Table of Content

20 December 2024 Volume 37 Issue 6

  

Oceanographic Science, Technology and Equipment

Ship heave motion prediction method based on wavelet transform and improved time series model

LIU Zhizhen, HUANG Lumeng, SUN Yapeng, ZHANG Ying, LIU Zhendong

Shandong Science. 2024, 37(6):  1-11.  doi:10.3976/j.issn.1002-4026.20240019

Abstract ( )   HTML ( )   PDF (6283KB) ( )  

Figures and Tables | References | Related Articles | Metrics

Lag in detecting ship heave motion signals severely affects the performance of ocean heave compensation systems. Therefore, accurate heave motion prediction can effectively improve the stability and real-time performance of these systems. To improve the engineering practicability of a heave motion prediction model, we designed an autoregressive time-series model featuring high calculation efficiency, simple programing, and a small accumulation error. Moreover, to further address the poor adaptability of the model to nonlinear and nonstationary complex sea conditions and long-term predictions, we developed a combined prediction model based on wavelet transform and improved autoregression using the wavelet multiscale analysis method and achieved online multistep prediction of heave motions by decomposing and transforming historical data, reconstructing sub-sequence prediction, and forecasting data synthesis. Finally, theoretical testing and experiments were conducted on stationary random waveforms and nonstationary waveforms measured on ships. The analysis results show that the combined model exhibits good prediction performance and can effectively reduce the control error of the ocean heave compensation system caused by the lag in the heave motion signal detection.

Optimization of structural parameters and oil removal effect of a self-induced vortex oil collector

ZHANG Ruihan, JIANG Lewen, WANG Yue, HAO Zongrui

Shandong Science. 2024, 37(6):  12-21.  doi:10.3976/j.issn.1002-4026.20240045

Abstract ( )   HTML ( )   PDF (4081KB) ( )  

Figures and Tables | References | Related Articles | Metrics

To achieve the best separation effect and oil phase collection efficiency, a self-induced vortex oil collector was designed to collect residual oil from the turbulent sea. The inlet flow angle and suction pipe insertion depth of the device were adjusted and optimized via numerical simulation calculations. By comparing the volume of oil phase remaining inside the device in the same operation time, we concluded that at an inlet flow angle of 20° and a suction pipe insertion depth of h/3, the device could maintain a high oil phase separation efficiency, suppress oil-water mixing, and reduce oil-water interface diffusion and impurities. After determining the optimal structure, we analyzed the oil removal effect of the device in different water surface environments by changing its inlet flow velocity. The higher the inlet flow velocity, the higher the performance of the device for collecting the oil phase and better its oil removal effect. In addition, the entire oil collection process occurs inside the device without being affected by the external environment, suggesting that the device can collect oil from complex water surface environments. Moreover, the main body of the device has no moving parts, hence, it relies solely on the baffle to guide the swirl for collecting the oil phase.

Traditional Chinese Medicine and Natural Active Products

Preparation and recognition property of molecularly imprinted covalent organic framework of chlorogenic acids

WANG Youdan, JI Wenhua, WANG Xiao

Shandong Science. 2024, 37(6):  22-30.  doi:10.3976/j.issn.1002-4026.20240002

Abstract ( )   HTML ( )   PDF (3392KB) ( )  

Figures and Tables | References | Related Articles | Metrics

In this study, an imine-linked molecularly imprinted covalent organic framework (MCOF) was successfully prepared using chlorogenic acids as the template. Adsorption isotherm, adsorption kinetics, and selective recognition capacity were utilized to assess the performance of the MCOF and its non-imprinted counterpart, the covalent organic framework (NCOF). MCOF exhibited good site accessibility, taking 15 min to attain 97.1% of the maximum adsorbing capacity. Compared with the selective adsorption capacity of the NCOF to the analogs of chlorogenic acids, the MCOF showed higher selectivity to a family of related molecules with a structure similar to that of chlorogenic acids. This study shows that the MCOF provides an innovative opportunity to develop a highly selective material for the extraction and separation of a family of molecules from a high polarity medium.

