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Density functional theory (DFT) and Electrochemical Impedance Spectroscopy (EIS) were used to study the molecular adsorption behavior of the Co2+ doped TiO 2 (101) crystal plane, and the ethanol molecular gas sensitivity test was performed. Theoretical models indicate that doping leads to oxygen defects on the crystal plane and further chemisorption of two oxygen molecules, resulting in reduced electrical conductivity and improved oxygen storage capacity on the crystal plane. Ethanol molecules do not compete with N 2 , O 2 , and H 2 O molecules on doped crystal planes because of their different adsorption active sites, which means that the response time of gas-sensitive detection of ethanol molecules is short and is not interfered with the air molecules in the test environment. These results were confirmed by EIS and gas sensitivity experiments. The change of electrical conductivity after the adsorption of molecules on the crystal plane was confirmed by EIS. The enhanced oxygen storage capacity of the doped crystal plane was confirmed by the expansion of the linear response range of gas-sensitive detection from 20-100 ppm before doping to 20–1200 ppm. This provides a scientific basis for effectively shortening the gas-sensitive response time, increasing the concentration range, improving the oxygen-carrying capacity, and enhancing the catalytic and gas-sensitive properties of the material. [ABSTRACT FROM AUTHOR]

The gas-sensitive behavior of (221) and (110) crystal planes of SnO 2 to ethanol molecules were studied in this paper. The gas-sensitive detection results to 100 ppm ethanol showed that the response time of the (221) crystal plane is better than the (110) plane, which is 8 s and 62 s, respectively. The theoretical simulation shows that the gas-sensitive response time is determined by the adsorption speed of O 2 on the crystal plane. In the detection process of ethanol molecules, the O 2 molecules adsorbed on the crystal plane will be gradually consumed, causing the change of electrical conductivity on the crystal plane, to complete the gas sensitivity detection. In the air, N 2 , O 2 , and H 2 O molecules occupy the same active sites on the (110) crystal plane, and adsorption competition leads to the increased response time of gas-sensitive detection. However, the three molecules occupy different adsorption active sites on the (221) crystal plane, so the adsorption time of the O 2 molecule is shorter. Understanding the adsorption behavior of molecules on crystal planes is of great significance to the selection of gas-sensitive materials and the optimization of gas-sensitive properties. • The adsorption speed of O 2 determines the detection time of ethanol molecules. • The adsorption speed of O 2 depends on whether there is competitive adsorption. • Molecules occupy the same active site resulting in competitive adsorption. • O 2 and N 2 occupy the same active site on the SnO 2 110 plane, but not on the 221 plane. [ABSTRACT FROM AUTHOR]

A novel underwater oil storage method with flexible oil bladder is developed in this study. The polymer flexible bladder is used to replace the rigid storage tanks, and is restrained by a shed with anchor cables underwater. To avoid environmental pollution due to the oil permeation is essential to the practical use of the proposed underwater oil storage method. In this study, the mechanism of the permeability of the polymer flexible bladder is investigated by indoor experiment and numerical analysis. The factors including oil types, test environments and pressure differences are considered. The results reveal that the olefins and aromatics are the major controlling components. The pressure gradient in the permeation path is mainly provided by the remaining buoyancy of the oil bladder, which is linearly related to the permeation rate. When the pressure gradient is opposite to the permeation direction, the oil still diffuses with the concentration gradient. An empirical formula for calculating the oil permeation rate is presented to conveniently and directly evaluate whether the oil bladder meets environmental protection and oil loss standards. This study provides a theoretical basis for the application of the present method, and has important significance for the development of underwater oil storage. • A new oil storage method with a flexible oil bladder is proposed. • A series of factors are considered to study the mechanism of oil permeation across polymer membranes. • An empirical formula for calculating oil permeation is presented to evaluate its environmental performance and oil loss. [ABSTRACT FROM AUTHOR]

• In-situ position of ILs into cages of ZIF-8 was proposed to tune cage size. • CO 2 -philic cages constructed by ILs improve CO 2 adsorption. • Molecular simulation reveals increased CO 2 adsorption by increasing ILs in cages. • CO 2 /N 2 selectivity of MMMs is increased due to pore screening and CO 2 adsorption. The regulation on cage size and CO 2 -philic environment of metal–organic frameworks (MOFs) is essential to improve CO 2 capture. In this work, [Bmim][Tf 2 N] was proposed to position into cages of ZIF-8 to achieve the selective permeation of CO 2 by pore screening and CO 2 adsorption. [Bmim][Tf 2 N] was introduced into cages of ZIF-8 by "adsorption-infiltration" strategy. Due to the strong interaction between [Tf 2 N]− and ZIF-8, the cages present a CO 2 -philic environment, which preferentially attracts CO 2 to enter these cages, ensuring the dissolution selectivity of CO 2. Besides, the proper cage size tuned by [Bmim][Tf 2 N] provides CO 2 with a faster transport channel due to its smaller average kinetic diameter than N 2 , guaranteeing the diffusion selectivity of CO 2. Consequently, the CO 2 separation in [Bmim][Tf 2 N]@ZIF-8/Pebax MMMs is intensified. With increasing the [Bmim][Tf 2 N] content in cages of ZIF-8, the pore volume by BET results decreases and the CO 2 adsorption from molecular simulation increases. In response, the CO 2 /N 2 selectivity of [Bmim][Tf 2 N]@ZIF-8/Pebax MMMs is enhanced constantly. Meanwhile, the CO 2 permeability is declined due to the narrowed cage size. All of these results demonstrate the significance of pore screening and CO 2 adsorption induced by [Bmim][Tf 2 N]. Specifically, [Bmim][Tf 2 N] 8 @ZIF-8/Pebax MMM at filler loading of 15 wt% exhibits the CO 2 permeability of 108.3 Barrer and the CO 2 /N 2 selectivity of 86.7, exceeding the 2008 Robeson upper bound. Especially the CO 2 /N 2 selectivity locates at a higher level than those of most reported works, indicating that appropriate tuning of the physicochemical properties within the nanocages of MOFs is significative to improve CO 2 capture. [ABSTRACT FROM AUTHOR]

