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引入Transformer的道路小目标检测

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计算机工程与设计 2024年第1期45卷 95-101页

作者：李丽芬黄如华北电力大学(保定)计算机系河北保定071003

针对道路场景中检测小目标时漏检率较高、检测精度低的问题,提出一种引入Transformer的道路小目标检测算法。在原YOLOv4算法基础上,对多尺度检测进行改进,把浅层特征信息充分利用起来;设计ICvT(improved convolutional vision transform... 详细信息

针对道路场景中检测小目标时漏检率较高、检测精度低的问题,提出一种引入Transformer的道路小目标检测算法。在原YOLOv4算法基础上,对多尺度检测进行改进,把浅层特征信息充分利用起来;设计ICvT(improved convolutional vision transformer)模块捕获特征内部的相关性,获得上下文信息,提取更加全面丰富的特征;在网络特征融合部分嵌入改进后的空间金字塔池化模块,在保持较小计算量的同时增加特征图的感受野。实验结果表明,在KITTI数据集上,算法检测精度达到91.97%,与YOLOv4算法相比,mAP提高了2.53%,降低了小目标的漏检率。

关键词：小目标检测深度学习 YOLOv4算法多尺度检测 Transformer 空间金字塔池化特征融合

Leaching kinetics of fluorine during the aluminum removal from spent li-ion battery cathode materials

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Journal of Environmental Sciences 2024年第4期138卷 312-325页

作者： Shengjie li Jianxin Zhu Research Center for Eco-Environmental Sciences Chinese Academy of SciencesBeijing 100085China University of Chinese Academy of Sciences Beijing 100049China

The high content of aluminum(Al)impurity in the recycled cathode powder seriously affects the extraction efficiency of Nickel,Cobalt,Manganese,and lithium resources and the actual commercial value of recycled materials,so Al removal is crucially important to conform to the industrial standard of spent li-ion battery cathode materials.In this work,we systematically investigated the leaching process and optimum conditions associated with Al removal from the cathode powder materials collected in a wet cathode-powder peeling and recycling production line of spent li-ion batteries(liBs).Moreover,we specifically studied the leaching of fluorine(F)synergistically happened along with the removal process of Al,which was not concerned about in other studies,but one of the key factors affecting pollution prevention in the recovery process.The mechanism of the whole process including the leaching of Al and F from the cathode powder was indicated by using NMR,FTIR,and XPS,and a defluoridation process was preliminarily investigated in this study.The leaching kinetics of Al could be successfully described by the shrinking core model,controlled by the diffusion process and the activation energy was 11.14 kJ/mol.While,the leaching of F was attributed to the dissolution of liPF6and decomposition of PVDF,and the kinetics associated was described by Avrami model.The interaction of Al and F is advantageous to realize the defluoridation to some degree.It is expected that our investigation will provide theoretical support for the large-scale recycling of spent liBs.

关键词： Al removal F leaching Cathode powder Heating alkali leaching Leaching kinetics

Palladium-catalyzed multi components oxy-aminofluorination and aminofluorination of gem-difluoroalkenes

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Chinese Chemical Letters 2024年第2期35卷 420-425页

作者： fen Wu Xin li Junbiao Chang Dachang Bai State Key Laboratory of Antiviral Drugs NMPA Key Laboratory for Research and Evaluation of Innovative DrugKey Laboratory of Green Chemical Media and ReactionsMinistry of EducationSchool of Chemistry and Chemical EngineeringPingyuan LaboratoryHenan Normal UniversityXinxiang 453007China State Key Laboratory of Organometallic Chemistry Shanghai Institute of Organic ChemistryChinese Academy of SciencesShanghai 200032China

Organofluorine compounds are widely used in the realm of drug discovery and material science.Herein,we developed palladium catalyzed intermolecular aminofluorination and oxy-aminofluorination of gem‑difluoroalkenes with N-fluorobenzenesulfonimide(NFSI),in which NFSI was used as the nitrogen source and oxidant.The reaction provides an efficient and straightforward synthesis route of a series ofα-trifluoromethyl benzylic amines.Notably,three/four components oxy-aminofluorination processes were realized to giveα-trifluoromethyl benzylic ether with a terminal amino group,which proceed through C(sp^(3))-O bond cleavage of easily available ether and simultaneous introduced a fluorine,an amino and an oxy substituent in one pot with excellent regioselectivity.The divergent reactivity not only included the incorporation of one ether molecular,but also much more challenged two ether insertion with excellent selectivity through succession C(sp^(3))-O bonds cleavage.This protocol allows for concise synthesis of high value amines with fluoroalkyl-substituents and selectively transformation of easily available ethers by high-valent palladium catalysis.

