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Juvenile socio-sexual experience determines lifetime sperm expenditure and adult survival in a polygamous moth, Ephestiakuehniella

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Insect Science 2023年第1期30卷 232-240页

作者： Junyan Liu Xiong z.he Xia-lin zheng Yujing zhang Qiao Wang School of Agriculture and Environment Massey UniversityPalmerston NorthNew Zealand Guangxi Key Laboratory of Agric-Environment and Agric-Products Safety National Demonstration Center for Experimental Plant Science EducationCollege of AgricultureGuangxi UniversityNanningChina

Male animals often adjust their sperm investment in response to sperm competition *** date,only a few studies have investigated how juvenile sociosexual settings affect sperm production before adulthood and sperm allocation during the first ***,it is unclear whether juvenile sociosexual experience(1)determines lifetime sperm production and allocation in any animal species;(2)alters the eupyrene:apyrene sperm ratio in lifetime ejaculates of any lepidopteran insects,and(3)influences lifetime ejaculation patterns,number of matings and adult *** we used a polygamous moth,Ephestia kuehniella,to address these *** male adult emergence from juveniles reared at different density and sex ratio,we paired each male with a virgin female daily until his *** dissected each mated female to count the sperm transferred and recorded male longevity and lifetime number of *** demonstrate for the first time that males ejaculated significantly more eupyrenes and apyrenes in their lifetime after their young were exposed to juvenile *** moths continued to produce eupyrene sperm,contradicting the previous predictions for *** eupyrene:apyrene ratio in the lifetime ejaculates remained unchanged in all treatments,suggesting that the sperm ratio is critical for reproductive *** juvenile exposure to other juveniles regardless of sex ratio caused significantly shorter adult longevity and faster decline in sperm ejaculation over successive ***,males from all treatments achieved similar number of matings in their *** study provides insight into adaptive resource allocation by males in response to juvenile sociosexual environment.

关键词： juvenile experience Lepidoptera mating frequency sperm allocation sperm production sperm ratio

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Influence of Fly Ash Addition on the hydration of Portland Cement

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武汉理工大学学报 2010年第17期32卷 99-102页

作者： GENG h N ShUI z h School of Materials Science and Engineering Wuhan University of TechnologyWuhan 430070China

Influence of fly ash addition on the hydrationof Portland cement clinker,particularly at the initial stage,has been studied on the basis of measured data obtained. Fly ash,considering its active components,was added as a partial replacement of Portland cement at different water/cementitious ratios. The hydration heat was measured in a controlled environmental room of 20 ℃. Both non-evaporable water content and mineral phase were investigated. Data indicate that the amount of fly ash involved in hydration reaction is little at initial stage while it becomes more after 7 d hydration. As hydration reaction is a continuous process,chemical stress results in the disruption of stable structure on the surface of fly ash consisting of Ca,O,Si,Al,C,etc. Additionally,surface of glass beads begins to lose smooth and reacts to blend in with the paste.

关键词： hydration heat first-order and second derivative cure portland cement fly ash

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Research of Neural Network Based on Improved PSO Algorithm for Carbonation Depth Prediction of Concrete

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武汉理工大学学报 2010年第17期32卷 170-175页

作者： DAI W ShUI z h School of Materials Science and Engineering Wuhan University of TechnologyWuhan 430070China School of Economics and Management Huangshi Institution of TechnologyHuangshi 435003China

Firstly,neural network based on improved particle swarm optimization (PSO)algorithm is introduced in this paper. Based on the data collected from projects in typical areas,the concrete carbonation depth is assessed with consideration of various factors such as unit cement consumption (C),unit water consumption (W),binder material content (B),water binder ratio (W/B ),concrete strength (MPa),rapid carbonization days (D),fly ash consumption of unit volume concrete(FA),fly ash percentage of total cementitious materials (FA%),expansion agent consumption of unit volume concrete(EA),expansion agent percentage of total cementitious materials (FA%).Gaining the data from project-experiment,a model is presented to calculate and forecast carbonation depth using neural network based on improved PSO algorithm. The calculation results indicate that this algorithm accord with the prediction carbonation depth of concrete accuracy requirements and has a better convergence and generalization,worth being popularized.

