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Microstructure and properties of mechanical alloying particles reinforced aluminum matrix composites prepared by semisolid stirring pouring method

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China Foundry 2016年第3期13卷 176-181页

作者： Yao-qiang Si Zhi-yong You Jing-xin Zhu lai-qiang cai Jin-shan Zhang College of Materials Science and Engineering Taiyuan University of Technology

Aluminum matrix composites reinforced with mechanical alloying particles(SiC_p) were fabricated by the semisolid stirring pouring method. The inf luence of mechanical alloying particles and Mg on the microstructure and mechanical properties of the composites was investigated by means of optical microscopy(OM), X-ray diffraction scanning(XRD), electron microscopy(SEM) and energy dispersive spectroscopy(EDS). Results show that the addition of Mg converts the agglomerate mechanical al oying particles in ZL101 matrix composites into dispersed distribution in ZL101-Mg matrix composites, large matrix grains into f ine equiaxed matrix grains, and eutectic phase into f ine particles. So the mechanical properties of ZL101-Mg matrix composites are better than those of ZL101 matrix composites. The mechanical properties of ZL101/ZL101-Mg matrix composites are gradually increased with the increase of the volume fraction of mechanical alloying particles. When the volume fraction of mechanical alloying particles is 3%, the Vickers hardness and ultimate tensile strength of the ZL101/ZL101-Mg matrix composites reach their maximum values.

关键词： mechanical alloying particle aluminum matrix composites grain refinement mechanical properties

Remote sensing image encryption algorithm utilizing 2D Logistic memristive hyperchaotic map and SHA-512

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Science China(Technological Sciences) 2024年第5期67卷 1553-1566页

作者： lai qiang LIU Yuan YANG Liang School of Electrical and Automation Engineering East China Jiaotong UniversityNanchang330013China

The two-dimensional Logistic memristive hyperchaotic map(2D-LMHM)and the secure hash SHA-512 are the foundations of the unique remote sensing image encryption algorithm(RS-IEA)suggested in this *** proposed map is formed from the improved Logistic map and the memristor,which has wide phase space and hyperchaotic range and is exceptionally excellent to be utilized in specific *** proposed image algorithm uses the permutation-assignment-diffusion *** generates two position matrices in a progressive manner to achieve an efficient random exchange of pixel positions,assignment is carried through on the image pixels of the permutated image to entirely remove the original image information,strengthening the relationship between permutation and diffusion,and loop diffusion in two different directions can use subtle changes of pixels to affect the whole *** random key and plain-image SHA-512 hash values are used to produce an additional key,which is then utilized to figure out the permutation parameters and the initial value of a chaotic *** experimental results with the average NPCR=99.6094%(NPCR:number of pixels change rate),average UACI=33.4638%(UACI:unified average changing intensity),100%pass rate of the targets in the test set,the average correlation coefficient is 0.00075,and the local information entropy is 7.9025,which shows that the algorithm is able to defend against a variety of illegal attacks and provide more trustworthy protection than some of the existing state-of-the-art algorithms.

关键词： chaos memristive hyperchaotic map remote sensing SHA-512 image encryption RS-IEA

Mechanical property of cylindrical sandwich shell with gradient core of entangled wire mesh

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Defence Technology（防务技术） 2024年第1期31卷 510-522页

作者： Xin Xue Chao Zheng Fu-qiang lai Xue-qian Wu Institute of Metal-rubber&Vibration Noise School of Mechanical Engineering and AutomationFuzhou UniversityFuzhou350116China Fujian Metallurgical Industry Design Institute Fuzhou350116China

