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Chinese Chemical Letters 2024年第4期35卷 452-456页

作者： Yikun Wang Qiaomei Chen Shijie Liang Dongdong Xia Chaowei Zhao Christopher R.mcneill Weiwei Li Beijing Advanced Innovation Center for Soft Matter Science and engineering&State Key Laboratory of Organic-Inorganic Composites Beijing University of Chemical TechnologyBeijing 100029China Institute of Applied Chemistry Jiangxi Academy of SciencesNanchang 330096China Department of Materials Science and engineering Monash UniversityWellington RoadClaytonVictoria 3800Australia

The photovoltaic properties of double-cable conjugated polymers are significantly influenced by the length of the alkyl linkers that connect donor backbones and acceptor side units. In this study, a series of 2-(3-oxo-2,3-dihydroinden-1-ylidene)malononitrile(IC)-based double-cable polymers with alkyl linkers ranging from C_8H_(16)to C_(16)H_(32)(Px, x = 8, 10, 12, 14, 16) were synthesized for single-component organic solar cells(SCOSCs). Among these, the linker length x = 12(P12) is found to optimize the power conversion efficiencies(PCes) in SCOSCs. Specifically, PCes increase from P8 to P12 and then decline from P12to P16. Detailed investigations of optical absorption, charge transport, and morphology provide insights into the underlying factors contributing to these PCe variations. The findings indicate that the exceptional photovoltaic properties observed in P12 can be attributed to three key factors: A delicate balance between enhanced charge separation facilitated by the increased spacer length and reduced crystallinity resulting from longer spacers, higher charge mobilities, and well-balanced hole/electron transport characteristics. This study highlights the critical role of linker length in determining the photovoltaic properties of double-cable conjugated polymer-based SCOSCs and offers valuable guidance for the design of novel double-cable conjugated polymers.

关键词： Single-component organic solar cells Double-cable conjugated polymers Photovoltaic properties Alkyl linkers

The effects of local variations in conditions on carbon storage and release in the continental mantle

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National Science Review 2024年第6期11卷 22-36页

作者： Stephen f.foley Chunfei Chen Dorrit e.Jacob School of Natural Sciences Macquarie University Research School of earth Sciences Australian National University State Key Laboratory of Geological Processes and Mineral Resources School of Earth Sciences China University of Geosciences

Recent advances indicate that the amount of carbon released by gradual degassing from the mantle needs to be revised upwards, whereas the carbon supplied by plumes may have been overestimated in the *** in rock types and oxidation state may be very local and exert strong influences on carbon storage and release mechanisms. Deep subduction may be prevented by diapirism in thick sedimentary packages,whereas carbonates in thinner sequences may be subducted. Carbonates stored in the mantle transition zone will melt when they heat up, recognized by coupled stable isotope systems(e.g. Mg, Zn, Ca). There is no single ‘mantle oxygen fugacity’, particularly in the thermal boundary layer(TBL) and lowermost lithosphere, where very local mixtures of rock types coexist. Carbonate-rich melts from either subduction or melting of the uppermost asthenosphere trap carbon by redox freezing or as carbonate-rich dykes in this zone. Deeply derived, reduced melts may form further diamond reservoirs, recognized as polycrystalline diamonds associated with websteritic silicate minerals. Carbon is released by either edge-driven convection,which tears sections of the TBL and lower lithosphere down so that they melt by a mixture of heating and oxidation, or by lateral advection of solids beneath rifts. Both mechanisms operate at steps in lithosphere thickness and result in carbonate-rich melts, explaining the spatial association of craton edges and carbonate-rich magmatism. High-pressure experiments on individual rock types, and increasingly on reactions between rocks and melts, are fine-tuning our understanding of processes and turning up unexpected results that are not seen in studies of single rocks. future research should concentrate on elucidating local variations and integrating these with the interpretation of geophysical signals. Global concepts such as average sediment compositions and a uniform mantle oxidation state are not appropriate for small-scale processes; an increa

关键词： lithospheric mantle carbonate melts deep carbon cycle craton destruction continental rifts

Converting TRex-RGB green-channel data to 557.7 nm auroral intensity:Methodology and initial results

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earth and Planetary Physics 2024年第1期8卷 258-274页