Quality evaluation of Ganoderma lucidum as a medicinal material based on polysaccharides and entropy-weighted TOPSIS

YANG Zhicheng, SUN Caihong, YE Guan

Shandong Science. 2024, 37(6):  31-41.  doi:10.3976/j.issn.1002-4026.20240044

Abstract ( )   HTML ( )   PDF (1933KB) ( )  

Figures and Tables | References | Related Articles | Metrics

A comprehensive quantitative model that evaluates Ganoderma lucidum as a medicinal material was established based on polysaccharides and entropy-weighted technique for order preference by similarity to ideal solution(TOPSIS) to provide a reference for the quality evaluation of G. lucidum as a medicinal material and selecting the best batches. Initially, the yield, sugar composition, total sugar content, protein content, and uronic acid content of crude polysaccharides were determined formultiple batches of G. lucidum medicinal materials from the same origin. Subsequently, the data were nondimensionalized. Finally, entropy-weighted TOPSIS was used to comprehensively evaluate the quality of G.lucidum polysaccharides from different batches to establish the optimal standard. The yield, component content detection, and cluster heat map analysis of the polysaccharides showed that the polysaccharide yield and the total sugar and uronic acid content of G. lucidum medicinal materials from different batches varied significantly, whereas differences in the sugar composition and protein content were relatively minor. Polysaccharide yield and intrinsic indicators of the G. lucidum medicinal materials were not related to their origin. Entropy weight analysis showed that the polysaccharide yield weight coefficient was the largest at 23.68%, followed by total sugar at 21.35% and uronic acid content at 13.24%. The TOPSIS ranking and grouping results showed that cultivated G. lucidum fruiting bodies and red G. lucidum polysaccharides had better comprehensive scores. The quality of G. lucidum medicinal materials differ widely among different batches from the same origin. Entropy-weighted TOPSIS based on multi-index comprehensive evaluation achieved rapid, efficient, and accurate optimization of the source for G. lucidum polysaccharide extractasa medicinal material and has broad application prospects in production and comprehensive quality evaluation. This study provides a reference for the quality evaluation of other Chinese medicinal and decoction materials.

Pharmacology and Toxicology

Prediction of anti-aging mechanism of Panax quinquefolius L. by network pharmacology and molecular docking

FAN Wei, SHEN Chuanlin, ZHANG Xuanming, DU Xingshuo, ZHAN Wen, SUN Chen, JIN Meng, LI Xiaobin, ZHANG Sichen, SUN Botong, HE Qiuxia

Shandong Science. 2024, 37(6):  42-50.  doi:10.3976/j.issn.1002-4026.20240005

Abstract ( )   HTML ( )   PDF (4085KB) ( )  

Figures and Tables | References | Related Articles | Metrics

The aim of this study was to explore the potential effective ingredients and mechanism of action of Panax quinquefolius L. in anti-aging based on network pharmacology and molecular docking. The anti-aging activity of P. quinquefolius L. was evaluated in a zebrafish aging model. The active ingredients of P. quinquefolius L. and their potential targets related to anti-aging were screened using databases, and protein-protein interaction networks (PPI) were mapped to screen core targets. Enrichment analysis and molecular docking verification of the core targets were performed. SA-β-Gal staining results showed that P. quinquefolius L. exerted significant anti-aging activity.Database screening identified 11 active ingredients and 53 potential core targets of P. quinquefolius L. in anti-aging, such as AKT1, STAT3, and JUN. The results of GO and KEGG analysis showed that the anti-aging effects of P. quinquefolius L. may involve factors including xenobiotic stimulus response, negative regulation of apoptotic processes, PI3K-AKT signaling pathway, ErbB signaling pathway. Molecular docking results showed that polyacetylene PQ-2 and PQ-2 were tightly bound with their core targets, and tight binding was also seen with AKT1 and HRAS with various active ingredients. P. quinquefolius L. may act on multiple targets such as AKT1, HRAS, and MAPK1 through polyacetylene PQ-2, PQ-2, and other ingredients, and then regulate multiple pathways such as endocrine resistance, ErbB signaling pathway, and other mechanisms to exert an anti-aging effect.Collectively, these dataprovide a theoretical basis for the application of P. quinquefolius L. in anti-aging.

