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Investigation of high power laser coatings

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光学精密工程 2005年第4期13卷 471-479页

作者： SHAO j.an-da FAN Zheng-xiu R＆D Center for Optical Thin Film Coating Technology Shanghai Institute of Optics and Fine Mechanics Chinese Academy of Sciences Shanghai 201800 China

High laser-induced damage threshold and large aperture were focuses on the studies of high power laser coatings. This paper reports the research activities at our center. Several measures were developed for evaluating characters of laser damage, including determination of laser induced damage threshold and detection of absorption based on surface thermal lensing technique. Defect was deemed to be the initial source of laser damage, and was the main factor restricting the laser damage resistance of optical coatings. The contribution of several kinds of typical defects to laser damage was analyzed, and some deposition measures were adopted to control and eliminate the origin of defect. Furthermore, some post-treatment methods were also employed to alleviate the influence of the defect and to improve the laser damage resistance. Correction mask was introduced to improve the thickness uniformity, and the thickness uniformity can be amended to less than 1% in the range of Φ650 mm. Preliminary investigation related to surface deformation was also conducted.

关键词：激光涂覆技术 LidT 吸收能力激光器

Giovanni Antonio Bazzi, Allegories of Love： Emblematic Ardor

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Cultural and Religious Studies 2017年第5期5卷 277-313页

作者： Liana De Girolami cheney SIEALE University of Coruna Spain

Giovanni Antonio Bazzi （1477-1549）, also known as I1 Sodoma, was a Milanese painter who developed his mature style in Siena during the early Cinquecento. Between 1505 and 1510, under the tutelage of the Chigi and Petrucci families, Bazzi depicted mythological paintings focusing on the personifications of love both terrestrial and celestial. This paper looks at two such works. In one, there hangs on a sycamore tree a classical cartello with the Latin inscription Celestes, meaning celestial or heavenly, providing the title for the painting Amore Celeste （Celestial Love, Figure 3）. A woman, as the personification of love, stands in front of two altars. She ignites one urn with fire and at the same time pours water over another burning fire. In the second work, a tondo with the theme of Terrestrial Love and Celestial Love, Bazzi considered the mischievousness of Venus＇ children Eros and Anteros （Figure 12）. These paintings are mythological and poetical delights with complex symbolism, here analyzed in terms of their iconography in relation to classical influences and Renaissance Neoplatonic love or furor divinus. The paradoxical quest of Renaissance Neoplatonic love was to fuse pagan love with Christian love. For the humanists of the time （Bembo, Colonna, Poliziano, Ficino and Pico） this moral dilemma was a philosophical puzzle, but for artists （Botticelli, Nicoletto da Modena, Pinturicchio and Bazzi） the theme was a pictorial challenge.

关键词： Allegories love iconography poetry Neoplatonism Sienese patronage Sodoma

Wettability of silicon carbide ceramic by Al_2O_3/Dy_2O_3 and Al_2O_3/Yb_2O_3 systems

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j.urnal of Rare Earths 2013年第6期31卷 634-638页

作者： j.A.da Silva B.M.Moreschi G.C.R.Garcia S.Ribeiro Department of Materials Engineering (DEMAR) Engineering School of Lorena (EEL)Pólo Urbo IndustrialGleba AI6CP 11612608-970LorenaSPBrazil

