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αDecay in extreme laser fields within a deformed Gamow-like model

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Nuclear Science and Techniques 2024年第2期35卷 131-144页

作者： qiong Xiao Jun-Hao Cheng Yang-Yang Xu You-tian Zou Jun-Gang Deng Tong-Pu Yu Department of Physics National University of Defense TechnologyChangsha 410073China College of Science China Three Gorges UniversityYichang 443002China

In this study, the effect of extreme laser fields on the α decay process of ground-state even–even nuclei was investigated.Using the deformed Gamow-like model, we found that state-of-the-art lasers can cause a slight change in the α decay penetration probability of most nuclei. In addition, we studied the correlation between the rate of change of the α decay penetration probability and angle between the directions of the laser electric field and α particle emission for different nuclei. Based on this correlation, the average effect of extreme laser fields on the half-life of many nuclei with arbitrary α particle emission angles was calculated. The calculations show that the laser suppression and promotion effects on the α decay penetration probability of the nuclei population with completely random α particle-emission directions are not completely canceled.The remainder led to a change in the average penetration probability of the nuclei. Furthermore, the possibility of achieving a higher average rate of change by altering the spatial shape of the laser is explored. We conclude that circularly polarized lasers may be helpful in future experiments to achieve a more significant average rate of change of the α decay half-life of the nuclei population.

关键词： αDecay Deformed Gamow-like model Half-lives Extreme laser field Penetration probability

VX-509 attenuates the stemness characteristics of colorectal cancer stem-like cells by regulating the epithelial-mesenchymal transition through Nodal/Smad2/3 signaling

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World Journal of Stem Cells 2024年第2期16卷 207-227页

作者： Yun Yuan Xu-Fan Zhang Yu-Chen Li Hong-Qing Chen tian Wen Jia-Lian Zheng Zi-Yi Zhao qiong-Ying Hu Department of Laboratory Medicine Hospital of Chengdu University of Traditional Chinese MedicineChengdu 610072Sichuan ProvinceChina Department of Nuclear Medicine Hospital of Chengdu University of Traditional Chinese MedicineChengdu 610072Sichuan ProvinceChina College of Medical Technology Chengdu University of Traditional Chinese MedicineChengdu 611137Sichuan ProvinceChina Department of Hepatology Affiliated Hospital of Liaoning University of Traditional Chinese MedicineShenyang 110032Liaoning ProvinceChina Hospital of Chengdu University of Traditional Chinese Medicine Chengdu 610072Sichuan ProvinceChina Traditional Chinese Medicine Regulating Metabolic Diseases Key Laboratory of Sichuan Province Chengdu 610072Sichuan ProvinceChina

BACKGROUND Colorectal cancer stem cells(CCSCs)are heterogeneous cells that can self-renew and undergo multidirectional differentiation in colorectal cancer(CRC)patients.CCSCs are generally accepted to be important sources of CRC and are responsible for the progression,metastasis,and therapeutic resistance of CRC.Therefore,targeting this specific subpopulation has been recognized as a promising strategy for overcoming CRC.AIM To investigate the effect of VX-509 on CCSCs and elucidate the underlying mechanism.METHODS CCSCs were enriched from CRC cell lines by in conditioned serum-free medium.Western blot,Aldefluor,transwell and tumorigenesis assays were performed to verify the phenotypic characteristics of the CCSCs.The anticancer efficacy of VX-509 was assessed in HCT116 CCSCs and HT29 CCSCs by performing cell viability analysis,colony formation,sphere formation,flow cytometry,and western blotting assessments in vitro and tumor growth,immunohistochemistry and immunofluorescence assessments in vivo.RESULTS Compared with parental cells,sphere cells derived from HCT116 and HT29 cells presented increased expression of stem cell transcription factors and stem cell markers and were more potent at promoting migration and tumori-genesis,demonstrating that the CRC sphere cells displayed CSC features.VX-509 inhibited the tumor malignant biological behavior of CRC-stem-like cells,as indicated by their proliferation,migration and clonality in vitro,and suppressed the tumor of CCSC-derived xenograft tumors in vivo.Besides,VX-509 suppressed the CSC character-istics of CRC-stem-like cells and inhibited the progression of epithelial-mesenchymal transition(EMT)signaling in vitro.Nodal was identified as the regulatory factor of VX-509 on CRC stem-like cells through analyses of differen-tially expressed genes and CSC-related database information.VX-509 markedly downregulated the expression of Nodal and its downstream phosphorylated Smad2/3 to inhibit EMT progression.Moreover,VX-509 reversed the dedifferentiation of CCSCs and inhibit

