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High-speed GaN-based laser diode with modulation bandwidth exceeding 5 GHz for 20 Gbps visible light communication

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Photonics Research 2024年第6期12卷 1186-1193页

作者： JUNFEI WANG JUNHUI HU chaoWEN GUAN YUQI hou ZENGYI XU LEIHAO SUN YUE WANG YUNING Zhou BOON S.OOI JIANYANG SHI ZIWEI LI JUNWEN ZHANG NAN CHI SHAOHUA YU chao SHEN School of Information Science and Technology Fudan UniversityShanghai 200433China Peng Cheng Laboratory Shenzhen 518000China ZGC Institute of Ubiquitous-X Innovation and Applications Beijing 100876China Photonics Laboratory King Abdullah University of Science and Technology(KAUST)Thuwal 23955-6900Saudi Arabia

Visible light communication(VLC)based on laser diodes demonstrates great potential for high data rate maritime,terrestrial,and aerial wireless data ***,we design and fabricate high-speed blue laser diodes(LDs)grown on c-plane gallium nitride(GaN)*** was achieved through active region design and miniaturization toward a narrow ridge waveguide,short cavity length,and single longitudinal mode Fabry–Perot laser *** fabricated mini-LD has a low threshold current of 31 mA and slope efficiency of 1.02 W/A.A record modulation bandwidth of 5.9 GHz(−3dB)was measured from the *** the developed mini-LD as a transmitter,the VLC link exhibits a high data transmission rate of 20.06 Gbps adopting the bit and power loading discrete multitone(DMT)modulation *** corresponding bit error rate is 0.003,satisfying the forward error correction *** demonstrated GaN-based mini-LD has significantly enhanced data transmission rates,paving the path for energy-efficient VLC systems and integrated photonics in the visible regime.

关键词： communication diode waveguide

Four 14(13→12)‑Abeolanostane Triterpenoids with 6/6/5/6‑Fused Ring System from the Roots of Kadsura coccinea

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Natural Products and Bioprospecting 2019年第3期9卷 165-173页

作者： hou-chao Xu Kun Hu Han-Dong Sun Pema-Tenzin Puno State Key Laboratory of Phytochemistry and Plant Resources in West China Kunming Institute of BotanyChinese Academy of Sciencesand Yunnan Key Laboratory of Natural Medicinal ChemistryKunming 650201People’s Republic of China University of Chinese Academy of Sciences Beijing 100049People’s Republic of China

Four new rearranged 6/6/5/6-fused lanostane-type triterpenoids,kadcoccitanes A-D(1-4),were isolated from the roots of Kadsura coccinea,and their structures were mainly elucidated by comprehensive analysis of their spectroscopic ***,the structure of 1 was ambiguously verifed by single-crystal X-ray difraction,while the structure of 2,which features a novel 8,16-epoxy motif,was validated by quantum chemical calculation of NMR parameters and ECD ***,1 and 4 were found to exhibited anticoagulant activity,while 3 and 4 were found to possess anti-platelet aggregation activity.

关键词： Kadsura coccinea Lanostane triterpenoid NMR computation Anti-platelet aggregation Anticoagulant

夹层旋转扁壳轴对称非线性稳定的样条函数解法

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天津大学学报 2011年第8期44卷 732-736页

作者：侯朝胜天津大学建筑工程学院天津300072

以三次B样条函数为试函数,用配点法计算夹层旋转扁壳非线性稳定.荷载为多项式型的分布荷载或均布边缘力矩.夹层壳采用Reissner模型.得到了夹层圆锥壳、球壳、余弦壳收敛的上、下临界荷载.与其他方法的结果作了比较.结果表明样条配点法... 详细信息

以三次B样条函数为试函数,用配点法计算夹层旋转扁壳非线性稳定.荷载为多项式型的分布荷载或均布边缘力矩.夹层壳采用Reissner模型.得到了夹层圆锥壳、球壳、余弦壳收敛的上、下临界荷载.与其他方法的结果作了比较.结果表明样条配点法具有计算精度高、荷载收敛范围大、编写程序通用的优点.

关键词：夹层壳旋转扁壳非线性稳定样条配点法

有中心集中荷载作用的任意变厚度的旋转扁薄壳的非线性弯曲

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天津大学学报 2011年第3期44卷 210-214页

作者：侯朝胜天津大学建筑工程学院天津300072

中心集中荷载作用的变厚度圆板或旋转扁壳的轴对称非线性弯曲,迄今鲜见研究成果.取三次B样条函数和对数函数为试函数,用配点法计算任意变厚度圆板的大挠度和旋转扁壳的非线性稳定.计算了中心集中荷载作用的圆板及它和反向均布荷载同时... 详细信息

中心集中荷载作用的变厚度圆板或旋转扁壳的轴对称非线性弯曲,迄今鲜见研究成果.取三次B样条函数和对数函数为试函数,用配点法计算任意变厚度圆板的大挠度和旋转扁壳的非线性稳定.计算了中心集中荷载作用的圆板及它和反向均布荷载同时作用圆板且其中心挠度为零的特殊情形.给出了中心集中荷载作用下,线性或多项式型变厚度的圆锥壳、球壳或四次多项式型旋转壳的上、下临界荷载.等厚度圆板和球壳的计算结果同其他方法的结果做了比较.结果表明样条配点法有更高的精度和更大的荷载收敛范围.

