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New speckle pattern interferometry for precise in situ deformation measurements

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Chinese Optics Letters 2024年第1期22卷 34-40页

作者：章如月 yu fu 缪泓 CAS Key Laboratory of Mechanical Behavior and Design of Materials Department of Modern MechanicsUniversity of Science and Technology of ChinaHefei 230027China Shenzhen Key Laboratory of Intelligent Optical Measurement and Detection College of Physics and Optoelectronic EngineeringShenzhen UniversityShenzhen 518060China

A new electronic speckle pattern interferometry method is proposed to realize in situ deformation *** feature of the method is the combination of a high-speed camera and multiple laser Doppler vibrometers(LDVs)for synchronous *** high-speed camera is used to record and select effective interferograms,while the LDVs are used to measure the rigid body displacement caused by vibrations.A series of effective interferograms with known shifted phase values are obtained to calculate the deformation *** experimental results show that the method performs well in measuring static and dynamic deformations with high accuracy in vibrating environments.

关键词： speckle pattern interferometry laser Doppler vibrometers in situ deformation measurements

Significantly Enhanced Melt Memory Effect of Metallocene-made Isotactic Polypropylene Containing Talc

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Chinese Journal of Polymer Science 2024年第2期42卷 213-222,I0008页

作者： Hong-Wen Sun fu-Shan Wang Yan Gao fu-Qing Wei Jia-chun Feng State Key Laboratory of Molecular Engineering of Polymers Department of Macromolecular ScienceFudan UniversityShanghai200433China Lanzhou Petrochemical Corporation of PetroChina Lanzhou730060China Lanzhou Petrochemical Research Center Petrochemical Research Institute of PetroChinaLanzhou730060China

The melt memory effect is a widely observed phenomenon in semi-crystalline polymers. In practical applications, various additives are usually introduced into polymers, which may affect their melt memory behavior. In this work, the effect of talc on the melt memory effect of metallocene-made isotactic polypropylene(M-PP) was investigated in detail by using the differential scanning calorimetry. The results indicated that the introduction of talc significantly strengthened the melt memory effect of M-PP. Specifically, the upper limit temperature of Domain II increased from 161 ℃ to 174 ℃, resulting in a substantial widening of the temperature range of Domain IIa from 1 ℃ to 14 ℃. Analysis of the crystal orientation of the M-PP containing talc cooled from various Ts suggested that the remarkably enhanced melt memory effect could be ascribed to the stabilization of oriented nuclei facilitated by talc. This stabilizing effect was likely attributable to the prefreezing effect or the sorption interaction between talc and the M-PP chains.

关键词： Metallocene-made isotactic polypropylene Talc Melt memory effect Crystal orientation

Machine learning-based predictions of current and future susceptibility to retrogressive thaw slumps across the Northern Hemisphere

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Advances in Climate Change Research 2024年第2期15卷 253-264页

作者： Jing LUO Guo-An YIN fu-Jun NIU Tian-chun DONG Ze-Yong GAO Ming-Hao LIU Fan yu State Key Laboratory of Frozen Soil Engineering Northwest Institute of Eco-Environment and ResourcesChinese Academy of SciencesLanzhou 730000China China Railway Qinghai-Tibet Group Co. LtdXining 810000China University of Chinese Academy of Sciences Beijing 100049China

Retrogressive thaw slumps(RTSs)caused by the thawing of ground ice on permafrost slopes have dramatically increased and become a common permafrost hazard across the Northern Hemisphere during previous ***,a gap remains in our comprehensive understanding of the spatial controlling factors,including the climate and terrain,that are conducive to these RTSs at a global *** machine learning methodologies,we mapped the current and future RTSs susceptibility distributions by incorporating a range of environmental factors and RTSs *** identified freezing-degree days and maximum summer rainfall as the primary environmental factors affecting RTSs *** final ensemble susceptibility map suggests that regions with high to very high susceptibility could constitute(11.6±0.78)%of the Northern Hemisphere's permafrost *** juxtaposed with the current(2000-2020)RTSs susceptibility map,the total area with high to very high susceptibility could witness an increase ranging from(31.7±0.65)%(SSP585)to(51.9±0.73)%(SSP126)by the *** insights gleaned from this study not only offer valuable implications for engineering applications across the Northern Hemisphere,but also provide a long-term insight into the potential change of RTSs in permafrost regions in response to climate change.

