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Enhanced cyclic stability of partially disordered spinel cathodes through direct fluorination with gaseous fluorine

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Rare Metals 2024年第4期43卷 1635-1646页

作者： Yong-nian Ma Ling-Chen Kong shao-Shan Chen Yong Wang Li-Dong Sun Cong Peng Meng-Meng Qin Yu Li Wei Feng Tianjin Key Laboratory of Composite and Functional Materials School of Materials Science and EngineeringTianjin University Institute of Advanced Technology and Equipment Beijing University of Chemical Technology

Spinel-type cathodes are considered an optimal substitute for conventional layered oxide cathodes owing to their use of inexpensive and earth-abundant manganese as the redox-active element.Moreover,the introduction of cation disorder can effectively suppress the detrimental two-phase reaction to realize high capacities in a wide voltage range.However,the continuous capacity decay during cycles has hindered the widespread application of these cathode materials.Inorganic fluorides exhibit excellent electrochemical stability at high voltage;therefore,in this study,the direct F2 gas reaction with a partially disordered spinel cathode(Li1.6Mn1.6O3.7F0.3,LMOF1.6) was initially applied to investigate the impacts of fluorination on the surface structure and electrochemical performances.The inorganic fluorinated layer,mainly containing LiF,was distributed uniformly on the surface of LMOF1.6nanoparticles after fluorination for an appropriate time without the turbulence caused by the valency of manganese cation,which improved the capacity retention and rate capability by the suppression of structural damage,parasitic reaction,and cation dissolution.The LMOF1.6cathode fluorinated for 0.5 h exhibited a capacity of283.6 mAh·g-1at 50 mA·g-1and an enhanced capacity retention of 29.6% after 50 cycles in the voltage range of1.5-4.8 V,as compared to the pristine LMOF1.6 with only27.9% capacity retention.

关键词： Spinel-type cathodes Direct fluorination Capacity retention ability High rate capability

Potential and application of abortive transcripts as a novel molecular marker of cancers

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World Journal of Experimental Medicine 2024年第2期14卷 53-61页

作者： Tian-Miao Zhang Xiao-nian Zhu shao-Wei Qin Xue-Feng Guo Xue-Kun Xing Li-Feng Zhao Sheng-Kui Tan Guangxi Key Laboratory of Environmental Exposomics and Entire Lifecycle Health Guilin Medical UniversityGuilin 541199Guangxi Zhuang Autonomous RegionChina School of Leisure and Health Guilin Tourism UniversityGuilin 541006Guangxi Zhuang Autonomous RegionChina

Abortive transcript(AT)is a 2-19 nt long non-coding RNA that is produced in the abortive initiation stage.Abortive initiation was found to be closely related to RNA polymerase through in vitro experiments.Therefore,the distribution of AT length and the scale of abortive initiation are correlated to the promoter,discriminator,and transcription initiation sequence,and can be affected by transcription elongation factors.AT plays an important role in the occurrence and development of various diseases.Here we summarize the discovery of AT,the factors responsible for AT formation,the detection methods and biological functions of AT,to provide new clues for finding potential targets in the early diagnosis and treatment of cancers.

关键词： Abortive transcript Abortive initiation RNA polymerase Transcription Tumor marker

Enhanced photothermal dehydration of methanol over W_(18)O_(49)/Au/SAPO-34 catalysts with broadened light absorption

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Rare Metals 2024年第3期43卷 1139-1152页

作者： Ya-Qin Tang Meng-Xia Yan Chang-Qian Lu shao-Yuan Li Kui-Xian Wei Tao Qu Wen-HuiMa Yong-nian Dai Kong-Zhai Li Da-Jun Luo Xue-Liang Zhang Yi-Ke Liu Faculty of Metallurgical and Energy Engineering Kunming University of Science and TechnologyKunming650093China School of Materials and Energy Engineering Guizhou Institute of TechnologyGuiyang550003China

