bluuebunny/crossref_metadata_2025_split huggingface dataset:
CO2 Adsorption Based on Porphyrin Based Porous Organic Polymers
Authors: An Changwei , Zhang Jun , Guan Xianqi 
Published: April 2023

Abstract
In order to efficiently catalyze the cycloaddition reaction of CO2 and epoxy alkanes under mild environment and no catalyst, this paper designed and synthesized two kinds of porphyrin based porous organic polymers—porphyrin based porous organic polymer containing carboxyl group (ppop-cooh) and porphyrin based porous organic polymer containing quaternary ammonium salt ion pair. Quaternary ammonium salt cation anion pair nucleophilic groups and metal active centers were introduced into the polymer by pre- and post-modification respectively. The chemical structure and pore structure of the polymer were characterized by infrared spectroscopy and physical adsorption instrument, and its effect as a catalyst on the cycloaddition reaction of CO2 and epoxy alkanes was studied. From the results, it is demonstrated that the two polymers had a multistage pore structure with a specific surface area of 302 m2/g-514 m2/g. The synergistic effect of Lewis acid metal ions, nucleophiles and multistage pore structure in the polymer significantly promotes the cycloaddition reaction between CO2 and epoxy alkanes. Under mild conditions (80°C, 0.3 MPa, 24h), the selectivity and conversion of the reaction reach more than 99%. The polymer is repeated for many times. After use, it still has good catalytic performance.
Spatial-Temporal Variation and Trend Prediction of Jinghe Runoff Based on R/S and Mann-Kendall Methods
Authors: Xu Shifeng , Zhao Lixia , Gao Yajun , Jin Shuangyan , Zhang Lijuan 
Published: April 2023

Abstract
This paper used the R/S method and the Mann-Kendall method to analyze and study the Spatial-Temporal variation characteristics, future trends and runoff cycles of the Jinghe River Basin by using the runoff series data from different hydrological stations from 1956 to 2018. The results showed that the Jinghe River basin hydrological stations of Yuluoping, Yangjiaping, Jingcun and Zhangjiashan appeared abrupt changes in 2000, 1985, 1987 and 1995. The annual runoff at each station shows a clear trend of decreasing in the abrupt change year to 2018. The runoff cycle of different stations in the Jinghe River Basin is 9a-10a. The Jinghe River basin will continue its trend of decreasing runoff for some time to come as climate change and human activities influence it.
Wet Oxidation of Excess Activated Sludge from Coal Chemical Industry
Authors: Qin Shulin , Wang Zhongquan , Zheng Weicheng , Zeng Xu 
Published: April 2023

Abstract
Excess activated sludge produced from coal chemical industries has gained much attention, because of the huge volume and high hazardous risk of the sludge. The wet oxidation of coal chemical sludge was studied in this study by using a stainless steel batch reactor. The effects of reaction parameters, including the moisture content, the additional dose of sludge, reaction temperature and the additional amount of oxygen, were discussed. The results showed that the highest removal ratios of COD and TS could reach up to 72.3% and 56.4% respectively with moisture content of sludge 93%, initial oxygen pressure 1.7 MPa under 240°C for 60 min. The mass transfer processes of sludge and oxygen, and the reaction temperature, are very important parameters for the treatment. It was suggested that wet oxidation technology provides a suitable alternative method for the treatment of excess sludge from coal chemical industries.
Improvement of the Sludge Decomposition and Nutrients Release by a Treatment with Potassium Permanganate Combined with an Ultrasonic Process
Authors: Chen Jiandong , Li Haijie , He Ganfeng , Gai Yongwei 
Published: April 2023

