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Structure and magnetic properties of melt-spun Sm-Fe-Nb ribbons and their nitrides

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Rare Metals 2018年第3期37卷 232-236页

作者： Wen-Long Yan Yang Luo Dun-Bo Yu Gui-Yong wu Ning-Tao quan Yuan-Fei Yang Hai-Jun Peng zi-Long Wang National Engineering Research Center for Rare Earth Materials General Research Institute for Nonferrous MetalsGrirem Advanced Materials Co. Ltd.

SmFe（10-x）Nbx（x = 0, 0.1, 0.2, 0.3） ribbons and their nitrides were prepared by melt-spinning, followed by annealing and subsequent nitriding. The structure and magnetic properties were investigated by means of X-ray diffraction（XRD） using the Rietveld method, vibrating sample magnetometer（VSM）, transmission electron microscope（TEM） and Mossbauer spectroscopy. XRD analysis shows that the addition of Nb can impede the precipitation of Sm2 Fe（17） and a-Fe phases and the Nb atoms occupy 2 e site in the alloys. At 300 K, the mean hyperfine fields of 2 e site are 29.58 T with Nb doping at x = 0.1 and the corresponding Curie temperature is 552 K. The optimal properties of remanence of Br = 0.9 T, intrinsic coercivity of H（cj）= 741.5 kA·m^-1, and maximum magnetic energy product of（BH）（max）= 124.2 kJ·m-（-3） are gained at x = 0.10 in the nitrides.

关键词： Melt-spinning SmFe10-xNbx powders Magnetic properties XRD Rietveld Mssbauer spectroscopy

Two-Dimensional Animal-Like Fractals in Thin Films

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Chinese Physics Letters 1996年第2期13卷 121-124页

作者： GAO Hong-jun XUE Zeng-quan wu quan-de PANG Shi-jin Beijing Laboratory of Vacuum Physics Chinese Academy of SciencesBeijing 100080 Department of Radio-Electronics Peking UniversityBeijing 100871

we present a few unique animal-like fractal patterns in ionized-clnster-beam deposited fullerene-tetracyanoquinodimethane thin *** fractal patterns consisting of animal-like aggregates such as"fishes"and"quasi-seahorses"have been characterized by transnission electron *** results indicate that the sall aggregates ofthe aninmal-like body are composed of many single crystals whose crystalline directions are generally *** formation of tle fractal patterns can be attributed to the cluster-diffusion-lirnited aggregation.

关键词： aggregation fractal crystalline

Effect of interface behaviour on damage and instability of PBX under combined tension-shear loading

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Defence Technology（防务技术） 2023年第5期23卷 137-151页

作者： quan-zhi Xia Yan-qing wu Feng-lei Huang State Key Laboratory of Explosion Science and Technology Beijing Institute of TechnologyBeijing100081PR China

To study the effect of interface behaviour on the mechanical properties and damage evolution of PBX under combined tension-shear loading, the present work establishes the numerical model of a PBX three-phase hybrid system, which introduces a nonlinear plastic damage cohesion model to study the mechanical response and damage process. The parameters in the model were fitted and *** the crack growth rate as the feature, the damage state in each stage was determined, and the damage instability criterion was given. The effects of interfacial tensile strength and shear strength on the damage process of PBX were studied. On this basis, serrated and hemispherical structures interface of PBX has been developed, which affects the damage process and instability during the loading *** results indicate that damage state response of PBX experiences the process of stable load bearing,unstable propagation, and complete failure. At the critical moment of instability, the overall equivalent effective strain of material reaches 3024 με and instability loading displacement reaches 0.39 mm. The increase of interfacial tensile strength and shear strength significantly inhibits the damage of PBX. The effect of interfacial shear strength on critical instability of PBX is approximately 1.7 times that of the interfacial tensile strength. Further, interface opening along the normal direction is the main damage form at the interface. Serrated and hemispherical rough interfaces can significantly inhibit propagation of cracks, and the load bearing capacity is improved by 22% and 9.7%, respectively. Appropriate improvement of the roughness of the interface structure can effectively improve the mechanical properties. It is significantly important to have a better understanding of deformation, damage and failure mechanisms of PBX and to improve our predictive ability.

