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Effect of coordination structure of aluminum on its activation from minerals and Oxisols during their acidification

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Pedosphere 2024年第5期34卷 916-928页

作者： Kewei LI Yangxiaoxiao SHI Jackson Nkoh NKOH jun jiang Renkou XU State Key Laboratory of Soil and Sustainable Agriculture Institute of Soil Science Chinese Academy of Sciences University of Chinese Academy of Sciences

The types and contents of phyllosilicate minerals in soils play an important role in soil acidification,as soil acid buffering capacity varies with the composition of the phyllosilicate *** addition to aluminum-oxygen （Al-O） octahedrons,a certain number of Al-O tetrahedrons exist in phyllosilicate minerals due to the isomorphic substitution of silicon ion (Si4+) by aluminum ion (Al3+) in Si-O tetrahedrons of ***,the effect of the two coordination structures of Al on the release of Al during mineral acidification has not yet been ***,the differences in Al activation in phyllosilicate minerals and soils with different Al coordination structures were investigated through constant-p H experiments and27Al magic-angle spinning nuclear magnetic resonance （MAS-NMR） *** results of27Al MAS-NMR spectra showed that kaolinite contained Al-O octahedrons,phlogopite and illite contained Al-O tetrahedrons,and vermiculite composite contained both octahedral and tetrahedral *** p Hvermiculite composite>phlogopite>kaolinite,which was consistent with the orders of cation exchange capacity and content of tetrahedral Al of the *** to the rate constants,the Al release rates were in the order of phlogopite>illite>vermiculite composite>kaolinite at p H *** for phlogopite,the Al release rates in these minerals increased with decreasing suspension p ***,the Al release contents and rates were greater in phlogopite,illite,and vermiculite composite containing Al-O tetrahedrons than in kaolinite containing only Al-O *** Oxisols derived from basalt with different ages were selected for similar ***27Al MAS-NMR spectra of the Oxisols showed that the 0.01-million-year （Ma） Oxisol contained both octahedral and tetrahedral Al,while the 1.33-Ma Oxisol contained only Al-O *** contents of b

关键词： Al-O octahedrons Al-O tetrahedrons aluminum release exchangeable Al phyllosilicate minerals soil acidification

Microstructure and texture evolution of Cu-Cr-Co-Ti alloys during the two-stage cryorolling

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Rare Metals 2024年第9期43卷 4535-4547页

作者： Jia-jun Zhang Long-Jian Li Zhi-Feng Liu Zong-ning Chen En-Yu Guo Hui-jun Kang Ren-Geng Li Tong-Min Wang Key Laboratory of Solidification Control and Digital Preparation Technology(Liaoning Province) School of Materials Science and EngineeringDalian University of TechnologyDalian 116024China Center of Hyper-Gravity Experimental and Interdisciplinary Research Zhejiang UniversityHangzhou 310058China ningbo Institute of Dalian University of Technology Ningbo 315000China Key Laboratory for Light-Weight Materials Nanjing Tech UniversityNanjing 210009China

This study entailed an investigation of the mechanical properties,microstructural and texture orientation evolutions of Cu-Cr-Co-Ti alloys prepared via twostage cryorolling and intermediate aging *** this end,X-ray diffraction and electron backscatter diffraction were *** results indicate that the two-stage cryorolling and intermediate aging treatments led to the development of profuse twin bundles and significantly enhanced the mechanical *** initial cryorolling led to coplanar slip and developed a strong Y({111})orientation,accelerating the formation of Goss({011})orientation and a Brass-type *** intermediate aging treatment relieved the restriction on dislocation slip and reoriented the grains toward the Copper({112})and Z({111})*** Z orientation,with a relatively high volume fraction,dominated the *** cryorolling intensified twinning and shear banding,transforming the Copper-type shear bands into Brass-type shear bands with rhomboidal prism *** areas inside the Brasstype shear bands exhibited a Y orientation,and the areas outside the shear bands exhibited a stable Brass-type *** evident decrease in the weighted Schmid factors demonstrated that the two-stage cryorolling and intermediate aging treatment can modify the texture evolution and aid the design of high-performance Cu alloys.

