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Petroleum Science 2020年第2期17卷 556-566页

作者： Shengzhu Zhang Xu Wang y.Frank cheng Jian Shuai China Academy.of Safety Science and Technology Beijing 100012China Department of Mechanical Engineering University of CalgaryCalgaryAB T2N 1N4Canada College of Safety and ocean Engineering China University of Petroleum(Beijing)Beijing 102249China

oil spill-induced vapor cloud explosions in a confined space can cause catastrophic *** this work,investigation was conducted on the catastrophic pipeline leak,oil spill,and the resulting vapor cloud explosion accident occurring in China in 2013 by modeling analysis,field surveys,and numerical *** total amount of the spilled oil was up to2044.4 m3 due to improper *** long residence time of the oil remaining in a confined space permitted the formation of explosive mixtures and caused the vapor cloud explosion.A numerical model was developed to estimate the consequence of the explosion based on volatilization testing *** results show that the death-leading zone and the glass-breaking zone could be 18 m and 92 m,respectively,which are consistent with the field *** severity.of the explosion is related to the amount of the oil spill,properties of oil,and volatilization *** is recommended that a comprehensive risk assessment be conducted to analyze the possible consequences upon oil spilling into a confined *** collection and ventilation measures should be taken immediately after the spill occurs to reduce the time for oil volatilization and prevent the mixture from reaching its explosive limit.

关键词： Pipeline leaking oil spill Vapor cloud explosion Confined space Consequence analysis

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教学的文化实践属性及三个基本认识向度

新疆师范大学学报（哲学社会科学版） 2025年第2期46卷 137-143页

作者：程良宏王芸新疆师范大学教育科学学院新疆高等教育发展研究中心新疆乌鲁木齐830017

教学不仅是知识传递行为,而且是具有文化交往和文化生产属性的实践活动。文本认为,从教学目的、教学主体和教学内容入手探析教学在知识传递传承背后的文化实践特质,是理解教学具有文化交往和文化生产属性的三个基本认识向度。因此,要深... 详细信息

教学不仅是知识传递行为,而且是具有文化交往和文化生产属性的实践活动。文本认为,从教学目的、教学主体和教学内容入手探析教学在知识传递传承背后的文化实践特质,是理解教学具有文化交往和文化生产属性的三个基本认识向度。因此,要深入体认教学作为一种特殊的文化交往和生产实践形态,明晰以文化人、以文育人的导引和践行为目的指引,以教师与学生为文化交往和文化生产的实践主体,以教学过程中对教材与师生文化的理解再造为文化实践的基本内容。

关键词：教学实践教学的文化属性文化生产

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失效的“压舱石”:经济安全化的现实转向

国际安全研究 2025年第1期43卷 133-154,159页

作者：高程部彦君中国社会科学院拉丁美洲研究所中国社会科学院大学国际政治经济学院北京100007 同济大学政治与国际关系学院上海200092

经济安全化是国家通过安全叙述将非安全的经济议题转化为安全议题的过程。在国家认为经济合作的收益将损害其在权力竞争中的整体所得时,或者在国家间政治外交关系遇到巨大震荡或冲击时,国家安全逻辑会超越经济逻辑而生效。此时,安全与... 详细信息

经济安全化是国家通过安全叙述将非安全的经济议题转化为安全议题的过程。在国家认为经济合作的收益将损害其在权力竞争中的整体所得时,或者在国家间政治外交关系遇到巨大震荡或冲击时,国家安全逻辑会超越经济逻辑而生效。此时,安全与经济问题在刻意煽动下交织碰撞,国家间密切的经贸关系不仅难以成为管控两国矛盾与分歧的“压舱石”,反而会被国家视作现存的“安全威胁”,成为某些国家中断或破坏双边政治经济联系的借口与手段。国家间存在的经济相互依赖关系也会随之成为安全化操纵国维护与拓展权力、进行地缘政治竞争和打击、操纵他国的战略性工具。因此,文章以存在紧密经济相互依赖的中美与俄欧关系为案例,在比较中美、俄欧之间不同经济安全化动因的基础上,分析经济安全化转向背后的选择逻辑,为中国更好地应对经济安全化挑战、更有针对性地发挥“经济压舱石”作用提供一定思考。

关键词：经济安全化经济压舱石国家安全经济相互依赖

Dielectric composites with a high and temperature-independent dielectric constant

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Journal of Advanced Ceramics 2012年第4期1卷 310-316页

