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我国科学精英学术成长的影响因素研究——基于生命历程理论视角

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教育教学论坛 2024年第28期 14-19页

作者：杨馨缘上海戏剧学院教务处上海200040

以我国化学领域高被引科学家为例,借助生命历程理论的视角,将科学精英的学术职业生涯视为一个连续的生命历程,从科学精英生命历程中的关键性事件(博士教育经历、海外工作经历)和重要他人(博士或博士后导师、科研合作者)两个方面对影响... 详细信息

以我国化学领域高被引科学家为例,借助生命历程理论的视角,将科学精英的学术职业生涯视为一个连续的生命历程,从科学精英生命历程中的关键性事件(博士教育经历、海外工作经历)和重要他人(博士或博士后导师、科研合作者)两个方面对影响我国科学精英学术成长的因素进行分析,同时考虑到时代差异,对出生于不同时代科学精英的科研成果合作情况进行分析,以期为我国科学精英的培养、使用以及发展环境的营造提供参考。

关键词：科学精英学术成长高被引科学家

Contents of Phytosterols in Vegetables and Fruits Commonly Consumed in China

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Biomedical and Environmental Sciences 2008年第6期21卷 449-453页

作者： JUN-HUA HAN YUE-xin yang MEI-yuan FENG Institute of Nutrition and Food Safety Chinese Center for Disease Control and Prevention Beijing 100050 China

Objective To quantify five specific dietary phytosterols and phytostanols in vegetables and fruits commonly consumed in China. Methods A total of 34 different kinds of vegetables and 33 kinds of fruits were chosen according to the consuming habit of Chinese people. All the samples were purchased from two shops in Beijing. The contents of phytosterols （13-sitosterol, campesterol, stigmasterol, 13-sitostanol, and campestanol） were analyzed by GLC method which was established by our laboratory, and the total phytosterols were calculated. Results The total phytosterol content in vegetables ranged 1.1-53.7 mg/100 g edible portion. The highest concentration was found in pea, cauliflower, broccoli, and romaine lettuce. The phytosterol contents in fruits ranged 1.6-32.6 mg/100 g, the highest concentration was found in navel orange, tangerine, and mango. Conclusion The phytosterol contents in vegetables and fruits are not as high as those in edible oils, but because of the large amount of consumption, they also play an important role in increasing the people＇s phytosterols intake, indicating that increased intake of vegetables and fruits with higher phytosterol contents helps increase the phytosterol intake in China.

关键词： Phytosterol Vegetables Fruits China

Identification and Molecular Characterization of the Alkaloid Biosynthesis Gene Family in Dendrobium catenatum

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Phyton-International Journal of Experimental Botany 2024年第1期93卷 81-96页

作者： Liping yang xin Wan Runyang Zhou Yingdan yuan College of Horticulture and Landscape Architecture Yangzhou UniversityYangzhouChina Jiangsu Academy of Forestry NanjingChina Jiangsu yangzhou Urban Forest Ecosystem National Observation and Research Station YangzhouChina

As one of the main active components of Dendrobium catenatum, alkaloids have high medicinal value. The physicochemicalproperties, conserved domains and motifs, phylogenetic analysis, and cis-acting elements of the genefamily members in the alkaloid biosynthesis pathway of D. catenatum were analyzed by bioinformatics, and theexpression of the genes in different years and tissues was analyzed by qRT-PCR. There are 16 gene families,including 25 genes, in the D. catenatum alkaloid biosynthesis pathway. The analysis of conserved domains andmotifs showed that the types, quantities, and orders of domains and motifs were similar among members ofthe same family, but there were significant differences among families. Phylogenetic analysis indicated that thegene family members showed some evolutionary conservation. Cis-acting element analysis revealed that therewere a large number of light-responsive elements and MYB (v-myb avian myeloblastosis viral oncogene homolog)-related elements in these genes. qRT-PCR showed that expressions of gene family members involved in alkaloidsynthesis were different in different years and tissues of D. catenatum. This study provides a theoretical basisfor further exploration of the regulatory mechanisms of these genes in the alkaloid biosynthesis of D. catenatum.