关键词： PSO BP neural network concrete carbonation depth prediction

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Snap-through of an elastica under bilateral displacement control at a material point

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Acta Mechanica Sinica 2020年第3期36卷 727-734页

作者： Q.Wang h.L.zou z.C.Deng Department of Engineering Mechanics Northwestern Polytechnical UniversityXi'an 710072China

Snap-through phenomenon widely occurs for elastic systems,where the systems lose stability at critical *** snapthrough of an elastica under bilateral displacement control at a material point is studied,by regarding the whole elastica as two components,i.e.,pinned-clamped ***,stiffness-curvature curves of two pinned-clamped elasticas are firstly efficiently located based on the second-order mode,which are used to determine the shapes of two *** transformations are used to assemble two components together to form the whole elastica,which reveals four kinds of *** advantage of this way compared with other methods such as the shooting method is that multiple coexisting solutions can be located accurately.O n the load-deflection curves,four branches correspond to four kinds of shapes and first two branches are symmetrical to the last two branches relative to the original *** the bilateral displacement control,the critical points can only appear at saddle-node bifurcations,which is different to that for the unilateral displacement ***,one critical point is found on the first branch and two critical points are found on the secondary *** addition,the snap-through among different branches can be well explained with these critical points.

关键词： Elastica Snap-through Critical points Buckling Displacement control

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Impact of coupling geometry on thermoelectric properties of oligophenyl-base transistor

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Chinese Physics B 2017年第2期26卷 420-427页

作者： S Ramezani Akbarabadi h Rahimpour Soleimanit M Bagheri Tagani z Golsanamlou Computational Nanophysics Laboratory （CNL） Department of Physics University of Guilan Rasbt P. O. Box 41335-1914Iran

Thermal and electron transport through organic molecules attached to three-dimensional gold electrodes in two different configurations, namely para and meta with thiol-terminated junctions is studied theoretically in the linear response regime using Green＇s function formalism. We used thiol-terminated（–Sh bond） benzene units and found a positive thermopower because the highest occupied molecular orbital（hOMO） is near the Fermi energy level. We investigated the influence of molecular length and molecular junction geometry on the thermoelectric properties. Our results show that the thermoelectric properties are highly sensitive to the coupling geometry and the molecular length. In addition, we observed that the interference effects and increasing molecular length can increase the thermoelectric efficiency of device in a specific configuration.

关键词： coupling geometry figure of merit Green's function oligophenyl thermopower

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The synthesis of dialdehydes from dicarboxylic acids via imidazolines

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Chinese Science Bulletin 1997年第2期42卷 130-132页

作者： Shi, z Gu, h Xu, LL Department of Chemistry Northwest University Xi’an China

DIALDEhYDES are important chemical industrial materials, which are widely used in textile,medicine, dye, binder, coating and so on. The traditional method for preparing dialdehydes is the catalytic oxidation of glycol. We have reported the reduction ring-opening reaction of inndazoline by NaBh4.In this note, the reduction of imidazoline by sodium and ethanol is studied. A new synthetic method for the preparation of dialdehydes from dicarboxylic acids

关键词： dicarboxylic acid imidazoline dialdehyde new synthetic method.

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Modulators for Terahertz Communication: The Current State of the Art

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Research 2019年第1期2019卷 895-916页

作者： z.T.Ma z.X.Geng z.Y.Fan J.Liu h.D.Chen College of Science Minzu University of ChinaBeijing 100081China School of Information Engineering Minzu University of ChinaBeijing 100081China State Key Laboratory for Integrated Optoelectronics Institute of SemiconductorsChinese Academy of SciencesBeijing 100083China State Key Laboratory of Superlattices and Microstructures Institute of SemiconductorsChinese Academy of SciencesBeijing 100083China

With the increase of communication frequency,terahertz(Thz)communication technology has been an important research feld;particularly the terahertz modulator is becoming one of the core devices in Thz communication *** modulation performance of a Thz communication system depends on the characterization of Thz *** modulators based on diferent principles and materials have been studied and ***,they are still on the way to practical application due to low modulation speed,narrow bandwidth,and insufcient modulation ***,we review the research progress of Thz modulator in recent years and evaluate devices critically and *** focus on the working principles such as electric,optical,optoelectrical,thermal,magnetic,programmable metamaterials and nonlinear modulation methods for Thz wave with semiconductors,metamaterials,and 2D materials(such as graphene,molybdenum disulfde,and tungsten disulfde).Furthermore,we propose a guiding rule to select appropriate materials and modulation methods for specifc applications in Thz communication.

