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11.
This study determined the physicochemical, sensorial and nutritional properties of breadsticks to which a resistant starch (RS)-rich ingredient was incorporated by partial substitution, that is, 40%–70%, of hard wheat flour in the control recipe. Wheat flour substitution at the levels exceeding 50% lightened the colour while decreasing the moisture content and hardness of breadsticks, which was explainable by the microstructure. Changes in properties of breadsticks also affected the suitability of its sensory attributes, particularly colour and texture. Breadsticks, of which half of wheat flour was substituted, contained less protein and calories but higher carbohydrate than the control formula. Such flour substitution increased RS content closed to its effective dose of 15 g in a 45-g serving, which led to approximately 15% reduction in in vitro glycaemic index. Therefore, incorporating effective dose of RS in breadsticks could be performed, without causing substantial changes in product quality, by partial substitution of wheat flour.  相似文献   
12.
The various metal ratios of PdCoNi/G nanocomposites (PdCoNi/G 6:1:1, 6:3:3, 6:4.5:1.5, 6:1.5:4.5, and 6:9:9) supported on graphene were synthesized using a chemical reduction of metal compounds and graphite oxide with a strong reducing agent under N2 conditions without calcinations to improve the electrocatalytic performance for methanol electrooxidation. SEM, EDX, XRD, XPS, and XANES were used to study the physical and chemical properties of all electrocatalysts. The composition of PdCoNi/G electrocatalysts was in the form of palladium metal, cobalt oxides, and nickel oxide. The electrocatalysis activity of methanol oxidation in 1 M KOH was investigated by cyclic voltammetry and chronoamperometry. It was found that PdCoNi/G (6:1:1) nanocomposite enhanced the catalytic activity. The relative potential showed the highest current density (17.27 mA/cm2) and negative potential (??0.065 V) in the catalyst studies. In addition, PdCoNi/G (6:1:1) nanoncomposite presented the best intermediate poisoning tolerance for the methanol oxidation of all synthesized electrocatalysts. These confirmed that PdCoNi/G (6:1:1) is very promising for applications in direct methanol fuel cell (DMFC).

