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The Tertiary Volcanic Rocks of Fangshan,chiangning,Kiangsu

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地质学报 1948年第Z2期 4+108-162页

作者： Y.c.chENG and Y.h.ShEN (Geological Survey of china)

关键词： der The Tertiary Volcanic Rocks of Fangshan,chiangning,Kiangsu

Deformation heterogeneity of Ti under cryogenic channel-die compression

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Progress in Natural Science:Materials International 2011年第4期21卷 277-285页

作者： K.h.KIM S.K.hWANG Division of Materials Science and Engineering Inha University

commercial purity Ti was subjected to channel die compression in liquid nitrogen for the purpose of studying its deformation characteristics from the viewpoint of the grain refinement induced by severe plastic *** specimens showed microstructural heterogeneity in that the initial blocky grains of about 50 urn in size turned into a mixture of the easily deforming soft grains and the hard grains revealing local concentration of dislocations and deformation *** electron back scattered diffraction analysis the in-grain misorientation-axis distribution was studied,from which it was found that the deformation heterogeneity resulted from the anisotropy of individual grains with respect to the compression die:while the soft grains were those oriented favorably for the prismslip,the hard ones were oriented for non-prism slips and deformation *** difference in the response of individual grains,therefore,led to a remarkable effect of the crystal texture of specimens on the maximum strain that can be imposed on specimens without *** on the present results,a way to achieve expedient grain refinement through the cryogenic plane-strain compression was suggested.

关键词： titanium cryogenic deformation texture microstructure

cranial differences in three-toed jerboas(Dipodinae,Dipodidae,Rodentia)according to recent taxonomic revisions

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current Zoology 2023年第4期69卷 475-490页

作者： Bader h.Alhajeri Zahraa hasan hasan Alhaddad Department of Biological Sciences Kuwait UniversitySafat13060Kuwait

Recent phylogenetic studies amended the taxonomy of three-toed jerboas(subfamily Dipodinae),including raising subspecies to full ***,we use geometric morphometrics to compare scaled-shape differences in dipodine crania while considering their revised *** sampled Dipus deasyi,*** halli,***,Jaculus blanfordi blanfordi,***,***,***,*** gerboa,***,and Stylodipus *** were not sexually *** allometry explained some of the shape variation,for example,reduced braincases in larger *** operational taxonomic unit pairs differed in both size and *** and Stylodipus clustered together based on their cranial *** differed from the aforementioned genera by its larger tympanic bulla,broader braincase,larger infraorbital foramen,along with reduced molars and *** orientalis differed from other Jaculus by its broader face versus reduced cranial *** blanfordi(subgenus haltomys)resembles members of the subgenus Jaculus more than its consubgener(***).Jaculus loftusi,previously considered a synonym of ***,clearly differed from the latter by its shorter rostrum,smaller infraorbital foramen,and more caudolaterally expanded tympanic *** hirtipes,another recent synonym of ***,resembled *** more in scaled cranial shape than it did *** sagitta halli and *** were indistinguishable,but they clearly differed from ***(recently raised to full species)with the latter having a larger molar row,more inflated tympanic bulla,and shorter,slenderer *** explanations for detected cranial shape differences are considered,including diet and habitat(particularly substrate).

关键词： crania Dipus deasyi Jaculus hirtipes Jaculus loftusi jerboa Stylodipus andrewsi

Discriminative graph regularized broad learning system for image recognition

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Science china(Information Sciences) 2018年第11期61卷 179-192页

作者： Junwei JIN Zhulin LIU c.L.Philip chEN Faculty of Science and Technology University of Macau Dalian Maritime University State Key Laboratory of Management and control for complex Systems Institute of AutomationChinese Academy of Sciences

Broad learning system(BLS) has been proposed as an alternative method of deep learning. The architecture of BLS is that the input is randomly mapped into series of feature spaces which form the feature nodes, and the output of the feature nodes are expanded broadly to form the enhancement nodes, and then the output weights of the network can be determined analytically. The most advantage of BLS is that it can be learned incrementally without a retraining process when there comes new input data or neural nodes. It has been proven that BLS can overcome the inadequacies caused by training a large number of parameters in gradient-based deep learning algorithms. In this paper, a novel variant graph regularized broad learning system(GBLS) is proposed. Taking account of the locally invariant property of data, which means the similar images may share similar properties, the manifold learning is incorporated into the objective function of the standard BLS. In GBLS, the output weights are constrained to learn more discriminative information,and the classification ability can be further enhanced. Several experiments are carried out to verify that our proposed GBLS model can outperform the standard BLS. What is more, the GBLS also performs better compared with other state-of-the-art image recognition methods in several image databases.

