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Defence Technology（防务技术） 2021年第1期17卷 287-303页

作者： m.Vinyas D.Harursampath S.c.Kattimani Nonlinear multifunctional composites Analysis and Design(NmcAD)Laboratory Department of Aerospace EngineeringIndian Institute of ScienceBangalore560012India Department of mechanical Engineering National Institute of Technology KarnatakaSurathkal575025India

This article deals with evaluating the frequency response of functionally graded carbon nanotube reinforced magneto-electro-elastic(FG-cNTmEE)plates subjected to open and closed electro-magnetic circuit *** this regard finite element formulation has been *** plate kinematics adjudged via higher order shear deformation theory(HSDT)is considered for *** equations of motion are obtained with the help of Hamilton’s principle and solved using condensation *** is found that the convergence and accuracy of the present FE formulation is very good to address the vibration problem of FG-cNTmEE *** the first time,frequency response analysis of FG-cNTmEE plates considering the effect of various circuit conditions associated with parameters such as cNT distributions,volume fraction,skew angle,aspect ratio,length-to-thickness ratio and coupling fields has been carried *** results of this article can serve as benchmark for future development and analysis of smart structures.

关键词： carbon nanotube magneto-electro-elastic Higher order shear deformation theory coupled frequency Electro-magnetic conditions

One and Two Photon Excitation of Radiofrequency Trapped ca

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chinese Journal of chemical Physics 2009年第2期22卷 119-122页

作者： c. Zumsteg c. champenois D. Guyomarc'h G. Hagel m. Houssin m. Knoop Physique des Interactions Ioniques et moléculaires (cNRS UmR 6633) Université de Provence Centre de Saint Jérome Case C21 13397 Marseille Cedex 20 France

Radiofrequency （rf） trapped ions are versatile candidates for a large panel of applications ranging from quantum information to the creation of cold molecules. Sample size can range from a single to 10^6 ions, and the internal and external energy states of the atoms can be controlled with high precision. In the experiment, we focus on different protocols related to frequency metrology using rf trapped ca.

关键词： Radiofrequency trapped ion Frequency metrology Laser stabilisation

Recycled Aggregates:Production,Properties and Value-added Sustainable Applications

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Journal of Wuhan University of Technology(materials Science) 2010年第6期25卷 1011-1016页

作者： LImBAcHIYA m c School of civil Engineering & construction Faculty of EngineeringKingston University-London KT1 2EEUK

Part of an extensive research undertaken by the concrete and masonry Research Group at Kingston University-London was reported to demonstrate through scientific research and full-scale site trials,that quality recycled concrete aggregates can be produced and can be used successfully in a range of concrete *** effects of up to 100% coarse recycled concrete aggregate（RcA） on fresh,engineering and durability related properties were established and assessed its suitability for use in a rage of sustainable applications.

关键词： construction and demolition waste recycling recycled concrete aggregate fresh properties engineering and durability performance

Study on thermal stability of poled non-linear optical polymers

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chinese Journal of chemistry 1996年第5期14卷 472-480页

作者： mhlmann G.R. vanderVorst c.P.J.m. AKZO NOBEL Research Laboratories Arnhem P.O.Box 93006800 SB ArnhemThe NetherlandsAKZO NOBEL Research Laboratories ArnhemP.O.Box 93006800 SB ArnhemThe NetherlandsAKZO NOBEL Research Laboratories ArnhemP.O.Box 93006800 SB ArnhemThe NetherlandsAKZO NOBEL Research Laboratories ArnhemP.O.Box 93006800 SB ArnhemThe Netherlands

A logarithmic expression is proposed to describe relaxation of the polar order in side chain polymers, together with a new way of plotting temperature dependent relaxation data. This results in a straight line extending even below the glass transition temperature in the case of poled nonlinear optics (NLO) side chain polymers. A simple procedure to determine the rotational diffusion constant D-r is given and D-r values of several polymer systems have been evaluated and compared with each other. It appears that, starting from the conventional and well known poled polymer system currently applied, a further lowering of D-r by about 3 orders of magnitude is necessary in order to reach an acceptable orientational stability or lifetime of poled polymers for practical applications. Attempts have been made to introduce electron push-pull substituents into high thermostable molecular frameworks and results of preliminary measurements are reported.

