Synthesis and Spectrum of Novel Pyrazoline Fluorescent Compounds

Pyrazoline derivatives have been used widely in dyeing industry as fluorescent whitening agents due to their excellent capability. According to Schellhammer theory of the relation between chemical structure and fluorescent quality, six new fluorescent compounds were designed and synthesized which contained the benzothiazole group in the I-pyrazoline, the indole group in the 3-pyrazoline and the derivatives of phenyl in the 5-pyrazoline. The structure of target compounds was confirmed by IR, H-1 NMR, MS and elementary analysis. The fluorescence spectra showed that these compounds had good fluorescence. They could absorb ultraviolet light at near 353 nm. The fluorescence maximum emission wavelengths were about 430-443 nm. It was a kind of promising fluorescence compounds. The largest fluorescence emission wavelength and the fluorescence intensity were related to the substituted group of the compounds. When the 6-Br group was introduced into benzothiazole, the fluorescence emission wavelength exhibited a blue shift, and the fluorescence intensity increased.

Infrared spectrum of 2-octadecyl-7,7,8,8-tetracyanoquinodimethane

Infrared spectrum of 2-octadecyl-7,7,8,8-tetracyanoquinodimethane was dealt with 2nd-derivative and deconvolution methods. It was first discovered that the band near 2849 cm(-1) assigned to the CH2 Symmetric stretching mode splited into two bands and this splitting might result from the coexistence of two kinds of conformations of CH2 in the hydrocarbon chain.

Measurement of the single-color three-photon resonant ionization spectrum of atomic uranium under the "equivalent wavelength effect laser" interaction

Using Nd: YAG laser (532 nm) pumped mixed-dye laser. we obtained the output of this dye enhanced at the wavelength interval equivalent to that given by the copper vapor laser pumped dye laser. This measure favored is with the measurement of single-color three-photon resonant ionization spectrum of atomic uranium in the range of 562-586 nm,which is otherwise not efficiently covered by Nd: YAG laser pumped dye laser with any single dye. Thus 140 U I energy levels were obtained and the peaks of interest 575.814 nm and 575.836 rim were well resolved and their relative intensity determined.

X-ray photoelectron spectroscopy and mass spectrum of organic tin compounds

The relationship between the chemical displacement of the binding energy and the different chemical environment for 12 organic tin compounds was studied by means of X-ray photoelectron spectronscopy. The different substituents in the compounds have influence on the tin outer electron and Sn-O bond, which was discussed by Xray photoelectron spectroscopy and mass spectrum.

ASSIGNMENT OF C-13 NMR-SPECTRA OF POLYMER WITH SEMIEMPIRICAL METHOD - SURVEY OF SPECTRUM OF SECONDARY CARBON OF 1,2-PBD

In chain molecules of 1, 2-PBD, there are two kinds of gauche arrangements, which is the cause of making the spectrum of the secondary carbon in main chain of the polymer split. In such a complex system, the gauche arrangements of the secondary carbon and the tertiary carbon occupy an important position. Hence, the contribution of the tertiary carbon to the chemical shifts of the secondary carbon has a decisive effect on the sequence structure distribution. In comparison the contribution of vinyl groups is ...

A METHOD OF FITTING TO MOSSBAUER SPECTRUM OF EU-151 AND ITS APPLICATION TO EUROPIUM COMPOUNDS

A method of fitting to Mossbauer spectrum of 151Eu has been proposed. The intensities and the positions of all the possible transitions between the sublevels of the ground state and those of the excited state of nucleus with spin I> 3/2 can be considered at one time in fitting to experimental Mossbauer spectra by this method. The method has been used to fit to the experimental Mossbauer spectra of europium orthophosphate crystal and of europium pentaphosphate crystal, and to derive Mossbauer parameters from...

