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广东省植被生态质量演变与气象条件贡献分析

生态环境学报 2024年第5期33卷 679-688页

作者：何沐全石艳军王晨茜罗祖红张少通广州气象卫星地面站广东广州510640

植被生态质量体现了植被的生产功能、多样性和服务功能,其变化受气象条件和人类活动的共同影响,科学地评估植被变化的气象条件贡献率对区域生态修复和应对气候变化具有重要的意义。以广东省为例,基于中国气象局发布的NDVI、FVC、NPP和... 详细信息

植被生态质量体现了植被的生产功能、多样性和服务功能,其变化受气象条件和人类活动的共同影响,科学地评估植被变化的气象条件贡献率对区域生态修复和应对气候变化具有重要的意义。以广东省为例,基于中国气象局发布的NDVI、FVC、NPP和气象条件贡献率等数据,运用统计分析与空间分析方法,探讨了广东省植被生态质量的时空分布特征,并定量评估了气象条件对广东植被变化的贡献。结果表明:1)2001-2022年,广东省的NDVI、FVC和NPP均呈波动上升变化,三者的年平均变化范围分别为0.494-0.627、0.594-0.706和C 831-1.15×103 g∙m^(-2),多年平均值分别为0.565、0.653和C 976 g∙m^(-2),峰值分别出现于2016年(NPP)、2021年(NDVI)、2022年(FVC),谷值出现于2005年(NDVI、FVC)和2003年(NPP);2)空间上,广东省植被生态质量存在明显的区域差异,表现为粤北>粤东北>粤西>粤东>珠三角,其中阳江、肇庆、云浮、清远、韶关等城市植被生态质量较好,东莞、佛山较差;3)近20多年来气象条件对广东省植被生态质量变化的影响以正贡献为主,气象条件贡献率整体以-1.60×10^(-2)/a的变化率呈波动下降趋势,气象条件对广东植被变化的影响总体变小;4)气象条件对粤北植被的影响以正向驱动为主,对粤东、粤西以负向驱动为主且对粤东的影响程度大于粤西,其中2007、2017-2018、2020-2022年气象条件对广东植被生态质量变化影响以负贡献为主,2022年呈高度负贡献。气象因素对广东植被生态质量变化的影响较大且存在明显的区域差异,在气象条件相对稳定的情况下,植被长势明显变好。

关键词：植被植被生态质量气象条件贡献率 MODIS 时空分布广东省

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古土壤层间富水对黄土场地湿陷性的影响

西北大学学报（自然科学版） 2024年第1期54卷 72-83页

作者：李琳王家鼎谷琪张登飞焦少通西北大学地质学系/大陆动力学国家重点实验室陕西西安710069

黄土地层中往往交替分布着多层红色古土壤层,由于其硬度相对较高,遇水不易湿陷,对黄土地层湿陷量的测量结果有很大的影响。然而,对于古土壤对湿陷量的控制作用目前还缺乏相关研究,导致对湿陷地层湿陷量的科学取舍缺乏理论依据。为此该... 详细信息

黄土地层中往往交替分布着多层红色古土壤层,由于其硬度相对较高,遇水不易湿陷,对黄土地层湿陷量的测量结果有很大的影响。然而,对于古土壤对湿陷量的控制作用目前还缺乏相关研究,导致对湿陷地层湿陷量的科学取舍缺乏理论依据。为此该文统计了黄土高原区的浸水试验结果,分析了不同区域湿陷量室内外差异特征,并以西安地区两个试验场地的大型浸水试验为研究对象,进行了不同试验条件下土体中水分的扩散、含水率的变化、土压力变化以及累计湿陷量等测量工作。最终结果表明,古土壤层的存在阻碍湿陷进程,在阻止水分下渗的同时,阻碍深部地层湿陷量传递至地表,使得湿陷量实测值与计算值之间的差异与古土壤层数呈现正相关的趋势。该文将为普遍存在古土壤的黄土地层自重湿陷机理的研究提供参考。

