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Deoxygenative alkylation of tertiary amides using alkyl iodides under visible light

Science China Chemistry 2022年第11期65卷 2231-2237页

作者： feng Zhao feng Jiang Xiaoming Wang The Education Ministry Key Lab of Resource Chemistry and Shanghai Key Laboratory of Rare Earth Functional Materials College of Chemistry and Materials ScienceShanghai Normal UniversityShanghai 200234China State Key Laboratory of Organometallic Chemistry Center for Excellence in Molecular SynthesisShanghai Institute of Organic ChemistryChinese Academy of SciencesShanghai 200032China School of Chemistry and Materials Science Hangzhou Institute for Advanced StudyUniversity of Chinese Academy of SciencesHangzhou310024China

It is an unceasing goal for organic chemists to develop new catalytic methodologies for functional group transformations of widespread molecular structures. Amides are readily available from simple and reliable reactions, which are common structural units found in biologically active compounds. Consequently, they are attractive to be exploited in amine synthesis by reductive cross coupling. However, deoxygenative functionalization of amides is a long-standing challenge owing to the inertness of the resonance-stabilized amide C=O bond. In this work, a deoxygenative alkylation strategy was demonstrated, which combines amides and alkyl iodides to build structurally diverse tertiary alkylamines in a single step. Compared with previous deoxygenative alkylation of amides using organometallic reagents as functional partner, this work uses stable and easily available alkyl halides as functionalization reagents. The versatile and flexible strategy plus structural and functional diversity of readily available amides and alkyl iodides renders it highly appealing for the streamlined synthesis of tertiary amines and would be of much interest in areas such as pharmaceutical and agrochemical research.

关键词： deoxygenative alkylation amide transformation alkyl radical alkylamine visible light

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柳江盆地髫髻山组凝灰岩地球化学与熔体包裹体水含量特征

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岩矿测试 2025年第1期44卷 88-101页

作者：赵汇珍陈勇涂聪冯艳伟中国石油大学(华东)深层油气全国重点实验室山东青岛266580 中国石油大学(华东)地球科学与技术学院山东青岛266580 中国科学技术大学地球和空间科学学院安徽合肥230026

水作为岩浆体系中最主要的挥发组分,对岩浆的形成和演化有重要的影响,柳江盆地髫髻山组岩浆岩是燕山期火山活动的重要产物,尽管前人对其地球化学特征进行了大量研究,但关于柳江盆地燕山期岩浆中的水含量仍不清楚。熔体包裹体记录了原始... 详细信息

水作为岩浆体系中最主要的挥发组分,对岩浆的形成和演化有重要的影响,柳江盆地髫髻山组岩浆岩是燕山期火山活动的重要产物,尽管前人对其地球化学特征进行了大量研究,但关于柳江盆地燕山期岩浆中的水含量仍不清楚。熔体包裹体记录了原始岩浆信息,是获取岩浆水含量特征的最直接样品。本文基于全岩地球化学分析,利用标准样品建立了显微激光拉曼光谱定量熔体包裹体水含量的标定曲线,并对柳江盆地髫髻山组下部流纹质岩屑-晶屑凝灰岩中石英斑晶内的原生熔体包裹体进行了水含量定量分析。结果表明:髫髻山组下部凝灰岩样品具有富Si、Al、大离子亲石元素富集、高场强元素亏损、轻稀土富集、重稀土亏损、负Eu异常、Sr含量低等特点;熔体包裹体中水含量的定量分析结果为0.99%~4.98%,平均水含量为2.62%,与前人统计的酸性岩浆水含量基本一致。地球化学特征和熔体包裹体水含量分析结果共同揭示了研究区髫髻山期早期为富水酸性岩浆。结合髫髻山期样品的熔体包裹体水含量测定结果及其早期的大规模火山喷发背景,本文认为岩浆中高含水量增强了岩浆系统的喷发动力,是诱发研究区髫髻山期早期大规模火山爆发的有利因素之一。

关键词：柳江盆地髫髻山组凝灰岩熔体包裹体水含量显微激光拉曼光谱法

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Column envelope meshing pair and its design method for single screw compressors

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2009年第1期10卷 31-36页

作者： Wei-feng WU Quan-ke feng School of Energy and Power Engineering Xi 'an Jiaotong University Xi 'an 710049 China

A single screw compressor (SSC) is an important component found in many refrigeration ***,the durability is not so good because of the friction between its meshing *** the column envelope meshing pair was pro-posed to prolong the operating life of SSCs,although it has not been applied to commercial refrigeration *** accelerate the industrial application,a mathematical model for analyzing the column envelope meshing pair is established based on the geometry and *** giving the flanks of column envelope grooves are obtained,and teeth flank meshing with the groove is *** show that this model could be applicable in the design of the column envelope type SSC.

