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Chinese Journal of Structural Chemistry 2010年第7期29卷 1115-1121页

作者： jin xin tang li-ming you hu Laboratory of Advanced Materials Department of Chemical Engineering Tsinghua University Beijing 100084 China

Three secondary amine terminated hyperbranched poly（ester-amine）s （defined as HPEA1, HPEA2 and HPEA3） were synthesized from piperazine （A2） and trimethylolpropane triacrylate （TMPTA, B3） at their molar ratios of 2.5：1, 2.25：1 and 2.0：1, respectively. The polymers were analyzed by 1H NMR, GPC, DSC and TGA. The results indicated that the ratio of secondary amine to tertiary amine and the content of secondary amine decreased, while the molecular weight, molecular weight distribution and glass transition temperature （Tg） increased from HPEA1 to HPEA3. Due to their reactive terminal groups and flexible chains, these polymers further reacted with an epoxy resin （E51） to form cured films under ambient conditions. With increasing the ratio between secondary amine groups and epoxy groups from 1：2 to 2：1, the gel content, film hardness and onset decomposing temperature of the cured samples increased. The good film performances should make the polymers as the components of non-solvent coating materials.

关键词： hyperbranched poly(ester-amine) structure epoxy resin curing film

P-and SV-wave dispersion and attenuation in saturated microcracked porous rock with aligned penny-shaped fractures

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Petroleum Science 2024年第1期21卷 143-161页

作者： Sheng-Qing li Wen-Hao Wang Yuan-Da Su Jun-xin Guo Xiao-ming tang School of Geosciences China University of Petroleum(East China)Qingdao 266580ShandongChina Laoshan National Laboratory Qingdao 266071ShangdongChina Guangdong Provincial Key Laboratory of Geophysical High-resolution Imaging Technology Southern University of Science and TechnologyShenzhen 518055GuangdongChina Department of Earth and Space Sciences Southern University of Science and TechnologyShenzhen 518055GuangdongChina

P-and SV-wave dispersion and attenuation have been extensively investigated in saturated poroelastic media with aligned ***,there are few existing models that incorporate the multiple wave attenuation mechanisms from the microscopic scale to the macroscopic ***,in this work,we developed a unified model to incorporate the wave attenuation mechanisms at different scales,which includes the microscopic squirt flow between the microcracks and pores,the mesoscopic wave-induced fluid flow between fractures and background(FB-WIFF),and the macroscopic Biot's global flow and elastic scattering(ES)from the *** tang's modified Biot's theory and the mixed-boundary conditions,we derived the exact frequency-dependent solutions of the scattering problem for a single penny-shaped fracture with oblique incident P-and *** then developed theoretical models for a set of aligned fractures and randomly oriented fractures using the Foldy *** results indicated that microcrack squirt flow considerably influences the dispersion and attenuation of P-and SV-wave *** coupling effects of microcrack squirt flow with the FB-WIFF and ES of fractures cause much higher velocity dispersion and attenuation for P waves than for SV *** oriented fractures substantially reduce the attenuation caused by the FB-WIFF and ES,particularly for the ES attenuation of SV *** a comparison with existing models in the limiting cases and previous experimental measurements,we validated our model.

关键词： Aligned fractures P-and SV-wave Dispersion and attenuation Microcracked porous background FB-WIFF Elastic scattering Squirt flow

Hollow-structured all-silicon terahertz metasurface supporting quasi-bound states in the continuum for refractive index based Auramine O concentration sensing

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Photonics Research 2024年第7期12卷 1574-1582页

作者： xin tang HAODUO JIA LANBIN li ming li DAI WU KUI ZHOU PENG li WEIJUN WANG JITAO li DINGYU YANG College of Optoelectronic Engineering Chengdu University of Information TechnologyChengdu 610225China Institute of Applied Electronics China Academy of Engineering PhysicsMianyang 621000China School of Precision Instruments and Opto-Electronics Engineering Tianjin UniversityTianjin 300072China Guizhou Zhenhua Fengguang Semiconductor Co. Ltd.Guiyang 550000China Chengdu huanyuxin Technology Co. Ltd.Chengdu 610095China