关键词： Palladium Multi components Aminofluorination Oxy-aminofluorination C(sp^(3))-O bond cleavage

Plant-based dietary patterns and risk of esophageal cancer:A prospective cohort study spanning 17 years

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Chinese Journal of Cancer Research 2024年第1期36卷 36-45页

作者： Xiaorui Zhang Feifan He Jiayue li Ru Chen Xinqing li li li fen liu Shaoming Wang Wenqiang Wei Department of Epidemiology and Health Statistics School of Public HealthBeijing Municipal Key Laboratory of Clinical EpidemiologyCapital Medical UniversityBeijing 100069China National Central Cancer Registry office National Cancer Center/National Clinical Research Center for Cancer/Cancer HospitalChinese Academy of Medical Sciences and Peking Union Medical CollegeBeijing 100021China Department of Cancer Epidemiology National Cancer Center/National Clinical Research Center for Cancer/Cancer HospitalChinese Academy of Medical Sciences and Peking Union Medical CollegeBeijing 100021China

Objective: Plant-based diets have multiple health benefits for cancers;however, little is known about the association between plant-based dietary patterns and esophageal cancer(EC).This study presents an investigation of the prospective associations among three predefined indices of plant-based dietary patterns and the risk of EC.Methods: We performed endoscopic screening for 15,709 participants aged 40-69 years from two high-risk areas of China from January 2005 to December 2009 and followed the cohort until December 31, 2022. The overall plant-based diet index(PDI), healthful plant-based diet index(h PDI), and unhealthful plant-based diet index(u PDI), were calculated using survey responses to assess dietary patterns. We applied Cox proportional hazard regression to estimate the multivariable hazard ratios(HRs) and 95% confidence intervals(95% CIs) of EC across 3plant-based diet indices and further stratified the analysis by subgroups.Results: The final study sample included 15,184 participants in the cohort. During a follow-up of 219,365person-years, 176 patients with EC were identified. When the highest quartile was compared with the lowest quartile, the pooled multivariable-adjusted HR of EC was 0.50(95% CI, 0.32-0.77) for h PDI. In addition, the HR per 10-point increase in the h PDI score was 0.42(95% CI, 0.27-0.66) for ECs. Conversely, u PDI was positively associated with the risk of EC, and the HR was 1.80(95% CI, 1.16-2.82). The HR per 10-point increase in the u PDI score was 1.90(95% CI, 1.26-2.88) for ECs. The associations between these scores and the risk of EC were consistent in most subgroups. These results remained robust in sensitivity analyses.Conclusions: A healthy plant-based dietary pattern was associated with a reduced risk of EC. Emphasizing the healthiness and quality of plant-based diets may be important for preventing the development of EC.

关键词： Esophageal cancer diet dietary pattern epidemiology nutrition prospective cohort study

The dawn−dusk asymmetry in mesosphere and lower thermosphere temperature disturbances during geomagnetic storms at high latitude

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Earth and Planetary Physics 2024年第2期8卷 356-367页

作者： GuanChun Wei JianYong Lu fen Tang JingYuan li Meng Sun Institute of Space Weather School of Atmospheric PhysicsNanjing University of Information Science&TechnologyNanjing 210044China College of Information and Communication National University of Defense TechnologyWuhan 430019China

