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银纳米颗粒-玻璃复合材料的光学性能 总被引:2,自引:1,他引:1
采用离子交换结合热处理法,制备出银纳米颗粒-硅酸盐玻璃复合材料.利用紫外-可见光 分光光度计测量吸收光谱,利用Z-scan技术测量三阶非线性光学效应.研究结果表明,离子交换的最佳温度范围为310℃-380℃,提高离子交换温度和熔盐中AgNO3浓度,延长离子交换时间,有利于在玻璃中引入更多的银离子.玻璃中引入的银离子浓度越高,高温热处理后玻璃中银纳米颗粒的体积分数越大.含铁玻璃有利于银纳米颗粒的形成.随着热处理温度的提高和时间的延长,银纳米颗粒尺寸和颗粒体积分数增大,共振吸收峰红移.通过离子交换结合热处理方法可以获得具有优良三阶非线性光学性能的银纳米颗粒-硅酸盐玻璃复合材料,其在非等离子体共振区域的三阶非线性系数可达1.16×10-10esu,其中实部为-1.15×10-10esu,虚部为1.4×10-11esu. 相似文献
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AgCl纳米晶掺杂铌碲酸盐系统非线性光学玻璃材料研究 总被引:4,自引:0,他引:4
铌碲酸盐非线性光学玻璃具有优良的三阶非线性光学效应,引入适量纳米晶体后,有望进一步提高玻璃的三阶非线性光学性能.本文采用在辅助电场诱导下的热处理方法在TeO2-Nb2O5-BaO-AgCl系统玻璃中析出AgCl纳米晶体,并研究了AgCl含量、热处理工艺及电场施加工艺对纳米晶析出和三阶非线性光学性能的影响.结果发现,在铌碲酸盐系统玻璃中引入0.1%~0.35%(质量分数)的AgCl,经热处理后可在玻璃中获得AgCl纳米晶体,而辅助电场提供的较小推动力可诱导更多的纳米晶体均匀析出,并且可以将其尺寸控制在20nm以下.采用辅助电场与热处理工艺相匹配的控制技术可以明显提高材料的三阶非线性光学性能. 相似文献
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非线性光学材料在图像处理、全光开关、光学存储和记忆系统等领域有着较大的应用潜力,近年来对三阶非线性光学聚合物材料的研究成为研究工作中的热点.分类介绍了各种有机三阶非线性光学聚合物的合成、结构与性能的最新研究进展,评述了三阶非线性光学性能表征技术的研究状况,展望了有机三阶非线性光学材料的前景和存在的问题. 相似文献
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为了提高聚吡咯(PPy)的光电性能,通过界面聚合-原位法制备了PPy/Cd S复合薄膜材料,用红外光谱、X射线衍射、扫描电镜、热重分析等方法对产物进行了表征。制备的PPy/Cd S薄膜结构平整,投料比对Cd S纳米棒尺度有明显影响。用紫外吸收、Z-扫描技术初步研究了PPy/Cd S的非线性光学(NLO)性质。PPy/Cd S具有明显的饱和吸收和非线性负折射。PPy/Cd S(摩尔比10∶1)薄膜的非线性折射率是PPy薄膜的2.4倍,三阶非线性极化率是PPy的2.1倍,说明PPy/Cd S薄膜具有良好的三阶NLO性能。该复合材料在光限幅等光电领域具有潜在的应用价值。 相似文献
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寻找具有增强的非线性光学响应的材料一直是国际学术界的热点问题之一.本文研究了巨电流变液的非线性光学响应.我们发现,当巨电流变液中的纳米颗粒添加一层具有内秉非线性光学响应的涂层时,体系的有效非线性光学响应可以得到极大增强.所以,巨电流变液有望成为一种新型的非线性光学材料. 相似文献
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《International journal for numerical methods in engineering》2018,113(9):1488-1506
In this paper, we present a new method for inserting several triangulated surfaces into an existing tetrahedral mesh generated by the meccano method. The result is a conformal mesh where each inserted surface is approximated by a set of faces of the final tetrahedral mesh. First, the tetrahedral mesh is refined around the inserted surfaces to capture their geometric features. Second, each immersed surface is approximated by a set of faces from the tetrahedral mesh. Third, following a novel approach, the nodes of the approximated surfaces are mapped to the corresponding immersed surface. Fourth, we untangle and smooth the mesh by optimizing a regularized shape distortion measure for tetrahedral elements in which we move all the nodes of the mesh, restricting the movement of the edge and surface nodes along the corresponding entity they belong to. The refining process allows approximating the immersed surface for any initial meccano tetrahedral mesh. Moreover, the proposed projection method avoids computational expensive geometric projections. Finally, the applied simultaneous untangling and smoothing process delivers a high‐quality mesh and ensures that the immersed surfaces are interpolated. Several examples are presented to assess the properties of the proposed method. 相似文献
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Standards are the basis for production enterprises to organize production ex-factory inspection trade 《中国标准化(英文版)》2008,25(1):24-25
Standards are the basis for production enterprises to organize production, ex-factory inspection, trade (delivery) and technical exchanges, product certification, quality arbitration and supervision.…… 相似文献
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A flow calorimeter for enthalpy increment measurements on condensed gases is presented. A better knowledge of the properties of the liquefied natural gas is needed, and therefore a liquid loop has been designed for our flow calorimeter. The fluid loop in the calorimeter is designed in order to avoid the two-phase region, since two phases would give compositional disturbances in the measurements. The avoidance of the two-phase region is made possible by increasing the pressure of the test fluid after the measurement section, then heating the fluid at super-critical pressure past the critical point. Finally, the fluid is throttled to the low-pressure gas state at the inlet condition of the compressor that circulates the fluid. To perform the pressure increase, a new cryogenic pump has been designed. To evaluate the new equipment, measurements were taken on liquid ethane over the temperature range 146–256 K at pressure between 0.9 and 5.1 MPa. 相似文献
