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High-resolution Hyper-spectral Image Classification with Parts-based Feature and Morphology Profile in Urban Area

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Geo-Spatial Information Science 2010年第2期13卷 111-122页

作者： HUANG Yuancheng zhang Liangpei LI Pingxiang zhong Yanfei State Key Laboratory of Information Engineering in Surveying Mapping and Remote Sensing Wuhan University 129Luoyu Road Wuhan 430079 China

High-resolution hyper-spectral image (HHR) provides both detailed structural and spectral information for urban study. However, due to the inherent correlation between spectral bands and within-class variability in the data, the data processing of HHR is a challenging work. In this paper, based on spectral mixture analysis theory, a new stack of parts description features were extracted, and then incorporated with a stack of morphology based spatial features. Partially supervised constrained energy minimization (CEM) and unsupervised nonnegative matrix factorization (NMF) were used to extract the part-features. The joint features were then integrated by SVM classifier. The advantages of this method are the representation of physical composition of the urban area by the parts-features and the show of multi-scale structure information by morphology profiles. Experiments with an airborne hyper-spectral data flightline over the Washington DC Mall were performed, and the performance of the proposed algorithm was evaluated in comparison with well-known nonparametric weighted feature extraction (NWFE) and feature selection method. The results shown that the proposed features-joint scheme consistently outperforms the traditional methods, and so can provide an effective option for processing HHR data in urban area.

关键词： parts-features CEM NMF morphology profiles hyper-spectral image urban classification

恒定法向刚度条件下吸能锚杆锚固节理岩体剪切特性试验研究

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岩石力学与工程学报 2024年第4期43卷 999-1012页

作者：韩观胜陈志靖李博周宇丁书学钟振绍兴文理学院浙江省岩石力学与地质灾害重点实验室浙江绍兴312000 同济大学地下建筑与工程系上海200092 河南理工大学土木工程学院河南焦作454003

为研究深部岩体工程即恒定法向刚度(CNS)边界条件下吸能锚杆的锚固效果及锚固节理抗剪性能,开展CNS边界条件下吸能锚杆锚固类岩石节理的剪切试验,探究节理面粗糙度(JRC)及锚固深度(h)对类岩石节理剪切应力(τ)、法向位移(δ_(n))、法向... 详细信息

为研究深部岩体工程即恒定法向刚度(CNS)边界条件下吸能锚杆的锚固效果及锚固节理抗剪性能,开展CNS边界条件下吸能锚杆锚固类岩石节理的剪切试验,探究节理面粗糙度(JRC)及锚固深度(h)对类岩石节理剪切应力(τ)、法向位移(δ_(n))、法向应力(σ_(n))、节理面破坏特征、锚杆变形特征的影响规律。结果表明:吸能锚杆可有效提高深部岩体锚固节理的屈服强度及剪切强度,且其提高幅度随着JRC的增大呈现出逐渐增加的趋势,其剪切应力在弹性阶段后产生应力硬化现象。而节理面剪切磨损面积占比随JRC的增加逐渐增大,锚杆的施加使其上涨了20.88%~109.21%。随着锚固深度的增加,节理面的剪切应力、法向位移、法向应力和剪切磨损面积占比均呈现出先增大后减小的趋势,当锚固深度为80 mm时各项指标参数最优,此时锚杆塑性变形段的锚固作用可充分发挥。研究成果为深部节理岩体支护作业的减能增效提供了重要理论支撑。

关键词：岩石力学节理面粗糙度锚固深度吸能锚杆恒定法向刚度剪切特性

依托咪酯调节cAMP/PKA/CREB信号通路对OGD/R诱导的神经元损伤的影响

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中国煤炭工业医学杂志 2024年第1期27卷 107-112页

作者：钟祖凌古学东易小波张勇中国人民解放军西部战区总医院四川省成都市610000

目的探究依托咪酯(Eto)调节环磷酸腺苷(cAMP)/蛋白激酶A(PKA)/cAMP反应元件结合蛋白(CREB)信号通路对糖氧剥夺/复氧(OGD/R)诱导的神经元损伤的影响。方法将海马神经元细胞HT22随机分为对照组、模型组、Eto低、中、高剂量组、抑制剂组。... 详细信息

