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Determination of rill erodibility and critical shear stress of saturated purple soil slopes

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International Soil and Water Conservation Research 2022年第1期10卷 38-45页

作者： Dandan Li Xiaoyan Chen Zhen Han xiaojie gu Yanhai Li College of Resources and Environment/Key Laboratory of Eco-environment in Three Gorges Region(Ministry of Education) Southwest UniversityChongqing400716China College of Forest.guizhou University GuiyangGuizhou Province550000China

The hydrological conditions near the soil surface influence the soil erosion process,as determined by the soil erodibility and critical shear *** soil erodibility and critical shear stress of saturated purple soil slopes were computed and compared with those of unsaturated purple soil *** detachment capacities computed through the numerical method(NM),modified numerical method(MNM)and analytical method(AM),from rill erosion experiments on saturated purple soil slopes at different flow rates(2,4,and 8 L min-1)and slope gradients(5,10,15,and 20°),were used to comparatively compute the soil erodibility and critical shear *** computed soil erodibilities and critical shear stresses were also compared with those of unsaturated purple soil *** the different slope gradients ranging from 5°to 20°,there were no significant differences in the soil erodibilities of the saturated purple soil and also in those of the unsaturated purple *** critical shear stresses slightly varied with the slope *** saturated purple soil was relatively significantly more susceptible to *** NM overestimated the soil erodibility of both saturated and unsaturated soils by 31%and underestimated the critical shear *** MNM yielded the same soil erodibility and critical shear stress values as the *** results of this study supply parameters for modeling rill erosion of saturated purple soil slope.

关键词： Critical shear stress Erodibility Detachment capacity Rill erosion Saturated purple soil

Chemical and biological research of Clematis medicinal resources

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Chinese Science Bulletin 2013年第10期58卷 1120-1129页

作者： HAO DaCheng gu xiaojie XIAO PeiGen PENG Yong Biotechnology Institute School of EnvironmentDalian Jiaotong University Key Laboratory of Bioactive Substances and Resources Utilization of Chinese Herbal Medicine of Ministry of Education Institute of Medicinal Plant DevelopmentChinese Academy of Medical Sciences

Clematis is a botanical source for various pharmaceutically active components,which has long been used in conventional medicine since the beginning of Chinese *** interest in Clematis medicinal resources has led to additional discoveries of triterpenoid saponins,flavonoids,coumarins,alkaloids and many other compounds in various Clematis species,and to investigations on their chemotaxonomy,molecular phylogeny and *** continuation with our studies on Clematis chemistry and biology,we review the chemistry,chemotaxonomy,molecular biology and phylogeny of Clematis and their relevance to drug efficacy and drug *** databases and technology have been used in literature search in order to characterize the global scientific *** is essential to study more species for both the sustainable utilization of Clematis medicinal resources and finding novel compounds with potential clinical *** biology and omics technologies will play an increasingly important role in future medicinal research involving bioactive compounds of Clematis.

关键词：化学分类学分子生物学药用资源威灵仙生物活性化合物传统医学检索技术分子系统学

Research progress of Chinese herbal medicine compounds and their bioactivities:Fruitful 2020

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Chinese Herbal Medicines 2022年第2期14卷 171-186页

作者： xiaojie gu Dacheng Hao Peigen Xiao Biotechnology Institute School of Environment and Chemical EngineeringDalian Jiaotong UniversityDalian 116028China Institute of Medicinal Plant Development Chinese Academy of Medical SciencesBeijing 100193China

Traditional Chinese medicines(TCMs)have continued to be a treasure *** study of chemodiversity and versatility of bioactivities has always been an important content of *** is amazing progress in the discovery and research of natural components with novel structures and significant bioactivities in *** this paper we review 271 valuable natural products,including terpenoids,steroids,flavonoids,phenylpropanoids,phenolics,nitrogen containing compounds and essential oil,etc.,isolated and identified from TCMs published in journals of Chinese Traditional and Herbal Drugs(Zhong Cao Yao)and Chinese Herbal Medicines(CHMs),and focus on their structures,source organisms,and relevant bioactivities,paying special attention to structural characteristics of novel compounds and newly revealed pharmacological properties of known *** is worth noting that natural products with antitumor activity still constitute the primary object of *** the reported compounds,two new triterpenoids,i.e.,ursolic acid 3-O-β-cis-caffeate and mollugoside E,display remarkable cytotoxicity against PC-9 and HL-60 cell lines,*** known phenolic compounds,i.e.,pyoluteorin,4-hydroxy-3-methoxy cinnamaldehyde and 3,7-dimethoxy-5-hydroxy-1,4-phenanthrenequinone,exhibit significant cytotoxicity against multiple cell *** studies on the free radical scavenging activity of reported compounds are currently *** vitro,three known phenolic compounds,i.e.,3,4-Odicaffeoylquinic acid methyl ester,3,4,5-O-tricaffeoylquinic acid methyl ester and arbutin,had more considerable antioxidant activities than vitamin *** anti-inflammatory,anti-diabetic,hypolipidemic,neuroprotective and antimicrobial activities of isolated compounds are also *** structural characteristics and bioactivities of TCM compounds highlighted here reflect the enormous progress of CHM research in 2020 and will play a positive role in the future drug discovery and de

