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Heterocatalytic ethylene methoxycarbonylation via a pseudo-hydride pathway over Pt_(1)/MoS_(2)

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Science China Chemistry 2024年第8期67卷 2427-2428页

作者： bo-Hang zhao Bin Zhang Institute of Molecular Plus Department of ChemistrySchool of ScienceTianjin UniversityTianjin 300072China

Ethylene (C2H4) methoxycarbonylation (EMC) with CO and methanol (CH3OH) to methyl propanoate (MP) is industrially important due to its 100% atom efficiency [1].However, the heavy reliance on homogeneous Pd-based catalysts and strong acid media over commercial EMC processes still causes economic and environmental concerns [2]. At present, supported single-atom catalysts (SACs) can serve as bridges for accessing homogeneous catalysts in traditional heterogeneous catalytic processes.

关键词： processes. catalytic hydride

基于神经网络的优化算法在EDA中应用研究进展

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计算机应用研究 2025年第1期42卷 1-10页

作者：赵晨晖贺珊刘先明郭东辉厦门大学电子科学与技术学院福建厦门361005 福建省集成电路设计工程技术研究中心福建厦门361005

为了应对芯片设计复杂度的提升,电子设计自动化工具和方法也在不断进步。然而,EDA需要协调达到最佳的功率、性能和面积,通常其不能保证最优的解决方案。EDA工具在电路设计阶段包括逻辑综合、布局布线及验证等均属于多目标、多约束的非... 详细信息

为了应对芯片设计复杂度的提升,电子设计自动化工具和方法也在不断进步。然而,EDA需要协调达到最佳的功率、性能和面积,通常其不能保证最优的解决方案。EDA工具在电路设计阶段包括逻辑综合、布局布线及验证等均属于多目标、多约束的非线性规划求解过程,且为了更好解决求解中的不确定性和易于出现局域极值等难题,基于神经网络的优化算法已被集成到EDA工具的设计流程中。首先对EDA中的优化问题、多目标优化计算及基于神经网络的优化算法进行了简要概述,继而详细梳理了基于神经网络的优化算法在逻辑综合、布局布线及验证等不同设计阶段中的优化求解方法,并阐述了当前研究所面临的挑战与机遇,希望为集成电路自动化设计及相关领域研究提供参考。

关键词：电子设计自动化非线性规划多目标优化神经网络优化计算

RNA silencing:From discovery and elucidation to application and perspectives

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Journal of Integrative Plant Biology 2022年第2期64卷 476-498页

作者： Jian-Hua zhao Hui-shan Guo State Key Laboratory of Plant Genomics Institute of Microbiologythe Chinese Academy of SciencesBeijing100101 China CAS Center for Excellence in Biotic Interactions University of the Chinese Academy of SciencesBeijing100049 China

RNA silencing(or RNA interference,RNAi)is a conserved mechanism for regulating gene expression in *** discovery of natural trans-kingdom RNAi indicated that small RNAs act as signaling molecules and enable communication between organisms in different *** phenomenon and potential mechanisms of trans-kingdom RNAi are among the most exciting research *** better understand trans-kingdom RNAi,we review the history of the discovery and elucidation of RNAi *** on canonical RNAi mechanisms,we summarize the major points of divergence around RNAi pathways in the main eukaryotes’kingdoms,including plants,animals,and *** review the representative incidents associated with the mechanisms and applications of trans-kingdom RNAi in crop protection,and discuss the critical factors that should be considered to develop successful trans-kingdom RNAi-based crop protection strategies.

关键词： crop protection gene expression RNA silencing small RNAs trans-kingdom RNAi

Two new C_(21) steroidal glycosides isolated from Cynanchum komarovii

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Chinese Journal of Natural Medicines 2018年第8期16卷 610-614页

作者： zhao Dan SU shan-shan CHEN Shao-Fei LU Xiao-Jie CHEN Gang WANG Yu-bo SU Guang-Yue PEI Yue-Hu Key Laboratory of Structure-Based Drug Design & Discovery Ministry of EducationShenyang Pharmaceutical University School of Traditional Chinese Materia Medica Shenyang Pharmaceutical University Testing Laboratory Qinghai Entry Exit Inspection and Quarantine Bureau School of Pharmacy Jinzhou Medical University

The present study was designed to further investigate the C_(21) steroidal glycosides in Cynanchum *** new steroidal glycosides based on a 13,14:14,15-disecopregnane-type aglycone,komaroside P(1) and komaroside Q(2),together with three known compounds(3-5) were isolated from the whole herbs of Cynanchum *** aglycones of compounds 1 and 2 were two new *** structures were elucidated on the basis of 1 D,2 D NMR spectroscopic data and acid *** the compounds(1-5) showed potent inhibitory activities against human leukemia cell lines(HL-60) with IC50 values ranging from 16.6 to 26.3 μmol·L^(-1),compared to the positive control 5-fluorouracil(6.4 μmol·L^(-1)).

关键词： Cynanchum komarovii C21 steroidal glycosides Cytotoxic activity

Efficient thrust generation in robotic fish caudal fins using policy search

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IET Cyber-Systems and Robotics 2019年第1期1卷 38-44页

作者： Yixi shan Yagiz EBayiz bo Cheng Department of Mechanical Engineering The Pennsylvania State UniversityState CollegeUSA

Thrust generation is a crucial aspect of fish locomotion that depends on a variety of morphological and kinematic *** this work,the kinematics of caudal fin motion of a robotic fish are optimised *** robotic fish actuates its caudal fin with flapping and rotation motion,and also measures the fin hydrodynamic force and *** nine designs of the caudal fins are investigated,with three different shapes(or inclination angles)and three *** optimisation is based on a policy search(PS)algorithm,which is used to maximise the thrust-generation efficiency of the caudal *** authors first parametrise fin spanwise-rotation as a sinusoidal function using rotation amplitude and phase delay and test whether it is beneficial to thrust-generation *** result shows that the rotation does not contribute to the efficiency,as the efficiency is maximised at zero ***,the authors optimise flapping amplitude and trajectory profile without fin *** show that smaller flapping amplitude results in higher efficiency and linear flapping trajectories are preferred over sinusoidal *** that have the highest flexibility are more efficient in thrust generation although they generate less thrust,while an inclination angle of 30°yields the most efficient fin shape.