Quasi-bound states in the continuum (QBIC),with exceptionally high-Q factors and the local field enhancement effect,have found potential applications in matter *** the QBIC mechanism into terahertz(THz) metasurfaces can significantly enhance the interaction between incident THz waves and matter,providing a feasible platform for the detection of biochemical ***,most experimental studies on terahertz QBIC metasurfaces utilize metallic *** contrast,research on terahertz all-dielectric QBIC metasurfaces generally remains at the simulation stage due to the high fabrication process requirements,and transitioning to the experimental stage still poses many *** this paper,a hollow-structured all-silicon metasurface supporting THz QBIC is *** resonance of THz QBIC is excited via a simple hollow structure and observed in *** and experimental results demonstrated that the designed THz QBIC metasurface can achieve sensing of Auramine ***,it is the first study,to our knowledge,to employ a metasurface to sense Auramine ***,the sensing performance maintains good stability under different humidity and temperature *** study provides new references and insights for the design and implementation of THz QBIC,and also opens a new pathway for the detection of Auramine O.

关键词： supporting continuum refractive

Electrochemical chemoselective thiocarbamylation of late-stage Tyr-containing drugs and peptides

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Science China Chemistry 2024年第10期67卷 3382-3388页

作者： Wan-Jie Wei xin-Yu Wang Hai-Tao tang Fei-hu Cui Yun-Qi Wu Ying-ming Pan State Key Laboratory for Chemistry and Molecular Engineering of Medicinal Resources Key Laboratory for Chemistry and Molecular Engineering of Medicinal Resources(Ministry of Education of China)Collaborative Innovation Center for Guangxi Ethnic MedicineSchool of Chemistry and Pharmaceutical SciencesGuangxi Normal UniversityGuilin 541004China

The synthesis and modification of peptides occupy a unique position in the field of drug development,and the functionalization of amino acids is a valuable strategy as an alternative to peptide ***,the development of tyrosine(Tyr)as a target amino acid is a major challenge in the field of ***,we report an electrochemical radical coupling reaction of labeling tyrosine-containing active drugs and peptides with thiocarbamate derivatives for the first *** tri-component,onepot reaction can be performed smoothly under simple,gentle,and clean electrochemical conditions and is suitable for the functionalization of various Tyr-containing drug molecular derivatives and peptides.

关键词： tyrosine electrochemical radical coupling chemical modification peptides

Arbuscular mycorrhizal fungi inoculation and exogenous indole-3-acetic acid application induce antioxidant defense response to alleviate cadmium toxicity in Broussonetia papyrifera

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Pedosphere 2024年第2期34卷 447-459页

作者： Xue li jingwei liANG Hongjian WEI Yuxuan KUANG hui CHEN ming tang Wentao hu State Key Laboratory of Conservation and Utilization of Subtropical Agro-Bioresources Guangdong Laboratory for Lingnan Modern AgricultureGuangdong Key Laboratory for Innovative Development and Utilization of Forest Plant GermplasmCollege of Forestry and Landscape ArchitectureSouth China Agricultural UniversityGuangzhou 510642China

Cadmium(Cd)contamination in soil poses a huge threat to plants even at low concentrations;Broussonetia papyrifera has great potential in remediation of soil heavy metal ***,whether exogenous indole-3-acetic acid(IAA)application and arbuscular mycorrhizal fungi(AMF)have synergistic effects on Cd tolerance of *** remains *** investigate the effects of AMF inoculation and IAA application on the tolerance of *** to Cd stress,two experiments were conducted:the first to investigate the effect of AMF(Rhizophagus irregularis)inoculation on the tolerance of *** to Cd stress and the second to investigate the combined effects of AMF inoculation and IAA application on the tolerance of *** to Cd *** including endogenous hormone concentration,antioxidant defense response,malondialdehyde(MDA)content,and gene expression related to antioxidant enzyme system and hormone were *** results indicated that AMF alleviated Cd toxicity of *** by reducing MDA content and improving antioxidant enzyme activities and Cd absorption ***,the combination of AMF inoculation and IAA application had a synergetic effect on the tolerance of *** to Cd stress through upregulating BpAUX1 and BpAUX2,which might contribute to root growth and root xylem synthesis,and by upregulating BpSOD2 and BpPOD34 to enhance the antioxidant enzyme *** work provides a new insight into the application of IAA in the remediation of soil Cd pollution by mycorrhizal plants.