关键词：旋转扁壳任意变厚度非线性稳定中心集中荷载复合荷载样条配点法

TyG指数与2型糖尿病非增殖性视网膜病变的相关性

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中国临床研究 2023年第5期36卷 656-660页

作者：焦聪侯超李蓉西安医学院全科医学院陕西西安710068 西安医学院第一附属医院眼科陕西西安710077

目的探讨三酰甘油葡萄糖乘积指数(TyG)与2型糖尿病(T2DM)非增殖性视网膜病变(NPDR)严重程度的相关性。方法回顾性收集2018年1月至2022年6月西安医学院第一附属医院收治的235例T2DM患者的临床资料及实验室检查结果,根据眼底情况分为无糖... 详细信息

目的探讨三酰甘油葡萄糖乘积指数(TyG)与2型糖尿病(T2DM)非增殖性视网膜病变(NPDR)严重程度的相关性。方法回顾性收集2018年1月至2022年6月西安医学院第一附属医院收治的235例T2DM患者的临床资料及实验室检查结果,根据眼底情况分为无糖尿病性视网膜病变(DR)组(NDR组,75例)、Ⅰ期DR组(77例)、Ⅱ期DR组(59例)、Ⅲ期DR组(24例)。计算TyG指数并比较组间差异;分析影响NPDR的危险因素,以及TyG指数对NPDR的预测价值。结果NDR组与Ⅰ、Ⅱ、Ⅲ期DR组的TyG指数差异有统计学意义(P<0.05)。Logistic回归分析显示,影响NPDR的危险因素为T2DM病程、收缩压、血肌酐(Scr)、三酰甘油(TG)、空腹血糖(FPG)。ROC曲线分析显示,TyG指数预测NPDR的曲线下面积显著大于TG[0.705(0.639~0.771)vs 0.656(0.585~0.726),Z=2.657,P=0.008]。结论TyG指数可综合反映NPDR的发生情况,在预测NPDR方面,TyG指数较TG更优,其可作为预测NPDR发生的生物学指标。

关键词： 2型糖尿病糖尿病性视网膜病变,非增殖性视网膜病变程度三酰甘油葡萄糖乘积指数

Fluorescence sensor based on IFE between AEP@UCNPs and oxTMB for the determination of Cdin paddy rice combined with HRP enzyme inhibition mechanism

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Food Science and Human Wellness 2024年

作者： Haizhen Ding Shuai hou Siqi Zhao Liping Guo Ao Sun Qiuhui Hu Leiqing Pan Qiang Liu chao Ding College of Food Science and Technology Nanjing Agricultural University Collaborative Innovation Center for Modern Grain Circulation and Safety Key Laboratory of Grains and Oils Quality Control and Processing College of Food Science and Engineering Nanjing University of Finance and Economics

Cadmium ion (Cd2+) detection technology plays a prominent role in food safety and human health. Herein， we designed and constructed an 2-aminoethyl dihydrogen phosphate (AEP)@upconversion nanoparticles (UCNPs) fluorescence sensor for quantitative detection of Cd2+in paddy rice based on Inner filter effect (IFE) combined with enzyme inhibition mechanism. The AEP modification UCNPs can offer a stable fluorescence donor at 658 nm and be quenched by the oxidized tetramethylbenzidine (oxTMB) catalyzed by horseradish peroxidase (HRP) enzymes. Without addition of Cd2+， the fluorescence of AEP@UCNPs fluorescence sensor was weaken due to the IFE between AEP@UCNPs and oxTMB. With addition of Cd2+， HRP enzyme activity was inhibited by Cd2+， leading to the decreased oxTMB， resulting in the enhance upconversion fluorescence intensity. As a result， the fluorescence intensity signal at 658 nm of the IFE-based AEP@UCNPs fluorescence sensor increased linearly with the increase in Cd2+in a wide range from 0.5 μmol/L to 6? μmol/L and the limit of detection (LOD) was 24.6 nmol/L. In addition， our proposed IFE-based AEP@UCNPs fluorescence sensor can achieve Cd2+detection in paddy rice in 30 min.

