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Background Hydrogen (H2) is viewed as a clean, green, and sustainable energy source. The photocatalytic H2 evolution using light-activated photocatalyst under light irradiation is attractive to convert light into chemical energy in a feasible way. In the present work, photocatalysis of H2 generation was explored, using graphitic carbon nitride (g-C3N4) synthesized from freeze-dried dicyandiamide (DICY). Methods The DICY underwent rapid dissolution-recrystallization during the freeze-drying process, enabling more complete polymerization of the heptazine units of g-C3N4 than occurred in the same compound synthesized from untreated DICY. After loading with Pt as a cocatalyst, and under light irradiation (metal halide lamp) in the presence of triethanolamine, g-C3N4 synthesized from freeze-dried DICY (DCN) showed an increased H2 evolution rate (∼20 μmol h‒1) compared with that using g-C3N4 derived from untreated DICY (CN) (12 μmol h‒1). In addition, DCN had a higher H2 generation rate than CN under light of different wavelengths (400, 450, and 550 nm). Significant Findings The improved activity of DCN could be attributed to inhibition of charge recombination (evidenced by photoluminescence), fast charge transfer (evidenced by electrochemical impedance spectra and photocurrent measurements), and a suitable energy bandgap (evidenced by Mott-Schottky and UV–vis measurements) resulting from better-polymerized heptazine rings (evidenced by nuclear magnetic resonance spectroscopy). In summary, DCN prepared in this study could be used as a visible-light activated and effective metal-free material for photocatalytic H2 generation.

The metal-organic framework UiO-66-NO2 was synthesized and was converted to amorphous mesoporous matrix by arsenate and phosphate modification. The 10 mM phosphate or arsenate solutions immersed for 120 min replaced 20% of zirconium cluster with partial deterioration of the crystalline structures at reduced surface areas and pore sizes which had lowered zeta potentials. The 50 mM arsenate or phosphate modification led to nearly complete replacement of zirconium clusters with total conversion into amorphous mesoporous matrix with low surface areas and enlarged internal pores, and further reduced surface zeta potentials in waters. The yielded matrix was tested on the adsorption capacity of lead ions from neutral waters.

Growth-regulating factor (GRF) is a transcription factor unique to plants that plays a crucial role in the growth, development and stress adaptation of plants. However, information on the GRFs related to salt stress in Populus davidiana × P. bolleana is lacking. In this study, we characterized the activity of PdbGRF1 in transgenic Populus davidiana × P. bolleana under salt stress. qRTPCR analyses showed that PdbGRF1 was highly expressed in young leaves and that the pattern of PdbGRF1 expression was significantly changed at most time points under salt stress, which suggests that PdbGRF1 expression may be related to the salt stress response. Moreover, PdbGRF1 overexpression enhanced tolerance to salt stress. A physiological parameter analysis showed that the overexpression of PdbGRF1 significantly decreased the contents of hydrogen peroxide (H

Cu–Zn alloy micropillars were fabricated using microanode-guided electroplating (MAGE) at a constant voltage of 4.6 V under an initial inter-electrode gap of 30 µm in pyrophosphate baths. Energy-dispersive spectroscopy and X-ray diffractometry analysis revealed that the micropillar alloys exhibit an increase in the Zn content from 8.05 at.% (in α phase) to 54.60 at.% (in β, and β' phases) with an increase in the ratio of [Zn2+]/[Cu2+] in the bath from 8/1 to 128/1. Transmission electron microscopy revealed that the Cu–Zn alloy micropillars were composed of nano-grains with different sizes depending on the bath employed. Nano-indentation test indicated that the micropillar containing 40.51 at.% Zn (in presence of β-phase) exhibits the maximum hardness (at 5.30 GPa) and highest Young's modulus (at 113.64 GPa). Simulation of the electric field using the commercial software COMSOL 5.2 revealed that the highest field strength centralized at the cylindrical top displayed only a slight increase (from 152.2 to 152.5 kV/m) with an increase in the ratio of [Zn2+]/ [Cu2+] in the bath. Potentiodynamic cathodic polarization is useful for understanding the mechanism of microanode-guided electroplating. Electrochemical impedance spectroscopy performed at characteristic potentials confirms the mechanism extremely well.

