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Based on non-targeted metabolomics for differential components screening of Rosae Chinensis Flos and Rosae Rugosae Flos and their quality evaluation

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Traditional Medicine Research 2025年第2期10卷 1-15页

作者： Xu liang Ni-hui Zhang Zhi-Lai Zhan Guang-Lu Chang Yan Gao Xia li Wen-Yuan Gao School of Pharmaceutical Science and Technology Faculty of MedicineTianjin UniversityTianjin 300193China State Key Laboratory for Quality Ensurance and Sustainable Use of Dao-di Herbs China Academy of Chinese Medical SciencesBeijing 100700China Key Laboratory of Modern Chinese Medicine Resources Research Enterprises Tianjin 300402China

Background:Rosa chinensis *** Rosa rugosa *** not only of ornamental value,but also edible flowers and the flower buds have been listed in the Chinese Pharmacopoeia as traditional *** two plants have some differences in efficacy,but the flower buds are easily confused for similar *** addition,large-scale cultivation of ornamental rose flowers may lead to a decrease in the effective components of medicinal ***,it is necessary to study the chemical composition and make quality evaluation of Rosae Chinensis Flos(Yueji)and Rosae Rugosae Flos(Meigui).Methods:In this study,40 batches of samples including Meigui and Yueji from different regions in China were collected to establish high-performance liquid chromatography ***,the fingerprints data was analyzed using principal component analysis,hierarchical cluster analysis,and partial least squares discriminant analysis analysis chemometrics to obtain information on intergroup differences,and non-targeted metabolomic techniques were applied to identify and compare chemical compositions of samples which were chosen from groups with large *** compounds were screened by orthogonal partial least-squares discriminant analysis and S-plot,and finally multi-component quantification was performed to comprehensively evaluate the quality of Yueji and ***:The similarity between the fingerprints of 40 batches roses and the reference print R was 0.73 to 0.93,indicating that there were similarities and differences between the *** principal component analysis and hierarchical cluster analysis of fingerprints data,the samples from different origins and varieties were intuitively divided into four *** least-squares discriminant analysis analysis showed that Meigui and Yueji cluster into two categories and the model was reliable.A total of 89 compounds were identified by high resolution mass spectrometry,mainly were flavonoids and flavon

关键词： Rosa chinensis Jacq. Rosa rugosa Thunb. metabolomics chemometrics multiple component quantification quality evaluation

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Persistent alterations in gray matter in COVID-19 patients experiencing sleep disturbances:a 3-month longitudinal study

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Neural Regeneration Research 2025年第10期20卷 3013-3024页

作者： Kaixuan Zhou Gaoxiong Duan Ying liu Bei Peng Xiaoyan Zhou lixia Qin lingyan liang Yichen Wei Qingping Zhang Xiaocheng li Haixia Qin Yinqi Lai Yian Lu Yan Zhang Jiazhu Huang Jinli Huang Yinfei Ouyang Bolin bin Mingming Zhao Jun liu Jianrong Yang Demao Deng Guangxi Key Laboratory of Special Biomedicine School of MedicineGuangxi UniversityNanningGuangxi Zhuang Autonomous RegionChina Department of Radiology the People’s Hospital of Guangxi Zhuang Autonomous RegionGuangxi Academy of Medical SciencesNanningGuangxi Zhuang Autonomous RegionChina Department of Sleep Medicine the People’s Hospital of Guangxi Zhuang Autonomous RegionNanningGuangxi Zhuang Autonomous RegionChina Department of Radiology The Second Xiangya HospitalCentral South UniversityChangshaHunan ProvinceChina Guangxi Clinical Research Center for Sleep Medicine the People’s Hospital of Guangxi Zhuang Autonomous RegionNanningGuangxi Zhuang Autonomous RegionChina

