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Criteria of limiting temperature and parametric analysis of the large deflection behavior for fully restrained steel beams in fire

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Science China(Technological Sciences) 2012年第1期55卷 264-275页

作者： XI Feng luan yanping Shandong Provincial Key Laboratory of Structural Engineering School of Civil Engineering Shandong Jianzhu University Jinan 250101 China School of Civil Engineering Shandong Jianzhu University Jinan 250101 China

This paper mainly involve 3 parts:1) To apply the minimum principle of acceleration in dynamics of elastic-plastic continua at finite deformation to the statics problems,a computing model is presented for the restrained steel beams exposed to the *** this model,both effects of large deflection and thermal expansion deformation are taken into account,and the constitutive equations with the temperature effects are *** a dynamic finite difference(DFD) method is presented by using the dis-crete technique,which can be used in simulating the response of the steel beams at elevated temperature,and the large deflec-tion behavior and catenary action effects of the beams can be adequately *** primary numerical results show that the method is valid and *** with other methods,this technique is very simple,and it can also be further devel-oped to simulate the behavior of steel beams subjected to the coupling loading of explosion and fire when both effects of strain rate and inertia are considered.2) By using this DFD method,detailed parametric analysis are presented so as to check the consistency of response results for several different formulas of thermal expansion deformation and retention factors of steel at elevated temperature,the influence of these parameters on the critical temperature is examined.3) Based on the analysis for the curves of temperature-generalized yield function comprised by the axial force and bending moment,both criteria to determine the limiting temperature(or failure temperature) of large deflection steel beams are presented more explicitly,that is,both lim-iting temperatures can be determined by if the catenary force begins to appear or arrives at the maximum value,*** is shown by numerical results that both limiting temperatures are close to the both critical temperatures which are correspond-ing to the maximum deflections equal to span/20 and span/10,*** conclusion may be helpful to make r

关键词： steel beam fire DFD method large deflection parametric analysis limiting temperature criteria yield function

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Amplified Detection of Iron Ion Based on Plasmon Enhanced Fluorescence and Subsequently Fluorescence Quenching

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Nano-Micro Letters 2014年第4期6卷 327-334页

作者： Lin Zhou Han Zhang yanping luan Si Cheng Li-Juan Fan Jiangsu Key Laboratory of Advanced Functional Polymer Design and Application College of Chemistry Chemical Engineering and Materials Science Soochow University

A facile and rapid approach for detecting low concentration of iron ion(Fe3+) with improved sensitivity was developed on the basis of plasmon enhanced fluorescence and subsequently amplified fluorescence ***1Ag4@Si O2 nanoparticles were synthesized and dispersed into fluorescein isothiocyanate(FITC) solution. The fluorescence of the FITC solution was improved due to plasmon enhanced fluorescence. However, efficient fluorescence quenching of the FITC/Au1Ag4@Si O2 solution was subsequently achieved when Fe3+, with a concentration ranging from17 n M to 3.4 l M, was added into the FITC/Au1Ag4@Si O2 solution, whereas almost no fluorescence quenching was observed for pure FITC solution under the same condition. FITC/Au1Ag4@Si O2 solution shows a better sensitivity for detecting low concentration of Fe3+compared to pure FITC solution. The quantized limit of detection toward Fe3+was improved from 4.6 l M for pure FITC solution to 20 n M for FITC/Au1Ag4@Si O2 solution.

关键词： Gold–silver alloy Plasmon enhanced fluorescence Fluorescence quenching Iron ion

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Melting Evaluation of Phase Change Materials Impregnated into Cascaded Metal Foams with Regionalized Enhancement

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Journal of Thermal Science 2025年第1期34卷 223-241页

作者： WEI Xinyi ZHANG Nan ZHANG Zhaoli CAO Xiaoling YUAN yanping School of Mechanical Engineering Southwest Jiaotong University

Metal foam promotes the heat transfer of phase change materials(PCMs) in the penalty of reducing the energy storage density of the composite *** this work,the effects of constant porosity(0.96,0.94,0.92,or 0.90) and pore density(PPI) of metal foam on heat transfer of composite PCMs are *** rate could be enhanced by employing with low porosity copper ***,aiming to the right bottom phase changing "dead region",a regionalized enhancement strategy of cascaded metal foams is *** dynamic melting performances of all the composite PCMs are comprehensively *** results reveal that the cascaded configuration is beneficial for *** show that the horizontal strategy enhances melting performance:a maximum of 17.98% reduction in total melting time could be reached when the rear part porosity is 90%.The energy storage density rate could be raised by 5.48%.Besides,the vertical strategy performs with a better average temperature uniformity of 0.441 and brings a lower temperature in the heated *** sum up,the regionalized enhancement of copper foam provides better performance in the phase change *** shows significant potential for solar heat storage and thermal protection.

