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The design and construction of Ag2S heterostructures capable of significantly separating photocarriers is a significant challenge in photocatalysis. In this study, CdS/Ag2S heterojunction composite photocatalyst is fabricated through a simple one‐step hydrothermal method. The composite structure is characterized by X‐ray diffraction, transmission electron microscopy, scanning electron microscopy, X‐ray photoelectron spectroscopy, and UV‐visible diffuse reflection spectroscopy. Under visible light irradiation, the photocatalytic activity of the sample is evaluated by degradation of methyl orange. The photoelectric chemical performance of the CdS nanoparticles modified by Ag2S is closely related to the ratio of Cd/Ag cation. The experimental results show that the sample ACS‐2 (CdS‐Ag2S = 1:1) composite has higher charge transfer/separation efficiency and longer carrier life. The degradation efficiency reaches 74.4% within 30 min, and the degradation rate constant is 0.047 min−1. After four cycles, the degradation efficiency of the catalyst only decreases slightly, indicating that the CdS/Ag2S catalyst has good stability and repeatability. Meanwhile, the study of the photocatalytic mechanism shows that •O1− is the primary active substance in the catalytic process, and h+ and •OH play a secondary role. This work provides a great significance for constructing efficient Ag2S‐based heterojunction photocatalyst systems. [ABSTRACT FROM AUTHOR]

Cellulose nanocrystals (CNCs) with high specific surface area, crystallinity, aspect ratio with unique rod-like shapes, elastic modulus and tensile strength are an excellent additive which can be used for the preparation of unique polymer/nanoparticle fiber composites from polymer solutions by electrospinning. Research on electrospinning as a technique has grown rapidly since 1990 with the number of publications increasing exponentially after 2005. The sudden increase in academic interest after 2005 was due to the electrospinning of various numbers of nanoparticles for diverse applications, including CNCs from polymer solutions. Although there are many preparation options and potential applications for using CNCs in electrospinning, the role of processing variables and interfacial interactions between CNCs, solvents and polymers must be fully understood before the desired objectives can be achieved. Since one of the unique features of CNCs is their modifiable surface chemistry, there are promising outcomes when using CNCs by tailoring CNCs/solvent and CBCs/polymer interfaces. We present a discussion that helps to show the whole process, including variables, of using CNCs as an electrospinning additive nanoparticle. We also discuss the existing and potential applications with different set ups. [ABSTRACT FROM AUTHOR]

An effective path to synthesize ZnxCd1‐xS quantum dots (ZCS QDs) in aqueous phase at room temperature has remained relatively unexplored. Here, we developed a room‐temperature, aqueous‐phase approach to ZCS QDs, using 3‐mercaptopropionic acid (MPA) to adjust the pH of the reaction precursor solution to regulate the competition between sulfur source and hydroxyl group, and realize the large‐scale preparation of water‐soluble ZCS QDs photocatalyst at room temperature. Without recombination with other materials, and only by regulating the ratio of pH, excess sulfur sources and Zn/Cd, the photocatalytic degradation of rhodamine B (RhB) can reach 98% within 1 min, showing high photocatalytic activity. ZCS QDs show high stability and recoverability, and are expected to be able to deal with organic pollutants on a large scale. This study provides a new idea for the preparation of other QDs at room temperature. [ABSTRACT FROM AUTHOR]

Direct Z-scheme photocatalytic systems driven by visible light to eliminate organic pollutants in wastewater have become important scientific tools in the field of photocatalysis. In this study, a direct Z-scheme CdIn2S4/TiO2 heterojunction with high efficiency was prepared through a simple hydrothermal method. Benefiting from the increased visible light response and prolonged lifetime of photoexcited carriers, the as-prepared CdIn2S4/TiO2 composites exhibit significantly promoted photocatalytic performance for the degradation of methyl orange (MO) under visible-light illumination (λ ≥ 420 nm). The CdIn2S4-25 wt% TiO2 (25CT) photocatalyst exhibited the highest degradation efficiency (96.2% within 30 min) with a rate constant of 0.1193 min−1 and remarkable stability and repeatability. In the meantime, the study of the photocatalytic mechanism shows that the charge transfer path conforms to the Z-scheme model, in which h+ and ˙O2− are the main active species. This study provides strong practical support for the preparation of efficient Z-scheme photocatalytic materials by hydrothermal methods. [ABSTRACT FROM AUTHOR]