关键词： enzyme activity geneexpression heavy metal phytoremediation remediation Rhizophagus irregularis soil cadmium pollution stress tolerance

Development of Ti–V–Cr–Mn–Mo–Ce high-entropy alloys for high-density hydrogen storage in water bath environments

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Rare Metals 2024年第10期43卷 5229-5241页

作者： hua-Zhou hu Hou-Qun Xiao xin-Cong He Wen-Hao Zhou Xiao-Xuan Zhang Rui-Zhu tang Jie li Chuan-ming Ma Qing-Jun Chen Key Laboratory of Rare Earths Chinese Academy of SciencesJiangxi Institute of Rare EarthsGanjiang Innovation AcademyChinese Academy of Sciences

The V-based body-centered cubic （BCC）-type hydrogen storage alloys have attracted significant attention due to their high theoretical hydrogen storage capacity of3.80 wt%.However,their practical application faces challenges related to low dehydriding capacity and poor activation *** overcome these challenges,a BCC-type Ti–V–Cr–Mn–Mo–Ce high-entropy alloy（HEA） with an effectively dehydriding capacity of 2.5 wt% above 0.1 MPa was *** introduction of Mo and conducting heat treatment,the precipitation of Ti-rich phase in HEA was successfully suppressed,resulting in improved compositional uniformity and dehydriding ***,the effective dehydriding capacity increased significantly from 0.60 wt% to 2.50 wt% a65℃,surpassing that of other types of hydrogen storage alloys under the same ***,the addition of 1 wt%Ce enabled initial hydrogen absorption at 25℃ without the need for activation at 400℃.Furthermore,Ce doping reduced the dehydriding activation energy of the Ti–V–Cr–Mn–Mo–Ce HEA from 52.71 to 42.82 kJ·mol-1Additionally,the enthalpy value of dehydrogenation decreased from 46.89 to 17.96 k J·mol-1,attributed to a decrease in the hysteresis factor from 0.68 to *** findings provide valuable insights for optimizing the hydrogen storage property of HEA.

关键词： BCC structure Ce doping Heat treatment High-entropy alloys Hydrogen storage alloys

Two-dimensional bimetallic selenium-containing metal-organic frameworks and their calcinated derivatives as electrocatalysts for overall water splitting

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Frontiers in Energy 2024年第3期18卷 378-389页

作者： Zhao-ting SHANG tang-ming li Bing-qian hu Min liU Wang-ting LU Fan YU Yun ZHENG Key Laboratory of Optoelectronic Chemical Materials and Devices of Ministry of Education College of Optoelectronic Materials and TechnologyJianghan UniversityWuhan 430056China Institute of New Energy Materials and Engineering School of Materials Science and EngineeringFuzhou UniversityFuzhou 350108China Department of Chemical Engineering University of WaterlooWaterlooOntario N2L 3G1Canada

The use of two-dimensional(2D)layered metal-organic frameworks(MOFs)as self-sacrificial templates has been proven to be a successful method to create high-efficiency Selenium(Se)-containing electrocatalysts for overall water ***,two strategies are then utilized to introduce Se element into the Co–Fe MOF,one being the etching of as-prepared MOF by SeO_(2) solution,and the other,the replacing of SCN−with SeCN−as the construction *** electrochemical activity of the pristine 2D MOF and their calcinated derivatives for catalyzing the hydrogen evolution reaction(HER)and oxygen evolution reaction(OER)is evaluated and further *** is found that the effect of introducing Se on improving electrochemical catalytic activity is significant for the HER ***,the calcinated derivative in the replacing method exhibits an overpotential of 235 mV for HER and 270 mV for OER at a current density of 10 mA/*** comparing the two methods of introducing Se element into MOF,similar electrocatalytic activity can be achieved on the their calcinated *** high electrochemical performance of 2D CoFe-MOF derivatives may be resulted from the unique 2D hierarchical porous structure and strong synergistic effect between different components in the material.