关键词： Column envelope Single screw compressor (SSC) Meshing pair design Mathematical model

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STOCHASTIC MAXIMUM PRINCIPLE FOR MIXED REGULAR-SINGULAR CONTROL PROBLEMS OF FORWARD-BACKWARD SYSTEMS

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Journal of Systems Science & Complexity 2013年第6期26卷 886-901页

作者： ZHANG feng School of Mathematics and Quantitative Economics Shandong University of Finance and Economics

This paper considers a stochastic optimal control problem of a forward-backward system with regular-singular controls where the set of regular controls is not necessarily convex and the regular control enters the diffusion *** control problem is difficult to solve with the classical method of spike *** authors use the approach of relaxed controls to establish maximum principle for this stochastic optimal control *** optimality conditions are also investigated.

关键词： Forward-backward system maximum principle relaxed control singular control.

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Frequency Weighting Filter Design for Automotive Ride Comfort Evaluation

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Chinese Journal of Mechanical Engineering 2016年第4期29卷 727-738页

作者： DU feng School of Mechanical and Automotive Engineering South China University of Technology

Few study gives guidance to design weighting filters according to the frequency weighting factors,and the additional evaluation method of automotive ride comfort is not made good use of in some *** on the regularities of the weighting factors,a method is proposed and the vertical and horizontal weighting filters are *** whole frequency range is divided several times into two parts with respective *** each division,a parallel filter constituted by a low-and a high-pass filter with the same cutoff frequency and the quality factor is utilized to achieve section *** cascading of these parallel filters obtains entire *** filters own a high ***,low order filters are preferred in some *** bilinear transformation method and the least P-norm optimal infinite impulse response（IIR） filter design method are employed to develop low order filters to approximate the weightings in the *** addition,with the window method,the linear phase finite impulse response（FIR） filter is designed to keep the signal from distorting and to obtain the staircase *** the same case,the traditional method produces 0.330 7 m · s^–2 weighted root mean square（r.m.s.） acceleration and the filtering method gives 0.311 9 m · s^–2 *** fourth order filter for approximation of vertical weighting obtains 0.313 9 m · s^–2 *** factors of the acceleration signal weighted by the weighting filter and the fourth order filter are 3.002 7 and 3.011 1,*** paper proposes several methods to design frequency weighting filters for automotive ride comfort evaluation,and these developed weighting filters are effective.

关键词： frequency weighting ride comfort evaluation least P-norm optimal method bilinear transformation weighting filter design

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植物源外泌体样纳米囊泡刺激成骨细胞、抑制破骨细胞并促进成骨

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中国组织工程研究 2025年第31期29卷 6765-6771页

作者：药文鑫王毅蔡林冯晓波武汉大学中南医院疼痛科湖北省武汉市430071 武汉大学中南医院脊柱与骨肿瘤科湖北省武汉市430071

背景:骨质疏松症易引发病理性骨折且严重影响患者的生活质量,植物源外泌体样纳米囊泡在调节骨质疏松症骨平衡方面发挥着重要作用。目的:综述不同植物源外泌体样纳米囊泡在骨质疏松症治疗中的研究现状与展望。方法:通过计算机在PubMed、W... 详细信息

背景:骨质疏松症易引发病理性骨折且严重影响患者的生活质量,植物源外泌体样纳米囊泡在调节骨质疏松症骨平衡方面发挥着重要作用。目的:综述不同植物源外泌体样纳米囊泡在骨质疏松症治疗中的研究现状与展望。方法:通过计算机在PubMed、Web of Science、中国知网中检索1995年1月至2024年3月发表的相关文献,以“osteoporosis,plant-derived exosome-like nanovesicles,exosomes,osteoblasts,osteoclasts”为英文检索词,以“骨质疏松症,植物源外泌体样纳米囊泡,外泌体,成骨细胞,破骨细胞”为中文检索词,最终纳入53篇文献进行分析。结果与结论:植物源外泌体样纳米囊泡具有生物相容性、低毒性和天然靶向性等优点,这些特性不仅确保了其在体内的稳定存在与有效作用,还避免了不必要的免疫反应,为长期治疗策略的设计奠定了基础。植物源外泌体样纳米囊泡可以通过刺激成骨细胞增殖、抑制破骨细胞分化以及促进成骨-抑制破骨双重作用抗骨质疏松症;此外,部分植物源外泌体样纳米囊泡因具有骨靶向性,未来或将成为新型示踪靶标和治疗方案广泛应用于骨质疏松症治疗过程中。

关键词：骨质疏松症植物源性外泌体样纳米囊泡外泌体成骨细胞破骨细胞工程化外泌体

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ELASTIC-PLASTIC DYNAMIC RESPONSE OF A CANTILEVER BEAM SUBJECTED TO OBLIQUE IMPACT AT ITS TIP

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Acta Mechanica Solida Sinica 2005年第4期18卷 316-325页

作者： Xi feng Liu feng Shandong Institute of Architecture and Engineering Jinan 250101 China

