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灌木根系形态对土体强度影响的大型直剪试验研究

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长江科学院院报 2024年第8期41卷 120-127,163页

作者：陈婧逸陈晓清宋东日吕明蒋豪中国科学院、水利部成都山地灾害与环境研究所山地灾害与地表过程重点实验室成都610299 中国科学院大学北京100049

根系形态显著影响根土复合体强度,然而现有研究局限于草本根系根土复合体和室内常规直剪试验。为探究多年生灌木根系形态及空间分布对固土效果的影响,采用大型直剪试验装置(直径400 mm),对原状根土复合体进行了剪切试验。试验中测量了... 详细信息

根系形态显著影响根土复合体强度,然而现有研究局限于草本根系根土复合体和室内常规直剪试验。为探究多年生灌木根系形态及空间分布对固土效果的影响,采用大型直剪试验装置(直径400 mm),对原状根土复合体进行了剪切试验。试验中测量了根系形态参数(根面积比RAR、根长密度、根体积密度和根表面积密度)、根土复合体抗剪强度和剪胀特性,探讨了根系沿深度的分布特征、根土复合体剪胀性以及根系形态参数与根土复合体抗剪强度的相关关系。结果表明,根系加剧了根土复合体的剪胀;在4个根系形态参数中,剪切带上的RAR和根表面积密度与根系对剪切强度的贡献之间相关性较好;Wu模型能反映根系固土的本质,却存在强度被高估或低估的问题。研究成果有助于推动植物根系在固土领域的应用。

关键词：灌木根系形态根土复合体抗剪强度剪胀大型直剪

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数字化转型、客户合作与开放式创新绩效

生产力研究 2024年第7期 112-117页

作者：陈小青陈立梅南京邮电大学管理学院江苏南京210003

数字化时代,客户关系由迎合或主导转向互动与合作,企业创新由封闭走向开放,厘清数字化转型、客户合作和开放式创新绩效三者的关系对于实现中国经济高质量增长具有重要意义。结合新能源企业的数字化转型背景,实证研究结果表明:(1)企业数... 详细信息

数字化时代,客户关系由迎合或主导转向互动与合作,企业创新由封闭走向开放,厘清数字化转型、客户合作和开放式创新绩效三者的关系对于实现中国经济高质量增长具有重要意义。结合新能源企业的数字化转型背景,实证研究结果表明:(1)企业数字化转型对开放式创新绩效具有显著的正向促进作用;(2)客户合作在数字化转型与开放式创新绩效关系中发挥中介效应。数字化转型能够提高客户多样性、关系稳定性和信任,良好的客户关系又有助于企业开放式创新绩效的提高;(3)实施进取型创新战略的企业能够通过客户合作取得更高的开放式创新绩效;而在保守型创新战略下,客户合作不是企业实现高开放式创新绩效的优先考虑要素。

关键词：数字化转型开放式创新客户关系创新战略

Experimental study on the energy dissipation characteristics of debris flow deceleration baffles

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Journal of Mountain Science 2017年第10期14卷 1951-1960页

作者： WANG Fei chen xiao-qing chen Jian-gang Key Laboratory of Mountain Hazards and Earth Surface Processes Institute of Mountain Hazards and EnvironmentChinese Academy of Sciences Chengdu 610041 China CAS Center for Excellence in Tibetan Plateau Earth Sciences Beijing 100101 China State Key Laboratory of Continental Dynamics Department of Geology Northwest University Xi'an 710069 China