Abstract
Ultrasonic decomposition of sludge is a popular method for sludge treatment. Potassium permanganate (KMnO4) was added to promote the reduction of sludge and hydrolysis efficiency. The effect of ultrasonic treatment (ULT) combined with potassium permanganate (KMnO4) preprocessing on the disintegration of waste activated sludge (WS) was studied in this survey. The results indicated that the combined pretreatment of KMnO4 and ULT (150 W, 20 min) significantly improved the decomposition efficiency and nutrient release efficiency of sludge. The volatile suspended solids (VSS) were lessened by 15.22%, which was 56.8% larger than that of raw sludge. The soluble proteins, soluble chemical oxygen demand (SCOD), polysaccharides, and volatile fatty acids (VFAs) were improved by 2005.1%, 464%, 669.8%, and 719.9% respectively. The deliquescent organic matter in sludge products also effectively decreased, demonstrating the effective promoting effect of KMnO4 + ULT. Mechanistic studies showed that ULT united with KMnO4 pretreatment could improve the biodegradability of soluble organic matter by generating reactive radicals, effectively disrupt the structure of cell walls, lyse extracellular polymers, and accelerate the liberation of organic matter. The composite sludge decomposition process further mitigates the harm of sludge to the environment and provides a cleaner and more efficient sludge reduction and utilization method.
Numerical Wind Tunnel Simulation for Pollutants Dispersion with Urban 2003
Authors: Liu Wusheng , Lv Sibo 
Published: April 2023

Abstract
A CFD numerical wind tunnel software was made to simulate the air flow and diffusion of pollutants in urban areas. This softeware is very compact. With the collaboration of the modelling tool AutoCAD and the post-processing software Paraview, a set of standardized numerical simulation process of atmospheric diffusion has been established. The model of the software is based on Open Foam open-source platform, which can perform 3D large-scale parallel operation, and solve 3D Navier Stokes equations on Computer cluster. Based on the observation data of iop9 from the 2003 urban joint field study in Oklahoma City, Oklahoma, the numerical wind tunnel is further evaluated. The wind and concentration field in the near and middle regions, as well as the wind speed, wind direction, friction velocity and turbulent kinetic energy (TKE) profiles in the urban wake region are compared between the numerical wind tunnel and the urban 2003 field experiment. The results show that the numerical wind tunnel can be an economic and effective tool to simulate the diffusion of pollutants in urban areas.
Role of Organic Matter in Reducing Nitrogen-Leaching Loss and Improving Yield of Stem Mustard and Corn in the Three Gorges Reservoirs
Authors: Chen Jieru , Tang Zhenya , Chu Jun , Wang Kaisui , Shi Xiaojun 
Published: April 2023

Abstract
The effects of organic and/or chemical nitrogen (N) fertilizer application on nitrogen leaching and mustard yield in the Three Gorges Reservoir area is still unknown. Four years’ fertilizer experiments, including organic matter and chemical fertilizer incorporation (MC), chemical fertilizer (CF), organic fertilizer (M), and non-fertilizer (Control) were used to understand role of organic matter and fertilizer incorporation in reducing nitrogen-leaching loss and improving yield of stem mustard and corn in three gorges reservoirs. Results showed that MC led to the highest yield, sustainable yield index, percent fertilizer recovery, and nitrogen agronomy efficiency and N uptake of stem mustard and corn. Leaching loss of N was significantly positively correlated with cumulative precipitation. CF treatments led to obviously higher N loss with the cumulative precipitation more than 44.3 mm. the N loss in MC treatment exceeded that in M treatment or control with cumulative precipitation more than 96.2 mm. Total amounts and concentration of N in leaching water followed the trends: CF> M > MC > Control. Organic fertilizer could reduce nitrogen-leaching loss and improve yield of stem mustard and corn with incorporation of fertilizer.
Evaluation of Fertilizer Inputs and Soil Nutrient Status in Apple Orchards in China
Authors: Men Xiaopeng , Fan Zongzhen , Wang Yanfang , Wang Yubin , Wang Yi , Han Zhenhai 
Published: April 2023

Abstract
Apple is an important horticultural crop in China and its production consumes large amounts of Chemical fertilizers. In a survey of more than 300 Chinese apple growers, we found that small farmers’ fertilizer inputs are blind. Current research lacks a comprehensive evaluation of fertilizer inputs and soil nutrient status for apple production in China, but the evaluation work will play a supporting role in the macro management decision of nutrient resources. In this study, a database of fertilizer inputs and soil nutrients in five major apple producing areas in China was constructed by means of data integration. Two main conclusions can be drawn from the analysis of the database. Firstly, the chemical N and P fertilizer inputs exceed the recommended use in all five production areas, and secondly, the organic matter content of orchard soils in the five production areas only reaches a maximum of level 3. The research shows that China’s agricultural authorities should carry out macro management of nutrient resources in apple orchards, so as to guide different producing areas to adjust fertilizer input according to their soil environment, so as to improve the utilization rate of fertilizer.
Study on Rice Phenological Differences under Heavy Metal Stress by Using Multi-source Remote Sensing Time-Series Images
Authors: Liu Tianjiao , Chen Jiankui 
Published: April 2023

