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Journal of Energy Chemistry 2021年第11期30卷 653-659,I0016页

作者： Feifei Dong Zhenghui Gao Bingkai Zhang Lu Li ziqi kong Zilin Ma Meng Ni Zhan Lin Guangzhou Key Laboratory of Clean Transportation Energy Chemistry School of Chemical Engineering and Light IndustryGuangdong University of TechnologyGuangzhou Higher Education Mega CenterGuangzhou 510006GuangdongChina Building Energy Research Group Department of Building and Real EstateThe Hong Kong Polytechnic UniversityHung HomKowloonHong Kong 999077China

In response to the shortcomings of cobalt-rich cathodes, iron-based perovskite oxides appear as promising alternatives for solid oxide fuel cells (SOFCs). However, their inferior electrochemical performance at reduced temperatures (<700 ℃) becomes a major bottleneck for future progress. Here, a novel cobalt-free perovskite Ba_(0.75)Sr_(0.25)Fe_(0.875)Ga_(0.125)O_(3−δ) (BSFG) is developed as an efficient oxygen reduction electrode for SOFCs, featuring cubic-symmetry structure, large oxygen vacancy concentration and fast oxygen transport. Benefiting from these merits, cells incorporated with BSFG achieve exceptionally high electrochemical performance, as evidenced by a low polarization area-specific resistance of 0.074 Ω cm^(2) and a high peak power density of 1145 mW cm^(−2) at 600 ℃. Meanwhile, a robust short-term performance stability of BSFG cathode can be ascribed to the stable crystalline structure and favorable thermal expansion behavior. First-principles computations are also conducted to understanding the superior activity and durability toward oxygen reduction reaction. These pave the way for rationally developing highly active and robust cobalt-free perovskite-type cathode materials for reduced-temperature SOFCs.

关键词： Solid oxide fuel cell Cathode Perovskite Oxygen reduction reaction Cobalt-free

Mechanisms of isomerization and hydration reactions of typicalβ-diketone at the air-droplet interface

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Journal of Environmental Sciences 2024年第7期141卷 225-234页

作者： Yuemeng Ji Weiyong Luo Qiuju Shi Xiaohui Ma ziqi Wu Weina Zhang Yanpeng Gao Taicheng An Guangdong-Hong kong-Macao Joint Laboratory for Contaminants Exposure and Health Guangdong Key Laboratory of Environmental Catalysis and Health Risk ControlInstitute Environmental Health and Pollution ControlGuangdong University of TechnologyGuangzhou 510006China Guangzhou Key Laboratory of Environmental Catalysis and Pollution Control Key Laboratory for City Cluster Environmental Safety and Green Development of the Ministry of EducationSchool of Environmental Science and EngineeringGuangdong University of TechnologyGuangzhou 510006China

Acetylacetone(AcAc)is a typical class ofβ-diketones with broad industrial applications due to the property of the keto-enol isomers,but its isomerization and chemical reactions at the air-droplet interface are still ***,using combined molecular dynamics and quantum chemistry methods,the heterogeneous chemistry of AcAc at the air-droplet interface was investigated,including the attraction of AcAc isomers by the droplets,the distribution of isomers at the air-droplet interface,and the hydration reactions of isomers at the air-droplet *** results reveal that the preferential orientation of two AcAc isomers(keto-and enol-AcAc)to accumulate and accommodate at the acidic air-droplet *** isomerization of two AcAc isomers at the acidic air-droplet interface is more favorable than that at the neutral air-droplet interface because the“water bridge”structure is destroyed by H_(3)O^(+),especially for the isomerization from keto-Ac Ac to *** the acidic air-droplet interface,the carbonyl or hydroxyl O-atoms of two AcAc isomers display an energetical preference to ***-diol is the dominant products to accumulate at the air-droplet interface,and excessive keto-diol can enter the droplet interior to engage in the *** photooxidation reaction of AcAc will increase the acidity of the air-droplet interface,which indirectly facilitate the uptake and formation of more *** results provide an insight into the heterogeneous chemistry ofβ-diketones and their influence on the environment.

