Naphthyl ethylene

Nitric Add — Sodium Dithionite-Sodium Nitrite—N-(l-Naphthyl)-ethylene-... 

Spencer and Brewer [144] have reviewed methods for the determination of nitrite in seawater. Workers at WRc, UK [ 145] have described an automated procedure for the determination of oxidised nitrogen and nitrite in estuarine waters. The procedure determines nitrite by reaction with N-1 naphthyl-ethylene diamine hydrochloride under acidic conditions to form an azo dye which is measured spectrophotometrically. The reliability and precision of the procedure were tested and found to be satisfactory for routine analyses, provided that standards are prepared using water of an appropriate salinity. Samples taken at the mouth of an estuary require standards prepared in synthetic seawater, while samples taken at the tidal limit of the estuary require standards prepared using deionised water. At sampling points between these two extremes there will be an error of up to 10% unless the salinity of the standards is adjusted accordingly. In a modification of the method, nitrate is reduced to nitrite in a micro cadmium/copper reduction column and total nitrite estimated. The nitrate content is then obtained by difference. 

Figure 2.4. Flow diagram for the colorimetric determination of nitrite and nitrate. The internal diameter of the Tygon tubing was 0.64 mm for the 0.23 ml/min flow rates and 1.30 mm for the 1.00 ml/min flow rates all other tubing was 0.7 mm id. The reagents were (A) carrier stream, (B) sulfanilamide solution, and (C) N(1-naphthyl) ethylene diamine solution. S denotes the point of injection and W waste. From [168]...

Reduction of nitrate is achieved by the use of a mixing coil containing copperised cadmium wire. Spectrophotometric evaluation of the nitrite produced is achieved by the use of sulfanilamide N( 1 naphthyl) ethylene diamine hydrochloride system. 

V-(1-Naphthyl)ethylene diamine dihydrochloride, C 2Hi4N2-2HCI irritant Phosphoric acid, 85%, H3PO4 corrosive... 

In this context it is important to keep in mind, however, that di(2-naphthyl)ethylene (2 + 2) and 3-styrylphenanthrene (3 +1) form pentahelicene on irradiation, but in the presence of iodine it cyclizes into benzo[g,h,i]-perylene 17). The second cyclization... 

Polar solvents also may affect the geometrical isomerization of ethylenes by affecting the efficiency of intersystem crossing [96,97]. Thus, even in the absence of polar substituents, solvent polarity can be of importance in the photochemical isomerization of aryl-substituted ethylenes. For example, cis-l-(9-anthryl)-2-(l-naphthyl)ethylene 74 in cyclohexane isomerizes to the trans-isomer 75 with a quantum yield of 0.05, while the quantum yield in acetonitrile solution is 0.31. Any trans->cis isomerization 75—74 in cyclohexane has not been observed, but the reaction does proceed with a preparatively useful quantum yield of 0.05 in acetonitrile [98],... 

C14H13N304S 2-nitrobenzaldehyde tosylhydrazone 58809-90-8 25.00 1.3924 2 27209 C14H15IN204S N-iodoacetyl-N -(5-sulfo-1-naphthyl)ethylene 36930-63-9 25.00 1.6533 2... 

Folic acid [12] A-(1-Naphthyl)ethylene- Dulcin[13] diaminedihydrochloride ... 

Benzo-fused pyridinium systems also undergo the reaction and a new example, the photocyclisation of (153) to (154) in the presence of iodine, has been published. The quantum efficiency of photocyclisation of l,2-jbis-(a-naphthyl)ethylene to dihydropicene has been examined in micelles and the cyclisation of [5]-helicene (155) to dihydrobenzperylene (156) has been carried out at 4K (156) was characterised by its fluorescence and phosphorescence emission. The effect of different substituents on the photocyclisation of the symmetrically tetra-substituted stilbene (157) has been probed. 

Marshall reagent, 0.4 % N-( 1-naphthyl)-ethylene diammonium dichloride in methanol Sulfamethazine, standards, 0.1, 0.5, 1.0 gg/SpL in methanol... 

At room temperature the triplet lifetime of trans- and cis-stilbene is 62 ns [412, 443, 444, 448]. Values around 100ns were observed for trans-azastil-benes [428] and some phenylethylenes [299], whereas those for 2-vinyl-biphenyls [449] or l-(aryl)-2-(l-naphthyl)ethylenes [441] are longer. Shorter lifetimes were reported for styrene (26ns in benzene) [441,450]. Introduction of three methyl groups prolongs the lifetime of triplet styrene from 22 to 91 ns [448], The effects of structural features on the lifetimes of... 

ADB Br-StN CI-StN 4,4 -CDS 4,4 -CMS DHP DNE 1 -Aryl-3,3-dimethyl- 1-butene 1 -(1 -Naphthyl)-2-(4 -bromophenyl)ethylene l-(l-Naphthyl)-2-(4 -chlorophenyl)ethylene 4-Cyano-4 -dimethylaminostilbene 4-Cyano-4 -methoxystil bene 4a,4b-Dihydrophenanthrene n,n -Dinaphthylethylene, l-(n-naphthyl)-2-(n -naphthyl)ethylene... 

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