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1.
Nielsen MB Moonen NN Boudon C Gisselbrecht JP Seiler P Gross M Diederich F 《Chemical communications (Cambridge, England)》2001,(18):1848-1849
Novel extended tetrathiafulvalenes (TTFs) with hexa-2,4-diyne-1,6-diylidene spacers between the two 1,3-dithiole rings and laterally appended alkynyl moieties for one- and two-dimensional scaffolding were synthesised and investigated for their electronic properties. 相似文献
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The oxidation kinetics of ethanol by Ce(IV) has been studied as a function of pH, nitrate and water concentration. Even at high concentration of H+ and NO
3
–
several species appear to exist. The oxidation is fastest in strongly acidic medium without added nitrate ions.
Ce(IV) pH, . H+ NO 3 – , Ce(IV). .相似文献
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Alan Rigter Jan PM Langeveld Drophatie Timmers-Parohi Jorg G Jacobs Peter LJM Moonen Alex Bossers 《BMC biochemistry》2007,8(1):6
Background
The common event in transmissible spongiform encephalopathies (TSEs) or prion diseases is the conversion of host-encoded protease sensitive cellular prion protein (PrPC) into strain dependent isoforms of scrapie associated protease resistant isoform (PrPSc) of prion protein (PrP). These processes are determined by similarities as well as strain dependent variations in the PrP structure. Selective self-interaction between PrP molecules is the most probable basis for initiation of these processes, potentially influenced by chaperone molecules, however the mechanisms behind these processes are far from understood. We previously determined that polymorphisms do not affect initial PrPC to PrPSc binding but rather modulate a subsequent step in the conversion process. Determining possible sites of self-interaction could elucidate which amino acid(s) or amino acid sequences contribute to binding and further conversion into other isoforms. To this end, ovine – and bovine PrP peptide-arrays consisting of 15-mer overlapping peptides were probed with recombinant sheep PrPC fused to maltose binding protein (MBP-PrP). 相似文献4.
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Dieltiens N Moonen K Stevens CV 《Chemistry (Weinheim an der Bergstrasse, Germany)》2007,13(1):203-214
A new tandem reaction sequence has been developed for the synthesis of 2-phosphono pyrroles. The sequence consists of ring-closing enyne metathesis of a substituted aminophosphonate, containing a terminal alkyne and an internal alkene, in combination with in situ oxidation of the produced 3-pyrrolines using tetrachloroquinone. By analyzing the formation of the end and certain byproducts, taking into account the difference in reactivity of different substrates and carefully studying spectroscopic data, it was found that the reaction proceeds by means of the "yne-then-ene" pathway. During the initiation phase, a new ruthenium carbene is formed which continues the propagation cycle. 相似文献
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Computer simulations based on Discrete Element Method have been performed in order to investigate the influence of interparticle interactions on the kinetics of self-assembly and the mechanical strength of nanoparticle aggregates.Three different systems have been considered.In the first system the interaction between particles has been simulated using the JKR (Johnson,Kendall and Roberts) contact theory,while in the second and third systems the interaction between particles has been simulated using van der Waals and electrostatic forces respectively.In order to compare the mechanical behaviour of the three systems,the magnitude of the maximum attractive force between particles has been kept the same in all cases.However,the relationship between force and separation distance differs from case to case and thus,the range of the interparticle force.The results clearly indicate that as the range of the interparticle force increases,the self-assembly process is faster and the work required to produce the mechanical failure of the assemblies increases by more than one order of magnitude. 相似文献
9.
The structure factor of a concentrated colloidal suspension is an important means in the characterization of the interaction forces between the colloidal particles. It can, in principle, be determined with small angle x-ray scattering. To avoid unacceptably long measuring times, one has to use a high power x-ray source or a slit collimation camera. The first is not readily accessible because of the very high costs. The latter is available in many laboratories, but here the fundamental information is contained in the data in a complicated way. A so-called desmearing operation is needed to reveal this information. Because of the different experimental errors and their sensitivity to the desmearing, the accuracy of the structure factor will be rather limited. In this paper we simulate the experimental errors separately to check their influence in combination with the desmearing.Although the overall accuracy is limited some important features can be determined. The value atK=0 and thus the osmotic compressibility can be calculated, and the position and the height of the first maximum in the structure factor are quite reliable too. This gives some insight in the type of interaction and the influence of polydispersity.Special attention should be given to the determination of the form factor by using extra long measuring times for the very diluted sample, this will improve the overall accurary. 相似文献
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在一系列H模放电条件下,建立了一个旨在研究等离子体温度分布剖面不变性的数据库。介绍了数据库建立过程中要解决的关键问题和所用软件,对等离子体温度分布剖面不变性及芯部约束与边缘参数的关系进行了研究。 相似文献