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Alpha-decay properties of nuclei around neutron magic numbers

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Nuclear Science and Techniques 2025年第1期36卷 140-149页

作者： ming Li Chu-Xin Chen Lan-Fang Xiao yi Zhang song Luo Xiao-Hua Li School of Nuclear Science and Technology University of South ChinaHengyang 421001China PET‑CT Center Chenzhou First People’s HospitalChenzhou 423000China Hengyang Ecological Environment Monitor Center Hengyang 421001China China Certification and Inspection Group Hefei 230000China National Exemplary Base for International Science and Technology Collaboration of Nuclear Energy and Nuclear Safety University of South ChinaHengyang 421001China Cooperative Innovation Center for Nuclear Fuel Cycle Technology and Equipment University of South ChinaHengyang 421001China Key Laboratory of Low Dimensional Quantum Structures and Quantum Control Hunan Normal UniversityChangsha 410081China

By combining experimental α-decay energies and half-lives, the α-particle preformation factor for nuclei around neutron magic numbers N of 126, 152, and 162 were extracted using the two-potential approach. The nuclei around the shell closure were more tightly bound than adjacent nuclei. Additionally, based on the WS4 mass model (Wang et al., Phys. Lett.B 734, 215 (2014)), we extended the two-potential approach to predict the α-decay half-lives of nuclei around N values of178 and 184 with Z of 119 and 120. We believe that our findings will serve as guidelines for future experimental studies.

关键词： adecay Preformation factor Neutron magic number Heavy and superheavy nuclei

Seismic isolation design and resilience improvement of railway station considering the influence of near-fault pulse-like ground motions

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Earthquake Engineering and Engineering Vibration 2025年第1期24卷 257-270页

作者： Pan yi song Jiayu Chen Qi Liu Yongxin School of Civil Engineering Southwest Jiaotong UniversityChengdu 610031China Key Laboratory of Seismic Engineering of Sichuan Province Chengdu 610031China

To improve the resilience of railway stations,a typical station was selected as the research object,and an isolation design was ***-four groups of near-fault pulse-like ground motions were *** seismic resilience of the no-isolation railway stations(NIRS)and the isolation railway stations(IRS)were compared to provide a numerical result of the improvement in *** results show that in the station isolation design,the station's functional requirements and structural characteristics should be considered and the appropriate placement of isolation bearings is under the waiting *** the action of a rare earthquake,the repair cost,repair time,rate of harm and death of the IRS were decreased by 8.04 million,18.30 days,6.93×10^(-3)and 1.21×10^(-3),respectively,when compared to the *** IRS received a seismic resilience grade of three-stars and the NIRS only one-star,indicating that rational isolation design improves the seismic resilience of ***,for the design of stations close to earthquake faults,it is suggested to utilize appropriate isolation techniques to improve their seismic resilience.

关键词： railway station near-fault pulse-like ground motion isolation design seismic resilience resilience improvement

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新型双环减速器的设计与实验验证

重庆大学学报（自然科学版） 2010年第6期33卷 49-54页

作者：宋轶民刘聪张俊天津大学机械工程学院天津300072

设计了一种新型双环减速器,并对其进行相关实验验证。采用封闭图法确定减速器内啮合齿轮副的变位系数,进而完成了该型减速器的结构设计与运动学仿真。利用ANSYS的APDL编程语言建立了新型双环减速器样机的三维有限元模型,对其进行了模态... 详细信息

设计了一种新型双环减速器,并对其进行相关实验验证。采用封闭图法确定减速器内啮合齿轮副的变位系数,进而完成了该型减速器的结构设计与运动学仿真。利用ANSYS的APDL编程语言建立了新型双环减速器样机的三维有限元模型,对其进行了模态仿真与接触分析。结果表明,系统低阶固有频率远高于输入转频,其低阶振型依次表现为高速轴和输出轴在垂直和水平方向的弯曲;在额定载荷下共有3对轮齿发生接触,且最大应力远低于齿轮副的许用应力。样机负载运行和振动测试结果表明,新型双环减速器能在单、双轴驱动2种工况下运行;单轴驱动时,可利用非180°相位差克服机构的运动不确定性实现正常运转,而双轴驱动方式下的动力学性能较单轴驱动为好;减速器的传动效率随负载的增大而增加,且具有良好的短期过载能力。实验结果验证了所提方法能用于指导该型减速器的设计。

关键词：双环减速器有限元法模态分析应力分析传动效率

Radical dehydroxymethylative fluorination of aliphatic primary alcohols and diverse functionalization ofα-fluoroimides via BF_(3)·OEt_(2)-catalyzed C-F bond activation

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Chinese Chemical Letters 2025年第1期36卷 239-243页

作者： Peng Wang Jianjun Wang Ni song Xin Zhou ming Li Molecular Synthesis Center Key Laboratory of Marine MedicineChinese Ministry of EducationSchool of Medicine and PharmacyOcean University of ChinaQingdao 266003China Laboratory for Marine Drugs and Bioproducts Pilot National Laboratory for Marine Science and TechnologyQingdao 266237China

Ag_(2)CO_(3)-promoted dehydroxymethylative fluorination of aliphatic alcohols has been achieved with Selectfluor as both oxidant and fluorine *** reaction involvesβ-fragmentation of primary alkoxy radicals,followed by the fluorination of the resulting C-centered radical *** transformation proceeds under mild reaction conditions and exhibits a broad substrate scope,thus opening up a new entrance to the synthesis of fluorinated constructs includingα-fluoroimides and 1-fluoroalkyl benzoates as well as secondary and tertiary alkyl fluorides like versatile 2-fluoro-2-alkyl 1,3-propandiol *** divergent functionalization of the obtainedα-fluoroimides enables an efficient access to amine derivatives through C-F bond activation under the action of BF_(3)·OEt_(2).

