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Triple points and phase transitions of D-dimensional dyonic Ad S black holes with quasitopological electromagnetism in Einstein–Gauss–Bonnet gravity

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Chinese Physics B 2024年第6期33卷 272-287页

作者：牟平辉蒋青权何柯腱李国平 School of Physics and Astronomy China West Normal UniversityNanchong 637000China College of Physics Chongqing UniversityChongqing 401331China

By considering the negative cosmological constant Λ as a thermodynamic pressure, we study the thermodynamics and phase transitions of the D-dimensional dyonic Ad S black holes(BHs) with quasitopological electromagnetism in Einstein–Gauss–Bonnet(EGB) gravity. The results indicate that the small/large BH phase transition that is similar to the van der Waals(vdW) liquid/gas phase transition always exists for any spacetime dimensions. Interestingly, we then find that this BH system exhibits a more complex phase structure in 6-dimensional case that is missed in other ***, it shows for D = 6 that we observed the small/intermediate/large BH phase transitions in a specific parameter region with the triple point naturally appeared. Moreover, when the magnetic charge turned off, we still observed the small/intermediate/large BH phase transitions and triple point only in 6-dimensional spacetime, which is consistent with the previous results. However, for the dyonic Ad S BHs with quasitopological electromagnetism in Einstein–Born–Infeld(EBI) gravity, the novel phase structure composed of two separate coexistence curves observed by Li et al. [Phys. Rev. D105 104048(2022)] disappeared in EGB gravity. This implies that this novel phase structure is closely related to gravity theories, and seems to have nothing to do with the effect of quasitopological electromagnetism. In addition, it is also true that the critical exponents calculated near the critical points possess identical values as mean field theory. Finally, we conclude that these findings shall provide some deep insights into the intriguing thermodynamic properties of the dyonic Ad S BHs with quasitopological electromagnetism in EGB gravity.

关键词： AdS black hole phase transition triple point

Sharp Threshold of Global Existence for the Klein-Gordon Equations with Critical Nonlinearity

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Acta Mathematicae Applicatae Sinica 2009年第2期25卷 273-282页

作者： Zai-hui Gan Bo-ling Guo jian Zhang College of Mathematics and Software Science Sichuan Normal University Chengdu 610068 China Institute of Applied Physics and Computational Mathematics PO Box 8009 Beijing 100088 China

In this paper, we present a cross-constrained variational method to study the Cauchy problem of the nonlinear Klein-Gordon equations with critical nonlinearity in two space dimensions. By constructing a type of cross-constrained variational problem and establishing so-called cross-invariant manifolds of the evolution flow, we establish a sharp threshold of global existence and blowup of it. Furthermore, we answer the question： How small are the initial data if the solution exists globally.

关键词： Sharp threshold Klein-Gordon equation cross-constrained variational problem global existence blowup

通过添加微量Mn元素激活非基面滑移提高镁合金塑性

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Transactions of Nonferrous Metals Society of China 2024年第2期34卷 504-518页

作者：周世博刘婷婷汤爱涛时慧敬学锐彭鹏章建跃潘复生重庆大学材料科学与工程学院重庆400044 Institute of Metallic Biomaterials Helmholtz-Zentrum HereonMax-Planck-Straße 1D-21502GeesthachtGermany 西南大学材料与能源学院重庆400715 重庆大学镁合金国家工程研究中心重庆400044 重庆科技学院冶金和材料工程学院重庆401331 Department of Materials Science and Engineering The Ohio State UniversityColumbusOH 43210USA

分析微量锰添加对镁合金显微组织和力学性能的影响。采用电子背散射技术、迹线分析、透射电镜和粘塑性自洽模拟等方法研究变形过程中的塑性变形机理。结果表明:Mn的加入使Mg−Mn合金的平均晶粒尺寸由28.30μm减小到5.10μm;同时,随着Mn... 详细信息

分析微量锰添加对镁合金显微组织和力学性能的影响。采用电子背散射技术、迹线分析、透射电镜和粘塑性自洽模拟等方法研究变形过程中的塑性变形机理。结果表明:Mn的加入使Mg−Mn合金的平均晶粒尺寸由28.30μm减小到5.10μm;同时,随着Mn含量的增加,样品的断裂伸长率由14.33%提高到20.33%,屈服强度则由84 MPa提高到180 MPa。这种同时提高塑性和强度的原因是基面滑移和非基面滑移之间的临界剪切应力差从173 MPa减小到115 MPa,导致非基面滑移活动明显增加。通过微合金元素调整滑移系统差异为开发具有高强度和延展性的镁合金提供了一种途径。

