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抗红外/激光双模烟幕干扰材料的研究 总被引:1,自引:0,他引:1
本文以SiO2、CaCO3、MgO、TiO2等为原料,利用高温烧制的方法,制备出了能够遮蔽8~14μm波长红外光和10.6μm、1.06μm波长激光的烟幕干扰材料.研究结果表明,当该烟幕干扰材料的平均粒径d50为4.2μm时,具有很好的遮蔽效果,对8~14μm波长红外光和10.6μm激光遮蔽率≥85%(透过率≤15%),对1.06μm波长激光遮蔽率≥80%(透过率≤20%),同时又具有较长的持续遮蔽时间. 相似文献
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全息激光防护薄膜的研制 总被引:2,自引:0,他引:2
介绍了全息激光防护薄膜基本理论和设计方法。研制成功的全息激光防护薄膜,其光学性能测试表明:0.53μm波长激光的光密度D达4.11,防护角达15°,具有良好的可见光透过率,且抗激光破坏能力强,可用于人眼和光电探测系统的激光防护。 相似文献
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分析了SmBO3颗粒度对粉体散射作用和吸收作用的影响.激光防护功能填料对激光的散射作用主要考虑米氏散射;在激光防护功能填料质量一定的条件下,粒径越小,粒子数就越多,粒子对光的吸收截面越大,吸收系数也就越大.对于SmBO3激光防护功能填料,折射率n=1.95时,激光波长为1.06μm,散射面积比Q(γ)随粒径参数γ的函数变化关系图可以得到当X=1.771时,SmBO3的散射面积比最大,此时27πλ=1.771.即r≈298nm.所以当颗粒尺寸大约在600nm左右时,SmBO3微粒的散射消光作用最强.在1.05~1.15μm波长范围内,随着SmBO3颗粒的长大,粉体对1.06μm波长处的光的反射率有所降低,并在颗粒大小为587nm左右时达到最低值,约为0.5%.而当颗粒尺寸进一步长大时,SmBO3粉体对1.06μm波长处的光的反射率值又有所提高.当颗粒大小达到1μm左右时,SmBO3粉体对1.06μm波长处的光的反射率约0.6%.这与理论计算得出的具有最佳散射消光的SmBO3粉末的颗粒尺寸为600nm左右相一致,符合理论计算结果.激光测试也显示600nm左右的SmBO3颗粒对1.06μm激光的反射率最低,符合理论计算结果. 相似文献
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多波段兼容隐身功能填料的制备及其性能研究 总被引:5,自引:0,他引:5
采用共沉淀法制得了Cr2O3包覆片状铝粉的Al/Cr2O3复合粒子。借助XRD、IR、SEM以及激光粒度仪对Al/Cr2O3粉末的相组成、形貌和粒径分布进行了表征。此外,测试了Al/Cr2O3粉末的红外辐射率和1.06μm波长处的反射率性能。结果表明,实验制得的Al/Cr2O3复合粒子厚度基本均匀,平均粒径较原始铝粉有所增加;红外辐射率为0.66,属于中低红外辐射率;1.06μm波长处的反射率为0.41%,激光吸收性能强。同时,复合粒子本身的绿色还可以起到可见光隐身的效果。 相似文献
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玻璃表面由于反射作用会使光能损失.为了减少玻璃表面的反射损失,可以通过在表面镀增透膜来解决.研究了多层增透膜对铒硼硅酸盐玻璃可见光透过率的影响.在理论上比较了不同膜系结构(层数不同)的增透膜对铒硼硅酸盐玻璃的增透效果.采用了六层膜的设计,并对镀膜前后玻璃的反射率和透过率进行了测试,玻璃在可见光区的430nm波段到800m波段的平均反射率从原来的7.5%左右下降到了1%左右,其吸收光谱曲线的最高透过率从未镀膜前的80%左右提高到了97%左右.同时,镀膜后的铒硼硅酸盐玻璃在0.53μm处的透过率仍然保持在0.01%(光密度D0.53=4),而可见光透过率达到了65%,比镀膜前提高了10%左右,玻璃的可视性得到了明显的改善. 相似文献
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一种用于自然辐射冷却的光谱选择性透过薄膜 总被引:1,自引:0,他引:1
本文介绍了溶胶-凝胶法制备光谱选择性透过薄膜,通过对样品的光谱透过率的测试,分析和研究这些样品薄膜的性能,结果表明:掺杂碳黑浓度为0.12%,厚度约为0.3μm的二氧化钛薄膜样品的光谱透过性能较优,其在8-12μm波段的透过率超过80%,在可见光波段内的透过率低于15%,作为自然辐射冷却应用的选择性透过覆盖材料,它具有阻挡太阳光中可见光加热其下的物体,同时又允许物体的热以辐射方式穿透该薄膜散发到大 相似文献
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《功能材料》2015,(19)
使用染料-高聚物混(dye-polymer)的方法将光吸收染料UV360、VIS532、NIR1064作为功能添加剂分散在聚碳酸酯(PC)中,采用注射成型的方法制备了一种防紫外、防眩光、防980和1 064nm激光波长的多波段吸收PC滤光镜片。研究了光吸收染料在聚碳酸酯中的吸收特性,确定了光吸收染料的添加量,最终制备的PC镜片在250~400nm紫外波段的透过率为0.06%,在400~700nm可见光波段的透过率为14.43%,在980和1 064nm激光波长处的透过率为0.006%和0.003%(吸光度4)。镜片材料的冲击强度为60.4kJ/m2,弯曲强度为120 MPa,力学性能优良。在经过高温、低温和光照环境实验后,镜片的光学性能未发生明显变化,具有良好的应用性能。 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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《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
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《中国标准化(英文版)》2014,(4)
正China and Greece Sign the Standardization Cooperation Agreement Witnessed by Chinese Premier Li Keqiang and Greek Prime Minister Antonis Samaras,AQSIQ Minister Zhi Shuping and ELOT Chairman and Executive Director Angelos Tolkas signed the SAC-ELOT Standardization Cooperation Agreement.The Agreement is one of the critical cooperation documents signed during Li Keqiang’s visit in Greece,encouraging China and Greece to 相似文献