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61.
UV/Vis光谱法研究红子色素的稳定性   总被引:1,自引:0,他引:1  
本文报导了从红子提取,分离天然色素及酸碱和温度等对该色素稳定性的影响。  相似文献   
62.
Zusammenfassung Es wird ein Verfahren zur Bestimmung von g/g- bis mg/g-Gehalten Arsen in Blei und Bleilegierungen beschrieben. Das Arsen wird dazu mit NaBH4 als AsH3 aus der Probenlösung ausgetrieben und atomabsorptions-spektrometrisch in einer geheizten Quarzküvette bestimmt. Durch geeignete Arbeitsbedingungen werden Störungen durch die Matrix ausgeschaltet. Für den gesamten Arbeitsbereich beträgt die relative Standardabweichung etwa 3% (N=12); die Nachweisgrenze (3 -Grenze) wurde zu 0,1 g/g As ermittelt.
Determination of arsenic in lead and lead alloys
Summary A method is described for the determination of g/g to mg/g concentrations of As in lead and lead alloys. For that purpose arsenic is blown out from the sample solutions as AsH3 by use of NaBH4 and determined by AAS in a heated quartz cuvette. Using suitable conditions disturbances caused by the matrix are eliminated. The relative standard deviation over the whole working range is about 3% (N=12); the detection limit (3 ) was found to be 0.1 g/g As.
  相似文献   
63.
In this work, we describe and evaluate the use of the Fourier transform infra red (FTIR) spectroscopy in DRIFT mode (diffuse reflectance infra red Fourier transform) in an environmental device to follow the functional evolution of cellulose during thermal treatments. The potentialities (and difficulties) of the technic are given. This revised version was published online in July 2006 with corrections to the Cover Date.  相似文献   
64.
This work concerns the studies of energy transfers between Sm3+ and Eu3+ ions in some phosphates as new luminescent materials emitting in the orange-red color. The choose of ions is based on the possibility of quantum cutting process and the matrices are selected according to the 5d bands position of Sm3+ ion. The Sm3+ and Eu3+ doped YPO4, LaP5O14 and LaP3O9 are synthesized and spectroscopic studies in ultraviolet and vacuum ultraviolet ranges have been achieved.  相似文献   
65.
A spring model is used to simulate the skeleton structure of the red blood cell (RBC) membrane and to study the red blood cell (RBC) rheology in Poiseuille flow with an immersed boundary method. The lateral migration properties of many cells in Poiseuille flow have been investigated. The authors also combine the above methodology with a distributed Lagrange multiplier/fictitious domain method to simulate the interaction of cells and neutrally buoyant particles in a microchannel for studying the margination of particles.  相似文献   
66.
67.
We have realized the microscopic simulation of olefin polymerization, that is, the simulation of the catalytic polymerization (CP) reaction system composed of (pyridylamido)hafnium(IV) complex as the catalyst. For this purpose, we adopted Red Moon (RM) method, a novel molecular simulation method to simulate the complex reaction system. First, according to the previous research, with the help of the QM calculation, we proposed a model system and elementary processes and explained the theoretical treatment of the simulation by the RM method (the RM simulation). In addition, we also proposed a macroscopic simulation based on chemical kinetics simulation. Then, we performed two simulations and compared them in terms of the effective time evolution of the three macroscopic physical quantities, the number-average molecular weight Mn , the mass-average molecular weight Mw , and the molar-mass dispersity ĐM . The comparison showed that the two simulations are in quantitative or partially qualitative agreement with each other. Therefore, it is concluded that the RM simulation could not only simulate the CP reaction process microscopically, but also it is connected essentially to reproduce the time evolution of the macroscopic physical quantities on the basis of its microscopic simulation data. © 2018 Wiley Periodicals, Inc.  相似文献   
68.
Secondary batteries such as Li‐ion battery are expected to be utilized as not only ubiquitous electric power sources such as mobile phones but also large‐scale electricity storage devices. Therefore, it is urgent to develop the higher performance secondary batteries. Their lifetime and stability are found to be strongly dependent on the nature of passivation film called solid electrolyte interphase (SEI) film formed on the anode surface in the initial charge‐discharge cycle. However, since it is difficult to directly observe the film formation processes in experiment, its microscopic mechanism is still not found. On the other hand, although the theoretical methods are useful complement to the experiment, some new methodologies are necessary to understand the long‐term processes of SEI film, which is produced as a result of that a lot of chemical reactions proceed simultaneously. Under the circumstances, we have developed Red Moon method that can simulate such complex chemical reaction systems, and were able to analyze for the first time the SEI film formation processes on the anode surface at the atomistic level. Then, we clarified theoretically the microscopic mechanism of the additive effect which is essential to improve the Na‐ion battery performance so as to enhance the SEI film formation. This new microscopic insight must provide an important guiding principle for use in designing the most suitable electrolytes for developing high‐performance secondary batteries.  相似文献   
69.
Organic light-emitting diodes (OLEDs) based on the blend of two blue luminescent materials N,N′-bis(1-naphthyl)-N,N′-diphenyl-1,1′-diphenyl-4,4′-diamine (NPB) and 2-(4-biphenylyl)-5(4-tert-butyl-phenyl)-1,3,4-oxadiazole (PBD) were fabricated. The electroluminescence (EL) spectra of this device showed a new emission that is different from their intrinsic exciton emission. Compared with the photoluminescence (PL) spectra of single layer NPB and PBD, respectively, there was an apparent red shift in that of their blend. Thus the exciplex formation in the blend can be concluded due to the similar emission in both PL and EL spectra. The exciplex formation process and the effect of applied voltage were analyzed by Gaussian fitting.  相似文献   
70.
The Y0.85Bi0.1Eu0.05V1−yMyO4 (M=Nb, P) as new near-ultraviolet excited phosphors were synthesized and their luminescence properties under 365 nm excitation were investigated in detail. It indicated that by doping small amount of P5+ into V5+ sites, the excitation intensity of charge transfer (CT) band of Bi–O (330–400 nm) was greatly improved. By substituting Nb5+ for V5+, both the CT bands of Bi–O and Eu–O (240–320 nm) were significantly enhanced. As a result, the emission intensity of Y0.85Bi0.1Eu0.05V1−yMyO4 (M=Nb, P) could be improved about 90% by doping 5 mol% P5+ and 110% by doping 5 mol% Nb5+. Comparing with the commercial Y2O2S:Eu3+ phosphors, the Y0.85Bi0.1Eu0.05V0.95M0.05O4 (M=Nb, P) phosphors exhibited excellent color purity and much higher brightness. The results showed that these Y0.85Bi0.1Eu0.05V1−yMyO4 (M=Nb, P) phosphors could be considered as promising red phosphors for application in LED.  相似文献   
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