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Orngu Africa Orngu Ifeoma Elizabeth Mbaeyi-Nwaoha 《International Journal of Food Science & Technology》2022,57(6):3750-3759
Composite flours were prepared from blends of yellow maize (Zea mays), sesame seed (Sesamum indicum) and oyster mushroom (Pleurotus ostreatus) powder in the ratio of 80:20:0; 75:20:5; 70:20:10; 65:20:15 and 60:20:20, respectively to produce the cereal-based breakfast product coded as YSB, SMB, TMB, PMB and OMB with YSB as the control. The breakfast cereals were produced by hydration and toasting of yellow maize and sesame to 160°C for 25 min and blended together with oven-dried and packaged oyster mushroom. The developed products were analysed for proximate, vitamins, minerals and sensory properties. The proximate composition (%) of different blends ranged as moisture (4.07–7.08), ash (3.09–2.28), crude fat (16.04–12.83), crude fibre (4.30–8.22), protein (16.14–22.54), carbohydrate (56.34–47.04) and energy (434.34–393.83 Kcal). Vitamin A (7.99–5.98 mg/100 g), vitamin B1 (0.08–0.42 mg/100 g), vitamin B2 (0.06–0.15 mg/100 g), vitamin B3 (1.91–4.52 mg/100 g) and vitamin C (3.55–3.32 mg/100 g) were u while minerals (mg/100 g) were calcium (75.31–58.02), potassium (0.65–4.01), magnesium (12.25–12.62), iron (1.21–4.15) and zinc (0.40–1.32). Sensory scores revealed that the cereal-based breakfast product were acceptable to the panellist with oyster mushroom supplementation up to 10%. 相似文献
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Temperatures in excess of 60 °C are required for efficient bioleaching of chalcopyrite. Within heaps, colonisation of the mineral with thermophilic archaea is important in reaching and maintaining these high temperatures. The effect of temperature and culture history on the attachment of Metallosphaera hakonensis, an extreme thermophilic acidophile identified as a key player in heap bioleaching, to sulfide concentrates and low-grade ore was investigated in shake flasks and packed beds. Attachment studies were conducted at 25 °C, 45 °C and 65 °C. The results show a clear relationship between increasing temperature and attachment efficiency for both suspended and packed bed systems. Attachment at 25 °C was low. Increasing the temperature to 45 °C improved attachment efficiency by between 50% and 100% while a further increase to 65 °C improved attachment by an additional 20-50%. Cells cultured on elemental sulfur as energy source prior to contacting showed 1.3 times greater affinity for the mineral concentrate than those cultured on sulphide mineral concentrates or ferrous sulphate. In contrast to previous studies using mesophilic organisms the selective attachment of Metallosphaera to sulfide minerals, relative to gangue, was less pronounced. Attachment efficiency was lower in the packed bed system which more closely mimicked flow through a heap. The cell surface properties surface charge and hydrophobicity as well as metabolic activity were investigated to provide insight into the observed phenomena. The data suggest that retention of thermophiles within the heap could be enhanced by a secondary inoculation following elevation of the temperature above 40 °C by the mesophilic pioneer species. 相似文献
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饱水石灰岩骨架和流体弹性参数的估算 总被引:1,自引:0,他引:1
本文利用Niu等提出的基于临界孔隙度模型的组分弹性参数数值计算方法,把测试岩石样品的孔隙度、整体密度、纵波速度和横波速度作为数值计算的输入数据,运用"双线性数值计算方法"反演求出临界点、流体和骨架的12个弹性参数。具体做法是:基于临界孔隙度模型,给出三组线性关系,即密度—孔隙度,整体剪切模量—孔隙度,整体纵波模量—孔隙度,上述每组线性关系分别以孔隙度作为自变量和因变量得到两个线性方程,再把两个方程计算的结果进行加权平均得到相关的弹性参数估算值,并结合饱水石灰岩样品数据实现了弹性参数估算。数值计算结果表明,由数值计算得到的弹性参数与测试弹性参数的均值和方差相差甚微,特别是密度数据的偏差均值更小,说明文中的数值计算结果是可靠的。 相似文献
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N-Acylphosphatidylserines have been isolated from intact and injured tissues, but the participation of such acidic phospholipids
in membrane aggregation and fusion has not been demonstrated. We have synthesized N-stearoylphosphatidylserine (NSPS) and examined divalent-cation-induced aggregation of NSPS-liposomes, which leads to membrane
destabilization and fusion. The purified lipid was characterized by its chromatographic and spectroscopic (infrared and 1H nuclear magnetic resonance) properties and by its chemical degradation pattern. Aggregation of unilamellar NSPS-liposomes
was studied as a function of calcium and magnesium concentration. The ability of calcium and magnesium to induce vesicle aggregation