Pyrolysis and gasification are considered as a means of producing renewable energy and improving energy sustainability, which has become attractive renewable technologies to many countries. Unlike other studies that are conducted in small scale, this study aims to aggregate the economic and environmental effects such as agricultural benefits, energy sale, and carbon sequestration to provide more detailed information to decision-makers before these projects are widely employed. This study first employs a lifecycle assessment to investigate the feasibility, profitability, and emission reduction of four major pyrolysis and gasification technologies using crop residuals, and then conducts a sensitive analysis to examine the most influential factors. The results indicate that the intermediate pyrolysis with rice straw and slow pyrolysis from corn stover could offset the carbon dioxide the most. However, the pyrolysis value is also sensitive to production of the feedstock used. Value adding of stover-based biochar under fast pyrolysis improves profitability but other technologies do not have such patterns. Additionally, while gasification can generate considerable amount of renewable electricity, it yields almost zero percent of biochar that can be used as a soil amendment, and thus its contribution to agricultural sector is trivial. [ABSTRACT FROM AUTHOR]

Among the 13 T1 plants analyzed, eight of them were quadruple mutants (Figure 1g), (ii) The gene-editing efficiency differed significantly among the four target genes (Figure 1g), (iii) I GENE1 i , I GENE2, i and I GENE3 i were not null in nine T1 plants of the TKC-M1 because they contained deletions of 3 or 9 bp. Editing gene families by CRISPR/Cas9: accelerating the isolation of multiple transgene-free null mutant combinations with much reduced labor-intensive analysis Keywords: CRISPR; transgene-free; multi; TKC; rice EN CRISPR transgene-free multi TKC rice 241 243 3 01/17/22 20220201 NES 220201 Genetically elucidating functions of gene families often requires simultaneous disruption of several family members to overcome redundancy. [Extracted from the article]

In this paper, we used machine learning algorithms such as k‐nearest neighbour, decision tree, gradient boosting decision tree, random forest, and support vector machine in a scikit‐learn module of Python to construct polarization curves and electrochemical impedance spectra. After application of this method to a high‐level nuclear waste disposal tank material of pure copper, the polarization curves, and electrochemical impedance spectra of pure copper under different chloride ion concentrations, sulfide concentrations, and temperature environments were used as training sets. The combination of the cross‐validation and experimental validation results revealed that the RF algorithm had the best effect on predicting the polarization curve and EIS. Through the input weight analysis, it was found that the sulfide concentration had the greatest influence on the polarization curve, followed by the chloride ion concentration, and the temperature influence was the smallest. For electrochemical impedance spectroscopy, sulfide and temperature had a large effect, while chloride ions had little effect. The result of the weight analysis was consistent with traditional electrochemical results. [ABSTRACT FROM AUTHOR]

An effective path to synthesize Zn x Cd 1-x S quantum dots (ZCS QDs) in aqueous phase at room temperature has remained relatively unexplored. Here, we developed a room-temperature, aqueous-phase approach to ZCS QDs, using 3-mercaptopropionic acid (MPA) to adjust the pH of the reaction precursor solution to regulate the competition between sulfur source and hydroxyl group, and realize the large-scale preparation of water-soluble ZCS QDs photocatalyst at room temperature. Without recombination with other materials, and only by regulating the ratio of pH, excess sulfur sources and Zn/Cd, the photocatalytic degradation of rhodamine B (RhB) can reach 98% within 1 min, showing high photocatalytic activity. ZCS QDs show high stability and recoverability, and are expected to be able to deal with organic pollutants on a large scale. This study provides a new idea for the preparation of other QDs at room temperature., (© 2021 Wiley-VCH GmbH.)