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Merging bound states in the continuum in an open acoustic resonator

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Science China(Physics,Mechanics & Astronomy) 2025年第1期Mechanics & Astronomy) .卷 124-131页

作者： Lujun Huang Bin Jia Artem S.Pilipchuk Sibo Huang Chen Shen Almas f.Sadreev Yong Li Andrey E.Miroshnichenko School of Physics and Electronic Sciences East China Normal University Institute of Acoustics Tongji University L.V.Kirensky Institute of Physics Department of Mechanical Engineering Rowan University School of Engineering and Technology University of New South Wales at Canberra

Bound states in the continuum （BICs） are perfectly localized resonances despite embedding in the continuum ***,an isolated BIC is very sensitive to the structure ***,we report merging acoustic BICs in a single open resonator,robust against the structure *** find that both symmetry-protected BIC and friedrich-Wintgen BIC are sustained in a single coupled waveguide-resonator *** varying the height and length of the resonator,these two BICs move toward each other and merge into a single one at a critical *** to an individual BIC,the merged BIC is robust against fabrication error because its Q-factor is proportional to ΔL-4,whereΔL embodies the structure *** essence of this extraordinary phenomenon is perfectly explained by the two-and three-level approximations of the effective nonHermitian ***,we present direct experimental demonstrations of the moving and merging of BICs in a coupled 3D waveguide-resonator,which are evidenced by the vanishing of the linewidth of fano resonance in the transmission *** results may find exciting applications in designing high-quality acoustic sources,sensors and filters.

关键词： acoustic resonances bound state in the continuum high-Q resonances

Complement-dependent neuroinflammation in spinal cord injury:from pathology to therapeutic implications

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Neural Regeneration Research 2025年第5期20卷 1324-1335页

作者： Hassan Saad Bachar El Baba Ali Tfaily firas Kobeissy Juanmarco Gutierrez Gonzalez Daniel Refai Gerald R.Rodts Christian Mustroph David Gimbel Jonathan Grossberg Daniel L.Barrow Matthew f.Gary Ali M.Alawieh Department of Neurosurgery Emory University School of MedicineAtlantaGAUSA Department of Neurology Yale UniversityNew HavenCTUSA Center for Neurotrauma Multiomics&Biomarkers(CNMB)Morehouse School of MedicineAtlantaGAUSA

Spinal cord injury remains a major cause of disability in young adults,and beyond acute decompression and rehabilitation,there are no pharmacological treatments to limit the progression of injury and optimize recovery in this *** the thorough investigation of the complement system in triggering and propagating cerebral neuroinflammation,a similar role for complement in spinal neuroinflammation is a focus of ongoing *** this work,we survey the current literature investigating the role of complement in spinal cord injury including the sources of complement proteins,triggers of complement activation,and role of effector functions in the *** study relevant data demonstrating the different triggers of complement activation after spinal cord injury including direct binding to cellular debris,and or activation via antibody binding to damage-associated molecular *** effector functions of complement have been implicated in spinal cord injury,and we critically evaluate recent studies on the dual role of complement anaphylatoxins in spinal cord injury while emphasizing the lack of pathophysiological understanding of the role of opsonins in spinal cord *** this pathophysiological review,we systematically review the different translational approaches used in preclinical models of spinal cord injury and discuss the challenges for future translation into human *** review emphasizes the need for future studies to dissect the roles of different complement pathways in the pathology of spinal cord injury,to evaluate the phases of involvement of opsonins and anaphylatoxins,and to study the role of complement in white matter degeneration and regeneration using translational strategies to supplement genetic models.

