共查询到20条相似文献，搜索用时 250 毫秒
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《科技成果管理与研究》2016,(7)
在国家863计划近十年的持续支持下,特别是在"十二五"地球观测与导航技术领域863计划项目"星载红外高光谱成像载荷研制"的支持下,以王建宇研究员为代表的中国科学院上海技术物理研究所课题团队于2015年初研制成功热红外高光谱成像仪,成像仪的指标和国际先进设备相当,可为行业部门提供8.0~12.5μm高质量热红外光谱数据,对进一步开展红外高光谱应用研究具有重要意义. 相似文献
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利用一组非线性耦合方程,在理论上推导出了双泵浦、级联结构光纤参量放大器的增益表达式。研究表明,在双泵浦情况下,光纤参量放大器的增益与光纤长度、非线性系数以及泵浦光功率呈指数关系。采用多段光纤级联的结构,可以均衡光纤参量放大器增益的不平坦性,理论上得到了带宽达160nm、起伏小于1．5dB的理想增益。 相似文献
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随着高功率半导体激光器在科学研究,航空航天,激光显示,工业,表面处理,医疗应用等诸多领域的应用不断增加,高电光转换效率,高输出功率,体积小巧的半导体激光器,期望长寿命和高可靠性。半导体激光器堆栈的水平阵列广泛用于工业中泵浦固体激光器的应用。在连续操作中,五个激光棒的HA输出功率可以达到300W。激光装置的窄光谱和精确中心波长的光谱是泵浦应用中泵浦晶体的高吸收效率所需的。然而,由于焊接在散热器或冷却板上之前和之后的波长变化,多个半导体激光器叠层的光谱控制是困难的。通常光谱分布受半导体激光器的键合质量冷却板上的热分布,不同层的应力以及激光芯片性能等因素的影响。所有这些因素在焊接前难以预测和控制。在高功率半导体激光堆栈开发中,频谱的精确控制是至关重要的。 相似文献
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ASTER是搭载在Terra上的一种多光谱高分辨率遥感数据源,它包含从可见光到热红外范围的l4个波段,分辨率从15m到90m,具有多种用途,本文介绍了ASTER数据特性及其优缺点,并阐述了ASTER数据在内蒙古地区的应用前景。 相似文献
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高功率放大器效率一直以来是功放设计力求突破的方向之一。文章采用逆F类设计方法,深入分析了逆F类工作原理及设计重难点,给出了设计实物及测试结果。在平均功率输出30W情况下,效率较AB类功放提高8%。 相似文献
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Using femtosecond laser to fabricate highly precise interior three-dimensional microstructures in polymeric flow chip 总被引：1，自引：0，他引：1
This paper reports using femtosecond laser marker to fabricate the three-dimensional interior microstructures in one closed flow channel of plastic substrate. Strip-like slots in the dimensions of 800 μm×400 μm×65 μm were ablated with pulse Ti:sapphire laser at 800 nm (pulse duration of ～120 fs with 1 kHz repetition rate) on acrylic slide. After ablation, defocused beams were used to finish the surface of microstructures. Having finally polished with sonication, the laser fabricated structures are highly precise with the arithmetic roughness of 1.5 and 4.5 nm. Fabricating such highly precise microstructures cannot be accomplished with nanosecond laser marking or other mechanical drilling methods. In addition, since laser ablation can directly engrave interior microstructures in one closed chip, glue smearing problems to damage molded microstructures possibly to occur during the chip sealing procedures can be avoided too. 相似文献
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A size-selective cell sorting microfluidic device that utilizes optical force is developed. The device consists of a three-dimensional polydimethylsiloxane microstructure comprised of two crossed microchannels in a three-dimensional configuration. A line shaped focused laser beam is used for automatic size-selective cell sorting in a continuous flow environment. As yeast cells in an aqueous medium are fed continuously into a lower channel, the line shaped focused laser beam is applied (perpendicular to the direction of flow) at the junction of the two crossed channels. The scattering force of the laser beam was employed to push cells matching specific criteria upward from one channel to another. The force depends on the size of the cells, the laser power, and the fluid flow speed. The variation in size of yeast cells causes them to follow different routes at the intersection. For flow speeds below 30 μm∕s, all yeast cells larger than 3 μm were removed from the main stream. As a result, a high purity sample of small cells can be collected at the outlet of bottom channel. 相似文献
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鄱阳湖区近地层风能资源特征研究 总被引：2，自引：0，他引：2
