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疏水沉降地层竖向可缩性井壁附加力分布规律研究

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岩土力学 2007年第3期28卷 471-475页

作者：程桦苏俊姚直书安徽理工大学土木系湖北工学院武汉431000

通过数值分析和模型试验研究,揭示了竖向可缩性井壁附加力分布规律。研究表明,可缩性井壁可有效衰减附加力和井壁截面轴向应力;与单一可缩接头相比,设置两个可缩接头衰减附加力更为有效;提出的可缩接头设置优化原则,对科学、合理地设计... 详细信息

通过数值分析和模型试验研究,揭示了竖向可缩性井壁附加力分布规律。研究表明,可缩性井壁可有效衰减附加力和井壁截面轴向应力;与单一可缩接头相比,设置两个可缩接头衰减附加力更为有效;提出的可缩接头设置优化原则,对科学、合理地设计竖向可缩性井壁具有重要的指导意义。

关键词：沉降地层可缩井壁附加力

Enantioselective reductive conjugate alkenylation of α,β-enones with keto alkenyl acetates by nickel catalysis

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Science China Chemistry 2025年第1期68卷 157-162页

作者： Rong-De He Yun-Lei Luo Qiu-Quan Pan Qi-Wei yao Xing-Zhong shu State Key Laboratory of Applied Organic Chemistry College of Chemistry and Chemical Engineering Lanzhou University

Reactions involving alkenyl acetates offer cost-effective and environmentally friendly routes for alkene synthesis, yet their asymmetric variant remains elusive. Concurrently, asymmetric conjugate alkenylation predominantly centered on nucleophilic addition using alkenyl–M. This manuscript presents an asymmetric reductive conjugate alkenylation reaction involving alkenyl acetates. The method facilitates the enantioselective addition of keto alkenyl groups to α,β-enones, resulting in the formation of unsaturated diketones—a class of useful structural motifs that are challenging to access otherwise. The use of electron-rich Pyroxy ligand is essential for achieving both high reaction efficiency and enantioselectivity.

关键词： nickel alkenylation asymmetric cross-coupling alkenes

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柴油温度对喷孔内流动特性影响的仿真分析

浙江大学学报（工学版） 2015年第5期49卷 938-943页

作者：谢阳姚子澍麻剑罗麒元许沧粟浙江大学动力机械及车辆工程研究所浙江杭州310027 浙江大学城市学院工程学院浙江杭州310015

为研究柴油温度对真实喷孔内流动特性的影响,对柴油在喷油嘴喷孔内部的流动进行三维数值仿真.利用计算流体动力学(CFD)软件模拟得到不同燃油温度和背压条件下燃油的质量流量、有效喷射速度、空穴断面分布与无量纲流动参数,并进行分析.... 详细信息

为研究柴油温度对真实喷孔内流动特性的影响,对柴油在喷油嘴喷孔内部的流动进行三维数值仿真.利用计算流体动力学(CFD)软件模拟得到不同燃油温度和背压条件下燃油的质量流量、有效喷射速度、空穴断面分布与无量纲流动参数,并进行分析.结果表明:温度越高,背压越低,更容易进入临界超空穴状态;在进入超空穴状态之后,喷孔内的超空穴现象加剧有效喷射速度的升高,并且随着燃油温度上升,有效速度增加了6%;雷诺数随温度上升而上升,空穴数随着雷诺数的增加而呈指数下降,而流量系数在空穴发展阶段维持不变.

关键词：燃油温度空穴喷孔孔内流动数值模拟

The composition of magmatic-hydrothermal fluids and their related metal mineralization

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Science China Earth Sciences 2025年第1期68卷 208-225页

作者： Qihai shu Jun DENG State Key Laboratory of Geological Processes and Mineral Resources School of Earth Sciences and Resources China University of Geosciences Frontiers Science Center for Deep-time Digital Earth China University of Geosciences

