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Fluid Dynamics & Materials Processing 2022年第6期18卷 1699-1709页

作者： xufeng li Yantao Bi Shengli Petroleum Engineering Co. Ltd.of SinopecDongying257100China Key Laboratory of Ultra-Deep Well Drilling Engineering Technology of Sinopec Dongying257100China Key Laboratory of Unconventional Drilling and Completion Technology of China Petroleum and Chemical Corporation Dongying257100China

Using the conservation equations for mass,momentum and energy,a model is elaborated to describe the dynamics of high-energy gases in composite-perforation technological processes.The model includes a precise representation of the gunpowder combustion and related killing fluid displacement.Through numerical solution of such equations,the pressure distribution of the high-energy gas in fractures is obtained,and used to determine crack propagation.The accuracy of the model is verified by comparing the simulation results with actual measurements.

关键词： Composite perforation gunpowder burning pressure distribution downhole pressure

Fast and flexible stack‐based inverse tone mapping

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CAAI Transactions on Intelligence Technology 2023年第4期8卷 1444-1454页

作者： Ning Zhang Yuyao Ye Yang Zhao xufeng li Ronggang Wang School of Electronic and Computer Engineering Peking University Shenzhen Graduate SchoolShenzhenChina School of Computer and Information Hefei University of TechnologyHefeiChina Department of Computer Science(CS) College of Engineering(EG)City University of Hong KongHong KongChina

Inverse tone mapping technique is widely used to restore the lost textures from a single low dynamic range image.Recently,many stack‐based deep inverse tone mapping networks have achieved impressive results by estimating a set of multi‐exposure images from a single low dynamic range input.However,there are still some limitations.On the one hand,these methods usually set a fixed length for the estimated multi‐exposure stack,which may introduce computational redundancy or cause inaccurate results.On the other hand,they neglect that the difficulties of estimating each exposure value are different and use the identical model to increase or decrease exposure value.To solve these problems,the authors design an exposure decision network to adaptively determine the number of times the exposure of low dynamic range input should be increased or decreased.Meanwhile,the authors decouple the increasing/decreasing process into two sub‐modules,exposure adjustment and optional detail recovery,based on the characteristics of different variations of exposure values.With these improvements,this method can fast and flexibly estimate the multi‐exposure stack from a single low dynamic range image.Experiments on several datasets demonstrate the advantages of the proposed method compared to state‐of‐the‐art inverse tone mapping methods.

关键词： 2‐D image enhancement image processing

Oriented magnetic liquid metal-filled interlocked bilayer films as multifunctional smart electromagnetic devices

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Nano Research 2023年第1期16卷 1764-1772页

作者： Jinjin li Yue Zhang xufeng li Chunyan Chen Haihan Zou Peng Yi Xiaofang liu Ronghai Yu School of Materials Science and Engineering Beihang UniversityBeijing 100191China

Smart electromagnetic functional devices prepared based on electromagnetic wave responsive materials will provide more convenience for human life in the future.Here,we prepare oriented magnetic liquid metal droplet-filled polydimethylsiloxane films with micropillar array patterned surfaces,and further assemble them into bilayer films with interlocked structures.Once compressed,the increase in conductivity of the film due to the tunneling effect between microarrays and the elongation of liquid metal droplets leads to a rapid increase in electromagnetic interference shielding performance.Accordingly,a tunable electromagnetic interference shielding material with high sensitivity and wide control range is obtained,which has potential applications in electromagnetic wave control systems and intelligent electromagnetic protection systems.Meanwhile,we assemble a strain sensor and a magnetic sensor,which can precisely sense pressure and magnetic field according to changes in electromagnetic signal and electrical signal,respectively.