关键词： PBX explosives Interface behaviour Damage Instability Crack propagation

Pulmonary alveolar proteinosis complicated with nocardiosis: A case report and review of the literature

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World Journal of Clinical Cases 2021年第12期9卷 2874-2883页

作者： Xiao-Kang wu quan Lin Department of Respiratory and Critical Care Medicine The First Affiliated Hospital of Wenzhou Medical UniversityWenzhou 325015Zhejiang ProvinceChina

BACKGROUND Pulmonary alveolar proteinosis(PAP)is a pulmonary syndrome wherein large volumes of phospholipid and protein-rich surfactants accumulate within the *** forms include primary(auto-immune PAP),secondary,and *** is a form of suppurative disease induced upon infection with bacteria of the Nocardia ***,cases of PAP complicated with Nocardia infections are rare,regardless of ***,as such,they are easily overlooked or *** describe,here,the case of a patient suffering from simultaneous primary PAP and *** SUMMARY A 45-year-old Chinese man,without history of relevant disease,was admitted to our hospital on August 8,2018 to address complaints of activity-related respiratory exertion and cough lasting over 6 *** computed tomography(CT)revealed diffuse bilateral lung infiltration with local consolidation in the middle right lung *** transbronchial lung biopsy and CT-guided lung biopsy led to a diagnosis of primary PAP(granulocyte-macrophage colonystimulating factor antibody-positive)complicated with nocardiosis(periodic acid-Schiff-positive).After a 6 mo course of anti-infective treatment(sulfamethoxazole),the lesion was completely absorbed,such that only fibrous foci remained,and the patient exhibited significant symptom *** also showed improvement in pulmonary function and the CT imaging findings of *** whole-lung lavage has been conducted to *** case highlights that active anti-nocardia treatment may effectively improve the symptoms and alleviate PAP in patients with PAP and nocardia,possibly reducing the need for whole-lung *** When evaluating patients presenting with PAP and pulmonary infections, thepotential for nocardiosis should be considered.

关键词： Pulmonary alveolar proteinosis Nocardiosis Vitek mass spectroscopy Whole-lung lavage Case report

Seepage field distribution and water inflow laws of tunnels in water-rich regions

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Journal of Mountain Science 2022年第2期19卷 591-605页

作者： LI Zheng CHEN zi-quan HE Chuan MA Chun-chi DUAN Chao-ran School of Civil Engineering Chongqing UniversityChongqing 400045China Key Laboratory of Transportation Tunnel Engineering Ministry of EducationSouthwest Jiaotong UniversityChengdu 610031China Chongqing University Industrial Technology Research Institute Chongqing 401329China Chongqing City Construction Investment(Group)Co. LtdChongqing 400023China State Key Laboratory of Geohazard Prevention and Geoenvironment Protection Chengdu University of TechnologyChengdu 610059China School of Civil Engineering Changzhou Institute of TechnologyChangzhou 213032China

Currently,the water inrush hazards during tunnel construction,the water leakage during tunnel operation,and the accompanying disturbances to the ecological environment have become the main problems that affect the structural safety of tunnels in water-rich *** this paper,a tunnel seepage model testing system was used to conduct experiments of the grouting circle and primary support with different permeability *** influences of the supporting structures on the water inflow laws and the distribution of the water pressure in the tunnel were *** the decrease in the permeability coefficient of the grouting circle or the primary support,the inflow rate of water into the tunnel showed a non-linear decreasing *** comparison,the water inflow reduction effect of grouting circle was much better than that of primary *** the increase of the permeability coefficient of the grouting ring,the water pressure behind the primary lining increases gradually,while the water pressure behind the grouting ring ***,the grouting of surrounding rock during the construction of water-rich tunnel can effectively weaken the hydraulic connection,reduce the influence range of seepage,and significantly reduce the decline of ***,the seepage tests at different hydrostatic heads and hydrodynamic heads during tunnel operation period were also *** the hydrostatic head decreased,the water pressure at each characteristic point decreased approximately linearly,and the water inflow rate also had a gradual downward *** the action of hydrodynamic head,the water pressure had an obvious lagging effect,which was not conducive to the stability of the supporting structures,and it could be mitigated by actively regulating the drainage *** with the hydrostatic head,the hydrodynamic head could change the real-time rate of water inflow to the tunnel and broke the dynamic balance between the water pressure and water inflow

