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单通道和多通道毛细管光学元件-技术发展水平和应用(英文) 被引量:2
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作者 A Bjeoumikhov R Wedell S Bjeoumikhova 《光学精密工程》 EI CAS CSCD 北大核心 2007年第12期1932-1945,共14页
毛细管光学元件在X射线分析中的应用已有20多年的历史,在这段时间里,毛细管光学元件的制作技术发生了很大的变化。上世纪90年代初,使用的是组装的毛细管光学元件,目前,集成的多通道毛细管光学元件已广泛地应用于市场销售的X射线分析设... 毛细管光学元件在X射线分析中的应用已有20多年的历史,在这段时间里,毛细管光学元件的制作技术发生了很大的变化。上世纪90年代初,使用的是组装的毛细管光学元件,目前,集成的多通道毛细管光学元件已广泛地应用于市场销售的X射线分析设备中。这些元件的毛细管直径在微米量级,其光学性质可以根据几何光学的光线追迹计算进行描述。最近,由于多通道毛细管制作技术的改进,已成功制成了200 nm及以下通道尺寸的毛细管光学元件。在这样小的通道尺寸下,观察到了X射线辐射的波动效应。最后文章介绍了毛细管光学元件在X射线微荧光分析和微衍射方面的应用。 展开更多
关键词 X射线毛细管光学元件 波动特性 纳米毛细管 X射线分析
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Sea Urchin Spines as a Model-System for Permeable,Light-Weight Ceramics with Graceful Failure Behavior.Part Ⅱ.Mechanical Behavior of Sea Urchin Spine Inspired Porous Aluminum Oxide Ceramics under Compression 被引量:1
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作者 V.Presser C.Kohler +5 位作者 Z.Zivcová C.Berthold K.G.Nickel S.Schultheiβ E.Gregorová W.Pabst 《Journal of Bionic Engineering》 SCIE EI CSCD 2009年第4期357-364,共8页
Sea urchin spines were chosen as a model system for biomimetic ceramics obtained using starch-blended slip casting. Porous alumina ceramics with cap-shaped layers with different alternating porosities were found to ha... Sea urchin spines were chosen as a model system for biomimetic ceramics obtained using starch-blended slip casting. Porous alumina ceramics with cap-shaped layers with different alternating porosities were found to have superior fracture behavior under bulk compression compared to ceramics with uniform porosity.They fail in a cascading manner,absorbing high amounts of energy during extended compression paths.The porosity variation in an otherwise single phase material mimicks the architectural microstructure design of sea urchin spines of Heterocentrotus mammillatus,which are promising model materials for impact protection. 展开更多
关键词 biomimetic engineering sea urchin spines porous alumina ceramics starch-blended slip casting mechanical behavior compression
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Non-Rotating Black Holes, Dark Matter and Dark Energy in a Unifying Theory
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作者 Antonio Holdefer 《Journal of Applied Mathematics and Physics》 2021年第7期1560-1582,共23页
The theory here developed, makes use of the decomposition of matter (mass) in different spatial frequencies k’s using spatial Fourier transforms, and the posterior use of modified inverse Fourier transforms to constr... The theory here developed, makes use of the decomposition of matter (mass) in different spatial frequencies k’s using spatial Fourier transforms, and the posterior use of modified inverse Fourier transforms to construct an accurate description of the classical Newtonian gravitational field. Introducing the concept of quantization of the spatial frequency <em>k</em>, which means allowing only discrete values, such as <em>k<sub>m</sub></em>, 2<em>k<sub>m</sub></em>, 3<em>k<sub>m</sub></em>, leads to the appearance of extra gravitational force regions that occur at distances equally spaced apart in 2π/<em>k<sub>m</sub></em>. These areas of extra gravitational force decrease inscribed in an inverse of the distance envelope (1/<em>r</em>). The value of 2π/<em>k<sub>m</sub></em> can be adjusted to be of the order of kiloparsec (kpc), being this way a plausible explanation for the effect of the dark matter since this causes practically flat rotation curves for most of the galaxies. As these regions of extra gravitational force also have adjacent areas of negative values (repulsive gravitational force), it is possible to show that any mass placed in the gravitational field far from the galaxy center will acquire, on average, a null acceleration, thereby remains the “light push,” or in other words, the “mean luminosity density” between galaxies as an explanation for the accelerating expansion of the universe, today being considered mainly due to dark energy. Along with the article, it is showed that the effect of light push is sufficient to explain the expansion of the universe. The present work also explains the nonlinear behavior of gravitational fields near massive objects such as blackholes, not contradicting the theory of general relativity, instead giving a complementary description of how black holes work, even describing the gravitational field internally to it, which is not available in the GR theory. 展开更多
关键词 Black Holes Dark Matter Dark Energy Motion Energy Accelerating Expansion of the Universe
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Production of Soybean Oil Nanoemulsion (SONE) and Evaluation of Angiogenic and Embryotoxic Activity
