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On the effect of pitch and yaw angles in oblique impacts of smallcaliber projectiles

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Defence Technology（防务技术） 2024年第1期31卷 73-94页

作者： Teresa Fras French-German research institute of Saint-Louis(ISL) Saint-LouisFrance

A terminal ballistic analysis of the effects of 7.62 mm × 51 AP P80 rounds on inclined high-strength armor steel plates is the focus of the presented *** findings of an instrumented ballistic testing combined with 3D advanced numerical simulations performed using the IMPETUS Afea? software yielded the *** experimental verification proved that slight differences in the pitch-andyaw angles of a projectile upon an impact caused different damage types to the projectile’s *** residual velocities predicted numerically were close to the experimental values and the calculated core deviations were in satisfactory agreement with the experimental *** extended matrix of the core deviation angles with combinations of pitch-and-yaw upon impact angles was subsequently built on the basis of the numerical *** presented experimental and numerical investigation examined thoroughly the influence of the initial pitch and yaw angles on the after-perforation projectile’s performance.

关键词： Ballistic impact Small-caliber projectile Pitch and yaw impact angles Shadowgraphy IMPETUS Afea Numerical simulations

Impact wear properties of dissimilar joints between bainitic frogs and pearlite rails

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Journal of Iron and Steel research(International) 2024年第1期31卷 275-287页

作者： Pin-yong Zeng Chun-guang Zuo Xiao-yu Zhang Wei Li Tribology research institute Southwest Jiaotong UniversityChengdu610031SichuanChina

The impact wear behavior and damage mechanism of dissimilar welded joints between U26Mn frog and U75 V rail before and after normalizing treatment were studied by cyclic impact *** experiment indicated that the impact wear volume of the joints increased with the increasing number of impact *** main wear mechanisms include pitting wear,mild fatigue wear,delamination wear,and fatigue wear,and plastic deformation was the primary impact wear *** them,fatigue wear had the greatest influence on wear volume,while other wear mechanisms had limited *** impact wear resistance of the base material was better than that of the heat-affected *** treatment was beneficial to improving the impact wear resistance of welded joints owing to its effect to promote pearlite recovery,grain refinement,and uniform distribution of *** martensite generated in the rail welded joints aggravated the impact wear damage to the materials,which should be avoided.

关键词： Dissimilar welded joint Impact wear Bainitic steel Damage mechanism Wear rate

Synergistic effect and heterointerface engineering of cobalt/carbon nanotubes enhancing electromagnetic wave absorbing properties of silicon carbide fibers

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Nano research 2024年第9期17卷 8479-8486页

作者： Zixiang Zhao Zheyipei Ma Zizhao Ding Yanqiong Liu Mingwei Zhang Chao Jiang institute of Powder Metallurgy research Central South UniversityChangsha 410083China

To improve the synergistic effect between dielectric and magnetic loss is a practical and effective way in optimizing electromagnetic wave absorbing *** composites of metal particles and carbon ligands derived from metal organic frameworks have gained wide *** this study,Co particles and multiwalled carbon nanotubes(CNT)were successfully synthesized covering the surface of silicon carbide(SiC)fibers,and the morphology,interfaces and electromagnetic wave absorption performance were *** sample SiC@Co/CNT,the minimum reflection loss value can reach-70.22 dB at 11.21 GHz with the thickness of 2.12 *** effective absorbing bandwidth can reach up to 6.03 GHz with the thickness of 1.71 mm,which covers the entire Ku *** brings more interfaces between Co particles and CNTs as well as SiC fibers and Co/C *** interfacial polarization has been hugely enhanced,and the microwave absorbing properties have been *** article reports on the impedance matching of magnetic and non-magnetic components and the heterointerface engineering,which can be effective strategy and inspiration to illustrate the relationship between components,structures and functions of electromagnetic wave absorbing materials.

关键词： metal organic frameworks Co nanocrystals carbon nanotubes Schottky heterointerfaces synergistic effect

Effect of Fe Addition on Dehydrogenation Performance of Methylcyclohexance over Pt/Al_(2)O_(3)

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China Petroleum Processing & Petrochemical Technology 2024年第1期26卷 12-18页

作者： Tong Fengya Tian Hao Wang Hao Miao Changxi Song Lei Shanghai research institute of Petrochemical Technology SINOPEC Shanghai201208

Catalysts with varying Fe contents were prepared using a sequential impregnation method to investigate the effects of Fe addition on the physicochemical properties of Pt/Al_(2)O_(3) and their performance in methylcyclohexane(MCH)*** results demonstrated that the addition of Fe to Pt/Al_(2)O_(3) enhanced the electron density of Pt and improved catalytic activity,while exhibiting negligible influence on the catalytic selectivity for *** the Fe content was 0.057%,the catalyst exhibited the highest MCH consumption rate,which was approximately two times higher than that of the catalyst without ***,the incorporation of Fe inhibited the formation of coke and reduced the quantity of coke deposits on the catalyst,thereby improving its catalytic ***,Fe shows promise as a prospective secondary element for Pt/Al_(2)O_(3) to enhance the MCH dehydrogenation performance.

