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云南省铅冶炼重金属类危险废物产排污系数研究

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环境科学与技术 2018年第1期41卷 199-204页

作者：黄凯孙科源赵杨邢杰安俊菁云南省固体废物管理中心云南昆明650032

针对云南省的铅冶炼行业企业的原料、工艺、企业规模和固体废物的产生及处置情况进行全面调研,选取具有代表性的企业,研究了工艺及产排污情况。重点分析铅冶炼企业重金属类危险废物产生及变化规律,借助物料衡算、实测法核算和经验估值... 详细信息

针对云南省的铅冶炼行业企业的原料、工艺、企业规模和固体废物的产生及处置情况进行全面调研,选取具有代表性的企业,研究了工艺及产排污情况。重点分析铅冶炼企业重金属类危险废物产生及变化规律,借助物料衡算、实测法核算和经验估值等方法分析,计算出铅冶炼行业生产过程中重金属类危险废物的产生规律和排放等参数。该研究获取危险废物产排污系数可用于排污申报登记、排污收费、核定许可排污量、环境影响评价、标准制定、清洁生产审计等工作,为云南省危险废物环境管理提供理论参考。

关键词：产排污系数重金属危险废物铅冶炼行业

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基于双星编队的高精度光载波相位测量技术

激光与光电子学进展 2023年第7期60卷 165-172页

作者：杨克元姚鑫李嘉敏王国永张中英中国航天科技集团有限公司第五研究院西安分院空间通信与导航技术研究所陕西西安710100

基于双星编队的激光干涉测距载荷能够在轨验证基于三星编队的空间引力波探测任务的多项关键技术。在空间引力波探测任务中,为实现皮米级的星间位移测量精度,要求在mHz频段实现优于10−6 cycle/Hz1/2的光载波相位测量精度。限制测相精度... 详细信息

基于双星编队的激光干涉测距载荷能够在轨验证基于三星编队的空间引力波探测任务的多项关键技术。在空间引力波探测任务中,为实现皮米级的星间位移测量精度,要求在mHz频段实现优于10−6 cycle/Hz1/2的光载波相位测量精度。限制测相精度的瓶颈因素在于相位计中模数转换器的采样抖动。利用导频和时钟边带调制技术可在数据后处理中抑制采样抖动噪声。将面向三星编队时间延迟干涉组合的时钟边带调制技术推广到更普遍的基于双星编队的双向光载波相位测量系统中,并考虑到星间多普勒频移,给出了抑制光载波相位测量过程中采样抖动噪声的系统性方案。该方案能够应用在下一代地球重力场探测任务中,以在轨验证面向空间引力波探测的相位计技术,同时有望应用于高精度星间激光时频传递项目,支撑未来全球卫星导航系统。

关键词：测量相位测量干涉度量法光载波拍频边带调制

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浅谈高山转播发射台地面数字发射机的管理和维护措施

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中国有线电视 2022年第6期 62-64页

作者：黄明裕文明强杨科元玉屏侗族自治县广播电视无线发射台贵州玉屏554000

伴随广播电视事业的快速发展,地面数字电视发射机在各级高山广播电视转播发射台中得到了广泛的应用。通过对管护经验的回顾,以某KT-UDT51X地面数字发射机为例,探讨高山转播发射台地面数字发射机的日常管理与维护方法,以及常见故障处理... 详细信息

伴随广播电视事业的快速发展,地面数字电视发射机在各级高山广播电视转播发射台中得到了广泛的应用。通过对管护经验的回顾,以某KT-UDT51X地面数字发射机为例,探讨高山转播发射台地面数字发射机的日常管理与维护方法,以及常见故障处理办法。

关键词：高山转播发射台地面数字发射机管理与维护

一种基于星载GNSS接收机的高轨卫星自主导航滤波算法

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空间电子技术 2020年第3期17卷 43-50页

作者：张蓬杨克元王延光蒙艳松中国空间技术研究院西安分院西安710000

星载GNSS接收机在低轨卫星自主导航和精密定轨等应用领域已经显示了高精度、高自主性、不依赖地面支持等技术优势。对于高轨卫星应用,星载GNSS接收机面临一些新的挑战。由于需要接收来自地球另外一侧的GNSS旁瓣信号,使得用户等效测距误... 详细信息

星载GNSS接收机在低轨卫星自主导航和精密定轨等应用领域已经显示了高精度、高自主性、不依赖地面支持等技术优势。对于高轨卫星应用,星载GNSS接收机面临一些新的挑战。由于需要接收来自地球另外一侧的GNSS旁瓣信号,使得用户等效测距误差和几何分布因子恶化,引起标准定位性能下降。特别的,对于只能使用GNSS广播星历的实时自主导航应用,GNSS广播星历引入了非白噪声特性的用户测距误差。其难以被经典的EKF滤波方法平滑,限制了自主导航定位精度。文章研究一种基于星载GNSS接收机的高轨卫星自主导航滤波算法,该算法使用增强扩展卡尔曼滤波器(Augmented EKF)融合轨道动力学模型与GNSS观测数据,并对GNSS广播星历引入的系统性误差进行动态估计以削弱其对最终导航定位的影响。最后,通过仿真平台进行了算法验证。仿真结果显示,使用单GPS可在GEO轨道达到优于10米(3D RMS)的导航定位精度。文章提出的方法达到与国际先进产品同等精度,可用于高轨卫星高精度自主导航。