关键词： copper metal foam heat transfer enhancement phase change materials regionalized enhancement

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Two paths, one goal: mechanism of calcium homeostasis to balance plant growth and immunity

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Science China Life Sciences 2025年第1期68卷 306-308页

作者： Aziz Ul Ikram yanping Jing Huan Chen Jian Chen International Genome Center Jiangsu University Joint Center for Single Cell Biology School of Agriculture and BiologyShanghai Jiao Tong University

Calcium(Ca2+) is an essential nutrient and a cellular signal in plants. The level of free Ca2+in the apoplast is ～10,000-fold higher than that in the cytoplasm at the resting state. This large Ca2+level gradient across the membrane between the interior and exterior can cause Ca2+overload and toxicity. Plants have evolved mechanisms to export Ca2+out of the cytoplasm or store it in intracellular organelles, such as endoplasmic reticulum（ER）, mitochondria, and vacuole.

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Intermolecular reductive coupling of aliphatic ketones with alkynes and alkenes by BCN photocatalysts

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Science China Chemistry 2025年第1期68卷 181-185页

作者： yanping Xia Luyang Sun Jiajia Cheng Sibo Wang Meifang Zheng Xinchen Wang State Key Laboratory of Photocatalysis on Energy and Environment College of Chemistry Fuzhou University

A photocatalytic process was developed for intermolecular reductive coupling of aliphatic ketones with alkynes/alkenes to furnish tertiary alcohols. Mechanistic studies support that boron carbonitrides(BCN) promote the single electron reduction of unactivated aliphatic ketones to generate ketyl radicals with visible light irradiation, which then react with alkynes and alkenes to afford the allylic and aliphatic alcohols, respectively. The heterogeneous photocatalytic system is compatible with diverse substrates including pharmaceutical-related molecules(43 examples) with reusability and scale-up experiments, verifying the complementary synthetic utility of this method to the homogeneous catalysts.

关键词： aliphatic ketones ketyl radical intermolecular cross-coupling tertiary alcohols

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Analysis of Two-Grid Methods for Nonlinear Parabolic Equations by Expanded Mixed Finite Element Methods

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Advances in Applied Mathematics and Mechanics 2009年第6期1卷 830-844页

作者： yanping Chen Peng luan Zuliang Lu School of Mathematical Science South China Normal UniversityGuangzhou 510631GuangdongChina Mathematics Teaching and Research Group Sanshui Experimental High School of Zhongshan UniversityFoshan 528145GuangdongChina Hunan Key Lab for Computation and Simulation in Science and Engineering Department of MathematicsXiangtan UniversityXiangtan 411105HunanChina

In this paper,we present an efficient method of two-grid scheme for the approximation of two-dimensional nonlinear parabolic equations using an expanded mixed finite element *** use two Newton iterations on the fine grid in our ***,we solve an original nonlinear problem on the coarse nonlinear grid,then we use Newton iterations on the fine grid *** two-grid idea is from Xu's work[SIAM ***.,33(1996),pp.1759–1777]on standard finite *** also obtain the error estimates for the algorithms of the two-grid *** is shown that the algorithm achieve asymptotically optimal approximation rate with the two-grid methods as long as the mesh sizes satisfy h=O(H^((4k+1)/(k+1))).

关键词： Nonlinear parabolic equations two-grid scheme expanded mixed finite element methods Gronwall’s Lemma

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益生菌和小檗碱对肠道菌群失调诱导糖尿病预防的研究

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中华灾害救援医学 2019年第7期7卷 414-418页

作者：栾艳平苏峰倪军张静何嘉骐乔泽渊新乡医学院研究生院 453003 陆军第八十三集团军医院肾病内分泌科新乡453003

糖尿病是一组以慢性高血糖为特征的代谢性疾病。肠道菌群是一个复杂的微生物群落,存在于胃肠道生态系统中,其变化不仅影响各种肠道疾病,而且影响糖尿病。许多研究表明,糖尿病患者肠道菌群的组成发生了变化。益生菌和小檗碱可通过改变肠... 详细信息

糖尿病是一组以慢性高血糖为特征的代谢性疾病。肠道菌群是一个复杂的微生物群落,存在于胃肠道生态系统中,其变化不仅影响各种肠道疾病,而且影响糖尿病。许多研究表明,糖尿病患者肠道菌群的组成发生了变化。益生菌和小檗碱可通过改变肠道菌群及其代谢产物,减轻低水平慢性炎性反应、改善短链脂肪酸和胆汁酸的代谢,成为预防和改善糖尿病的常用药物。笔者概述了益生菌和小檗碱对肠道菌群的影响和改善糖尿病的研究进展,为今后糖尿病的相关研究提供理论依据和思路。

关键词：益生菌小檗碱糖尿病肠道菌群

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Developing controllable hypermutable Clostridium cells through manipulating its methyl-directed mismatch repair system