Debris flow can cause serious damages to roads, bridges, buildings and other *** several rows of deceleration baffles in the significant influence on the mobility and deposition characteristic of debris flow. The deposit amount first increased then decreased when the flow density rises,flow path can reduce the flow velocity and ensure better protection of life and property. In debris flow prevention projects, deceleration baffles can effectively reduce the erosion of the debris flow and prolong the running time of the drainage *** study investigated the degree to which a 6 m long flume and three rows of deceleration baffles reduce the debris flow velocity and affect the energy dissipation characteristics. The influential variables include channel slope, debris flow density, and spacing between baffle rows. The experimental results demonstrated that the typical flow pattern was a sudden increase in flow depth and vertical proliferation when debris flow flows through the baffles. Strong turbulence between debris flow and baffles can contribute to energy dissipation and decrease the kinematic velocity considerably. The results showed that the reduction ratio of velocity increased with the increase in debris flow density,channel slope and spacing between rows. Tests phenomena also indicated that debris flow density hasand the deposit amount of debris flow density of 1500kg/m^3 reached the maximum when the experimental flume slope is 12°.

关键词： Debris flow Drainage channel Baffles Energy dissipation Flow density

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论毛泽东《反对本本主义》生成的三重逻辑

吕梁学院学报 2024年第3期14卷 13-17页

作者：张云英陈晓庆湖南农业大学马克思主义学院湖南长沙410082

在毛泽东诞辰130周年之际,在全党大兴调查研究之风下,重温《反对本本主义》这篇经典著作,有着十分重要的意义。《反对本本主义》是毛泽东关于调查研究的集大成之作,标志着毛泽东调查研究理论的正式形成。《反对本本主义》的生成并非无... 详细信息

在毛泽东诞辰130周年之际,在全党大兴调查研究之风下,重温《反对本本主义》这篇经典著作,有着十分重要的意义。《反对本本主义》是毛泽东关于调查研究的集大成之作,标志着毛泽东调查研究理论的正式形成。《反对本本主义》的生成并非无源之水、无本之木,有着深厚的历史、理论与实践逻辑。同教条主义等错误思想作斗争,是《反对本本主义》生成的历史逻辑;“没有调查,没有发言权”是反对本本主义的理论武器,成为《反对本本主义》生成的理论逻辑;“到群众中作实际调查去”是反对本本主义的实践武器,成为《反对本本主义》生成的实践逻辑。

关键词：《反对本本主义》历史逻辑理论逻辑实践逻辑

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Characteristics of viscous debris flow in a drainage channel with an energy dissipation structure

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Journal of Mountain Science 2016年第2期13卷 223-233页

作者： chen Jian-gang chen xiao-qing chen Hua-yong ZHAO Wan-yu CAS Key Laboratory of Mountain Hazards and Earth Surface Processes Institute of Mountain Hazards and Environment Chinese Academy of Sciences Chengdu 610041 China CAS Center for Excellence in Tibetan Plateau Earth Sciences

A new type of drainage channel with an energy dissipation structure has been proposed based on previous engineering experiences and practical requirements for hazard mitigation in earthquakeaffected *** studies were performed to determine the characteristics of viscous debris flow in a drainage channel of this type with a slope of 15%.The velocity and depth of the viscous debris flow were measured,processed,and subsequently used to characterize the viscous debris flow in the drainage *** of this experiment showed that the surface of the viscous debris flow in a smooth drainage channel was smoother than that of a similar debris flow passing through the energy dissipation section in a channel of the new type studied ***,the flow patterns in the two types of channels were similar at other *** experimental results show that the depth of the viscous debris flow downstream of the energy dissipation structure increased gradually with the length of the energy dissipation *** addition,in the smooth channel,the viscous debris-flow velocity downstream of the energy dissipation structure decreased gradually with the length of the energy dissipation ***,theviscous debris-flow depth and velocity were slightly affected by variations in the width of the energy dissipation structure when the channel slope was 15%.Finally,the energy dissipation ratio increased gradually as the length and width of the energy dissipation structure increased;the maximum energy dissipation ratio observed was 62.9%(where B = 0.6m and L/w = 6.0).

