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Metal–organic frameworks (MOFs) have shown great research and application value in various types of hydrosilylation reactions. However, studies on photocatalysis‐induced hydrosilylation using MOFs are extremely rare. Metal nanoparticles (MNPs)@MOFs are extensively studied for their excellent structural tunability and photocatalytic activity, but there are few reports on their application in photocatalytic hydrosilylation. Here, a novel photocatalyst consisting of platinum (Pt) nanoparticles immobilized in a MOF framework is synthesized and used for photocatalytic hydrosilylation. The effects of various factors on hydrosilylation conversion are investigated, including catalyst concentration, substrate ratio, and irradiation intensity. Furthermore, the photoreactivity of the synthesized Pt catalyst is evaluated in the presence of different concentrations of 2‐chlorothixanthone as a photosensitizer. It is noteworthy that the conversion of the reaction increases with increasing catalyst concentration or photosensitizer concentration, whereas increasing the polymethylhydrosiloxane content does not lead to a significant increase in conversion. This study demonstrates the potential of MNPs@MOFs as efficient photocatalysts for photoinduced hydrosilylation reactions and paves the way for future applications in this area. [ABSTRACT FROM AUTHOR]

Covalent organic frameworks (COFs) are an emerging class of porous crystalline polymers with well‐defined structures and tunable functionalities, which have fascinating applications in a wide range of fields. However, the synthetic procedures of COFs are mainly confined to the solvothermal synthesis method which usually requires harsh experimental conditions. In this work, an effective solvent‐free synthesis method to construct a series of two‐dimensional (2D) COFs including imine‐linked, azine‐linked, β‐ketoenamine‐linked, which avoids the complicated solvent screening process and most of the disadvantages of solvothermal methods is developed. The crystallinity and porosity of these COFs are comparable to those prepared by traditional solvothermal routes. What's more, the advantages of the solvent‐free method enable the production of gram‐scale of those 2D COFs through a one‐pot reaction, demonstrating high industrial application potentials. [ABSTRACT FROM AUTHOR]

The intellectual properties (IP) protection of deep neural networks (DNN) models has raised many concerns in recent years. To date, most of the existing works use DNN watermarking to protect the IP of DNN models. However, the DNN watermarking methods can only passively verify the copyright of the model after the DNN model has been pirated, which cannot prevent piracy in the first place. In this paper, an active DNN IP protection technique against DNN piracy, called ActiveGuard, is proposed. ActiveGuard can provide active authorisation control, users' identities management, and ownership verification for DNN models. Specifically, for the first time, ActiveGuard exploits well‐crafted rare and specific adversarial examples with specific classes and confidences as users' fingerprints to distinguish authorised users from unauthorised ones. Authorised users can input their fingerprints to the DNN model for identity authentication and then obtain normal usage, while unauthorised users will obtain a very poor model performance. In addition, ActiveGuard enables the model owner to embed a watermark into the weights of the DNN model for ownership verification. Compared to the few existing active DNN IP protection works, ActiveGuard can support both users' identities identification and active authorisation control. Besides, ActiveGuard introduces lower overhead than these existing active protection works. Experimental results show that, for authorised users, the test accuracy of LeNet‐5 and Wide Residual Network (WRN) models are 99.15% and 91.46%, respectively, while for unauthorised users, the test accuracy of LeNet‐5 and WRN models are only 8.92% and 10%, respectively. Besides, each authorised user can pass the fingerprint authentication with a high success rate (up to 100%). For ownership verification, the embedded watermark can be successfully extracted, while the normal performance of DNN models will not be affected. Furthermore, it is demonstrated that ActiveGuard is robust against model fine‐tuning attack, pruning attack, and three types of fingerprint forgery attacks. [ABSTRACT FROM AUTHOR]