作者： Xiaobing SHAN Lin ZHANG Xiqiao yANG Z-y.cheng Materials Research and Education Center Auburn UniversityAuburnAL 36849USA

Dielectric composites made using P(VDF-CTFE)88/12 mol%as polymer matrix and both micro-sized and nano-sized CaCu3Ti4o12(CCTo)particles as filler are *** composites exhibit high dielectric constant with a small dielectric *** importantly,it is found that the dielectric constant of these composites is almost independent of temperature from 25℃to 125℃.Comparing the composites made using micro-sized CCTo particles,the composites made using nano-sized CCTo particles exhibit a smaller dielectric *** dielectric properties of these composites indicate that the nano-sized CCTo particles have a smaller dielectric constant than the micro-sized CCTo particles.

关键词： dielectric constant composite CCTo P(VDF-CTFE) temperature dependence

Surface hydrophobicity: effect of alkyl chain length and network homogeneity

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Frontiers of Chemical Science and Engineering 2021年第1期15卷 90-98页

作者： Wenqian Chen Vikram Karde Thomas N.H.cheng Siti S.Ramli Jerry y.y.Heng Department of Chemical Engineering Imperial College LondonLondonSW72AZUK Department of Food Technology Faculty of Applied SciencesUniversiti Teknologi MARA(UiTM)Shah AlamSelangorMalaysia

Understanding the nature of hydrophobicity has fundamental importance in environmental *** spherical silica nanoparticles(diameter=369±7 nm)as the model material,the current study investigates the relationship between the alkyl chain network and *** alkyl silanes with different chain length(triethoxymethylsilane(C1)***(octyl)silane(C8))were utilised separately for the functionalisation of the *** contact angle and inverse gas chromatography results show that the alkyl chain length is essential for controlling hydrophobicity,as the octyl-functionalised nanoparticles were highly hydrophobic(water contact angle=150.6°±6.6°),whereas the methyl-functionalised nanoparticles were hydrophilic(i.e.,water contact angle=0°,similar to the pristine nanoparticles).The homogeneity.of the octyl-chain network also has a significant effect on hydrophobicity,as the water contact angle was reduced significantly from 148.4°±3.5°to 30.5°±1.0°with a methyl-/octyl-silane mixture(ratio=160:40µL·g^(–1) nanoparticles).

关键词： hydrophobicity surface energy wettability alkyl chain network silica nanoparticle

Modelling low carbon transition and economic impacts under SSPs and RCPs based on GTIMES

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Advances in Climate Change Research 2021年第6期12卷 858-870页

作者： yANG Lei SHI Jing-cheng CHEN Wen-ying James GLyNN Brian o GALLACHoIR Institute of Energy Environment and EconomyTsinghua UniversityBeijing100084China MaREI Centre for Energy Climate and MarineEnvironmental Research InstituteUniversity College CorkCorkT12 K8AFIreland School of Engineering University College CorkCorkT12 K8AFIreland

The simulation of global and regional energy system transition and its potential mitigation cost could intuitively reflect the need for earlier climate mitigation actions. To explore the possible transitions of global and regional energy system, this study applied a 14-region energy system model (GTIMES) with scenarios designed using Shared Socio-economic Pathways (SSPs) with Representative Concentration Pathways (RCPs), and detailed depicts the quantification of SSPs trajectories into GTIMES model. Modeling results show that: 1) Global energy-related Co_(2) emissions will reach 37–74 Gt by 2050 under reference scenarios, while they will decrease to 12–14 Gt under higher possibility pathways to reach 2 ℃ target, with ratios of non-fossil fuel round to 42%–46%. 2) Electrification level has to increase noticeably in regional transition with a global average level of about 44% to achieve significant emission reduction. 3) Higher level of mitigation cost would happen with the constraint mitigation target, as well as social and economic trajectories chosen. Therefore, following trajectories of sustainable development is necessary.

