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Maize kernel damage dynamic prediction in threshing through PSO-LSTM and discrete element modelling

BIOSYSTEMS ENGINEERING 2024年 242卷 179-195页

作者： Fang, xuwen Zhang, Jinsong zhao, Xuelin Zhang, Qiang Zhang, Li Zhou, Deyi Yu, Chunsheng Hu, Wei Wang, Hao Jilin Univ Coll Biol & Agr Engn Changchun 130022 Peoples R China

This study presents the development of a maize ear model and a predictive approach for kernel damage in maize threshing, integrating physical simulation and predictive analytics to understand better and forecast threshingrelated damage. First, a maize ear model was developed to analyse kernel damage during threshing. Through the angle of repose experiments, the optimal number of spheres for the kernel model was established as 65. Tensile tests were conducted to evaluate the kernel-cob bond strength, revealing an average relative error in the bonding force of 8.71%. Vogel impact energy modelling was applied to the kernel threshing process to determine kernel damage. The correlation between the speed of seed grain movement and the occurrence of damage was analysed by post-processing to identify locations with frequent kernel damage in the drum. In-depth data analysis of kernel damage in the threshing drum further elucidates the inherent relationship between kernel velocity and damage extent. The study then focused on applying neural networks to predict damage rates. The comparative evaluation shows that the PSO-LSTM model has better prediction accuracy than LSTM and RNN models, with the PSO-LSTM network achieving an RMSE of 0.096, a R2 of 99.96%, and a final damage rate of 2.41% in validation tests. Threshing experiments were conducted to verify the model, showing a 1.4% discrepancy between predicted and actual damage rates. This study proposes a kernel damage prediction model and provides new insights and directions for the structural design of threshing drums.

关键词： Maize threshing Kernel damage prediction Machine learning in agriculture Agricultural automation LSTM network

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Arbidol/IFN-a2b therapy for patients with corona virus disease 2019: a retrospective multicenter cohort study

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MICROBES AND INFECTION 2020年第4-5期22卷 200-205页

作者： Xu, Ping Huang, Jianping Fan, zhao Huang, Wendi Qi, Minghua Lin, xuwen Song, Weidong Yi, Li Peking Univ Shenzhen Hosp Dept Resp & Crit Care Med Shenzhen 518036 Guangdong Peoples R China Hubei Jianli People Hosp Dept Infect Dis Jingzhou 433300 Hubei Peoples R China Peking Univ Dept Emergency Shenzhen Hosp Shenzhen Guangdong Peoples R China Peking Univ Dept Neurol Shenzhen Hosp 1120 Lianhua Rd Futian Area Shenzhen 518036 Guangdong Peoples R China

The spread of COVID-19 is accelerating. At present, there is no specific antiviral drugs for COVID-19 outbreak. This is a multicenter retrospective cohort study of patients with laboratory-confirmed COVID-19 infection pneumonia from 3 hospitals in Hubei and Guangdong province, 141 adults (aged ≥18 years) without ventilation were included. Combined group patients were given Arbidol and IFN-α2b, monotherapy group patients inhaled IFN-α2b for 10-14 days. Of 141 COVID-19 patients, baseline clinical and laboratory characteristics were similar between combined group and monotherapy group, that 30% of the patients leucocytes counts were below the normal range and 36.4% of the patients experienced lymphocytopenia. The duration of viral RNA of respiratory tract in the monotherapy group was not longer than that in the combined therapy group. There was no significant differences between two groups. The absorption of pneumonia in the combined group was faster than that in the monotherapy group. We inferred that Arbidol/IFN - 2 b therapy can be used as an effective method to improve the COVID-19 pneumonia of mild patients, although it helpless with accelerating the virus clearance. These results should be verified in a larger prospective randomized environment.

关键词： COVID-19 2019-nCoV Pneumonia Arbidol IFN-α2b Treatment RNA

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Intelligent generation method of 3D machining process based on process knowledge

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INTERNATIONAL JOURNAL OF COMPUTER INTEGRATED MANUFACTURING 2020年第1期33卷 38-61页

作者： Jing, xuwen Zhu, Yuping Liu, Jinfeng Zhou, Honggen zhao, Peng Liu, Xiaojun Tian, Guizhong Ye, Hua Li, Qun Jiangsu Univ Sci & Technol Sch Mech Engn Zhenjiang Jiangsu Peoples R China Jiangsu Univ Sci & Technol Sch Mat Sci & Engn Zhenjiang Jiangsu Peoples R China Southeast Univ Sch Mech Engn Nanjing Jiangsu Peoples R China Hudong Heavy Machinery Co Ltd Inst Comprehens Technol Shanghai Peoples R China