Methanol-to-olefins(MTO)process is one of the most critical pathways to produce low carbon olefins.Typically,the reaction is driven by thermal catalysis,which inevitably needs to consume large amounts of fossil fuel.Developing a new technique to substitute for the fuel burning is urgent for MTO process to improve the industry prospects and sustainability.Herein,we report a novel W_(18)O_(49)/Au/SAPO-34(W/Au/S),a multifunctional photothermal catalyst for the MTO reaction.A high methanol conversion was achieved under xenonum(Xe)lamp irradiation,yielding methyl ether(ME)and ethylene as the main products.The optimized W/Au/S catalysts showed ethylene yield as high as 250μmol in 60 min,which was 2.5 times higher than that of Au/SAPO-34.The physiochemical characterization revealed that the SAPO-34 molecular sieves were surrounded by Au and W_(18)O_(49)nanoparticles,which exhibited a strong localized surface plasmon resonance excitation around 540 nm and light absorption beyond 500 nm.The multifunctional catalysts showed a strong photothermal effect,arising from the broadened light absorption of Au and W_(18)O_(49)nanoparticles,leading to a temperature as high as 250℃on the surface of the catalysts.Mechanism study showed that the superior ethylene selectivity of W/Au/S catalysts was attributed to the moderating acidic sites of W_(18)O_(49)for methanol dehydration to ethylene.This research may provide new insight for designing heterostructures to improve photo-to-chemical conversion performance and is expected to accelerate progress toward the excellent multifunctional photothermal catalysts with broad light absorption for methanol activation and C-C bond formation.

关键词： Methanol conversion Ethylene Photothermal catalysis W_(18)O_(49) BrΦnsted-acid

Graphene-anchored sodium single atoms:A highly active and stable catalyst for transesterification reaction

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Nano Research 2024年第6期17卷 4979-4985页

作者： Song-Song Peng Yao nian Xing-Ru Song Xiang-Bin shao Chen Gu Zhi-Wei Xing Shi-Chao Qi Peng Tan You Han Xiao-Qin Liu Lin-Bing Sun State Key Laboratory of Materials-Oriented Chemical Engineering Jiangsu National Synergetic Innovation Center for Advanced Materials(SICAM)College of Chemical EngineeringNanjing Tech University30 South Puzhu RoadNanjing 211816China School of Chemical Engineering and Technology Tianjin UniversityTianjin 300072China Haihe Laboratory of Sustainable Chemical Transformations Tianjin 300192China

Solid strong base catalysts have received considerable attention in various organic reactions due to their facile separation,neglectable corrosion,and environmental friendliness.Although great progress has been made in the preparation of solid strong base catalysts,it is still challenging to avoid basic sites aggregation on support and active sites loss in reaction system.Here,we report a tandem redox strategy to prepare Na single atoms on graphene,producing a new kind of solid strong base catalyst(Na1/G).The base precursor NaNO_(3)was first reduced to Na2O by graphene(400℃)and successively to single atoms Na anchored on the graphene vacancies(800℃).Owing to the atomically dispersed of basicity,the resultant catalyst presents high activity toward the transesterification of methanol and ethylene carbonate to synthesize dimethyl carbonate(turnover frequency(TOF)value:125.7 h^(−1)),which is much better than the conventional counterpart Na2O/G and various reported solid strong bases(TOF:1.0-90.1 h^(−1)).Furthermore,thanks to the basicity anchored on graphene,the Na1/G catalyst shows excellent durability during cycling.This work may provide a new direction for the development of solid strong base catalysts.

