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粤东沿海地区锡和钨成矿花岗岩地质地球化学特征的对比

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矿产与地质 1988年第S1期 30-38页

作者：肖振宇岳书仓中国有色金属工业总公司广东地质研究所合肥工业大学地质系

粤东沿海地区与锡钨矿化有关的花岗岩可划分为锡成矿花岗岩和钨成矿花岗岩。二者皆为燕山期构造—岩浆作用的产物,属地壳物质物重熔—深熔成因。锡成矿花岗岩形成于燕山中期,主要分布于潮安—海丰以东地区。岩性主要为二长花岗岩,岩石... 详细信息

粤东沿海地区与锡钨矿化有关的花岗岩可划分为锡成矿花岗岩和钨成矿花岗岩。二者皆为燕山期构造—岩浆作用的产物,属地壳物质物重熔—深熔成因。锡成矿花岗岩形成于燕山中期,主要分布于潮安—海丰以东地区。岩性主要为二长花岗岩,岩石相对富Al2O3、CaO以及Sn、Pb、Zn、Cu等微量元素。钨成矿花岗岩形成于燕山中晚期,主要分布在靠近莲花山断裂带地区。岩性主要为黑云母花岗岩,岩石相对富SiO2以及W、Be、F等微量元素,源岩特征的不同,是造成两种成矿花岗岩地质地球化学特征差异的根本原因。

关键词：成矿花岗岩黑云母粤东沿海地球化学特征花岗岩体地质

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连续油管滚筒多层缠绕力学分析与试验研究

石油矿场机械 2023年第1期52卷 15-23页

作者：李心成谢猛岳书常于晓刘伟强烟台杰瑞石油装备技术有限公司山东烟台264034

为了研究多层连续油管缠绕工况下滚筒的受力特性,通过理论分析得到滚筒筒身径向力、滚筒辐板轴向力及多层缠绕系数的计算方法。以某型号连续油管运输滚筒为例,计算得到相关力学参数。通过有限元仿真及应力-应变测试,对理论计算方法进行... 详细信息

为了研究多层连续油管缠绕工况下滚筒的受力特性,通过理论分析得到滚筒筒身径向力、滚筒辐板轴向力及多层缠绕系数的计算方法。以某型号连续油管运输滚筒为例,计算得到相关力学参数。通过有限元仿真及应力-应变测试,对理论计算方法进行验证。结果表明:仿真与试验结果趋于一致,验证了理论计算方法的合理性;连续油管滚筒筒身所受径向力随缠绕层数的增加而增大,但增幅逐渐趋缓;滚筒辐板所受轴向力随缠绕层数的增加而增大,且二者呈近似的线性关系。为了提高工程计算的效率,将多层缠绕系数应用于工程简化计算中,为设计满足复杂工况的滚筒提供可靠的技术手段。

关键词：连续油管多层缠绕有限元分析应力应变试验多层缠绕系数

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Data quantity governance for machine learning in materials science

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National Science Review 2023年第7期10卷 234-250页

作者： yue Liu Zhengwei Yang Xinxin Zou shuchang Ma Dahui Liu Maxim Avdeev Siqi Shi School of Computer Engineering and Science Shanghai University Shanghai Engineering Research Center of Intelligent Computing System Australian Nuclear Science and Technology Organisation School of Chemistry The University of Sydney State Key Laboratory of Advanced Special Steel School of Materials Science and Engineering Shanghai University Materials Genome Institute Shanghai University

Data-driven machine learning(ML) is widely employed in the analysis of materials structure-activity relationships,performance optimization and materials design due to its superior ability to reveal latent data patterns and make accurate ***,because of the laborious process of materials data acquisition,ML models encounter the issue of the mismatch between a high dimension of feature space and a small sample size(for traditional ML models) or the mismatch between model parameters and sample size(for deep-learning models),usually resulting in terrible ***,we review the efforts for tackling this issue via feature reduction,sample augmentation and specific ML approaches,and show that the balance between the number of samples and features or model parameters should attract great attention during data quantity *** this,we propose a synergistic data quantity governance flow with the incorporation of materials domain *** summarizing the approaches to incorporating materials domain knowledge into the process of ML,we provide examples of incorporating domain knowledge into governance schemes to demonstrate the advantages of the approach and *** work paves the way for obtaining the required high-quality data to accelerate materials design and discovery based on ML.

关键词： machine learning data governance data quantity materials science

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连续油管注入头夹持系统碰撞研究

机械工程师 2023年第4期 96-99,104页

作者：李先策李心成刘伟强于晓岳书常烟台杰瑞石油装备技术有限公司山东烟台264003

连续油管注入头夹持系统中的夹持块轴承出现过碰撞碎裂的情况,作为减振部件夹持块垫片的刚度很重要。文中基于动力学基本理论,构建了连续油管注入头夹持系统多体动力学模型。在考虑系统刚度的前提下,针对夹持块垫片刚度对夹持块轴承和... 详细信息