关键词： magnetic liquid metal electromagnetic interference shielding interlocked structure electromagnetic sensing magnetic sensing

以多元分类、质量贡献为评价导向构建高校教师队伍建设新格局

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中国考试 2024年第1期 12-14,1页

作者：李旭锋西南大学

习近平总书记指出,强教必先强师。培养造就一支师德高尚、业务精湛、结构合理、充满活力的高素质专业化教师队伍,科学精准的教师评价是关键。近年来,西南大学以多元分类、质量贡献为评价导向,在教师队伍“引育用留”体系建设方面进行积... 详细信息

习近平总书记指出,强教必先强师。培养造就一支师德高尚、业务精湛、结构合理、充满活力的高素质专业化教师队伍,科学精准的教师评价是关键。近年来,西南大学以多元分类、质量贡献为评价导向,在教师队伍“引育用留”体系建设方面进行积极探索,取得初步成效。

关键词：业务精湛教师评价评价导向多元分类高校教师队伍建设教师队伍新格局培养造就

基于盒维数与锚杆无损检测技术的杆体应力波特性研究

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煤炭工程 2024年第3期56卷 130-135页

作者：李旭锋赵毅山西焦煤山煤国际凌志达煤业公司山西长治046000 太原理工大学矿业工程学院山西太原030000

为了研究复杂岩层中剪切力与轴向载荷对反射信号特性的影响,将分形维数中的盒维数与应力波特性参数应用到锚杆无损检测之中。通过在锚杆自由端中间加载不同大小的集中载荷,分析了同一试件上加载不同的动态载荷力与不同试件加载不同剪切... 详细信息

为了研究复杂岩层中剪切力与轴向载荷对反射信号特性的影响,将分形维数中的盒维数与应力波特性参数应用到锚杆无损检测之中。通过在锚杆自由端中间加载不同大小的集中载荷,分析了同一试件上加载不同的动态载荷力与不同试件加载不同剪切力对应力波特性的影响。使用MATLAB软件对检测信号进行盒维数计算,研究在不同情况下的盒维数变化规律;对检测信号幅值、有效值、标准差、幅频进行分析,判断其信号强度及其规律。研究结果表明:随着锚固结构轴向载荷与锚杆自由端剪力的逐渐增加,信号强度逐渐减弱;剪切力大小影响锚杆的极限承载能力,随着剪切力的逐渐增大,盒维数会不断增加,锚固结构的极限承载能力也会增加;随着轴向载荷的不断增大,盒维数先增大后减小,在盒维数最大值处锚固结构失效。

关键词：锚杆无损检测剪切力轴向载荷盒维数应力波特性

Rapid formation of Csp^(3)–Csp^(3) bonds through copper-catalyzed decarboxylative Csp^(3)–H functionalization

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Chinese Chemical Letters 2023年第1期34卷 326-332页

作者： Wenwen Cui Yu li xufeng li Junxin li Xiuyan Song Jian Lv Yuan-Ye Jiang Daoshan Yang Key Laboratory of Optic-Electric Sensing and Analytical Chemistry for life Science MOECollege of Chemistry and Molecular EngineeringQingdao University of Science and TechnologyQingdao 266042China School of Chemistry and Chemical Engineering Qufu Normal UniversityQufu 273165China Zhejiang Wansheng Co. Ltd.Linhai 317000China Key Laboratory of Bioorganic Phosphorus Chemistry and Chemical Biology(Ministry of Education) Department of ChemistryTsinghua UniversityBeijing 100084China

Transition-metal-catalyzed decarboxylative and C–H functionalization strategy for the construction of Csp^(2)-Csp^(2),Csp^(2)-Csp,and Csp^(2)-Csp^(3) bonds has been extensively studied.However,research surveys of this synthetic strategy for the Csp^(3)-Csp^(3) bond forming reactions are surprisingly scarce.Herein,we present an efficient approach for the rapid formation of Csp^(3)–Csp^(3) bond through copper-catalyzed decarboxylative Csp^(3)–H functionalization.The present method should provide a useful access to C3-substituted indole scaffolds with possible biological activities.Mechanistic experiments and DFT calculations supported a dual-Cu(Ⅱ)-catalytic cycle involving rate-determining decarboxylation in an outer-sphere radical pathway and spin-crossover-promoted C–C bond formation.This strategy offers a promising synthesis method for the construction of Csp^(3)–Csp^(3) bond in the field of synthetic and pharmaceutical chemistry and extends the number of still limited copper-catalyzed decarboxylative Csp^(3)–Csp^(3) bond forming reaction.