关键词： Colorectal cancer stem cells Stemness VX-509 Epithelial-mesenchymal transition Nodal

A solubility limited pyrene-4,5,9,10-tetraone-based covalent organic framework for high-performance aqueous zinc-organic batteries

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Nano Research 2024年第6期17卷 5095-5103页

作者： Min Cheng Shibing Zheng tianjiang Sun Diantao Li Weijia Zhang Zhengtai Zha qiong Sun Jing tian Kai Zhang Zhanliang Tao Frontiers Science Center for New Organic Matter State Key Laboratory of Advanced Chemical Power SourcesKey Laboratory of Advanced Energy Materials Chemistry(Ministry of Education)Collaborative Innovation Center of Chemical Science and Engineering(Tianjin)Renewable Energy Conversion and Storage CentreNankai UniversityTianjin 300071China Haihe Laboratory of Sustainable Chemical Transformations Tianjin 300192China

Pyrene-4,5,9,10-tetraone(PTO),with a high theoretical capacity of 408 mAh·g^(−1),is a promising candidate for rechargeable aqueous zinc-ion batteries(RAZIBs),but its zincated products during discharge process suffer from high solubility in electrolytes.Herein,aβ-ketoenamine-linked two-dimensional(2D)covalent organic framework(COF)based on a 2,7-diaminopyrene-4,5,9,10-tetraone(4KT-BD)monomer and a 2,4,6-trihydroxy-benzene-1,3,5-tricarbaldehyde(Tp)node(4KT-Tp-COF)is synthesized to address the above issue.The well-designed 4KT-Tp-COF displays low solubility in 3 M Zn(CF3SO3)2 owing to the favorableπ-πstacking as well as extended structure.Besides,the ingenious structural design of the active molecule and the long-range ordered nano-channels alter the intramolecular electron distribution,which facilitates the ionic diffusion.Consequently,the 4KT-Tp-COF cathode exhibits a stable capacity of 181 mAh·g^(−1)at 0.2 A·g^(−1),superior rate capability of 139 mAh·g^(−1)at 20 A·g^(−1),and a long lifetime of 1000 cycles without capacity loss at 30 A·g^(−1).Even at a low temperature of−20°C,the electrode also performs an ultralong cycling life of 9000 cycles with a capacity of 106 mAh·g^(−1)at 5 A·g^(−1).The comprehensive characterizations of ex-situ analyses together with the theoretical calculations validate that the groups of C=O can contribute highly accessible redox-active sites for Zn^(2+)storage.The ultra-stable 4KT-Tp-COF cathode provides important insights for designing robust organic electrodes for sustainable and large-scale electrochemical energy storage.

关键词： pyrene-4,5,9,10-tetraone solubility limited covalent organic framework zinc batteries

Synergistic anionic/zwitterionic mixed surfactant system with high emulsification efficiency for enhanced oil recovery in low permeability reservoirs

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Petroleum Science 2024年第2期21卷 936-950页

作者： Hai-Rong Wu Rong Tan Shi-Ping Hong qiong Zhou Bang-Yu Liu Jia-Wei Chang tian-Fang Luan Ning Kang Ji-Rui Hou National Key Laboratory of Petroleum Resources and Engineering China University of Petroleum-BeijingBeijing102249China Unconventional Petroleum Research Institute China University of Petroleum-BeijingBeijing102249China Gas Production Plant 5 of PetroChina Changqing Oilfield Company PetroChinaXi©an710000ShaanxiChina College of Petroleum Engineering China University of Petroleum-BeijingBeijing102249China College of Science China University of Petroleum-BeijingBeijing102249China Kazakh-British Technical University Almaty050000Kazakhstan