关键词：镁合金显微组织演变力学性能塑性变形机理

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木质素应用及其球形颗粒特性研究进展

中国造纸 2024年第3期43卷 65-72页

作者：董文泽岳景华黄河交通学院河南焦作454950

木质素作为一种可广泛获得的生物质资源,在高附加值化学品、纳米材料和生物质基材料中具有巨大的应用潜力。作为地球上含量丰富的天然高分子,木质素虽然在传统的制浆造纸业中属于副产物,但其在环保、可持续性及生物可降解产品的开发中... 详细信息

木质素作为一种可广泛获得的生物质资源,在高附加值化学品、纳米材料和生物质基材料中具有巨大的应用潜力。作为地球上含量丰富的天然高分子,木质素虽然在传统的制浆造纸业中属于副产物,但其在环保、可持续性及生物可降解产品的开发中显示出巨大的潜力。本文主要对木质素的化学结构、表征与分离方法,及其在不同工业领域的应用(如分散剂、黏合剂、涂料和复合材料)尤其是球形木质素的应用等方面进行综述,并对未来木质素相关研究方向进行了展望。

关键词：木质素球形颗粒生物质基材料应用

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新时代实现人民美好生活需要的协同机制

中南民族大学学报（人文社会科学版） 2024年第2期44卷 144-150,187页

作者：王姝越黄浩武汉理工大学马克思主义学院湖北武汉430062 华南农业大学马克思主义学院广东广州510642

实现人民美好生活需要是中国共产党治国理政的重要目标。就当前目标而言,实现人民美好生活需要从根本上倚赖于个人和社会、社会和政府之间的良性互动关系,需要从理论上构建科学、合理的协同机制。美好生活需要实现的协同机制建构,起点... 详细信息

实现人民美好生活需要是中国共产党治国理政的重要目标。就当前目标而言,实现人民美好生活需要从根本上倚赖于个人和社会、社会和政府之间的良性互动关系,需要从理论上构建科学、合理的协同机制。美好生活需要实现的协同机制建构,起点是建立理性的美好生活愿景,关键是建立多元一体、分工配合的主体系统,归宿是在实践中形成政府、社会和个人的行动合力。

关键词：美好生活需要人民中心协同机制

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面向实时位置的隐私保护优化与加速求解算法

计算机研究与发展 2024年第9期61卷 2156-2169页

作者：董恺王立夫凌振东南大学计算机科学与工程学院南京211189

现有的电动汽车API平台(如SmartCar)使用访问控制机制来保护用户的隐私.为了在启用不可信位置服务功能的同时保护位置隐私,位置隐私保护机制(LPPM)根据用户的真实位置生成一个随机的伪位置作为报告位置.现有技术通过在离散网格上解决一... 详细信息

现有的电动汽车API平台(如SmartCar)使用访问控制机制来保护用户的隐私.为了在启用不可信位置服务功能的同时保护位置隐私,位置隐私保护机制(LPPM)根据用户的真实位置生成一个随机的伪位置作为报告位置.现有技术通过在离散网格上解决一个最优化问题构建一个最佳的LPPM,该最佳LPPM实现了在最低可容忍效用限制下的最高隐私,反之亦然.然而,它们很难直接应用于电动汽车等实时场景,因为生成最佳LPPM所需的运行时间太长(可能需要数天).另一个问题涉及构建出的LPPMs的最佳性.揭示了一些意外情况(异常),即在粒度更高的细网格上构建的最佳LPPM效用比在粒度较低的粗网格上差.引入了粒度独立性作为有效解决方法,提出了一个名为Divide-and-Coin的最佳LPPM,其可以实时执行.Divide-and-Coin将生成最佳报告位置的运行时间从至少O(n^(2.055))缩短到O(log n),其中n是报告位置的数量.实验结果显示,Divide-and-Coin可以在1s内从城市级区域生成建筑级别的最佳报告位置.

关键词：位置隐私最佳位置隐私保护机制实时位置API 隐私-效用异常粒度独立性

Stability of the Standing Waves for a Class of Coupled Nonlinear Klein-Gordon Equations

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Acta Mathematicae Applicatae Sinica 2010年第3期26卷 427-442页

作者： jian Zhang Zai-hui Gan Bo-ling Guo College of Mathematics and Software Science Sichuan Normal University Chengdu 610066 China Institute of Applied Physics and Computational Mathematics Beijing 100088 China

This paper deals with the standing waves for a class of coupled nonlinear Klein-Gordon equations with space dimension N ≥ 3, 0 〈 p, q 〈 2/N-2 and p ＋ q 〈 4/N. By using the variational calculus and scaling argument, we establish the existence of standing waves with ground state, discuss the behavior of standing waves as a function of the frequency ω and give the sufficient conditions of the stability of the standing waves with the least energy for the equations under study.

