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861.
862.
Anna Korus Zofia Lisiewska Jacek Słupski Piotr Gębczyński 《International Journal of Food Science & Technology》2012,47(9):1882-1888
The present work determined iron content in fourteen species of vegetable prepared for consumption. The experimental material consisted of raw and boiled raw vegetables and two types of frozen product: one traditionally produced (blanching before freezing); the other obtained using the modified method (boiling before freezing), having the characteristics of a ready‐to‐eat convenience product. Nutrient density (ND) and recommended dietary intake (RDI) were established on the basis of iron content. The highest iron content was found in pea seeds (2.03 mg per 100 g fresh weight) and the lowest in root vegetables (0.38–0.60 mg). Iron retention was similar in all pea, broad bean, New Zealand spinach, kale, white cauliflower, celery and red beet products. In the remaining products, the significantly lowest retention was found in the traditionally frozen product (Sample C) and the highest in the ‘convenience’ frozen product (Sample D). The above‐mentioned order also applied to ND and RDI values. Only in the ND of parsnip calculated for women did any value fall below 100%. 相似文献
863.
Nanostructured vanadium nitride and carbide catalysts were prepared by the nitridation and carburization of vanadium oxide
supported on M41S materials (MCM-41 and SBA-15) and activated carbon. The oxide precursors, V2O5/M41S, were obtained in three different synthesis strategies using “in situ” and “ex situ” incorporation of vanadia precursors
(V(acac)3) into the mesoporous host. For the oxide precursors specific surface areas exceeding 1,200 m2 g−1 were achieved. After nitridation a slight decrease of surface area was observed. All VN catalysts show a high activity in
propane dehydrogenation with a selectivity exceeding 80% towards propene. Impregnation and nitridation conditions have profound
influence upon the catalytic activity. The highest activity was observed for VN supported on NORIT A. 相似文献
864.
Wacaw Makowski Lucjan Chmielarz Piotr Kutrowski 《Microporous and mesoporous materials》2009,120(3):257-262
Temperature programmed desorption profiles of n-nonane were measured for MCM-41, SBA-15 and HMS mesoporous silicas under quasi-equilibrium conditions using standard TPD setup with a chromatographic detector, utilizing He + 0.4% n-C9H20 mixture as a carrier gas. A method for determination of the pore size distributions according to a modified BJH scheme, based on the Kelvin equation for the fluid core radius and the BET-type function for the adsorbed film thickness, was proposed. The resulting pore size distributions are in good agreement with those obtained by standard BJH analysis of the N2 desorption isotherms. 相似文献
865.
Jeferson L. Klug René Hagemann Nestor C. Heck Antônio C. F. Vilela Hans P. Heller Piotr R. Scheller 《国际钢铁研究》2012,83(12):1186-1193
The main problem related to the development of fluorine‐free mould powders for slab casting is effectively controlling the heat transfer between the steel shell and mould. In commercial mould powders crystallization of cuspidine (Ca4Si2O7F2) from mould slag has a great effect on heat‐transfer control. In industrial process the crystallization rate for a fluorine‐free mould slag should be similar to the crystallization rate of cuspidine. To evaluate the crystallization rate for slags time‐temperature‐transformation (TTT) diagrams can be constructed using the Single Hot Thermocouple Technique by in situ observation. In the present work, fundamental information related to crystallization control in the CaO–SiO2–TiO2–Na2O–Al2O3 system was obtained. It was observed that the addition of Na2O in CaO–SiO2–TiO2 slags dramatically shortens the crystals' incubation times in TTT diagrams to the range of seconds. It is possible to control the crystallization kinetics in CaO–SiO2–TiO2 slags by changing the Na2O content. Some observations for the crystals' morphology are reported. 相似文献
866.
Agata Motyka-Pomagruk Anna Dzimitrowicz Jakub Orlowski Weronika Babinska Dominik Terefinko Michal Rychlowski Michal Prusinski Pawel Pohl Ewa Lojkowska Piotr Jamroz Wojciech Sledz 《International journal of molecular sciences》2021,22(17)
Plant pathogenic bacteria cause significant economic losses in the global food production sector. To secure an adequate amount of high-quality nutrition for the growing human population, novel approaches need to be undertaken to combat plant disease-causing agents. As the currently available methods to eliminate bacterial phytopathogens are scarce, we evaluated the effectiveness and mechanism of action of a non-thermal atmospheric pressure plasma (NTAPP). It was ignited from a dielectric barrier discharge (DBD) operation in a plasma pencil, and applied for the first time for eradication of Dickeya and Pectobacterium spp., inoculated either on glass spheres or mung bean seeds. Furthermore, the impact of the DBD exposure on mung bean seeds germination and seedlings growth was estimated. The observed bacterial inactivation rates exceeded 3.07 logs. The two-minute DBD exposure stimulated by 3–4% the germination rate of mung bean seeds and by 13.4% subsequent early growth of the seedlings. On the contrary, a detrimental action of the four-minute DBD subjection on seed germination and early growth of the sprouts was noted shortly after the treatment. However, this effect was no longer observed or reduced to 9.7% after the 96 h incubation period. Due to the application of optical emission spectrometry (OES), transmission electron microscopy (TEM), and confocal laser scanning microscopy (CLSM), we found that the generated reactive oxygen and nitrogen species (RONS), i.e., N2, N2+, NO, OH, NH, and O, probably led to the denaturation and aggregation of DNA, proteins, and ribosomes. Furthermore, the cellular membrane disrupted, leading to an outflow of the cytoplasm from the DBD-exposed cells. This study suggests the potential applicability of NTAPPs as eco-friendly and innovative plant protection methods. 相似文献
867.
