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Both the increasing salinity levels and the decline of submerged macrophytes represent growing concerns in global freshwater ecosystems, posing a threat to water quality and various aquatic organisms. However, there is a limited understanding of the interactive effects of salinity and submerged macrophytes on zooplankton and benthic Ostracoda in tropical zones. To address this knowledge gap, we conducted a controlled experiment spanning 6 months, comparing the biomass of zooplankton (including copepods, cladocerans, and rotifers) and benthic Ostracoda in mesocosms with three levels of salinity, at the presence or absence of submerged macrophytes. Our results showed that in tropical zones, both zooplankton and benthic Ostracoda biomass exhibited a noteworthy decrease in response to increasing salinity, but the presence of submerged macrophytes did not have a significant influence on the zooplankton biomass. However, the presence of submerged macrophytes had a positive effect on the benthic Ostracoda biomass. Interestingly, submerged macrophytes had a strong interaction with salinity on the Ostracoda biomass, which increased with macrophyte presence under intermediate salinity conditions (2 g/L). In summary, our study sheds light on the interplay between salinity, submerged macrophytes, and the biomass of zooplankton and benthic Ostracoda in tropical freshwater ecosystems. [ABSTRACT FROM AUTHOR]

This study explores the dynamics of emerging technology innovation ecosystems, viewing them as complex systems comprising social actors and knowledge artifacts engaged in innovation interactions. Employing a multilayer network perspective, we present a Social-Knowledge-Science-Technology (A-K-S-T) framework, examining both homogeneous and heterogeneous interactions among innovators and knowledge elements. Within this framework, we map out the technological landscape, identify ecological niches for specific actors and knowledge elements, and gauge knowledge proximity among innovators, revealing opportunities for collaboration and knowledge innovation. Using 5G technology as an illustrative example, key findings include the potential for innovation development in 5G, the need for enhanced collaboration among organizations in related technological fields, and the complementary nature of scientific and technological knowledge. This research contributes to innovation ecosystem literature, offering insights for management, governance, efficiency, and shared prosperity; meanwhile, it is a valuable reference for decision-makers to shape effective strategies. [ABSTRACT FROM AUTHOR]

Tunable Diode Laser Absorption Spectroscopy (TDLAS) has been widely applied in in situ and real-time monitoring of trace gas concentrations. In this paper, an advanced TDLAS-based optical gas sensing system with laser linewidth analysis and filtering/fitting algorithms is proposed and experimentally demonstrated. The linewidth of the laser pulse spectrum is innovatively considered and analyzed in the harmonic detection of the TDLAS model. The adaptive Variational Mode Decomposition-Savitzky Golay (VMD-SG) filtering algorithm is developed to process the raw data and could significantly eliminate the background noise variance by about 31% and signal jitters by about 12.5%. Furthermore, the Radial Basis Function (RBF) neural network is also incorporated and applied to improve the fitting accuracy of the gas sensor. Compared with traditional linear fitting or least squares method (LSM), the RBF neural network brings along the enhanced fitting accuracy within a large dynamic range, achieving an absolute error of below 50 ppmv (about 0.6%) for the maximum 8000 ppmv methane. The proposed technique in this paper is universal and compatible with TDLAS-based gas sensors without hardware modification, allowing direct improvement and optimization for current optical gas sensors. [ABSTRACT FROM AUTHOR]

Photoacoustic spectroscopy (PAS) has received extensive attention in optical gas sensing due to the advantages of high sensitivity, gas selectivity, and online detection. Here, a mid-infrared hollow-core fiber (HCF) based flexible longitudinal photoacoustic resonator for PAS-based gas sensing is proposed and theoretically demonstrated. A mid-infrared anti-resonant HCF is designed to innovatively replace the traditional metallic acoustic resonator and obtain a flexible photoacoustic cell in PAS. Optical transmission characteristics of the HCF are analyzed and discussed, achieving single mode operation with below 1 dB/m confinement loss between 3 and 8 μm and covering strong absorptions of some hydrocarbons and carbon oxides. With varied bending radii from 10 mm to 200 mm, the optical mode could be maintained in the hollow core. Based on the photoacoustic effect, generated acoustic mode distributions in the HCF-based flexible photoacoustic resonator are analyzed and compared. Results show that the PAS-based sensor has a stable and converged acoustic profile at the resonant frequency of around 16,787 Hz and a favorable linear response to light source power and gas concentration. The proposed novel photoacoustic resonator using HCF presents bring potential for advanced flexible PAS-based gas detection. [ABSTRACT FROM AUTHOR]

Ca-alginate beads have strong hygroscopicity, which have been used for the self-healing and internal curing of cement-based materials. However, ca-alginate beads in cement will chelate with calcium ions, which decreases the swelling rate of ca-alginate beads in the healing environment and is detrimental to the self-healing of cement-based materials. In this paper, the mechanism and steps for preparing ca-alginate beads with a lower ability to chelate with calcium ions were proposed based on protonation theory. In addition, the molecular structure and the swelling rates in cement filtrate and healing environment of ca-alginate beads prepared by the proposed method were characterized. The results showed that the ca-alginate beads prepared by the proposed method had higher molecular density and a lower ability to chelate with calcium ions. The swelling rate in the healing environment is not decreased. Furthermore, the equilibrium swelling rate in cement filtrate can satisfy the need for internal curing of cement-based materials. [ABSTRACT FROM AUTHOR]

The traditional brick bungalow is not conducive to long-term grain storage because of its poor thermal insulation. In this paper, a new type of wall element for grain bungalows with both load-carrying and thermal insulation functions, called a "Structure-Insulation" integrated wall panel (SIW), is proposed for improving the grain storage environment. To study the thermal insulation reliability of SIW under multivariable randomness and the availability of different grain storage zones, a finite element model was established based on the test. Then, the failure criterion was established with the heat transfer coefficient as the key point and 1,000,000 sampling calculations were carried out by the Monte Carlo method. The reliability was discussed and sensitivity of random parameters was quantified. The thermal performance test shows that the heat transfer coefficients of the two designed SIW wall panels compared with the traditional brick bungalow wall are reduced by 45.81% and 56.13%, respectively. The thickness of the insulation panel is sensitive mostly to the thermal insulation performance, with a correlation coefficient of 0.877. When the thickness of the insulation panel is 80, 94, and 107 mm, the wall panel can meet the limit requirements of the heat transfer coefficient of the granary enclosure structure of 0.59, 0.53, and 0.46 W / m 2 · K , with reliability indexes of 3.08, 1.82, and 1.75, respectively. The research results provide an important reference for the design, optimization, and application of SIW wall panels in thermal insulation. [ABSTRACT FROM AUTHOR]

Calcite is often doped with impurity ions that affect its dissolution behavior. In the present investigation, solid solutions of (Ca, Mn)CO3 and (Ca, Cu)CO3 were synthesized by coprecipitation to study their dissolution in an acidic solution (pH = 5) at 25 °C. The solution chemical analysis results showed that the concentrations of aqueous Cu2+ and Mn2+ first increased and then decreased with the extension of dissolution time. Scanning electron microscope (SEM) and transmission electron microscope (TEM) observations revealed that rhodochrosite (MnCO3) and malachite (Cu2(OH)2CO3) formed during the dissolution. This suggested that the impurities in calcite might impact the dissolution and precipitation of carbonates in the environment. [ABSTRACT FROM AUTHOR]