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121.
Dr. Krzysztof B. Beć Dr. Justyna Grabska Prof. Christian W. Huck 《Chemistry (Weinheim an der Bergstrasse, Germany)》2021,27(5):1514-1532
This review article focuses on the principles and applications of miniaturized near-infrared (NIR) spectrometers. This technology and its applicability has advanced considerably over the last few years and revolutionized several fields of application. What is particularly remarkable is that the applications have a distinctly diverse nature, ranging from agriculture and the food sector, through to materials science, industry and environmental studies. Unlike a rather uniform design of a mature benchtop FTNIR spectrometer, miniaturized instruments employ diverse technological solutions, which have an impact on their operational characteristics. Continuous progress leads to new instruments appearing on the market. The current focus in analytical NIR spectroscopy is on the evaluation of the devices and associated methods, and to systematic characterization of their performance profiles. 相似文献
122.
R. Menegazzo P. Kleinheinz R. Collatz H. Güven J. Styczen D. Schardt H. Keller O. Klepper G. Walter A. Huck G. Marguier J. Blomqvist 《Zeitschrift für Physik A Hadrons and Nuclei》1994,349(1):13-24
A high-sensitivityγ-spectroscopic study of the149Hoπh 11/2 andπs 1/2 β-decays using mass separated sources has located dominant 0+ → 1+ GT decay strength associated with decay of pairedh 11/2 protons, leading to 3п-states in the149Dy daughter nucleus. In theirγ-decay low-lying149Dy levels characteristic of anN=83 nucleus are excited. They include theνf 7/2,νp 3/2,νh 9/2 andνp 1/2 single particle- and theνs 1 2/?1 andνd 3 2/?1 two-particle one-hole states, as well as the νf 7/2 × 3? andνf 7/2 × 2+ particle-phonon multiplets. A synopsis is given of these excitations in theN=83 isotones from149Nd to153Yb. The149Dy GT decay strength is discussed in terms of the147Tb82 and148Dy82 decays. The strength function results are also compared with independent149Ho 11/2? decay data from the literature based on totalγ-ray absorption measurements. 相似文献
123.
The title compound undergoes efficient photoaddition of a molecule of a hydroxylic solvent (H(2)O, MeOH, (Me)(2)CHOH) across the 9- and 10-positions of the anthracene moiety to give isolable triphenylmethanol or triphenylmethyl ether type products. The reaction is believed to proceed via a mechanism involving water-mediated formal excited state intramolecular proton transfer (ESIPT) from the phenolic OH to the 10-position of the anthracene ring, generating an o-quinone methide intermediate that is observable by nanosecond laser flash photolysis, and is trappable with nucleophiles. A "water-relay" mechanism for proton transfer seems plausible but cannot be proven directly with the data available. Irradiation in deuterated solvents led to incorporation of one deuterium atom at the methylene position in the photoaddition product, and partial deuterium exchange of the 10-position of recovered starting material, consistent with the proposed formal excited state proton transfer mechanism. The deuterium exchange and photoaddition reach maximum quantum efficiency at approximately 5 M water (in CH(3)CN or CH(3)OH), with no reaction observed in the absence of a hydroxylic solvent, demonstrating the sensitivity of this type of ESIPT to solvent composition. 相似文献
124.
Katalin Böddi Anikó Takátsy Szilvia Szabó Lajos Markó László Márk István Wittmann Róbert Ohmacht Gergely Montskó Rainer M. Vallant Thomas Ringer Rania Bakry Christian W. Huck Günther K. Bonn Zoltán Szabó 《Journal of separation science》2009,32(2):295-308
SPE plays a crucial role in bioanalytical research. In the present work a novel fullerene(C60)‐derivatised silica material is compared with octadecyl(C18) – and triaconthyl(C30)‐silicas regarding recoveries of peptides and sequence coverage of HSA and fibrinogen digests. C30‐ and C60(30 nm)‐SPE materials were found to be the two most prominent SPE materials. At low peptide concentrations C60‐material prepared from a silica gel with a pore size of 30 nm has proven to be the best material with regards to recoveries. By increasing the amount of loaded peptides recoveries decrease due to its relative low binding capacity in contrast to C30‐silica particles, showing no changes. The best sequence coverages of Aα‐ and Bβ‐chains of 20 pmol fibrinogen digest can also be achieved using these two SPE materials, C60 (30 nm) demonstrates an outstanding value of sequence coverage (62.15%) achieved for the γ‐chain. After nonenzymatic glycation the digests of fibrinogen and HSA were also separated. This makes the detection of a considerably higher number of glycated peptides possible compared to the unfractionated digests and the use of boronate affinity chromatography in the case of fibrinogen. For HSA, ten new sites of glycation at lysine and arginine residues have been explored. Using the detailed SPE/off‐line MALDI method the glycation sites on fibrinogen are first described in this paper. 相似文献
125.