Abstract
Heavy metal pollution is surveyed rapidly and accurately, which is of great significance for soil pollution control. heavy metal pollution on farmland results in phenological changes, and we can use remote sensing technology to observe these changes. In the paper, Normalized Difference Vegetation Index (NDVI) time-series is built based on multi-source remote sensing images. Savitzky-Golay filter (S-G filter) was applied for denoising and reconstructing the time series. NDVI time series were used to calculate phenological indicators. Five phenological indicators were selected, which include seasonal amplitude, growth rate, seasonal length, seasonal integral and base level, to study on effect of heavy metal stress on rice phenology. The results showed that differences in phenological indexes at different levels of heavy metal stress as well as the phenological indicators under the stressed condition were generally lower than those under mild and moderate stress. From the findings, it can be concluded that the superiority of remote sensing phenological information in the monitoring of heavy metal stress in rice, and a new method for distinguishing heavy metal stress in rice will be provided.
Load Forecasting Research of Markov Chain based on Data Modeling
Authors: Feng Haoxuan 
Published: April 2023

Abstract
The introduction of the electricity market plays an irreplaceable role in assisting the power industry to achieve stable operation and planning of the power grid, promoting the effective use and dispatch of electric energy, and avoiding the waste of resources. The role of load forecasting for the electricity market is self-evident, in the context of big data, by building a load forecasting model based on the Markov chain, and using the actual data of a certain region for simulation calculation. The results show that the Markov forecasting method can play a good role in medium and long-term power load forecasting, and can be used as a supplement to conventional load forecasting.
Research on Measuring Method of Drilling Parameters Based on Parameter Measuring Device
Authors: Fu Qiang , Mao Yachun , Kang Quanyu , He Liming , Bai Yu 
Published: April 2023

Abstract
Mainly aiming at the research on the method of measuring the multi-source parameters of blasting boreholes in open pits, using the multi-source parameters of the measuring device to calculate the minimum resistance line distance. Through the intelligent analysis of the minimum resistance line distance, the blasting effect is improved, and the secondary blasting caused by the increase of the block rate can avoid the phenomenon of sudden increase in blasting cost and waste of resources caused by the increase of the mass rate. It ensures the safe production of the mine and the safety of the lives and property of the surrounding people.
Thermoluminescence of Natural Quartz Grains Beside Huguangyan Maar Lake
Authors: Guo Jingyuan , Gao Mu , Xiong Zhengye , Wang Xiaochun , Liu Hao 
Published: April 2023

Abstract
In order to study the relationship between the thermoluminescence (TL) properties of natural quartz crystals and the irradiation history, the TL test of quartz particles was carried out on volcanic ash near Huguangyan Maar Lake in Zhanjiang City. The TL glow curve and dose response of quartz were measured. The parameters of TL traps are calculated, and the activation energies corresponding to the TL peaks of 260, 310 and 365 °C of quartz grains are 1.34, 1.44 and 1.51eV, respectively. The peak position of the TL glow curve changes mildly with the increase of irradiation dose of quartz particles, indicating that the energy of a TL trap is not a single value, but an energy distribution; in the range of 355 °C to 375°C, the TL sensitivity changes greatly with the increase of the historical irradiation dose.
Bayesian Method for Inverse Scattering Problem of Interior Cavity with Phaseless Data
Authors: Guo Wenke , Wang Yujie , Zheng Enxi 
Published: April 2023

Abstract
This paper is concerned with the inverse acoustic scattering problem of a sound soft cavity based on phaseless near-field data. By combining the reference circle technique with the Bayesian method, this paper presents a numerical algorithm to retrieve the shape of the interior cavity from phaseless data. In this paper, the well-posedness of the Bayesian method is discussed. The posterior distribution of the shape parameters is obtained by DRAM algorithm and the reconstruction of the cavity boundary is acquired by taking the average value of the posterior distribution.
A Heuristic Method for Solving Ship Floating Problems Based on Improved Particle Swarm Optimization
Authors: Shao Houhua , Xu Lijun , Liu Chunlei , Yin Yong 
Published: April 2023

