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Defence Technology（防务技术） 2024年第5期35卷 18-46页

作者： Man Xu Nanxi Xiang Ping Yin Qi lai siping Pang school of Materials science&Engineering Beijing Institute of TechnologyBeijing 100081China Beijing Institute of Technology Chongqing Innovation Center Chongqing 401120China

From the standpoint of chemical structures,the organic backbones of energetic materials can be classified into aromatic rings,nonaromatic rings,and open *** the category of aromatic energetic compounds exhibits several advantages in the regulation of energetic properties,the nonaromatic heterocycles,assembling nitramino explosophores with simple alkyl bridges,still have prevailed in benchmark *** methylene bridge plays a pivotal role in the constructions of the classic nonaromatic heterocycle-based energetic compounds,e.g.,hexahydro-1,3,5-trinitro-1,3,5-triazine(RDX)and octahydro-1,3,5,7-tetranitro-1,3,5,7-tetrazocine(HMX),whereas ethylene bridge is the core moiety of state-of-the-art explosive 2,4,6,8,10,12-hexanitro-2,4,6,8,10,12-hexaazaisowurtzitane(CL-20).In this context,it is of great interest to employ simple and practical bridges to assemble aromatic and nonaromatic nitrogen-rich heterocycles,thereby expanding the structural diversity of energetic materials,e.g.,bridged and fused nitrogen-rich ***,alkyl-bridged poly-heterocycles highlight the potential for the open chain type of energetic *** this review,the development of alkyl bridges in linking nitrogen-rich heterocycles is presented,and the perspective of the newly constructed energetic backbones is summarized for the future design of advanced energetic materials.

关键词： Energetic materials Alkyl bridge strategy Nitrogen-rich azoles Fused heterocycles Azoles

Dynamics and vibration reduction performance of asymmetric tristable nonlinear energy sink

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Applied Mathematics and Mechanics(English Edition) 2024年第3期45卷 389-406页

作者： Hongyan CHEN Youcheng ZENG Hu DING siukai lai Liqun CHEN school of Mechanical Engineering University of Science and Technology BeijingBeijing 100083China shanghai key Laboratory of Mechanics in Energy Engineering Shanghai Frontier Science Center of MechanoinformaticsShanghai Institute of Applied Mathematics and MechanicsSchool of Mechanics and Engineering ScienceShanghai UniversityShanghai 200444China Department of Civil and Environmental Engineering The Hong Kong Polytechnic UniversityKowloonHong KongChina

With its complex nonlinear dynamic behavior,the tristable system has shown excellent performance in areas such as energy harvesting and vibration suppression,and has attracted a lot of *** this paper,an asymmetric tristable design is proposed to improve the vibration suppression efficiency of nonlinear energy sinks(NEss)for the first *** proposed asymmetric tristable NEs(ATNEs)is composed of a pair of oblique springs and a vertical ***,the three stable states,symmetric and asymmetric,can be achieved by the adjustment of the distance and stiffness asymmetry of the oblique *** governing equations of a linear oscillator(LO)coupled with the ATNEs are *** approximate analytical solution to the coupled system is obtained by the harmonic balance method(HBM)and verified *** vibration suppression efficiency of three types of ATNEs is *** results show that the asymmetric design can improve the efficiency of vibration reduction through comparing the chaotic motion of the NEs oscillator between asymmetric steady *** addition,compared with the symmetrical tristable NEs(TNEs),the ATNEs can effectively control smaller structural *** other words,the ATNEs can effectively solve the threshold problem of TNEs failure to weak ***,this paper reveals the vibration reduction mechanism of the ATNEs,and provides a pathway to expand the effective excitation amplitude range of the NEs.

关键词： asymmetric nonlinear energy sink(NEs) tristable vibration control po-tential barrier

A booming field of large animal model research

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Zoological Research 2024年第2期45卷 311-313页

作者： Xiao-Jiang Li Liangxue lai Guangdong key Laboratory of Non-human Primate Research Key Laboratory of CNS Regeneration(Ministry of Education)GHM Institute of CNS RegenerationJinan UniversityGuangzhouGuangdong 510632China state key Laboratory of Bioactive Molecules and Druggability Assessment Jinan UniversityGuangzhouGuangdong 510632China CAs key Laboratory of Regenerative Biology Guangdong Provincial Key Laboratory of Stem Cell and Regenerative MedicineGuangzhou Institutes of Biomedicine and HealthChinese Academy of SciencesGuangzhouGuangdong 510530China

Animal models are integral to the study of fundamental biological processes and the etiology of human *** animal models,especially those involving mice,have yielded abundant and significant insights,greatly enhancing ... 详细信息

