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91.
A feeding experiment with brown layers was carried out to find effects of graded levels of rapeseed (without, 15% and 30%) in layer diets on the fatty acid composition of egg yolk and related functional properties of such modified eggs. A considerable increase of the content of essential n-3 fatty acids in egg yolk fat was noticed by including graded levels of rapeseed in layer diets. The destruction force of a gel prepared from whole egg was improved by the highest rapeseed level (30%) and emulsifying capacity by medium inclusion of rapeseed in layer diets (15%). The thermal stability of an emulsion prepared from whole egg was not influenced by rape feeding. Viscosity of mayonnaise prepared from egg yolk and whole egg yolk was decreased by increased rapeseed levels in the diets. In tendency, organoleptic evaluation of sponge cake prepared from whole egg revealed better results for the control group. The baking height of sponge cake was improved by rapeseed inclusion in layer diets. It may be assumed that all these changes caused by rapeseed feeding are closely related to the mentioned changes in the fatty acid profile.  相似文献   
92.
The yeast Saccharomyces cerevisiae transforms branched‐chain and aromatic amino acids into higher alcohols in the Ehrlich pathway. During microbiological culturing and industrial fermentations, this yeast is confronted with amino acids modified by reducing sugars in the Maillard reaction (glycation). In order to gain some preliminary insight into the physiological “handling” of glycated amino acids by yeasts, individual Maillard reaction products (MRPs: fructosyllysine, carboxymethyllysine, pyrraline, formyline, maltosine, methylglyoxal‐derived hydroimidazolone) were administered to two strains of S. cerevisiae in a rich medium. Only formyline was converted into the corresponding α‐hydroxy acid, to a small extent (10 %). Dipeptide‐bound pyrraline and maltosine were removed from the medium with concomitant emergence of several metabolites. Pyrraline was mainly converted into the corresponding Ehrlich alcohol (20–60 %) and maltosine into the corresponding α‐hydroxy acid (40–60 %). Five specific metabolites of glycated amino acids were synthesized and characterized. We show for the first time that S. cerevisiae can use glycated amino acids as a nitrogen source and transform them into new metabolites, provided that the substances can be transported across the cell membrane.  相似文献   
93.
The ever‐growing number of pathogenic bacteria resistant to treatment with antibiotics call for the development of novel compounds with as‐yet unexplored modes of action. Here, we demonstrate the in vivo antibacterial activity of carba‐α‐d ‐glucosamine (CGlcN). In this mode of action study, we provide evidence that CGlcN‐mediated growth inhibition is due to glmS ribozyme activation, and we demonstrate that CGlcN hijacks an endogenous activation pathway, hence utilizing a prodrug mechanism. This is the first report describing antibacterial activity mediated by activating the self‐cleaving properties of a ribozyme. Our results open the path towards a compound class with an entirely novel and distinct molecular mechanism.  相似文献   
94.
A convenient and simple strategy for preparing water soluble, photoluminescent functionalized silica nanoparticles (M-dots) in the absence of fluorophores or metal doping is demonstrated. These M-dots can be used for bioimaging using one and two-photon microscopy. Because of their high photostability, low toxicity and high biocompatibility compared with Lumidot? CdSe/ZnS quantum dots, functionalized silica particles are superior alternatives for current bioimaging platforms. Moreover, the presence of a free amine group at the surface of the M-dots allows biomolecule conjugation (e.g. with antibodies, proteins) in a single step for converting these photoluminescent SiO(2) nanoparticles into multifunctional efficient vehicles for theragnostics.  相似文献   
95.
Cells are highly organized objects containing millions of molecules. Each biomolecule has a specific shape in order to interact with others in the complex machinery. Spatial dynamics emerge in this system on length and time scales which can not yet be modeled with full atomic detail. This review gives an overview of methods which can be used to simulate the complete cell at least with molecular detail, especially Brownian dynamics simulations. Such simulations require correct implementation of the diffusion-controlled reaction scheme occurring on this level. Implementations and applications of spatial simulations are presented, and finally it is discussed how the atomic level can be included for instance in multi-scale simulation methods.  相似文献   
96.
