-combustion laminar-combustion-speed,with an average increase of approximately 5.1%for every 2.5%increase in the ethane *** laminar combustion velocity of the natural gas under different excess air coefficients had a maximum value at aboutλ=1.0,and the Markstein length of the flame decreased with the increase of theλ.The increase in the initial pressure of the mixture resulted in a decrease in the equivalent-combustion laminar-combustion-speed of the flame,a significant decrease in the Markstein *** increase of the initial temperature of the mixture led to a rapid increase of the equivalent-combustion laminar-combustion-speed,but the effect on the flame Markstein length was not dominant.

关键词： constant volume bomb natural gas engine combustion characteristics laminar combustion velocity Markstein length

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Fecal microbiota transplantation:whole grain highland barley improves glucose metabolism by changing gut microbiota

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Food Science and Human Wellness 2024年第4期13卷 2014-2024页

作者： Xin ren Fulong Zhang Min Zhang Yuan fang Zenglong Chen Meili Huan Beijing Advanced Innovation Center for Food Nutrition and Human Health Beijing Engineering and Technology Research Center of Food AdditivesNational Grain Industry Highland Barley Deep Processing Technology Innovation CenterBeijing Technology and Business UniversityBeijing 100048China State Key Laboratory of Integrated Management of Pest Insects and Rodents Institute of ZoologyChinese Academy of SciencesBeijing 100101China COFCO Nutrition and Health Research Institute Beijing 102209China

Highland barley(HB)is a high-altitude cereal with rich nutritional components and potential health *** clarify its hypoglycemic effect and mechanism,we investigated the effect of whole grain HB and fecal microbiota transplantation(FMT)on glucose metabolism and gut microbiota in high-fat diet and streptozotocin(HFD/STZ)-induced diabetic *** results showed that HB(40%)significantly decreased fasting blood glucose and the area under the glucose tolerance curve,significantly increased insulin secretion and improved insulin resistance in HFD/STZ-induced diabetic mice(P<0.05).Inflammatory factors and blood lipid indices were also significantly alleviated after 12 weeks of 40%HB intervention(P<0.05).Additionally,beneficial bacteria,such as Bifidobacterium and Akkermansia,were significantly enriched in the gut of diabetic mice after whole grain HB ***,the results of further FMT experiments verified that the fecal microbiota after the 40%HB intervention not only significantly increased the relative abundance of Bifidobacterium and Akkermansia but also effectively improved glucose metabolism and alleviated the inflammatory state in HFD/STZ-induced diabetic ***,our study confirmed the bridge role of gut microbiota in improving glucose metabolism of whole grain HB,which could promote the development of precision nutrition.

关键词： Highland barley Diabetes Glucose metabolism Gut microbiota Fecal bacteria transplantation

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