Magmatic hydrothermal deposits are important sources of many bulk, precious, and rare metals, and have attracted interest from both academic and industrial communities. However, it is still unclear if the major enrichment of the ore-forming metals occurs in the parental magma source region, during the magma evolution, or after the fluid exsolution. Fluid inclusions trapped in hydrothermal minerals crystallized in the early, high-temperature stage before metal precipitation record information close to that of the initially exsolved magmatic fluids, which are helpful in revealing whether the metals have been already significantly enriched prior to the hydrothermal stage. In this study, available compositional data of such early-stage fluid inclusions from magmatic hydrothermal systems globally have been compiled. The results indicate that the concentrations of Cu,Sn, and W respectively from the Cu-, Sn-, and W-mineralized fluids are significantly higher than the hydrothermal systems that do not produce ores with the corresponding metals. This suggests that Cu, Sn, and W could have already been enriched in the magma source and/or magma evolution stage. The Mo concentrations show no difference between Mo-mineralized and Mobarren fluid systems, indicating no significant pre-enrichment in the source region or during the magma evolution. This also implies that an efficient collection of Mo from a large volume of magmas is required to account for the formation of a large Mo deposit. Almost all the hydrothermal fluids contain high concentrations of Fe and Zn-Pb, but only a few of them eventually form Fe or Zn-Pb deposits, reflecting an important role of the hydrothermal evolution process on the selective metal *** above results indicate that different metals are enriched in different stages of a magmatic hydrothermal system, and that the major roles played in the formation of a deposit vary with the metal types. In addition to the metal concentrations in the o

关键词： Magmatic hydrothermal deposits Fluid inclusions LA-ICP-MS Metal enrichment Mineralization mechanism

激光诱导火花点火和电火花点火着火过程的对比研究

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内燃机工程 2016年第4期37卷 113-118页

作者：麻剑严霁阳姚子澍郑旭许沧粟浙江大学动力机械及车辆工程研究所杭州310027 浙江大学城市学院杭州310015

应用高速纹影成像技术研究调Q Nd：YAG纳秒脉冲激光诱导火花点燃汽油/空气混合气的火核发展过程，并与传统电火花点火的火核发展过程相对比，详细阐述了激光诱导火花点火过程中有别于电火花点火过程的球形火核发展的三瓣结构火核的形成... 详细信息

应用高速纹影成像技术研究调Q Nd：YAG纳秒脉冲激光诱导火花点燃汽油/空气混合气的火核发展过程，并与传统电火花点火的火核发展过程相对比，详细阐述了激光诱导火花点火过程中有别于电火花点火过程的球形火核发展的三瓣结构火核的形成机理。进一步研究了0.1MPa、363K条件下，激光诱导火花、电火花点燃不同当量比下的汽油/空气混合气的着火概率。研究结果表明：激光诱导火花点火可以提高燃烧速度，并且能扩展稀燃极限，其在点燃当量比0.6（电火花点火稀燃极限）的稀混合气时，着火概率达65%-70%。

关键词：内燃机激光诱导火花点火电火花点火三瓣结构可燃界限

Trimetallic mesoporous PdCuRu for efficient formate electrosynthesis from polyethylene terephthalate recycling

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Science China Chemistry 2025年

作者： Yuting Li Huiqin yao Lizhi Sun shu Han Xiaoxiang Xu Guangyin Fan Ben Liu College of Chemistry and Materials Science Sichuan Normal University Key Laboratory of Green Chemistry and Technology of Ministry of Education College of Chemistry Sichuan University School of Basic Medical Sciences Ningxia Medical University Department of Otorhinolaryngology-Head and Neck Surgery Zhongnan Hospital of Wuhan University

Electrochemical recycling of waste polyethylene terephthalate（PET） plastics represents a green and sustainable route to produce valuable fuels and address serious environmental issues. Despite some encouraged achievements, their progress is still slower because of the lack of highly active and selective electrocatalysts. Here, we reported an efficient PET recycling route with trimetallic PdCuRu mesoporous nanospheres（MSs） as a high-performance electrocatalyst that achieved selective electrosynthesis of valuable formate from PET hydrolysate（PETH） electrooxidation. Penetrated metal mesopores and trimetallic compositions of PdCuRu MSs synergistically optimized electronic structures of Pd sites and changed chemisorption properties of intermediates, which disclosed a high formate Faradic efficiency of 97% and impressive yield rate of 0.49 mmol h-1cm-2in an alkaline solution. Meanwhile, this electrocatalyst held good electrocatalytic stability, retaining high formate Faradic efficiency and yield rate even being performed for 10 cycles, which highlighted its potential applications for practical PET recycling. Our study provides a powerful strategy for designing high-performance electrocatalysts toward selective electro-synthesis of valuable fuels from various waste plastics.