在鄱阳湖区4座测风塔历时1年逐10分钟梯度观测的资料基础上,统计分析了该地区平均风特征和风能资源参数。.结果表明:鄱阳湖区风速随着高度升高而增加较为缓慢,风切变指数较平原地区明显偏小,在湖区北部的狭长地带,狭管效应对风速的增强作用较为明显;受地形的影响,鄱阳湖北部狭管内风廓线分布高度一致,狭管内外明显不同;鄱阳湖区地势低洼的地方湍流强度高于地势较高的地方的湍流强度,山脊处湍流强度随高度变化不明显,在狭管内,湍流强度较狭管外开阔湖面小;鄱阳湖区风场各高度层Weibull尺度因子值在4.92～7.49之间,各高度层Weibull形状参数值在1.49～1.84之间。观测塔位于山脊上的长岭的层形状参数和射山的尺度因子值随高度的变化趋势不同于另外两个测风塔。 相似文献
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The study investigates the use of CO2 laser to induce glass strip peeling off to form microchannels on soda lime gass substrate. The strip peeling exhibits a strong dependence on the energy deposition rate on the glass surface. In spite of the vast difference in the combination of laser power and scanning speed, when the ratio of the two makes the energy deposition rate in the range 3.0-6.0 J/(cm2 s), the temperature rising inside glass will be above the strain point and reach the softening region of the glass. As a result, glass strip peeling is able to occur and form microchannels with dimensions of 20-40 μm in depth and 200-280 μm in width on the glass surface. Beyond this range, higher energy depsotion rate would lead to surface melting associated with solidification cracks and lower energy deposition rate causes the generation of fragment cracks. 相似文献
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We developed an automated laser induced fluorescence system utilizing microfluidic chips for detection and quantification of immunoglobulins. Microchips were fabricated from polydimethysiloxane (PDMS) using the so-called "prepolymerization technique." The microchip structure helped minimize the effects of PDMS autofluorescence and light scattering. Furthermore, a thin and uniform PDMS layer forming the top of the microchip enabled proper focusing and collection of the excitation beam and the emitted fluorescence, respectively. The developed system was tested for the detection of mouse immunoglobulins. The capturing antibodies were immobilized on internal microchannel walls in the form of a polyelectrolyte. We clearly show that this immobilization technique, if correctly realized, gives results with high reproducibility. After sample incubation and washing, secondary antibodies labeled by fluorescein isothiocyanate were introduced into microchannels to build a detectable complex. We show that mouse antibodies can be quantified in a wide concentration range, 0.01-100 μg ml(-1). The lower detection limit was below 0.001 μg ml(-1) (6.7 pM). The developed laser induced fluorescence (LIF) apparatus is relatively cheap and easy to construct. The total cost of the developed LIF detector is lower than a typical price of plate readers. If compared to classical ELISA (enzyme linked immunosorbent assay) plate systems, the detection of immunoglobulins or other proteins in the developed PDMS microfluidic device brings other important benefits such as reduced time demands (10 min incubation) and low reagent consumption (less than 1 μl). The cost of the developed PDMS chips is comparable with the price of commercial ELISA plates. The main troubleshooting related to the apparatus development is also discussed in order to help potential constructors. 相似文献
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目的：建立注射用维库溴铵有关物质的检测方法。方法：采用反相HPLC法,色谱柱为Agilent EclipseXD（BC-18,250×4.6mm,5μm）,流动相为：pH为6.5的18.0g·L^-1的四甲基氢氧化铵的溶液-甲醇-乙腈（50：250：700）,流速1.5ml·min-1,柱温40℃,进样量20μL,检测波长为210nm。稀释剂：乙腈：0.01mol·L^-1盐酸溶液（1：1）;结果：杂质A、杂质C和杂质E的检测限都为0.007%、杂质D和维库溴铵的检测限为0.006%,定量限为0.02%,柱温、流速、流动相比例经过微小变化不影响检测结果。结论：本方法灵敏度高,准确度高,可用于注射用维库溴铵有关物质的检测。 相似文献
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目的:建立测定盐酸克林霉素阴道泡腾片含量的方法。方法:使用高效液相色谱法,色谱柱为Diamonsil C18柱(250mm×4.6mm,5μm),检测波长214nm,0.025mol/L磷酸二氢铵溶液(以磷酸调节pH=2.9)-乙腈(60:40)为流动相。流速:1.0ml/min.。结果在60.0μg~480.0μg/mL范围内有良好的线性,平均回收率为93.78%,RSD为1.05%(n=6)。结论:该法操作简便,结果准确,灵敏度高,重现性好,可用于盐酸克林霉素阴道泡腾片的质量控制。 相似文献