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transport mechanism in chemically reactive hybrid nanofluid flow containing gyrotactic micro-organisms over a curved oscillatory surface

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Applied Mathematics and Mechanics(English Edition) 2025年第1期46卷 177-192页

作者： M.NAVEED M.IMRAN t.ASGHAR Z.ABBAS Department of Mathematics Division of Science and TechnologyUniversity of Education Department of Mathematics The Islamia University of Bahawalpur

this paper examines the transport analysis, including both heat transfer and mass transfer, in hybrid nanofluid flow containing gyrotactic microorganisms towards a curved oscillatory surface. the influence of magnetic fields is also inspected in terms of their physical characteristics. to depict the phenomena of transport, modified versions of both Fick's and Fourier's laws are used. Additionally, the characteristics of both heterogeneous and homogeneous chemical reactions are also incorporated. Utilizing a curvilinear coordinate system, the flow problem is formulated as partial differential equations(PDEs)for momentum, concentration, microorganism field, and energy. An analytical solution to the obtained flow equations is achieved utilizing the homotopy analysis method(HAM).the effects of significant flow parameters on the pressure and microorganism fields, velocity, oscillation velocity, concentration, and temperature distributions are shown via graphs. Furthermore, the variations in skin friction, mass transfer rate, heat transfer rate, and local motile number due to different involved parameters are presented in tables and are analyzed in detail. Graphical results indicate that the curves of velocity and temperature fields are enhanced as the values of the solid volume fraction variables *** is also verified that the concentration rate field decreases as the values of the homogeneous reaction strength parameter and the radius of curvature parameter increase, and it increases with the Schmidt number and the heterogeneous reaction strength *** outcomes show a favorable response of the motile number to advanced values of the Peclet number, the Schmidt number, the microorganism difference parameter, and the bio-convective Lewis number.

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Silencing Brassinosteroid Receptor BRI1 Impairs Herbivory-elicited Accumulation of Jasmonic Acid-isoleucine and Diterpene Glycosides, but not Jasmonic Acid and trypsin Proteinase Inhibitors in Nicotiana attenuata

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Journal of Integrative Plant Biology 2013年第6期55卷 514-526页

作者： da-Hai Yang Ian t. Baldwin Jianqiang Wu Department of Molecular Ecology Max Planck Institute for Chemical Ecology Hans-Knll Stra e 8 D-07745 Jena Germany Plant Stress Biology Group Shanghai Center for Plant Stress Biology Shanghai Institutes for Biological Sciences the Chinese Academy of Sciences Key Laboratory of Economic Plants and Biotechnology Kunming Institute of Botany the Chinese Academy of Sciences

the brassinosteroid （BR） receptor, BR insensitive 1 （BRI1）, plays a critical role in plant development, but whether BRI1-mediated BR signaling is involved in plant defense responses to herbivores was largely unknown. Here, we examined the function of BRI1 in the resistance of Nicotiana attenuata （Solanaceae） to its specialist insect herbivore Manduca sexta. Jasmonic acid （JA） and JA-isoleucine conjugate （JA-Ile） are important hormones that mediate resistance to herbivores and we found that after wounding or simulated herbivory NaBRI1 had little effect on JA levels, but was important for the induction of JA-Ile. Further experiments revealed that decreased JAR （the enzyme for JA-Ile production） activity and availability of Ile in NaBRI1-silenced plants were likely responsible for the low JA-Ile levels. Consistently, M. sexta larvae gained more weight on NaBRI1-silenced plants than on the control plants. Quantification of insect feeding-induced secondary metabolites revealed that silencing NaBRI1 resulted in decreased levels of carbon-rich defensive secondary metabolites （hydroxygeranyllinalool diterpene glycosides, chlorogenic acid, and rutin）, but had little effect on the nitrogen-rich ones （nicotine and trypsin proteinase inhibitors）. thus, NaBRI1-mediated BR signaling is likely involved in plant defense responses to M. sexta, including maintaining JA-Ile levels and the accumulation of several carbon-rich defensive secondary metabolites.

关键词： BRI1 herbivore insect jasmonic acid Nicotiana attenuata secondary metabolites.

An analytical approach to reconstruction of axisymmetric defects in pipelines using t(0,1)guided waves

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Applied Mathematics and Mechanics(English Edition) 2020年第10期41卷 1479-1492页

