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Effect of grassland degradation on soil quality and soil biotic community in a semi-arid temperate steppe

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Ecological Processes 2020年第1期9卷 749-759页

作者： Xu Han Yuhui Li Xiaofang Du Yingbin Li Zhengwen Wang siwei jiang Qi Li Erguna Forest-Steppe Ecotone Research Station Institute of Applied EcologyChinese Academy of SciencesShenyang 110016China University of Chinese Academy of Sciences Beijing 100049China

Grasslands provide a number of ecosystem services for human *** of grasslands results in the loss of biodiversity and leads to the deterioration of ecosystem *** order to accurately assess the influence of grassland degradation on belowground ecosystems,we conducted experiments on a temperate steppe with different levels of degradation and investigated the influence of degradation on soil quality and soil biotic *** results showed that grassland degradation significantly decreased soil quality,with lower values of soil quality index(SQI)observed in the degraded grassland than the meadow steppe and the grassland from the forest-steppe *** in the SQI along the grassland degradation gradient were positively correlated with soil carbon stock and the aboveground biomass,and negatively correlated with the root shoot *** trophic diversity and the ratio of fungal to bacterial PLFA were lower in the degraded grassland than the grassland from the forest-steppe *** dissimilarities in soil microbial and nematode community composition increased with the changes in soil quality *** results indicate that soil quality index based on the minimum data sets could effectively assess the influence of grassland degradation on soil biodiversity and ecosystem *** order to effectively restore degraded grasslands,the key contributors to the soil quality,such as soil carbon,should be taken on priority basis for revitalizing the soil biodiversity and ecosystem function.

关键词： Soil quality Soil biodiversity Grassland degradation Soil nematode community

Conservation of weathered historic sandstone with biomimetic apatite

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Chinese Science Bulletin 2012年第17期57卷 2171-2176页

作者： YANG FuWei LIU Yan ZHU YuanCheng LONG ShiJia ZUO GuoFang WANG ChangQing GUO Feng ZHANG BingJian jiang siwei Key Laboratory for New Molecule Material Design and Function Tianshui Normal University Tianshui 741000 China Department of Chemistry Zhejiang University Hangzhou 310027 China The Art Museum of Dazu Rock Carvings Chongqing 632360 China

The conservation of weathered historic sandstone with apatite was *** on the growth mechanism of bone,calcium and phosphorus were introduced into weathered sandstone and then mineralized at room *** conservation efficiency was investigated by scanning electron microscopy(SEM),energy-dispersive X-ray spectroscopy(EDX),transmission electron microscopy(TEM),selected area electron diffraction(SAED),X-ray diffraction(XRD),and compressive strength,capillary water uptake,water vapor permeability and weather resistance *** SEM,EDX,TEM,SAED and XRD results showed that the produced hydroxyapatite could reunite the weathered stone blocks and provide sufficient reinforcement to hold them *** results of the various tests indicated that the compressive strength and weather resistance of the treated samples was improved *** addition,because of the porous nature of apatite,the water vapor permeability of the treated stone was not affected and its breathability was maintained.

关键词：羟基磷灰石风化砂岩历史意义扫描电子显微镜透射电子显微镜仿生保育 X射线光谱仪

Influence of particle size distribution on biocarbonation method produced microbial restoration mortar for conservation of sandstone cultural relics

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Biogeotechnics

Biogeotechnics 2023年第4期1卷 2-12页

作者： Yang Yang Shaokang Han Hanlong Liu Huili Chen siwei jiang School of Civil Engineering Chongqing UniversityChongqing 400045China Dazu Rock Carvings Chongqing 402360China

