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Journal of Mountain Science 2017年第4期14卷 611-620页

作者： chen ning-sheng zhu yun-hua huang Qi IQBAL Javed DENG Ming-feng HE Na Key Laboratory of Mountain Hazards and Surface Process Institute of Mountain Hazards and EnvironmentChinese Academy of Sciences and Ministry of Water ResourcesChengdu 610041China University of Chinese Academy of Sciences Beijing 100049China Southwest Petroleum University Chengdu 610500China Southwest Electric Power Design Institute CO LTDChengdu 610021China Department of Earth Sciences COMSATS Institute of Information Technology22060 AbbottabadPakistan

The triggering mechanisms of debris flows were explored in the field using artificial rainfall experiments in two gullies, Dawazi Gully and Aizi Gully, in yunnan and Sichuan Provinces, China,respectively. The soils at both sites are bare, loose and cohesive gravel-dominated. The results of a direct shear test, rheological test and back-analysis using soil mass stability calculations indicate that the mechanisms responsible for triggering debris flows involved the decreases in static and dynamic resistance of the soil. The triggering processes can be divided into 7 stages: rainfall infiltration, generation of excess runoff, high pore water pressure, surface erosion, soil creep, soil slipping, debris flow triggering and debris flow increment. In addition, two critical steps are evident:(i) During the process of the soil mass changing from a static to a mobile state, its cohesion decreased sharply(e.g., the cohesion of the soil mass in Dawazi Gully decreased from 0.520 to0.090 k Pa, a decrease of 83%). This would have reduced the soil strength and the kinetic energy during slipping, eventually triggered the debris flow.(ii) When the soil mass began to slip, the velocity and the volume increment of the debris flow fluctuated as a result of the interaction of soil resistance and the sliding force. The displaced soil mass from the source area of the slope resulted in the deposition of a volume of soil more than 7-8 times greater than that in the source area.

关键词： Debris flow Cohesive gravel soil Triggering mechanism Slip Soil erosion

Two new steroidal saponins isolated from Anemarrhena asphodeloides

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Chinese Journal of Natural Medicines 2017年第3期15卷 220-224页

作者： SUN Xing-Huan zhu Fu-Tao ZHANG Yu-Wei chen Fang-Fang YU yun SONG ning-ning huang Xue-feng State Key Laboratory of Natural Medicines Department of Natural Medicinal ChemistryChina Pharmaceutical UniversityNanjing 210009China

Two new steroidal saponins,named timosaponin P(1) and timosaponin Q(2),were isolated from the rhizome parts of Anemarrhena asphodeloides Bunge using various chromatographic *** structures and absolute configurations were elucidated by a combination of spectroscopic and spectrometric data,including 1D,2D NMR,HR-ESI-MS and ECD calculations,and this is the first time the absolute configuration of C-23 of steroidal saponin was confirmed by ECD calculations.

关键词： Anemarrhena asphodeloides Timosaponin P Timosaponin Q ECD Steroidal saponin Absolute configuration

Characteristic response of striatal astrocytes to dopamine depletion

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Neural Regeneration Research 2020年第4期15卷 724-730页

作者： Yao-feng zhu Wei-Ping wang Xue-feng Zheng Zhi chen Tao chen Zi-yun huang Lin-Ju Jia Wan-Long Lei Department of Anatomy Zhongshan School of MedicineSun Yat-sen UniversityGuangzhouGuangdong ProvinceChina Institute of Medicine College of MedicineJishou UniversityJishouHunan ProvinceChina Periodical Center the Third Affiliated HospitalSun Yat-sen UniversityGuangzhouGuangdong ProvinceChina

