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Journal of Iron and Steel Research International 2024年第8期31卷 2002-2013页

作者： shuai Wang Jie Li Li-yang Zeng Xun-wei Zuo Nai-lu Chen yong-hua Rongg Shanghai Key Laboratory of Materials Laser Processing and Modification School of Materials Science and EngineeringShanghai Jiao Tong UniversityShanghai 200240China School of Materials Science and Engineering Shanghai Jiao Tong UniversityShanghai 200240China

The metastable retained austenite(RA)plays a significant role in the excellent mechanical performance of quenching and partitioning(Q&P)steels,while the volume fraction of RA(V_(RA))is challengeable to directly predict due to the complicated relationships between the chemical composition and process(like quenching temperature(Qr)).A Gaussian process regression model in machine learning was developed to predict V_(RA),and the model accuracy was further improved by introducing a metallurgical parameter of martensite fraction(fo)to accurately predict V_(RA) in Q&P *** developed machine learning model combined with Bayesian global optimization can serve as another selection strategy for the quenching temperature,and this strategy is very effcient as it found the"optimum"Qr with the maximum V_(RA) using only seven consecutive *** benchmark experiment also reveals that the developed machine learning model predicts V_(RA) more accurately than the popular constrained carbon equilibrium thermodynamic model,even better than a thermo-kinetic quenching-partitioning-tempering-local equilibrium model.

关键词： Q&P steel Retained austenite fraction Machine learning Quenching temperature Gaussian process regression model

Research progress in pharmacological effects of polyphenols in Areca catechu L.

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中国药理学与毒理学杂志 2021年第10期35卷 777-778页

作者： ZHANG Hao PAN Fei-bing MA Yun-feng ZHANG Dan-shen JING yong-shuai College of Chemistry and Pharmaceutical Engineering Hebei University of Science and TechnologyShijiazhuang 050018China Huachuang Institute of Areca Research-Hainan Haikou 570125China

Betel nut is the dry and mature seed of Areca catechu L.,which is originated in Malaysia and cultivated in Yunnan,Hainan and Taiwan and other tropical areas of *** is also known as big belly,binmen,olive seed,green seed and so *** nut is a dual-use resource for medicine and food,which was first contained in LI Dang′s Pharmaceutical *** nut tastes bitter,pungent,warm in nature,and belongs to the stomach and large intestine *** contains a variety of chemical components such as alkaloids,phenolic compounds,polysaccharides,fatty acids,amino acids, flavonoids, minerals, terpenoids, and steroids. It has the advantages of promoting digestion, lowering blood pres sure, anti-depression, anti-oxidation, anti-inflammatory, and anti-parasites, antibacterial and other activities. The content of total phenols in fresh fruits of areca nut was 31.1%, mainly including catechin, isorhamnetin, chrysopanthoxanthin, luteolin, tannin and other polyphenols. The commonly used methods for determination of polyphenols in areca are vanil lin titration potassium permanganate titration and potassium ferricyanide spectrophotometry. The main activities and mechanisms of areca polyphenols include: ① Antidepressant effect: polyphenols bind to monoamine oxidase type A (MAO-A) receptors that inhibit the production of neurotransmitters, thereby increasing the content of amine transmitters in the brain and playing a therapeutic effect on depression. ② Antioxidant effect: polyphenols contain multiple adjacent hydroxyl groups, which are easily oxidized and can effectively remove superoxide anion free radical, hydroxyl free radi cal, 1,1-diphenyl-2-picrylhydrazyl radical, showing good antioxidant activity. ③ Bacteriostatic effect: polyphenols can spe cifically bind to the surface of bacteria, thus achieving bacteriostatic effect. Studies have found that betel nut polyphenols have varying degrees of inhibitory effects on a variety of bacteria. ④ Inducing apoptosis of lymphocytes:

关键词： Areca catechu polyphenols pharmacological action scientific utilization

Research progress in mulberry leaf polysaccharide in treating diabetic nephropathy

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中国药理学与毒理学杂志 2021年第10期35卷 778-779页

作者： ZHANG Shi-lin JING yong-shuai ZHANG Dan-shen ZHENG Yu-guang WU Lan-fang College of Chemistry and Pharmaceutical Engineering Hebei University of Science and TechnologyShijiazhuang 050018China College of Pharmacy Hebei University of Chinese MedicineShijiazhuang 050200China