关键词： Coupled nonlinear Klein-Gordon equations Stability Standing wave Variational calculus

Analysis of the Effects of Different Synthesis and Processing Methods on Circular RNA Integrity,Protein Expression,and Removal of Immunogenic Impurities

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Journal of Clinical and Nursing Research 2024年第9期8卷 191-200页

作者： Shao Wang Tzuen Yih Saw Zebin Hong Kuo Chieh Liao Haiwei Song yue Wan Genome Institute of Singapore Agency for ScienceTechnology and Research138672 SingaporeSingapore Department of Biochemistry and Molecular Biology University of British ColumbiaVancouverBC V6T 1Z3Canada Institute of Molecular and Cell Biology Agency for ScienceTechnology and Research138673 SingaporeSingapore

Circular RNAs(circRNAs)are emerging as a promising alternative to messenger RNAs(mRNAs)in gene delivery applications due to their enhanced stability and *** circRNA-based therapeutic platforms requires efficient manufacturing of circRNA with broad ***,the permuted intron-exon(PIE)-based circRNA production commonly used to date involves complex RNA synthesis,circularization,precursor RNA digestion,and impurity removal steps that have limited practical *** co-transcriptional circularization could effectively streamline circRNA production,and both cellulose/phosphatase treatment and high-performance liquid chromatography(HPLC)have demonstrated their reliability in mRNA manufacturing,their potential effects on the quality,translation,and reactogenicity of circRNA remained to be fully ***,using circRNAs systematically manufactured through three independent workflows,we comprehensively examined the utilities of these RNA synthesis and processing methods in circRNA production by comparing the integrity,translation,and immunogenicity of their circRNA *** began by manufacturing a mNeonGreen(mNG)-encoding circRNA through these workflows and subsequently assessed circRNA integrity via E-gel EX *** expression was then monitored in HEK 293T,A549,and DC2.4 cells at 72 hours ***,we evaluated the immunogenicity of these circRNAs by measuring their interferon beta(IFN-β)induction in A549 cells at 4 hours *** HPLC purification over cellulose and phosphatase treatment resulted in 10-14%higher circRNA enrichment by reducing nicking associated with processing *** expression remained consistent across circRNAs from different workflows(P>0.05),demonstrating that co-transcriptional circularization produces circRNA with translation levels comparable to those obtained from the conventional PIE ***,both cellulose/phosphatase treatment

关键词： Nucleic acid therapeutics RNA manufacturing Circular RNA Gene delivery

芳香多酸镧配合物的制备及其改性PA66的抗黄变性与力学性能的研究

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稀土 2024年第1期45卷 120-131页

作者：辛跃廖利民贾奕帆龚剑兵朱新生苏州大学非织造材料工程系江苏苏州215021 江苏文凤化纤集团江苏海安226600 南通纺织丝绸产业技术研究院江苏南通226300

黄变不仅改变了聚酰胺(尼龙)的外观与微观结构,而且也缩短了其使用寿命,研究聚酰胺抗热氧老化及抗黄变性能有着重要意义。利用溶液法、低温固相法与超声波合成法合成了芳香多酸镧,探讨了芳香多酸镧对PA66的热氧化稳定性、力学性能与阻... 详细信息

黄变不仅改变了聚酰胺(尼龙)的外观与微观结构,而且也缩短了其使用寿命,研究聚酰胺抗热氧老化及抗黄变性能有着重要意义。利用溶液法、低温固相法与超声波合成法合成了芳香多酸镧,探讨了芳香多酸镧对PA66的热氧化稳定性、力学性能与阻燃性能的影响。采用红外光谱、扫描电镜、X射线衍射与热重法等对芳香多酸镧的形貌和微观结构与性能进行了表征。结果表明,混合芳香多酸镧配合物(均苯四甲酸和偏苯三甲酸摩尔比1∶1,溶液法,简称PT11)是一种球状或者棒状、带有微孔的结晶性化合物,其最大热分解温度超过500℃,可充当聚酰胺补强与热氧化稳定剂。PT11推迟PA66热降解过程。PT11P(P表示超声波法)改性PA66黄变指数为31.9%,而纯PA66为45.6%,提高了PA66抗黄变效果,并改善了PA66纤维的拉伸性能。与纯PA66纤维相比,PT11改性PA66纤维的总燃烧热与最大热释放速率分别下降了22.6%和18.6%,其阻燃效果明显。

关键词：芳香多酸镧锦纶热氧化稳定性阻燃抗黄变性能力学性能