A new setup of interferometers is proposed in which the set of specific optical markers--optical vortices--could be generated. The classical Mach-Zender two-beam interferometer has been modernized using the Wollaston prism. In this setup, the optical vortices could be obtained for a wide range of both beam parameters. The numerical analysis and experiments confirm our theoretical predictions. 相似文献
868.
Suffczynski P Lopes da Silva FH Parra J Velis DN Bouwman BM van Rijn CM van Hese P Boon P Khosravani H Derchansky M Carlen P Kalitzin S 《IEEE transactions on bio-medical engineering》2006,53(3):524-532
In this paper, we investigate the dynamical scenarios of transitions between normal and paroxysmal state in epilepsy. We assume that some epileptic neural network are bistable i.e., they feature two operational states, ictal and interictal that co-exist. The transitions between these two states may occur according to a Poisson process, a random walk process or as a result of deterministic time-dependent mechanisms. We analyze data from animal models of absence epilepsy, human epilepsies and in vitro models. The distributions of durations of ictal and interictal epochs are fitted with a gamma distribution. On the basis of qualitative features of the fits, we identify the dynamical processes that may have generated the underlying data. The analysis showed that the following hold. 1) The dynamics of ictal epochs differ from those of interictal states. 2) Seizure initiation can be accounted for by a random walk process while seizure termination is often mediated by deterministic mechanisms. 3) In certain cases, the transitions between ictal and interictal states can be modeled by a Poisson process operating in a bistable network. These results imply that exact prediction of seizure occurrence is not possible but termination of an ictal state by appropriate counter stimulation might be feasible. 相似文献
869.
Sekula J Everaert J Bohets H Vissers B Pietraszkiewicz M Pietraszkiewicz O Du Prez F Vanhoutte K Prus P Nagels LJ 《Analytical chemistry》2006,78(11):3772-3779
Capillary electrophoresis was coupled successfully and reliably to potentiometric sensors, which are based on an ionically conductive rubber phase coating, applied on a 250 microm diameter metal substrate. The membrane components included potassium tetrakis(p-chlorophenyl)borate (TCPB), bis(2-ethylhexyl)sebacate (DOS), and high molecular mass poly(vinyl chloride) (PVC). Potentiometry reveals a very sensitive CE detection mode, with sub-micromolar detection limits for amines and the randomly chosen drugs quinine, clozapine, cocaine, heroine, noscapine, papaverine, and ritodrine. The lowest detection limit, 1 x 10(-8) M injected concentration, was obtained for the quaternary ammonium compound tetrahexylammonium chloride. The more polar lower aliphatic amines and the biogenic amines dopamine, adrenaline, and cadaverine have much higher detection limits. The detection limits are log P dependent. Addition of a commercially available calixarene molecule or a synthetic macrocyclic amphiphilic receptor molecule to the electrode coatings enhanced the sensitivity respectively for the lower aliphatic amines and for the biogenic amines. A transpose of the Nikolskii-Eisenman-type function was suggested and used to convert the signal of the detector to a concentration-dependent signal. 相似文献
870.
Rafał Piotr Jastrzębski Riku Pöllänen 《Electrical Engineering (Archiv fur Elektrotechnik)》2009,91(2):101-114
This paper discusses a closed-loop centralized control for a multi-input multi-output active magnetic bearing system. A genetic
algorithm for design and a credible comparison of different controller structures are proposed. The evaluation of the design
trade-offs of linear-quadratic and loop transfer recovery controllers are studied. The model-based controllers are compared
with the classical PID controller and the cascaded PI/PD controller. The properties of the tested control configurations are
examined using maximum singular values of the output sensitivity function of the closed-loop system and the tolerated disturbance
at the input of the plant. Furthermore, indices such as measured peak output sensitivity, singular values of the uncertain
control system, responses to the step reference position, step disturbance, and impulse force disturbance are examined. A
good agreement between the simulation and the experimental results from the test-rig is shown. 相似文献