Emulsification is one of the important mechanisms of surfactant flooding. To improve oil recovery for low permeability reservoirs, a highly efficient emulsification oil flooding system consisting of anionic surfactant sodium alkyl glucosyl hydroxypropyl sulfonate(APGSHS) and zwitterionic surfactant octadecyl betaine(BS-18) is proposed. The performance of APGSHS/BS-18 mixed surfactant system was evaluated in terms of interfacial tension, emulsification capability, emulsion size and distribution, wettability alteration, temperature-resistance and salt-resistance. The emulsification speed was used to evaluate the emulsification ability of surfactant systems, and the results show that mixed surfactant systems can completely emulsify the crude oil into emulsions droplets even under low energy conditions. Meanwhile,the system exhibits good temperature and salt resistance. Finally, the best oil recovery of 25.45% is achieved for low permeability core by the mixed surfactant system with a total concentration of 0.3 wt%while the molar ratio of APGSHS:BS-18 is 4:6. The current study indicates that the anionic/zwitterionic mixed surfactant system can improve the oil flooding efficiency and is potential candidate for application in low permeability reservoirs.

关键词： Anionic/zwitterionic mixed surfactant system Emulsification Synergistic effect Low permeability reservoir Enhanced oil recovery

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水下多针电极微秒脉冲流光放电特性

物理学报 2024年第7期73卷 271-280页

作者：杨双越温小琼杨元天李霄大连理工大学物理学院大连116024

多针电极结构是实现大体积水下放电的基础性电极结构,研究其放电基本特性对其他大体积水下放电电极结构的设计具有重要参考意义.本文构建了一个可安装21根针的多针电极,利用四分幅超高速相机研究了单个脉冲放电过程中可能放电的针电极... 详细信息

多针电极结构是实现大体积水下放电的基础性电极结构,研究其放电基本特性对其他大体积水下放电电极结构的设计具有重要参考意义.本文构建了一个可安装21根针的多针电极,利用四分幅超高速相机研究了单个脉冲放电过程中可能放电的针电极数目以及电极阵列边缘和内侧针电极放电形态的差异;采用COMSOL软件模拟计算了多针电极结构的电场分布,讨论了电场分布对多针电极放电的影响,研究了多针电极结构的放电能量效率.结果发现:在单个脉冲放电过程中,21根针电极不是同时发生放电的,最大放电针电极数目随电压和针针间距的增大而增加.在同一个脉冲放电过程中,位于电极阵列边缘的针电极相比于位于阵列内侧的针电极产生的流光丝较长且偏离针电极轴线的偏角相对较大,这主要是针电极之间电场相互叠加干扰引起的.针针间距越小,针电极之间电场的相互叠加干扰越大,阵列边缘与内侧电极放电形态的差异越大,放电能量效率越低.

关键词：水下流光放电多针电极结构电场分布

Enzyme-like C-H Oxidation of Glucosides Promoted by Visible Light

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CCS Chemistry 2022年第11期4卷 3599-3608页

作者： Mingzhong Wu Qian Jiang qiong tian tianyun Guo Feng Cai Shouchu Tang Jian Liu Xiaolei Wang State Key Laboratory of Applied Organic Chemistry Department of Chemistry and School of PharmacyLanzhou UniversityLanzhou 730000 State Key Laboratory of Veterinary Etiological Biology OIE/National Foot and Mouth Disease Reference LaboratoryLanzhou UniversityLanzhou 730000 The National Glycoengineering Research Center Shandong Provincial Key Laboratory of Carbohydrate Chemistry and GlycobiologyShandong UniversityQingdao 266237

To match nature’s prowess at using enzymes to make desired motifs in a regioselective fashion,we explore the use of visible light for the selective oxidation of the hydroxyl group to afford the corresponding ketosaccharide.This highly admirable approach offers several advantages over the enzymatic approach in terms of yields and the scope of substrates.Herein,we report the development of a simple visiblelight-promoted selective oxidation of unprotected glucosides that allows for inexpensive access to valuable keto-saccharide building blocks.The method is employed on a variety of different natural and artificial glucosides,is operationally simple and scalable,and can be used to access keto-saccharides rapidly and inexpensively.