关键词： Debris flow Drainage channel Energy dissipation structure Geological disaster

Characteristics of root-permeated soil under simple-shear and direct-shear conditions

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Journal of Mountain Science 2023年第8期20卷 2422-2435页

作者： chen Jing-yi chen xiao-qing SONG Dong-ri LV Ming GUO Han-qing SADEGHI Hamed Laboratory of Mountain Hazards and Earth Surface Process/Institute of Mountain Hazards and Environment Chinese Academy of SciencesChengdu 610299China University of Chinese Academy of Sciences Beijing 100049China Department of Civil Engineering Sharif University of TechnologyTehran ***Iran

The simple-shear condition is closer to reality than the direct-shear condition for simulating the mechanical behavior of vegetated soil slope under shallow ***,study on simple-shear characteristics for vegetated slope is still insufficient,and there lacks intuitive comparison of characteristics between these two shear *** this study,large-scale simple-shear and direct-shear experiments were conducted on soil permeated by roots of Amorpha fruticosa to investigate the shear strength and *** stress-displacement relationship of each sample was obtained and further normalized to unify the influence of root *** results reveal that the direct-shear condition overestimates the shear strength of root-permeated soils(by 41%)and thus the estimation of slope stability based on the parameters of direct-shear condition is not ***,the initial stiffness of root-permeated soil under simple-shear condition is 34%lower than that under direct-shear *** higher strength and stiffness under direct-shear condition are caused by the following reasons:the shear plane does not have the lowest strength,the shear area is decreasing,and the shear zone is *** significant deformation(lower stiffness)revealed by the simple-shear condition facilitates the application of early warning for vegetated shallow landslides.

关键词： Simple-shear condition Direct-shear condition Root-permeated soil Shear strength Shear stiffness Shallow landslide

Multi-model assessment of glacio-hydrological changes in central Karakoram, Pakistan

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Journal of Mountain Science 2021年第8期18卷 1995-2011页

作者： Javed HASSAN chen xiao-qing Rijan Bhakta KAYASTHA NIE Yong Key Laboratory of Mountain Hazards and Earth Surface Process Institute of Mountain Hazards and EnvironmentChinese Academy of SciencesChengdu610041China China-Pakistan Joint Research Center on Earth Sciences CAS-HECIslamabad45320Pakistan University of Chinese Academy of Sciences Beijing100049China Himalayan Cryosphere Climate and Disaster Research Center(HiCCDRC)Department of Environmental Science and EngineeringSchool of ScienceKathmandu UniversityKavrepalanchowk45200Nepal

The multi-model assessment of glacio-hydrological regimes can enhance our understanding of glacier response to climate *** improved knowledge can uplift our computing abilities to estimate the contributing components of the river *** study examined and compared the hydrological responses in the glacier-dominated Shigar River basin(SRB)under various climatic scenarios using a semi-distributed Modified Positive Degree Day Model(MPDDM)and a distributed Glacio-hydrological Degree-day Model(GDM).Both glacio-hydrological models were calibrated and validated against the observed hydro-meteorological data from 1988–1992 and 1993–*** and precipitation data from Shigar and Skardu meteorological stations were used along with field estimated degree-day factor,temperature,and precipitation *** results from both models indicate that the snow and ice melt are vital contributors to sustain river flow in the ***,MPDDM estimated 68%of rain and baseflow contribution to annual river runoff despite low precipitation during the summer monsoon,while GDM estimated 14%rain and baseflow ***,MPDDM calculated 32%,and GDM generated 86%of the annual river runoff from snow and ice *** simulated river discharge with 0.86 and 0.78 NSE for calibration and validation,***,GDM simulated river discharge with improved accuracy of 0.87 for calibration and 0.84 NSE for the validation *** snow and ice melt is significant in sustaining river flow in the SRB,and substantial changes in melt characteristics of snow and ice are expected to have severe consequences on seasonal water *** on the sensitivity analysis,both models’outputs are highly sensitive to the variation in ***,compared to MPDDM,GDM simulated considerable variation in the river discharge in climate scenarios,RCP4.5 and 8.5,mainly due to the higher sensitivity of GDM model outputs to temperature *** i