作者： Yihui da Bin WANG D.Z.LIU Zhenghua QIAN State Key Laboratory of Mechanics and Control of Mechanical Structures College of Aerospace EngineeringNanjing University of Aeronautics and AstronauticsNanjing 210016China School of Engineering University of East AngliaNorwich NR47TJU.K

torsional guided waves have been widely utilized to inspect the surface corrosion in pipelines due to their simple displacement behaviors and the ability of longrange ***,the torsional mode t(0,1),which is the first order of torsional guided waves,plays the irreplaceable position and role,mainly because of its non-dispersion characteristic ***,one of the most pressing challenges faced in modern quality inspection is to detect the surface defects in pipelines with a high level of *** into account this situation,a quantitative reconstruction method using the torsional guided wave t(0,1)is proposed in this *** methodology for defect reconstruction consists of three ***,the reflection coefficients of the guided wave t(0,1)scattered by different sizes of axisymmetric defects are calculated using the developed hybrid finite element method(HFEM).then,applying the boundary integral equation(BIE)and Born approximation,the Fourier transform of the surface defect profile can be analytically derived as the correlative product of reflection coefficients of the torsional guided wave t(0,1)and the fundamental solution of the intact pipeline in the frequency ***,reconstruction of defects is precisely performed by the inverse Fourier transform of the product in the frequency *** experiments show that the proposed approach is suitable for the detection of surface defects with arbitrary ***,the effects of the depth and width of surface defects on the accuracy of defect reconstruction are *** is noted that the reconstructive error is less than 10%,providing that the defect depth is no more than one half of the pipe thickness.

关键词： torsional guided wave hybrid finite element method(HFEM) boundary integral equation(BIE) quantitative reconstruction

Guarding tomato fruit setting in adverse temperatures through the miRNA166-S/HBt5A regulatory module

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Molecular Plant 2021年第7期14卷 1046-1048页

作者： Eder M.da Silva Fabio t.S.Nogueira Centro de Energia Nuclear na Agricultura Universidade de Sao Paulo/USPPiracicabaSP 13400-970Brazil Laborat6rio de Genetica Molecular do Desenvolvimento Vegetal Departamento de Ciencias BiologicasESALQ/USPPiracicabaSP 13418-900Brazil

Fruits are defined as mature ovaries originated from a coordinated development between ovules(precursors of seeds)and carpels(precursors of the fruit body).Disconnecting the ovule development from carpel development is a long-desired goal in agriculture to generate seedless fruits easier to ***,pollination and fertilization are required to promote hormone pathways-i.e.,auxin and gibberellin-that are crucial for seed and fruit set(Gillaspy et al.,1993;Raghavan,2003).Even though developing seeds are central for normal fruit development,examples of seedless or parthenocarpic fruits are present in wild and cultivated species(Joldersma and Liu,2017).

关键词： Guard connecting originated

Synthesis, Resolution, and Enantiomeric Purity Assay of 2-n-Butylbutanedioic Acid 4-t-Butyl Esters

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Chemical Research in Chinese Universities 2006年第5期22卷 584-588页

作者： ZHANG da-tong tANG Li-da DUAN Gui-yun ZHAO Gui-long XU Wei-ren MENG Li-juan WANG Jian-wu School of Chemistry and Chemical Engineering Shandong University Jinan 250100 P. R. China the Pharmaceutical Research Institute of tianjin Tianjin 300193 P. R. China

Racemic 2-n-butylbutanedioic acid 4-t-butyl esters were synthesized from methyl hexanoate and t-butyl α-iodoacetate via alkylation and subsequently selective hydrolyzation. the （R）-and （S）-2-n-butylbutanedioic acid 4-t-butyl esters were obtained by the resolution of the above-mentioned racemic compounds with（S）-（ - ） or（R）-（＋）-α- methylbenzylamine, respectively. the e.e. values of the two optical active products were determined to be above 99% by HPLC after the formation of two pairs of diastereoisomers with（R）-（＋）-α-methylbenzylamine and（S）- phenylalanine methyl ester.

关键词： Methyl hexanoate 4-t-Butyl 2-n-butylbutanedioic acid Resolution e.e. Value

transient behaviors of a flame over a tsuji burner

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Acta Mechanica Sinica 2008年第6期24卷 645-659页

作者： Young-da Chen da-da Chen Chiun-Hsun Chen Department of Mechanical Engineering National Chiao Tung UniversityHsinChu 30056TaiwanChina

the present study investigated numerically the physical mechanisms underlying the transient behaviors of the flame over a porous cylindrical burner. the numerical results showed that a cold flow structure at a fixed inflow velocity of Uin = 0.6 m/s in a wind tunnel could be observed in two co-existing recirculation flows. Flow variations occur repeatedly until t = 4.71 s, and then a vortex existed steadily behind the burner and no shading occurred. the ignition of flammable mixture led to a rapid rise in gas temperature and a sudden gas expansion. When it reached the stable envelope flame condition, Uin is adjusted to an assigned value. two blow-off mechanisms were identified. It was also found in the study flame shapes with buoyancy effects agreed with the ones observed experimentally by tsai. Furthermore, the lift-off flame would appear briefly between the envelopes and wake ones, and was stabilized as a wake flame.