Astrocytes and astrocyte-related proteins play important roles in maintaining normal brain function,and also regulate pathological processes in brain diseases and ***,the role of astrocytes in the dopamine-depleted striatum remains unclear.A rat model of Parkinson’s disease was therefore established by injecting 10μL 6-hydroxydopamine(2.5μg/μL)into the right medial forebrain *** staining was used to detect the immunoreactivity of glial fibrillary acidic protein(GFAP),calcium-binding protein B(S100B),and signal transducer and activator of transcription 3(STAT3)in the striatum,and to investigate the co-expression of GFAP with S100B and *** blot assay was used to measure the protein expression of GFAP,S100B,and STAT3 in the *** demonstrated that striatal GFAP-immunoreactive cells had an astrocytic appearance under normal conditions,but that dopamine depletion induced a reactive phenotype with obvious morphological *** normal striatum also contained S100B and STAT3 expression.S100B-immunoreactive cells were uniform in the striatum,with round bodies and sparse,thin ***3-immunoreactive cells presented round cell bodies with sparse processes,or were darkly stained with a large cell *** deprivation induced by 6-hydroxydopamine significantly enhanced the immunohistochemical positive reaction of S100B and *** striatal astrocytes expressed both S100B and *** dopamine deprivation increased the number of GFAP/S100B and GFAP/STAT3 double-labeled cells,and increased the protein levels of GFAP,S100B,and *** present results suggest that morphological changes in astrocytes and changes in expression levels of astrocyte-related proteins are involved in the pathological process of striatal dopamine *** study was approved by Animal Care and Use Committee of Sun Yat-sen University,China(Zhongshan Medical Ethics 2014 No.23)on September 22,2014.

关键词： 6-hydroxydopamine astrocyte dopamine depletion dopaminergic neurons Parkinson’s disease SIOOB STAT3 striatum

Trends of Temperature Extremes in Summer and Winter during 1971–2013 in China

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Atmospheric and Oceanic Science Letters 2015年第4期8卷 220-225页

作者： huang ling chen Ai-Fang zhu yun-Hua wang Hong-Lin HE Bin College of Global Change and Earth System Science Beijing Normal University College of Business Administration Huaqiao University

The diurnal temperature range(DTR) has decreased dramatically in recent decades, but it is not yet obvious whether the extreme values of DTR have also reduced. Based on the daily maximum and minimum temperature data of 653 stations in China, a set of monthly indices of warm extremes, cold extremes, and DTR extremes in summer(June, July, August) and winter(December, January, February) were studied for spatial and temporal features during the period 1971–2013. Results show that the incidence of warm extremes has been increasing in most parts of China, while the opposite trend was found in the cold extremes for summer and winter months. Both increasing and decreasing trends of monthly DTR extremes were identified in China for both seasons. For high DTR extremes, decreasing trends were identified in northern China for both seasons, but increasing trends were found only in southern China in summer, while in winter, they were found in central China. Monthly low DTR extreme indices demonstrated consistent positive trends in summer and winter, while significant increases(P < 0.05) were identified for only a few stations.

关键词： temperature extremes diurnal temperature range temperature trend spatial and temporal features China

Active oxygen species and oxidation mechanism over Ce-doped LaMn_(0.8)Ni_(0.2)O_(3)/hierarchical ZSM-5 in pentanal oxidation

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Journal of Rare Earths 2021年第9期39卷 1062-1072页

作者： Jian Li Yingjie Shi Xiaoheng Fu yun Shu jiayu huang Jinwei zhu Gang Tian Jingnan Hu Research Center of Air Pollution Control Technology Chinese Research Academy of Environmental SciencesBeijing 100012China School of Chemical and Environmental Engineering China University of Mining and Technology(Beijing)Beijing 100083China

Hierarchical ZSM-5(HZ)molecular sieves based on fly ash were synthesized using a method combining water heat treatment with step-by-step *** coupling catalysts between La_(1-x)Ce_(x)Mn_(0.8)-Ni_(0.2)O_(3)(x≤0.5)perovskites and HZ were prepared through the impregnation method,which were characterized by X-ray diffraction(XRD),scanning electron microscopy(SEM),high-resolution transmission electron microscopy(HRTEM),N_(2)adsorption,X-ray photoelectron spectroscopy(XPS),NH3-temperature programmed desoprtion(NH3-TPD),H_(2)-temperature programmed reduction(H_(2)-TPR)and O_(2)-TPD techniques and investigated regarding pentanal oxidation at 120-390℃to explore the effects of Ce doping on the catalytic activity and the active oxygen species of the coupling catalysts,meanwhile,the reaction mechanism and pathway of pentanal oxidation were also *** results reveal that Ce substitution at La sites can change the electronic interactions between all the elements and promote the electronic transfer among La,Ce,Ni,Mn and HZ,influencing directly the physicochemical characteristics of the ***,the amount and transfer ability of surface adsorbed oxygen(O_(2)-and O-)regarded as the reactive oxygen species and the low temperature reducibility are the main influence factors in pentanal ***,La_(0.8)Ce_(0.2)Mn_(0.8)Ni_(0.2)O_(3)/HZ exhibits the best catalytic activity and deep oxidation capacity as well as a better water resistance due to its larger amount of surface adsorbed oxygen species and higher low temperature ***’s more,appropriate Ce substitution can significantly enhance the amount of O_(2)-ions,which can distinctly enhance the catalytic activity of the catalyst,and moderate acid strength and appropriate acid amount can also facilitate the improvement of the pentanal oxidation *** is found that there is a synergic catalytic effect between surface acidity and redox ability of the *** to the in s