目的探究依托咪酯(Eto)调节环磷酸腺苷(cAMP)/蛋白激酶A(PKA)/cAMP反应元件结合蛋白(CREB)信号通路对糖氧剥夺/复氧(OGD/R)诱导的神经元损伤的影响。方法将海马神经元细胞HT22随机分为对照组、模型组、Eto低、中、高剂量组、抑制剂组。MTT法计算细胞增殖抑制率,筛选Eto最佳干预浓度;EdU、流式细胞术分别检测细胞增殖、凋亡;ELISA法检测细胞中cAMP、白细胞介素-6(IL-6)、肿瘤坏死因子(TNF-α)水平;全自动生化分析仪检测细胞中乳酸脱氢酶(LDH)、丙二醛(MDA)、谷胱甘肽过氧化物酶(GSH-Px)水平;Western blot方法检测细胞中增殖细胞核抗原(PCNA)、Bcl-2相关X蛋白(Bax)、细胞抗凋亡因子B淋巴细胞瘤-2(Bcl-2)及cAMP/PKA/CREB信号通路蛋白表达。结果与对照组比较,模型组HT22细胞EdU阳性细胞率、cAMP、GSH-Px、PCNA、Bcl-2、p-PKA/PKA、p-CREB/CREB表达显著降低,凋亡率、IL-6、TNF-α、LDH、MDA、Bax表达显著升高(P<0.05);与模型组比较,Eto低、中、高剂量HT22细胞EdU阳性细胞率、cAMP、GSH-Px、PCNA、Bcl-2、p-PKA/PKA、p-CREB/CREB表达显著升高,凋亡率、IL-6、TNF-α、LDH、MDA、Bax表达显著降低(P<0.05);cAMP/PKA/CREB信号通路抑制剂H-89可减弱Eto对神经细胞的保护作用(P<0.05)。结论Eto可能通过激活cAMP/PKA/CREB信号通路,抑制氧化应激和炎症反应,促进细胞增殖,降低细胞凋亡,减弱OGD/R诱导的HT22细胞损伤。

关键词：依托咪酯 cAMP/PKA/CREB信号通路糖氧剥夺/复氧神经元细胞

Optimizing polymer aggregation and blend morphology for boosting the photovoltaic performance of polymer solar cells via a random terpolymerization strategy

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Journal of Energy Chemistry 2021年第8期30卷 30-37,I0002页

作者： Tao zhang Cunbin An Qianglong Lv Jinzhao Qin Yong Cui zhong Zheng Bowei Xu Shaoqing zhang Jianqi zhang Chang He Jianhui Hou State Key Laboratory of Polymer Physics and Chemistry Beijing National Laboratory for Molecular SciencesCAS Research/Education Center for Excellence in Molecular SciencesInstitute of ChemistryChinese Academy of Sciences100190 BeijingChina University of Chinese Academy of Sciences 100049 BeijingChina CAS Key Laboratory of Nanosystem and Hierarchical Fabrication CAS Center for Excellence in NanoscienceNational Center for Nanoscience and Technology100190 BeijingChina

Compared to regular conjugated polymers,the random conjugated terpolymers are usually not beneficial to achieve highly efficient non-fullerene(NF)-based polymer solar cells(PSCs)due to their disordered chemical *** this work,we report two random terpolymer donors(PBNB80 and PBNB50)by tuning the molar ratio of electron-accepting units of 1,3-di(thiophen-2-yl)naphtho[2,3-c]thiophene-4,9-dione(NTD)and 1,3-bis(4-chlorothiophen-2-yl)-4 H,8 H-benzo[1,2-c:4,5-c’]dithiophene-4,8-dione(ClBDD),at the same time,the parent polymers(PBNB100 and PBNB00)are also compared to *** four polymer donors exhibit similar optical bandgaps and gradually deepen highest occupied molecular orbital ***,aggregation and self-organization properties of the random terpolymer donors are optimized,which result in the better morphology and crystal coherence length after blending with NF acceptor of BO-4 ***,a PBNB80:BO-4 Cl blend forms an optimal nanoscale phase-separation morphology,thereby producing an outstanding power conversion efficiency of 16.0%,which is much higher than those(12.8%and 10.7%)of their parent binary polymer donor-based *** work demonstrates that rational using terpolymerization strategy to prepare random terpolymer is a very important method to achieve highly efficient NF-PSCs.