关键词： solid strong base catalyst basic sites redox graphene single Na atoms

地质学领域科研人员参与科普:现状调查与促进建议

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地质论评 2024年第3期70卷 1113-1120页

作者：邵华胜郑念中国科普研究所北京100081

地质学领域科研人员参与科普对地质学科发展、科普高质量发展和经济社会发展有着重要的推动作用。调查结果显示,大多数地质学领域科研人员认可科普的作用和意义,愿意积极参与科普活动。然而,保障力度不够、传播渠道不畅、科普内容不深... 详细信息

地质学领域科研人员参与科普对地质学科发展、科普高质量发展和经济社会发展有着重要的推动作用。调查结果显示,大多数地质学领域科研人员认可科普的作用和意义,愿意积极参与科普活动。然而,保障力度不够、传播渠道不畅、科普内容不深入、科普能力不均衡问题相对突出。增强地质科研单位科普责任意识,强化相关科协和学会的职能,加强晋升激励、奖酬激励及考核激励体系建设,加大地质科普技能培训和经验交流,引导地质科研人员提升科普能力,是促进地质学领域科研人员参与科普的关键。

关键词：地质学科研人员科普

Intelligent diagnostic model for pterygium by combining attention mechanism and MobileNetV2

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International Journal of Ophthalmology(English edition) 2024年第7期17卷 1184-1192页

作者： Mao-nian Wu Kai He Yi-Bei Yu Bo Zheng shao-Jun Zhu Xiang-Qian Hong Wen-Qun Xi Zhe Zhang School of Information Engineering Huzhou UniversityHuzhou 313000Zhejiang ProvinceChina Zhejiang Province Key Laboratory of Smart Management and Application of Modern Agricultural Resources Huzhou UniversityHuzhou 313000Zhejiang ProvinceChina School of Mathematical Information Shaoxing UniversityShaoxing 312000Zhejiang ProvinceChina Shenzhen Eye Institute Shenzhen Eye HospitalJinan UniversityShenzhen 518040Guangdong ProvinceChina

AIM:To evaluate the application of an intelligent diagnostic model for pterygium.METHODS:For intelligent diagnosis of pterygium,the attention mechanisms—SENet,ECANet,CBAM,and Self-Attention—were fused with the lightweight MobileNetV2 model structure to construct a tri-classification model.The study used 1220 images of three types of anterior ocular segments of the pterygium provided by the Eye Hospital of Nanjing Medical University.Conventional classification models—VGG16,ResNet50,MobileNetV2,and EfficientNetB7—were trained on the same dataset for comparison.To evaluate model performance in terms of accuracy,Kappa value,test time,sensitivity,specificity,the area under curve(AUC),and visual heat map,470 test images of the anterior segment of the pterygium were used.RESULTS:The accuracy of the MobileNetV2+Self-Attention model with 281 MB in model size was 92.77%,and the Kappa value of the model was 88.92%.The testing time using the model was 9ms/image in the server and 138ms/image in the local computer.The sensitivity,specificity,and AUC for the diagnosis of pterygium using normal anterior segment images were 99.47%,100%,and 100%,respectively;using anterior segment images in the observation period were 88.30%,95.32%,and 96.70%,respectively;and using the anterior segment images in the surgery period were 88.18%,94.44%,and 97.30%,respectively.CONCLUSION:The developed model is lightweight and can be used not only for detection but also for assessing the severity of pterygium.

关键词： deep learning attention mechanism pterygium intelligent diagnosis

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基于多支路聚合的帧预测轻量化视频异常检测

图学学报 2023年第6期44卷 1173-1182页

作者：黄少年文沛然全琪陈荣元湖南工商大学计算机学院湖南长沙410205 湖南工商大学资源环境学院湖南长沙410205

复杂场景下的视频异常检测任务具有重要的研究价值与应用意义。尽管基于预测的视频异常检测方法在性能方面取得了显著进展,但仍面临诸如高模型参数量和待进一步提升的检测性能等挑战。针对这些问题,提出了一种基于多支路聚合的帧预测轻... 详细信息