关键词： mechanisms insight field

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

Lacticaseibacillus rhamnosus Probio-M9 may be vertically transmitted from mother to infant during lactation based on faeces metagenomics

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Food science and Human Wellness 2024年第2期13卷 721-728页

作者： Lan Yang lai-Yu kwok Zhihong sun Heping Zhang key Laboratory of Dairy Biotechnology and Engineering Ministry of EducationInner Mongolia Agricultural UniversityHohhot 010018China key Laboratory of Dairy Products Processing Ministry of Agriculture and Rural AffairsInner Mongolia Agricultural UniversityHohhot 010018China Inner Mongolia key Laboratory of Dairy Biotechnology and Engineering Inner Mongolia Agricultural UniversityHohhot 010018China

Probiotics exert beneficial effects on the *** study aimed to investigate whether maternally ingested Lacticaseibacillus rhamnosus Probio-M9 during pregnancy could access and colonize the infant *** study recruited one pregnant woman,who ingested Probio-M9 daily from 35 weeks of gestation to *** of the mother-infant pair were regularly collected from one month before delivery to 6 months of infant's age for metagenomic ***-M9 genomes were mappable to all infant fecal samples,suggesting the ingested probiotics could be vertically transmitted from mother to ***-or mother-specific differential metabolic pathways were found between the maternal and infant's gut microbiome,implicating apparent differences in the intestinal metagenomic potential/function between the mother and the *** conclusion,maternal ingestion of Probio-M9 during the final weeks of gestation could deliver to the infant *** findings provided novel insights into shaping infant's gut microbiota.

关键词： Metagenomic analysis Lacticaseibacillus rhamnosus Gut microbiome Mother Infant

Low H_(2)O_(2)consumption Fenton-like catalysts for pollutant cleavage based on the construction of a dual reaction center

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Journal of Environmental sciences 2024年第11期145卷 107-116页

作者： Weixiang Liao Ziwen Zhao lai Lyu Chun Hu Fan Li key Laboratory for Water Quality and Conservation of the Pearl River Delta Ministry of EducationInstitute of Environmental Research at Greater BayGuangzhou UniversityGuangzhou 510006China key Laboratory of Drinking Water science and Technology Research Center for Eco-Environmental SciencesChinese Academy of SciencesBeijing 100085China south China Institute of Environmental sciences Ministry of Ecology and EnvironmentGuangzhou 510345China

High energy consumption has seriously hindered the development of Fenton-like reactions for the removal of refractory organic pollutants in *** solve this problem,we designed a novel Fenton-like catalyst(Cu-PAN3)by coprecipitation and carbon thermal *** catalyst exhibits excellent Fenton-like catalytic activity and stability for the degradation of various pollutants with low H_(2)O_(2)*** experimental results indicate that the dual reaction centers(DRCs)are composed of Cu-N-C and Cu-O-C bridges between copper and graphene-like carbon,which form electron-poor/rich centers on the catalyst surface.H_(2)O_(2)is mainly reduced at electron-rich Cu centers to free radicals for pollutant ***,pollutants can be oxidized by donating electrons to the electron-poor C centers of the catalyst,which inhibits the ineffective decomposition of H_(2)O_(2)at the electron-poor *** therefore significantly reduces the consumption of H_(2)O_(2)and reduces energy consumption.

关键词： Water purification Fenton-like Dual reaction centers Graphene-like carbon Low H_(2)O_(2)consumption

Optimal strategy for Aircraft Pursuit-evasion Games via self-play Iteration

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Machine Intelligence Research 2024年第3期21卷 585-596页

作者： Xin Wang Qing-lai Wei Tao Li Jie Zhang state key Laboratory of Management and Control for Complex systems Institute of AutomationChinese Academy of SciencesBeijing100190China school of Artificial Intelligence University of Chinese Academy of SciencesBeijing100049China Institute of systems Engineering Macao University of Science and TechnologyMacao999078China

In this paper,the pursuit-evasion game with state and control constraints is solved to achieve the Nash equilibrium of both the pursuer and the evader with an iterative self-play *** the condition where the Hamiltonian formed by means of Pontryagin’s maximum principle has the unique solution,it can be proven that the iterative control law converges to the Nash equilibrium ***,the strong nonlinearity of the ordinary differential equations formulated by Pontryagin’s maximum principle makes the control policy difficult to figured *** the system dynamics employed in this manuscript contains a high dimensional state vector with *** practical applications,such as the control of aircraft,the provided overload is ***,in this paper,we consider the optimal strategy of pursuit-evasion games with constant constraint on the control,while some state vectors are restricted by the function of the *** address the challenges,the optimal control problems are transformed into nonlinear programming problems through the direct collocation ***,two numerical cases of the aircraft pursuit-evasion scenario are given to demonstrate the effectiveness of the presented method to obtain the optimal control of both the pursuer and the evader.