关键词：古土壤浸水试验湿陷性湿陷系数黄土

Wave flume experiments on dynamics of the bottom boundary layer in silty seabed

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Acta Oceanologica Sinica 2020年第5期39卷 96-104页

作者： Mingzheng Wen Yonggang Jia Zhenhao wang shaotong Zhang Hongxian Shan Shandong Provincial Key Laboratory of Marine Environment and Geological Engineering Ocean University of ChinaQingdao 266100China Tianjin Center China Geological SurveyTianjin 300170China Laboratory for Marine Geology Pilot National Laboratory for Marine Science and Technology(Qingdao)Qingdao 266061China First Institute of Oceanography Ministry of Natural ResourcesQingdao 266061China

The objectives of this study are carried out a series of controlled large wave flume experiments using fine-grained sediment from the Huanghe River Delta,exploring the complete sequence of sediment behavior in the bottom boundary layer(BBL)during wave-induced *** results show that:(1)The BBL in silty seabed is exposed to a progressive wave,goes through a number of different stages including compaction before liquefaction,sediment liquefaction,and compaction after liquefaction,which determines the range and thickness of BBL.(2)With the introduction of waves,first,the sediment surface has settled by an amount S(S=1–2 cm)in the course of wave loadings with an insufficient accumulation of pore water *** a thin high concentration layer formed the near-bed bottom.(3)Once the liquefaction sets in,the liquefied sediment with an‘orbital motion’and the sub-liquefied sediment form a two-layer-sediment *** range of BBL extends downwards and stopped at a certain depth,subsequently,develops upwards with the compaction ***,resuspended sediments diffuse to the upper water column.(4)During the dynamics process of the BBL beneath progressive waves,the re-suspended sediment increment ranked as sediment liquefaction>erosion before liquefaction>compaction after liquefaction.

关键词： bottom boundary layer suspended sediment concentration liquefaction compaction Yellow River Delta

双ROI透视触发扫描在提高CCTA图像质量中的可行性研究

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中国医疗设备 2022年第6期37卷 89-92,101页

作者：何拓姚悦王少彤向颖丁墩李晓会西安交通大学第二附属医院医学影像科陕西西安710004

目的探讨双感兴趣区(Region of Interest,ROI)透视触发扫描方法在提高冠状动脉CT血管成像(Coronary Computed Tomography Angiography,CCTA)图像质量方面的应用价值。方法前瞻性收集2019年12月至2020年5月在我院行CCTA的100例患者的资... 详细信息

目的探讨双感兴趣区(Region of Interest,ROI)透视触发扫描方法在提高冠状动脉CT血管成像(Coronary Computed Tomography Angiography,CCTA)图像质量方面的应用价值。方法前瞻性收集2019年12月至2020年5月在我院行CCTA的100例患者的资料。使用随机数字表法将患者分成实验组和对照组,实验组采用肺动脉及主动脉双ROI透视触发法进行扫描,对照组采用智能追踪触发法进行扫描。图像评价使用Likert 5分制量表法对2组图像进行主观评分;测量并比较2组图像主动脉根部、左冠状动脉主干及右冠状动脉主干的CT值、噪声值、信噪比(Signal to Noise Ratio,SNR)及对比噪声比(Contrast to Noise Ratio,CNR)等客观评价参数。结果实验组的主观评分,以及主动脉根部与左冠状动脉的CT值、SNR及CNR均优于对照组,差异具有统计学意义(P0.05)。结论双ROI透视触发扫描方法可客观可视化实现CCTA扫描并可有效提高冠状动脉成像的图像质量。