关键词： Dendrobium catenatum gene family alkaloid biosynthesis

Dynamic recrystallization behavior and strengthening mechanism of a novel Mo-Ti_(3)AlC_(2) alloy at ultrahigh temperature

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Rare Metals 2024年第8期43卷 3946-3960页

作者： Lu yang xin-yuan Zheng yang Zhao Xi-Ran Wang Fang-Nao Xiao Shi-Zhong Wei School of Materials Science and Engineering Henan University of Science and TechnologyLuoyang 471023China National Joint Engineering Research Center for Abrasion Control and Molding of Metal Materials Henan University of Science and TechnologyLuoyang 471003China Department of Applied Mechanics Univ.Bourgogne FrancheComteFEMTO-ST InstituteCNRS/UF/ENSMM/UTBM25000BesangonFrance

Increasing the recrystallization temperature to achieve better high-temperature performance is critical in the development of molybdenum alloys for ultrahightemperature applications,such as the newest generation of multitype high-temperature nuclear *** this study,an innovative strategy was proposed to improve the performance of molybdenum alloys at high temperature by using the two-dimensional MAX(where M is an early transition metal,A is an A-group element and X is C or N)ceramic material Ti_(3)AlC_(2).The relationships between flow stress,strain rate and temperature were *** microstructure,distribution of misorientation and evolution of dislocations in the Mo-Ti_(3)AlC_(2) alloy were *** microscopic mechanism of the Ti_(3)AlC_(2) phase in the molybdenum alloy at high temperatures was *** experimental results showed that the peak flow stress of Mo-Ti_(3)AlC_(2) at 1600℃ reached 155 MPa,which was161.8% greater than that of pure *** activation energy of thermal deformation of Mo-Ti_(3)AlC_(2) was as large as537 kJ·mol~(-1),which was 17.6% more than that of pure *** recrystallization temperature reached 1600℃ or even *** topological reaction of the Ti_(3)AlC_(2) phase consumed a large amount of energy at high temperatures,resulting in increases in the deformation activation *** structures of AlTi_3 and Ti-O Magneli-phase oxides(Ti_nO_(2n-1)) were formed in-situ,which relied on kink bands and interlayer slip,resulting in many dislocations during ***,the special two-dimensional of the structure Ti_(3)AlC_(2) ceramic inhibited the recrystallization behavior of the Mo *** results of this study can provide theoretical guidance for the development of a new generation of molybdenum alloys for use in ultrahigh-temperature environments.

关键词： Mo alloy Two-dimensional reinforcement Dynamic recrystallization behavior Hot deformation Mechanical properties

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Knowledge Graph Enhanced Transformers for Diagnosis Generation of Chinese Medicine

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Chinese Journal of Integrative Medicine 2024年第3期30卷 267-276页

作者： WANG xin-yu yang Tao GAO Xiao-yuan HU Kong-fa School of Artificial Intelligence and Information Technology Nanjing University of Chinese MedicineNanjing210023China School of Information Management Nanjing UniversityNanjing210023China Jiangsu Collaborative Innovation Center of Traditional Chinese Medicine in Prevention and Treatment of Tumor Nanjing210023China Jiangsu Province Engineering Research Center of TCM Intelligence Health Service Nanjing210023China

Chinese medicine(CM)diagnosis intellectualization is one of the hotspots in the research of CM *** traditional CM intelligent diagnosis models transform the CM diagnosis issues into classification issues,however,it is difficult to solve the problems such as excessive or similar *** the development of natural language processing techniques,text generation technique has become increasingly *** this study,we aimed to establish the CM diagnosis generation model by transforming the CM diagnosis issues into text generation *** semantic context characteristic learning capacity was enhanced referring to Bidirectional Long Short-Term Memory(BILSTM)with Transformer as the backbone ***,the CM diagnosis generation model Knowledge Graph Enhanced Transformer(KGET)was established by introducing the knowledge in medical field to enhance the inferential *** KGET model was established based on 566 CM case texts,and was compared with the classic text generation models including Long Short-Term Memory sequence-to-sequence(LSTM-seq2seq),Bidirectional and Auto-Regression Transformer(BART),and Chinese Pre-trained Unbalanced Transformer(CPT),so as to analyze the model ***,the ablation experiments were performed to explore the influence of the optimized part on the KGET *** results of Bilingual Evaluation Understudy(BLEU),Recall-Oriented Understudy for Gisting Evaluation 1(ROUGE1),ROUGE2 and Edit distance of KGET model were 45.85,73.93,54.59 and 7.12,respectively in this *** with LSTM-seq2seq,BART and CPT models,the KGET model was higher in BLEU,ROUGE1 and ROUGE2 by 6.00–17.09,1.65–9.39 and 0.51–17.62,respectively,and lower in Edit distance by 0.47–*** ablation experiment results revealed that introduction of BILSTM model and prior knowledge could significantly increase the model ***,the manual assessment indicated that the CM diagnosis results of the KGET model used