关键词： complement neuroinflammation neuroplasticity regeneration spinal cord injury targeted therapy

Effects of Sewage Sludge Application on the Heavy Metal Content of Crested Wheatgrass （Agropyron cristatum （L.）） Gaertn

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Journal of Environmental Science and Engineering(B) 2014年第5期3卷 232-245页

作者： Hakkl Akdeniz Mehmet Ali Bozkurt Omer terzioglu Bilal Keskin fields Crops of Agricultural faculty Igdtr University Igdr 7600 Turkey fields Crops of Agricultural faculty Yiiziincii Yll University Van 65080 Turkey

This paper presents the data from two-year experiments concerning with doses of sewage sludge （0, 7, 14 and 21 ***^-1） and inorganic nitrogen doses （0, 50, 100 and 150 ***^-1） from the Municipality of Van, which is located at an altitude of 1,725 m of eastern Anatolia in Turkey. A study was conducted to assess two different N sources on sandy-silty-clay soils grown to crested wheatgrass Agropyron cristatum （L.） Gaertn, grass pasture which had been amended with sewage sludge for two years. Plant tissue and DTPA （diethylenetriamine pentaacetic acid） extractable soil nutrient were evaluated; twelve elements were analyzed in the plant tissue and six elements in the soil extract in different soil depths. The research demonstrated that the applications produced increase contents of N, P, Mg, Mn, Zn and Pb in the plant. There was a significant （P 〈 0.01） accumulation of DTPA extractable concentrations of fe, Mn, Cu, Zn and Pb in the top soil horizon. Also, sewage sludge resulted in 51 folded increase in extractable P in 0-20 cm soil horizon. However, DTPA concentrations of in soil showed that fe exhibited a significant positive correlation with the concentrations of exchangeable fractions of Mn, Cu, Zn and Pb with the correlation. Positive correlations were also observed between Cu-Mn, Mn-Zn, Mn-Pb, Cu-Zn, Cu-Pb and Zn-Pb concentrations. In the same way, plant uptake of the Mn, Zn and Pb was highly correlated with concentrations of Cu, Zn and Pb in the soil. It was concluded that sewage sludge is a valuable source of nutrient and also provides an opportunity to increase soil organic matter.

关键词： Sewage sludge crested wheatgrass nutrient heavy metal.

Leveraging ROTI map derived from Indonesian GNSS receiver network for advancing study of Equatorial Plasma Bubble in Southeast/East Asia

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Earth and Planetary Physics 2025年第1期9卷 101-116页

作者： Prayitno Abadi Ihsan N.Muafiry Teguh N.Pratama Angga Y.Putra Suraina Gatot H.Pramono Sidik T.Wibowo febrylian f.Chabibi Umar A.Ahmad Wildan P.Tresna Asnawi Research Center for Climate and Atmosphere Indonesian National Research and Innovation Agency(BRIN)BandungIndonesia School of Electrical Engineering Telkom UniversityBandungIndonesia Directorate of Laboratory Management facilities and Science and Technology Park Indonesian National Research and Innovation Agency(BRIN)PontianakIndonesia Geophysics Laboratory Master Program in PhysicsUniversitas Gadjah Mada(UGM)YogyakartaIndonesia Research Center for Space Indonesian National Research and Innovation Agency(BRIN)BandungIndonesia Indonesian Geospatial Information Agency(BIG) JakartaIndonesia Research Center for Photonics Indonesian National Research and Innovation Agency(BRIN)Tangerang SelatanIndonesia Department of Earth and Planetary Sciences Hokkaido UniversitySapporoJapan