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作者 Tamíris Augusto Marinho Patrícia Silva Nunes +2 位作者 Paulo Roberto de Melo-Reis Mônica Rodrigues Ferreira Machado Nelson Jorge Silva Júnior 《Journal of Biomaterials and Nanobiotechnology》 2020年第3期161-178,共18页
The SONE oil/water was prepared using the pseudo-ternary phase diagram, using a low energy method with phase inversion by changing the composition. In order to optimize the preparation of SONE, three speeds were used ... The SONE oil/water was prepared using the pseudo-ternary phase diagram, using a low energy method with phase inversion by changing the composition. In order to optimize the preparation of SONE, three speeds were used in the agitator arm and two different rods. The particle size and polydispersity index were determined by Dynamic Light Scattering (DLS) and the stability test by the freeze-thaw cycle. Angiogenesis in chicken embryo egg chorioallantoic membrane and zebrafish (<em>Danio rerio</em>) embryotoxicity was performed. The lower stirring speed and propeller shaft induced smaller particle size (550.2 nm). Regarding angiogenesis, there was a statistically significant difference for all the evaluated parameters (length, caliber, junctions, and number of blood vessel complexes) and the result was higher in SONE when compared to the inhibition control (Dexamethasone), but lower than the induction control (Regederm<span style="font-family:Verdana, Helvetica, Arial;white-space:normal;background-color:#FFFFFF;"><sup>&#174;</sup></span>) and there was no statistically significant difference between SONE and distilled water. It was observed that the exposure of the zebrafish embryos to SONE caused an increase in the mortality rate dependent on time and concentration. The LC<sub>50</sub> for SONE decreased statistically with increasing exposure (p-value = 0.046). Heart rate decreased significantly with increasing concentration at all exposure times (p-value < 0.05), as a result of progressive embryo mortality. The hatching rate was late until the concentration of 0.0193 mg/mL and no hatching rate was verified from that concentration. Exposure of zebrafish embryos to different concentrations of SONE induced malformations such as spinal changes, pericardial edema and yolk sac edema, but there was no significant difference in the malformation rate of embryos exposed to SONE when compared to the control group. The SONE produced remained stable in the freeze-thaw cycle, with changes only in pH. Despite the low results for embryotoxicity, further studies are needed, aiming at the ideal formulation for angiogenesis purposes. 展开更多
关键词 Soybean Oil Angiogenesis Inducing Agents TOXICITY BIOTECHNOLOGY NANOTECHNOLOGY
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Switching of Capacitors in an Asymmetric Induction Motor with Single-Phase Power,Triggering Several Applied Loads
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作者 Prado Wellington Marcos Antonio Geraldo Caixeta Guimarães 《Journal of Energy and Power Engineering》 2020年第3期90-99,共10页
xThis study has as its objective to collaborate with the expansion in the market of electric energy in rural areas,offering as such an innovative prospect to the solution of associated problems through use of the asym... xThis study has as its objective to collaborate with the expansion in the market of electric energy in rural areas,offering as such an innovative prospect to the solution of associated problems through use of the asymmetric three-phase induction motor,supplied by a single-phase source.In this system,capacitor switching is applied during operation,while theoretical and practical results are presented for the application of this switching in a three-phase asymmetric induction motor of 20 hp. 展开更多
关键词 Startup current capacitor switching three-phase induction motor asymmetric motor power factor
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Applicability of PAVEAIR for Airport Pavement Management:Comparison between Military and Civilian Runways
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作者 Matheus Silva Oliveira Cláudia Azevedo Pereira Pollyany Cristie de Assis Farias 《Journal of Civil Engineering and Architecture》 2020年第7期360-367,共8页
Nowadays,globalization has become essential,and interconnection between people and cargo has become necessary due to international trade and investment.In this context,aviation is an important modal because of its eff... Nowadays,globalization has become essential,and interconnection between people and cargo has become necessary due to international trade and investment.In this context,aviation is an important modal because of its efficiency in security,range,and speed;however,the aerodrome infrastructure capacity is not always sized according to the demand and safety regulations required during operations.The number of runway occurrences in Brazil increased considerably since 2011.These occurrences are consequences of several contributing factors,of which runway conditions and airport