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Significant lake expansion has accelerated permafrost degradation on the Qinghai-Tibet Plateau

Journal of Mountain Science 2024年第1期21卷 68-83页

作者： LI Qingpeng LIU Wenhui LIU Hairui zhou guanghao SONG Xianteng LI Qing LUO Bingnan SONG Bangxu ZHANG Qi Department of Geological Engineering Qinghai UniversityXining 810016China College of Eco-Environmental Engineering Qinghai UniversityXining 810016China Xining Center for Integrated Natural Resources Survey China Geological SurveyXining 810000China

In recent years, lakes on the Qinghai-Tibet Plateau have become more responsive to climate change. In September 2011, Zonag Lake in Hoh Xil experienced sudden drainage, the water eventually flowed into Yanhu Lake, which caused Yanhu Lake to continue to expand. The potential collapse of Yanhu Lake could directly threaten the operational safety of the adjacent Qinghai-Tibet Highway, Qinghai-Tibet Railway. To explore the implications of expanding lakes on the surrounding permafrost, we selected Hoh Xil Yanhu Lake on the Qinghai-Tibet Plateau to study the effect of lake expansion on permafrost degradation. The permafrost degradation in the Yanhu Lake basin from October 2017 to December 2022 was inverted using Sentinel-1 satellite image data and small baseline subset interferometry synthetic aperture radar(SBAS-In SAR) technology. Additionally, permafrost degradation from February 2007 and February 2010 was analyzed using advanced land observing satellite phased array-type L-band synthetic aperture radar(ALOS PALSAR) satellite images and differential interferometric synthetic aperture radar(D-In SAR) technique. The results showed that the permafrost around Yanhu Lake experienced accelerated degradation. Prior to the expansion of Yanhu Lake, the average annual deformation rate along the line of sight(LOS) direction was 6.7 mm/yr. After the expansion, the rate increased to 20.9 mm/yr. The integration of spatial-temporal distribution maps of surface subsidence, Wudaoliang borehole geothermal data, meteorological data, Yanhu Lake surface area changes, and water level changes supports the assertion that the intensified permafrost degradation could be attributed to lake expansion rather than the rising air temperature. Furthermore, permafrost degradation around Yanhu Lake could impact vital infrastructure such as the adjacent Qinghai-Tibet Highway and Qinghai-Tibet Railway.

关键词： Lake expansion SBAS-InSAR D-InSAR Permafrost deformation Qinghai-Tibet Plateau

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考虑海缆实际载流量的海上风电集电系统拓扑优化

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中国电力 2024年第7期57卷 173-181页

作者：叶婧蔡俊文张磊周广浩何杰辉翟学三峡大学电气与新能源学院湖北宜昌443002 梯级水电站运行与控制湖北省重点实验室(三峡大学) 湖北宜昌443002 国网浙江省电力有限公司台州供电公司浙江台州318000 湖北省电力勘测设计院有限公司湖北武汉430040

海缆实际载流量是海缆选型的重要依据,在海上风电场集电系统拓扑优化中,考虑不同敷设区段海缆载流量存在的差异以及海缆多回路并联敷设时磁热效应对载流量的影响,对保障集电系统的安全性具有重要意义。首先,采用模糊C均值算法对风机进... 详细信息

海缆实际载流量是海缆选型的重要依据,在海上风电场集电系统拓扑优化中,考虑不同敷设区段海缆载流量存在的差异以及海缆多回路并联敷设时磁热效应对载流量的影响,对保障集电系统的安全性具有重要意义。首先,采用模糊C均值算法对风机进行聚类分区,将集电系统拓扑优化分解为分区内、外拓扑优化。然后,在分区内采用基于Voronoi图的拓扑搜索算法进行求解;在分区外拓扑优化中,考虑海缆瓶颈区段、回路数对载流量的影响,构建混合整数非线性优化模型,线性化后采用优化求解器GUROBI进行求解。最后,以某实际风电场为例进行仿真验证。结果表明,所提模型能保证海缆实际载流量始终大于海缆工作电流,可有效保障集电系统的安全性。

关键词：海上风电场集电系统拓扑优化载流量回路数

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Ultrasonic C-scan Detection for Stainless Steel Spot Welding Based on Wavelet Package Analysis