Biocarbonation of reactive magnesia based on microbially induced carbonate precipitation(MICP)process is a sustainable geotechnical reinforcement technology for strength development and permeability *** method can be used to produce microbial restoration mortar(MRM)for the application of stone cultural relics *** this paper,the influence of particle size distribution on the strength and porosity of MRM was *** mixing fine and coarse sandstone powder in various proportions,nine different particle size distributions were obtained to investigate the restoration performance,including the unconfined compressive strength(UCS),porosity,and color *** results indicate that the well-graded particle size distribution can lead to the UCS improvement and porosity reduction of *** findings also imply that adding fine sandstone powder to the coarse sandstone powder can provide extra bridging contacts within the soil *** bridging contacts can be easily connected by the precipitated hydrated magnesium carbonates(HMCs)minerals,consequently resulting in more effective bonding and filling within the pore *** microstructural images of MRM confirm the formation of HMCs,which exhibited a dense network structure,filling out the gap and bonding the sandstone ***,the microbial restoration mortar showed a high weather resistance to dry-wet cycles,acid rain,and salt attack,which is attributed to better stability and strength of HMCs than the original calcic cemented minerals in sandstone.

关键词： Biocarbonation Cultural relics Microbially induced carbonate precipitation (MICP) Particle size distribution Restoration Sandstone

注塑温度及衰减时间对改性聚丙烯注塑件气味、VOC的影响

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现代机械 2018年第6期 88-90页

作者：姜思维重庆化工职业学院重庆401228

通过研究改性聚丙烯(PP)注塑件在不同注塑温度和衰减时间下气味、VOC的变化规律,寻找降低PP注塑件气味、改善VOC水平的方案。

关键词：改性聚丙烯注塑温度衰减时间气味 VOC

多元统筹视角下产业园区更新的治理转型——以上海高桥某产业园区为例

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上海城市管理 2024年第6期33卷 80-88页

作者：姜思伟上海城策行建筑规划设计咨询有限公司规划一所

城市高质量发展要求产业园区对存量低效产业用地进行更新与转型,但由于存在主体缺乏动力、整体难以引导、市场意愿不足、过程协商复杂、技术缺乏统筹等问题,很大程度上制约了园区转型的有序推进与高效实施。基于多元统筹的视角,提出“... 详细信息

城市高质量发展要求产业园区对存量低效产业用地进行更新与转型,但由于存在主体缺乏动力、整体难以引导、市场意愿不足、过程协商复杂、技术缺乏统筹等问题,很大程度上制约了园区转型的有序推进与高效实施。基于多元统筹的视角,提出“主体、地块、环节”三位一体的产业园区更新转型的治理框架。以上海市高桥某产业片区转型为例,围绕产业发展目标与空间优化导向,探索主体、地块、环节三个维度的治理统筹,提出平台赋能与政策引导、一地一策与空间弹性设计、过程联动与全生命周期管理等治理策略。研究认为:产业园区更新应从传统产业规划模式向多元统筹的新模式转变,有助于优化园区内各主体之间的统筹协作,更好地促进规划策划与实施运营的衔接,提升更新转型项目的财务可持续水平,保障园区转型全面高效落地。

关键词：多元统筹产业园区园区转型城市更新治理创新

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空管自动化系统应用ADS-B数据的优化探索与风险分析

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科技创新导报 2021年第17期18卷 75-77页

作者：蒋斯炜民航华北空管局北京100621

随着ADS-B新技术的不断发展,探索ADS-B在自动化系统的应用是对空监视技术未来的发展方向。本文主要通过简介ADS-B技术在空管运行领域的优势,探索ADS-B功能的发展方向。通过在自动化系统截取A DS-B数据报文,分析数据项内容,并以自动化系... 详细信息

随着ADS-B新技术的不断发展,探索ADS-B在自动化系统的应用是对空监视技术未来的发展方向。本文主要通过简介ADS-B技术在空管运行领域的优势,探索ADS-B功能的发展方向。通过在自动化系统截取A DS-B数据报文,分析数据项内容,并以自动化系统监视数据处理模块为例,探索ADS-B位置、高度等信息对自动化系统的优化,并提出具体的监视数据处理模块中多传感器跟踪结构的业务流程。同时,分析ADS-B信息未来在民航空管运行中存在的风险,并提出建立ADS-B数据评估机制以及黑名单运行机制的建议。

