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Mitigating the negative catalytic effect of CuO by FAS-17 coated Al nanopowder:Isothermal ageing of Al/CuO nanothermite at 71°C and 60%relative humidity

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Defence Technology（防务技术） 2024年第4期34卷 156-167页

作者： Fuwei Li Qian Wang Jian cheng Zehua zhang Yuxuan Zhou Keer Ouyang Jianbing xu Yinghua Ye Ruiqi Shen School of Chemistry and Chemical Engineering Nanjing University of Science&TechnologyNanjing 210094China Micro-Nano Energetic Devices Key Laboratory Ministry of Industry and Information TechnologyNanjing 210094JiangsuChina Institute of Space Propulsion Nanjing University of Science and TechnologyNanjing 210094China

The safety and reliability of weapon systems would be significantly affected by changes in the performance of energetic materials due to ambient temperature and *** have promising applications due to their excellent *** it becomes extremely important to understand their aging and failure process in the environment before using ***,the aging and failure process of Al/CuO in 71°C/60%RH were investigated,and showed that CuO nanoparticles negatively catalyze Al nanopowders,resulting in rapid *** anti-aging effect of FAS-17-coated Al nanopowder was also *** aging process of Al,Al/CuO,and Al@FAS-17/CuO in high humidity and heat environment were revealed by quasi-in situ SEM and TEM *** with the aging of pure Al,the Al nanopowder in the nanothermites strongly agglomerated with the CuO nanopowder and hydrated *** may be caused by CuO catalyzed hydration of Al *** energy release experiments showed that the performance of Al/CuO decreased rapidly and failed to ignite after 4 h of *** contrast,the Al@FAS-17/CuO thermite can achieve long-term stability of up to 60 h in the same environment by simple cladding of *** is found that FAS-17 coated Al nanopowder can prevent both particle agglomeration and water erosion,which is an effective means to make nanothermites application in high humidity and heat environment.

关键词： Al/CuO nanothermite FAS-17 coating Aging and failure process

Deflagration and detonation induced by shock wave focusing at different Mach numbers

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Chinese Journal of Aeronautics 2024年第2期37卷 249-258页

作者： Zezhong YANG Jun cheng Bo zhang School of Aeronautics and Astronautics Shanghai Jiao Tong UniversityShanghai 200240China

Shock wave focusing is an effective way to create a hot spot or a high-pressure and hightemperature region at a certain place,showing its unique usage in detonation initiation,which is beneficial for the development of detonation-based *** flame propagation behavior after the autoignition induced by shock wave focusing is crucial to the formation and self-sustaining of the detonation *** this study,wedge reflectors with two different angles(60°and 90°)and a planar reflector are employed,and the Mach number of incident shock waves ranging from 2.0 to 2.8 is utilized to trigger different flame propagation *** pressure transducers and the high-speed schlieren imaging system are both employed to investigate the shock-shock collision and ignition *** results reveal a total of four flame propagation modes:deflagration,DDT(Deflagration-to-Detonation Transition),unsteady detonation,and direct *** detonation wave formed in the DDT and unsteady detonation mode is only approximately 75%-85%of the Chapman-Jouguet(C-J)speed;meanwhile,the directly induced detonation wave speed is close to the C-J *** waves,which are strong evidence for the existence of detonation waves,are discovered in *** usage of wedge reflectors significantly reduces the initial pressure difference ratio needed for direct detonation *** also provide a practical method for differentiating between detonation and deflagration modes,which involves contrasting the speed of the reflected shock wave with the speed of the theoretically nonreactive reflected shock *** findings should serve as a reference for the detonation initiation technique in advanced detonation propulsion engines.

