2 research outputs found
Comparative study between supported bimetallic catalysts for nitrate remediation in water
As the population grows and the demand for water rises, the development of efficient and sustainable water purification techniques is becoming increasingly important to ensure access to clean and safe water in the future. The pollution of surface and groundwater by nitrate ( NO 3 - {\text{NO}}_{3}{-} ) is a growing global concern due to the rise in nitrogen-rich waste released from agriculture and industry. The removal of nitrate ions from aqueous media using bimetallic catalysts loaded on several supports was studied. Multiwalled carbon nanotubes, activated carbon, titanium dioxide, titanium dioxide/multiwalled carbon nanotubes, and Santa Barbara Amorphous-15 were used as supports to synthesize these bimetallic catalysts. The effects of the support type, supported metal, and catalyst reduction method on the nitrate reduction activity in water were investigated. The catalysts were characterized by X-ray diffraction, fourier-transform infrared spectroscopy, Brunauer-Emmett-Teller isotherm, inductively coupled plasma spectroscopy, and field emission gun scanning transmission electron microscope. In terms of nitrate conversion, high-temperature hydrogen reduction of the catalysts was a more effective method of catalyst preparation than NaBH4 reduction. Except for the carbon nanotube-TiO2 composite, pH fixation using CO2 flow improved the efficiency of supported catalysts. The catalysts 1Pd-1Cu/TiO2 and 1Pd-Cu/SBA-15 presented the highest catalytic activity, but the latter was the most selective to nitrogen
Identification and analysis of functional elements in 1% of the human genome by the ENCODE pilot project.
We report the generation and analysis of functional data from multiple, diverse experiments performed on a targeted 1% of the human genome as part of the pilot phase of the ENCODE Project. These data have been further integrated and augmented by a number of evolutionary and computational analyses. Together, our results advance the collective knowledge about human genome function in several major areas. First, our studies provide convincing evidence that the genome is pervasively transcribed, such that the majority of its bases can be found in primary transcripts, including non-protein-coding transcripts, and those that extensively overlap one another. Second, systematic examination of transcriptional regulation has yielded new understanding about transcription start sites, including their relationship to specific regulatory sequences and features of chromatin accessibility and histone modification. Third, a more sophisticated view of chromatin structure has emerged, including its inter-relationship with DNA replication and transcriptional regulation. Finally, integration of these new sources of information, in particular with respect to mammalian evolution based on inter- and intra-species sequence comparisons, has yielded new mechanistic and evolutionary insights concerning the functional landscape of the human genome. Together, these studies are defining a path for pursuit of a more comprehensive characterization of human genome function