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Large-aperture Telescope Tracking Control Based on Time-synchronization Strategy

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Research in Astronomy and Astrophysics 2024年第3期24卷 34-46页

作者： Yun Li Yu Ye shi-hai yang Ling-Zhe Xu Jin Xu hai Wang Zhuang-Zhuang Deng Rui-Qiang Liu Xiao-Jie Gu Bo-Zhong Gu Nanjing Institute of Astronomical Optics&Technology Chinese Academy of SciencesNanjing 210042China CAS Key Laboratory of Astronomical Optics&Technology Nanjing Institute of Astronomical Optics&TechnologyNanjing 210042China University of Chinese Academy of Sciences Beijing 100049China

A time-synchronization strategy for packetized transmission of target position about a large-aperture telescope observation control system has been proposed in this *** with the existing telescope tracking strategy,the target position packing and sending strategy based on the time synchronization method proposed in this paper has the advantages of high stability and ***,the telescope tracking observation control method was elaborated in this paper,including the motion pattern during telescope ***,the strategy for packetizes transmission of target positions based on time-synchronization is established and lists the detailed ***,the performance of the tracking strategy is verified using the 2.5 m telescope for the simulated uniform speed star and the blind-tracking fixed star HIP 31216,*** test results show that the accuracy root mean square of the tracking strategy proposed in this paper is less than 0".02 at 30 minutes,and the performance is much better than the design requirement of 0".*** most important advantage of this tracking strategy is that the telescope can guarantee normal tracking for a certain period of time even if the hardware or software of the host computer is abnormal.

关键词： miscellaneous-telescopes-methods observational-methods analytical

原水生物膜预处理工艺对有机碳源的响应特征--以脱氮性能与菌群结构为例

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中国环境科学 2024年第7期44卷 3800-3809页

作者：叶丽慧刘欣灵林思慧石海洋赵一淳陈东之阳广凤浙江海洋大学石油化工与环境学院浙江舟山316022 浙江省石油化工环境污染控制重点实验室浙江舟山316022

原水生物膜预处理系统运行性能受限于原水水质特征,试验以模拟污染原水为处理对象,以彗星式纤维填料和活性炭填料为生物膜载体构建了实验室规模的原水生物膜预处理系统,采用批次试验探究系统运行性能与菌群结构对不同有机碳源乙酸钠和... 详细信息

原水生物膜预处理系统运行性能受限于原水水质特征,试验以模拟污染原水为处理对象,以彗星式纤维填料和活性炭填料为生物膜载体构建了实验室规模的原水生物膜预处理系统,采用批次试验探究系统运行性能与菌群结构对不同有机碳源乙酸钠和腐殖酸的响应特征.试验结果表明,原水生物膜预处理系统能长时间稳定运行,系统平均氨氮去除率(ARE)为90.1%.乙酸钠对两种填料生物膜的氨氮去除性能几乎无影响.以腐植酸为有机碳源具有更强的硝化能力,取得最高ARE值90.5%±5.6%.乙酸钠能够促进彗星式纤维填料生物膜胞外聚合物(EPS)的形成,腐殖酸会降低EPS中PN含量.以活性炭为载体明显增加了EPS的PN/PS值,且具有较高的菌群多样性,更有利于生物膜的形成.生物膜样品中,占据前三位的门是Proteobacteria､Planctomycetes和Acidobacteria.彗星式纤维填料生物膜,乙酸钠和腐植酸分别强化了优势门Proteobacteria(53.9%)细菌和优势属Nitrospira(10.7%)的累积.以彗星式纤维填料与活性炭为载体生物膜样品优势属分别为Nitrospira和Aridibacter.腐殖酸更有利于Nitrospira和Bdellovibrio的富集,乙酸钠更有利于Aridibacter的富集.