作者： Jun Liang D.M.Gillies e.Spanswick e.f.Donovan University of Calgary CalgaryT2N 1N4Canada

The recently deployed Transition Region explorer(TRex)-RGB(red-green-blue)all-sky imager(ASI)is designed to capture“true color”images of the aurora and *** the 557.7 nm green line is usually the brightest emission line in visible auroras,the green channel of a TRex-RGB camera is usually dominated by the 557.7 nm *** this rationale,the TRex mission does not include a specific 557.7 nm imager and is designed to use the RGB green-channel data as a proxy for the 557.7 nm *** this study,we present an initial effort to establish the conversion ratio or formula linking the RGB green-channel data to the absolute intensity of 557.7 nm auroras,which is crucial for quantitative uses of the RGB *** illustrate two approaches:(1)through a comparison with the collocated measurement of green-line auroras from the TRex spectrograph,and(2)through a comparison with the modeled green-line intensity according to realistic electron precipitation flux measurements from low-earth-orbit satellites,with the aid of an auroral transport *** demonstrate the procedures and provide initial results for the TRex-RGB ASIs at the Rabbit Lake and Lucky Lake *** RGB response is found to be *** conversion ratios or formulas between RGB green-channel data and the green-line auroral intensity are given and can be applied immediately by TRex-RGB data *** methodology established in this study will also be applicable to the upcoming SMILe ASI mission,which will adopt a similar RGB camera system in its deployment.

关键词： TRex RGB green-line aurora auroral transport model

All-electron basis sets for H to Xe specific for ZORA calculations:Applications in atoms and molecules

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Chinese Physics B 2024年第8期33卷 238-246页

作者： C.S.Gomes f.e.Jorge A.Canal Neto Departamento de fisica Universidade Federal do Espirito Santo29075-910 VitoriaESBrazil Departamento de fisica Instituto de Ciencias Exatas e BiologicasUniversidade Federal de Ouro Preto Campus Universitario Morro do Cruzeiro35402-136 Ouro PretoMGBrazil

A segmented basis set of quadruple zeta valence quality plus polarization functions(QZP)for H through Xe was developed to be used in conjunction with the ZORA *** set was augmented with diffuse functions to describe electrons farther away from the nuclei *** the ZORA-CCSD(T)/QZP-ZORA theoretical model,atomic ionization energies and bond lengths,harmonic vibrational frequencies,and atomization energies of some molecules were *** addition of core-valence corrections has been shown to improve the agreement between theoretical and experimental results for molecular *** atomization energies,a similar observation emerges when considering spin-orbit *** the augmented QZP-ZORA set,static mean dipole polarizabilities of a set of atoms were calculated and compared with previously published recommended and experimental *** evaluations of the ZORA and Douglas–Kroll–Hess Hamiltonians were made for each property studied.

关键词： QZP-ZORA and AQZP-ZORA basis sets elements from H to Xe CCSD(T)method atomic and molecular properties

effects of dust controls on respirable coal mine dust composition and particle sizes:case studies on auxiliary scrubbers and canopy air curtain

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International Journal of Coal Science & Technology 2024年第3期11卷 86-101页

作者： f.Animah C.Keles W.R.Reed e.Sarver Department of Mining and Minerals engineering Virginia Polytechnic Institute&State UniversityBlacksburgVAUSA National Institute of Occupational Safety and Health(NIOSH) PittsburghPAUSA

Control of dust in underground coal mines is critical for mitigating both safety and health *** decades,the National Institute of Occupational Safety and Health(NIOSH)has led research to evaluate the effectiveness of various dust control technologies in coal *** studies have included the evaluation of auxiliary scrubbers to reduce respirable dust downstream of active mining and the use of canopy air curtains(CACs)to reduce respirable dust in key operator *** detailed dust characterization was not a focus of such studies,this is a growing area of *** preserved filter samples from three previous NIOSH studies,the current work aims to explore the effect of two different scrubbers(one wet and one dry)and a roof bolter CAC on respirable dust composition and particle size *** this,the preserved filter samples were analyzed by thermogravimetric analysis and/or scanning electron microscopy with energy dispersive *** indicate that dust composition was not appreciably affected by either scrubber or the ***,the wet scrubber and CAC appeared to decrease the overall particle size *** an effect of the dry scrubber was not consistently observed,but this is probably related to the particular sampling location downstream of the scrubber which allowed for significant mixing of the scrubber exhaust and other return *** from the insights gained with respect to the three specific dust control case studies revisited here,this work demonstrates the value of preserved dust samples for follow-up investigation more broadly.