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Journal of Wuhan University of Technology(Materials Science) 2015年第3期30卷 580-585页

作者：刘静 XU Guocheng 徐德生 zhou guanghao FAN Qiuyue Key Laboratory of Automobile Materials of Ministry of Education and Department of Materials Science & Engineering Jilin University

An ultrasonic test of spot welding for stainless steel is conducted. Based on wavelet packet decomposition, the ultrasonic echo signal has been analyzed deeply in time - frequency domain, which can easily distinguish the nugget from the corona bond. The 2D C-scan images produced by ultrasonic C scan which contribute to quantitatively calculate the nugget diameter for the computer are further analyzed. The spot welding nugget diameter can be automatically obtained by image enhancement, edge detection and equivalent diameter algorithm procedure. The ultrasonic detection values in this paper show good agreement with the metallographic measured values. The mean value of normal distribution curve is 0.006 67, and the standard deviation is 0.087 11. Ultrasonic C-scan test based on wavelet packet signal analysis is of high accuracy and stability.

关键词： stainless steel spot welding ultrasonic test wavelet package analysis nugget diameter

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Progress in polymer solar cell

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Chinese Science Bulletin 2007年第2期52卷 145-158页

作者： LI LiGui LU guanghao YANG XiaoNiu zhou EnLe State Key Laboratory of Polymer Physics and Chemistry Changchun Institute of Applied Chemistry Chinese Academy of SciencesChangchun 130022 China

This review outlines current progresses in polymer solar cell. Compared to traditional silicon-based photovoltaic (PV) technology, the completely different principle of optoelectric response in the polymer cell results in a novel configuration of the device and more complicated photovoltaic generation proc-ess. The conception of bulk-heterojunction (BHJ) is introduced and its advantage in terms of mor-phology is addressed. The main aspects including the morphology of photoactive layer, which limit the efficiency and stability of polymer solar cell, are discussed in detail. The solutions to boosting up both the efficiency and stability (lifetime) of the polymer solar cell are highlighted at the end of this review.

关键词：太阳能电池聚合体硅薄膜稳定性

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不锈钢激光焊接头超声导波检测与质量评价技术

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电焊机 2024年第5期54卷 142-147,159页

作者：赵雪山段珍珍周广浩郑月生谷晓鹏中车长春轨道客车股份有限公司吉林长春130062 长春工程学院吉林长春130103 吉林大学吉林长春130022

半熔透型搭接激光焊工艺质量控制难度大,如何有效保证板层间的熔合宽度是开发和应用半熔透型搭接激光焊技术的关键。为此,开展薄板焊接接头超声导波检测方法研究,研发接头内部熔合宽度检测与评估系统,通过对超声导波信号时、频域特征分... 详细信息

半熔透型搭接激光焊工艺质量控制难度大,如何有效保证板层间的熔合宽度是开发和应用半熔透型搭接激光焊技术的关键。为此,开展薄板焊接接头超声导波检测方法研究,研发接头内部熔合宽度检测与评估系统,通过对超声导波信号时、频域特征分析,确定能够表现接头内部熔合状态的信号特征值,并以此建立能够有效区分不同焊接质量的评价模型,从而实现不锈钢半熔透型搭接激光焊接头内部熔宽的在线检测。研究结果表明,以超声导波时域信号上最大归一化幅值、频域上第一波峰和第二波峰的峰值为输入信息,采用BP神经网络算法进行分类预测,能够有效识别未熔合、熔合宽度不足、熔合宽度合格等连接状态,预测准确率可达94.4%。

关键词：激光焊接头超声导波无损检测质量评价

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青藏高原热融滑塌研究进展综述

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冰川冻土 2024年第4期46卷 1135-1155页

作者：罗炳楠刘文惠谢昌卫刘海瑞郝君明周广浩李卿鹏李晴青海大学地质工程学院青海西宁810016 中国科学院西北生态环境资源研究院冰冻圈科学国家重点实验室甘肃兰州730000 青海大学生态环境工程学院青海西宁810016 兰州理工大学土木工程学院甘肃兰州730050

在全球气候变暖的大背景和人类活动产生的增温效应影响下,青藏高原多年冻土加速退化,致使热融滑塌频发。这一现象不仅直接影响区域生态环境,还对工程建筑物的稳定性造成潜在威胁。本文旨在通过综述青藏高原多年冻土区热融滑塌的研究进展... 详细信息