Three dimensional fluorescence excitation-emission on matrix spectrum of dissolved organic substance in marine microalgaes growth process

The three-dimensional fluorescence spectrum was used to detect the changes in dissolved organic substances from the cultured Skeletonema costatum, Alexandrium tamarense, Alexandrium mimutum, Scrippsiella trochodea, Prorocentrum donghaiense and Prorocentrum micans. The result indicates that all of the microalgaes can produce FDOM in the growth courses. Diatom such as Skeletonema costatum can produce humic-like FDOM. However dinoflagellate can produce protein-like FDOM at exponential growth phase. When the algae grows into decadency phase, the intensity of humic-like and protein-like fluorescence augments rapidly, which may be due to a mass of FDOM realeased by the old or dead cell fragmentation and the degradation of bacteria by using non-FDOM. The fluorescent intensity of Alexandrium tamarense, Alexandrium mimutum, Prorocentrum donghaiense and Prorocentrum micans can reduce at anaphase of decadency phase because of the degradation of bacteria and light. The same genus of algae can produce similar FDOM, for example: Alexandrium tamarense, and Alexandrium mimutum, Prorocentrum donghaiense and Prorocentrum micans, but the positions of the fluorescence peaks are different.

Algebraic approach to stretching vibrational spectrum of H2S

The stretching vibrational spectra of H2S have been calculated by using the algebraic model, and the local mode characteristics have been analyzed. Within the vibrational quanta v=5, the standard deviation is 1.71 cm(-1), which is better than that from the local model HCAO model calculation.

Franck-Condon simulation of the photoelectron spectrum of SO2- including Duschinsky effects

A theoretical method to calculate multidimensional Franck-Condon factors including Duschinsky effects is described and used to simulate the photoelectron spectrum of the anion SO. Geometry optimizations and harmonic vibrational frequency calculations have been performed on the XA(1) state of SO2 and (XB1)-B-2 state of SO2. Franck-Condon analyses and spectral simulation were carried out on the first photoelectron band of SO2. The theoretical spectra obtained by employing CCSD(T)/6-31 I+G(2d,p) values are in excellent agreement with the experiment. In addition, the equilibrium geometric parameters, r(c)(OS) = 0.1508 +/- 0.0005 nm and theta(e)(O-S-0) = 113.5 +/- 0.5 degrees, of the (XB1)-B-2 state of SO2, are derived by employing an iterative Franck-Condon analysis procedure in the spectral simulation. (c) 2005 Elsevier B.V. All rights reserved.

A Spectrum of TCP-Friendly Window-Based Congestion Control Algorithms

The increased diversity of Internet application requirements has spurred recent interests in transport protocols with flexible transmission controls. In window-based congestion control schemes, increase rules determine how to probe available bandwidth, whereas decrease rules determine how to back off when losses due to congestion are detected. The parameterization of these control rules is done so as to ensure that the resulting protocol is TCP-friendly in terms of the relationship between throughput and loss rate. In this paper, we define a new spectrum of window-based congestion control algorithms that are TCP-friendly as well as TCP-compatible under RED. Contrary to previous memory-less controls, our algorithms utilize history information in their control rules. Our proposed algorithms have two salient features: (1) They enable a wider region of TCP-friendliness, and thus more flexibility in trading off among smoothness, aggressiveness, and responsiveness; and (2) they ensure a faster convergence to fairness under a wide range of system conditions. We demonstrate analytically and through extensive ns simulations the steady-state and transient behaviors of several instances of this new spectrum of algorithms. In particular, SIMD is one instance in which the congestion window is increased super-linearly with time since the detection of the last loss. Compared to recently proposed TCP-friendly AIMD and binomial algorithms, we demonstrate the superiority of SIMD in: (1) adapting to sudden increases in available bandwidth, while maintaining competitive smoothness and responsiveness; and (2) rapidly converging to fairness and efficiency.

A Spectrum of TCP-friendly Window-Based Congestion Control Algorithms

The increasing diversity of Internet application requirements has spurred recent interest in transport protocols with flexible transmission controls. In window-based congestion control schemes, increase rules determine how to probe available bandwidth, whereas decrease rules determine how to back off when losses due to congestion are detected. The control rules are parameterized so as to ensure that the resulting protocol is TCP-friendly in terms of the relationship between throughput and loss rate. This paper presents a comprehensive study of a new spectrum of window-based congestion controls, which are TCP-friendly as well as TCP-compatible under RED. Our controls utilize history information in their control rules. By doing so, they improve the transient behavior, compared to recently proposed slowly-responsive congestion controls such as general AIMD and binomial controls. Our controls can achieve better tradeoffs among smoothness, aggressiveness, and responsiveness, and they can achieve faster convergence. We demonstrate analytically and through extensive ns simulations the steady-state and transient behavior of several instances of this new spectrum.