关键词： policy robotic rotation

Multilinear Fractional Hausdorff Operators

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Acta Mathematica Sinica,English Series 2014年第8期30卷 1407-1421页

作者： Da shan FAN Fa You zhao Department of Mathematical Sciences University of Wisconsin-Milwaukee Department of Mathematics Shanghai University

In this paper,by introducing the space with weak mixed norms,weak type estimates of two kinds of multilinear fractional Hausdorff operators RΦ,β and SΦ,β on Lebesgue spaces are *** virtue of Marcinkiewicz interpolation,strong type estimates of these two operators on Lebesgue spaces are also *** methods shed some new light on dealing with the case of non-radial function Φ.

关键词： Multilinear fractional Hausdorff operators bilinear fractional Hardy operator weak type,strong type

High-Order Hamilton's Principle and the Hamilton's Principle of High-Order Lagrangian Function

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Communications in Theoretical Physics 2008年第2期49卷 297-302页

作者： zhao Hong-Xia MA shan-Jun College of Physics and Communication Electronics Jiangxi Normal University Nanchang 330022 China

In this paper, based on the theorem of the high-order velocity energy, integration and variation principle, the high-order Hamilton＇s principle of general holonomic systems is given. Then, three-order Lagrangian equations and four-order Lagrangian equations are obtained from the high-order Hamilton＇s principle. Finally, the Hamilton＇s principle of high-order Lagrangian function is given.

关键词： Hamilton's principle high-order velocity energy integration and variation principle Lagrangian function

Late Paleozoic–Early Mesozoic tectonic evolution of the Zongwulong shan-Qinghai Nanshan tectonic belt in the northern Qaidam continent， northern Tibet

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Journal of Earth Science 2025年

作者： Yonghui zhao Chen Wu Jie Li Peter J.Haproff Lin Ding State Key Laboratory of Tibetan Plateau Earth System and Resources Environment (TPESRE)， Institute of Tibetan Plateau Research， Chinese Academy of Sciences University of Chinese Academy of Sciences Chongqing Key Laboratory of Complex Oil and Gas Field Exploration and Development， Chongqing University of Science and Technology Department of Earth and Ocean Sciences， University of North Carolina Wilmington

The Zongwulong shan-Qinghai Nanshan tectonic belt of the northern Tibet Plateau experienced a protracted tectonic history， including the openings and closures of the Proto- and Paleo-Tethyan Oceans. Although the tectonic belt has been extensively studied， details regarding the tectonic processes involved in its development remain controversial. To better constrain the tectonic processes of this tectonic belt， we conducted detailed field geological mapping， zircon U-Pb geochronology， and whole-rock geochemical and Sr-Nd isotopic analyses. Our results show that intrusive rocks in the tectonic belt crystallized in ca. 292–233 Ma， perhaps in an arc/subduction setting. Geochemical and Sr-Nd isotopic data suggest that early Permian–late Triassic ultramafic-intermediate intrusions were sourced from the enriched mantle， whereas intermediate-acidic rocks were sourced from mixed crust-mantle. We present the tectonic model that involves: (1) Early Devonian–early Permian intracontinental extension occurred in the northern margin of the Qaidam continent (ca. 416 Ma–292 Ma); (2) Early Permian–late Triassic northward subduction of the Paleo-Tethyan Ocean resulted in arc magmatism (ca. 292 Ma–233 Ma); and (3) subsequent late Triassic intracontinental extension (ca. 233 Ma–215 Ma). Our results suggest that the late Paleozoic–early Mesozoic development of the Zongwulong shan-Qinghai Nanshan was related to the opening， subduction， and slab retreat of the Paleo-Tethyan Ocean， which has key implications for the tectonic evolution of the northern Tibetan Plateau.

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Cognition-Based Interactive Phases and Strategies in Teaching Academic Reading

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Journal of Electronic Science and Technology 2017年第1期15卷 33-40页

作者： zhao Gao shan Gao Qi Yang School of Foreign Languages University of Electronic Science and TechnologyChengdu 610054China

Academic English reading requires deeper cognitive involvement in addition to language proficiency and plays a vital role in moulding a critical mindset. However, cognitive progress is seldom targeted in classroom teaching. This study proposed a teaching method of three reading phases in terms of cognitive mechanism and communicative teaching *** university freshmen of non-English major participated in the study, who were taking the course of Academic English Reading in the 2nd semester. The data were collected from self-report Research Skills Assessment twice and semi-structured interview, and analyzed with paired sample t test and Pearson correlation. The results showed that 1） “critical thinking”, “organizing ideas”, and “finding information” were believed to improve significantly at the end of the course; 2） reading skill was associated with writing skill and the sense of “big picture” in self perception; 3） the cognition-based interactive reading instruction was acknowledged to be conducive to academic reading. It complements Academic English reading pedagogy by juxtaposing the need for both individual cognition and group interaction in classroom teaching.

关键词： Reading classroom skill proficiency interview thinking acknowledged instruction comprehension cognition