Chemiluminescent spectra

PMs are orange-colored, with an absorption maximum at 488 nm (Fig. 9.6). The absorption characteristics and chemiluminescence activities of those compounds are shown in Table 9.4. All PMs are brightly fluorescent in yellow in organic solvents and also in aqueous solutions containing a surfactant (emission maxima 520-530 nm). The chemiluminescence spectra of PMs are significantly affected by the... 

The bioluminescence spectrum of P. stipticus and the fluorescence and chemiluminescence spectra of PM are shown in Fig. 9.7. The fluorescence emission maximum of PM-2 (525 nm) is very close to the bioluminescence emission maximum (530 nm), but the chemiluminescence emission maximum in the presence of a cationic surfactant CTAB (480 nm) differs significantly. However, upon replacing the CTAB with the zwitter-ionic surfactant SB3-12 (3-dodecyldimethylammonio-propanesulfonate), the chemiluminescence spectrum splits into two peaks, 493 nm and 530 nm, of which the latter peak coincides with the emission maximum of the bioluminescence. When PM-1 is heated at 90°C for 3 hr in water containing 10% methanol, about 50% of PM-1 is converted to a new compound that can be isolated by HPLC the chemiluminescence spectrum of this compound in the presence of SB3-12 (curve 5, Fig. 9.7) is practically identical with the bioluminescence spectrum. 

Fig. 9.9 Luminescence spectrum of a young fruiting body of Fanellus stipticus (1) the chemiluminescence spectra of PM-1 in the presence of CTAB (2) hexadecanoyl-choline iodide (3) and tetradecanoylcholine chloride (4). Chemiluminescence was elicited with Fe2+ and H2O2 in 50mM Tris buffer, pH 8.0, containing 0.18mM EDTA.

Figure 2 Comparison of NO + 03 and NO + O chemiluminescence spectra with blue and red optical filter transmissions and the response of a blue-sensitive photomultiplier tube. Note the blue shift of the NO reaction with O compared to that with 03 and that the addition of a blue filter effectively removes emission from NO + 03, while the red filter effectively removes emission from NO + O.

A background emission underlies all chemiluminescence spectra obtained in reactions of O atoms. This emission results from the recombination of O atoms,... 

Figure 5 Comparison of SO + O and SO + 03 chemiluminescence spectra. Note the blue shift of the SO + O spectrum as compared to that of SO + 03. (Adapted from Refs. 25, 152).

Fig. 7. Comparison of chemiluminescence spectra with the fluorescence spectra of rubrene. Solvent dimethylformamide. (From ref. 9.)...

Time-resolved chemiluminescence spectra are obtained as follows. For a given optical path difference, the entire temporal profile of the pulse of product IR chemiluminescence is recorded at the detector, amplified, digitized (up to 10 ns resolution) and stored directly on hard disc for a preset number of photolysis laser shots, the number depending on the SNR of the system. The C02 laser energy for each shot is recorded by a pyroelectric... 

Figure 8. Three-dimensional representation of the time evolution of the IR chemiluminescence spectra following the IRMPD of CH2F2 in the presence of O atoms. Conditions were 28.5mTorr CH2F2, 12.0mTorr O atoms, 5.09 Torr total pressure, unapodized FWHM resolution of 6.04 cm 1, Nyquist wavenumber 7901.4 cm"1 with the signal obtained for 1 shot per sampling point. The data were digitized at 30 /is resolution, but are shown here with 150/is between spectra and have been corrected for the instrument function. Emission from HF near 4000 cm-1 and CO near 2000 cm-1 is clearly seen. Reproduced with permission from Ref. 40.

Fig. 5.9 (A) Chemiluminescence intensity measured at >420 nm after the end of excitation of Ti02 in aqueous solution containing 0.1 mM luminol and 10 mM NaOH. Addition of 0.2 mM H202 causes a shift of the slow-decay part. (B) Chemiluminescence spectra measured for the two-decay part in the decay profile, showing that both parts originate from luminol.

Obtaining product energy distributions from the intensities of chemiluminescence spectra is relatively straightforward, requiring a knowledge of the appropriate transition probabilities and the spectral efficiency of the detector. One complication that can arise in the analysis of chemiluminescence data is the possibility of cascading an emitting state... 

Most reactions that have been studied in molecular-beam experiments are insufficiently exothermic to cause true electronic excitation of either of the products. Ottinger and Zare [39] have shown that where such excitation does occur, it is not difficult to observe chemiluminescent spectra from the reaction zone using a scanning monochromator and photomultiplier. Because the radiative lifetime of the excited state is short and the total pressure is very low, the vibration-rotation distribution observed within the excited state will be unrelaxed, but it is less easy to determine the proportion of reactive encounters leading to electronically excited products. 

Chemiluminescence spectra of AlF(a n) produced in crossed-beam reaction of A1 with Fj t Tandem axis LMR/resonance fluorescence/resonance absorption fast-flow system used to study N + 0H,H02 and 0 + 0H,H02... 

Figure 14. Chemiluminescence spectra of CaBr following different excitations of the Ca- HBr complex, as indicated by arrows connecting the excitation region on the action spectrum (displayed vertically at the left of the figure) to the corresponding chemiluminescence spectrum (shown horizontally). From top to bottom Pb, Pa the ratios, from simulations, are (A/B)p = 2 and (A/B)p = 1.1, respectively. Next come Db and Da whose ratios are 11 and 5, respectively. Adapted from Ref. [245].

The chemiluminescence reactions of the phthalhydrazides (la-g) were carried out in the aerobic DMSO solution in the presence of BuOK. The chemiluminescence intensities relative to the luminol chemiluminescence are also described in Table 1. As expected from their strong fluorescence, If and Ig produced much stronger chemiluminescence than the others. Since their chemiluminescence spectra agreed well with the fluorescence spectra of the corresponding potassium phthalates, the emitters are the phthalate ions (2f and 2g) similar to the luminol chemiluminescence. 