Sleep disturbances are among the most prevalent neuropsychiatric symptoms in individuals who have recovered from severe acute respiratory syndrome coronavirus 2 *** studies have demonstrated abnormal brain structures in patients with sleep disturbances who have recovered from coronavirus disease 2019(COVID-19).However,neuroimaging studies on sleep disturbances caused by COVID-19 are scarce,and existing studies have primarily focused on the long-term effects of the virus,with minimal acute phase *** a result,little is known about the pathophysiology of sleep disturbances in the acute phase of *** address this issue,we designed a longitudinal study to investigate whether alterations in brain structure occur during the acute phase of infection,and verified the results using 3-month follow-up data.A total of 26 COVID-19 patients with sleep disturbances(aged 51.5±13.57 years,8 women and 18 men),27 COVID-19 patients without sleep disturbances(aged 47.33±15.98 years,9 women and 18 men),and 31 age-and gender-matched healthy controls(aged 49.19±17.51 years,9 women and 22 men)were included in this *** COVID-19 patients with sleep disturbances were included in a longitudinal *** found that COVID-19 patients with sleep disturbances exhibited brain structural changes in almost all brain *** cortical thicknesses of the left pars opercularis and left precuneus were significantly negatively correlated with Pittsburgh Sleep Quality Index ***,we observed changes in the volume of the hippocampus and its subfield regions in COVID-19 patients compared with the healthy *** 3-month follow-up data revealed indices of altered cerebral structure(cortical thickness,cortical grey matter volume,and cortical surface area)in the frontal-parietal cortex compared with the baseline in COVID-19 patients with sleep *** findings indicate that the sleep disturbances patients had altered morphology in the cortical an

关键词： brain structure cortical gray matter volume cortical surface area cortical thickness hippocampus magnetic resonance imaging Pittsburgh Sleep Quality Index severe acute respiratory syndrome coronavirus 2 infections sleep disturbances sub-cortical volume

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新时期我国职业体育改革与发展的宏观对策

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河北体育学院学报 2017年第4期31卷 10-15页

作者：金宗强姜卫芬马斌虎李会超天津体育学院天津300381 天津医科大学天津300070 天津中德应用技术大学天津300350 中国民航大学天津300300

运用文献资料法和逻辑分析法,在对新时期我国职业体育发展面临的社会、体制、产业三大新背景变化进行客观分析的基础上,拟订出新时期促进我国职业体育改革与发展的宏观对策。一是借力我国良好的社会发展氛围,发挥职业体育"中枢纽带"作用... 详细信息

运用文献资料法和逻辑分析法,在对新时期我国职业体育发展面临的社会、体制、产业三大新背景变化进行客观分析的基础上,拟订出新时期促进我国职业体育改革与发展的宏观对策。一是借力我国良好的社会发展氛围,发挥职业体育"中枢纽带"作用,有效拓展其功能领域并加大功能开发力度;二是依托我国体育体制转型,发挥市场在资源配置中的决定性作用,加快"管办分离",逐步建立"小政府、大社会、多元化"的发展格局及"政府拉动、市场驱动、社会互动"的发展模式;三是夯实产业发展资金基础、人才基础、市场基础和政策基础。

关键词：中国职业体育改革市场资金人才政策

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Microstructure and Mechanical Properties of TWIP Steel Joints

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Journal of Iron and Steel Research International 2014年第8期21卷 749-756页

作者： li-li MA Ying-hui WEI li-feng HOU bin YAN College of Materials and Engineering Taiyuan University of Technology

As a new type of high manganese steel, the twinning induced plasticity （TWIP） steels have attracted a growing interest in the automotive industry due to their good performance. Thin plates of TWIP steel were welded by laser beam welding （LBW） and gas tungsten arc welding （GTAW）. The microstructure result shows that GTAW joint has obvious heat-affected zone （HAZ）, while the HAZ of LBW joint is almost invisible. The X-ray diffraction result shows that the phase compositions of both joints are austenitic and no phase transition occurs. Energy disper- sive spectrometry result shows that there is violent evaporation of Mn element in LBW joint, while the proportion of Mn element in GTAW joint is almost unchanged. Tensile tests and micro-hardness measurements were performed to take into account the mechanical properties of joints manufactured by the two different processes. The micro-hard- ness profiles of both joints present a typical saddle distribution, and the hardness of GTAW seam is lower than that of LBW seam. The failure positions of LBW joints are all located in base metal while the GTAW joints are all at the weld toe due to the softening of HAZ. By means of scanning electron microscopy, a typical ductile fracture is observed in LBW joint, while a brittle fracture with quasi-cleavage fracture characteristic is observed in GTAW joint.