关键词： methylcyclohexane dehydrogenation hydrogen storage deactivation Fe addition

Assembly of functional carboxymethyl cellulose/polyethylene oxide/anatase TiO_(2) nanocomposites and tuning the dielectric relaxation, optical, and photoluminescence performances

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Journal of Semiconductors 2024年第7期45卷 26-38页

作者： Asmaa M.Ismail Abeer A.Reffaee Fawzy G.El Desouky Spectroscopy Department Physics Research InstituteNational Research CentreGizaCairo 12622Egypt Microwave Physics and Dielectrics Department National Research CentreDokkiCairoEgypt Solid State Physics Department Physics Research InstituteNational Research CentreGizaCairo 12622Egypt

Nanocomposite films consisting of carboxymethyl cellulose,polyethylene oxide(CMC/PEO),and anatase titanium diox-ide(TO)were produced by the use of sol-gel and solution casting ***2 nanocrystals were effectively incorporated into CMC/PEO polymers,as shown by X-ray diffraction(XRD)and attenuated total reflectance fourier transform infrared(ATR-FTIR)*** roughness growth is at high levels of TO nanocrystals(TO NCs),which means increasing active sites and defects in CMC/*** differential scanning calorimetry(DSC)thermograms,the change in glass transition temperature(Tg)val-ues verifies that the polymer blend interacts with TO *** increment proportions of TO NCs have a notable impact on the dielectric performances of the nanocomposites,as *** electrical properties of the CMC/PEO/TO nanocomposite undergo significant *** nanocomposite films exhibit a red alteration in the absorption edge as the concentration of TO NCs increases in the polymer *** decline in the energy gap is readily apparent as the weight percentage of TO NCs *** photoluminescence(PL)emission spectra indicate that the sites of the luminescence peak maximums show slight variation;peaks get wider,while their intensities decrease dramatically as the concentration of TO *** nanocomposite materials show potential for multifunctional applications including optoelectronics,antireflection coatings,pho-tocatalysis,light emitting diodes,and solid polymer electrolytes.

关键词： anatase TiO_(2) CMC/PEO nanocomposites optical photoluminescent electrical optoelectronics

An impact sensitivity assessment method of spacecraft based on virtual exterior wall

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Defence Technology（防务技术） 2024年第1期31卷 142-157页

作者： Runqiang Chi Yuyan Liu Diqi Hu Baojun Pang Hypervelocity Impact research Center Harbin Institute Of TechnologyHarbin150080China

The impact sensitivity assessment of spacecraft is to obtain the probability of spacecraft encountering the OD/M(orbital debris or meteoroid),which is a prerequisite for survivability assessment of on-orbit *** impact sensitivity assessment method of spacecraft based on virtual exterior wall was proposed to improve the computational *** method eliminates determination of the outermost surface elements of the spacecraft before generating the debris rays,which are assumed to originate from a non-concave virtual wall that completely wraps the *** Dist Mesh method was adopted for the generating of the virtual wall to ensure its mesh *** influences of the sizes,mesh densities,shapes of the virtual wall on the efficiency and accuracy were considered to obtain the best combination of the size and mesh density of the wall and *** results of this method were compared with those of S3DE(Survivability of Spacecraft in Space Debris Environment),BUMPER,MDPANTO,ESABASE2/Debris to verify the feasibility of the *** PCHIP(Piecewise Cubic Hermite Interpolating Polynomial)was used to fit the size *** relationship of the space debris to acquire the impact probability of OD/M with arbitrary size on the spacecraft.

关键词： Sensitivity OD/M Spacecraft Virtual exterior wall

Ultrahard X-ray multifunctional application beamline at the SSRF

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Nuclear Science and Techniques 2024年第6期35卷 14-25页

作者： Ke Yang Zhao-Hui Dong Chun-Yin Zhou Zi-Long Zhao Dong-Xu Liang Sai-Chao Cao Ai-Guo Li Shanghai Advanced research institute Chinese Academy of SciencesShanghai 201210China

The ultrahard X-ray multifunctional application beamline(BL12SW)is a phase-II beamline project at the Shanghai Syn-chrotron Radiation *** primary X-ray techniques used at the beamline are high-energy X-ray diffraction and imaging using white and monochromatic *** main scientific objectives of ultrahard X-ray beamlines are focused on two research *** is the study of the structural properties of Earth’s interior and new materials under extreme high-temperature and high-pressure conditions,and the other is the characterization of materials and processes in near-real service *** beamline utilizes a superconducting wiggler as the light source,with two diamond windows and SiC discs to filter out low-energy light(primarily below 30 keV)and a Cu filter assembly to control the thermal load entering the subsequent optical *** beamline is equipped with dual *** first was a meridional bending Laue monochromator cooled by liquid nitrogen,achieving a full-energy coverage of 30-162 *** second was a sagittal bending Laue monochromator installed in an external building,providing a focused beam in the horizontal direction with an energy range of 60-120 *** were four experimental hutches:two large-volume press experimental hutches(LVP1 and LVP2)and two engineering material experimental hutches(ENG1 and ENG2).Each hutch was equipped with various near-real service conditions to satisfy different *** example,LVP1 and LVP2 were equipped with a 200-ton DDIA press and a 2000-ton dual-mode(DDIA and Kawai)press,***1 and ENG2 provide in situ tensile,creep,and fatigue tests as well as high-temperature *** June 2023,the BL12SW has been in trial *** is expected to officially open to users by early 2024.