Wettability is an important phenomenon in the liquid phase sintering of silicon carbide （SiC） ceramics. This work involved a study of the wetting of SiC ceramics by two oxide systems, Al2O3 /Dy2O3 and Al2O3 /Yb2O3, which have so far not been studied for application in the sintering of SiC ceramics. Five mixtures of each system were prepared, with different compositions close to their respective eutectic ones. Samples of the mixtures were pressed into cylindrical specimens, which were placed on a SiC plate and subj.cted to temperatures above their melting points using a graphite resistance furnace. The behavior of the melted mixtures on the SiC plate was observed by means of an imaging system using a CCD camera and the sessile drop method was employed to determine the contact angle, the parameter that measures the degree of wettability. The results of variation in the contact angle as a function of temperature were plotted in graphic form which showed that the curves displayed a fast decline and good spreading. All the samples of the two systems presented final contact angles of 40o to 10o indicating their good wetting on SiC in the argon atmosphere. The melted/solidified area and interface between SiC and melted/solidified phase were evaluated by scanning electron microscopy （SEM） and their crystalline phases were identified by X-ray diffraction （DRX）. The DRX analysis showed that Al2O3 and RE2O3 reacted and formed the Dy3Al5O12 （DyAg） and Yb3Al5O12 （YbAg） phases. The results indicated that the two systems had a promising potential as additives for the sintering of SiC ceramics.

关键词： liquid-phase sintering silicon carbide rare earth oxide wettability contact angle

The corpus cavernosum after treatment with dutasteride or finasteride： a histomorphometric study in a benign prostatic hyperplasia rodent model

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Asian j.urnal of Andrology 2018年第5期20卷 505-510页

作者： Marcello H A da Silva Waldemar S Costa Francisco j.B Sampaio Diogo B De Souza Urogenital Research Unit Rio de Janeiro State University Rio de Janeiro RJ 20551-030 Brazil

Erectile dysfunction is a common side effect of finasteride and dutasteride treatments. The obj.ctive of this study was to investigate the structural changes in the penis using a benign prostatic hyperplasia （BPH） rodent model treated with dutasteride or finasteride. Sixty male rats were divided into the following groups： C, untreated control rats; C ＋ D, control rats receiving dutasteride; C ＋ F, control rats receiving finasteride; H, untreated spontaneously hypertensive rats （SHRs）; H ＋ D, SHRs treated with dutasteride; and H ＋ F, SHRs treated with finasteride. Treatments were performed for 40 days, and penises were collected immediately thereafter. The organs were analyzed using histomorphometric methods to determine the cross-sectional penile area, as well as the surface density （Sv） of smooth muscle fibers, connective tissue, elastic system fibers, and sinusoidal spaces of the corpus cavernosum. The results were compared using a one-way ANOVA with Bonferroni＇s posttest. Groups C ＋ D and C ＋ F had a significantly smaller penile cross-sectional area, but more elastic system fiber Sv compared to Group C. Group C ＋ D showed less smooth muscle Sv, and Group H showed more connective tissue but a smaller sinusoidal space Sv in the corpus cavernosum compared to Group C. Groups H ＋ D and H ＋ F had less smooth muscle Sv than Group H. Group H ＋ D also had more connective tissue and elastic system fiber Sv than Group H. Both dutasteride and finasteride promoted penile modifications in the control rat penis, although this affect was ~reater in Group H animals. In this rodent model, dutasteride was the drug that most affected the corpus cavernosum.

关键词： animal models benign prostatic hyperplasia dutasteride erectile dysfunction finasteride penis

Analysis of hydrodynamic effects on biofilm thickness in fluidized-bed tapered bioreactors

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Particuology 2021年第5期19卷 48-57页

作者： daniela Maria Koerich Leonardo Machado da Rosa Chemical Engineering Department University of Blumenau(FURB)3250 Sao Paulo Street89030-000 BlumenauSanta CatarinaBrazil

Fluidized beds in tapered geometries provide advantages such as a broad range of optimum operating ***,the dynamics of the flow inside these bioreactors is significantly more complex,as they promote non-uniform bioparticles *** this end,the CFD technique can give a detailed description of the flow in the ***,the aim of this work is to assess the influence of the hydrodynamic on the steady-state biofilm thickness through numerical simulations of liquid–solid fluidized *** geometries of tapered bioreactors in the operating conditions used to develop *** were run to solve the two-phase RANS equations using the open-source software OpenFOAM in *** SST k−ω model was used to estimate the turbulent features of the *** and bioparticles distribution inside the reactor were analyzed for different inlet velocities,while bioparticles collision frequency and shear stresses were evaluated for various operating *** comparison between the turbulent kinetic energy and the granular temperature indicated that the fluid flow is more turbulent than the bioparticles *** hydrodynamics influence on the steady-state biofilm thickness was assessed,and results led to the conclusion that biofilm is more sensitive to hydrodynamic shear stress than bioparticles collisions.