连续油管注入头夹持系统中的夹持块轴承出现过碰撞碎裂的情况,作为减振部件夹持块垫片的刚度很重要。文中基于动力学基本理论,构建了连续油管注入头夹持系统多体动力学模型。在考虑系统刚度的前提下,针对夹持块垫片刚度对夹持块轴承和滑道板碰撞力的影响做了对比分析;同时,在不同的夹持块垫片厚度下对单个夹持块轴承进行了瞬态动力学碰撞分析。研究结果表明:由于链轮多边形效应,夹持块进入滑道板区域时轴承会与滑道板发生碰撞,滑道板端部采用倒圆弧设计能有效减缓夹持块轴承受到的横向冲击;合适的夹持块垫片刚度与厚度能有效起到减缓夹持块轴承与滑道板碰撞冲击的作用。

关键词：注入头夹持系统夹持块垫板夹持块轴承多边形效应冲击

AE-TPGG:a novel autoencoder-based approach for single-cell RNA-seq data imputation and dimensionality reduction

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Frontiers of Computer Science 2023年第3期17卷 217-234页

作者： shuchang ZHAO Li ZHANG Xuejun LIU MIIT Key Laboratory of Pattern Analysis and Machine Intelligence College of Computer Science and TechnologyNanjing University of Aeronautics and AstronauticsNanjing 211106China Collaborative Innovation Center of Novel Software Technology and Industrialization Nanjing 210023China College of Computer Science and Technology Nanjing Forestry UniversityNanjing 210037China

Single-cell RNA sequencing(scRNA-seq)technology has become an effective tool for high-throughout transcriptomic study,which circumvents the averaging artifacts corresponding to bulk RNA-seq technology,yielding new perspectives on the cellular diversity of potential superficially homogeneous *** various sequencing techniques have decreased the amplification bias and improved capture efficiency caused by the low amount of starting material,the technical noise and biological variation are inevitably introduced into experimental process,resulting in high dropout events,which greatly hinder the downstream *** the bimodal expression pattern and the right-skewed characteristic existed in normalized scRNA-seq data,we propose a customized autoencoder based on a twopart-generalized-gamma distribution(AE-TPGG)for scRNAseq data analysis,which takes mixed discrete-continuous random variables of scRNA-seq data into account using a twopart model and utilizes the generalized gamma(GG)distribution,for fitting the positive and right-skewed continuous *** adopted autoencoder enables AE-TPGG to captures the inherent relationship between *** addition to the ability of achieving low-dimensional representation,the AETPGG model also provides a denoised imputation according to statistical characteristic of gene *** on real datasets demonstrate that our proposed model is competitive to current imputation methods and ameliorates a diverse set of typical scRNA-seq data analyses.

关键词： scRNA-seq autoencoder TPGG data imputation dimensionality reduction

Application of Fe(Ⅵ)in abating contaminants in water:State of art and knowledge gaps

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Frontiers of Environmental Science & Engineering 2021年第5期15卷 7-27页

作者： shuchang Wang Binbin Shao Junlian Qiao Xiaohong Guan State Key Laboratory of Pollution Control and Resources Reuse College of Environmental Science and EngineeringTongji UniversityShanghai200092China Shanghai Institute of Pollution Control and Ecological Security Shanghai200092China International Joint Research Center for Sustainable Urban Water System Tongji UniversityShanghai200092China

The past two decades have witnessed the rapid development and wide application of Fe(Ⅵ)in the field of water de-contamination because of its environmentally benign ***(Ⅵ)has been mainly applied as a highly efficient oxidant/disinfectant for the selective elimination of *** in situ generated iron(III)(hydr)oxides with the function of adsorption/coagulation can further increase the removal of contaminants by Fe(Ⅵ)in some *** of the limitations of Fe(Ⅵ)per se,various modified methods have been developed to improve the performance of Fe(Ⅵ)oxidation *** on the published literature,this paper summarized the current views on the intrinsic properties of Fe(Ⅵ)with the emphasis on the self-decay mechanism of Fe(Ⅵ).The applications of Fe(Ⅵ)as a sole oxidant for decomposing organic contaminants rich in electron-donating moieties,as a bi-functional reagent(both oxidant and coagulant)for eliminating some special contaminants,and as a disinfectant for inactivating microorganisms were systematically ***,the difficulties in synthesizing and preserving Fe(Ⅵ),which limits the large-scale application of Fe(Ⅵ),and the potential formation of toxic byproducts during Fe(Ⅵ)application were *** paper also systematically reviewed the important nodes in developing methods to improve the performance of Fe(Ⅵ)as oxidant or disinfectant in the past two decades,and proposed the future research needs for the development of Fe(Ⅵ)technologies.