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On November 30, 2007, the China Association for Standardization (CAS) held a press conference at Beijing Diaoyutai State Guest House. Leaders from the China Household Electric Appliance Research Institute, the China Household Electric Appliance Association, and the China Consumers' Association attended and made speeches.…… 相似文献
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Zusammenfassung Bei der Gestaltung von Ernteprozessen — beispielsweise des Prozesses Mähdrusch, Körnertransport und -abnahme — als transportverbundene Fließarbeitsverfahren mit mindestens zwei verschiedenen Arbeitsmitteln gibt es einen großen Optimierungsspielraum. Solche Prozesse sind mehrstufige Bedienungsprozesse mit gemischter Anordnung der Bedienungseinrichtungen. Außerdem besitzen sie stark ausgeprägte räumliche Aspekte. Es wird vor allem gezeigt, welche Merkmale solcher Prozesse in Simulationsmodellen abgebildet sein müssen, welche Zielgrößen in Abhängigkeit von welchen Einflußgrößen unter Berücksichtigung welcher Prozeßbedingungen ermittelt werden sollten und wie der Bewertungsprozeß zur Ermittlung der gewünschten Informationen gestaltet werden muß. 相似文献
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C. Qihong W. Zhan‐Wen J. Yi J. Yehua L. Fei F. Hanguang 《Materialwissenschaft und Werkstofftechnik》2014,45(7):582-590
In the present study a high‐boron high speed steel (HSS) roll material was designed. Many expensive alloy elements have been substituted by cheap boron alloy, and high‐boron high speed steel roll has been manufactured by centrifugal casting method. The microstructures, mechanical properties and wear resistance of centrifugal casting high‐boron high speed steel roll have been investigated by optical microscopy (OM), scanning electron microscopy (SEM), and X‐ray diffraction (XRD) analysis, hardness test, impact test and wear test. The results indicated that the solidification microstructures of high‐boron high speed steel roll consisted of M2(B,C), (W,Mo)2(B,C), M3(B,C), M23(B,C)6 type borocarbides and martensite, a small amount of retained austenite. Borocarbides were continuously distributed over the grain boundary. After quenching from 1050 °C, local broken network appeared in partial borocarbides, and fine secondary borocarbide precipitated from the matrix. After tempering from 525 °C, the amount of precipitated borocarbide increased significantly. After heat treatment, the hardness of high‐boron high speed steel roll excelled 60 HRC, and its impact toughness excelled 8.0 J/cm2. The single groove steel rolling amount of high‐boron high speed steel rolls increases by 500% than that of bainite cast iron roll, when the rolls are used in K1 mill housing of bar mill. 相似文献
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Dimiter Hadjistamov 《材料科学与工程:中英文B版...》2019,(2):56-65
The definition of the thixotropy is a decrease in viscosity with time in shear and a subsequent recovery of viscosity after the shear deformation is removed.We ... 相似文献
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《中国标准化(英文版)》2014,(4)
正Responding to ISO’s appeal for survey for the to-be-developed ISO Strategy Plan for 2016-2020,SAC hosted a special workshop over the needs and comments of various fi elds on June 8 in Beijing.The workshop was attended by ISO President-elect and Ansteel General Manager Zhang Xiaogang,SAC Vice-Administrator Yu Xinli,and 30 experts from 相似文献
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《中国标准化(英文版)》2014,(5)
正The review group of Asia Pacific Laboratory Accreditation Cooperation(APLAC)carried out a 4-day peer review of the proficiency testing provider(PTP)for China National Accreditation Service for Conformity Assessment(CNAS)from July 28 to 31,2014.CNAS passed the PTP review with excellent performance.Two senior peer reviewers of APLAC made a comprehensive,rigorous and detailed review of CNAS’s PTP accreditation activities,and made the on-spot inspection of the review groups in Shanghai and Shenzhen respectively. 相似文献