关键词： Copper alloys Two-stage cryorolling Macrotexture evolution Electron backscatter diffraction Schmid factor

FPGA-based position reconstruction method for neutron beam flux spatial distribution measurement in BNCT

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Nuclear Science and Techniques 2024年第3期35卷 96-108页

作者： Wei jiang Ping Cao Yi-Ming Wu Xian-Ke Liu Zhu-jun Fang Zhi-Yong Zhang Bin Shi jun Chen State Key Laboratory of Particle Detection and Electronics University of Science and Technology of ChinaHefei 230026China Department of Modern Physics University of Science and Technology of ChinaHefei 230026China School of Nuclear Science and Technology University of Science and Technology of ChinaHefei 230026China National Key Laboratory for Metrology and Calibration Techniques China Institute of Atomic EnergyBeijing 102413China

A new measurement method for the spatial distribution of neutron beam flux in boron neutron capture therapy(BNCT)is being developed based on the two-dimensional Micromegas *** address the issue of long processing times in traditional offline position reconstruction methods,this paper proposes a field programmable gate array based online position reconstruction method utilizing the micro-time projection chamber *** method encapsulates key technical aspects:a self-adaptive serial link technique built upon the dynamical adjustment of the delay chain length,fast sorting,a coordinate-matching technique based on the mapping between signal timestamps and random access memory(RAM)addresses,and a precise start point-merging technique utilizing a circular combined *** performance test of the selfadaptive serial link shows that the bit error rate of the link is better than 10-12 at a confidence level of 99%,ensuring reliable data *** experiment utilizing the readout electronics and Micromegas detector shows a spatial resolution of approximately 1.4 mm,surpassing the current method’s resolution level of 5 *** beam experiment confirms that the readout electronics system can obtain the flux spatial distribution of neutron beams online,thus validating the feasibility of the position reconstruction *** online position reconstruction method avoids traditional methods,such as bubble sorting and traversal searching,simplifies the design of the logic firmware,and reduces the time complexity from O(n2)to O(n).This study contributes to the advancement in measuring neutron beam flux for BNCT.

关键词： Position reconstruction FPGA Readout electronics Neutron flux spatial distribution

Advances in selective conversion of carbohydrates into 5-hydroxymethylfurfural

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Green Energy & Environment 2024年第9期9卷 1384-1406页

作者： Jie Liang Jianchun jiang Tingting Cai Chao Liu jun Ye Xianhai Zeng Kui Wang Institute of Chemical Industry of Forest Products Chinese Academy of Forestry National Engineering Lab.for Biomass Chemical Utilization Co-Innovation Center of Efficient Processing and Utilization of Forest Resources Nanjing Forestry University College of Energy State Key Laboratory of Physical Chemistry of Solid Surfaces Xiamen University

Converting carbohydrates into 5-hydroxymethylfurfural(5-HMF) is an attractive and promising route for value-added utilization of agricultural and forestry biomass resource. As an important platform compound, 5-HMF possesses high active furan structure with hydroxymethyl and aldehyde group for production of various bio-chemicals and materials, meanwhile, which suffer from low stability and poor yield during the industrial biorefinery process. Hence, selective production of 5-HMF with high-yield and low-cost has attracted extensive attention from scientific and industrial researchers. This review sorted and described the latest advanced research on solvent and catalyst system, as well as energy field effect for production of 5-HMF with different feedstock in detail, emphatically discussing the solvent effect and its synergistic effect with other aspects. Besides, the future prospects and challenges for production of 5-HMF from carbohydrates were also presented, which provide a profound insight into industrial 5-HMF process with economic and environmental feature.

关键词： 5-Hydroxymethylfurfural Biorefinery Solvent Selectivity Carbohydrate

Spatiotemporal changes in sunshine duration and its influential factors in Chongqing,China from 1961 to 2020

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Journal of Mountain Science 2024年第6期21卷 2005-2024页

作者： LI jun XIA Hongxuan jiang Jinge XU Weifeng WEN Di XU junfeng College of Geography and Tourism Chongqing Normal UniversityChongqing 401331China Key Laboratory of GIS Application of Chongqing Chongqing 401331China Chongqing Key Laboratory of Earth Surface Processes and Environmental Remote Sensing in Three Gorges Reservoir area Chongqing 401331China Institute of Remote Sensing and Earth Sciences School of Institute of Remote Sensing and Earth SciencesSchool of ScienceHangzhou Normal UniversityHangzhou 311121China