关键词：原水生物膜有机碳源运行性能菌群结构胞外聚合物

Hydrogen storage thermodynamics and kinetics of as-cast Ce-Mg-Ni-based alloy

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Journal of Iron and Steel Research(International) 2024年第3期31卷 752-766页

作者： Yan Qi Xin Zhang Jun Li Dong-liang Zhao shi-hai Guo yang-huan Zhang Department of Functional Material Research Central Iron and Steel Research InstituteBeijing 100081China China Rare Earth New Material(Weishan)Co..Ltd. Jining 277600ShandongChina Collaborative Innovation Center of Integrated Exploitation of Bayan Obo Multi-Metal Resources Inner Mongolia University of Science and TechnologyBaotou 014010Inner MongoliaChina

The reaction kinetics of alloys based on magnesium are known to be greatly improved by the partial substitution of Mg with rare earths and transition metals,particularly *** enhanced superficial hydrogen dissociation rate,the weakened Mg-H bond and the lower activation energy following element replacement are thought to be related to the better *** experimental alloys Ce5Mg_(95-x)Ni_(x)(x=5,10,15)were smelted by the vacuum induction *** phase transformation and structural evolution of experimental alloys before and after reaction with hydrogen were char-acterized by X-ray diffraction,scanning electron microscopy and transmission electron *** cast specimens contain CeMg_(12),Mg and Mg_(2)Ni phases,and the increase in Ni content results in an obvious growth of Mg_(2)Ni *** isothermal and non-isothermal hydrogenation and dehydrogenation kinetics of the experimental specimens were investi-gated using the Sievert apparatus,differential scanning calorimetry and thermal gravimetric *** activation energy may be calculated using the Arrhenius and Kissinger *** experimental alloys have been shown to have good activation properties,with a reversible hydriding and dehydriding capacities of around 5.0 wt.%in the first *** initial dehydrogenation temperature of MgH_(2) decreases from 557.5 to 537.7 K with changing Ni content from 5 to 15 at.%.The dehydrogenation activation energy also reduces from 77.09 to 62.96 kJ/mol,which explains the improved hydrogen storage performance caused by Ni *** can be shown that the impact of Ni on the decomposition enthalpy of MgH_(2) is quite modest,with the absolute enthalpy(ΔHr)only decreasing from 78.48 to 76.15 kJ/mol.

关键词： Mg-based alloy Ni content Hydrogen storage kinetics Thermodynamic property Activation energy

How variable progenitor clones construct a largely invariant neocortex

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National Science Review 2024年第1期11卷 129-144页

作者： Zhongfu Shen Jiajun yang Qiangqiang Zhang Kuiyu Wang Xiaohui Lv Xiaolin Hu Jian Ma Song-hai shi New Cornerstone Science Laboratory IDG/McG overn Institute for Brain Research Tsinghua-Peking Center for Life Sciences Beijing Frontier Research Center for Biological Structure School of Life Sciences Tsinghua University Department of Computer Sciences Tsinghua University College of Life Sciences Nankai University Chinese Institute for Brain Research

The neocortex contains a vast collection of diverse neurons organized into distinct layers. While nearly all neocortical neurons are generated by radial glial progenitors(RGPs), it remains largely unclear how a complex yet organized neocortex is constructed reliably and robustly. Here, we show that the division behavior and neuronal output of RGPs are highly constrained with patterned variabilities to support the reliable and robust construction of the mouse neocortex. The neurogenic process of RGPs can be well-approximated by a consistent Poisson-like process unfolding over time, producing deep to superficial layer neurons progressively. The exact neuronal outputs regarding layer occupation are variable; yet, this variability is constrained systematically to support all layer formation, largely reflecting the variable intermediate progenitor generation and RGP neurogenic entry and exit timing differences. Together, these results define the fundamental features of neocortical neurogenesis with a balanced reliability and variability for the construction of the complex neocortex.

关键词： neocortex radial glial progenitor intermediate progenitor neurogenesis clonal variability layer formation

Learning topological defects formation with neural networks in a quantum phase transition

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Communications in Theoretical Physics 2024年第5期76卷 68-76页

作者： Han-Qing shi hai-Qing Zhang Center for Gravitational Physics Department of Space ScienceBeihang UniversityBeijing 100191China Peng Huanwu Collaborative Center for Research and Education Beihang UniversityBeijing 100191China

Neural networks possess formidable representational power,rendering them invaluable in solving complex quantum many-body *** they excel at analyzing static solutions,nonequilibrium processes,including critical dynamics during a quantum phase transition,pose a greater challenge for neural *** address this,we utilize neural networks and machine learning algorithms to investigate time evolutions,universal statistics,and correlations of topological defects in a one-dimensional transverse-field quantum Ising ***,our analysis involves computing the energy of the system during a quantum phase transition following a linear quench of the transverse magnetic field *** excitation energies satisfy a power-law relation to the quench rate,indicating a proportional relationship between the excitation energy and the kink ***,we establish a universal power-law relationship between the first three cumulants of the kink numbers and the quench rate,indicating a binomial distribution of the ***,the normalized kink-kink correlations are also investigated and it is found that the numerical values are consistent with the analytic formula.

