The drive to utilise different lipids, both for health benefits and for commercial reasons, in bakery goods has been extensive. However, the roles of the lipid plays in many products, let alone the influence of the level of saturation, are uncertain. The objective of work carried out is to understand how the typical ingredients in biscuit would impact on the thermal profile of semi-sweet biscuit dough. Three different techniques have been used namely gravimetric analysis (TGA), rapid visco analyser and differential scanning calorimetry (DSC). Wheat flour, sugar and fat/oil were the main ingredients used to produce basic dough of semi-sweet biscuit for this study. Semi-sweet biscuit dough formulations with varying types of oils namely palm oil, palm olein, palm stearine, sunflower oil and butterfat were developed. The final mass (i.e. the total amount of moisture lost) for the samples showed significant differences between the doughs; with the control dough, dough contained palm stearine and butter falling into one group and the butter, palm oil, palm olein and sunflower oil forming the second group that showed less mass loss. Doughs containing low levels of saturated fatty acids (palm olein, palm oil and sunflower oil) showed significant difference on the drying properties of samples compared to doughs containing high saturated fatty acids (palm stearine and butter) as revealed by TGA. Pasting properties result showed that oil with different saturation influenced peak viscosity obtained. The DSC results showed that sugar and oil increased the gelatinisation peak temperature up to 2 and 6 °C, respectively. Oils with low saturated fatty acids have more capability to make contact with starch granules during the mixing processing as compared to oil with a high level of saturated fat. It is suggested that the oil presence in the system was delaying the drying process by coating the wheat flour particles hence slowing the drying process as compared to a sample without oil. 相似文献
This article reviews the available literature published to date on the reinforcement of metals with carbon-nanofillers (CNTs and graphene), and also offers a specific focus on issues related to the mechanical and tribological properties of nanocomposites. Carbon-nanofillers (later denoted by C-nanofillers) are known to have extraordinary mechanical properties and multifaceted characteristics and are ideal candidates for the reinforcement of metals for numerous applications. However, their incorporation for practical applications has been challenging researchers for decades. The most important issue is uniform dispersion due to sizeable surface differences between carbon-nanofillers and metals. Other concerns are structural integrity, wetting with metals, and interfacial connections. Nanocomposite applications can only be effective when these challenges are properly addressed and overcome.
Section 1 assesses the importance of C-nanofillers and expressly highlights current research efforts to optimize dispersion in different metals along with processing techniques in section 2. The authors give special attention on C-nanofillers reinforcement contribution to enhanced mechanical strength of metals presented in section 3. C-nanofillers dispersion evaluation tools are highlighted in section 4. Authors also focuses on C-nanofillers role and factors directly associated with metal nanocomposite strength, as reported in the literature. Particular consideration is also given to knowledge sharing of attendant strengthening mechanisms along with contribution reported for empirically derived models used to predict strength. Section 6 solely dedicated to the tribological aspects of C-nanofillers reinforced metallic nanocomposites. Lastly, future recommendations and works need attention is summarized. 相似文献
A two-dimensional numerical solution for pulsed laser transformation hardening is developed using the finite difference method (FDM). The FDM has been developed using Crank-Nicolson scheme which solved by using alternating-direction implicit method. If this present model was compared to the analytical solution, then the Crank-Nicolson scheme showed better results in terms of accuracy, consistency, stability, convergence, and performance than to the explicit scheme. The longer heating duration, higher laser beam intensity, and greater number of pulse had influences on increasing the maximum temperature. The repetitive heating had influences on extending the heat duration and increasing the initial temperature of domain. The shorter cooling duration in repetitive pulse produced higher maximum temperature. The thinner material’s thickness increased the cooling rate, which finally increased the possibility of austenite to transform into martensite phase. In addition, it was also found that the higher maximum temperature always reduced the cooling rate value when temperature cools down toward to the starting temperature of martensite formation. It reduced the possibility of martensite formation. It was also seen that the heat was conducted more effective to the axial direction than to the radial direction. 相似文献
In this study, a molybdenum disulfide/multiwalled carbon nanotubes (MoS2@MWCNTs) nanocomposite was synthesized by employing a simple hydrothermal method. The flower‐like structure of the MoS2@MWCNTs was characterized via scanning electron microscopy (SEM) and transmission electron microscopy (TEM), and the load of crystalline MoS2 was verified via X‐ray diffraction (XRD) and energy‐dispersive spectroscopy (EDS). The as‐prepared MoS2@MWCNTs nanocomposite was used to modify glassy carbon electrode (GCE) as an electrochemical sensor for detecting aristolochic acids (AAs). With the optimized parameters, the proposed electrochemical sensor exhibited good sensitivity and a broad linear concentration range for detecting AAs from 0.2 to 10 μ mol/L and 10 to 100 μ mol/L, with the sensitivity of ?3.10 μ A/(μ mol/L) and ?0.91 μ A/(μ mol/L), respectively. The detection limit was also calculated as 0.06 μ mol/L (S/N=3) based on the low background signal. Furthermore, the modified electrochemical sensor exhibited good selectivity, repeatability, reproducibility, and stability, thus showing potential application for detecting AA in chinese herbs with good mean recovery and accuracy. In other words, the MoS2@MWCNTs/GCE can be used as an excellent platform to detect AAs. 相似文献
Two sets of functionalised calix[4]arenes, either with a 1,3-crown ether bridge or with an open-chain oligo ether moiety in 1,3-position were prepared and further equipped with additional deprotonisable sulfonamide groups to establish chelating systems for selected cations Sr2+, Ba2+, and Pb2+ ions. To improve the complexation behaviour towards these cations, calix[4]arenes with oligo ether groups and modified crowns of different sizes were synthesized. Association constants were determined by UV/Vis titration in acetonitrile using the respective perchlorate salts and logK values between 3.2 and 8.0 were obtained. These findings were supported by the calculation of the binding energies exemplarily for selected complexes with Ba2+. 相似文献