关键词： Retrogressive thaw slump Machine learning Susceptibility map Permafrost Northern Hemisphere

Elastic three-dimensional phononic topological insulators with Dirac hierarchy

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Science China(Physics,Mechanics & Astronomy) 2024年第5期67卷 54-62页

作者： Shao-Yong Huo Qiu-Shuang Yang Jiu-Jiu Chen Hong-Kang Li Long-Chao Yao fu-chun He chun-Ming fu College of Mechanical Engineering University of South ChinaHengyang 421001China State Key Laboratory of Advanced Design and Manufacturing for Vehicle Body College of Mechanical and Vehicle EngineeringHunan UniversityChangsha 410082China

Three-dimensional(3D)phononic topological insulators(TIs)featuring two-dimensional(2D)surface states and one-dimensional(1D)hinge states have opened up a new route for multi-dimensional robust wave transport,providing unprecedented methods for integrated acoustic sensors and energy harvesting ***,aiming at the elastic 3D phononic TI with gapless surface states and hinge states,the realization of elastic 3D phononic TIs with gapless surface states and hinge states is a significant challenge due to the complicated multi-mode polarization of elastic waves in 3D *** this study,we demonstrate an elastic 3D phononic TI with a Dirac hierarchy by elaborately operating the corresponding spatial symmetries of the chiral honeycomb ***,a 3D double Dirac cone of elastic wave can be achieved by doubling the lattice along the outof-plane direction to fold two iso-frequency Weyl *** topological phase transitions and 2D gapless two-fold Dirac surface states of elastic wave are realized by breaking the half-lattice spatial translation ***,based on the Brillouin zone folding along the in-plane direction,the 2D gapless two-fold surface Dirac cones are folded into four-fold surface Dirac ***,by inducing the relative radius of adjacent holes to break the in-plane spatial inversion symmetry,the fourfold surface Dirac cones are gapped and associated with a surface state inversion,in which the gapless 1D hinge Dirac dispersion is *** research offers a route for engineering the hierarchies of TIs in 3D elastic wave systems and provides new possibilities for designing 3D ultrasonic devices with unconventional functions.

关键词： Dirac topological hierarchy

Electronic structure regulation and built-in electric field synergistically strengthen photocatalytic nitrogen fixation performance on Ti-BiOBr/TiO_(2)heterostructure

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Rare Metals 2024年第3期43卷 1125-1138页

作者： Ru-Qi Li yu-Jie Bian chun-Ming Yang Li Guo Tao-Xia Ma Chuan-Tao Wang Feng fu Dan-Jun Wang College of Chemistry and Chemical Engineering Yan’an UniversityYan’an Key Laboratory of Green Catalysis and Quality Improvement and Utilization of Low Rank CoalYan’an716000China

At present,industrial synthetic ammonia was still obtained through the Hubble-Bosch process,with large energy *** is a research hotspot to realize green synthetic ammonia by using solar *** difficulty of photocatalytic ammonia synthesis was that the photo-excited electrons have not enough energy to active N≡*** this study,Ti was doped into BiOBr by one-step hydrothermal method,which was oxidized into TiO_(2)when the doping amount reaches the maximum,in situ forming Ti_(0.31)B_(0.69)OB/TiO_(2)*** from the synergistic effect of Ti doping and S-scheme heterojunction,the synthetic ammonia efficiency of Ti_(0.31)B_(0.69)OB/TiO_(2)-11.96 reached 1.643 mmol·g_(cat)^(-1)at mild conditions and without hole scavenger for up to 7 h,the efficiency of synthetic ammonia is 115 times,10.5 times and 3.3 times of that of BiOBr,Ti_(0.31)B_(0.69)OB and TiO_(2),***,DFT calculation confirms that Ti doping accurately refine the electronic structure of BiOBr,facilitate nitrogen adsorption activation and reduce hydrogenation reaction energy barrier,thus accelerating the reaction kinetics of photocatalytic nitrogen reduction(NRR),Meanwhile,constructing S-scheme heterojunction boosts the separation and transfer of photogenerated electron-hole pairs,improving the reduction ability of electrons in the conduction band of TiO_(2)and the oxidation ability of holes in the valence band of Ti_(0.31)B_(0.69)OB.

关键词： S-scheme heterostructure Electronic structure regulation Built-in electric field Synergistical stren4gthening Photocatalytic nitrogen fixation

Proteomics Study of Benzene Metabolite Hydroquinone Induced Hematotoxicity in K562 Cells

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Biomedical and Environmental Sciences 2024年第4期37卷 341-353页

作者： JIN Yi Shan YI Zong chun ZHANG yu Jing RONG Long yu chun Hong School of Biological Science and Medical Engineering Beihang UniversityBeijing 100191China School of Engineering Medicine Beihang UniversityBeijing 100191China

Objective Hydroquinone(HQ),one of the phenolic metabolites of benzene,is widely recognized as an important participant in benzene-induced ***,there are few relevant proteomics in HQ-induced hematotoxicity and the mechanism hasn’t been fully understood *** In this study,we treated K562 cells with 40μmol/L HQ for 72 h,examined and validated protein expression changes by Label-free proteomic analysis and Parallel reaction monitoring(PRM),and performed bioinformatics analysis to identify interaction *** One hundred and eighty-seven upregulated differentially expressed proteins(DEPs)and 279 downregulated DEPs were identified in HQ-exposed K562 cells,which were involved in neutrophilmediated immunity,blood microparticle,and other GO terms,as well as the lysosome,metabolic,cell cycle,and cellular senescence-related *** on the 23 DEGs and 5 DEPs in erythroid differentiation-related pathways,we constructed the network of protein interactions and determined 6 DEPs(STAT1,STAT3,CASP3,KIT,STAT5B,and VEGFA)as main hub proteins with the most interactions,among which STATs made a central impact and may be potential biomarkers of HQ-induced *** Our work reinforced the use of proteomics and bioinformatic approaches to advance knowledge on molecular mechanisms of HQ-induced hematotoxicity at the protein level and provide a valuable basis for further clarification.

