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合成了一种新型三取代结构的双光子吸收材料1,3,5-三[4-[2-(3-吡啶)乙烯基]苯基]苯(4),通过元素分析、电喷雾质谱、1HNMR和红外对其进行表征。测试了紫外吸收光谱、单光子荧光光谱和双光子荧光光谱,并测出其双光子吸收截面为7.63×10-48cm4.s.photon-1。利用合成的1,3,5-三[4-[2-(3-吡啶)乙烯基]苯基]苯作引发剂,以甲基丙烯酸甲酯齐聚物作单体(CN120C80),200fs,76MHz、Ti∶sapphire飞秒激光器作光源,进行了三维周期微结构的制作。所合成化合物是潜在应用前景的双光子吸收材料。 相似文献
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合成了一种新型三取代结构的双光子聚合引发剂1,3,5-三[4-(N,N-二乙氨基)苯基]乙烯基]苯基]苯(4),通过元素分析、电喷雾质谱、1 H NMR和红外谱对其进行表征。测试了紫外吸收光谱、单光子荧光光谱和双光子荧光光谱,并测出其双光子吸收截面为9.87×10-48cm4.s/photon。利用合成的1,3,5-三[4-(N,N-二乙氨基)苯基]乙烯基]苯基]苯作双光子聚合引发剂,以甲基丙烯酸甲酯齐聚物作单体(CN120C80),200fs,76MHz、Ti:sapphire飞秒激光器作光源,进行了三维周期微结构的制作。所合成化合物是潜在应用前景的双光子吸收材料。 相似文献
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用800nm波长的飞秒Ti:sapphire激光测定了2个对称型噁二唑衍生物2,5-二[4-(2-N,N-二苯氨基苯乙烯基)苯基]-1,3,4-噁二唑(PASPO)与2,5-二[4-{2-N,N-二(4-溴代苯)氨基苯乙烯基]苯基}-1,3,4-噁二唑(BrPASPO)的双光子吸收和双光子激发荧光光谱,其飞秒双光子吸收截面为20.6和9.91GM,双光子泵浦上转换荧光最大波长分别在535和545nm.测定了紫外吸收、荧光光谱,研究了化合物在不同溶剂中的溶致变色效应.化合物PASPO和Br-PASPO在二氯甲烷溶液中的吸收峰分别位于412和403nm,荧光发射峰分别位于511和495nm,荧光量子产率分别为0.73和0.70. 相似文献
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合成了一种新型三取代结构的双光子吸收材料1,3,5-三[4-[2-(噻吩)乙烯基]苯基]苯,通过元素分析、1 H NMR和红外光谱对其进行表征。测试了材料的紫外吸收光谱、单光子荧光光谱和双光子荧光光谱,并测出其双光子吸收截面为426×10-50cm4·s·photon-1。以1,3,5-三[4-[2-(噻吩)乙烯基]苯基]苯为引发剂,甲基丙烯酸甲酯齐聚物(CN120C80)为单体,飞秒激光器(200fs、76 MHz、Ti∶sapphire)为发光源,进行了三维周期微结构的制作。 相似文献
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聚3-己基噻吩的光电性能研究 总被引:4,自引:0,他引:4
利用光电化学方法研究了聚3-己基噻吩的光电化学性质,其禁带宽度为1.89eV,同时确定了它的价带位置(-3.6eV)、导带位置(-5.4eV).研究发现聚3-己基噻吩属于直接跃迁型半导体,在本文条件下得到的最高IPCE值达5.2% 相似文献
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采用微波辐射加热的方法,以亚碲酸钠(Na2TeO3)作碲源,以谷胱甘肽(GSH)作稳定剂,在水相中合成出高质量的CdTe量子点。所合成量子点的发射波长从515~630nm可调,荧光量子产率(PLQYs)最高达95%。利用X射线粉末衍射(XRD)、高分辨透射电镜(HRTEM)、紫外-可见吸收光谱(UV-Vis)和荧光发射光谱(PL)等技术表征产物的物相结构和光学性质。用双光子激发荧光法研究CdTe量子点的双光子吸收性质。用双光子激发荧光成像技术,以发红光的CdTe量子点作为双光子荧光探针成功标记了人肺腺癌细胞(A549)。 相似文献
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Permeable crystalline materialcan permeate into pores and cracks of concrete and catalyze the reaction between Ca(OH) 2and unhydrated cement to generate a great quantity needle non-soluble crystals, which can stop up the pores and cracks of concrete, and increase the impermeability of concrete. This paper reported the results of a study conducted to evaluate steel reinforcement corrosion of concrete specimens uncoated and coated with permeable crystalline material as well as mixed with the permeable crystalline material. The properties evaluated for corrosion test were water impermeability, water absorption, compressive strength and potential. The results of water impermeability, water absorption, compressive strength clearly showed that the permeable crystalline material could prohibit water, any soluble salts and moisture from penetrating the concrete to cause corrosion, leaking, and other problems, and it did increase the compressive strength, which was favorable for protection of corrosion of reinforcing steel. Moreover, it was concluded from the potential-time curve that the steel reinforcement of uncoated specimen was in the state of activation whereas that of other specimens coated and mixed with the permeable crystalline material was in the state of inactivation. Above all, it was indicated that the permeable crystalline materialis very effective to protect the steel reinforcement of concrete from corrosion. 相似文献
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In this paper, the principle of spurting take off lacquer were introduced; and with orthogonal method the unsaturate polyester was prepared ;it was easy to peel airplane paint layer off with this material and equipment. 相似文献
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Sandwich panels utilizing honeycomb cores result in lightweight, high-strength units that are very rigid. Indeed, they give honeycomb panels the best strength-to-weight ratio of any construction type available. Conventionally, the wax is poured into the cell of the core to strengthen the structure and prevent the core from being crushed during milling. Much time and labor is required to wax, mill, and clean the cores. In this study, the process of pouring wax into the core was skipped. In other words, the cutter directly milled the core. Experiments showed that the compressive strength of the core produced without wax stabilization was only 3% lower than that of cores produced using the traditional method. In addition, the drum peel strengths of cores produced without wax stabilization were 38.4% higher than cores produced using the traditional method, in which residual wax seriously polluted the adhesive. It was also found that eliminating the wax process can reduce costs. 相似文献
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Muhammad Harris Johan Potgieter Richard Archer 《Materials and Manufacturing Processes》2019,34(6):701-713
