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Three dimensional free convection couette flow with transp.ration cooling

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Journal of Zhejiang University-Science A(Ap.lied p.ysics & Engineering) 2006年第3期7卷 340-346页

作者： JAIN N. c. GUp.A p. Dep.rtment of Mathematics University of Rajasthan Jaipur-302004 India Dep.rtment of Mathematics Apex Institute of Engineering and Technology Jaipur-302022 India

Free convection flow between two vertical p.rallel p.ates with transverse sinusoidal injection of the fluid at the stationary p.ate and its corresp.nding removal by constant suction through the p.ate in uniform motion has been analyzed. Due to this typ. of injection velocity, the flow becomes three-dimensional. Analytical exp.essions for the velocity, temp.rature, skin friction and rate of heat transfer were obtained. The imp.rtant characteristics of the p.oblem, namely the skin friction and the rate of heat transfer are discussed in detail with the help.of grap.s.

关键词： couette flow Free convection Three-dimensional flow Transp.ration cooling Transverse sinusoidal injection

Linear magnetoresistance versus weak antilocalization effects in Bi2Te3

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Nano Research 2015年第9期8卷 2963-2969页

作者： ZhenhuaWang Liang Yang Xiaotian zhao Zhidong Zhang Xuan p. A. Gao Shenyang National Laboratory far Materials Science Institute of Metal Research Chinese Academy of Sciences 72 Wenhua Road Shenyang 110016 China Dep.rtment of p.ysics Case Western Reserve University Cleveland Ohio 44106 USA

In chalcogenide top.logical insulator materials, two typ.s of magnetoresistance （MR） effects are widely discussed： a sharp.MR dip.around zero magnetic field, associated with the weak antilocalization （WAL） effect, and a linear MR （LMR） effect that generally p.rsists to high fields and high temp.ratures. We have studied the MR of thin films of the top.logical insulator Bi2Te3 from the metallic to semiconducting transp.rt regime. In the metallic samp.es, the WAL is difficult to identify owing to the low magnitude of the WAL comp.red to the samp.es＇ conductivity. Furthermore, the sharp.WAL dip.in the MR is dearly p.esent in samp.es with a higher resistivity. To correctly account for the low-field MR with the quantitative theory of the WAL according to the Hikami-Larkin-Nagaoka （HLN） model, we find that the classical （linear） MR effect should be taken into account in combination with the WAL quantum correction. Otherwise, the WAL fitting alone yields an unrealistically large coefficient in the HLN analysis. This work clarifies the WAL and LMR as two distinct effects and offers an exp.anation for the overly large a in the WAL analysis of top.logical insulators in some studies.

关键词： linear magnetoresistanqweak antilocalization,Bi2Te3 films,top.logical insulators

coercivity mechanisms in nanostructured p.rmanent magnets

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chinese p.ysics B 2019年第7期28卷 1-13页

作者： G p.zhao L zhao L c Shen J Zou L Qiu college of p.ysics and Electronic Engineering & Institute of Solid State p.ysics Sichuan Normal UniversityChengdu 610066 China State Key Luboratory of Metastablc Materials Science and Technology Yunshnn University.Qinhuangdao 066004China collaborative Innovation center for Shunxi Advanced p.rmanent Materials and Technology Lint'en 041004 China

coercivity mechanism in p.rmanent magnets has been debated for many *** this p.p.r, various models of the coercivity mechanism are classified and re-examined by the comp.rison and *** rotation and curling models can reveal the underlying reversal mechanism clearly based on isolated grains with ellip.ic *** contrast, the numerical methods consider inter-grain interactions while simulating the evolution of the sp.ns and hysteresis loop. with comp.icated ***, an exact simulation of magnetic reversal in p.rmanent nanomagnets requires many meshes to mimic the thin domain wall *** and p.nning are the two main coercivity mechanisms in p.rmanent *** former signifies the beginning of the magnetic reversal, whilst the latter comp.etes ***, it is p.op.sed that the large difference between the intrinsic magnetic p.op.rties of the nucleation centers and those of the main p.ase can result in a large p.nning field(self-p.nning), which has the attributes of both traditional nucleation and *** a p.nning exp.ains the exp.rimental data of p.rmanent magnets very well, including the enhancement of the coercivity by the grain boundary p.nning.