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Protein & Cell 2013年第11期4卷 854-862页

作者： Guodong luan Zhen Cai Fuyu Gong Hongjun Dong Zhao Lin yanping Zhang Yin Li CAS Key Laboratory of Microbial Physiological and Metabolic Engineering Institute of MicrobiologyChinese Academy of SciencesBeijing 100101China University of Chinese Academy of Sciences Beijing 100049China

Development of controllable hypermutable cells can greatly benefit understanding and harnessing microbial ***,there have not been any similar sys-tems developed for Clostridium,an important bacterial *** we report a novel two-step strategy for de-veloping controllable hypermutable cells of Clostridium acetobutylicum,an important and representative indus-trial ***,the mutS/L operon essential for methyl-directed mismatch repair(MMR)activity was inactivated from the genome of *** to generate hy-permutable cells with over 250-fold increased mutation ***,a proofreading control system carrying an inducibly expressed mutS/L operon was *** hypermutable cells and the proofreading control system were integrated to form a controllable hypermut-able system SMBMutC,of which the mutation rates can be regulated by the concentration of anhydrotetracycline(aTc).Duplication of the miniPthl-tetR module of the proof-reading control system further signifi cantly expanded the regulatory space of the mutation rates,demonstrating hypermutable Clostridium cells with controllable mutation rates are *** developed *** strain SMBMutC2 showed higher survival capacities than the control strain facing butanol-stress,indicating greatly increased evolvability and adaptability of the controllable hypermutable cells under environmental challenges.

关键词： Clostridium acetobutylicum mutation rates hypermutable cells artifi cial control

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基于电路理论的岷江流域生态安全格局构建研究

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水土保持研究 2025年第2期32卷 263-275页

作者：杨艳萍干晓宇吴潇四川大学建筑与环境学院成都610065

[目的]精准提取各生态空间要素,构建生态安全格局,维持流域生态系统的健康稳定及生态环境保护的可持续发展。[方法]以岷江流域为研究区,评估其生态系统服务重要性以筛选生态源地,通过地质灾害敏感性评价修正土地利用基本阻力面,并基于... 详细信息

[目的]精准提取各生态空间要素,构建生态安全格局,维持流域生态系统的健康稳定及生态环境保护的可持续发展。[方法]以岷江流域为研究区,评估其生态系统服务重要性以筛选生态源地,通过地质灾害敏感性评价修正土地利用基本阻力面,并基于电路理论,量化识别廊道、夹点、障碍点等生态空间要素,构建生态安全格局。[结果](1)面积阈值设定为7 km^(2)时,筛选出生态源地77个,面积占比为30.77%,关键生态源地主要在“龙门—邛崃山脉”及其以北的岷山中南段雪宝顶等林地区,以及岷江中下游的部分耕地和林地。(2)生态廊道共176条,总长度2 072.96 km,关键生态廊道总长度占比为21.32%,集中在岷江中游;生态夹点共719处,总面积1 578.5 km^(2);生态障碍点163处,总面积2 410 km^(2)。(3)构建“四区两带一廊”的岷江流域生态安全格局,并以岷江乡为例,探索了岷江流域“全流域—局域单元”生态空间协同修复路径。[结论]生态修复时要考虑多尺度格局的衔接与融合,实行系统性、差异化的生态空间分区治理,提升生态景观连通性及生境质量,促进物质流通。

关键词：生态安全格局生态修复电路理论生态系统服务地质灾害敏感性岷江流域

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长城国家文化公园建设中传统村落嵌入路径研究

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中国非物质文化遗产 2025年第1期 115-122页

作者：李彦平中国艺术研究院(中国非物质文化遗产保护中心)

关系性嵌入、结构性嵌入、时间性嵌入是格兰诺维特在嵌入理论中提出的三种嵌入类型。嵌入理论在社会学、人类学、政治学、历史学等学科中被广泛引入和探究。长城沿线的传统村落与长城遗产在长期的共存共荣共发展中,形成了嵌入式发展的... 详细信息

关系性嵌入、结构性嵌入、时间性嵌入是格兰诺维特在嵌入理论中提出的三种嵌入类型。嵌入理论在社会学、人类学、政治学、历史学等学科中被广泛引入和探究。长城沿线的传统村落与长城遗产在长期的共存共荣共发展中,形成了嵌入式发展的关系。在长城国家文化公园建设中,传统村落可以从整体性保护理念、活态遗产特色要素、主题功能区域建设、多维度阐释体系等方面构建嵌入路径。基于这一理念下的实践提炼了与长城相关的物质文化遗产和非物质文化遗产要素,不仅有利于传统村落的保护和发展,也有利于国家文化公园的建设和推进,以及长城文化的传承和弘扬。

关键词：长城国家文化公园非物质文化遗产传统村落嵌入理论路径

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