Intelligent manufacturing has become the trend of global manufacturing industry, and the core of the new industrial revolution and the commanding point of Made in China 2025. Process planning is an important part of intelligent manufacturing. To improve the speed and accuracy of intelligent generation of machining process, a systematic intelligent generation method of machining process based on process knowledge is proposed. Firstly, a method of modelling and management of process knowledge is presented. Secondly, by combining case-based reasoning with rule-based reasoning, accurate process information of machining features is obtained. Then, the skeleton process is formed. Thirdly, through the analysis of the precedence constraints and the processing experience constraints, the precedence relation between machining features is determined. Moreover, the precedence between process operations is formulated by process constraint matrix. Finally, a genetic algorithm (GA) approach is presented to obtain the global optimal process route for the part based on working step with process information. Taking the connecting rod and piston of marine diesel engine and the spindle box shell as the research object, the feasibility of this method is verified.

关键词： Process knowledge skeleton process process constraint matrix genetic algorithm machining process

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Effects of build direction and microstructure on fatigue crack growth behavior of Ti6Al4V fabricated by laser powder bed fusion

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FATIGUE & FRACTURE OF ENGINEERING MATERIALS & STRUCTURES 2024年第7期47卷 2396-2410页

作者： Xie, Peidong Xie, Deqiao Zhou, Kai Gu, xuwen Naqvi, Syed Mesum Raza Shen, Lida Tian, Zongjun zhao, Jianfeng Nanjing Univ Aeronaut & Astronaut Coll Mech & Elect Engn Nanjing Peoples R China Nanjing Univ Aeronaut & Astronaut Coll Astronaut Nanjing 210016 Peoples R China Nanjing Univ Aeronaut & Astronaut Wuxi Res Inst Wuxi Peoples R China Natl Ctr Supervis & Inspect Addit Mfg Prod Qual Wuxi Peoples R China

This study compares the fatigue crack growth (FCG) behavior of Ti6Al4V parts fabricated by laser powder bed melting (LPBF) with four build directions (0 degrees, 30 degrees, 60 degrees, and 90 degrees) and two heat treatments and analyzed the effect of build direction and microstructure on FCG. The results show that the build direction has a significant effect on the FCG rate. Particularly, specimens with 90 degrees build direction have the best FCG resistance while the 0 degrees specimens have the worst. Furthermore, the fragile deposition layer boundary is the main cause of the crack deflection. The microstructure shows that the columnar beta grains have less effect on FCG. The increase in resistance to FCG after heat treatment is attributed to the lath-like alpha grains consuming the energy for FCG. As compared to needle-like alpha ' grains, the lath-like alpha grains are more likely to initiate intergranular fracture and secondary cracking, leading to rugged crack tip paths. The effect of build direction on FCG of LPBF-Ti6Al4V part is significant. The heat-treated lath-like alpha grains have better resistance to FCG. Cracks tend to expand in the direction of parallel deposition layers. Secondary cracking is related to build direction and microstructure.

关键词： build direction fatigue crack growth LPBF microstructure Ti6Al4V

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Determination of common ginsenosides in Kang'ai injection by aqueous two-phase extraction with deep eutectic solvents and HPLC-UV/DAD

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MICROCHEMICAL JOURNAL 2018年 137卷 302-308页

作者： Li, Peng zhao, Pengyun Liu, Weijie Jiang, Yifu Wang, Wenjiao Bao, Longyue Jin, Yongri Li, xuwen Jilin Univ Coll Chem Changchun 130012 Jilin Peoples R China

In this work, four kinds of deep eutectic solvents (DESs), composed of choline chloride (ChCl) and several alcohols, were synthesized and characterized by H-1 NMR and FT-IR spectra. Based on DES ( ChCl and 1,4-butanediol) and inorganic salt solution (dipotassium phosphate, K2HPO4), aqueous two-phase system (ATPS) coupled with high-performance liquid chromatography has been developed and applied. This method was used for the efficient extraction and determination of eight common ginsenosides (including ginsenoside Rg(1), Re, Rf, Rg(2), Rc, Rb-2 and Rd) in the traditional Chinese medicine injection named Kang'ai injection. To achieve optimum extraction performance, the experimental conditions were optimized, including type and amount of DES and salt, ultrasound time, temperature and pH value. In the dynamic linearity range, experimental results showed satisfactory recoveries of analytes ranging from 92.7-110.8% with the relative standard deviations (RSDs) ranging from 1.2-3.9%. It has been proved that DES-ATPS has great potential for determination of active ingredients in traditional Chinese medicine injection as well as samples in other analytical science field. (C) 2017 Elsevier B.V. All rights reserved.