关键词： Water-rich tunnel Seepage field distribution Water inflow law Construction period Operation period

Hoxc13/β-catenin Correlation with Hair Follicle Activity in Cashmere Goat

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Journal of Integrative Agriculture 2012年第7期11卷 1159-1166页

作者： wu Jiang-hong ZHANG Yan-jun ZHANG Jia-xin CHANG zi-li LI Jin-quan YAN Zu-wei Husile ZHANG Wen-guang Key Laboratory of Animal Genetics Breeding and Reproduction Inner Mongolian Autonomous Region Hohhot 010018 P.R.China College of Animal Science Inner Mongolia Agricultural University Hohhot 010018 P.R.China College of Science Inner Mongolia Agricultural University Huhhot 010018 P.R.China

Seasonal hair follicle activity and fibre growth in some Cashmere-bearing goats （Caprus hircus） is a cyclic process that is well characterized morphologically but understood incompletely at the molecular level. As an initial step in discovering regulators in hair-follicle activity and cycling, we used qPCR to investigate 19 genes expression in Cashmere goat side skin from 12 mon. Many of these genes may be associated with the hair follicle development-relevant genes （HFDRGs） in the literature. Here we show that Hoxc13/β-catenin gene associated with the follicle activity. In addition, Hoxc13 was found to be expressed with an drastic increase between July and November for melatonin treatments. To further investigate the role of Hoxcl3 on HFDRGs, fibroblasts and keratinocytes from Cashmere goat skin were transfected with p-ECFP- Hoxc13. The result suggested that overexpression ofHoxcl3 gene decreased HFDRGs with negative role for hair follicle development and increase HFDRGs with positive role for hair follicle development in vitro. These findings provide data on the Hoxc13 expression profile of normal Cashmere goat skin and Cashmere goat skin with melatonin treatment, and demonstrate hair-follicle-activity dependent regulation of Hoxc13 expression.

关键词： Hoxcl3 β-catenin Cashmere goat hair follicle activity cycle

Experimental Study on Conversion Characteristics of Dual-Mode OWC Models Appropriate for Voyaging

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China Ocean Engineering 2023年第2期37卷 247-257页

作者： wu Bi-jun ZHANG Fu-ming QIN zi-zhen wu Heng-yu RAO Xiang Guangzhou Institute of Energy Conversion Chinese Academy of SciencesGuangzhou 510640China Southern Marine Science and Engineering Guangdong Laboratory(Guangzhou) Guangzhou 511458China Key Laboratory of Renewable Energy CASGuangzhou 510640China University of Chinese Academy of Sciences Beijing 100049China South China Normal University Guangzhou 510631China University of Science and Technology of China Hefei 230026China

Freely movable wave energy converters(WECs) will greatly improve their adaptability to the marine *** this paper, a dual-mode oscillating water column(OWC) WEC with potential sailing capability is proposed. By opening and closing a gate on the side facing the waves, the WEC converts wave energy in the vertical duct(called VD mode) with low sailing resistance or in the backward bend duct(called BBD mode) with high sailing resistance.A small model and a medium model were designed and manufactured. The capture width ratio(CWR) of the small model in the two modes was experimentally studied. The CWR under bidirectional airflow and conversion characteristics under unidirectional airflow of the medium model in the BBD mode were obtained. Tests of the small model show that the peak CWR is 145.2% under regular waves and 90.1% under random waves in BBD mode, and in VD mode the peak CWR is about 60% of that in the BBD mode. Tests of the medium model show that the peak CWR is 228.96% under regular waves, the maximum wave-to-battery efficiency is 63.36% under regular waves and 30.17%under random waves, respectively.