Effects of Dioscorea opposita Thunb. polysacchariades on exercise-related fatigue in mice through the PI3K/AKT/Gsk-3β pathway

ZENG Ting, YANG Ran, LI Qingjun, GONG Yanan, WANG Shuzhen, LIU Qian

Shandong Science. 2024, 37(6):  51-58.  doi:10.3976/j.issn.1002-4026.20240034

Abstract ( )   HTML ( )   PDF (2727KB) ( )  

Figures and Tables | References | Related Articles | Metrics

This study aimed to investigate the antifatigue effects and mechanisms of Dioscorea opposita Thunb. polysaccharides (DTPs) on exercise-related fatigue in mice. In a mouse model of exercise fatigue where mice were subjected to exhaustive swimming and fatigue rotarod, changes in exhaustive swimming duration, body weight, fatigue metabolite accumulation, activity levels of related enzymes, liver tissue structure, and muscle glycogen (MuG) and liver glycogen (LG) contents were assessed. The results demonstrated that DTPs significantly prolonged the exhaustive swimming duration and reduced body weight loss, hepatic damage, and serum lactic acid (LD), blood urea nitrogen (BUN), and lactate dehydrogenase (LDH) levels in the mice. DTPs also significantly enhanced superoxide dismutase (SOD) activity and MuG and LG contents and significantly reduced aspartate aminotransferase (AST) levels. Additionally, in mice administered DTPs, the mRNA expression of phosphoinositide 3-kinase (PI3K) was significantly upregulated, whereas that of protein kinase B (AKT) and glycogen synthase kinase-3 (Gsk-3β) was significantly downregulated in skeletal muscle. Taken together, DTPs can reduce metabolite accumulation and ameliorate exercise fatigue by regulating the PI3K/AKT/Gsk-3β pathway to promote glycogen synthesis.

Microbiology of Agriculture

Study on the process research and quality analysis of Osmanthus craft beer

HAO Qian, MENG Dewen, LÜ Yuan, ZHAN Hangshan, WANG Chenghao, CHEN Siyou, LI Jie

Shandong Science. 2024, 37(6):  59-66.  doi:10.3976/j.issn.1002-4026.20240018

Abstract ( )   HTML ( )   PDF (2087KB) ( )  

Figures and Tables | References | Related Articles | Metrics

Craft beer has become a focus of attention for beer companies in recent years due to its unique flavor and mouthfeel, characterized by high malt concentration, alcohol content, and strong hop bitterness. Osmanthus, known for its pleasant and rich aroma, contains a large amount of active and healthy ingredients. Therefore, this paper aims to explore the difference in the quality of different Osmanthus content in craft beer. The process formulation of Osmanthus-infused craft beer is determined through the detection of physicochemical indicators, analysis of volatile components, and sensory evaluation. The experimental results show that the amount of Osmanthus added is positively correlated with the physicochemical indicators of craft beer, such as alcohol content, concentration, and acidity, while it is inversely proportional to fermentation. The volatile components of Osmanthus-infused craft beer are mainly alcohols and esters, contributing to a rich and intense aroma. Craft beer infused with 0.6% Osmanthus exhibits abundant and delicate foam, a refreshing and pure taste, a harmonious body, and no off-flavors or odors, presenting the typical aroma of Osmanthus.

New Materials

Comparative study on the common bipolar plate welding processes and their joint microstructures and performance

HOU Dongxu, YIN Ziqiang, REN Yuan, MA Xinqiang, CHENG Wei

Shandong Science. 2024, 37(6):  67-74.  doi:10.3976/j.issn.1002-4026.20240021

Abstract ( )   HTML ( )   PDF (2883KB) ( )  

Figures and Tables | References | Related Articles | Metrics

In order to study the welding methods suitable for metal bipolar plates, 0.1 mm 316L stainless steel was welded by four common bipolar plate welding methods : laser welding, vacuum diffusion welding, brazing and ultrasonic welding.The potentiodynamic polarization curves of four kinds of welded joints were measured by using CHI-604E electrochemical workstation. The electrochemical corrosion properties of four kinds of welded joints were compared, and the electrochemical corrosion behavior was analyzed by combining microstructure and chemical composition.It is found that the corrosion resistance of vacuum diffusion welded joints and laser welded joints is strong, and the corrosion resistance of ultrasonic welded joints and brazed joints is weak.The post-weld deformation of four kinds of welded specimens was measured by laser spectral confocal microscope. Under the action of fixture, the deformation of laser welded specimens was smaller than that of other specimens.The welding time and welding process used in the welding process of the four welding methods were compared.After comprehensive comparison, laser welding is finally determined as the best choice for these four common metal bipolar plate welding methods.