关键词： Acetylacetone Air-droplet interface Theoretical simulation Isomerization Hydration reaction mechanism

Synthesis,Structures,and Chiroptical Properties of NBN-Doped Helicenes with Boron Atoms in the Inner Rims

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Precision Chemistry 2024年第1期2卷 28-39页

作者： Weiwen Zhuang Yujian Liu ziqi Deng Yu Guo Philip C.Y.Chow David Lee Phillips Wei Jiang Zhaohui Wang Junzhi Liu State Key Laboratory of Synthetic Chemistry HKU-CAS Joint Laboratory on New Materials and Department of ChemistryThe University of Hong KongPokfulamHong KongChina Key Laboratory of Organic Optoelectronics and Molecular Engineering Department of ChemistryTsinghua UniversityBeijing 100084China Department of Mechanical Engineering The University of Hong KongPokfulamHong KongChina

The precise synthesis of helicenes with topologically defined length and specific heteroatomic perturbation in the screw-like conjugated skeletons plays an emerging role in the manipulation of chiral ***,selective,and programmable routes to helicenes or heterohelicenes are highly desirable yet challenging for structure-chiroptical property relationship ***,we report the synthesis and characterization of NBN-doped helicenes with boron atoms in the inner rims,enabled by the highly regioselective one-pot borylation of rationally designed precursors with,namely,fold-in or pan-out *** incorporation of nonbonded boron and nitrogen atoms resulted in narrow-band emission and improved optical properties for the single-stranded carbon *** addition,numbers and arrangement modes of fused six-membered rings have distinct effects on configurational stability and chiroptical properties,revealing that BN-[6]H with strong circular dichroism is a promising candidate for chiral *** combination of experimental and theoretical studies on these helical structures might provide insights into the design of helically chiral small-molecule-based sensors or emitters.

关键词： Nitrogen-boron Helicenes Borylation Chiroptical properties Narrow-band emission

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XLPE裂解产气的分子动力学模拟

工程塑料应用 2024年第6期52卷 155-163页

作者：黄友聪郑钟楠林梓圻张莹袁豪孔佳民周凯国网福建省电力有限公司电力科学研究院福州350000 四川大学电气工程学院成都610065

交联聚乙烯(XLPE)电缆是城市输配电网络中的重要设备,对XLPE绝缘材料裂解机理的深入理解是提出有效故障评估和诊断方法的基本前提,近年来。通过气体产物对电缆进行状态诊断的思想广受关注,然而,现有研究仍未深入阐释影响XLPE绝缘的产气... 详细信息

交联聚乙烯(XLPE)电缆是城市输配电网络中的重要设备,对XLPE绝缘材料裂解机理的深入理解是提出有效故障评估和诊断方法的基本前提,近年来。通过气体产物对电缆进行状态诊断的思想广受关注,然而,现有研究仍未深入阐释影响XLPE绝缘的产气路径和机理。鉴于此,基于分子动力学模拟方法,从原子和自由基层面揭示了XLPE裂解及产气机理。首先基于蒙特卡洛法构建聚乙烯分子的初始几何模型。通过基于距离概率准则的聚乙烯交联算法,建立了具有高度化学合理性和现实物理意义的XLPE分子动力学几何模型。随后基于ReaxFF反应力场进行了分子动力学计算,并通过粒子追踪建立了XLPE裂解过程中特征气体产物生成的自由基链式反应路径。结果表明,氢气生成的自由基链式反应包含两步且为可逆反应;烃类气体分子及碳氧化物分子生成自由基链式反应均始于XLPE分子链C—C键断裂生成亚甲基端基,具体生成的产物类型由氧气和氢自由基的浓度决定。上述研究为理解XLPE电缆系统中的产气现象和从原子层面揭示XLPE固体电介质劣化及产气机理方面提供了借鉴。

关键词：分子动力学交联聚乙烯材料产气自由基反应 ReaxFF力场

消费符号下城市新旧电影院空间生产及功能演化——以西安市为例

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经济地理 2021年第1期41卷 87-94页

作者：李修远杨晓俊孔资淇雷蕾西安外国语大学旅游学院·人文地理研究所中国陕西西安710128 西安外国语大学城乡空间融合发展创新团队中国陕西西安710128

基于消费地理学视角,运用模糊综合评价方法,从消费符号角度对西安市以影院为代表的城市消费空间进行研究,旨在揭示城市文化产业的发展规律。结果表明:消费社会中居民消费趋向符号化消费,物质消费过渡精神消费。旧式影院空间具有开放性,... 详细信息

基于消费地理学视角,运用模糊综合评价方法,从消费符号角度对西安市以影院为代表的城市消费空间进行研究,旨在揭示城市文化产业的发展规律。结果表明:消费社会中居民消费趋向符号化消费,物质消费过渡精神消费。旧式影院空间具有开放性,公益性和科普性的社会效益明显,新式影院放映空间呈现封闭特征,趋利化与商业化的经济效益显著。影院分布由单体建筑向依附商业综合体转变,空间分布呈现不均衡性。不同时期影院空间与功能的变化,表现了消费社会中符号消费的空间置换。文章可为城市文化空间和文化产业布局提供参考。