关键词： Copper Cross-coupling Csp^(3)-H functionaliztion Decarboxylation Csp^(3)–Csp^(3)bond formation

An electron donor-acceptor photoactivation strategy for the synthesis of S-aryl dithiocarbamates using thianthrenium salts under mild aqueous micellar conditions

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Chinese Chemical Letters 2023年第11期34卷 124-130页

作者： Hao Xu xufeng li Jie Ma Junze Zuo Xiuyan Song Jian Lv Daoshan Yang Key Laboratory of Optic-electric Sensing and Analytical Chemistry for life Science MOECollege of Chemistry and Molecular EngineeringQingdao University of Science and TechnologyQingdao 266042China Zhejiang Wansheng Co. Ltd.Linhai 317000China Key Laboratory of Bioorganic Phosphorus Chemistry and Chemical Biology(Ministry of Education) Department of ChemistryTsinghua UniversityBeijing 100084China

An eco-friendly and convenient method is developed herein for the synthesis of S-aryl dithiocarbamates via visible-light-induced SET process of an EDA complex between thianthrenium salt functionalized arenes and dithiocarbamate anions under mild aqueous micellar conditions.This strategy indirectly realizes the method for constructing S-aryl dithiocarbamates through site-selective C−H functionalization of arenes.Most importantly,the reaction proceeded smoothly without addition of any photocatalyst,and the by-product thianthrene is recycled in quantity,ultimately minimizing the production of chemical waste.This protocol provides a promising synthesis candidate for the construction of valuable S-aryl dithiocarbamates,which also opens up a new avenue for micellar photocatalysis.

关键词： S-Aryl dithiocarbamates Visible-light EDA complex Thianthrenium salts Micellar photocatalysis

Arabidopsis C3HC4-RING finger E3 ubiquitin ligase At AIRP4 positively regulates stress-responsive abscisic acid signaling

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Journal of Integrative Plant Biology 2016年第1期58卷 67-80页

作者： liang Yang Qiaohong liu Zhibin liu Hao Yang Jianmei Wang xufeng li Yi Yang Key Laboratory of Bio-Resources and Eco-Environment of Ministry of Education College of Life Sciences Sichuan University The Crop Research Institute Sichuan Academy of Agricultural Sciences

Degradation of proteins via the ubiquitin system is an important step in many stress signaling pathways in plants.E3 ligases recognize ligand proteins and dictate the high specificity of protein degradation, and thus, play a pivotal role in ubiquitination. Here, we identified a gene, named Arabidopsis thaliana abscisic acid（ABA）-insensitive RING protein 4（At AIRP4）, which is induced by ABA and other stress treatments. At AIRP4 encodes a cellular protein with a C3HC4-RING finger domain in its C-terminal side, which has in vitro E3 ligase activity. Loss of At AIRP4 leads to a decrease in sensitivity of root elongation and stomatal closure to ABA, whereas overexpression of this gene in the T-DNA insertion mutant atairp4 effectively recovered the ABA-associated phenotypes. At AIRP4 overexpression plants were hypersensitive to salt and osmotic stresses during seed germination, and showed drought avoidance compared with the wild-type and atairp4 mutant plants. In addition, the expression levels of ABA- and droughtinduced marker genes in At AIRP4 overexpression plants were markedly higher than those in the wild-type and atairp4 mutant plants. Hence, these results indicate that At AIRP4 may act as a positive regulator of ABA-mediated drought avoidance and a negative regulator of salt tolerance in Arabidopsis.