This paper highlights the crucial role of Indonesia’s GNSS receiver network in advancing Equatorial Plasma Bubble(EPB)studies in Southeast and East Asia,as ionospheric irregularities within EPB can disrupt GNSS signals and degrade positioning *** by the Indonesian Geospatial Information Agency(BIG),the Indonesia Continuously Operating Reference Station(Ina-CORS)network comprises over 300 GNSS receivers spanning equatorial to southern low-latitude ***-CORS is uniquely situated to monitor EPB generation,zonal drift,and dissipation across Southeast *** provide a practical tool for EPB research,by sharing two-dimensional rate of Total Electron Content(TEC)change index(ROTI)derived from this *** generate ROTI maps with a 10-minute resolution,and samples from May 2024 are publicly available for further scientific *** preliminary findings from the ROTI maps of Ina-CORS are ***,the Ina-CORS ROTI maps reveal that the irregularities within a broader EPB structure persist longer,increasing the potential for these irregularities to migrate farther ***,we demonstrate that combined ROTI maps from Ina-CORS and GNSS receivers in East Asia and Australia can be used to monitor the development of ionospheric irregularities in Southeast and East *** have demonstrated the combined ROTI maps to capture the development of ionospheric irregularities in the Southeast/East Asian sector during the G5 Geomagnetic Storm on May 11,*** observed simultaneous ionospheric irregularities in Japan and Australia,respectively propagating northwestward and southwestward,before midnight,whereas Southeast Asia’s equatorial and low-latitude regions exhibited irregularities *** sharing ROTI maps from Indonesia and integrating them with regional GNSS networks,researchers can conduct comprehensive EPB studies,enhancing the understanding of EPB behavior across Southeast and East Asia and contributing significantly to ionosphe

关键词： Equatorial Plasma Bubble(EPB) GNSS receivers’network Indonesia Continuously Operating Reference Station(Ina-CORS) ionospheric map Rate of TEC change index(ROTI)map

friedrich Ackermann’s scientific research program

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Geo-Spatial Information Science 2023年第2期26卷 141-150页

作者： Wolfgang förstner Department of Photogrammetry UniversityBonnGermany

We sketch friedrich Ackermann’s research program following the concept of Imre Lakatos,with some historical key developments in the theory and application of aerotriangulation and image *** research program,with its core being statistical estimation theory,has decisively influenced photogrammetry since the 60s,is still fully alive,and a challenge for today’s methods of image *** describe(1)Lakatos’concept of a scientific research program,with its negative and positive heuristics and(2)Ackermann’s research program,clearly made explicit in his PhD,with its mathematical model,the ability to predict theoretical precision and reliability,the potential of analyzing rigorous and approximate method,and the role of *** development of aerotriangulation,later augmented by image matching techniques,is closely connected to Ackermann’s successful attempts to integrate basic research and practical applications.

关键词： friedrich Ackermann scientific research program aerotriangulation image matching role of theory and application

Acoustic radiation force and torque on a lossless eccentric layered fluid cylinder

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Chinese Physics B 2020年第11期29卷 140-145页

作者： f G Mitri Santa fe NM 87508USA

Exact analytical equations and computations for the longitudinal and transverse acoustic radiation force and axial torque components for a lossless eccentric liquid cylinder submerged in a nonviscous fluid and insonified by plane waves progressive waves(of arbitrary incidence in the polar plane)are established and computed *** modal matching method and the translational addition theorem in cylindrical coordinates are used to derive exact mathematical expressions applicable to any inner and outer cylinder sizes without any approximations,and taking into account the interaction effects between the waves propagating in the layer and those scattered from the cylindrical *** results show that longitudinal and transverse radiation force components arise,in addition to the emergence of an axial radiation torque component acting on the non-absorptive compound cylinder due to geometrical asymmetry as the eccentricity *** computations demonstrate that the axial torque component,which arises due to a geometrical asymmetry,can be positive(causing counterclockwise rotation in the polar plane),negative(clockwise rotation)or neutral(rotation cancellation)depending on the size parameter of the cylinder and the amount of ***,verification and validation of the results have been accomplished from the standpoint of energy conservation law applied to scattering,and based on the reciprocity theorem.