关键词： thermal stability poled polymer film organic nonlinear optical materials

Assessment of cOVID-19 aerosol transmission in a university campus food environment using a numerical method

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Geoscience Frontiers 2022年第6期13卷 265-278页

作者： m.Zhao c.Zhou T.chan c.Tu Y.Liu m.Yu Laboratory of Aerosol Science and Technology China Jiliang UniversityHangzhouChina Department of mechanical Engineering The Hong Kong Polytechnic UniversityKowloonHong KongChina college of modern Science China Jiliang UniversityHangzhouChina

With the prevalence of cOVID-19,the phenomenon of viruses spreading through aerosols has become a focus of *** in university dining halls have a high risk of exposure to respiratory droplets from others without the protection of face masks,which greatly increases the risk of cOVID-19 ***,the transmission mechanism of respiratory droplets in extremely crowded dining environments should be *** this study,a numerical simulation of coughing at dining tables under two conditions was performed,namely the presence and absence of protective partitions,and the evaporation and condensation of aerosol droplets in the air were *** using the numerical method,we analyzed and verified the isolation effect of dining table partitions in the propagation of aerosol *** effect of changes in room temperature on the diffusion of coughed aerosols when partitions were present was *** demonstrated how respiratory droplets spread through coughing and how these droplets affect ***,we proposed a design for a dining table partition that minimizes the transmission of cOVID-19.

关键词： cOVID-19 transmission University dining hall cough Table partition computational fluid dynamics

Diversity and structural composition of species in dipterocarp forests:a study from Fasiakhali Wildlife Sanctuary, Bangladesh

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Journal of Forestry Research 2018年第5期29卷 1241-1249页

作者： S.c.Das m.S.Alam m.A.Hossain Institute of Forestry and Environmental Sciences University of Chittagong

Fasiakhali Wildlife Sanctuary is a protected area composed of tropical remnant rainforest that harbor substantial number of large,old Garjan（Dipterocarpus spp.）*** present study assessed composition,structure and diversity of the species in this protected area.A total of 32 trees species were recorded with DBH ≥ 11 cm belonging to 24 genera and 19 *** forest is low in plant diversity as represented by Shannon–Wiener diversity and Simpson Dominance *** turbinatus was the most dominant species with maximum relative density,frequency,dominance,and importance value *** firmum and Tectona grandis followed in terms of *** structural composition indicated higher number of individuals in the medium growth classes（41 to 〈 511 cm DBH and 16–20 m height ranges）,whereas *** was the only species that dominated most of the growth *** stem density in lower growth classes indicated meager recruitment of regeneration which may be due to lower annual precipitation,increased grazing and *** study will help to understand the patterns of tree species composition and diversity in the remnant dipterocarp forests of *** will also contribute to identifying threatened plants to undertake *** based conservation and sustainable management of the Fasiakhali Wildlife Sanctuary.

关键词： Species diversity Structural composition Protected area Importance value index cluster analysis

STUDY ON cRYOGENIc PHASE cHANGE & WEAR cHARAcTERISTIc OF HIGH SPEED STEEL

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Acta metallurgica Sinica(English Letters) 2003年第6期16卷 524-530页

作者： m.c.Huang c.H.Gao L.G.Huang DepartmentofmechanicalEngineering FuzhouUniversityFuzhou350002China HefeiUniversityofTechnology Hefei230009China

The microscopic structure change rule in high speed steel (HSS) after an additional cryogenic treatment was studied in this paper. Highly dispersed nano-carbide (η-Fe2 c) separated from tempering martensite was found distributed on twin planes of marten-site and dislocation places. Retained austenite was found sheared into martensite and nano-carbide separated at the same time. In addition, the tempering martensite was fine-grained. The stated changes of HSS evidently improve the lifespan of HSS cutter and fully show the advantages of nano-structure. The cryogenic treatment of HSS also improves the roughness of HSS cutter (decrease Ra number by about 50%) and greatly increases the wear resistance of HSS cutter. Further experiments on the wear characteristic of HSS cutter supported the findings mentioned above. The stated HSS treatment technology would implement nano-structure of traditional tool steel through phase change. It could be a new method to improve the performance of HSS cutter.