To explore the wide-frequency damping and vibration-attenuation performances in the application of aerospace components,the cylindrical sandwich shell structure with a gradient core of entangled wire mesh was proposed in this ***,the gradient cores of entangled wire mesh in the axial and radial directions were prepared by using an in-house Numerical Control weaving machine,and the metallurgical connection between skin sheets and the gradient core was performed using vacuum ***,to investigate the mechanical properties of cylindrical sandwich shells with axial or radial gradient cores,quasi-static and dynamic mechanical experiments were carried *** primary evaluations of mechanical properties include secant stiffness,natural frequency,Specific Energy Absorption(SEA),vibration acceleration level,and so *** results suggest that the vibration-attenuation performance of the sandwich shell is remarkable when the high-density core layer is at the end of the shell or abuts the inner *** axial gradient material has almost no influence on the vibration frequencies of the shell,whereas the vibration frequencies increase dramatically when the high-density core layer approaches the ***,compared to the conventional sandwich shells,the proposed functional grading cylindrical sandwich shell exhibits more potential in mass reduction,stiffness designing,and energy dissipation.

关键词： Entangled wire mesh Gradient cylindrical sandwich shell Vacuum brazing Secant stiffness Damping

Experimental and numerical study of hypervelocity impact damage on composite overwrapped pressure vessels

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Defence Technology（防务技术） 2024年第1期31卷 58-72页

作者： Yong-Pan Duan Run-qiang Chi Bao-Jun Pang Yuan cai Hypervelocity Impact Research Center Harbin Institute of TechnologyHarbin150080China College of Science Heilongjiang University of Science and TechnologyHarbin 150022China

Ground-based tests are important for studying hypervelocity impact(HVI)damage to spacecraft pressure vessels in the orbital debris *** analyzed the damage to composite overwrapped pressure vessels(COPVs)in the HVI tests and classified the damage into non-catastrophic damage and catastrophic *** proposed a numerical simulation method to further study non-catastrophic damage and revealed the characteristics and mechanisms of non-catastrophic damage affected by impact conditions and internal *** fragments of the catastrophically damaged COPVs were collected after the *** crack distribution and propagation process of the catastrophic ruptures of the COPVs were *** findings contribute to understanding the damage characteristics and mechanisms of COPVs by HVIs.

关键词： Orbital debris Hypervelocity impact Composite overwrapped pressure vessels Damage mechanisms

Pre-activated macrophage membrane-encased aggregationinduced emission featuring nanoparticles:a novel possibility for tuberculosis treatment

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Signal Transduction and Targeted Therapy 2024年第7期9卷 2848-2850页

作者： qiang cai Yihao Tian Quazi T.H.Shubhra Department of Neurosurgery Renmin Hospital of Wuhan UniversityWuhanChina Department of Human Anatomy and Histology and Embryology School of Basic Medical SciencesWuhan UniversityWuhanChina Institute of Chemistry University of Silesia in KatowiceSzkolna 9KatowicePoland

In a recent study published in Nature Nanotechnology,Li et *** the synthesis of a novel photosensitizer with unique aggregation-induced emission(AIE)characteristics.1 They microencapsulated this photosensitizer inside engineered nanoparticles(NPs)coated with pre-activated macrophage cell membranes(CMs),an innovative approach marking a significant leap in nanomedicine by offering a pathway to potent tuberculosis(TB)treatments that bypass antibiotic resistance with unparalleled precision.

关键词： tuberculosis macrophage aggregation

New insights into the pre-lithiation kinetics of single-crystalline Ni-rich cathodes for long-life Li-ion batteries

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Green Energy & Environment 2024年第3期9卷 556-564页

作者： qiang Han Lele cai Zhaofeng Yang Yanjie Hu Hao Jiang Chunzhong Li Shanghai Engineering Research Center of Hierarchical Nanomaterials School of Chemical EngineeringEast China University of Science and TechnologyShanghai200237China Key Laboratory for Ultrafine Materials of Ministry of Education School of Materials Science and EngineeringEast China University of Science and TechnologyShanghai200237China

