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Observations and parametric study on the role of plasma density on extremely low-frequency chorus wave generation

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Science China(Technological Sciences) 2022年第11期65卷 2649-2657页

作者： HE Qian liU Si XIAO Fuliang GAO ZhongLei li Tong SHANG XiongJun ZHOU QingHua YANG chang HE YiHua School of Physics and Electronic Sciences Changsha University of Science and TechnologyChangsha 410114China

Extremely low-frequency(ELF)chorus waves with frequencies below 0.1 fcecan cause the scattering losses of relativistic *** studies have suggested that ELF chorus waves are excited by anisotropic electrons with energies up to a few hundred ke ***,we report an interesting event observed using the Van Allen Probes on November 1,2012,where distinct ELF chorus waves occurred exactly corresponding to the enhancement of the plasma *** the correlated data of particles and plasma environments,the continuous calculation of growth rates along the satellite trajectory was *** linear analysis results display a similar pattern to the observation *** further identify the impact of the plasma density on the frequency control of ELF chorus waves,the growth rates were then calculated by only changing the value of the plasma *** calculation results show that the growth rates move to lower frequencies with plasma density enhancement during the *** findings indicate that the increased plasma density has a considerable impact on the wave *** current study can enrich our understanding of the possible role of plasma density on the generation of ELF chorus waves.

关键词： radiation belts plasma density extremely low-frequency chorus waves numerical simulation

基于KShape数据增广与混合神经网络的注水系统故障诊断

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科学技术与工程 2024年第24期24卷 10235-10243页

作者：于继飞姬煜晨常振宁隋先富曹砚锋杨阳彭建霖李昂海洋油气高效开发全国重点实验室北京100028 中海油研究总院有限责任公司北京100028 中海油能源发展股份有限公司工程技术分公司天津300452

为解决海上油田注水系统故障诊断问题,提出基于KShape数据增广与混合神经网络的故障诊断模型。首先采用KShape时间序列聚类算法实现样本数据增广,然后通过融合双向长短时记忆网络(bidirectional long short-term memory network, BiLSTM... 详细信息

为解决海上油田注水系统故障诊断问题,提出基于KShape数据增广与混合神经网络的故障诊断模型。首先采用KShape时间序列聚类算法实现样本数据增广,然后通过融合双向长短时记忆网络(bidirectional long short-term memory network, BiLSTM)和全卷积神经网络(fully convolutional neural network, FCN)构建混合神经网络模型,最后应用贝叶斯优化算法对模型参数进行全局寻优。结果表明:提出的数据增广方法在数字油田大数据的基础上,能够有效扩充注水系统工况样本。提出的混合神经网络模型较BiLSTM和FCN单一模型效果更好,该模型综合了BiLSTM网络对时间序列数据依赖关系的良好捕捉能力以及FCN网络对局部特征的有效提取能力,较两者在准确率上分别提升4.9%和1.8%。贝叶斯优化方法在寻找更优超参数组合方面有显著效果,为提高模型的鲁棒性和泛化性能起到了重要作用。该方法较传统调参方法在准确率上提升5%,较网格搜索和随机搜索方法分别提升3.7%和1.9%。同时,该方法产生的不同超参数组合下的模型准确率中位数为84.5%,模型准确率在90%以上的占比达到18%。所提出的故障诊断模型,可有效识别地层堵塞、配水器堵塞和油管漏失等故障,为海上油田注水系统故障诊断提供了新的解决方案和有效的技术支持。

关键词： KShape 数据增广混合神经网络贝叶斯优化故障诊断注水系统

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海上风电安全智慧化监测系统设计与实现

水电与新能源 2024年第5期38卷 1-4页

作者：高兴国常增亮李乐乐杨富春李光泽山东电力工程咨询有限公司山东济南250013 山东科技大学测绘与空间信息学院山东青岛266590

海上风电作为清洁能源的重要组成部分,在风力发电中的作用愈加重要。针对人工监测困难、风电运维成本高等因素,采用B/S架构,结合大数据分布式存储技术,设计并实现了海上风电安全智慧化监测系统,旨在解决海上升压站和海上风机结构安全数... 详细信息