Diabetic nephropathy(DN)is one of the most common complications of *** is an important cause of diabetes disability and *** is a systemic metabolic *** its pathogenesis,the interaction of various cell activities and a large number of cytokine biological activities,the activation of signal pathways and so on are involved in the development of *** present,the clinical treatment of DN is mainly Western medicine,but it has limitations such as strong toxicity,high side effects and poor ***,the discovery of natural anti-DN substances has also become an important means to treat *** leaves are the dry leaves of Morus alba *** is not only a traditional Chinese medicine,but also a dual-purpose medicinal material for medicine and *** has the effects of dispelling wind and clearing heat,cooling blood and brightening eyes,tonifying and so *** leaf polysaccharide(MLP)is a kind of high molecular compound in mulberry *** has many pharmacological effects,such as hypoglycemic,antioxidant,anti-stress,anti-virus and so ***,the pharmacological effects of mulberry leaf polysaccharides on diabetic nephropathy are reviewed in this paper,so as to provide references for further research and *** pathogenesis of DN is complex,and the mechanism of renal injury has not been completely *** current studies believe that DN is closely related to heredity,abnormal glucose metabolism,abnormal lipid metabolism,microcirculation disorder,cytokine action,oxidative stress and so *** studies show that the pharmacological effects of mulberry leaf polysaccharide in the prevention and treatment of DN mainly include:①Effect on transforming factor-β1(TGF-β1):TGF-β1 has become an important cytokine involved in the formation of renal fibrosis by regulating cell proliferation and differentiation and the production of extracellular matrix(ECM).MLP can significantly inhibit TGF-β1 protein,and then inhibit the syn

关键词： mulberry leaf polysaccharide diabetic nephropathy TGF-β1 insulin receptor substrate resistin adipo⁃nectin receptor 1

Research progress in immune regulation mechanism of Polygonati Rhizoma polysaccharide

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中国药理学与毒理学杂志 2021年第10期35卷 779-780页

作者： ZHANG Ya-meng JING yong-shuai ZHANG Dan-shen ZHENG Yu-guang WU Lan-fang College of Chemistry and Pharmaceutical Engineering Hebei University of Science and TechnologyShijiazhuang 050018China College of Pharmacy Hebei University of Chinese MedicineShijiazhuang 050200China

Polygonati Rhizoma is the dry rhizome of Liliaceae plants Polygonatum kingianum coil ethemsl,Polygonatum sibiricum Redoute and Polygonatum cyrtonem *** tastes sweet and has a flat *** belongs to the spleen,lung and kidney *** Rhizoma contains a variety of chemical components,including polysaccharides,alkaloids,steroidal saponins,lignans,phytosterols,and so *** Rhizoma polysaccharide(PSP)is one of the main bioactive components of Polygonati *** is widely *** has the effects of enhancing immunity,anti-inflammatory,anti-virus and regulating blood *** recent years,the immunomodulatory function of PSP has been paid more and more attention by *** can play an immunomodulatory role through a variety of mechanisms.(1)Effects of PSP on innate immunity.①Macrophages have a strong ability to phagocytize and clear foreign *** polysaccharides bind to macrophage specific membrane receptors,the immune response will be officially ***264.7 cells can be activated by PSP MR and TLR4 mediated signal pathway to improve the pinocytosis and phagocytosis of RAW264.7 cells.②Natural killer cell(NK cell)is a very important immune cell in the *** is a non-specific immune killer cell naturally existing in the *** has the dual functions of immune regulation and *** was found that the signal pathway mediated by PSP CR3 and TRL2 may play a major role in the stimulation of NK cells.(2)Effects of PSP on adaptive immune response.①Lymphocytes can be divided into two forms:T cells and B cells due to different differentiation and maturation sites.T lymphocytes are the general name of thymus dependent lymphocytes.B lymphocytes differentiate and mature from animal bone marrow cells and exert their humoral immune function by secreting different *** was found that PSP could activate T/B lymphocytes and increase the ratio of CD4+/CD8+in lymph cells to promote the regulation of immune system.②Thymus an

关键词： polygonatum sibiricum polysaccharide immunoregulation mechanism

Pharmacological effects of volatileoil from Alpinia officinaruim in treating cardiovascular diseases

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中国药理学与毒理学杂志 2021年第10期35卷 761-762页

作者： CHENG Wen-jing JING yong-shuai ZHANG Dan-shen ZHENG Yu-guang WU Lan-fang College of Chemistry and Pharmaceutical Engineering Hebei University of Science and TechnologyShijiazhuang 050018China College of Pharmacology Hebei University of Chinese MedicineShijiazhuang 050200China