Developing single-crystalline Ni-rich cathodes is an effective strategy to improve the safety and cycle life of Li-ion batteries(LIBs).However,the easy-to-loss of Li and O in high-temperature lithiation results in unsatisfactory ordered layered structure and ***,we demonstrate the synthesis of highly-ordered and fully-stoichiometric single-crystalline LiNi_(0.83)Co_(0.12)Mn_(0.05)O_(2)(SC-NCM83)cathodes by the regulation of pre-lithiation *** well-balanced pre-lithiation kinetics have been proved to greatly improve the proportion of layered phase in the intermediate by inhibiting the formation of metastable spinel phase,which promoted the rapid transformation of the intermediate into highly-ordered layered SC-NCM83 in the subsequent lithiation *** coating a layer of Li_(2)O–B_(2)O_(3),the resultant cathodes deliver superior cycling stability with 90.9%capacity retention at 1C after 300 cycles in pouch-type full *** enhancement mechanism has also been *** findings exhibit fundamental insights into the pre-lithiation kinetics process for guiding the synthesis of high-quality singlecrystalline Ni-rich cathodes.

关键词： Single-crystalline cathode Ni-rich oxides Pre-lithiation Li-ion batteries Surface modification

Dynamics of Land Use/Land Cover Considering Ecosystem Services for a Dense-Population Watershed Based on a Hybrid Dual-Subject Agent and Cellular Automaton Modeling Approach

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Engineering 2024年第6期37卷 182-195页

作者： Yutong Li Yanpeng cai qiang Fu Xiaodong Zhang Hang Wan Zhifeng Yang Guangdong Provincial Key Laboratory of Water Quality Improvement and Ecological Restoration for Watersheds Institute of Environmental and Ecological EngineeringGuangdong University of TechnologyGuangzhou 510006China School of Water Conservancy and Civil Engineering Northeast Agricultural UniversityHarbin 150030China School of Environmental Science and Engineering Shandong UniversityQingdao 266000China

Land use/land cover represents the interactive and comprehensive influences between human activities and natural conditions,leading to potential conflicts among natural and human-related issues as well as among *** study introduced economic standards for farmers.A hybrid approach(CA-ABM)of cellular automaton(CA)and an agent-based model(ABM)was developed to effectively deal with social and land-use synergic issues to examine human–environment interactions and projections of land-use conversions for a humid basin in south *** attributes and socioeconomic data were used to analyze land use/land cover and its drivers of *** major modules of the CA-ABM are initialization,migration,assets,land suitability,and land-use change *** estimates of the factors influencing the urban land-use conversion probability were captured using parameters based on a spatial logistic regression(SLR)***,multicriteria evaluation(MCE)and Markov models were introduced to obtain empirical estimates of the factors affecting the probability of ecological land *** agent-based CA-SLR-MCE-Markov(ABCSMM)land-use conversion model was proposed to explore the impacts of policies on land-use *** model can reproduce observed land-use patterns and provide links for forest transition and urban expansion to land-use decisions and ecosystem *** results demonstrated land-use simulations under multi-policy scenarios,revealing the usefulness of the model for normative research on land-use management.

关键词： Land use/land cover Human-environment interactions Agent-based model Cellular automaton

Climate warming is significantly influenced by rising summer maximum temperatures: insights from tree-ring evidence of the Western Tianshan Mountains, China

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Journal of Forestry Research 2024年第5期35卷 47-59页

作者： Meng Ren Yu Liu Qiufang cai qiang Li Huiming Song Changfeng Sun The State Key Laboratory of Loess and Quaternary Geology Institute of Earth EnvironmentChinese Academy of SciencesXi’an 710061People’s Republic of China Xi’an Institute for Innovative Earth Environment Research Xi’an 710061People’s Republic of China Institute of Desert Meteorology China Meteorological AdministrationÜrümqi 830002People’s Republic of China Center for Excellence in Quaternary Science and Global Change Chinese Academy of SciencesXi’an 710061People’s Republic of China School of Human Settlements and Civil Engineering Xi’an Jiaotong UniversityXi’an 710049People’s Republic of China Qingdao National Laboratory for Marine Science and Technology Qingdao 266237People’s Republic of China