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Attention Eraser and Quantitative Measures for Automated Bone Age Assessment

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Computers, Materials & Continua 2025年第1期82卷 627-644页

作者： Liuqiang shu Lei Yu College of Computer and Information Science Chongqing Normal UniversityChongqing401331China

Bone age assessment(BAA)aims to determine whether a child’s growth and development are normal concerning their chronological *** predict bone age more accurately based on radiographs,and for the left-hand X-ray images of different races model can have better adaptability,we propose a neural network in parallel with the quantitative features from the left-hand bone measurements for *** this study,a lightweight feature extractor(LFE)is designed to obtain the featuremaps fromradiographs,and amodule called attention erasermodule(AEM)is proposed to capture the fine-grained ***,the dimensional information of the metacarpal parts in the radiographs is measured to enhance the model’s generalization capability across images fromdifferent *** is trained and validated on the RSNA,RHPE,and digital hand atlas datasets,which include images from various racial *** model achieves a mean absolute error(MAE)of 4.42 months on the RSNA dataset and 15.98 months on the RHPE *** to ResNet50,InceptionV3,and several state-of-the-art methods,our proposed method shows statistically significant improvements(p<0.05),with a reduction in MAE by 0.2±0.02 years across different racial ***,t-tests on the features also confirm the statistical significance of our approach(p<0.05).

关键词： Bone age assessment attention eraser quantitative feature metacarpal bones

Metastable seed-crystals: epitaxial growth of branched-array organic heterostructure nanowires

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Science China Chemistry 2025年

作者： Jin Feng Zhen-Yu Geng Ting-yao Song Ying-Xin Ma Chuan-Zeng Wang Wei Zhang Hong-Tao Lin Jin Zhou shu-Ping Zhuo shu-Hai Chen Xue-Dong Wang School of Chemistry and Chemical Engineering Shandong University of Technology Institute of Functional Nano & Soft Materials (FUNSOM) Jiangsu Key Laboratory for Carbon-Based Functional Materials & DevicesSoochow University College of Chemistry and Chemical Engineering Hunan Normal University

Tunable light–matter interactions are exhibited by organic low-dimensional crystals, making these crystals a promising platform for organic photonics. However, the precise synthesis of organic low-dimensional crystals remains challenging due to the stochastic nature of molecular nucleation processes. Herein, the directed nucleation process is driven by the introduction of metastable seed-crystals as the trunk, which ultimately leads to branched-array organic heterostructures. The successful formation of organic heterostructures with high-density branched arrays is attributed to the highest attachment energy (Eatt（023）=-104.25 kcal mol-1) of the exposed （023） crystal plane during the seed-crystal growth route. Significantly, these as-prepared heterostructures inherently have an ultralow lattice mismatch ratio η of 0.7%between trunk and branch, which contributes to the multi-channel photon transportation. Therefore, this work provides valuable insights into a versatile synthetic strategy for accessing low-dimensional heterostructures for integrated optoelectronics.

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教学反思中教师思维品质的局限与提升

教学与管理 2025年第2期 1-5页

作者：刘子姝首都师范大学教育学院北京100048

有关教学反思的现状与探讨一直是教育实践场域中教师关注的热点问题。其中,教师的思维品质决定了教师教学反思的阈值。教学反思应指向教师的思维品质。然而在实践中,教学反思存在游离于价值性目标、忠实于知能积累、模糊意义性生成等现... 详细信息

有关教学反思的现状与探讨一直是教育实践场域中教师关注的热点问题。其中,教师的思维品质决定了教师教学反思的阈值。教学反思应指向教师的思维品质。然而在实践中,教学反思存在游离于价值性目标、忠实于知能积累、模糊意义性生成等现实境况。为此,通过关注教师反思来剖析其思维品质在深刻性、批判性、系统性和创造性等方面的现实境况,挖掘思维品质背后教师教育教学思维的发生与发展,从而为促进教师思维品质提升提出改善策略:明确反思目标的价值性,坚持育人导向;关注反思内容的教育性,促进思维发生;超越反思结果的符号性,构建个性化意义。

关键词：思维品质教学反思反思要素