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Chinese Journal of Structural Chemistry 2019年第8期38卷 1320-1328页

作者： WANG min zhao Hua School of Science Beijing Technology and Business UniversityBeijing 100048China

Using transition-metal-complex cation as the structure-directing agent, a novel one-dimensional(1D) iodoargentate-based hybrid, namely, {[Co(2,2’-bipy)3]2(Ag7I11)·3H2O}n(1) has been synthesized and structurally characterized. The interesting 1D(Ag7I11)n4n- chain of 1 is constructed from a heptameric Ag7I13 secondary building unit, in which abundant argentophilic interactions can be observed. Intermolecular C–H···π among [Co(2,2’-bipy)3]2+ cations and C–H···I interactions between [Co(2,2’-bipy)3]2+ cations and(Ag7I11)n4n- chains contribute to the formation of a 3D network. The optical gap(2.58 eV) based on UV-Vis diffuse-reflectance measurement suggests the semiconductor nature of 1, which implies an efficient photocatalytic degradation activity on organic pollutants under visible light irradiation. As expected, 1 exhibits photocatalytic activity for the degradation of rhodamine B. The luminescence property was also studied.

关键词： organic-inorganic hybrid iodoargentate photocatalytic degradation

Global Phase Portraits of Uniform Isochronous Centers System of Degree Six with Polynomial Commutator

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Acta Mathematicae Applicatae Sinica 2024年第3期40卷 577-599页

作者： Li-na GUO ai-yong CHEN Shuai-feng zhao School of Mathematics and Statistics Henan University of Science and TechnologyLuoyang 471023China Department of Mathematics Hunan First Normal UniversityChangsha 410205China School of Mechatronics Engineering Henan University of Science and TechnologyLuoyang 471023China

This paper studies the global phase portraits of uniform isochronous centers system of degree six with polynomial *** systems have the form x=-y+xf(x,y),y=x+yf(x,y),where f(x,y)=a_(1)x+a_(2)xy+a_(3)xy^(2)+a_(4)xy^(3)+a_(5)xy^(4)=xσ(y),and any zero of 1+a_(1)y+a_(2)y^(2)+a_(3)y^(3)+a_(4)y^(4)+a_(5)y^(5),y=y is an invariant straight *** last,all global phase portraits are drawn on the Poincare disk.

关键词： global phase portraits uniform isochronous center polynomial commutator invariant straight lines

基于“微生物-肠-脑轴”探讨补肾通腑方对APP/PS1小鼠肠道菌群及LPS/TLR4/NF-κB通路的影响

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中国药理学通报 2025年第1期41卷 171-178页

作者：王旭张杰赵敏宋晓雨段建平河南中医药大学第一附属医院脑病科河南郑州450000 河南中医药大学第一临床医学院河南郑州450000 中西医防治重大疾病河南省协同创新中心河南郑州450046

目的探讨补肾通腑方调控肠道菌群,改善阿尔茨海默病(Alzheimer’s disease,AD)模型小鼠学习记忆能力的作用机制。方法以APP/PS1小鼠为研究对象,给予补肾通腑方治疗8周,采用Morris水迷宫法观察小鼠空间学习记忆能力变化;16S rDNA检测小... 详细信息

目的探讨补肾通腑方调控肠道菌群,改善阿尔茨海默病(Alzheimer’s disease,AD)模型小鼠学习记忆能力的作用机制。方法以APP/PS1小鼠为研究对象,给予补肾通腑方治疗8周,采用Morris水迷宫法观察小鼠空间学习记忆能力变化;16S rDNA检测小鼠肠道菌群丰度、多样性变化;HE染色观察海马病理形态学变化;免疫荧光检测海马区小胶质细胞活化情况;Western blot检测TLR4、NF-κB、IL-6等炎症因子表达。结果与模型组相比,补肾通腑方可以缩短AD模型小鼠逃避潜伏期、游泳路径,增加跨越平台次数(P<0.05),提升肠道菌群多样性,调节肠道菌群丰度,促进海马神经元细胞损伤修复,降低iNOS/Iba1共表达,提高Arg1/Iba1共表达(P<0.01),促进小胶质细胞从M1型向M2型转化,下调TLR4、NF-κB、IL-6等促炎因子的表达。结论补肾通腑方改善AD模型小鼠学习记忆能力的作用机制可能与调节肠道菌群介导的LPS/TLR4/NF-κB通路,从而抑制促炎型小胶质细胞活化、减轻中枢神经系统炎症、改善海马区神经元细胞损伤有关。

关键词：阿尔茨海默病补肾通腑方肠道菌群 LPS/TLR4/NF-κB通路 16S rDNA 微生物-肠-脑轴

Ultra-precision machining of cerium-lanthanum alloy with atmosphere control in an auxiliary device