关键词： Chinese medicine diagnosis knowledge graph enhanced transformer text generation

Polyoxometalates-derived ternary metal oxides electrocatalyst for N_(2) reduction under ambient conditions

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Tungsten 2024年第2期6卷 428-437页

作者： Meng-Le yang Zhong-xin Jin Xi-Xian Cao xin-Ming Wang Hui-yuan Ma Hai-Jun Pang Gui-xin yang The School of Material Science and Chemical Engineering Harbin University of Science and TechnologyHarbin 150040China

Accelerating the breaking of the nitrogen nonpolar bond(N≡N)is an important factor to improve the effi ciency of the electro-catalytic nitrogen reduction reaction(e-NRR).In this work,polyoxometalates-derived FeMo-based ternary oxide materials MoO_(2)-Mo_(4)O_(11)-FeMoO_(4)@X(abbreviated as MoFeO@X,X represents the synthesis temperature of 650,750 and 850℃)were designed and synthesized for e-NRR under ambient *** scanning electron microscopy images of MoFeO@750 show an ellipsoidal-like structure(0.86×0.6μm).The relatively large specifi c surface area,formation of multiple interfaces,together with the synergistic eff ect of iron and molybdenum bimetals,would make MoFeO@X catalyst more easily absorb and activate N_(2)in the ***,the synthesized MoFeO@750 shows an optimal NH_(3)production rate of 16.57μg·h^(−1)·mg cat.^(−1)and Faradaic effi ciency of 12.33%at−0.3 V versus reversible hydrogen electrode(ν***),with outstanding electrochemical and structural stability.

关键词： Polyoxometalates Electrocatalytic nitrogen reduction reaction Ternary oxide Electrocatalyst

A Real-time Prediction System for Molecular-level Information of Heavy Oil Based on Machine Learning

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China Petroleum Processing & Petrochemical Technology 2024年第2期26卷 121-134页

作者： yuan Zhuang Wang yuan Zhang Zhibo yuan Yibo yang Zhe Xu Wei Lin yang Yan Hao Zhou xin Zhao Hui yang Chaohe State Key Laboratory of Chemical Safety SINOPEC Research Institute of Safety Engineering Co.LtdQingdaoShandong 266000People’s Republic of China State Key Laboratory of Heavy Oil Processing China University of PetroleumQingdaoShandong 266580People’s Republic of China College of Chemistry and Chemical Engineering Ocean University of ChinaQingdaoShandong 266100People’s Republic of China

Acquiring accurate molecular-level information about petroleum is crucial for refining and chemical enterprises to implement the“selection of the optimal processing route”*** the development of data prediction systems represented by machine learning,it has become possible for real-time prediction systems of petroleum fraction molecular information to replace analyses such as gas chromatography and mass ***,the biggest difficulty lies in acquiring the data required for training the neural *** address these issues,this work proposes an innovative method that utilizes the Aspen HYSYS and full two-dimensional gas chromatography-time-of-flight mass spectrometry to establish a comprehensive training ***,a deep neural network prediction model is developed for heavy distillate oil to predict its composition in terms of molecular *** training,the model accurately predicts the molecular composition of catalytically cracked raw oil in a *** validation and test sets exhibit R2 values of 0.99769 and 0.99807,respectively,and the average relative error of molecular composition prediction for raw materials of the catalytic cracking unit is less than 7%.Finally,the SHAP(SHapley Additive ExPlanation)interpretation method is used to disclose the relationship among different variables by performing global and local weight comparisons and correlation analyses.