关键词： Dehydroxymethylative fluorination Alkoxy radicals β-Fragmentation Silver catalysis C-F Bond activation

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间歇式反应釜温度串级预测函数控制

化学工程 2013年第10期41卷 63-68,74页

作者：邱爽宋一鸣西北大学化工学院陕西西安710069

采用先进预测函数控制(PFC)技术实现实验室规模釜式反应器温度的控制。借助于被控对象的参数模型,对在线不可能测量或很难得到的工艺参数进行了估算,设计并在可编程逻辑控制器(PLC)中实现了温度串级控制。通过修正内嵌参数模型,抵消了... 详细信息

采用先进预测函数控制(PFC)技术实现实验室规模釜式反应器温度的控制。借助于被控对象的参数模型,对在线不可能测量或很难得到的工艺参数进行了估算,设计并在可编程逻辑控制器(PLC)中实现了温度串级控制。通过修正内嵌参数模型,抵消了模型的不确定性和各种扰动对系统稳定性的影响。结果表明:PFC在控制过程中既能很好地兼顾被控系统中子单元的动态性能,又具有很理想的控制响应品质。

关键词：预测函数控制串级温度控制反应器

Adsorption and retention of fracturing fluid and its impact on gas transport in tight sandstone with different clay minerals

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Petroleum Science 2025年第1期22卷 370-383页

作者： yi-Jun Wang Li-Jun You Jian Yang yi-Li Kang ming-Jun Chen Jia-Jia Bai Jian Tian State Key Laboratory of Oil and Gas Reservoir Geology and Exploitation Southwest Petroleum University Engineering Technology Research Institute of Southwest Oil & Gas Field Company PetroChina School of Petroleum Engineering Changzhou University State Key Laboratory of Coal Mine Disaster Dynamics and Control Chongqing University

To elucidate the adsorption characteristics and retention mechanisms of fracturing fluids in diverse clay minerals, we conducted on-line nuclear magnetic resonance(NMR) and atomic force microscopy(AFM)experiments. The depth and extent of solid phase damage are determined by the ratio between the size of fine fractions in fracturing fluid residue and the pore-throat size in experiments. Poor physical properties(K 0.5 m D) combined with a scattered distribution of retained fracturing fluid is associated with high gas phase recovery permeability, whereas a continuous sheet-like distribution results in low recovery permeability. The expansive surface area and presence of filamentous illite minerals facilitate the multiple winding and adsorption of fracturing fluids, demonstrating strong hydrogen-bonding, multi-layering and multiple adsorption properties. The geological characteristics of the main gas formations exhibit significant variation, and the severity of damage caused by fracturing fluids occurs in diverse sequences. To address this issue, a differentiated strategy for optimizing fracturing fluids has been proposed.

关键词： Clay minerals Formation damage Fracturing fluid retention distribution Adsorption morphology

Palaeowind reconstruction from Lower Cretaceous wavedominated depositional records of the Tanan Depression,Northeast Asia

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Journal of Oceanology and Limnology 2025年第1期43卷 41-56页

作者： Xinyu XUE Zaixing JIANG Chao LIU Li WANG Huanyu XIE Lizhou song ming SU School of Marine Science Sun Yat-sen UniversityZhuhai 519083China School of Energy Resources China University of Geosciences(Beijing)Beijing 100083China Sinopec Matrix Corporation Qingdao 266000China Daqing Oilfield Production Technology Institute Daqing 163453China

Palaeowind regime is an important component for reconstructing palaeoclimate and understanding ancient global *** applied the beach-ridge thickness technique(BTT)and the longshore-bar thickness technique(LTT)to reconstruct the Early Cretaceous palaeowind velocities based on depositional records of Tanan Depression in Northeast *** thickness of beach ridges and nearshore bars is the most important parameter for applying the BTT and the LTT *** identified 22 beach ridges and 23 nearshore bars based on drilling cores and wireline-log data in the Tanan *** velocities calculated by using the LTT method ranged from 10.84 to 13.66 m/s,showing a narrower range than those calculated by using the BTT method(7.58–15.93 m/s).We further analyzed the underlying factors causing the difference between the results derived from these two methods based on the sedimentary process of the beach ridge and the nearshore *** reconstructed wind regime was assumed to be the summer monsoon originating from the Mongol-Okhotsk Ocean before it had been completely enclosed,which provides valuable insight into the understanding of the atmospheric circulation in Northeast Asia during the Early Cretaceous.