关键词： chemical constituents medicinal plants natural products pharmacological activities traditional Chinese medicine

Low Temperature Heat Capacity of Zn Substituted Cobalt Ferrite Nanosphere:The Relation between Magnetic Properties and Microstructure

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Journal of Wuhan University of Technology(Materials Science) 2023年第5期38卷 984-995页

作者： YUAN Meng gu xiaojie FU Jie WANG Shaoxu SHI Quan TAN Zhicheng XU Fen College of Environmental and Chemical Engineering Dalian Jiaotong UniversityDalian I16028China Thermochemistry Laboratory Dalian Institute of Chemical PhysicsChinese Academy of ScienceDalian Il6023China guangxi Key Laboratory of Information Materials(guilin University of Electronic Technology) Guilin 541000China

Co_((1-x))ZnxFe_(2)O_(4)nanospheres(x=0,0.5,0.8)with a unidirectional cubic spinel structure were prepared by a solvothermal *** using a range of theoretical and empirical models,the experimental heat capacity values were fitted as a function of temperature over a suitable temperature range to explain the possible relationship between the magnetic properties and microstructure of the *** a result,at a low temperature(T50 K),the Debye temperature decreases with increasing Zn concentration,which is due to the weakening of the interatomic bonding force after the addition of non-magnetic materials to the Co Fe_(2)O_(4)spinel ferrite.

关键词： Co-Zn spinal ferrite nanospheres magnetic properties heat capacity thermodynamic functions PPMS

Bioactivity and constituents of several common seaweeds

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Chinese Science Bulletin 2013年第19期58卷 2282-2289页

作者： ZHANG Yi HAN JinYuan MU Jun FENG Yan gu xiaojie JI YuanXi School of Environmental and Chemical Engineering Dalian Jiaotong University School of Life Science and Biotechnology Dalian University of Technology

Bioactivity and constituents of 8 common seaweeds from Dalian intertidal zone of northern Yellow Sea were investigated. In the anti-methicillin-resistant Staphylococcus aureus (MRSA) test, Symphyocladia latiuscula and Enteromorpha intestinalis showed obvious activities with MICs much lower than 1.0 mg·mL-1 . In the DNA damage repair test (DDRT), Chondrus ocellatu showed selective inhibitory activity against the DNA repair-defective E. coli strain vs. the wild-type E. coli strain; while Sym. latiuscula, Enteromorpha intestinalis and Sar. kjellmanianum showed significant anti-E. coli activity with MICs of 64-128 g·mL-1 . In the anti-Pyricularia oryzae test, Sym. latiuscula and Rh. confervoides strongly inhibited the germination of the spores of P. oryzae on agar plate. In the brine shrimp larvicidal test, Sym. latiuscula, Rh. confervoides and Sar. kjellmanianum exhibited potent toxicity against brine shrimp larvae, with LC50 much lower than 1 mg·mL-1 . The HPTLC analysis revealed their diversified secondary metabolites. The HPLC-DAD-MS analysis of the strongest species Sym. latiuscula and database searching showed that it can produce quite diversified metabolites, including halogenated ones, some of which may be new natural products. The results demonstrated the potentials of these seaweeds in the development of new antibiotics, antitumor drugs, agricultural fungicides and pesticides.

关键词：生物活性成分海藻次生代谢产物金黄色葡萄球菌 DNA损伤修复大肠杆菌 DNA修复黄海北部

Synthesis and Characterization of Polyaniline/MgTiO_(3) Composite with Excellent Thermal and Electrochemical Performance

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Journal of Wuhan University of Technology(Materials Science) 2021年第5期36卷 730-736页

作者： JIN Yazhou XING Weiwei ZHAO Siyu gu xiaojie CHI Liping YUAN Meng XU Fen WANG Shaoxu College of Materials Science and Engineering Dalian Jiaotong UniversityDalian 116028China Dalian Eco-environmental Affairs Service Center Dalian 116028China guangxi Key Laboratory of Information Materials(guilin University of Electronic Technology) Guilin 541004China College of Environmental and Chemical Engineering Dalian Jiaotong UniversityDalian 116028China