关键词： GTIMES model Shared social-economic pathways Co_(2)emission Energy consumption

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融合情感和常识知识的对话生成模型

计算机科学 2025年第1期52卷 307-314页

作者：程金凤蒋宗礼北京工业大学信息学部北京100124

随着深度学习技术的发展,开放域对话系统作为人机对话系统的重要分支也得到了快速发展。但目前开放域对话模型生成的回复语句依然存在同理心较差、多样性较低等问题。对此,提出一种融合情感和常识知识的对话生成模型。首先依据情感词典... 详细信息

随着深度学习技术的发展,开放域对话系统作为人机对话系统的重要分支也得到了快速发展。但目前开放域对话模型生成的回复语句依然存在同理心较差、多样性较低等问题。对此,提出一种融合情感和常识知识的对话生成模型。首先依据情感词典和常识知识图谱获取每个单词对应的常识知识向量,然后将该向量和单词本身的词嵌入向量一同输入编码器中进行编码,接着通过两阶段解码来生成回复语句:第一个解码阶段预测要生成单词的情感强度,并据此获得该单词对应的情感向量,第二阶段解码结合第一阶段编码的结果和已生成单词的词嵌入向量及其对应的常识知识向量作为输入,预测要生成的单词。实验结果表明,该模型生成的回复语句更具同理心和多样性,并且在PPL,BLEU,ACC和DISTINCT等指标上相比基线模型都有一定提升。

关键词：对话模型情感词典常识知识图谱两阶段解码情感强度

Preparation of Anhydrate Phosphogypsum Binders

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武汉理工大学学报 2010年第17期32卷 193-195,200页

作者： yANG M XIE y cheng J K PANG y School of Chemistry and Chemical Engineering Guizhou UniversityGuiyang 550003China

In this work,phosphogypsum(PG) with a small amount of lime was thermally pretreated at 450 ℃ to produce anhydrate gypsum for the purpose of searching new ways for utilization of waste PG. Additives,K2So4 and one selected seed crystal(SC),were used as activator for anhydrate PG. The hydration characteristics of the anhydrate PG binders were investigated by determination of the setting time,the ratio of hydrated anhydrate PG,the compressive strength development,and the microstructure of the hardenite. The resistance to water was studied by measuring mass loss of binders exposed to hydrodynamic water. Results suggest that activated by K2So4 and SC,anhydrate PG hydrates much more rapidly than that without additives. The anhydrate PG binder with K2So4 and SC has proper setting time and good strength developments. SEM photos show that the set binders have hydrated products of rodlike and regularly shaped crystals. Those crystals connected closely,and the hardenite has a compact structure,which is beneficial to the obtainment of good properties.

关键词： anhydrate PG binders activator hydration

Smurfs have“fused”into the asymmetric division of stem cells

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Protein & Cell 2011年第1期2卷 2-4页

作者： Steven y.cheng ying E.Zhang Department of Developmental Genetics Center for Regenerative MedicineNanjing Medical University140 Hanzhong RoadNanjing 210029China Laboratory.of Cellular and Molecular Biology National Cancer InstituteNational Institutes of Health37 Convent DriveBethesdaMD 20892USA

The asymmetric cell division is the way in which a stem cell divides into one daughter stem cell and one differentiated daughter *** process is one of the key principles of developmental biology that ensures the perpetual supply.of stem cells while allowing a particular cell lineage to be *** Drosophila oogenesis,the fate of the daughter stem cell produced from the asymmetric division of germline stem cells(GSCs)is specified by Decapentaplegic(Dpp),but the other daughter cell has almost equal access to the Dpp *** Dpp signaling is inactivated in the differentiated daughter cell has been a deep mystery until a recent study,led by Dahua Chen of the Institute of Zoology,China(Xia et al.,2010),showed that the Dpp receptor,Thick vein(Tkv),is degraded specifically in the differentiated daughter cell by an HECT-domain ubiquitin E3 ligase,Smurf,in conjunction with a serine-threonine kinase Fused(Fu).This finding is as much revealing as it is surprising,because up until now Fu is considered a core member of the Hedgehog signaling pathway.

关键词： daughter asymmetric fused

NumericalModeling of ElasticWave Propagation in a Fluid-Filled Borehole

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Communications in Computational Physics 2008年第1期3卷 33-51页

作者： Arthur C.H.cheng Joakim o.Blanch Cambridge GeoSciences 14090 Southwest FreewaySuite 300Sugar LandTX 77478USA Nexus GeoSciences 14090 Southwest FreewaySuite 240Sugar LandTX 77478USA previously at SensorWise Inc.2908 RodgerdaleHoustonTX 77042USA.

We review the methods of simulating elastic wave propagation in a *** considered two different approaches: a quasi-analytic approach using theDiscreteWavenumber SummationMethod, and the purely numerical Finite DifferenceMethod. We consider the special geometry.of the borehole and discuss the problem incylindrical coordinates. We point out some numerical difficulties that are particularlyunique to this problem in cylindrical coordinates.

关键词： Acoustic borehole numerical modeling.