Graphical Abstract

Schematic illustration of the synthesis of PdCoNi metal nanocomposites (various metal ratios) supported on graphene (a) oxidation of graphite to GO and (b) reduction between GO and metal compounds with NaBH4 as a reducing agent.
  相似文献   
13.
A catholyte is a key factor to hydrogen production in microbial electrolysis cells (MECs). Among the four groups of catholytes investigated in this study, a 100 mM phosphate buffer solution (PBS) resulted in the highest hydrogen production rate of 0.237 ± 0.031 m3H2/m3/d, followed by 0.171 ± 0.012 m3H2/m3/d with a 134 mM NaCl solution and 0.171 ± 0.004 m3H2/m3/d with the acidified water adjusted with sulfuric acid. The MEC with all catholytes achieved good organic removal efficiency, but the removal rate varied following the trend of the hydrogen production rate. The reuse of the catholyte for an extended period led to a decreasing hydrogen production rate, affected by the elevated pH. The cost of both the acidified water and the NaCl solution was much lower than the PBS, and therefore, they could be a better choice as an MEC catholyte with further consideration of cost reduction and chemical reuse/disposal.  相似文献   
14.
Physical properties and the microstructure of Som-fug, a Thai-style fermented fish sausage, with seven different commercial brands were determined. The released water contents of Som-fug samples ranged from 5.81 to 15.81% and expressible water contents were different among the samples tested (p<0.05). Differences in hardness, fracturability, adhesiveness, springiness, cohesiveness and resilience were also observed. L*, a*, b* and whiteness varied with the samples. Overall, the samples had different acceptability in texture and color. Microstructural study revealed that Som-fug had a three-dimensional network. A more void and open structure correlated well with greater released water and was associated with lower hardness and cohesiveness. Therefore, the different physical properties and microstructure of Som-fug could be influenced by the differences in raw materials, ingredients, processing, and fermentation characteristics, and determined the acceptability of products.  相似文献   
15.
Curcumin, a major active compound in the turmeric rhizome, has many biological properties, especially anti-leukemia activity. The overexpression of FMS-like tyrosine kinase 3 protein with internal tandem duplication (FLT3-ITD) mutation protein was related to the poor prognosis and disease progression of leukemia. In this study, the cytotoxicity and inhibitory effect of curcumin on cell cycle of FLT3-ITD overexpressing MV4-11 leukemic cells were evaluated. Moreover, curcumin polymeric micelles conjugated with FLT3-specific peptide (FLT3-Cur-micelles) were prepared using a film hydration method to increase curcumin solubility and the inhibitory effect on MV4-11 cells was evaluated. Cytotoxicity and cell cycle analysis were performed using an MTT assay and flow cytometry, respectively. Physical properties of FLT3-Cur-micelles, including particle size, size distribution, morphology, and entrapment efficiency (EE), were evaluated. Cellular uptake of the micelles on MV4-11 cells was determined by flow cytometry and fluorescence microscopy. FLT3-Cur-micelles were observed with size less than 50?nm and high EE of >75%. In addition, FLT3-Cur-micelles demonstrated excellent internalization and increased curcumin accumulation in leukemic cells when compared to free curcumin. Furthermore, FLT3-Cur-micelles exhibited a strong cytotoxic effect on MV4-11 cells with IC50 value of 1.1?µM, whereas the blank micelles showed no effect. Furthermore, FLT3-Cur-micelles showed no significant effect on normal human PBMCs with IC50 value >25?µM. In summary, FLT3-Cur-micelles are a promising nanocarrier system for enhancing anti-leukemic activity of curcumin and suitable for further preclinical studies.  相似文献   
16.
The Children Act focuses attention on meeting the assessed needs of children with disabilities. General practitioners (GPs) and Community Child Health (CCH) doctors in one health district were asked by postal questionnaire who it was who currently assessed such needs and who would do so in the future. The involvement of GPs (15) varied from none (1) to regular reassessment (3). Nearly all (14) treated acute illnesses but educational assessments were assigned to CCH doctors. Community doctors (9) had a clearer idea of their role including regular reassessment (9), education assessment (9) and interagency liaison (3). Both groups complained of poor communication with each other and with hospital services. To fulfil the requirements of the Children Act, community child health services, family health services authorities and district health authorities will have to specify how and by whom children with disabilities are identified and assessed. Arrangements will vary according to local service development. These arrangements, and the resulting liaison with other agencies, should be specified in National Health Service contracts, thus improving communication and cooperation.  相似文献   
17.
OBJECTIVES: The aim of this investigation was to evaluate the significance of selected surface texture parameters used to describe and quantify the effect of tooth brushing with various "tooth whitening" dentifrices on a resin composite surface in vitro. METHODS: Specimens of a microfil resin composite were brushed with selected dentifrices. Surface texture profiles were acquired and analyzed both pre- and post-brushing using a contact diamond stylus. The selected parameters chosen to describe the surface texture were Ra, Rz, Rpm and the Rpm:Rz ratio. Differences between toothpastes were assessed using an ANOVA and a multiple comparisons test, the Student Newman-Keuls procedure. P and t values were calculated to determine if any of the surface roughness parameters were significantly changed by brushing. RESULTS: The results indicate that there were significant changes in the surface texture of the resin composite following tooth brushing with the selected dentifrices. For example, the use of Clinomyn significantly increased the surface roughness of the resin composite, as measured by the Rz parameter, from 2.19 +/- 1.67 microns to 10.02 +/- 2.57 microns (p < 0.05). In addition, the surface texture parameters chosen to describe the properties of the surface should reflect a knowledge of profile shape such as Rpm:Rz ratio, and care should be taken if measurements of surface texture of dental restorative materials are to be used as predictors of clinical performance. SIGNIFICANCE: All the toothpastes chosen for this investigation left a surface on the resin composite which may be prone to crack propagation during "vertical barrelling" movements generated during mastication. However, this may be more of a function of the rigidity of the restorative material rather than the surface left after tooth brushing.  相似文献   
18.
Different Pt/KL catalysts containing rare earth (RE; Ce and Yb) promoters were prepared by two techniques, incipient wetness impregnation (IWI) and vapor phase impregnation (VPI). The catalysts were tested for the activity and the selectivity of n-hexane aromatization to benzene under clean, sulfur-containing, and water-containing feeds at 500 °C. It was observed that the catalysts prepared by the VPI technique exhibited much higher activity and selectivity than those prepared by IWI. It was also found that although under clean conditions, the addition of Ce or Yb caused a decrease in activity, in the presence of sulfur the addition of Ce and to a lesser extent Yb, significantly inhibited catalyst deactivation.