关键词： Respirable dust Dust control SeM–eDX Scrubber Canopy air curtain Silica

Modelling the brittle rock failure by the quaternion-based bonded-particle model in DeM

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Rock Mechanics Bulletin

Rock Mechanics Bulletin 2024年第2期3卷 87-95页

作者： Tao Zhao Philip e.f.Collins Department of Civil and environmental engineering Brunel University LondonLondonUB83PHUnited Kingdom

This paper presents an investigation of brittle rock failure by the quaternion-based bonded-particle model in discrete element method(DeM).Unlike traditional approaches that utilize euler angles or rotation matrices,this model employs unit quaternions to represent the spatial rotations of *** method simplifies the rep-resentation of 3D rotations,providing a more intuitive framework for modelling complex interactions in granular *** numerical model was validated by the uniaxial compression tests on rock,with good agreement with well-documented experimental data in terms of the rock uniaxial compression strength(UCS)and failure *** loading,the rock sample demonstrated a linear-elastic response at an axial strain of smaller than 0.45%.However,as internal bond breakage accumulated,this linear relationship weakened,and the stress-strain curve began to deviate from its initial linear *** bond breakage and the overall deformation of the rock were primarily controlled by the shear bonding *** UCS was achieved at an axial strain of 0.625%,at which point the internal shear bonding force chains were predominantly aligned *** brittle failure occurred when the internal damage of solids nucleated to form an interconnected failure plane,accompanied by a sharp rise in the internal damage *** area of failure plane increased with the loading strain rate,gradually transforming the failure pattern from the local damage to a complete fragmentation.

关键词： Brittle failure Quaternion DeM bonded model Uniaxial compression test Rate dependent Internal damage

Comparisons of oxbow lake fish assemblages in relation to bigheaded carp establishment in the lower White River, Arkansas

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ecological Processes 2024年第1期13卷 188-205页

作者： Michael A.eggleton Cody J.Salzmann Joseph e.Kaiser Shannon C.f.Smith Department of Aquaculture and fisheries University of Arkansas at Pine Bluff Arkansas Game and fish Commission Virginia Institute of Marine Science

Background Since the late 1990s, bigheaded carps(largely silver carp [Hypophthalmichthys molitrix] but also bighead carp [H. nobilis]) have established throughout the lower Mississippi River basin. Using previously studied oxbow lakes in the lower White River basin, Arkansas, we compared current(2017, “post-carp” establishment) fish assemblages to historical(2002, “pre-carp” establishment) fish assemblages. fish assemblages were comprehensively assessed using multiple gears, including boat electrofishing, mini-fyke nets, and experimental small-mesh gill *** T-tests suggested that fish assemblage indices of richness, diversity, evenness, and dominance were often greater(P e post-carp period as reflected by boat electrofishing and experimental gill nets. However, all indices were generally similar(P > 0.05) between the pre-carp and post-carp period with fish assemblages depicted using mini-fyke nets. Nonmetric multidimensional scaling analyses indicated that fish assemblages differed structurally between pre-carp and post-carp periods. Assemblage differences were linked to both small and large abundance changes for more than 20 species. Abundances of gizzard shad(Dorosoma cepedianum), emerald shiner(Notropis atherinoides), pugnose minnow(Opsopoeodus emiliae), crappies(Pomoxis spp.), bluegill(Lepomis macrochirus), orangespotted sunfish(L. humilis), and yellow bass(Morone mississippiensis) declined between the pre-carp and postcarp periods. Conversely, abundances of weed shiner(N. texanus), pallid shiner(Hybopsis amnis), longear sunfish(L. megalotis), buffalofishes(Ictiobus spp.), and gars(Lepisosteus spp.) generally increased during the same *** Although not possible to conclude assemblage shifts were entirely related to bigheaded carps due to the absence of an appropriate reference system where carps did not establish, the wide establishment of these carps is one of the most pervasive changes to have occurred in the lower White

