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Preparation and Performance of Ternary Early Strength Agent and Quercetin Composite Cement Sealing Material

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Journal of Wuhan University of Technology(Materials Science) 2025年第1期40卷 130-140页

作者： LIU Jian CHEN Meiting JI Xiaoli xu Chao WANG Chunmei Department of Safety Science and Engineering Anhui University of Science and TechnologyHuainan 232001China Key Laboratory of Mine Safety and High Efficient Mining Jointly Built by Province and Education Ministry Anhui University of Science and TechnologyHuainan 232001China Department of Chemical Engineering and Explosives Anhui University of Science and TechnologyHuainan 232001China

A ternary early-strengthening agent consisting of calcium formate+triethanolamine+lithium sulfate was compounded with quercetin to shorten the setting time of cementitious materials while ensuring their early *** optimum ratio of the three early-strengthening agents was determined as 0.5%calcium formate+0.04%triethanolamine+0.4%lithium sulfate by response surface *** effects of the ternary early-strengthening agent composed of calcium formate+triethanolamine(TEA)+lithium sulfate on cementitious pore sealing materials under the synergistic effect of quercetin were studied by means of the performance tests of compressive strength,fluidity,and setting time,and the microstructural characterizations of X-ray powder diffractometer(XRD),thermogravimetry(TG-DSC)and scanning electron microscopy(SEM).The study shows that the synergistic effect of ternary early-strengthening agent and quercetin forms a multi-performance composite admixture for cementitious *** best performance was obtained with the compounding scheme of 0.5%calcium formate+0.04%triethanolamine+0.4%lithium sulfate ternary early-strengthening agent and 0.05%*** compressive strength of 1,3,7,and 28 d are 94.8%,39.8%,42%,and 28%higher than those of the blank group,*** initial time and final setting time are 41 and 57 minutes,*** to the microscopic analysis,the network and fibrous C-S-H gels generated by ternary early-strengthening agents are attached to the surface promoted by quercetin,which forms skeleton support while thickening and solidifying the cement slurry,which enhances the early compressive strength of the cement-based materials.

关键词： sealing material ternary early-strengthening agent quercetin synergetic effect response surface methodology

Enantio-divergent C–H borylation with two different ligands from a single chiral source

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Science China Chemistry 2025年第1期 226-232页

作者： Rongrong Du Senmiao xu State Key Laboratory for Oxo Synthesis and Selective Oxidation Lanzhou Institute of Chemical Physics Chinese Academy of Sciences College of Material Chemistry and Chemical Engineering Key Laboratory of Organosilicon Chemistry and Material TechnologyMinistry of Education Hangzhou Normal University University of Chinese Academy of Sciences

Reported here is an iridium-catalyzed enantio-divergent C（sp3）–H borylation of α-gem-dimethyl groups of trifluoromethyl ketone-derived hydrazones to construct a series of acyclic all-carbon quaternary stereocenters with a high level of chiral induction. Two different chiral bidentate boryl ligands from a common chiral source not only can switch the enantioselectivity but also are complementary in terms of the substrate scope.

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栽培方式对超级杂交稻生理特性和产量的影响及其灰色关联度分析

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湖南农业大学学报（自然科学版） 2007年第4期33卷 379-385页

作者：吴朝晖袁隆平青先国马国辉熊绪让中南大学生物科学与技术学院湖南长沙410083 国家杂交水稻工程技术研究中心湖南长沙410125

为筛选并建立超级杂交稻集大穗与多穗于一体的高产栽培技术体系,以水稻强化栽培技术体系(SRI)为基本模式,研究了多种栽培方式对超级杂交稻两优0293生长发育特性和产量的影响,并运用灰色关联度分析方法对主要经济性状与实际产量、不同栽... 详细信息

为筛选并建立超级杂交稻集大穗与多穗于一体的高产栽培技术体系,以水稻强化栽培技术体系(SRI)为基本模式,研究了多种栽培方式对超级杂交稻两优0293生长发育特性和产量的影响,并运用灰色关联度分析方法对主要经济性状与实际产量、不同栽培方式与理想方式分别进行灰色关联度分析.结果表明:与产量关联最密切的性状为有效穗数,其次为千粒重、结实率;产量最高的栽培方式为密度18×104穴/hm2,规格33.3 cm×(10+23.3)cm的宽窄行密株错位形式,该方式的综合表现与目标栽培方式关联最紧密.

