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Rare Metals 2024年第6期43卷 2574-2584页

作者： Da-Wei Zou Xing-Guang fu Gao-Bang chen Yi-Fan Liu Bao-Shan Wu Xian Jian School of Materials and Energy University of Electronic Science and Technology of ChinaChengdu 611731China Yangtze Delta Region institute(Huzhou) University of Electronic Science and Technology of ChinaHuzhou 31300lChina

Forming an ultrathin conducting layer on a fluorinated carbon(CFx)surface for reducing severe electrochemical polarization in lithium/fluorinated carbon primary batteries(Li/CF_(x))remains a considerable challenge for achieving batteries with excellent rate ***,CFxwas modified by using acetylene/argon mixture plasma combined with MnO_(2)*** CF_(x)/C/MnO_(2)composite effectively reduced the voltage hysteresis and improved the electrochemical performance of Li/CF_(x).The excellent rate performance of CF_(x)/C/MnO_(2)was due to the high electrochemical activity provided by the atomicscale conductive carbon layer and ultrafine MnO_(2)*** with pristine CF_(x),the charge transfer resistance of the optimized CF_(x)/C/MnO_(2)decreased from 218.5 to 48.2Ω,the discharge rate increased from 2C to 10C,and the power density increased from 3.11 to 13.44 kW·g^(-1),The intrinsic reason for the enhanced rate performance was attributed to the fact that the ultrathin carbon layer acted as a conductive bridge to reduce the voltage hysteresis at the initial stage of the Li/CF_(x)discharge,and the high electrochemical activity of the ultrafine MnO_(2)particles provided a faster lithium-ion diffusion rate.

关键词： C_(2)H_(2)/Ar plasma Fluorinated carbon Lithium primary battery MnO_(2)

Bending Failure Mode and Prediction Method of the Compressive Strain Capacity of A Submarine Pipeline with Dent Defects

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China Ocean Engineering 2024年第4期38卷 636-647页

作者： HOU fu-heng JIA Lu-sheng chen Yan-fei ZHANG Qi ZHONG Rong-feng WANG Chun-sha School of Mechanical and Transportation Engineering China University of PetroleumBeijingBeijing 102249China CNOOC Research institute Ltd.Beijing 100028 China

A dent is a common type of defects for submarine *** submarine pipelines,high hydrostatic pressure and internal pressure are the main *** pipelines bend due to complex subsea conditions,the compression strain capacity may be *** into the local buckling failure and accurate prediction of the compressive strain capacity are important.A finite element model of a pipeline with a dent is *** buckling failure under a bending moment is investigated,and the compressive strain capacity is *** effects of different parameters on pipeline local buckling are *** results show that the dent depth,external pressure and internal pressure lead to different local buckling failure modes of the pipeline.A higher internal pressure indicates a larger compressive strain capacity,and the opposite is true for external *** the ratio of external pressure to collapse pressure of intact pipeline is greater than 0.1,the deeper the dent,the greater the compressive strain capacity of the *** as the ratio is less than 0.1,the opposite is *** the basis of these results,a regression equation for predicting the compressive strain capacity of a dented submarine pipeline is proposed,which can be referred to during the integrity assessment of a submarine pipeline.

关键词： submarine pipeline dent defect bending load local buckling compressive strain capacity

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超声实验中谱比法衰减的散射与本征吸收特性

地球物理学报 2018年第3期61卷 1083-1094页

作者：周浩符力耘矿产地球化学国家重点实验室中国科学院地球化学研究所贵阳550002 中国科学院大学北京100049 中国石油大学(华东)地球科学与技术学院青岛266580

实际地球介质的弹性波衰减,无论是对于地球内部结构反演、含油气储层描述,还是对于地震岩石物理本身的基础研究而言,都十分重要.通过岩石物理实验测量岩石的弹性波衰减是相关研究的基本手段,而谱比法是一种最常用的测量方法.利用谱比法... 详细信息