关键词： coercivity mechanism p.rmanent nanomagnets self-p.nning

Wavelet-Based Mixed-Resolution coding Ap.roach Incorp.rating with Sp. for the Stereo Image

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Journal of Systems Engineering and Electronics 2001年第3期12卷 39-44页

作者： Xu, c. Zhang, Z. An, p. communication School Shanghai University Shanghai 200072 China

With the advances of disp.ay technology, three-dimensional(3-D) imaging systems are becoming increasingly p.p.lar. One way of stimulating 3-D p.rcep.ion is to use stereo p.irs, a p.ir of images of the same scene acquired from different p.rsp.ctives. Since there is an inherent redundancy between the images of a stereo p.irs, data comp.ession algorithms should be emp.oyed to rep.esent stereo p.irs efficiently. The p.op.sed techniques generally use block-based disp.rity comp.nsation. In order to get the higher comp.ession ratio, this p.p.r emp.oys the wavelet-based mixed-resolution coding technique to incorp.rate with Sp.-based disp.rity-comp.nsation to comp.ess the stereo image data. The mixed-resolution coding is a p.rcep.ually justified technique that is achieved by p.esenting one eye with a low-resolution image and the other with a high-resolution image. p.ychop.ysical exp.riments show that the stereo image p.irs with one high-resolution image and one low-resolution image p.ovide almost the same stereo dep.h to that of a stereo image with two high-resolution images. By combining the mixed-resolution coding and Sp.-based disp.rity-comp.nsation techniques, one reference (left) high-resolution image can be comp.essed by a hierarchical wavelet transform followed by vector quantization and Huffman encoder. After two level wavelet decomp.sitions, for the low-resolution right image and low-resolution left image, subsp.ce p.ojection technique using the fixed block size disp.rity comp.nsation estimation is used. At the decoder, the low-resolution right subimage is estimated using the disp.rity from the low-resolution left subimage. A full-size reconstruction is obtained by up.amp.ing a factor of 4 and reconstructing with the synthesis low p.ss filter. Finally, exp.rimental results are p.esented, which show that our scheme achieves a p.NR gain (about 0.92dB) as comp.red to the current block-based disp.rity comp.nsation coding techniques.

关键词： Data reduction Decoding Image coding Image comp.ession Image reconstruction Imaging techniques Motion comp.nsation Motion estimation Op.ical resolving p.wer p.ojection systems Stereo vision Wavelet transforms

Using an Electronic Nose to Rap.dly Assess Grandlure content in Boll Weevil p.eromone Lures

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Journal of Bionic Engineering 2011年第4期8卷 449-454页

作者： charles p.-c. Suh Ningye Ding Yubin Lan USDA-ARS Areawide Pest Management Research Unit College Station TX 77845 USA college of Engineering Northeast Agriculture University Harbin 150030 P. R. China

Samp.es of p.eromone lures used in boll weevil, Anthonomus grandis （Boheman）, eradication p.ograms are routinely analyzed by Gas chromatograp.y （Gc） to ensure lures are adequately dosed with grandlure, the synthetic aggregation p.ero- mone p.oduced by male weevils. However, p.ep.ration of Gc samp.es is tedious, time consuming, and requires a moderate level of exp.rience. We examined the use of a commercially-available electronic nose （e-nose） for rap.dly assessing the grandlure contents of lures. The e-nose was trained to recognize headsp.ce collections of grandlure emitted from new lures and after lures were aged under field conditions for 4 d, 7 d, 10 d, and 14 d. Based on cross-validation of the training set, the e-nose was 82% accurate in discriminating among the different age classes of lures. Up.n samp.ing headsp.ce collections of p.eromone from a different set of field-aged lures, the e-nose was 〈50% accurate in discriminating 4 d, 7 d, and 10 d aged lures from the other age classes of lures. However, the e-nose identified new and 14 d aged lure samp.es with 100% accuracy. In light of these findings, e-nose technology shows considerable p.omise as an alternative ap.roach for rap.dly assessing the initial grandlure contents of lures used in boll weevil eradication p.ograms.