The crowned isoluminol 1 has been prepared by the route shown in Scheme 1 and confirmed by NMR, IR, UV-VIS spectra as well as HRMS. The chemiluminescence spectra were recorded on a multi-channel photodiode array detector (Hamamatsu Photonics). 

Figure 2. Chemiluminescence spectra of the crowned isoluminol 1 (0.72 mM) in MeCN in the presence of H2O2 (90 mM) and TBAOH (6.7 mM) detected upon addition of alkali-metal iodides (8 mM).

All chemicals except synthetic materials were commercially available and used as it was. Chemiluminescence and fluorescence spectra were recorded on a JASCO FP-777 fluorescence spectrophotometer. The chemiluminescence spectra induced by superoxide was measured in a mixture of 20-piL methanolic solution (1 mM) of an imidazopyrazinone derivative and 1 mL of 0.2 M phosphate buffer with various pH containing 100 mM KCl,... 

Figure 1. (A) Chemiluminescence spectra of la induced by sup oxide in phosphate buffe at 25 °C with various probe concentrations, and (B) plots of the ratio of the superoxide-triggered luminescence intensity, for la in Mops buffer at 25 °C.

Chemiluminescence intensities were obtained as follows xanthine oxidase (0.37 units/mL, 40 pL) was added to the mixture consisting of 20 mM Mops/0.2 M KCl (pH 7.2, 0.5 mL), 0.3 mM hypoxanthine (0.5 mL), and 25 mM probe in water at 25 °C, then the reaction mixture was placed in an Aloka Luminescence Reader BLR-301 and chemiluminescent intensity time curves were obtained at 25 °C. Immediately after xanthine oxidase was added, the chemiluminescence with maximum intensity was observed. The intensity of background chemiluminescence was measured before the addition of xanthine oxidase. Chemiluminescence spectra were obtained as follows the luminescence solution was placed in a JASCO FP-750DS spectrofluorometer and spectra were obtained without light-irradiation. 

In order to find amphiphilic, less hydrophilic derivatives we used various kinds of organic acids as the source of counter anions of LUC derivatives. Strong acids such as 2-bromoethanesulfonic acid and tetracyanohydroquinone readily formed LUC derivatives, BES and TCHQ in route a. On the other hand, LUC derivatives from rather weak acids such as malonic acid monoethyl ester and benzoic acid could not be purified by conventional methods. Therefore we developed a new synthetic method, route b to afford pure LUC derivatives, MA, MAE, BA, SAL, BrBA, CBA, MMT, FBA, 3,5-DABA. All of them showed characteristic absorption, fluorescence and chemiluminescence spectra of bicridinium di-cation as LUC itself. These features indicate that these derivatives are as useful chemiluminescent probes as LUC. The specific reactivity of MMT toward superoxide among ROS (02, H2O2, HCIO, OH, 02) was examined by using chemically produced ROS. It is confirmed that MMT has the specific reactivity as well as LUC. 

The chemiluminescence (intensity of light was rather weak and decreased slowly) and fluorescence spectra were recorded on a Shimadzu RF-510 spectrofluorometer. The chemiluminescence spectra (intensity of light was very strong but decreased instantly) were recorded on an Otsuka Electronics IMCPD-IIO spectro multi channel photodetector. The absorption spectra were obtained with a Shimadzu UV-240 spectrophotometer. 

Chemiluminescence spectra of emissions I and m with very short duration were successfully recorded on the photodetector. Fig. 5 shows variation of the spectra of emission I with time, whose maxima appeared at around 520 nm. Since emission H was too weak to record on the photodetector, the emission spectrum... 

Fig. 5. Variation of chemiluminescence spectra of emission 1 of adsorbed 1b on activated alumina in a benzene slurry with time. Curve 1 immediately after addition of activated alumina to the benzene solution of lb. Curve 2 and following curves measured after every 0.8 sec.

First, we examined BID of 1. When 1 was treated with tetrabutylammonium fluoride (TBAF) in A-methylpyrrolidone (NMP) at 45 °C, chemiluminescence occurred effectively with An,axBI = 498 nm, (P610 = 0.29, and rate constant BID = ln2/ti/2BID = 2.5 x 10 4 s 1 (vide infra). The BID of 1 also proceeded to give bright light in acetonitrile,3 DMF and DMSO. The chemiluminescence spectra for BID of 1 are... 

On treatment with potassium t-butoxide instead of sodium t-butoxide in THF, dioxetane 2 decomposed more rapidly (kCTICL - 0.11 s 1) to emit a flash of light with AmaxCTICL = 539 nm. The chemiluminescence spectrum is illustrated in Fig. 3 together with chemiluminescence spectra for TBAF system and for the other alkaline metal t-butoxide (vide infra). 0 decreased to 4.5 x 10 though it was yet effective 10 times more than that in the TBAF system. Finally, we carried out the decomposition of 2 with lithium t-butoxide in THF. Lithium ion in general coordinates strongly to oxidoaryl anion in an organic solvent because of the smallest ion radius, thus, we did... 

FIGURE 3.1 Chemiluminescence spectra under nitrogen of HDPE, LLDPE, and mPE polymers at 170°C. 

FIGURE 3.11 Chemiluminescence spectra under oxygen of UV-degraded PECT samples (free additive) at different aging times. 

Tribophosphorescence in aniline hydrochloride and coumarin 376 and recombination luminescence in benzene and L-tryptophan 376 have also been discussed, and some chemiluminescence spectra of CN, SrO, and FeO presented.377... 

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