实际地球介质的弹性波衰减,无论是对于地球内部结构反演、含油气储层描述,还是对于地震岩石物理本身的基础研究而言,都十分重要.通过岩石物理实验测量岩石的弹性波衰减是相关研究的基本手段,而谱比法是一种最常用的测量方法.利用谱比法测量的弹性波衰减,简称谱比法衰减,由介质的本征吸收特性和非均质散射特性共同决定.然而,在谱比法理论中,没有将这两种衰减特性的作用区分对待.因此,实验室测量的谱比法衰减中是否含有散射特性,其散射特性是否可以忽略,常不明确.本文基于对岩石物理实验中样品波形特征的基本认识,通过能流理论描述了弹性波的本征吸收和非均质散射过程,以及对应的尾波形成机理.文章还应用能流理论测量岩石的弹性波衰减,即能流法衰减.无论是通过理论推导,还是通过实验验证,谱比法衰减与能流法衰减都显示出良好的一致性.这两种直达波衰减的一致性暗示了谱比法衰减中存在着两种衰减特性.文中还对比分析了谱比法衰减与喷射流本征衰减的实验结果,该结果同样展示了谱比法衰减中可能存在着散射特性.因此,通过能流理论,可以利用样品波形的尾波特征定性判断谱比法衰减中可能存在的散射特性.即异常明显的尾波振幅可能意味着强烈的直达波非均质散射,谱比法衰减中的散射特性因而不可忽略.

关键词：谱比法散射衰减本征衰减尾波

Recent advances and practical challenges of high-energy-density flexible lithium-ion batteries

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Frontiers of Chemical Science and Engineering 2024年第8期18卷 79-98页

作者： Guangxiang Zhang Xin chen Yulin Ma Hua Huo Pengjian Zuo Geping Yin Yunzhi Gao Chuankai fu State Key Laboratory of Space Power-Sources Harbin Institute of TechnologyHarbin 150001China MIIT Key Laboratory of Critical Materials Technology for New Energy Conversion and Storage School of Chemistry and Chemical EngineeringHarbin Institute of TechnologyHarbin 150001China

With the rapid iteration and update of wearable flexible devices,high-energy-density flexible lithium-ion batteries are rapidly ***,energy density,and safety are all important indicators for flexible lithium-ion batteries,which can be determined jointly by material selection and structural ***,recent progress on high-energy-density electrode materials and flexible structure designs are *** electrode materials and the next-generation high-energy-density electrode materials are analyzed in *** electrolytes with high safety and excellent flexibility are classified and *** strategies to increase the mass loading of active materials on the electrodes by designing the current collector and electrode structure are discussed with keys of representative *** the novel configuration structures to enhance the flexibility of batteries are *** the end,it is pointed out that it is necessary to quantify the comprehensive performance of flexible lithium-ion batteries and simultaneously enhance the energy density,flexibility,and safety of batteries for the development of the next-generation high-energy-density flexible lithium-ion batteries.

关键词： lithium-ion batteries flexibility high energy density safety

A New Algorithm of Rain Type Classification for GPM Dual-Frequency Precipitation Radar in Summer Tibetan Plateau

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Advances in Atmospheric sciences 2024年第11期41卷 2093-2111页

作者： Yunfei fu Liu YANG Zhenhao WU Peng ZHANG Songyan GU Lin chen Sun NAN School of Earth and Space sciences CMA-USTC Laboratory of Fengyun Remote SensingUniversity of Science and Technology of ChinaHefei 230026China Hubei Key Laboratory for Heavy Rain Monitoring and Warning Research Institute of Heavy RainChina Meteorological AdministrationWuhan 430205China National Satellite Meteorological Center China Meteorological AdministrationBeijing 100081China