关键词： TWIP steels high manganese steels LBW GTAW

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Association between the infection probability of COVID-19 and ventilation rates:An update for SARS-CoV-2 variants

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Building Simulation 2023年第1期16卷 3-12页

作者： hui Dai bin Zhao Departmentof Building Science School of ArchitectureTsinghua UniversityBeijing 100084China Beijing Key Laboratory of Indoor Air Quality Evaluation and Control Tsinghua UniversityBeijing 100084China

Severe acute respiratory syndrome coronavirus 2(SARS-CoV-2),the cause of the current coronavirus disease 2019(COVID-19)pandemic,is ***,the risk of airborne transmission in confined spaces may be higher,and corresponding precautions should be ***,we obtained the quantum generation rate(q)value of three SARS-CoV-2 variants(Alpha,Delta,and Omicron)for the Wells-Riley equation with a reproductive number-based fitted approach and estimated the association between the infection probability and ventilation *** q value was 89–165 h^(−1)for Alpha variant,312–935 h^(−1)for Delta variant,and 725–2,345 h^(−1)for Omicron *** ventilation rates increased to ensure an infection probability of less than 1%,and were 8,000–14,000 m^(3)h^(−1),26,000–80,000 m^(3)h^(−1),and 64,000–250,000 m^(3)h^(−1)per infector for the Alpha,Delta,and Omicron variants,*** the infector and susceptible person wore N95 masks,the required ventilation rates decreased to about 1/100 of the values required without masks,which can be achieved in most typical *** air purifier was ineffective for reducing transmission when used in scenarios without *** prolonged exposure time in confined spaces remains critical in reducing the risk of airborne transmission for highly contagious SARS-CoV-2 variants.

关键词： COVID-19 SARS-CoV-2variants mask ventilation air purifier

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A Facile Synthetic Approach to Reduced Graphene Oxide-Fe_3O_4 Composite as High Performance Anode for lithium-ion Batteries

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Journal of Materials Science & Technology 2014年第8期30卷 759-764页

作者： Yanhong Chang Jing li bin Wang hui Luo linjie Zhi School of Civil and Environmental Engineering University of Science and Technology Beijing Key Laboratory of Educational Ministry for High Efficient Mining and Safety in Metal Mine University of Science and Technology Beijing National Center for Nanoscience and Technology School of Chemical and Biological Engineering University of Science and Technology Beijing

Reduced graphene oxide-Fe3O4（rGO—Fe3O4） composite has been prepared via a facile and effective hydrothermal method by synthesizing Fe3O4 nanospheres on the planes of reduced graphene oxide（rGO）.Characterizations suggest the successful attachment of Fe3O4 nanospheres to rGO *** rGO—Fe3O4composite（66.7 wt%of Fe3O4 in the composite） exhibits a stable capacity of 668 mAh g-1 without noticeable fading for up to 200 cycles in the voltage range of 0.001—3.0 V,and the superior performance of rGO-Fe3O4 is clearly established by comparison of the results with those from bare Fe3O4 nanospheres（capacity declined to 117 mAh g-1 only at the 200 th cycle）.The excellent electrochemical performance of rGO—Fe3O4 composite can be attributed to the fact that the uniform dispersion of the Fe3O4 nanospheres growing on the rGO sheets avoids aggregation during li uptake-release cycling,which is desired for cycle ***,the rGO sheets afford not only elastic buffer to alleviate the volume variations of Fe3O4nanospheres,but also good ionic and electronic transport medium in the electrode.

关键词： Facile synthetic approach rGO Fe3O4 nanosphcres Composite lithium-ion batteries High performance

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Stirring brazing of dissimilar Al/Mg alloy without flux in air

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Rare Metals 2013年第5期32卷 469-474页

作者： hui-bin Xu hui-bin Sun Hong-You Chen School of Materials Science and Engineering Chongqing University of Technology Chen State Key Laboratory of Advanced Welding and Joining Harbin Institute of Technology

AZ31B magnesium alloy and 2024 aluminum alloy were successfully jointed at aid of mechanical stirring with Sn-Zn-Al filler metal. The microstructure, fracture morphologies, and mechanical properties of joint were investigated. The results show that Mg-Al intermetallic compounds can be avoided by the process. But, a small quantity of porosity is found in the joint. The sheafing strength of joint interface adjacent to magnesium alloy is 35.4 MPa for formation of Mg-Sn intermetallic compounds, which is about 46 % of that of filler metal. While, the shearing strength of joint interfaces adjacent to aluminum alloy is 70.4 MPa for formation of Zn-Sn-Al solid solution, which is about 92 % of that of filler metal.