关键词： Deflagration Detonation Hydrogen Ignition Shock wave focusing

Nutrient transport following water transfer through the world's largest water diversion channel

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Journal of Environmental Sciences 2024年第1期135卷 703-714页

作者： Yuanhui cheng Hong zhang Wei Yin State Key Laboratory of Environmental Aquatic Chemistry Research Center for Eco-Environmental SciencesChinese Academy of SciencesBeijing 100085 China Changjiang Water Resources Protection Institute Wuhan 430051China University of Chinese Academy of Sciences Beijing 100049China

Nutrient levels in the artificial channel constructed for the Middle Route Project are significant indicators of water quality safety and aquatic ecological integrity for this large,interbasin ***,the distribution and transport of nutrients along the channel were poorly *** on a time-series dataset as well as mass balance and material flow analysis methods,the water and nutrient transport fluxes in the Middle Route of the South-to-North Water Diversion Project were identified in this *** results indicate that the nutrient concentrations varied considerably with time,but there was no significant difference among the 30 stations of the main *** temperature difference was the major factor in the large fluctuations of water quality indicators over *** nutrient loadings varied with the water volume outputs from the main channel to the waterreceiving *** deposition was an important source of nutrients in the main channel,accounting for 9.13%,20.6%,and 0.635%of the nitrogen,phosphorus,and sulfur input from the Danjiangkou Reservoir,*** 2021,a net accumulation of 988 tons of N,29 tons of P,and 2,540 tons of S,respectively,were present in the main *** increase of these external and internal nutrient loadings would cause water quality fluctuation and deterioration in some local sections of the main *** study quantified the spatial and temporal patterns of nutrient transport in the Middle Route and revealed the ecological effects on the aquatic environment,assisting authorities on the project to develop effective water conservation strategies.

关键词： Nutrient transport Spatiotemporal patterns The Middle Route The South-to-North Diversion Project Hydro-ecological effects Water-receiving cities

Streamflow abrupt change and the driving factors in glacierized basins of Tarim Basin,Northwest China

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Advances in Climate Change Research 2024年第1期15卷 75-89页

作者： cheng-De YANG Min xu Shi-Chang KANG Cong-Sheng FU Wei zhang Di-Di HU State Key Laboratory of Cryospheric Science Northwest Institute of Eco-Environment and ResourcesChinese Academy of SciencesLanzhou 730000China University of Chinese Academy of Sciences Beijing 100049China Key Laboratory of Watershed Geographic Sciences Nanjing Institute of Geography and LimnologyChinese Academy of SciencesNanjing 210000China

A climate transition towards warm-wet conditions in Northwest China has drawn much *** continuous climate change and universal glacier degradation,increasing water-related hazards and vulnerability have become one of the important problems facing the Tarim ***,the impacts of the climate transition on streamflow abrupt change and extreme hydrological events were less discussed,especially in glacial *** the present study,the discharge datasets in four glacial basins of Tarim Basin from 1979 to 2018 were constructed using the GRU-GSWAT+model *** differences in streamflow characteristics,the shift of hydrological extreme pattern,and potential changes of the controlling factors before and after the abrupt changes were *** results indicated that the abrupt change point(ACP)in streamflow occurred in 2000 in the Qarqan River Basin,2002 in the Weigan River Basin,and 1994 in the Aksu River Basin and the Yarkant River Basin.A general decrease in streamflow before the ACP has shifted to a notable upward trend in the Qarqan River Basin and the Aksu River Basin,while minor upward fluctuations were observed in other ***,the hydrological characteristics in extreme events vary dramatically before and after the ACPs,characterized by a pronouncing shift from drought-dominant pattern to wet events dominated *** driven climate factors have been altered after the ACPs with notable spatial heterogeneity,in which temperature remained as the dominant role in meltwater-dominated basins while the influence of precipitation has increased after the ACPs,whereas the sensitivity of temperature on streamflow change has been enhanced in basins dominated by precipitation such as the Qarqan River *** to the evident warming-wetting trend and glacier compensation effect,both the inter-annual and intra-annual streamflow fluctuations can be efficiently smoothed in basins with a high glacier area ratio(GAR).These findings provide a

关键词： Abrupt change Streamflow Hybrid model Tarim Basin Glacier

Incorporating metal nanoparticles in porous materials via selective heating effect using microwave

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Nano Research 2024年第4期17卷 3175-3179页