A. Jokinen M. Oinonen J. Äystö P. Baumann P. Dendooven F. Didierjean V. Fedoseyev A. Huck Y. Jading A. Knipper M. Koizumi U. Köster J. Lettry P.O. Lipas W. Liu V. Mishin M. Ramdhane H. Ravn E. Roeckl V. Sebastian G. Walter 《The European Physical Journal A - Hadrons and Nuclei》1998,3(3):271-276
Beta decay of 58Zn has been studied for the first time. A new laser ion-source concept has been used to produce mass-separated sources for
beta and gamma spectroscopy. The half-life of 58Zn was determined to be 86(18) ms. Comparisons are made with previous data from charge-exchange reactions. Our Gamow–Teller
strength to the 1+ state at 1051 keV excitation in 58Cu agrees well with the value extracted from a recent (3He, t) study. Extensive shell-model calculations are presented.
Received: 5 June 1998 / Revised version: 24 July 1998 相似文献
126.
Dr. Chang‐Nim Im Dr. Nam‐Young Kang Dr. Hyung‐Ho Ha Dr. Xuezhi Bi Dr. Jae Jung Lee Dr. Sung‐Jin Park Dr. Sang Yeon Lee Dr. Marc Vendrell Dr. Yun Kyung Kim Dr. Jun‐Seok Lee Dr. Jun Li Dr. Young‐Hoon Ahn Dr. Bo Feng Dr. Huck‐Hui Ng Dr. Seong‐Wook Yun Prof. Dr. Young‐Tae Chang 《Angewandte Chemie (International ed. in English)》2010,49(41):7497-7500
127.
Mattle Christian Heigl Nico Abel Gudrun Bonn Günther K. Huck Christian W. 《平面色谱法杂志一现代薄层色谱法》2010,23(5):348-352
JPC – Journal of Planar Chromatography – Modern TLC - By use of near infrared (NIR) spectroscopy hyphenated to thinlayer chromatography (TLC) for analysis of methoxylated flavones in a... 相似文献
128.
Kohn P Huettner S Komber H Senkovskyy V Tkachov R Kiriy A Friend RH Steiner U Huck WT Sommer JU Sommer M 《Journal of the American Chemical Society》2012,134(10):4790-4805
Identifying structure formation in semicrystalline conjugated polymers is the fundamental basis to understand electronic processes in these materials. Although correlations between physical properties, structure formation, and device parameters of regioregular, semicrystalline poly(3-hexylthiophene) (P3HT) have been established, it has remained difficult to disentangle the influence of regioregularity, polydispersity, and molecular weight. Here we show that the most commonly used synthetic protocol for the synthesis of P3HT, the living Kumada catalyst transfer polycondensation (KCTP) with Ni(dppp)Cl(2) as the catalyst, leads to regioregular chains with one single tail-to-tail (TT) defect distributed over the whole chain, in contrast to the hitherto assumed exclusive location at the chain end. NMR end-group analysis and simulations are used to quantify this effect. A series of entirely defect-free P3HT materials with different molecular weights is synthesized via new, soluble nickel initiators. Data on structure formation in defect-free P3HT, as elucidated by various calorimetric and scattering experiments, allow the development of a simple model for estimating the degree of crystallinity. We find very good agreement for predicted and experimentally determined degrees of crystallinities as high as ~70%. For Ni(dppp)Cl(2)-initiated chains comprising one distributed TT unit, the comparison of simulated crystallinities with calorimetric and optical measurements strongly suggests incorporation of the TT unit into the crystal lattice, which is accompanied by an increase in backbone torsion. Polydispersity is identified as a major parameter determining crystallinity within the molecular weight range investigated. We believe that the presented approach and results not only contribute to understanding structure formation in P3HT but are generally applicable to other semicrystalline conjugated polymers as well. 相似文献
129.
130.