Polylactic acid (PLA) is one of the most widely used open source fused filament fabrication materials due to its ease of extrusion, biodegradability, and mechanical strength. The mechanical strength of PLA largely depends on the proper growth of its semi-crystalline structure, which can be severely impaired by a low rate of crystallization, particularly in open source printers. This can be further aggravated by the non-uniform thermal distribution of heat that causes improper curing among the extruded beads of the printing material. As a result, PLA printed on open source printers does not achieve the best mechanical properties. This research, for the first time, proposes an additive-free solution implemented through a detailed set of experimentation to improve the curing rate through in-process temperature variations to cure the joints among the beads. Scanning electron microscopy (SEM), differential scanning calorimetry (DSC) and Fourier transform infrared (FTIR) spectroscopy is used to confirm the improvements in the bead joints. This work is conducted in two phases of experiments. In the first phase, a full factorial ANOVA is used to investigate various process parameters and the important variables are used in the second phase to print test specimens in four different sets. 相似文献
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In continuous hot-dip galvanization process the corrosion and chemical stability of the sink roll in the galvanizing bath are important problem which effects on the quality and productivity. In order to protect the sink roll the carbide cermet and/or ceramic coatings were deposited on the surface of the sink roll. The WC-, Cr3 C2-cermet coatings were deposited by high velocity oxygen fuel (HVOF) spray, respectively. The coating samples were immersed in molten Zn-alloy containing 50 wt % aluminum at 833 K for 24 hr and 144 hr, respectively. The inter-diffusion and inter-reaction of Zn, Al and elements in coating and corrosion behaviors of these coatings were investigated by XRD, SEM and EPMA etc. The corrosion mechanisms of the carbide cermet coatings and ceramic coatings in molten High Al-Zn-alloy were approached. 相似文献
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Koji Matsumoto Michitaka Morohoshi Yoshikazu Teraoka 《International Journal of Refrigeration》2009,32(6):1336-1342
In many situations, ice often adheres to a cooling solid surface, frequently causing serious accidents. It is critical to clarify the mechanism of ice adhesion to the cooling surface in order to prevent ice adhesion. In a past study, the shearing stresses of two kinds of test plates with a copper surface having the higher thermal conductivity were measured. The shearing stress corresponds to ice adhesion force. Both shearing stresses were significantly different; however, the cause remains unclear.Therefore, the present study focuses on an oxide layer as the main factor causing the difference of both shearing stresses; the influence of the oxide layer formed on shearing stress was discussed. And in the removal and reformation processes of the oxide layer, the time variation of the shearing stress was clarified. Moreover, the relationship between the state of the copper surface and the shearing stress was also clarified by surface analysis. 相似文献
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郎志正 《中国标准化(英文版)》2014,(6):86-88
During his inspection in Henan Province in May, Chinese President Xi Jinping stressed to "push forward the transformation from China Speed to China Quality, from Made in China to Created in China, and from Chinese Products to Chinese Brand". The "Three Transformations" are the specific requirements and goal of China's national development in the context that market should play a decisive role in the allocation of resources. 相似文献
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正When you are enjoying the green,energy-saving and healthy lighting of IKEA LED luminaire,you may not realize that most of IKEA’s LED bulbs are produced by the LED luminaire smart manufacturing system of Hangzhou Zhongwei Photoelectricity CO.,LTD(ZVISION).No longer enclosed in the laboratory,the product standards are brought into the factory workshop and even to the entire production process.Thus,the standards are promoted and applied in a favorable way by enterprises,benefitting consumers with high quality products. 相似文献
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《中国标准化(英文版)》2014,(5):4-4
正The international standard,ISO 8124-6,Safety of toys–Part 6:Certain phthalate esters in toys and children’s products,was officially issued by ISO worldwide on August 15.It was the first time for Chinese experts to lead the ISO standard development in toys industry.The standard was drafted by a group of Chinese experts from SAC/TC for toys and relevant Chinese departments and finally completed by a dedicated international group of experts.ISO 8124-6 makes a substantive breakthrough in the aspects of the scope of toys,limitation of plasticizer types,control of test cost,accuracy of test,operation convenience,etc.,offering the operational guidance for toy manufactures and testing laboratories. 相似文献
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《中国标准化(英文版)》2014,(5):6-6
正SAC Administrator Tian Shihong led the Chinese delegation to visit the Spanish Association for Standardization and Certification(AENOR)on September 15,2014.Mrs.Begona Cristeto,the Vice-Minister of Industry,Energy and Tourism of Spain,and Mr.Avelino Brito,the President and CEO of AENOR greeted the delegation.The two sides had a deep and friendly discussion on strengthening the cooperation between China and Spain in the standardization field and promoting the standardization work to support the development of economy and trade in the two countries. 相似文献