This article explores the effects of doping ferroelectric materials MgTiO_(3) with different proportions on the properties of polyaniline(PANI).PANI/MgTiO_(3) composites were prepared by in-situ composite *** transform infrared spectroscopy(FTIR)and X-ray diffraction(XRD)were used to characterize the structure of the *** electron microscope(SEM)was used to characterize the morphology of the *** thermal stability of the composites was investigated by thermogravimetry(TG)and derivative thermogravimetry(DTG).Electrochemical methods(cyclic voltammetry(CV),electrochemical impedance spectroscopy(EIS),and constant current charge-discharge test)were used to compare and analyze the electrochemical performance of the ***-DTG analysis and electrochemical experiments all show that the thermal stability and electrochemical properties of the PANI/MgTiO_(3) composite with a mass ratio of 82/18(w/w)are the *** results indicate that there is a synergistic effect between PANI and MgTiO_(3),which improves the performances of the PANI when the appropriate amount of MgTiO_(3) is added.

关键词： PANI/MgTiO_(3)composites in-situ composite method thermal stability electrochemical performance

改进的LANDMARC定位算法在库位管理中的应用

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计算机应用 2014年第A1期34卷 315-317页

作者：顾李晶顾小杰东南大学自动化学院南京210018

针对库位管理中常用的LANDMARC定位算法在参考标签的选择和信号损耗误差方面存在的问题,提出了改进的LANDMARC定位算法,在不增加参考标签数量的前提下,找到与待定位标签距离最近的参考标签,并通过"距离-损耗"公式,得到精确定位计算的方... 详细信息

针对库位管理中常用的LANDMARC定位算法在参考标签的选择和信号损耗误差方面存在的问题,提出了改进的LANDMARC定位算法,在不增加参考标签数量的前提下,找到与待定位标签距离最近的参考标签,并通过"距离-损耗"公式,得到精确定位计算的方法。结果表明该改进算法提高了定位的精度和收敛速度。

关键词：库存管理定位 LANDMARC

英国资历框架制度改革新进展--基于《16岁后技术教育改革--T级行动计划》的审视

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中国职业技术教育 2020年第9期36卷 52-59页

作者：谷晓洁李延平陕西师范大学陕西西安710062 陕西师范大学教育学院陕西西安710062

资历框架制度的建立,既是一个国家社会、经济和教育发展水平的标志,也是促进个体教育权的实现,发挥教育本体价值和工具价值的有效手段与基本措施。英国是世界上最早建立资历框架的国家之一,从1988年开始基本形成到现在,历经三次大的改... 详细信息

资历框架制度的建立,既是一个国家社会、经济和教育发展水平的标志,也是促进个体教育权的实现,发挥教育本体价值和工具价值的有效手段与基本措施。英国是世界上最早建立资历框架的国家之一,从1988年开始基本形成到现在,历经三次大的改革与创新,已逐渐成长为一个成熟、可实施的框架。2017年10月,英国教育部正式颁布的《16岁后技术教育改革--T级行动计划》,推出了T级别的职业教育资格,通过T级课程、T级考核、T级问责制与T技资助体系,将T级作为一种全新的资格等级引入英国资历框架之中,为学习者提供除普通教育之外的选择路径。

关键词：英国职业教育 T级资格国家资历框架资格证书制度

英国职业资格框架制度改革的价值选择与本质回归

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职业技术教育 2018年第36期39卷 72-79页

作者：谷晓洁李延平陕西师范大学西安710062 陕西师范大学教育学院西安710062

英国职业资格框架制度的建构与发展,经历了几个明显的阶段,每个阶段都有其不同的价值选择:20世纪80年代,英国政府以追求平等的价值观为出发点,构建了职业资格与学术资格等值的制度平台,提高职业教育以及职业资格的地位,确立了基于能力... 详细信息

英国职业资格框架制度的建构与发展,经历了几个明显的阶段,每个阶段都有其不同的价值选择:20世纪80年代,英国政府以追求平等的价值观为出发点,构建了职业资格与学术资格等值的制度平台,提高职业教育以及职业资格的地位,确立了基于能力本位的国家职业资格框架;进入21世纪之后,英国政府引入学分制度,构建出一个更为灵活、更有利于学习者的职业资格框架,强化了以学习者为本的价值理念;在最近十年的改革中,英国政府把追求质量与效力作为其价值选择,强调职业资格框架的规范化、体系化和内部优化,通过促进职业教育与普通教育深度融合和高质量发展,以实现其对人自身和社会发展所具有的整体性、综合性的本质意义回归。

关键词：英国职业资格框架制度普职融通价值选择本质回归