关键词： wave energy oscillating water column(OWC) capture width ratio(CWR) wave-to-battery conversion efficiency

SDOG-based multi-scale 3D modeling and visualization on global lithosphere

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Science China Earth Sciences 2012年第6期55卷 1012-1020页

作者： YU JieQing wu LiXin zi GuoJie GUO ZengZhang State Key Laboratory of Earth Surface Processes and Resource Ecology Beijing Normal University Beijing 100875 China Key Laboratory of Environment Change and Natural Disaster Beijing Normal University Beijing 100875 China School of Surveying and Land Information Engineering Henan Polytechnic Universit） Jiaozuo 454000 China

The structure of global lithosphere is very important to the scientific researches of tectonic movement, geodynamic process, mantle convection, resource exploration, and disaster prevention and reduction. Three-dimensional (3D) spatial modelling and visualization is an effective tool for lithosphere researches. However, both the isoline/profile methods and the Euclidean-based 3D modelling methods cannot meet the requirement of real 3D modeling of global lithosphere, whereas the recently developed global 3D grid methods have some defects on grid design, such as grid shrinkage, overlapping, non-orthogonality, and nonlatitude-longitude consistency. In this paper, Spheroid Degenerated-Octree Grid (SDOG), a non-overlapping, non-shrinking, orthogonal, latitude-longitude consistent grid in the spheroidal manifold space, was chosen as the basic grid for global lithosphere 3D modeling and visualization. The SDOG-based methods of spatial representation and modelling of lithosphere were proposed. A multi-scale model of lithosphere was designed, and the multi-scale modeling and multi-mode visualization were realized at the full advantages of SDOG in multi-hierarchical and multi-resolution and the properties of lithosphere in multi-semantic. It shows that (1) the SDOG-based method has not only overcome the defects of the current global 3D grid, but also reflected the spherical features of lithosphere more realistically and naturally than the traditional methods, providing a novel solution for global modeling, numeric simulating, and data sharing of lithosphere; and (2) more detailed plates division, more precise geo-layer structure, plates boarder and surface concave-convex, and more rich lithosphere properties are revealed as the scale-model moves on.

关键词： Spheroid Degenerated-Octree Grid (SDOG) lithosphere 3D manifold modeling visualization global 3D grid

Towards Automatic Generation of As-built BIM:3D Building Facade Modeling and Material Recognition from Images

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International Journal of Automation and computing 2016年第4期13卷 338-349页

作者： Jun Yang Zhong-Ke Shi zi-Yan wu School of Mechanics Civil Engineering and Architecture Northwestern Polytechnical University Xi'an 710072 China School of Automation Northwestern Polytechnical University Xi'an 710072 China

As-built building information model （BIM） is an urgent need of the architecture, engineering, construction and facilities management （AEC/FM） community. However, its creation procedure is still labor-intensive and far from maturity. Taking advantage of prevalence of digital cameras and the development of advanced computer vision technology, the paper proposes to reconstruct a building facade and recognize its surface materials from images taken from various points of view. These can serve as initial steps towards automatic generation of as-built BIM. Specifically, 3D point clouds are generated from multiple images using structure from motion method and then segmented into planar components, which are further recognized as different structural components through knowledge based reasoning. Windows are detected through a multilayered complementary strategy by combining detection results from every semantic layer. A novel machine learning based 3D material recognition strategy is presented. Binary classifiers are trained through support vector machines. Material type at a given 3D location is predicted by all its corresponding 2D feature points. Experimental results from three existing buildings validate the proposed system.

关键词： As-built Building information models (BIM) image reconstruction modeling material recognition three dimensional