Summary: Antimicrobial photodynamic therapy (aPDT) is an effective method in the field of sterilisation. Singlet oxygen (1O2) is an important substance in photodynamic sterilisation that needs to be detected. It involves energy transfer from an excited photosensitiser to surrounding oxygen molecules to produce cytotoxic 1O2 species, a process termed as type II reaction. Traditional photodynamic sterilisation for fresh produce generally involves only a single photosensitiser and uses nanoemulsions coating to make the photosensitiser work better. This allows the emulsion to produce only a limited amount of reactive oxygen species (ROS) in the presence of light, such that the bactericidal effect is limited. We have innovatively compounded two photosensitisers and stored them as nanoemulsions. The composite photosensitiser produces relatively higher ROS and the nanoemulsions have good stability as well as rheological properties, and the photosensitisers are well coated in the emulsions. In summary, nanoemulsions based on composite photosensitisers showed synergistic activity in controlling the growth of Staphylococcus aureus, which provides a novel approach for raw sterilisation to maintain food safety. [ABSTRACT FROM AUTHOR]

Gas separation technology is one of the difficulties in the chemistry and purification industry. To help solve this problem, we have prepared mixed matrix membranes containing Zr‐based metal‐organic framework (MOF), ethyl cellulose (EC) and polyimide (PI), and characterized them by FTIR, SEM and gas separation measures. The obtained mixed matrix membranes have good mechanical and thermal properties, the tensile strength of mixed matrix membranes improved by 5.44‐10.5 times compared to pure EC membrane. Especially, the mixed matrix membranes exhibited excellent CO2 permeability compared to pure EC and pure PI membranes. CO2 permeability of mixed matrix membrane contained 15 % MOF was 145.5 Barrer and the CO2/CH4 permselectivity was 11.95, which increased 2.21 times and 0.45 times compared to pure EC membrane. Comparison with 1991 and 2008 Robeson Upper Bound, the mixed matrix membranes were closer to the Robeson Upper Bound than pure EC membrane. [ABSTRACT FROM AUTHOR]

Significant improvement of soil quality and biodiversity has been reported following vegetation restoration on the degraded lands in subtropical of China. However, so far the response of soil bacterial communities and drivers of their composition to differing vegetation restoration types are not well understood. In this study, we investigated soil physicochemical properties and bacterial communities in degraded land subjected to differing vegetation restoration types after 12 years of long‐term experiment. Restoration types included grassland, cropland, three differing plantation forests (orchard, coniferous forest, and coniferous forest with applied tillage), and control of degraded land. Bacterial community composition was examined using 16S rDNA sequencing. Result found that soil nutrient content includes soil organic carbon (SOC), total N (TN), available nitrogen (AN), available phosphorus (AP), and available potassium (AK) was improved after 12‐year restoration and the highest contents were found in cropland. However, soil pH was decreased after revegetation in the order degraded land > grassland > forestland > cropland, and the soil C/N ratio was significantly decreased in cropland. Revegetation restoration significantly increased operational taxonomic units (OTUs), ACE, and Chao1 indices by 13.67–22.81%, 16.34–25.11%, and 14.66–24.00%, with relative abundances of bacterial phyla varying between the different vegetation types. Soil physicochemical properties (e.g. pH, SOC, TN, AN, AP, and AK) showed significant correlations with the majority of the dominant phyla. When degraded land was restored to cropland, soil C/N ratio decreased which promoted the growth of Actinobacteria. Revegetation with grassland and forest increased soil nutrient content and decreased pH, resulting in shifts in bacterial phyla favoring Proteobacteria and Acidobacteria. Our observations show that restoration of degraded land will lead to differing bacterial community compositions depending on the vegetation type. [ABSTRACT FROM AUTHOR]

The lead‐acid battery has been widely used in various fields. In civil aviation aircraft, it plays a vital role in the power system to maintain normal operation during the flight mission. Thus, an effective abnormal detection system for monitoring and diagnosing the status of aircraft lead‐acid battery is essential to ensure its safety and reliability. This paper aims to effectively identify aircraft battery faulty using unsupervised anomaly detection techniques. It introduces state‐of‐the‐art anomaly detection algorithms and evaluates their performance on a large real civil aviation battery data. The experimental results show that the latest isolation‐based anomaly detectors, iForest and iNNE, have outstanding performance on this task and have promising applicability as efficient methods for guaranteeing the lead‐acid battery quality and reliability in civil aviation aircraft. [ABSTRACT FROM AUTHOR]