关键词： neural networks machine learning transverse-field quantum Ising model kibble-zurek mechanism

Towards the insights into the deactivation behavior of acetylene hydrogenation catalyst

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Petroleum Science 2024年第2期21卷 1405-1414页

作者： hai-Xia Su yang Jiao Jian-Gong shi Zhi-Wei Yuan Di Zhang Xu-Peng Wang Jing Ren Dan Liu Jian-Zhou Gui hai-yang Gao Xiao-Li Xu State Key Laboratory of Separation Membranes&Membrane Processes Tianjin Key Laboratory of Green Chemical Technology and Process EngineeringSchool of Material Science and EngineeringTiangong UniversityTianjin300387China Institute of Engineering Technology Sinopec Catalyst Co.LtdBeijing101100China State Key Laboratory of Separation Membranes and Membrane Processes Tianjin Key Laboratory of Green Chemical Technology and Process EngineeringSchool of ChemistryTiangong UniversityTianjin300387China

A series of model catalysts were obtained by treating commercial fresh and spent catalysts unloaded from the factory with different methods, including green oil dipping, extraction and high-temperature regeneration;finally, the deactivation behavior of the commercial catalyst for acetylene hydrogenation were studied. The influence of various possible deactivation factors on the catalytic performance was elucidated via detailed structural characterization, surface composition analysis, and activity *** results showed that green oil, carbon deposit and sintering of active metal were the main reasons for deactivation, among which green oil and carbon deposit led to rapid deactivation, while the activity could be recovered after regeneration by high-temperature calcination. The sintering of active metal components was attributed to the high-temperature regeneration in hydrothermal conditions, which was slow but irreversible and accounted for permanent deactivation. Thus, optimizing the regeneration is expected to extend the service life of the commercial catalyst.

关键词： Acetylene Hydrogenation Green oil Carbon deposit Sintering Catalyst deactivation

Yemazhui(Herba Eupatorii Lindleyani)ameliorates lipopolysaccharide-induced acute lung injury via modulation of the toll-like receptor 4/nuclear factor kappa-B/nod-like receptor family pyrin domain-containing 3 protein signaling pathway and intestinal flor

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Journal of Traditional Chinese Medicine 2024年第2期44卷 303-314页

作者： REN Li hai yang yang Xue LUO Xianqin Chongqing Key Laboratory of Traditional Chinese Medicine for Prevention and Cure of Metabolic Diseases College of Traditional Chinese MedicineChongqing Medical UniversityChongqing 400016China College of Basic Medicine Chongqing Medical UniversityChongqing 400016China

OBJECTIVE:To investigate the impact of Yemazhui(Herba Eupatorii Lindleyani,HEL)against lipopolysaccharide(LPS)-induced acute lung injury(ALI)and explore its underlying mechanism in ***:The chemical constituents of HEL were analyzed by ultra-high performance liquid chromatographyquadrupole time-of-flight mass spectrometry ***,HEL was found to suppress LPS-induced ALI in ***-week-old male Sprague-Dawley rats were randomly divided into 6 groups:control,LPS,Dexamethasone(Dex),HEL low dose 6 g/kg(HEL-L),HEL medium dose 18 g/kg(HEL-M)and HEL high dose 54 g/kg(HEL-H)*** model rats were intratracheally injected with 3 mg/kg LPS to establish an ALI *** counts,lung wet/dry weight ratio,as well as myeloperoxidase(MPO)activity were determined followed by the detection with hematoxylin and eosin staining,enzyme linked immunosorbent assay,quantitative real time polymerase chain reaction,western blotting,immunohistochemistry,and ***,to explore the effect of HEL on ALI-mediated intestinal flora,we performed 16s rRNA sequencing analysis of intestinal ***:HEL attenuated LPS-induced inflammation in lung tissue and intestinal flora *** study indicated that HEL suppressed the lung coefficient and wet/dry weight ratio of LPS-induced ALI in rats,inhibited leukocytes exudation and MPO activity,and improved the pathological injury of lung *** addition,HEL reduced the expression of tumor necrosis factoralpha,interleukin-1beta(IL-1β)and interleukin-6(IL-6)in bronchoalveolar lavage fluid and serum,and inhibited nuclear displacement of nuclear factor kappa-B p65(NF-κBp65).And 18 g/kg HEL also reduced the expression levels of toll-like receptor 4(TLR4),myeloid differentiation factor 88,NF-κBp65,phosphorylated inhibitor kappa B alpha(phospho-IκBα),nod-like receptor family pyrin domain-containing 3 protein(NLRP3),IL-1β,and interleukin-18(IL-18)in lung tissue,and regulated intestinal flora disturban