关键词：消费文化消费符号电影院模糊综合评价文化价值商业性公益性

2022年南黄海绿潮分布与浮游生物群落关系初探

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海洋科学 2024年第3期48卷 26-41页

作者：唐紫琦宋敏杰王馨孔凡洲耿慧霞颜天中国科学院海洋生态与环境科学重点实验室中国科学院海洋研究所山东青岛266071 中国科学院大学北京100049

本文以2022年南黄海(119°E~122.5°E,34.5°N~37°N)表层海水浮游生物为对象,利用高通量测序技术分析绿潮期间浮游生物群落结构特征,同时对环境要素进行调查,综合分析环境与浮游生物分布之间的潜在关联,为掌握南黄海绿潮的生态效应提... 详细信息

本文以2022年南黄海(119°E~122.5°E,34.5°N~37°N)表层海水浮游生物为对象,利用高通量测序技术分析绿潮期间浮游生物群落结构特征,同时对环境要素进行调查,综合分析环境与浮游生物分布之间的潜在关联,为掌握南黄海绿潮的生态效应提供依据。结果表明,2022年7月上旬调查期间南黄海绿潮浒苔生物量湿重估计值为7.24×104吨,分布特征为以山东近岸以及海州湾附近为主要堆积处,浒苔生物量、浮游植物以及浮游动物与溶解性无机磷酸盐均有着显著的正相关性。浒苔覆盖区域中,浮游植物和浮游动物都有着较高的丰富度,甲藻和桡足类为主要优势种,属水平下包括:新角藻、未分类到属的共甲藻、薮枝螅水母、尖头溞等。与无浒苔覆盖的区域相比,该区域优势种相对单一,导致次生灾害发生的可能性大。浮游细菌群落调查中发现脱硫单胞菌纲和优势种γ-变形菌纲都与浒苔生物量有着紧密的联系,其中脱硫单胞菌与浒苔生物量呈显著性正相关,γ-变形菌纲与浒苔生物量呈显著性负相关。相关性分析表明,浮游细菌多样性与环境中总溶解性氮、磷以及溶解性有机氮呈显著性相关,结合浒苔与环境因子相关性分析,浒苔绿潮的发生可以为某些浮游细菌提供生长所需的营养物质。共线性网络分析表明,在绿潮发生的浒苔覆盖区域,浮游生物丰富度高且关系紧密复杂,因此浒苔绿潮对浮游生物的群落结构以及丰富度有潜在的影响。

关键词：浮游生物绿潮南黄海

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从信号到知识——基于人工智能的医学影像裸数据诊断价值初探

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Engineering 2024年第3期34卷 60-69页

作者： Bingxi He Yu Guo Yongbei Zhu Lixia Tong Boyu kong Kun Wang Caixia Sun Hailin Li Feng Huang Liwei Wu Meng Wang Fanyang Meng Le Dou Kai Sun Tong Tong Zhenyu Liu ziqi Wei Wei Mu Shuo Wang Zhenchao Tang Shuaitong Zhang Jingwei Wei Lizhi Shao Mengjie Fang Juntao Li Shouping Zhu Lili Zhou Shuo Wang Di Dong Huimao Zhang Jie Tian Beijing Advanced Innovation Center for Big Data-Based Precision Medicine School of Engineering MedicineBeihang UniversityBeijing 100191China Key Laboratory of Big Data-Based Precision Medicine Beihang UniversityMinistry of Industry and Information TechnologyBeijing 100191China CAS Key Laboratory of Molecular Imaging Institute of AutomationChinese Academy of SciencesBeijing 100190China Department of Radiology The First Hospital of Jilin UniversityChangchun 130021China Neusoft Medical Systems Co.Ltd. Shenyang 110167China Neusoft Research of Intelligent Healthcare Technology Co.Ltd. Shenyang 110167China School of Life Science and Technology Xidian UniversityXi’an 710126China Engineering Research Center of Molecular and Neuro Imaging Ministry of EducationXi’an 710126China School of Artificial Intelligence University of Chinese Academy of SciencesBeijing 100049China

Encouraging and astonishing developments have recently been achieved in image-based diagnostic *** medical care and imaging technology are becoming increasingly ***,the current diagnosis pattern of signal to image to knowledge inevitably leads to information distortion and noise introduction in the procedure of image reconstruction(from signal to image).Artificial intelligence(AI)technologies that can mine knowledge from vast amounts of data offer opportunities to disrupt established *** this prospective study,for the first time,we develop an AI-based signal-toknowledge diagnostic scheme for lung nodule classification directly from the computed tomography(CT)raw data(the signal).We find that the raw data achieves almost comparable performance with CT,indicating that it is possible to diagnose diseases without reconstructing ***,the incorporation of raw data through three common convolutional network structures greatly improves the performance of the CT models in all cohorts(with a gain ranging from 0.01 to 0.12),demonstrating that raw data contains diagnostic information that CT does not *** results break new ground and demonstrate the potential for direct signal-to-knowledge domain analysis.