As one of the regions most affected by global cli-mate warming,the Tianshan mountains has experienced sev-eral ecological crises,including retreating glaciers and water *** warming in these mountains is considered mainly to be caused by increases in minimum temperatures and winter temperatures,while the influence of maximum temperatures is *** this study,a 300-year tree-ring chronology developed from the Western Tianshan Moun-tains was used to reconstruct the summer(June-August)maximum temperature(T_(max6-8))variations from 1718 to *** reconstruction explained 53.1% of the variance in the observed T_(max6-8).Over the past 300 years,the T_(max6-8)reconstruction showed clear interannual and decadal *** was a significant warming trend(0.18°C/decade)after the 1950s,which was close to the increasing rates of the minimum and mean *** increase in maximum temperature was also present over the whole Tianshan mountains and its impact on climate warming has *** T_(max6-8) variations in the Western Tianshan mountains were influenced by frequent volcanic eruptions combined with the influence of solar activity and the sum-mer North Atlantic *** study reveals that cli-mate warming is significantly influenced by the increase in maximum temperatures and clarifies possible driving mech-anisms of temperature variations in the Western Tianshan mountains which should aid climate predictions.

关键词： Tree rings Western Tianshan mountains Temperature change Climate warming

Dcalycinumines A-E,Alkaloids with Cytotoxic Activities of Nasopharyngeal Carcinoma Cells from Daphniphyllum calycinum

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Chinese Journal of Chemistry 2024年第1期42卷 35-42页

作者： Qing Tang Xiao-Yong Dai qiang Lin Zhi-Peng Ling Yi-Kun Hao Tian-Xi Zhu Ji-Hui Zhang Yi-Bo Hou Yao-Lan Li lai-qiang Huang Jing-Hao Wang Guo-cai Wang Yu-Bo Zhang Guangdong Clinical Translational Centerfor Targeted Drug Department of PharmacologySchoolof MedicineJinan University GuangzhouGuangdong 510632China Institute of Traditional Chinese Medicine&Natural Products Guangdong Province Key Laboratory of Pharmacodynamic Constituents of TCM and New Drugs ResearchCollegeof PharmacyJinan UniversityGuangzhouGuangdong511443China Institute of Biopharmaceutical and Health Engineering Shenzhen Key Laboratory of Gene and Antibody TherapyState Key Laboratory of Chemical OncogenomicsShenzhen International Graduate SchoolTsinghua UniversityShenzhenGuangdong 518055China The Guangzhou Key Laboratoryof Basic and Translational Research on Chronic Disease Department of PharmacyThe First Affiliated HospitalJinan UniversityGuangzhouGuangdong 510630China

Fivenovel Daphniphyllum alkaloids,named dcalycinumines A-E(1-4,6),andeight previously described Daphniphyllum alkaloids(5,7-13)were isolated from Daphniphyllum *** 1 is the first Daphniphyllum alkaloid possessing a highly rearranged 6/6/6/7/5/6 hexacyclic architecture with a unique 3-methyl-1-azabicyclo[4,4,0]decane ring *** 2 represents a rare diamino Daphniphyllum alkaloid with an unprecedented 6/5/5/6/6/5 carbon skeleton featuring a unique 1-aza-6-azaspiro[4,5]decane unit,whereas 3 also represents a rare diamino Daphniphyllum alkaloid as a possible precursor of *** 4 is the second example of c-22-nor yuzurimine-type *** structures and absolute configurations were elucidated by HRESIMS,NMR spectroscopic analyses,EcD calculations,and single-crystal X-ray ***,compound 1 showed remarkable antitumor activities,which could inhibit the proliferation,migration and invasion of nasopharyngeal carcinoma cells,and promoted nasopharyngeal carcinoma cells apoptosis.

关键词： Daphniphyllum calycinum Natural products Daphniphyllum alkaloid Structural elucidation Biological activity Apoptosis Nasopharyngealcarcinoma