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Synthesis of Bio-based Epoxy Containing Phosphine Oxide as a Reactive Additive Toward Highly Toughened and Fire-retarded Epoxy Resins

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Chinese Journal of Polymer Science 2023年第11期41卷 1733-1746,I0007页

作者： Chunxiang Wei Tianyu Gao Yu Xu Wenjie Yang guangjian dai Ruiting Li SanE Zhu Richard K.K.Yuen Wei Yang Hongdian Lu School of Energy Materials and Chemical EngineeringHefei UniversityHefei 230601China Yusuf Hamied Department of Chemistry University of CambridgeCambridge CB21EWU.K. Department of Architecture and Civil Engineering City University of Hong KongHong Kong 999077China

The integration of high mechanical toughness,impact strength as well as excellent flame-retardant properties toward epoxy resins(EPs)have always been a *** inadequate overall performance of EPs severely restricts their sustainable utilization in engineering aspects over ***,a new bio-based agent(diglycidyl ether of magnolol phosphine oxide,referred as DGEMP)derived from magnolol(classified as lignan),extracted from natural plants Magnolia officinalis,was successfully synthesized and further employed as a flameretardant reactive additive to diglycidyl ether of bisphenol A(DGEBA).As demonstration,the composite resin,DGEBA/15DGEMP(15 wt%DGEMP),achieved an Underwriters Laboratories-94 V-0 rating with a high limiting oxygen index(LOI)value(41.5%).In cone calorimeter tests,it showed that heat release and smoke production were effectively inhibited during combustion,wherein the peak heat release rate(PHRR)value of DGEBA/15DGEMP was reduced by 50%compared to neat ***,it exhibited a superior tensile strength(82.8 MPa),toughness(5.11MJ/m^(3))and impact strength(36.5 k J/m^(2)),much higher than that of neat DGEBA(49.7 MPa,2.05 MJ/m^(3)and 20.9 k J/m^(2)).Thus,it is highly anticipated that DGEMP imparts significantly improved mechanical and fire-retarded properties to conventional EPs,which holds a great potential to address the pressing challenges in EP thermosets industry.

关键词： Epoxy resin Magnolol Phosphine oxide Toughness Flame retardant

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Modelling and mechanical characteristics of PDC cutter-rock interaction by combining mixed fragmentation modes with dynamic rock strength

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PETROLEUM 2024年第3期10卷 474-482页

作者： Dong, guangjian Chen, Ping Wang, Xudong Fu, Jianhong Yang, Yingxin Southwest Petr Univ State Key Lab Oil & Gas Reservoir Geol & Exploitat Chengdu 610500 Peoples R China Southwest Petr Univ Sch Petr Engn Chengdu 610500 Peoples R China Southwest Petr Univ Period Off Southwest Petr Univ Chengdu 610500 Peoples R China Southwest Petr Univ Sch Mechatron Engn Chengdu 610500 Peoples R China

Polycrystalline diamond compact (PDC) bit is one of the most widely used drill bits for improving the rate of penetration in deep oil and gas well and geothermal well. However, the dynamic rock fragmentation mechanics characteristics of PDC bits are still unclearly. A coupled fragmentation mechanics model of PDC cutter-rock interaction is established by combining the mixed fragmentation modes with dynamic strength. The coupling influence laws of cutter angle, cutting depth, dynamic strength ratio, breaking modes on the horizontal force coefficient (HFC), vertical force coefficient (VFC) and specific energy are analyzed. The model of this paper can optimize cutter inclination angle, cutting depth and minimum specific energy. With the increase of the cutter inclination angle, the dynamic VFC changes into two modes. The definition of the dynamic modes depends on the dynamic strength ratio. As the cutting angle increases, the cutting force increases. The cutting force increases nonlinearly with increasing cutting depth. The specific energy of rock fragmentation increases nonlinearly with increasing cutting depth. With the increase of dynamic strength, the specific energy of rock fragmentation increases nonlinearly. When the input-energy increases, the rate of penetration response is divided into three stages. The results have important guiding significance for the PDC bit design and drilling parameters optimization to increase the rate of penetration and the efficiency of exploration and development.