海上风电作为清洁能源的重要组成部分,在风力发电中的作用愈加重要。针对人工监测困难、风电运维成本高等因素,采用B/S架构,结合大数据分布式存储技术,设计并实现了海上风电安全智慧化监测系统,旨在解决海上升压站和海上风机结构安全数据的全程自动化采集、数据分析以及运行维护等问题,提高监测效率和运维安全性,为后续海上风电监测和运维提供了技术支持。

关键词：海上风电数据监测智慧化系统实现风电安全

基于风险管控的历史遗留硫磺冶炼废渣综合治理效果

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有色金属（冶炼部分） 2024年第4期 153-161页

作者：施灿海刘明生常普李连强尚大奎傅灿蓝蓉昆明有色冶金设计研究院股份公司昆明650231 昭通市生态环境局镇雄分局云南镇雄657200

为解决赤水河源头流域(云南段)历史遗留硫磺冶炼废渣40多年无序堆积导致流域水体持续酸化的污染问题,通过对“自然衰减”“异位修复”“风险管控”等治理途径分析,提出“风险管控+生态修复”模式开展了该区域内酸性废渣和废水的示范工... 详细信息

为解决赤水河源头流域(云南段)历史遗留硫磺冶炼废渣40多年无序堆积导致流域水体持续酸化的污染问题,通过对“自然衰减”“异位修复”“风险管控”等治理途径分析,提出“风险管控+生态修复”模式开展了该区域内酸性废渣和废水的示范工程治理。在查明治理区域污染因子的基础上,采取“废渣防流失、复合阻隔控制、适生植物配比、污水收集处理和运行监测管理”的集成风险管控技术,分析工程实施前、实施中和实施后的固废属性,以及地表水、地下水和废渣渗滤液中污染因子的变化。结果表明:在投加0.35%~0.65%比例生石灰条件下,固废属性从第Ⅱ类一般工业固废改性为第Ⅰ类一般工业固废;工程完工时,地下水pH即可达标,硫酸盐超标倍数从最大5.3倍削减至1.2倍;工程实施3个月后,渗滤液pH稳定达标,硫酸盐超标倍数从最大3.2倍削减至1.7倍;工程实施7个月后地表水pH达标。基于风险管控的历史遗留硫磺冶炼废渣综合治理,能够满足管控目标,并初步完成了技术推广和应用。

关键词：风险管控历史遗留冶炼废渣集成技术治理效果

Lung protective effects of dietary malate esters derivatives from Bletilla striata against SiO_(2) nanoparticles through activation of Nrf2 pathway

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Chinese Herbal Medicines 2023年第1期15卷 76-85页

作者： Di Zhou Wenhui chang Jiaxin Qi Gang Chen Ning li Key Laboratory of Computational Chemistry-Based Natural Antitumor Drug School of Traditional Chinese Materia MedicaShenyang Pharmaceutical UniversityShenyang 110016China

Objective: To study the protective activities of the dietary malate esters derivatives of Bletilla striata against SiO_(2)nanoparticles-induced A549 cell lines and its mechanism ***: The components were isolated and elucidated by spectroscopic methods such as 1D NMR and 2D NMR. And MTT assays was used to tested these components on the A549 cell survival rates and ROS or proteins levels were detected by Western ***: A new glucosyloxybenzyl 2-isobutylmalate(a malate ester derivative), along with 31 known compounds were isolated and identified from n-BuOH extract of EtOH extract of B. striata. Among them,compounds 3, 4, 11, 12 and 13 possessed noteworthy proliferative effects for damaged cells, with ED50of 14.0, 13.1, 3.7, 11.6 and 11.5 μmol/L, respectively, compared to positive control resveratrol(ED50, 14.7 μmol/L). Militarine(8) prominently inhibited the intracellular ROS level, and increased the expression of Nrf2 and its downstream genes(HO-1 and γ-GCSc). Furthermore, Nrf2 activation mediates the interventional effects of compound 8 against SiO_(2)nanoparticles(nm SiO_(2))-induced lung ***, treatment with compound 8 significantly reduced lung inflammation and oxidative stress in nm SiO_(2)-instilled mice. Molecular docking experiment suggested that 8 bound stably to the HO-1 protein by hydrogen bond ***: The dietary malate esters derivatives of B. striata could significantly increase the viability of nm SiO_(2)-induced A549 cells and decrease the finer particles-induced cell damages. Militarine is especially promising compound for chemoprevention of lung cancer induced by nm SiO_(2)through activation of Nrf2 pathway.