关键词： Hierarchical ZSM-5 molecular sieve Catalytic oxidation Active oxygen species Perovskite Ce doping Rare earths

Free-Fall Penetration Behaviors of A New Dynamically Installed Plate Anchor in Marine Clay

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China Ocean Engineering 2020年第6期34卷 795-805页

作者： LAI Ying huang yun-han chen Chuan zhu Bin MOE Key Laboratory of Soft Soils and Geoenvironmental Engineering College of Civil Engineering and ArchitectureZhejiang UniversityHangzhou 310058China College of Civil and Harbour Engineering Jiangsu Ocean UniversityLianyungang 222005China

A new dynamically installed plate anchor, the Flying Wing Anchor~?, has been developed as a sustainable anchor concept for deep-water offshore wind turbines. The anchor is firstly installed by free-fall penetration and then followed by drag embedment. If the anchor is subjected to environmental loads, it dives deeper to mobilize a higher capacity. This study presents a series of free-fall penetration tests with model anchors in different weights to assess the anchor behavior during the free-fall penetration performance in one-layer soil with a constant shear strength profile. Anchor velocities and embedment depths were measured by a magnetometer. An energy-based model and a force-based model were calibrated against the test results of model anchors with different weights. Based on the calibrated force-based model, a series of design charts were developed to estimate the embedment depth of anchors in different sizes and with different impact velocities in various marine clays. The framework to plot design charts presented herein can be potentially applied to other dynamically installed anchors to predict embedment depth in engineering practice.

关键词： dynamic anchor dynamic installation plate anchor scale effect design chart

Dynamic Installation Behaviors of A New Hybrid Plate Anchor in Layered Marine Clay

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China Ocean Engineering 2021年第5期35卷 736-749页

作者： LAI Ying zhu Bin chen Chuan huang yun-han MOE Key Laboratory of Soft Soils and Geoenvironmental Engineering College of Civil Engineering and ArchitectureZhejiang UniversityHangzhou 310058China Jiangsu Ocean University Lianyungang 222005China

Layered soil profiles create challenges for foundation installation and detrimentally affect the foundation *** research explored the free-fall penetration behavior of a new dynamically installed plate anchor,the Flying Wing Anchor?,in layered soil *** new concept anchor combines the advantages of low-cost installation of torpedo piles and high efficiency of plate *** is initially installed through free-fall like a torpedo pile,and followed by drag embedment like a plate *** methodology is to perform free-fall penetration tests with a model anchor in a variety of test beds containing marine clays with different profiles of undrained shear strength versus depth.A calibrated prediction model accounting for the effects of strain-rate and stiff layer produces results similar to those from the model *** design curves were developed based on the calibrated analytical model,and are valuable to estimate the impact velocity thresholds of prototype anchor to penetrate through stiff *** free-fall penetration tests indicated that the penetration ability of FWA?increases with the increased impact *** new dynamically embedded plate anchor can penetrate through the stiff layers that would cause problems for the conventional plate anchor,such as the drag embedded anchor,plowing on the top of stiff layer instead of breaking into ***,the new dynamically embedded plate anchor can provide a possible solution for layered soil profiles in deep water.