关键词： Mechanical characteristics PDC cutter-rock interaction Mixed fragmentation modes Dynamic rock strength POSITIVE DISPLACEMENT MOTOR NUMERICAL-SIMULATION VIBRATION CHARACTERISTICS

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Dual-additives enable stable electrode-electrolyte interfaces for long life Li-SPAN batteries

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Chinese Chemical Letters 2024年第5期35卷 459-465页

作者： Zhenqiang Guo Huicong Yang Qian Wei Shengjun Xu guangjian Hu Shuo Bai Feng Li School of Materials Science and Engineering University of Science and Technology of ChinaShenyang 110016China Shenyang National Laboratory for Materials Science Institute of Metal ResearchChinese Academy of SciencesShenyang 110016China Department of Biochemistry and Molecular Biology College of Life ScienceChina Medical UniversityShenyang 110122China Dalian National Laboratory for Clean Energy Dalian 116023China Shenyang King Power Technology Co. Ltd.Shenyang 110016China

Sulfurized polyacrylonitrile(SPAN)is proposed as a promising cathode material for lithium sulfur ***,the continuous side reactions at the electrolyte-electrode interfaces as well as the slow redox kinetics of SPAN cathode deteriorate the electrochemical *** this study,an electrolyte with dual-additives comprising 2-fluoropyridine(2-FP)and lithium difluorobis(oxalato)phosphate(LiDFBOP)was used to improve the performance of Li||SPAN cells.2-FP has a lower lowest occupied molecular orbital energy than that of the solvents in the electrolyte,leading to its prior reduction.A LiF-rich film can be formed on the electrode,effectively improving the stability of the electrolyte-electrode interfaces and prolonging the ***,LiDFBOP could form an electrolyte-electrode interface film containing a large amount of Li_(x)PO_(y)F_(z) species,compensating for the kinetic deterioration caused by the lower ionic conductive of LiF formed at the electrolyte-electrode ***,an electrode-interface film with good chemical stability and high Li^(+) transport was established by LiF and Li_(x)PO_(y)F_(z)-rich *** Li||SPAN cell with the electrolyte containing dual-additives demonstrates an excellent capacity retention of 97.5%after 200 cycles at 1.0 C,25℃,comparing to 56.2%capacity retention without ***,the rate capacities of cells with dual-additives can reach 1128.1 mAh/g at 5 C,comparing to only 813.5 mAh/g using electrolyte without *** results shown that the dual-additives in electrolyte provide a promising strategy for practical application of lithium sulfur batteries with SPAN cathodes.

关键词： Sulfurized polyacrylonitrile Lithium metal Interface film 2-Fluoropyridine Difluorobis(oxalato)phosphate

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Advances in ice avalanches on the Tibetan Plateau

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Journal of Mountain Science 2024年第6期21卷 1814-1829页

作者： TANG Minggao LI Guang ZHAO Huanle XU Qiang WU guangjian YANG Wei GUO Daojing State Key Laboratory of Geohazard Prevention and Geoenvironment Protection Chengdu University of TechnologyChengdu 610059China College of Environment and Civil Engineering Chengdu University of TechnologyChengdu 610059China Institute of Tibetan Plateau Research Chinese Academy of SciencesBeijing 100101China

As some of the greatest natural disasters in the cryosphere,ice avalanches(IAs)seriously threaten lives and cause catastrophic damage to the resource environment,but a comprehensive overview of the state of knowledge on IAs remains *** summarized 63 IAs on the Tibetan Plateau(TP)since the 20th century,of which,over 20 IAs occurred after the 21st *** distributions of IAs are mainly concentrated in the southeastern and northwestern TP,and the occurrence time of IAs is mostly concentrated from July to *** highlight recent advances in mechanical properties and genetic mechanisms of IAs and emphasize that temperature,rainfall,and seismicity are the inducing *** failure modes of IAs are summarized into 6 categories by examples:slip pulling type,slip toppling type,slip breaking type,water level collapse type,cave roof collapse type,and wedge failure ***,we deliver recommendations concerning the risk assessment and prediction of *** results provide important scientific value for addressing climate change and resisting glacier-related hazards.

关键词： Ice avalanche Global warming Genetic mechanism Risk assessment Tibetan Plateau

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Functional near-infrared spectroscopy in non-invasive neuromodulation

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Neural Regeneration Research 2024年第7期19卷 1517-1522页

作者： Congcong Huo Gongcheng Xu Hui Xie Tiandi Chen guangjian Shao Jue Wang Wenhao Li daifa Wang Zengyong Li Beijing Advanced Innovation Center for Biomedical Engineering Key Laboratory for Biomechanics and Mechanobiology of Ministry of EducationSchool of Biological Science and Medical EngineeringBeihang UniversityBeijingChina Beijing Key Laboratory of Rehabilitation Technical Aids for Old-Age Disability National Research Center for Rehabilitation Technical AidsBeijingChina School of Mechatronic Engineering and Automation Foshan UniversityFoshanGuangdong ProvinceChina School of Rehabilitation Engineering Beijing College of Social AdministrationBeijingChina Key Laboratory of Neuro-functional Information and Rehabilitation Engineering of the Ministry of Civil Affairs BeijingChina

