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排序方式: 共有360条查询结果,搜索用时 15 毫秒
71.
This paper reviews the character sets used in today's computer systems and discusses character sets for future computer systems. Some newer Latin-based character sets are introduced and compared in terms of their suitability for information interchange and information processing. Finally, the character set most appropriate for use in future computer systems is suggested. 相似文献
72.
Structure–Activity Relationship Studies on (R)‐PFI‐2 Analogues as Inhibitors of Histone Lysine Methyltransferase SETD7
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Danny C. Lenstra Dr. Eddy Damen Dr. Ruben G. G. Leenders Dr. Richard H. Blaauw Prof. Dr. Floris P. J. T. Rutjes Dr. Anita Wegert Dr. Jasmin Mecinović 《ChemMedChem》2018,13(14):1405-1413
SETD7 is a histone H3K4 lysine methyltransferase involved in human gene regulation. Aberrant expression of SETD7 has been associated with various diseases, including cancer. Therefore, SETD7 is considered a good target for the development of new epigenetic drugs. To date, few selective small‐molecule inhibitors have been reported that target SETD7, the most potent being (R)‐PFI‐2. Herein we report structure–activity relationship studies on (R)‐PFI‐2 and its analogues. A library of 29 structural analogues of (R)‐PFI‐2 was synthesized and evaluated for inhibition of recombinantly expressed human SETD7. The key interactions were found to be a salt bridge and a hydrogen bond formed between (R)‐PFI‐2′s NH2+ group and SETD7′s Asp256 and His252 residue, respectively. 相似文献
73.
Masaaki Kitano Ryo Mitsui Diana Rakhmawaty Eddy Zeinhom M. A. El-Bahy Masaya Matsuoka Michio Ueshima Masakazu Anpo 《Catalysis Letters》2007,119(3-4):217-221
Nanowire TiO2 thin films were successfully prepared on Ti metal substrates by hydrothermal treatment of calcined Ti foils in 10 M NaOH.
The nanowire TiO2 thin films exhibited much larger surface area and higher photoelectrochemical performance than the TiO2 thin films prepared on Ti metal substrates by the calcination of Ti foil. These nanowire films were shown to act as an efficient
photoanodes for the photoelectrochemical water splitting reaction. 相似文献
74.
A good simulation model for paper machines can be used to identify deficiencies in the design, bottlenecks during operation, and regions of poor control. It also allows users to test their hypotheses and innovations without potentially causing major upsets and reducing throughput. In this work, a dynamic model of the wet end system has been developed using the IDEASTM platform, describing the distribution of fines, fillers and fibres throughout the system. The model was then tested at steady state with mill data for the low‐ash and high‐ash production grades, and the results show that over 70% of the predicted values had only 5% deviation. The dynamic simulation was also used to show that the retention aid controller would react in the wrong direction due to changes in the wire pit consistency and the stock ratio would cause major changes in stream compositions and consistencies of the wet end. 相似文献
75.
76.
Hélène Lotz Charly Carrière Christian Bataillon Emmanuel Gardes Isabelle Monnet Eddy Foy Michel L. Schlegel James J. Dynes Delphine Neff Florence Mercier-Bion Philippe Dillmann 《工业材料与腐蚀》2021,72(1-2):120-130
Corrosion experiments were performed on two metallic substrates, a ferritic–pearlitic steel (P285NH) and a ferritic one (Armco), in silicate environment during 30 days at 120°C. Corrosion products were characterized in terms of morphology (scanning electron microscope and transmission electron microscopy), composition (energydispersive X-ray spectroscopy) and structure (µ-Raman, selected area electron diffraction, X-ray absorption near edge structure). Results show a nanometric inner layer made of compact and adherent nanocrystallized magnetite with, locally a thickness up to several micrometers due to the metal microstructure. An outer layer of Fe-rich phyllosilicate, smectite and serpentine, more porous than the inner one and poorly adherent is observed around both the samples. 相似文献
77.