关键词： acoustic radiation force acoustic radiation torque non-viscous liquid eccentric cylinder

Operational feasibility study of stagnation pressure reaction control for a mid-caliber non-spinning projectile

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Defence Technology（防务技术） 2023年第6期24卷 109-121页

作者： f.Bouquet The Netherlands Organisation for Applied Scientific Research Oude Waalsdorperweg 632597 AK Den Haagthe Netherlands

Controlled,guided munitions can reduce dispersion in the shot,while providing the capability of engaging both stationary and maneuvering *** Netherlands Organisation for Applied Scientific Research has developed a fin-less control technology called Stagnation Pressure Reaction Control(SPRC)that takes stagnation pressure air and directs it sideways to control non-spinning *** a previous study,this technology was demonstrated at Mach 2 wind-tunnel conditions to achieve up to 1.5°controllable angle of incidence for a non-spinning,aerodynamically unstable projectile-like test *** an operational scenario,the decelerating projectile will experience a decline in control force while the simultaneous forward shift of the center of pressure increases the need for control ***,angles of incidence exceeding 1.5°will be experienced under realistic flight conditions,especially against maneuvering *** work addresses these challenges and presents an operational feasibility study for a practical application of SPRC in a non-spinning mid-caliber gun-launched projectile,using experiment data on control latency and force of the earlier *** illustrates the combined effect of the control-and stability dynamics and underlines the potential of an SPRC projectile as a precisionoperation *** research revealed that SPRC technology can stabilize and control the hypothesized projectile in a direct fire scenario against stationary and maneuvering targets.

关键词： Supersonic projectile feasibility study Ram air Stagnation pressure reaction control Simulation Attitude control

Radiation force and torque on a two-dimensional circular cross-section of a non-viscous eccentric layered compressible cylinder in acoustical standing waves

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Chinese Physics B 2021年第2期30卷 355-366页

作者： f G Mitri Santa fe NM 87508USA

The purpose of this study is to develop an analytical formalism and derive series expansions for the time-averaged force and torque exerted on a compound coated compressible liquid-like cylinder,insonified by acoustic standing waves having an arbitrary angle of incidence in the polar(transverse)*** host medium of wave propagation and the eccentric liquid-like cylinder are *** computations illustrate the theoretical analysis with particular emphases on the eccentricity of the cylinder,the angle of incidence and the dimensionless size parameters of the inner and coating cylindrical fluid *** method to derive the acoustical scattering,and radiation force and torque components conjointly uses modal matching with the addition theorem,which adequately account for the multiple wave interaction effects between the layer and core fluid *** results demonstrate that longitudinal and lateral radiation force components ***,an axial radiation torque component is quantified and computed for the non-absorptive compound cylinder,arising from geometrical asymmetry considerations as the eccentricity *** computational results reveal the emergence of neutral,positive,and negative radiation force and torque depending on the size parameter of the cylinder,the eccentricity,and the angle of incidence of the insonifying ***,based on the law of energy conservation applied to scattering,numerical verification is accomplished by computing the extinction/scattering energy *** results may find some related applications in fluid dynamics,particle trapping,mixing and manipulation using acoustical standing waves.

关键词： radiation force radiation torque liquid compound cylinder multiple scattering acoustical standing waves

Investigation on the influence of the initial RDX crystal size on the performance of shaped charge warheads

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Defence Technology（防务技术） 2019年第5期15卷 802-807页

作者： f.Majiet f.J.Mostert Rheinmetall Denel Munition Somerset WestSouth Africa Centre for Scientific&Industrial Research PretoriaSouth Africa

Copper lined wave shaped shaped charges of particular design and liner metallurgy were used to investigate the effect of explosive crystal size on the resultant shaped charge jet *** A3 with RDX of three different average crystal sizes,i.e.30μm,100μm and 300μm were used in the *** other parameters in the charge were kept constant and in particular,care was given to obtain consistent dimensional quality and liner microstructure,in order to prohibit the variation of other *** flash-X-ray diagnostics were used in field tests to obtain the jet parameters from multiple firings of similar *** is found that the varying crystal size of the RDX has a marginal influence in the total jet length of the ***,it is also found that there is less variation between firings in the jet parameters for jets from the charges loaded with the crystal size of 100 μm.

关键词： shaped size crystal