关键词： Differential games pursuit-evasion games nonlinear control optimal control Nash equilibrium solution

Giant accessory hepatic lobe accompanied by inflammatory pseudotumor

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Hepatobiliary surgery and Nutrition 2024年第1期13卷 194-195页

作者： Hong Yang Binglin lai Department of Medical Imaging Ganzhou People’s HospitalGanzhou Hospital-Nanfang HospitalSouthern Medical UniversityGanzhouChina

A 25-year-old female was admitted to the hospital 6 months after the discovery of a liver mass during a physical *** has no abdominal pain or abdominal wall *** function and alpha-fetoprotein(AFP)levels are *** tomogr... 详细信息

关键词： admitted Liver hepatic

Cr-catalyzed allylic C(sp^(3))–H addition to aldehydes enabled by photoinduced ligand-to-metal charge transfer

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science China Chemistry 2024年第5期67卷 1589-1595页

作者： Xianrong Zeng Feng-Hua Zhang Runchen lai Xiaoyu Lin Zhaobin Wang key Laboratory of Precise synthesis of Functional Molecules of Zhejiang Province Department of ChemistrySchool of Science and Research Center for Industries of the FutureWestlake UniversityHangzhou 310030China Institute of Natural sciences Westlake Institute for Advanced StudyHangzhou 310024China key Laboratory of Precise synthesis of Functional Molecules of Zhejiang Province Instrumentation and Service Center for Molecular SciencesWestlake UniversityHangzhou 310024China

Photoinduced ligand-to-metal charge transfer(LMCT) has emerged as an effective strategy for synthesizing organic molecules in a sustainable manner. However, the majority of existing reports on selective C(sp^(3))–H bond functionalization via photoinduced LMCT focus on the use of late transition metals or rare-earth metals for radical additions or cross-couplings. In contrast, the utilization of photoinduced LMCT with 3d early transition metals poses a significant challenge. Herein, we describe an unprecedented approach to allylic C(sp^(3))–H addition to aldehydes, employing chromium(Cr) complexes as catalysts through visible-light-induced LMCT. By investigating the reaction pathway through various mechanistic studies, including radical trapping, kinetic isotope effect(kIE) analysis, and transient absorption spectroscopy, valuable insights have been gained. The proposed mechanism suggests the intermediacy of bromine radicals through homolysis of the Cr–Br bond. Notably, this protocol expands our understanding of the photochemical properties of earth-abundant Cr complexes.

关键词： Cr catalysis photoinduced ligand-to-metal charge transfer hydrogen-atom transfer carbonyl addition

Dispersion effect of nano-structure pyrolytic carbon on mechanical,electrical,and microstructural characteristics of cement mortar composite

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International Journal of smart and Nano Materials 2024年第3期15卷 534-578页

作者： N.k.karthikeyan s.Elavenil school of Civil Engineering Vellore Institute of TechnologyChennaiIndia

In material science,converting waste into nanomaterials by green technologies highlights the interest in producing sus-tainable carbon nanomaterial(sCN).This study first-ever uti-lized tyre-char as a Nano-structure Pyrolytic Carbon(NsPC)to develop electrically conductive *** other car-bon nanomaterials,the efficiency of NsPC particle as an sCN in developing electrically conductive composites was investi-gated in terms of dispersion,mechanical,water absorption,electrical resistivity,and *** results of sedi-mentation and zeta potential(-19 mV)showed the excellent dispersion of NsPC particle in water with the combined effect of superplasticizer and *** compressive(40.37%)and flexural strength(10.76%)than that of plain cement mortar composite(CMC)is achieved with 2 wt.%and 1.5 wt.%of NsPC particle,*** water absorption rate and volume of permeable voids were reduced,exhibiting less *** percolation zone of AC and DC resis-tivity of NsPC composite ranges between 1 and 2 wt.%,and the established percolation threshold is at 2 wt.%.XRD analysis showed C-s-H formation consistently increased with curing age,and HR-sEM with EDAX analysis exhibits the dense micro-structure and well-distributed NsPC particle at the *** experimental outcomes significantly enhanced the relia-bility and provided a framework for tailoring NsPC particle as sCN for developing electrically conductive composite.

关键词： sustainable nanomaterial dispersion mechanical properties electrical resistivity microstructure analysis