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1.
Herman Winick 《Synchrotron Radiation News》2015,28(4):26-27
I am indebted to Karl Brown for suggesting that I invite Klaus, who I did not know at the time, to a workshop on wiggler magnets in March 1977. I recall Karl saying to me something like, “Herman, if you want someone who knows about magnets, you should invite Klaus Halbach.” Klaus came and even made a contribution about some aspects of the design of electromagnet wigglers, the only type of wigglers that had been considered to that time. However, it was at that workshop that Klaus got his introduction to synchrotron radiation, mostly by listening to talks by Albert Hofmann and Andy Sesler, who explained the marvelous properties of undulator magnets as radiation sources. Klaus filed this information in his long-term memory banks while working on other topics, particularly the design of permanent magnet quadrupoles for proton linacs. 相似文献
2.
Pieter Bouckenooge Oliver Bauer Kathrin Eckhard Herman Terryn 《Surface and interface analysis : SIA》2020,52(4):174-184
In this paper, the behaviour of the industrial applied Ti/Zr conversion coating (CC) pretreatment on rolled automotive aluminium samples (AA5182) is analysed. Due to its nanometre lateral and depth resolution, Auger electron spectroscopy (AES) is used to analyse the CC distribution at surface cathodic intermetallic particles. As a result of its high surface sensitivity, the AES technique is very susceptible to differences in the top contamination layer thickness. It is demonstrated that AES point measurements performed on aluminium model samples coated with 1.5 and 3 nm of Ti (oxide) layer cannot differentiate the two-layer thicknesses if a difference in the top contamination thickness is not taken into account. A data analysis methodology is introduced, based on the ratio of normalized peak areas (enrichment ratios), to eliminate the effect of the contamination layer thickness. The experimental validation of the methodology is performed on the model samples, demonstrating errors of 2% on the enrichment ratios on similar samples with different contamination layer thicknesses, while the conventional spectra quantification results in errors of 49%. The methodology is also theoretically substantiated within certain constraints. By the use of the AES methodology, an enriched Ti and Zr deposition is confirmed at the cathodic intermetallic particles at the surface of the industrial no-rinse CC sprayed automotive aluminium sheet samples. 相似文献
3.
Ying Yu Hao Xing Zhicong Zhou Junkai Liu Herman H-YSung Ian D.Williams Jonathan E.Halpert Zheng Zhao Ben Zhong Tang 《中国科学:化学(英文版)》2022,65(1):135-144
Molecular interactions are crucial in diverse fields of protein folding,material science,nanotechnology,and life origins.Although mounting experimental research controls luminescent behavior by adjusting molecular interactions in light-emitting materials,it remains elusive to correlate microscopic molecular interactions with macroscopic luminescent behavior directly.Here,we synthesized three red luminogens with subtle structural variation and investigated the influence of molecular interactions on their luminescent behavior in solution and aggregate states.Our results indicate that strongπ-πand D-A interactions in both dilute solution(between luminogen and solvent molecules)and aggregate(between luminogens)states cause the redshift in emission,while weak interactions(e.g.,Van der Waals,C–H…π,and C–H…F interactions)enhance the quantum yield.This work provides a thoughtful investigation into the complicated influence of various molecular interactions on luminescent behavior. 相似文献
4.
Bob Boyd Gareth Brenton Eddie Clayton Jonathan Curtis R. M. Elliott G. A. Errock B. N. Green R. H. Bateman Simon J. Gaskell Iwan Griffiths Zdenek Herman Philip Jonathan Rich Kondrat Mila Laušević Chris Lock Deepak Mathur John F. J. Todd Károly Vékey 《Rapid communications in mass spectrometry : RCM》2016,30(11):1253-1264
5.
Dr. Wei Wei Ka Key Cheung Dr. Ran Lin Lam Cheung Kong Ka Lok Chan Dr. Herman H. Y. Sung Prof. Dr. Ian D. Williams Prof. Dr. Rongbiao Tong Prof. Dr. Zhenyang Lin Prof. Dr. Guochen Jia 《Angewandte Chemie (International ed. in English)》2023,62(36):e202307251
A unique benzannulation strategy for regioselective de novo synthesis of densely functionalized phenols is described. Through metal-mediated formal [2+2+1+1] cycloaddition of two different alkynes and two molecules of CO, a series of densely functionalized phenols were obtained. The benzannulation strategy allows efficient regioselective installation up to five different substituents on a phenol ring. The resulting phenols have a substitution pattern different from those obtained from Dötz and Danheiser benzannulations. 相似文献
6.