关键词： high speed steel cryogenic treatment phase change wear char-acteristic nano-structure

Biocompatibility and biotoxicity of in-situ synthesized carboxylated nanodiamond-cobalt oxide nanocomposite

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Journal of materials Science & Technology 2017年第8期33卷 879-888页

作者： L.Syam Sundar Naser A.Anjum m.c.Ferro Eduarda Pereira manoj K.Singh A.c.m.Sousa TEmA-Department of mechanical Engineering University ofAveiroAveiroPortugal cESAm-centrefor Environmental&marine Studies and Department of chemistry University of Aveiro3810-193AveiroPortugal cIcEcO Department of Material Engineering and CeramicsUniversity of AveiroPortugal

A nanocomposite that incorporates cobalt oxide（co3O4） and nanodiamond（ND） can present both high magnetism（co3O4） and high hardness（ND）. ND particles have potential applications in a variety of fields such as protein immobilization, biosensors, therapeutic molecule delivery and bio-imaging. However,limited information is available in literature on the in-situ synthesis of biocompatible magnetic materials and also on their potential biotoxicity as a result of their entry into environmental compartments and subsequent interaction with biota. In this work, a new kind of bio-compatible magnetic material –carboxylated nanodiamond（c ND） and co3O4 was synthesized to obtain the c ND-co3O4 *** synthesis procedure involved in-situ and chemical reduction of cobalt chloride（cocl（26）H2O） and sodium borohydrate（NaBH4）. The synthesized cND-co3O4 nanocomposite was characterized by X-ray diffraction, scanning electron microscopy, transmission electron microscopy and X-ray photoelectron spectroscopy. The cyto-genotoxicity of the synthesized nanocomposite material was studied by using onion（Allium cepa L.） as a test model with concentrations of 5, 10 and 20 μg/ml. The study was also extended to cND and co3O4 materials for comparison purpose. co3O4 and cND exhibited their contrasting effects on mitosis and other cyto-genotoxic indices studied herein. This work provided fundamental data on the synthesis and the bio-toxicity of the c ND-co3O4 nanocomposite, which, in turn, can help to expand their multidisciplinary applications.

关键词： Nanodiamond cobalt oxide Nanodiamond Nanocomposite Bio-toxicity Allium cepa

Turkish bee pollen: composition, regional discrimination and polyphenol bioaccessibility

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FOOD BIOScIENcE 2023年第3期53卷 2702-2710页

作者： mutlu, c. Erbas, m. Akdeniz Univ Engn Fac Food Engn Dept TR-07058 Antalya Turkiye Balikesir Univ Engn Fac Food Engn Dept TR-10145 Balikesir Turkiye

Bee pollen has received significant attention due to its high nutritional value and the phenolic composition responsible for its bioactivity. The current research aims to investigate the phenolic composition and antioxidant capacity of 29 monofloral and 21 polyfloral bee pollen samples obtained from different regions of Turkiye by spectroscopic and chromatographic techniques, making regional discrimination based on identified and quan-tified phenolic compounds and evaluating their bioaccessibility scores by applying a simulated in vitro digestion system. The results demonstrated that the total phenolic and flavonoid contents were 338.15-2857.77 mg GAE/ 100 g and 84.72-544.20 mg QE/100 g, respectively. HPLc-DAD allowed the identification of a total of 20 phenolic compounds, among which rosmarinic acid (155.38 mg/100 g), naringenin (51.91 mg/100 g), and rutin (34.31 mg/100 g) were in higher amounts than the others. Besides phenolic compound findings, linear discriminant analysis findings revealed a significant difference among regions with an accuracy rate of 70%, and the methyl-3,4,5-trihydroxybenzoate was extracted as the most appropriate discriminant variable. moreover, although the amounts of some individual phenolic compounds increased or decreased during digestion, both bioaccessibility and antioxidant activity tended to increase. The mean phenolic bioaccessibility score in the intestinal lumen was recorded as 78.93%. Overall, this study focuses on the phenolic composition in bee pollen and provides substantial information on their antioxidant activity and bioaccessibility degree and highlights the importance of in vivo studies on this issue for a better understanding of the bioaccessibility of bioactive com-pounds in bee pollen.

关键词： Antioxidant Rosmarinic acid Naringenin LDA In vitro digestion

The threshold for a stochastic within-host cHIKV virus model with saturated incidence rate

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International Journal of Biomathematics 2021年第6期14卷 141-172页

作者： c.Gokila m.Sambath Department of mathematics Periyar University Salem 636011India

This paper deals with stochastic chikungunya(cHIKV)virus model along with saturated incidence *** show that there exists a unique global positive solution and also we obtain the conditions for the disease to be *** also discuss about the existence of a unique ergodic stationary distribution of the model,through a suitable Lyapunov *** stationary distribution validates the occurrence of disease;through that,we find the threshold value for prevail and disappear of disease within *** the help of numerical simulations,we validate the stochastic reproduction number Rq as stated in our theoretical findings.

关键词： chikungunya infection model extinction threshold stationary distribution