关键词：超级杂交稻栽培方式生理特性产量灰色关联度两优0293

Bearing Fault Diagnosis Based on the Markov Transition Field and SE-IShufflenetV2 Model

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Structural Durability & Health Monitoring 2025年第1期19卷 125-144页

作者： Chaozhi Cai Tiexin xu Jianhua Ren Yingfang xue School of Mechanical and Equipment Engineering Hebei University of EngineeringHandan056038China

A bearing fault diagnosis method based on the Markov transitionﬁeld(MTF)and SEnet(SE)-IShufﬂenetV2 model is proposed in this paper due to the problems of complex working conditions,low fault diagnosis accuracy,and poor generalization of rolling ***,MTF is used to encode one-dimensional time series vibration sig-nals and convert them into time-dependent and unique two-dimensional feature ***,the generated two-dimensional dataset is fed into the SE-IShufﬂenetV2 model for training to achieve fault feature extraction and classiﬁ*** paper selects the bearing fault datasets from Case Western Reserve University and Paderborn University to experimentally verify the effectiveness and superiority of the proposed *** generalization performance of the proposed method is tested under the variable load condition and different signal-to-noise ratios(SNRs).The experimental results show that the average accuracy of the proposed method under different working conditions is 99.2%without adding *** accuracy under different working conditions from 0 to 1 HP is 100%.When the SNR is 0 dB,the average accuracy of the proposed method can still reach 98.7%under varying working ***,the bearing fault diagnosis method proposed in this paper is characterized by high accuracy,strong anti-noise ability,and ***,the proposed method can also overcome the inﬂuence of variable working conditions on diagnosis accuracy,providing method support for the accurate diagnosis of bearing faults under strong noise and variable working conditions.

关键词： Bearings Markov transitionﬁeld SE-IShufﬂenetV2

居家协议护理对提高血液透析患者液体摄入依从性的有效性研究

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中国实用护理杂志 2009年第26期25卷 4-6页

作者：刘晓芳唐宁波徐航张媛媛梁志金广西中医学院附属瑞康医院肾内科

目的探讨以协议护理理论为指导的居家护理对提高血液透析(HD)患者液体摄入依从性的效果。方法将48例液体摄入不依从的血液透析患者随机分为观察组和对照组各24例。对照组予以常规护理;观察组在此基础上实施以协议护理理论为指导的居家... 详细信息

目的探讨以协议护理理论为指导的居家护理对提高血液透析(HD)患者液体摄入依从性的效果。方法将48例液体摄入不依从的血液透析患者随机分为观察组和对照组各24例。对照组予以常规护理;观察组在此基础上实施以协议护理理论为指导的居家护理指导1个月。指导结束后对2组患者随访3个月,评价2组患者干预前后的液体摄入依从性;家庭支持与透析间期体质量增长相对值(即体质量增长与干体重的比值)关系。结果干预后观察组患者体质量增长相对值显著低于对照组;依从程度显著高于对照组;家庭支持水平显著高于对照组;家庭支持与体质量增长相对值呈负相关。干预后观察组患者体质量增长相对值、家庭支持水平及液体摄入依从程度均较干预前有显著改善。结论以协议护理理论为指导的居家护理指导有利于指导家属向患者提供有效的家庭支持,提高患者液体摄入依从性,使透析间期体质量增加控制在理想范围。

关键词：协议护理居家护理液体摄入依从性

Morphological Mechanism and Experimental Verification of Self-healing of Basalt-fiber Modified Water-soaked Asphalt

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Journal of Wuhan University of Technology(Materials Science) 2025年第1期40卷 171-186页

作者： XIAO Minmin DONG Jinyong LI Chunyan GUO xu REN Jianguo School of Urban Construction and Safety Engineering Shanghai Institute of TechnologyShanghai 201418China

This study investigates the mechanism of action of representative molecules of basalt fibers on the healing of water-soaked *** parameters,morphological characteristics,interfacial healing energy,and interfacial healing strength were analyzed using molecular dynamics and macroscopic tests under different time,temperature,and water conditions to evaluate the specific states and critical conditions involved in *** results indicate that basalt-fiber molecules can induce rearrangement and a combination of water-soaked asphalt at the healing *** groups with different bonding states increase the interfacial adsorption capacity of water-soaked *** interaction between basalt fiber molecules and water molecules leads to a"hoop"phenomenon,while aromatics-2 molecules exhibit a"ring band aggregation"*** former reduces the miscibility of water and asphalt molecules,while the latter causes slow diffusion of the ***,a micro-macro dual-scale comparison of interfacial healing strength was conducted at temperatures of 297.15 and 312.15 K to identify the strength transition point and critical temperature of 299.4 K during the self-healing process of basalt-fiber modified water-soaked asphalt.

