•Biochar reduced runoff volumes and ratios of slopping land.•Biochar decreased the concentrations of N and P in the runoff.•Biochar has induced significant reduction of the nutrients losses.•Biochar ...exhibits a risk of increasing sediment loss under tillage conditions.
The effects of biochar on runoff and loss of soil and nutrients in the subtropical regions of China are rarely documented. Two field experiments, an orchard and a cropland field were set up, involving two treatments: biochar (BC) and no-biochar (NBC). The effects of BC on runoff volumes and ratios, sediment yield and the level of nutrient losses were monitored and evaluated over three years (2014–2016). Results showed that the treatment of BC induced a significant reduction in the runoff and nutrients losses. By plotting the data collected for the BC application, we observed that the average annual runoff decreased by 19–28%, whereas the average annual sediment yield by 11%. The cumulative values of total nitrogen (N) and phosphorus (P) losses were also substantially minimized by the BC treatment compared with the NBC one (P<0.05). However, the average annual concentrations of total N and P losses as obtained from the BC plots (16.21mgL−1 and 0.72–0.99mgL−1) were still high, and exceeding the wastewater discharge standard (N: 15mgL−1 and P: 0.5mgL−1). In addition, under tillage conditions, the BC application led to larger sediments yield (6.5gm−2) in contrast with the NBC treatment (5.5gm−2). In general, these findings can suggest that BC exhibits a vital efficiency in the control of soil erosion process, but there is a risk of increasing sediment loss under tillage conditions, which might need to be made up by combined with biological and agronomic managements such as straw mulching or adding polyacrylamide into soil in order to control further soil erosion.
In this work, bilinear residual network method is proposed to solve nonlinear evolution equations. The activation function in final layer of deep neural network cannot interact with the neuron inside ...the deep neural network, but the residual network can transfer the input layer to the activation function in final layer to realize the interaction within the network. This reduces the complexity of the model and gives more interactive results. The steps of solving the exact analytical solution through the residual network are given. The rogue wave solution of Caudrey–Dodd–Gibbon–Kotera–Sawada-like equation is obtained by using the bilinear residual network method. Characteristic plots and dynamic analysis of these rogue waves are given.
A new method named bilinear neural network is introduced in this paper, and the corresponding tensor formula is proposed to obtain the exact analytical solutions of nonlinear partial differential ...equations (PDEs). This is the first time that the neural network model is used to find the exact analytical solution, and this method covers almost all methods of constructing a function after bilinearization to solve nonlinear PDEs. Furthermore, this method is most likely a universal method to obtain the exact analytical solutions of nonlinear PDEs. Abundant arbitrary functions solutions of the reduced p-gBKP equation are obtained by using this method. Various beautiful plots of the presented solutions, which show diversity of exact solutions to PDEs, are made. By choosing appropriate values and functions, the fractal solitons waves are obtained and the self-similar characteristics of these waves are observed by reducing the observation range and magnifying local images. Via various three-dimensional plots, the evolution characteristics of these waves are exhibited.
It is well known that most classical test functions to solve nonlinear partial differential equations can be constructed via single hidden layer neural network model by using Bilinear Neural Network ...Method (BNNM). In this paper, the neural network model of test function for the (3+1)-dimensional Jimbo–Miwa equation is extended to the “4-2-3” model. By giving some specific activation functions, new test function is constructed to obtain analytical solutions of the (3+1)-dimensional Jimbo–Miwa equation. Rogue wave solutions and the bright and dark solitons are obtained by giving some specific parameters. Via curve plots, three-dimensional plots, contour plots and density plots, dynamical characteristics of these waves are exhibited.
Hypochlorous acid (HOCl), a well-known universal disinfectant in clinical practice, plays important roles in immune systems of animal and human bodies. For understanding the roles of HOCl in living ...systems, a number of approaches, including chemiluminescence, colorimetric, electrochemical and chromatographic methods have been explored. For the detection of HOCl in live organisms, cutting-edge techniques, such as fluorescence/phosphorescence molecular probes, responsive nanoprobes, Raman and activatable photoacoustic sensors, have also been developed recently. In this review, the recent advances in the development of bioanalytical methods for detection of HOCl in environmental and biological specimens were summarized. More specifically, traditional techniques for assay of HOCl in bulk solution were initially discussed, and then fluorescence molecular probes, phosphorescence probes, responsive nanoprobes and other methods for HOCl detection were reviewed, which gives an overview of the developments and applications in bioanalytical methods for HOCl detection.
•Production and functions of HOCl in biological systems were introduced.•Recent development of bioanalytical methods for HOCl analysis was reviewed.•Performance for the detection of HOCl by fluorescence probes were compared.•Challenges and future outlooks for the development of bioanalytical methods for HOCl were discussed.