关键词： broad learning system deep learning graph regularization image recognition feature extraction incremental learning

Design and fabrication of automated sedimentation-based separation and siphon-based extraction for detection of allergic reaction on a centrifugal microfluidic disc

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chinese Optics Letters 2010年第10期8卷 957-959页

作者： Q. L. chen h. P. ho K. L. cheung S. K. Kong Y. K. Suen Y. W. Kwan c. K. Wong center for Advanced Research in Photonics and Department of Electronic Engineering The Chinese University of Hong Kong Hong Kong China Department of Biochemistry The Chinese University of Hong Kong Hong Kong China School of Biomedical Sciences The Chinese University of Hong Kong Hong Kong China Department of chemical Pathology The Chinese University of Hong Kong Hong Kong China

We report the design and fabrication of a novel and fully integrated polymer-based centrifugal microfluidic disc for rapid automatic allergens detection. All essential steps for a single test including flow valving, sequencing, mixing, separation, extraction, and sedimentation for final detection are automatically conducted within 30 min on a centrifugal microfluidic disc. Our design features a siphon-based valving and analyte extraction structure where the released analyte is separated and subsequently extracted by a siphon valve into the detection chamber. Incorporating the siphon valve and a series of capillary valves, we realize automated detection of allergic reaction on a centrifugal microfluidic disc.

关键词： Adaptive optics Diffuse optical imaging Photolithography Polydimethylsiloxane Polymethyl methacrylate

Ferromagnetism and ferroelectricity in a superlattice of antiferromagnetic perovskite oxides without ferroelectric polarization

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npj computational Materials 2023年第1期9卷 632-637页

作者： Paresh c.Rout Avijeet Ray Udo Schwingenschlögl Physical Sciences and Engineering Division(PSE) King Abdullah University of Science and Technology(KAUST)Thuwal 23955-6900Saudi Arabia

We study the structural,electronic,and magnetic properties of the SrcrO_(3)/YcrO_(3) superlattice and their dependence on epitaxial *** discover that the superlattice adopts A-type antiferromagnetic(A-AFM)ordering in contrast to its constituents(SrcrO_(3):c-AFM;YcrO_(3):G-AFM)and retains it under compressive strain while becoming ferromagnetic(5μB per formula unit)at+1%*** obtained ferroelectric polarization is significantly higher than that of the R2NiMnO6/La2NiMnO6(R=ce to Er)series of superlattices[***.5,4021(2014)]due to a large difference between the antipolar displacements of the Sr and Y *** superlattice is a hybrid-improper multiferroic material with a spontaneous ferroelectric polarization(13.5μc/cm^(2))approaching that of bulk BaTiO_(3)(19μc/cm^(2)).The combination of ferromagnetism with ferroelectricity enables multistate memory *** addition,the charge-order-driven p-type semiconducting state of the ferromagnetic phase(despite the metallic nature of SrcrO_(3))is a rare property and interesting for *** carlo simulations demonstrate a magnetic critical temperature of 90 K for the A-AFM phase without strain and of 115 K for the ferromagnetic phase at+5%strain,for example.

关键词： ferroelectric superlattice ferromagnetic

cryogenic nanosecond and picosecond high average and peak power(hAPP) pump lasers for ultrafast applications

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high Power Laser Science and Engineering 2016年第2期4卷 37-67页

作者： David c.Brown Sten Tornegrd joseph Kolis Snake creek Lasers LLC clemson University Department of Chemistry

Using cryogenic laser technology, it is now possible to design and demonstrate lasers that have concomitant high average and peak powers, with near-diffraction-limited beam quality. We refer to these new laser systems as hAPP lasers. In this paper, we review important laser crystal materials properties at cryogenic temperature, with an emphasis on Yb lasers, and discuss the important design considerations, including the laser-induced damage threshold, nonlinear effects and thermal effects. A comprehensive model is presented to describe diode pulsed pumping with arbitrary duration and repetition rate, and is used with the Frantz–Nodvik equation to describe, to first order, the performance of hAPP laser systems. A computer code with representative results is also described.

关键词： cryogenic lasers high-average-power lasers high-peak-power lasers ultrafast lasers Yb lasers

Axonal growth inhibitors and their receptors in spinal cord injury:from biology to clinical translation

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Neural Regeneration Research 2023年第12期18卷 2573-2581页

作者： Sílvia Sousa chambel célia Duarte cruz Experimental Biology Unit Department of BiomedicineFaculty of Medicine of PortoUniversity of PortoPortoPortugal Translational NeuroUrology Instituto de Investigação e Inovação em Saúde-i3S and IBMCUniversidade do PortoPortoPortugal

