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Dealuminated Hβ zeolite for selective conversion of fructose to furfural and formic acid

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Green Energy & Environment 2024年第2期9卷 311-320页

作者： Rui Li Qixuan Lin Junli Ren xiaobao Yang Yingxiong Wang Lingzhao Kong State Key Laboratory of Pulp and Paper Engineering School of Light Industry and EngineeringSouth China University of TechnologyGuangzhou510640China Institute of Coal Chemistry Chinese Academy of Sciences27 South Taoyuan RoadTaiyuan030001China CAS Key Laboratory of Low-Carbon Conversion Science and Engineering Shanghai Advanced Research InstituteChinese Academy of SciencesShanghai201210China School of Environmental Science and Technology Suzhou University of Science and Technology Suzhou Jiangsu215009China

The fructose-to-furfural transformation is facing major challenges in the selectivity and high efficiency. Herein, we have developed a simple and effective approach for the selective conversion of fructose to furfural using Hβ zeolite modified by organic acids for dealuminization to regulate its textural and acidic properties. It was found that citric acid-dealuminized Hβ zeolite possessed high specific surface areas, wide channels and high Brønsted acid amount, which facilitated the selective conversion of fructose to furfural with a maximum yield of 76.2% at433 K for 1 h in the γ-butyrolactone(GBL)-H_(2)O system, as well as the concomitant formation of 83.0% formic acid. The^(13)C-isotope labelling experiments and the mechanism revealed that the selective cleavage of C1–C2 or C5–C6 bond on fructose was firstly occurred to form pentose or C5 intermediate by weak Brønsted acid, which was then dehydrated to furfural by strong Brønsted acid. Also this dealuminized Hβ catalyst showed the great recycling performance and was active for the conversion of glucose and mannose.

关键词： Fructose Dealuminated-Hb zeolite Selective conversion Furfural

Molecular Dynamics Simulations of Displacement Cascade in Ni-Based Concentrated Solid Solution Alloys

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Acta Mechanica Solida Sinica 2024年第1期37卷 82-89页

作者： Chaoquan Zhao Rongxuan Xie Chuanlong Xu xiaobao Tian Qingyuan Wang Wentao Jiang Haidong Fan Department of Mechanics Sichuan UniversityChengdu 610065China

Single-phase concentrated solid solution alloys(SP-CSAs),including high-entropy alloys,have received extensive attention due to their excellent irradiation *** this work,displacement cascade simulations are conducted using the molecular dynamics method to study the evolution of defects in Ni-based *** with pure Ni,the NiCr,NiCo,and NiCu alloys exhibit a larger number of Frankel pairs(FPs)in the thermal peak stage,but a smaller number of surviving ***,the NiFe alloy displays the opposite *** explain these different observations for NiFe and other alloys,the formation energy and migration energy of interstitials/vacancies are *** the NiFe alloy,both the formation energy and migration energy barrier are *** the other hand,in NiCr and other alloys,the formation energy of interstitials/vacancies is lower,as is the migration energy barrier of *** energy analysis agrees well with previous *** present work provides new insights into the mechanism behind the irradiation resistance of binary Ni-based SP-CSAs.

关键词： Molecular dynamics simulation Displacement cascade Point defect Ni-based concentrated solid solution alloys

Multi-field Coupled Inverse Hall–Petch Relations for Ferroelectric Nanocrystals

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Acta Mechanica Solida Sinica 2024年第1期37卷 139-147页

作者： Xiaodong Zhang Wei Yan Xuhui Lou Yujun Chen Zhihong Zhou Qingyuan Wang Lianhua Ma xiaobao Tian Non-Destructive Testing Laboratory School of Quality and Technical SupervisionHebei UniversityBaoding 071002China AVIC Huiyang Aviation Propeller Co. LtdBaoding 071051China Department of Mechanics and Engineering Sichuan UniversityChengdu 610065China Yibin Institute of Industrial Technology Sichuan University Yibin ParkYibin 644000China Research Institute of Interdisciplinary Sciences(RISE) Dongguan University of TechnologyDongguan 523808China School of Materials Science and Engineering Dongguan University of TechnologyDongguan 523808China

Tailoring grain size can improve the strength of polycrystals by regulating the proportion of grains to grain boundaries and the interaction *** the grain size decreases to the nanoscale,the deformation mechanism in polycrystals shifts from being primarily mediated by dislocations to deformation occurring within the grains and grain ***,the mechanism responsible for fine-grain strengthening in ferroelectric materials remains unclear,primarily due to the complex multi-field coupling effect arising from spontaneous *** molecular dynamics simulations,we investigate the strengthening mechanism of barium titanate(BaTiO3),with extremely fine-grain *** material exhibits an inverse Hall–Petch relationship between grain size and strength,rooting in the inhomogeneous concentration of atomic strain and grain ***,we present a theoretical model to predict the transition from the inverse Hall–Petch stage to the Hall–Petch stage based on strength variations with size,which aligns well with the simulation *** has been found that the piezoelectric properties of the BaTiO3 are affected by polarization domain switching at various grain *** study enhances our understanding of the atomic-scale mechanisms that contribute to the performance evolution of fine-grain nano-ferroelectric *** also provides valuable insights into the design of extremely small-scale ferroelectric components.