关键词： Bigheaded carp Silver carp Aquatic nuisance species fish assemblage Oxbow lake Large river

A Hybrid Cybersecurity Algorithm for Digital Image Transmission over Advanced Communication Channel Models

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Computers, Materials & Continua 2024年第4期79卷 201-241页

作者： Naglaa f.Soliman fatma e.fadl-Allah Walid el-Shafai Mahmoud I.Aly Maali Alabdulhafith fathi e.Abd el-Samie Department of Information Technology College of Computer and Information SciencesPrincess Nourah bint Abdulrahman UniversityP.O.Box 84428Riyadh11671Saudi Arabia Department of electronics and Communications Faculty of EngineeringZagazig UniversityZagazig44519Egypt Security engineering Lab Computer Science DepartmentPrince Sultan UniversityRiyadh11586Saudi Arabia Department of electronics and electrical Communications engineering Faculty of Electronic EngineeringMenoufia UniversityMenouf32952Egypt

The efficient transmission of images,which plays a large role inwireless communication systems,poses a significant challenge in the growth of multimedia ***-quality images require well-tuned communication *** Single Carrier frequency Division Multiple Access(SC-fDMA)is adopted for broadband wireless communications,because of its low sensitivity to carrier frequency offsets and low Peak-to-Average Power Ratio(PAPR).Data transmission through open-channel networks requires much concentration on security,reliability,and *** data need a space away fromunauthorized access,modification,or *** requirements are to be fulfilled by digital image watermarking and *** paper ismainly concerned with secure image communication over the wireless SC-fDMA systemas an adopted communication *** introduces a robust image communication framework over SC-fDMA that comprises digital image watermarking and encryption to improve image security,while maintaining a high-quality reconstruction of images at the receiver *** proposed framework allows image watermarking based on the Discrete Cosine Transform(DCT)merged with the Singular Value Decomposition(SVD)in the so-called DCT-SVD *** addition,image encryption is implemented based on chaos and DNA *** encrypted watermarked images are then transmitted through the wireless SC-fDMA *** linearMinimumMean Square error(MMSe)equalizer is investigated in this paper to mitigate the effect of channel fading and noise on the transmitted *** subcarrier mapping schemes,namely localized and interleaved schemes,are compared in this *** study depends on different channelmodels,namely PedestrianAandVehicularA,with a modulation technique namedQuadratureAmplitude Modulation(QAM).extensive simulation experiments are conducted and introduced in this paper for efficient transmission of encrypted watermarked *** addition,different variants of SC-fDMA bas

关键词： Cybersecurity applications image transmission channel models modulation techniques watermarking and encryption

Control and vibration analyses of a sandwich doubly curved micro-composite shell with honeycomb,truss,and corrugated cores based on the fourth-order shear deformation theory

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Applied Mathematics and Mechanics(english edition) 2024年第10期45卷 1773-1790页

作者： f.SHIRDeLAN M.MOHAMMADIMeHR f.BARGOZINI Department of Solid Mechanics Faculty of Mechanical EngineeringUniversity of KashanKashan 87317-53153Iran

Curved shells are increasingly utilized in applied engineering due to their shared characteristics with other sandwich structures,flexibility,and attractive ***,the inability of controlling and regulating vibrations and destroying them afterward is a challenge to *** this paper,the curve shell equations and a linear quadratic regulator are adopted for the state feedback design to manage the structure vibrations in state space forms.A five-layer sandwich doubly curved micro-composite shell,comprising two piezoelectric layers for the sensor and actuator,is modeled by the fourth-order shear deformation *** core(honeycomb,truss,and corrugated)is analyzed for the bearing of transverse shear *** results show that the honeycomb core has a greater effect on the *** the parameters related to the core and the weight percentage of graphene increase,the frequency *** uniform distribution of graphene platelets results in the lowest natural frequency while the natural frequency ***,without taking into account the piezoelectric layers,the third-order shear deformation theory(TSDT)and fourth-order shear deformation theory(fOSDT)align ***,when the piezoelectric layers are incorporated,these two theories diverge significantly,with the frequencies in the fOSDT being lower than those in the TSDT.

关键词： vibration and control doubly curved shell micro-composite honeycomb truss corrugate core