The surface solar radiation in most parts of the world has undergone a phenomenon known as global dimming and brightening,characterized by an initial decrease followed by an *** a result,the sunshine duration(SD)has decreased in the past 60 *** the backdrop of global dimming and brightening,SD has decreased to varying degrees in many regions of *** the observed data of SD,cloud amount(total cloud amount and low cloud amount,abbreviated as TCA and LCA),precipitation,and relative humidity(RH)from 34 meteorological stations in Chongqing during the period of 1961-2020,along with a digital elevation model(DEM)with a resolution of 90 m,this study analyzed the spatiotemporal variations and influencing factors of *** analysis employed methods such as linear regression,Mann-Kendall test,wavelet transformation,and DEM-based possible SD distributed *** results showed that the annual SD in Chongqing has significantly decreased over the last 60 years,with a decreasing interannual trend rate(ITR)of 40.4 h/*** for no obvious trend in spring,SD decreased significantly in summer,autumn and winter at the ITR of 21.1 h/10a,8.5 h/10a and 7.5 h/10a,*** abrupt decrease in the annual SD was found in *** difference before and after the abrupt decrease was 177.7 *** difference before and after the abrupt decrease was 177.7 *** annual SD possessed the oscillation period of *** spatial heterogeneity of the mean annual SD during the last 60 years was *** distribution of SD in Chongqing is high in the northeast and low in the *** addition,about 73%of the total area in Chongqing showed a significant and very significant decreasing *** regions with significant changes are mainly concentrated in the regions with altitudes of 200~1000 *** increasing LCA was the main cause of the decrease of the annual SD in the regions with 200-400 m altitude decreased the most and changed the *** LCA is the prim

关键词： Sunshine duration Spatiotemporal changes Mann-Kendall test Wavelet analysis Geodetector model

Pathological diagnosis and immunohistochemical analysis of giant retrosternal goiter in the elderly: A case report

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World Journal of Clinical Cases 2024年第3期12卷 643-649页

作者： Yong-Chang Meng Liu-Sheng Wu ning Li Hong-Wei Li Jing Zhao jun Yan Xiao-Qiang Li Peng Li jiang-Qi Wei Department of Cardiothoracic Surgery Xinxiang First People's HospitalXinxiang 453000Henan ProvinceChina School of Clinical Medicine Tsinghua UniversityBeijing 100084China Graduate School Qinghai UniversityXining 810016Qinghai ProvinceChina Department of Pathology Xinxiang First People's HospitalXinxiang 453000Henan ProvinceChina Department of Thoracic Surgery Peking University Shenzhen HospitalShenzhen 518036Guangdong ProvinceChina

BACKGROUND Elderly giant retrosternal thyroid goiter is a rare yet significant medical condition,often presenting clinical symptoms that can be confused with other diseases,posing diagnostic and therapeutic *** study aims to delve into the characteristics and potential mechanisms of this ailment through pathological diagnosis and immunohistochemical analysis,providing clinicians with more precise diagnostic and treatment strategies.A 77-year-old male,was admitted to hospital with the chief complaint of finding a goiter in the semilunar month during physical examination,accompanied by *** protruding into the superior mediastinum,the adjacent structure was compressed,the trachea was compressed to the right,and the local lumen was slightly *** patient was diagnosed with giant retrosternal *** dyspnea caused by trachea compression,our department planned to perform giant retrosternal *** results:Tg(+),TTF-1(+),Calcitonin(CT)(I),Ki-67(+,about 20%),CD34(-).Retrosternal goiter means that more than 50%of the volume of the thyroid gland is below the upper margin of the *** retrosternal goiter disease is a relatively rare disease,once the disease is diagnosed,it should be timely surgical treatment,and the treatment is more difficult,the need for professional medical team for comprehensive *** The imaging manifestations of giant retrosternal goiter are atypical,histomorphology and immunohistochemistry can assist in its *** article reviews the relevant literature of giant retrosternal goiter immunohisto-chemistry and shows that giant retrosternal goiter is positive for Tg,TTF-1,and Ki-67.