•Injectable temperature-sensitive hydrogels for pH-sensitive drug release are prepared.•Cancer cells (Hela) exhibit good adhesion to the hydrogels.•The micro structure and performance of the ...hydrogels can be tuned.
Hydrogels based on chitosan/hyaluronic acid/β-sodium glycerophosphate demonstrate injectability, body temperature sensitivity, pH sensitive drug release and adhesion to cancer cell. The drug (doxorubicin) loaded hydrogel precursor solutions are injectable and turn to hydrogels when the temperature is increased to body temperature. The acidic condition (pH 4.00) can trigger the release of drug and the cancer cell (Hela) can adhere to the surface of the hydrogels, which will be beneficial for tumor site-specific administration of drug. The mechanical strength, the gelation temperature, and the drug release behavior can be tuned by varying hyaluronic acid content. The mechanisms were characterized using dynamic mechanical analysis, Fourier transform infrared spectroscopy, scanning electron microscopy and fluorescence microscopy. The carboxyl group in hyaluronic acid can form the hydrogen bondings with the protonated amine in chitosan, which promotes the increase of mechanical strength of the hydrogels and depresses the initial burst release of drug from the hydrogel.
Abstract
Manipulating valley-dependent Berry phase effects provides remarkable opportunities for both fundamental research and practical applications. Here, by referring to effective model analysis, ...we propose a general scheme for realizing topological magneto-valley phase transitions. More importantly, by using valley-half-semiconducting VSi
2
N
4
as an outstanding example, we investigate sign change of valley-dependent Berry phase effects which drive the change-in-sign valley anomalous transport characteristics via external means such as biaxial strain, electric field, and correlation effects. As a result, this gives rise to quantized versions of valley anomalous transport phenomena. Our findings not only uncover a general framework to control valley degree of freedom, but also motivate further research in the direction of multifunctional quantum devices in valleytronics and spintronics.
Low n‐doping efficiency and inferior stability restrict the thermoelectric performance of n‐type conjugated polymers, making their performance lag far behind of their p‐type counterparts. Reported ...here are two rigid coplanar poly(p‐phenylene vinylene) (PPV) derivatives, LPPV‐1 and LPPV‐2, which show nearly torsion‐free backbones. The fused electron‐deficient rigid structures endow the derivatives with less conformational disorder and low‐lying lowest unoccupied molecular orbital (LUMO) levels, down to −4.49 eV. After doping, two polymers exhibited high n‐doping efficiency and significantly improved air stability. LPPV‐1 exhibited a high conductivity of up to 1.1 S cm−1 and a power factor as high as 1.96 μW m−1 K−2. Importantly, the power factor of the doped LPPV‐1 thick film degraded only 2 % after 7 day exposure to air. This work demonstrates a new strategy for designing conjugated polymers, with planar backbones and low LUMO levels, towards high‐performance and potentially air‐stable n‐type polymer thermoelectrics.
Stability: A new rigid coplanar poly(p‐phenylene vinylene) (PPV) derivative, LPPV‐1, is synthesized with a rigid planar backbone and low‐lying LUMO, which lead to reduced conformational disorder and high n‐type doping efficiency. The conductivity of LPPV‐1 is up to 1.1 S cm−1, and the power factor is only 2 % after a 7 day exposure to air. This work represents an effective strategy towards high‐performance and potentially air‐stable n‐type polymer thermoelectrics.
Endogenous hydrogen sulfide (H2S) exists in multiple physiological processes. In order to further understand the action mechanism of H2S in cells and human body, we proposed a smart surface-enhanced ...Raman scattering (SERS) nanoprobe, Au core-4-mercaptobenzonitrile-Ag shell nanoparticle (Au@4-MBN@Ag), for the detection of endogenous H2S in living cells based on the reaction between Ag shell and sulfide species. 4-MBN was selected as the SERS reporter to avoid interference from cellular molecules. With the sulfide concentration increasing, the Ag2S constantly formed, and consequently the SERS signal intensity of Au@4-MBN@Ag gradually decreased owing to the weaker SERS activity of Ag2S. With the nanoprobes, this method not only offers a high sensitivity for H2S detection at an nM level, but also achieves the goal of non-background analysis. It displays satisfactory anti-interference capability and a good linear relationship with sulfide concentration ranging from 50 nM to 500 μM, and an estimated detection limit is 0.14 nM. The Au@4-MBN@Ag nanoprobes were successfully applied to detect endogenous H2S in living HepG2 cells stimulated by pyridoxal 5-phosphate monohydrate. This work offers a potential analytical method in the related research of H2S physiological function.
Display omitted
•Au core-4-mercaptobenzonitrile-Ag shell nanoprobes offer high sensitivity to detect hydrogen sulfide at nM level.•Endogenous hydrogen sulfide in HepG2 cells was dynamically monitored by SERS.•Non-background detection in living cells is realized by virtue of 4-MBN molecules.