关键词： Bletilla striata(Thunb.)Reichb.f. dietary malate esters derivatives lung cancer chemoprevention militarine SiO_(2)nanoparticles-induced A549 cell

DEK43 is a P-type pentatricopeptide repeat(PPR)protein responsible for the Cis-splicing of nad4 in maize mitochondria

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Journal of Integrative Plant Biology 2020年第3期62卷 299-313页

作者： Ru chang Ren li li Wang lin Zhang Ya Jie Zhao Jia Wen Wu Yi Ming Wei Xian Sheng Zhang Xiang Yu Zhao State Key Laboratory of Crop Biology College of Life SciencesShandong Agricultural UniversityTaian 271018China

Mitochondria, the main energy transducers in plant cells, require the proper assembly of respiratory chain complexes Ⅰ–Ⅴ for their function. The NADH dehydrogenase4(nad4) gene encodes mitochondrial respiratory chain complex Ⅰ subunit Ⅳ, but the mechanism underlying nad4 transcript splicing is unclear. Here, we report that the P-type pentatricopeptide repeat(PPR) protein DEFECTIVE KERNEL 43(DEK43) is responsible for cis-splicing of the nad4 transcript in maize. We demonstrate that DEK43 localizes to both the nucleus and mitochondria. The mutation of Dek43 resulted in embryo-lethal and light-colored defective kernels. Among the 22 mitochondrial group Ⅱ introns, the splicing efficiency of nad4 introns 1 and 3 was reduced by up to 50% compared to the wild type. The levels of complex Ⅰ and supercomplex Ⅰ+Ⅲ2 were also reduced in dek43. Furthermore, in-gel NADH dehydrogenase assays indicated that the activities of these complexes were significantly reduced in dek43. Further, the mitochondrial ultrastructure was altered in the mutant. Together, our findings indicate that DEK43, a dual-localized PPR protein,plays an important role in maintaining mitochondrial function and maize kernel development.

关键词： nad4 function. Together

Discovery of bacteriopheophytin-a in lacustrine deposits from Lake Zigetang on the central Tibetan Plateau and its paleoenvironmental significance

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Science China Earth Sciences 2017年第12期60卷 2171-2180页

作者： li HuaYong ZHANG HuCai chang FengQin ZHENG Qian ZHANG WenXiang LEI Guoliang LEI YanBin PU Yang JI JunFeng Key Laboratory of Plateau Lake Ecology and Global change Yunnan Provincial Key Laboratory of Plateau Geography Process and Environment ChangesCollege of Tourism and Geography ScienceYunnan Normal UniversityKunming 650500China School of Resource Environment and Tourism Anyang Normal UniversityAnyang 455000China College of Urban and Environment Sciences Central China Normal UniversityWuhan 430079China Key Laboratory for Subtropical Mountain Ecology(Ministry of Science and Technology and Fujian Province Funded) Fujian Normal UniversityFuzhoa 350007China Laboratory of Tibetan Environment changes and Land Surface Processes Institute of Tibetan Plateau ResearchChinese Academy of SciencesBeijing 100085China School of Remote Sensing Nanjing University of Information Science&TechnologyNanjing 210044China Institute of Surface Geochemistry Department of Earth SciencesNanjing UniversityNanjing 210093China

Lake Zigetang is located on the central Tibetan Plateau(TP) and represents a rare but typical meromictic lake in *** lake's stable meromixis sustains microflora communities, and changes in these communities are relatively independent of climate. Therefore, these communities can be used as paleoclimate proxies. In this paper, the stratification properties and their relationships with the microflora of Lake Zigetang were analyzed. We found that water depth and climate conditions were two important factors for maintaining meromixis in Lake Zigetang. Generally, stratification was enhanced during warm periods, while temperature differences between the mixolimnion and monimolimnion were decreased during cold periods. The presence of anoxygenic phototrophic bacteria(APB) was demonstrated by the discovery of bacteriopheophytin-a(Bph-a) in the *** bacterial community is mainly concentrated at the bottom of the chemocline and the top of the monimolimnion, where it forms a thin APB layer. Moreover, total APB productivity is mainly affected by the light intensity penetrating to the APB layer,which exponentially increases as the thermocline becomes shallow. Therefore, high Bph-a values in the lake corresponded to a shallow thermocline and warm periods, low Bph-a values corresponded to cold periods, and zero changes indicated that the water was completely mixed and reflected an extreme cold climate or low lake level period. Thus, Bph-a can be used as a climate proxy to reconstruct the history of lake stratification and climate changes.