关键词： Ferroelectrics Multi-field coupling Molecular dynamics Fine-grain reinforcement Inverse Hall-Petch effect

Entanglement dynamics in κ-deformed spacetime

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Science China(Physics,Mechanics & Astronomy) 2024年

作者： xiaobao Liu Zehua Tian Jiliang Jing Department of Physics and Electrical Engineering Liupanshui Normal University School of Physics Hangzhou Normal University CAS Key Laboratory of Microscale Magnetic Resonance and School of Physical Sciences University of Science and Technology of China Department of Physics Key Laboratory of Low Dimensional Quantum Structures and Quantum Control of Ministry of EducationSynergetic Innovation Center for Quantum Effects and Applications Hunan Normal University

We treat two identical and mutually independent two-level atoms that are coupled to a quantum field as an open quantum *** master equation that governs their evolution is derived by tracing over the degree of freedom of the field. With this, we compare the entanglement dynamics of the two atoms moving with different trajectories in κ-deformed and Minkowski ***, when the environment-induced interatomic interaction does not exist, the entanglement dynamics of two static atoms in κ-deformed spacetime are reduced to that in Minkowski spacetime in the case that the spacetime deformation parameter κ is sufficiently large as theoretically predicted. However, if the atoms undergo relativistic motion, regardless of whether inertial or non-inertial, their entanglement dynamics in κ-deformed spacetime behave differently from that in Minkowski spacetime even when κ is large. We investigate various types of entanglement behavior, such as decay and generation, and discuss how different relativistic motions, such as uniform motion in a straight line and circular motion, amplify the differences in the entanglement dynamics between the κ-deformed and Minkowski spacetime cases. In addition, when the environment-induced interatomic interaction is considered, we find that it may also enhance the differences in the entanglement dynamics between these two ***, in principle, one can tell whether she/he is in κ-deformed or Minkowski spacetime by checking the entanglement behavior between two atoms in certain circumstances.

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Efficient Photolytic Halogenation and Oxidation of Unactivated Alkyl sp^(3) C—H Bonds with Iodine(III)

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Chinese Journal of Chemistry 2024年第5期42卷 505-510页

作者： Hao Jia Nan Li Chunmei Tang Yajuan Wang Yonghao Xi Rongbao Liao Wei Xu Fufang Wu xiaobao Shen Hongbin Zhai Biomass Oligosaccharides Engineering Technology Research Center of Anhui Province Engineering Research Center of Biomass Conversion and Pollution Prevention of Anhui Educational InstitutionsFuyang Normal UniversityFuyangAnhui236037 China Institute of Marine Biomedicine Shenzhen PolytechnicShenzhenGuangdong518055 China State Key Laboratory of Chemical Oncogenomics Shenzhen Engineering Laboratory of Nano Drug Slow-ReleasePeking University Shenzhen Graduate SchoolShenzhenGuangdong518055 China

A metal-free,green,and sustainable functionalization of unactivated alkyl sp^(3) C—H bonds is reported using iodine(III)as a feasible dehydrogenation agent under visible light or KBr,and alkyl chlorides,bromides,alcohols,and ketones could be constructed by addition of different coupling *** and safe iodobenzene diacetate was used to form a radical to activate the alkyl sp^(3) C—H bond in a highly efficient manner,which can construct different alkylation products by adding corresponding coupling reagents.

关键词： Alkyl sp^(3)C—H bonds Chlorination Bromination Oxidation Iodine(III) C—H activation Radical Photocatalysis

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社区户内燃气泄漏动态预警模型

中国安全科学学报 2022年第3期32卷 90-97页

作者：李超邓小宝史运涛孙德辉焦彦宗北方工业大学电气与控制工程学院北京100144 北方工业大学现场总线技术及自动化北京市重点实验室北京100144

为提升社区户内燃气泄漏动态预警的能力,构建一种社区户内燃气泄漏动态预警模型。首先,利用无线传感器网络采集社区户内燃气数据,通过智能网关实现数据上云的功能;其次,在云平台中利用模糊控制算法优化随机森林算法的输入,减少重要度较... 详细信息

为提升社区户内燃气泄漏动态预警的能力,构建一种社区户内燃气泄漏动态预警模型。首先,利用无线传感器网络采集社区户内燃气数据,通过智能网关实现数据上云的功能;其次,在云平台中利用模糊控制算法优化随机森林算法的输入,减少重要度较低特征的干扰,并将优化后的数据作为随机森林算法的输入,以泄漏等级作为输出,建立模糊-随机森林模型;然后,开发可视化模块,以显示社区户内燃气泄漏的等级;最后,根据北京某社区燃气历史数据,在实验室条件下进行仿真模拟,验证该模型的有效性。结果表明:该模型可有效提升社区户内燃气泄漏的在线监测和动态预警的能力,与其他算法相比,模糊-随机森林算法在发现早期微小泄漏方面表现更优。