关键词： heavy distillate oil molecular composition deep learning SHAP interpretation method

Competition of Composition Fluctuation Modes in Weakly Segregated Salt-doped Symmetric Diblock Copolymers

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Chinese Journal of Polymer Science 2024年第9期42卷 1375-1385,I0008页

作者： yuan-xin Zhou Xian Kong South China Advanced Institute for Soft Matter Science and Technology School of Emergent Soft MatterSouth China University of TechnologyGuangzhou510640China Guangdong Provincial Key Laboratory of Functional and Intelligent Hybrid Materials and Devices South China University of TechnologyGuangzhou510640China

Salt-doped block copolymers have widespread applications in batteries,fuel cells,semiconductors,and various industries,where their properties crucially depend on phase separation ***,investigations into salt-doped diblock copolymers have predominantly focused on microphase separation,overlooking the segregation between ionic and polymeric *** study employs weak segregation theory to explore the interplay between phase separation dominated by the polymer-modulated mode and the salt-out-modulated mode,corresponding to microscopic and macroscopic phase separations,*** comparing diblock copolymers doped with salts to those doped with neutral solvents,we elucidate the significant role of charged species in modulating phase *** phase separation mode exhibits a transition between the polymer-modulated and salt-out-modulated modes at different *** systems doped with neutral solvents,this transition is stepwise,while in salt-ion-doped systems,it is *** a sufficiently large Flory-Huggins parameter between ions and polymers,the salt-out-modulated mode becomes dominant,promoting macrophase *** to the solvation effect of salt ions,salt-doped systems are more inclined to undergo microphase ***,we explore factors influencing the critical wavenumber of phase separation,including doping level and the Flory-Huggins parameters between two blocks and between ions and polymeric *** findings reveal that in a neutral solvent environment,these factors alter only the boundary between micro-and macro-phase separations,leaving the critical wavenumber unchanged in microphase separation ***,in a salt-doped environment,the critical wavenumber of microphase separation varies with these *** provides valuable insights into the pivotal role of electrostatics in the phase separation of salt-doped block copolymers.

关键词： Block copolymer Phase separation Field theory Salt-doped

Lath-like phases formed at an extremely high temperature in a Mg-RE(RE=rare earth)-Al alloy

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Rare Metals 2024年第8期43卷 3937-3945页

作者： Bo Deng Shu-Hui Lv Qiang yang Dong-Yue Zhao Jun-yuan Fan xin Qiu School of Materials Science and Engineering Changchun University of Science and TechnologyChangchun 130022China State Key Laboratory of Rare Earth Resource Utilization Changchun Institute of Applied ChemistryChinese Academy of SciencesChangchun 130022China Chongqing Research Institute Changchun University of Science and TechnologyChongqing 401135China

Thermal stable intermetallic particles are important for the heat resistance of magnesium(Mg)*** this work,many lath-like particles formed in α-Mg grains of a Mg-8Gd-3Sm-0.7Al casting alloy when heat-treated at 873 ***-resolution high-angle annular dark field scanning transmission electron microscopy(HAADF-STEM) characterizations indicate that most of them are Mg-containing Al_(2)(Gd,Sm),with the atomic ratio of Mg:Al:(Gd,Sm) being ~1:1:1;a small part of them with relatively wider thickness are long-period stacking ordered(LPSO) phases simultaneously containing both 14H and 18R *** followed common orientation relationships with Mg matrix as those reported in previous *** addition,many Mg laths were observed in the primary blocky Al_(2)(Gd,Sm) phase at grain boundaries,where the atomic ratio of Al:(Gd,Sm) in the Al_(2)(Gd,Sm) matrix was 2:***,density functional theory(DFT) calculations illustrated the detail structure of the re-constructed Mg/Al_(2)RE interface and simultaneously deduced the underlying reason for the re-dissolution of the newly formed Mg-containing Al_(2)(Gd,Sm) plates in α-Mg matrix.

关键词： Magnesium alloy HAADF-STEM Microstructures Intermetallic particles Orientation relationships Interfaces