关键词： Lake Zigetang Tibetan Plateau Meromictic lakes Thermocline Anoxygenic phototrophic bacteria

Copper-catalyzed asymmetric 1,3-dipolar cycloaddition of azomethine ylides withβ-trifluoromethyl-substituted alkenyl heteroarenes

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Science China Chemistry 2023年第11期66卷 3193-3204页

作者： Xiang Cheng Xin chang Yuhong Yang Zongpeng Zhang Jing li Yipu li Wenxiao Zhao Lung Wa Chung Huailong Teng Xiu-Qin Dong Chun-Jiang Wang College of Chemistry and Molecular Sciences Wuhan UniversityWuhan 430072China State Key Laboratory of Organometallic Chemistry Shanghai Institute of Organic ChemistryShanghai 230021China Shenzhen Grubbs Institute Department of Chemistry and Guangdong Provincial Key Laboratory of CatalysisSouthern University of Science and TechnologyShenzhen 518055China College of Science Huazhong Agricultural UniversityWuhan 430070China

Copper-catalyzed asymmetric 1,3-dipolar cycloaddition of azomethine ylides andβ-trifluoromethyl-substituted alkenyl heteroarenes was developed for the first time.A wide range of enantioenriched pyrrolidines containing both heteroarenes and trifluoromethyl group with multiple stereogenic centers could be readily accessible by this method with good to high yields and excellent levels of both stereo-and regioselectivity(up to 99%yield,>20:1 rr,>20:1 dr,and up to 95%ee).Notably,substratecontrolled umpolung-type dipolar cycloaddition was also disclosed in this protocol to achieve regiodivergent synthesis withα-aryl substituted aldimine esters as the dipole *** DFT studies were conducted to explore the origin of the stereo-and regioselectivity of this 1,3-dipolar cycloaddition,and suggest that copper(Ⅱ)salt utilized in this catalytic system could be reduced in-situ to the active copper(Ⅰ)species and might be responsible for the observed high stereo-and regioselectivity.

关键词： asymmetric catalysis 1 3-dipolar cycloaddition chiral pyrrolidines heteroarene trifluoromethyl group

Wavelet analysis of the convectively-coupled equatorial waves

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Science China Earth Sciences 2012年第4期55卷 675-684页

作者： CAO Jie WEN ZhiPing chang youli li XiangRui Department of Atmospheric Science Yunnan UniversityKunming 650091China Monsoon and Environmental Center/Department of Atmospheric Science Sun Yat-Sen UniversityGuangzhou 510275China

The spatial and temporal distribution characteristics of the main convectively-coupled equatorial waves were analyzed with the OLR data provided by NOAA and the method of wavelet *** results indicate that the wavelet analysis can effectively distinguish MJO,Kelvin,ER,TD,and EMRG wave and the characteristics of their activities in *** propagation speeds of MJO and ER wave are the slowest,following by Kelvin and TD wave and with MRG the *** MJO from the Indian Ocean to the West Pacific Ocean,the Kelvin wave near the International Date line,the ER and the TD wave around the West Pacific Ocean and the MRG in the eastern of the International Date line have the biggest wave *** MJO in boreal winter and spring,the Kelvin wave in boreal spring and summer,the ER wave in boreal autumn,and the TD wave in boreal summer are *** WMRG wave activates in boreal autumn,whereas EMRG wave appears *** spatial and temporal characteristics agree well with the results of relevant theoretical studies,indicating that the wavelet analysis in the time-frequency domain is another effective method to reveal the evolution of convectively-coupled equatorial waves.

关键词： equatorial atmosphere convectively-coupled wave wavelet analysis complex least square method