关键词：星载GNSS接收机高轨卫星导航滤波 AEKF

Deformation mechanism of rock mass and prestressed anchor cable support technology of Haidong soft rock tunnel

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Journal of Mountain Science 2024年第12期21卷 4299-4322页

作者： LEI Xiaotian TAO Zhigang LIU keyuan yang Hong CAI Mingjiu FAN Xiaowei State Key Laboratory for Tunnel Engineering Beijing 100083China School of Mechanics and Civil Engineering China University of Mining&TechnologyBeijing 100083China China Railway 20th Bureau Group Co. Ltd.Xi’an 710016China China Railway 5th Bureau Fifth Company Chenzhou 423000China School of Energy and Environment Zhongyuan University of TechnologyZhengzhou 450007China

The Haidong Tunnel is one of the four soft rock tunnels of the Central Yunnan Water Diversion Project(CYWDP),where large deformation hazards of soft rock occur frequently,which seriously affect construction *** effect of highly prestressed anchor cable support was studied based on the active support test in the No.3 branch tunnel of Haidong ***,the geological conditions and failure causes were analyzed on the basis of the results of geological survey,in-situ test,and rock laboratory ***,the Mohr circle form of the highly prestressed anchor cable active support theory for the support of bedded rock mass was given in combination with the excavation compensation *** is considered that the prestress active compensation value required for the bedded rock mass is larger than that for the homogeneous rock *** deformations of rock mass under both passive and active supports were analyzed by numerical ***,the'pressure bubble'mechanical model for anchor cable support of bedded rock mass in Haidong Tunnel is *** monitoring results show that the highly prestressed anchor cable support can control rock mass deformation well,with a maximum deformation of about 200 *** prestressed anchor cable is effective in the bedded stratum,which makes the stress of rock mass uniform and reduces the risk of failure of steel arches due to local ***,the expansion of plastic zone was efficiently controlled,which is of positive significance for the overall stability of rock mass.

关键词： Central Yunnan Water Diversion Project Large deformation of soft rock Prestressed anchor cable Active support 'Pressure bubble'mechanical model

Time-Varying Mesh Stiffness Calculation and Dynamic Modeling of Spiral Bevel Gear with Spalling Defects

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Journal of Dynamics, Monitoring and Diagnostics 2024年第2期3卷 143-155页

作者： keyuan Li Baijie Qiao Heng Fang Xiuyue yang Xuefeng Chen School of Mechanical Engineering Xi’an Jiaotong UniversityXi’anPR China National Key Lab of Aerospace Power System and Plasma Technology Xi’an Jiaotong UniversityXi’anPR China

Time-varying mesh stiffness(TVMS)is a vital internal excitation source for the spiral bevel gear(SBG)transmission *** defect often causes decrease in gear mesh stiffness and changes the dynamic characteristics of the gear system,which further increases noise and *** paper aims to calculate the TVMS and establish dynamic model of SBG with spalling *** this study,a novel analytical model based on slice method is proposed to calculate the TVMS of SBG considering spalling ***,the influence of spalling defect on the TVMS is studied through a numerical simulation,and the proposed analytical model is verified by a finite element ***,an 8-degrees-of-freedom dynamic model is established for SBG transmission *** the spalling defect into TVMS,the dynamic responses of spalled SBG are *** numerical results indicate that spalling defect would cause periodic impact in time ***,an experiment is designed to verify the proposed dynamic *** experimental results show that the spalling defect makes the response characterized by periodic impact with the rotating frequency of spalled pinion.

关键词： dynamic modeling slice method spalling spiral bevel gear time-varying mesh stiffness(TVMS)

Identification and Characterization of a Distinct Strain of Beak and Feather Disease Virus in Southeast China

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Virologica Sinica 2020年第1期35卷 43-51页

作者： Yanmei Ma Xiaoyong Chen keyuan Chen Xiancheng Zeng Shili yang Wei Chang Yao Tang Xiaoli Chen Song Wang Ji-Long Chen Fujian Agriculture and Forestry University Fuzhou 350002China CAS Key Laboratory of Pathogenic Microbiology and Immunology Institute of MicrobiologyChinese Academy of Sciences(CAS)Beijing 100101China Fuzhou Zoo Fuzhou 350012China