is higher for phosphatidylserine (PS)-liposomes (threshold concentration 1.5 mM for calcium and 4.6 mM for magnesium) than
for NSPS-liposomes (threshold concentration 2.8 mM for calcium and 6.6 mM for magnesium). The irreversibility of the aggregation
reactions after adding EDTA suggests that vesicle fusion might occur in the presence of calcium and magnesium. Preliminary
studies, based on mixing of both lipid and internal aqueous contents, show that fusion rather than aggregation of NSPS-liposomes
occurs in the presence of calcium ions. The tendency of NSPS-liposomes to aggregate at higher cation concentrations than PS-liposomes
suggests that N-acylation of phosphatidylserine protects the membrane against degenerative damage caused by aggregation and fusion. 相似文献
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Díaz B Sánchez-Espinel C Arruebo M Faro J de Miguel E Magadán S Yagüe C Fernández-Pacheco R Ibarra MR Santamaría J González-Fernández A 《Small (Weinheim an der Bergstrasse, Germany)》2008,4(11):2025-2034
Inorganic nanoparticles (NPs) show great potential for medicinal therapy. However, biocompatibility studies are essential to determine if they are safe. Here, five different NPs are compared for their cytotoxicity, internalization, aggregation in medium, and reactive oxygen species (ROS) production, using tumoral and normal human blood cells. Differences depending on the cell type are analyzed, and no direct correlation between ROS production and cell toxicity is found. Results are discussed with the aim of standardizing the procedures for the evaluation of the toxicity. 相似文献
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Cristina Fernandez‐Barranco Africa Yebra‐Rodriguez M. Dolores La Rubia‐Garcia Francisco J. Navas‐Martos Pedro Alvarez‐Lloret 《Polymer Composites》2015,36(12):2326-2333
Polyamide66 (PA66) and polyamide66/sepiolite (PA66/sepiolite) nanocomposites at 1, 3, 5, 7, and 9 wt% clay loading were prepared and injected to simulate industrial processing. Tensile tests were performed in the samples, and scanning electron microscopy was used to characterize the fracture surface. The samples were also examined by X‐ray Diffraction (XRD), Differential Scanning Calorimetry (DSC), and vibrational spectroscopy analysis (FT‐IR and FT‐Raman). Higher tensile strength and stiffness and reduction of the strain to failure are observed in the nanocomposites with higher sepiolite content. Two‐dimensional XRD analyses show that the sepiolite also enhances the orientation of PA66 crystals. XRD and spectroscopic analyses corroborate that the nanoclay fibers are placed between the lamellar superstructure of the PA66 without affecting the polymer chains. DSC confirms that the presence of sepiolite does not influence the crystallinity nor the nucleation of PA66 as the arrangement of the fibers between the PA66 lamellae hinders the nucleation of new crystals. We propose a model for the crystallographic organization of the organic and inorganic phases in the PA66/sepiolite nanocomposites. POLYM. COMPOS., 36:2326–2333, 2015. © 2014 Society of Plastics Engineers 相似文献
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Antonio Madroñero De La Cal Juan Aguado-Serrano Maria Luisa Rojas-Cervantes Elena V. Rosa Adame Belen Sarmiento Marron Africa Castro Rosende Roman Nevshupa 《Microscopy research and technique》2009,72(6):447-453
The hydrogen absorption process is studied in carbonaceous fibers produced from a mixture of methane and hydrogen. The absorption of the hydrogen was examined in two types of fibers, in “as-grown” state and after a process of desorption during an annealing to 1.473 K under vacuum. Later to its production process, the fibers withstand an oxidation in air to 973 K. The fibers were examined by means of scanning electron microscopy (SEM) and confocal microscopy by reflection. Differences in the behavior during the oxidation were observed between the fibers in as-grown state and those subjected to a further annealing. It could be verified that the fibers were really constituted by two different phases. In one of the phases, the storage of the hydrogen absorbed took place, whereas in the other phase there was no alteration. The process of annealing prior to the absorption of the hydrogen has an appreciable effect on the desorption rate of the hydrogen. Microsc. Res. Tech., 2009. © 2009 Wiley-Liss, Inc. 相似文献