关键词： 2024 Al alloy AZ31B Mg alloy Stirring brazing

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Hollow carbon nanofibers with dynamic adjustable pore sizes and closed ends as hosts for high-rate lithiumsulfur battery cathodes

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Nano Research 2018年第3期11卷 1238-1246页

作者： Xiang-Qian Zhang bin He Wen-Cui li An-hui Lu State Key Laboratory of Fine Chemicals School of Chemical Engineering Faculty of Chemical Environmental and Biological Science and Technology Dalian University of Technology Linggong Road 2 Dalian 116024 China

Designing a better carbon framework is critical for harnessing the high theoretical capacity of li-S batteries and avoiding their drawbacks, such as the insulating nature of sulfur, active material loss, and the polysulfide shuttle reaction. Here, we report an ingenious design of hollow carbon nanofibers with closed ends and protogenetic mesopores in the shell that can be retracted to micropores after sulfur infusion. Such dynamic adjustable pore sizes ensure a high sulfur loading, and more importantly, eliminate excessive contact of sulfur species with the electrolyte. Together, the high aspect ratio and thin carbon shells of the carbon nanofibers facilitate rapid transport of li^＋ ions and electrons, and the closed-end structure of the carbon nanofibers further blocks polysulfide dissolution from both ends, which is remarkably different from that for carbon nanotubes with open ends. The obtained sulfur-carbon cathodes exhibit excellent performance marked by high sulfur utilization, superior rate capability （1,170, 1,050, and 860 mA.h.g-1 at 1.0, 2.0, and 4.0 C （1 C = 1.675 A·g^-1）, respectively）, and a stable reversible capacity of 847 mA·h·g^-1 after 300 cycles at a high rate of 2.0 C.

关键词： hollow carbon nanofibers pore-adjusting strateg sulfur cathodes rate capability energy materials

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An innovative process of clad teeming for preparing slab ingot

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Journal of Iron and Steel Research International 2022年第12期29卷 2006-2015页

作者： Wen-bin Ma Yao-hui Jin Yu-an Jing Wen-bin li Wei-da Yu Guang-long li Wan-ming li School of Materials and Metallurgy University of Science and Technology LiaoningAnshan 114051LiaoningChina Iron and Steel Research Institutes of Ansteel Group Corporation Anshan 114001LiaoningChina

An innovative process of clad teeming was proposed to prepare slab ingot,which featured a built-in cold core to inhibit solidification defects.A 20-kg clad ingot was prepared in the experiment,using a volume ratio of solid core to molten steel of 1:13 and a preheating temperature of cold core of 573 *** microstructures of the clad ingot were analyzed by comparing with a reference ingot without cold *** morphologies and mechanical properties of the clad ingot were studied before and after hot *** effect of cold core on heat transfer and nucleation during the solidification in clad ingot was *** show that the solidification microstructures in the clad ingot are refined and homogenized *** grain size in the center of the reference ingot is 2–3 times greater than that of clad ingot,and there is almost no columnar grain in the clad *** interfacial shear strength reaches 318 MPa,which shows excellent metallurgical bonding at the interface of cold core and molten *** defects at the interface are eliminated,and interfacial shear strength reaches 426 MPa after hot rolling with a 68.4%total reduction *** experiment and analysis of this process are expected to provide a new idea to prepare large ingots with refinement and homogeneity at a low cost.

关键词： Clad teeming Steel ingot Grain refinement Interface Cold core Interfacial mechanical property

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Wave action by arrays of vertical cylinders with arbitrary smooth cross-section

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Journal of Hydrodynamics 2020年第1期32卷 70-81页

作者： Jia-bin liu An-xin Guo Qing-he Fang hui li hui Hu Peng-fei liu Key Lab of Structures Dynamic Behavior and Conrol of the Ministry of Education Harbin Institute of Techno-logyHarbin 150090China Key Lab of Smart Prevention and Mitigation of Civil Engineering Disasters of the Ministry of Industry and Information Technology Harbin Institute of TechnologyHarbin 150090China Depariment of Aerospace Engineering lowa State UniversityAmeslowa 50011USA China Railway Bridge Science Research Institute LtdWuhan 430034China

This paper presents an analytical model to solve the linear wave diffraction problem by arrays of bottom-mounted cylinders with arbitrary smooth *** on the assumption of ideal fluid and potential theory,the unknown coefficients of total velocity potential can be solved by system of linear equations,which are obtained from the boundary *** accuracy of the present method is verified by comparing it with the numerical tool in terms of the wave force and wave *** cylinders with different configurations are tested,the cross-section of which is circular with cosine *** results show that the proposed method could obtain an accurate prediction of the wave action with multiple cylinder ***,the diffraction wave is investigated on arrays of bottom-mounted cylinders with different cross-section and *** near-trapping problem with effects of the multi-body interaction are also investigated.

关键词： Wave diffraction cylinder array arbitrary smooth cross-section analytical solution

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