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Emerging progress: photochemical transformation of nitroso compounds

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Science China Chemistry 2024年

作者： Ze-Le Chen Qiang-Qiang Li Armido studer Jun Xuan Anhui Province Key Laboratory of Chemistry for Inorganic/Organic Hybrid Functionalized Materials School of Chemistry & Chemical Engineering Anhui University Organisch-Chemisches Institut Universitat Münster

Nitroso compounds have emerged as highly valuable reaction partners or reagents in organic synthesis due to their rich *** versatile profile of these compounds allows them to function as electrophiles, nucleophiles, diradicals, and radical acceptors in diverse transformations. In recent years, notable progress has been made in harnessing photochemical reactions with nitroso compounds to prepare N,O-containing structures using mild and eco-friendly conditions. Various nitroso compounds like nitrosoarenes, acyloxy nitroso compounds, N-nitrosoamines and nitrites have received significant attention for their ability to introduce NO moieties into complex molecules that are otherwise difficult to access. In this review, we provide an overview of the recent advancements in the visible light-induced conversion of nitroso compounds, with particular emphasis on their role as bifunctional reagents and acceptors of radicals, carbenes and nitrenes.

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新型直流力矩电动机

稀土 1981年第S1期 64-68页

作者： Philip a.studer ,成永顺

改进电磁传动装置的探索还在继续中,我们已经看到了直接驱动力矩电动机的推广使用,它的输出特性能与负载条件相匹配,消除了齿论啮合间隙,加速度高,並有良好的伺服带宽,通过电子换向器消除了电刷的磨损,同时由于消除了易于磨损的滑动接触... 详细信息

改进电磁传动装置的探索还在继续中,我们已经看到了直接驱动力矩电动机的推广使用,它的输出特性能与负载条件相匹配,消除了齿论啮合间隙,加速度高,並有良好的伺服带宽,通过电子换向器消除了电刷的磨损,同时由于消除了易于磨损的滑动接触,因而更加可靠。本文将讨论消除由于缝隙效应和磁滞而引起的伺服电机齿槽效应的方法,並进一步提高电磁驱动系统的效率和线性度,使电动机的动力学特性提高一个数量级。这种新研制的电动机是无铁芯电枢无电刷直流电动机,由于采用了稀土永磁体,旋转磁场磁体组合件重量轻而转动惯量低,才有可能将电枢导体放置到电动机的气隙中,制成了这种电动机。本文报导了以这种新设计想思设计的样机所能达到特性和重量有效系数,也谈到了这类电动机在位置控制和速度控制系统中应用。

关键词：电动机动力学特性电马达发动机电枢电机构件永磁体力矩波动气隙绕组线圈电枢导体齿槽效应无铁心铁芯电器构件

Chemistry With N-Centered Radicals Generated by Single-Electron Transfer-Oxidation Using Photoredox Catalysis

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CCS Chemistry 2019年第1期1卷 38-49页

作者： Heng Jiang Armido studer Organisch-Chemisches Institut Westfälische Wilhelms-UniversitätMünster 48149Germany Fujian Institute of Research on the Structure of Matter Chinese Academy of SciencesWest Fuzhou 350002China

This review covers the recent literature on oxidative generation of N-centered radicals using photoredox *** concept of proton-coupled electron transfer is briefly *** of such reactive N-centered radicals in cascade processes comprising arene amidation,alkene amidation,C—C bond cleavage reactions,and remote C—H functionalization are *** addition,novel reagents allowing for clean oxidative N-radical generation are discussed.

关键词： radicals photoredox catalysis synthetic methods

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2019年度studer再次提升市场份额

金属加工（冷加工） 2020年第5期 28-29页

作者： studer studer

在2018年创下纪录后,studer公司再次在2019年获得好成绩。2019年成为studer历史业绩排行榜上第三好年份。尽管市场环境艰难,但studer再次提升了市场份额。其成功的原因之一是新客户的订单比例很高,接近40%。

关键词：市场份额 studer 成功的原因

The role of soluble sugars during drought in tropical tree seedlings with contrasting tolerances

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Journal of Plant Ecology 2020年第4期13卷 389-397页

作者： Michael J.O’Brien Annabelle Valtat Samuel Abiven Mirjam S.studer Robert Ong Bernhard Schmid Área de Biodiversidad y Conservación Universidad Rey Juan Carlosc/Tulipán s/n.E-28933 MóstolesMadridSpain Southeast Asia Rainforest Research Partnership The Peak VistaLorang Punjak 1Tanjung LipatKota KinabaluSabah 88400Malaysia Department of Evolutionary Biology and Environmental Studies University of ZurichWinterthurerstrasse 1908057 ZurichSwitzerland Department of Geography University of ZurichWinterthurerstrasse 1908057 ZurichSwitzerland Laboratoire de Géologie UMR 8538Ecole Normale SupérieurePSL Research UniversityCNRSParisFrance Centre de recherche enécologie expérimentale et prédictive(CEREEP-Ecotron IleDeFrance) Département de biologieEcole normale supérieureCNRSPSL University77140St-Pierre-les-NemoursFrance Forest Research Centre Sepilok90715 SandakanSabahMalaysia