关键词：社区户内燃气泄漏动态预警在线监测模糊控制算法随机森林算法

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基于点云迁移的人体点云位置及颜色补全

信号处理 2022年第9期38卷 1777-1785页

作者：安平陈星宇邓小宝陈亦雷上海先进通信与数据科学研究院新型显示技术及应用集成教育部重点实验室上海大学通信与信息工程学院上海200444

由于三维扫描设备获取的点云存在目标遮挡、设备视角等问题,致使点云有所缺失。点云补全是为下游任务进行点云预处理的重要工作。然而现有的点云补全工作集中在对简单物体的补全上,缺乏对较复杂人体点云补全的研究。为将点云补全任务引... 详细信息

由于三维扫描设备获取的点云存在目标遮挡、设备视角等问题,致使点云有所缺失。点云补全是为下游任务进行点云预处理的重要工作。然而现有的点云补全工作集中在对简单物体的补全上,缺乏对较复杂人体点云补全的研究。为将点云补全任务引入下游人体重建相关任务中,本文提出了一种由粗到精的人体点云预测方法,对人体位置及颜色缺失信息补全。通过创建具有精细服饰纹理的人体点云数据集,采用点云迁移的网络结构,充分利用点云全局粗糙信息,结合多层网络预测完整点云,优化了上采样方案;然后,在上采样后的点云上进行了颜色补全,通过部分点云颜色信息进行特征值扩散和提取;最后,通过一个多层感知机进行颜色预测。在人体数据集上的实验结果表明,该方法相比现有主流方法不仅在客观指标上具有更好的表现,主观质量上也能保证获得更加完整、边缘清晰的点云。

关键词：点云形状补全人体重建

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计及煤耗率的尖峰电价优化模型及灵敏度分析

系统工程理论与实践 2024年第7期44卷 2260-2272页

作者：喻小宝董真余郑丹丹邓思维上海电力大学经济与管理学院上海200090 中国电建集团贵阳勘测设计研究院有限公司规划研究院贵阳550081

尖峰电价(critical peak pricing, CPP)是通过需求侧管理实现发电侧节能减排的重要手段.现有主流电价优化模型忽略了CPP对发电供给侧的影响,对尖峰日与非尖峰日时终端用电行为的差异性分析也存在不足.本文通过研究CPP对供电侧机组运行... 详细信息

尖峰电价(critical peak pricing, CPP)是通过需求侧管理实现发电侧节能减排的重要手段.现有主流电价优化模型忽略了CPP对发电供给侧的影响,对尖峰日与非尖峰日时终端用电行为的差异性分析也存在不足.本文通过研究CPP对供电侧机组运行的影响机制,挖掘终端用电行为的差异性,设计了针对不同时期的用电需求响应模型,综合考虑发电侧供电煤耗和终端用户满意度,构建CPP多目标优化模型,采用NSGA-Ⅱ遗传算法进行求解.基于3类场景分析用户需求响应模型参数的取值、终端满意度约束、电价费率限制三类指标对CPP定价、负荷改善情况以及机组煤耗减少量的灵敏性,验证了模型的有效性.结果显示:所提电价优化模型效果较好,并且用户响应斜率、终端满意度、电价费率限制对CPP定价、负荷改善情况以及机组煤耗减少量的影响较大.

关键词：尖峰电价供电煤耗电价费率灵敏度分析

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平衡时间洞察力与心理健康的关系:情绪调节策略的中介作用

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心理科学 2024年第3期47卷 562-569页

作者：李小保吕厚超西南大学心理学部时间心理学研究中心重庆400715

基于1432名被试(M=29.04岁,SD=14.38岁),本研究旨在探究平衡时间洞察力与心理健康的关系,并检验情绪调节策略的中介效应。结果发现:(1)平衡时间洞察力与生活满意度、积极情感正相关,与消极情绪、焦虑负相关。(2)平衡时间洞察力与认知重... 详细信息

基于1432名被试(M=29.04岁,SD=14.38岁),本研究旨在探究平衡时间洞察力与心理健康的关系,并检验情绪调节策略的中介效应。结果发现:(1)平衡时间洞察力与生活满意度、积极情感正相关,与消极情绪、焦虑负相关。(2)平衡时间洞察力与认知重评正相关,与表达抑制负相关。认知重评与生活满意度、积极情绪呈正相关,与焦虑、消极情绪呈负相关;表达抑制与消极情绪、焦虑呈正相关。(3)认知重评、表达抑制在平衡时间洞察力与总体心理健康之间起部分中介作用。研究结果强调了平衡时间洞察力对人们的情绪调节和心理健康的重要意义,并给出了培养和构建平衡时间洞察力的建议。

关键词：时间洞察力平衡时间洞察力心理健康情绪调节策略