关键词： Ferrate Oxidation Disinfection Coagulation Enhancement

Generative artificial intelligence and its applications in materials science:Current situation and future perspectives

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Journal of Materiomics 2023年第4期9卷 798-816页

作者： yue Liu Zhengwei Yang Zhenyao Yu Zitu Liu Dahui Liu Hailong Lin Mingqing Li shuchang Ma Maxim Avdeev Siqi Shi School of Computer Engineering and Science Shanghai UniversityShanghai200444China State Key Laboratory of Advanced Special Steel School of Materials Science and EngineeringShanghai UniversityShanghai200444China Materials Genome Institute Shanghai UniversityShanghai200444China Shanghai Engineering Research Center of Intelligent Computing System Shanghai200444China Australian Nuclear Science and Technology Organisation Sydney2232Australia School of Chemistry The University of SydneySydney2006Australia

Generative Artificial Intelligence(GAI)is attracting the increasing attention of materials community for its excellent capability of generating required *** the introduction of Prompt paradigm and reinforcement learning from human feedback(RLHF),GAI shifts from the task-specific to general pattern gradually,enabling to tackle multiple complicated tasks involved in resolving the structure-activity ***,we review the development status of GAI comprehensively and analyze pros and cons of various generative models in the view of *** applications of task-specific generative models involving materials inverse design and data augmentation are also *** ChatGPT as an example,we explore the potential applications of general GAI in generating multiple materials content,solving differential equation as well as querying materials ***,we summarize six challenges encountered for the use of GAI in materials science and provide the corresponding *** work paves the way for providing effective and explainable materials data generation and analysis approaches to accelerate the materials research and development.

关键词： Machine learning Artificial intelligence Generative artificial intelligence Materials science Novel materials discovery Deep learning

Recent progress of carbon-based metal-free materials in thermal-driven catalysis

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Journal of Energy Chemistry 2021年第7期30卷 318-335页

作者： shuchang Wu Linhui Yu Guodong Wen Zailai Xie Yangming Lin School of Pharmaceutical and Materials Engineering Taizhou UniversityTaizhou 318000ZhejiangChina Max Planck Institute for Chemical Energy Conversion Stiftstrasse 34-36Mülheim an der Ruhr 45470Germany Institute of Metal Research Chinese Academy of SciencesShenyang 110016LiaoningChina Fujian Provincial Key Laboratory of Electrochemical Energy Storage Materials Fuzhou UniversityFuzhou 350016FujianChina

The carbon-based metal-free materials as catalysts(named as carbocatalysts) have been attracting tremendous attentions in electric-,solar-and thermal-driven reactions *** to electrocatalysis and photocatalysis,the thermal-driven catalysis(thermocatalysis) including liquid phase and gas phase reactions involves wider scope and is relatively easy to realize practical large-scale *** the past several years,some striking achievements on the design of new carbon-based metal-free materials with well-defined structures and heteroatom groups as well as the revelation of new reaction mechanisms and active sites in thermocatalysis have been ***,comparative discussions regarding these recent achievements have been rarely *** this review,we systematically summarize and discuss six kinds of carbocatalysts and their applications in *** materials include typical oxygen-attached carbon,surface modified carbon(graft with certain organic compounds),mono-doped carbon,co-doped carbon,carbon nitride and materials with carbon as *** new reaction processes as well as the related reaction mechanisms,active sites and intermediates are reviewed ***,an outlook on the in-depth investigation of the metalfree carbocatalysis in the future is provided.

关键词： Carbocatalysis Metal-free Thermal-driven catalysis Active sites

Impacts of land surface darkening on frozen ground and ecosystems over the Tibetan Plateau

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Science China Earth Sciences 2024年第10期67卷 3213-3225页

作者： shuchang TANG Tao WANG Dan LIU Tandong YAO Shilong PIAO Sino-French Institute for Earth System Science College of Urban and Environmental SciencesPeking UniversityBeijing 100101China State Key Laboratory of Tibetan Plateau Earth System Resources and EnvironmentInstitute of Tibetan Plateau ResearchChinese Academy of SciencesBeijing 100101China

Tibetan Plateau(TP) is known as the “Third Pole” of the Earth. Any changes in land surface processes on the TP can have an unneglectable impact on regional and global climate. With the warming and wetting climate, the land surface of the TP saw a darkening trend featured by decreasing surface albedo over the past decades, primarily due to the melting of glaciers, snow,and greening vegetation. Recent studies have investigated the effects of the TP land surface darkening on the field of climate, but these assessments only address one aspect of the feedback loop. How do these darkening-induced climate changes affect the frozen ground and ecosystems on the TP? In this study, we investigated the impact of TP land surface darkening on regional frozen ground and ecosystems using the state-of-the-art land surface model ORCHIDEE-MICT. Our model results show that darkening-induced climate changes on the TP will lead to a reduction in the area of regional frozen ground by 1.1×10~4±0.019×10~4km~2, a deepening of the regional permafrost active layer by 0.06±0.0004 m, and a decrease in the maximum freezing depth of regional seasonal frozen ground by 0.06±0.0016 m compared to the scenario without TP land surface ***, the darkening-induced climate change on the TP will result in an increase in the regional leaf area index and an enhancement in the regional gross primary productivity, ultimately leading to an increase in regional terrestrial carbon stock by0.81±0.001 PgC. This study addresses the remaining piece of the puzzle in the feedback loop of TP land surface darkening, and improves our understanding of interactions across multiple spheres on the TP. The exacerbated regional permafrost degradation and increasing regional terrestrial carbon stock induced by TP land surface darkening should be considered in the development of national ecological security barrier.

关键词： Tibetan Plateau Albedo Land surface darkening Frozen ground Ecosystem