In this study, a new rain type classification algorithm for the Dual-Frequency Precipitation Radar(DPR) suitable over the Tibetan Plateau(TP) was proposed by analyzing Global Precipitation Measurement(GPM) DPR Level-2 data in summer from 2014 to 2020. It was found that the DPR rain type classification algorithm(simply called DPR algorithm) has mis-identification problems in two aspects in summer TP. In the new algorithm of rain type classification in summer TP,four rain types are classified by using new thresholds, such as the maximum reflectivity factor, the difference between the maximum reflectivity factor and the background maximum reflectivity factor, and the echo top height. In the threshold of the maximum reflectivity factors, 3. d BZ and 18 d BZ are both thresholds to separate strong convective precipitation, weak convective precipitation and weak precipitation. The results illustrate obvious differences of radar reflectivity factor and vertical velocity among the three rain types in summer TP, such as the reflectivity factor of most strong convective precipitation distributes from 15 d BZ to near 3. d BZ from 4 km to 13.km, and increases almost linearly with the decrease in height. For most weak convective precipitation, the reflectivity factor distributes from 15 d BZ to 28 d BZ with the height from 4 km to 9 km. For weak precipitation, the reflectivity factor mainly distributes in range of 15–25 d BZ with height within 4–10 km. It is also shows that weak precipitation is the dominant rain type in summer TP, accounting for 40%–80%,followed by weak convective precipitation(25%–40%), and strong convective precipitation has the least proportion(less than 3.%).

关键词： satellite precipitation radar rain type classification method Tibetan Plateau strong convective precipitation

SYNTHESIS AND POLYMERIZATION OF TRI(2-PYRIDYL)METHYL METHACRYLATE

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chinese Journal of Polymer Science 1999年第3期17卷 295-298页

作者： Chuan-fu chen Yong-hong Yang fu Xi {3. of Chemistry, chinese academy of sciences, Beijing 100080, China chinese Acad Sci Inst Chem Beijing 100080 Peoples R China

A novel methacrylate monomer with bulky side group, tri(2-pyridyl)methyl methacrylate (Tr2PyMA), was synthesized and polymerized. The polymer obtained by radical polymerization exhibits high isotactic tacticity.

关键词： optical activity tri(2-pyridyl)methyl methacrylate

p3. Signaling Mediates Naringin-Induced Osteogenic Differentiation of Porcine Metanephric Mesenchymal Cells

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chinese Journal of Integrative Medicine 2024年第9期30卷 818-825页

作者： JI Peng-cheng XIE Yuan-sheng GUO Wen-kai fu Bo chen Xiang-mei chinese PLA Medical School Beijing100853China Department of Nephrology First Medical Center of Chinese PLA General HospitalChinese PLA Institute of NephrologyState Key Laboratory of Kidney DiseasesNational Clinical Research Center for Kidney DiseasesBeijing Key Laboratory of Kidney DiseasesBeijing100853China School of Medicine Nankai UniversityTianjin300071China

Objective:To explore the potential of metanephric mesenchymal cells(MMCs)for osteogenesis and naringin’s ability to enhance this process and its molecular ***:Porcine MMCs at 70 days of gestation were used as tool cells,cultured in osteogenic induction medium,identified by immunocytochemistry *** potential of porcine MMCs and naringin’s ability to enhance this process was tested by detecting changes in cell viability,alkaline phosphatase(ALP)activity,the expression of runt-related transcription factor 2(Runx2),osteopontin(OPN)and osteocalcin(OCN),and the formation of mineralized nodules,and the application of the p3. signaling pathway inhibitor SB203.80 vitiated the osteogenesis-promoting effect of ***:Immunocytochemical staining showed that the cells were Vimentin and Six2(+),E-cadherin and CK-18(−).Naringin can activate the p3. signaling pathway to enhance the osteogenesis of porcine MMCs by increasing cell viability,ALP activity,the expressions of Runx2,OPN and OCN,and the formation of mineralized nodules(P3. signaling pathway inhibitor SB203.80 vitiated the osteogenesis-promoting effect of naringin,manifested by decreased ALP activity,the expressions of Runx2,OPN and OCN,and the formation of mineralized nodules(Pchinese herbal medicine Rhizoma Drynariae for nourishing Shen(Kidney)and strengthening bone,enhances the osteogenic differentiation of renal MMCs through the p3. signaling pathway.