关键词： Hydroquinone Proteomics Hematotoxicity K562 cells

Studies on NaXe Clusters

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Chinese Chemical Letters 2001年第9期12卷 833-834页

作者： Jia Chang LIANG Zhi LIU Yi Min SHEN Xian Ping SUN Xi Zi ZENG Xiao yun LE Xiang yun WANG De Min WANG fu chun yu Yong Ti CHEN College of sciences Civil Aviation Institute of ChinaTianjin 300300 Department of Chemistry Nankai UniversityTianjin 300071 Department of Radiology Wayne State UniversityDetroit MI 48201 USA Laboratory of Magnetic Resonance and Atomic and Molecular Physics Wuhan Institute of Phys.&Math.The Chincse Academy of SciencesWuhan 430071 Institute of Heavy lon Physics Peking UniversityBeijing 100871

The chemical shift of Na-23 in excimer NaXe was measured by using nuclear magnetic resonance (NMR) spectra, which is in good agreement with the theoretical value obtained by ab initio calculations. The bond length, dissociation energy, dipole of NaXe and Mulliken charges at Na and Xe in NaXe were calculated, respectively. The spectra of ultraviolet (UV) fluorescence and surface-enhanced Raman scattering of NaXe were also measured.

关键词： Xenon-ion-implanted NaCl crystal NaXe chemical shift ab initio calculation

Evolution of copper species during heat treatment and its effect on CO oxidation reaction on CuCeZrO_(y) catalyst synthesized by a facile solvent-free route

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Journal of Rare Earths 2024年第4期42卷 660-667页

作者： Guangying fu Dongsen Mao Jun yu Qiangsheng Guo School of Chemical and Environmental Engineering Shanghai Institute of TechnologyShanghai21418 China The ZeoMat Group Qingdao Institute of Bioenergy and Bioprocess TechnologyCASQingdao26611China

Several ternary oxides CuCeZrO_(y)(CCZ)were synthesized by a facile grinding method followed by calcination at high temperatures,and used as catalysts for CO oxidation at low *** influences of calcination temperature(400-600℃)on the physicochemical properties of the assynthesized ternary oxides were investigated by thermogravimetric analysis/differential scanning calorimetry(TGA/DSC),X-ray diffraction(XRD),transmission electron microscopy(TEM),Raman,inductively coupled plasma-optical emission spectrometry(ICP-OES),N_(2) adsorption,H_(2)-temperature programmed reduction(H_(2)-TPR),and X-ray photoelectron spectroscopy(XPS)*** results show that the increase in calcination temperature from 400 to 500℃is conducive to the high dispersion of CuOx on catalyst surface and the incorporation of Cu species into the support to form the Cu-Ce-Zr-O solid *** raising of calcination temperature from 500 to 600℃,however,leads to the segregation of Cu species from the solid solution to aggregate on support surface and growth of highly dispersed CuOx *** highest catalytic activity is acquired over the CCZ calcined at 500℃,which can be ascribed to the largest contents of Cu+species and oxygen vacancies owing to the formation of the maximum amount of Cu-Ce-Zr-O solid solution.

关键词： CuCeZrO_(y)catalyst co oxidation Calcination temperature Grinding method Oxalate precursor Rare earths

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考虑空间整体效应的温度自应力计算

铁道学报 2007年第6期29卷 80-83页

作者：付春雨李乔西南交通大学土木工程学院四川成都610031

针对在计算混凝土桥梁结构的温度自应力时,按现行的计算方法得到的结果与实测的数据有较大差别的问题,根据温度作用下的应力-应变关系及结构内力特点,并运用三维平面假设,改变温度荷载的加载方式和多余约束力的状态,推导出考虑空间整体... 详细信息

针对在计算混凝土桥梁结构的温度自应力时,按现行的计算方法得到的结果与实测的数据有较大差别的问题,根据温度作用下的应力-应变关系及结构内力特点,并运用三维平面假设,改变温度荷载的加载方式和多余约束力的状态,推导出考虑空间整体效应的温度自应力计算方法。对箱梁的实例分析表明:在计算桥梁结构的温度自约束应力时,应考虑纵横向温度应力-应变之间的互相影响,采用与实际情况相符合的温度荷载加载方式,这样使计算结果更接近实际值。

关键词：桥梁工程温度自约束应力弹性力学三维模型非线性温度荷载