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Nanotechnology and Precision Engineering 2022年第3期5卷 30-35页

作者： Chenyu zhao Shengjie Wu min Lai State Key Laboratory of Precision Measuring Technology and Instruments Laboratory of Micro/Nano Manufacturing TechnologyTianjin UniversityTianjin 300072China

Cerium–lanthanum alloys are the main component of nickel–metal hydride batteries,and they are thus an important material in the greenenergy ***,these alloys have very strong chemical activity,and their surfaces are easily oxidized,leading to great difficulties in their *** improve the corrosion resistance of cerium–lanthanum alloys,it is necessary to obtain a nanoscale surface with low ***,these alloys can easily succumb to spontaneous combustion during ***,to inhibit the occurrence of fire,machining of this alloy in ambient air needs to be conducted at very low cutting speeds while spraying the workpiece with a large amount of cutting ***,this is inefficient,and only a very limited range of parameters can be optimized at low cutting speeds;this restricts the optimization of other cutting *** achieve ultraprecision machining of cerium–lanthanum alloys,in this work,an auxiliary machining device was developed,and its effectiveness was *** results show that the developed device can improve the cutting speed and obtain a machined surface with low *** device can also improve the machining efficiency and completely prevent the occurrence of spontaneous *** was found that the formation of a build-up of swarf on the cutting tool is eliminated with high-speed cutting,and the surface roughness(Sa)can reach 5.64 nm within the selected ***,the oxidation processes of the cerium–lanthanum alloy and its swarf were studied,and the process of the generation of oxidative products in the swarf was *** results revealed that most of the intermediate oxidative products in the swarf were Ce^(3+),there were major oxygen vacancies in the swarf,and the final oxidative product was Ce^(4+).

关键词： Cerium–lanthanum alloy Ultraprecision machining Surface roughness Atmosphere control

Saddle pulmonary embolism is not a sign of high-risk deterioration in non-high-risk patients: A propensity score-matched study

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World Journal of Emergency Medicine 2021年第4期12卷 261-267页

作者： Dong Jia Chao Ji min zhao Department of Emergency Medicine Shengjing Hospital of China Medical UniversityShenyang 110004China Department of Clinical Epidemiology Shengjing Hospital of China Medical UniversityShenyang 110004China

BACKGROUND: There is controversy regarding whether saddle main pulmonary artery(MPA) embolism represents a high risk of deterioration in non-high-risk acute pulmonary embolism(PE) patients. This study aims to address this issue by conducting a propensity score matching(PSM) ***: A total of 727 non-high-risk acute PE patients were retrospectively evaluated. We evaluated the Bova score and risk stratification to examine the risk of deterioration. Deterioration defined as any adverse event within 30 days after admission. Computed tomographic pulmonary angiography was used to identify the embolism type. All patients were matched into four subgroups by PSM according to age, sex, Bova score, and risk stratification:(1) MPA and non-MPA embolism;(2) non-saddle MPA and non-MPA embolism;(3) saddle MPA and non-saddle MPA embolism;(4) saddle MPA and non-MPA embolism. Correlations were analyzed using Cox regression analysis, and deterioration risk was compared between subgroups using Kaplan-Meier ***: Cox regression analysis revealed that MPA embolism was correlated with deterioration, regardless of whether saddle MPA embolism was included or excluded. Saddle MPA embolism was not correlated with deterioration, regardless of comparison with non-saddle MPA embolism or non-MPA embolism. Patients with MPA and non-saddle MPA embolism presented a high risk for deterioration(logrank test=5.23 and 4.70, P=0.022 and 0.030, respetively), while patients with saddle MPA embolism were not at a high risk of deterioration(log-rank test=1.20 and 3.17, P=0.729 and 0.077, respetively).CONCLUSIONS: Saddle MPA embolism is not indicative of a high risk of deterioration in nonhigh-risk acute PE patients.

关键词： Main pulmonary artery Pulmonary embolism Computerized tomography pulmonary arteriography

Probing the Kinematic Signatures of Planet Formation in the Gas Disk of MWC 480

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Research in Astronomy and Astrophysics 2024年第6期24卷 110-118页

作者： min zhao Haochuan Yu Zhengxiang Li Department of Astronomy Beijing Normal UniversityBeijing 100875China Sub-department of Astrophysics Department of PhysicsUniversity of OxfordOxfordOX13RHUK

The disk around MWC 480 has shown multiple substructures in both dust and gas observations,possibly suggesting ongoing planet formation in *** this paper,we explore the gas kinematics of the MWC 480 disk by analyzing the archival Atacama Large Millimeter/submillimeter Array observations of^(12)CO(J=2-1),^(13)CO(J=2-1),and C^(18)O(J=2-1).By modeling the line-of-sight velocities,inferred from the Doppler shifts of the emission lines,we are able to decompose the three-dimensional(3D)velocity field of the disk into rotational,radial,and vertical *** analysis reveals the presence of large-scale gas flows in the(r,z)***,we identify potential meridional flows across various heights as traced by all three CO isotopologues in the 80–120 au region,possibly associated with ongoing planet formation activities in this ***,we find upward flows near 200 au for all three CO isotopologues,which may point to the presence of disk winds.

