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61.
Ville Merilä 《Results in Mathematics》2009,53(1-2):129-151
62.
Alan R. Katritzky Bushra Agha George Z. de Ville Edward Lunt Michael L. Podmore 《Magnetic resonance in chemistry : MRC》1983,21(11):649-656
13C and 1H NMR spectra and UV spectra are recorded and assigned for a variety of substituted and hetero derivatives of benzo[8,9]quinolizino[4,5,6,7-fed]phenanthrindyliums. Large specific effects of traces of water on these spectra are traced to pseudo-base formation. 相似文献
63.
Alan R. Katritzky George de Ville Ranjan C. Patel Richard Harlow 《Tetrahedron letters》1982,23(12):1241-1242
1-Aryl-2-(2′-benzimidazolyl)-4,6-diphenyl-pyridiniums are converted photochemically into 2-[2′-(1′-arylbenzimidazolyl)]-4,6-diphenylpyridines. X-Ray crystal analysis comfirms the structure for the -chlorophenyl derivative. 相似文献
64.
We investigate how the reduction of the virtual space affects coupled-cluster excitation energies at the approximate singles and doubles coupled-cluster level (CC2). In this reduced-virtual-space (RVS) approach, all virtual orbitals above a certain energy threshold are omitted in the correlation calculation. The effects of the RVS approach are assessed by calculations on the two lowest excitation energies of 11 biochromophores using different sizes of the virtual space. Our set of biochromophores consists of common model systems for the chromophores of the photoactive yellow protein, the green fluorescent protein, and rhodopsin. The RVS calculations show that most of the high-lying virtual orbitals can be neglected without significantly affecting the accuracy of the obtained excitation energies. Omitting all virtual orbitals above 50 eV in the correlation calculation introduces errors in the excitation energies that are smaller than 0.1 eV. By using a RVS energy threshold of 50 eV, the CC2 calculations using triple-ζ basis sets (TZVP) on protonated Schiff base retinal are accelerated by a factor of 6. We demonstrate the applicability of the RVS approach by performing CC2/TZVP calculations on the lowest singlet excitation energy of a rhodopsin model consisting of 165 atoms using RVS thresholds between 20 eV and 120 eV. The calculations on the rhodopsin model show that the RVS errors determined in the gas-phase are a very good approximation to the RVS errors in the protein environment. The RVS approach thus renders purely quantum mechanical treatments of chromophores in protein environments feasible and offers an ab initio alternative to quantum mechanics/molecular mechanics separation schemes. 相似文献
65.
Paavo A. Penttilä Anikó Várnai Manuel Fernández Inkeri Kontro Ville Liljeström Peter Lindner Matti Siika-aho Liisa Viikari Ritva Serimaa 《Cellulose (London, England)》2013,20(3):1031-1040
The hydrolysis of nanofibrillated cellulose (NFC), consisting of individual cellulose fibrils, was followed using small-angle scattering techniques in order to reveal changes in the substrate structure caused by cellulose degrading enzymes. In particular, the nanoscale structure of the network of cellulose fibrils was characterized with the combination of small-angle neutron scattering and small-angle x-ray scattering. In the nanocellulose with higher xylan content, the interfibrillar distance was shown to remain unchanged during enzymatic degradation, whereas the distance increased in the nanocellulose with lower xylan content. The limiting effect of xylan on the hydrolysis and a faster hydrolysis of the more thoroughly fibrillated segments of the NFC network could be observed. Despite the extensive fibrillation of the raw material, however, the hydrolysis was eventually limited by the aggregated and heterogeneous structure of the substrate. 相似文献
66.
Lab‐on‐a‐Chip Reactor Imaging with Unprecedented Chemical Resolution by Hadamard‐Encoded Remote Detection NMR 下载免费PDF全文
Dr. Ville‐Veikko Telkki Dr. Vladimir V. Zhivonitko M. Sc. Anne Selent Dr. Gianmario Scotti M. Sc. Jarmo Leppäniemi Prof. Sami Franssila Prof. Igor V. Koptyug 《Angewandte Chemie (International ed. in English)》2014,53(42):11289-11293
The development of microfluidic processes requires information‐rich detection methods. Here we introduce the concept of remote detection exchange NMR spectroscopy (RD‐EXSY), and show that, along with indirect spatial information extracted from time‐of‐flight data, it provides unique information about the active regions, reaction pathways, and intermediate products in a lab‐on‐a‐chip reactor. Furthermore, we demonstrate that direct spatial resolution can be added to RD‐EXSY efficiently by applying the principles of Hadamard spectroscopy. 相似文献
67.
Auerbach H. Friedenthal J. Ville E. Derrien A. Herrmann V. Ducceschi E. Buchner Sigward Mitscherlich M. Bial P. Mayer Brat E. C. van Leersum B. Reinbold O. Amrein J. Ostori E. Riegler H. L. Visser Jos Bilinski H. Held A. Berg Rud Ofner C. Neuberg O. Wentzki O. Folin und H. Bellocq 《Fresenius' Journal of Analytical Chemistry》1905,44(6-7):455-459
Ohne Zusammenfassung 相似文献
68.
Bobin George Abraham Ville Santala Nikolai V. Tkachenko Matti Karp 《Analytical and bioanalytical chemistry》2014,406(28):7195-7204
Monitoring of intracellular redox status in a bacterial cell provides vital information about the physiological status of the cell, which can be exploited in several applications such as metabolic engineering and computational modeling. Fluorescent protein-based genetically encoded sensors can be used to monitor intracellular oxidation/reduction status. This study reports the development of a redox sensor for intracellular measurements using fluorescent protein pairs and the phenomenon of Förster resonance energy transfer (FRET). For the development of the sensor, fluorescent proteins Citrine and Cerulean were genetically modified to carry reactive cysteine residues on the protein surface close to the chromophore and a constructed FRET pair was fused using a biotinylation domain as a linker. In oxidized state, the FRET pairs are in close proximity by labile disulfide bond formation resulting in higher FRET efficiency. In reducing environment, the FRET is diminished due to the increased distance between FRET pairs providing large dynamic measurement range to the sensor. Intracellular studies in Escherichia coli mutants revealed the capability of the sensor in detecting real-time redox variations at single cell level. The results were validated by intensity based and time resolved measurements. The functional immobilization of the fluorescent protein-based FRET sensor at solid surfaces for in vitro applications was also demonstrated. Graphical Abstract
69.
We establish the sharp Gårding inequality on compact Lie groups. The positivity condition is expressed in the non-commutative phase space in terms of the full matrix symbol, which is defined using the representations of the group. Applications are given to the L2 and Sobolev boundedness of pseudo-differential operators. 相似文献
70.
Luca Marzola Antonio Racioppi Ville Vaskonen 《The European Physical Journal C - Particles and Fields》2017,77(7):484
Thermal corrections in classically conformal models typically induce a strong first-order electroweak phase transition, thereby resulting in a stochastic gravitational background that could be detectable at gravitational wave observatories. After reviewing the basics of classically conformal scenarios, in this paper we investigate the phase transition dynamics in a thermal environment and the related gravitational wave phenomenology within the framework of scalar conformal extensions of the Standard Model. We find that minimal extensions involving only one additional scalar field struggle to reproduce the correct phase transition dynamics once thermal corrections are accounted for. Next-to-minimal models, instead, yield the desired electroweak symmetry breaking and typically result in a very strong gravitational wave signal. 相似文献