关键词： layered soils penetration hybrid anchors dynamically installed anchors plate anchors

Preparation of Nb_(3)Al powder by chemical reaction in molten salts

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Rare Metals 2022年第5期41卷 1671-1676页

作者： Na wang Cai-yun huang Yao Zhang Hong-Min zhu School of Materials Science and Engineering Beijing University of TechnologyBeijing 100024China School of Metallurgical and Ecological Engineering University of Science and Technology BeijingBeijing 100083China Tangshan Iron and Steel International Engineering Technology Co. LtdTangshan 063000China

Nb_(3)Al nanoparticles were directly synthesized by metallothermic reduction process in the molten salts with mNbCl_(5)-nAlCl_(3) powders as raw materials and sodium as reducing reagent. The effects of different feeding material orders, soaking time, Nb content in raw materials, and 3NbCl_(5)-AlCl_(3) content in molten salts on the obtained Nb_(3)Al powder were discussed. The as-prepared samples were characterized by X-ray diffraction(XRD), scanning electron microscopy(SEM), and transmission electron microscopy(TEM). It is found that the only phase Nb_(3)Al nanoparticles are obtained by controlling the variation of the feeding material orders, soaking time, and Nb content in raw materials. And the morphologies of as-prepared nanoparticles change owning to different 3NbCl_(5)-AlCl_(3) contents in molten salts.

关键词： Chemical reaction Nb3Al nanoparticles Feeding material orders Molten salt

Southwest Boundary of Yangtze and Cathaysia Blocks:Constraints from the Luojiashan Gabbro in Yingyangguan Region,Northeastern Guangxi

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Journal of Earth Science 2024年第5期35卷 1447-1463页

作者： Ya Qin Zuohai feng Jiaming zhu Yonggao huang Jie Wu yun Zhou yunfeng Xue Chunzeng wang Collaborative Innovation Center for Exploration of Nonferrous Metal Deposits and Eficient Utilization of Resources by the Province and Ministry Guilin University of TechnologyGuilin 541004China Jiangsu Tuojia Engineering Design and Research Co. Ltd.Nanjing 211100China China Chemical Geology and Mine Bureau Henan Branch Zhengzhou 450000China University of Maine at Presque Isle Presque IsleMaine 04769USA

The Luojiashan gabbro is a newly discovered mafic pluton emplaced in the Neoproterozoic Yingyangguan Formation in Yingyangguan region of northeastern Guangxi,South *** whole-rock geochemical and zircon geochronological and Hf isotopic analyses are performed on the gabbro and comparisons are made with the coeval mafic-ultramafic sills and dikes located in Longsheng region of northern Guangxi in order to understand the magmatic origin,evolution,and tectonic setting of the Luojiashan gabbro and to address the location of the suture zone of the Southwestern Jiangnan Orogen(SJO).LA-ICP-MS zircon U-Pb ages obtained from the Luojiashan gabbro show that it was emplaced at~770 *** gabbro contains abundant inherited zircons aged at 0.9-1.3 Ga,consistent with age spectrum of the Cathaysia ***-normalized REE pattern,primitive mantle-normalized trace element spider diagram,incompatible element ratios of Nb/Ta,Zr/Hf,La/Nb,Ba/Th,Th/La,and Ba/La,and Th/Yb-Ta/Yb discrimination diagram of the gabbro are indicative of OIB-like geochemical characteristics and of derivation from partially melted garnet peridotite of the asthenospheric *** discrimination based on the trace and rare earth elements also indicate that the Luojiashan gabbro was emplaced in a within-plate extensional rift setting,probably as a result of Rodinia supercontinent dismantling,lithospheric thinning,and underplating and upwelling of the asthenospheric *** on zircon age,Hf isotopic data and comparison between northern and northeastern Guangxi,it is suggested that the Yingyangguan region was tectonically situated in a different tectonic locale from the Longsheng region of northern Guangxi at about 770 Ma during the post-orogenic mafic-ultramafic magmatic event,with the former within the Cathaysia Block and the latter along the southeast margin of Yangtze *** suture between the Yangtze and Cathaysia blocks must be located between Yingyangguan of northeastern Gua

关键词： geochronology inherited zircon Luojiashan gabbro suture Yingyangguan tectonic