Galangal(Alpinia officinaruim Hance)is the rhizome of the perennial herb belonging to Zingiberaceae *** are many active components in galangal,such as volatile oil,flavonoids,terpenoids,phenylpropanoids and glycosides,among which the content of volatile oil is *** bioactivities of galangal volatile oil on health effect includesanti-inflammatory,anti-hypertension,anti-oxidation and prevention of cardiovascular *** disease(CVD)is a kind of diseases related to circulatory system,which is also called circulatory system *** the past decade,the number of people dying from CVD has increased by 12.5%worldwide,and it is now the leading cause of human death *** have shown that galangal volatile oil has good pharmacological effects in treating CVD.①Regulation of glucose and lipid metabolism:studies have found that abnormal lipid metabolism can lead to obesity,diabetes,CVD and other *** serum total triglyceride(TG)content in liver and serum will increase in patients with abnormal fat *** results showed that the volatile oil of galangal could increase the excretion of neutral cholesterol,significantly reduce liver TG and serum TG,and thus regulate glucose and lipid metabolism,prevent lipid deposition and prevent CVD.②Improving insulin resistance(IR):inhibition of inflammatory cytokines such as IL^(-1),IL-6 activation and expression of TNF-α,improves IR,thereby protecting myocardium from IR-mediated *** the establishment of endothelial cell injury model induced by high glucose in vitro,it was found that the volatile oil of galangal can significantly reduce the secretion of pro-inflammatory cytokines TNF-αand IL-8,and inhibit the expression of ICAM-1 and VCAM-1 induced by high glucose,suggesting that it has protective effect on endothelial dysfunction and inflammation induced by high glucose.③Regulate blood oxygenation:during acute myocardial hypoxia,the activity of free radical scavenging s

关键词： Alpinia officinaruim essential oil Cardiovascular disease pharmacological effect

Hyperbolic hierarchical graph attention network for knowledge graph completion

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High Technology Letters 2024年第3期30卷 271-279页

作者： XU Hao CHEN Shudong QI Donglin TONG Da YU yong CHEN shuai Institute of Microelectronics of Chinese Academy of Sciences Beijing 100029P.R.China University of Chinese Academy of Sciences Beijing 100049P.R.China

Utilizing graph neural networks for knowledge embedding to accomplish the task of knowledge graph completion(KGC)has become an important research area in knowledge graph ***,the number of nodes in the knowledge graph increases exponentially with the depth of the tree,whereas the distances of nodes in Euclidean space are second-order polynomial distances,whereby knowledge embedding using graph neural networks in Euclidean space will not represent the distances between nodes *** paper introduces a novel approach called hyperbolic hierarchical graph attention network(H2GAT)to rectify this ***,the paper conducts knowledge representation in the hyperbolic space,effectively mitigating the issue of exponential growth of nodes with tree depth and consequent information ***,it introduces a hierarchical graph atten-tion mechanism specifically designed for the hyperbolic space,allowing for enhanced capture of the network structure inherent in the knowledge ***,the efficacy of the proposed H2GAT model is evaluated on benchmark datasets,namely WN18RR and FB15K-237,thereby validating its *** H2GAT model achieved 0.445,0.515,and 0.586 in the Hits@1,Hits@3 and Hits@10 metrics respectively on the WN18RR dataset and 0.243,0.367 and 0.518 on the FB15K-237 *** incorporating hyperbolic space embedding and hierarchical graph attention,the H2GAT model successfully addresses the limitations of existing hyperbolic knowledge embedding models,exhibiting its competence in knowledge graph completion tasks.

关键词： hyperbolic space link prediction knowledge graph embedding knowledge graph completion(KGC)

The Effect of Nb on Mechanical Properties of Quenching and Partitioning Steels

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Journal of Iron and Steel Research International 2011年第S1期18卷 306-309页

作者： ZHU shuai,KANG yong-lin,REN Kang-kang,WANG Chuan (School of Materials Science and Engineering.University of Science and Technology Beijing,Beijing 100083,China) Univ Sci & Technol Beijing Sch Mat Sci & Engn Beijing 100083 Peoples R China

In order to study the effect of alloy elements on mechanical properties of quenching and partitioning steels,the Q and P heat treatments on different chemical composition steels were carried on in *** tensile test results indicated the strength of Nb+Ti-bearing steel was not increasing as expected,but lower than that of the Nb+Ti-free steel,and the elongation was raised to 26% from 9%.The Nb+Ti-bearing steel microstructures after tensile test were detected by TEM and found a certain amount of twins in the deformed microstructure while the deformed microstructure mainly was lath martensite in Nb+Ti-free steel,which means the addition of Nb and Ti elements could cause the twinning induced plasticity by inhibiting the phase transformation from austenite to *** on above analysis,adding trace Nb element could greatly increase the stacking fault energy of the retained austenite,which is beneficial to the formation of twins,and the formation of twins would lower the strength slightly and raise the elongation drastically.