关键词： water-soaked asphalt basalt-fibers self-healing properties moisture status molecular characterization

Recent progress in exploring heterogeneous catalyst surface chemistry with near ambient pressure XPS

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Science China Chemistry 2025年

作者： Yuanjie xu Zemin An Yu Tang Institute of Molecular Engineering Plus Institute of Molecule Catalysis and In Situ/Operando Studies College of Chemistry Fuzhou University

X-ray photoelectron spectroscopy(XPS) is a crucial surface analysis technique that has become a key tool in the study of heterogeneous catalysis. Detecting surface chemistry under conditions that closely mimic actual industrial catalytic processes is essential for understanding the mechanisms involved. In the past decade, near ambient pressure X-ray photoelectron spectroscopy(NAP-XPS) has been increasingly utilized to study the surface chemistry of catalysts during heterogeneous catalytic processes, offering insights into structure-performance correlations. This review begins with a brief overview of NAP-XPS instrumentation. Next, we discuss the application of NAP-XPS in the study of thermal catalysis reactions, followed by a summary of the research on catalyst restructuring under reaction conditions. Additionally, we address the challenges and future perspectives for the development and application of NAP-XPS. Catalysis is inherently dynamic, requiring an understanding of the real-time behavior of catalysts under varying conditions. Therefore, future improvements in the ability to probe reaction intermediates with higher spatial and temporal resolution under conditions that closely mimic industrial environments are needed.

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某型航空发动机油气分离器内两相流动数值模拟

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燃气涡轮试验与研究 2010年第1期23卷 47-50,14页

作者：贾春强徐让书马前容中国燃气涡轮研究院四川江油621703 沈阳航空工业学院辽宁沈阳110034

本文利用离散相模型(DPM)和雷诺应力模型(RSM)对某型航空发动机油气分离器进行了数值模拟,得到了流动速度场和油滴运动轨迹。通过对模拟结果的分析,揭示了油气分离的机理,并计算出了分离效率,这对航空发动机油气分离器的优化设计具有重... 详细信息

本文利用离散相模型(DPM)和雷诺应力模型(RSM)对某型航空发动机油气分离器进行了数值模拟,得到了流动速度场和油滴运动轨迹。通过对模拟结果的分析,揭示了油气分离的机理,并计算出了分离效率,这对航空发动机油气分离器的优化设计具有重要参考价值。

关键词：油气分离器数值模拟 DPM模型气液两相流

Optimization Strategies of Na_(3)V_(2)(PO_(4))_(3) Cathode Materials for Sodium‑Ion Batteries

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Nano-Micro Letters 2025年第2期17卷 204-251页

作者： Jiawen Hu Xinwei Li Qianqian Liang Li xu Changsheng Ding Yu Liu Yanfeng Gao School of Materials Science and Engineering Shanghai UniversityShanghai 200444People’s Republic of China Shanghai Institute of Ceramics Chinese Academy of SciencesShanghai 200050People’s Republic of China

Na_(3)V_(2)(PO_(4))_(3)(NVP)has garnered great attentions as a prospective cathode material for sodium-ion batteries(SIBs)by virtue of its decent theoretical capacity,superior ion conductivity and high structural ***,the inherently poor electronic conductivity and sluggish sodium-ion diffusion kinetics of NVP material give rise to inferior rate performance and unsatisfactory energy density,which strictly confine its further application in ***,it is of significance to boost the sodium storage performance of NVP cathode *** to now,many methods have been developed to optimize the electrochemical performance of NVP cathode *** this review,the latest advances in optimization strategies for improving the electrochemical performance of NVP cathode material are well summarized and discussed,including carbon coating or modification,foreign-ion doping or substitution and nanostructure and morphology *** foreign-ion doping or substitution is highlighted,involving Na,V,and PO_(4)^(3−)sites,which include single-site doping,multiple-site doping,single-ion doping,multiple-ion doping and so ***,the challenges and prospects of high-performance NVP cathode material are also put *** is believed that this review can provide a useful reference for designing and developing high-performance NVP cathode material toward the large-scale application in SIBs.

关键词： Sodium-ion batteries Na_(3)V_(2)(PO_(4))_(3) Cathode materials Electrochemical performance Optimization strategies