关键词： ADS-B 自动化系统数据解析卡尔曼滤波数据融合

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温度影响下石窟砂岩力学特性试验研究

岩石力学与工程学报 2024年第S01期43卷 3310-3320页

作者：朱鹏熹王成龙蒋思维仉文岗陈卉丽重庆大学土木工程学院重庆400045 大足石刻研究院重庆402360 重庆市地质矿产勘查开发局重庆401121

石窟寺所处环境长期面临着冷热交替作用,温度变化往往导致石窟围岩的力学性质发生变化。以重庆大足石刻石窟砂岩为研究对象,通过单轴压缩试验和巴西劈裂试验,对石窟砂岩的力学特性展开试验研究,分析不同温度和冷热循环条件下的石窟砂岩... 详细信息

石窟寺所处环境长期面临着冷热交替作用,温度变化往往导致石窟围岩的力学性质发生变化。以重庆大足石刻石窟砂岩为研究对象,通过单轴压缩试验和巴西劈裂试验,对石窟砂岩的力学特性展开试验研究,分析不同温度和冷热循环条件下的石窟砂岩的应力-应变曲线、岩石强度、峰值应力和应变、弹性模量和破坏形态。结果表明:(1)10次冷热循环后,砂岩的单轴抗压强度降低,其中相较于自然冷却,水冷却循环会显著减小砂岩的单轴抗压强度。砂岩的抗拉强度受冷却方式影响较大,低温水冷却循环下砂岩的抗拉强度最小。(2)10次冷热循环作用后,砂岩的峰值应变降低。相较于自然冷却,水冷却循环会减小石窟砂岩的弹性模量,当冷热循环次数由5次增加到10次时,砂岩的弹性模量也会减小。(3)砂岩在单轴压缩下的破坏模式以剪切破坏为主,而冷热循环作用后砂岩破坏模式变复杂。砂岩在巴西劈裂下的破坏形式的主要区别在于裂纹形态和数量,遇水冷却循环作用后,砂岩主裂纹由直线形向弧形转化,或产生次裂纹。

关键词：岩石力学石窟砂岩温度影响单轴压缩巴西劈裂力学特性

Distribution of Soil Organic Carbon and Total Nitrogen of the Cultivated Layer under Different Tillage Practices

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Distribution of Soil Organic Carbon and Total Nitrogen of th...

2011 International Conference on New Technology of Agricultural Engineering(ICAE 2011)

作者： Xuekun Hou Heilongjiang Bayi Agricultural University Daqing,China Yaolei Wang,siwei jiang Institute of Applied Ecology,Chinese Academy of Sciences Shenyang,China

To evaluate the carbon and nitrogen sequestration capacity of different tillage practices,soil organic carbon and nitrogen concentrations and storages of the cultivated layer under different tillage practices(conventional tillage,no-tillage and fallow)were *** results showed that soil organic carbon under different tillage practices were significantly different among different soil depths and 0-5 cm >5-15 cm>15-30 cm(except for the conventional tillage in booting stage).The concentration of soil organic carbon in no-tillage was higher than that in conventional tillage and *** concentrations of soil total nitrogen were significantly different among different treatments in 5-15 cm of jointing stage and 0-5 cm of booting and ripening stage,and no-tillage >conventional tillage>*** organic carbon storage in the cultivated layer(0-30 cm)was increased by no-tillage practice,but soil nitrogen storage was not affected significantly by tillage *** organic carbon and total nitrogen were negatively correlated with pH,exchangeable K + and Ca 2+.

关键词： no-tillage organic carbon total nitrogen storage

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试析“以人为本”的企业文化

成都航空职业技术学院学报 2011年第2期27卷 79-81页

作者：蒋思维成都航空职业技术学院四川成都610021

任何一门学科都有其特定的研究对象,企业文化也不例外,企业文化由企业内因素和企业外因素共同构成,二者相互作用促进企业文化的发展,而企业内因素之一就是员工,因此,企业文化的研究主体之一是企业员工,研究内容是"以人为本",这使得管理... 详细信息

任何一门学科都有其特定的研究对象,企业文化也不例外,企业文化由企业内因素和企业外因素共同构成,二者相互作用促进企业文化的发展,而企业内因素之一就是员工,因此,企业文化的研究主体之一是企业员工,研究内容是"以人为本",这使得管理人员能够更透彻地了解企业中的文化现象,追求企业价值,从而使员工受益。

关键词：以人为本企业文化员工