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Distribution and invasion of Spartina alterniflora within the Jiaozhou Bay monitored by remote sensing image

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Acta Oceanologica Sinica 2022年第6期41卷 31-40页

作者： Jianbu Wang Zhaoyang Lin Yuanqing Ma Guangbo Ren Zijun Xu Xiukai Song Yi Ma Andong Wang Yajie Zhao Laboratory of Marine Physics and Remote Sensing First Institute of OceanographyMinistry of Natural ResourcesQingdao 266061China School of Information and Electrics Beijing Institute of TechnologyBeijing 100081China Shandong Marine Resources and Environment Research Institute Shandong Provincial Key Laboratory of Restoration for Marine EcologyYantai 264006China North China Sea Environmental Monitoring Center State Oceanic AdministrationQingdao 266033China Shandong Yellow River Delta National Nature Reserve Administration Committee Dongying 257091China

Spartina alterniflora as an alien invasive plant,poses a serious threat to the ecological functions of the coastal wetland of the Jiaozhou Bay.As of 2019,the distribution area of S.alterniflora in the Jiaozhou Bay has reached more than 500 hm^(2).For this reason,combined with field surveys,remote sensing monitoring of the invasion S.alterniflora in the Jiaozhou Bay has been carried out.To accurately identify S.alterniflora within the Jiaozhou Bay coastal wetland,we used a new method which is an implement of deep convolutional neural network,and by which we got a higher accuracy than the traditional method.Based on distribution of S.alterniflora extracted by the proposed method,the temporal and spatial distribution characteristics of S.alterniflora were analyzed.And then combined with environmental factors,the invasion mechanism of S.alterniflora in the Jiaozhou Bay was analyzed in detail.From the monitoring results,it can be seen that S.alterniflora in Jiaozhou Bay is mainly distributed in the beaches near the Yanghe River Estuary and its southern side,the Dagu River Estuary and the Nügukou.Spartina alterniflora first broke out near the Yanghe River Estuary and gradually spread to the tidal flats near the Nügukou.The Dagu River Estuary is dominated by S.anglica,whose area has not changed much over the years,and a small amount of S.alterniflora has invaded later.

关键词： Spartina alterniflora remote sensing coastal wetland deep residual network

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爆后岩石裂隙结构可视化及定量表征方法

煤炭学报 2024年第3期49卷 1388-1402页

作者：王雁冰王兆阳付代睿罗林中国矿业大学(北京)力学与土木工程学院北京100083 中国矿业大学(北京)隧道工程灾变防控与智能建养全国重点实验室北京100083

爆后岩石破坏特征的定量表征一直是工程爆破领域急需解决的关键问题,爆后岩石裂纹萌生、扩展演化直至贯通的过程是导致岩石破裂的主要原因。为了研究被爆岩石内部裂纹扩展和断裂模式的演化过程,利用工业CT对爆后岩石进行扫描观测,通过... 详细信息

爆后岩石破坏特征的定量表征一直是工程爆破领域急需解决的关键问题,爆后岩石裂纹萌生、扩展演化直至贯通的过程是导致岩石破裂的主要原因。为了研究被爆岩石内部裂纹扩展和断裂模式的演化过程,利用工业CT对爆后岩石进行扫描观测,通过图像堆栈矢量化处理构建岩石三维裂隙模型,并对裂纹结构特征参数进行统计分析,定量化表征岩石破坏程度及裂纹扩展情况。结合数值模拟分析爆炸冲击波压力的衰减规律,通过SEM电镜扫描试验研究爆破过程中不同位置岩石的微观形貌特征,对比断口元素成分变化与断裂模式的关联机制。研究结果表明:用等效球体方法对岩体内不同尺度裂隙结构进行统计分析,微裂隙数目多且分布均匀,主裂隙体积大且连通性较好。随着裂隙等效球体直径的增加,裂隙表面积和体积整体上呈上升趋势;三维重构裂隙结构中裂隙率可以表征岩石局部裂纹扩展特征,爆炸近区裂隙率和三维分形维数远大于爆炸中远区的裂隙率和分形维数,说明岩石破裂过程中裂隙扩展演化主要在此阶段进行;相较于爆炸中远区,爆炸近区冲击波压力峰值高且衰减速率慢,使得整个爆破过程岩石微观断裂模式变化较大,大致呈现出由沿晶断裂向穿晶断裂、脆性断裂向塑性破坏的方向进行,非金属元素质量的变化对于各阶段断裂模式转变具有显著影响,断裂模式转变区域非金属元素质量发生明显减小。随着爆破作用的减弱,岩石破裂逐渐趋于无序和紊乱,破裂时断口也不限于解理面和晶粒边界。