关键词： AtAIRP4 abscisic acid drought stress E3 Iigase salt stress

Abscisic acid receptors maintain abscisic acid homeostasis by modulating UGT71C5 glycosylation activity

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Journal of Integrative Plant Biology 2021年第3期63卷 543-552页

作者： Yanlin Ma Jing Cao Qiaoqiao Chen Jiahan He Zhibin liu Jianmei Wang xufeng li Yi Yang Key Laboratory of Bio-Resources and Eco-Environment of Ministry of Education College of Life SciencesSichuan UniversityChengdu 610065China

Uridine diphosphate-glucosyltransferases(UGTs)maintain abscisic acid(ABA)homeostasis in Arabidopsis thaliana by converting ABA to abscisic acid-glucose ester(ABA-GE).UGT71C5 plays an important role in the generation of ABA-GE.Abscisic acid receptors are crucial upstream components of the ABA signaling pathway,but how UGTs and ABA receptors function together to modulate ABA levels is unknown.Here,we demonstrated that the ABA receptors RCAR12/13 and UGT71 C5 maintain ABA homeostasis in Arabidopsis following rehydration under drought stress.Biochemical analyses show that UGT71C5 directly interacted with RCAR8/12/13 in yeast cells,and the interactions between UGT-71C5 and RCAR12/13 were enhanced by ABA treatment.Enzyme activity analysis showed that ABA-GE contents were significantly elevated in the presence of RCAR12 or RCAR13,suggesting that these ABA receptors enhance the activity of UGT71C5.Determination of the content of ABA and ABA-GE in Arabidopsis following rehydration under drought stress revealed that ABA-GE contents were significantly higher in Arabidopsis plants overexpressing RCAR12 and RCAR13 than in nontransformed plants and plants overexpressing RCAR11 following rehydration under drought stress.These observations suggest that RCAR12 and RCAR13 enhance the activity of UGT71C5 to glycosylate excess ABA into ABA-GE following rehydration under drought stress,representing a rapid mechanism for regulating plant growth and development.

关键词： ABA glucosyl ester ABA receptors glycosylation activity ABA homoeostasis kinetic analysis

基于巢隐蔽度影响繁殖成功的巢树选择:以湖南浏阳大围山红嘴相思鸟为例

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生态学杂志 2024年第5期43卷 1354-1359页

作者：杨君林李旭丰周琳李继承张志强李家湘中南林业科技大学野生动植物保护研究所/林学院长沙410004 湖南大围山自然保护区管理所湖南浏阳410309

鸟类选择适宜的巢树营巢是重要的巢址微生境选择策略,巢树提供高隐蔽度的巢址对于增加繁殖成功具有重要意义。为探究红嘴相思鸟(Leiothrix lutea)巢树选择偏好及其对繁殖成功的影响,2019—2021年在湖南浏阳大围山自然保护区对其185个鸟... 详细信息

鸟类选择适宜的巢树营巢是重要的巢址微生境选择策略,巢树提供高隐蔽度的巢址对于增加繁殖成功具有重要意义。为探究红嘴相思鸟(Leiothrix lutea)巢树选择偏好及其对繁殖成功的影响,2019—2021年在湖南浏阳大围山自然保护区对其185个鸟巢的巢树特性、巢位特征及繁殖结果进行了调查,分析了红嘴相思鸟巢树选择偏好、巢位隐蔽度和繁殖成功之间的相关关系。结果表明:(1)红嘴相思鸟对巢树生活型及物种的选择上表现出显著偏好,尤以湖南玉山竹(Yushania farinosa)、华空木(Stephanandra chinensis)、白檀(Symplocos paniculata)等灌木和小径竹树种的选择频率最高。(2)红嘴相思鸟对不同方位的巢位隐蔽度需求不同,更倾向于选择巢上隐蔽度(Mean=63.14%±1.65%)和巢周隐蔽度(Mean=51.89%±1.53%)较高的巢位。(3)鸟巢的综合隐蔽度指数均值为45.23%±1.65%,与繁殖成功率呈显著正相关。本研究中,“巢隐蔽”假说能较好地解释红嘴相思鸟巢树选择偏好,结果可为区域性红嘴相思鸟繁殖栖息地的保护与修复工作提供科学参考。

关键词：鸟类巢址微生境巢树选择策略