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To enhance the resistant starch (RS) content of corn starch, in this work, carboxymethyl chitosan/corn starch/sodium alginate microcapsules (CMCS/CS/SA) with varying concentrations of SA in a citric acid (CA) solution were designed. As the SA concentration increased from 0.5% to 2%, the swelling of the CMCS/CS/SA microcapsule decreased from 15.28 ± 0.21 g/g to 3.76 ± 0.66 g/g at 95 °C. Comparatively, the onset, peak, and conclusion temperatures (To, Tp, and Tc) of CMCS/CS/SA microcapsules were higher than those of unencapsulated CS, indicating that the dense network structure of microcapsules reduced the contact area between starch granules and water, thereby improving thermal stability. With increasing SA concentration, the intact and dense network of CMCS/CS/SA microcapsules remained less damaged after 120 min of digestion, suggesting that the microcapsules with a high SA concentration provided better protection to starch, thereby reducing amylase digestibility. Moreover, as the SA concentration increased from 0.5% to 2%, the RS content of the microcapsules during in vitro digestion rose from 42.37 ± 0.07% to 57.65 ± 0.45%, attributed to the blocking effect of the microcapsule shell on amylase activity. This study offers innovative insights and strategies to develop functional starch with glycemic control properties, holding significant scientific and practical value in preventing diseases associated with abnormal glucose metabolism. [ABSTRACT FROM AUTHOR]

With the development of China's financial market, the risk contagion effect among financial institutions is increasing and becoming more complicated. Few literatures have explored the risk transmission paths of Chinese financial institutions at different frequencies. In order to make up for the gaps in this research field, variable mode decomposition (VMD) technology is introduced in this paper, combined with the Copula-GARCH model to construct the GARCH-VMD-Copula-CoVaR model, which describes the risk contagion paths of major financial institutions in the Chinese financial market at different frequencies (long-term, medium-term and short-term). The research results show that risk dependence and contagion between financial institutions have the characteristics of bidirectionality, asymmetry and time-varying in all frequency studies, and there are differences in different frequencies. [ABSTRACT FROM AUTHOR]

An important feature of the outbreak of systemic financial risk is that the linkage and contagion of risk amongst the various sub-markets of the financial system have increased significantly. In addition, research on the prediction of systemic financial risk plays a significant role in the sustainable development of the financial market. Therefore, this paper takes China's financial market as its research object, considers the risks co-activity among major financial sub-markets, and constructs a financial composite indicator of systemic stress (CISS) for China, describing its financial systemic stress based on 12 basic indicators selected from the money market, bond market, stock market, and foreign exchange market. Furthermore, drawing on the decomposition and integration technology in the TEI@I complex system research methodology, this paper introduces advanced variational mode decomposition (VMD) technology and extreme learning machine (ELM) algorithms, constructing the VMD-DE-ELM hybrid model to predict the systemic risk of China's financial market. According to eRMSE, eMAE, and eMAPE, the prediction model's multistep-ahead forecasting effect is evaluated. The empirical results show that the China's financial CISS constructed in this paper can effectively identify all kinds of risk events in the sample range. The results of a robustness test show that the overall trend of China's financial CISS and its ability to identify risk events are not affected by parameter selection and have good robustness. In addition, compared with the benchmark model, the VMD-DE-ELM hybrid model constructed in this paper shows superior predictive ability for systemic financial risk. [ABSTRACT FROM AUTHOR]

Large-scale hexagonal SnS2 flakes with high quality and tunable structures have been fabricated by an improved chemical vapor deposition method. The flakes follow a spiral growth mechanism and exhibit a two-dimensional structure with a large width-to-height ratio. Raman oscillation induced by laser interference has been observed on the flakes with a pyramid-shaped top. Based on the analysis on oscillatory period and height profile, the index of refraction for the grown SnS2 can be determined. SnS2 flakes with optimized structures have been further designed and prepared successfully, on which enhanced Raman emission can be obtained across the whole flake. [ABSTRACT FROM AUTHOR]

Monolayer MoS 2 in triangular configurations with rich edges or high-quality uniform films are either catalytically active for the hydrogen evolution reaction or flexible for functional electronic and optoelectronic devices. Here, we have experimentally discovered that these two types of MoS 2 products can be selectively synthesized on graphene or sapphire substrates, which are associated with both different adsorption energy and diffusion-energy barrier for vapor precursors during growth. Our study not only provides insights into the on-surface synthesis of high-quality MoS 2 monolayers, but also can be applied to the growth of vertically-stacked and large-scale in-plane lateral MoS 2 -graphene heterostructures.

We report on 976-nm diode-pumped Er:Y 2 O 3 ceramic lasers in continuous-wave and passively Q-switched regimes. The maximum output power of continuous-wave laser operation is about 0.78 W with slope efficiency of about 11.8% at 2.7 μm. Passively Q-switched Er:Y 2 O 3 ceramic laser operation with chemical vapor deposition (CVD) graphene as the saturable absorber is also demonstrated for the first time, to our knowledge. Using a monolayer CVD graphene, the achieved shortest pulse width is about 408 ns, while the shortest pulse width reduces to about 296 ns with pulse energy of 2.59 μJ and peak power of 8.77 W by using a three-layer CVD graphene. The results reveal that graphene is a very promising saturable absorber operating in the middle infrared spectral region.

Other than the well-known sulfurization of molybdate compound to synthesize molybdenum disulfide (MoS 2 ) layers, the dynamic process in the whole crystalline growth from nuclei to triangular domains has been rarely experimentally explored. Here, a competing sulfur-capture principle jointly with strict epitaxial mechanism is first proposed for the initial topography evolution and the final intrinsic highly oriented growth of triangular MoS 2 domains with Mo or S terminations on the graphene (Gr) template. Additionally, potential distributions on MoS 2 domains and bare Gr are presented to be different due to the charge transfer within heterostructures. The findings offer the mechanism of templated growth of 2D transition metal dichalcogenides, and provide general principles in syntheses of vertical 2D heterostructures that can be applied to electronics., (© 2017 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.)