• We proposed a novel Robust Matrix Completion method based on Rank-One matrix approximation (RMCRO), which divides the noisy and incomplete data matrix into two parts: a low-rank matrix and a sparse matrix, and it is robust to sparse noise. • We use a rank-one matrix pursuit method to approximate the low-rank part of the incomplete data matrix. Therefore, the proposed algorithm can recover the missing entries of the incomplete data matrix and estimate the rank simultaneously. • Extensive experimental results on both synthetic datasets and real world datasets demonstrate the effectiveness of the proposed method for matrix completion and rank estimation. Matrix completion aims at estimating the missing entries of a low-rank and incomplete data matrix. It frequently arises in many applications such as computer vision, pattern recognition, recommendation system, and data mining. Most of the existing methods face two problems. Firstly, the data matrix in real world is often disturbed by noise. Noise may change the date structure of the incomplete matrix, thereby degrade the performance of matrix completion algorithms. Secondly, some existing methods need to preset a reasonable rank as input, and the value of rank will affect the performance of the algorithms. Therefore, we proposed a robust rank-one matrix completion method with rank estimation in this paper. To mitigate the influence of noise, we divide the incomplete and noisy data matrix into two parts iteratively: low-rank and sparse parts. Besides, we use a weighted rank-one matrix pursuit algorithm to approximate the low-rank part of the data matrix, and the rank of the matrix can be estimated with the adaptive weight vector. The performance of the proposed method is demonstrated by experiments on both synthetic datasets and image datasets. The experimental results demonstrate the performance of the proposed method with incompleted matrices distrubed by sparse noise. [ABSTRACT FROM AUTHOR]

[Display omitted] Rhododendron simsii Planch, a folk medicine recorded in the 'Dictionary of Chinese Materia Medica', has been used by many ethnic regions of China to treat various inflammatory and immune-related diseases such as skin disorders and rheumatoid arthritis. However, its protective effect against autoimmune hepatitis and the underlying mechanisms remain unclear. The present study aimed to aimed to investigate the protective effects on autoimmune hepatitis through an integrated approach established by combining chemical composition identification, network pharmacology and in vivo experimental validation. Animal experiments showed that R. simsii Planch extract ameliorated ConA-induced liver injury, as evidenced by a reduction in ALT and AST levels and varying degrees of improvement in liver histopathology, with the R - EE (R. simsii Planch EtOAc extract) treated group showing the most obvious therapeutic effect. Then, chemical investigations into R-EE yielded 15 flavonoid and phenolic acid derivatives namely quercetin 3-O- α -L-rhamnoside (1), tamarixetin 3-rhamnoside (2), isoquercitrin (3), hyperoside (4), myricetin-3-O- α -L-rhamnopyranoside (5), afzelin (6), quercetin-3-O- α -L-arabinofuranoside (7), quercetin-3-O- α -D-arabinopyranoside (8), (+)-catechin (9), kaempferol (10), dihydromyricetin (11), quercetin (12), vanillic acid (13), gallic acid (14) and farrerol (15). Further network pharmacological analysis indicated that the potential mechanism against ConA-induced liver injury is probably related to the regulation of the NF-κB signaling pathway. Experiments confirmed that R- EE could reduce liver damage and downregulate CD4+ and inflammatory cytokine levels and the expressions of NLPR3, COX-2 and p-IκBα, and exhibited considerable hepatoprotective effects in ConA-induced AIH mice, which may be related to its flavonoids, and the underlying mechanism may involve the regulation of the NF-κB signaling pathway. The present results indicated that R. simsii Planch extract has more therapeutic potential in the treatment of autoimmune hepatitis, and provide the experimental basis for traditional application of R simsii Planch in the treatment of inflammatory diseases, and is a potential treatment agent for AIH that deserves further study. [ABSTRACT FROM AUTHOR]