关键词：爆破机理工业CT扫描三维重构分形维数扫描电子显微镜能谱仪

Chemical vapor deposition growth of single-crystalline cesium lead halide microplatelets and heterostructures for optoelectronic applications

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Nano Research 2017年第4期10卷 1223-1233页

作者： Yiliu Wang Xun Guan Dehui Li Hung-Chieh Cheng Xidong Duan Zhaoyang Lin Xiangfeng Duan Department of Chemistry and Biochemistry University of California Los Angeles Los Angeles CA 90095 USA State Key Laboratory for Chemo/Biosensing and Chemometrics College of Chemistry and Chemical Engineering Hunan University Changsha 410082 China School of Materials Science and Engineering University of Science and Technology Beijing Beijing 100083 China Department of Materials Science and Engineering University of California Los Angeles Los Angeles CA 90095 USA California NanoSystems Institute University of California Los Angeles Los Angeles CA 90095 USA

Organic-inorganic hybrid halide perovskites, such as CH3NHgPbI3, have emerged as an exciting class of materials for solar photovoltaic applications; however, they are currently plagued by insufficient environmental stability. To solve this issue, all-inorganic halide perovskites have been developed and shown to exhibit significantly improved stability. Here, we report a single-step chemical vapor deposition growth of cesium lead halide （CsPbX3） microcrystals. Optical microscopy studies show that the resulting perovskite crystals predominantly adopt a square-platelet morphology. Powder X-ray diffraction （PXRD） studies of the resulting crystals demonstrate a highly crystalline nature, with CsPbC13, CsPbBr3, and CsPbI3 showing tetragonal, monoclinic, and orthorhombic phases, respectively. Scanning electron microscopy （SEM） and atomic force microscopy （AFM） studies show that the resulting platelets exhibit well-faceted structures with lateral dimensions of the order of 10-50 μm, thickness around 1 μm, and ultra-smooth surface, suggesting the absence of obvious grain boundaries and the single-crystalline nature of the individual microplatelets. Photoluminescence （PL） images and spectroscopic studies show a uniform and intense emission consistent with the expected band edge transition. Additionally, PL images show brighter emission around the edge of the platelets, demonstrating a wave-guiding effect in high-quality crystals. With a well-defined geometry and ultra-smooth surface, the square platelet structure can function as a whispering gallery mode cavity with a quality factor up to 2,863 to support laser emission at room temperature. Finally, we demonstrate that such microplatelets can be readily grown on a variety of substrates, including silicon, graphene, and other two-dimensional materials such as molybdenum disulfide, which can readily allow the construction of heterostructure optoelectronic devices, including a graphene/perovskite/ graphene vertically-stacked photodetector with photoresponsivity 〉 10^5 A/W. Th

关键词： chemical vapor deposition inorganic perovskite microplatelets photoluminescence optical cavity photodetection

Three-dimensional graphene membrane cathode for high energy density rechargeable lithium-air batteries in ambient conditions

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Nano Research 2017年第2期10卷 472-482页

作者： Xing Zhong Benjamin Papandrea Yuxi Xu Zhaoyang Lin Hua Zhang Yuan Liu Yu Huang Xiangfeng Duan Department of Chemistry and Biochemistry University of California Los Angeles Los Angeles CA 90095 USA California Nanosystems Institute University of California Los Angeles Los Angeles CA 90095 USA Department of Materials Science and Engineering University of California Los Angeles Los Angeles CA 90095 USA