关键词： quenching and partitioning twinning induced plasticity niobium stacking fault energy

Flotation separation of feldspar from quartz using sodium fluosilicate as a selective depressant

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Rare Metals 2024年第3期43卷 1288-1300页

作者： Xin Hu Xian-Ping Luo Zi-shuai Liu yong-Bing Zhang He-Peng Zhou Zhi-Zhao Yang Xue-Kun Tang Faculty of Resource and Environmental Engineering Jiangxi University of Science and TechnologyGanzhou341000China Yichun Lithium New Energy Industry Research Institute Jiangxi University of Science and TechnologyYichun336000China

The physical and chemical properties of feldspar and quartz are highly similar,thus they cannot be easily separated *** this work,the flotation separation of feldspar from quartz using sodium fluosilicate(Na_(2)SiF_(6);SF)as a selective depressant was ***,the influence mechanism of SF on the selective flotation separation of feldspar and quartz was investigated via flotation tests,chemical analysis of flotation solution,Fourier transform infrared spectroscopy(FTIR),X-ray photoelectron spectroscopy(XPS)and contact angle *** results of the flotation tests show that feld spar and quartz without SF treatment have good *** SF treatment,feldspar still has good floatability,whereas quartz has significantly reduced *** solution chemical analysis shows that the functional group plays an important role in depressing the quartz is[SiF_(6)]^(2-).FTIR,XPS and contact angle analysis results show that[SiF_(6)]^(2-)is adsorbed only on the surface of ***,a thin hydrophilic SiOF layer is generated on the surface,which interferes with the adsorption of the collector on the surface of the *** phenomenon leads to a significant reduction in quartz's ***,SF has a good ability to separate feldspar from quartz by flotation.

关键词： Flotation separation Depressants Sodium fluorosilicate Quartz Feldspar

Recent Progress of Earth Observation Satellites in China

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空间科学学报 2024年第4期44卷 731-740页

作者： HUANG Shusong QI Wenping ZHANG shuai XIA Tian WANG Jingqiao ZENG yong China Centre for Resources Satellite Data and Application Beijing 100094

Currently,China has 32 Earth observation satellites in *** satellites can provide various data such as optical,multispectral,infrared,and *** spatial resolution of China Earth observation satellites ranges from low to medium to *** satellites possess the capability to observe across multiple spectral bands,under all weather conditions,and at all *** data of China Earth observation satellites has been widely used in fields such as natural resource detection,environmental monitoring and protection,disaster prevention and reduction,urban planning and mapping,agricultural and forestry surveys,land survey and geological prospecting,and ocean forecasting,achieving huge social *** article introduces the recent progress of Earth observation satellites in China since 2022,especially the satellite operation,data archiving,data distribution and data coverage.

关键词： China Earth Observation Satellites Satellite operation Data archiving Data distribution Data coverage

基于分层卷积深度学习系统的植物叶片识别研究

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北京林业大学学报 2016年第9期38卷 108-115页

作者：张帅淮永建北京林业大学信息学院

深度学习已成为图像识别领域的研究热点。本文以植物叶片图像识别为研究对象,对单一背景和复杂背景图像分别给出了优化预处理方案;设计了一个8层卷积神经网络深度学习系统分别对Pl@ant Net叶片库和自扩展的叶片图库中33 293张简单背景... 详细信息

深度学习已成为图像识别领域的研究热点。本文以植物叶片图像识别为研究对象,对单一背景和复杂背景图像分别给出了优化预处理方案;设计了一个8层卷积神经网络深度学习系统分别对Pl@ant Net叶片库和自扩展的叶片图库中33 293张简单背景和复杂背景叶片图像进行训练和识别,并与传统基于植物叶片多特征的识别方法进行了比较分析。实验证明:本文提供的CNN+SVM和CNN+Softmax分类器识别方法对单一背景叶片图像识别率高达91.11%和90.90%,识别复杂背景叶片图像的识别率也能高达34.38%,取得了较好的识别效果。利用本文实现的分层卷积深度学习识别系统在数据量大而无法做出更多优化的情况下,叶片图像的识别率更高,尤其是针对复杂背景下的叶片图像,取得了极佳的识别效果。

关键词：植物识别叶片图像特征提取支持向量机深度学习