Axonal growth inhibitors are released during traumatic injuries to the adult mammalian central nervous system, including after spinal cord injury. These molecules accumulate at the injury site and form a highly inhibitory environment for axonal regeneration. Among these inhibitory molecules, myelinassociated inhibitors, including neurite outgrowth inhibitor A, oligodendrocyte myelin glycoprotein, myelin-associated glycoprotein, chondroitin sulfate proteoglycans and repulsive guidance molecule A are of particular importance. Due to their inhibitory nature, they represent exciting molecular targets to study axonal inhibition and regeneration after central injuries. These molecules are mainly produced by neurons, oligodendrocytes, and astrocytes within the scar and in its immediate vicinity. They exert their effects by binding to specific receptors, localized in the membranes of neurons. Receptors for these inhibitory cues include Nogo receptor 1, leucine-rich repeat, and Ig domain containing 1 and p75 neurotrophin receptor/tumor necrosis factor receptor superfamily member 19(that form a receptor complex that binds all myelin-associated inhibitors), and also paired immunoglobulin-like receptor B. chondroitin sulfate proteoglycans and repulsive guidance molecule A bind to Nogo receptor 1, Nogo receptor 3, receptor protein tyrosine phosphatase σ and leucocyte common antigen related phosphatase, and neogenin, respectively. Once activated, these receptors initiate downstream signaling pathways, the most common amongst them being the Rho A/ROcK signaling pathway. These signaling cascades result in actin depolymerization, neurite outgrowth inhibition, and failure to regenerate after spinal cord injury. currently, there are no approved pharmacological treatments to overcome spinal cord injuries other than physical rehabilitation and management of the array of symptoms brought on by spinal cord injuries. however, several novel therapies aiming to modulate these inhibitory prot

关键词： chondroitin sulphate proteoglycans collapsin response mediator protein 2 inhibitory molecules leucine-rich repeat and Ig domain containing 1 leucocyte common antigen related myelin-associated glycoprotein neurite outgrowth inhibitor A Nogo receptor 1 Nogo receptor 3 oligodendrocyte myelin glycoprotein p75 neurotrophin receptor Plexin A2 Ras homolog family member A/Rho-associated protein kinase receptor protein tyrosine phosphataseσ repulsive guidance molecule A spinal cord injury tumour necrosis factor receptor superfamily member 19

Growth Kinetics of Nanocrystals and Nanorods by Employing Small-angle X-ray Scattering (SAXS) and Other Techniques

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Journal of Materials Science & Technology 2008年第4期24卷 615-627页

作者： Kanishka BISWAS Neenu VARGhESE c.N.R.Rao chemistry and Physics of Materials Unit DST Nanoscience Unit and CSIR Centre of Excellence in ChemistryJawaharlal Nehru Centre for Advanced Scientific ResearchJakkur P.O.Bangalore 560064India Solid State and Structural Chemistry UnitIndian Institute of ScienceBangalore 560012India chemistry and Physics of Materials Unit DST Nanoscience Unit and CSIR Centre of Excellence in ChemistryJawaharlal Nehru Centre for Advanced Scientific ResearchJakkur P.O.Bangalore 560064India

In this article, we report the results of our detailed investigations of the growth kinetics of zero-dimensional nanocrystals as well as one-dimensional nanorods by the combined use of small angel X-ray scattering （SAXS）, transmission electron microscopy （TEM） along with other physical techniques. The study includes growth kinetics of gold nanocrystals formed by the reduction of hAucl4 by tetrakis（hydroxymethyl） phosphonium chloride in aqueous solution, of cdSe nanocrystals formed by the reaction of cadmium stearate and selenium under solvothermal conditions, and of ZnO nanorods formed by the reaction of zinc acetate with sodium hydroxide under solvothermal conditions in the absence and presence of capping agents. The growth of gold nanocrystals does not follow the diffusion-limited Ostwald ripening, and instead follows a Sigmoidal rate curve. The heat change associated with the growth determined by isothermal titration calorimetry is about 10 kcal·mol^-1 per I nm increase in the diameter of the nanocrystals. In the case of cdSe nanocrystals also, the growth mechanism deviates from diffusion-limited growth and follows a combined model containing both diffusion and surface reaction terms. Our study of the growth kinetics of uncapped and poly（vinyl pyrollidone）（PVP）-capped ZnO nanorods has yielded interesting insights. We observe small nanocrystals next to the ZnO nanorods after a lapse of time in addition to periodic focusing and defocusing of the width of the length distribution. These observations lend support to the diffusion-limited growth model for the growth of uncapped ZnO nanorods. Accordingly, the time dependence on the length of uncapped nanorods follows the L3 law as required for diffusion-limited Ostwald ripening. The PVP-capped nanorods, however, show a time dependence, which is best described by a combination of diffusion （L^3） and surface reaction （L^2） terms.

关键词： Growth kinetics Gold nanocrystals cdSe nanocrystals ZnO nanorods Small angle X-ray scattering Transmission electron microscopy Ostwald ripening and sigmoidal growth