关键词： Yemazhui(Herba Eupatorii Lindleyani) acute lung injury anti-inflammation toll-like receptor 4 nuclear factor kappa-B nod-like receptor family pyrin domain-containing 3 protein signal transduction gastrointestinal microbiome

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CD3ε of a pan T cell marker involved in mouse Aspergillus fumigatus keratitis

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International Journal of Ophthalmology(English edition) 2024年第4期17卷 616-624页

作者： Wen-Hao shi Li-Mei Wang hai-Jing Yan shi-Long Liu Xian yang Xue-Jiaoyang Cheng-Ye Che Department of Ophthalmology the Affiliated Hospital of Qingdao UniversityQingdao 266000Shandong ProvinceChina Weifang Medical University Weifang 261053Shandong ProvinceChina Eye Hospital of Wenzhou Medical University Wenzhou 325027Zhejiang ProvinceChina Department of Medical Engineering the Affiliated Hospital of Qingdao UniversityQingdao 266000Shandong ProvinceChina

AIM:To explore whether CD3ε is involved in the adaptive immunity of Aspergillus fumigatus(***)keratitis in mice and the role of innate and adaptive immunity in ***:Mice models of *** keratitis were established by intra-stromal injection and corneal epithelial *** injections of natamycin,wedelolactone,LOX-1 inhibitor(poly I)or Dectin-1 inhibitor(laminarin)were used to treat mice with *** *** were pretreated by intraperitoneal injection of anti-mouse CD3ε.We observed the corneal infection of mice under the slit lamp microscope and made a clinical *** protein expression of CD3ε and interleukin-10(IL-10)was determined by Western ***:With the disease progresses,the degree of corneal opacity and edema *** the intrastromal injection models,CD3εprotein expression began to increase significantly on the 2^(nd) ***,in the scraping epithelial method models,CD3ε only began to increase on the 3^(rd) *** natamycin treatment,the degree of corneal inflammation in mice was significantly attenuated on the 3^(rd) *** wedelolactone treatment,the severity of keratitis *** the amount of CD3ε protein was also reduced,compared with the control *** inhibiting LOX-1 and Dectin-1,there was no significant difference in CD3ε production compared with the control *** inhibiting CD3ε,corneal ulcer area and clinical score increased,and IL-10 expression was ***:As a pan T cell marker,CD3ε participate in the adaptive immunity of *** keratitis in *** our mice models,the corneas will enter the adaptive immune stage *** regulating IL-10,CD3ε exerts antiinflammatory and repairs effects in the adaptive immune stage.

关键词： CD3ε adaptive immunity Aspergillus fumigatus keratitis interleukin-10

Experimental study on the angle of repose of pulverized coal

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Particuology 2010年第5期8卷 482-485页

作者： Wei Wang Jiansheng Zhang shi yang hai Zhang hairui yang Guangxi Yue Department of Thermal Engineering Tsinghua University Beijing 100084 PR China

An experimental study on the angle of repose （AoR） of pulverized coal with different particle sizes and different moisture contents （MC） was conducted. Three different measurement methods, free-base piling, fixed-base piling and sliding, were used. The data were analyzed by one-way and two-way analysis of variance. The results showed that the AoRs of pulverized coal with particle sizes smaller than 150 μm were in the range of 30-50°. The characterization of the flowability of pulverized coal was some cohesiveness or true cohesiveness. The increase of MC will increase AoR and thus decrease the flowability of the powder. However, the particle size effect is bifurcated. Below a critical size, the decrease of particle size decreases the flowability; while above the critical size, the decrease of particle size increases the flowability. It was found that the value of the critical size strongly depends on the powder density. Moreover, the AoR dependence on particle size could be linked with the Geldart＇s particle classification. The critical size at the turning point is on the boundary between Group A and Group B in Geldart＇s classification diagram. Based on the experimental results, there is no significant cross interaction between particle size and MC. The AoRs measured by free-base method and fixed-base method are close, but both remarkably smaller than that measured by the sliding method.

关键词： Angle of repose (AoR)Pulverized coalParticle sizeMoisture content