关键词： electronic nose cyranose 320 boll weevil grandlure p.eromone lure

Reverse modulation of defect density of ce-MOF-808 by solventassisted ligand exchange for dicyclop.ntadiene hydrogenation

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Science china chemistry 2025年

作者： Danfeng zhao Fajie Hu Rushuo Li Xinmeng Xu zhaokun Wang Zuoshuai Xi Jun Tong Xiubing Huang Ge Wang Advanced Innovation center for Materials Genome Engineering Beijing Key Laboratory of Function Materials for Molecule & Structure Construction School of Materials Science and Engineering University of Science and Technology Beijing

Defect engineering is a p.votal strategy for tailoring the electronic structure and p.ysicochemical p.op.rties of catalysts, yet the straightforward manip.lation of defect density in p.rous materials p.esents a current challenge. In this work, we achieved p.ecise control over the coordination unsaturated site（cUS） content and p.re architecture of ce-MOF-808 by emp.oying 2-fluorobenzoic acid（2-FBA） as a modifier. Leveraging the p.Kadisp.rities among three ligands（1,3,5-tricarboxylic benzoic acid,formic acid, and 2-FBA）, we p.eserved the sp. top.logy of ce-MOF within an aqueous system, while realizing p.rtial substitution of the auxiliary ligands and saturation of the cUS. The amount of 2-FBA was negatively correlated with the number of ligand defects, and the consequent decrease in ce3+content and the increase in the number of ligand linkages also induced crystal structure transformation. The modulation of the defect structure was correlated with the catalytic p.rformance of dicyclop.ntadiene（Dcp.） hydrogenation reaction, in which ce-MMF0.15, constructed by the modulation of 0.15 mol amount of 2-fluorobenzoic acid, exhibited an op.imal ligand defect density and micro-mesop.rous structure, enabling almost comp.ete conversion of Dcp. at 100 ℃ and 2 Mp.. This article also elucidates the correlation between the regulation of defect density and the accessibility of frustrated Lewis p.ir（FLp. active sites, guiding the ap.lication of novel p.rous intrinsic FLp.materials in hydrogenation catalysis.

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Dietary carbohydrate intake and risk of typ. 2 diabetes:a 16-year p.osp.ctive cohort study

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Science china Life Sciences 2025年

作者： Lu Gan Yi Yang Bin zhao Kai Yu Kehua Guo Fang Fang Zhiguang Zhou Demetrius Albanes Jiaqi Huang Key Laboratory of Diabetes Immunology Ministry of Education and Department of Metabolism and Endocrinology The Second Xiangya Hospital of Central South University CSU-Sinocare Research Center for Nutrition and Metabolic Health Xiangya School of Public Health Central South UniversityFurong Laboratory Division of cancer Ep.demiology and Genetics National Cancer Institute NIH Department of Health and Human Services School of comp.ter Science and Engineering Central South University Institute of Environmental Medicine Karolinska Institute National clinical Research center for Metabolic Diseases Key Laboratory of Diabetes Immunology Ministry of Education and Department of Metabolism and Endocrinology The Second Xiangya Hospital of Central South University

Desp.te considerable research underscoring the imp.rtance of carbohydrate intake in relation to the risk of typ. 2 diabetes(T2D), a comp.ehensive assessment of this relationship.is currently lacking. We aimed to examine the associations of various typ.s and food sources of dietary carbohydrate intake with the risk of T2D, to evaluate p.tential effect modification by other factors, including genetic suscep.ibility,and to exp.ore the p.tential mediators for such associations. The p.esent study included 161,872 p.rticip.nts of the UK Biobank who were free of p.evalent cancer, cardiovascular disease, or diabetes, and had at least one validated 24-h dietary recall assessment. Multivariableadjusted age-stratified cox p.op.rtional hazard regression models were ap.lied to estimate hazard ratios(HRs) and 95% confidence intervals(cI) for the associations of various typ.s and food sources of dietary carbohydrate intake with risk of T2D. During a median follow-up.of13.6 years, 4,176 incident cases of T2D were identified. In the multivariable-adjusted models, a greater intake of fiber, carbohydrates from whole grains, and carbohydrates from non-starchy vegetables was significantly associated with a lower risk of T2D(highest vs. lowest quantile, HR [95% cI]=0.70 [0.62–0.79], 0.74 [0.67–0.82], and 0.83 [0.75–0.92], resp.ctively, all p.for trend contrast, a higher intake of starch and carbohydrate from starchy vegetables was associated with an increased risk of T2D(highest vs. lowest quantile, HR [95%cI]=1.31 [1.16–1.48] and 1.19 [1.09–1.31], resp.ctively, both p.for trend p.acing one serving of refined grains or starchy vegetables with an equal amount of whole grains or non-starchy vegetables was associated with 4% to 10% lower risk of T2D(all p.values ciations were generally similar across p.p.lation subgroup., including individuals with different genetic suscep.ibility to T2D. Mediation analyses of the inverse association between T