关键词： Aqueous two-phase system Ginsenosides High-performance liquid chromatography Kang'ai injection

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Research on the intelligent generation method of MBD model 3D marking using predefined features

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CONCURRENT ENGINEERING-RESEARCH AND APPLICATIONS 2020年第3期28卷 222-238页

作者： Jing, xuwen Tang, Mingming Liu, Jinfeng Zhou, Honggen zhao, Peng Wang, Zhen Cao, Xuwu Sheng, Sushan Wei, Gang Jiangsu Univ Sci & Technol Sch Mech Engn Zhenjiang 212003 Jiangsu Peoples R China Jiangsu Univ Sci & Technol Jiangsu Prov Key Lab Adv Mfg Marine Mech Equipmen Zhenjiang Jiangsu Peoples R China Shanxi Diesel Engine Heavy Ind Co Ltd Xingping Shanxi Peoples R China

Model-based definition (MBD) carries out a technological innovation for global manufacturing, application of MBD technology plays an important supporting in process design, product manufacturing and other development activities, rapid creation of MBD models have become a key to reduce time and cost for enterprises. However, interactive dimensioning method has severely hampered the efficiency of MBD model creation. This paper mainly studies the dimensions intelligent marking method based on the predefined features to solve the rapid modeling problem of MBD model. Firstly, the expression model of dimensions metadata is established based on the feature identifier. Secondly, by establishing an association mechanism between the dimensions and the predefined feature, the "model-feature-dimensioning" association model is formed. Thirdly, through analysis of the dimensioning type, the intelligent dimensioning algorithm process is determined. Moreover, the completeness check of the dimensions is guaranteed during the marking process. Finally, taking the connecting rod and crankshaft of marine diesel as the research object, the effectiveness of this method is verified.

关键词： MBD dimension predefined features metadata intelligent marking

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Adsorption of Orange G on Activated Porous Carbon Derived from Coal Tar Pitch: Experimental and DFT Study

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LANGMUIR 2024年第48期40卷 25471-25482页

作者： Huang, Linlin Zhang, xuwen Liu, Tingting Wang, Lin Li, Lixin Li, Da Sheng, Tao Dong, Zilong zhao, Xinyue Heilongjiang Univ Sci & Technol Coll Environm & Chem Engn Harbin 150022 Peoples R China Harbin Inst Technol State Key Lab Urban Water Resource & Environm Harbin 150000 Peoples R China Northeast Agr Univ Sch Resources & Environm Harbin 150030 Peoples R China

A coal tar pitch-based porous carbon adsorbent (CPA) was synthesized through a straightforward method involving the heating of a mixture of KOH and coal tar pitch (CTP). This CPA exhibited a high surface area of 1811.2 m2 g-1 and a large pore volume of 0.94 cm3 g-1 when prepared with a CTP to KOH mass ratio of 1:4 at 800 degrees C. Parameters such as the heating temperature and activator dose were optimized to enhance the adsorption efficiency. The prepared CPA was extensively characterized by SEM, XRD, FTIR, and BET measurements. Notably, CPA presented a distinct adsorption performance for Orange G (OG), achieving a maximum adsorption capability of 449.7 mg g-1. Kinetic studies indicated that the adsorption process followed the pseudo-second-order model, while the adsorption isotherm data demonstrated that both chemical and physical interactions favored OG adsorption. Thermodynamic analysis revealed that the adsorption of OG on CPA was spontaneous and exothermic and increased the entropy. Density functional theory (DFT) calculations provided insights into the adsorption mechanism, highlighting electrostatic interactions, hydrogen bonds, and pi-pi interactions as the dominant processes governing OG adsorption onto the adsorbent.

关键词： Potassium hydroxide

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Direct Arylation Polycondensation toward Water/Alcohol-Soluble Conjugated Polymers: Influence of Side Chain Functional Groups

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ACS MACRO LETTERS 2021年第4期10卷 419-425页

作者： zhao, Bowen Liang, Ziqi Zhang, Ying Sui, Ying Shi, Yibo Zhang, xuwen Li, Miaomiao Deng, Yunfeng Geng, Yanhou Tianjin Univ Sch Mat Sci & Engn Tianjin 300072 Peoples R China Tianjin Univ Tianjin Key Lab Mol Optoelect Sci Tianjin 300072 Peoples R China Tianjin Univ Joint Sch Natl Univ Singapore & Tianjin Univ Int Campus Fuzhou 350207 Peoples R China

Direct arylation of 2,7-dibromofluorene with n-octyl, 6-diethoxylphosphorylhexyl, 6-(N,N-diethylamino)hexyl or 6-bromohexyl side chains and 1,2,4,5-tetrafluorobenzene (TFB) were conducted to investigate the effect of side chain functional groups on the coupling, and the resulting TFB-substituted fluorene derivatives were used as C-H monomers for the synthesis of water/alcohol soluble conjugated polymers (WSCPs) by direct arylation polycondensation (DArP). The direct arylation and DArP of the monomers carrying phosphonate and amino groups went on smoothly in typical DArP conditions, that is, Pd(OAc)(2)/(PBu2Me)-Bu-t-HBF4/base/DMAc and Pd-2(dba)(3)center dot CHCl3/P(o-MeOPh)(3)/pivalic acid/base/THF, and high molecular weight polymers with these groups were successfully synthesized. However, for fluorenemonomers with bromohexyl side chains, the target products could not be obtained from the above conditions but could be prepared in the absence of carboxylic acid additives in low polar solvents. With the above DArP-made polymers as cathode interfacial layers, high performance organic solar cells (OSCs) were successfully fabricated.