关键词： palaeowind beach ridge nearshore bar Early Cretaceous East Asia Summer Monsoon

Tanreqing Injection Inhibits Activation of NLRP3 Inflammasome in Macrophages Infected with Influenza A Virus by Promoting Mitophagy

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Chinese Journal of Integrative Medicine 2025年第1期31卷 19-27页

作者： LIU Tian-yi HAO Yu MAO Qin ZHOU Na LIU Meng-hua WU Jun WANG yi YANG ming-rui School of Life Sciences Beijing University of Chinese MedicineBeijing102488China Experimental Research Center China Academy of Chinese Medical SciencesBeijing100700China

Objective: To investigate the inhibitory effect of Tanreqing Injection(TRQ) on the activation of nucleotide-binding oligomerization domain-like receptor pyrin domain containing 3(NLRP3) inflammasome in macrophages infected with influenza A virus and the underlying mechanism based on mitophagy pathway. Methods:The inflammatory model of murine macrophage J774A.1 induced by influenza A virus [strain A/Puerto Rico/8/1934(H1N1), PR8] was constructed and treated by TRQ, while the mitochondria-targeted antioxidant Mito-TEMPO and autophagy specific inhibitor 3-methyladenine(3-MA) were used as controls to intensively study the anti-inflammatory mechanism of TRQ based on mitophagy-mitochondrial reactive oxygen species(mt ROS)-NLRP3 inflammasome pathway. The levels of NLRP3, Caspase-1 p20, microtubule-associated protein 1 light chain 3 Ⅱ(LC3Ⅱ) and P62 proteins were measured by Western blot. The release of interleukin-1β(IL-1β) was tested by enzyme linked immunosorbent assay, the mt ROS level was detected by flow cytometry, and the immunofluorescence and co-localization of LC3 and mitochondria were observed under confocal laser scanning microscopy. Results: Similar to the effect of Mito-TEMPO and contrary to the results of 3-MA treatment, TRQ could significantly reduce the expressions of NLRP3, Caspase-1 p20, and autophagy adaptor P62, promote the expression of autophagy marker LC3Ⅱ, enhance the mitochondrial fluorescence intensity, and inhibit the release of mt ROS and IL-1β(all Pming the type of mitophagy. Conclusion: TRQ could reduce the level of mt ROS by promoting mitophagy in macrophages infected with influenza A virus, thus inhibiting the activation of NLRP3 inflammasome and the release of IL-1β, and attenuating the inflammatory response.

关键词： Tanreqing Injection influenza virus anti-inflammation mitophagy nucleotide-binding oligomerization domain-like receptor pyrin domain containing 3 inflammasome Chinese medicine

Internal transcribed spacer sequencing to explore the intrinsic composition of fungal communities in fungal esophagitis

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World Journal of Gastroenterology 2025年第7期31卷 26-38页

作者： yi-Kang song Lin Zheng Ai-Xin Liu Jun-Ji Ma Department of Gastroenterology The Second Hospital of Hebei Medical UniversityHebei Key Laboratory of GastroenterologyHebei Institute of GastroenterologyHebei Clinical Research Center for Digestive DiseasesShijiazhuang050000Hebei ProvinceChina

BACKGROUND Fungal esophagitis(FE)is caused by fungal invasion of the esophageal *** endoscopy,the esophageal mucosa shows edema,congestion,erosion,and ulceration,and bleeds easily when touched,and the surface of the mucosa is covered with small white spots like"bean curd residue".Clinical cases showing typical FE under endoscopic imaging but negative esophageal mucosal brush(referred to as suspected FE)have increased the difficulty and challenge of clinical diagnosis and *** present,the esophageal fungal flora of suspected case has not been thoroughly *** To characterize the fungal flora in FE,suspected FE,and the esophageal normal controls(NCs),and to identify marker species to improve detection of *** This was a case-control study.A total of 19 patients with FE,16 with suspected FE,and 10 NCs were selected by *** esophageal cell brush samples of each group were sequenced by internal transcribed spacer(ITS)1 and analyzed by *** In FE and suspected FE patients,species richness,species diversity and species evenness,as measured by the Chao1 index,Shannon index and Pielou index,were lower than in the NCs,and the comparison between the FE and NCs was the most significant(P<0.05).Compared with the NCs,the relative abundance of Candida in FE and suspected FE patients was significantly increased(P<0.001),while the relative abundance of Yarrowia was significantly decreased(P<0.05).Moreover,Yarrowia abundance in the FE group was significantly lower than in the NCs and suspected FE groups(P<0.001).The area under the curve for Candida in FE and suspected FE patients was 99.5%(P<0.05)and 81.3%(P<0.05),***,compared with FE patients,the relative abundance of Ascomycota and Candida in the esophageal flora of suspected FE patients was decreased,while the relative abundance of Yarrowia,Thermomyces and Pichia was *** ITS showed that composition of the fungal community was similar in the F

关键词： Fungal microbiota Esophagitis Candida Yarrowia Biomarker