Abstract
The study of ship floating balance plays a very important role in the safety of ships. According to certain conditions of ship statics, the nonlinear equations of ship balance can be established with relevant parameters such as ship weight, draft, heeling angle, longitudinal inclination angle and static moment. In this paper, motivated by the least square method, the nonlinear equations of floating equilibrium are transformed to a nonlinear programming problem. The draught, heel and trim of the ship are taken as variables, and inequality constrained by the actual situation. The penalty function for nonlinear programming is considered and minimized by particle swarm optimization. The proposed optimization method simplifies the calculation process by avoiding the calculation of parameters. Numerical results verify the efficiency of the proposed method.
Comparative Study of Bistable Vibration Energy Harvester Using Different Elastic Boundary
Authors: Li Xuefeng , Zhang Jingyu , Yang Kai , Li Renfu 
Published: April 2023

Abstract
This paper demonstrates a novel bistable energy harvester coupled with a nonlinear elastic boundary (NEB-BVEH). The nonlinear elastic boundary changes the dynamic response of the bistable vibration energy harvester and improves its performance by providing additional support for the inclined spring through coupled dynamics. This work considers the performance of bistable vibration energy harvesters using different elastic boundary under different excitation amplitudes, including bistable energy harvester with linear elastic boundary (LEB-BVEH) and NEB-BVEH with different horizontal spring stiffness. The comparative results show that the performance of NEB-BVEH and LEB-BVEH is approximately the same under small excitation amplitude. However, NEB-BVEH with adding horizontal springs can significantly improve performance compared to LEB-BVEH under larger excitation amplitude. Results of the investigated case show that the bandwidth of NEB-BVEH is increased by 89.31%. The output power is increased by more than 25%. A comparative study demonstrates the superiority of NEB-BVEH, which is very beneficial for energy harvesting.
Some Conclusions of an Optimal Subdivision Problem
Authors: Zhu Yuyang 
Published: April 2023

Abstract
Let Habe a-gon with unit edges. DivideHa
into b parts:H

a(1), H

a(2), …, H

a(b) and let the division as Δ(a, b). Let dH

a(k) be the diameter of H

a(k),D(a,b)=max{dH

a(k)}1≤k≤b
, ρ(a, b)=infΔ(a, b){D(a,b)}. We use geometric extremum theory to estimate the range of ρ(a, b), and give the result that ρ(a, b)≥[a(b π)−1 cot(π a
−1)]1/2. For any ε >0, there is a b∈N
+, such that ρ(a, b)< [(2 π (27)−1/2+ ε)a(b π)−1cot(π a
−1)]1/2. We also prove that [6(31/2
π
−1)]1/2≤lim
b→∞
b
1/2
ρ(a, b)≤2.
Nonlinear Response of 1D Large-U Charged Bose Hubbard Model in Electric Field
Authors: Zheng Yong 
Published: April 2023

Abstract
The nonlinear response behavior of 1D large-U charged Bose Hubbard model with a reduced Hamiltonian in electric field has been studied. By transforming the Hamiltonian into a tensor-state space introduced via auxiliary spinless-fermions and the sequence of empty- and doubly-occupied states along the lattice, we have discussed the time-evolution behavior of the system, and found that the charge current always shows Bloch oscillations. It is also found that higher-harmonic components, though small in magnitude, can appear in the corrected charge current.
Research and Practice on the Mining Vehicle Loading Evaluation by Single-Line LIDAR Top View Scanning
Authors: Sun Jian , Chai Qingping , Sun Houguang , Peng Yuanhang 
Published: April 2023

