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1 引言目前,许多研究都集中于研制各种用途的中波红外成像系统。这些应用从工业用热成像一直扩展到探测车辆、导弹等的军用热成像。可反映中波红外成像目前技术水平的是加工碲镉汞、锑化铟等半导体探测器的线阵或面阵,并把它们组装到一适当光学成像系统。但是,材料和器件的产额低,这种器件不仅制作难而且成本高。本文介绍一种加工成本低用于中波红外成像的新型探测介质,具体地讲,这种新介质是一种可将中波红外 相似文献
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Ammar R Ball RC Banerjee S Bhat PC Bosetti P Bromberg C Canough GE Coffin T Dershem TO Dixon RL Fenker HC Ganguli SN Gensch U Girtler P Goshaw AT Grard F Gurtu A Hamilton C Henri VP Hernandez JJ Hrubec J Iori M Jones LW Kuhn D Knauss D Leedom ID Legros P Lemonne J Leutz H Liu X Malhotra PK Marraffino JM Mendez GE Miller R Naumann T Nguyen A Nowak H Pilette P Poirier J Poppleton A Raghavan R Rasner K Reucroft S Robertson WJ Roe BP Roth A Senko M Struczinski W Subramanian A Touboul MC Vonck B 《Physical review letters》1988,61(19):2185-2188
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The feasibility of determining aqueous ozone by chemiluminescence flow-injection analysis (CL-FIA) was studied for applications in potable water treatment. The ozonated water sample is injected into a pure water carrier and mixed with a dye reagent in front of a photodetector. Many reagents undergo fast CL reactions with aqueous ozone. Most of these reactions display considerable selectivity for ozone over other oxidants of importance in water treatment. Even when there is steady-state response to another oxidant, significant discrimination against the interferents is possible by taking advantage of the much faster kinetics of the CL reaction with ozone. A simple design of a Siemens-type ozone generator and preparation of standard ozone solutions are also described. 相似文献
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Thiosalicylic acid (TSA)-modified Amberlite XAD-2 (AXAD-2) was synthesized by coupling TSA with the support matrix AXAD-2 through an azo spacer. The resulting chelating resin was characterized by elemental analyses, thermogravimetric analysis (TGA) and infrared spectra. The newly designed resin quantitatively sorbs CdII, CoII, CuII, FeIII, NiII and ZnII at pH 3.5-7.0 when the flow rate is maintained between 2 and 4 ml min-1. The HCl or HNO3 (2 mol l-1) instantaneously elutes all the metal ions. The sorption capacity is 197.5, 106.9, 214.0, 66.2, 309.9 and 47.4 mumol g-1 of the resin for cadmium, cobalt, copper, iron, nickel and zinc, respectively, whereas their preconcentration factor is between 180-400. The breakthrough volume of HCl or HNO3 for elution of these metal ions was found to be 4-8 ml. The limit of detection (LOD) for CdII, CoII, CuII, FeIII, NiII and ZnII was 0.48, 0.20, 4.05, 0.98, 1.28 and 3.94 micrograms l-1, respectively, and the limit of quantification (LOQ) was found to be 0.51, 0.29, 4.49, 1.43, 1.58 and 4.46 micrograms l-1, respectively. The loading half time, t1/2, for the cations was found to be less than 2.0 min, except for nickel for which the value was 13.1 min. The determination of each of these six cations is possible in the presence of other five, if their concentration is up to 4 times. All six metals were determined in river water (RSD approximately 0.7-7.7%) and tap water samples (RSD approximately 0.3-5.7%). The estimation of Co was made in the samples of multivitamin tablets (RSD < 2.3%). The results agree with those quoted by manufacturers. 相似文献
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Superheated water eluent capillary liquid chromatography 总被引:4,自引:0,他引:4
A capillary scale reverse phase liquid chromatography (LC) system using a super hot water eluent is described. The system, constructed in-house from readily available components, has been shown to operate at temperatures as high as 370 °C and pressures in excess of 10 000 psi. The capability of the system is demonstrated with the separation of a mixture of polar and non-polar benzene derivatives on polybutadiene and elemental carbon modified zirconia packings with or without temperature gradients. Six benzene derivatives can be separated in 2 min. 相似文献
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