The influence of water in the feed was investigated by contacting the catalysts for 1 h to a feed containing 3 mol.% water. After this treatment, all the catalysts exhibited a significant activity loss. This loss was more pronounced for the catalyst prepared by the VPI method. The catalyst prepared by IWI already had suffered a significant deactivation before the water treatment, so the activity drop was not so pronounced. The sample prepared by VPI not only showed a drop in activity immediately after the water treatment but it became more susceptible to deactivation afterwards. By contrast, the Ce-promoted catalyst showed a more stable activity after the water treatment.

All catalysts were characterized before and after reaction by a number of techniques. In agreement with previous studies, FT-IR of adsorbed CO and chemisorption results indicated that the VPI method resulted in higher Pt dispersion than that obtained by the IWI method. After reaction in the presence of sulfur, the Ce-promoted Pt/KL catalyst showed a higher resistance to metal agglomeration and a lower rate of coke formation than the unpromoted Pt/KL. On all the catalysts, the amount of carbon deposits was greater in the presence of sulfur and after exposure to water vapor than under the reaction with clean feeds. This difference is explained in terms of metal particle growth and location in the zeolite.  相似文献   

19.
Short-oil alkyd resins were prepared by using five different oil types: corn oil, rice bran oil, sunflower oil, soya bean oil and dehydrated castor oil (DCO). Among these, soya bean oil gave alkyd resin with the darkest color because oxidation occurred. Auto air-dried coating films were developed and it was shown that film prepared from rice bran oil-based alkyd exhibited the longest drying time due to the low number of double bonds compared to other and the extra natural antioxidant in rice bran oil. DCO alkyd-based film revealed the shortest drying time, the greatest hardness but the poorest alkali and sea-water resistance. This is caused by the differences in the type of fatty acid and double bonds, the high amount of double bonds being in DCO. In addition, an increase in the reaction temperature only had an influence on darkening the alkyd color and decreasing the drying time of coating films. In terms of technical properties and cost competitiveness, soya bean oil-based film is the best. Coating films derived from all oil-based alkyds, except DCO, look promising for use in surfboard manufacturing.  相似文献   
20.
Platinum catalysts supported on the potassium-form of different large-pore zeolites (i.e. K-LTL, K-BEA, K-MAZ, and K-FAU) have been tested for n-octane aromatization at 500 °C. All catalysts were prepared by the vapor phase impregnation (VPI) method. It was found that the Pt/K-LTL catalyst exhibit a better aromatization performance than the other zeolite catalysts. However, due to secondary hydrogenolysis, the C8 aromatics produced inside the zeolite are converted to benzene and toluene. By contrast, a non-microporous Pt/SiO2 catalyst did not present the secondary hydrogenolysis. Therefore, despite a lower initial aromatization activity, Pt/SiO2 results in higher selectivity to C8 aromatics than any of the other zeolite catalysts. All fresh catalysts were characterized by hydrogen chemisorption and FT-IR of adsorbed CO. In addition, the residual acidity of the supports was analyzed by temperature programmed desorption (TPD) of ammonia. In agreement with previous studies, it was found that after reduction at either 350 or 500 °C, the Pt/K-LTL showed much higher Pt dispersion than other catalysts. It is known that the structure of L zeolite can stabilize the small Pt clusters inside the zeolite channel. By contrast, FT-IR indicated that a large fraction of platinum clusters were located outside the zeolite channels in the case of Pt/K-BEA and Pt/K-MAZ catalysts.  相似文献   
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