Utilizing observations by the Sounding of the Atmosphere using Broadband Emission Radiometry(SABER)instrument,we quantitatively assessed the dawn-dusk asymmetry in temperature disturbances within the high-latitude mesosphere and lower thermosphere(MLT)during the main phase of geomagnetic storms in this study.An analysis of five geomagnetic superstorm events indicated that during the main phase,negative temperature disturbances were more prevalent on the dawn side than on the dusk side in the high-latitude MLT region.Results of a statistical analysis of 54 geomagnetic storm events also revealed a notable disparity in temperature disturbances between the dawn and dusk sides.At high latitudes,38.2%of the observational points on the dawn side exhibited negative temperature disturbances(less than−5 K),whereas on the dusk side,this percentage was only 29.5%.In contrast,at mid-latitudes,these proportions were 34.1%and 36.5%,respectively,showing no significant difference.We also conducted a statistical analysis of temperature disturbances at different altitudes,which revealed an increase in the proportion of warming disturbances with altitude.Conversely,the proportion of cooling disturbances initially rose with altitude,reaching a peak around 105 km,and subsequently decreased.These temperature disturbance differences could be explained by the day-night asymmetry in vertical wind disturbances during storm conditions.

关键词： dawn dusk asymmetry SABER(Sounding of the Atmosphere using Broadband Emission Radiometry) geomagnetic storms mesosphere and lower thermosphere

Notoginsenoside Ft1 inhibits colorectal cancer growth by increasing CD8^(+)T cell proportion in tumor-bearing mice through the USP9X signaling pathway

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Chinese Journal of Natural Medicines 2024年第4期22卷 329-340页

作者： fenG Yutao li Yuan MA fen WU Enjiang CHENG Zewei ZHOU Shiling WANG Zhengtao YANG li SUN Xun ZHANG Jiwei Shanghai Key Laboratory of Compound Chinese Medicines The MOE Key Laboratory for Standardization of Chinese MedicinesInstitute of Chinese Materia MedicaShanghai University of Traditional Chinese MedicineShanghai 201203China Gastrointestinal surgery Longhua HospitalShanghai University of Traditional Chinese MedicineShanghai 200032China

The management of colorectal cancer(CRC)poses a significant challenge,necessitating the development of innovative and effective therapeutics.Our research has shown that notoginsenoside Ft1(Ng-Ft1),a small molecule,markedly inhibits subcutaneous tumor formation in CRC and enhances the proportion of CD8^(+)T cells in tumor-bearing mice,thus restraining tumor growth.Investigation into the mechanism revealed that Ng-Ft1 selectively targets the deubiquitination enzyme USP9X,undermining its role in shieldingβ-catenin.This leads to a reduction in the expression of downstream effectors in the Wnt signaling pathway.These findings indicate that Ng-Ft1 could be a promising small-molecule treatment for CRC,working by blocking tumor progression via the Wnt signaling pathway and augmenting CD8^(+)T cell prevalence within the tumor environment.

关键词： Notoginsenoside Ft1 Colorectal cancer CD8^(+)T cell Ubiquitin-specific peptidase 9 X-linked β-Catenin Wnt

Photo-induced 1,2-aryl migration of 2-chloro-1-arylpropanone under batch and flow conditions:Rapid,scalable and sustainable approach to 2-arylpropionic acids

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Chinese Chemical Letters 2024年第2期35卷 366-369页

作者： Qiao li Minjie liu Meifen Jiang li Wan Yingtang Ning fen-Er Chen College of Chemical Engineering Zhejiang University of TechnologyHangzhou 310014China Engineering Center of Catalysis and Synthesis for Chiral Molecules Fudan UniversityShanghai 200433China Shanghai Engineering Center of Industrial Catalysis for Chiral Drugs Shanghai 200433China Institute of Pharmaceutical Science and Technology Zhejiang University of TechnologyHangzhou 310014China

We report the photo-mediated 1,2-aryl migration of 2‑chloro-1-arylpropanones to 2-arylpropionic acids using HCOONa as an acid scavenger.This pragmatically focused study obviates the multiple-step sequence in the industrially employed,ZnO-promoted rearrangement strategy,and offers rapid access to various 2-arylpropionic acids under environmentally friendly conditions.Furthermore,the successful transfer of this batch photochemistry to a continuous flow platform led to improved scalability and enabled the gram-scale synthesis of loxoprofen.