在全球气候变暖的大背景和人类活动产生的增温效应影响下,青藏高原多年冻土加速退化,致使热融滑塌频发。这一现象不仅直接影响区域生态环境,还对工程建筑物的稳定性造成潜在威胁。本文旨在通过综述青藏高原多年冻土区热融滑塌的研究进展,概括热融滑塌的形成机理、提取方法、发育特征、影响机理及其对环境和工程的影响等,以期为热融灾害防治和气候变化评估预测提供科学依据。总结得出:热融滑塌的形成是多种复杂因子作用并长期积累的结果,常造成溯源侵蚀。其发育形状各异,以长条形、支岔形、多头舌为主。热融滑塌在空间上呈不均匀分布,集中在青藏工程走廊。其空间分布主要受地形与冻土条件影响。此外,热融滑塌会改变土壤结构和理化过程,对区域碳循环产生影响,进而增加全球或区域性的温室气体排放。监测热融滑塌通常采用高空间分辨率遥感影像解译与无人机实地验证相结合的方式。目前研究中多结合Planet Cube Sat影像与深度学习算法,实现对大范围冻土区热融滑塌的自动识别与制图。Deep Lab V3+等深度学习模型在未来大范围热融滑塌研究中有很好的应用前景。随着我国青藏高原地区工程建设和生态环境保护的需求增长,探究热融滑塌的形成机理、发育特征、影响机理及其对环境和工程的影响,可为青藏高原工程规划、热融灾害防治、环境保护提供理论基础和科学依据。

关键词：青藏高原热融滑塌发育特征驱动机制环境和工程影响

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Factors hindering the degradation of pharmaceuticals from human urine in an iron-activated persulfate system

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Journal of Environmental Sciences 2024年第1期135卷 130-148页

作者： Yiruiwen Xie Dao Guan Yangfan Deng Yugo Sato Yu Luo guanghao Chen Department of Civil and Environmental Engineering Water Technology LabHong Kong Branch of Chinese National Engineering Research Center for Control&Treatment of Heavy Metal PollutionThe Hong Kong University of Science&TechnologyHong Kong 999077China

This study investigated the degradation of clofibric acid(CFA),bezafibrate(BZF),and sulfamethoxazole(SMX)in synthetic human urine using a novel mesoporous iron powderactivated persulfate system(mFe-PS system),and identified the factors limiting their degradation in synthetic human urine.A kinetic model was established to expose the radical production in various reaction conditions,and experiments were conducted to verify the modeling *** the phosphate-containing mFe-PS system,the 120 min removal efficiency of CFA decreased from 95.1%to 76.6%as the phosphate concentration increased from 0.32 to 6.45 mmol/L,but recovered to 90.5%when phosphate concentration increased to 16.10 mmol/***,the increased concentration of phosphate from 0.32 to 16.10mmol/L reduced the BZF degradation efficacy from 91.5%to 79.0%,whereas SMX removal improved from 37.3%to 62.9%.The m Fe-PS system containing(bi)carbonate,from 4.20 to166.70 mmol/L,reduced CFA and BZF removal efficiencies from 100%to 76.8%and 80.4%,respectively,and SMX from 83.5%to 56.7%within a 120-min reaction *** addition,alkaline conditions(pH≥8.0)inhibited CFA and BZF degradations,while nonacidic pH(pH≥7.0)remarkably inhibited SMX *** of the kinetic model indicated the formation of phosphate(H_(2)PO_(4)^(·)/HPO_(4)^(·-))and/or carbonate radicals(CO_(3)^(·-))could limit pharmaceutical *** transformation products(TPs)of the pharmaceuticals revealed more incompletely oxidized TPs occurred in the phosphate-and(bi)carbonate-containing m Fe-PS systems,and indicated that H_(2)PO_(4)^(·)/HPO_(4)^(·-)mainly degraded pharmaceuticals via a benzene ring-opening reaction while CO_(3)^(·-)preferentially oxidized pharmaceuticals via a hydroxylation reaction.

