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Natural Products and Bioprospecting 2021年第3期11卷 325-332页

作者： yi-jie zhai Jian-Nan Li Yu-Qi Gao Lin-Lin Gao Da-Cheng Wang Wen-Bo Han Jin-Ming Gao Shaanxi Key Laboratory of Natural Products and Chemical Biology College of Chemistry and PharmacyNorthwest A&F UniversityYanglingShaanxi 712100People’s Republic of China

Two new sterpurane sesquiterpenoids named sterpurol D(1)and sterpurol E(2),and one skeletally new sesquiterpene,cryptomaraone(3),bearing a 5,6-fused bicyclic ring system,along with five known ones,sterpurol A(4),sterpurol B(5),paneolilludinic Acid(6),murolane-2α,9β-diol-3-ene(7)and(-)-10,11-dihydroxyfarnesol(8)were isolated from an endolichenic fungus Cryptomarasmius *** structures of the new compounds were elucidated by analysis of NMR spectroscopic spectra and HRESIMS *** absolute configurations of 1 and 2 were established by spectroscopic data analysis and comparison of specific optical rotation,as well as the biosynthetic ***,compounds 1,2,4-6,and 8 showed significant nitric oxide(NO)production inhibition in Lipopolysaccharide(LPS)-induced BV-2 microglial cells with the IC50 values ranging from 9.06 to 14.81μM.

关键词： Endolichenic fungus Cryptomarasmius aucubae Sesquiterpenes Anti-neuroinflammatory activity

Mesospheric tide comparisons at low latitudes observed by two collocated meteor radars

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Earth and Planetary Physics 2025年第1期9卷 54-68页

作者： Jian Li Wen yi XiangHui Xue jie Zeng HaiLun Ye JianYuan Wang JinSong Chen Na Li TingDi Chen Chinese Academy of Sciences(CAS)Key Laboratory of Geospace Environment Department of Geophysics and Planetary SciencesUniversity of Science and Technology of ChinaHefei 230026China CAS Center for Excellence in Comparative Planetology Anhui Mengcheng Geophysics National Observation and Research StationUniversity of Science and Technology of ChinaHefei 230026China Hefei National Laboratory University of Science and Technology of ChinaHefei 230026China Collaborative Innovation Center of Astronautical Science and Technology Harbin 150001China National Key Laboratory of Electromagnetic Environment China Research Institute of Radiowave PropagationQingdao 266107China Yunnan Kunming Electromagnetic Environment National Observation and Research Station Qujing Kunming 655000China

Accurate knowledge of mesospheric winds and waves is essential for studying the dynamics and climate in the mesosphere and lower thermosphere(MLT)*** this study,we conduct a comparative analysis of the mesosphere tidal results obtained from two adjacent meteor radars at low latitudes in Kunming,China,from November 2013 to December *** two radars operate at different frequencies of 37.5 MHz and 53.1 MHz,***,overall good agreement is observed between the two radars in terms of horizontal winds and tide *** results show that the dominant tidal waves of the zonal and meridional winds are diurnal and semidiurnal ***,we conduct an exhaustive statistical analysis to compare the tidal amplitudes and vertical wavelengths recorded by the dual radar systems,which reveals a high degree of alignment in tidal *** investigation includes variances and covariances of tidal amplitudes,which demonstrate remarkable consistency across measurements from both *** finding highlights clear uniformity in the mesospheric tidal patterns observed at low latitudes by the two neighboring meteor *** of the comparative analysis specifically underscore the significant correlation in vertical wavelength measurements,validating the robustness of radar observations for tidal research.