Non-invasive cerebral neuromodulation technologies are essential for the reorganization of cerebral neural networks,which have been widely applied in the field of central neurological diseases,such as stroke,Parkinson’s disease,and mental *** significant advances have been made in neuromodulation technologies,the identification of optimal neurostimulation paramete rs including the co rtical target,duration,and inhibition or excitation pattern is still limited due to the lack of guidance for neural *** r,the neural mechanism unde rlying neuromodulation for improved behavioral performance remains poorly ***,advancements in neuroimaging have provided insight into neuromodulation *** near-infrared spectroscopy,as a novel non-invasive optical brain imaging method,can detect brain activity by measuring cerebral hemodynamics with the advantages of portability,high motion tole rance,and anti-electromagnetic *** functional near-infra red spectroscopy with neuromodulation technologies offe rs an opportunity to monitor the cortical response,provide realtime feedbac k,and establish a closed-loop strategy integrating evaluation,feedbac k,and intervention for neurostimulation,which provides a theoretical basis for development of individualized precise neuro *** aimed to summarize the advantages of functional near-infra red spectroscopy and provide an ove rview of the current research on functional near-infrared spectroscopy in transcranial magnetic stimulation,transcranial electrical stimulation,neurofeedback,and braincomputer ***,the future perspectives and directions for the application of functional near-infrared spectroscopy in neuromodulation are *** conclusion,functional near-infrared spectroscopy combined with neuromodulation may promote the optimization of central pellral reorganization to achieve better functional recovery form central nervous system

关键词： brain-computer interface cerebral neural networks functional near-infrared spectroscopy neural circuit neurofeedback neurological diseases neuromodulation non-invasive brain stimulation transcranial electrical stimulation transcranial electrical stimulation

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Regulating interfacial chemistry and kinetic behaviors of F/Mo co-doping Ni-rich layered oxide cathode for long-cycling lithium-ion batteries over-20°C-60°C

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Journal of Energy Chemistry 2024年第7期94卷 449-457页

作者： Siqi Guan Lin Tao Pei Tang Ruopian Fang Huize Wu Nan Piao Huicong Yang guangjian Hu Xin Geng Lixiang Li Baigang An Feng Li Institute of Energy Materials and Electrochemistry Research University of Science and Technology LiaoningAnshan 114051LiaoningChina Shenyang National Laboratory for Materials Science Institute of Metal ResearchChinese Academy of SciencesShenyang 110016LiaoningChina School of Materials Science and Engineering University of Science and Technology of ChinaShenyang 110016LiaoningChina Shenyang King Power Tech.Co. Ltd.Shenyang 110016LiaoningChina School of Chemical Engineering The University of New South WalesSydney 2052NSWAustralia

Ni-rich layered oxide cathodes have shown promise for high-energy lithium-ion batteries(LIBs)but are usually limited to mild environments because of their rapid performance degradation under extreme temperature conditions(below0°C and above 50 °C).Here,we report the design of F/Mo co-doped LiNi_(0.8)Co_(0.1)Mn_(0.1)O_(2)(FMNCM)cathode for high-performance LIBs from-20 to 60°C.F^(-) doping with high electronegativity into the cathode surface is found to enhance the stability of surface lattice structure and protect the interface from side reactions with the electrolyte by generating a LiF-rich surface ***,the Mo^(6+) doping suppresses phase transition,which blocks Li^(+)/Ni^(2+) mixing,and stabilizes lithium-ion diffusion ***,the FMNCM cathode demonstrates excellent cycling stability at a high cutoff voltage of 4.4 V,even at 60°C,maintaining 90.6%capacity retention at 3 C after 150 ***,at temperatures as low as-20°C,it retains 77.1%of its room temperature capacity,achieving an impressive 97.5%capacity retention after 500 *** stable operation under wide temperatures has been further validated in practical Ah-level *** study sheds light on both fundamental mechanisms and practical implications for the design of advanced cathode materials for wide-temperature LIBs,presenting a promising path towards high-energy and long-cycling LIBs with temperatureadaptability.

关键词： Anion-cation co-doping Wide temperature operation Ni-richlayered cathode Phase transition Surface/interface

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盐酸环丙沙星-ε-聚赖氨酸微球的制备及释药性能研究

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化工新型材料 2011年第8期39卷 115-118页

作者：代光剑欧阳玉徐鼎峰蔡祥吴婷欧阳友生施庆珊谭绍早暨南大学化学系广州510632 广东省微生物研究所广州510070

采用乳化-化学交联法制备了盐酸环丙沙星-ε-聚赖氨酸(CH-PL)微球。利用扫描电镜、红外光谱和ZetasizeNano ZS对载药微球进行表征,并考察了CH-PL微球在0.1mol/L HCl(pH=1.2)溶液中的释药行为以及不同交联剂用量对载药微球释药速率的影... 详细信息