Topics in Catalysis - The process of synthesis of formic acid via partial peroxide oxidation of methane over Fe-MFI zeolites, as well as the influence of the catalyst activation by oxalic acid on...  相似文献   
97.
Three developmental alumina-forming austenitic stainless steels were exposed to metal dusting conditions at 650?°C in a gas of 50%CO–49%H2–1%H2O (a C: 36.7 and $ p_{{{\text{O}}_{2} }} $ : 2.83?×?10?26?atm) under thermal cycling conditions. Metal wastage measurement showed initially slow kinetics followed by a fast weight loss. This observation is attributed to the formation of protective chromia/alumina oxide scales in the early stage of the reaction, followed by local oxide failure/spallation during cyclic reaction. Metal dusting initiated from these local defects, and pitting-type attack was observed after 131 cycles of reaction. After 352 cycles, severe dusting had developed, forming heavy and distinctive “tentacles” of superficial coke. This carbon deposit was composed of fine carbon filaments. Examination by TEM of the coke-metal reaction front showed direct surface metal disintegration, indicating that the dusting follows the classical mechanism for austenitic materials. Etching with aqua regia revealed a carburised zone formed in the alloy underneath the coke layer. Analysis by TEM of this zone revealed the formation of ultra-fine, needle-shaped chromium carbide precipitates within a chromium depleted austenite matrix.  相似文献   
98.
通过在传统的短路过渡电弧和射流过渡电弧的基础上进行创新,发展新型的焊接电弧,可以显著地提高电弧焊接在金属连接中的优越性。两种新的焊接电弧,forceArc~杂志焊接电弧和coldArc~焊接电弧可以在一个焊接电源上实现,对焊接生产具有现实意义。了解和掌握这些新型电弧的工艺特点,可以有效地将其应用到生产中,以此提高焊接产品的质量和焊接生产的经济效益。新型焊接电弧的出现使现有的有关焊前焊接接头准备的标准和规定,特别是有关坡口角度和焊接位置,需要重新考虑。新型焊接电弧可以应用于各种金属加工工业中的焊接生产,是对弧焊工艺的一个创新。  相似文献   
99.
In the present work, nanocatalysts prepared on inorganic supports (zeolites) were investigated in d-glucose oxidation and compared to systems supported on polymer (hypercrosslinked polystyrene (HPS)) previously described. Catalytic activities and selectivities were measured under various reaction conditions. The selectivity of d-glucose oxidation and activity of both Pd-containing zeolites and HPS-Ru were similar (99.7% and TOF 0.013–0.014 mol/(mol Me s)). Physicochemical analysis X-ray photoelectron spectroscopy, liquid nitrogen physisorption, diffuse reflectance infrared Fourier transform spectroscopy of adsorbed CO for metal sites evaluation, CD3CN for acid sites evaluation showed that Pd species were in oxidic form, while Ru species were in oxidic and reduced form. The catalytic activity decreased when acidic sites were present in Pd-containing zeolites.  相似文献   
100.
Production-integrated environmental protection – Utilization of residues . Chemical plants as well as coal-fired powerstations utilize chemical reactions in order to produce materials or energy. Most of these reactions additionally produce gaseous, liquid, or solid residues. It is the main objective of production-integrated environmental protection to use these residues as suitable feedstocks in order to reduce environmental pollution and lower the consumption of raw materials. Several examples from the BASF Group will show how, by crossing the borders of the respective plant, reasonable solutions for material, or at least energetic, utilization of residues can be achieved. As a result of permanent efforts in production-integrated environmental protection over many years and despite increasing outputs the emissions of the chemical industry have been continuously reduced.  相似文献   
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