A novel electrochemical sensor basing on an indium tin oxide (ITO) glass electrode modified by hydroxyapatite (HAp) film was fabricated by electrodeposited method for simultaneous detection of Pb 2+ , Cu 2+ and Hg 2+ using differential pulse voltammetry (DPV). Various experimental parameters such as supporting electrolyte and pH were optimized. Under the optimal conditions, the electrode needs no accumulate time. The electrode showed linear correlation in the ranges of 1 × 10 −7 to 1 × 10 −6  M and 3 × 10 −6 to 1 × 10 −5  M for Pb 2+ , 1 × 10 −7 to 1 × 10 −6  M and 1 × 10 −6 to 1 × 10 −5  M for Cu 2+ , and 1 × 10 −7 to 1 × 10 −5  M for Hg 2+ . The limits of detection (S/N = 3) were 1 × 10 −12 , 1 × 10 −12 , 8 × 10 −8  M for Pd 2+ , Cu 2+ and Hg 2+ , respectively. Meanwhile, the developed electrode showed excellent anti-interference capabilities and selectivity with other heavy metal ions and common ions. The electrode has been successfully applied to the detection of above heavy metal ions in tap water. Above all, two major detection mechanisms of developed electrode were also researched in this work. The mechanism of filling Ca deficiency due to that the radiuses of Pb 2+ and Cu 2+ are similar to Ca 2+ , so Pb 2+ and Cu 2+ can fill in the deficiency. That is why the detection limits of Pb 2+ and Cu 2+ are much lower than Hg 2+ . When Ca deficiency has been almost filled, the detection of Pb 2+ and Cu 2+ based on the mechanism of surface adsorption. Because the radius of Hg 2+ is not similar to Ca 2+ , Hg 2+ cannot fill in the deficiency. The detection of Hg 2+ mainly based on the mechanism of surface adsorption. The OH − on the surface of HAp plays a major role in the adsorption of heavy metal ions. [ABSTRACT FROM AUTHOR]

At present, some regions are facing the challenge of environmental degradation, especially in the Pearl River Delta urban agglomeration (PRDUA) which is the most economically-dynamic regions in China. The PRDUA has the characteristics of high comprehensive development level and regional development inequalities, further enlarging the complexities and difficulties in assessing the ecological security. Therefore, we established an ecological footprint (EF) model of urban agglomerations and an extended nonlinear STIRPAT model to explore the spatiotemporal evolution patterns and driving mechanisms of the ecological footprint in the PRDUA, subsequently predicted the impact of population changes on the ecological footprint from 2000 to 2100 using Shared Socioeconomic Pathways scenarios (SSP1-SSP5) database. The findings reveal that the ecological footprint increased significantly, but the average annual growth slowed down after 2014. Simultaneously, the ecological footprint had a phenomenon of spatial aggregation, and gradually migrated to Shenzhen. Growing population contributed most to the expansion of the ecological footprint, followed by per capita GDP and urban green area, while there was uncertainty about the impact of technology on the ecological footprint. Further, our study also demonstrated that the classical Environmental Kuznets Curve (EKC) hypothesis did not exist between economic development and ecological footprint in the PRDUA. Finally, the results of the prediction show that ecological footprint contributed by population changes in most cities of the PRDUA peak in 2040–2060, of which the largest peaks in SSP5 scenario. The findings are intended to provide references for other urban agglomeration in the world, which are with the problem of unbalanced development between economy and ecology. • EF of the PRDUA increased significantly, but the growth slowed down after 2014. • EF has a phenomenon of spatial aggregation, and gradually migrated to Shenzhen. • Growing population makes the largest contribution to EF, while there is uncertainty about the impact of technology to EF. • EF contributed by population changes in most cities of the PRDUA peak in 2040-2060. [ABSTRACT FROM AUTHOR]

Magnetic photocatalytic Fe 3 O 4 @TiO 2 composites have been fabricated by changing the concentration of (NH 2 ) 2 CO. Samples were named as low (NH 2 ) 2 CO concentration group which the (NH 2 ) 2 CO concentration in the synthesis process was below 2.25 mol/L and high (NH 2 ) 2 CO concentration group which the (NH 2 ) 2 CO concentration was above 2.5 mol/L. Photocatalytic degradation experiments of methyl orange showed that the final degradation rates of low (NH 2 ) 2 CO concentration group samples were higher than that of high (NH 2 ) 2 CO concentration group, even better than P25 at the same test conditions. And it was interesting that samples of low (NH 2 ) 2 CO concentration group had smaller values of BET surface areas than that of high (NH 2 ) 2 CO concentration group. It indicated that the improvement of photocatalytic activity which was effected by BET surface areas was not obvious. There were two main factors enhancing the photocatalytic property of low (NH 2 ) 2 CO concentration group: First, diffusing reflection spectra showed that the low (NH 2 ) 2 CO concentration group samples had lower reflectivity, this suggested that the structure improved the efficiency of light absorption; Second, NH 4 + would take up the active sites on the surface of the TiO 2 particles, the FT-IR test results showed that the samples of the low (NH 2 ) 2 CO concentration group samples bonded less NH 4 + , thus leading to the higher photocatalytic activity. It had enlightenment role for optimizing the performance of photocatalytic materials. [ABSTRACT FROM AUTHOR]