关键词： mesosphere and lower thermosphere region meteor radar mesospheric winds tides

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区域医疗系统抗震韧性综述

哈尔滨工业大学学报 2025年第1期57卷 1-12页

作者：裴顺顺翟长海胡杰结构工程灾变与控制教育部重点实验室(哈尔滨工业大学) 哈尔滨150090 土木工程智能防灾减灾工业和信息化部重点实验室(哈尔滨工业大学) 哈尔滨150090

韧性作为一种新的灾害风险管理理念,已成为防灾减灾领域的研究热点,考虑到医疗系统在城市运行和灾后救援中的重要作用,在地震期间和之后,区域医疗系统应该具有足够的韧性,并提供连续的医疗服务。如何综合考虑区域范围内多家医院和交通... 详细信息

韧性作为一种新的灾害风险管理理念,已成为防灾减灾领域的研究热点,考虑到医疗系统在城市运行和灾后救援中的重要作用,在地震期间和之后,区域医疗系统应该具有足够的韧性,并提供连续的医疗服务。如何综合考虑区域范围内多家医院和交通系统的安全性、应急响应能力、多系统的整合与协作,有效评估区域医疗系统的抗震韧性水平,并提出科学的改进建议,对建设韧性城乡具有重要的理论意义。本文通过梳理国内外文献,阐明了区域医疗系统韧性的概念和内涵,总结了地震后短期应急和长期修复两个阶段韧性评估的重点,归纳了现有区域医疗系统韧性的评估框架,从医院集群系统、面向医疗的交通系统、应急医疗服务系统和医疗-交通耦合系统4个方面阐述了现有评估方法。区域医疗系统韧性的研究旨在提高其面对灾害时的抵抗性、短期适应性和长期恢复性,这些研究对于满足紧急和日常的医疗需求以及指导灾后恢复具有重要意义。目前区域医疗系统抗震韧性的研究取得了一些进展,但仍然存在一些挑战,本文最后展望了未来的研究方向。

关键词：区域医疗系统单体医院交通系统抗震韧性功能评估恢复时间

Silylamido supported dinitrogen heterobimetallic complexes: syntheses and their catalytic ability

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National Science Review 2021年第12期8卷 29-36页

作者： Dan-dan zhai Si-jun Xie yi Xia Hua-yi Fang Zhang-jie Shi Department of Chemistry Fudan University State Key Laboratory of Organometallic Chemistry Shanghai Institute of Organic ChemistryChinese Academy of Sciences

Molybdenum dinitrogen complexes supported by monodentate arylsilylamido ligand,[Ar(MeSi)N]MoNMg(THF)[N(SiMe)Ar](5) and [Ar(MeSi)N]MoNSiMe(6)(Ar=3,5-MeCH) were synthesized and structurally characterized,and proved to be effective catalysts for the disproportionation of cyclohexadienes and isomerization of terminal ***~1 H NMR spectrum suggested that the bridging nitrogen ligand remains intact during the catalytic reaction,indicating possible catalytic ability of the Mo-N=N motif.

关键词： dinitrogen fixation dinitrogen-metal complex catalytic ability disproportionation isomerization

Maintaining moderate levels of hypochlorous acid promotes neural stem cell proliferation and differentiation in the recovery phase of stroke

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Neural Regeneration Research 2025年第3期20卷 845-857页

作者： Lin-Yan Huang yi-De Zhang jie Chen Hai-Di Fan Wan Wang Bin Wang Ju-Yun Ma Peng-Peng Li Hai-Wei Pu Xin-yian Guo Jian-Gang Shen Su-Hua Qi School of Medical Technology Xuzhou Key Laboratory of Laboratory DiagnosticsXuzhou Medical UniversityXuzhouJiangsu ProvinceChina School of Pharmacy Xuzhou Medical UniversityXuzhouJiangsu ProvinceChina Department of Laboratory Medicine Branch Hospital of Huai’an First People’s HospitalHuai’anJiangsu ProvinceChina Department of Laboratory Medicine the Affiliated Hospital of Xuzhou Medical UniversityXuzhouJiangsu ProvinceChina School of Chinese Medicine The University of Hong KongHong Kong Special Administrative RegionChina