关键词： metanephric mesenchymal cells naringin osteogenesis differentiation

Evaluation of molecular residual disease in operable non-small cell lung cancer with gene fusions,MET exon skipping or de novo MET amplification

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Frontiers of Medicine 2024年第4期18卷 735-743页

作者： Rui fu Yuanyuan Xiong Miao Cai Fang Li Rongrong chen Yilong Wu Wenzhao Zhong School of Medicine South China University of TechnologyGuangzhou510006China Guangdong Lung Cancer institute Guangdong Provincial Key Laboratory of Translational Medicine in Lung CancerGuangdong Provincial People’s Hospital(Guangdong Academy of Medical Sciences)Southern Medical UniversityGuangzhou510080China Geneplus-Beijing Beijing102206China

Gene fusions and MET alterations are rare and difficult to detect in plasma *** clinical detection efficacy of molecular residual disease(MRD)based on circulating tumor DNA(ctDNA)in patients with non-small cell lung cancer(NSCLC)with these mutations remains *** prospective,non-intervention study recruited 49 patients with operable NSCLC with actionable gene fusions(ALK,ROS1,RET,and FGFR1),MET exon 14 skipping or de novo MET *** analyzed 43.tumor tissues and 111 serial perioperative plasma samples using 1021-and 3.8-gene panels,*** MRD correlated with a significantly higher recurrence rate(Pfusion/MET alterations in their MRD had reduced DFS compared to those who did not(P=0.05).To our knowledge,this is the first comprehensive study on ctDNA-MRD clinical detection efficacy in operable NSCLC patients with gene fusions and MET *** with detectable tissue-derived fusion/MET alterations in postoperative MRD had worse clinical outcomes.

关键词： ctDNA molecular residual disease operable NSCLC gene fusion MET exon skipping MET amplification

Synthesis of Methylated β-Cyclodextrins Derived Optically Active Poly(N-diphenylmethyl maleimide)

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chinese Chemical Letters 1997年第3期8卷 215-218页

作者： Wei Hong LIU Yong Ming chen Chuan fu chen and fu XI (institute of Chemistry,{3., Beijing 100080 ) chinese ACAD SCI INST CHEMBEIJING 100080PEOPLES R CHINA

The methylated β-cyclodextrins derived optically active polymers are firs synthesized through asymmetric polymerization of N-diphenylmethyl maleimide with lithium salt of heptakis(2,6-O-dimethyl) β-cyclodextrin (DM-β-CD) as an initiator. The resulting polymers show negative specific rotation which is opposite in sign to that of DM-β-CD. The asymmetric induction is further confirmed by circular dichroism. The structure is characterized by IR and NMR spectroscopies

关键词： Cyclodextrins Derived Optically Active Poly Li chen N-diphenylmethyl maleimide Synthesis of Methylated

A THEORETICAL APPROACH TO P_(co_2) EVOLUTION IN THE ATMOSPHERE BASED ON ASSOCIATIONS OF SEDIMENTARY MINERALS

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Science China Chemistry 1989年第12期32卷 1509-1519页

作者：陈福朱笑青 institute of geochemistry Academia Sinica. Guiyang 550002 PRC

Based on the theory of pH evolution of sea water and the balance between the seawater and the atmosphere the authors discussed the problems about (i) the method ofcalculating P_(CO_2) in the ancient atmosphere with the associations of sedimentary miner-als; (ii) the evolution of P_(CO_2) values in the geologic history; (iii) the relations of thepH evolution of sea water with carbonate precipitations; and (iv) calculation of the pHlimit for some associations of sedimentary minerals and its corresponding P_(CO_2) valuesin the atmosphere. The authors pointed out that though carbonates had deposited little in the Archaean,the content of CO_2 gas in the Archaean atmosphere was very high and was gradually go-ing up to form a thick CO_2 atmosphere. Up to 2600 Ma ago, the P_(CO_2) had reached a gradeof 10- 50 atm. There was a general trend of evolution that from the early Proterozoicera to the present the depositional horizon of carbonate layers was gradually risingand finally surpassed the horizons of clay minerals and sulfides. The corresponding P_(CO_2)in the atmosphere was lowering from the thick CO_2 atmosphere to the present 0.03.atm. On the basis of the calculated P_(CO_2) sizes and its fluctuation characteristics thehistory of P_(CO_2) evolution can be divided into three major stages.

关键词： changes of sedimentary minerals pH conditions of carbonate precipitation evolution of P_(co_2) in the atmosphere