关键词： Green chemistry Flow chemistry 2-Arylpropionic acids Photo-Favorskii reaction

Additives strategies to improving cycling stability of li metal batteries by modifying electrode electrolyte interphases

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Progress in Natural Science:Materials International 2024年第2期34卷 338-344页

作者： Yuan li Pengfei Huang Chunyu Cui Xiaoyuan Ma li Chen Zekun li linhai li Yuhong Tian School of Biological and Chemical Engineering Guangxi University of Science and Technology School of College of Chemistry and Chemical Engineering Hunan University Isky Future Energy Institute

li metal batteries（LMBs） have attracted much attention due to the ultra-high theoretical capacity of the li metal anode（LMA）.However,the uncontrollable dendrites growth and low coulombic efficiency hinder their practical application.Here,we explore 3,5-difluoropyridine（2F-BD） as a novel electrolyte additive to enable highperformance LMBs.The 2F-BD additive participates in and modifies the solvation structure of li ions by reducing the coordinated number of PF6-at the electrode surface,leading to the formation of a liF and li3N-rich solid electrolyte interphase（SEI）.The liF component increases the robustness of SEI and suppresses the formation of li dendrites,while the li3N component facilitates the transportation and reaction kinetics of li ions.As a result,the li‖li symmetric cell presents a stable cycling performance of up to 500 h at a current density of 1 mA cm-2.After coupling with liFePO4cathode,the obtained full cell achieves high specific capacities of 106.06 mA h g-1and 84.98 mA h g-1at 2.55 mA cm-2and 5.10 mA cm-2,respectively,and maintains a high capacity retention of84.0% after 1000 cycles at 0.13 mA cm-2,with an average cycling CE of 99.58%.

关键词： Electrolyte additive li dendrites li metal batteries liF and li3N-Rich electrode-electrolyte interphase liFePO4 cathode

ZIF-8 modified by isocyanate as a photocatalytic antibacterial agent

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Rare Metals 2024年第6期43卷 2708-2718页

作者： Yi-Ning Zhang Zhen Pei Zi-Hao Wang Chong-En Wang fen-fen liang li-Qiao Wei College of Architecture Taiyuan University of Technology Key Laboratory of Interface Science and Engineering in Advanced Materials of Taiyuan University of Technology Ministry of Education Department of Materials Science and Engineering Shanxi Institute of Technology Shanxi-Zheda Institute of Advanced Materials and Chemical Engineering

Zeolite imidazole skeleton（ZIF-8） is a promising option for self-cleaning of building exterior walls due to its large specific surface area,high antibacterial activity and low biotoxicity.However,it suffers from low antibacterial efficiency and yield under visible light irradiation.To address the issues,we developed the photocatalytic materials T-ZIF-8-TDI（thermally treated-ZIF-8-toluene 2,4-diisocyanate） by modifying ZIF-8 with thermal oxygen sensitization and chemical bonding.The results show that the yield of T-ZIF-8-TDI photocatalytic antibacterial agent is increased to 11.5 times of that of T-ZIF-8,while maintaining the crystal structure of T-ZIF-8 and thermal stability up to 60℃.Furthermore,T-ZIF-8-TDI exhibits extended optical response range to the nearinfrared region,significantly narrowed band gap,improved photogenerated elec tron-hole separation efficiency,reduced recombination rate,and excellent photocatalytic performance.When the concentration of antibacterial agent is 600 mg·L-1,the antibacterial rate of Escherichia coli（E.coli） reaches 99.99% irradiated by visible light for30 min,and when the concentration of antibacterial agent is 200 mg·L-1,the antibacterial rate of Staphylococcus aureus（S.aureus） reaches 99.99% irradiated by visible light for 25 min.We also analyzed the reasons in detail from the aspects of bacterial species and antibacterial mechanism,and proposed the antibacterial mechanism of·O2-and h+as the main active species.These findings suggest that T-ZIF-8-TDI photocatalytic antibacterial agent has potential for use in self-cleaning of building exterior walls.

关键词： ZIF-8 Hot oxygen sensitization Modified by isocyanate Antimicrobial performance Photocatalytic antibacterial mechanism