关键词： Modified Positive Degree Day Model(MPDDM) Glacio-hydrological Degree-day Model(GDM) Glacio-hydrological Modelling Climatic Variation Snow and ice contributions

Neuropsychiatric disorders and cognitive dysfunction in patients with Cushing＇s disease

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Chinese Medical Journal 2013年第16期126卷 3156-3160页

作者： chen Yu-fan LI Yun-feng chen xiao SUN qing-fang Department of Neurosurgery Ruijin Hospital Affiliated Hospital ofShanghai Jiaotong University Shanghai 200025 China

Objective To review the main neuropsychiatric disorders and cognitive deficits in patients with Cushing＇s disease （CD） and the associated pathophysiological mechanisms underlying *** mechanistic details may provide recommendations for preventing or treating the cognitive impairments and mood disorders in patients with *** sources Data were obtained from papers on psychiatric and cognitive complications in CD published in English within the last 20 *** perform the PubMed literature search,the following keywords were input：cushing＇s disease,cognitive,hippocampal,or *** selection Studies were selected if they contained data relevant to the topic addressed in the particular *** of the limited length of this article,we have frequently referenced recent reviews that contain a comprehensive amalgamation of literature rather than the actual source *** Patients with active CD not only suffer from many characteristic clinical features,but also show some neuropsychiatric disorders and cognitive *** the psychiatric manifestations,the common ones are emotional instability,depressive disorder,anxious symptoms,impulsivity,and cognitive *** effects of previous glucocorticoid （GC） excess on the central nervous system,such as hippocampal and the basal ganglia,is the most reasonable *** secretion of cortisol brings much structural and functional changes in hippocampal,such as changes in neurogenesis and morphology,signaling pathway,gene expression,and glutamate *** volume loss can be found in most patients with CD,and decreased glucose utilization caused by GCs may lead to brain atrophy,neurogenesis impairment,inhibition of long-term potentiation,and decreased neurotrophic factors; these may also explain the mechanisms of GC-induced brain atrophy and hippocampal *** Brain atrophy and hippocampal changes caused by excess secretion of cortisol are thoug

关键词： cushing's disease psychology cognitive symptoms hippocampal glucocorticoids

Characteristics of a Drainage Channel with Staggered Indented Sills for Controlling Debris Flows

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Journal of Mountain Science 2014年第5期11卷 1242-1252页

作者： chen xiao-qing YOU Yong chen Jian-gang HUANG Kai LI De-ji Key Laboratory of Mountain Hazards and Earth Surface Processes Chinese Academy of Sciences Institute of Mountain Hazards and Environment Chinese Academy of Sciences and Ministry of Water Conservancy

The characteristics of a new type of drainage channel with staggered indented sills for controlling debris flows were studied. The intermediate fluid in the non-viscous debris flow exhibited a helical movement, whereas the fluid near the sidewall had a stop-start movement pattern; the viscous debris flow exhibited a stable structure between the indented sills. The experimental results indicate that the mean velocity of the debris flow increased with increasing channel gradients, and the debris flow velocity was slightly affected by the angle of the sills. The average velocity of the non-viscous debris flow increased in the range of(0.5–1.5) interval between the indented sills, whereas the average velocity of the viscous debris flow increased initially and then decreased in the range of(0.75–1.25) interval between the indented sills. The depth of the non-viscous debris flow tended to gradually increase as the channel gradients increased, whereas the depth of the viscous debris flow gradually decreased as the channel gradients increased. When the discharge of the debris flow was constant, the angle and the interval between the indented sills had a slight effect on the depth of the viscous debris flow, whereas the depth of the non-viscous debris flow exhibited a different trend, as the sill angles and intervals were varied.

关键词： Debris flow Drainage channel Staggered indented sill Wenchuan earthquake