By employing large deformation governing equations expressed in the form of finite difference, the dynamic responses of an elastic, perfectly plastic cantilever subjected to an oblique impact at its tip was numerically studied. Through analyzing the instantaneous distribution of the yield function （φ = ｜M/Mo｜＋（N/No）^2）, bending moment and axial force during the early stage of the response, the elastic-plastic deformation mechanism and the influence of axial component of an oblique impact on the dynamic response of a cantilever beam were discussed. The present analysis shows that the deformation mechanism of an elastic-plastic cantilever subjected to an oblique impact consists of four phases, i.e. ‘the expanding compressed plastic region＇ mode; the ‘generalized traveling plastic hinge＇ and ‘shrinking plastic region＇ mixed mode; the ‘stationary plastic hinge＇ mode and ‘elastic vibration＇ mode. Compared with the two-phase deformation mode obtained by using the rigid, perfectly plastic approach, the mode of shrinking plastic region that occurred instantly after the oblique impact and the mode of stationary hinge were both confirmed. The primary features of the deformation mechanism are captured by both analysis methods. It has also been found that the beam＇s deformation is mainly controlled by the axial component of the oblique impact in the early phase of the dynamic response, the deformation mechanism is obviously different from the case of a transverse impact. With further development of the response, the axial component attenuates rapidly and gives negligible contribution to the yielding of the beam cross-section. At the same time, the bending moments along the cantilever develop gradually and dominate the beam＇s deformation. The numerical results indicate that the mass, impact speed and oblique angle are the important factors that influence the elastic-plastic dynamic response of a cantilever beam.

关键词： oblique impact elastoplasticity large deformation dynamic response cantilever

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圈层化网络社群对青少年的伦理挑战及其应对

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教学与管理 2025年第1期 34-38页

作者：刘昊琛冯永刚山东师范大学教育学部济南250014

青少年在网络空间构筑了基于共同兴趣和偏好的“新社群”。网络社群内部的圈层化趋势加强了青少年之间的联系与共鸣,在一定程度上重塑了他们的社会认知和伦理判断。然而,这种圈层化也带来了新型场域对伦理空间的冲击、圈层区隔对伦理关... 详细信息

青少年在网络空间构筑了基于共同兴趣和偏好的“新社群”。网络社群内部的圈层化趋势加强了青少年之间的联系与共鸣,在一定程度上重塑了他们的社会认知和伦理判断。然而,这种圈层化也带来了新型场域对伦理空间的冲击、圈层区隔对伦理关系的界分、特定惯习对伦理实践的影响和微观规训对伦理意识的裹挟等问题,将他们置于伦理挑战的情境中进行考量。鉴于此,创构主流舆论传播新格局、释放网络圈层整合共振力、激活多元话语互促生命力、注重外部治理和内部自律的统一性,对于网络社会治理和构建网络空间命运共同体具有重要意义。

关键词：圈层化网络社群青少年伦理挑战

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Prenatal ultrasonography and genetic analysis of fetal cleidocranial dysplasia:A case report

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World Journal of Clinical Cases 2025年第10期13卷 28-34页

作者： feng Wang Pei-feng Dai Wen-Juan Gao Department of Ultrasonography Weifang People’s HospitalWeifang 261000Shandong ProvinceChina

BACKGROUND Cleidocranial dysplasia(CCD)is an infrequent clinical condition with an autosomal dominant inheritance *** is characterized by abnormal clavicles,patent sutures and fontanelles,supernumerary teeth,and short *** 60%-70%of patients with CCD have mutations in the RUNX family transcription factor 2 ***,prenatal diagnosis of CCD is difficult when the family history is *** SUMMARY We report a rare case of fetal CCD with an unknown family history,confirmed by prenatal ultrasonography and genetic testing at a gestational age of 16 *** genetic reports indicated that the fetus carried pathogenic mutations in the RUNX family transcription factor 2 gene(c.674G>A).After careful consideration,the pregnant woman and her family decided to continue the *** Definitive prenatal diagnosis of CCD should include family history,ultrasound diagnosis,and genetic analysis,especially if family history is unknown.

关键词： Cleidocranial dysplasia Genetic analysis Ultrasonic diagnosis Prenatal Case report

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Bulk viscosity of interacting magnetized strange quark matter

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Nuclear Science and Techniques 2021年第10期32卷 101-109页

作者： Jian-feng Xu School of Physics and Electrical Engineering AnYang Normal UniversityAnyang 455000China

The bulk viscosity of interacting strange quark matter in a strong external magnetic field B m with a real equation of state is *** is found that interquark interactions can significantly increase the bulk viscosity,and the magnetic field B_(m) can cause irregular oscillations in both components of the bulk viscosity,ξ||(parallel to B_(m))and ξ⊥(perpendicular to B_(m)).A comparison with non-interacting strange quark matter reveals that when B_(m) is sufficiently large,ξ⊥is more affected by interactions than ξ||.Additionally,the quasi-oscillation of the bulk viscosity with changes in density may facilitate the for-mation of magnetic ***,the resulting r-mode instability windows are in good agreement with observational data for compact stars in low-mass X-ray ***,the r-mode instability window for interacting strange quark matter in high magnetic fields has a minimum rotation frequency exceeding 1050 Hz,which may explain the observed very high spin frequency of a pulsar with V=1122 Hz.

关键词： Strange quark matter Bulk viscosity Strong magnetic field Strange star R-mode instability window

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