infrastructure can be considered the most important;however,the quality of runways and the flight safety they provide can’t be quantified through direct statistics.Adhering to a high standard of airfield quality while also knowing airport infrastructure,a study that applies an evaluation of the Pavement Condition Index(PCI)methodology has been developed.First,the airfield pavement at a military base was analyzed and later compared to the results found in a civil airfield study done by another author.The methods used to identify distress in the pavement’s surface were based on ASTM D 5340-12,as are PCI calculations.Secondly,the system was infused into PAVEAIR-FAA(Federal Aviation Administration)to apply an airport management method at a military base to compare the results obtained by other authors for a civil airfield study,where it was intended to analyze the performance characteristics of the runway for each type use.Subsequently,one can obtain subsidies of decisions for the optimization of resources used in airfield maintenance and rehabilitation,and increase operational safety. 展开更多
关键词 PAVEMENT airfield PCI
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私营企业在西部的作用
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作者 阿萨德·贾布尔 《巴蜀质量跟踪》 2000年第22期18-19,共2页
我非常高兴今天上午能到这里来,这对我来说是一个荣誉,而且非常高兴能够参与中国的西部论坛。这个论坛是一个独特的机会,能够让政府领导者和私营投资者一起找出和讨论西部发展的战略,并且能够在这个问题上取得更大的进展。我想感谢... 我非常高兴今天上午能到这里来,这对我来说是一个荣誉,而且非常高兴能够参与中国的西部论坛。这个论坛是一个独特的机会,能够让政府领导者和私营投资者一起找出和讨论西部发展的战略,并且能够在这个问题上取得更大的进展。我想感谢四川省政府以及组委会,因为他们安排了这一重要的论坛,并且向我们在座的每一人表示了如此热烈的欢迎。 展开更多
关键词 私营企业 西部 金融体系 贷款 投资
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Stabilization of Silica Gel against Hydrolysis by Doping with F^(-) or Zr(Ⅳ)
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作者 Khaled S.Abou-El-Sherbini Peter G.Weidler +4 位作者 Detlef Schiel Mohey H.A.Amr Henning Niemann Shady El-Dafrawy Wolfgang H.Holl 《Green and Sustainable Chemistry》 2014年第1期24-32,共9页
Silica gel (SG) was synthesized via acidification of sodium silicate solution then doped with Fˉ or Zr(IV) in molar ratios of F/Si 3/100, and Zr/Si 0.75/100 and 3.75/100 and sintered at 500°C, 800°C and 100... Silica gel (SG) was synthesized via acidification of sodium silicate solution then doped with Fˉ or Zr(IV) in molar ratios of F/Si 3/100, and Zr/Si 0.75/100 and 3.75/100 and sintered at 500°C, 800°C and 1000°C. The samples were investigated by X-ray diffractometry, infrared absorption and Raman spectra, surface area measurement, and inductively coupled plasma-optical emission spectrometry-monitored silica hydrolysis. All samples are mesoporous with BET surface areas 181.5 - 523.9 m2·gˉ1. The surface area of the silica samples decreases as the sintering temperature increases. The hydrolysis process of silica decreases as the sintering temperature increases and as the surface area decreases. The pH and the type of buffer solution affect the hydrolysis of silica samples due to a SN2 reaction mechanism favored in basic media using ammonia buffer. Zr(IV) increases the stability of silica samples against the hydrolysis as confirmed by the structural investigation, surface area and silica hydrolysis. Fˉ observably decreases the silica hydrolysis process when presenting on the surface of SG. 展开更多
关键词 Silica Gel DOPING HYDROLYSIS FLUORINE ZIRCONIUM
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Hierarchical assemblies of molecular frameworks—MOF-on-MOF epitaxial heterostructures 被引量:5
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作者 Ritesh Haidar Christof Woll 《Nano Research》 SCIE EI CAS CSCD 2021年第2期355-368,共14页
Functional,porous metal-organic frameworks(MOFs)have attracted much attention as a very flexible class of crystalline,porous materials.For more advanced applications that exploit photophysical properties,the fabricati... Functional,porous metal-organic frameworks(MOFs)have attracted much attention as a very flexible class of crystalline,porous materials.For more advanced applications that exploit photophysical properties,the fabrication of hierarchical assemblies,including the creation of MOF/MOF heterointerfaces,is important.For the manufacturing of superstructures with length scales well beyond that of the MOF pore size,layer-by-layer(Ibl)methods are particularly attractive.These allow the isoreticular approach to be extended to superstructures with micrometer length scales,a range that is not accessible using conventional MOF design.The Ibl approach further substantially extends the compositional diversity in MOFs.At the same time,the favorable elastic properties of MOFs allow for heteroepitaxial growth,even in the case of lattice misfits as large as 20%.While the MOF-on-MOF approach to designing multicomponent superstructures with synergistic multifunctionality can also be realized with sophisticated solvothermal synthesis schemes,the Ibl(or liquid-phase epitaxy)approach carries substantial advantages,in particular when it comes to the integration of such MOF superstructures into optical or electronic devices.While the structure vertical to the substrate can be adjusted using the Ibl method,photolithographic methods can be used for lateral structuring.In this review,we will discuss the Ibl liquid-phase epitaxy approach to growing surface-anchored MOF thins films(SURMOFs)as well as other relevant one-pot synthesis methods for constructing such hierarchically designed structures and their emerging applications. 展开更多