关键词： keto-saccharide selective oxidation unprotected glucoside visible-light

石粉替代率对聚合物机制砂粘结砂浆性能及微细观结构的影响

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材料导报 2024年第6期38卷 132-138页

作者：田浩正乔宏霞冯琼韩文文兰州理工大学土木工程学院兰州730050 兰州理工大学甘肃省先进土木工程材料工程研究中心兰州730050 兰州理工大学西部土木工程防灾减灾教育部工程研究中心兰州730050

为研究凝灰岩石粉在聚合物粘结砂浆中应用的可行性,分析了石粉部分替代水泥对聚合物粘结砂浆工作性能及力学性能的影响规律,并采用压汞法(MIP)、扫描电子显微镜(SEM)和傅里叶变换红外光谱(FTIR)试验研究砂浆内部孔结构及水化产物微观形... 详细信息

为研究凝灰岩石粉在聚合物粘结砂浆中应用的可行性,分析了石粉部分替代水泥对聚合物粘结砂浆工作性能及力学性能的影响规律,并采用压汞法(MIP)、扫描电子显微镜(SEM)和傅里叶变换红外光谱(FTIR)试验研究砂浆内部孔结构及水化产物微观形貌的变化规律。结果表明:凝灰岩石粉在聚合物粘结砂浆中具有较好的适用性;砂浆强度随石粉替代率的增加呈先增大后减小的趋势,在替代率为15%(质量分数,下同)时,砂浆7 d、28 d抗折强度、抗压强度和粘结强度达到最大值,此时工作性能也较优。当石粉替代率不大于15%时,其对粘结砂浆微细观结构的影响以填充效应和晶核效应为主,可有效改善砂浆内部密实度,且有利于内部孔结构向少害孔和无害孔发展;当石粉替代率为15%时,H_(2)O、OH^(-)、CO_(3)^(2-)等特征振动峰强度最高,即此时内部水化最为充分;当石粉替代率超过15%时,石粉对粘结砂浆工作性能、力学性能和微细观结构均产生不利的影响。

关键词：聚合物粘结砂浆凝灰岩石粉力学性能孔结构微观形貌

现代微生物学研究生课程教学改革与实践——专题教学与seminar教学模式相结合

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微生物学杂志 2024年第1期44卷 123-128页

作者：刘琼蔚晓敏黄孝天南昌大学基础医学院江西南昌330000

现代微生物学是面向基础医学专业硕士研究生开设的一门专业基础课程,旨在培养学生的基本科研素养和科研创造力,而传统的讲授型授课方式已无法满足新时代医学研究生教育要求。因此,本文通过专题教学与seminar教学模式(“讨论课”教学模式... 详细信息

现代微生物学是面向基础医学专业硕士研究生开设的一门专业基础课程,旨在培养学生的基本科研素养和科研创造力,而传统的讲授型授课方式已无法满足新时代医学研究生教育要求。因此,本文通过专题教学与seminar教学模式(“讨论课”教学模式)相结合,设置六大专题板块辅以学生seminar汇报讨论,应用于现代微生物学研究生课程教学,探讨该教学实践的应用效果,全面提升医学研究生的知识理论水平,培养具有创新思维和具备基本科研素质的高层次医学人才,也为医学类专业其他研究生课程的教学改革提供有益参考。

关键词：现代微生物学研究生课程专题教学 seminar教学(“讨论课”教学) 教学实践

存在未知时滞非线性系统的迭代变区间预测迭代学习控制

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控制理论与应用 2024年第4期41卷 701-715页

作者：余琼霞田丰臣孙俊杰侯忠生河南理工大学电气工程与自动化学院河南焦作454000 焦作煤业(集团)有限责任公司铁路运输处河南焦作454000 青岛大学自动化学院山东青岛266071

本文针对机理模型未知的非线性非仿射多入多出(MIMO)离散时间系统,研究了系统同时存在未知时滞和迭代变化运行时间区间的预测迭代学习控制(PILC)问题.首先利用未知时滞的上下界信息建立了一种新型的动态线性化(DL)模型,理论分析表明该... 详细信息

本文针对机理模型未知的非线性非仿射多入多出(MIMO)离散时间系统,研究了系统同时存在未知时滞和迭代变化运行时间区间的预测迭代学习控制(PILC)问题.首先利用未知时滞的上下界信息建立了一种新型的动态线性化(DL)模型,理论分析表明该模型能够等价描述本文所考虑的存在未知时滞的未知非线性系统.同时,设计一种新的数据补偿机制用以处理由于系统运行时间区间迭代变化而引起的数据丢失问题.基于所建立的DL模型和数据补偿机制,设计了能够同时处理未知时滞和迭代变化运行时间区间的预测迭代学习控制方法.通过严格的理论分析同时给出了建模误差和跟踪控制误差的收敛性质.最后,通过仿真进一步验证了所提方法的有效性.

关键词：迭代学习控制预测迭代学习控制未知时滞迭代变区间

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