复杂场景下的视频异常检测任务具有重要的研究价值与应用意义。尽管基于预测的视频异常检测方法在性能方面取得了显著进展,但仍面临诸如高模型参数量和待进一步提升的检测性能等挑战。针对这些问题,提出了一种基于多支路聚合的帧预测轻量化视频异常检测模型,模型采用多支路聚合的Transformer单元作为基本结构,显著减少了模型参数量和计算成本,并提升了检测精度。在此基础上,设计了多支路Transformer融合的编码器,在提取正常事件的时序运动特征的同时采用多分支连接操作实现多层特征融合,提升编码器特征优化能力。同时,设计了基于K-means的多支路聚类解码器,缓解正常特征多样性对异常性能检测的影响。在3个权威数据集UCSD Ped2,CUHK Avenue和ShanghaiTech上的实验结果表明,与当前主流算法相比,该模型具有更低的计算成本及良好的检测性能。

关键词：帧预测视频异常检测多支路聚和 Transformer

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某型锥形缸体斜盘式轴向柱塞泵配流冲击研究

机电工程 2022年第8期39卷 1041-1049页

作者：李少年杨攀包尚令李毅兰州理工大学能源与动力工程学院甘肃兰州730050

轴向柱塞泵柱塞腔在吸排油区的高低压转换过程中会产生配流冲击,从而引发柱塞泵产生振动以及噪声,为了减小某型斜盘式轴向柱塞泵配流副的配流冲击,建立了考虑摩擦副泄漏影响的柱塞腔油液压力变化的数学模型与AMESim仿真模型,研究了不同... 详细信息

轴向柱塞泵柱塞腔在吸排油区的高低压转换过程中会产生配流冲击,从而引发柱塞泵产生振动以及噪声,为了减小某型斜盘式轴向柱塞泵配流副的配流冲击,建立了考虑摩擦副泄漏影响的柱塞腔油液压力变化的数学模型与AMESim仿真模型,研究了不同配流结构对柱塞泵配流冲击的影响。首先,基于对目标泵的运动学分析,建立了柱塞泵配流冲击的数学模型;然后,基于建立的数学模型,利用Python软件分析了油液的可压缩性、配流盘错配角、过渡角以及减振孔结构尺寸对于柱塞腔油液压力波动的影响关系,提出了针对目标泵的优化方案;最后,基于AMESim软件的子模型二次开发功能,搭建了目标泵的仿真模型,对理论计算得出的优化方案进行了仿真分析与验证。研究结果表明:通过调整配流盘的过渡角以及减振孔等结构的尺寸,可以有效减小柱塞泵在运行过程中的配流冲击,在额定工况下目标泵的流量脉动率由35.59%减小为20.23%,降低了15.56%;该研究提出的轴向柱塞泵配流冲击优化方法,可以为轴向柱塞泵的设计和优化提供参考。

关键词：柱塞泵振动配流副/结构配流冲击油液压力摩擦副泄漏过渡角减振孔结构

基于模糊证据推理及改进TOPSIS的多属性群决策方法

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运筹与管理 2017年第6期26卷 16-23页

作者：李少年吴良刚中南大学商学院湖南长沙410083

针对不同识别框架多属性群决策问题属性准则度量的不确定性、随机性,定义基于梯形模糊数表征的属性准则评价等级相似度量,求解专家决策权重的最优解。对公共识别框架备选方案属性准则采用模糊证据推理过程综合专家评价等级置信度信息;... 详细信息

针对不同识别框架多属性群决策问题属性准则度量的不确定性、随机性,定义基于梯形模糊数表征的属性准则评价等级相似度量,求解专家决策权重的最优解。对公共识别框架备选方案属性准则采用模糊证据推理过程综合专家评价等级置信度信息;利用可严格区分属性准则评价等级的相似度量,改进TOPSIS方法中备选方案属性准则评价等级置信度距离因子,获取备选方案逼近正负理想解的贴近度。实例分析以某通信企业电信产品市场竞争力评估为例,说明基于模糊证据推理、改进TOPSIS的多属性群决策问题求解过程,从属性准则专家模糊评价等级置信度集中获取直观的待评估产品市场竞争力排序结果,验证该方法解决此类决策问题的可行性与有效性。

关键词：多属性群决策梯形模糊数评价等级相似度量置信度距离因子市场竞争力评估