关键词： Computed tomography Diagnosis Deep learning Lung cancer Raw data

河套平原表层土壤中天然有机氯代物的空间分布特征

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安全与环境工程 2024年第4期31卷 181-188,235页

作者：孔瑶瑶陈柳竹巨凡凡陈占强陈钰彭子琪中国地质大学(武汉)环境学院湖北武汉430078

为查明河套平原表层土壤中天然有机氯代物(Clorg)的空间分布特征及影响因素,在河套平原采集55个表层土壤(0~20 cm)样品,对其理化性质(质地、pH值、总有机碳含量)及不同形态氯元素含量进行分析,并通过采用描述性统计、相关性分析等方法... 详细信息

为查明河套平原表层土壤中天然有机氯代物(Clorg)的空间分布特征及影响因素,在河套平原采集55个表层土壤(0~20 cm)样品,对其理化性质(质地、pH值、总有机碳含量)及不同形态氯元素含量进行分析,并通过采用描述性统计、相关性分析等方法对分析数据进行处理。结果表明:土壤中天然Clorg的含量在18.84~182.75 mg/kg之间,其平均含量为56.06 mg/kg,占总氯(Cltot)含量的1.74%~92.81%;空间上,河套平原西部黄河冲积扇平原表层土壤中天然Clorg含量整体高于东部黄河泛滥冲积平原表层土壤;土壤中天然Clorg的含量与氯离子(Cl-)含量呈正相关关系、与pH值呈负相关关系、与总有机碳(TOC)含量之间相关性不显著;土壤质地明显影响土壤中天然Clorg的含量,其中砂质壤土中天然Clorg的平均含量最高;天然Clorg在研究区表层土壤中普遍存在,其空间分布格局是Cl-、TOC、pH值、土壤质地等多因素共同作用的结果,较高的Cl-含量、较低的pH值以及砂质壤土更有利于土壤中天然Clorg的积累,在较高盐度水平下,TOC含量对表层土壤中天然Clorg的积累无显著影响。

关键词：天然有机氯代物空间分布特征表层土壤河套平原

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某厢式车行驶时车内闷音成因分析与验证

时代汽车 2024年第11期 139-141页

作者：张明旭孔喜磊马富豪张紫琪杨竣博郑州日产汽车有限公司河南郑州450016 桂林电子科技大学广西桂林541004

本文针对某厢式车行驶至某一车速时,车内出现的闷音问题进行成因分析及验证。通过分析该厢式车动力传动系统振动加速度以及车内闷音强度的测试数据,确定闷音产生的具体原因,并通过相关试验对分析结果的准确性和可靠性进行验证。经分析,... 详细信息

本文针对某厢式车行驶至某一车速时,车内出现的闷音问题进行成因分析及验证。通过分析该厢式车动力传动系统振动加速度以及车内闷音强度的测试数据,确定闷音产生的具体原因,并通过相关试验对分析结果的准确性和可靠性进行验证。经分析,该厢式车内闷音的成因是动力传动系统与整车发生共振,前主减速器某悬置隔振效果较差,导致车架端存在较高的振动加速度,再经由各零部件传递至车内,诱发车内严重的闷音。并通过施加相应的约束进行相应的试验,对上述结论进行验证。

关键词：厢式车闷音动力传动系统主减速器

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数字技术跃迁与企业全要素生产率——从自动化到智能化的比较分析

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经济评论 2024年第4期 73-89页

作者：刘征驰高翔宇陈文武伍子祺湖南大学经济与贸易学院 410079 北京大学长沙计算与数字经济研究院 410205 香港中文大学深圳数据经济研究院 410079 南方科技大学理学院 518055

本文在利用文本分析法从微观企业层面测度自动化、智能化水平的基础上,理论分析并实证检验了自动化、智能化对企业全要素生产率的影响及其作用机制。研究表明,自动化、智能化均能显著提升企业全要素生产率,但智能化的提升作用相对更大... 详细信息

本文在利用文本分析法从微观企业层面测度自动化、智能化水平的基础上,理论分析并实证检验了自动化、智能化对企业全要素生产率的影响及其作用机制。研究表明,自动化、智能化均能显著提升企业全要素生产率,但智能化的提升作用相对更大。自动化主要通过替代效应和“干中学”效应推动企业全要素生产率提高,智能化主要通过替代效应、互补效应、“干中学”效应与“用中学”效应推动企业全要素生产率提高。自动化、智能化在国有企业与非国有企业,以及在不同行业的企业中,对全要素生产率的作用具有差异性。本研究为新时代中国利用自动化向智能化的技术跃迁,加快形成新质生产力,推动经济高质量发展提供了理论参考与经验证据。

关键词：自动化智能化技术跃迁全要素生产率新质生产力