采用乳化-化学交联法制备了盐酸环丙沙星-ε-聚赖氨酸(CH-PL)微球。利用扫描电镜、红外光谱和ZetasizeNano ZS对载药微球进行表征,并考察了CH-PL微球在0.1mol/L HCl(pH=1.2)溶液中的释药行为以及不同交联剂用量对载药微球释药速率的影响。结果表明:成功制备了球形圆整、分散性好、平均粒径约为15μm的CH-PL微球,其最大载药量和包封率分别为5.1%和42.8%;CH-PL微球具有良好的缓释效果,释药过程符合Higuichi机制,且微球的释药速率随交联剂用量的增加而变慢。

关键词： ε-聚赖氨酸盐酸环丙沙星微球缓释

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中国式现代化背景下我国关税政策优化的思考

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税务研究 2024年第7期 114-119页

作者：许光建黎珍羽中国人民大学公共管理学院

关税是调控经济的重要政策工具之一。我国加入世界贸易组织以来,对关税政策进行了一系列调整,在降低关税总水平、促进生产、推动对外贸易发展以及维护国家利益和安全等方面取得显著成就。中国式现代化赋予关税政策新的要求,包括促进低... 详细信息

关税是调控经济的重要政策工具之一。我国加入世界贸易组织以来,对关税政策进行了一系列调整,在降低关税总水平、促进生产、推动对外贸易发展以及维护国家利益和安全等方面取得显著成就。中国式现代化赋予关税政策新的要求,包括促进低碳可持续发展、兼顾生产与消费、统筹国内国际两个市场两种资源和巩固总体安全等。未来,我国需要通过贯彻绿色税收理念、以关税调整推进高水平对外开放、加强关税政策供给、深化国际税收合作、积极参与国际税收改革等措施促进关税政策优化,以进一步服务中国式现代化。

关键词：中国式现代化关税政策世界贸易组织国际税收

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人工智能技术赋能情报工作的历程与当前思考

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信息资源管理学报 2024年第2期14卷 4-20页

作者：李广建潘佳立北京大学信息管理系北京100871

本文系统探讨了人工智能技术的演进及其在情报工作中的应用,揭示了人工智能赋能情报工作在思想、特征、技术方法和场景应用上的新变化。从基于规则的范式到基于基础模型的阶段,人工智能技术为情报工作的智能化提供了新机遇,但同时也引... 详细信息

本文系统探讨了人工智能技术的演进及其在情报工作中的应用,揭示了人工智能赋能情报工作在思想、特征、技术方法和场景应用上的新变化。从基于规则的范式到基于基础模型的阶段,人工智能技术为情报工作的智能化提供了新机遇,但同时也引发了伦理、法律、隐私等新挑战。本文指出了情报领域在新时期应该关注的问题和挑战,并提出了针对这些问题和挑战的对策,以期为情报领域的稳定发展提供有益的建议。

关键词：人工智能技术基础模型数智赋能情报工作应用挑战

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我国南方丘陵山区耕地地块精准提取方法——以福建省浦城县为例

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遥感信息 2024年第3期39卷 55-60页

作者：吴瑞姣陈光剑福建省地质测绘院福州350011

鉴于南方丘陵山区耕地地块具有多样的尺寸和种植结构,传统语义分割方法存在精度低、边界吻合度差等问题,提出了一种顾及地块边界和形状特征多任务学习和注意力机制的高分辨率遥感图像提取方法。该方法构建了多任务神经网络模型FPEM-Net... 详细信息

鉴于南方丘陵山区耕地地块具有多样的尺寸和种植结构,传统语义分割方法存在精度低、边界吻合度差等问题,提出了一种顾及地块边界和形状特征多任务学习和注意力机制的高分辨率遥感图像提取方法。该方法构建了多任务神经网络模型FPEM-Net,主要包括耕地分割主任务以及与地块提取密切相关的轮廓检测和距离估计两个辅助任务。引入了CBAM注意力模块以增强特征的表达能力并减少冗余特征,并通过共同优化多任务损失函数训练模型。该方法成功应用于福建省浦城县,实验结果显示在测试集上表现出色,Hausdorff距离最小,像素准确率和交并比分别达到93.12%和93.55%。与Psi-Net相比,像素准确率提升了1.42%,交并比提升了3.4%;相较于UNet,像素准确率提升了14.11%,交并比提升了15.34%。该方法在规则和不规则耕地地块以及复杂种植结构的边界方面表现出良好的泛化能力,与实际耕地地块分布格局更加吻合,具有较好的应用潜力。

关键词：耕地地块高分辨率图像深度学习多任务学习注意力机制

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