作者： Yingyu Zhou Jiacheng Liu Fuyuan Sun Junchen Ouyang Ruifa Su Fanchen Meng Yongqi Luo cheng xu Weina zhang Suoying zhang Fengwei Huo Key Laboratory of Flexible Electronics(KLOFE)&Institute of Advanced Materials(IAM) Nanjing Tech UniversityNanjing 211816China

Metal nanoparticle@porous material composites have attracted increasing attention due to their excellent synergistic catalytic ***,it is a challenge to introduce metal nanoparticles into cavities of porous materials without agglomeration on the *** the progress achieved,a universal approach that can integrate different kinds of metal nanoparticles and porous materials is still highly *** we report a facile and general approach to fabricating metal nanoparticle@porous materials by microwave-triggered selective *** microwave can pass through the non-polar solvent and act on the polar solvent in the porous materials,causing the polar solvent to be heated,vaporized,and away from the pores of porous *** local void produced by the escape of polar solvent facilitates non-polar solvent containing metallic precursor to be dragged into the narrow pores,followed by further reduction,resulting in the complete encapsulation of nanoparticles.A series of metal nanoparticles@porous materials,ranging from metal-organic frameworks(MOFs)to zeolites,are successfully prepared by this method and show excellent size selectivity in catalytic reactions.

关键词： porous material nanoparticle encapsulation microwave synthesis selective heating effect selective catalysis

A telomere-to-telomere genome assembly of Hongyingzi,a sorghum cultivar used for Chinese Baijiu production

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The Crop Journal 2024年第2期12卷 635-640页

作者： Yanqing Ding Yilin Wang Jianxia xu Feng Jiang Wenzhen Li Qiaoling zhang Longping Yang Zhenyu Zhao Bin cheng Ning Cao xu Gao Xin zhang Guihua Zou Fan Yang Liyi zhang Guizhou Institute of Upland Crops Guizhou Academy of Agricultural SciencesGuiyang 550006GuizhouChina Kweichow Moutai Co. Ltd.Maotai TownRenhuai 564501GuizhouChina Kweichow Moutai Distillery(Group)Hongyingzi Agricultural Technology Development Co. Ltd.Maotai TownRenhuai 564501GuizhouChina Wuhan GrandOmics Biosciences Co. Ltd.Grandomics BiosciencesWuhan 430000HubeiChina Institute of Crop and Nuclear Technology Utilization Zhejiang Academy of Agricultural SciencesZhejiang

Sorghum(Sorghum bicolor(L.)Moench)is a world cereal crop used in China for producing Baijiu,a distilled *** report a telomere-to-telomere genome assembly of the Baijiu cultivar Hongyingzi,HYZ-T2T,using ultralong *** 10 chromosome pairs contained 33,462 genes,of which 93%were functionally *** 20 telomeres and 10 centromeric regions on the HYZ-T2T chromosomes were predicted and two consecutive large inversions on chromosome 2 were characterized.A 65-gene reconstruction of the metabolic pathway of tannins,the flavor substances in Baijiu,was performed and may advance the breeding of sorghum cultivars for Baijiu production.

关键词： Sorghum Telomere-to-telomere assembly Hongyingzi(HYZ) Chinese Baijiu-making cultivar

Effective assignment of positional isomers in dimeric shikonin and its analogs by ^(1)H NMR spectroscopy

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Chinese Chemical Letters 2024年第5期35卷 223-226页

作者： Ling-Hao Zhao Hai-Wei Yan Jian-Shuang Jiang xu zhang Xiang Yuan Ya-Nan Yang Pei-cheng zhang State Key Laboratory of Bioactive Substance and Function of Natural Medicines Institute of Materia MedicaChinese Academy of Medical Sciences and Peking Union Medical CollegeBeijing 100050China

An approach for distinguishing two types of positional isomers of dimeric shikonin and its analogs was explored with ^(4)JC,H long-range correlation by prolonging the acquisition time at ^(2,3)JC,H values of 2.0 and ***,the ^(1)H(proton)nuclear magnetic resonance(NMR)pattern of phenolic hydroxyl protons was developed as a“diagnosis signal”to ascertain the relative location of each side chain in DMSO-d_(6) at sample concentrations of 0.022-0.034 mol/*** chemical shift differences of 0.6ppm between OH-5' and OH-1 and between OH-8'and OH-4 are assigned to Type A and Type B,*** reported ambiguous structures were corrected by this ***,the steric structures of isolated compounds were elucidated by quantum chemical calculations of electronic circular dichroism(ECD)spectra.