关键词： Polymer solar cells Random terpolymer Non-fullerene acceptor Naphtho[2,3-c]thiophene-4,9-dione Morphology

HL-2A装置二氧化碳激光相干散射系统的研制

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核聚变与等离子体物理 2024年第2期44卷 125-132页

作者：文若楠姚可刘仪许宇鸿石中兵钟武律核工业西南物理研究院成都610041 西南交通大学聚变科学与技术研究所成都610031

在HL-2A装置上成功研制了一套CO_(2)激光相干散射诊断系统,采用了能提高系统空间分辨的切向布局以及双通道的零差式探测设计。两个通道能够同时测量等离子体芯部(ρ≈0.28)波数在10~45cm^(−1)范围中小尺度的湍流变化,其波数分辨率为±3c... 详细信息

在HL-2A装置上成功研制了一套CO_(2)激光相干散射诊断系统,采用了能提高系统空间分辨的切向布局以及双通道的零差式探测设计。两个通道能够同时测量等离子体芯部(ρ≈0.28)波数在10~45cm^(−1)范围中小尺度的湍流变化,其波数分辨率为±3cm^(−1),时间分辨率为0.5μs,能够为等离子体芯部输运研究提供重要数据。此外,由于本诊断系统采用的是主光束与本振光束同时穿过等离子体的光路设计,它还能够探测到等离子体芯部的大尺度宏观等离子体扰动。诊断信号的分析结果显示该系统可以准确地响应等离子体芯部小尺度湍流的变化,同时也能够为芯部宏观不稳定研究提供诊断数据。

关键词：激光相干散射密度扰动小尺度湍流

Upconversion Luminescence Properties and Mechanism of Er^(3+) Doped Ba_(0.65)Sr_(0.35)TiO_3 Ferroelectric Oxide Nanocrystals

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Journal of Wuhan University of Technology(Materials Science) 2015年第2期30卷 241-244页

作者：汪竞阳 zhang Tianjin QU Shaohua zhong Zhicheng WANG Song School of Physics and Electronic Engineering Hubei University of Arts and Science Hubei Key Laboratory of Low Dimensional Optoelectronic Materials and Devices Hubei University of Arts and Science School of Materials Science and Engineering Hubei University

Ba0.65Sr0.35TiO3（BST） nanocrystals doped with different concentrations of Er^3＋ ion were fabricated using sol-gel method. The structure and morphology of these BST nanocrystals were studied using X-ray diffraction（XRD）, field emission scanning electron microscopy（FESEM） and transmission electron microscopy（TEM）. The X-ray diffraction patterns of all the nanocrystals prepared in the study correspond to polycrystalline perovskite BST structure. The blue and green upconversion luminescence properties of Er^3＋ doped BST nanocrystals were investigated under excitation by a 785-nm laser. The upconversion emission bands centered at 407, 523, and 547 nm can be attributed to ^2H9/2, ^4I15/2, ^2H11/2, ^4I15/2, and ^4S3/2, 4I15/2 transitions of Er^3＋ ion, respectively. The upconversion mechanism was studied in detail, based on the laser power dependence of the upconverted emissions. In addition, we examined the dependence of the intensity of green upconverted luminescence on the doping concentration of Er^3＋ ions, and discussed the mechanism underlying the process.

