Background and objectives: The importance of Cassia angustifulia is due to its laxative properties. A large number of sennosides have been reported in senna but sennoside A and B have been reported as the main causes of its properties. The present study includes the analysis of the effective ingredients of sennosides containing senna products in Iranian pharmaceutical ...

To resolve the biggest problem in visible-to-UV photon upconversion based on sensitized triplet-triplet annihilation-the quenching of upconverted fluorescence by sensitizers-we discovered a superior sensitizer with less UV absorption intensity that enables highly efficient, low-power (0.78 mW cm(-2)) visible-to-UV upconversion.

in order to improve uv and visible lights photocatalytic activities of the pure anatase tio2, a novel and efficient n-doped tio2 photocatalyst was prepared by sol-gel method. n-doped titania is prepared using triethylamine (with difference molar ratios) as the nitrogen source. the crystalline structure, morphology, particle size, absorbance and band-gap and chemical structure of n-doped tio2 wa...

bacteriorhodopsin (br) is the light harvesting and photoactive proton pump found in the membrane of a salt marsh bacteria. this protein has significant potential to use in optical computing and memory devices due to unique intrinsic physical properties of photo and bioelectric. all these features make br one of the most promising protein candidates in protein memories. protein memory is a kind ...

using a time-dependent-density functional theory (td-dft), configuration interaction singles (cis) and zerner’s intermediate neglect of differential overlap (zindo) methods, we have investigated the uv-visible spectra of one new intramolecular cyclization at before and after intramolecular attack. all structures were optimized at the b3lyp/6-311++g** level while uv-visible parameters were calcul...

The objective of good laboratory practice (GLP) is to obtain accurate and precise results, using a measurement system that is functioning properly and to the specifications required by global regulatory bodies such as the United States Pharmacopeia (USP) and European Pharmacopoeia (EP). The Agilent Cary 8454 UV‐Visible spectroscopy system includes a UV‐Visible instrument based on leading LC pho...

Comparing measured and estimated count rates of a few selected sample stars, we connrm the validity and provide the in-ight calibration of the ROSAT HRI UV/Visible eeective area model in Zombeck et al. 1997, ApJ, 487, L69. The count rate estimates for Betelgeuse derived with this model are in agreement with the measured HRI upper limit. This result is also connrmed in an erratum by Berghh ofer ...

The sun is the most important source of visible and ultraviolet (UV) radiation. Even though the distance from the sun to the Earth is large – about 150×10 km – the fluence rate of solar radiation on Earth, the solar constant, is about 1 360 W/m 2 . Approximately 40% of this radiation is reflected back into space. The remaining 60% is the driving force of all life on Earth. A number of pigments ...