关键词：计算机断层扫描冠状动脉CT血管成像智能追踪触发法透视触发图像质量

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干湿循环作用下黄土厚度对其裂隙发育的影响

西北大学学报（自然科学版） 2024年第1期54卷 1-10页

作者：焦少通王家鼎张登飞戚利荣李帅李琳李珊西北大学地质学系/大陆动力学国家重点实验室陕西西安710069

黄土体长期处于降雨和蒸发的湿热耦合环境,极易诱发土体裂隙产生,显著弱化土体的结构性和完整性,从而影响工程区域的建设。因此,对干湿循环作用下不同厚度的黄土开裂特性研究十分必要。该文通过室内干湿循环试验,记录试样的含水率变化... 详细信息

黄土体长期处于降雨和蒸发的湿热耦合环境,极易诱发土体裂隙产生,显著弱化土体的结构性和完整性,从而影响工程区域的建设。因此,对干湿循环作用下不同厚度的黄土开裂特性研究十分必要。该文通过室内干湿循环试验,记录试样的含水率变化和裂隙发育情况,利用数字图像处理技术,结合分形维数对裂隙网络进行分析。试验结果表明,蒸发路径和含水量的不同导致土体水分蒸发速度不同,土体越厚,水分蒸发速度越慢。界面摩擦力影响土体开裂过程,土体越厚,裂隙发育越慢,裂纹网络复杂性越低。随着干化的进行,界面摩擦力逐渐降低,土体收缩明显,干湿循环效应导致土体颗粒重新组合,加快水分蒸发过程,土体表面会不断劣化。研究结果可为地质灾害防治提供指导。

关键词：干湿循环土体厚度裂隙特征分形维数摩擦力

Adsorption Kinetics of Methylene Blue from Aqueous Solutions onto Palygorskite

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Acta Geologica Sinica(English Edition) 2006年第2期80卷 236-242页

作者： PENG Shuchuan wang Shisheng CHEN Tlanhu JIANG shaotong HUANG Chuanhui School of Resources and Environmental Engineering Hefei University of Technology Heifei Anhui 230009 Department of Soil Chemistry and Environmental Protection Institute of Soil Science Chinese Academy of Sciences Nanjing Jiangsu 210008 Department of Chemistry University of Sciences and Technology of China Heifei Anhui 230009

The adsorption kinetics of methylene blue from aqueous solutions on purified palygorskite was investigated. The kinetics data related to the adsorption of methylene blue from aqueous solutions are in good agreement with the pseudo-second order equation in ranges of initial concentration of 120-210 mg/L, oscillation speed of 100-200 r/min and temperature of 298-328K. The experimental results show that methylene blue is only adsorbed onto the external surface of purified palygorskite, and the apparent adsorption activation energy is 13.92 kJ/mol. The relatively low apparent adsorption activation energy suggests that the adsorption of methylene blue involves in not only a chemical, but also a physical adsorption process, and it is controlled by the combination of chemical adsorption and fiquid-film diffusion.

关键词： purified palygorskite adsorption methylene blue kinetics

Experimental Researches on the Accuracy of Micro- Electromechanical Accelerometer-Array in Seafloor Failure Deformation Measurement

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Journal of Ocean University of China 2022年第5期21卷 1198-1204页

作者： wang Zhenhao LIU Xiaolei ZHANG shaotong WEN Mingzheng SHAN Hongxian JIA Yonggang First Institute of Oceanography Ministry of Natural ResourcesQingdao 266061China Shandong Provincial Key Laboratory of Marine Environment and Geological Engineering Ocean University of ChinaQingdao 266100China Laboratory for Marine Geology Qingdao National Laboratory for Marine Science and TechnologyQingdao 266061China Tianjin Center China Geological SurveyTianjin 300170China