关键词： Arnebia euchroma Dimeric hydroxyl naphthoquinones Positional isomers ^(1)H NMR spectroscopy Chemical shift difference

A composite material model for investigation of micro-fracture mechanism of brittle rock subjected to uniaxial compression

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Journal of Central South University of Technology 2001年第4期8卷 258-262页

作者： CHEN Feng,SUN Zong qi,xu Ji cheng,zhang Jing yi (Key Laboratory of Nonferrous Metal Materials Science & Engineering, Central South University, Changsha 410083, China) Key Laboratory of Nonferrous Metal Materials Science & Engineering Central South University Changsha China

A two phase model of rock was proposed in order to investigate the mechanism of brittle fracture due to uniaxial compression, in which rock was considered to be a composite material consisting of hard grains and colloids. The stress state in colloid region near grains was calculated using Finite Element Method (FEM). The influence of the tensile stresses on the crack initiation and failure process of brittle rock subjected to uniaxial compression was investigated by numerical experiments. The FE results show that tensile stresses are induced easily in the neighboring area of hard grains with the maximum value near grain boundaries. The distribution of tensile stresses depends on the relative position of hard grains. The cracks initiated just near the boundary area of hard grains, which was governed by tensile stress. These results clearly reveal the micro fracture mechanism of brittle rock loaded by uniaxial compression. It can be concluded that the failure mode of brittle rock under uniaxial compression is still tensile fracture from the point view of microstructure. However, since the wide colloid region is still under compressive stress state, further propagation of boundary cracks through this region obviously needs more external load, thus causing the uniaxial compressive strength of rock much higher than its tensile strength obtained via Brazilian (splitting)

关键词： two-phase model micro-fracture rock uniaxial compression

Achieving a superior Na storage performance of Fe-based Prussian blue cathode by coating perylene tetracarboxylic dianhydride amine

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Carbon Energy 2024年第5期6卷 53-64页

作者： Xin-Yuan Fu Lu-Lu zhang Zhao-Yao Chen Yunkai xu Junxiu Wu cheng-cheng Wang Xiao-Kai Ding xue-Lin Yang Jun Lu Hubei Provincial Collaborative Innovation Center for New Energy Microgrid College of Electrical Engineering&New EnergyChina Three Gorges UniversityYichangHubeiChina College of Materials and Chemical Engineering China Three Gorges UniversityYichangHubeiChina College of Chemical and Biological Engineering Zhejiang UniversityHangzhouChina

Fe-based Prussian blue(Fe-PB)cathode material shows great application potential in sodium(Na)-ion batteries due to its high theoretical capacity,long cycle life,low cost,and simple preparation ***,the crystalline water and vacancies of Fe-PB lattice,the low electrical conductivity,and the dissolution of metal ions lead to limited capacity and poor cycling *** this work,a perylene tetracarboxylic dianhydride amine(PTCDA)coating layer is successfully fabricated on the surface of Fe-PB by a liquid-phase *** aminated PTCDA(PTCA)coating not only increases the specific surface area and electronic conductivity but also effectively reduces the crystalline water and vacancies,which avoids the erosion of Fe-PB by ***,the PTCA layer reduces the charge transfer resistance,enhances the Na-ion diffusion coefficient,and improves the structure *** PTCA-coated Fe-PB exhibits superior Na storage performance with a first discharge capacity of 145.2 mAh g^(−1) at 100 mA g^(−1).Long cycling tests exhibit minimal capacity decay of 0.027%per cycle over 1000 cycles at 1 A g^(−1).Therefore,this PTCA coating strategy has shown promising competence in enhancing the electrochemical performance of Fe-PB,which can potentially serve as a universal electrode coating strategy for Na-ion batteries.

关键词： cathode material coating Fe-based Prussian blue Na-ion batteries perylene tetracarboxylic dianhydride amine