关键词： Shanghai Synchrotron Radiation Facility Ultrahard X-ray High energy diffraction High energy imaging Engineering materials Earth science

Glucagon-like peptide 1 receptor activation:anti-inflammatory effects in the brain

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Neural Regeneration research 2024年第8期19卷 1671-1677页

作者： Yolanda Diz-Chaves Zainab Maastor Carlos Spuch José Antonio Lamas Lucas C.González-Matías Federico Mallo Biomedical research Centre(CINBIO) Laboratory of EndocrinologyUniversity of VigoGalicia Sur Health Research InstituteVigoSpain Translational Neuroscience research Group Galicia Sur Health Research InstituteCIBERSAMHospitalÁlvaro CunqueiroSala InvestigaciónEstrada Clara CampoamorVigoSpain Biomedical research Centre(CINBIO) Laboratory of NeuroscienceUniversity of VigoGalicia Sur Health Research InstituteVigoSpain

The glucagon-like peptide 1 is a pleiotropic hormone that has potent insulinotropic effects and is key in treating metabolic diseases such as diabetes and ***-like peptide 1 exerts its effects by activating a membrane receptor identified in many tissues,including diffe rent brain ***-like peptide 1 activates several signaling pathways related to neuroprotection,like the support of cell growth/survival,enhancement promotion of synapse formation,autophagy,and inhibition of the secretion of proinflammatory cytokines,microglial activation,and apoptosis during neural *** glial cells,including astrocytes and microglia,maintain metabolic homeostasis and defe nse against pathogens in the central nervous *** brain insult,microglia are the first cells to respond,followed by reactive *** activated cells produce proinflammato ry mediators like cytokines or chemokines to react to the ***,under these circumstances,mic roglia can become chro nically inflammatory by losing their homeostatic molecular signature and,consequently,their functions during many *** processes promote the development of neurological disorders and influence their pathological evolution:like the formation of protein aggregates,the accumulation of abnormally modified cellular constituents,the formation and release by injured neurons or synapses of molecules that can dampen neural function,and,of critical impo rtance,the dysregulation of inflammato ry control *** glucagonlike peptide 1 receptor agonist emerges as a critical tool in treating brain-related inflammatory pathologies,restoring brain cell homeostasis under inflammatory conditions,modulating mic roglia activity,and decreasing the inflammato ry *** review summarizes recent advances linked to the anti-inflammato ry prope rties of glucagon-like peptide 1 receptor activation in the brain related to multiple sclerosis,Alzheimer’s disease,Parkins

关键词： astrocytes brain glucagon-like peptide 1 receptor inflammation microglia

Small mammal community composition impacts bank vole (Clethrionomys glareolus) population dynamics and associated seroprevalence of Puumala orthohantavirus

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Integrative Zoology 2024年第1期19卷 52-65页

作者： Felicitas Maria BUJNOCH Daniela REIL Stephan DREWES Ulrike MROSENFELD Rainer G.ULRICH Jens JACOB Christian IMHOLT Julius Kühn-institute Federal Research Centre for Cultivated PlantsInstitute for Epidemiology and Pathogen DiagnosticsRodent ResearchMünsterGermany University of Münster Institute for Evolution and BiodiversityMünsterGermany Friedrich-Loeffler-Institut Federal Research Institute for Animal HealthInstitute of Novel and Emerging Infectious DiseasesGreifswald-Insel RiemsGermany

Rodents are important reservoirs for zoonotic pathogens that cause diseases in *** is hypoth-esized to be closely related to pathogen prevalence through multiple direct and indirect *** example,the presence of non-host species can reduce contact rates of the main reservoir host and thus reduce the risk of transmission(“dilution effect”).In addition,an overlap in ecological niches between two species could lead to increased interspecific competition,potentially limiting host densities and reducing density-dependent pathogen transmission *** this study,we investigated the relative impact of population-level regulation of direct and indirect drivers of the prevalence of Puumala orthohantavirus(PUUV)in bank voles(Clethrionomys glareolus)during years with high *** compiled data on small mammal community composition from four regions in Germany between 2010 and *** equation modeling revealed a strong seasonality in PUUV control mechanisms in bank *** abundance of shrews tended to have a negative relationship with host abundance,and host abundance positively influenced PUUV seroprevalence,while at the same time increasing the abundance of competing non-hosts like the wood mouse(Apodemus sylvaticus)and the yellow-neckedfield mouse(Apodemusflavicollis)were associated with reduced PUUV seroprevalence in the *** results indicate that for PUUV in bank voles,dilution is associated with increased interspecific *** pressures leading to the decline of Apodemus *** a specific habitat could lead to the amplification of mechanisms promoting PUUV transmission within the host populations.

关键词： bank vole biodiversity Puumala orthohantavirus small mammals