At present,there are few technologies applied to in situ observation of seabed deformation,among which the micro-electromechanical accelerometer-array(hereinafter referred to as accelerometers array)is a very advantageous measurement method,with both commercial products and successful application ***,the coupling effect between accelerometer-array and sur-rounding soil and the linkage effect of accelerometer-array itself during the deformation may influence the accuracy and reliability of the measurement data.A simulation test chamber was designed and processed,and four groups of simulation tests were carried out to explore the coupling effect and linkage effect of accelerometer-array in the soil with different degree of *** results show that the accelerometer-array and the soil coupled well,and the coupling effect is positively correlated with the degree of soil *** ratio of accumulative deviation to soil lateral deformation is high at the initial stage of deformation(0-50 mm)and reduced with the continuous increase of deformation(>100 mm).In the process of liquefied soil deformation,the linkage effect of accelerometer array can be ignored,and is negatively correlated with the degree of soil consolidation.A concept to improve the measurement accu-racy of accelerometer-array in different seafloor failure deformation modes is *** research results provide references for the modification of accelerometer-array and the improvement for other flexible rod-shaped deformation sensors.

关键词： micro-electromechanical accelerometer-array seafloor failure deformation in situ observation coupling effect linkage effect

海水环境中Ti6321焊接接头点蚀萌生与生长模型

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中国有色金属学报 2024年第8期34卷 2661-2672页

作者：王炎培范林邵刚勤白雪寒刘少通张海兵孙明先武汉理工大学材料复合新技术国家重点实验室武汉430070 中国船舶集团有限公司第七二五研究所海洋腐蚀与防护全国重点实验室青岛266237

针对钛合金焊接接头在海水中长期服役可能面临的点蚀风险,通过电化学测试、预制点蚀凹坑试样的弯曲加载浸泡试验,结合累积概率、分布函数等统计学分析方法研究了Ti6321焊接接头在海水环境中的点蚀萌生和生长行为,利用极值统计法建立了... 详细信息

针对钛合金焊接接头在海水中长期服役可能面临的点蚀风险,通过电化学测试、预制点蚀凹坑试样的弯曲加载浸泡试验,结合累积概率、分布函数等统计学分析方法研究了Ti6321焊接接头在海水环境中的点蚀萌生和生长行为,利用极值统计法建立了点蚀生长动力学模型。结果表明:点蚀萌生时间包括点蚀萌生的驱动电位达到阈值的时间和亚稳态点蚀产生并向稳态点蚀转变的诱导时间,根据点蚀萌生时间的试验和理论推算结果保守估计,在静态海水自然腐蚀条件下,Ti6321焊接接头难以自发产生稳态点蚀;90%R_(e)弯曲加载条件下Ti6321焊接接头在海水中的最大点蚀深度符合Gumbel分布。本研究为钛合金在海水环境中点蚀萌生和生长提供了一种基于电化学、统计分析的快速试验和预测方法。

关键词：钛合金焊接接头点蚀电化学统计分析

Study on the adsorption kinetics of orthophosphate anions on layer double hydroxide

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Chinese Journal Of Geochemistry 2009年第2期28卷 184-187页

作者： PENG Shuchuan LULu wang Jin HAN Lu CHEN Tianhu JIANG shaotong School of Resources and Environment Hefei University of Technology Hefei 230009 China

A kinetic study was conducted on the adsorption of orthophosphate anions on layer double hydroxide (LDH). The adsorption has proved itself to be a spontaneous endothermic process and is large in capacity and rate. The adsorption isotherm correlates well with the Freundlich model, and a rise in temperature will lead to an increase in adsorption efficiency. Additionally, the results suggested that the adsorption is an entropy-increasing process and is in good agreement with the pseudo-second order kinetics. The free energy (ΔG) of adsorption of orthophosphate onto LDH varies within the range of -1.75--3.34 kJ/mol, the enthalpy (ΔH) varies by 7.96 kJ/mol and the entropy (ΔS) by 33.59 kJ/mol. The adsorption activation energy is 8.3 kJ/mol, showing that the adsorption of orthophosphate onto LDH is determined to be a physical adsorption.

关键词：吸附动力学金属氢氧化物正磷酸盐 Freundlich模型子层吸附等温线吸热过程吸附效率