It has been shown clinically that continuous removal of ischemia/reperfusion-induced reactive oxygen species is not conducive to the recovery of late ***,previous studies have shown that excessive increases in hypochlorous acid after stroke can cause severe damage to brain *** previous studies have found that a small amount of hypochlorous acid still exists in the later stage of stroke,but its specific role and mechanism are currently *** simulate stroke in vivo,a middle cerebral artery occlusion rat model was established,with an oxygen-glucose deprivation/reoxygenation model established in vitro to mimic *** found that in the early stage(within 24 hours)of ischemic stroke,neutrophils produced a large amount of hypochlorous acid,while in the recovery phase(10 days after stroke),microglia were activated and produced a small amount of hypochlorous ***,in acute stroke in rats,hypochlorous acid production was prevented using a hypochlorous acid scavenger,taurine,or myeloperoxidase inhibitor,4-aminobenzoic acid *** results showed that high levels of hypochlorous acid(200μM)induced neuronal apoptosis after oxygen/glucose deprivation/***,in the recovery phase of the middle cerebral artery occlusion model,a moderate level of hypochlorous acid promoted the proliferation and differentiation of neural stem cells into neurons and *** suggests that hypochlorous acid plays different roles at different phases of cerebral ischemia/reperfusion *** levels of hypochlorous acid(5 and 100μM)promoted nuclear translocation ofβ-*** transfection of single-site mutation plasmids,we found that hypochlorous acid induced chlorination of theβ-catenin tyrosine 30 residue,which promoted nuclear ***,our study indicates that maintaining low levels of hypochlorous acid plays a key role in the recovery of neurological function.

关键词： cell differentiation cerebral ischemia/reperfusion injury chlorination hypochlorous acid microglia neural stem cell neurogenesis nuclear translocation stroke β-catenin

Optimal resource allocation scheme for cognitive radio networks with relay selection based on game theory

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The Journal of China Universities of Posts and Telecommunications 2012年第6期19卷 25-28,62页

作者： zhai Lan-jie JI Hong LI Xi TANG yi-wen School of Information and Communication Engineering Beijing University of Posts and Telecommunications

In this paper, we present a non-transferable utility coalition graph game （NTU-CGG） based resource allocation scheme with relay selection for a downlink orthogonal frequency division multiplexing （OFDMA） based cognitive radio networks to maximize both system throughput and system faimess. In this algorithm, with the assistance of others SUs, SUs with less available channels to improve their throughput and fairness by forming a directed tree graph according to spectrum availability and traffic demands of SUs. So this scheme can effectively exploit both space and frequency diversity of the system. Performance results show that, NTU-CGG significantly improves system faimess level while not reducing the throughput comparing with other existing algorithms.

关键词： cooperative relaying cognitive radio networks relay selection and resource allocation coalition graph game

The corrosion of AA2037 aluminum alloy in alkaline aqueous solution studied using slow positron beam spectroscopy

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Nuclear Science and Techniques 2016年第2期27卷 6-13页

作者： Jiao-Jiao Wang Zhe-jie Zhu Wei Yang yi-Chu Wu Tong-Guang zhai Hubei Key Laboratory of Nuclear Solid Physics School of Physics and Technology Wuhan University Chemical and Materials Engineering Department University of Kentucky

Corrosion behavior of AA2037 T8 Al alloy in a1 M Na OH aqueous solution was investigated using slow positron beam, together with microscopy techniques and electrochemical tests. The alloy was homogenized at 510℃ for 2 h and 30 s, respectively, before final peak aging, so that one Sample A had more dispersoids than Sample B after homogenization. It was found that S parameter of the Doppler-broadened annihilation was significantly decreased near the surface in both samples in the alkaline solution. With increasing the dissolution time,Sample A showed a slower decrease rate than Sample B,which might imply that the preexistence of more dispersoids might hinder the corrosion process in Sample *** electron microscopy and atomic force microscopy observations found that the surfaces of both samples were uniformly thinned due to intense chemical dissolution by the attack of OH-. With increasing the dissolution time,Sample B was corroded more substantially and produced more and larger pits in a short dissolution time than Sample A. Furthermore, polarization curves showed that Sample A had a lower corrosion current and corrosion rate than Sample B, which revealed that the presence of the dispersoids was responsible for the better corrosion resistance in the alloy.