Adsorption of SF₆ decomposed gases and its electronic properties on a novel pristine two-dimensional GeO₂

YANG Le, SUN Wanwan, DING Lishun, ZENG Wentian

Shandong Science. 2024, 37(6):  75-82.  doi:10.3976/j.issn.1002-4026.20240038

Abstract ( )   HTML ( )   PDF (3530KB) ( )  

Figures and Tables | References | Related Articles | Metrics

SF₆ is widely used in high-voltage insulated equipment due to its excellent insulating properties. High-voltage insulated equipment faces the problem of insulation aging during its long-term operation, which can reduce the stability and safety of energy power equipment. When partial discharge occurs, SF₆ decomposes under high-voltage and temperature into various species, such as SO₂, SO₂F₂, HF, and H₂S. Based on the first principle, a novel two-dimensional semiconductor pristine GeO₂ monomolecular layer, which has a strong adsorption capacity for SF₆ decomposed gases, is proposed in this study. Results show that this pristine GeO₂ monomolecular layer provides an ideal amount of charge transfer and work function during the adsorption process. The detection of the SF₆ decomposed gases by the novel two-dimensional GeO₂, which is a gas-sensitive semiconductor material, allows us to identify the operational status and degree of insulation of high-voltage insulated equipment, which is crucial for maintaining the reliability and stability of power systems.

Research and application progress of phthalonitrile resin

ZHU Guanglai, YU Yitao, LIU Qiang, LIU Haiming, HOU Yantao, XU Chao, ZHANG Wei, JIANG Chuanxing, LI Yuanyue, PAN Xinjing, LI Bing, WANG Zhenhua

Shandong Science. 2024, 37(6):  83-93.  doi:10.3976/j.issn.1002-4026.20240029

Abstract ( )   HTML ( )   PDF (3925KB) ( )  

Figures and Tables | References | Related Articles | Metrics

Phthalonitrile resin is new type of high-temperature resistant thermosetting resin system that has attracted wide attention owing to its excellent thermal and oxidative stability, flame retardancy, and mechanical properties as well as low expansion coefficient, dielectric constant, and dielectric loss. To improve its manufacturability and meet stringent environmental performance requirements, extensive research has been conducted worldwide on the modification of the phthalonitrile system. This paper reviews the research progress of the phthalonitrile system from the aspects of molecular structure design and curing methods and mechanisms along with its applications in electrical components, adhesives, etc. Moreover, the paper discusses the opportunities and challenges faced by phthalonitrile as a new type of special functional resin material, aiming to provide insights for research in relevant fields.

Traffic and Transportation

Quantum computing-based optimization method for train short-turn routing with flexible composition

YUAN Ye, XU Hao, LU Xueyong, LI Wenxin, XU Huizhang, YANG Xin

Shandong Science. 2024, 37(6):  94-103.  doi:10.3976/j.issn.1002-4026.20240003

Abstract ( )   HTML ( )   PDF (2422KB) ( )  

Figures and Tables | References | Related Articles | Metrics

The joint optimization of train timetable and short-turn routing under the flexible composition mode are restricted by various factors such as train timetables, passenger dynamic equations, and train composition adaptability. The coupling of constraints increases the complexity of the problem, making it difficult to solve using traditional optimization methods.This paper introduces the quantum computing method to address the problem. We built a mixed-integer nonlinear programming model to minimize the number of gathered passengers across all stations along the transit line. Furthermore, we used the real coherent Ising machine(CIM) to solve this problem. The numerical results show that the real coherent Ising machine has obvious advantages in computing efficiency and optimization performance compared with other classical algorithms.