Lithium-air batteries have attracted significant interest for applications in high energy density mobile power supplies, yet there are considerable challenges to the development of rechargeable Li-air batteries with stable cycling performance under ambient conditions. Here we report a three-dimensional （3D） hydrophobic graphene membrane as a moisture-resistive cathode for high performance Li-air batteries. The 3D graphene membrane features a highly interconnected graphene network for efficient charge transport, a highly porous structure for efficient diffusion of oxygen and electrolyte ions, a large specific surface area for high capacity storage of the insulating discharge product, and a network of highly tortuous hydrophobic channels for O2/H20 selectivity. These channels facilitate 02 ingression while retarding moisture diffusion and ensure excellent charge/ discharge cycling stability under ambient conditions. The membrane can thus enable robust Li-air batteries with exceptional performance, including a maximum cathode capacity that exceeds 5,700 mAh/g and excellent recharge cycling behavior （〉2,000 cycles at 140 mAh/g, and 〉100 cycles at 1,400 mAh/g）. The graphene membrane air cathode can deliver a lifetime capacity of 100,000-300,000 mAh/g, comparable to that of a typical lithium ion battery cathode. The stable operation of Li-air batteries with significantly improved single charge capacities and lifetime capacities comparable to those of Li-ion batteries may offer an attractive high energy density storage alternative for future mobile power supplies. These batteries may provide much longer battery lives and greatly reduced recharge frequency.

关键词： energy storage,graphene framework,three-dimensional（3D）-network,lithium air-battery,water resistive

矿物微-纳尺度硫同位素分析及在东营凹陷油气成藏的应用示范

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岩石学报 2024年第1期40卷 313-322页

作者：郝佳龙张刘平李照阳杨蔚林杨挺中国科学院地质与地球物理研究所地球与行星物理院重点实验室北京100029 中国科学院地质与地球物理研究所油气资源研究院重点实验室北京100029 防灾科技学院三河市065201

黄铁矿等硫化物离子探针硫同位素分析已经广泛应用在成矿机理、古环境重建、大气环境硫源示踪及行星演化等研究中。纳米离子探针(CAMECA Nano SIMS 50L)的使用将硫化物硫同位素分析空间分辨率提升到微纳尺度(1μm~100nm),实现了分辨率1~... 详细信息

黄铁矿等硫化物离子探针硫同位素分析已经广泛应用在成矿机理、古环境重建、大气环境硫源示踪及行星演化等研究中。纳米离子探针(CAMECA Nano SIMS 50L)的使用将硫化物硫同位素分析空间分辨率提升到微纳尺度(1μm~100nm),实现了分辨率1~2μm、精度0.5‰(1SD)的硫同位素点分析方法,分辨率100nm、精度1‰的硫同位素图像分析方法。为了进一步优化分析流程拓展纳米离子探针硫同位素的应用,本文系统比较了纳米离子探针微纳尺度硫同位素点分析方法、图像分析方法的各自特点及分析流程;并以东营凹陷北带沙四段黄铁矿为研究对象,联合采用了纳米离子探针硫同位素点分析和硫同位素图像分析手段,对黄铁矿微细结构进行分析,从而揭示了储层中黄铁矿成因及其油气成藏的指示意义。

关键词：纳米离子探针硫同位素空间分辨率东营凹陷同位素图像

One-step strategy to graphene/Ni（OH）2 composite hy- drogels as advanced three-dimensional supercapacitor electrode materials

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Nano Research 2013年第1期6卷 65-76页

作者： Yuxi Xu Xiaoqing Huang Zhaoyang Lin Xing Zhong Yu Huang Xiangfeng Duan Department of Chemistry and Biochemistry University of California Los Angeles California 90095 USA Department of Materials Science and Engineering University of California Los Angeles California 90095 USA California Nanosystems Institute University of California Los Angeles California 90095 USA

基于 Graphene 三维(3D ) 宏观的材料最近在电气化学的精力变换和存储由他们的令人激动的潜力的优点吸引了增加的兴趣。这里，我们报导灵巧的一步舞策略准备机械地强壮、电子上传导性的 graphene/Ni (哦) 有一个互连的多孔的网络的 2 合... 详细信息