关键词： tsuji burner Lift-off flame Recirculation flow

Corrosion behavior of the friction-stir-welded joints of 2A14-t6 aluminum alloy

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International Journal of Minerals,Metallurgy and Materials 2015年第6期22卷 627-638页

作者： Hai-long Qin Hua Zhang da-tong Sun Qian-yu Zhuang School of Materials Science and Engineering University of Science and Technology Beijing the Welding Institute Chongqing Changan Automobile Co. Ltd.

the corrosion behavior of friction-stir-welded 2A14-t6 aluminum alloy was investigated by immersion testing in immersion exfoliation corrosion（EXCO） solution. Electrochemical measurements（open circuit potential, potentiodynamic polarization curves, and electrochemical impedance spectroscopy）, scanning electron microscopy, and energy dispersive spectroscopy were employed for analyzing the corrosion mechanism. the results show that, compared to the base material, the corrosion resistance of the friction-stir welds is greatly improved, and the weld nugget has the highest corrosion resistance. the pitting susceptibility originates from the edge of Al-Cu-Fe-Mn-Si phase particles as the cathode compared to the matrix due to their high self-corrosion potential. No corrosion activity is observed around the θ phase（Al2Cu） after 2 h of immersion in EXCO solution.

关键词： aluminum alloys friction stir welding joints corrosion in-situ observation

Decoding the evolution and transmissions of the novel pneumonia coronavirus(SARS-CoV-2/HCoV-19)using whole genomic data

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Zoological Research 2020年第3期41卷 247-257页

作者： Wen-Bin Yu Guang-da tang Li Zhang Richard t.Corlett Center for Integrative Conservation Xishuangbanna Tropical Botanical GardenChinese Academy of SciencesMenglaYunnan 666303China Center of Conservation Biology Core Botanical GardensChinese Academy of SciencesMenglaYunnan 666303China Henry Fok College of Biology and Agriculture Shaoguan UniversityShaoguanGuangdong 512005China College of Forestry and Landscape Architecture South China Agricultural UniversityGuangzhouGuangdong 510642China Chinese Institute for Brain Research Beijing 102206China

the outbreak of COVID-19 started in mid-December2019 in Wuhan, China. Up to 29 February 2020,SARS-CoV-2(HCoV-19/2019-nCoV) had infected more than 85 000 people in the world. In this study,we used 93 complete genomes of SARS-CoV-2 from the GISAID EpiFlu tM database to investigate the evolution and human-to-human transmissions of SARS-CoV-2 in the first two months of the *** constructed haplotypes of the SARS-CoV-2 genomes, performed phylogenomic analyses and estimated the potential population size changes of the virus. the date of population expansion was calculated based on the expansion parameter tau(τ)using the formula t=τ/2 u. A total of 120 substitution sites with 119 codons, including 79 non-synonymous and 40 synonymous substitutions, were found in eight coding-regions in the SARS-CoV-2 *** non-synonymous substitutions are potentially associated with virus adaptation. No combinations were detected. the 58 haplotypes(31 found in samples from China and 31 from outside China)were identified in 93 viral genomes under study and could be classified into five groups. By applying the reported bat coronavirus genome(bat-RatG13-CoV)as the outgroup, we found that haplotypes H13 and H38 might be considered as ancestral haplotypes,and later H1 was derived from the intermediate haplotype H3. the population size of the SARS-CoV-2 was estimated to have undergone a recent expansion on 06 January 2020, and an early expansion on 08 December 2019. Furthermore,phyloepidemiologic approaches have recovered specific directions of human-to-human transmissions and the potential sources for international infected cases.

关键词： COVID-19 HCoV-19 SARS-CoV-2 Novel pneumonia outbreak Human-to-human transmission Phyloepidemiology

Effects of postweld aging on the microstructure and properties of bobbin tool friction stir-welded 6082-t6 aluminum alloy

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International Journal of Minerals,Metallurgy and Materials 2019年第7期26卷 849-857页

作者： Yu-peng Li da-qian Sun Wen-biao Gong Liang Liu Key Laboratory of Automobile Materials Ministry of Education Jilin University Changchun 130025 China School of Materials Science and Engineering Jilin University Changchun 130025 China Key Laboratory of Advanced Structural Materials Ministry of Education Changchun University of Technology Changchun 130012 China School of Materials Science and Engineering Changchun University of Technology Changchun 130012 China

Samples of 6082-t6 aluminum alloy were subjected to bobbin tool friction stir welding (Bt-FSW), and the joints were treated by postweld natural aging (PWNA) and postweld artificial aging (PWAA). the microstructure, microhardness, and tensile properties of the aged and as-welded specimens were investigated. transmission electron microscopy (tEM) observations revealed that a large number of Guinier–Preston (GP) zones precipitated in the form of a network on the stir zone (SZ) after PWNA for 60 d, and a large number of β'' phases precipitated in the matrix for after PWAA for 6 h. As the aging time increased, the microhardness of the SZ and the thermomechanically affected zone (tMAZ) increased significantly, and the hardness of the SZ after PWAA for 6 h was close to that of the base metal (BM). With increasing PWNA time, the strength and strain increased slightly. When the PWAA time increased, the strength clearly increased, with a maximum value of 279.9 MPa after 6 h, while the strain decreased.

关键词： postweld aging aluminum alloys bobbin tool friction stir welding microstructure properties