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91.
The failure of selection rules on Ka, v, and vibronic symmetry in the visible band systems of NO2 are interpreted as resulting from the coupling of the excited electronic state with vibrational levels of the ground electronic state which are above the threshold for ergodic motion and therefore retain no quantization of those observables. This failure is shown to lead directly to the anomalous continuum fluorescence of NO2, and is intimately related to the anomalous lengthening of the radiative lifetime of the excited state (the Douglas effect). It is predicted that most molecules which exhibit anomalous lifetime lengthening will also exhibit anomalous selection rules and, consequently, anomalous continuum emission.  相似文献   
92.
Using the ACCMOR spectrometer equipped with a vertex telescope of high resolution silicon microstrip detectors 74 decays \(D^ + \to \bar K^{*0} (892)e^ + v_e \) (andcc.) withx F <0.4 have been observed in 200 GeV π? Be interactions. The cross-section forD ± production, itsx F -dependence in the central region and theD ± lifetime have been measured.  相似文献   
93.
Experimental results on inclusive ? production are compared with the Lund model for lowp T hadronic interactions. The data is based on a sample of 600,000 ? mesons in the kinematic rangep T <1.0 (GeV/c)2 and 0.0<x F<0.4, produced in π±,K ±,p and \(\bar p\) Be interactions at 100 GeV/c and 120 GeV/c incident momentum. The Lund model reproduces the shapes of the longitudinal differential cross sections reasonably well, but the relative cross sections for incident, π,K andp show a discrepancy with the data.  相似文献   
94.
ICP-AES法测定色漆可溶性金属含量   总被引:1,自引:0,他引:1  
用ICP-AES法测定了色漆中的“可溶性”金属铬、镉、铅元素,考察了不同酸度对分析结果的影响,优化了测试条件。进行了回收率和精密度试验。并用原子吸收光谱国标方法进行对照,结果一致。  相似文献   
95.
A medical device using riboflavin (RB) and light is being developed for the reduction of pathogens in platelet concentrates (MIRASOL pathogen reduction technology [PRT]). A high-performance liquid chromatography (HPLC) method for the quantification of RB and its main photoproduct, lumichrome (LC) in blood components has been developed and validated. In addition, the same method has been used to identify and quantify the presence of additional photoproducts-catabolites of RB. Levels of these agents before and after treatment as well as endogenous levels present in normal donor blood are reported using this analytical technique. The method allows for quantitative and qualitative analysis of RB and LC in blood components using HPLC-fluorescence detection, a Zorbax SB-CN (stable bond cyano) column and a methanol-water mobile phase. Quantitation and qualitative analysis of additional photoproducts of RB was also performed, but the method has not been validated for these other components. The method described has passed an 8 day validation and has been found to be adequate for its intended use. The range of the method for RB is 0.016-1.500 microM and for LC is 0.060-1.500 microM. The method detection limit for RB is 0.0006 microM and for LC is 0.012 microM. The acceptance criteria for repeatability were met; the relative standard deviation for RB was 0.64% and for LC was 0.76%. The acceptance criteria for bias were met with a 97% average recovery for RB and a 102% recovery for LC. Samples were centrifuged and diluted 1:50 with 0.9% saline before analysis. No protein precipitation or extraction was required. A mass balance of approximately 93.4-94.4% was achieved after exposure of products to UV light in the intended pathogen reduction treatment method. The method permitted the identification of photoproducts in blood that were both naturally occurring and produced after photolysis of blood samples treated with the PRT process. The identity of these photoproducts has been established using HPLC Tandem Mass Spectrometry (MS/MS) and UV spectroscopic methods and has been correlated with known metabolites and catabolites of RB. HPLC with fluorescence detection using a reverse phase cyano-column allows for accurate separation, identification and quantification of both RB and LC in blood products without the need for solvent extraction or protein precipitation. Additional photoproducts could also be identified and quantified using this method. The presence of these agents in normal, untreated blood suggests that their presence in blood is ubiquitous.  相似文献   
96.
The title compounds were prepared from 1-lithio-undecafluorobicylco(2,2,1)-heptane, and from 1H,4-lithio-decafluorobicyclo(2,2,1)heptane and 1H-decafluorobicyclo(2,2,1)hept-4-yl magnesium iodide with mercuric chloride. With sulphur and caesium fluoride in dimethyl formamide, both mercurials gave the corresponding thioxides and these on hydrolysis gave the known bridgehead thiols. With sulphur alone, the undecafluoro mercurial gave mainly the disulphide and a range of polysulphides, under conditions which left the 4H-decafluoro mercurial unchanged. Conventional d.c. polarography of the mercurials indicated an inconsistency in the use of this method for determining the acidities of highly fluorinated hydrocarbons.  相似文献   
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