关键词： 2D MOF selenium(Se)-containing materials hydrogen evolution reaction(HER) oxygen evolution reaction(OER)

Thickening progression mechanism of silica fume-oil well cement composite system at high temperatures

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Petroleum Science 2024年第4期21卷 2793-2805页

作者： Hang Zhang Miao-Miao hu Peng-Peng li Guo-Qing liu Qing-Lu Chang Jie Cao ming liu Wen-hua Xu Xiu-Jian Xia jin-tang Guo School of Chemical Engineering and Technology Tianjin University Zhejiang Institute of Tianjin University Haihe Laboratory of Sustainable Chemical Transformations CNPC Engineering Technology R&D Company limited

This work studied the thickening progression mechanism of the silica fume-oil well cement composite system at high temperatures(110-180.C) in order to provide a theoretical guidance for the rational application of silica fume in the cementing engineering. Results showed that silica fume seldom affected the thickening progression of oil well cement slurry at 110-120.C, but when temperature reached above130.C, it would aggravate the bulging degree of thickening curves and significantly extend the thickening time, meanwhile causing the abnormal “temperature-based thickening time reversal” and“dosage-based thickening time reversal” phenomena in the range of 130-160.C and 170-180.C respectively. At 130-160.C, the thickening time of oil well cement slurry was mainly associated with the generation rate of calcium hydroxide(CH) crystal. The introduced silica fume would be attracted to the cement minerals' surface that were hydrating to produce CH and agglomerate together to form an“adsorptive barrier” to hinder further hydration of the inner cement minerals. This “adsorptive barrier”effect strengthened with the rising temperature which extended the thickening time and caused the occurrence of the “temperature-based thickening time reversal” phenomenon. At 170-180.C, the pozzolanic activity of silica fume significantly enhanced and considerable amount of C-S-H was generated, thus the “temperature-based thickening time reversal” vanished and the “dosage-based thickening time reversal” was presented.

关键词： Silica fume Oil well cement Thickening time reversal Pozzolanic reaction Adsorptive barrier CH and C−S−H

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

Metal-Free,Site-Selective C-H Fluorination of Heteroarenes Under Visible light

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CCS Chemistry 2024年第7期6卷 1681-1688页

作者： Cheng huang Chang-ming you Yu-Shu Qin Rui-Nan Ci Peng Xiao Sheng tang Bin liu Zhenhong Wei li-Zhu Wu hu Cai School of Chemistry and Chemical Engineering Nanchang UniversityNanchangJiangxi 330031 Key Laboratory of Photochemical Conversion and Optoelectronic Materials Technical Institute of Physics and ChemistryUniversity of Chinese Academy of SciencesChinese Academy of SciencesBeijing 100190 School of Future Technology University of Chinese Academy of SciencesBeijing 100049

The site-selective C-H fluorination of heteroarenes is a straightforward approach to accessing valuable heteroaryl fluorides but remains a formidable ***,we report a general strategy for visible-light-induced C-H fluorination of heteroarenes via the merger of N-F fluorinating reagents and *** paramagnetic resonance experiments provide evidence for the homolytic cleavage of the N-F bond under blue light-emitting diode irradiation,which is the key step in the *** transformation is metal-free,photocatalysts-free,and site-selective under mild reaction conditions(ambient temperature,visible-light irradiation,tolerant to H2O).The robustness of this protocol has also been highlighted by late-stage modification of complex and medicinally relevant molecules.

关键词： selective C-H fluorination heteroaryl fluorides C(sp^(2))-F bond formation photochemistry radical chemistry