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Compound extreme inundation risk of coastal wetlands caused by climate change and anthropogenic activities in the Yellow River Delta,China

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Advances in Climate Change Research 2024年第1期15卷 134-147页

作者： Xiao-Li WANG Ai-Qing FENG Xi-Yong hou Qing-Chen chao Bai-Yuan SONG Yu-Bin LIU Qi-Guang WANG He XU Yu-Xin ZHANG Dong Li Li-Jie DONG Yu GUO CAS Key Laboratory of Coastal Environmental Processes and Ecological Remediation Yantai Institute of Coastal Zone ResearchChinese Academy of SciencesYantai 264003China Shandong Key Laboratory of Coastal Environmental Processes Yantai 264003China China Meteorological Administration Key Laboratory for Climate Prediction Studies National Climate CentreBeijing 100081China Tongji Urban Planning Design Research Institute Shanghai 200092China School of Geography and Tourism Qilu Normal UniversityJinan 250200China China Meteorological Administration Training Centre China Meteorological AdministrationBeijing 10008China University of Chinese Academy of Sciences Beijing 100049China Marine Science and Technology College Zhejiang Ocean UniversityZhoushan 316022China

The coastal wetlands of the Yellow River Delta(YRD)in China are crucial for their valuable resources,environmental significance,and economic ***,these wetlands are also vulnerable to the dual threats of climate change and human *** substantial attention to the historical shifts in YRD's coastal wetlands,uncertainties remain regarding their future trajectory in the face of compound risks from climate change and anthropogenic *** on a range of remote sensing data sources,this study undertakes a comprehensive investigation into the evolution of YRD's coastal wetlands between 2000 and ***,the potential fate of coastal wetlands is thoroughly analyzed through the Land Use/Cover Change(LUCC)simulation using System Dynamic-Future Land Use Simulation(SD-FLUS)model and the extreme water levels projection integrated future sea-level rise,storm surge,and astronomical high tide in 2030,2050,and 2100 under scenarios of SSP1-2.6,SSP2-4.5,and *** revealed that YRD's coastal wetlands underwent a marked reduction,shrinking by 1688.72 km²from 2000 to *** decline was mostly attributed to the substantial expansion in the areas of artificial wetlands(increasing by 823.78 km2),construction land(increasing by 767.71 km²),and shallow water(increasing by 274.58 km²).Looking ahead to 2030-2100,the fate of coastal wetlands appears to diverge based on different *** the SSP1-2.6 scenario,the area of coastal wetland is projected to experience considerable *** contrast,the SSP5-8.5 scenario anticipates a notable decrease in coastal *** to the inundated area suffered from the current extreme water levels,the study projects a decrease of 6.8%-10.6%in submerged coastal wetlands by 2030 and 9.4%-18.2%by 2050 across all *** 2100,these percentages are projected to decrease by 0.4%(SSP2-4.5)and 27.1%(SSP5-8.5),but increase by 35.7%(SSP1-2.6).Results suggest that coastal wetlands in th

关键词： Climate change Anthropogenic activities Compound extreme risk Coastal wetlands Yellow River Delta

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城市群功能分工对区域协调发展的影响研究

西部金融 2023年第4期 69-78页

作者：侯超西安科技大学管理学院陕西西安710600

城市群功能分工与区域协调发展作为中国推动区域发展的重大战略举措,两类政策能否达到“珠联璧合”的实施效果,对中国区域发展具有重要意义。为探究城市群功能分工对区域协调发展的影响,本文构建空间计量模型及面板门槛模型进行系统考... 详细信息

城市群功能分工与区域协调发展作为中国推动区域发展的重大战略举措,两类政策能否达到“珠联璧合”的实施效果,对中国区域发展具有重要意义。为探究城市群功能分工对区域协调发展的影响,本文构建空间计量模型及面板门槛模型进行系统考察。研究结果显示:(1)中国区域发展协调度存在显著的空间相关性;(2)城市群功能分工与区域协调发展之间存在显著的倒“U”型关系,即随着功能分工的不断深化,区域发展协调度先上升后下降;(3)城市群功能分工对区域协调发展的空间溢出效应大于本地效应;(4)在投资产出率、科技水平、区域开放度、人均固定资产投资四种机制调节下,城市群功能分工对区域协调发展的影响存在门槛效应。

关键词：城市群功能分工区域协调发展空间溢出效应门槛效应

融合知识的文博领域低资源命名实体识别方法研究

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北京大学学报（自然科学版） 2024年第1期60卷 13-22页

作者：李超侯霞乔秀明北京信息科技大学计算机学院北京100192

文物数据的实体嵌套问题明显,实体边界不唯一,且文博领域已标注数据极度缺乏,导致该领域命名实体识别性能较低。针对这些问题,构建一个可用于文物命名实体识别的数据集FewRlicsData,提出一种融合知识的文博领域低资源命名实体识别方法Re... 详细信息

文物数据的实体嵌套问题明显,实体边界不唯一,且文博领域已标注数据极度缺乏,导致该领域命名实体识别性能较低。针对这些问题,构建一个可用于文物命名实体识别的数据集FewRlicsData,提出一种融合知识的文博领域低资源命名实体识别方法RelicsNER。该方法将类别描述信息的语义知识融入文物文本中,使用基于跨度的方式进行解码,用于改善实体嵌套问题,并采用边界平滑的方式缓解跨度识别模型的过度自信问题。与基线模型相比,该方法在FewRlicsData数据集上的F1值有所提升,在文博领域命名实体识别任务中取得较好的性能。在公开数据集OntoNotes 4.0上的实验结果证明该方法具有较好的泛化性,同时在数据集OntoNotes 4.0和MSRA上进行小规模数据实验,性能均高于基线模型,说明所提方法适用于低资源场景。

关键词：文博领域命名实体识别知识融合注意力机制

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