Aims Non-structural carbohydrates(NSCs)are plant storage compounds used for metabolism,transport,osmoregulation and regrowth following the loss of plant *** in conditions suitable for optimal growth,plants continue to store *** storage may be due to passive accumulation from sink-inhibited growth or active reserves that come at the expense of *** former pathway implies that NSCs may be a by-product of sink limitation,while the latter suggests a functional role of NSCs for use during poor *** Using 13C pulse labelling,we traced the source of soluble sugars in stem and root organs during drought and everwet conditions for seedlings of two tropical tree species that differ in drought tolerance to estimate the relative allocation of NSCs stored prior to drought versus NSCs assimilated during *** monitored growth,stomatal conductance,stem water potential and NSC storage to assess a broad carbon response to *** Findings We found that the drought-sensitive species had reduced growth,conserved NSC concentrations in leaf,stem and root organs and had a larger proportion of soluble sugars in stem and root organs that originated from pre-drought storage relative to seedlings in control *** contrast,the drought-tolerant species maintained growth and stem and root NSC concentrations but had reduced leaf NSCs concentrations with a larger proportion of stem and root soluble sugars originated from freshly assimilated photosynthates relative to control *** results suggest the drought-sensitive species passively accumulated NSCs during water deficit due to growth inhibition,while the drought-tolerant species actively responded to water deficit by allocating NSCs to stem and root *** strategies seem correlated with baseline maximum growth rates,which supports previous research suggesting a trade-off between growth and drought tolerance while providing new evidence for the importance of plasticity in

关键词： ^(13)C labelling carbohydrate storage drought tolerance hydraulic function Shorea parvifolia Shorea beccariana source–sink allocation

上肢周围神经病变:MRI在治疗中的作用及影响

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国际医学放射学杂志 2008年第A6期31卷 514-515页

作者： G.Andreisek D.Burg a.studer D.Weishaupt 成丽娜 Insitute for Diagnostic Radiology Department of Medical Radiology University Hospital Zurich Raemistrasse 1008091 Zurich Switzerland.

探讨MRI在评价上肢周围神经病变中的作用及其对治疗的影响。在1.5T MR设备上,对51例具有桡神经、正中神经和(或)尺神经损伤临床证据。

关键词：周围神经系统周围神经 MRI 上肢

Ⅰ型糖尿病患者变形的手指甲襞毛细血管周围胶原增多的研究

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中国微循环 1993年第1期 2-7页

作者：陈达信 a.studer O.Lütolf T.Schaffner F.Mahler 刘信桥瑞士伯尔尼大学医学院内科血管病实验室

用定量手指甲襞毛细血管显微镜对25例I型糖尿病患者和27例正常人(对照)进行测量,最后的6个病人和7例健康者做手指甲襞活组织检查。体内毛细血管襻宽度作为毛细血管襻变形参数的结果表明,在糖尿病患者其数值明显高于正常人。组织病理检... 详细信息

用定量手指甲襞毛细血管显微镜对25例I型糖尿病患者和27例正常人(对照)进行测量,最后的6个病人和7例健康者做手指甲襞活组织检查。体内毛细血管襻宽度作为毛细血管襻变形参数的结果表明,在糖尿病患者其数值明显高于正常人。组织病理检查表明,糖尿病病人甲襞皮肤乳头胶原沉积明显增加,胶原的沉积与糖尿病患者的甲襞皮肤乳头毛细血管内皮细胞数量和乳头大小相关。由此认为,糖尿病性微血管病,除甲襞毛细血管变形外,胶原沉积可能是代谢紊乱和毛细血管内皮细胞增殖的一个表现。

关键词：手指甲襞毛细血管显微镜甲襞活检毛细血管变形胶原沉积

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Electron-Catalysis

Electron-Catalysis

Practical high-performance lead-free piezoelectrics:structural flexibility beyond utilizing multiphase coexistence

中国化学会第二届全国有机自由基化学会议

作者： SArmido studer Department of Chemistry Westf?lische Wilhelms-University

＜正＞In the lecture the concept of using the electron as a catalyst will be discussed.1,2 It will be shown that the electron is an efficient catalyst for conducting various types of radical cascade reactions that proceed via radical and radical ion intermediates.3 It will be emphasized how a negative charge can significantly weaken the neighbouring C-H bond and activate this bond towards H-atom transfer.3 e,j

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National Science Review 2020年第2期7卷 355-365页

作者： Qing Liu Yichi Zhang Jing Gao Zhen Zhou Dong Yang Kai-Yang Lee Andrew studer Manuel Hinterstein Ke Wang Xiaowen Zhang Longtu Li Jing-Feng Li State Key Laboratory of New Ceramics and Fine Processing School of Materials Science and Engineering Tsinghua University Institute for Applied Materials Karlsruhe Institute of Technology Australian Centre for Neutron Scattering Australian Nuclear Science and Technology Organisation

Due to growing concern for the environment and human health, searching for high-performance lead-free piezoceramics has been a hot topic of scientific and industrial research. Despite the significant progress achieved toward enhancing piezoelectricity, further efforts should be devoted to the synergistic improvement of piezoelectricity and its thermal stability. This study provides new insight into these topics.A new KNN-based lead-free ceramic material is presented, which features a large piezoelectric coefficient(d) exceeding 500 pC/N and a high Curie temperature(T) of ～200℃. The superior piezoelectric response strongly relies on the increased composition-induced structural flexibility due to lattice softening and decreased unit cell distortion. In contrast to piezoelectricity anomalies induced via polymorphic transition, this piezoelectricity enhancement is effective within a broad temperature range rather than a specific small range. In particular, a hierarchical domain architecture composed of nano-sized domains along the submicron domains was detected in this material system, which further contributes to the high piezoelectricity.

关键词： piezoelectricity lead-free potassium–sodium niobite structural flexibility temperature stability