关键词 metal-organic framework(MOF)heterostaicture hierarchical assembly EPITAXY layer-by-layer growth surface-anchored MOFs
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Energy Absorption in Functionally Graded Concrete Bioinspired by Sea Urchin Spines 被引量:2
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作者 Nicu Toader Werner Sobek Klaus G Nickel 《Journal of Bionic Engineering》 SCIE EI CSCD 2017年第2期369-378,共10页
Functionally Graded Concrete (FGC) is fabricated at the Institute for Lightweight Structures and Conceptual Design (ILEK) by using a layer-by-layer technique with two different technological procedures: casting a... Functionally Graded Concrete (FGC) is fabricated at the Institute for Lightweight Structures and Conceptual Design (ILEK) by using a layer-by-layer technique with two different technological procedures: casting and dry spraying. Functional gradations are developed from two reference mixtures with diametrically opposed characteristics in terms of density, porosity, compression strength and elasticity modulus. In this study the first mixture consists of Normal Density Concrete (NDC), with density about 2160 kg·m^-3 while the second mixture helps to obtain a very lightweight concrete, with density about 830 kg·m^-3. The FGC specimens have layers with different alternating porosities and provide superior deformability capacity under bulk compression compared to NDC specimens. In addition, the FGC specimens experienced a graceful failure behaviour, absorbing high amounts of energy during extended compression paths. The porosity variation inside the layout of tested specimens is inspired by the internal structure of sea urchin spines of heterocentrotus mammillatus, a promising role model for energy absorption in biomimetic engineering. 展开更多
关键词 biomimetic engineering energy absorption sea urchin spine functionally graded concrete graceful failure behaviour
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Surface-Oriented Assembly of Cyclodextrin Metal-Organic Framework Film for Enhanced Peptide-Enantiomers Sensing
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作者 Li-Mei Chang Qiao-hong Li +3 位作者 Peter Weidler Zhi-Gang Gu Christof Wöll Jian Zhang 《CCS Chemistry》 CAS 2022年第11期3472-3481,共10页
Oriented metal-organic framework(MOF)films are attracting great attention due to their fascinating physicochemical properties and unique functionalities.Here,we report an[110]-oriented biomolecularγ-cyclodextrin(γCD... Oriented metal-organic framework(MOF)films are attracting great attention due to their fascinating physicochemical properties and unique functionalities.Here,we report an[110]-oriented biomolecularγ-cyclodextrin(γCD)MOF film with arrayed CD channels running perpendicular to the substrate surface.This sophisticated architecturewas realized by combining liquid phase epitaxial layer-by-layer(lbl)methods with aγCD-based thiol self-assembled monolayer(SAM)functionalized surface.This first demonstration of the lbl method for MOF growth from aqueous conditions yielded oriented,highly homogeneous,and chiralγCD-SURMOFs(surfacecoordinated MOFs)with tunable thickness.Using a quartz crystal microbalance(QCM)to monitor adsorption of biomolecules,we demonstrated thatγCD-SURMOF provides highly-efficient recognition of tripeptide enantiomers(Tyr-(L-Ala)-Phe vs Tyr-(D-Ala)-Phe),clearly outperformingγCD(SH)_(8) SAMs as well as polycrystalline,mixed-orientationsγCDMOF film.The presence of well-alignedγCD-channels enables highly efficient transport channels with large adsorption capacity and fast loading,along with high enantioselectivity.In addition,the fast and highly specific loading rates allow for the realization of highly specific sensors for biomolecules with short response times. 展开更多
关键词 metal-organic frameworks oriented assembly thin film CYCLODEXTRIN chiral sensing
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旭辉超高标德系精工研发项目
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作者 Peter lppolito Highlight Image(Spencer Huang) 《现代装饰》 2019年第9期74-81,共8页
随着时代的更新和现代人对精神层面的不断追求,未来的居住方式也成为了我们值得讨论的话题。具有艺术格调的旭辉上海超高标户型室内设计项目通过对未来生活的解读,从材料、色彩、形状三方面叠加组合,增添丰富的层次感和探索的趣味性,表... 随着时代的更新和现代人对精神层面的不断追求,未来的居住方式也成为了我们值得讨论的话题。具有艺术格调的旭辉上海超高标户型室内设计项目通过对未来生活的解读,从材料、色彩、形状三方面叠加组合,增添丰富的层次感和探索的趣味性,表达高品质的生活态度,让生活在此的住客享受愉快舒适的城市生活。 展开更多
关键词 渐变镜 研发项目
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