基于 Graphene 三维(3D ) 宏观的材料最近在电气化学的精力变换和存储由他们的令人激动的潜力的优点吸引了增加的兴趣。这里，我们报导灵巧的一步舞策略准备机械地强壮、电子上传导性的 graphene/Ni (哦) 有一个互连的多孔的网络的 2 合成 hydrogels。没有增加任何另外的文件夹或传导性的添加剂，合成 hydrogels 直接被用作 3D supercapacitor 电极材料。包含 82 wt.% Ni 的优化合成 hydrogel (哦) 2 与优秀骑车在 40 mV/s (63% 电容保留) 以 5 mV/s 和 785 F/g 的扫描率展出了 1,247 F/g 的一个特定的电容稳定性。3D hydrogels 的能力极大地超过 graphene 表和 Ni 的物理混合物的(哦) 2 nanoplates (在 40 mV/s 的 309 F/g ) 。一样的策略也被使用制作 graphene 碳 nanotube/Ni (哦) 有进一步改进的特定的电容(在 5 mV/s 的 1,352 F/g ) 和率能力(在 40 mV/s 的 66% 电容保留) 的 2 第三的合成 hydrogels。这里获得的两合成 hydrogels 能交付高精力密度(43 和 47 Wh/kg，分别地) 并且力量密度(8 和 9 kW/kg，分别地) ，为 supercapacitor 应用使他们成为吸引人的电极材料。这研究打开一条新小径到功能的 3D graphene 的设计和制造合成材料，和罐头显著地包括精力存储并且在以外影响宽广区域。

关键词：复合水凝胶超级电容器导电石墨电极材料三维 Ni(OH)2 镍扫描速率

动脉阻塞性疾病患者血浆骨形态发生蛋白-4的表达变化及其与炎症和血管损伤的相关性

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中南大学学报（医学版） 2024年第2期49卷 279-285页

作者：张文娟胡敏杨林周志芳陈若虹刘朝阳中南大学湘雅二医院检验医学科长沙410011 中南大学湘雅二医院麻醉科长沙410011 中南大学湘雅二医院党委办公室长沙410011

目的:骨形态发生蛋白-4(bone morphogenentic protein-4,BMP4)在动脉粥样硬化(atherosclerosis,AS)的病理过程中具有重要调节作用,但相关的临床研究较少。本研究拟观察以AS为主要病理特点的动脉阻塞性疾病(arterial occlusive disease,ACD)患者血浆BMP4的表达情况,并分析血浆中BMP4与炎症因子和血管损伤标志物之间的相关性。方法:共招募38名诊断为ACD的患者(ACD组)和38名体检志愿者(对照组),抽取ACD组患者术前和对照组体检时的静脉血,比较2组血常规指标的差异。采用酶联免疫吸附试验(enzyme linked immunosorbent assay,ELISA)检测血浆中BMP4、肿瘤坏死因子α(tumor necrosis factor-α,TNF-α)、白细胞介素(interleukin,IL)-1β、IL-10及血管内皮钙黏蛋白(vascular endothelial cadherin,VE-cadherin)的表达变化,并进一步分析BMP4与以上各指标之间的相关性。结果:与对照组相比,ACD组患者血常规结果表现为中性粒细胞-淋巴细胞比值[neutrophil to lymphocyte ratio,NLR;1.63(1.26,1.91)vs 3.43(2.16,6.61)]和血小板-淋巴细胞比值[platelet to lymphocyte ratio,PLR;6.37(5.26,7.74)vs 15.79(7.97,20.53)]升高、淋巴细胞-单核细胞比值[lymphocyte to monocyte ratio,LMR;5.67(4.41,7.14)vs3.43(2.07,3.74)]下降(均P<0.05);ACD组患者血浆BMP4[581.26(389.85,735.64)pg/mL vs 653.97(510.95,890.43)pg/mL]、TNF-α[254.16(182.96,340.70)pg/mLvs293.29(238.90,383.44)pg/mL]及内皮标志物VE-cadherin[1.54(1.08,2.13)ng/mL vs 1.85(1.30,2.54)ng/mL]的水平均显著升高,而抗炎因子IL-10的水平显著下降[175.89(118.39,219.25)pg/mLvs135.92(95.80,178.04)pg/mL](均P<0.05)。2组间促炎因子IL-1β的差异无统计学意义[300.39(205.39,403.56)pg/mL vs 378.46(243.20,448.69)pg/mL;P=0.09]。相关分析结果表明:血浆BMP4水平与促炎因子IL-1β(r=0.35)、TNF-α(r=0.31)以及内皮标志物VE-cadherin(r=0.47)呈正相关,与抗炎因子IL-10呈负相关(r=-0.37;均P<0.01)。结论:ACD患者血浆BMP4的水平升高,且与患者的炎症水平和血管损伤程度具有相关性。

