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411.
Several key compounds for the final beer flavour (higher alcohols, esters, vicinal diketones) are produced during the alcoholic fermentation phase. The paper demonstrates the possibility of obtaining various desired final aroma profiles and reducing the total process time using dynamic optimisation of three control variables: temperature, top pressure and initial yeast concentration in the fermentation tank. The optimisation is based on a sequential quadratic programming algorithm, on a dynamic model of the alcoholic fermentation and on an aroma production model. The robustness of the optimal control profile with respect to model uncertainty is discussed. 相似文献
412.
Summary Experimental and theoretical data proving the existence of long-lived (living) poly(methyl methacrylate-co-styrene) 5050 random macroradicals are presented. 相似文献
413.
The nonlinear motion equation of a spherical particle pushed by the solidification front is determined. In equilibrium, by
integrating this equation, we obtain the critical interfacial speed, both in the absence and presence of thermal conductivities.
The results are similar to those given by Ştef<anescuet al. only in the case of ionic crystals (n = 2). The analysis of the motion of the particle far from the interface makes it possible to introduce a time constant as
a measure of the motion uniformity degree. In such a context, it may be assumed that the lesser the time constant, the quicker
the incorporation of the particle by the metal matrix. 相似文献
414.
Irina Jemna E. Luca P. Nicolau C. Tnsoiu C. Ioan 《Journal of the American Ceramic Society》1983,66(9):c166-c167
Two piezoelectric materials were investigated in electric fields, up to 3 kV/cm to determine whether single-sample testing can be used to evaluate piezoelectric coupling. Autocorrelation analysis of the data showed that the minimal increment of electric field necessary for successive independent measurements on single specimens is 1.3 kV /cm. This value coincides with the breakage field of the sample at resonance. Electrumechanical performance can still be evaluated with a sampling interval slightly lower than 1.3 kV/cm . 相似文献
415.
Anca-Dana Bendrea Luminita Cianga Gabriela-Liliana Ailiesei Demet Gen Colak Irina Popescu Ioan Cianga 《International journal of molecular sciences》2022,23(14)
Because the combination of π-conjugated polymers with biocompatible synthetic counterparts leads to the development of bio-relevant functional materials, this paper reports a new oligo(2-methyl-2-oxazoline) (OMeOx)-containing thiophene macromonomer, denoted Th-OMeOx. It can be used as a reactive precursor for synthesis of a polymerizable 2,2’-3-OMeOx-substituted bithiophene by Suzuki coupling. Also a grafted polythiophene amphiphile with OMeOx side chains was synthesized by its self-acid-assisted polymerization (SAAP) in bulk. The results showed that Th-OMeOx is not only a reactive intermediate but also a versatile functional material in itself. This is due to the presence of 2-bromo-substituted thiophene and ω-hydroxyl functional end-groups, and due to the multiple functionalities encoded in its structure (photosensitivity, water self-dispersibility, self-assembling capacity). Thus, analysis of its behavior in solvents of different selectivities revealed that Th-OMeOx forms self-assembled structures (micelles or vesicles) by “direct dissolution”.Unexpectedly, by exciting the Th-OMeOx micelles formed in water with λabs of the OMeOx repeating units, the intensity of fluorescence emission varied in a concentration-dependent manner.These self-assembled structures showed excitation-dependent luminescence as well. Attributed to the clusteroluminescence phenomenon due to the aggregation and through space interactions of electron-rich groups in non-conjugated, non-aromatic OMeOx, this behavior certifies that polypeptides mimic the character of Th-OMeOx as a non-conventional intrinsic luminescent material. 相似文献
416.
With the new regulations and policies related to climate change, the construction industry has been put under pressure to increase the sustainability of its practices. Many organisations are now adapting their practices to meet government legislative targets (e.g. reducing carbon emissions) and consider the environmental, social and economic performance of buildings. In addition, the sustainable construction is also a rapidly changing field, with technological advances, changes in legislation and increasingly educated clients driving the industry to constantly adapt to remain competitive. This represents a key problem for construction professionals as they must continually be aware of new information, best practices, technologies and changing legislation (at a local, national and international level) which are often disseminated from different organisations/individuals through dispersed media. 相似文献
417.
Ioana Cucu Mihnea Ioan Nicolescu tefan-Sebastian Busnatu Ctlin Gabriel Manole 《International journal of molecular sciences》2022,23(10)
Cardiac interstitium is a complex and dynamic environment, vital for normal cardiac structure and function. Telocytes are active cellular players in regulating main events that feature myocardial homeostasis and orchestrating its involvement in heart pathology. Despite the great amount of data suggesting (microscopically, proteomically, genetically, etc.) the implications of telocytes in the different physiological and reparatory/regenerative processes of the heart, understanding their involvement in realizing the heart’s mature cytoarchitecture is still at its dawn. Our scrutiny of the recent literature gave clearer insights into the implications of telocytes in the WNT signaling pathway, but also TGFB and PI3K/AKT pathways that, inter alia, conduct cardiomyocytes differentiation, maturation and final integration into heart adult architecture. These data also strengthen evidence for telocytes as promising candidates for cellular therapies in various heart pathologies. 相似文献
418.
Ioan Tomescu 《Theoretical computer science》2003,290(3):2031-2035
We previously proved that almost all words of length n over a finite alphabet A with m letters contain as factors all words of length k(n) over A as n→∞, provided limsupn→∞ k(n)/log n<1/log m.
In this note it is shown that if this condition holds, then the number of occurrences of any word of length k(n) as a factor into almost all words of length n is at least s(n), where limn→∞ log s(n)/log n=0. In particular, this number of occurrences is bounded below by C log n as n→∞, for any absolute constant C>0. 相似文献
419.
420.
Roxana-Diana Pasca Aurora Mocanu Simona-Codruta Cobzac Ioan Petean Ossi Horovitz 《Particulate Science and Technology》2014,32(2):131-137
A biogenic approach for the synthesis of gold nanoparticles (GNPs) by reducing chloroauric acid (HAuCl4) with three different plant extracts (from Angelica, Hypericum, and Hamamelis) is described. The content of reducing compounds (polyphenols) in each plant extract was determined by photometric dosing. The formation of GNPs was tracked by ultraviolet-visible spectroscopy and their characterization was performed using transmission electron microscopy (TEM) and atomic force microscopy (AFM) imaging and FTIR spectra. GNPs, with diameters ranging from about 4 nm to 8 nm, were obtained at room temperature and pH value about 8. They present various shapes from spherical, to ovals, heart or polyhedral forms. Generally, the GNPs colloidal dispersions are rather stable in time, and the self assembly of GNPs is sparsely observed. However, at lower concentration of the plant extract the tendency to self aggregation of the GNPs increased. The plant extracts contain reducing agents, compounds with stabilizing effect on the GNPs, but also components which mediate their self assembly. The GNPs obtained by these biogenic syntheses have potential biological and medical applications, taking into account at least two characteristics, their size and aqueous stability. 相似文献