In this work, the feasibility of liquid level detection based on structural vibration modes is investigated. We specifically consider impact-induced vibration modes of an aluminum solid partially immersed in a water tank. A free-edge bonded fiber Bragg grating (FBG) sensor and a corresponding high-speed FBG filter-based demodulation system are employed to measure the transient impact responses. To perform more accurate in vacuo finite element analysis (i.e., for the mode shapes, resonant frequencies, and the impact responses), elastic constants of the aluminum solid and impact loading history of a steel ball are obtained beforehand respectively according to the elastic wave theory and with a polyvinylidene fluoride (PVDF)-based technique. Our experimental results show good correspondences of intensities and shifts of the impact-induced resonant modes with liquid levels. The modes of the same type (e.g., double modes in out-of-plane or in-plane dominated modes) are shown to possess similar behaviors in relationships between shifts of the resonant modes and the liquid level. This work also provides related experimental evidence for future researchers interesting in simulation of complicated fluid-structure interaction (FSI) problems for three-dimensional structures.

Emerging countries and traditional industries may not be ready for direct migration of Industry 4.0. In particular, the broiler is a major source for meat, while poultry farming in emerging countries is mainly by small and medium-sized enterprises (SMEs) or family businesses. The live broilers need to maintain the desired specification for food processing while optimizing the feeding conversion rate for revenue management. Conventionally, broiler growth monitoring and prediction rely on farmers’ experience and a small amount of data by unrigorous sampling. Although the automatic weighing system (AWS) has gradually been employed to replace manual weighing to reduce cost and casualties, existing automatic weighing systems have limited capability for weight monitoring and weight prediction of broiler future growth. To fill the gaps, this study aims to employ Industry 3.5 as a hybrid and develop a data-driven framework for weight monitoring and prediction to support smart production for poultry farming for revenue optimization. The proposed framework contains two modules. The weight monitoring integrates Gaussian Mixture Model, bootstrapping resampling, and weighted mean technique to estimate the current weight of live broilers in the farm via big data including electronic signals collected from the farms via multiple sensors and devices. The weight prediction module employs mathematical growth functions as a basis and daily feedback for adjustment to provide real-time weight prediction to support related decisions for smart production. An empirical study was conducted in Taiwan. The results have shown the practical viability of this approach. The developed solution is implemented in the broiler industry.

As the first step of DRAM manufacture, preanneal process plays an important role in determining the threshold voltage variation. It is found that the higher trans-1,2-dichloroethene flow in pad oxide growth and the higher nitrogen flow in high-temperature annealing step would respectively engender a lower boron segregation coefficient and higher nitridation of the oxide, both modify the boron distribution in the substrate and consequently the behavior of the threshold voltage. As the feature size of DRAM devices enter nanometer regime, besides gate oxidation, ion implantation and related thermal processes, the impact of preanneal process condition should be prudentially taken into consideration for rigorous control of the threshold voltage in the advanced DRAM production.

The influence of process condition on the resistivity of the arsenic-doped polysilicon electrode for the cell capacitors in trench DRAM was investigated. Rather than the arsine flow, it is found that the thickness of the undoped amorphous silicon plays a vital role in determining the overall resistivity. When the total polysilicon thickness is kept unchanged, moderately increasing the thickness of the lower two undoped amorphous silicon would engender a reduced resistivity while moving the arsenic peak location away from the polysilicon/storage dielectric interface, which is critical in leakage current suppression. With these improved properties, less bit line coupling (BLC) loss from the characterization on DRAM product is observed. The result of this study is quite important for trench DRAM manufacturer to enhance product yield before the technology of metal electrode is mature.