To promote the awareness of Priestley–Taylor (PT) model and extend the knowledge of hydrological model under snow, performance of PT model was illustrated by comparing with eddy covariance (EC) measurements over a temperate meadow. The results showed that the mean half‐hourly averages and directly calculated daily value of PT parameter α is 0.47 ± 0.27 and 0.51 ± 0.32, respectively. Vapour pressure deficit VPD is the mainly factor influences α in the snow‐covered period, while soil moisture in the snow‐free period. PT method underestimated evaporation in the whole study period and showed remarkable difference in different phases. It performed best in the snow‐melting phase, better in the presnow phase, worse in the fresh snow phase and worst in the snow‐melted phase. These studies indicated that PT model could be used to estimate evaporation over temperate meadow in dormant season, but utility of a variable PT parameter α during different phases should be considered. [ABSTRACT FROM AUTHOR]

Three methods of calculating evapotranspiration (ET), Penman–Monteith (PM), Makkink (MK) and Priestley–Taylor (PT) equation, were applied to a temperate meadow in Inner Mongolia, China. We compared these methods with eddy covariance (EC) method. The results indicated that a reduction in mean absolute error (MAE) and root mean squared error (RMSE) was achieved for MK and PT methods (45.6–83.0%) when using site‐specific parameters compared with referenced ones, but an increase of 75.9–93.9% for PM method. Intercomparison of three methods through comparison with EC measurements indicated that PT method with site‐specific parameters performed the best to estimate ET, followed by PM method with referenced parameters, and then MK equation with site‐specific parameters (overestimate ET by 8.2, 12.1, 16.5% and 3.4, 12.8, 21.0% respectively for half‐hourly and daily values). [ABSTRACT FROM AUTHOR]

Abscisic acid ( ABA) glucose conjugation mediated by uridine diphosphate glucosyltransferases ( UGTs) is an important pathway in regulating ABA homeostasis. In the present study, we investigated three tomato Sl UGTs that are highly expressed in fruit during ripening, and these Sl UGTs were localized to the cytoplasm and cell nucleus. Among these three UGTs, Sl UGT75C1 catalyzes the glucosylation of both ABA and IAA in vitro; Sl UGT76E1 can only catalyze the conjugation of ABA; and Sl UGT73C4 cannot glycosylate either ABA or IAA. Therefore, Sl UGT75C1 was selected for further investigation. Sl UGT75C1 RNA interference significantly up-regulated the expression level of Sl CYP707A2, which encodes an ABA 8′-hydroxylase but did not affect the expression of Sl NCED1, which encodes a key enzyme in ABA biosynthesis. Suppression of Sl UGT75C1 significantly accelerated fruit ripening by enhancing ABA levels and promoting the early release of ethylene. Sl UGT75C1- RNAi altered the expression of fruit ripening genes (genes involved in ethylene release and cell wall catabolism). Sl UGT75C1- RNAi seeds showed delayed germination and root growth compared with wild-type as well as increased sensitivity to exogenous ABA. Sl UGT75C1- RNAi plants were also more resistant to drought stress. These results demonstrated that Sl UGT75C1 plays a crucial role in ABA-mediated fruit ripening, seed germination, and drought responses in tomato. [ABSTRACT FROM AUTHOR]

A new image encoding scheme for simultaneous encryption and compression applications, which is based on random convolution and random subsampling, is proposed. In comparison with the existing joint optical encryption and compression schemes tailored for multiple images, the proposed scheme can process a single image and achieve a robust reconstruction. The scheme with the architecture of double random masks is somewhat similar to double random phase encoding. However, the latter has no compression capability and the proposed scheme remedies this defect. [ABSTRACT FROM AUTHOR]

An improved version of Li et al.'s method of reversible data hiding of encrypted images is proposed. The original work partitions the encrypted image into two sets, and only one set is used for data embedding. After carrying out a feasibility analysis, the full embedding strategy is employed. Accordingly, the data embedding capacity is dilated. In addition, the corresponding new fluctuation measurement is designed for the full embedding strategy. The experimental results reveal that the full embedding strategy is effective and also indicate that using the new fluctuation measurement the performance is further augmented. The proposed method outperforms other works in terms of performance. [ABSTRACT FROM AUTHOR]