关键词：慢正电子束碱性水溶液腐蚀行为铝合金扫描电子显微镜光谱溶解时间电化学测试

Corrosion mechanism research and microstructure analysis of Baosteel No.3 blast furnace hearth

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Journal of Iron and Steel Research International 2017年第10期24卷 1016-1022页

作者： Xun-fu Wang Qi-jie zhai School of Materials Science and Engineering Shanghai University Ironmaking Plant of Baoshan Iron & Steel Co. Ltd.

Baosteel No.3 blast furnace hearth was divided into tuyere area,taphole area,taphole upper side wall and taphole lower side wall according to different working *** chemical composition analysis,scanning electron microscopy,X-ray diffraction,energy dispersive spectrometry and other means,chemical composition and microstructure of different parts of hearth carbon brick were analyzed and markedly different corrosion mechanisms of these areas were *** element in form of ZnO mainly deposited on the hot side of carbon *** was no obvious evidence that Zn permeates into carbon bricks and erodes *** for taphole area,K,Na,and Fe contents from hot side to cold side gradually rise and fall,resulting in the decrease of apparent porosity,the increase of density and the higher thermal conductivity compared with those of new carbon *** higher content of Fe in carbon brick leads to more serious erosion because Fe has greatly changed the physical properties of carbon *** the taphole area,the contents of Si and Al present obvious concentration gradient because of the mechanical souring of molten iron and *** SiO;and Al;O;particles that have different expansion factors with carbon brick damaged the carbon substrate because of temperature *** graphitized carbon found on H4 where is the most serious corrosion site means that the carbon brick ever directly contacts with molten iron.

关键词： Blast furnace side wall Chemical component Mierostructure Corrosion

Noether Theorem for Generalized Birkhoffian Systems with Time Delay

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Transactions of Nanjing University of Aeronautics and Astronautics 2018年第3期35卷 507-515页

作者： zhai Xianghua Zhang yi School of Science Nanjing University of Science and TechnologyNanjing 210094 P.R.China School of Civil Engineering Suzhou University of Science and TechnologySuzhou 215009P.R.China

The Noether symmetries and the conserved quantities for generalized Birkhoffian systems with time delay are ***,the generalized Pfaff-Birkhoff principle with time delay is proposed,and the generalized Birkhoff's equations with time delay are ***,the generalized Noether quasi-symmetric transformations of the system are defined,and the criterion of the Noether symmetries is *** the Noether theorem for generalized Birkhoffian systems with time delay is ***,by imposing restrictions of constraints on the infinitesimal transformations,the Noether theorem of constrained Birkhoffian systems with time delay is *** example is given to illustrate the application of the results.

关键词： time delay generalized Birkhoffian system Noether symmetry conserved quantity

Thermodynamics and kinetics of extracting zinc from zinc oxide ore by the ammonium sulfate roasting method

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International Journal of Minerals,Metallurgy and Materials 2015年第5期22卷 467-475页

作者： yi Sun Xiao-yi Shen Yu-chun zhai School of Materials and Metallurgy Northeastern University

Thermodynamic analyses and kinetic studies were performed on zinc oxide ore treatment by （NH4）2SO4 roasting technology. The results show that it is theoretically feasible to realize a roasting reaction between the zinc oxide ore and （NH4）2SO4 in a temperature range of 573-723 K. The effects of reaction temperature and particle size on the extraction rate of zinc were also examined. It is found that a surface chemical reaction is the rate-controlling step in roasting kinetics. The calculated activation energy of this process is about 45.57 kJ/mol, and the kinetic model can be expressed as follows： 1 - （1 - α）1/3 = 30.85 exp（-45.57/RT）·t. An extraction ratio of zinc as high as 92% could be achieved under the optimum conditions.

关键词： zinc metallurgy extraction ammonium sulfate ore roasting thermodynamics kinetics