关键词： Monomers Organic reactions Organophosphorus compounds Condensation Polymers

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Effects of dietary resveratrol supplementation on hepatic and serum pro-/anti-inflammatory activity in juvenile GIFT tilapia, Oreochromis niloticus

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DEVELOPMENTAL AND COMPARATIVE IMMUNOLOGY 2017年 73卷 220-228页

作者： Zheng, Yao zhao, Zhixiang Wu, Wei Song, Chao Meng, Shunlong Fan, Limin Bing, xuwen Chen, Jiazhang Chinese Acad Fishery Sci Freshwater Fisheries Res Ctr Minist Agr Sci Observing & Expt Stn Fishery Resources & Envi Wuxi 214081 Jiangsu Peoples R China Nanjing Agr Univ Wuxi Fishery Coll Wuxi 214081 Jiangsu Peoples R China

Dietary resveratrol (RES) supplementation may have some pharmacological effects including anti inflammation. Previous studies have shown that Kupffer cell activation and apoptosis induction increases the transcription of pro- and anti-inflammatory cytokines. The main purpose of this study was to investigate the pro- and anti-inflammatory activities of 0.1 or 0.3 g/kg RES as a dietary supplement in juvenile freshwater tilapia (Oreochromis niloticus). The results showed that hepatic and serum immunoglobulin M (IgM) significantly decreased and increased while anti- and pro-inflammatory cytokines significantly increased and decreased, respectively, in the RES-treated groups. The expression of serum and hepatic IgM and anti-inflammatory cytokines [interleukin (IL)-10] and its inverse inhibitor interferon (IFN)-gamma significantly increased while pro-inflammatory cytokine transcription significantly decreased. Hematoxylin-eosin staining and scanning electron microscopy revealed intestinal deformation, irregular goblet cells, and apoptotic cells in the 03 g/kg RES groups. RES (0.3 g/kg) also induced necrosis, apoptosis, reduction in Kupffer cell number, compressed sinusoids, and deformation of epidermal cells in the liver of the treated groups. In conclusion, the results of the present study show that high doses of RES were absorbed in the gut and then damaged the liver and intestinal tissue. (C) 2017 Published by Elsevier Ltd.

关键词： Resveratrol Inflammatory cytokine Gene expression Apoptosis GIFT tilapia

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Probing the Interfacial Forces and Surface Interaction Mechanisms in Petroleum Production Processes

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Engineering 2022年第11期18卷 49-61页

作者： Diling Yang xuwen Peng Qiongyao Peng Tao Wang Chenyu Qiao Ziqian zhao Lu Gong Yueliang Liu Hao Zhang Hongbo Zeng Department of Chemical and Materials Engineering University of AlbertaEdmontonAB T6G 1H9Canada College of Petroleum Engineering China University of PetroleumBeijing 102249China

Despite the advances that have been made in renewable energy over the past decade,crude oil or petroleum remains one of the most important energy resources to the *** production presents many challenging issues,such as the destabilization of complex oil-water emulsions,fouling phenomena on pipelines and other facilities,and water *** problems are influenced by the molecular forces at the oil/water/solid/gas interfaces involved in relevant ***,we present an overview of recent advances on probing the interfacial forces in several petroleum production processes(e.g.,bitumen extraction,emulsion stabilization and destabilization,fouling and antifouling phenomena,and water treatment)by applying nanomechanical measurement technologies such as a surface forces apparatus(SFA)and an atomic force microscope(AFM).The interaction forces between bitumen and mineral solids or air bubbles in the surrounding fluid media determine the bitumen liberation and flotation efficiency in oil sands *** stability of complex oil/water emulsions is governed by the forces between emulsion drops and particularly between interface-active species(e.g.,asphaltenes).Various oil components(e.g.,asphaltenes)and emulsion drops interact with different substrate surfaces(e.g.,pipelines or membranes),influencing fouling phenomena,oil-water separation,and wastewater *** these intermolecular and interfacial forces has advanced the mechanistic understanding of these interfacial interactions,facilitating the development of advanced materials and technologies to solve relevant challenging issues and improve petroleum production *** challenges and suggestions on future research directions in the field are also presented.

关键词： Intermolecular and surface forces Interface Emulsion Colloids Fouling and antifouling Water treatment

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