关键词： Pharmaceutical degradation Human urine Iron-activated persulfate system Phosphate radicals Carbonate radicals Transformation products

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Rapid ultrasonic C-scan on image test for spot welding based interpolation

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China Welding 2014年第4期23卷 37-43页

作者：刘静徐国成史延利周广浩谷晓鹏 Key Laboratory of Automobile Materials of Ministry of Education andDepartment of Materials Science & Engineering Jilin University Changchun 130022.

In this paper, ultrasonic C-scan test of spot welds for stainless steel has been studied. It is concluded that large scanning step length contributes to high testing efficiency, however, the low-resolution C-scan image generated cannot be used to assess spot welding quality reliably. Based on bicubic image interpolation, the C-scan image in low resolution with the large step length 1 000 ~xm is subdivided and reconstructed. By this means, the C-scan image resolution is greatly enhanced and testing results obtained are satisfactory, realizing rapid assessment of spot welds. The results of rapid ultrasonic C-scan test fit the actual metallographic measured value well. Mean value of normal distribution of error statistics is O. 006 67, and the standard deviation is O. 087 11. Rapid ultrasonic C-scan test based on image interpolation is of high accuracy and excellent stability.

关键词： rapid ultrasonic test C-scan test image interpolation spot welds nugget diameter

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计及暂态频率稳定约束的同步惯量经济价值评估

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电力系统保护与控制 2023年第8期51卷 50-62页

作者：叶婧杨莉张磊周广浩蔡俊文三峡大学电气与新能源学院湖北宜昌443002 梯级水电站运行与控制湖北省重点实验室(三峡大学) 湖北宜昌443002

高渗透率新能源接入系统后,保障系统具有充足的在线惯量是维持系统频率安全稳定的关键,同时建立惯性辅助服务市场是解决该问题的有效手段。因此,将同步惯性响应纳入有偿服务,搭建考虑系统最低同步惯量需求约束的定价出清模型,并提出离... 详细信息

高渗透率新能源接入系统后,保障系统具有充足的在线惯量是维持系统频率安全稳定的关键,同时建立惯性辅助服务市场是解决该问题的有效手段。因此,将同步惯性响应纳入有偿服务,搭建考虑系统最低同步惯量需求约束的定价出清模型,并提出离散变量松弛化的方法,将出清模型转化为凸优化问题。然后,基于边际成本定价法和拉格朗日对偶原理,以最低同步惯量需求约束对应的影子价格来评估其经济价值,为惯性服务定价。最后,以改进的IEEE 39节点系统和IEEE 118节点系统为例,对同步惯量影子价格的存在机理、数值影响因素以及同步机组收益进行分析讨论。结果表明,含高比例新能源系统具有建设惯性辅助服务市场的必要性和迫切性。所提方法和仿真结论为惯性服务市场化提供了参考性意见。

关键词：惯性辅助服务市场最低同步惯量需求频率稳定边际成本定价影子价格

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Thylakoid engineered M2 macrophage for sonodynamic effect promoted cell therapy of early atherosclerosis

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Nano Research 2024年第4期17卷 2919-2928页

作者： guanghao Wu Changwen Mu Qianru Zhao Yao Lei Ran Cheng Weidong Nie Jiamin Qu Yuping Dong Ruili Yang Haiyan Xie State Key Laboratory of Natural and Biomimetic Drugs School of Pharmaceutical SciencesChemical Biology CenterPeking UniversityBeijing 100191China School of Materials Science and Engineering Beijing Institute of TechnologyBeijing 100081China School of Life Science Beijing Institute of TechnologyBeijing 100081China School of Stomatology Peking UniversityBeijing 100081China

Atherosclerosis is the most common cause of cardiovascular diseases that contribute to the major morbidity worldwide,but still lacking of effective treatment ***,a hybrid cell is constructed for the sonodynamic effect promoted cell therapy of early atherosclerosis by fusing M2 macrophages with thylakoid(TK)*** systemic administration,the obtained TK-M2 actively accumulates in the early atherosclerotic plaques,wherein M2 macrophages relieve the cholesterol accumulation and the inflammation in the foam ***,the TK membranes decorated on the M2 macrophages exhibit both type I and type II sonodynamic effects under ultrasound(US)activation,inducing the direct apoptosis of foam *** cooperation of M2 and TK leads to significant outcome in eliminating atherosclerotic plaques without obvious side-effects,providing a new avenue for atherosclerosis treatment.

关键词： atherosclerosis thylakoid ultrasound M2 macrophage

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