Object detection model YOLO-T for complex traffic scenarios

LIU Yu, GAO Shangbing, ZHANG Qintao, ZHANG Yingying

Shandong Science. 2024, 37(6):  104-115.  doi:10.3976/j.issn.1002-4026.20240047

Abstract ( )   HTML ( )   PDF (5610KB) ( )  

Figures and Tables | References | Related Articles | Metrics

To address the challenges posed by complex traffic scenarios, particularly congested roads where traffic objects are densely packed and often occlude each other and small-scale objects are detected inaccurately, a new object detection model called YOLO-T (You Only Look Once-Transformer) is proposed. First, the CTNet backbone network is introduced, which has a deeper network structure and multiscale feature extraction module compared with CSPDarknet53. Not only can it better learn the multilevel features of dense objects but can also improve the model’s ability to handle complex traffic scenarios. Moreover, it directs the model’s focus toward the feature information of small objects, thereby improving the detection performance for small-scale objects. Second, Vit-Block is incorporated, which integrates more features by parallelly combining convolution and Transformer. This approach balances the relevance of local and contextual information, thereby enhancing detection accuracy. Finally, the Reasonable module is added after the Neck network, introducing attention mechanisms to further improve the robustness of the object detection algorithm against complex scenarios and occluded objects. Experimental results indicate that compared with baseline algorithms, YOLO-T achieves a 1.92% and 12.78% increase in detection accuracy on the KITTI and BDD100K datasets, respectively. This enhancement effectively boosts detection performance in complex traffic scenarios and can assist drivers to better predict the behaviors of other vehicles, thus reducing the occurrence of traffic accidents.

Environment and Ecology

Prediction of effluent total nitrogen in wastewater treatment using LSTM neural network

YU Mingquan, SHI Haoming

Shandong Science. 2024, 37(6):  116-124.  doi:10.3976/j.issn.1002-4026.20240010

Abstract ( )   HTML ( )   PDF (3441KB) ( )  

Figures and Tables | References | Related Articles | Metrics

The effluent total nitrogen (TN) is one of the key indicators for assessing the biological denitrification performance of wastewater treatment plants(WWTPs). To mitigate the prevalent issue of excessive TN discharges from WTTPs, we proposed a real-time prediction model based on long short-term memory (LSTM) networks. We performed Pearson correlation analysis to determine model inputs and used grid search algorithm to optimize model hyperparameters. Then, we used the proposed model to predict the actual effluent TN in a WWTP in Chongqing and compared its predictive performance with that of traditional time-series models. Results indicate that the proposed model can effectively predict effluent TN with an average absolute error of 0.911 mg/L, an average root mean square error of 1.074 mg/L, and an average absolute percentage error of 11.28%. All of these performance indicators surpass those of the recurrent neural network and ARIMA models. The proposed model can serve as the foundation for effective monitoring of effluent TN.

Analysis of spatiotemporal characteristics of global precipitation at middle and low latitudes

WANG Qiuyan, SONG Xiuyu, YANG Fan, LI Yaoru

Shandong Science. 2024, 37(6):  125-134.  doi:10.3976/j.issn.1002-4026.20240013

Abstract ( )   HTML ( )   PDF (9391KB) ( )  

Figures and Tables | References | Related Articles | Metrics

Based on the monthly average global precipitation data from January 1982 to April 2022, this study discusses the spatial distribution and time series of mode one and mode two using the cyclostationary empirical orthogonal function (CSEOF) method; analyzes the spatial distribution, seasonal variation characteristics, and interannual variation characteristics of global marine precipitation at low and middle latitudes; and discusses the possible causes of these variations. Results show that the interannual variation of precipitation exhibits periodic characteristics, with the main areas experiencing variations being distributed in the tropical Pacific region; additionally, the spatial field of mode one demonstrates an east-west inverse phase distribution, which is stronger in winter than in summer. The seasonal variation of the spatial field of mode two is more complex than that of mode one, with the high-value positive and negative variability regions demonstrating an east-west inverse phase distribution in winter and negative variability regions dominating in summer with weaker intensity. ENSO has an important impact on the interannual variations of precipitation. The spatiotemporal variation characteristics of mode one are primarily affected by the ENSO phenomenon, while those of mode two are mainly affected by the El Niño Modoki phenomenon. The main precipitation variation characteristics are affected by the superposition of these two phenomena.