关键词： Liquid-solid fluidization Shear stress Particles collisions Computational fluid dynamics Biofilm Tapered bioreactors

l_(1)-based calibration of POD-Galerkin models of two-dimensional unsteady flows

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Chinese j.urnal of Aeronautics 2021年第1期34卷 226-236页

作者： Riccardo RUBINI da.ide LASAGNA Andrea da RONCH Faculty of Engineering and Physical Sciences University of SouthamptonSouthampton SO171BJUnited Kingdom

This paper discusses a physics-informed methodology aimed at reconstructing efficiently the fluid state of a ***,the generation of an accurate reduced order model of twodimensional unsteady flows from data leverages on sparsity-promoting statistical learning *** cornerstone of the approach is l_(1) regularised regression,resulting in sparselyconnected models where only the important quadratic interactions between modes are *** original dynamical behaviour is reproduced at low computational costs,as few quadratic interactions need to be *** approach has two key ***,interactions are selected systematically as a solution of a convex optimisation problem and no a priori assumptions on the physics of the flow are ***,the presence of a regularisation term improves the predictive performance of the original model,generally affected by noise and poor data *** cases are for two-dimensional lid-driven cavity flows,at three values of the Reynolds number for which the motion is chaotic and energy interactions are scattered across the *** is found that:(A)the sparsification generates models maintaining the original accuracy level but with a lower number of active coefficients;this becomes more pronounced for increasing Reynolds numbers suggesting that extension of these techniques to real-life flow configurations is possible;(B)sparse models maintain a good temporal stability for *** methodology is ready for more complex applications without modifications of the underlying theory,and the integration into a cyberphysical model is feasible.

关键词： Computational methods Dynamical systems Lid-driven cavity L_(1)-based regression Reduced order models Sparsification Stabilization of ROMs

Cyclic load testing of pre-stressed rock anchors for slope stabilization

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j.urnal of Mountain Science 2016年第1期13卷 126-136页

作者： ZHENG da LIU Fang-zhou j. Neng-pan FROST j.da.id HUANG Run-qiu State Key Laboratory of Geohazard Prevention and Geoenvironment Protection Chengdu University of Technology School of Civil and Environmental Engineering Georgia Institute of Technology

The obj.ctive of this research was to assess the characteristics of seismic induced damage and the deformation patterns of pre-stressed cement-grouted cables that are used for rock slope stabilization proj.cts subj.cted to quasi-static cyclic *** experimental configuration includes the installation of 15 pre-stressed cables in a slope model made of concrete blocks(theoretically rigid rock mass) on top of a pre-existing sliding *** study showed that:(i) The pre-stressed cables exhibited great seismic *** displacement of the model blocks was observed after the complete loss of the initial pre-stress load under continued applied cyclic loads and exceedance of the state of equilibrium,which implies the higher the initial pre-stress load,the better the seismic performance of the rock anchor;(ii) The failure of the pre-stressed cables was due to fracture at the connection of the tendons and cable heads under cyclic *** sequence of failure had a distinct *** was first observed at the upper row of cables,which experienced the most severe damage,including the ej.ction of cable *** evidence of de-bonding was observed during the cyclic loading;(iii) The stress distribution of the bond length for pre-stressed cables was highly *** stress concentrations were observed at both the fixed end and the free end of the bond length both before and immediately after the state of equilibrium is *** results obtained can be used to evaluate the overall performance of pre-stressed rock anchors subj.ct to seismic loading and their potential as rockfall prevention and stabilization measures.