关键词： Er^3+: BST nanocrystals upconvension luminescence quenching

Transition Metal Catalyzed Direct Oxidative Borylation of C--H Bonds

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Chinese Journal of Chemistry 2018年第10期36卷 950-954页

作者： zhong-Tao Jiang Bi-qin Wang zhang-Jie Shi College of Chemistry and Materials Science Sichuan Normal University Chengdu Sichuan 610068 China Department of Chemistry Fudan University Shanghai 200433 China

Organoboron is well-developed and broadly utilized organometallic reagents in organic synthesis due to its extraordinary performances in transition-metal catalyzed C-C and C-X bonds construction. Catalytic C--H borylation and further transformations catalyzed by transition metal catalysts in the absence of oxidants were well studied in decades. However, as known, transition metal catalyzed oxidative C-H borylations were not reviewed up to date. In this article the oxidative borylation of C（sp2）-H and C（sp3）-H bonds were summarized and their mechanisms were also accounted.

关键词： C-H borylation oxidation organoboron transition metal catalysis

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一年生早熟禾种子萌发适宜温度研究

草原与草坪 2024年第1期44卷 183-192页

作者：田晓岚白小明闫玉邦张才忠朱雅楠郑锋陈辉甘肃农业大学草业学院草业生态系统教育部重点实验室甘肃省草业工程实验室中-美草地畜牧业可持续发展研究中心甘肃兰州730070

【目的】探究一年生早熟禾(Poa annua)种子萌发适宜温度。【方法】试验以甘肃省16个不同地区的野生一年生早熟禾种子为材料,设4、8、12、16、20、24、28和32℃8个恒温处理,研究温度对一年生早熟禾种子萌发的影响。【结果】随着温度的升... 详细信息

【目的】探究一年生早熟禾(Poa annua)种子萌发适宜温度。【方法】试验以甘肃省16个不同地区的野生一年生早熟禾种子为材料,设4、8、12、16、20、24、28和32℃8个恒温处理,研究温度对一年生早熟禾种子萌发的影响。【结果】随着温度的升高,一年生早熟禾种子的发芽率、发芽势、发芽指数、胚根长、苗鲜重、活力指数均呈先增后减趋势,胚芽长呈逐渐增大趋势。结论隶属函数综合评价表明,光照周期为16 h光照/8 h黑暗,相对湿度55%的恒温条件下,野生一年生早熟禾种子适宜萌发温度范围为16~24℃,最适萌发温度为24℃。

关键词：一年生早熟禾种子温度萌发特性

电推进GEO卫星的改进粒子群轨道保持优化设计

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宇航学报 2024年第4期45卷 523-531页

作者：吕跃勇王成李笑月郑重郭延宁哈尔滨工业大学航天学院哈尔滨150001 中国科学院微小卫星创新研究院上海201203 哈尔滨工业大学机电工程学院哈尔滨150001

针对地球同步轨道(GEO)卫星轨道保持问题,提出了一种基于改进粒子群算法(PSO)的序列电推力轨道保持方法。首先,建立了GEO卫星高精度非线性轨道动力学模型和序列电推力模型。然后,设计了GEO卫星相对轨道保持策略,建立了以燃料消耗为性能... 详细信息

针对地球同步轨道(GEO)卫星轨道保持问题,提出了一种基于改进粒子群算法(PSO)的序列电推力轨道保持方法。首先,建立了GEO卫星高精度非线性轨道动力学模型和序列电推力模型。然后,设计了GEO卫星相对轨道保持策略,建立了以燃料消耗为性能指标的序列电推力轨道保持问题优化模型并进行了离散化。接着,通过引入差分进化算法和维度学习策略对粒子群优化算法进行了适应性改进,同时对推力大小和作用时间进行寻优计算。最后,通过数值仿真对所提出的改进粒子群优化算法进行了对比校验。结果表明,该方法在完成GEO卫星轨道保持任务的同时具备燃料消耗低和收敛速度快等优点。

关键词：卫星轨道保持电推进粒子群优化差分进化维度学习