Abstract
There are many challenges associated with the manual accounting of mining vehicle loading when installation of weighbridge is impeded by environmental constraints. This article proposes the method that employs the single-line LIDAR, which was fixed at a height, to obtain the top point cloud data of the passing mining vehicles by overhead scanning, and to configurate three-dimensional point cloud models of the materials for rapid accounting of loading. The single-line LIDAR meanwhile develops the management system of the cloud data to analyze and manage the related results, aiming to fulfil the various needs of data backup and query. Tests of proposed method were conducted via evaluating the loading of both unloaded and fully loaded mining vehicles, the test results show that the average absolute error of the loading evaluation is 1.71% and the average consistency error is 0.28%, both of which meet the accuracy requirements of production, and therefore verify the feasibility of the proposed method.
Inspection Route Optimization of Unmanned Aerial Vehicle in the Presence of Electrical Field around the Overhead Line
Authors: Huang Tao , Rao Donglong , Su Junlong , Zhou Miaolin , Wang Hang 
Published: April 2023

Abstract
Planning of unmanned aerial vehicle (UAV) route is vital for quality of the image acquisition and the safety of UAVs in the inspection of overhead lines (OHLs). However, the influence of the electrical field generated by OHLs on the UAV inspection route was not taken into consideration in previous efforts. In this paper, an optimal route planning method is proposed to avoid UAVs flying too close to OHLs. The results in simulation shows that the UAV keep safe distance with the OHLs.
An Ultra-thin, Switchable Ultra-narrow Band Absorber for High-performance Terahertz Sensing
Authors: Yu Zhisheng , Peng Zhen , Zheng Zhesong , Lan Huiting , Feng Shiping , Wang Shixing , Zhang Min , Li Ling , Liang Huawei , Su Hong 
Published: April 2023

Abstract
In this paper, an ultrathin terahertz metamaterial absorber consisting of Au pattern, polyimide and Au film is proposed. Based on the finite element method, the simulation consequences indicate that when its thickness is 9.4 m, there is a narrow absorption peak for the TE wave at 7.73 THz with near-perfect absorption of 99.8% and a full width at half maximum of 0.0896 THz, resulting from impedance matching and plasma resonance. And the absorption switching from a dual-band to a multi-band or a single-band to a dual-band absorption can be achieved for TM and TE waves by changing the incident angle or polarization angle. Furthermore, the absorption can also be switched from 99% to 0% by changing the polarization angles, and has a high tolerance of polarization angle down to more than 20 degrees. In addition, its application in the sensor is also studied at 7.73 THz, where its refractive index sensitivity and thickness sensitivity can achieve 1.2 THz/RIU and 0.065 THz/m, respectively. This might be utilized for monospectral imaging, biological diagnosis, and environmental monitoring.
Error Estimates of High-order Conservative Schemes for the Generalized Nonlinear Schrödinger Equation in One Dimension
Authors: Wang Xi , Hua Dongying , Li Shucun , Li Xianggui 
Published: April 2023

Abstract
In this paper, we use the high-order difference operator Dμ to compensate the central difference operator

δ

x

2

. Then, we discretize time by the time-midpoint method. Fully discrete schemes are obtained for the generalized nonlinear Schrödinger equation. For the high-order methods, conservation of mass and energy can be proved theoretically in the discrete sense. Then, to establish the optimal error estimates without any requirement on the grid ratio, we adopt the cut-off function technique. The error estimates of the schemes are proved to be of O(τ2 + h2(μ+1)) with time step size τ and mesh size h. Some numerical experiments are given to verify the accuracy order. In addition, the dynamics of the generalized nonlinear Schrödinger equation in one dimension are simulated.
Hollow/sponge-core β-carotene-poly-vinylpyrrolidone (PVP) Electrospun Fibers using High-pressure CO2 Electrospinning
Authors: Zhu Li , Wang Tao , Wahyudiono  , Goto Motonobu , Kanda Hideki 
Published: April 2023

Abstract
Polyvinylpyrrolidone (PVP) is used in various applications because of its unique chemical and physical properties, including biocompatibility and low toxicity. In this study, we successfully prepared ethanol solution-based hollow-core β-carotenoid PVP fibers using high-pressure carbon dioxide (CO2) at 5 MPa and 318 K ambient temperature, a polymer solution at 333 K, an 8-cm tip-to-collector distance, and DC voltage of 15 kV. In this study, the morphological and physical properties of the electrospun products were investigated by using scanning electron microscopy (SEM), Fourier transform infrared (FT-IR) scanning spectroscopy, X-ray diffraction (XRD), and differential scanning calorimetry (DSC).