Eno E. Ebenso David A. Isabirye Nnabuk O. Eddy 《International journal of molecular sciences》2010,11(6):2473-2498
Three thiosemicarbazides, namely 2-(2-aminophenyl)-N phenylhydrazinecarbothioamide (AP4PT), N,2-diphenylhydrazinecarbothioamide (D4PT) and 2-(2-hydroxyphenyl)-N-phenyl hydrazinecarbothioamide (HP4PT), were investigated as corrosion inhibitors for mild steel in H2SO4 solution using gravimetric and gasometric methods. The results revealed that they all inhibit corrosion and their % inhibition efficiencies (%IE) follow the order: AP4PT > HP4PT > D4PT. The %IE obtained from the gravimetric and gasometric experiments were in good agreement. The thermodynamic parameters obtained support a physical adsorption mechanism and the adsorption followed the Langmuir adsorption isotherm. Some quantum chemical parameters were calculated using different methods and correlated with the experimental %IE. Quantitative structure activity relationship (QSAR) approach was used on a composite index of some quantum chemical parameters to characterize the inhibition performance of the studied molecules. The results showed that the %IE were closely related to some of the quantum chemical parameters, but with varying degrees. The calculated/theoretical %IE of the molecules were found to be close to their experimental %IE. The local reactivity has been studied through the Fukui and condensed softness indices in order to predict both the reactive centers and to know the possible sites of nucleophilic and electrophilic attacks. 相似文献
78.
This paper presents a simulation methodology to analyze hydronic heat distribution systems in a fast and user friendly way. As suggested in its name, the “Base Circuit Methodology” (BCM) is based on the observation that thermo-hydronic networks can be built up as a modular composition of elementary “Base Circuits” (BCs). Once the hydronic and thermodynamic behavior of such basic components is described in a set of dedicated equations, complex thermal distribution networks can easily be modeled by connecting the basic sub models. In addition to control performance simulations (accuracy, stability, speed) the BCM puts extra effort into energy efficiency analysis. In fact, every BC is a local sub unit in which heat flows are gathered, divided or changed in terms of temperature and/or flow. Therefore the BCM model setup yields the opportunity to analyze the net heat transport and its adaptations while crossing the network. Doing so, system designers get the efficiency variables more structured, leading to straightforward abilities to optimize heat and cold distribution. Practical examples prove the benefits of the methodology. Moreover, a test installation was built in which flows, pressures, and temperatures are confronted with the simulation results. The simulations are processed by means of the iterative equation solver EES (Engineering Equation Solver; ©F-chart) which has been experienced as a very compliant software package. As a result the methodology is delivered as a validated and open source library. 相似文献
79.
Heather Kirk Klaas Vrieling Eddy Van Der Meijden Peter G. L. Klinkhamer 《Journal of chemical ecology》2010,36(4):378-387
We examined the effects of water and nutrient availability on the expression of the defense pyrrolizidine alkaloids (PAs)
in Senecio jacobaea and S. aquaticus. Senecio jacobaea, and S. aquaticus are adapted to different natural habitats, characterized by differing abiotic conditions and different selection pressures
from natural enemies. We tested if PA concentration and diversity are plastic over a range of water and nutrient treatments,
and also whether such plasticity is dependent on plant species. We also tested the hypothesis that hybridization may contribute
to PA diversity within plants, by comparing PA expression in parental species to that in artificially generated F1 hybrids, and also in later generation natural hybrids between S. jacobaea and S. aquaticus. We showed that total PA concentration in roots and shoots is not dependent on species, but that species determines the pattern
of PA diversification. Pyrrolizidine alkaloid diversity and concentration are both dependent on environmental factors. Hybrids
produce a putatively novel PA, and this PA is conserved in natural hybrids, that are backcrossed to S. jacobaea. Natural hybrids that are backcrossed several times to S. jacobaea are with regard to PA diversity significantly different from S. jacobaea but not from S. aquaticus, while F1 hybrids are in all cases more similar to S. jacobaea. These results collectively suggest that PA diversity is under the influence of natural selection. 相似文献
80.
Nevejans D Neefs E Van Ransbeeck E Berkenbosch S Clairquin R De Vos L Moelans W Glorieux S Baeke A Korablev O Vinogradov I Kalinnikov Y Bach B Dubois JP Villard E 《Applied optics》2006,45(21):5191-5206
A new compact spaceborne high-resolution spectrometer developed for the European Space Agency's Venus Express spacecraft is described. It operates in the IR wavelength range of 2.2 to 4.3 microm and measures absorption spectra of minor constituents in the Venusian atmosphere. It uses a novel echelle grating with a groove density of 4 lines/mm in a Littrow configuration in combination with an IR acousto-optic tunable filter for order sorting and an actively cooled HgCdTe focal plane array of 256 by 320 pixels. It is designed to obtain an instrument line profile of 0.2 cm(-1). First results on optical and spectral properties are reported. 相似文献