Fraudulence in cosmetic ingredients is becoming increasingly prevalent, alongside the rising demand and utilization of cosmetics within the populace. One of the whitening agents still utilized in cosmetics is mercury, present in forms such as mercury chloramide (HgNH2Cl2) and mercury chloride (HgCl2). Prolonged mercury exposure can have adverse health effects. To address this issue, alternative mercury analysis methods in samples have been developed, including the utilization of silver nanoparticles amalgamated with sweet potato starch as a stabilizing agent. This paper aims to delve into the roles of silver nanoparticle AgNO3 and sweet potato starch (as a stabilizer) as a sensor for mercury detection, which can be applied in cosmetic products. Detection of mercury utilizing nanoparticles is based on the Surface Plasmon Resonance phenomenon, which endows a high level of selectivity and sensitivity toward the presence of mercury metal ions. When interaction occurs between mercury metal and silver nanoparticles, the liquid undergoes a color change from yellowish-brown to transparent. This phenomenon arises from the oxidation of AgO (yellow) to Ag+ ions (transparent) by the mercury metal. Consequently, a silver nanoparticle sensor utilizing sweet potato starch as a stabilizing agent exhibits the potential to detect mercury metal within a substance with high efficacy.
Our study evaluated the effect of vanadium (V) on the behavior of Zinnia elegans “double variegated”. In this experiment, Zinnia plants grown in a greenhouse were fed with a nutrient solution and two concentrations of vanadium (0, 6, and 10 μm) applied four times during the experiment. The V at its levels of 6 µm and 10 µm increased plant length, number of inflorescences and fresh weight. We observed that during the development and appearance of flower buds, and flowering were earlier with the addition of 6 µm and 10 µm. During harvest the changes in size and shape were homogeneous with the control treatment. With the addition of 6 µm, flowers of different sizes were induced, with non-uniform petals, but with different shades of color. With 10 µm the shape of the petals, the distance between them and changes in the shades of the flowers were modified. The postharvest life for the flowers of the control treatment was shorter (15 days), the petals, anthers and floral disc at this time were observed in a poor condition. While 6 µm and 10 µm had a longer postharvest life (20 days), the flowers had a good presentation, their colors were more intense compared to the harvest stage. The application of this beneficial element contributed to the development and flowering of Zinnia in the greenhouse. It is suggested that future research be carried out on the accumulation and/or concentration of vanadium in the different stages of growth or its effect on the concentration of other nutrients.
Taking the 13 years pure artificial forest Phoebe chekiangensis and heterogeneous mixed forests in Tiantong mountain, Zhejiang Province as the research object, the characteristics of stand development, tree competition differentiation, tree height/breast diameter ratio and dominant wood growth were compared and analyzed from the perspective of ecology. The results show that compared with pure forests, the growth advantages of heterogeneous mixed-age forests were significant. Average breast diameter growth of stand increased 1.8%; the growth of single plant wood accumulation increased 7.4%. The relationship between tree height and diameter showed that the high growth of Phoebe chekiangensis individuals in the heterogeneous mixed forest was significantly promoted, and the high growth of the tree was 8.4% higher than that of pure forest. 1–5 grade wood scale sizes Phoebe chekiangensis in heterogeneous mixed forests and pure forests are ranked grade 3 (43.7%) > grade 2 (26.5%) > grade 4 (15.7%) > grade 1 (12.9%) > grade 5 (1.2%); grade 3 (34.7%) > level 2 (25.6%) > level 4 (20.0%) > level 1 (18.2%) > level 5 (1.2%); the straight-diameter structure shows a normal distribution, and the degree of differentiation of pure forests is greater than that of heterogeneous forests. The dominant trees of Phoebe chekiangensis pure forest and heterogeneous forest accounted for 18.2% and 12.9% of the total number of plants respectively, providing a reserve of 51.1% and 35.4% respectively, reflecting the contribution of dominant trees caused by the self-thinning effect.
This paper presents the state of displacement of a multilayered composite laminate subjected to transverse static load with varying balance, symmetric and anti-symmetric angle-ply and cross-ply staking sequences. Higher-order shear deformation theory (HSDT) is considered in the finite element formulation of nine-noded isoparametric element with seven degrees of freedom at each node. The finite element formulation is transformed into computer codes. A convergence study is carried out first to obtain the optimal mesh size for minimizing the computational time. The maximum deflection at the center of plate for both fixed and simply supported edges is verified with reported literature and a good conformity is found. An attempt has been made to observe the minimum value of maximum deflection in the laminate for attaining the maximum strength of laminate with a suitable combination of stacking sequences with a constant volume of material.
One functional class is described in terms of one-sided modulus of continuity and the modulus of positive (negative) variation on which there
is a uniform convergence of the truncated cardinal Whittaker functions.
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