关键词： stabilization rock sliding stressed cable blocks anchor ej.ction implies experienced

Historic accounts of Mansonella parasitaemias in the South Pacific and their relevance to lymphatic filariasis elimination efforts today

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Asian Pacific j.urnal of Tropical Medicine 2016年第3期9卷 201-207页

作者： j.Lee Crainey Tullio Romao Ribeiro da Silva Sergio Luiz Bessa Luz Ecologia de Doencas Transmissiveis na Amazonia Instituto Leonidas e Maria Deane-Fiocruz Amazonia Rua Terezina

There are two species of filarial parasites with sheathless microfilariae known to commonly cause parasitaemias in humans:Mansonella perstans and Mtinsonella *** most contemporary accounts of the distribution of these parasites,neither is usually considered to occur anywhere in the Eastern ***,Sir Patrick Manson,who first described both parasite species,recorded the existence of sheathless sharp-tailed Mansonella ozzardilike parasites occurring in the blood of natives from New Guinea in each and every version of his manual for tropical disease that he wrote before his death in ***'s reports were based on his own identifications and were made from at least two independent blood sample collections that were taken from the *** region Mansonella perstans parasitaemias were also later(in 1923) reported to occur in New Guinea and once before this(in 1905) in *** Mansonella-parasilaernias are generally regarded as benign,they are thought to be of public health importance because they can affect the epidemiological monitoring of other filarial *** this article,we reviewed the historic literature concerning Pacific-origin Mansonella-parasitaemias in an attempt to explain how,despite repeated reports of Pacificregion Mansonella-parasilaemias,by as early as the 1970 s,the WHO had arrived at the presentday view that Wuchereria bancrofti is the only cause of filarial parasitaemias in Papua New *** have also evaluated the evidence supporting the contemporary existence of Pacificarea parasitaemia-causing Mansonella parasites and assessed the relevance such parasites could have for present-day lymphatic filariasis elimination efforts in the region.

关键词： Mansonella ozzardi Mansonella perstans Wuchereria bancrofti Papua New Guinea Lymphatic filariasis Global Programme to Eliminate Lymphatic Filariasis

Small-scale self-driving cars:A systematic literature review

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j.urnal of Traffic and Transportation Engineering(English Edition) 2024年第2期11卷 271-292页

作者： Felipe Caleffi Lauren da Silva Rodrigues j.ice da Silva Stamboroski Brenda Medeiros Pereira Autonomous Vehicles Laboratory Federal University of Santa MariaCachoeira do Sul 96503-205Brazil Mobility and Logistics Laboratory Federal University of Santa MariaCachoeira do Sul 96503-205Brazil

The autonomous vehicle(AV)technology has the potential to significantly improve safety and efficiency of the transportation and logistics ***-scale AV testing is limited by time,space,and cost,while simulation-based testing often lacks the necessary accuracy of AV and environmental *** recent years,several initiatives have emerged to test autonomous software and hardware on scaled *** systematic literature review provides an overview of the literature surrounding small-scale self-driving cars,summarizing the current autonomous platforms deployed and focusing on the software and hardware developments in this *** studies published in English-language j.urnals or conference papers that present small-scale testing of self-driving cars were *** of Science,Scopus,Springer Link,Wiley,ACM Digital Library,and TRid databases were used for the literature *** systematic literature search found 38 eligible *** gaps in the reviewed papers were identified to provide guidance for future *** key takeaway emerging from this manuscript are:(i)there is a need to improve the models and neural network architectures used in autonomous driving systems,as most papers present only preliminary results;(ii)increasing datasets and sharing databases can help in developing more reliable control policies and reducing bias and variance in the training process;(iii)small-scaled vehicles to ensure safety is a maj.r benefit,and incorporating data about unsafe driving behaviors and infrastructure problems can improve the accuracy of predictive models.

关键词： Self-driving car Autonomous vehicle Small-scale vehicle Systematic literature review