关键词： Giant retrosternal goiter Pathology Immunohistochemistry Case report

Simulation study of the performance of the Very Large Area gamma-ray Space Telescope

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Nuclear Science and Techniques 2024年第9期35卷 1-17页

作者： Xu Pan Wei jiang Chuan Yue Shi-jun Lei Yu-Xin Cui Qiang Yuan Key Laboratory of Dark Matter and Space Astronomy Purple Mountain ObservatoryChinese Academy of SciencesNanjing 210023China School of Astronomy and Space Science University of Science and Technology of ChinaHefei 230026China

The Very Large Area gamma-ray Space Telescope(VLAST)is a mission concept proposed to detect gamma-ray photons through both Compton scattering and electron–positron pair production mechanisms,thus enabling the detection of photons with energies ranging from MeV to *** project aims to conduct a comprehensive survey of the gamma-ray sky from a low-Earth orbit using an anti-coincidence detector,a tracker detector that also serves as a low-energy calorimeter,and a high-energy imaging *** developed a Monte Carlo simulation application of the detector using the GEANT4 toolkit to evaluate the instrument performance,including the effective area,angular resolution,and energy resolution,and explored specific optimizations of the detector *** simulation-based analysis indicates that the current design of the VLAST is physically feasible,with an acceptance above 10 m^(2)sr which is four times larger than that of the Fermi-LAT,an energy resolution better than 2%at 10 GeV,and an angular resolution better than 0.2◦at 10 *** VLAST project promises to make significant contributions to the field of gamma-ray astronomy and enhance our understanding of the cosmos.

关键词： Space astronomy Gamma-ray telescope Calorimeter Monte Carlo simulation

Unidirectional movement behavior of underwater bubbles on the wettability gradient mesh via asymmetrical bounce

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Science China Chemistry 2024年第8期67卷 2606-2613页

作者： Yuzhen ning Zhihong Zhao Shuang Ben Qiang Li Cunming Yu Xudong Zhang Huawei Chen Kesong Liu Lei jiang School of Mechanical Engineering and Automation Beihang UniversityBeijing 100191China Key Laboratory of Bio-Inspired Smart Interfacial Science and Technology School of ChemistryBeihang UniversityBeijing 100191China Research Institute of Aero-Engine Beihang UniversityBeijing 100191China School of Materials Science and Engineering Shenyang Ligong UniversityShenyang 110159China Tianmushan Laboratory Hangzhou 310023China The Analysis Testing CenterBeihang UniversityBeijing 100191China

The impact of underwater bubbles on solid surfaces with a gradient wettability is important for fundamental science and technological applications. Despite progress in the translational motion of underwater bubbles on asymmetric surface, a fundamental dynamic understanding of asymmetrical bounce behavior of the underwater bubble needs to be further ***, we investigate asymmetrical bounce of underwater bubbles after impacting the wettability gradient copper mesh *** bounce of the underwater bubble on the wettability gradient mesh(WGM) surface is composed by asymmetrical spread in the spread process and asymmetrical recoil in the recoil process, which induce the unidirectional movement ***, effective bubble-size manipulation can be easily implemented due to different volumes of bubbles remaining at different locations of WGM surface. We envision that this work will provide a new understanding of asymmetrical bounce behavior of the underwater bubble on the wettability gradient surface, and propose a novel and feasible strategy for constructing the underwater bubble manipulation system.

关键词： asymmetrical bounce unidirectional movement behavior gradient wettability

{1012}twin–twin intersection-induced lattice rotation and dynamic recrystallization in Mg–6Al–3Sn–2Zn alloy

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Journal of Magnesium and Alloys 2024年第4期12卷 1529-1539页

作者： Bin-jiang Lv Sen Wang Fu-Hao Gao ning Cui Yi-Nan Li Tie-Wei Xu Feng Guo School of Mechanical and Automotive Engineering Qingdao University of Technology266520China Key Lab of industrial Fluid Energy Conservation and Pollution Control Qingdao University of Technology266520China

This study investigated the formation mechanism of new grains due to twin–twin intersections in a coarse-grained Mg–6Al–3Sn–2Zn alloy during different strain rates of an isothermal *** results of electron backscattered diffraction investigations showed that the activated twins were primarily{1012}tension twins,and 60°boundaries formed due to twin–twin intersections under different strain *** twin variants with 60°boundaries transformed into new grains through lattice rotations at a low strain rate(0.01 s^(−1)).At a high strain rate(10 s^(−1)),the regions surrounded by subgrain boundaries through high-density dislocation arrangement and the 60°boundaries transformed into new grains via dynamic recrystallization.

关键词： Mg alloy Twin-twin intersection Lattice rotation Dynamic recrystallization