关键词： protoplanetary disks planet-disk interactions planet-star interactions

Frontier studies on natural products:moving toward paradigm shifts

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Science China Chemistry 2023年第4期66卷 928-942页

作者： Jin-Xin zhao Jian-min Yue State Key Laboratory of Drug Research Shanghai Institute of Materia MedicaChinese Academy of SciencesShanghai 201203China Shandong Laboratory of Yantai Drug Discovery Bohai Rim Advanced Research Institute for Drug DiscoveryYantai 264117China

1 Introduction Natural products(NPs)historically serve as a valuable and productive source of bioactive compounds for drug *** discovery of a range of alkaloids in the early1800s,including strychnine,morphine,etc.,her... 详细信息

关键词： alkaloids moving compounds

Composite quantile regression estimation for P-GARCH processes

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Science China Mathematics 2016年第5期59卷 977-998页

作者： zhao Biao CHEN zhao TAO GuiPing CHEN min Department of Statistics and Finance University of Science and Technology of China Department of Statistics Pennsylvnia State University School of Statistics Capital University of Economics and Business Academy of Mathematics and Systems Science Chinese Academy of Sciences

We consider the periodic generalized autoregressive conditional heteroskedasticity(P-GARCH) process and propose a robust estimator by composite quantile regression. We study some useful properties about the P-GARCH model. Under some mild conditions, we establish the asymptotic results of proposed *** Monte Carlo simulation is presented to assess the performance of proposed estimator. Numerical study results show that our proposed estimation outperforms other existing methods for heavy tailed *** proposed methodology is also illustrated by Va R on stock price data.

关键词： composite quantile regression periodic GARCH process strictly periodic stationarity strong consistency asymptotic normality

Activity Model of Fe-Si-B Ternary Metallic Melts

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Journal of Iron and Steel Research International 2011年第6期18卷 16-21页

作者： zhao Ding-guo GUO Pei-min zhao Pei State Key Laboratory for Advanced Iron and Steel Processes and Materials Central Iron andSteel Research Institute Beijing 100081 China

According to the ion and molecule coexistence theory, the activity model of Fe-Si-B ternary system was es- tablished, and the influence of ratio ：Csi/XZe, boron content and temperature, etc. on the activity of the melt com- pound was investigated. The results show that the FeB activity is high in the liquid iron, when Xsl/XFo is 0. 5 ; the ac- tivity of boron increases with increasing the boron content for different contents of xe and xs, and the activity of boron at the ratio xFo = 0.4 is about one order of magnitude higher than that for the XFo = 0. 8; The activities of the melt compound were also affected by temperature, but the influencing extent was little. The equal activity diagrams of silicon and boron were drawn for the first time according to the model results.

关键词： activity metallic melt ion and molecule coexistence model equal activity diagram

AoA-Based Channel Estimation for Massive MIMO OFDM Communication Systems on High Speed Rails

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China Communications 2020年第3期17卷 90-100页

作者： Yanrong zhao Wenjing zhao Gongpu Wang Bo ai Hervin Hidayat Putra Bagus Juliyanto School of Computer and Information Technology Beijing Jiaotong UniversityBeijing 100044China the State Key Laboratory of Rail Traffic Control and Safety Beijing Jiaotong UniversityBeijing 100044China School of Electrical Engineering and Informatics Bandung Institute of TechnologyBandungIndonesia

Channel estimation is a well-known challenge for wireless orthogonal frequency division multiplexing(OFDM)communication systems with massive antennas on high speed rails(HSRs).This paper investigates this problem and design two practicable uplink and downlink channel estimators for orthogonal frequency division multiplexing(OFDM)communication systems with massive antenna arrays at base station on ***,we first use pilots to estimate the initial angle of arrival(AoA)and channel gain information of each uplink path through discrete Fourier transform(DFT),and then refine the estimates via the angle rotation technique and suggested pilot *** on the uplink angel estimation,we design a new downlink channel estimator for frequency division duplexing(FDD)***,we derive the Cramér-Rao lower bounds(CRLBs)of the AoA and channel gain ***,numerical results are provided to corroborate our proposed studies.

关键词： massive MIMO high speed rail channel estimation AoA OFDM