关键词：动脉阻塞性疾病骨形态发生蛋白-4 炎症血管损伤

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超深井套管卡瓦效应的拉伸极限载荷理论计算

西南石油大学学报（自然科学版） 2024年第2期46卷 155-163页

作者：练章华万智勇宋琳赵朝阳林铁军油气藏地质及开发工程全国重点实验室·西南石油大学四川成都610500 中国石油新疆油田分公司工程技术研究院新疆克拉玛依834000

针对新疆某油田超深井井口套管悬重过大,造成卡瓦牙对套管外壁齿入损伤,且累计损伤导致卡瓦悬挂器套管断裂失效的事故频繁,提出了“卡瓦效应的拉伸极限载荷”来评价井口卡瓦悬挂器夹持部分套管的强度设计,具体为基于第三强度理论和第四... 详细信息

针对新疆某油田超深井井口套管悬重过大,造成卡瓦牙对套管外壁齿入损伤,且累计损伤导致卡瓦悬挂器套管断裂失效的事故频繁,提出了“卡瓦效应的拉伸极限载荷”来评价井口卡瓦悬挂器夹持部分套管的强度设计,具体为基于第三强度理论和第四强度理论,分别建立了井口卡瓦悬挂器夹持套管的“卡瓦效应拉伸极限载荷”计算模型。计算结果表明,从安全角度评价套管强度,采用第三强度理论计算卡瓦悬挂器套管的卡瓦效应拉伸极限载荷更合理,但为更充分利用材料的力学性能,应采用第四强度理论进行评价,还得到在四通有限空间内,可以保证有较大的卡瓦效应拉伸极限载荷的最佳卡瓦半锥角为23°~25°,最佳卡瓦有效接触长度为135~145 mm。研究方法和结果将为卡瓦悬挂器井口套管的强度设计、各种安全施工作业等提供理论依据。

关键词：深井超深井卡瓦悬挂器套管断裂力学模型拉伸极限载荷

OBH-RSI:Object-Based Hierarchical Classification Using Remote Sensing Indices for Coastal Wetland

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Journal of Beijing Institute of Technology 2021年第2期30卷 159-171页

作者： Zhaoyang Lin Jianbu Wang Wei Li Xiangyang Jiang Wenbo Zhu Yuanqing Ma Andong Wang Beijing Key Laboratory of Fractional Signals and Systems Beijing Institute of TechnologyBeijing 100081China Laboratory of Marine Physics and Remote Sensing First Institute of OceanographyMinistry of Natural ResourcesQingdao 266061China Shandong Provincial Key Laboratory of Restoration for Marine Ecology Shandong Marine Resources and Environment Research InstituteYantai 264006China Shandong Yellow River Delta National Nature Reserve Administration Committee Dongying 257091China

With the deterioration of the environment,it is imperative to protect coastal wetlands.Using multi-source remote sensing data and object-based hierarchical classification to classify coastal wetlands is an effective method.The object-based hierarchical classification using remote sensing indices(OBH-RSI)for coastal wetland is proposed to achieve fine classification of coastal wetland.First,the original categories are divided into four groups according to the category characteristics.Second,the training and test maps of each group are extracted according to the remote sensing indices.Third,four groups are passed through the classifier in order.Finally,the results of the four groups are combined to get the final classification result map.The experimental results demonstrate that the overall accuracy,average accuracy and kappa coefficient of the proposed strategy are over 94%using the Yellow River Delta dataset.

关键词： Yellow River Delta vegetation index object-based hierarchical classification wetland multi-source remote sensing