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基于卤钨灯和LED的复合光源设计与实现 被引量:6
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作者 隋成华 杜春年 徐丹阳 《浙江工业大学学报》 CAS 北大核心 2017年第3期351-354,共4页
在光谱检测技术中所采用的光谱范围通常在紫外-可见光波段,同时要求该光源能够输出连续、稳定且光强较强的光,一般的单一光源很难满足这个要求.通常卤钨灯在可见光波段能很好的满足光谱检测分析,但在紫外波段无法满足要求.鉴于此,紫外LE... 在光谱检测技术中所采用的光谱范围通常在紫外-可见光波段,同时要求该光源能够输出连续、稳定且光强较强的光,一般的单一光源很难满足这个要求.通常卤钨灯在可见光波段能很好的满足光谱检测分析,但在紫外波段无法满足要求.鉴于此,紫外LED灯可以弥补卤钨灯在紫外波段光强较弱的缺陷.为了实现紫外-可见光-近红外复合光源的设计,采用恒压输出驱动不同功率紫外LED灯,实现光谱光强的均匀性,最终设计成功一款小型紫外-可见光-近红外复合光源. 展开更多
关键词 卤钨灯 LED 复合光源 光谱测量
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杉木组培苗生根质量优化研究
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作者 蒋凡 买凯乐 《湖北农业科学》 2020年第11期81-83,88,共4页
从两个方面优化杉木[Cunninghamia lanceolata(Lamb.)Hook.]组培苗生根质量,一是在增殖阶段对其进行高浓度和低浓度激素培养基交替处理以优化组培芽苗的质量,从而达到优化杉木组培苗生根质量;二是在生根阶段改变光源,以优化杉木组培苗... 从两个方面优化杉木[Cunninghamia lanceolata(Lamb.)Hook.]组培苗生根质量,一是在增殖阶段对其进行高浓度和低浓度激素培养基交替处理以优化组培芽苗的质量,从而达到优化杉木组培苗生根质量;二是在生根阶段改变光源,以优化杉木组培苗生根质量。结果表明,高浓度激素和低浓度激素交替处理后的杉木增殖芽苗,具有增殖率高、生长快、节间距适中、木质化程度较高等表观性状,且这些性状随着继代次数的增加表现比较稳定,增殖芽接种到生根培养基后,生根率最高达到86.5%,生根数量最高达到2.7条。LED复合光源红蓝光配比为2∶1时生根率最高,达到86.7%;在红蓝光配比为4∶1时生根数量最高,达到2.8条。 展开更多
关键词 杉木[Cunninghamia lanceolata(Lamb.)Hook.] 组培苗 激素 LED复合光源
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Numerical simulation and experimental study of hybrid laser-electric arc welding between dissimilar Mg alloys 被引量:3
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作者 MA Yu-lin ZHU Jian +7 位作者 ZHANG Long-mei REN Zhi-qiang ZHAO Yang WANG Wen-yu WANG Xiao-ming HUI Xi-dong WU Yong-ling ZHENG Hong-yu 《Journal of Central South University》 SCIE EI CAS CSCD 2022年第10期3476-3488,共13页
This work aims to establish a suitable numerical simulation model for hybrid laser-electric arc heat source welding of dissimilar Mg alloys between AZ31 and AZ80. Based on the energy conservation law and Fourier’s la... This work aims to establish a suitable numerical simulation model for hybrid laser-electric arc heat source welding of dissimilar Mg alloys between AZ31 and AZ80. Based on the energy conservation law and Fourier’s law of heat conduction, the differential equations of the three-dimensional temperature field for nonlinear transient heat conduction are built. According to the analysis of nonlinear transient heat transfer, the equations representing initial conditions and boundary conditions are obtained. The “double ellipsoidal heat source + 3D Gaussian heat source”combination was chosen to construct the laser-electric arc hybrid heat source. The weld bead morphologies and the distribution of temperature, stress, displacement and plastic strains are numerically simulated. The actual welding experiments were performed by a hybrid laser-electric arc welding machine. The interaction mechanism between laser and electric arc in the hybrid welding of Mg alloys is discussed in detail. The hybrid heat source can promote the absorption of laser energy and electric arc in the molten pool, resulting in more uniform energy distribution in the molten pool and the corresponding improvement of welding parameters. This work can provide theoretical guidance and data supports for the optimization of the hybrid laser-electric arc welding processes for Mg alloys. 展开更多
关键词 hybrid laser-electric arc welding dissimilar Mg alloys welding numerical simulation interaction mechanisms welding optimizations
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