The effects of N-methylphenazonium methosulfate (PMS) have been compared with three other phenazine dyes and N, N, N’, N’-tetramethyl-&phenylenediamine (TMPD). All accelerate the recovery of the initial absorbance changes in Rhodospirillum rubrum extracts induced by a lO+ec flash, although only N-ethylphenazonium ethosulfate and TMPD stimulate photophosphorylation to the same extent as PMS. N-E...

An improved and greener protocol for the synthesis of benzimidazole derivatives, starting from o-phenylenediamine, with different aldehydes is reported. Double-condensation products were selectively obtained when Er(OTf)3 was used as the catalyst in the presence of electron-rich aldehydes. Conversely, the formation of mono-condensation products was the preferred path in absence of this catalyst...

In this article we demonstrate the performance of a direct conversion amorphous selenium (a-Se) X-ray detector using biphenyldisnhydride/1,4 phenylenediamine (BPDA/PPD) polyimide (PI) as a hole-blocking layer. The use of a PI layer with a-Se allows detector operation at high electric fields (≥10 V/μm) while maintaining low dark current, without deterioration of transient performance. The hole m...

Hypersensitivity to para-phenylenediamine (PPD) and related compounds induced by temporary black henna tattoos has become a serious health problem worldwide. Different patterns of sensitization with various clinical aspects are described in literature due to PPD associated to henna tattoo and these manifestations are likely correlated with the immunological and dermatological pathomechanisms in...

The Cosmetic Ingredient Review Expert Panel (CIR Panel) reviewed the safety of hydroxypropyl bis(N-Hydroxyethyl-p-Phenylenediamine) HCl, which functions as an oxidative hair dye ingredient. The Panel considered relevant animal and human data provided in this safety assessment and concluded that hydroxypropyl bis(N-hydroxyethyl-p-phenylenediamine) HCl is safe for use in oxidative hair dye formul...

A 20-year-old female dental assistant experienced an acute dermatitis at the site of a temporary ‘henna’ tattoo that had been applied 3 days earlier. It transpired that ‘henna’ tattoos had been applied on previous occasions. After the above episode, she subsequently developed eczematous reactions on the face, neck and upper back within a few days of dyeing her hair with dark brown or black colo...

A method for determining iron in seawater had been developed by coupling reverse flow injection analysis (rFIA) and catalytic spectrophotometric detection with N,N-dimethyl-p-phenylenediamine dihydrochloride (DPD). With a seawater sample or a standard solution as the carrier, the mixture of DPD and buffer was injected into the carrier stream quantitatively and discretely. After mixing with H(2)...

a library of benzimidazole derivatives have been prepared through the reaction of o-phenylenediamine and aldehydes in the presence of catalytic amount of silica supported sodium hydrogen sulphate (NaHSO4-SiO2) under refluxing in ethanol solvent to obtained excellent yields. This method is simple, convenient, environmental friendly, reusable, efficient and practical.