Comparing Cyclophellitol N‐Alkyl and N‐Acyl Cyclophellitol Aziridines as Activity‐Based Glycosidase Probes 下载免费PDF全文
Jianbing Jiang Thomas J. M. Beenakker Dr. Wouter W. Kallemeijn Prof. Dr. Gijsbert A. van der Marel Hans van den Elst Dr. Jeroen D. C. Codée Prof. Dr. Johannes M. F. G. Aerts Prof. Dr. Herman S. Overkleeft 《Chemistry (Weinheim an der Bergstrasse, Germany)》2015,21(30):10861-10869
The synthesis and evaluation as activity‐based probes (ABPs) of three configurationally distinct, fluorescent N‐alkyl cyclophellitol aziridine isosteres for profiling GH1 β‐glucosidase (GBA), GH27 α‐galactosidase (GLA) and GH29 α‐fucosidase (FUCA) is described. In comparison with the corresponding acyl aziridine ABPs reported previously, the alkyl aziridine ABPs are synthesized easily and are more stable in mild acidic and basic media, and are thus easier to handle. The β‐glucose‐configured alkyl aziridine ABP proves equally effective in labeling GBA as its N‐acyl counterpart, whereas the N‐acyl aziridines targeting GLA and FUCA outperform their N‐alkyl counterparts. Alkyl aziridines can therefore be an attractive alternative in retaining glycosidase ABP design, but in targeting a new retaining glycosidase both N‐alkyl and N‐acyl aziridines are best considered at the onset of a new study. 相似文献
7.
Hua-Hua Wang Yi-Yu Jiang Mian HR Mahmood Hai-Yang Liu Herman H.Y. Sung Ian D. Williams Chi K. Chang 《中国化学快报》2015,26(5):529-533
Tetrakis(alloxycarbonyl)porphyrin and its β-octafluoro-substituted derivatives were synthesized via Lindsey method and transformed to their zinc complexes.Single crystal X-ray structures of corresponding Zn(Ⅱ) porphyrins revealed that β-octafluorination will give more compactness of porphyrin moieties in the crystal structure owing to the hydrogen bonding interactions involving β-fluorine atoms.An unusual six-coordinated Zn(Ⅱ) was found via intramolecular coordination of oxygen atom of meso-substituents with central Zn(Ⅱ). 相似文献
8.
Ekaterina E. Stoikova Michail I. Sorvin Dmitry N. Shurpik Herman C. Budnikov Ivan I. Stoikov Gennady A. Evtugyn 《Electroanalysis》2015,27(2):440-449
A novel potentiometric sensor based on screen‐printed carbon electrode covered with electropolymerized polyaniline (PANI) and unsubstituted pillar[5]arene as ionophore has been developed and tested in potentiometric measurements of pH and metal ions. The introduction of pillar[5]arene improved the reversibility of the pH response in the range from 2.0 to 9.0 with the slope of 45 mV/pH. Among metal cations, the response to Fe3+ and Ag+ ions was referred to PANI redox conversion whereas the signal toward Cu2+ in the range from 1.0×10?6 to 1.0×10?2 M (limit of detection (LOD) 3.0×10?7 M) to specific interaction with the macrocycle. 相似文献
9.
10.
Experimental visualization of bubble formation from an orifice in microgravity in the presence of electric fields 总被引:4,自引:0,他引:4
The formation of air bubbles injected into a stagnant, isothermal liquid in microgravity through an orifice was studied.
The bubbles grew very large in microgravity. They attained a nearly spherical shape and showed pronounced affinity towards
coalescence in the absence of electric fields and other perturbations. Under the influence of electric fields, periodic detachment
was observed, with bubble sizes larger than in terrestrial conditions. The bubble shape was elongated. After detachment, the
bubbles moved away from the electrode at which they formed without coalescing with other bubbles. Experimental data on bubble
shape and size at detachment showed good agreement with models.
Received: 26 March 2001 / Accepted: 16 August 2001 相似文献