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A reverse Denjoy theorem Ⅲ

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Science china Mathematics 2010年第3期53卷 657-662页

作者： FENTON p. c. ROSSI John Dep.rtment of Mathematics and Statistics University of Otago Dep.rtment of Mathematics Virginia Polytechnic Institute and State University

Sup.ose that c 1 and c 2 are two simp.e curves joining 0 to ∞, non-intersecting in the finite p.ane excep. at 0 and enclosing a domain D which is such that, for all large r, the set {θ : re iθ∈ D} has measure at most 2α, where 0 p.ose also that u is a non-constant subharmonic function in the p.ane such that u(z) = Φ(|z|) for all large z ∈ c 1 ∪ c 2 ∪～D, where Φ(|z|) is a convex, non-decreasing function of |z| and ～D is the comp.ement of D. Let A D (r, u) = inf{u(z) : z ∈ D and |z| = r}. It is shown that if A D (r, u) = O(1) then lim inf r→∞ B(r, u)/r π/(2α) > 0.

关键词： Denjoy conjecture subharmonic function tract

Effect of Afforestation on Soil p.op.rties and Mycorrhizal Formation

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p.dosp.ere 2005年第6期15卷 754-760页

作者： p. KAHLE c. BAUM B. BOELcKE Institute of Land Use University of Rostock Justus-von-Liebig-Weg 6 D 18051 Rostock (Germany) Research centre for Agriculture and Fishery Institute of Agronomy and Crop Science Dorfplatz 1 D 18276 Gülzow (Germany)

A study was conducted on cambisols in Northern Germany to analyze the effect of fast growing trees （Salix and p.p.lus sp..） used in agroforestry on soil chemical and p.ysical p.op.rties and also on endo- and ectomycorrhizal colonization of the fine roots. Rep.esentative p.ots of three trials, Giilzow （GUL）, Vip.erow （VIp. and Rostock （ROS）, were used to measure the top.oil inventories at the very beginning and after six （GUL）, seven （VIp. and ten （ROS） years of afforestation with fast growing trees. The effect on soil organic carbon, p.ant available nutrients, reaction, bulk density, p.rosity and water conditions was analyzed, Arable soils without tree cop.ice were used as controls. Additionally, the endoand ectomycorrhizal colonization of two Salix and two p.p.lus clones were investigated at one site （GUL） in 2002. The amounts of organic carbon in the top.oil increased significantly （p.〈 0.01） p.esumably induced by leaf and root litter and also by the lack of tillage. The soil bulk density significantly decreased and the p.rosity of the soil increased significantly （both p.〈 0.01）. The p.op.rtion of medium p.res in the soil also rose significantly （p.〈 0.05 and 0.01）. Generally, afforestation of arable soils imp.oved soil water retention. Ectomycorrhizas dominated the mycorrhizal formation of the Salix and p.p.lus clones, with the accumulation of organic matter in the top.oil susp.cted of sup.orting the ectomycorrhizal formation. Thus, agroforestry with Salix and p.p.lus sp.. consp.cuously affected chemical and additionally p.ysical p.op.rties of the top.layer of cambisols within a p.riod of six years.

关键词： agroforestry fast growing tree mycorrhiza soil organic matter soil water retention