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51.
G. Glas Rudolf Gompper M. Junius R. Mertz H.-U. Wagner Heinrich Nth M. Staudigl 《Advanced Synthesis \u0026amp; Catalysis》1990,332(6):949-967
Donor Substituted 2,4-Diazacyclopentadienones and Indigoid 1,3,5,7-Tetraazafulvalenes Hydrolysis of tris(diethylamino)imidazolylium chloride gives rise to 2,5-bis-diethyl-amino-4H-imidazolin-4-one; thiolysis leads, depending on conditions, to 2,5-bis-diethylamino-4H-imidazolin-4-thione or potassium 2,6-bis-diethylamino-1,3,5,7-tetraazafulvalene-4,8-dithiolate. The latter can be protonated to form green 2,6-bis(dimethylamino)-3,4,7,8-tetrahydro-1,3,5,7-tetraaza-fulvalen-4,8-dithione, a new indigoid compound, and alkylated to give blue 2,6-bis-diethylamino-4,8-bis-alkylthio-1,3,5,7-tetraazafulvalenes. Treatment of 2,5-bis-diethylamino-4H-imidazolin-4-thione with copper furnishes 2,6,4,8-tetrakis-diethylamino-1,3,5,7-tetraazafulvalene. – Oxidation of 2,6-bis-dimethylamino-3,4,7,8-tetrahydro-1,3,5,7-tetraazafulvalen-4,8-dithione gives rise to (2,2′-bis-diethylamino-4,4′-bi(4H-imidazol)-5,5′-dithione, corresponding to dehydroindigo, and reduction leads to a colorless compound, corresponding to leucoindigo. 相似文献
52.
Marcus Conrad Christian A. Sldner Heinrich Sticht 《International journal of molecular sciences》2022,23(3)
The histamine H1 receptor (H1R) is a G protein-coupled receptor (GPCR) and represents a main target in the treatment of allergic reactions as well as inflammatory reactions and depressions. Although the overall effect of antagonists on H1 function has been extensively investigated, rather little is known about the potential modulatory effect of ions or sequence variants on antagonist binding. We investigated the dynamics of a phosphate ion present in the crystal structure and of a sodium ion, for which we determined the position in the allosteric pocket by metadynamics simulations. Both types of ions exhibit significant dynamics within their binding site; however, some key contacts remain stable over the simulation time, which might be exploited to develop more potent drugs targeting these sites. The dynamics of the ions is almost unaffected by the presence or absence of doxepin, as also reflected in their small effect (less than 1 kcal·mol−1) on doxepin binding affinity. We also examined the effect of four H1R sequence variants observed in the human population on doxepin binding. These variants cause a reduction in doxepin affinity of up to 2.5 kcal·mol−1, indicating that personalized medical treatments that take into account individual mutation patterns could increase precision in the dosage of GPCR-targeting drugs. 相似文献
53.
The structure and quantity of phenols, occurring in two different roasted Robusta coffees and in four samples of roast coffee, were investigated. Identification and quantification were carried out after special extraction procedures and clean-up methods by gas chromatography/mass spectrometry. The quantities of 35 phenols investigated ranged from below 0.1 mg/kg to more than 1000 mg/kg. Sixteen phenols were identified in coffee for the first time. 相似文献
54.
T.Stegmaier V.von Amim M.Linke M.Milwich J.Sarsour A.Scherrieble P.Schneider H.Planck 戴自怡 《国际纺织导报》2007,35(6):10-12,14
纤维基技术的应用对仿生学的成功发展呈现出巨大的潜力,因为宇宙成物在生长过程、多毛结构和增强纤维方面具有许多相似性.约七年前,邓肯道夫纺织技术与工艺研究所协同众位生物学家一起开创了仿生学的研发,至今方兴未艾. 相似文献
55.
在AiF研究项目的(AiF编号:14315)的范围内,通过在邓肯道夫纺织工艺研究所(ITV)对锭子的开发,即应用旋转纱线制动装置和经过优化的钢领钢丝圈系统,研究了改善加工化学纤维的环锭纺设备的性能的可能性. 相似文献
56.
第1部分介绍了浸轧染色的印花头梢色差和宽度上染色印疵的形成原因.第2部分以实验经验,说明使用水不溶性染料产生的染色问题. 相似文献
57.
The paper presents an alternative constraint-handling technique that converts a nonlinear constrained programming problem
into an unconstrained multi-objective optimisation problem. The technique is derived from the behavioural memory constraint-handling
method, which was originally implemented for single-objective optimisation with genetic algorithms. We compare our presented
technique with two other popular constraint-handling concepts and demonstrate its superiority over them when applied to a
propeller optimisation problem. We conclude that the multi-objective behavioural memory constraint-handling technique conjugated
with the non-dominated sorting genetic algorithm (NSGA-II) is a prudent method to apply to problems with an infeasible initial
design and where constraints have a natural order of satisfaction, which, if not conformed to, would lead to unrealistic designs
that impair the search by GA. 相似文献
58.
59.
60.
Sergiy Antonyuk Stefan Heinrich Jürgen Tomas Niels G. Deen Maureen S. van Buijtenen J. A. M. Kuipers 《Granular Matter》2010,12(1):15-47
The discrete modelling and understanding of the particle dynamics in fluidized bed apparatuses, mixers, mills and others are
based on the knowledge about the physical properties of particles and their mechanical behaviour during slow, fast and repeated
stressing. In this paper model parameters (modulus of elasticity, stiffness, yield pressure, restitution coefficient and strength)
of spherical granules (γ-Al2O3, zeolites 4A and 13X, sodium benzoate) with different mechanical behaviour have been measured by single particle compression
and impact tests. Starting with the elastic compression behaviour of granules as described by Hertz theory, a new contact
model was developed to describe the force-displacement behaviour of elastic-plastic granules. The aim of this work is to understand
the energy absorption during compression (slow stressing velocity of 0.02 mm/s) and impact (the impact velocity of 0.5–4.5 m/s)
of granules. For all examined granules the estimated energy absorption during the impact is found to be far lower than that
during compression. Moreover, the measured restitution coefficient is independent of the impact velocity in the examined range
and independent of the load intensity by compression (i.e. maximum compressive load). In the case of repeated loading with
a constant load amplitude, the granules show cyclic hardening with increasing restitution coefficient up to a certain saturation
in the plastic deformation. A model was proposed to describe the increase of the contact stiffness with the number of cycles.
When the load amplitude is subsequently increased, further plastic deformation takes place and the restitution coefficient
strongly decreases. 相似文献