关键词： modulator communication narrow

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Fabrication and Characterization of a 2×2 Microfiber Knot Resonator Coupler

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Chinese Physics Letters 2012年第8期29卷 96-98页

作者： A.A.Jasim A.z.zulkifli M.z.Muhammad h.Ahmad S.W.harun Department of Electrical Engineering University of Malaya 50603 Kuala LumpurMalaysia Photonics Research Center Department of PhysicsUniversity of Malaya50603 Kuala LumpurMalaysia

A 2×2 microfiber knot resonator(MKR)coupler is *** hybrid device is obtained by forming a knot within the coupling region of a microfiber coupler with a 50:50 splitting *** microfiber coupler is successfully fabricated by laterally fusing and tapering two optical fibers using a flame-brushing *** coupler has an overlapping length of 40 mm with a uniform waist of around 5μ*** an MKR structure,the coupler produces a resonant response at both output *** free spectral range of the output spectrum from both ports is obtained at 0.2 nm at a knot diameter of 260μ*** resonance extinction ratio of the device varies from 2 to 6 dB while the calculated Q factor and finesse are~25646 and 3.3,respectively,at both output ports.

关键词： technique fiber resonator

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Tizr-base Bulk Metallic Glass with over 50 mm in Diameter

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Journal of Materials Science & Technology 2010年第6期26卷 481-486页

作者： M. Q. Tang h.F. zhang z. W. zhu h.M. Fu A.M. Wang h. Li z.Q. hu Shenyang National Laboratory for Materials Science Institute of Metal Research Chinese Academy of Sciences 72Wenhua Road Shenyang 110016 China

Low-cost Tizr-base bulk metallic glasses （BMGs）（Ti36.1zr33.2Ni5.8Be24.9）100-xCux （x=5, 7 and g） with a maximum size of over 50 mm in diameter were developed by optimizing the alloy composition. The idea is initiated by selecting a particular microstructure comprising primary β-Ti dendrite and amorphous phase. Afterwards, based on this composition of amorphous phase, a class of Tizr-base bulk metallic glasses was designed step by step to reach the optimum composition range. The glass transition temperature （Tg）, initial crystallization temperature （Tx） and width of supercooled region （AT） of （***33.2Nis.8Be24.9）91Cu9 BMG are 611, 055 and 44 K, respectively. The （Ti36.1zr33.2Ni5.8Be24.9）91Cu9 BMG exhibits low density of 5.541 g·cm-3 and high compressive fracture strength of 1800 MPa, which promises the potential application as structural materials.

关键词： Tizr-base alloy Bulk metallic glass (BMG) Fracture strength

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Mesoporous Carbon-Tin Nanocomposites as Anode Materials for Li-ion Battery

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Journal of Materials Science & Technology 2008年第4期24卷 657-660页

作者： z. W.zhao z.P.Guo P. Yao h.K.Liu Institute for Superconducting and Electronic Materials University of Wollongong NSW 2522 Australia ARC Centre of Excellence for Electromaterials Science University of Wollongong NSW 2522 Australia Centre for Analysis and Measurement Tianjin University Tianjin 300072 China

A new mesoporous carbon-tin （MC-Sn） nanocomposite has been successfully prepared via a two-step method. From the transmission electron microscopy （TEM） observations, the tin nanoparticles were decorated on the as-prepared mesoporous carbons. The mesoprous structure of the carbon can effectively buffer the volume changes during the Li-Sn alloying and de-alloying cycles. The as-prepared MC/Sn nanocomposite electrodes exhibited extremely good cycling stability, with the specific capacity of Sn in the composite electrode calculated to be 959.7 mAh-g-1, which amounts to an impressive 90.9% of the theoretical value （990 mAh-g-1）. The reversible capacity after 200 cycles is 96.1% of the first cycle reversible capacity, i.e., the capacity fade rate is only 0.0195% per cycle, which is even better than that of commercial graphite-based anodes.

关键词： Mesoporous Carbon Tin Nanocomposites Lithium ion battery

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