Beak and feather disease virus(BFDV) is an infectious agent responsible for feather degeneration and beak deformation in birds. In March 2017, an epidemic of psittacine beak and feather disease(PBFD) struck a farm in Fuzhou in the Fujian Province of southeast China, resulting in the death of 51 parrots. In this study, the disease was diagnosed and the pathogen was identified by PCR and whole genome sequencing. A distinct BFDV strain was identified and named as the FZ *** BFDV strain caused severe disease symptoms and pathological changes characteristic of typical PBFD in parrots, for example, loss of feathers and deformities of the beak and claws, and severe pathological changes in multiple organs of the infected birds. Phylogenetic analysis showed that the FZ strain was more closely related to the strain circulating in New Caledonia than the strains previously reported in China. Nucleotide homology between the FZ strain and other 43 strains of BFDV ranged from 80.0% to 92.0%. Blind passage experiment showed that this strain had limited replication capability in SPF Chicken Embryos and DF-1 Cells. Furthermore, the capsid(Cap) gene of this FZ strain was cloned into the p GEX-4 T-1 expression vector to prepare the polyclonal anti-Cap antibody. Western blotting analysis using the anti-Cap antibody further confirmed that the diseased parrots were infected with BFDV. In this study, a PBFD and its pathogen was identified for the first time in Fujian Province of China, suggesting that future surveillance of BFDV should be performed.

关键词： Beak and feather disease virus(BFDV) Parrot FZ strain Capsid protein(Cap) Phylogenetic analysis

Aloe emodin promotes mucosal healing by modifying the differentiation fate of enteroendocrine cells via regulating cellular free fatty acid sensitivity

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Acta Pharmaceutica Sinica B 2024年第9期14卷 3964-3982页

作者： Weilian Bao Jiaren Lyu Guize Feng Linfeng Guo Dian Zhao keyuan You yang Liu Haidong Li Peng Du Daofeng Chen Xiaoyan Shen Department of Pharmacology&the Key Laboratory of Smart Drug Delivery Ministry of Education School of PharmacyFudan UniversityShanghai 201210China Department of Natural Medicine School of PharmacyFudan UniversityShanghai 201210China Department of Colorectal and Anal Surgery Xinhua HospitalShanghai Jiao Tong University School of MedicineShanghai 200092China Shanghai Colorectal Cancer Research Center Shanghai 200092China

The proper differentiation and reorganization of the intestinal epithelial cell population is critical to mucosal regeneration post *** retaining cells(LRCs)expressing SRY-box transcription factor 9(SOX9)promote epithelial repair by replenishing LGR5 t intestinal stem cells(ISCs).While,LRCs are also considered precursor cells for enteroendocrine cells(EECs)which exacerbate mucosal damage in inflammatory bowel disease(IBD).The factors that determine LRC-EEC differentiation and the effect of intervening in LRC-EEC differentiation on IBD remain *** this study,we investigated the effects of a natural anthraquinone called aloe emodin(derived from the Chinese herb rhubarb)on mucosal healing in IBD *** findings demonstrated that aloe emodin effectively interfered with the differentiation to EECs and preserved a higher number of SOX9t LRCs,thereby promoting mucosal ***,we discovered that aloe emodin acted as an antagonist of free fatty acid receptors(FFAR1),suppressing the FFAR1-mediated Gbg/serine/threonine-protein kinase(AKT)pathway and promoting the translocation of forkhead box protein O1(FOXO1)into the nucleus,ultimately resulting in the intervention of differentiation *** findings reveal the effect of free fatty acid accessibility on EEC differentiation and introduce a strategy for promoting mucosal healing in IBD by regulating the FFAR1/AKT/FOXO1 signaling pathway.

关键词： LRCs ISCs EECs IBD SOX9 Aloe emodin FFAR1 FOXO1

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扶贫开发与农村低保衔接研究:一个文献述评

中国农业大学学报（社会科学版） 2016年第5期33卷 81-88页

作者：焦克源杨乐兰州大学管理学院

在全面建成小康社会的决胜阶段,扶贫开发政策和农村低保制度实现有效衔接(简称"两项制度衔接")是推进精准扶贫的必然要求,是实现全面建成小康社会的基础性条件。通过对两项制度衔接相关文献的梳理,研究发现学界主要从顶层理念和衔接实... 详细信息

在全面建成小康社会的决胜阶段,扶贫开发政策和农村低保制度实现有效衔接(简称"两项制度衔接")是推进精准扶贫的必然要求,是实现全面建成小康社会的基础性条件。通过对两项制度衔接相关文献的梳理,研究发现学界主要从顶层理念和衔接实践两个逻辑层次进行了较为全面的探究,但在研究深度与广度上都有待拓展,即在研究方法上应尝试运用定量研究方法,研究区域上应着重考察集中连片特困区,研究方向上应侧重于对衔接效果的评估体系及其应用研究等。最后,研究认为两项制度衔接实践是社会保障与扶贫开发联动扶贫的"先行军",社会保障与扶贫开发联动扶贫是我国精准扶贫战略实施的主要路径选择。

关键词：扶贫开发农村低保衔接精准扶贫